Microorganism

Environ Sci Technol, 2003 Apr 15, 37(8), 1575 - 80
Role of soil freezing events in interannual patterns of stream chemistry at the Hubbard Brook Experimental Forest, New Hampshire; Fitzhugh RD et al.; Soil freezing is a disturbance of the below ground environment, potentially resulting in increased losses of NO3- and surface water acidification . Here, we report the effects of soil freezing on interannual variation in stream chemistry at the Hubbard Brook Experimental Forest, New Hampshire . Data from 1970 to 1997 of soil frost depth, snow cover, precipitation, air temperature, and stream discharge and chemistry were used in a stepwise linear regression model to select the variables that best predicted deviations of annual stream concentrations from 4-year running averages . Variables quantifying soil freezing severity were selected as significant predictors of short-term fluctuations in stream K+, NO3-, Ca2+, and Mg2+ concentrations from 1970 to 1989, explaining 59 and 47% of the short-term variability in K+ and NO3-, respectively . Fine-root mortality and disturbance of root-soil-microbe interactions, with subsequent effects on decomposition and nutrient uptake, likely contributed to the mobilization of K+ and NO3- to streamwater following severe soil freezing events . The relationship between soil freezing and stream chemistry, however, weakened during the period 1990-1997 . Because soil freezing has had inconsistent effects on stream chemistry during the period 1970-1997, it is unclear whether future changes in the frequency, duration, and depth of soil freezing events as the result of changes in the snow cover regime under a warmer climate will have significant impacts on the losses of NO3- and nutrient-base cations from temperate northern ecosystems.

J Bacteriol, 2003 May, 185(10), 3147 - 54
Early colonization events in the mutualistic association between Steinernema carpocapsae nematodes and Xenorhabdus nematophila bacteria; Martens EC et al.; The bacterium Xenorhabdus nematophila is a mutualist of the entomopathogenic nematode Steinernema carpocapsae . During its life cycle, the bacterium exists both separately from the nematode and as an intestinal resident of a nonfeeding nematode form, the infective juvenile (IJ) . The progression of X . nematophila from an ex vivo existence to a specific and persistent colonization of IJs is a model to understand the mechanisms mediating the initiation and maintenance of benign host-microbe interactions . To help characterize this process, we constructed an X . nematophila strain that constitutively expresses green fluorescent protein, which allowed its presence to be monitored within IJs . Using this strain, we showed that few bacterial cells initiate colonization of an individual IJ and that these grow inside the lumen of the IJ intestine in a reproducible polyphasic pattern during colonization . In accordance with these two observations, we demonstrated that the final population of bacteria in a nematode is of predominantly monoclonal origin, suggesting that only one or two bacterial clones initiate or persist during colonization of an individual nematode . These data suggest that X . nematophila initiates IJ colonization by competing for limited colonization sites or resources within the nematode intestine . This report represents the first description of the biological interactions occurring between X . nematophila and S . carpocapsae during the early stages of the colonization process, provides insights into the physiology of X . nematophila in its host niche, and will facilitate interpretation of future data regarding the molecular events mediating this process.

Arch Microbiol, 2003 Jun, 179(6), 423 - 9 Epub 2003 May 01.
Heat-shock response and its contribution to thermotolerance of the nitrogen-fixing cyanobacterium Anabaena sp . strain L-31; Rajaram H et al.; Compared to Escherichia coli, the nitrogen-fixing soil cyanobacterium Anabaena sp . strain L-31 exhibited significantly superior abilities to survive prolonged and continuous heat stress and recover therefrom . Temperature upshift induced the synthesis of heat-shock proteins of similar molecular mass in the two microbes . However, in Anabaena sp . strain L-31 the heat-shock proteins (particularly the GroEL proteins) were synthesised throughout the stress period, were much more stable and accumulated during heat stress . In contrast, in E . coli the heat-shock proteins were transiently synthesised, quickly turned over and did not accumulate . Nitrogenase activity of Anabaena cells of sp . strain L-31 continuously exposed to heat stress for 7 days rapidly recovered from thermal injury, although growth recovery was delayed . Exposure of E . coli cells to >4.5 h of heat stress resulted in a complete loss of viability and the ability to recover . Marked differences in the synthesis, stability and accumulation of heat-shock proteins appear to distinguish these bacteria in their thermotolerance and recovery from heat stress.

EMBO J, 2003 May 1, 22(9), 2082 - 90
Rapid invasion of host cells by Toxoplasma requires secretion of the MIC2-M2AP adhesive protein complex; Huynh MH et al.; Vertebrate cells are highly susceptible to infection by obligate intracellular parasites such as Toxoplasma gondii, yet the mechanism by which these microbes breach the confines of their target cell is poorly understood . While it is thought that Toxoplasma actively invades by secreting adhesive proteins from internal organelles called micronemes, no genetic evidence is available to support this contention . Here, we report successful disruption of M2AP, a microneme protein tightly associated with an adhesive protein called MIC2 . M2AP knockout parasites were >80% impaired in host cell entry . This invasion defect was likely due to defective expression of MIC2, which partially accumulated in the parasite endoplasmic reticulum and Golgi . M2AP knockout parasites were also unable to rapidly secrete MIC2, an event that normally accompanies parasite attachment to a target cell . These findings indicate a critical role for the MIC2-M2AP protein complex in parasite invasion.

FEMS Microbiol Lett, 2003 Apr 25, 221(2), 187 - 90
Inhibitory effect of L-pyroglutamate on extremophiles: correlation with growth temperature and pH; Park CB et al.; L-Pyroglutamate (PGA) is naturally occurring from L-glutamate solution with accelerated formation rate under high temperature and low pH . Even though PGA has been identified as a neurotoxic agent on brain cells, the effect of PGA on the growth of microorganisms is rarely known . Here various kinds of microorganisms differing in their optimal growth temperature, pH, phylogeny, and isolated biotope were investigated for the effect of PGA . We found that growth of thermoacidophiles, including both archaea and bacteria, was seriously inhibited by the presence of PGA, and the extent of the inhibitory effect was closely related with growth temperature and pH . Interestingly, only microbes that grow at high temperature and low pH are inhibited by PGA, while this compound may stimulate growth rates of organisms that live at neutral pH and low temperature.

Med Phys, 2003 Apr, 30(4), 583 - 9
MOSFET dosimetry for microbeam radiation therapy at the European Synchrotron Radiation Facility; Brauer-Krisch E et al.; Preclinical experiments are carried out with approximately 20-30 microm wide, approximately 10 mm high parallel microbeams of hard, broad-"white"-spectrum x rays (approximately 50-600 keV) to investigate microbeam radiation therapy (MRT) of brain tumors in infants for whom other kinds of radiotherapy are inadequate and/or unsafe . Novel physical microdosimetry (implemented with MOSFET chips in the "edge-on" mode) and Monte Carlo computer-simulated dosimetry are described here for selected points in the peak and valley regions of a microbeam-irradiated tissue-equivalent phantom . Such microbeam irradiation causes minimal damage to normal tissues, possible because of rapid repair of their microscopic lesions . Radiation damage from an array of parallel microbeams tends to correlate with the range of peak-valley dose ratios (PVDR) . This paper summarizes comparisons of our dosimetric MOSFET measurements with Monte Carlo calculations . Peak doses at depths <22 mm are 18% less than Monte Carlo values, whereas those depths >22 mm and valley doses at all depths investigated (2 mm-62 mm) are within 2-13% of the Monte Carlo values . These results lend credence to the use of MOSFET detector systems in edge-on mode for microplanar irradiation dosimetry.

Proc Natl Acad Sci U S A, 2003 May 13, 100(10), 5664 - 9 Epub 2003 Apr 29.
The mechanism of ferrichrome transport through Arn1p and its metabolism in Saccharomyces cerevisiae; Moore RE et al.; Siderophores are low molecular weight compounds, synthesized and secreted by microorganisms, that specifically bind ferric iron with exceptionally high affinity . Microbes capture these compounds and take up the bound iron through specific, high-affinity systems . Saccharomyces cerevisiae can take up iron bound to siderophores through the transporters of the ARN family; however, the mechanism by which the siderophore-bound iron enters the cell via these transporters is not known . Here we describe how ferrichrome, a siderophore of the hydroxamate class, is taken up by Arn1p . Arn1p exhibits two surface binding sites for ferrichrome, one that is similar in affinity to the K(T) for uptake and one of a much higher affinity that is specific for the metallated form of ferrichrome . Ferrichrome may gain access to the higher-affinity site through endocytosis . Tracer studies using (14)C-labeled ferrichrome bound to either iron(III) or aluminum(III), a nonreducible ligand for ferrichrome, indicate that ferrichrome enters the cell as the intact metallosiderophore and accumulates in the cytosol . Both ferrichrome chelates were relatively stable within the cell, and metal-free ferrichrome did not accumulate, indicating a role for ferrichrome in intracellular iron storage . Iron stored as ferrichrome was readily mobilized to meet the metabolic needs of the cell.

J Exp Med, 2003 May 5, 197(9), 1107 - 17 Epub 2003 Apr 28.
Collaborative induction of inflammatory responses by dectin-1 and Toll-like receptor 2; Gantner BN et al.; Toll-like receptors (TLRs) mediate recognition of a wide range of microbial products including lipopolysaccharides, lipoproteins, flagellin, and bacterial DNA, and signaling through TLRs leads to the production of inflammatory mediators . In addition to TLRs, many other surface receptors have been proposed to participate in innate immunity and microbial recognition, and signaling through some of these receptors is likely to cooperate with TLR signaling in defining inflammatory responses . In this report we have examined how dectin-1, a lectin family receptor for beta-glucans, collaborates with TLRs in recognizing microbes . Dectin-1, which is expressed at low levels on macrophages and high levels on dendritic cells, contains an immunoreceptor tyrosine-based activation motif-like signaling motif that is tyrosine phosphorylated upon activation . The receptor is recruited to phagosomes containing zymosan particles but not to phagosomes containing immunoglobulin G-opsonized particles . Dectin-1 expression enhances TLR-mediated activation of nuclear factor kappa B by beta-glucan-containing particles, and in macrophages and dendritic cells dectin-1 and TLRs are synergistic in mediating production of cytokines such as interleukin 12 and tumor necrosis factor alpha . Additionally, dectin-1 triggers production of reactive oxygen species, an inflammatory response that is primed by TLR activation . The data demonstrate that collaborative recognition of distinct microbial components by different classes of innate immune receptors is crucial in orchestrating inflammatory responses.

J Comp Neurol, 2003 Jun 9, 460(4), 514 - 24
Nectin-dependent localization of ZO-1 at puncta adhaerentia junctions between the mossy fiber terminals and the dendrites of the pyramidal cells in the CA3 area of adult mouse hippocampus; Inagaki M et al.; Nectin and afadin constitute a novel intercellular adhesion system that organizes adherens junctions in cooperation with the cadherin-catenin system in epithelial cells . Nectin is a Ca(2+)-independent immunoglobulin-like adhesion molecule and afadin is an actin filament (F-actin)-binding protein that connects nectin to the actin cytoskeleton . At the puncta adhaerentia junctions (PAs) between the mossy fiber terminals and the dendrites of the pyramidal cells in the CA3 area of the adult mouse hippocampus, the nectin-afadin system also colocalizes with the cadherin-catenin system and has a role in the formation of synapses . ZO-1 is another F-actin-binding protein that localizes at tight junctions (TJs) and connects claudin to the actin cytoskeleton in epithelial cells . The nectin-afadin system is able to recruit ZO-1 to the nectin-based cell-cell adhesion sites in nonepithelial cells that have no TJs . In the present study, we investigated the localization of ZO-1 in the mouse hippocampus . Immunofluorescence and immunoelectron microscopy revealed that ZO-1 also localized at the PAs between the mossy fiber terminals and the dendrites of the pyramidal cells in the CA3 area of the adult mouse hippocampus, as described for afadin . ZO-1 colocalized with afadin during the development of synaptic junctions and PAs . Microbeads coated with the extracellular fragment of nectin, which interacts with cellular nectin, recruited both afadin and ZO-1 to the bead-cell contact sites in cultured rat hippocampal neurons . These results indicate that ZO-1 colocalizes with nectin and afadin at the PAs and that the nectin-afadin system is involved in the localization of ZO-1 .

Arterioscler Thromb Vasc Biol, 2003 Jul 1, 23(7), 1185 - 9 Epub 2003 Apr 24.
Endothelial progenitor cells: mobilization, differentiation, and homing; Hristov M et al.; Postnatal bone marrow contains a subtype of progenitor cells that have the capacity to migrate to the peripheral circulation and to differentiate into mature endothelial cells . Therefore, these cells have been termed endothelial progenitor cells (EPCs) . The isolation of EPCs by adherence culture or magnetic microbeads has been described . In general, EPCs are characterized by the expression of 3 markers, CD133, CD34, and the vascular endothelial growth factor receptor-2 . During differentiation, EPCs obviously lose CD133 and start to express CD31, vascular endothelial cadherin, and von Willebrand factor . EPCs seem to participate in endothelial repair and neovascularization of ischemic organs . Clinical studies using EPCs for neovascularization have just been started; however, the mechanisms stimulating or inhibiting the differentiation of EPC in vivo and the signals causing their migration and homing to sites of injured endothelium or extravascular tissue are largely unknown at present . Thus, future studies will help to explore areas of potential basic research and clinical application of EPCs.

Mech Ageing Dev, 2003 Apr, 124(4), 419 - 25
Neutrophil immunity of the elderly; Schroder AK et al.; Due to age-related changes of the immune system, elderly people are more susceptible to microbial infections than the young . Most research concerning immune senescence has been done on T and B cells, yet the first cells to migrate into microbe-infected tissue are neutrophils, which phagocytose and kill the pathogens . Long regarded as mere phagocytes, the neutrophils' importance for the immune response has been recognized in current publications, which acknowledge them an active participation in the cytokine network . Similarities in the symptoms of patients with genetical neutrophil deficiencies and those of the elderly indicate a leading role of neutrophils in the effects of immune senescence . While the number of circulating neutrophils remains unaltered in the elderly compared with young controls, phagocytosis and intracellular killing have been reported impaired . Oddly enough, the results for various stimuli differed: while some showed a decrease in neutrophil activation, the response to others remained unaltered . More research needs to be done on this, preferably using preparations of high purity to exclude monocytic interventions . Elucidation of immune deficiencies caused by neutrophil senescence can be an important contribution to a healthier elderly population.

Curr Opin Chem Biol, 2003 Apr, 7(2), 160 - 5
Microbe-metal interactions in marine hydrothermal environments; Holden JF et al.; Marine hydrothermal microorganisms respond rapidly to changes in the concentrations and availability of metals within their environment . Hyperthermophilic archaea appear to possess novel mechanisms for metal detoxification, dissimilatory metal reduction and metal assimilation that may be absent in their mesophilic and bacterial counterparts . For example, tungsten was found in high concentrations in a hydrothermal sulfide deposit where hyperthermophiles were also most abundant, consistent with the unique requirement of these organisms for this element . Furthermore, newly isolated genera of iron-reducing hyperthermophiles expand the scope of carbon cycling in hydrothermal environments . The advent of genome sequences and new molecular techniques will facilitate our further understanding of microbe-mineral interactions in these environments.

Calcif Tissue Int, 2003 May, 72(5), 567 - 76 Epub 2003 Apr 28.
Mineralized microstructure of calcified avian tendons: a scanning small angle X-ray scattering study; Gupta HS et al.; The micrometer level spatial distribution of the size, shape, and orientation of mineral crystallites in the calcifying matrix of tendons near the edge of the mineralizing front was investigated by scanning small angle X-ray scattering using synchrotron X-ray radiation . Using a special microbeam arrangement enabling 20 microm beam resolution and short measurement times, linear diffraction scans were made on sections from the normally calcifying tendons (tibialis cranialis) from the domestic turkey, which calcify in the distal to proximal direction . A change in shape and arrangement of mineral crystals was observed within the first 200 microm of the mineralization front, and the mineral crystal distribution was highly anisotropic with crystals aligned parallel to the fiber axis . In a cross-section of the tendon cut at right angles to the fiber axis, the orientation distribution of crystals was not azimuthally symmetric, and showed a small but nonzero anisotropy and a continuous change in mean orientation angle across the width of the tendon cross-section.

Arch Environ Contam Toxicol, 2003 May, 44(4), 493 - 501
Assessment of white blood cell phagocytosis as an immunological indicator of methylmercury exposure in birds; Holloway J et al.; White blood cell (WBC) phagocytosis was investigated as a potential immunological indicator of methylmercury (MeHg) exposure in birds . The assay was first assessed using chicken WBCs dosed with MeHg in vitro either in whole blood or as isolated cells and later using blood of wild common loons exposed in vivo to a range of dietary MeHg and having a range of blood-Hg concentrations . Whole blood and isolated WBCs from captive chickens were exposed to a range of MeHg concentrations for 3 h . After MeHg exposure, cells were incubated with fluorescent latex microbeads (diameter = 1.75 microm), fixed, and analyzed for size, complexity, and fluorescent intensity by flow cytometry . MeHg significantly depressed phagocytic activity when added to isolated WBCs at concentrations > 0.01 microg/ml, but not when added to whole blood up to 50 microg/ml . Similarly, no significant relationship between the concentration of Hg in whole blood and phagocytic capacity of WBCs in free-living loons was observed . Our results suggest that the phagocytosis assay, although rapid and convenient for use in field studies with wildlife species, is not a responsive immunological indicator of MeHg exposure at environmentally realistic concentrations of blood-Hg in wild loons . Assays that measure other immunologic endpoints (e.g., bacterial killing assay, PHA skin test, and mitogen-induced lymphocyte proliferation) should be assessed with respect to their ability to detect MeHg immunotoxicity in wild birds.

Radiat Res, 2003 May, 159(5), 632 - 41
Murine EMT-6 carcinoma: high therapeutic efficacy of microbeam radiation therapy; Dilmanian FA et al.; Microbeam radiation therapy is an experimental modality using parallel arrays of thin (<100 micro m) slices of synchrotron-generated X rays (microplanar beams, microbeams) . We used EMT-6 murine mammary carcinoma subcutaneously inoculated in the hind legs of mice to compare the therapeutic efficacies of single-fraction, unidirectional (1) "co-planar" microbeams (an array of vertically oriented microplanar beams), (2) "cross-planar" microbeams (two arrays of parallel microbeams propagated in the same direction, one with vertically and the other with horizontally oriented microplanar beams), and (3) seamless (broad) beams from the same synchrotron source . The microbeams were 90 micro m wide and were spaced 300 micro m on center; the median energy in all beams was 100 or 118 keV . Tumor ablation rates were 4/8, 4/8 and 6/7 for a 410-, 520- and 650-Gy in-slice cross-planar microbeam dose, respectively, and 1/8, 3/8, 3/7 and 6/8 for a 23-, 30-, 38- and 45-Gy broad-beam dose, respectively . When the data were pooled from the three highest doses (same average tumor ablations of 50-60%), the incidences of normal-tissue acute toxicity (moist desquamation and epilation) and delayed toxicity (failure of hair regrowth) were significantly lower for cross-planar microbeams than broad beams (P < 0.025) . Furthermore, for the highest doses in these two groups, which also had the same tumor ablation rate (>75%), not only were the above toxicities lower for the cross-planar microbeams than for the broad beams (P < 0.02), but severe leg dysfunction was also lower (P < 0.003) . These findings suggest that single-fraction microbeams can ablate tumors at high rates with relatively little normal-tissue toxicity.

Biosens Bioelectron, 2003 May, 18(5-6), 521 - 7
Taxonomic identification of microorganisms by capture and intrinsic fluorescence detection; Mason HY et al.; Quick and accurate detection of microbial contamination is accomplished by a unique combination of leading edge technologies described in this and the accompanying article . Microbe capture chips, used with a prototype fluorescence detector, are capable of statistically sampling the environment for pathogens (including spores), identifying the specific pathogens/exotoxins, and determining cell viability where appropriate.

Biosens Bioelectron, 2003 May, 18(5-6), 511 - 9
Reagentless detection of microorganisms by intrinsic fluorescence; Estes C et al.; Quick and accurate detection of microbial contamination is accomplished by a unique combination of leading-edge technologies described in this and the accompanying paper . In this contribution, a hand-held prototype instrument is described which is capable of statistically sampling the environment for microbial contamination and determining cell viability . The technology is sensitive enough to detect very low levels ( approximately 20 cells/cm(2) or cm(3)) of microbes in seconds.

Arch Biochem Biophys, 2003 May 1, 413(1), 41 - 52
Macrophage recognition of externalized phosphatidylserine and phagocytosis of apoptotic Jurkat cells--existence of a threshold; Borisenko GG et al.; Phosphatidylserine (PS) is predominantly confined to the inner leaflet of plasma membrane in cells, but it is externalized on the cell surface during apoptosis . This externalized PS is required for effective phagocytosis of apoptotic cells by macrophages . Because PS trans-bilayer asymmetry is not absolute in different types of nonapoptotic cells, we hypothesized that the amounts of externalized PS may be critical for macrophage discrimination between apoptotic and nonapoptotic cells . We developed a sensitive electron paramagnetic resonance method to quantify the amounts of externalized PS based on specific binding of paramagnetic annexin V-microbead conjugates with PS on cell surfaces . Using this technique, we found that nonapoptotic Jurkat cells externalize 0.9 pmol of endogenous PS/10(6) Jurkat cells . For cells with different amounts of integrated exogenous PS on their surface, no phagocytic response was observed at PS levels <5 pmol/10(6) Jurkat cells; at higher PS concentrations, phagocytosis increased in a concentration-dependent manner . Apoptosis in Jurkat cells caused externalization of approximately 240 pmol PS/10(6) Jurkat cells; these amounts of externalized PS are manyfold higher than the threshold amounts of PS required for phagocytosis . Thus, macrophages have a sensitivity threshold for PS externalized on the cell surface that provides for reliable recognition and distinction between normal cells with low contents of externalized PS and apoptotic cells with remarkably elevated PS levels.

Nature, 2003 Apr 17, 422(6933), 711 - 3
Soil invertebrate fauna enhances grassland succession and diversity; De Deyn GB et al.; One of the most important areas in ecology is to elucidate the factors that drive succession in ecosystems and thus influence the diversity of species in natural vegetation . Significant mechanisms in this process are known to be resource limitation and the effects of aboveground vertebrate herbivores . More recently, symbiotic and pathogenic soil microbes have been shown to exert a profound effect on the composition of vegetation and changes therein . However, the influence of invertebrate soil fauna on succession has so far received little attention . Here we report that invertebrate soil fauna might enhance both secondary succession and local plant species diversity . Soil fauna from a series of secondary grassland succession stages selectively suppress early successional dominant plant species, thereby enhancing the relative abundance of subordinate species and also that of species from later succession stages . Soil fauna from the mid-succession stage had the strongest effect . Our results clearly show that soil fauna strongly affects the composition of natural vegetation and we suggest that this knowledge might improve the restoration and conservation of plant species diversity.

Toxicol Sci, 2003 May, 73(1), 53 - 9 Epub 2003 Apr 15.
Androstenedione and progesterone in the sediment of a river receiving paper mill effluent; Jenkins RL et al.; The Fenholloway River near Perry, Florida, receives effluent from a paper mill and contains populations of masculinized female eastern mosquitofish, Gambusia holbrooki . A previous study identified the androgen precursor androstenedione at a low concentration (0.14 nM) in water samples from the river . The present study makes use of a toxicity identification and evaluation approach that includes solid phase extraction and high pressure liquid chromatography purification, androgen receptor transcription assays, and liquid chromatography mass spectroscopy to identify and characterize steroids in the Fenholloway River sediment . Androstenedione (2.4 nM) and progesterone (155 nM) were identified in the river sediment at concentrations greater than in the river water column (0.14 nM androstenedione, and 6.5 nM progesterone) . Spring Creek, a comparison stream that does not receive mill effluent, contained low levels of progesterone (0.3 nM) but no androstenedione in the sediment . The data are consistent with the hypothesis that pine pulp-derived phytosteroids in the paper mill effluent accumulate in river sediment where they are converted by microbes into progesterone and this into androstenedione and other bioactive steroids . Equally important is that normal streams with much less organic matter still contain progesterone, but at dramatically lower levels . The presence of androgens and androgen precursors in the river water and sediment likely contributes to the masculinized phenotype of the female Gambusia holbrooki in the Fenholloway River.

Front Biosci, 2003 May 01, 8, d963 - 81
Repair mechanisms for oxidative DNA damage; Wilson DM 3rd et al.; Reactive oxygen species are formed as by-products of mitochondrial aerobic respiration, as induced products upon exposure to certain environmental/exogenous agents (e.g . ionizing radiation), or as intended products during the immune response against invading foreign microbes . Although serving as essential signaling molecules in certain biological processes (e.g . during gene activation responses), these chemicals, particularly during oxidative stress when at excessive concentrations, can react with cellular components, most notably DNA, and in this capacity, promote mutagenesis or cell death, and in turn, human disease . We review here several of the common oxidative DNA damages as well as the DNA repair mechanisms related to maintaining genome integrity, and thus, preventing cancer formation and age-related disease . We focus mainly on participants of the base excision repair (BER) pathway . In brief, the steps of BER include: (a) excision of the damaged base, (b) incision of the DNA backbone at the apurinic/apyrimidinic (AP) site product, (c) removal of the AP terminal fragment, (d) gap-filling synthesis, and (e) ligation of the final nick.

Toxicology, 2003 May 3, 187(2-3), 195 - 203
Low-level sarin-induced alteration of immune system reaction in inbred BALB/c mice; Kassa J et al.; To study the influence of low-level sarin inhalation exposure on immune functions, inbred BALB/c mice were exposed to low concentrations of sarin for 60 min in the inhalation chamber . Two concentrations of sarin were chosen-asymptomatic concentration (LEVEL 1) and non-convulsive symptomatic concentration (LEVEL 2) . The evaluation of immune functions was carried out using phenotyping of CD3 (T-lymphocytes), CD4 (helper T-lymphocytes), CD8 (cytotoxic T-lymphocytes) and CD19 cells (B-lymphocytes) in the lungs, blood and spleen, lymphoproliferation of spleen cells stimulated in vitro by various mitogens (concanavalin A, lipopolysaccharides), phagocyte activity of peritoneal and alveolar macrophages, production of N-oxides by peritoneal macrophages and the measurement of the natural killer cell activity at 1 week following sarin exposure . The results were compared to the values obtained from control mice exposed to pure air instead of sarin . The results indicate that not only symptomatic but also asymptomatic dose of sarin is able to alter the reaction of immune system at 1 week following exposure to sarin . While the number of CD3 cells in the lungs was slightly decreased, an increase in CD19 cells was observed especially in the lungs and blood . The reduced proportion of T-lymphocytes is caused by decay of CD4 positive T-cells . Lymphoproliferation was significantly decreased regardless of the mitogen and sarin concentration used . The production of N-oxides by peritoneal macrophages was stimulated after exposure to LEVEL 2 of sarin whereas their ability to phagocyte the microbes was increased after exposure to LEVEL 1 . The natural killer cell activity was significantly higher in the case of inhalation exposure of mice to LEVEL 2 of sarin . Thus, not only organophosphorus insecticides but also nerve agents such as sarin are able to alter immune functions even at a dose that does not cause clinically manifested intoxication following the inhalation exposure . Nevertheless, the alteration of immune functions following the inhalation exposure to a symptomatic concentration of sarin seems to be more pronounced.

Br J Haematol, 2003 Apr, 121(2), 240 - 50
Generation of dendritic cells from CD14+ monocytes positively selected by immunomagnetic adsorption for multiple myeloma patients enrolled in a clinical trial of anti-idiotype vaccination; Motta MR et al.; Circulating monocytes from multiple myeloma patients enrolled in a clinical study of anti-idiotype vaccination were labelled with clinical-grade anti-CD14 microbeads and positively selected with the CliniMACS instrument . Cells were then grown, according to good manufacturing practice guidelines, in fetal-calf-serum-free medium in cell culture bags and differentiated to dendritic cells (DC) with granulocyte-macrophage colony stimulating factor plus interleukin 4 (IL-4), followed by either tumour necrosis factor-alpha (TNF-alpha) or a cocktail of IL-1beta, IL-6, TNF-alpha and prostaglandin-E2 . The CD14+ cell yield was increased from 17.6 +/- 6.5% to 93.8 +/- 6.3% (recovery 64.4 +/- 15.4%, viability > 97%) . After cell culture, phenotypic analysis showed that 86.7 +/- 6.8% of the cells were DC: 2.27 +/- 0.9 x 108 DC/leukapheresis were obtained, which represented 20.7 +/- 4.6% of the initial number of CD14+ cells . Notably, the cytokine cocktail induced a significantly higher percentage and yield (28.6 +/- 3% of initial CD14+ cells) of DC than TNF-alpha alone, with secretion of larger amounts of IL-12, potent stimulatory activity on allogeneic T cells and efficient presentation of tumour idiotype to autologous T cells . Storage in liquid nitrogen did not modify the phenotype or functional characteristics of preloaded DC . The recovery of thawed, viable DC was 78 +/- 10% . Finally, interferon-alpha-2b was at least as efficient as IL-4 in inducing the differentiation of mature, functional DC from monocytes.

Clin Microbiol Rev, 2003 Apr, 16(2), 209 - 19
Microbial infections, immunomodulation, and drugs of abuse; Friedman H et al.; The use of recreational drugs of abuse has generated serious health concerns . There is a long-recognized relationship between addictive drugs and increased levels of infections . Studies of the mechanisms of actions of these drugs became more urgent with the advent of AIDS and its correlation with abused substances . The nature and mechanisms of immunomodulation by marijuana, opiates, cocaine, nicotine, and alcohol are described in this review . Recent studies of the effects of opiates or marijuana on the immune system have demonstrated that they are receptor mediated, occurring both directly via specific receptors on immune cells and indirectly through similar receptors on cells of the nervous system . Findings are also discussed that demonstrate that cocaine and nicotine have similar immunomodulatory effects, which are also apparently receptor mediated . Finally, the nature and mechanisms of immunomodulation by alcohol are described . Although no specific alcohol receptors have been identified, it is widely recognized that alcohol enhances susceptibility to opportunistic microbes . The review covers recent studies of the effects of these drugs on immunity and on increased susceptibility to infectious diseases, including AIDS.

Science, 2003 Apr 11, 300(5617), 290 - 3
Realizing the potential of the genome revolution: the genomes to life program; Frazier ME et al.; The systems biology revolution is proceeding along multiple pathways as different science agencies and the private sector have adopted strategies suited to their particular needs and cultures . To meet this challenge, the U.S . Department of Energy has developed the Genomes to Life (GTL) program . A central focus of GTL is environmental microbial biology as a way to approach global environmental problems, and its key goal is to achieve, over the next 10 to 20 years, a basic understanding of thousands of microbes and microbial systems in their native environments . This focus demands that we address huge gaps in knowledge, technology, computing, data storage and manipulation, and systems-level integration.

Chemosphere, 2003 Feb, 50(6), 683 - 7
Organo-chlorine pesticide (DDT and HCH) residues in the Taihu Lake Region and its movement in soil-water system I . Field survey of DDT and HCH residues in ecosystem of the region; Feng K et al.; The use of organo-chlorine (DDT and HCH) has been banned in China for 20 years . A field survey was carried out during 1999-2000 in the Taihu Lake Region . Organo-chlorine pesticide (OCP) residues in soil, water, fish and sediment samples were investigated . DDT was detected in 5 out of 10 samples with concentration ranging from 0.3 to 5.3 microg/kg in the surface (0-15 cm) layer, 6 out of 10 with 0.5 to 4.0 microg/kg in the subsoil layer (16-30 cm), and 4 of 10 with 0 to 2.7 microg/ kg in the deep soil layer (31-50 cm) . Results for HCH residues in soil samples were similar to those of DDT . These results indicate that OCP residues in 0-50 cm profile had been leached out or degraded to safe level . In river water DDT was detected in 10 out of 13 samples ranging from 0.2 to 9.3 microg/l, with an average of 1.0 microg/l . While HCH was detected in 12 out of 13 samples ranging from 0.02 to 36.1 microg/l, with an average 5.6 microg/l . DDT residues in sediment ranged from 0.1 to 8.8 microg/kg, while HCH ranged from 0.3 to 66.5 microg/kg . DDT residues in fish body ranged from 3.7 to 23.5 microg/kg and HCH ranged from 3.7 to 132 microg/kg . These results demonstrate an accumulation through food chain (from soil-water-sediment-microbes-crop-fish-.. . etc.), also that HCH residues are generally more persistent than DDT residues . However, all these data are well below than the state warning standard limit.

Planta, 2003 Apr, 216(6), 891 - 902 Epub 2003 Feb 11.
Reactive oxygen intermediates in plant-microbe interactions: who is who in powdery mildew resistance?
Huckelhoven R, Kogel KH.
Reactive oxygen intermediates (ROIs) such as hydrogen peroxide (H(2)O(2)) and the superoxide anion radical (O*(2)(-)) accumulate in many plants during attack by microbial pathogens . Despite a huge number of studies, the complete picture of the role of ROIs in the host-pathogen interaction is not yet fully understood . This situation is reflected by the controversially discussed question as to whether ROIs are key factors in the establishment and maintenance of either host cell inaccessibility or accessibility for fungal pathogens . On the one hand, ROIs have been implicated in signal transduction as well as in the execution of defence reactions such as cell wall strengthening and a rapid host cell death (hypersensitive reaction) . On the other hand, ROIs accumulate in compatible interactions, and there are reports suggesting a function of ROIs in restricting the spread of leaf lesions and thus in suppressing cell death . Moreover, in situ analyses have demonstrated that different ROIs may trigger opposite effects in plants depending on their spatiotemporal distribution and subcellular concentrations . This demonstrates the need to determine the particular role of individual ROIs in distinct stages of pathogen development . The well-studied interaction of cereals with fungi from the genus Blumeria is an excellent model system in which signal transduction and defence reactions can be further elucidated in planta . This review article gives a synopsis of the role of ROI accumulation, with particular emphasis on the pathosystem Hordeum vulgare L.- Blumeria graminis.

Russ J Immunol, 1999 Oct, 4(3), 220 - 223
Cells of Immune System: Development, Activation, Effector Functions; Freidlin IS; While understanding the role of certain cell populations and subpopulations is being more precisely identified, the pool of immunocompetent cells becomes continuously broader . It has rather recently been shown that hematopoietic precursors that express CD34 on their surface may be served as precursors of both monocytes/macrophages (Mn/Mf), and dendritic cells (DC) Huge experimental data obtained for recent years have shown that DC may just be comprehensive APC, capable to present both bacterial, and viral antigens in both primary, and secondary immune response for recognition by both T helpers (CD4(+)) and cytotoxic T lymphocytes (CD8(+)) . Both Mf, and DC are producers of cytokines . After microbe phagocytosis by Mf or after DC infection, microbe components may induce production of IL-12 in these cells followed by IL-12 induction of IFNgamma production in NK and CD4(+) T lymphocytes . IFNgamma production is highly inducible: primary steps of IFNgamma production require, at least, two activation signals: from TCR, from adhesive or costimulatory molecules or from receptor for any additional cytokine, for example, IL-12 . IFNgamma is synergistic agent for IL-12 that is providing costimulatory signal in induction of Th1 differentiation and is enhancing the sensitivity of naive T lymphocytes to stimulatory action of IL-12 . Either Th1, and Th2 express beta1-chain of IL-12 receptor, but only Th1 express beta2-chain of this receptor . Incapability of Th2 to respond to IL-12 by activation is related to such a situation.

Oncogene, 2003 Apr 10, 22(14), 2097 - 109
Involvement of nectin in the localization of IQGAP1 at the cell-cell adhesion sites through the actin cytoskeleton in Madin-Darby canine kidney cells; Katata T et al.; IQGAP1, a putative downstream target of the Rho family small G proteins, Cdc42 and Rac, localizes at adherens junctions (AJs) in epithelial cells . It has been suggested that IQGAP1 localizes at AJs through its binding to beta-catenin, and negatively regulates the E-cadherin-mediated cell-cell adhesion . Nectin is a Ca(2+)-independent, immunoglobulin-like cell-cell adhesion molecule that localizes at AJs . Nectin is associated with E-cadherin through their respective cytoplasmic tail-binding proteins, afadin and catenins, and involved in the formation of AJs cooperatively with E-cadherin . Here we investigated a role of nectin in the localization of IQGAP1 at AJs . Ca(2+) chelation from the medium causes disruption of the E-cadherin-mediated cell-cell adhesion, but not the nectin-based cell-cell adhesion, in Madin-Darby canine kidney (MDCK) cells . IQGAP1 remained at the residual nectin-based cell-cell adhesion sites where the E-cadherin immunofluorescence signal disappeared . Restoration of Ca(2+) in the medium causes re-accumulation of E-cadherin to the residual nectin-based cell-cell adhesion sites to re-form AJs . Nectin inhibitors inhibit this re-accumulation of E-cadherin to re-form AJs by impairing the nectin-based cell-cell adhesion . The nectin inhibitors also reduced the localization of IQGAP1 at the cell-cell adhesion sites . When MDCK cells were incubated with microbeads coated with the extracellular fragment of nectin that interacts with cellular nectin, IQGAP1 also accumulated at the bead-MDCK cell contact sites . The accumulation of IQGAP1 at the cell-cell adhesion sites was inhibited by actin filament-disrupting agents, latrunculin A and cytochalasin D . These results indicate that nectin is involved in the localization of IQGAP1 at AJs through the actin cytoskeleton.

Trends Genet, 2003 Apr, 19(4), 224 - 31
pH regulation in Aspergillus and parallels with higher eukaryotic regulatory systems; Arst HN et al.; All organisms respond to their environment to some extent, and for many microbes the variation in environment can be enormous . An important asset for coping with environmental variation is physiological versatility--a hallmark of many fungi . The ability of fungi to thrive over a wide range of pH is partly due to a genetic regulatory system that tailors gene expression to the ambient pH . Here we focus on the pH regulatory system of Aspergillus nidulans, where a novel signal transduction (pal) pathway mediates the first of two steps in the proteolytic processing of a transcription factor (PacC) . Such processing is reminiscent of that of some well-known higher eukaryotic transcription factors, such as Cubitus interruptus, NF-kappa B and sterol regulatory element binding proteins . Intriguingly, endocytosis seems to be connected to pH signalling.

Curr Pharm Des, 2003, 9(11), 879 - 89
Enhancing marine natural product structural diversity and bioactivity through semisynthesis and biocatalysis; Hamann MT; In the last several decades the plants, animals and microbes from the marine environment have revealed a portion of what is clearly a tremendous resource for structurally diverse and bioactive secondary metabolites . Many of these extraordinarily sophisticated and bioactive natural products can be isolated in significant quantities without great difficulty . As a result these readily available bioactive natural products provide valuable starting materials for the rational generation of libraries of compounds prepared through semisynthesis and biocatalysis . A review of our work using marine natural products to generate rationally designed compound libraries and their biological activity against infectious diseases, cancer and neurological targets is presented . The marine natural products utilized to date as starting materials consist of compounds from a variety of structural classes and include: aureol, puupehenone, sarcophine, palinurin, and the manzamine alkaloids . The possibility to generate diverse bioactive products beginning with a marine natural product scaffold is a direct result of improvements made in the technologies to harvest samples from the ocean, purify and characterize complex natural products quickly and complete chemical reactions and biotransformations in parallel . As a result the vast resources of the ocean can now be utilized routinely to design and produce countless products to be evaluated as part of drug discovery and development programs.

Am Surg, 2003 Mar, 69(3), 231 - 7; discussion 237
The effects of varying oxygen conditions and immunoglobulin A on barrier defense to bacterial invasion; Baylor AE et al.; Tissue oxygenation is a critical factor in host defense against bacteria . Gut mucosal tissue oxygenation (partial pressure of O2) is normally low putting the gut at risk of invasion by luminal microbes . Secretory immunoglobulin (Ig) A (sIgA) is the principal immune defense at mucosal surfaces . The protective effect of IgA under low oxygen conditions is unknown . We studied the interaction of varying O2 environments and sIgA on protection against bacterial invasion in our in vitro model . Cell monolayers of Madin-Darby canine kidney (MDCK) cells transfected with the cDNA for polymeric immunoglobulin receptor were established in a two-chamber cell culture system . A commensal strain of Escherichia coli (10(8) colony-forming units) was added to the apical medium and cell cultures were placed in either a 5, 21, or 95 per cent O2 environment at 37 degrees C . Polyclonal sIgA (100 microg/mL) was added to the apical chamber in subsets . Basal medium was sampled at intervals and bacterial translocation quantitated . The cell monolayers of MDCK transfected cells then had 100 microg/mL IgA added to the basal compartment at 4 degrees C for 2 hours followed by various oxygen environments for 90 minutes . Afterwards apical medium was removed at one, 3, and 12 (overnight) hours . The bacterial translocation data showed a significance increase in translocation with hypoxia . Both increased oxygen and IgA abrogated these effects significantly . The transcytosis of IgA was increased during hypoxic conditions . Normal and hyperoxic conditions did not produce any significant difference in IgA transcytosis . We conclude that O2 and sIgA are protective against bacterial invasion at epithelial surfaces . Effects to either boost O2 delivery to the gut or enhance mucosal IgA production and delivery may be protective in the critically ill surgical patient.

Appl Environ Microbiol, 2003 Apr, 69(4), 2340 - 8
A new rate law describing microbial respiration; Jin Q et al.; The rate of microbial respiration can be described by a rate law that gives the respiration rate as the product of a rate constant, biomass concentration, and three terms: one describing the kinetics of the electron-donating reaction, one for the kinetics of the electron-accepting reaction, and a thermodynamic term accounting for the energy available in the microbe's environment . The rate law, derived on the basis of chemiosmotic theory and nonlinear thermodynamics, is unique in that it accounts for both forward and reverse fluxes through the electron transport chain . Our analysis demonstrates how a microbe's respiration rate depends on the thermodynamic driving force, i.e., the net difference between the energy available from the environment and energy conserved as ATP . The rate laws commonly applied in microbiology, such as the Monod equation, are specific simplifications of the general law presented . The new rate law is significant because it affords the possibility of extrapolating in a rigorous manner from laboratory experiment to a broad range of natural conditions, including microbial growth where only limited energy is available . The rate law also provides a new explanation of threshold phenomena, which may reflect a thermodynamic equilibrium where the energy released by electron transfer balances that conserved by ADP phosphorylation.

J Appl Microbiol, 2003, 94 Suppl, 1S - 11S
The traveller and emerging infections: sentinel, courier, transmitter; Wilson ME; The movement of populations shapes the patterns and distribution of infectious diseases globally . The consequences of travel are seen in the traveller and in places and populations visited and may persist long after travel . The traveller can be seen as an interactive biological unit who picks up, processes, carries and drops off microbial genetic material . A traveller can introduce potential pathogens in the absence of signs or symptoms of illness . Travellers can serve as a sentinel population; study of them can provide insights into the presence and level of risk of transmission of infections in other geographical regions . Travellers can also be seen as couriers who inadvertently ferry pathogens and microbial genetic material to regions where researchers can carry out detailed analyses that can help to map the location and movement of strains, genotypes and resistance patterns . The laboratory plays a key role in the identification and characterization of pathogens, which can inform management of individual patients and the public health response . The connectedness and mobility in the world today facilitate the emergence of infectious diseases in humans and also in animals and plants . Many traditional barriers have been breached by travel, roads and technology . Population size and density favour spread of many infections . The rapid generation time of microbes and their capacity to adapt to changes in the physico-chemical and immunological environment will pose continuing challenges.

Pediatr Allergy Immunol, 2003 Apr, 14(2), 74 - 80
Immune deviation and the hygiene hypothesis: a review of the epidemiological evidence; Kemp A et al.; The epidemiological evidence for the proposal that early life immune deviation is the principal mechanism by which microbial agents prevent the development of atopy has been reviewed . Seven criteria are proposed which should ideally be fulfilled . The majority of studies only fulfill two or three criteria . For mycobacteria, measles and respiratory viruses there are studies that demonstrate a significant increase in atopy or allergic disease . Parasite infections, which provide a strong TH2 stimulus, are associated with reduced rather than enhanced allergen sensitization . The available epidemiological evidence does not provide support for a mechanism of early life immune deviation . The principal environmental influences on atopic disease are likely to occur throughout life and involve interactions between microbes and other non-infective and lifestyle factors.

Int J Colorectal Dis, 2003 May, 18(3), 181 - 7 Epub 2002 Nov 05.
The gut as an organ of immunology; Wittig BM et al.; BACKGROUND: In normal conditions human gut mucosa is infiltrated with a large number of mononuclear cells due to continuous stimulation by luminal antigens . This state of "physiological" inflammation is tightly controlled, as several mucosal cells interact to maintain an appropriate local immune response . Moreover, gut-associated lymphoid tissue must constantly distinguish harmless antigens that are present in food and on commensal bacteria from pathogenic microbes . INTERVENTIONS AND RESEARCH: The oral administration of soluble protein antigens induces a state of systemic immunological unresponsiveness specific to the fed protein, termed oral tolerance . The two major mechanisms to explain oral tolerance are anergy/deletion of autoreactive lymphocytes and active suppression . Changes in the pathways of immune activation are detected in chronic intestinal inflammation, such as inflammatory bowel disease or celiac disease . CONCLUSION: An appreciation of the current knowledge of the gut immune system is of importance for understanding and development of new treatment modalities in chronic intestinal inflammation.

Clin Oral Investig, 2003 Mar, 7(1), 38 - 40 Epub 2003 Mar 06.
Gingival colonization with selective HACEK microbes in children with congenital heart disease; Steelman R et al.; It was previously shown that children with congenital heart disease (CHD) harbored Hemophilus, Actinobacillus, Cardiobacter, Eikenella, and Kingella (HACEK) microbes to a greater extent and had more severe gingival inflammation than a normal group of children . The purpose of this study was to determine if HACEK microbes are more prevalent in children with CHD than in normal children when there is no difference in gingival inflammation . Two groups of 12 children were matched with respect to gingival inflammation . Each child had a gingival index recorded as described by Massler . The experimental group consisted of 12 children with CHD 2.5-10 years old (average 5.5) and the control group consisted of 12 healthy children 2-13 years old (average 5.6) . Subgingival samples were obtained and cultured for HACEK microbes . Fischer's exact test was performed with the significance level defined at P<0.05 . The average gingival indices for the experimental and control groups were 6.5 and 6.4, respectively (N.S.) . Nine of 12 children with CHD had Eikenella corrodens (E.c.) compared to 3/12 control patients ( P<0.05) . Three of 12 CHD patients but no control patient had Actinobacillus actinomycetemcomitans (A.a.) (N.S.) . There were no significant differences in E.c . or A.a . presence between cyanotic and acyanotic CHD patients . This study found that the greater extent of specific HACEK microbes harbored by children with CHD is not associated with cyanosis or the degree of gingival inflammation . Further study is needed to delineate fully the medical significance of this observation.

Nature, 2003 Apr 3, 422(6931), 531 - 4
The voltage dependence of NADPH oxidase reveals why phagocytes need proton channels; DeCoursey TE et al.; The enzyme NADPH oxidase in phagocytes is important in the body's defence against microbes: it produces superoxide anions (O2-, precursors to bactericidal reactive oxygen species) . Electrons move from intracellular NADPH, across a chain comprising FAD (flavin adenine dinucleotide) and two haems, to reduce extracellular O2 to O2- . NADPH oxidase is electrogenic, generating electron current (I(e)) that is measurable under voltage-clamp conditions . Here we report the complete current-voltage relationship of NADPH oxidase, the first such measurement of a plasma membrane electron transporter . We find that I(e) is voltage-independent from -100 mV to >0 mV, but is steeply inhibited by further depolarization, and is abolished at about +190 mV . It was proposed that H+ efflux mediated by voltage-gated proton channels compensates I(e), because Zn2+ and Cd2+ inhibit both H+ currents and O2- production . Here we show that COS-7 cells transfected with four NADPH oxidase components, but lacking H+ channels, produce O2- in the presence of Zn2+ concentrations that inhibit O2- production in neutrophils and eosinophils . Zn2+ does not inhibit NADPH oxidase directly, but through effects on H+ channels . H+ channels optimize NADPH oxidase function by preventing membrane depolarization to inhibitory voltages.

J Immunol Methods, 2003 Apr 1, 275(1-2), 149 - 60
Flow cytometry based detection of HLA alloantibody mediated classical complement activation; Wahrmann M et al.; Complement-dependent cytotoxicity (CDC) panel reactive antibody (PRA) testing is used to assess recipient presensitization and post-transplant alloantibody formation in transplant recipients . However, CDC test results can be affected by false-positive reactions brought about by autoantibodies or antilymphocyte reagents . As an alternative to the CDC-PRA assay, detection of HLA alloantibodies using HLA antigen-coated microbeads (FlowPRA test) was recently established . FlowPRA testing, however, does not distinguish between (presumably more harmful) complement-fixing and noncomplement-fixing alloantibodies . In this study, we established a novel assay allowing flow cytometric detection of HLA alloantibody dependent classical complement activation using the FlowPRA test . For the detection of complement activation, FlowPRA beads were incubated with sera from highly sensitized dialysis patients (CDC-PRA reactivity >60%) and then stained for C4 (C4d, C4c) and C3 (C3d, C3c) fragments, as well as C1q deposition using indirect immunofluorescence . We demonstrate alloantibody induced induction of C4 fragment, and in parallel C1q deposition to HLA class I or class II beads . As shown by immunoblotting, C4 staining was not due to the presence of preformed C4 fragment-IgG/M complexes . Indeed, C4 fragment deposition in our in vitro system was demonstrated to result from de novo complement activation . First, inactivation of C4 by treatment of sera with methylamine, which inhibits cleavage of the internal thioester, completely abolished C4 fragment deposition . Second, C4 fragment deposition was not observed in the evaluation of C4-free immunoadsorption eluates obtained from highly sensitized dialysis patients . After supplementation with complement, however, eluates induced C4 deposition . Deposition of C4 split products and C1q was temperature-dependent with maximum binding after incubation at 4 degrees C for 60 min . In contrast, maximum C3 fragment deposition was found at 37 degrees C . At this temperature, C3 deposition occurred in an alloantibody and C4-independent fashion, presumably as a result of alternative complement activation . In summary, we describe a novel cell-independent and easy-to-perform PRA test that permits flow cytometry based detection of alloantibody induced classical complement activation . Future studies will have to evaluate its possible relevance as an alternative to CDC-PRA testing in clinical transplantation.

J Immunol Methods, 2003 Apr 1, 275(1-2), 123 - 32
Analysis of intra-hepatic peptide-specific cell recruitment in mice immunised with Plasmodium falciparum antigens; Hebert A et al.; The liver stage of Plasmodium spp . now appears as a relevant target of immune effectors triggered by the so-called "anti-sporozoite" vaccine . Since the monitoring of immune responses at the systemic level may not faithfully reflect the local protective mechanisms, the aim of the present work was to set up a model to study the local intra-hepatic cellular responses and to compare these with the peripheral immune responses . This was achieved by intra-portal delivery of epitopic peptides, i.e . peptides containing B and T cell epitopes, which were coated onto the surface of polystyrene microbeads . The peptide-coated beads presumably mimic the hepatic schizont, and when distinct peptides are administered separately, this method of delivery allows us to decipher the immune responses resulting in mice immunised with recombinant proteins spanning several such epitopes . Using the P . falciparum liver stage antigen-3 (LSA3) molecule, which can induce protection against a sporozoite challenge, our results show that 25-microm microbeads could easily access the liver parenchyma by intra-portal injection and were distributed evenly in the liver . Also, LSA3-derived synthetic peptides coated onto microbeads initiated specific cell recruitment within 6 h . Depending on the LSA3 peptide used, the infiltrates induced differed in size, with the strongest cell recruitment obtained using nonrepeat II peptide (NR2)-coated microbeads with a mean leukocyte number of 79 per granuloma . Immunohistological studies of liver sections revealed that, irrespective of the delivered peptide, cells infiltrating the liver towards microbeads were mainly CD3(+) T lymphocytes, both CD4(+) (70 to 80%) and CD8(+) (20 to 30%) subtypes, macrophages and dendritic cells . Cells infiltrating the granuloma had features of activated cells, with evidence of VLA-4 cell-surface expression, and production of IFN-gamma and IL-4 . Analysis of the peripheral B and T-cell responses in the same animals revealed that, whereas the local responses were directed mainly towards NR2 and repeat peptides (RE), the peripheral T-cell response to these peptides was weak and infrequent, although antibody production was high.

Mikrobiol Z, 2002 Nov-Dec, 64(6), 62 - 6
{Effect of various anions on the rate of microbe-induced corrosion}; Piliashenko-Novokhatnyi AI et al.; Experimental corroboration of correctness of theoretical thermodynamic calculations of e.m.f . of corrosion reactions induced by soil microorganisms is obtained in the work . A hypothesis is put forward on possible mechanism for stimulation of microbe-induced corrosion by chloride ions . The results obtained permit revealing the reasons of low efficiency conditions of cathode protection in cases of active involvement of soil microorganisms into corrosion processes which are used for maintenance of underground constructions.

J Perinat Med, 2003, 31(1), 69 - 74
CSF findings in neonates with seizures; infectious and noninfectious; Mustonen K et al.; In order to evaluate parameters of cerebrospinal fluid (CSF) we studied 105 CSF samples of 50 neonates with seizures of unknown origin for cell count and chemistry (protein, albumin, glucose, IgG-index and albumin-ratio) . Viral studies for 13 different microbes were performed from serum and CSF . CSF parameters of the babies with a suggested viral infection (n = 13) were compared with those without any viral findings (n = 37), and followed up to the age 45 weeks since conception . CSF mononuclear white blood cell count was < or = 20 x 10(6)/l at the age of < or = 40 weeks since conception, and thereafter i.e . at term it was < or = 10 x 10(6)/l in all neonates without viral infection, whereas mononuclear cell count was above these limits in 8 of 13 neonates with viral infection . The rate of IgG-index remained high only in the neonates with a viral infection when studied at the age of over 43 weeks since conception . We conclude that studies of CSF are a valuable diagnostic aid in CNS viral infections of neonates when evaluated in reference to the age since conception, and the limits of mononuclear white blood cells in normal CSF of neonates are in lower limits than reported before.

Genomics, 2003 Mar, 81(3), 329 - 35
Pathogen discovery from human tissue by sequence-based computational subtraction; Xu Y et al.; We have recently reported a new pathogen discovery approach, "computational subtraction" . With this approach, non-human transcripts are detected by sequencing cDNA libraries from infected tissue and eliminating those transcripts that match the human genome . We show now that this method is experimentally feasible . We generated a cDNA library from a tissue sample of post-transplant lymphoproliferative disorder (PTLD) . 27,840 independent cDNA sequences were filtered by computational subtraction against the known human sequence to identify 32 nonmatching transcripts . Of these, 22 (0.1%) were found to be amplifiable from both infected and noninfected samples and were inferred to be human DNA not yet contained in the available human genome sequence . The remaining 10 sequences could be amplified only from Epstein-Barr virus (EBV)-infected tissues . All 10 corresponded to the known EBV sequence . This proof-of-principle experiment demonstrates that computational subtraction can detect pathogenic microbes in primary human-diseased tissue.

Appl Microbiol Biotechnol, 2003 Mar, 61(1), 21 - 31 Epub 2002 Dec 24.
Biotin in microbes, the genes involved in its biosynthesis, its biochemical role and perspectives for biotechnological production; Streit WR et al.; Biotin (vitamin H) is one of the most fascinating cofactors involved in central pathways in pro- and eukaryotic cell metabolism . Since its original discovery in 1901, research has led to the discovery of the complete biotin biosynthesis pathways in many different microbes and much work has been done on the highly intriguing and complex biochemistry of biotin biosynthesis . While humans and animals require several hundred micrograms of biotin per day, most microbes, plants and fungi appear to be able to synthesize the cofactor themselves . Biotin is added to many food, feed and cosmetic products, creating a world market of 10-30 t/year . However, the majority of the biotin sold is synthesized in a chemical process . Since the chemical synthesis is linked with a high environmental burden, much effort has been put into the development of biotin-overproducing microbes . A summary of biotin biosynthesis and its biological role is presented; and current strategies for the improvement of microbial biotin production using modern biotechnological techniques are discussed.

Glycobiology, 2003 Jul, 13(7), 41R - 53R Epub 2003 Mar 19.
Fucose: biosynthesis and biological function in mammals; Becker DJ et al.; Fucose is a deoxyhexose that is present in a wide variety of organisms . In mammals, fucose-containing glycans have important roles in blood transfusion reactions, selectin-mediated leukocyte-endothelial adhesion, host-microbe interactions, and numerous ontogenic events, including signaling events by the Notch receptor family . Alterations in the expression of fucosylated oligosaccharides have also been observed in several pathological processes, including cancer and atherosclerosis . Fucose deficiency is accompanied by a complex set of phenotypes both in humans with leukocyte adhesion deficiency type II (LAD II; also known as congenital disorder of glycosylation type IIc) and in a recently generated strain of mice with a conditional defect in fucosylated glycan expression . Fucosylated glycans are constructed by fucosyltransferases, which require the substrate GDP-fucose . Two pathways for the synthesis of GDP-fucose operate in mammalian cells, the GDP-mannose-dependent de novo pathway and the free fucose-dependent salvage pathway . In this review, we focus on the biological functions of mammalian fucosylated glycans and the biosynthetic processes leading to formation of the fucosylated glycan precursor GDP-fucose.

Tree Physiol, 1998 Oct, 18(10), 665 - 670
Variation in sugar maple root respiration with root diameter and soil depth; Pregitzer KS et al.; Root respiration may account for as much as 60% of total soil respiration . Therefore, factors that regulate the metabolic activity of roots and associated microbes are an important component of terrestrial carbon budgets . Root systems are often sampled by diameter and depth classes to enable researchers to process samples in a systematic and timely fashion . We recently discovered that small, lateral roots at the distal end of the root system have much greater tissue N concentrations than larger roots, and this led to the hypothesis that the smallest roots have significantly higher rates of respiration than larger roots . This study was designed to determine if root respiration is related to root diameter or the location of roots in the soil profile . We examined relationships among root respiration rates and N concentration in four diameter classes from three soil depths in two sugar maple (Acer saccharum Marsh.) forests in Michigan . Root respiration declined as root diameter increased and was lower at deeper soil depths than at the soil surface . Surface roots (0-10 cm depth) respired at rates up to 40% greater than deeper roots, and respiration rates for roots < 0.5 mm in diameter were 2.4 to 3.4 times higher than those for roots in larger diameter classes . Root N concentration explained 70% of the observed variation in respiration across sites and size and depth classes . Differences in respiration among root diameter classes and soil depths appeared to be consistent with hypothesized effects of variation in root function on metabolic activity . Among roots, very fine roots in zones of high nutrient availability had the highest respiration rates . Large roots and roots from depths of low nutrient availability had low respiration rates consistent with structural and transport functions rather than with active nutrient uptake and assimilation . These results suggest that broadly defined root classes, e.g., fine roots are equivalent to all roots < 2.0 mm in diameter, do not accurately reflect the functional categories typically associated with fine roots . Tissue N concentration or N content (mass x concentration N) may be a better indicator of root function than root diameter.

J Lab Clin Med, 2003 Mar, 141(3), 229 - 30
Nobel prize winner trading card (CIRCA 1952) . Elie Metchnikoff; Hammerschmidt DE; Russian doctor and bacteriologist, born in Ivanowca in 1845 . He began his studies in Kharkov, continuing them at the Universities of Giessen, Gothingen, and Munich, later being named Professor of Zoology in Odessa in 1870 . In the Canary Islands, he completed some anthropological works, but dedicated himself especially to studies of marine fauna . In 1887, much taken by the work of Pasteur, he wrote to him asking for a position in his laboratories; in a short time he became one of the principal collaborators with the master, especially in works concerning bacteriology . These were an inspiration to him, and led him to his famous theory of phagocytosis, the defensive act whereby white blood cells protect an organism against pathogenic microbes . Metchnikoff supposed that old age was avoidable, and subscribed to the materialistic school of thought . He was awarded the Nobel Prize in 1908 . (With the complements of the Jose Lopez Luis Cigarillo Factory, Tenerife).

Expert Rev Mol Diagn, 2003 Mar, 3(2), 153 - 61
Nanodiagnostics: application of nanotechnology in molecular diagnostics; Jain KK; Nanotechnology extends the limits of molecular diagnostics to the nanoscale . Nanotechnology-on-a-chip is one more dimension of microfluidic/lab-on-a-chip technology . Biological tests measuring the presence or activity of selected substances become quicker, more sensitive and more flexible when certain nanoscale particles are put to work as tags or labels . Magnetic nanoparticles, bound to a suitable antibody, are used to label specific molecules, structures or microorganisms . Magnetic immunoassay techniques have been developed in which the magnetic field generated by the magnetically labeled targets is detected directly with a sensitive magnetometer . Gold nanoparticles tagged with short segments of DNA can be used for detection of genetic sequence in a sample . Multicolor optical coding for biological assays has been achieved by embedding different-sized quantum dots into polymeric microbeads . Nanopore technology for analysis of nucleic acids converts strings of nucleotides directly into electronic signatures . DNA nanomachines can function as biomolecular detectors for homogeneous assays . Nanobarcodes, submicrometer metallic barcodes with striping patterns prepared by sequential electrochemical depositon of metal, show differential reflectivity of adjacent stripes enabling identification of the striping patterns by conventional light microscopy . All this has applications in population diagnostics and in point-of-care hand-held devices.

Plant Physiol, 2003 Mar, 131(3), 941 - 51
A cluster of genes encodes the two types of chalcone isomerase involved in the biosynthesis of general flavonoids and legume-specific 5-deoxy(iso)flavonoids in Lotus japonicus; Shimada N et al.; Leguminous plants produce 5-deoxyflavonoids and 5-deoxyisoflavonoids that play essential roles in legume-microbe interactions . Together with chalcone polyketide reductase and cytochrome P450 2-hydroxyisoflavanone synthase, the chalcone isomerase (CHI) of leguminous plants is fundamental in the construction of these ecophysiologically active flavonoids . Although CHIs of nonleguminous plants isomerize only 6'-hydroxychalcone to 5-hydroxyflavanone (CHIs with this function are referred to as type I), leguminous CHIs convert both 6'-deoxychalcone and 6'-hydroxychalcone to 5-deoxyflavanone and 5-hydroxyflavanone, respectively (referred to as type II) . In this study, we isolated multiple CHI cDNAs (cCHI1-cCHI3) from a model legume, Lotus japonicus . In contrast to previous observations, the amino acid sequence of CHI2 was highly homologous to nonleguminous CHIs, whereas CHI1 and CHI3 were the conventional leguminous type . Furthermore, genome sequence analysis revealed that four CHI genes (CHI1-3 and a putative gene, CHI4) form a tandem cluster within 15 kb . Biochemical analysis with recombinant CHIs expressed in Escherichia coli confirmed that CHI1 and CHI3 are type II CHIs and that CHI2 is a type I CHI . The occurrence of both types of CHIs is probably common in leguminous plants, and it was suggested that type II CHIs evolved from an ancestral CHI by gene duplication and began to produce 5-deoxy(iso)flavonoids along with the establishment of the Fabaceae.

Adv Dent Res, 2001 Aug, 15, 68 - 71
Odontoblast function seen as the response of dentinal tissue to dental caries; Larmas M; Microbes are responsible for the initiation and maintaining of carious processes . They have an efficient machinery for dissolving crystalline hydroxyapatite . When initiating carious processes, microbial acid formation determines the rate of the process in enamel . When the process reaches dentin, the micro-environment changes . Dential fluid in dentin tubules is the liquid where dissolving products of apatites are destroyed . Inorganic composition of dentinal fluid, however, is not altered much during the carious process, indicating that a functional secretory domain is working to pump the dissolved calcium and phosphate ions out of the fluid . Activation of odontoblast alkaline phosphatase and dentin latent collagenases is the known cellular event during the carious process in dentin . Because the caries lesion is by definition undermining, this suggests that, in this degradation process, the extracellular compartment, crystalline hydroxyapatite is dissolved by microbial acids, and a mixture of proteinases degrades the organic matrix . The degradation products of collagen and other matrix components in dentinal fluid must be transported either through the caries lesion in the enamel to saliva or through the odontoblast to the pulp (active transport) . This facilitates further processing of the degradation products intracellularly during the passage through the cell.

Arch Microbiol, 2003 May, 179(5), 339 - 53 Epub 2003 Mar 15.
Exploring the Penicillium marneffei genome; Yuen KY et al.; Penicillium marneffei is a dimorphic fungus that intracellularly infects the reticuloendothelial system of humans and bamboo rats . Endemic in Southeast Asia, it infects 10% of AIDS patients in this region . The absence of a sexual stage and the highly infectious nature of the mould-phase conidia have impaired studies on thermal dimorphic switching and host-microbe interactions . Genomic analysis, therefore, could provide crucial information . Pulsed-field gel electrophoresis of genomic DNA of P . marneffei revealed three or more chromosomes (5.0, 4.0, and 2.2 Mb) . Telomeric fingerprinting revealed 6-12 bands, suggesting that there were chromosomes of similar sizes . The genome size of P . marneffei was hence about 17.8-26.2 Mb . G+C content of the genome is 48.8 mol% . Random exploration of the genome of P . marneffei yielded 2303 random sequence tags (RSTs), corresponding to 9% of the genome, with 11.7, 6.3, and 17.4% of the RSTs having sequence similarity to yeast-specific sequences, non-yeast fungus sequences, and both (common sequences), respectively . Analysis of the RSTs revealed genes for information transfer (ribosomal protein genes, tRNA synthetase subunits, translation initiation, and elongation factors), metabolism, and compartmentalization, including several multi-drug-resistance protein genes and homologues of fluconazole-resistance gene . Furthermore, the presence of genes encoding pheromone homologues and ankyrin repeat-containing proteins of other fungi and algae strongly suggests the presence of a sexual stage that presumably exists in the environment.

J Gravit Physiol, 2001 Jul, 8(1), P43 - 4
Nucleolar structure and function under clinorotation; Sobol MA; A nucleolus is the dynamic part of a cell nucleus where rDNA transcription, rRNA precursor processing and transport are proceeding . Investigations of the influence of microgravity and clinorotation on the structure and function of nucleolus began more than thirty years ago but, unfortunately, now there are only some articles concerning the nucleolar peculiarities in altered gravity . Available data about alterations of nucleolar morphology and function under the influence of high and low temperature, hypoxia and UV-microbeam irradiation allow us to put intent attention to the study of the nucleolus reactions on clinorotation . Therefore, the aim of our work was to investigate the ultrastructural organization and functional activity of nucleoli in Lepidium sativum root meristematic cells under clinorotation in order to understand whether a nucleolus can react to gravity.

Environ Sci Technol, 2003 Feb 15, 37(4), 786 - 91
Application of high-angle annular dark field scanning transmission electron microscopy, scanning transmission electron microscopy-energy dispersive X-ray spectrometry, and energy-filtered transmission electron microscopy to the characterization of nanoparticles in the environment; Utsunomiya S et al.; A major challenge to the development of a fundamental understanding of transport and retardation mechanisms of trace metal contaminants (<10 ppm) is their identification and characterization at the nanoscale . Atomic-scale techniques, such as conventional transmission electron microscopy, although powerful, are limited by the extremely small amounts of material that are examined . However, recent advances in electron microscopy provide a number of new analytical techniques that expand its application in environmental studies, particularly those concerning heavy metals on airborne particulates or water-borne colloids . High-angle annular dark field scanning transmission electron microscopy (HAADF-STEM), STEM-energy-dispersive X-ray spectrometry (EDX), and energy-filtered TEM (EFTEM) can be effectively used to identify and characterize nanoparticles . The image contrast in HAADF-STEM is strongly correlated to the atomic mass: heavier elements contribute to brighter contrast . Gold nanocrystals in pyrite and uranium nanocrystals in atmospheric aerosols have been identified by HAADF-STEM and STEM-EDX mapping and subsequently characterized by high-resolution TEM (HRTEM) . EFTEM was used to identify U and Fe nanocrystals embedded in an aluminosilicate . A rare, As-bearing nanophase, westerveldite (FeAs), was identified by STEM-EDX and HRTEM . The combined use of these techniques greatly expands the effective application of electron microscopy in environmental studies, especially when applied to metals of very low concentrations . This paper describes examples of how these electron microbeam techniques can be used in combination to characterize a low concentration of heavy metals (a few ppm) on nanoscale particles.

J Androl, 2003 Mar-Apr, 24(2), 246 - 52
Deterioration of plasma membrane is associated with activated caspases in human spermatozoa; Paasch U et al.; Spermatozoa with deteriorated plasma membranes can be separated by magnetic-activated cell sorting (MACS) after binding superparamagnetic annexin V-conjugated microbeads (ANMBs) to membrane phosphatidylserine (PS) . Semen samples from 15 donors and 25 infertile patients were divided into 2 spermatozoal fractions by annexin V-MACS . Activated caspases (aCPs), which mediate degradations of cell quality, were determined by CaspaTag in the 2 subpopulations . Spermatozoa from donors showed lower levels of bound annexin V (3.6% +/- 0.5% vs 11.9% +/- 1.1%; P <.01) and aCPs (21.8% +/- 2.6% vs 43.2% +/- 2.1%; P <.01) than did spermatozoa from infertile patients . MACS resulted in a decrease of spermatozoa with aCPs from 21.8% +/- 2.6% (before separation) to 9.2% +/- 1.4% (in the ANMB-negative fraction) in donors and from 43.2% +/- 2.1% to 18.8% +/- 2.6% in infertile patients (mean +/- SEM; P <.01) . Separation effects of the MACS technique were confirmed with flow cytometry using anti-annexin V antibodies and with electron microscopy . ANMB-MACS removes spermatozoa with PS-bound annexin V and produces a higher quality spermatozoal fraction . Spermatozoa with a deteriorated membrane are characterized by an increase in aCPs . A higher percentage of spermatozoa with ANMBs bound to PS and with aCPs were found in infertile patients.

World J Gastroenterol, 2003 Mar, 9(3), 479 - 84
Antitumor immunopreventive and immunotherapeutic effect in mice induced by hybrid vaccine of dendritic cells and hepatocarcinoma in vivo; Zhang JK et al.; AIM: To develop atumor vaccine by fusion of H22 hepatocarcinoma cells and DC, and to study its protective and therapeutical effect against H22 cell . METHODS: H22-DC vaccine was produced by PEG fusion of H22 and DC induced by cytokine released from splenic mononuclear cells, sorted by CD11c magnetic microbead marker . It was injected through the tail vein of the mice and the H(22)-DC oncogenesis was detected in the liver, spleen and lung . In order to study the therapeutical and protective effect of H(22)-DC against tumor H(22), two groups were divided: immune group and therapeutic group . Immune group was further divided into P, D, HD and H subgroups, immunized by PBS, DC, H(22)-DC and inactivated H(22), respectively, and attacked by H(22) cell . The tumor size, tumor weight, mice survival time and tumor latent period were recorded and statistically analyzed; Therapeutical group was divided into three subgroups of P, D and HD, and attacked by H(22), then treated with PBS, DC, and H(22)-DC, respectively . Pathology and flow cytometry were also applied to study the mechanism how the H(22)-DC vaccine attacked on the H(22) cell . RESULTS: 1 . No oncogenesis was found in spleen, lung and liver after H22-DC injection . 2 . Hybrid vaccine immunized mice had strongest CTL activity . 3 . In the immune group, latent period was longer in HD subgroup than that in P, H and D subgroup; and tumor size and weight were smaller in HD subgroup than that in P, H and D subgroup . 4 . In therapeutic group, tumor size was smaller in HD subgroup than that in P, D subgroup . CONCLUSION: 1 . H22-DC tumor vaccine is safe without oncogenesis in vivo . 2 . Hybrid vaccine can stimulate potent specific CTL activity against H22 . 3 . H22-DC vaccine has distinctive prophylatic effect on tumor H22 and can inhibit the tumor growth.

Eur Biophys J, 2003 Mar, 32(1), 33 - 9 Epub 2003 Jan 28.
Combined nanomanipulation by atomic force microscopy and UV-laser ablation for chromosomal dissection; Stark RW et al.; Nanomanipulation and nanoextraction on a scale close to and beyond the resolution limit of light microscopy is needed for many modern applications in biological research . For the manipulation of biological specimens a combined microscope allowing for ultraviolet (UV) microbeam laser manipulation together with manipulation by an atomic force microscope (AFM) was used . In a one-step procedure, human metaphase chromosomes were dissected optically by the UV-laser ablation and mechanically by AFM manipulation . With both methods, sub-400-nm cuts could be achieved routinely . Thus, the AFM is an indispensable tool for in situ quality control of nanomanipulation . However, already on this scale the dilation of the topographic AFM image due to the tip geometry can become significant . Therefore the AFM images were restored using a tip geometry obtained by a blind tip-reconstruction algorithm . Cross-sectional analysis of the restored image reveals a 380-nm-wide UV-laser cut and AFM cuts between 70 nm and 280 nm.

Environ Sci Technol, 2003 Feb 1, 37(3), 616 - 23
Interpreting deposition patterns of microbial particles in laboratory-scale column experiments; Tufenkji N et al.; The transport and fate of microbial particles in subsurface environments is controlled by their capture (natural filtration) by sediment grains . Typically, filtration models used to describe microbe removal in porous media predict exponential decrease in microbial particle concentration with travel distance . However, a growing body of laboratory-scale column experiments suggests that the retained microbial particle profiles decay nonexponentially . The observed behavior may be attributed to the heterogeneity in the interactions between microbial particles and sediment grains, most likely due to the inherent variability in the microbial particles . This factor can be incorporated into classical colloid filtration (deposition) theory by inclusion of a distribution in the deposition rate coefficient . We show that certain distributions of the deposition rate coefficient (i.e., log-normal, bimodal, and power-law distributions) give rise to nonexponential deposition patterns . Comparisons of model predictions to experimental data indicate that the observed nonexponential deposition behavior of bacteria and virus particles may be attributed to a broad range (i.e., a power-law distribution) of microbial deposition rates . Other mechanisms such as particle release and blocking by previously deposited microbial particles are also shown to be potential sources of deviation from the classical filtration theory . Our results further suggest that monitoring fluid-phase particle concentration is insufficient for accurate characterization of the deposition and transport behavior of microbial particles in saturated porous media . Rather, the shape of the microbial particle retention profile is shown to be a key indicator of the mechanisms controlling microbial deposition and transport.

Crit Care Med, 2003 Mar, 31(3), 787 - 92
Free radical and drug oxidation products in an intensive care unit sedative: propofol with sulfite; Baker MT et al.; OBJECTIVES: Some propofol emulsion formulations contain EDTA or sodium metabisulfite to inhibit microbe growth on extrinsic contamination . EDTA is not known to react with propofol formulation components; however, sulfite has been shown to support some oxidation processes and may react with propofol . This study compared the oxidation of propofol and the formation of free radicals by electron paramagnetic resonance analysis in EDTA and sulfite propofol emulsions during a simulated intensive care unit 12-hr intravenous infusion . DESIGN: Controlled laboratory study . SETTING: University laboratory . MEASUREMENTS AND MAIN RESULTS: Propofol emulsions (3.5 mL) were dripped from spiked 50-mL vials at each hour for 12 hrs . Two propofol oxidation products, identified as propofol dimer and propofol dimer quinone, were detected in sulfite and EDTA propofol emulsions; however, sulfite propofol emulsion contained higher quantities of both compounds . After initiation of the simulated infusion, the quantities of propofol dimer and propofol dimer quinone increased in the sulfite propofol emulsion, but the lower levels in the EDTA propofol emulsion remained constant . Sulfite propofol emulsion began to visibly yellow at about 6-7 hrs . The EDTA propofol emulsion remained white at all times . The absorbance spectra of the propofol dimer and propofol dimer quinone extracted from sulfite propofol emulsion showed that propofol dimer did not absorb in the visible spectrum, but the propofol dimer quinone had an absorbance peak at 421 nm, causing it to appear yellow . Electron paramagnetic resonance analysis of the propofol emulsion containing metabisulfite revealed that the sulfite propofol emulsion yielded a strong free radical signal consistent with the formation of the sulfite anion radical (SO3*-) . The EDTA propofol emulsion yielded no free radical signal above background . CONCLUSION: Sulfite from the metabisulfite additive in propofol emulsion creates an oxidative environment when these emulsions are exposed to air during a simulated intravenous infusion . This oxidation results in propofol dimerization and emulsion yellowing, the latter of which is caused by the formation of propofol dimer quinone . These processes can be attributed to the rapid formation of the reactive sulfite free radical.

Amino Acids, 2003, 24(1-2), 73 - 80
Degradation of tryptophan and related indolic compounds by ruminal bacteria, protozoa and their mixture in vitro; Mohammed N et al.; In vitro experiments were conducted to examine the degradation of d- and l-isomers of tryptophan (Trp) and 10 related indolic compounds by mixed rumen bacteria (B), protozoa (P) and a combination of the two (BP) . The analyses were carried out by HPLC . d-Trp (1.0 mM) was not degraded by rumen microorganisms during the 24-h incubation period . The net degradation of 1 mM l-Trp was 46.5%, 8.7% and 80.0% by B, P and BP suspensions, respectively . Trp was degraded into indoleacetic acid, indolelactic acid and indole by rumen bacteria and protozoa, and into skatole, p-cresol and indolepropionic acid by rumen bacteria only . Of them, indoleacetic acid was the major product of Trp found in B (15.4%) and P (3.1%), and skatole in BP (43.2%) . This is the first report of the production of indolelactic acid and p-cresol from Trp by rumen microbes . Starch, d-glucose, salinomycin and monensin inhibited the production of skatole and indole from Trp, and skatole from indoleacetic acid by rumen bacteria.

Indian J Exp Biol, 2002 Feb, 40(2), 187 - 91
Inhibition of endocytotic functions in Dictyostelium discoideum treated with a carbamate pesticide; Gurumurthy Y et al.; Administration of a carbamate pesticide carbaryl (1-Naphthyl-N-methyl carbamate) at a concentration of 60 and 100 ppm greatly inhibits the endocytotic functions during growth of the cellular slime mold D . discoideum . The ingestion of fluorescien isothiocynate (FITC) labeled E . coli is reduced between 30 and 40% in the treated cells as compared to controls . Similarly, the uptake of FITC-labeled dextran, which has been used as fluid-phase marker for pinocytosis also show 40-50% inhibition in the treated cells . 3H-leucine uptake and incorporation are also inhibited in the treated cells . SDS-PAGE analysis of cytoskeletal proteins shows a higher actin association with the membrane of treated cells . The results demonstrate the detrimental effects of Carbamate on the soil microbe even at a very low concentration and the efficacy of the slime mold cells as a biosensor for the carbamate-induced cytotoxicity.

Phytochemistry, 2003 Feb, 62(3), 377 - 87
Occurrence and non-detectability of maytansinoids in individual plants of the genera Maytenus and Putterlickia; Pullen CB et al.; Individual plants belonging to different species of the family Celastraceae collected from their natural habitats in South Africa (Putterlickia verrucosa (E . Meyer ex Sonder) Szyszyl., Putterlickia pyracantha (L.) Szyszyl., Putterlickia retrospinosa van Wyk and Mostert) and Brazil (Maytenus ilicifolia Mart . ex Reiss., Maytenus evonymoides Reiss., Maytenus aquifolia Mart.) were investigated for the presence of maytansinoids and of maytansine, an ansamycin of high cytotoxic activity . Maytansinoids were not detectable in plants grown in Brazil . Analysis of plants growing in South Africa, however, showed clearly that maytansinoids were present in some individual plants but were not detectable in others . Molecular biological analysis of a Putterlickia verrucosa cell culture gave no evidence for the presence of the aminohydroxybenzoate synthase gene which is unique to the biosynthesis of aminohydroxybenzoate, a precursor of the ansamycins including maytansinoids . Moreover, this gene was not detectable in DNA extracted from the aerial parts of Putterlickia plants . In contrast, observations indicate that this gene may be present in microbes of the rhizosphere of Putterlickia plants . Our observations are discussed with respect to the possibility that the roots of Putterlickia plants may be associated with microorganisms which are responsible for the biosynthesis of maytansine or maytansinoids.

Eksp Klin Gastroenterol, 2002, (5), 92 - 6, 129-30
{Antibiotic-associated diarrhea}; Parfenov AI et al.; There are more than 500 species of microbes in the human bowels, and their total amount reaches 10(14), which is much higher than the total quantity of the cellular content in human organism . The history of teaching about microbiocenosis demonstrates various connections of microorganisms with the bowels and other organs and systems of human body . The available data about the significance of the bowels microbe flora for human organism give grounds for comparing it with the nervous, cardiovascular or any other organism system.

Br J Cancer, 2003 Mar 10, 88(5), 767 - 74
A proliferation-dependent bystander effect in primary porcine and human urothelial explants in response to targeted irradiation; Belyakov OV et al.; The aim of this study was to test whether radiation-induced bystander effects are involved in the response of multicellular systems to targeted irradiation . A primary explant technique was used that reconstructed the in vivo microarchitecture of normal urothelium with proliferating and differentiated cells present . Sections of human and porcine ureter were cultured as explants and irradiated on day 7 when the urothelial outgrowth formed a halo around the tissue fragment . The Gray Cancer Institute charge particle microbeam facility allowed the irradiation of individual cells within the explant outgrowth with a predetermined exact number of (3)He(2+) ions (which have very similar biological effectiveness to alpha-particles) . A total of 10 individual cell nuclei were irradiated with 10 (3)He(2+) ions either on the periphery, where proliferating cells are located, or at the centre of the explant outgrowth, which consisted of terminally differentiated cells . Samples were fixed 3 days after irradiation, stained and scored . The fraction of apoptotic and micronucleated cells was measured and a significant bystander-induced damage was observed . Approximately 2000-6000 cells could be damaged by the irradiation of a few cells initially, suggesting a cascade mechanism of cell damage induction . However, the fraction of micronucleated and apoptotic cells did not exceed 1-2% of the total number of the cells within the explant outgrowth . It is concluded that the bystander-induced damage depends on the proliferation status of the cells and can be observed in an in vitro explant model.

Am J Physiol Lung Cell Mol Physiol, 2003 Apr, 284(4), L566 - 77
Pathophysiological roles of interleukin-8/CXCL8 in pulmonary diseases; Mukaida N; Fifteen years have passed since the first description of interleukin (IL)-8/CXCL8 as a potent neutrophil chemotactic factor . Accumulating evidence has demonstrated that various types of cells can produce a large amount of IL-8/CXCL8 in response to a wide variety of stimuli, including proinflammatory cytokines, microbes and their products, and environmental changes such as hypoxia, reperfusion, and hyperoxia . Numerous observations have established IL-8/CXCL8 as a key mediator in neutrophil-mediated acute inflammation due to its potent actions on neutrophils . However, several lines of evidence indicate that IL-8/CXCL8 has a wide range of actions on various types of cells, including lymphocytes, monocytes, endothelial cells, and fibroblasts, besides neutrophils . The discovery of these biological functions suggests that IL-8/CXCL8 has crucial roles in various pathological conditions such as chronic inflammation and cancer . Here, an overview of its protein structure, mechanisms of production, and receptor system will be discussed as well as the pathophysiological roles of IL-8/CXCL8 in various types of lung pathologies.

J Control Release, 2003 Feb 21, 87(1-3), 139 - 51
Targeting caveolae for vesicular drug transport; Gumbleton M et al.; Caveolae are morphologically evident as omega-shaped invaginations of the plasma membrane with a diameter of 50-100 nm . They may also exist in a variety of other forms including flattened domains indistinguishable from the plasma membrane itself . At least in some cell types caveolae undertake transport functions including that of the endocytic and transcytotic movement of macromolecules, and indeed microbes and microbial toxins . Opportunities exist for basic and applied investigators working within the pharmaceutical sciences to exploit caveolae membrane interactions with the aim to develop of novel cellular or transcellular drug delivery strategies . This overview article will provide: pertinent information on the biology of the caveolae membrane system; review the various caveolae isolation methods; highlight some of the literature evidence showing that caveolae are functional with regard to macromolecule transport; discuss the role that caveolae could fulfill in the pulmonary absorption of therapeutic proteins from alveolar airspace to capillary blood following inhalational drug delivery, and finally review some very recent work showing proof-of-principle that caveolae domains can be targeted in a tissue-specific manner with highly selective ligands .

J Agric Food Chem, 2003 Mar 12, 51(6), 1710 - 7
Purification and identification of barley (Hordeum vulgare L.) proteins that inhibit the alkaline serine proteinases of Fusarium culmorum; Pekkarinen AI et al.; It has been proposed that microbial proteinase inhibitors, which are present in abundance in cereal grains, protect the seed against plant pathogens . So far, however, very little is known about the interactions of those inhibitors with the proteinases of phytopathogenic microbes . The increased alkaline proteinase activities of Fusarium head blight (FHB) diseased wheat and barley grain imply that the Fusarium fungi synthesize those enzymes during the colonization of the kernel . To study which barley proteins can inhibit Fusarium proteinases, and hence, possibly protect the seed from FHB, the proteins of a grain extract have been separated and tested for their abilities to inhibit two alkaline serine proteinases that we previously isolated from F . culmorum . The proteins were separated by size exclusion, ion exchange, and reversed-phase-HPLC chromatographies . The purified inhibitors were identified by their molecular masses and N-terminal amino acid sequences . The proteins that inhibited the subtilisin-like Fusarium proteinase were the chymotrypsin/subtilisin (CI) inhibitors 1A, 1B, and 2A and the barley alpha-amylase/subtilisin inhibitor (BASI) . Only one of the purified proteins inhibited the trypsin-like proteinase, the barley Bowman-Birk inhibitor (BBBI) . No novel inhibitors were detected.

Med Hypotheses, 2003 Apr, 60(4), 567 - 72
The physiology and pharmacology of singlet oxygen; Stief TW; Reactive oxygen species (ROS) are generated by many different cells . Singlet oxygen (1O(2)) and a reaction product of it, excited carbonyls (C=O*), are important ROS . 1O(2) and C=O* are nonradicalic and emit light (one photon/molecule) when returning to ground state oxygen . Especially activated polymorphonuclear neutrophil granulocytes (PMN) produce large amounts of 1O(2) . Via activation of the respiratory burst (NADPH oxidase and myeloperoxidase) they synthesize hypochlorite (NaOCl) and chloramines (in particular N-chlorotaurine) . Chloramines are selective and stable chemical generators of 1O(2) . In the human organism, 1O(2) is both a signal and a weapon with therapeutic potency against very different pathogens, such as microbes, virus, cancer cells and thrombi . Chloramines at blood concentrations between 1 and 2 mmol/L inactivate lipid enveloped virus and chloramines at blood concentrations below 0.5 mmol/L, i.e . at oxidant concentrations that do not affect thrombocytes or hemostasis factors, act antithrombotically by activation of the physiologic PMN mediated fibrinolysis; this thrombolysis is of selective nature, i.e . it does not impair the hemostasis system of the patient allowing the antithrombotic treatment in patients where the current risky thrombolytic treatment is contraindicated . The action of 1O(2) might be compared to the signaling and destroying gunfire of soldiers directed against bandits at night, resulting in an autorecruitment of the physiological inflammatory response . Chloramines (such as the mild and untoxic oxidant chloramine T (N-chloro-p-toluene-sulfonamide)) and their signaling and destroying reaction product 1O(2) might be promising new therapeutic agents against a multitude of up to now refractory diseases .

Brain Behav Immun, 2003 Feb, 17(1), 13 - 9
Molecular insights on the cerebral innate immune system; Rivest S; All species need an immediate reply to the microbial pathogens that is part of an effective immune response and is essential for the survival of most organisms . This reply is known as the innate immune response and is characterized by the de novo production of mediators that either kill the microbes directly or activate phagocytic cells to ingest and kill them . The innate immune response can be driven through specific recognition systems, the best example being an interaction between the endotoxin lipopolysaccharide (LPS) and its receptors CD14 and Toll-like receptor 4 (TLR4) . For a long time, the brain was considered to be a privileged organ from an immunological point of view, owing to its inability to mount an immune response and process antigens . Although this is partly true, the CNS shows a well-organized innate immune reaction in response to systemic bacterial infection and cerebral injury . The CD14 and TLR4 receptors are constitutively expressed in the circumventricular organs (CVOs), choroid plexus and leptomeninges . Circulating LPS is able to cause a rapid transcriptional activation of genes encoding CD14 and TLR2, as well as a wide variety of pro-inflammatory molecules in CVOs . A delayed response to LPS takes place in cells located at boundaries of the CVOs and in microglia across the CNS . Therefore, without having direct access to the brain parenchyma, pathogens have the ability to trigger an innate immune reaction throughout cerebral tissue . This review presents evidence supporting the existence of such a system in the brain, which is finely regulated at the transcription level . Transient activation of this system is not harmful toward neuronal elements.

Nat Rev Genet, 2003 Mar, 4(3), 195 - 205
Mice, microbes and models of infection; Buer J et al.; We urgently need animal models to study infectious disease . Mice are susceptible to a similar range of microbial infections as humans . Marked differences between inbred strains of mice in their response to pathogen infection can be exploited to analyse the genetic basis of infections . In addition, the genetic tools that are available in the laboratory mouse, and new techniques to monitor the expression of bacterial genes in vivo, make it the principal experimental animal model for studying mechanisms of infection and immunity.

Indoor Air, 2003 Mar, 13(1), 65 - 73
The relation between growth of four microbes on six different plasterboards and biological activity of spores; Murtoniemi T et al.; Microbial growth on water-damaged building materials is commonly associated with adverse health effects in the occupants . We examined the growth of Stachybotrys chartarum, Aspergillus versicolor, Penicillium spinulosum, and Streptomyces californicus, isolated from water-damaged buildings, on six different brands of plasterboards . The microbial growth was compared with the biological activity of the spores, that is the potential to induce cytotoxicity and proinflammatory mediators in RAW264.7 macrophages . These results showed that the microbial growth on plasterboard depended on both the microbial strain and the brand of plasterboard used . The biological activity of spores appeared to be regulated by different growth conditions on plasterboards so that good microbial growth was associated with a low bioactivity of the spores, whereas the spores collected from plasterboard supporting only weak growth usually were biologically active . Cytotoxicity of either S . chartarum or A . versicolor did not correlate with any particular growth conditions or induced inflammatory responses . Instead, there were positive correlations between cytotoxicity and levels of induced proinflammatory cytokines for P . spinulosum and S . californicus . These data suggest that both the microbial growth on plasterboard and the resulting bioactivity of spores vary and might be affected by changing the growth conditions provided by the plasterboards.

Anal Sci, 2003 Feb, 19(2), 289 - 94
Determination of thiamine in pharmaceutical preparations by sequential injection renewable surface solid-phase spectrofluorometry; Zhu H et al.; Fluorometric determination of thiamine requires the conversion of the analyte to fluorescent thiochrome by hexacyanoferrate(III) oxidation in alkaline solution and the isolation of the produced thiochrome from the reaction medium by solvent extraction . It was observed that thiochrome could be concentrated and separated from the reaction medium by solid-phase extraction . The thiochrome sorpted on the surface of octadecyl-alklylated poly{styrene/divinylbenzene} (C18-PS/DP) microbeads emitted strong fluorescence upon excitation, the maximum excitation and emission wavelengths being 385 nm and 433 nm, respectively . Based on this observation, a sequential injection renewable surface solid-phase spectrofluorometry was developed for the determination of thiamine . A sequential injection system on-line coupled to a chip-based flow-through cell was employed to handle the chemical reaction, bead injection and discharging, and adsorption of thiochrome . Solid-phase fluorometric detection was realized by coupling the chip-based flow-through cell to a spectrofluorometer with a multistrand bifurcated optical fiber . Under the optimized condition, a detection limit of 0.03 microg ml(-1) was achieved at the sample throughput of 30 h(-1) and consumption of 1 mg C18-PS/DP microbeads for each run . Eleven runs of a 2 microg ml(-1) thiamine standard solution gave a relative standard deviation of 1.0% . The developed approach was successfully applied for the determination of thiamine contents in pharmaceutical preparations.

J Synchrotron Radiat, 2003 Mar 1, 10(Pt 2), 187 - 90 Epub 2003 Feb 27.
Miniature ionization chamber detector developed for X-ray microprobe measurements; Kocsis M et al.; A windowless small ionization chamber detector has been developed for monitoring the intensity of the microbeam at the ID18F microprobe end-station of the European Synchrotron Radiation Facility . The small dimensions of the ionization chamber (10 mm along the beam direction and 5 mm perpendicular to it) make it possible to place it very close to the sample . A pinhole of diameter 50 microm was used for defining the entrance window of the ionization chamber; thus the small counter can be used as an order-selecting aperture while measuring simultaneously the intensity after the aperture . In the present work the technical characteristics, such as the current-voltage curve, stability and linearity, of the small monitor have been tested.

Can J Gastroenterol, 2003 Feb, 17(2), 107 - 9
The establishment of a national tissue bank for inflammatory bowel disease research in Canada; Collins SM et al.; The Crohn's and Colitis Foundation of Canada (CCFC) has established a national bank for tissue, serum and blood from patients with inflammatory bowel disease (IBD) . Investigators from across the country submit material to the bank together with clinical data . Investigators may access their own patient information from the bank for their own study purposes, but the distribution of tissue is restricted to specific CCFC-funded projects . Currently, tissues are being collected from newly diagnosed, untreated IBD patients to support a recent initiative aimed at characterizing microbes in colonic and ileal biopsies from such patients . In the future, criteria for the submission of tissue will be tailored to specific research questions . This bank is believed to be the first national bank of its kind dedicated to research in Crohn's disease and ulcerative colitis

J Invest Dermatol, 2003 Mar, 120(3), 372 - 8
Memory B cells specific for the NC16A domain of the 180 kDa bullous pemphigoid autoantigen can be detected in peripheral blood of bullous pemphigoid patients and induced in vitro to synthesize autoantibodies; Leyendeckers H et al.; Bullous pemphigoid is a subepidermal blistering disease characterized by the synthesis of autoantibodies against the 180 kDa and the 230 kDa bullous pemphigoid antigens . Whether autoimmunity is also reflected by the presence of circulating autoantigen-specific memory B cells is still a matter of debate . We used a new assay combining two-step immunomagnetic enrichment with multiparameter flow cytometry to detect and characterize bullous pemphigoid 180 kDa-specific IgG+ B cells in blood of bullous pemphigoid patients . In a first magnetic separation, B cells were isolated from peripheral blood mononuclear cells using releasable microbeads conjugated to a CD19 antibody . From pre-enriched B cells, bullous pemphigoid 180 kDa-specific cells were then positively selected using microbeads directly conjugated with a recombinant N-terminal fragment of the bullous pemphigoid 180 kDa ectodomain, containing the noncollagenous 16A domain, which was recently shown to harbor major epitopes of autoantibodies in bullous pemphigoid sera . Noncollagenous 16A domain-specific IgG+ B cells were detectable in blood of most, if not all patients with serum autoantibodies against the noncollagenous 16A domain . The specificity of the cells was confirmed by in vitro differentiation into antibody-forming cells and analysis of the culture supernatant for the presence of noncollagenous 16A domain-specific IgG antibodies . All noncollagenous 16A domain-specific IgG+ B cells showed a clear memory immunophenotype . Noncollagenous 16A domain-specific IgG+ memory B cells may be crucial for continuous noncollagenous 16A domain-specific autoantibody production and/or play a part as antigen-presenting cells for priming and restimulation of bullous pemphigoid 180 kDa-specific T helper cells.

Infect Control Hosp Epidemiol, 2003 Feb, 24(2), 139 - 41
Microbial aerosol contamination of dental healthcare workers' faces and other surfaces in dental practice; Prospero E et al.; The purpose of this study was to focus attention on the need to adopt infection control procedures in dentistry . The quantitative and qualitative bacterial contamination of dental healthcare workers' faces and other surfaces in dental practice was determined . Oral fluids become aerosolized during dentistry and oral microbes have been used as the markers of their spread that may carry blood-borne pathogens.

Microsc Microanal, 2001 Mar, 7(2), 150 - 158
Wavelength Dispersive Spectrometer and Energy Dispersive Spectrometer Automation: Past and Future Development; McCarthy JJ et al.; As part of the Microbeam Analysis Society (MAS) symposium marking 50 years of electron microprobe analysis, this article reviews the important advances made over the decades to the automation of data collection and computerized analysis of data from the electron microprobe . Out of many innovations that contributed to the advance of microprobe automation, we have chosen to focus on a few developments that the authors feel represent the major trends in advancement of the "state of the art" of this instrumentation . After providing brief summaries of the three generations of advances in the hardware and software of automation systems, several key applications developments are described, followed by our prediction of which current developments may impact the future automation of the microprobe.

Biochim Biophys Acta, 2003 Mar 17, 1620(1-3), 218 - 24
Lead-revealed lipid organization in human hair; Bertrand L et al.; Human hair lipids form a complex mixture of composition close to that of sebum . Part of these lipids appears in an organized state that has been studied by diffraction techniques in the literature . Nevertheless, information on the structure of these lipids remains very scarce due to their low contribution to global hair diffraction pattern . Here we show that appropriate lead treatment considerably enhances organized lipid features observed by microbeam synchrotron radiation diffraction experiments . We attribute these features to the formation of lead soaps of free fatty acids . Specific orientation of hair "lipid crystals" in planes parallel to the hair axis is clearly demonstrated . Inclusion of these lipids in the bulk of the hair shaft is shown by diffraction experiments following removal of the cuticular outermost layer of hair . Moreover, microfluorescence and diffraction experiments are consistent with part of the lipids being present as calcium soaps in native hair . We therefore consider lead fixation as a powerful tool to evaluate the lipid organization in human hair for medical, environmental and archaeological purposes, including lead poisoning.

Surg Infect (Larchmt), 2001 Summer, 2(2), 103 - 10; discussion 110-2
Hazardous crossing: immunosuppression and nosocomial infections in solid organ transplant recipients; Dunn DL; BACKGROUND: During the past decade, ever-increasing numbers of patients have undergone renal, pancreatic, small bowel, hepatic, cardiac, or lung transplantation as therapy for various types of renal disease requiring dialytic therapy . Indications for solid organ transplantation include type I and, rarely, type II diabetes mellitus; hyperalimentation-dependent short gut syndrome; and formerly fatal liver, cardiac, or pulmonary failure . Significant improvements in patient and allograft survival have been observed in all categories . Unfortunately, despite such improved results, the risks of infection related to immunosuppression continue to be substantial . METHODS: Review of pertinent studies from the English literature . RESULTS: Suppression of host defenses by exogenous immunosuppressive agents renders patients susceptible to invasion by either resident or environmental bacterial, fungal, viral, and protozoal microbes or parasites . In such patients, invasion of organisms that produce mild infection in nonimmunosuppressed individuals can produce severe, lethal disease . Moreover, even low-virulence microbes may invade, proliferate, and cause disease in the immunosuppressed host; such organisms are referred to as "opportunistic" pathogens when they cause disease under these conditions . CONCLUSION: Advances in the field of transplantation have been substantial, particularly in the regulation of therapeutic immunosuppression, in prophylactic measures to prevent infection, and in more effective diagnosis and treatment modalities.

Nat Med, 2003 Mar, 9(3), 315 - 21 Epub 2003 Feb 18.
Toll-like receptor-4 (TLR4) signaling augments chemokine-induced neutrophil migration by modulating cell surface expression of chemokine receptors; Fan J et al.; Polymorphonuclear leukocytes (PMNs) are critical effector cells of the innate immune system that protect the host by migrating to inflammatory sites and killing pathogenic microbes . We addressed the role of chemokine receptor desensitization induced by G-protein-coupled receptor kinases (GRKs) in the feedback control of PMN migration . We show that the chemokine macrophage inflammatory protein-2 (MIP-2) induces GRK2 and GRK5 expression in PMNs through phosphoinositide-3-kinase (PI3K)-gamma signaling . We also show that lipopolysaccharide (LPS)-activated signaling through the Toll-like receptor (TLR)-4 pathway transcriptionally downregulates the expression of GRK2 and GRK5 in response to MIP-2 . The reduced expression of GRKs lowers chemokine receptor desensitization and markedly augments the PMN migratory response . These data indicate that TLR4 modulation of PMN surface chemokine receptor expression subsequent to the downregulation of GRK2 and GRK5 expression is a critical determinant of PMN migration.

J Allergy Clin Immunol, 2003 Feb, 111(2 Suppl), S442 - 59
1 . Overview of the immune response; Chaplin DD; Host defense against pathogenic microbes requires dramatically different responses, depending on the character of the pathogen and on the tissue under attack . Central to the immune system's ability to mobilize a response to an invading pathogen is its ability to distinguish self from nonself . The host has evolved both innate and adaptive mechanisms to respond to and eliminate pathogenic microbes . Both of these mechanisms include self-nonself discrimination . This overview describes key mechanisms used by the immune system to respond to invading microbes and identifies settings in which disturbed immune function exacerbates tissue injury.

J Cell Biol, 2003 Feb 17, 160(4), 597 - 604
Amassin, an olfactomedin protein, mediates the massive intercellular adhesion of sea urchin coelomocytes; Hillier BJ et al.; Sea urchins have a fluid-filled body cavity, the coelom, containing four types of immunocytes called coelomocytes . Within minutes after coelomic fluid is removed from the body cavity, a massive cell-cell adhesion of coelomocytes occurs . This event is referred to as clotting . Clotting is thought to be a defense mechanism against loss of coelomic fluid if the body wall is punctured, and it may also function in the cellular encapsulation of foreign material and microbes . Here we show that this intercoelomocyte adhesion is mediated by amassin, a coelomic plasma protein with a relative molecular mass (Mr) of 75 kD . Amassin forms large disulfide-bonded aggregates that adhere coelomocytes to each other . One half of the amassin protein comprises an olfactomedin (OLF) domain . Structural predictions show that amassin and other OLF domain-containing vertebrate proteins share a common architecture . This suggests that other proteins of the OLF family may function in intercellular adhesion . These findings are the first to demonstrate a function for a protein of the OLF family.

Strahlenther Onkol, 2003 Feb, 179(2), 69 - 77
Radiation-induced bystander effects . Mechanisms, biological implications, and current investigations at the Leipzig LIPSION facility; Osterreicher J et al.; BACKGROUND: The bystander effect is a relatively new area of radiobiological research, which is aimed at studying post-radiation changes in neighboring non-hit cells or tissues . The bystander effect of ionizing irradiation is important after low-dose irradiation in the range of up to 0.2 Gy, where a higher incidence of stochastic damage was observed than was expected from a linear-quadratic model . It is also important when the irradiation of a cell population is highly non-uniform . OBJECTIVE: This review summarizes most of the important results and proposed bystander effect mechanisms as well as their impact on theory and clinical practice . The literature, in parts contradictory, is collected, the main topics are outlined, and some basic papers are described in more detail . In order to illustrate the microbeam technique, which is considered relevant for the bystander effect research, the state of the Leipzig LIPSION nanoprobe facility is described . RESULTS: The resistance of a radiation-induced bystander effect is now generally accepted . The current state of knowledge on it is summarized here . Several groups worldwide are working on understanding its different aspects and its impact on radiobiology and radiation protection . CONCLUSION: The observation of a bystander effect has posed many questions, and answering them is a challenging topic for radiobiology in the future.

Res Vet Sci, 2003 Apr, 74(2), 163 - 9
Diarrhoea in the growing pig - a comparison of clinical, morphological and microbial findings between animals from good and poor performance herds; Jacobson M et al.; Diarrhoea among growing pigs (8-13 weeks old) is a significant problem in many herds . Nine herds with poor performance and diarrhoea among growing pigs were selected on the basis of their piglet mean age at a body weight of 25 kg, compared to the overall mean age in Swedish herds . In addition, four herds with good average performance and no problems with diarrhoea were selected . Pigs were necropsied and samples for histology and microbiology were collected . Based on the necropsy findings, the pigs from the good performing herds were all judged to be healthy . The presence of Brachyspira pilosicoli and Lawsonia intracellularis was significantly correlated to poor performing herds and the results indicate that these microbes are main pathogens involved in enteric diseases among Swedish grower pigs . In addition, concomitant infections with other presumptive pathogens were commonly found.

J Intern Med, 2003 Jan, 253(1), 4 - 17
Is there a role for microorganisms in the pathogenesis of sarcoidosis?
du Bois RM, Goh N, McGrath D, Cullinan P.
Sarcoidosis is a granulomatous disease that has the immunopathological features of being antigen-driven . It is a complex disease that appears to arise from the interaction of one or more triggers with an immunologically predisposed host . Previous reports of familial clustering and varying prevalence of sarcoidosis in different populations could reflect differences in ethnic predisposition or differences in local environmental exposures . This review focuses specifically on these areas that have been the subjects of intensive investigation recently . Specific focus is provided on the issue of an infective trigger and highlights popular candidates . It is concluded that microbes are a likely trigger (but not as an infection) in a genetically predisposed individual and that this initial event culminates in the sarcoidosis granulomatous response.

Cell Transplant, 2002, 11(8), 787 - 97
Development of a novel cytomedical treatment that can protect entrapped cells from host humoral immunity; Suzuki R et al.; Cell therapy is expected to relieve the shortage of donors needed for organ transplantation . When patients are treated with allogeneic or xenogeneic cells, it is necessary to develop a means by which to isolate administered cells from an immune attack by the host . We have developed "cytomedicine," which consists of functional cells entrapped in semipermeable polymer, and previously reported that alginate-poly-L-lysine-alginate microcapsules and agarose microbeads could protect the entrapped cells from injury by cellular immunity . However, their ability to isolate from humoral immunity was insufficient . It is well known that the complement system plays an essential role in rejection of transplanted cells by host humoral immunity . Therefore, the goal of the present study was to develop a novel cytomedical device containing a polymer capable of inactivating complement . In the screening of various polymers, polyvinyl sulfate (PVS) exhibited high anticomplement activity and low cytotoxicity . Murine pancreatic beta-cell line (MIN6 cell) entrapped in agarose microbeads containing PVS maintained viability and physiological insulin secretion, replying in response to glucose concentration, and resisted rabbit antisera in vitro . PVS inhibited hemolysis of sensitized sheep erythrocytes (EAs) and rabbit erythrocytes by the complement system . This result suggests that PVS inhibits both the classical and alternative complement pathways of the complement system . Next, the manner in which PVS exerts its effects on complement components was examined . PVS was found to inhibit generation of C4a and Ba generation in activation of the classical and alternative pathways, respectively . Moreover, when the EAC1 cells, which were carrying C1 on the EAs, treated with PVS were exposed to C1-deficient serum, hemolysis decreased in a PVS dose-dependent manner . These results suggest that PVS inhibits C1 in the classical pathway and C3 convertase formation in the alternative pathway . Therefore, PVS may be a useful polymer for developing an anticomplement device for cytomedical therapy.

J Hosp Infect, 2003 Feb, 53(2), 124 - 8
Comparison of the disinfectant efficacy of Perasafe and 2% glutaraldehyde in in vitro tests; Vizcaino-Alcaide MJ et al.; Two percent glutaraldehyde has been the reference disinfectant for high-level disinfection, but its frequent association with adverse effects has stimulated a search for newer disinfectants . We compared the efficacy of 2% glutaraldehyde with that of a new disinfectant formulation, Perasafe (0.2% peracetic acid) in six in vitro tests: germicidal effect in a suspension of micro-organisms; using a microbe-contaminated metallic endodoncy file; an endoscope model; a modified capacity test; a sporicidal test, and corrosiveness on metallic instruments . Both products were effective germicides in 10-20 min, completely destroying microbial inocula except for Mycobacterium and spores . Internal irrigation of endoscopes with 100 mL of either was totally effective . Both substances resisted inactivation after repeated inoculation and did not corrode clean instruments; however, when organic matter was added the 0.2% peracetic acid formulation cleaned without corrosion, while 2% glutaraldehyde fixed the matter to the scalpel, causing corrosion within 2 h . In summary, Perasafe is a good substitute for 2% glutaraldehyde for high-level disinfection .

Gut, 2003 Mar, 52(3), 439 - 51
Intestinal epithelial responses to enteric pathogens: effects on the tight junction barrier, ion transport, and inflammation; Berkes J et al.; The effects of pathogenic organisms on host intestinal epithelial cells are vast . Innumerable signalling pathways are triggered leading ultimately to drastic changes in physiological functions . Here, the ways in which enteric bacterial pathogens utilise and impact on the three major physiological functions of the intestinal epithelium are discussed: alterations in the structure and function of the tight junction barrier, induction of fluid and electrolyte secretion, and activation of the inflammatory cascade . This field of investigation, which was virtually non-existent a decade ago, has now exploded, thus rapidly expanding our understanding of bacterial pathogenesis . Through increased delineation of the ways in which microbes alter host physiology, we simultaneous gain insight into the normal regulatory mechanisms of the intestinal epithelium.

Med Hypotheses, 2003 Mar, 60(3), 315 - 20
Failure of blood-thymus barrier as a mechanism of tumor and trophoblast escape; Bubanovic IV; A major process through which the immune system becomes tolerant to self-proteins involves the deletion of self-reactive clones in the thymus, but clonal deletion is not single mechanisms of thymic tolerance . There is now much evidence that intrathymic antigen expression results in anergy induction of T helper type-1 (Th1) clones in the periphery . Blood-thymus barrier is most important structure for prevention of unwanted penetration of antigens into the thymus . Impermeability of the barrier restrain induction of acquired thymic tolerance on unwanted antigens like microbes and tumor cells . Nevertheless, one of most important mechanism of tumor and trophoblast escape is in anergy of Th1 cells and in Th2 cells domination . Many mechanisms are included in disarrangement of Th1/Th2 balance in pregnancy and tumor bearers, but one of possibility is in failure of blood-thymus barrier . Possible consequences of blood-thymus barrier failure are trophoblast-specific or tumor-specific antigens penetrate into the thymus, deletion or anergy of antigen-specific clones and acquired thymic tolerance induction . Blood-thymus barrier is variable structure in anatomical and functional sense so that in certain condition foreign antigens probably can permeate across the barrier . Probability that some factors like hormones, cytokines, prostaglandine and neuromediators can affect blood-thymus barrier permeability and contribute in mechanisms of trophoblast and tumor escape is real but relatively unexplored.

Allergy, 2003 Jan, 58(1), 62 - 6
In vitro kinetics of allergen- and microbe-induced IL-4 and IFN-gamma mRNA expression in PBMC of pollen-allergic patients; Laaksonen K et al.; BACKGROUND: According to a hypothesis allergens induce Th2 responses in allergic patients, and microbes induce Th1 responses . We studied the kinetics of in vitro allergen-, tuberculin (PPD)- and tetanus toxin (TT)-induced IFN-gamma and IL-4 mRNA expression in peripheral blood mononuclear cell (PBMC) cultures of pollen-allergic patients and healthy controls . METHODS: PBMC of 10 birch or timothy pollen-allergic patients and of 13 healthy controls were stimulated in vitro with allergen (birch or timothy), PPD or TT . Pellets and supernatants were collected at 24, 48, 72 and 96 h after stimulation . IFN-gamma and IL-4 production was measured by enzyme linked immunosorbent assay and mRNA expression using RT-PCR and time-resolved fluorometry . RESULTS: Allergen induced IFN-gamma production and mRNA expression in PBMC more in allergic patients than in healthy controls . Also allergen induced IL-4 mRNA expression more in allergic patients than in healthy controls . PPD induced IFN-gamma mRNA expression both in allergic patients and healthy controls, whereas IFN-gamma production was induced only in healthy controls and IL-4 was not induced at all . TT induced IFN-gamma mRNA expression in both groups, IFN-gamma production in allergic patients, and IL-4 mRNA expression in both allergic patients and healthy controls . CONCLUSIONS: In vitro stimulation with allergen induced both IFN-gamma and IL-4 mRNA expression of PBMC in allergic patients . These observations challenge the clearcut division of microbe-specific Th1 and allergen-specific Th2 responses in peripheral blood.

Adv Space Res, 2003, 31(1), 103 - 7
Planetary protection and the search for life beneath the surface of Mars; Mancinelli RL; The search for traces of extinct and extant life on Mars will be extended to beneath the surface of the planet . Current data from Mars missions suggesting the presence of liquid water early in Mars' history and mathematical modeling of the fate of water on Mars imply that liquid water may exist deep beneath the surface of Mars . This leads to the hypothesis that life may exist deep beneath the Martian surface . One possible scenario to look for life on Mars involves a series of unmanned missions culminating with a manned mission drilling deep into the Martian subsurface (approximately 3Km), collecting samples, and conducting preliminary analyses to select samples for return to earth . This mission must address both forward and back contamination issues, and falls under planetary protection category V . Planetary protection issues to be addressed include provisions stating that the inevitable deposition of earth microbes by humans should be minimized and localized, and that earth microbes and organic material must not contaminate the Martian subsurface . This requires that the drilling equipment be sterilized prior to use . Further, the collection, containment and retrieval of the sample must be conducted such that the crew is protected and that any materials returning to earth are contained (i.e., physically and biologically isolated) and the chain of connection with Mars is broken . c2002 COSPAR . Published by Elsevier Science Ltd . All rights reserved.

Biol Neonate, 2003, 83(2), 85 - 96
Chorioamnionitis: a risk factor for fetal and neonatal morbidity; Bracci R et al.; Despite widespread use of drugs to arrest preterm labor, there has been no decrease in the numbers of low-birth-weight or preterm infants in the last 20 years . Evidence from many sources links preterm birth to symptomatic and subclinical infections . Recently, an increasing body of evidence has suggested that not only is subclinical infection responsible for preterm birth but also for many serious neonatal sequelae, including periventricular leukomalacia, cerebral palsy, respiratory distress and even bronchopulmonary dysplasia and necrotizing enterocolitis . Proxies of intrauterine infection include clinical chorioamnionitis, histological chorioamnionitis and intraamniotic increase in cytokines, which have been found to be associated with acute neonatal morbidity and mortality and, at least to some degree, with neurological impairment, chronic lung disease and thymus involution in the preterm infant . The infectious/inflammatory mechanisms involved are not fully understood, and the types of microbes and genetic features of host adaptive and innate immune responses need to be better characterized .

Appl Environ Microbiol, 2003 Feb, 69(2), 1206 - 13
Biotin limitation in Sinorhizobium meliloti strain 1021 alters transcription and translation; Heinz EB et al.; Most Sinorhizobium meliloti strains lack several key genes involved in microbial biotin biosynthesis, and it is assumed that this may be a special adaptation which allows the microbe to down-regulate metabolic activities in the absence of a host plant . To further explore this hypothesis, we employed two different strategies . (i) Searches of the S . meliloti genome database in combination with the construction of nine different gusA reporter fusions identified three genes involved in a biotin starvation response in this microbe . A gene coding for a protein-methyl carboxyl transferase (pcm) exhibited 13.6-fold-higher transcription under biotin-limiting conditions than cells grown in the presence of 40 nM biotin . Consistent with this observation, biotin-limiting conditions resulted in a significantly decreased survival of pcm mutant cells compared to parental cells or cells grown in the presence of 40 nM biotin . Further studies indicated that the autoinducer synthase gene, sinI, was transcribed at a 4.5-fold-higher level in early stationary phase in biotin-starved cells than in biotin-supplemented cells . Lastly, we observed that open reading frame smc02283, which codes for a putative copper resistance protein (CopC), was 21-fold down-regulated in response to biotin starvation . (ii) In a second approach, proteome analysis identified 10 proteins which were significantly down-regulated under the biotin-limiting conditions . Among the proteins identified by using matrix-assisted laser desorption ionization-time of flight mass spectrometry were the varpi subunit of the RNA polymerase and the 50S ribosomal protein L7/L12 (L8) subunit, indicating that biotin-limiting conditions generally affect transcription and translation in S . meliloti.

Curr Pharm Des, 2003, 9(1), 1 - 5
Intestinal epithelial toll-like receptors: to protect . And serve?
Gewirtz AT.
The innate immune system uses a series of pattern recognition receptors to detect the presence of pathogens thus allowing for rapid host defense responses to invading microbes . A key component of such receptors are the "toll-like receptors" (TLRs), which recognize a panel of microbial molecules that tend to be somewhat invariant, at least in select regions, thus permitting a relatively small number of receptors to recognize a large number of different microbes . Accordingly, this panel of TLRs bears little ability to distinguish between commensal and pathogenic microbes as such organisms generally bear far more structural similarities than differences between them . For the professional phagocytic cells classically considered to be the primary mediators of innate immunity such distinction between commensal and pathogenic microbes is not particularly important since any microbe that breaches the outer host defensive barriers to reach these phagocytes, whether doing so by a pathogen-specific or opportunistic mechanism, is likely potentially hazardous to its host . However, epithelial cells that line mucosal surfaces, thus being on the front line of host defense, also play an active role in innate immunity particularly by secreting chemokines and other immune mediators in response to pathogenic microbes . Epithelial cells have been reported to express several TLRs suggesting these receptors play a role in intestinal epithelial innate immune signaling pathways . However, since some mucosal surfaces such as the intestinal epithelium are normally densely colonized by a wide variety of microbes, the ability to distinguish the occasional pathogen from the sea of commensals presents an important challenge . This minireview considers the current findings regarding TLR expression in the intestinal epithelium and the role these receptors might serve in host defense.

J Microencapsul, 2002 Nov-Dec, 19(6), 725 - 35
A new microencapsulation device for controlled membrane and capsule size distributions; Ceausoglu I et al.; Microbeads and microcapsules, employed for the microencapsulation of bioactive material, should provide sufficient mechanical protection to the encapsulated material, insure an optimal diffusion of desired molecules and, for transplantation-related applications, block the ingress of the imunoagents . Microcapsules are also often required to be smooth, spherical, within narrow size and membrane thickness distributions . In addition, the bioactive material has to be centred within the capsule, whose size should be minimized in relation to the bioactive material in order to optimise the diffusion of active molecules . The production process of such microcapsules should respect the aforementioned constraints and, in addition, be sterile, repeatable, robust, and harmless to the bioactive material while showing a high output . Two prototypes, dedicated to the microencapsulation of bioactive materials are presented . A semi-manual device permits the control of microcapsule properties for small scale (< 10 000 microcapsules), sterile production . An 'automated reaction control' system has also been developed . The features of the former are demonstrated for the repeatable production of 400 microm-microcapsules using the alginate/cellulose sulphate/poly(methylene-co-guanidine) system . The production rate is 500 000 microcapsules/h, with a size distribution within +/-10% and membrane thickness distribution within +/-5 microm . The latter in particular is, to the authors' knowledge, better than can be achieved with currently disclosed technologies, and is due to the precise control of the reaction conditions and time.

Novartis Found Symp, 2002, 248, 76 - 88; discussion 88-93, 277-82
Respiratory tract mucins: structure and expression patterns; Davies JR et al.; Goblet cells produce mainly MUC5AC, but also MUC5B and some MUC2 in apparently 'irritated' airways . MUC5B dominates in the submucosal glands although a little MUC5AC and MUC7 are usually present . MUC4 originates from the ciliated cells . After separation into a gel and a sol phase, lysozyme and lactoferrin are enriched in the salivary gel phase suggesting that mucus may act as a matrix for 'protective' proteins on the mucosal surface . A salivary MUC5B N-terminal fragment consistent with a cleavage event in the D' domain was detected with antibodies against various N-terminal peptide sequences suggesting that assembly of MUC5B occurs through a mechanism similar to that of the von Willebrand factor . Identification of additional cleavage sites C-terminal to the D' domain suggests that most of the N-terminal low-glycosylated part of MUC5B may be removed without affecting the oligomeric nature of the mucin . Possibly, the generation of mucins with different macromolecular properties through proteolytic 'processing' is one way of adapting the mucus polymer matrix to meet local physiological demands . Monomeric mucins that appear to turn over rapidly in the airway epithelium have been identified using radiolabelled mucin precursors . 'Shedding' of such mucins after microbe attachment may prevent colonization of epithelial surfaces.

Plant Cell, 2003 Feb, 15(2), 331 - 45
Regulation of actin-dependent cytoplasmic motility by type II phytochrome occurs within seconds in Vallisneria gigantea epidermal cells; Takagi S et al.; The effects of light on actin-dependent cytoplasmic motility in epidermal cells of green leaves of the aquatic angiosperm Vallisneria gigantea were investigated quantitatively using a custom-made dynamic image analyzer . Cytoplasmic motility was measured by monitoring changes in the brightness of individual pixels on digitized images taken sequentially under infrared light . Acceleration and deceleration of cytoplasmic motility were regulated photoreversibly by type II phytochrome(s) . This phytochrome-dependent induction of cytoplasmic motility did not occur uniformly in cytoplasm but took place as scattered patches in which no particular organelles, including nucleus, existed . The induction became detectable at 2.5 s after the start of irradiation with pulsed red light . In cells exposed to microbeam irradiation, cytoplasmic motility was induced only in sites in the cytoplasm that were irradiated directly, whereas nonirradiated neighboring areas were unaffected . The effect was short-lived, disappearing within a few minutes, and no signal was transmitted from an irradiated cell to its neighbors . Anti-phytochrome antibody-responsive protein(s) was detectable in the leaf extract by immunoblot and zinc blot analyses and in cryosections of the epidermis by immunocytochemistry . Although the phytochrome-dependent cytoplasmic motility was blocked by exogenously applied latrunculin B or cytochalasins, treatment of the dark-adapted cells with Ca(2+)-chelating reagents induced the cytoplasmic motility . We have proposed a model for the phytochrome regulation of cytoplasmic motility as one of the earliest responses to a light stimulus.

J Med Genet, 2003 Feb, 40(2), 104 - 8
Association of the CD14 gene -159C polymorphism with progression of IgA nephropathy; Yoon HJ et al.; The risk factors associated with the progression of IgA nephropathy (IgAN), the most common form of glomerulonephritis, are unclear . It has been suggested that CD14 signalling in response to various microbes affects the natural history of chronic inflammatory conditions . It has been hypothesised that variants in the promoter region of the CD14 gene might alter the expression of CD14, and this in turn could influence the progressive nature of IgAN . PCR-RFLP was used to determine the polymorphism at the -159 site (T to C) . The distribution of the CD14/-159 polymorphism was no different in patients with IgAN (n=216) compared to 171 healthy controls . After follow up for 86 months, it was found that an excess of the C genotype occurred in patients with progressive disease (p=0.03) and the risk of disease progression increased as the number of C alleles increased (p for trend = 0.002) . The hazard ratio for progression in the patients with the CC genotype was 3.2 (p=0.025) compared with the patients possessing the TT genotype . After LPS stimulation, sCD14 was released more abundantly from the PBMCs of the TT subjects than from that of the CC subjects (p=0.006), even though mCD14 expression level was no different . In addition, the TT subjects released less IL-6 than the CC subjects after stimulation (p=0.0003) . These results suggest that the CD14/-159 polymorphism is an important marker for the progression of IgAN and may modulate the level of the inflammatory responses.

Nat Rev Immunol, 2003 Feb, 3(2), 169 - 76
Innate immune sensing and its roots: the story of endotoxin; Beutler B et al.; How does the host sense pathogens? Our present concepts grew directly from longstanding efforts to understand infectious disease: how microbes harm the host, what molecules are sensed and, ultimately, the nature of the receptors that the host uses . The discovery of the host sensors--the Toll-like receptors--was rooted in chemical, biological and genetic analyses that centred on a bacterial poison, termed endotoxin.

Ying Yong Sheng Tai Xue Bao, 2002 Sep, 13(9), 1077 - 80
{Biological characteristics of different forest soils in Nanjing-Zhenjiang mountan area}; Xiao C et al.; Studies on the biological characteristics, including soil microbe, soil enzyme activity, soil nutritient content, and litter decomposition of different forest soils in Nanjing-Zhenjiang mountain area showed that the amounts of microbes and the activities of six enzymes in forest soils changed regularly in different forests during different months . The contents of nutritional elements varied regularly with forest growth bio-cycles, and were inerrelated prominently with the amounts of soil microbes and the activities of soil enzymes . There existed temporal-spatial differences in the decomposition rate of litters and the reverted velocity of nutrients among different forests . The comparisons of various biological characteristics among secondary Quercus variabilis forest, Phllostachys pubescens forest, and Cunninghamia lanceolata forest indicated that secondary Quercus variabilis forest had the most abundant nutrients in soil, and possessed the strongest ability of self-fertilization . Therefore, to construct coniferous forests with broadleaf trees in this area could avoid or abate the decline of soil fertility.

Arch Biochem Biophys, 2003 Feb 1, 410(1), 121 - 33
The interaction of sodium chlorite with phospholipids and glutathione: a comparison of effects in vitro, in mammalian and in microbial cells; Ingram PR et al.; In this study the interaction of the preservative sodium chlorite with unsaturated lipids and glutathione was investigated, in comparison with peroxides, sodium hypochlorite, and benzalkonium chloride . The aim was to determine whether the action of sodium chlorite could involve membrane lipid damage or antioxidant depletion, and how this related to toxicity in both mammalian and microbial cells . The treatment of phospholipids with chlorite yielded low levels of hydroperoxides, but sodium chlorite oxidized the thiol-containing antioxidant glutathione to its disulfide form very readily in vitro, with a 1:4 oxidant:GSH stoichiometry . In cultured cells, sodium chlorite also caused a substantial depletion of intracellular glutathione, whereas lipid oxidation was not very prominent . Sodium chlorite had a lower toxicity to ocular mammalian cells than benzalkonium chloride, which could be responsible for the different effects of long-term application in the eye . The fungal cells, which were most resistant to sodium chlorite, maintained higher percentage levels of intracellular glutathione during treatment than the mammalian cells . The results show that sodium chlorite can cause oxidative stress in cells, and suggest that cell damage is more likely to be due to interaction with thiol compounds than with cell membrane lipids . The study also provides important information about the differential resistance of ocular cells and microbes to various preservatives and oxidants.

Mech Dev, 2003 Feb, 120(2), 185 - 98
Wolbachia distribution and cytoplasmic incompatibility during sperm development: the cyst as the basic cellular unit of CI expression; Clark ME et al.; The growth and distribution of the intracellular microbe Wolbachia pipientis during spermatogenesis in several different host/symbiont genetic combinations in Drosophila melanogaster and Drosophila simulans is described . Considerable intra- and inter-strain variation in Wolbachia density and tissue distribution was observed . Wolbachia were found inside spermatocytes and spermatids or within the somatic cyst cells surrounding the germ cells . Some strains displayed both tissue distributions . High rates of cytoplasmic incompatibility (CI) are correlated with high levels of Wolbachia only when spermatocytes and/or spermatids harbor the microbe . Wolbachia infection of somatic cyst cells, although sometimes present at high levels, did not result in significant CI expression . CI-inducing Wolbachia strains within D . simulans showed no distinguishable differences in distribution or density within infected spermatids . To dissect the relative contribution of host and symbiont to the expression of CI, Wolbachia from various host strains known to exhibit varying levels of CI were introgressed into new uninfected host genetic backgrounds . These introgression experiments confirm that the mod(+)/mod(-) phenotype is an intrinsic Wolbachia trait and is not determined by host factors . The level of sperm modification in those lines harboring Wolbachia capable of modifying sperm, however, is influenced by host genetic background . These results form the basis of the Wolbachia Infected Spermatocyte/Spermatid Hypothesis (WISSH) . According to WISSH, Wolbachia infection in spermatocytes and then spermatids during sperm development is required for CI expression.

Genes Cells, 2003 Jan, 8(1), 51 - 63
Antagonistic and agonistic effects of an extracellular fragment of nectin on formation of E-cadherin-based cell-cell adhesion; Honda T et al.; BACKGROUND: Nectin is a Ca2+-independent immunoglobulin-like cell-cell adhesion molecule at the E-cadherin-based cell-cell adherens junctions (AJs), and comprises a family consisting of four members, nectin-1, -2, -3, and -4 . Nectin and E-cadherin are associated with afadin and alpha-catenin, actin filament (F-actin)-binding proteins connecting respective adhesion molecules to the actin cytoskeleton, but the role of nectin in the formation of the E-cadherin-based cell-cell AJs has not yet been fully understood . To obtain evidence for this role of nectin, we attempted to develop an antagonist and/or agonist of nectin . RESULTS: We made a recombinant extracellular fragment of nectin-3 (Nef-3) . Nef-3 trans-interacted with cellular nectin-1 and thereby diminished the formation of the nectin-1-based cell-cell adhesion . This resulted in a reduction of the formation of the E-cadherin-based cell-cell adhesion in L fibroblasts stably expressing both exogenous nectin-1alpha and E-cadherin (nectin-1-EL cells) and MDCK cells stably expressing exogenous nectin-1alpha (nectin-1-MDCK cells) . This antagonistic effect of Nef-3 was also observed in L cells stably expressing exogenous E-cadherin alone (EL cells) and wild-type MDCK cells . Conversely, Nef-3 coated on microbeads first recruited the nectin-afadin complex and then the E-cadherin-catenin complex to the bead-cell contact sites in nectin-1-EL and nectin-1-MDCK cells . CONCLUSION: These results suggest that nectin is necessary and sufficient for the recruitment of E-cadherin to the nectin-based cell-cell adhesion sites and involved in the formation of E-cadherin-based cell-cell AJs.

Ying Yong Sheng Tai Xue Bao, 2002 Oct, 13(10), 1358 - 9
{Effect of free-air CO2 enrichment on soil microbe in paddy field}; Xu G et al.; Utilizing FACE research site in Anzhen of Wuxi, the effect of CO2 concentration increasing on soil microbe was studied in a paddy field under the condition of local cultivation, irrigation and fertilization . The results showed that soil respiration intensity was 31.88 ml.kg-1 and bacteria number was 1.51 x 10(6) ind.g-1 dry soil in FACE area, which were greater than those in control area (soil respiration intensity 27.83 ml.kg-1, bacteria number was 1.25 x 10(6) ind.g-1 dry soil, but the differences were not significant.

Ying Yong Sheng Tai Xue Bao, 2002 Oct, 13(10), 1323 - 38
{Responses of agricultural crops of free-air CO2 enrichment}; Kimball BA et al.; Over the past decade, free-air CO2 enrichment (FACE) experiments have been conducted on several agricultural crops: wheat(Triticum aestivum L.), perennial ryegrass (Lolium perenne), and rice(Oryza sativa L.) which are C3 grasses; sorghum (Sorghum bicolor (L.) Moench), a C4 grass; white clover (Trifolium repens), a C3 legume; potato (Solanum tuberosum L.), a C3 forb with tuber storage; and cotton (Gossypium hirsutum L.) and grape (Vitis vinifera L.) which are C3 woody perennials . Using reports from these experiments, the relative responses of these crops was discussed with regard to photosynthesis, stomatal conductance, canopy temperature, water use, water potential, leaf area index, shoot and root biomass accumulation, agricultural yield, radiation use efficiency, specific leaf area, tissue nitrogen concentration, nitrogen yield, carbohydrate concentration, phenology, soil microbiology, soil respiration, trace gas emissions, and soil carbon sequestration . Generally, the magnitude of these responses varied with the functional type of plant and with the soil nitrogen and water status . As expected, the elevated CO2 increased photosynthesis and biomass production and yield substantially in C3 species, but little in C4, and it decreased stomatal conductance and transpiration in both C3 and C4 species and greatly improved water-use efficiency in all the crops . Growth stimulations were as large or larger under water-stress compared to well-watered conditions . Growth stimulations of non-legumes were reduced at low soil nitrogen, whereas elevated CO2 strongly stimulated the growth of the clover legume both at ample and under low N conditions . Roots were generally stimulated more than shoots . Woody perennials had larger growth responses to elevated CO2, while at the same time, their reductions in stomatal conductance were smaller . Tissue nitrogen concentrations went down while carbohydrate and some other carbon-based compounds went up due to elevated CO2, with leaves and foliage affected more than other organs . Phenology was accelerated slightly in most but not all species . Elevated CO2 affected some soil microbes greatly but not others, yet overall activity appears to be stimulated . Detection of statistically significant changes in soil organic carbon in any one study was impossible, yet combining results from several sites and years, it appears that elevated CO2 did increase sequestration of soil carbon . Whenever possible, comparisons were made between the FACE results and those from prior chamber-based experiments reviewed in the literature . Over all the data and parameters considered in this review, there are only two parameters for which the FACE- and chamber-based data appear to be inconsistent . One is that elevated CO2 from FACE appears to reduce stomatal conductance about one and a half times more than observed in prior chamber experiments . Similarly, elevated CO2 appears to have stimulated root growth relatively more than shoot growth under FACE conditions compared to chamber conditions . Nevertheless, for the most part, the FACE- and chamber-based results have been consistent, which gives confidence that conclusions drawn from both types of data are accurate . However, the more realistic FACE environment and the larger plot size have enabled more extensive robust multidisciplinary data sets to be obtained under conditions representative of open fields in the future high-CO2 world.

Med Parazitol (Mosk), 2002 Oct-Dec, (4), 54 - 8
{The range of pathogen variation due to discussion of different hypotheses of plaque}; Anisimov PI et al.; The paper reviews the hypotheses that explain the mechanism of plague enzooty in natural foci, which are based on a concept of a wide range of plague microbial variability . A comparative analysis of the parameters of variability in the experimentally obtained plague microbial strains and "atypical" natural isolates of the causative agent has led to the conclusion that the mechanism of adaptive variability is due to a phenotypic change in ontogenesis that reflects the philogenetic pathway of the adaptability of a plague microbe to constantly changing living conditions in the ecological niche assimilated by the causative agent.

Wei Sheng Wu Xue Bao, 2002 Aug, 42(4), 478 - 83
{Community constitute and phylogenetic analysis on soil uncultured microorganism}; Chen H et al.; Many evidences show bachteria that can be cultured in lab are only the minority of germs existing in nature . Most of bacteria, containing rich valuable gene resource, are unknown for they are uncultured . To research these uncultured bacteria, Directly extract crude DNA from farm soil, separate 16S rDNA mixture amplified by PCR from the crude DNA, sequence it and compare the sequences with the records of NCBI to classify the germs . The significant microbe community difference from respective soil, which have possibility in developing a new tool for researching soil bacteria diversity were finded.

Int J Radiat Biol, 2003 Jan, 79(1), 43 - 52
Biophysical model of the radiation-induced bystander effect; Nikjoo H et al.; PURPOSE: To construct a quantitative model of the radiation-induced bystander effect based on diffusion-type spreading of bystander signal communication between the hit and non-hit cells . Cell inactivation and induced oncogenic transformation by broad- and microbeam irradiation systems are considered . MATERIALS AND METHODS: The biophysical model ByStander Diffusion Modelling (BSDM) postulates that the oncogenic bystander response observed in non-hit cells originates from specific signals received from inactivated cells . The bystander signals are assumed to be protein-like molecules spreading in the culture media by Brownian motion . The bystander signals are assumed to switch cells into a state of cell death (apoptotic/mitotic/necrosis) or induced oncogenic transformation modes . RESULTS: The bystander cell survival observed after treatment with the irradiated conditioned medium (ICM) using the broad-beam and the microbeam irradiation modalities were analysed and interpreted in the framework of the BSDM model . The model predictions for cell inactivation and induced oncogenic transformation frequencies agree well with observed data from micro and broad-beam experiments . In the case of irradiation with constant fraction of cells, transformation frequency for the bystander effect increases with increasing radiation dose . CONCLUSIONS: Bystander modelling based on diffusion of signals is in good agreement with experimental cell survival data and induced oncogenic transformation frequencies . The data confirm the protein-like nature of the bystander signal . Linear extrapolation of the cell response to low doses of radiation might underestimate carcinogenic risk, for example for domestic radon hazards, if the contribution from the bystander effect is neglected . The BSDM predicts that the bystander effect cannot be interpreted solely as a low-dose effect phenomenon . It is shown that the bystander component of radiation response can increase with dose and be observed at high doses as well as at low doses . The validity of this conclusion is supported by analysis of experimental results from high-linear energy transfer microbeam experiments.

Wei Sheng Wu Xue Bao, 1999 Jun, 39(3), 264 - 7
{The isolation of microbe producing biosurfactants}; Pan B et al.; Microorganisms capable of producing biosurfactants can be isolated by a series of steps including hydrocarbon enrichment culture, hemolytic activity assay on blood agar plates and oil displacement activity assay etc . Ten strains(including bacteria, yeasts and fungi) were isolated with higher surface activity from 1000 samples from soil, sludge, waste water etc . Two strains of bacteria produced rhamnolipids and trehaloselipids respectively . One strain of bacterium produced long chain unsaturated carboxylic acid and another produced azelaic acid . Two strains of yeasts produced lipopolysaccharides with excellent emulsification property.

Medicina (Kaunas), 2002, 38(12), 1220 - 3
{Technology and analysis of Ginkgo tincture}; Bernatoniene J et al.; The article deals with the production of the tincture of Ginkgo leaves while selecting extractant, the size of particles in a raw material, and the method of extraction . The optimal concentration of the extract was established by experiment and was the following: ethanol of 70 percent (V/V), the particles size 2-3 mm, the production method percolation, and the flow speed of tincture 0.5 ml/min . The tinctura was analyzed at determination of the sum of flavonoids in terms of quercetin, dry residue, the concentration of ethanol, density, refraction index, heavy metals and microbe pollution . The stability of the tincture and its expiry date were fixed.

Waste Manag Res, 2002 Dec, 20(6), 494 - 500
Kinetics of CH4 oxidation in mixed culture; Dote Y; Microbial cultures used for methane oxidation experiments were prepared by enriching under a 20 % CH4 atmosphere either leachate extracts from two different landfill sites or a digested sewage sludge . No microbes were axenically isolated, therefore the cultures were mixtures of CH4 oxidising and other aerobic microorganisms . CH4 oxidation experiments were carried out with a batch reactor, whose change in gas volume could be measured . A mixture of air and methane with CH4 concentrations ranging from 5 to 20 % was introduced into the reactor . Methane oxidation rate was expressed as a Monod equation for CH4 and a first order reaction for O2 . Maximum oxidation rate (Vmax) resulted 2.1 x 10(-13) to 3.4 x 10(-11) hr(-1) cell(-1), and half saturation constant (KM) was 5.1 x 10(-5) to 6.5 x 10(-4) mol L(-1) . The molar ratio of consumed O2 to oxidised CH4 was 1.5-1.8

J Environ Qual, 2003 Jan-Feb, 32(1), 55 - 62
The potential of rhizosphere microbes isolated from a constructed wetland to biomethylate selenium; Azaizeh HA et al.; The potential of rhizosphere microbes isolated from common reed {Phragmites australis (Cav.) Trin . ex Steud} plants grown in a subsurface-flow constructed wetland to biomethylate selenate or selenite was studied in liquid cultures under controlled conditions . Total mean percentages of volatilized Se from half-strength Hoagland culture solutions (low C content) supplemented with selenate or selenite and inoculated with cultured rhizosphere microbes after 15 d of incubation were 7.9 and 49.1%, respectively . There was a relative best fit (r = 0.87) between total number of rhizosphere and cultured microbes and the percentage of volatilized Se in Hoagland solution after 15 d of incubation . However, when the same microbes were cultured in tryptic soybean broth (TSB) medium (high C content), the percentages of volatilized Se from selenate and selenite were 1.3 and 1.9%, respectively . The volatilization percentages of Se from selenate or selenite in culture solutions inoculated with rhizosphere suspension instead of cultured rhizosphere microbes were very low (1.2-3.0%) in both cultivation media . In all experiments, selenite was volatilized significantly (p < 0.05) in higher amounts by cultured rhizosphere microbes after 15 d of incubation compared with selenate . Dissolved biomethylated dimethylselenide (DMSe) in water samples taken from the subsurface-flow bed was determined by purging with helium . The DMSe in water samples was indirectly detected up to 2.4 microg Se L(-1), which indicates that part of the produced DMSe was dissolved in the matrix before being released into the atmosphere . Our results show that rhizosphere microbes isolated from common reed plants have a high potential of Se biomethylation and volatilization from selenate and selenite.

Wei Sheng Wu Xue Bao, 2001 Jun, 41(3), 278 - 86
{Studies on the isolation, culture and DNA identification of mycelia of Tricholoma matsutake}; Zeng D et al.; The tissue isolation for Tricholom matsutake(S Ito et Imai) Sing were made with 8 media in 810 test tubes from different positions of 9 basidiocarps of different source and from mycorrhizae, and soil with the fungi in the studies . The results showed that 94 test tubes of slow-growing mycelia were isolated from lamellae and their success percentages of isolation with media PDAS, PDAW, BM, PDA were 74.4%, 355%, 15.6% and 8.9% respectively . The fast-growing mycelia were easily got from the mycorrhizae and soil related to matsutake . The isolates with different culture characteristics were appraised through DNA fingerprinting comparison with matsutake basidiocarps collected from Jilin province, China and reference isolates presented by matsutake research workers of China and Japan, in which RAPD (Random Amplified Polymorphic DNA)-PCR patterns were sharply prepared using 17 arbitrary decamer nucleotide primers screened . The statistical data indicated that all slow-growing mycelia isolated from lamellae had the same DNA fingerprinting patterns as their origin basidiocarps tissues such as pileus (containing lamellae) and stipe, whose similarity coeffecients all were 1.000, and were therefore identified as true Tricholoma matsutake . However, the fast-growing mycelia or yeast colony were identified as not matsutake . The results suggested that matsutake and its own mycelia have DNA homogeneity, and there exists no any other microbe in the basidiocarps . The results also demonstrated that all matsutake from east China and reference isolates of matsutake from southwest China and Japan were one same species Tricholoma matsutake, whose DNA similarity coeffecients varied from 0.934 to 0.994.

Am J Infect Control, 2003 Feb, 31(1), 13 - 7
Investigation of single-use versus reusable infectious waste containers as potential sources of microbial contamination; Neely AN et al.; BACKGROUND: Laws require that infectious waste be segregated from noninfectious waste . Companies certified to dispose of infectious waste offer both reusable and single-use containers . The focus of this study was to determine if there would be a microbiologic advantage to the use of one type of container over another in a burn hospital . METHODS: Monthly swab cultures were taken from the tops of >250 infectious waste containers during 2 years . Bacteria and fungi were identified . In a substudy swab cultures were taken from an area of reusable tops before and after cleaning to evaluate the efficacy of cleaning on both the number and type of microbes present . Infection rates for acute patients were compared before and after control measures were instituted to decrease microbial transfer from infectious waste containers to patients . RESULTS: Cultures taken from reusable boxes when received from the container company showed that >99% were contaminated with bacteria or fungi; most were normal environmental or skin flora, but some cultures showed microorganisms that can be potentially harmful to patients with compromised immunity . Wiping the lids with a phenolic disinfectant decreased both the total microbial load (P <.001) and the variety of microbes present (P <.001) . In contrast, only 10% of the incoming single-use boxes showed any contamination . Infection rates dropped from 5.8 to 3.2 per 100 burn patients (P <.05) after the institution of cleaning and other changes made to decrease the possibility of microbial transfer from the infectious waste boxes to the patients . CONCLUSIONS: Upon delivery, significantly fewer single-use infectious waste boxes were contaminated than reusable ones (P <.001) . Extra infection control measures were needed when reusable infectious waste boxes were used in areas housing patients with compromised immunity . Facilities need be aware of the possible contamination of reusable infectious waste containers with microorganisms capable of causing nosocomial infections in patients who are compromised.

Transplantation, 2003 Jan 15, 75(1), 43 - 9
Single human leukocyte antigen flow cytometry beads for accurate identification of human leukocyte antigen antibody specificities; Pei R et al.; BACKGROUND: It is difficult to assign antibody specificity for highly sensitized patients using a cell panel with multiple antigens per reaction . We describe here a single antigen bead panel for accurate identification of human leukocyte antigen (HLA) antibody specificities by flow cytometry . METHODS: A total of 110 single recombinant HLAs, including 34 A locus alleles, 57 B locus alleles, and 19 C locus alleles, were produced by a mammalian expression system . These single antigens were coated onto eight different colored microbeads, which were mixed together in one tube for simultaneous detection of HLA antibodies against eight different antigens per flow cytometry test . RESULTS: Single HLA reacted specifically with the serologically defined monoclonal antibodies . The single antigen panel provided higher resolution than the regular cell panel for antibody detection by uncovering the masked specificities . Single antigens also provided higher sensitivity than the multiple antigens coated onto beads for HLA antibody detection as demonstrated by serum dilution studies . In 10 sera from patients who had rejected a kidney transplant, single antigen beads identified antibodies to 31 of 35 antigens that were mismatched in the donor . Most important, none of the reactions were against antigens present in the recipient . CONCLUSION: An accurate and sensitive HLA antibody detection method is described using flow cytometry beads coated with single HLAs produced by recombinant technology . The single antigen beads should be useful in predicting negative crossmatch in highly sensitized organ recipients and highly sensitized patients requiring platelets.

J Infus Nurs, 2003 Jan-Feb, 26(1), 44 - 8
Skin flora and infection; Hadaway LC; Human skin provides a great living environment for the growth of microbes . The types and numbers of microbes vary according to the part of the human body and the age and gender of the individual . These microbes have a definite impact on the incidence of catheter-related infections . By understanding the process of how infections develop, appropriate choices can be made for techniques and methods that prevent these infections.

Mol Cell Proteomics, 2002 Dec, 1(12), 922 - 9
A microbead-based system for identifying and characterizing RNA-protein interactions by flow cytometry; Brodsky AS et al.; We present a high throughput, versatile approach to identify RNA-protein interactions and to determine nucleotides important for specific protein binding . In this approach, oligonucleotides are coupled to microbeads and hybridized to RNA-protein complexes . The presence or absence of RNA and/or protein fluorescence indicates the formation of an oligo-RNA-protein complex on each bead . The observed fluorescence is specific for both the hybridization and the RNA-protein interaction . We find that the method can discriminate noncomplementary and mismatch sequences . The observed fluorescence reflects the affinity and specificity of the RNA-protein interaction . In addition, the fluorescence patterns footprint the protein recognition site to determine nucleotides important for protein binding . The system was developed with the human protein U1A binding to RNAs derived from U1 snRNA but can also detect RNA-protein interactions in total RNA backgrounds . We propose that this strategy, in combination with emerging coded bead systems, can identify RNAs and RNA sequences important for interacting with RNA-binding proteins on genomic scales.

J Comp Neurol, 2003 Feb 24, 457(1), 67 - 74
Progressive recovery of learning during regeneration of a single synapse in the medicinal leech; Burrell BD et al.; The leech escape reflex-shortening of the body-can change with nonassociative conditioning, including sensitization, habituation, and dishabituation . Capacity for sensitization, which is an enhancement of the reflex, is lost when a single S-interneuron is ablated, but the reflex response itself remains . In the present experiments, the S-interneuron's axon in the living leech was filled with 6-carboxyfluorescein (6-CF) dye and cut with an argon laser microbeam (lambda = 488 nm) . In contrast to sham-operated animals, axotomized preparations did not sensitize, reflecting the key role of the S-cell . By 2 weeks or more, S-cell axons had regenerated and reestablished synapses at their usual locations with neighboring S-cells . By 4 weeks, this restored the ability to sensitize to a level indistinguishable from that of controls, but an intermediate state of recovery was seen from 2-3 weeks after injury-a period not previously examined . The small capacity for sensitization among newly regenerated preparations was significantly lower than in sham controls but appeared higher than in animals whose cut S-cell axon had not regenerated its synapse . The results confirm the crucial role of the S-cell in sensitization . Moreover, full sensitization does not occur immediately upon synapse regeneration .

Comp Hepatol . 2003 Jan 3;2(1):1.
Liver sinusoidal endothelial cells represents an important blood clearance system in pigs; Nedredal GI et al.; BACKGROUND: Numerous studies in rats and a few other mammalian species, including man, have shown that the sinusoidal cells constitute an important part of liver function . In the pig, however, which is frequently used in studies on liver transplantation and liver failure models, our knowledge about the function of hepatic sinusoidal cells is scarce . We have explored the scavenger function of pig liver sinusoidal endothelial cells (LSEC), a cell type that in other mammals performs vital elimination of an array of waste macromolecules from the circulation . RESULTS: 125I-macromolecules known to be cleared in the rat via the scavenger and mannose receptors were rapidly removed from the pig circulation, 50% of the injected dose being removed within the first 2-5 min following injection . Fluorescently labeled microbeads (2 &mgr;m in diameter) used to probe phagocytosis accumulated in Kupffer cells only, whereas fluorescently labeled soluble macromolecular ligands for the mannose and scavenger receptors were sequestered only by LSEC . Desmin-positive stellate cells accumulated no probes . Isolation of liver cells using collagenase perfusion through the portal vein, followed by various centrifugation protocols to separate the different liver cell populations yielded 280 x 107 (range 50-890 x 107) sinusoidal cells per liver (weight of liver 237.1 g (sd 43.6)) . Use of specific anti-Kupffer cell- and anti-desmin antibodies, combined with endocytosis of fluorescently labeled macromolecular soluble ligands indicated that the LSEC fraction contained 62 x 107 (sd 12 x 107) purified LSEC . Cultured LSEC avidly endocytosed ligands for the mannose and scavenger receptors . CONCLUSIONS: We show here for the first time that pig LSEC, similar to what has been found earlier in rat LSEC, represent an effective scavenger system for removal of macromolecular waste products from the circulation.

Transpl Infect Dis, 2002 Dec, 4(4), 207 - 11
Disseminated Pseudallescheria boydii (Scedosporium apiospermum) infection in a renal transplant patient; Campagnaro EL et al.; Transplant recipients receive a number of immunosuppressive medications that result in an increased risk of infection, including infections with microbes that are normally not pathogenic . We describe a patient with end-stage renal disease who underwent kidney transplantation . Six months postoperatively, he presented with a lesion on his ankle, multiple thigh nodules, and right testicular pain . Biopsy of the ankle lesion demonstrated Pseudallescheria boydii (Scedosporium apiospermum), a common environmental fungus . Following orchiectomy, multiple fungal elements were found that were initially described as Aspergillus species, but later identified as P . boydii . In addition, multiple brain abscesses were found on magnetic resonance imaging . Despite treatment with multiple antifungal medications, the patient died of cardiac dysrhythmia . Current diagnostic and therapeutic alternatives for P . boydii are reviewed.

Genet Res, 2002 Oct, 80(2), 79 - 87
Male age, host effects and the weak expression or non-expression of cytoplasmic incompatibility in Drosophila strains infected by maternally transmitted Wolbachia; Reynolds KT et al.; In Drosophila melanogaster, the maternally inherited endocellular microbe Wolbachia causes cytoplasmic incompatibility (CI) in crosses between infected males and uninfected females . CI results in a reduction in the number of eggs that hatch . The level of CI expression in this species has been reported as varying from partial (a few eggs fail to hatch) to nonexistent (all eggs hatch) . We show that male age in this host species has a large impact on the level of CI exhibited and explains much of this variability . Strong CI is apparent when young males are used in crosses . CI declines rapidly with male age, particularly when males are repeatedly mated . Wolbachia from a Canton S line that was previously reported as not causing CI does in fact induce CI when young males are used in crosses, albeit at a weaker level than in other D . melanogaster strains . The strain differences in CI expression are due to host background effects rather than differences in Wolbachia strains . These results highlight the importance of undertaking crosses with a range of male ages and nuclear backgrounds before ascribing particular host phenotypes to Wolbachia strains.

J Allergy Clin Immunol, 2003 Jan, 111(1), 24 - 32; quiz 33
Mast cells: beyond IgE; Boyce JA; Mast cells, historically known for their involvement in type I hypersensitivity, also serve critical protective and homeostatic functions . They directly recognize the products of bacterial infection through several surface receptor proteins, releasing proteases, cytokines, and eicosanoid mediators that recruit neutrophils, limit the spread of bacterial infection, and facilitate subsequent tissue repair . In vitro studies suggest that the spectrum of microbes capable of initiating mast cell activation is broad and extends to common respiratory viruses, mycoplasma, and even products of tissue injury, such as nucleotides . TH2-polarized inflammation elicits a reactive hyperplasia of mast cells at the involved mucosal surfaces in both mice and human subject . Several recombinant TH2 cytokines (IL-3, IL-4, IL-5, and IL-9) act synergistically with stem cell factor to facilitate proliferation of nontransformed human mast cells in vitro . IL-4 induces the expression of critical inflammation-associated genes by human mast cells, such as those encoding leukotriene C4 synthase, Fc(epsilon)RI, and several cytokines . Consequently, priming with IL-4 not only amplifies classical Fc(epsilon)RI-dependent mast cell activation but also dramatically alters the product profile of mast cells activated by innate signals and by chemical mediators of inflammation . Strikingly, IL-4 induces an activation response by mast cells to cysteinyl leukotrienes, which act through a receptor shared with uridine diphosphate to induce cytokine generation without exocytosis . It Is possible that alterations in mast cell phenotype by the TH2 milieu of allergy permits otherwise trivial infections or homeostatic chemical signals to initiate harmful inflammatory cascades and sustain tissue pathology . Drug development must take these nonclassical mast cell activation pathways into account without compromising the beneficial and protective functions of mast cells.

Science, 2003 Jan 17, 299(5605), 386 - 8
Ancient tripartite coevolution in the attine ant-microbe symbiosis; Currie CR et al.; The symbiosis between fungus-growing ants and the fungi they cultivate for food has been shaped by 50 million years of coevolution . Phylogenetic analyses indicate that this long coevolutionary history includes a third symbiont lineage: specialized microfungal parasites of the ants' fungus gardens . At ancient levels, the phylogenies of the three symbionts are perfectly congruent, revealing that the ant-microbe symbiosis is the product of tripartite coevolution between the farming ants, their cultivars, and the garden parasites . At recent phylogenetic levels, coevolution has been punctuated by occasional host-switching by the parasite, thus intensifying continuous coadaptation between symbionts in a tripartite arms race.

J Microbiol Methods, 2003 Mar, 52(3), 367 - 77
ATP as a biomarker of viable microorganisms in clean-room facilities; Venkateswaran K et al.; A new firefly luciferase bioluminescence assay method that differentiates free extracellular ATP (dead cells, etc.) from intracellular ATP (viable microbes) was used to determine the viable microbial cleanliness of various clean-room facilities . For comparison, samples were taken from both clean-rooms, where the air was filtered to remove particles >0.5 microm, and ordinary rooms with unfiltered air . The intracellular ATP was determined after enzymatically degrading the sample's free ATP . Also for comparison, cultivable microbial populations were counted on nutrient-rich trypticase soy agar (TSA) plates . Both the cultivable and ATP-based determinations indicate that the microbial burden was lower in clean-room facilities than in ordinary rooms . However, there was no direct correlation between the two sets of measurements because the two assays measured very different populations . A large fraction of the samples yielded no colony formers on TSA, but were positive for intracellular ATP . Subsequently, genomic DNA was isolated directly from selected samples and 16S rDNA fragments were cloned and sequenced, identifying nearest neighbors, many of which are known to be noncultivable in the media employed . It was concluded that viable microbial contamination can be reliably monitored by measurement of intracellular ATP, and that this method may be considered superior to cultivable colony counts due to its speed and its ability to report the presence of viable but noncultivable organisms . When the detection of nonviable microbes is of interest, the ATP assay can be supplemented with DNA analysis.

Sleep Med Rev, 2002 Jun, 6(3), 213 - 27
The significance of saliva during sleep and the relevance of oromotor movements; Thie NM et al.; Saliva is an essential component of the oroesophageal milieu and allows for normal speech, taste, mastication, food bolus formation and swallowing . Saliva has important functions in protecting the hard and soft tissues of the oral cavity from acids and pathogenic microbes . A large number of people suffer either subjective or objective alterations in quantity and/or quality of their saliva that may be secondary to disease, medications, medical treatments or emotional events . Sleep-related xerostomia is a sensation of dry mouth associated with a report of either mouth and/or throat discomfort that induces awakenings for water intake . The prevalence of self-reported dry mouth complaint during sleep (associated with awakening and water intake) in a Canadian survey was estimated at 23% . The biological significance of decreased saliva during sleep is unknown and it is unclear how the oral cavity compensates for this period of relative dryness . The amount of saliva produced is greatest during the waking hours of the day and diminishes dramatically during sleep and may represent another process in the human body that displays a circadian rhythmicity . Salivary secretion during wakefulness is, in part, associated with oromotor activity involving the masticatory muscles . Rhythmic masticatory muscle activity and swallowing are non-disruptive events that occur during normal sleep . We hypothesize herein that lubrication from saliva is necessary during sleep to protect tissue integrity and health of oroesophageal structures.

Paediatr Respir Rev, 2000 Jun, 1(2), 128 - 34
Host defence mechanisms of the respiratory system; Gerritsen J; From the moment of the first breath at the time of birth, the respiratory system must be protected from numerous insults from the environment . The way in which the airways are prepared for these insults is by an extraordinarily effective defence system . This defence system includes mechanical as well as biochemical processes that work in an integrated way to safeguard the lungs . The airways have an efficient, highly vigilant, non-inflammatory anti-microbial defence system, capable of dealing with a wide spectrum of microbes, and provide lifelong protection of these vital mucosal surfaces . The different aspects of this defence system of the airways are discussed . The effectiveness of the system must be improved, especially in children prone to frequent respiratory infections like cystic fibrosis . Future research must be focused on restoring the defect in the defence mechanism, but also in a more appropriate shield against pathogenic micro-organisms.

Adv Space Res, 2002, 30(4), 871 - 6
Investigating the cellular effects of isolated radiation tracks using microbeam techniques; Prise KM et al.; Studies of the effects of radiation at the cellular level have generally been carried out by exposing cells randomly to the charged-particle tracks of a radiation beam . Recently, a number of laboratories have developed techniques for microbeam irradiation of individual cells . These approaches are designed to remove much of the randomness of conventional methods and allow the nature of the targets and pathways involved in a range of radiation effects to be studied with greater selectivity . Another advantage is that the responses of individual cells can be followed in a time-lapse fashion and, for example, processes such as "bystander" effects can be studied clearly . The microbeam approach is of particular importance in mechanistic studies related to the risks associated with exposure to low fluences of charged particles . This is because it is now possible to determine the actions of strictly single particle tracks and thereby mimic, under in vitro conditions, exposures at low radiation dose that are significant for protection levels, especially those involving medium- to high-LET radiations . Overall, microbeam methods provide a new dimension in exploring mechanisms of radiation effect at the cellular level . Microbeam methods and their application to the study of the cellular effects of single charged-particle traversals are described . c2002 COSPAR . Published by Elsevier Science Ltd . All rights reserved.

Plant Physiol, 2003 Jan, 131(1), 215 - 27
Alanine aminotransferase homologs catalyze the glutamate:glyoxylate aminotransferase reaction in peroxisomes of Arabidopsis; Liepman AH et al.; Plant peroxisomal glyoxylate aminotransferases play central roles within the photorespiratory pathway . Genes encoding glyoxylate aminotransferases have been isolated from several animals and microbes, but only recently have plant homologs been identified . Three Arabidopsis homologs of alanine (Ala):glyoxylate aminotransferase 2 (AGT2) contain a putative type 1 peroxisomal targeting signal (PTS1), but the metabolic significance of these AGT2 homologs is unknown . GGT1 and GGT2 are Ala aminotransferase (AlaAT) homologs from Arabidopsis that represent another type of glyoxylate aminotransferase . These proteins are class I aminotransferases, each containing a putative PTS1 . GGT1 and GGT2 are members of a small family of AlaATs in Arabidopsis . When expressed as recombinant proteins in Escherichia coli, GGT1 and GGT2 displayed biochemical characteristics very similar to one another, and to the Arabidopsis protein purified from leaves . Four aminotransferase activities were specifically associated with GGT1 and GGT2, using the substrate pairs glutamate (Glu):glyoxylate, Ala:glyoxylate, Glu:pyruvate, and Ala:2-oxoglutarate . GGT1 and GGT2 may have partially redundant functions; transcripts of both genes were detected in many of the same tissues . Although Glu:glyoxylate aminotransferase (GGT) activity has been observed in several locations in different plants and algae, including the cytoplasm and mitochondria, our subcellular fractionation data indicate that GGT activity was exclusively peroxisomal in Arabidopsis . Thus, glyoxylate aminotransferase reactions in plant peroxisomes appear to be catalyzed by at least two distinct types of aminotransferases: an AGT1 homolog with serine:glyoxylate aminotransferase activity (A.H . Liepman, L.J . Olsen {2001} Plant J 25: 487-498), and a pair of closely related, potentially redundant AlaAT homologs with GGT activity.

Arthritis Rheum, 2003 Jan, 48(1), 97 - 102
Laser-mediated microdissection facilitates analysis of area-specific gene expression in rheumatoid synovium; Judex M et al.; OBJECTIVE: Current approaches to analyzing gene expression in rheumatoid arthritis (RA) synovium are based on RNA isolated either from cultured synovial cells or from synovial biopsy specimens . This strategy does not, in general, allow distinction of specific gene expression between cells originating from different synovial areas, due to potential mixture of expression profiles . Therefore, we established the combination of laser-mediated microdissection (LMM) and differential display to analyze profiles of gene expression in histologically defined areas of rheumatoid synovium . The present study was undertaken to establish parameters for this technique and assess its usefulness for gene expression analysis . METHODS: Cryosections derived from RA synovial tissues were used to obtain cell samples from synovial lining versus sublining, using a microbeam laser microscope . RNA was isolated and analyzed by nested RNA arbitrarily primed-polymerase chain reaction (RAP-PCR) for differential display fingerprinting . Differentially expressed bands were cut out, and PCR products were eluted, cloned, and sequenced . Differential expression of identified sequences was confirmed by in situ hybridization and immunohistochemistry analysis . RESULTS: Microdissected sections of RA synovial tissue containing approximately 600 cells yielded enough RNA to produce a reproducible RNA fingerprint pattern . Several genes could be identified as being expressed differentially between the synovial lining and the sublining, and their expression could be confirmed at the messenger RNA and protein levels . CONCLUSION: The combination of LMM and RAP-PCR presents a valuable tool to obtain novel insights into the area-dependent differential regulation of gene expression in RA synovium . Both known and previously unknown genes were revealed with this technique . This study is the first to demonstrate the potential of this analytic strategy in the investigation of a nonmalignant, multifactorial, inflammatory disease.

Immunol Lett, 2003 Jan 22, 85(2), 153 - 7
Dendritic cells as a tool to combat infectious diseases; Moll H; Dendritic cells (DCs) form a network of potent antigen-presenting cells that initiate and amplify immune responses . The detection and capture of microorganisms by DCs trigger stimulus-specific maturation programs that enable DCs to convey pathogen-associated signals to the adaptive branch of the immune system . The appropriate activation of DCs is critical for their ability to direct the development of either a Th1 or a Th2 response, thereby determining the outcome of microbial infections . Advances in the understanding of DC interactions with microbes provide new concepts for immune interventions . In different models of infectious disease, it has been demonstrated that DCs can serve as vaccine carriers, mediating protection against various types of pathogens . The studies of the requirements of ex vivo manipulations of DCs may lead to the design of vaccines that induce protective immunity to infections by appropriate targeting of DCs in vivo.

Genetics, 2002 Dec, 162(4), 1505 - 11
The rate and character of spontaneous mutation in an RNA virus; Malpica JM et al.; Estimates of spontaneous mutation rates for RNA viruses are few and uncertain, most notably due to their dependence on tiny mutation reporter sequences that may not well represent the whole genome . We report here an estimate of the spontaneous mutation rate of tobacco mosaic virus using an 804-base cognate mutational target, the viral MP gene that encodes the movement protein (MP) . Selection against newly arising mutants was countered by providing MP function from a transgene . The estimated genomic mutation rate was on the lower side of the range previously estimated for lytic animal riboviruses . We also present the first unbiased riboviral mutational spectrum . The proportion of base substitutions is the same as that in a retrovirus but is lower than that in most DNA-based organisms . Although the MP mutant frequency was 0.02-0.05, 35% of the sequenced mutants contained two or more mutations . Therefore, the mutation process in populations of TMV and perhaps of riboviruses generally differs profoundly from that in populations of DNA-based microbes and may be strongly influenced by a subpopulation of mutator polymerases.

Environ Sci Technol, 2002 Dec 15, 36(24), 5483 - 90
Influence of heterotrophic microbial growth on biological oxidation of pyrite; Marchand EA et al.; The rate and extent of pyrite oxidation by the iron-oxidizing bacteria Acidithiobacillus ferrooxidans was limited by the growth of the heterotrophic microbe Acidiphilium acidophilum . In batch systems containing a mixture of both organisms, the maximum zero-order rate of ferric iron accumulation was about 1.4 mg of Fe3+ L(-1) d(-1) as compared to 9.4 mg of Fe3+ L(-1) d(-1) for pure cultures of A . ferrooxidans under the same conditions . Pyrite oxidation was limited in cases where both cultures of organisms were initially present as well as situations where the heterotrophic organisms were added to established, pyrite-oxidizing systems containing A . ferrooxidans . Results also indicated that organic carbon remaining in solution following heterotrophic bacterial growth reduced the rate of abiotic pyrite oxidation by the ferric ion . Furthermore, a cell-free solution of the residual organic carbon resulted in a lag of A . ferrooxidans growth in soluble ferrous medium . The residual organic carbon solution that accumulated during the growth of Aph . acidophilum had a diverse molecular weight distribution, indicating that different compounds could be responsible for the inhibition of chemical pyrite oxidation and the A . ferrooxidans growth lag observed . Titration of dissolved copper ions with residual dissolved organic carbon originating from Aph . acidophilum cultures indicated that a metal complexation mechanism could be responsible for the lower rates of pyrite oxidation observed . These data suggest that encouraging the growth of heterotrophic microorganisms under acid mine drainage conditions may be a feasible strategy for decreasing both the rate and the extent of sulfide mineral oxidation.

Nucleic Acids Res, 2003 Jan 1, 31(1), 365 - 70
The SWISS-PROT protein knowledgebase and its supplement TrEMBL in 2003; Boeckmann B et al.; The SWISS-PROT protein knowledgebase connects amino acid sequences with the current knowledge in the Life Sciences . Each protein entry provides an interdisciplinary overview of relevant information by bringing together experimental results, computed features and sometimes even contradictory conclusions . Detailed expertise that goes beyond the scope of SWISS-PROT is made available via direct links to specialised databases . SWISS-PROT provides annotated entries for all species, but concentrates on the annotation of entries from human (the HPI project) and other model organisms to ensure the presence of high quality annotation for representative members of all protein families . Part of the annotation can be transferred to other family members, as is already done for microbes by the High-quality Automated and Manual Annotation of microbial Proteomes (HAMAP) project . Protein families and groups of proteins are regularly reviewed to keep up with current scientific findings . Complementarily, TrEMBL strives to comprise all protein sequences that are not yet represented in SWISS-PROT, by incorporating a perpetually increasing level of mostly automated annotation . Researchers are welcome to contribute their knowledge to the scientific community by submitting relevant findings to SWISS-PROT at swiss-prot@expasy.org.

Z Gastroenterol, 2002 Dec, 40(12), 983 - 90
"For whom the bell tolls!" -- innate defense mechanisms and survival strategies of the intestinal epithelium against lumenal pathogens; Cario E et al.; The intestinal epithelium serves as an essential defensive barrier of the mucosal immune system that forms a bipolar interface between the diverse populations of microbes of the lumen and subjacent immune cells present in the lamina propria . Intestinal epithelial cells express various pattern recognition receptors -- poised to recognize microbial "pathogen-associated molecular patterns" as "non-self" and to rapidly initiate innate immune responses of survival and active defense strategies against lumenal pathogens . Current understanding of the variety of innate immune features present in intestinal epithelium to maintain homeostasis is summarized and the mechanisms through which dysregulation may play a central role in initiation and perpetuation of inflammatory bowel disease are discussed.

J Immunol, 2003 Jan 15, 170(2), 997 - 1001
Identification of IFN regulatory factor-1 binding site in IL-12 p40 gene promoter; Maruyama S et al.; IL-12 is a heterodimer composed of p40 and p35 and is a key cytokine that functions to protect the host from viral and microbial infections . IL-12 links the innate immune system with the acquired immune system during infection, and induces differentiation of type 1 T cells that play an important role in the eradication of microbes . The induction of the IL-12 p40 gene is regulated by NF-kappaB in the presence of IFN-gamma . IFN-gamma induces IFN regulatory factor-1 (IRF-1), which in turn induces the transcription of the IL-12 p40 gene . However, the IRF-1 binding site in the promoter region of the IL-12 p40 gene has not yet been formally determined . In the present study, we demonstrated that IRF-1 directly binds to the IL-12 p40 gene promoter and identified its binding site . The IRF-1 binding site in the promoter region of the IL-12 p40 gene is shown to be in the -72 to -58 area of the 5'-upstream region . The -63 to -61 position is the critical site within this region for the binding of IRF-1 to the IL-12 p40 gene promoter . While IFN-gamma must be present for IL-12 p40 gene induction, the p35 gene is strongly induced by LPS, even in the absence of IFN-gamma, and therefore the induction of the p35 gene is IRF-1 independent.

Appl Environ Microbiol, 2003 Jan, 69(1), 49 - 55
Recombinant environmental libraries provide access to microbial diversity for drug discovery from natural products; Courtois S et al.; To further explore possible avenues for accessing microbial biodiversity for drug discovery from natural products, we constructed and screened a 5,000-clone "shotgun" environmental DNA library by using an Escherichia coli-Streptomyces lividans shuttle cosmid vector and DNA inserts from microbes derived directly (without cultivation) from soil . The library was analyzed by several means to assess diversity, genetic content, and expression of heterologous genes in both expression hosts . We found that the phylogenetic content of the DNA library was extremely diverse, representing mostly microorganisms that have not been described previously . The library was screened by PCR for sequences similar to parts of type I polyketide synthase genes and tested for the expression of new molecules by screening of live colonies and cell extracts . The results revealed new polyketide synthase genes in at least eight clones . In addition, at least five additional clones were confirmed by high-pressure liquid chromatography analysis and/or biological activity to produce heterologous molecules . These data reinforce the idea that exploiting previously unknown or uncultivated microorganisms for the discovery of novel natural products has potential value and, most importantly, suggest a strategy for developing this technology into a realistic and effective drug discovery tool.

DNA Repair (Amst), 2002 Aug 6, 1(8), 579 - 600
Arabidopsis thaliana, a versatile model system for study of eukaryotic genome-maintenance functions; Hays JB; The genome of the model plant Arabidopsis thaliana encodes many orthologs of human genome-maintenance proteins, and in several important cases plant DNA repair and mutation-antagonism functions resemble their mammalian counterparts more closely than do those of established microbial models . These orthologs, in conjunction with the powerful tools now available for work with Arabidopsis and the practical advantages of its small size and rapid life cycle, now make it an attractive model system for study of eukaryotic DNA repair and mutagenesis . Already, null mutations that inactivate proteins involved in repair of DNA double-strand breaks or in DNA translesion synthesis and are lethal in mice have proved to be tolerated by plants . This review compares in some detail the genome-maintenance activities encoded by plants, mammals and microbes, and describes important Arabidopsis tools and life cycle characteristics . It concludes with selected examples that illustrate Arabidopsis advantages and/or reveal new insights into genome-maintenance functions of general interest.

Pediatr Res, 2003 Jan, 53(1), 137 - 42
The conserved TFLK motif of mammary-associated serum amyloid A3 is responsible for up-regulation of intestinal MUC3 mucin expression in vitro; Mack DR et al.; In various mammalian species, an isoform of serum amyloid A is secreted at high concentrations into colostrum . A conserved four-amino-acid motif (TFLK) is contained within the first eight N-terminal amino acid residues of this mammary-associated serum amyloid A isoform 3 (M-SAA3) . Peptides derived from the bovine N-terminal amino acid sequence of M-SAA3 were produced and added to cell culture medium of HT29 cells to study the effects on intestinal mucin gene expression . HT29 cells were grown to enhance expression of either MUC2 or MUC3 intestinal mucins . After incubation, total RNA was isolated for Northern blot analyses using MUC2 or MUC3 mucin cDNA probes . Signals were detected by autoradiography with mRNA levels expressed relative to 28S rRNA . The 10-mer peptides containing the intact TFLK-motif or a TFLK 4-mer peptide increased MUC3 mRNA expression compared with control cells (p < 0.05) . There was no effect of these peptides on MUC2 mRNA expression . Cells that were incubated with 10-mer N-terminal derived peptides containing a scrambled TFLK motif, with all 10 amino acid residues scrambled or derived from a C-terminal region of M-SAA3, did not show increased MUC3 expression . Inhibition of enteropathogenic Escherichia coli strain E2348/69 adhesion to HT29 cells grown to enhance MUC3 expression was reduced by a similar amount when either peptides containing the intact TFLK motif or probiotic microbes were added to cell culture medium compared with control cells . M-SAA3 is a bioactive peptide secreted into colostrums that can up-regulate mucin expression and thereby may enhance innate protective mechanisms that limit access of deleterious microbes to intestinal mucosal epithelial cells in the postparturition period.

EMBO J, 2003 Jan 2, 22(1), 24 - 35
Directed evolution of an extremely fast phosphotriesterase by in vitro compartmentalization; Griffiths AD et al.; We describe the selection of a phosphotriesterase with a very fast k(cat) (over 10(5) s(-1)), 63 times higher than the already very efficient wild-type enzyme . The enzyme was selected from a library of 3.4 x 10(7) mutated phosphotriesterase genes using a novel strategy based on linking genotype and phenotype by in vitro compartmentalization (IVC) using water-in-oil emulsions . First, microbeads, each displaying a single gene and multiple copies of the encoded protein, are formed by compartmentalized in vitro translation . These microbeads can then be selected for catalysis or binding . To select for catalysis the microbeads are re-emulsified in a reaction buffer of choice with a soluble substrate . The product and any unreacted substrate are coupled to the beads when the reaction is finished . Product-coated beads, displaying active enzymes and the genes that encode them, are detected with anti-product antibodies and selected using flow cytometry . This completely in vitro process selects for all enzymatic features simultaneously (substrate recognition, product formation, rate acceleration and turnover) and single enzyme molecules can be detected.

Toxicology, 2002 Dec 27, 181-182, 323 - 8
Influences on the development of allergy and asthma; Peden DB; A number of factors contribute to development of asthma and allergy in humans . Genetic factors clearly play a role in development of asthma and allergy . However, recent studies suggest that westernized lifestyle, perhaps certain pollutants, and less frequent exposure to microbes may allow for allergy to develop . It is the interactions of risk genes with urbanized environments that lead to development of allergy . Recent studies suggest that the most significant period of development of allergy is in early childhood, with additional data suggesting that a tendency for mononuclear cells to produce Th2 cytokines exists in early childhood . Reviewed in this article are genetic, inflammatory and lifestyle factors which contribute to development of allergy in childhood.

J Gen Appl Microbiol, 1999 Oct, 45(5), 221 - 227
Quinone profiles in lake sediments: Implications for microbial diversity and community structures; Hiraishi A et al.; Microbial quinone compositions of sediment mud samples from five different lakes in Japan were studied by spectrochromatography and mass spectrometry . The total quinone content of these samples ranged from 1.97 to 18.0 nmol/g dry weight of sediment, of which a combined fraction of ubiquinones and menaquinones accounted for 42 to 74% . The remaining fraction (26 to 58%) consisted of the photosynthetic quinones, plastoquinones and phylloquinone . The sediment samples produced PQ-9 or Q-8 as the most abundant quinone type regardless of their geographic locations and depths . These results indicate that oxygenic phototrophic microorganisms and Q-8-containing proteobacteria constituted major parts of microbial populations in the lake sediment . In the surface water of the same sampling sites, plastoquinones and phylloquinone occurred in much higher proportions . These findings suggested that the high abundance of oxygenic phototrophs in the sediment muds resulted from their constant movement or sedimentation from the surface water . Numerical analyses of the quinone profiles showed that the microbial communities of the sediment were diverse and different in different lakes but similar to each other in the diversity of bioenergetic modes . Three physiological groups of microbes showing ubiquinone-mediated aerobic respiration, oxygenic photosynthesis, and menaquinone-associated respiration were suggested to inhabit the lake sediments in balance.

Bioinformatics, 2003 Jan, 19(1), 153 - 4
An integrated genetic data environment (GDE)-based LINUX interface for analysis of HIV-1 and other microbial sequences; De Oliveira T et al.; MOTIVATION: Sequence databases encode a wealth of information needed to develop improved vaccination and treatment strategies for the control of HIV and other important pathogens . To facilitate effective utilization of these datasets, we developed a user-friendly GDE-based LINUX interface that reduces input/output file formatting . DESIGN AND RESULTS: GDE was adapted to the Linux operating system, bioinformatics tools were integrated with microbe-specific databases, and up-to-date GDE menus were developed for several clinically important viral, bacterial and parasitic genomes . Each microbial interface was designed for local access and contains Genbank, BLAST-formatted and phylogenetic databases . AVAILABILITY: GDE-Linux is available for research purposes by direct application to the corresponding author . Application-specific menus and support files can be downloaded from .

Chromosome Res, 2002, 10(7), 571 - 7
The use of laser microdissection for the preparation of chromosome-specific painting probes in farm animals; Kubickova S et al.; Laser microbeam microdissection and laser pressure catapulting procedure were used for the construction of chromosome-specific painting probes, arm-specific probes and probes for chromosomal subfragments . We report on a method for generation of fluorescence in-situ hybridization probes from laser dissected chromosomes of farm animals . So far, using the described method, a set of chromosome-specific painting probes has been obtained for all porcine chromosomes, 17 chromosomes of cattle and selected equine chromosomes . It is concluded that the laser technology appears to be a useful and powerful tool for the construction of chromosome-specifi c painting probes . Its main advantage is the fast non-contact collection of chromosomes.

Infect Immun, 2003 Jan, 71(1), 47 - 60
Diversity at the locus associated with transcription of a variable surface antigen of Pneumocystis carinii as an index of population structure and dynamics in infected rats; Keely SP et al.; Pneumocystis carinii expresses a surface glycoprotein called MSG . Different isoforms of MSG are encoded by a gene family spread over at least 15 telomeric sites . Only one locus, called UCS, supports the production of MSG mRNA . Previous studies showed that P . carinii populations from individual rats exhibited high degrees of diversity with respect to the MSG genes attached to the UCS locus . This diversity could have been generated primarily in the rats studied . Alternatively, the rats may have been infected by P . carinii organisms that were already different at the UCS locus . To investigate this issue, we examined the UCS locus in P . carinii from rats that had been exposed to few of the microbes at a specified time, which produced a bottleneck in the microbial population . Some of the rats with bottlenecks produced P . carinii populations in which a single MSG sequence resided at the UCS locus in 80 to 90% of the organisms, showing that P . carinii can proliferate within a rat without generating the very high levels of UCS diversity previously seen . From the degree of diversity observed in the bottlenecked populations, the maximum rate of switching appeared to be 0.01 event per generation . These data also suggest that the infectious dose is as low as one organism, that rats that share a cage readily infect each other, and that the doubling time of P . carinii in vivo is approximately 3 days . In addition, we found that inoculation with 10(7) P . carinii organisms from a population highly heterogeneous at the UCS locus reproduced this heterogeneity . By contrast, shifts in population structure occurred in rats given 10(4) P . carinii organisms, suggesting that a small fraction of these proliferated.

Semin Pediatr Infect Dis, 2002 Oct, 13(4), 273 - 9
Legionella pneumophila pathogenesis and immunity; Friedman H et al.; Legionella pneumophila is a ubiquitous intracellular bacterium found widely in the environment and is the cause of sporadic outbursts of opportunistic infection, mainly in immunocompromised individuals, including young children as well as aged persons . The host response to this organism is similar to responses to other opportunistic intracellular microbes and features both innate and adoptive immune mechanisms . Innate immunity includes the responses of a variety of host cells and cytokines, including those produced by macrophages stimulated by microbial antigens . Adoptive immunity consists of activated lymphocytes and the cytokines they produce, such as interferon and other cytokines that activate macrophages to restrict the growth and spread of intracellular bacteria . The role of cytokines specifically in resistance and immunity to Legionella is exemplified by studies concerning the nature and mechanism whereby interferon produced by activated T lymphocytes influences macrophages to resist infection by this bacterium, not only by restricting growth but also killing this bacterium . This cytokine is considered to have a key role in activating macrophages in adoptive immunity to Legionella and other intracellular bacteria . In particular, interferon is known to have a crucial role in activating macrophages to resist infection by L . pneumophila . This review also describes newer findings that demonstrate that various cytokines that define Th1 vs Th2 helper cell activity also are important in regulating resistance versus susceptibility to this ubiquitous microorganism .

Am J Physiol Cell Physiol, 2003 Apr, 284(4), C1048 - 53 Epub 2002 Dec 18.
Oxidative stress-induced cell death of human oral neutrophils; Sato EF et al.; Polymorphonuclear leukocytes (PMN) play crucial roles in protecting hosts against invading microbes and in the pathogenesis of inflammatory tissue injury . Although PMN migrate into mucosal layers of digestive and respiratory tracts, only limited information is available of their fate and function in situ . We previously reported that, unlike circulating PMN (CPMN), PMN in the oral cavity spontaneously generate superoxide radical and nitric oxide (NO) in the absence of any stimuli . When cultured for 12 h under physiological conditions, oral PMN (OPMN) showed morphological changes that are characteristic of those of apoptosis . Upon agarose gel electrophoresis, nuclear DNA samples isolated from OPMN revealed ladder-like profiles characteristic of nucleosomal fragmentation . l-cysteine, reduced glutathione (GSH), and herbimycin A, a protein tyrosine kinase inhibitor, suppressed the activation of caspase-3 and apoptosis of OPMN . Neither thiourea, superoxide dismutase (SOD), nor catalase inhibited the activation of caspase-3 and apoptosis . Moreover, N-acetyl-Asp-Glu-Val-Asp-aldehyde (Ac-DEVD-CHO), inhibitor for caspase-3, inhibited the fragmentation of DNA . These results suggested that oxidative stress and/or tyrosine-kinase-dependent pathway(s) activated caspase-3 in OPMN, thereby inducing their apoptosis.

J Leukoc Biol, 2002 Dec, 72(6), 1172 - 9
Immune complex stimulation of human neutrophils involves a novel Ca2+/H+ exchanger that participates in the regulation of cytoplasmic pH: flow cytometric analysis of Ca2+/pH responses by subpopulations; Bernardo J et al.; The activation of human phagocytic leukocytes by immune complexes (IC) or opsonized microbes via their Fc and complement receptors has been well-described . The mechanisms involved in this process are complex and depend on the receptors involved . The biochemical events that lead to the destruction of invading organisms in turn display varying degrees of interdependence, but the controlling elements that lead to the ultimate killing of ingested organisms within phagosomes by lysosomal enzymes and reactive oxygen intermediates are still not completely understood . We have addressed these mechanisms by following and correlating the kinetics of responses by individual cells, using multiparameter flow cytometry . Using nonopsonized IC as stimuli, we document here the presence of a novel Ca(2)(+)/H(+) voltage-independent channel in human neutrophils, which helps to control their cytoplasmic pH.

Biophys Chem, 2002 Dec 10, 101-102, 387 - 99
Metabolism of pyrrolizidine alkaloids by Peptostreptococcus heliotrinreducens and a mixed culture derived from ovine ruminal fluid; Hovermale JT et al.; A mixed culture of ovine ruminal microbes metabolizes the macrocyclic pyrrolizidine alkaloids present in the plant Senecio jacobaea, including jacobine and seneciphylline . Previous attempts to identify metabolites of these alkaloids have not been successful . The objective of this study was to compare the metabolism of pyrrolizidine alkaloids by a mixed culture of ovine ruminal microbes to the metabolism of pyrrolizidine alkaloids by the known organism Peptostreptococcus heliotrinreducens . P . heliotrinreducens metabolizes the pyrrolizidine alkaloids heliotrine and lasiocarpine to 7alpha-hydroxy-1-methylene-8alpha-pyrrolizidine and 7alpha-angelyl-1-methylene-8alpha-pyrrolizidine, respectively . This organism does not metabolize the pyrrolizidine alkaloids jacobine or seneciphylline . A mixed culture of ovine ruminal microbes also metabolized heliotrine and lasiocarpine to identical methylene compounds . This mixed culture also metabolized jacobine and seneciphylline, with the production of very low levels of the corresponding 1-methylene compounds . Samples were analyzed by TLC and GC/MS .

Crit Rev Biotechnol, 2002, 22(4), 315 - 33
Rainforest endophytes and bioactive products; Strobel GA; An increase in the number of people in the world having health problems caused by certain cancers, drug-resistant bacteria, parasitic protozoans, and fungi has caused alarm . An intensive search for newer and more effective agents to deal with these problems is now underway . Endophytes are a potential source of novel chemistry and biology to assist in helping solve not only human health, but plant and animal health problems also . Endophytes reside in the tissues between living plant cells . The relationship that they establish with the plant varies from symbiotic to bordering on pathogenic . Of all of the world's plants, it seems that only a few grass species have had their complete complement of endophytes studied . As a result, the opportunity to find new and interesting endophytes among the myriad of plants is great . Sometimes extremely unusual and valuable organic substances are produced by these endophytes . These compounds may contribute to the host-microbe relationship . The initial step in dealing with endophytic microorganisms is their successful isolation from plant materials . Then, the isolation and characterization of bioactive substances from culture filtrates is done using bioassay guided fractionation and spectroscopic methods . Some of the more interesting compounds produced by endophytic microbes with which we have dealt are taxol, cryptocin, cryptocandin, jesterone, oocydin, isopestacin, the pseudomycins and ambuic acid . This review discusses an approach for bio-prospecting the rainforests, not only to harvest their endophytic microorganisms, but to eventually build a better understanding of the importance and value they have to humankind.

Arthritis Rheum, 2002 Dec, 46(12), 3349 - 60
Isolation and characterization of bone marrow multipotential mesenchymal progenitor cells; Jones EA et al.; OBJECTIVE: There is an increased interest in rheumatology in mesenchymal progenitor/stem cells (MPCs) and their roles in rheumatic diseases, but little is known about the phenotype of these cells in vivo . The aim of this study was to isolate and characterize human bone marrow (BM) MPCs . METHODS: Fluorescence microscopy was used to identify putative MPCs among adherent BM cells . To purify them, a positive selection with antifibroblast microbeads was used, combined with fluorescence-activated cell sorting (FACS) for microbead+,CD45(low) cells . A more detailed phenotype of these cells was determined using 4-color flow cytometry, and standard chondrogenic, osteogenic, and adipogenic assays were used to investigate their differentiation potentials . RESULTS: Putative MPCs microscopically identified as large, fibroblast-like, D7-FIB+ cells were purified using positive selection with D7-FIB-conjugated (antifibroblast) microbeads followed by FACS for specifically bound microbead+,CD45(low) cells . These cells represented 0.01% of mononuclear cells in the BM . They were uniformly positive for CD105, LNGFR, HLA-DR, CD10, CD13, CD90, STRO-1, and bone morphogenetic protein receptor type IA (BMPRIA) and were negative for CD14, CD34, CD117, and CD133 . Only cells with this phenotype could proliferate and produce adherent cell monolayers capable of chondrogenic, osteogenic, and adipogenic differentiation . D7-FIB- cells in the BM lacked any MPC activity . Uncultured skin fibroblasts had a phenotype similar to that of BM MPCs, but were negative for LNGFR, STRO-1, HLA-DR, and BMPRIA . CONCLUSION: This study shows the distinct phenotype, morphology, and method of isolation of BM MPCs . The findings may have implications for defining the physiologic roles of MPCs in arthritis, bone diseases, and joint regeneration.

Dev Biol, 2002 Dec 15, 252(2), 188 - 201
A novel invertebrate trophic factor related to invertebrate neurotrophins is involved in planarian body regional survival and asexual reproduction; Bueno D et al.; Trophic factors are a heterogeneous group of molecules that promote cell growth and survival . In freshwater planarians, the small secreted protein TCEN49 is linked to the regional maintenance of the planarian central body region . To investigate its function in vivo, we performed loss-of-function and gain-of-function experiments by RNA interference and by the implantation of microbeads soaked in TCEN49, respectively . We show that TCEN49 behaves as a trophic factor involved in central body region neuron survival . In planarian tail regenerates, tcen49 expression inhibition by double-stranded RNA interference causes extensive apoptosis in various cell types, including nerve cells . This phenotype is rescued by the implantation of microbeads soaked in TCEN49 after RNA interference . On the other hand, in organisms committed to asexual reproduction, both tcen49 mRNA and its protein are detected not only in the central body region but also in the posterior region, expanding from cells close to the ventral nerve chords . In some cases, the implantation of microbeads soaked in TCEN49 in the posterior body region drives organisms to reproduce asexually, and the inhibition of tcen49 expression obstructs this process, suggesting a link between the central nervous system, TCEN49, regional induction, and asexual reproduction . Finally, the distribution of TCEN49 cysteine and tyrosine residues also points to a common evolutionary origin for TCEN49 and molluscan neurotrophins.

FEBS Lett, 2002 Dec 18, 532(3), 455 - 8
Microbead display by in vitro compartmentalisation: selection for binding using flow cytometry; Sepp A et al.; In vitro compartmentalisation in an emulsion was used to physically link proteins to the DNA that encodes them via microbeads . These microbeads can be selected for catalysis, or, as demonstrated here, for binding . Genes encoding a peptide containing an epitope (haemagglutinin) were enriched to near purity from a 10(6)-fold excess of genes encoding a different peptide by two rounds of selection using flow cytometry, indicating approximately 1000-fold enrichment per round . Single beads can be isolated using flow sorting and the single gene on the bead amplified by polymerase chain reaction . Hence, the entire process can be performed completely in vitro.

Cryobiology, 2002 Oct, 45(2), 118 - 26
Characterization of cryopreserved human Langerhans cells; Seo KI et al.; Epidermal Langerhans cells are potent antigen-presenting cells in the epidermis . The establishment of a cryopreservation method for human Langerhans cells would greatly contribute to our ability to successfully conduct various experiments dealing with Langerhans cells . Since Langerhans cells are known to be sensitive to cold injury, there have been no reports concerning the cryopreservation of Langerhans cells . We have investigated the effect of cryopreservation on the function and phenotype of human Langerhans cells . Langerhans cells from human foreskins were isolated with the immunomagnetic microbead method using monoclonal antibodies for CD1a . Langerhans cells were cryopreserved in the presence of dimethylsulfoxide (DMSO) 10% and fetal calf serum 90% . Cryopreserved Langerhans cells were phenotypically assessed by flowcytometry using monoclonal antibodies to HLA-DR and CD1a . The ultrastructures of the Langerhans cells were compared using electron microscopy . An autologous T cell stimulation test was performed to compare the functions of cryopreserved Langerhans cells and fresh Langerhans cells . The viability of the cryopreserved Langerhans cells was able to be maintained at more than 90% . Cryopreserved Langerhans cells expressed high levels of HLA-DR and CD1a antigens and stimulated autologous T cells to an extent almost identical to that obtained from fresh Langerhans cells . These findings indicate that the cryopreservation of human Langerhans cells could lead to a breakthrough in various experiments dealing with human Langerhans cells.

Zhonghua Xue Ye Xue Za Zhi, 2002 Nov, 23(11), 568 - 70
{Ex vivo expansion of CD34(+) CD59(+) cells from bone marrow of paroxysmal nocturnal hemoglobinuria patients}; Xiao J et al.; OBJECTIVE: To study the separation, purification and ex vivo expansion of CD(34)(+) CD(59)(+) cells from patients with paroxysmal nocturnal hemoglobinuria (PNH), and explore the new treatment for the PNH patients . METHODS: CD(34)(+) CD(59)(+) cells were selected from the bone marrow mononuclear cells of PNH patients by means of immunomagnetic microbead-flow cytometry two step sorting method, followed by ex vivo expansion of the cells with combination of hematopoietic factors for two weeks . RESULTS: The best combination for the ex vivo expansion was SCF + IL-3 + IL-6 + FL + Tpo + Epo, and the seventh day was the most suitable time for the best harvest when the CD(34)(+) CD(59)(+) cells were 22.42 +/- 3.73 fold expanded . After ex vivo expansion, the cells remained CD(59) positive and potent capacity of colony formation, but their potentialities to multilineage differentiation were decreased . CONCLUSION: The present study shows that ex vivo expansion of CD(34)(+) CD(59)(+) cells from PNH patients might promise the possibility of performing ABMT or APBSCT clinincally for the patients.

Trends Biotechnol, 2003 Jan, 21(1), 38 - 44
Biomineralization of metal-containing ores and concentrates; Rawlings DE et al.; Biomining is the use of microorganisms to extract metals from sulfide and/or iron-containing ores and mineral concentrates . The iron and sulfide is microbially oxidized to produce ferric iron and sulfuric acid, and these chemicals convert the insoluble sulfides of metals such as copper, nickel and zinc to soluble metal sulfates that can be readily recovered from solution . Although gold is inert to microbial action, microbes can be used to recover gold from certain types of minerals because as they oxidize the ore, they open its structure, thereby allowing gold-solubilizing chemicals such as cyanide to penetrate the mineral . Here, we review a strongly growing microbially-based metal extraction industry, which uses either rapid stirred-tank or slower irrigation technology to recover metals from an increasing range of minerals using a diversity of microbes that grow at a variety of temperatures.

Hum Immunol, 2002 Dec, 63(12), 1120 - 5
Roles of toll-like receptors in natural interferon-producing cells as sensors in immune surveillance; Ito T et al.; Natural IFN-alpha/beta producing cells (IPCs) play a central role in innate immunity against microbial infections . In primary immune responses, toll-like receptors (TLRs), as major pattern-recognition receptors, are essential for IPCs as well as other antigen presenting cell (APC) subsets to recognize microbes . IPCs unequivocally express TLR7 and TLR9, and can respond to the respective ligand to produce IFN-alpha/beta and to rapidly differentiate into dendritic cells (DCs) . Thereby, IPCs can not only activate innate immune system but also provoke T cell responses . Thus, IPCs link innate and adaptive immunity through TLR system . In addition, recent work has revealed the regulatory system of DC subsets in response to microbial invasion . In this context, by the different but complementary expression profile of TLRs, IPCs together with myeloid APC subsets constitute a rational system of immune surveillance that can cover a wide variety of pathogens and enlarge immune adjuvant effects.

Pest Manag Sci, 2002 Dec, 58(12), 1259 - 65
Persistence and leaching of beta-cyfluthrin in alluvial soil of India; Gupta S et al.; Persistence as affected by rate of application and moisture regimes and leaching of beta-cyfluthrin was studied in alluvial soil under laboratory conditions . The effects of rate of application and moisture regimes on persistence were studied by incubating fortified soil at 0.1, 1.0 and 10.0 mg kg(-1) under air-dry, field capacity and submerged moisture regimes . The initial deposits of 0.09, 1.11 and 10.1 mg kg(-1) dissipated with time and 78.4-100% loss was recorded at 90 days . The half-life values varied from 7.8 to 41.8 days . The rate of dissipation decreased as the rate of application increased under field capacity and submerged conditions . However, under air-dry conditions, the effect was less pronounced, and half-life values showed a reverse trend . Persistence of beta-cyfluthrin under different moisture regimes followed the trend: air-dry > field capacity > submerged . The trend could be attributed to the effect of moisture on number and type of microbes . Leaching was studied in a packed soil column under saturated flow conditions . beta-Cyfluthrin was found to be highly immobile in alluvial soil . No residues were detected in any leachate fraction under the experimental conditions . In column soil, residues were detected at 0-10 cm depth and the major amount (>99%) was recovered from 0-5 cm depth . Although beta-cyfluthrin showed moderate persistence in alluvial soil, the possibility of its leaching to ground water is negligible as a result of its immobility.

J Neurovirol, 2002 Dec, 8(6), 480 - 5
Autoimmunity as the body's defense mechanism against the enemy within: Development of therapeutic vaccines for neurodegenerative disorders; Schwartz M; Insults to the central nervous system (CNS), whether of microbial or microbe-free origin, result in tissue damage . Until recently, it was generally believed that only microbe-related damage elicits an adaptive immune response, the purpose of which is to eliminate the offending microorganisms . Recent studies in the author's laboratory suggest, however, that the body exhibits an adaptive immune response to microbe-free injuries as well . The immune response in this case is directed against dominant self-antigens residing in the damaged site, where such an adaptive anti-self immune response reinforces the protective activity of local resident cells by providing them with factors that can augment and regulate their capacity for buffering troublemakers such as destructive self-compounds emerging from the injured neural tissue . Because the specificity of this autoimmune response apparently depends not on the type but on the site of lesion, the response can be boosted by therapeutic vaccination for acute and chronic neurodegenerative conditions irrespective of their primary etiology . The results have far-reaching implications, both for microbial infections and for neurodegenerative diseases of the CNS.

J Neurovirol, 2002 Dec, 8(6), 474 - 9
Neural immunity: Friend or foe?
Gendelman HE.
The articles compiled in this special edition of Journal of NeuroVirology target a developing field of investigation seeking to uncover how the immune system affects both the pathogenic process and protection against the ravages of neurodegenerative processes . Whether caused by a microbe, trauma, toxic metabolite, autoimmunity, or part of a wide degenerative process, immune dysfunction commonly affects central nervous system (CNS) disease . All together, the work presented here proved to be a unique undertaking with contributing scientists outside the field of neurovirology . Indeed, multiple disciplines including molecular neuroscience, neuroimmunology, virology, cellular immunology, receptor pharmacology, neuronal electrophysiology, neurochemistry, clinical neurology, and development neurobiology were joined . The basis of this work rests with the hypothesis that brain mononuclear phagocytes (MP; perivascular and brain macrophages and microglia) act as inducers of disease by engaging the immune system to protect, defend, or induce neural injury . Indeed, it is the brain MP that act as scavengers killing microblial pathogens, regulate immune responses through antigen presentation and mobilization of adaptive immune activities, and affect the production of neurotrophic or toxic secretory factors that incite disease processes . For many years, these responses were thought to be reactive to ongoing disease mechanisms with little effects on disease itself, let alone repair . The works compiled in this issue demonstrate quite clearly this is no longer true . Immune responses cannot be directed only against a microbe but also against self-antigens that are expressed in damaged CNS, leading to innate neurotoxic or adaptive anti-self immunity that commonly follow viral infections . Importantly, therapeutic modalities may take advantage of CNS immune responses through vaccination generating neuroprotection . Together, these articles serve to bring together common neuroimmune links between highly divergent diseases (for example, Parkinson's and Alzheimer's disease and human immunodeficiency virus type-one dementia) . In the end, I hope this work will serve as discussion points for future collaborations and began to break down the barriers of disease, enabling targeted research activities toward what we have in common.

Phytochemistry, 2003 Jan, 62(1), 1 - 4
Saponins in cereals; Osbourn AE; Saponins are a diverse family of secondary metabolites that are produced by many plant species, particularly dicots . These molecules commonly have potent antifungal activity and their natural role in plants is likely to be in protection against attack by pathogenic microbes . They also have a variety of commercial applications including use as drugs and medicines . The enzymes, genes and biochemical pathways involved in the synthesis of these complex molecules are largely uncharacterized for any plant species . Cereals and grasses appear to be generally deficient in saponins with the exception of oats, which produce both steroidal and triterpenoid saponins . The isolation of genes for saponin biosynthesis from oats is now providing tools for the analysis of the evolution and regulation of saponin biosynthesis in monocots . These genes may also have potential for the development of improved disease resistance in cultivated cereals.

Biotechnol Bioeng, 2003 Feb 5, 81(3), 348 - 55
Improved fuel cell and electrode designs for producing electricity from microbial degradation; Park DH et al.; A new one-compartment fuel cell was composed of a rubber bunged bottle with a center-inserted anode and a window-mounted cathode containing an internal, proton-permeable porcelain layer . This fuel cell design was less expensive and more practical than the conventional two-compartment system, which requires aeration and a ferricyanide solution in the cathode compartment . Three new electrodes containing bound electron mediators including a Mn(4+)-graphite anode, a neutral red (NR) covalently linked woven graphite anode, and an Fe(3+)-graphite cathode were developed that greatly enhanced electrical energy production (i.e., microbial electron transfer) over conventional graphite electrodes . The potentials of these electrodes measured by cyclic voltametry at pH 7.0 were (in volts): +0.493 (Fe(3+)-graphite); +0.15 (Mn(4+)-graphite); and -0.53 (NR-woven graphite) . The maximal electrical productivities obtained with sewage sludge as the biocatalyst and using a Mn(4+)-graphite anode and a Fe(3+)-graphite cathode were 14 mA current, 0.45 V potential, 1,750 mA/m(2) current density, and 788 mW/m(2) of power density . With Escherichia coli as the biocatalyst and using a Mn(4+)-graphite anode and a Fe(3+)-graphite cathode, the maximal electrical productivities obtained were 2.6 mA current, 0.28 V potential, 325 mA/m(2) current density, and 91 mW/m(2) of power density . These results show that the amount of electrical energy produced by microbial fuel cells can be increased 1,000-fold by incorporating electron mediators into graphite electrodes . These results also imply that sewage sludge may contain unique electrophilic microbes that transfer electrons more readily than E . coli and that microbial fuel cells using the new Mn(4+)-graphite anode and Fe(3+)-graphite cathode may have commercial utility for producing low amounts of electrical power needed in remote locations .

J Biomed Mater Res B Appl Biomater, 2003 Jan 15, 64(1), 13 - 8
Biocompatibility investigation and urea removal from blood by urease-immobilized HEMA incorporated poly(ethyleneglycol dimethacrylate) microbeads; Ayhan F et al.; The biocompatibility of modified and urease-immobilized poly(ethyleneglycol dimethacrylate/2-hydroxyethylmetacrylate) {poly(EGDMA/HEMA)} microbeads was tested through blood compatibility tests . Twelve percent HEMA incorporated nonporous particles of 105-125 microm were used in the research . Hydroxyl groups on microbeads were chemically modified by following a three-step procedure that is composed of activation, spacer-arm incorporation (hexamethylene diamine) and, finally, glutaraldehyde bounding . Enzyme urease was immobilized on microbead surfaces, and adsorption of blood proteins in serum and plasma, blood coagulation time, and leukocyte and platelet adhesion were tested . Incubation of 1.5 cc of biological fluid with 100 mg of urease-immobilized poly(EGDMA/HEMA) microbeads at room temperature shows that protein adsorption on surfaces occurs, but protein content after treatment was in the range of healthy people . Adsorbed albumin and total globulin amounts per gram of microbeads is much greater than fibrinogen . Immobilization of urease reduced the protein adsorption and blood coagulation times compared with those of modified microbeads . Prothrombin time (PT) was not altered much, whereas poly(EGDMA/HEMA) microbeads induced a significant increase of activated partial thromboplastin time (APTT) . The platelet and leukocyte adhesion slightly increased with the modification of poly(EGDMA/HEMA) and decreased with the introduction of urease . When blood samples were treated with urease-immobilized microbeads, BUN values of patients were lowered to almost acceptable amounts .

Best Pract Res Clin Gastroenterol, 2002 Dec, 16(6), 915 - 31
The host-microbe interface within the gut; Shanahan F; Colonization with bacteria is critical for the normal structural and functional development and optimal function of the mucosal immune system . Unrestrained mucosal immune activation in response to bacterial signals from the lumen is, however, a risk factor for inflammatory bowel disease . Therefore, mucosal immune responses to indigenous flora require precise control and an immunosensory capacity for distinguishing commensals from pathogens . The use of germ-free animal models with selective colonization strategies combined with modern molecular techniques promises to clarify the molecular signals responsible for host-flora interactions in health and disease . At least half of the resident flora cannot be cultured by conventional techniques but are identifiable by molecular methods . Collectively, the resident flora represent a virtual organ with a metabolic activity in excess of the liver and a microbiome in excess of the human genome . An improved understanding of this hidden organ holds secrets relevant to several infectious, inflammatory and neoplastic disease mechanisms.

Transfus Med, 2002 Dec, 12(6), 335 - 52
Mannan-binding lectin and its role in innate immunity; Kilpatrick DC; Mannan-binding lectin (MBL) is a plasma collectin (C-type lectin with a collagen-like domain) and is considered an important component of innate immunity . Circulating MBL is genetically determined for the major part, but plasma concentration is also markedly influenced by nongenetic factors . The carbohydrate-binding ability of MBL can be inhibited by simple sugars like mannose, fucose and N-acetylglucosamine, but its greatest avidity appears to be for repeating mannose-based structural patterns typical of microbial surfaces . By this means, MBL can bind to a wide variety of bacteria and other microbes, neutralizing them and/or opsonizing them by activating complement using the recently discovered lectin pathway of complement activation . Individual humans differ 1000-fold in MBL concentration, and individuals with low circulating MBL appear to be more vulnerable to infections in a number of clinical settings, especially when combined with secondary immune deficiency . The best evidence that MBL deficiency or insufficiency is physiologically relevant comes from a rapidly expanding literature of clinical studies . MBL insufficiency appears to be a significant risk factor for infections in infants, and for individuals of any age undergoing chemotherapy or post-transplant immunosuppression . Moreover, MBL appears to have a significant influence on the course of certain chronic diseases like rheumatoid arthritis and cystic fibrosis . Replacement therapy with a plasma-derived product is safe and seems promising, while recombinant MBL provides hope for large-scale therapeutic applications . Randomized clinical trials of MBL therapy, which are now on the horizon, should provide unambiguous evidence for the physiological significance of MBL in innate immunity.

Andrologia, 2002 Dec, 34(6), 360 - 6
Deterioration of spermatozoal plasma membrane is associated with an increase of sperm lyso-phosphatidylcholines; Glander HJ et al.; Spermatozoa with plasma membranes that lost their asymmetry or permeability for larger molecules can be identified by binding of annexin V to membrane phosphatidylserine (PS) . Paramagnetic annexin-V-conjugated microbeads (AN-MB) can be used to eliminate these spermatozoa by magnetic activated cell sorting (MACS) . Semen samples of six healthy volunteers with normal spermiogram parameters were divided into two sperm fractions by MACS as a function of bound AN-MB, and their individual lipid compositions were examined by matrix-assisted laser desorption and ionisation time-of-flight mass spectrometry (MALDI-TOF MS) . As a model system, liposomes composed of phosphatidylcholines (PC) from egg yolk were digested by phospholipase A2 (PLA2) . The MALDI-TOF mass spectra of organic extracts of both sperm subpopulations differed significantly . The ratio between lyso-phosphatidylcholine LPC 16 : 0 and PC 16 : 0/22 : 6 was approximately 2.5-4.7-fold higher (median 2.9) in the sperm group binding AN-MB than in spermatozoa with intact membrane unable to bind AN-MB . The ratio between LPC 22 : 6 and PC 16 : 0/22 : 6 was also enhanced in the spermatozoa with impaired membrane structure (factor in the range: 1.9-3.9; median 2.6) . These alterations corresponded to the effects of PLA2 on artificial phospholipids . It is concluded that spermatozoa with deteriorated membrane and exposed PS are characterized by an increased lyso-phosphatidylcholine content that is likely generated by phospholipases.

Curr Top Microbiol Immunol, 2002, 270, 93 - 108
Toll-like receptor-5 and the innate immune response to bacterial flagellin; Smith KD et al.; The innate immune system identifies the presence of infection by detecting structures that are unique to microbes and that are not expressed in the host . The bacterial flagellum (Latin, a whip) confers motility, on a wide range of bacterial species . Vertebrates, plants, and invertebrates all have evolved flagellar recognition systems that are activated by flagellin, the major component of the bacterial flagellar filament . In mammals, flagellin is recognized by Toll-like receptor-5 and activates defense responses both systemically and at epithelial surfaces . Here, we review the role for Toll-like receptor-5 in mediating the mammalian innate immune response to flagellin, and how this provides for defense against infections caused by many different species of flagellated bacteria.

Curr Top Microbiol Immunol, 2002, 270, 81 - 92
Toll-like receptors and their ligands; Barton GM et al.; The Toll-like receptors (TLRs) are key molecules involved in the recognition of pathogens by the innate immune system . This family of germ line-encoded receptors has evolved to recognize conserved features of microbes . Currently, 10 TLR family members have been identified in mammals . The number of ligands for these receptors continues to grow, and it seems clear that multiple ligands exist for each receptor . Whether engagement of different TLRs leads to differences in gene expression and thereby differences in the immune response remains to be seen . However, recent work has demonstrated that activation of TLRs is required for initiation of only certain adaptive immune responses.

Curr Top Microbiol Immunol, 2002, 270, 63 - 79
Toll receptors in Drosophila: a family of molecules regulating development and immunity; Imler JL et al.; In recent years, Toll-like receptors (TLRs) have emerged as key receptors which detect microbes and initiate an inflammatory response . The Toll receptor was originally identified and characterized 14 years ago for its role in the embryonic development of the fruit-fly Drosophila melanogaster . Subsequently, it was also shown to be an essential component of the signaling pathway mediating the anti-fungal host defense in this model organism . New factors involved in the activation of the Toll receptor or in intracytoplasmic signaling during the immune response in Drosophila have recently been identified . The existence of significant functional differences between mammalian TLRs and Drosophila Toll receptors is also becoming apparent.

Vet Dermatol, 2002 Dec, 13(6), 293 - 300
A comparative review of cutaneous pH; Matousek JL et al.; This review describes the role of pH in cutaneous structure and function . We first describe the molecules that contribute to the acidity or alkalinity of the skin . Next, differences in cutaneous pH among species, among individuals of the same species and within individuals are described . The potential functions of cutaneous pH in normal and diseased skin are analysed . For example, cutaneous pH has a role in the selection and maintenance of the normal cutaneous microbiota . In addition, cutaneous acidity may protect the skin against infection by microbes . Finally, there is evidence that a cutaneous pH gradient activates pH-dependent enzymes involved in the process of keratinization.

Cell Microbiol, 2002 Dec, 4(12), 783 - 91
Microbial entry through caveolae: variations on a theme; Duncan MJ et al.; Caveolae and lipid rafts are increasingly being recognized as a significant portal of entry into host cells for a wide variety of pathogenic microorganisms . Entry through this mechanism appears to afford the microbes protection from degradation in lysosomes, though the level to which each microbe actively participates in avoiding lysosomal fusion may vary . Other possible variations in microbial entry through caveolae or lipid rafts may include (i) the destination of trafficking after entry and (ii) how actively the microbe contributes to the caveolae lipid/raft mediated entry . It seems that, though a wide variety of microorganisms are capable of utilizing caveolae/lipid rafts in various stages of their intracellular lifestyle, there can be distinct differences in how each microbe interacts with these structures . By studying these variations, we may learn more about the normal functioning of these cellular microdomains, and perhaps of more immediate importance, how to incorporate the use of these structures into the treatment of both infectious and non-infectious disease.

Pediatr Pulmonol, 2003 Jan, 35(1), 56 - 61
Serum procalcitonin concentrations in bacterial pneumonia in children: a negative result in primary healthcare settings; Korppi M et al.; A microbe-specific diagnosis in community-acquired pneumonia (CAP) is difficult in children, and studies on nonspecific chest radiographic and host response markers have been inconsistent . Serum procalcitonin (PCT) is a newly recognized, promising marker for differentiating between bacterial and viral infections . Serum PCT was measured by a luminometric assay in 190 children with CAP diagnosed in the primary healthcare setting during a population-based study in a geographically defined population . The pneumococcal, mycoplasma, chlamydia, and viral etiology of infections was studied by an extensive serologic test panel . The median PCT concentrations were 0.47, 0.46, and 0.35 ng/mL in children aged <5 years, 5-9 years, and >/=10 years (P = 0.004) . An elevated PCT >1.0 ng/mL was seen in 12.1% and >2.0 ng/mL in only 2.1% of the children . No association was seen between severity (inpatient vs . outpatient care) and etiology of CAP (evidence for pneumococcal, mycoplasma, or chlamydia, vs . viral infection) . We conclude that serum PCT measurements have no role in the diagnosis of bacterial CAP in children in primary healthcare settings .

Environ Microbiol, 2002 Nov, 4(11), 744 - 52
Non-invasive determination of plant-associated bacteria in the phyllosphere of plants; Gau AE et al.; Epiphytic living Pseudomonas strains isolated from different Malus domestica cultivars were transformed with two reporter genes {green fluorescent protein (gfp) and luciferase (luxAB)} . The establishment and distribution of these bacteria on sterile, in vitro-propagated, and thus genetically identical, Malus domestica plants were continuously analysed with a cooled, back-illuminated, charge-coupled-device (CCD) camera system . The combination of the assessment of bioluminescence and the use of a CCD camera offer an intriguing method to study, non-invasively and in real time, plant-microbe interactions as well as the colonization of the phyllosphere by microorganisms . Here we report on the applicability and sensitivity of the method with the goal to investigate quantitatively the interaction of symbiotic and pathogenic microorganisms with the corresponding host plant . It will be shown that the three bacterial isolates of the genus Pseudomonas studied, differ considerably with respect to their establishment on the host plants . It will also be shown that the chosen host apple variety has an impact on the activity of the bacterial cultivars . Analysis by a laser scanning fluorescence microscope provides the first evidence for the mode by which the epiphytic microorganisms interact with the plant.

Immunology, 2002 Dec, 107(4), 500 - 6
Phagocytosis of bacille Calmette-Guérin-infected necrotic macrophages induces a maturation phenotype and evokes antigen-presentation functions in dendritic cells; Goldmann O et al.; The interaction of pathogens with dendritic cells (DCs) seems to play a critical role in the initiation of the immune response . Tissue damage and induction of an inflammatory reaction are events frequently associated with the progression of the infection . Although DCs are very efficient at phagocytosing pathogens, the capacity of these cells to uptake microbes from a necrotic environment has not yet been proven . Here we have investigated the ability of murine bone marrow-derived DCs to maturate and acquire antigen-presentation functions when cocultured with bacille Calmette-Guerin (BCG)-infected necrotic macrophages . Immature DCs exhibited a prominent capacity to ingest necrotic material as demonstrated by flow cytometry analysis and confocal microscopy . Furthermore, after exposure to BCG-infected necrotic macrophages, DCs underwent phenotypic changes, including the up-regulation of maturation specific markers (major histocompatibility complex class II, CD40, CD80, and CD86) and the capacity to stimulate antigen-specific CD4+ T cells with higher efficiency than when they were directly infected with a similar number of bacteria . Antigen presentation following phagocytosis of BCG-infected necrotic macrophages was demonstrated by their ability to stimulate in vitro proliferation and interferon-gamma production of antigen-specific CD4+ T cells . These results suggest that the functional changes occurring in DCs after interaction with a pathogen can be favoured when the encounter takes place in a necrotic environment and it may constitute an important mechanism for the amplification of class II-restricted immune responses induced during infection.

Gastroenterology, 2002 Dec, 123(6), 1923 - 30
Strain- and blood group-dependent binding of Helicobacter pylori to human gastric MUC5AC glycoforms; Linden S et al.; BACKGROUND & AIMS: In the stomach, Helicobacter pylori is found both in the mucus layer and adhering to the gastric epithelium . The aim of this study is to characterize the binding of H . pylori to human gastric mucins . METHODS: H . pylori strains that bind the Lewis(b) (Le(b)) structure (via the BabA adhesin) and/or sialylated structures, along with isogenic adhesion deletion mutants, were used to identify microbe-binding mucins . Gastric mucins from 5 healthy individuals, isolated by density-gradient centrifugation, were investigated for H . pylori binding at neutral pH using a microtiter-based technique . RESULTS: H . pylori strains that express the BabA adhesins were shown to bind to the MUC5AC mucin in individuals expressing the Le(b) antigen . Further fractionation with an ion-exchange chromatography revealed Le(b)-positive MUC5AC glycoforms that differed in their receptor properties for different H . pylori strains . None of the H . pylori strains studied bound to mucins from Le(b)-negative individuals . However, all strains bound to low-density, nonmucin, Le(b)-negative material on top of the gradients . CONCLUSIONS: Binding of H . pylori to human gastric MUC5AC isolated from healthy individuals is BabA dependent and mediated by the Le(b) structure presented by the mucin . However, the BabA adhesins demonstrate strain-dependent preference in binding to MUC5AC glycoforms substituted with Le(b), allowing for great interindividual variability in host-microbe interactions.

Inhal Toxicol, 2002 Nov, 14(11), 1087 - 101
Effect of liner and core materials of plasterboard on microbial growth, spore-induced inflammatory responses, and cytotoxicity in macrophages; Murtoniemi T et al.; Microorganisms, when grown on wetted plasterboards, can produce bioactive compounds capable of inducing inflammatory and toxic reactions in mammalian cells . The paper liner of plasterboard is commonly regarded as the major substrate for microbial growth . In this study, we cultured Stachybotrys chartarum, Aspergillus versicolor, Penicillium spinulosum, and Streptomyces californicus on liners and cores of plasterboards in order to examine the role of these main plasterboard components on microbial growth and the resulting bioactivity, which was assessed as the ability of microbial spores to induce inflammatory responses and to evoke cytotoxicity in mouse macrophages . The microbes, isolated from mold problem buildings, were grown under saturated humidity conditions on wetted liners and cores of six different plasterboards . The spores were collected, applied to RAW264.7 macrophages at different doses, and evaluated 24 h after exposure for their ability to evoke cytotoxicity and to stimulate production of nitric oxide (NO), tumor necrosis factor alpha (TNFalpha), and interleukin-6 (IL-6) . In general, microbial growth was better on the cores than on the liners . All of the studied microbes collected from cores induced a dose-dependent production of TNFalpha in macrophages . The TNFalpha production stimulated by spores of Stachybotrys, Aspergillus, and Streptomyces paralleled their cytotoxicity . Spores of Streptomyces and Aspergillus collected from liners were among the most potent inducers of NO and IL-6 . Good growth of Stachybotrys on cores was associated with high cytotoxicity . Penicillium grew only on cores, but it did not induce major inflammatory mediator productions, nor was it significantly cytotoxic . These results indicate that previously reported microbial growth on plasterboards and spore-induced production of important inflammatory mediators and cell death in macrophages is not only due to the paper liner of plasterboard, but the core material also has a crucial role.

Inhal Toxicol, 2002 Dec, 14(12), 1279 - 90
Nitric oxide alone is an insufficient biomarker of exposure to microbes in a moisture-damaged building; Purokivi M et al.; Several epidemiological studies have revealed a large variety of adverse health effects related to exposure to microbes in moisture damaged buildings . Recently some evidence has been reported for a biochemical linkage between microbial exposure and the respiratory symptoms suffered by the occupants . The objective of the current study was to evaluate the value of nitric oxide (NO) measurements in determining the inflammatory status of airways in inhabitants of problem buildings . NO was measured by a chemiluminescence analyzer from the exhaled air . In addition, NO was determined as its metabolite nitrite from nasal lavage (NL) and induced sputum (IS) samples and also via the expression of inducible nitric oxide synthase (iNOS) in the cells . Occupants of moisture-damaged and reference schools were studied . The sampling was performed at the end of the spring term, at the end of the summer vacation, during the winter term, and after a 1-wk winter holiday . No statistically significant differences in NO levels were detected between the studied groups or between exposure and vacation periods . iNOS was not detected from IS or NL samples of the exposed occupants . These results suggest that NO measurements alone are not sufficient to quantify airway inflammation when evaluating subjects exposed to microbes present in moisture-damaged buildings.

Biorheology, 2003, 40(1-3), 241 - 5
Characterization of cytoskeleton mechanical properties and 3D-actin structure in twisted adherent epithelial cells; Fodil R et al.; Evaluation of the cytoskeleton mechanical properties requires specific micromanipulation techniques such as the magnetic twisting cytometry technique, in which microbeads are specifically linked to the cytoskeleton via transmembrane receptors . The aim of the study was to assess the structural relationship between the bead and the cytoskeleton structure . The spatial arrangement of the CSK network was therefore studied in fixed cells probed by beads and stained for F-actin by rhodamined phalloidine . The spatial character of the actin CSK network, both in the bead neighborhood and at the cell scale, could then be studied for various degrees of fluorescent intensity from 3D-images of the actin structure, reconstructed from z-stack views obtained by confocal microscopy . Results show the feasibility of the staining/reconstruction technique which allows to reveal the three-dimensional organization of the cytoskeleton structure including an internal cytosolic structure with a high fluorescent F-actin intensity, and a sub-membranous cortical structure with a low fluorescent F-actin intensity.

J Lipid Res, 2002 Dec, 43(12), 2072 - 6
Isomerization of stable isotopically labeled elaidic acid to cis and trans monoenes by ruminal microbes; Proell JM et al.; A previous study showed that oleic acid was converted by mixed ruminal microbes to stearic acid and also converted to a multitude of trans octadecenoic acid isomers . This study traced the metabolism of one of these trans C18:1 isomers upon its incubation with mixed ruminal microbes . Unlabeled and labeled (18-{13C}trans-9 C18:1) elaidic acid were each added to four in vitro batch cultures with three cultures inoculated with mixed ruminal bacteria and one uninoculated culture . Samples were taken at 0, 12, 24, and 48 h and analyzed for 13C enrichment in component fatty acids by gas chromatography-mass spectrometry . At 0 h of incubation, enrichment was detected only in elaidic acid . By 48 h of incubation, 13C enrichment was 18% (P < 0.01) for stearic acid, 7% to 30% (P < 0.01) for all trans C18:1 isomers having double bonds between carbons six through 16, and 5% to 10% for cis-9 and cis-11 monoenes . After 48 h, 13C enrichment in the uninoculated cultures was only detected in the added elaidic acid . This study shows trans fatty acids exposed to active ruminal cultures are converted to stearic acid but also undergo enzymic isomerization yielding a multitude of positional and geometric isomers.

Clin Exp Immunol, 2002 Dec, 130(3), 370 - 8
Detection and characterization of plasma cells in peripheral blood: correlation of IgE+ plasma cell frequency with IgE serum titre; Horst A et al.; In atopic patients and patients with hyper-IgE syndrome (HIE) highly elevated IgE serum levels can be detected . Due to their very low frequency little is known about IgE-producing plasma cells (PC) in peripheral blood . We used CD138 MACS microbeads to enrich plasma cells from peripheral blood of normal donors, atopic patients and one HIE patient . CD138+ cells were mainly CD45+, CD44++, CD19dim, CD38++, CD27++, CD86+, HLA-DR+/++, CD71dim, VLA-4+, VLA-5-, CD28-, CD25-, CD69-, CLA-, CD20-, CD21- and CD22- . They show weak expression of surface Ig but high levels of intracellular Ig and they secrete Ig in culture . Thus CD138+ cells from peripheral blood show characteristics of early plasma cells . IgE+ CD138+ plasma cells could be detected in 19 of 24 normal donors with an average frequency of 0.06% IgE+ cells among CD138+ cells . Higher frequencies were detected in atopic patients, atopic patients with markedly elevated serum IgE levels and the hyper-IgE patient with an average of 0.32%, 7.21% and 6.54%, respectively . Additionally, using the recently developed cellular affinity matrix technology, we were able to detect IgE secreting plasma cells and thereby could demonstrate that most of the IgE secreting cells express CD138 . The frequency of IgE+ CD138+ cells among PBMC correlated highly significantly with serum IgE titres (r = 0.8532***), indicating that IgE secreting CD138+ cells in peripheral blood are directly related to the plasma cell pool contributing to the IgE titre.

Int J Med Microbiol, 2002 Oct, 292(5-6), 363 - 71
Molecular genetic analysis of Blastomyces dermatitidis reveals new insights about pathogenic mechanisms; Brandhorst TT et al.; Fungal pathogens have emerged as a public health menace owing to the expanding population of vulnerable patients and to a heightened exposure to fungi in our environment, particularly for the systemic dimorphic fungi that inhabit soil worldwide . A better understanding of these microbes and their pathogenic mechanisms is badly needed to further research into therapeutic options . Advances in the molecular tools for genetic manipulation of Blastomyces dermatitidis have enhanced our ability to study this poorly understood dimorphic fungal pathogen . Recent refinements in gene-transfer technique, new selection markers, reliable reporter fusions and successes in gene targeting have shed light upon the importance of the mycelium-to-yeast transition and the crucial and complex role the BAD1 adhesin plays in pathogenesis.

Zhong Yao Cai, 2002 Sep, 25(9), 655 - 6
{Effect of alcohol extract of pig bile on digestion system}; Chen B et al.; OBJECTIVE: To study effect of alcohol extract of pig bile(AEB) on digestion system . METHODS: Action of AEB in vitro and vivo were observed . RESULTS: AEB could suppress the spontaneous movement of isolated intestinal smooth muscles in rabbit, markedly antagonize the intestinal propelling movement of carbon ink and experimental diarrhea caused by castor oil in mice, obviously inhibit growth of microbe . CONCLUSIONS: AEB could improve the condition of digestion.

Biomed Tech (Berl), 2002, 47 Suppl 1 Pt 1, 213 - 6
Electro-magnetic base technology for estremely sensitive immunosensors and DNA-chips; Gorschluter A et al.; We report on the development of an innovative electro-magnetic base technology for estremely sensitive sensors allowing the electrical detection of biological analytes like antigenes or DNA as well as a simple multiple detection of binding forces occurring at specific bonds between proteins . The technology is based on the strong impact of specifically captured magnetic microbeads on an electrical current generated in a fluid by a small sensor chip with an array of activated microelectrodes . The new technological principle with the on-chip detection of analytes will be suitable for large scale applications due to its mass production compatible technologies and allow an alternative way to monitor relevant substances without the consumption of critical additional solutions and reagents.

Astrobiology, 2001 Spring, 1(1), 25 - 55
Cave biosignature suites: microbes, minerals, and Mars; Boston PJ et al.; Earth's subsurface offers one of the best possible sites to search for microbial life and the characteristic lithologies that life leaves behind . The subterrain may be equally valuable for astrobiology . Where surface conditions are particularly hostile, like on Mars, the subsurface may offer the only habitat for extant lifeforms and access to recognizable biosignatures . We have identified numerous unequivocally biogenic macroscopic, microscopic, and chemical/geochemical cave biosignatures . However, to be especially useful for astrobiology, we are looking for suites of characteristics . Ideally, "biosignature suites" should be both macroscopically and microscopically detectable, independently verifiable by nonmorphological means, and as independent as possible of specific details of life chemistries--demanding (and sometimes conflicting) criteria . Working in fragile, legally protected environments, we developed noninvasive and minimal impact techniques for life and biosignature detection/characterization analogous to Planetary Protection Protocols . Our difficult field conditions have shared limitations common to extraterrestrial robotic and human missions . Thus, the cave/subsurface astrobiology model addresses the most important goals from both scientific and operational points of view . We present details of cave biosignature suites involving manganese and iron oxides, calcite, and sulfur minerals . Suites include morphological fossils, mineral-coated filaments, living microbial mats and preserved biofabrics, 13C and 34S values consistent with microbial metabolism, genetic data, unusual elemental abundances and ratios, and crystallographic mineral forms.

Antonie Van Leeuwenhoek, 2002 Aug, 81(1-4), 373 - 83
Microbe-plant interactions: principles and mechanisms; Lugtenberg BJ et al.; The present status of research on the molecular basis of microbe-plant interactions is discussed . Principles and mechanisms which play a role in the interactions of microbial pathogens, biofertilizers, phytostimulators, rhizoremediators and biocontrol agents with the plants are treated . Special emphasis is given to colonization, phase variation, two-component systems, quorum sensing, complex regulation of the syntheses of extracellular enzymes and secondary metabolites, Type 4 pili and Type III and Type IV secretion systems.

J Infect Dis, 2002 Dec 1, 186(11), 1673 - 6 Epub 2002 Nov 01.
Prevalence study of antibody to ratborne pathogens and other agents among patients using a free clinic in downtown Los Angeles; Smith HM et al.; Norway rats (Rattus norvegicus) are hosts for various microbes . Homeless people who have contact with rats may be at risk of infection by them . The Los Angeles County Department of Health Services initiated a seroepidemiologic study among patients who used a free clinic in downtown Los Angeles; 200 serum specimens obtained for other routine assays were tested for antibodies to ratborne pathogens and other agents . The seroprevalence of antibody to hepatitis E virus in this population was 13.6%; to Bartonella elizabethae, 12.5%; to B . quintana, 9.5%; to B . henselae, 3.5%; to Seoul virus, 0.5%; and to Rickettsia typhi, 0.0% . This study found that patients and locally trapped rats had antibodies to some of the same agents.

Ann N Y Acad Sci, 2002 Oct, 974, 541 - 55
Compact optical sensor for real-time monitoring of bacterial growth for space applications; van Benthem RC et al.; During long-duration manned space missions, complex chemical and biological processes need to be managed accurately for recycling human wastes and to produce human consumables . As a result, there is increasing interest in how the characteristics of microbes are influenced by microgravity . Compact optical instrumentation allows for real-time and non-invasive measurement of bacterial growth parameters during flight experiments . In close collaboration, the National Aerospace Laboratory of the Netherlands (NLR) and Bioclear Environmental Biotechnology developed and tested an on-line optical biomass sensor successfully . The sensor concept is based on a turbidity measurement technique operating in the VIS-blue part of the light spectrum with use of blue LED sources . A diagnostic tool has been developed using com-pact spectrometers and optical fibers to characterize bacterial cultures . As a result a few sensor applications operating at different colors and sensor layouts are discussed in the paper.

J Immunol Methods, 2002 Dec 20, 271(1-2), 99 - 106
Ex vivo isolation protocols differentially affect the phenotype of human CD4+ T cells; Bernard F et al.; Leukemic T cell lines have facilitated signal transduction studies but their physiological relevance is restricted . The use of primary T lymphocytes overcomes this limitation but it has long been speculated that methodological aspects of blood collection and the isolation procedure modify the phenotype of the cell . Here we demonstrate that several characteristics of human peripheral T cells are affected by the selection conditions . A significantly higher induction of the chemokine receptor CXCR4 was observed on CD4+ lymphocytes isolated by sheep red blood cell (SRBC) rosetting and CD4 MicroBeads as compared with positively selected CD4+ cells where the antibody/bead complex was immediately detached . These latter cells expressed CXCR4 at levels equivalent to that observed on CD4+ lymphocytes obtained by negative antibody-mediated selection . Furthermore, CD4+ cells isolated by SRBC rosetting and CD4 MicroBeads formed aggregates upon in vitro culture . CD4+ lymphocytes obtained by SRBC rosetting as well as those isolated following positive selection demonstrated basal phosphorylation of the extracellular signal-regulated kinase (ERK)-2 . Altogether these data suggest that certain discrepancies concerning signal transduction in primary human T cells can be attributed to the selection conditions . Thus, it is essential to establish the parameters influenced by the isolation protocol in order to fully interpret T cell responses to antigens, chemokines, and cytokines.

J Urol, 2002 Dec, 168(6), 2655 - 8
Loss of heterozygosity on chromosome 5p13-12 predicts adverse prognosis in advanced bladder cancer independent of tumor stage and grade; Bohm M et al.; PURPOSE: The individual prognosis in patients with bladder cancer is only partially predicted by tumor stage and grade . Various molecular markers have been shown to correlate with disease progression and prognosis but few add some predictive capacity beyond that offered by standard clinical and pathological parameters . MATERIALS AND METHODS: A total of 191 urothelial carcinomas from 157 patients were analyzed . Paired normal and tumor cells were microdissected by manual and microbeam-microdissection of membrane mounted native tissue, and analyzed for loss of heterozygosity (LOH) at a critical region of LOH on chromosome 5p13-12 that is involved in bladder cancer progression . LOH data were correlated with progression-free and tumor specific survival by multivariate analysis . RESULTS: Informativity of the assay was 60.7% . Log rank analysis of 100 evaluable patients showed a progression-free survival benefit without LOH at 5p13-12 of more than 3 years (p <0.01) . Mean followup was 36 months . Multivariate analysis revealed that this benefit was not predicted by tumor stage and grade alone in advanced disease (stages T3/4 and/or N+/M+, stages III/IV) . CONCLUSIONS: LOH at the critical region on chromosome 5p13-12 is a molecular marker of adverse prognosis in advanced bladder carcinoma independent of tumor stage and grade.

Biochem Soc Trans, 2002 Nov, 30(Pt 6), 971 - 8
Factor H family proteins: on complement, microbes and human diseases; Zipfel PF et al.; At present, the human Factor H protein family represents seven multidomain, multifunctional serum proteins . This group includes the complement and immune regulators Factor H, the Factor H-like protein 1 (FHL-1) and five Factor H-related proteins proteins (FHR-1, -2, -3, -4 and -5) . Each is exclusively composed of individually folded protein domains, termed short consensus repeats (SCRs) or complement control modules . Structure-function analyses allowed the localization of the complement regulatory domain of Factor H and FHL-1 in the N-terminal region within SCRs 1-4 . In addition, multiple binding sites for C3b, heparin and microbial surface proteins were localized in the N-terminus, within the middle region and also in the C-terminus of Factor H and FHL-1 . Recent results show a central role for the C-terminus of Factor H, i.e . SCRs 19-20 . These particular domains are conserved in all FHRs identified so far, include contact points for C3b, heparin and microbial surface proteins and represent a 'hot-spot' for gene mutations in patients that suffer from the Factor H-associated form of haemolytic uraemic syndrome.

J Trace Elem Med Biol, 2002, 16(3), 155 - 60
Preliminary study on the distribution of selected elements in cancerous and non-cancerous kidney tissues; Kwiatek WM et al.; In this study special interest was given to trace elements recognized as to be carcinogenic to humans . The kidney tissue sections were analyzed in order to determine the concentrations of elements present in the sample . The Synchrotron Radiation Induced X-ray Emission (SRIXE) technique was applied using a white photon microbeam . The results from cancerous parts of the kidney tissues were compared to non-cancerous parts and to the control group . In addition the iron concentration level was determined in the serum of those patients . Two-dimensional scans are presented to illustrate the differences between perfused and not-perfused tissues . According to this study there is no significant difference in the Mn concentration between cancerous and non-cancerous parts of the kidney, but the concentrations of Cd, Cr, Ti, V, Cu, Se, and Zn are at a lower concentration level in the cancerous parts than in the non-cancerous parts . A converse observation has been made for Fe . This may be associated with different metabolism and dynamics of the cancer process and both higher vascularization and need of higher blood supply in the cancerous tissue . The two-dimensional scanning of thin kidney sections showed differences in the trace element distributions depending on the analyzed samples: perfused and non-perfused . Perfusion removed blood mostly from the peritubular capillaries while in the glomerulus some capillaries had a relatively high Fe content . A low Fe concentration was observed in nephron tubules while a converse observation has been made for Cd . This may indicate that Cd is localized in the cells but not in the blood.

Am J Surg, 2002 Nov, 184(5), 414 - 7
An ultrasensitive tumor enriched flow-cytometric assay for detection of isolated tumor cells in bone marrow of patients with breast cancer; Cabioglu N et al.; BACKGROUND: An ultrasensitive tumor enriched flow-cytometric assay was used to determine its feasibility in detection of isolated tumor cells (ITC) in bone marrow (BM) of patients with breast cancer . METHODS: Epithelial cells were removed by magnetic microbeads conjugated with an anti-cytokeratin 7/8 monoclonal antibody to enrich tumor cells in BM samples . A specific gate for MCF-7 breast cancer cells (gate(MCF-7 cells)) was also taken into consideration in addition to a gate including all enriched BM cells (gate(enriched BM cells)) in flow-cytometric analysis to enhance the specificity of the method . RESULTS: Nineteen patients with stage I/II were evaluated . Ten patients (53%) were found to have cytokeratin positive (CK(+)) cells according to the gate(enriched BM cells) whereas 6 patients (32%) had CK(+) cells when the gate(MCF-7 cells) was taken into account . CONCLUSIONS: New strategies in nonmorphological ultrasensitive techniques might be useful to categorize patients with ITCs having different tumor morphology and characteristics.

Nature, 2002 Nov 14, 420(6912), 182 - 6
Non-redundant role of the long pentraxin PTX3 in anti-fungal innate immune response; Garlanda C et al.; Pentraxins are a superfamily of conserved proteins that are characterized by a cyclic multimeric structure . The classical short pentraxins, C-reactive protein (CRP) and serum amyloid P component (SAP), are acute-phase proteins produced in the liver in response to inflammatory mediators . Short pentraxins regulate innate resistance to microbes and the scavenging of cellular debris and extracellular matrix components . In contrast, long pentraxins have an unrelated, long amino-terminal domain coupled to the carboxy-terminal pentraxin domain, and differ, with respect to short pentraxins, in their gene organization, chromosomal localization, cellular source, and in their stimuli-inducing and ligand-recognition ability . To investigate the in vivo function of the long pentraxin PTX3, we generated mice deficient in Ptx3 by homologous recombination . Ptx3-null mice were susceptible to invasive pulmonary aspergillosis . Ptx3 binds selected microbial agents, including conidia of Aspergillus fumigatus, and we found that susceptibility of Ptx3-null mice was associated with defective recognition of conidia by alveolar macrophages and dendritic cells, as well as inappropriate induction of an adaptive type 2 response . Thus, the long pentraxin Ptx3 is a secreted pattern-recognition receptor that has a non-redundant role in resistance to selected microbial agents, in particular to the opportunistic fungal pathogen Aspergillus fumigatus.

Nat Prod Rep, 2002 Oct, 19(5), 617 - 49
Natural guanidine derivatives; Berlinck RG; The chemistry (isolation, biosynthesis and synthesis) and biological activities of natural products bearing a guanidine function are reviewed, including macrocyclic derivatives from terrestrial microbes, peptides from cyanobacteria and guanidine alkaloids from marine invertebrates . The review contains 258 references.

J Infect Dis, 2002 Dec 1, 186 Suppl 2, S254 - 8
New technologies, human-microbe interactions, and the search for previously unrecognized pathogens; Relman DA; Evidence suggests that a significant number of clinically important microbial pathogens remain unrecognized . Observations from the natural world, from patterns of disease in human populations, from the bedside, and from the clinical laboratory all contribute to this body of evidence . A variety of acute and chronic neurologic syndromes illustrate this point; despite features of infection, most cases of aseptic meningitis, encephalitis, and cerebral vasculitis cannot be assigned a microbiologic diagnosis . The development and clinical application of molecular methods have led to the discovery of novel members of the endogenous normal flora as well as putative disease agents . Current challenges include the establishment of criteria for disease causation and further characterization of the human microbiome during states of health . These challenges and the goal of understanding microbial contributions to inflammatory disease may be addressed effectively through the thoughtful integration of modern technologies and clinical insight.

J Hazard Mater, 2002 Dec 2, 95(3), 305 - 29
Factors affecting air sparging remediation systems using field data and numerical simulations; Benner ML et al.; Field data from five air sparging sites were used to assess the effect of several soil, contaminant, and air sparging system factors on the removal time and associated costs required to reach specified clean-up criteria . Numerical simulations were also performed to better assess the field data and to expand the data sets beyond the five field sites . Ten factors were selected and evaluated individually over a range of values based on information from practitioners and the literature . Trends in removal time and removal cost to reach a specified clean-up criterion were analyzed to ascertain the conditions controlling contaminant removal with variations in each factors' value . A linear sensitivity equation was used to quantify system dynamics controlling the observed contaminant removal trends for each factor . Factors found most critical across all field sites in terms of removal time and/or cost were contaminant type, sparge pulsing schedule, number of wells, maximum biodecay rate, total soil porosity, and aquifer organic carbon content . Factors showing moderate to low effect included the depth of the sparge point below the water table, air injection rate/pressure, horizontal air conductivity, and anisotropy ratio . At each field site, subsurface coverage of sparged air, sparged air residence time, contaminant equilibrium in the system, contaminant phase distribution, oxygen availability to microbes, and contaminant volatility seem to control the system responses and were affected by one or more of the 10 factors evaluated.

J Microsc, 2002 Nov, 208(Pt 2), 77 - 83
Impairment of cytoskeleton-dependent vesicle and organelle translocation in green algae: combined use of a microfocused infrared laser as microbeam and optical tweezers; Holzinger A et al.; A Nd-YAG laser at 1064 nm is used as optical tweezers to move intracellular objects and a laser microbeam to cause impairment of cytoskeleton tracks and influence intracellular motions in desmidiaceaen green algae . Naturally occurring migrations of large nuclei are inhibited in Micrasterias denticulata and Pleurenterium tumidum when the responsible microtubules are targeted with a laser microbeam generating 180 mW power in the focal plane . Impairment of the microtubule tracks appears to be irreversible, as the nucleus cannot pass the former irradiated area in Pleurenterium or remains abnormally dislocated in Micrasterias . The actin filament-dependent movement of secretory vesicles and smaller particles can be manipulated by the same IR-laser at 90 mW when functioning as optical tweezers . In Closterium lunula particles are displaced from their cytoplasmic tracks for up to 10 micro m but return to their tracks immediately after removing the light pressure gained by the optical tweezers . The cytoplasmic tracks consist of actin filament cables running parallel to the longitudinal axis of Closterium cells as depicted by Alexa phalloidin staining and confocal laser scanning microscopy . Dynamics and extensibility of the cytoplasmic strands connecting particles to the tracks are also demonstrated in the area of large vacuoles which are surrounded by actin filament bundles . In Micrasterias trapping of secretory vesicles by the optical tweezers causes irreversible malformations of the cell shape . The vesicle accumulation itself dissipates within 30 s after removing the optical tweezers, also indicating reversibility of the effects induced, in the case of actin filament-mediated processes.

Insect Mol Biol, 2002 Dec, 11(6), 517 - 25
Genomic organization and regulation of three cecropin genes in Anopheles gambiae; Zheng XL et al.; Three cecropin genes (AgCecA-C) were identified from Anopheles gambiae, a major vector for malaria in sub-Saharan Africa . These genes form a cluster with AgCecA and AgCecB positioned in opposite orientation, while AgCecC is downstream of AgCecA in the same direction . One intron is present in each of these three genes . Motif searches of promoter regions revealed elements that could be regulated by the NF-kappaB family of transcriptional regulators . The divergent promoter (1186 nucleotides in length) between CecA and CecB and the promoter for CecC were analysed by transfection in An . gambiae cell lines . Results showed that these promoters were up-regulated by lipopolysaccharide . The activity was further elevated when heat-inactivated microbes were used to challenge the cell line . At least one NF-kappaB site was required for inducible expression of both CecA and CecB.

J Biomed Opt, 2002 Oct, 7(4), 532 - 7
Quantum-dot nanocrystals for ultrasensitive biological labeling and multicolor optical encoding; Gao X et al.; Semiconductor nanoparticles in the size range of 2-6 nm are of great current interest, not only because of their size-tunable properties but also because of their dimensional similarity with biological macromolecules (e.g., nucleic acids and proteins) . This similarity could allow an integration of nanomaterials with biological molecules, which would have applications in medical diagnostics, targeted therapeutics, and high-throughput drug screening . Here we report new developments in preparing highly luminescent and biocompatible CdSe quantum dots (QDs), and in synthesizing QD-encoded micro- and nano-beads in the size range of 100 nm-10 microm . We show that the optical properties of ZnS-capped CdSe quantum dots are sensitive to environmental factors such as pH and divalent cations, leading to the potential use of quantum dots in molecular sensing . We also show that chemically modified proteins can be used to coat the surface of water-soluble QDs, to restore their fluorescence, and to provide functional groups for bioconjugation . For multiplexed optical encoding, we have prepared large microbeads with sizes similar to that of mammalian cells, and small nanobeads with sizes similar to that of viruses.

HNO, 2002 Nov, 50(11), 984 - 8
{The influence of bioceramics on phagocytosis of human leukocytes}; Koscielny S et al.; BACKGROUND: After implantation of biomaterials in the regions of head and neck with resident microbial contamination the interaction between the implant and microbes play an important role for the success of the implantation . The host immune defence is important for the outcome after implantation, too . Phagocytosis plays an important role in the human immune response on infections . MATERIAL AND METHODS: The method described by Suess was used to investigate and measure the influence of the bioceramics Bioverit((R)) and Al(2)O(3)-ceramic on phagocytosis of yeast by human leukocytes . RESULTS: The bioceramics showed no statistically significant influence on phagocytosis function by human leukocytes . There was a tendency towards lower phagocytosis rates in all samples with bioceramics . CONCLUSIONS: The bioceramics Bioverit((R)) and Al(2)O(3) ceramic have no influence on phagocytosis of human leukocytes . In conclusion these biomaterials did not cause any inhibition of this important part of the human immune response on microbial infections after alloplastic implantation in head and neck regions.

Proc Natl Acad Sci U S A, 2002 Nov 12, 99(23), 15107 - 11 Epub 2002 Nov 04.
East Asian genotypes of Helicobacter pylori strains in Amerindians provide evidence for its ancient human carriage; Ghose C et al.; Phylogenies of indigenous microbes have been used as surrogates for the origins of the hosts that carry them . Conversely, polymorphisms may be used to date the spread of a microbial species when information about their host populations is available . Therefore, we examined polymorphisms in Helicobacter pylori, which persistently colonize the human stomach, to test the hypothesis that they have been ancient inhabitants of humans . Three H . pylori loci that previously have been shown to have phylogeographic affinity have been analyzed for two populations with different ethnic origins from Venezuela . In a group of Amerindian subjects from Amazonia, East Asian H . pylori genotypes were present for each of the loci examined but were absent in a mestizo population from Caracas . These findings provide evidence that H . pylori has been present in humans at least since ancestors of Amerindians migrated from Asia more than 11,000 years ago.

Environ Health Perspect, 2002 Nov, 110(11), 1119 - 25
Mycobacterium terrae isolated from indoor air of a moisture-damaged building induces sustained biphasic inflammatory response in mouse lungs; Jussila J et al.; Occupants in moisture-damaged buildings suffer frequently from respiratory symptoms . This may be partly due to the presence of abnormal microbial growth or the altered microbial flora in the damaged buildings . However, the specific effects of the microbes on respiratory health and the way they provoke clinical manifestations are poorly understood . In the present study, we exposed mice via intratracheal instillation to a single dose of Mycobacterium terrae isolated from the indoor air of a moisture-damaged building (1 X 10(7), 5 X 10(7), or 1 X 10(8) microbes) . Inflammation and toxicity in lungs were evaluated 2 hr later . The time course of the effects was assessed with the dose of 1 X 10(8) bacterial cells for up to 28 days . M . terrae caused a sustained biphasic inflammation in mouse lungs . The characteristic features for the first phase, which lasted from 6 hr to 3 days, were elevated proinflammatory cytokine {i.e., tumor necrosis factor alpha (TNF-alpha) and interleukin-6 (IL-6)} levels in the bronchoalveolar lavage fluid (BALF) . TNF-alpha was produced in the lungs more intensively than was IL-6 . Neutrophils were the most abundant cells in the airways during the first phase, although their numbers in BALF remained elevated up to 21 days . The characteristics of the second phase, which lasted from 7 to 28 days, were elevated TNF-alpha levels in BALF, expression of inducible nitric oxide synthase in BAL cells, and recruitment of mononuclear cells such as lymphocytes and macrophages into the airways . Moreover, total protein, albumin, and lactate dehydrogenase concentrations were elevated in both phases in BALF . The bacteria were detected in lungs up to 28 days . In summary, these observations indicate that M . terrae is capable of provoking a sustained, biphasic inflammation in mouse lungs and can cause a moderate degree of cytotoxicity . Thus, M . terrae can be considered a species with potential to adversely affect the health of the occupants of moisture-damaged buildings.

J Fam Health Care, 2002, 12(1), 15 - 9
"Too clean for our own good?": current issues in home hygiene; Pickup J; The public is confused by apparently conflicting messages about the need for hygiene to prevent food poisoning and other infectious intestinal disease (IID) and the hypothesis that the increase in atopic disease may be linked to lack of exposure to microbes in early childhood . The consensus of hygiene experts is that the public needs to understand what constitutes effective hygiene and how to target key household areas . Handwashing is particularly important, as are cleanliness and disinfection of food preparation surfaces . The issues are discussed and practical tips are given to pass on to families.

J Med Chem, 2002 Nov 7, 45(23), 5173 - 81
Synthesis of classical and nonclassical, partially restricted, linear, tricyclic 5-deaza antifolates; Gangjee A et al.; Seven novel 2,4-diamino-5-deaza-6,7,8,9-tetrahydropyrido{3,4-g}pteridine derivatives 3-9 with different benzyl and a benzoyl substitution at the N7 position were designed and synthesized, as classical and nonclassical, partially restricted, linear tricyclic 5-deaza antifolates . The purpose was to investigate the effect of conformational restriction of the C6-C9 (tau(1)) and C9-N10 (tau(2)) bonds via an ethyl bridge from the N10 to the C7 position of 5-deaza methotrexate (MTX) on the inhibitory potency against dihydrofolate reductase (DHFR) from different sources and on antitumor activity . The synthetic methodology for most of the target compounds was a concise five-step total synthesis to construct the tricyclic nucleus, 2,4-diamino-5-deaza-7H-6,7,8,9-tetrahydropyrido{3,4-g}pteridine (23), followed by regioselective alkylation of the N7 nitrogen . Biological results indicated that this partial conformational modification for the classical analogue N-{4-{(2,4-diamino-5-deaza-6,7,8,9-tetrahydropyrido{3,4-g}pteridin-7-yl)methyl}benzoyl}-L-glutamic acid 3 was detrimental to DHFR inhibitory activity as well as to antitumor activity compared to MTX or 5-deaza MTX . However, the classical analogue 3 was a better substrate for folypolyglutamate synthetase (FPGS) than MTX . These results show that a classical 5-deaza folate partially restricted via a bridge between the N10 and C7 positions retains FPGS substrate activity and that the antitumor activity of classical tricyclic analogues such as 3 would be influenced by FPGS levels in tumor systems . Interestingly, the nonclassical analogues 4-9 showed moderate to good selectivity against DHFR from pathogenic microbes compared to recombinant human DHFR . These results support the idea that removal of the 5-methyl group of piritrexim along with restriction of tau(1) and tau(2) can translate into selectivity for DHFR from pathogens.

Trends Immunol, 2002 Nov, 23(11), 509 - 12
Endogenous ligands of Toll-like receptors: implications for regulating inflammatory and immune responses; Beg AA; Toll-like receptors (TLRs) have a crucial role in regulating immunity against microbial agents . Recent studies indicate that these receptors might also have an important role in regulating responses to endogenous stimuli, such as necrotic cells, heat-shock proteins and extracellular matrix breakdown products . Specifically, TLR2 and TLR4 were shown to mediate expression of inflammatory genes and trigger dendritic-cell 'maturation' by these agents . These intriguing findings suggest that the ancient family of TLRs are involved in the recognition, not only of microbes, but also of endogenous harmful stimuli . However, potential complications associated with microbial contamination of endogenous agents and the specific nature of in vivo responses induced by these agents remain to be determined.

Best Pract Res Clin Haematol, 2002 Jun, 15(2), 411 - 26
Iron and infection: competition between host and microbes for a precious element; Marx JJ; During infection microbes attack host tissues, causing damage to specific organs, sepsis or even death . For proliferation microbes desperately need iron for which they have to compete with the host . Micro-organisms have developed an abundant number of strategies to acquire iron from their specific environment and to transport the element to sites of incorporation into biologically important molecules . As part of the non-specific defence mechanisms against infection, the body modifies iron metabolism in order to make iron less available for micro-organisms . Such processes have a profound effect on the immune system and are also expressed in other forms of inflammation . Microbial iron transport systems are explored as targets for antibiotic treatment and vaccines . In particular, iron chelators, used for the treatment of iron overload may become important drugs for fighting bacterial and viral infections.

Curr Biol, 2002 Oct 15, 12(20), 1762 - 6
Atypical protein kinase C-zeta is essential for delayed phagocytosis of Helicobacter pylori; Allen LA et al.; Phagocytosis is a rapid actin-dependent endocytic process used by macrophages and neutrophils to ingest and kill microorganisms . Perturbation of phagocytosis is central to the ability of some pathogenic microbes to cause disease, and we demonstrated previously that the ulcerogenic bacterium Helicobacter pylori (Hp) actively retards its uptake by macrophages and subsequently persists inside novel vacuoles called megasomes . Neither the receptor that mediates Hp binding nor the signaling pathways that regulate bacterial engulfment have been defined . Nevertheless, the fact that other phagocytic stimuli do not exhibit delayed phagocytosis suggests that Hp may be ingested by a unique mechanism . We now show that Hp transiently activated protein kinase C (PKC) in macrophages and that atypical PKCzeta and novel PKC(epsilon), but not conventional PKC(alpha), accumulated on forming phagosomes . Pharmacologic agents, isoform-selective pseudosubstrate peptides, and antisense oligonucleotides demonstrated that PKC(zeta) regulated local actin polymerization and bacterial engulfment, whereas other PKC isoforms did not . In contrast, opsonization of Hp with immunoglobulin G (IgG) induced rapid PKC(zeta)-independent uptake and enhanced killing of ingested bacteria . A role for atypical PKCs in phagocytosis has not been described . We conclude that Hp defines a new phagocytic pathway in macrophages that is regulated by PKC(zeta).

Oncogene, 2002 Oct 31, 21(50), 7642 - 55
Involvement of nectin in the localization of junctional adhesion molecule at tight junctions; Fukuhara A et al.; Junctional adhesion molecule (JAM) is a Ca2+-independent immunoglobulin-like cell-cell adhesion molecule which localizes at tight junctions (TJs) . Claudin is a key cell-cell adhesion molecule that forms TJ strands at TJs . JAM is associated with claudin through their cytoplasmic tail-binding protein, ZO-1 . JAM is furthermore associated with Par-3, a cell polarity protein which forms a ternary complex with Par-6 and atypical protein kinase C . Nectin is another Ca2+-independent immunoglobulin-like cell-cell adhesion molecule which localizes at adherens junctions (AJs) . Nectin is associated with E-cadherin through their respective cytoplasmic tail-binding proteins, afadin and catenins, and involved in the formation of AJs cooperatively with E-cadherin . We show here that nectin is furthermore involved in the localization of JAM at TJs . During the formation of the junctional complex consisting of AJs and TJs in Madin-Darby canine kidney (MDCK) cells, JAM was recruited to the nectin-based cell-cell adhesion sites . This recruitment of JAM was inhibited by nectin inhibitors, which inhibited the trans-interaction of nectin . Microbeads coated with the extracellular fragment of nectin, that interacted with cellular nectin, also recruited JAM to the bead-MDCK cell contact sites . Furthermore, when cadherin-deficient L fibroblasts stably expressing both exogenous JAM and nectin (nectin-JAM-L cells) were co-cultured with L fibroblasts expressing only nectin (nectin-L cells), JAM was concentrated at the cell-cell adhesion sites between nectin-JAM-L and nectin-L cells without the trans-interaction of JAM . Analyses of the localization and immunoprecipitation of JAM revealed that it was associated with nectin through afadin and ZO-1 . These results suggest that nectin has a role in the localization of JAM at TJs in the process of the formation of the junctional complex in epithelial cells.

Bone, 2002 Oct, 31(4), 479 - 87
Unique alignment and texture of biological apatite crystallites in typical calcified tissues analyzed by microbeam X-ray diffractometer system; Nakano T et al.; Preferential orientation of biological apatite (Ap) crystallites in typical calcified tissues of rabbit ulna, rabbit skull, and monkey dentulous mandible was investigated using a microbeam X-ray diffractometer, with a beam spot of 100 microm in diameter, to clarify relationship between the Ap orientation and mechanical function . Preferential alignment of the c-axis of the biological Ap was evaluated by the relative intensity between (002) and (310) diffraction peaks . Preferential alignment of biological Ap in each calcified tissue varied depending on the shape and stress condition in vivo; that is, the c-axes of biological Ap in the rabbit ulna and the rabbit skull bone were preferentially observed as a one-dimensional orientation along the longitudinal axis and a two-dimensional orientation along the surface, respectively . Precise analysis of the preferential alignment along the skull surface showed an elliptical distribution of the c-axis of biological Ap elongating along the suture inside the skull surface of both lamina exterior and interior . The c-axis of biological Ap in a monkey dentulous mandible basically aligned along the mesiodistal direction in the flat bone, but this alignment changed along the normal direction to the flat bone surface parallel to the biting direction near the tooth, due to the force of mastication . It was concluded that the microscale measurement of biological Ap texture is one of the useful new methods for evaluating mechanical function and stress distribution in vivo in calcified tissues .

Hepatogastroenterology, 2002 Nov-Dec, 49(48), 1514 - 6
Microencapsulated multicellular spheroid of rat hepatocytes transplanted intraperitoneally after 90% hepatectomy; Hamazaki K et al.; BACKGROUND/AIMS: The aim of this preliminary study was to investigate the metabolic activity of hepatocyte spheroids encapsulated with agarosehydrogel in vitro and the effect of encapsulated hepatocyte spheroids transplanted intraperitoneally on survival in the 90% hepatectomized rats for preparing future xeno-hepatocyte spheroids transplantation . METHODOLOGY: Hepatocytes were prepared by Seglen's method and cultured with epidermal growth factor . Hepatocytes formed spheroids 4 days after inoculation . Hepatocyte spheroids were encapsulated into 5% concentration agarose-hydrogel microbeads before being transplanted into the peritoneum of the rats . RESULTS: Hepatocyte spherois showed better metabolic activity compared to isolated hepatocytes . Hepatocyte spheroids function cultured in vitro were not deteriorated by encapsulation with agarose-hydrogel . Survival rates of 90% hepatectomized rats were improved by the intraperitoneal transplantation of encapsulated hepatocyte spheroids . CONCLUSIONS: Rat hepatocyte spheroids encapsulated with agarose-hydrogel and transplanted intraperitoneally were considered as effective for the improvement of survival rates in acute liver failure produced by 90% hepatectomy.

Anal Bioanal Chem, 2002 Oct, 374(4), 626 - 30 Epub 2002 Aug 22.
Non-destructive 3D-characterization of Zn 2-2x Cu x In x S 2-thin films with ion beam analysis; Spemann D et al.; Thin layers of ZnS-CuInS(2) mixed crystals (called ZCIS) are promising absorber materials for thin film solar cell applications . The ZCIS-films investigated in this study were grown on (001)GaP, SiO(2) and CeO(2)/Al(2)O(3) with different elemental compositions by Pulsed Laser Deposition (PLD) . In order to optimize the sample preparation process a quantitative three-dimensional (i.e . laterally and depth resolved) determination of the compositions and thicknesses of the ZCIS-films is needed . It is demonstrated how this difficult analytical task can be addressed with ion microbeam analysis . For this purpose the films have been analysed non-destructively by means of Rutherford Backscattering Spectrometry (RBS) and Particle Induced X-ray Emission (PIXE) using a 2 MeV He(+) ion microbeam at the high-energy ion nanoprobe LIPSION . A large variation in film thickness caused by particulates deposited on the film was observed . The elemental compositions of the film and the particulates have been determined and compared with the target composition . The deviations found varied substantially for the individual elements . It could be concluded from these measurements, that the quality of the sintered PLD-target is of crucial importance for the roughness of the films . Furthermore concentration-depth-profiles of the individual elements have been derived non-destructively by means of RBS.

Blood, 2003 Jan 15, 101(2), 476 - 84 Epub 2002 Aug 22.
CD28 costimulation and immunoaffinity-based selection efficiently generate primary gene-modified T cells for adoptive immunotherapy; Berger C et al.; The introduction of an inducible suicide gene has been proposed as a strategy to exploit the antitumor reactivity of donor T cells after allogeneic hematopoietic stem cell transplantation but permit control of graft-versus-host disease . However, there are several obstacles to this approach that may impair the ability of T cells to function and survive in vivo . These include the requirement for in vitro activation or long-term culture to introduce the transgene and obtain therapeutic cell numbers, the toxicity of drug selection to enrich transduced cells, and the immunogenicity of the transgene-encoded products . Here we have developed a transduction and selection strategy for generating large numbers of polyclonal T cells transduced with a retroviral vector encoding the human low-affinity nerve growth factor receptor (LNGFR) for selection and a Fas-based suicide construct (LV'VFas) . Ligation of CD28 in conjunction with a T-cell receptor signal permitted efficient transduction, substantially promoted T-cell growth, and contributed to the generation of gene-modified T cells that retained clonal diversity, functional properties, and a homing receptor profile similar to untransduced peripheral blood lymphocytes . Microbeads conjugated directly to antibody specific to LNGFR significantly improved the immunomagnetic selection of LV'VFas-modified T cells and assisted in scaling of the selection procedure to therapeutic cell numbers . Thus, these studies identified a strategy that requires only a brief ex vivo culture and does not use drug selection to obtain large numbers of functional gene-modified polyclonal T cells that can be used for adoptive immunotherapy.

Eur Respir J Suppl, 2001 Dec, 34, 3s - 17s
Cytokines and the lung; Toews GB; Cytokines are signal molecules that induce movement, differentiation, growth and death of many cell types . Cytokines generate these effects through interactions with receptors, which relay a signal into the cell triggering a response . Cytokine-receptor interactions are promiscuous; a combining site of any receptor can bind many ligands . Promiscuity allows for the generation of agonists, alternative ligands that activate a receptor in a way similar to the normal ligands and antagonists, ligands that bind to a receptor, but neutralize the effects of an agonist . Cytokine-receptor interactions induce many diverse (pleiotropic) effects . Cytokine-receptor interactions are redundant; several cytokines can perform the same function . Mammalian hosts use cytokines to maintain homeostasis and to provide signals crucial to host responses to invading microbes and other injurious agents . Cytokines are the molecular messages, which: 1) initiate and amplify inflammatory and immune responses by recruiting and activating cells; 2) regulate the activation and differentiation of T- and B-lymphocytes, whose functions are crucial to specific cell-mediated immunity; and 3) initiate and regulate local repair processes critical to the resolution of inflammatory responses . Further studies of cytokines and their receptors should provide a framework for therapeutic interventions in patients with dysregulated inflammatory responses.

J Immunol, 2002 Nov 1, 169(9), 4697 - 701
Cutting edge: impaired Toll-like receptor expression and function in aging; Renshaw M et al.; Toll-like receptors (TLR) are pattern recognition receptors that recognize conserved molecular patterns on microbes and link innate and adaptive immune systems . We investigated whether the enhanced susceptibility to bacterial, yeast, and viral infections and poor adaptive immune responses in aging are a result of diminished expression and function of TLRs . We examined the expression and function of all murine TLRs on macrophages from young and aged mice . Both splenic and activated peritoneal macrophages from aged mice expressed significantly lower levels of all TLRs . Furthermore, macrophages from aged mice secreted significantly lower levels of IL-6 and TNF-alpha when stimulated with known ligands for TLR1 and 2, 2 and 6,TLR3, TLR4, TLR5, and TLR9 when compared with those from young mice . These results support the concept that increased susceptibility to infections and poor adaptive immune responses in aging may be due to the decline in TLR expression and function.

APMIS, 2002 Aug, 110(7-8), 515 - 22
Mixed microbial aetiology of community-acquired pneumonia in children; Korppi M; Seven paediatric studies on community-acquired pneumonia with serological methods for both viruses and bacteria have been published, allowing the evaluation of concomitant multiple etiological findings . In these studies, dual viral infection has been present in 0-14%, dual bacterial infection likewise in 0-14%, and mixed viral-bacterial infection in 3-30% of the pneumonia cases . The results confirm former clinical observations that respiratory viruses often pave the way for airway-colonising bacteria . The measured frequency of multiple infections has been dependent on the available test panel, mainly on the tests used for pneumococcal aetiology . Mixed viral-bacterial infections have been especially common in young children under 2 years of age, reflecting the high frequency of respiratory syncytial virus infections and their tendency to induce bacterial co-infections . No microbe-specific viral-bacterial associations have been demonstrated . The clinical implications of mixed viral-bacterial infections, compared with viral infections alone or bacterial infections alone, have so far remained unresolved . Current guidelines recommend antibiotic therapy for all community-acquired pneumonia cases in children.

Environ Toxicol Chem, 2002 Nov, 21(11), 2301 - 9
Interaction modification among decomposers impairs ecosystem processes in lead-polluted soil; Salminen J et al.; Environmental pollution by toxicants is generally believed to lead both to direct toxic effects and indirect effects via altered species interactions in a stressed community . We examined how contamination of a coniferous forest soil floor by lead (from an abandoned shooting range area) may alter trophic interactions and decomposition processes . We constructed laboratory microcosms containing microbial-based food webs with various trophic structures: microbes alone; microbes with microbivorous-detritivorous enchytraeid worms (Cognettia sphagnetorum, a potential keystone species of boreal forest soil); and microbes, worms, and predatory mites (Lysigamasus spp.) together . The direct toxic effect of lead and the effectiveness of the predators in preying upon the worms were studied in separate experiments . Polluted humic soil (acid-extractable lead concentration was 2,720 +/- 349 mg/kg of dry soil {mean +/- standard error}) was toxic to enchytraeids, and predators effectively reduced worm populations . Positive density-dependent effects of worms on microbes and a trophic cascade from predatory mites to microbes, observed in the unpolluted humus, were not observed in the polluted humus, indicating pollution-induced interaction modification among organisms . Concomitantly, lead pollution altered the process of nutrient mineralization in the humic soil . However, causality and relative importance of direct toxicity and indirect effects of lead on the dynamics of the decomposer food web could not be pointed out . Examination of our results indicates that traditional food web models are incapable of predicting mechanisms that alter dynamics of pollution-stressed belowground food webs.

Perspect Biol Med, 2002 Fall, 45(4), 475 - 98
The ecology of height: the effect of microbial transmission on human height; Beard AS et al.; The height that adult humans achieve results from a complex interplay between genetic endowment and environmental exposures during development . We hypothesize that exposure to microbes--both exogenous pathogens and endogenous biota--are critical environmental determinants of the expression of human height in a community . Both experimental studies and historical changes in height in relation to presumed microbial transmission support this hypothesis.

Am J Physiol Regul Integr Comp Physiol, 2003 Feb, 284(2), R413 - 21 Epub 2002 Oct 10.
Ontogenesis of epithelial phosphate transport systems in goats; Huber K et al.; The rapid development of precocial goats in the first weeks after birth requires an adequate adaptation of phosphate transport systems to maintain the P homeostasis at each developmental stage . Here we examined the age-related development of Na+-Pi transport systems in small intestines, kidneys, and parotid glands of goats . Kinetic parameters were determined by brush-border membrane vesicle uptake studies, and relative expression of NaPi type II mRNA and protein was recorded by molecular biological methods . High intestinal Pi transport capacity was already present on the first day of life . Within the first 3 wk of life there seemed to be a change in the type of Na+-dependent Pi transporter, and NaPi IIb was expressed increasingly up to the fifth month of life . Renal Na+-Pi transport capacity was also high at birth, and this was associated with high expression levels of NaPi IIa mRNA, indicating the important role of this transporter for renal Pi reabsorption . At weaning an increase in both intestinal and renal Na+-Pi transport balanced the increasing requirements for Pi to establish the endogenous Pi cycle . Salivary Pi concentration and parotid NaPi II mRNA rose markedly to guarantee an adequate Pi supply for rumen microbes . We concluded that the high demand for Pi in young goats was assured by high basal Na+-Pi transport capacity of small intestines and kidney expressed continuously during ontogenesis.

Ann Ist Super Sanita, 2002, 38(2), 143 - 7
Ecotoxicological endpoints for contaminated site remediation; Wilson JJ et al.; Use of chemical criteria in assessing the potential for adverse toxic effects in contaminated sites can under or overestimate the necessary level of site cleanup required . The use of ecotoxicity testing provides a more direct assessment of adverse environmental impact . A multi-trophic level soil ecotoxicity assessment was done on soil contaminated with crude oil distilled into five different fractions based on hydrocarbon chain lengths . Results indicate that the fraction above C26 was not toxic to microbes, plants, and earthworms, when present in concentrations far above the 1000 mg/kg total petroleum hydrocarbon criterion . Our ecotoxicity test battery results indicate that weathered heavy crude oils can be much less toxic than lighter, freshly spilled diesel oils, yet using a gross measure of total petroleum hydrocarbons would not detect this differences.

Bioinformatics . 2002 Oct;18 Suppl 2:S17.
Comparative genomics of microbial pathogens and symbionts; Andersson SG et al.; We are interested in quantifying the contribution of gene acquisition, loss, expansion and rearrangements to the evolution of microbial genomes . Here, we discuss factors influencing microbial genome divergence based on pair-wise genome comparisons of closely related strains and species with different lifestyles . A particular focus is on intracellular pathogens and symbionts of the genera Rickettsia, Bartonella and BUCHNERA: Extensive gene loss and restricted access to phage and plasmid pools may provide an explanation for why single host pathogens are normally less successful than multihost pathogens . We note that species-specific genes tend to be shorter than orthologous genes, suggesting that a fraction of these may represent fossil-orfs, as also supported by multiple sequence alignments among species . The results of our genome comparisons are placed in the context of phylogenomic analyses of alpha and gamma proteobacteria . We highlight artefacts caused by different rates and patterns of mutations, suggesting that atypical phylogenetic placements can not a priori be taken as evidence for horizontal gene transfer events . The flexibility in genome structure among free-living microbes contrasts with the extreme stability observed for the small genomes of aphid endosymbionts, in which no rearrangements or inflow of genetic material have occurred during the past 50 millions years (1) . Taken together, the results suggest that genomic stability correlate with the content of repeated sequences and mobile genetic elements, and thereby indirectly with bacterial lifestyles.

J Biotechnol, 2002 Nov 13, 99(3), 187 - 98
Microbial technologies for the discovery of novel bioactive metabolites; Donadio S et al.; Soil microbes represent an important source of biologically active compounds . These molecules present original and unexpected structure and are selective inhibitors of their molecular targets . At Biosearch Italia, discovery of new bioactive molecules is mostly carried out through the exploitation of a proprietary strain collection of over 50000 strains, mostly unusual genera of actinomycetes and uncommon filamentous fungi . A critical element in a drug discovery based on microbial extracts is the isolation of unexploited groups of microorganisms that are at the same time good producers of secondary metabolites . Molecular genetics can assist in these efforts . We will review the development and application of molecular methods for the detection of uncommon genera of actinomycetes in soil DNA and for the rapid dereplication of actinomycete isolates . The results indicate a substantial presence in many soils of the uncommon genera and a large diversity of isolated actinomycetes . However, while uncommon actinomycete strains may provide an increased chance of yielding novel structures, their genetics and physiology are poorly understood . To speed up their manipulation, we have developed vectors capable of stably maintaining large segments of actinomycete DNA in Escherichia coli and of integrating site specifically in the Streptomyces genome . These vectors are suitable for the reconstruction of gene clusters from smaller segment of cloned DNA, the preparation of large-insert libraries from unusual actinomycete strains and the construction of environmental libraries.

Crit Rev Microbiol, 2002, 28(3), 249 - 79
Comparative microbial character of consumed food and drinking water; Wadhwa SG et al.; Humans ingest large numbers of microbes daily . Food provides distinctly different physical and physiological conditions from drinking water . With high concentrations of carbohydrate, protein, and ionic strength, food is much closer to the human physiological state than drinking water, which is essentially devoid of nutrients and ionic strength . Accordingly, microbes that can multiply in humans and cause disease can grow in food, but do not multiply in drinking water . Virtually all food sources contain many thousand times more bacteria than drinking water . Therefore, based on both observed microbial content and the presence of large numbers of pathogens or their indicators in food, in this country food is more of a health risk to humans than drinking water . Compounding this disparity is the fact that much food is imported with limited control over the means of production . Naturally occurring bacteria (HPC or autochthonous flora) do not have virulence factors, making their numbers irrelevant to health risk except in the case of the most severely immunocompromised--a very defined population group . Consequently, public health regulations should not be directed to eliminating naturally occurring HPC, but should be focused toward controlling pathogens through measures such as sanitary crop systems in the steps from production (e.g., quality of irrigation and fertilization, animal feed lot sanitation) through storage to consumer preparation . Food possesses a far greater risk than drinking water, and government agencies should take this fact into account when writing regulations.

Biochim Biophys Acta, 2002 Oct 10, 1573(1), 93 - 9
Zigzag motions of the myosin-coated beads actively sliding along actin filaments suspended between immobilized beads; Wakayama J et al.; The motions of myosin filaments actively sliding along suspended actin filaments were studied . By manipulating a double-beam laser tweezers, single actin filaments were suspended between immobilized microbeads . When another beads coated with myosin filaments were dragged to suspended actin filaments, the beads instantly and unidirectionally slid along the actin filaments . The video image analysis showed that the beads slid at a velocity of ca . 3-5 microm/s accompanied with zigzag motions . When beads were densely coated with myosin filaments, the sliding motions became straight and smooth . The obtained results indicate that (1) during the sliding motions, the interaction between myosin heads and actin filaments is weak and susceptible to random thermal agitations, (2) the effects of thermal agitations to the sliding motions of myofilaments are readily suppressed by mechanical constraints imposed to the filaments, and (3) the active sliding force is produced almost in parallel to the filaments axis.

Lancet Infect Dis, 2002 Oct, 2(10), 628 - 35
The meaning of microbial exposure, infection, colonisation, and disease in clinical practice; Pirofski LA et al.; The basic lexicon of infectious diseases includes the terms exposure, infection, colonisation, and disease, which are used to describe the clinical states in which the presence of a microbe in a host is suspected or discovered . Therefore, the lexicon is used to articulate an implied association between a host and a microbe . However, since it is often difficult to use the available clinical and diagnostic tools to discriminate the different ways in which microbes can exist in a host, the lexicon is often used in an ambiguous and imprecise manner . Another factor contributing to imprecise use of the lexicon is that microbial factors are often held responsible for disease pathogenesis . This relegates the part that the host plays in microbial pathogenesis to an exception, which leads to the need for qualification and modification of the terminology of infectious diseases . Recently, we proposed the "damage-response framework" to incorporate the contributions of both the host and the microbe in microbial pathogenesis in a synthesis whereby host damage was used as the common denominator to describe the outcome of the host-microbe relation . In this article, we illustrate how the application of the damage-response framework to clinical infectious diseases can clarify and make more precise the terminology used to convey the outcome of microbial infection in clinical practice.

Radiat Prot Dosimetry, 2002, 101(1-4), 393 - 8
MOSFET dosimetry on modern radiation oncology modalities; Rosenfeld AB; The development of MOSFET dosimetry is presented with an emphasis on the development of a scanning MOSFET dosimetry system for modern radiation oncology modalities . Fundamental aspects of MOSFETs in relation to their use as dosemeters are briefly discussed . The performance of MOSFET dosemeters in conformal radiotherapy, hadron therapy, intensity-modulated radiotherapy and microbeam radiation therapy is compared with other dosimetric techniques . In particular the application of MOSFET dosemeters in the characterisation and quality assurance of the steep dose gradients associated with the penumbra of some modern radiation oncology modalities is investigated . A new in vivo, on-line, scanning MOSFET readout system is also presented . The system has the ability to read out multiple MOSFET dosemeters with excellent spatial resolution and temperature stability and minimal slow border trapping effects.

Anat Rec, 2002 Nov 1, 268(3), 317 - 26
Evolution of glycosaminoglycans and their glycosyltransferases: Implications for the extracellular matrices of animals and the capsules of pathogenic bacteria; DeAngelis PL; Glycosaminoglycans (linear polysaccharides with a repeating disaccharide backbone containing an amino sugar) are essential components of extracellular matrices of animals . These complex molecules play important structural, adhesion, and signaling roles in mammals . Direct detection of glycosaminoglycans has been reported in a variety of organisms, but perhaps more definitive tests for the glycosyltransferase genes should be utilized to clarify the distribution of glycosaminoglycans in metazoans . Recently, glycosyltransferases that form the hyaluronan, heparin/heparan, or chondroitin backbone were identified at the molecular level . The three types of glycosyltransferases appear to have evolved independently based on sequence comparisons and other characteristics . All metazoans appear to possess heparin/heparan . Chondroitin is found in some worms, arthropods, and higher animals . Hyaluronan is found only in two of the three main branches of chordates . The presence of several types of glycosaminoglycans in the body allows multiple communication channels and adhesion systems to operate simultaneously . Certain pathogenic bacteria produce extracellular coatings, called capsules, which are composed of glycosaminoglycans that increase their virulence during infection . The capsule helps shield the microbe from the host defenses and/or modulates host physiology . The bacterial and animal polysaccharides are chemically identical or at least very similar . Therefore, no immune response is generated, in contrast to the vast majority of capsular polymers from other bacteria . In microbial systems, it appears that in most cases functional convergent evolution of glycosaminoglycan glycosyltransferases occurred, rather than direct horizontal gene transfer from their vertebrate hosts .

J Appl Physiol, 2002 Nov, 93(5), 1583 - 9
Modulation of decompression sickness risk in pigs with caffeine during H(2) biochemical decompression; Fahlman A et al.; In H(2) biochemical decompression, H(2)-metabolizing intestinal microbes remove gas stored in tissues of animals breathing hyperbaric H(2), thereby reducing decompression sickness (DCS) risk . We hypothesized that increasing intestinal perfusion in pigs would increase the activity of intestinal Methanobrevibacter smithii, lowering DCS incidence further . Pigs (Sus scrofa, 17-23 kg, n = 20) that ingested caffeine (5 mg/kg) increased O(2) consumption rate in 1 atm air by ~20% for at least 3 h . Pigs were given caffeine alone or caffeine plus injections of M . smithii . Animals were compressed to 24 atm (20.5-23.1 atm H(2), 0.3-0.5 atm O(2)) for 3 h, then decompressed and observed for signs of DCS . In previous studies, DCS incidence in animals without caffeine treatment was significantly (P < 0.05) lower with M . smithii injections (7/16) than in controls (9/10) . However, contrary to our hypothesis, DCS incidence was marginally higher (P = 0.057) in animals that received caffeine and M . smithii (9/10) than in animals that received caffeine but no M . smithii (4/10) . More information on gas kinetics is needed before extending H(2) biochemical decompression to humans.

Cell Immunol, 2002 Mar-Apr, 216(1-2), 31 - 42
Administration of two macrophage-derived interferon-gamma-inducing factors (IL-12 and IL-15) induces a lethal systemic inflammatory response in mice that is dependent on natural killer cells but does not require interferon-gamma; Biber JL et al.; Activation of macrophages by microbes results in the rapid production of monokines (e.g., interleukin-12 (IL-12), IL-15, and IL-18), which induce production of interferon-gamma (IFN-gamma) by natural killer (NK) cells . We examined the effects of administering IL-15 in combination with IL-12 in a murine toxicity model to determine how these two cytokines might contribute to the inflammatory state that accompanies infectious processes . The daily, simultaneous administration of IL-15 (3 x 10(5)U) and IL-12 (1 microg) to normal mice resulted in shock and 100% mortality within 3-7 days, whereas minimal toxicity was observed following the administration of IL-15 or IL-12 alone . Mice treated with IL-15 plus IL-12 exhibited lesions of the gastrointestinal tract, elevated serum levels of acute phase reactants and pro-inflammatory cytokines, and NK cell apoptosis . Neutralization of IFN-gamma, TNF-alpha, and IL-1beta was not protective in cytokine-treated mice, however, toxicity and death could be completely abrogated by depletion of NK cells . Mice deficient in the STAT4 transcription factor also exhibited complete protection while mice deficient in IFN-gamma or its downstream mediator, STAT1, did not . These findings suggest that cytokine- stimulated NK cells are able to promote systemic inflammation via the induction of STAT4-responsive genes other than IFN-gamma or TNF-alpha.

Cell Biol Int, 2002, 26(9), 791 - 9
Centrosome-dependent anisotropic random walk of cytoplasmic vesicles; Maly IV et al.; We approach the problem of an apparently random movement of small cytoplasmic vesicles and its relationship to centrosome functioning . Motion of small vesicles in the cytoplasm of BSC-1 cells was quantified using computer-assisted microscopy . The vesicles move across the cytoplasm frequently changing their directions with negligible net displacement . The autocorrelation function for consecutive velocities of individual vesicles becomes indistinguishable from zero in 10s . Variance in the displacement is proportional to time . The motion of vesicles is anisotropic: It has diffusivity along the radii drawn from the centrosome several times higher than the tangential diffusivity . This anisotropy is abolished by ultraviolet microbeam irradiation of the centrosome when the microtubule array loses radial structure . We conclude that the motion of the vesicles in the cytoplasm can be described as diffusion-like random walk with centrosome-dependent anisotropy . The present analysis quantitatively corroborates the 'trial and error' model of vesicular transport.

Microb Ecol, 2002 Nov, 44(4), 296 - 305 Epub 2002 Oct 14.
In situ spatial patterns of soil bacterial populations, mapped at multiple scales, in an arable soil; Nunan N et al.; Very little is known about the spatial organization of soil microbes across scales that are relevant both to microbial function and to field-based processes . The spatial distributions of microbes and microbially mediated activity have a high intrinsic variability . This can present problems when trying to quantify the effects of disturbance, management practices, or climate change on soil microbial systems and attendant function . A spatial sampling regime was implemented in an arable field . Cores of undisturbed soil were sampled from a 3 x 3 x 0.9 m volume of soil (topsoil and subsoil) and a biological thin section, in which the in situ distribution of bacteria could be quantified, prepared from each core . Geostatistical analysis was used to quantify the nature of spatial structure from micrometers to meters and spatial point pattern analysis to test for deviations from complete spatial randomness of mapped bacteria . Spatial structure in the topsoil was only found at the microscale (micrometers), whereas evidence for nested scales of spatial structure was found in the subsoil (at the microscale, and at the centimeter to meter scale) . Geostatistical ranges of spatial structure at the micro scale were greater in the topsoil and tended to decrease with depth in the subsoil . Evidence for spatial aggregation in bacteria was stronger in the topsoil and also decreased with depth in the subsoil, though extremely high degrees of aggregation were found at very short distances in the deep subsoil . The data suggest that factors that regulate the distribution of bacteria in the subsoil operate at two scales, in contrast to one scale in the topsoil, and that bacterial patches are larger and more prevalent in the topsoil.

Anal Bioanal Chem, 2002 Oct, 374(3), 390 - 4 Epub 2002 Sep 11.
Subcellular mass determination by 4He+ energy-loss micro-spectrometry; Deves G et al.; The scanning transmission ion microscope (STIM) has been used to determine the intracellular mass of human cultured cells . A 4He+ microbeam of 2.0 MeV energy was chosen to obtain enhanced ion-energy-loss sensitivity through the micron-thick freeze-dried cells . Local sample mass calculation, based on energy-loss conversion by use of appropriate matrix stopping powers, was performed by use of dedicated software . The method was validated with epoxy resin sections and polymer foil as analogues of biological samples in the range of (intra)cellular thickness, 150 to 3000 nm . STIM analysis resulted in less than 5% error in mass determination . 4He+ energy-loss micro-spectrometry was performed on freeze-dried human ovarian cancer cells, the mean areal mass obtained was 120 microg cm(-2) (200 microg cm(-2) in the nucleus and 250 microg cm(-2) in nucleoli) . This method is particularly useful for mass normalization of X-ray fluorescence yields resulting from particle-induced X-ray emission microanalysis (micro-PIXE) . When performed successively these two ion-beam micro-analytical methods enable the mapping of true element concentrations within single cells.

J Neuroendocrinol, 2002 Oct, 14(10), 768 - 77
Beta-endorphin cells in the arcuate nucleus: projections to the supraoptic nucleus and changes in expression during pregnancy and parturition; Douglas AJ et al.; Supraoptic nucleus oxytocin neurone activity and secretion are inhibited in late pregnancy and parturition by endogenous opioids . Here, we investigated alterations in the projections and gene expression of beta-endorphin/pro-opiomelanocortin neurones in the arcuate nucleus in the pregnant rat . All regions of the arcuate nucleus were found to contain cells immunoreactive for beta-endorphin fluorescent microbeads retrogradely transported from the supraoptic nucleus, and double-labelled neurones (beta-endorphin plus microbeads), showing that beta-endorphin neurones throughout the arcuate nucleus project to the supraoptic nucleus . There was an increase in the number of beta-endorphin-immunoreactive cells in the arcuate nucleus and an increase in the density of beta-endorphin fibres within the supraoptic nucleus and peri-supraoptic region in late pregnancy and parturition, suggesting enhanced expression of beta-endorphin and increased beta-endorphin innervation of the supraoptic nucleus . Pro-opiomelanocortin mRNA expression in the arcuate nucleus increased in late compared to early pregnancy: the number of positive neurones significantly increased in the caudal region . Fos expression (an indicator of neuronal activation) in the arcuate nucleus was colocalized in beta-endorphin neurones in both proestrus and parturient rats, but the number of positive cells did not increase during parturition, suggesting lack of activation of beta-endorphin neurones at birth . Thus, beta-endorphin cells in the arcuate nucleus project to the supraoptic nucleus and increased innervation during pregnancy may explain the enhanced endogenous opioid inhibition of oxytocin neurones.

J Am Chem Soc, 2002 Oct 16, 124(41), 12182 - 91
Synthesis and characterization of polymethacrylate-based nitric oxide donors; Parzuchowski PG et al.; A synthetic path for the preparation of methacrylic homo- and copolymers containing secondary amine groups that can be converted into nitric oxide (NO) releasing N-diazeniumdiolates is described . The polymers are obtained by a multistep procedure involving synthesis of methacrylate monomers containing boc-protected secondary amine sites, free radical benzoyl peroxide initiated polymerization, deprotection of the amine sites, and subsequent reaction of the polymers with NO in the presence of sodium methoxide . Monomers with both linear and cyclic pendant secondary amines are examined as polymer building blocks . In most cases, polymers are obtained for both types with compositions that agree well with initial monomer ratios and with number average molecular weights (M(n)) ranging from 1.69 to 2.58 x 10(6) Da . The final N-diazeniumdiolated methacrylic amine polymers are shown to release NO for extended periods of time with "apparent" t(1/2) values ranging from 30 to 60 min when suspended in phosphate buffer, pH 7.4 . Total NO loading and release for these materials can reach 1.99 micromol per mg of polymer and is proportional to the amine content of the polymer . It is further shown that by using a dimethacrylate cross-linking agent in conjunction with the various methacrylate amines, suspension polymerization methods can be employed to create small (100-200 microm) polymeric methacrylate microbeads . Such microbeads that can be sequentially deprotected and converted to NO release particles via in-situ diazeniumdiolate formation as carried out for the non-crosslinked polymers.

J Investig Allergol Clin Immunol, 2002, 12(2), 99 - 106
IL-4 supplemented B-cell cultures of allergic children show reduced IgA and IgG production in response to additional stimulation with IL-10; Nies JH et al.; BACKGROUND: Cytokines play an important role in mediating immunoglobulin switch, the secretion of protective mucosal immunoglobulins, and the development of allergic diseases . This study investigates whether B cells from allergic and healthy children have different capacities to secrete immunoglobulins after stimulation with IL-4, IL-6, IL-10, IL-11, and IL13 . METHODS: We analyzed the peripheral venous blood of 44 healthy probands and of 109 allergic patients with a mean age of 13 years, allergic to grass pollen, birch pollen, and house dust mites . Lymphocytes were isolated by a density gradient and B cells were enriched by using a Magnetic Activated Cell Separator (MACS) and anti-CD19 microbeads . B Cells were co-cultured with human CDw32 (Fc gammaRII) expressing mouse Ltk fibroblasts and mouse anti-human CD40 monoclonal antibodies (CD40 system) . The interleukins IL-4, IL-6, IL-10, IL-11, and IL-13 were supplemented in various combinations . After 14 days, concentrations of IgE, IgG, IgA, and IgM were measured in the supernatants with ELISA . RESULTS: Suppression of IgA-, IgG, and IgM- synthesis was induced by stimulation of B cells with IL-4 . After additional application of IL-10, IgA, IgG, and IgM synthesis was significantly increased . When cultures stimulated with IL-4 were additionally supplemented with IL-10, IgA, and IgG synthesis of B cells obtained from allergic individuals was significantly decreased compared to nonallergic individuals . IgE-secretion of B cells from allergic individuals was significantly increased compared to nonallergic individuals after stimulation with IL-4 . CONCLUSION: Our results implicate that IL-4 is essential for the regulation of immunoglobulin class switch to IgE and that IL-4 is an important cytokine for the development of allergic diseases . The capacity of B cells in allergic children to produce less IgA and IgG in response to additional stimulation with IL-10 of cultures supplemented with IL-4 could play an important role in mediating a mucosal immune system vulnerable to allergens . This phenomenon could contribute to the pathogenesis of allergic diseases.

Nature, 2002 Oct 3, 419(6906), 498 - 511
Genome sequence of the human malaria parasite Plasmodium falciparum; Gardner MJ et al.; The parasite Plasmodium falciparum is responsible for hundreds of millions of cases of malaria, and kills more than one million African children annually . Here we report an analysis of the genome sequence of P . falciparum clone 3D7 . The 23-megabase nuclear genome consists of 14 chromosomes, encodes about 5,300 genes, and is the most (A + T)-rich genome sequenced to date . Genes involved in antigenic variation are concentrated in the subtelomeric regions of the chromosomes . Compared to the genomes of free-living eukaryotic microbes, the genome of this intracellular parasite encodes fewer enzymes and transporters, but a large proportion of genes are devoted to immune evasion and host-parasite interactions . Many nuclear-encoded proteins are targeted to the apicoplast, an organelle involved in fatty-acid and isoprenoid metabolism . The genome sequence provides the foundation for future studies of this organism, and is being exploited in the search for new drugs and vaccines to fight malaria.

J Agric Food Chem, 2002 Oct 9, 50(21), 5751 - 80
Tomato glycoalkaloids: role in the plant and in the diet; Friedman M; Tomatoes, a major food source for humans, accumulate a variety of secondary metabolites including phenolic compounds, phytoalexins, protease inhibitors, and glycoalkaloids . These metabolites protect against adverse effects of hosts of predators including fungi, bacteria, viruses, and insects . Because glycoalkaloids are reported to be involved in host-plant resistance, on the one hand, and to have a variety of pharmacological and nutritional properties in animals and humans, on the other, a need exists to develop a better understanding of the role of these compounds both in the plant and in the diet . To contribute to this effort, this integrated review presents data on the history, composition, and nutrition of tomatoes, with special focus on the assessment of the chemistry, analysis, composition, nutrition, microbiology, and pharmacology of the tomato glycoalkaloids comprising alpha-tomatine and dehydrotomatine; their content in different parts of the tomato plant, in processed tomato products, and in wild and transgenic tomatoes; their biosynthesis, inheritance, metabolism, and catabolism; plant-microbe relationships with fungi, bacteria, viruses, insects, and worms; interactions with ergosterol and cholesterol; disruption of cell membranes; tomatine-induced tomatinases, pantothenate synthetase, steroid hydroxylases, and cytokines; and inhibition of acetylcholinesterase . Also covered are tomato-human pathogen relationships and tomatine-induced lowering of plasma cholesterol and triglycerides and enhancement of the immune system . Further research needs in each of these areas are suggested . The overlapping aspects are discussed in terms of general concepts for a better understanding of the impact of tomato glycoalkaloids in the plant in general and in food in particular . Such an understanding can lead to the creation of improved tomatoes and to improved practices on the farm and in the consumption of tomatoes.

Arch Tierernahr, 2001, 55(4), 371 - 6
Research note: effect of increasing dietary concentrate levels on microbial biotin metabolism in the artificial rumen simulation system (RUSITEC); Abel H et al.; The effect of varying hay/barley-proportions in the feed ration on biotin metabolism of rumen microbes was studied by means of the rumen simulation technique RUSITEC . The stepwise replacement of hay by barley decreased dietary biotin and the net output of biotin by the microbial metabolism . It is concluded that rumen microbes utilise more and/or synthesize less biotin with increasing proportions of dietary barley . These results indicate that a critical reconsideration of current views with regard to the supply and requirement of the high yielding dairy cow for biotin is necessary.

Curr Opin Microbiol, 2002 Oct, 5(5), 520 - 4
Microbial population genomics and ecology; DeLong EF; The origins of biological complexity in microbial ecosystems are encoded within the collective genomes of the community . Cultivation-independent genomic studies provide direct access to the genomes of naturally occurring microbes, cultivated or not . Genome-enabled approaches are now significantly advancing current knowledge of genome content, diversity, population biology and evolution in natural microbial populations.

Transplantation, 2002 Aug 27, 74(4), 537 - 40
Flow cytometric evaluation of pregnancy-induced anti-HLA immunization and blood transfusion-induced reactivation; Rebibou JM et al.; BACKGROUND: Pregnancy-induced alloimmunization (PIA) may decrease to a level that becomes undetectable by complement-dependent cytotoxicity (CDC) . Nevertheless, such alloimmunization may provoke acute rejections after kidney transplantation and lead to broad-spectrum immunizations after transfusion . Flow-cytometry (FC) was used to estimate the frequency of low-level PIA and to evaluate its influence on posttransfusion alloimmunization profiles . METHODS: To evaluate the frequency of low-level PIA, the sera of 36 women, free of CDC-detectable anti-HLA IgG (CDC-IgG- negative), were cross-matched by FC against their husband's or offspring's lymphocytes and further analyzed with human leukocyte antigen (HLA) Ag-coated microbeads (Flow-PRA One-Lambda, Canoga Park, CA) . To evaluate the influence of low-level alloimmunization on posttransfusion appearance of CDC-IgG, pretransfusion sera of a second cohort of 43 women, also CDC-IgG-negative and included in a transfusion protocol, were analyzed by Flow-PRA . Posttransfusion sera were analyzed for the development of cytotoxic IgG . RESULTS: Ten of the first cohort of 36 (27.8%) CDC-IgG-negative women showed a positive FC cross-match against the husband or offspring lymphocytes . Flow-PRA analysis confirmed that 9 of 10 positive cross-matched sera contained anti-HLA IgG . Among the 43 transfused patients, 11 of 16 (68.7%) of the women who were CDC-IgG-positive after blood transfusion showed FC-detectable IgG before transfusion; although 2 of 27 (7.4%) of the patients who remained CDC-IgG-negative after transfusion showed FC-detectable IgG before transfusion (P <0.001) . CONCLUSION: Most of the de novo anti-HLA immunizations detected by CDC after transfusion in previously pregnant women can be detected by Flow-PRA before transfusion.

J Neurosci Methods, 2002 Sep 30, 119(2), 121 - 8
Microbial origin of glutamate, hibernation and tissue trauma: an in vivo microdialysis study; Zhou F et al.; Using quantitative microdialysis in hibernating Arctic ground squirrels (AGS), striatal glutamate concentrations ({glu}(dia)) progressively increased to approximately 200 microM after 3 days of microdialysis in euthermic but not hibernating ground squirrels . Initially, the progressive increase in {glu}(dia) was thought to be related to greater tissue response in euthermic animals . Alternatively, given the vastly different body temperatures between the two groups (37 vs . 3 degrees C), glutamate might have originated from microbes, replicating at a faster rate in the warmer animals . To test these hypotheses, microdialysis was repeated using sterile technique and tissue response surrounding the probe tract was assessed in hematoxylin and eosin stained sections . Using sterile microdialysis technique, traumatic tissue response was greater in euthermic compared to hibernating tissue . However, sterile microdialysis abolished the progressive increase in glutamate . To confirm the microbial origin of glutamate we monitored {glu}(dia) collected in vitro from probes immersed in glutamine-rich liquid medium incubated at 37 degrees C . In vitro, {glu}(dia) increased as much as in vivo . Two bacteria isolated from in vitro dialysate and liquid medium were both identified as Ralstonia pickettii . Growth of these isolates as well as glutamate release was enhanced when glutamine rather than NH(4)NO(3) was added to the medium suggesting the bacteria utilize glutamine preferentially over ammonium as a nitrogen source .

World Watch, 1999 Sep-Oct, 12(5), 20 - 9
Breaking out or breaking down; Brown LR et al.; PIP: A new kind of challenge looms in several regions of the world, where the historic trend toward longer life expectancy has been sharply reversed . There are three clearly identifiable trends that are causing death rates to increase . The first is the spread of the HIV virus, which causes AIDS . As illustrated by the case of sub-Saharan Africa, the growth of the HIV epidemic damages a nation's social infrastructure, producing lingering demographic and economic effects . It reinforces conditions like poverty, illiteracy, and malnutrition . Second, the depletion of aquifers has become a major threat, particularly in India, where water tables are falling in almost every region . Water shortage leads to such problems as infectious diseases, waterborne microbes, and weakened water irrigation for farmers, which in turn leads to a diminishment of the food supply . The third threat that hangs over the future of nearly all countries where rapid population growth continues is the decline in the amount of cropland per person; this is a threat arising as a consequence of population growth and of the conversion of cropland to other uses . Land scarcity readily translates into malnutrition, hunger, rising mortality, and migration . In order to face all of these threats, leaders all over the world will need to understand that universal access to family planning is not only important for coping with resource scarcity and the spread of HIV/AIDS but is also likely to improve the quality of life for citizens of their countries .

Adv Contracept Deliv Syst, 1987 Feb, 3(1), 1 - 26
Reproductive health during adolescence: AIDS/STD and contraception; World Federation of Contraception and Health; PIP: Sex education and more widespread use of modern contraceptives are urgent needs in view of alarming increases in the rate of adolescent pregnancy, induced abortion, and sexually transmitted diseases (STDs) . Chlamydia trachomatis and nongonococcal urethritis are the most common STDs in both developed and developing countries . Other STDs that are prevalent among adolescents are herpes and gonococcal urethritis . The "hitch-hiking" phenomenon of microbes on sperm surfaces is of special clinical significance in STDs . Bacteria, fungi, and viruses hitch-hiking on the surfaces of spermatozoa adhere to surface epithelium of the female reproductive tract and are transported to the fallopian tubes and peritoneal cavity . Protective behavior such as condom usage is highly needed for sexual partners who may be carrying the acquired immunodeficiency syndrome (AIDS) virus . The risk of transmitting the AIDS virus increases with multiple sexual partners and multiple infections with other STDs . The AIDS virus, attached to the plasmalemma of spermatozoa, is transmitted to the egg during the process of fertilization . International cooperation in research in contraception for adolescents is urgently needed to allow for the transfer of skills to the Third World and the early testing of new or improved contraceptives under conditions of use in developing countries .

Gazette . 1996 Sep 30;:4 p.
On research: new contraceptive gel prevents pregnancy and STDs; Venere E; PIP: A contraceptive gel, which prevents pregnancy as well as sexually transmitted diseases, created by scientists at the Johns Hopkins University has been selected for clinical trials by the National Institutes of Health . The gel is a vaginal microbicide that kills both sperm and microbes . It also destroys white blood cells in sperm and cervical mucus that can be infected with HIV . The creators of the gel found out that an effective acidic microbicide should neither harm the cells of the vaginal lining nor kill the beneficial bacteria in the vagina . Thus they created an inverted question markacidic buffer inverted question mark that would be unable to penetrate the membranes of beneficial cells, rendering the buffer harmless to those cells . Yet, it would maintain the mild acidity which kills sperm and microbes that are sensitive to acid . The scientists are also developing ways to increase the gel's effectiveness by incorporating antibodies and vaccines . Additional research could result in a contraceptive gel lasting for 24 hours or longer . The gel, which they call BufferGel, may be marketed after undergoing extensive tests over the next 2 years .

Int J Popul Geogr, 1995 Sep, 1(1), 19 - 27
Migration theories and behavioural models; Courgeau D; "This review presents a probabilistic formulation of the decision making process, leading to a rigorous treatment of migration behaviour for projection purposes....Aggregate-level models may be applied to migration flows for which the objectively measured characteristics of areas of department and destination act as subjectively measured characteristics and stimuli....Individual-level models use event history methods of analysis to introduce a great variety of characteristics of the subject on the decision to move . They lead to projections using microsimulation models . A further step is taken in integrating macro- and microbehavioural models . The use of aggregate and individual characteristics simultaneously leads to more efficient and sophisticated projection models: the factors affecting behaviour at the micro-level cannot be inferred from aggregate studies and conversely." excerpt

Dev Commun Rep . 1987;(57):10.
Knowledge about AIDS in a Central African town; Carael M et al.; PIP: In July 1986, at the request of the Ministry of Health in Rwanda, the Rwandan Red Cross initiated a 2-year Acquired Immune Deficiency Syndrome (AIDS) education program, funded by the Norwegian Red Cross . The short daily radio spots and six 1-hour programs were produced and broadcast for 6 months on Rwandan national radio . This campaign had a major impact on the level of knowledge of AIDS among urban adults . Post-broadcast research showed an increased understanding of the HIV modes of transmission among those with higher levels of education . At least 25% of these adults reported a change in their sexual behavior in the past year . Sexual abstinence was the most common preventive measure adopted by this group . To develop an effective information strategy, the Red Cross conducted a survey in Kigali . The great majority of the 1192 men and women surveyed (98%) knew that AIDS is a disease, and 76% knew that it is caused by a microbe . 73% learned about AIDS by listening to the radio; 14% learned of it from friends and smaller percentages from newspapers, health workers, and from others . Following the radio program and assessment of the survey data, a 30-page information booklet was prepared using a question and answer format . During this ongoing 2-year public education campaign, the Rwandan Red Cross intends to distribute 25,000 booklets to opinion leaders throughout the country . 3000 copies of a more scientific document were prepared for paramedical personnel . Leaflets also will be produced targeting identified high risk groups such as prostitutes, chauffeurs, soldiers, and students . The Rwandan Red Cross will be a primary distributor of the booklets .

Can Oper Room Nurs J, 2002 Sep, 20(3), 16 - 7, 20-1
Artificial nails.. . very real risks; Porteous J; The current social trend towards personal esthetics has come into conflict with safe perioperative care practices . While artificial nails have become very popular they pose a significant risk to patients . Surgical personnel who scrub while wearing artificial nails are putting their patients at higher risk for post-surgical wound infection . Artificial nails harbour microbes and cannot be cleaned as effectively as short, natural nails . We cannot rely on surgical gloves to always contain these hand organisms . There are reported cases where artificial nails have been the cause of post-surgical infections and even death . OR personnel who scrub should not wear artificial nails.

Plant Cell, 1993 May, 5(5), 541 - 552
Cell Communication, Stochastic Cell Responses, and Anthocyanin Pattern in Mustard Cotyledons; Nick P et al.; The role of intercellular signals in plant development was investigated using phytochrome-induced formation of anthocyanin in cotyledons of white mustard as a model system . The problem was approached by irradiating different subregions of the cotyledon with a microbeam . This technique was combined with in situ hybridization of chalcone synthase mRNA after irradiation of the entire cotyledon . Individual cells that exhibited all-or-none responses with a resultant stochastic, patchy pattern were examined during early stages of anthocyanin synthesis . It was demonstrated that the responses of individual cells were subsequently integrated by long-range inhibitory signals . This process led to ordered and gradually developing patterns that could be detected when final stages were analyzed at the whole-organ level . The significance of these findings is discussed in terms of efforts toward a general understanding of photomorphogenesis in plants.

Microbes Infect, 2002 Jul, 4(8), 763 - 71
Leishmania major activates IL-1 alpha expression in macrophages through a MyD88-dependent pathway; Hawn TR et al.; Leishmania species present unusual challenges to the immune system with their capacity to downregulate inflammatory responses as well as their ability to live within macrophages . Although toll-like receptor (TLR) pathways have been implicated in the recognition of several classes of pro-inflammatory microbes, it is not known if pathogens with anti-inflammatory properties activate the host response through this family of proteins . In this study, Leishmania major stimulation of cytokine promoter-luciferase reporter constructs was examined in transfected macrophages to detect early signs of cellular activation . L . major selectively activated the promoter region of IL-1 alpha, but not IL-6, IL-8, IL-10, or an NF-kappa B reporter . IL-1 alpha mRNA expression was also stimulated by L . major, although at lower levels than lipopolysacharide-stimulated macrophages . No IL-1 alpha protein was detectable in stimulated cell lysates or culture supernatants . Transfection of macrophages with a dominant-negative version of myeloid differentiation factor 88 (MyD88), an adaptor protein which interacts with TLRs, inhibited activation of the IL-1 alpha promoter . Furthermore, stimulation of IL-1 alpha RNA expression by L . major was inhibited in peritoneal macrophages from MyD88-/- as compared to MyD88+/+ mice . These observations indicate that L . major stimulates IL-1 alpha promoter activity and mRNA expression in macrophages through MyD88-dependent pathways . However, additional anti-inflammatory pathways must also be activated which downregulate transcription and ultimately inhibit translation of the IL-1 alpha protein . Examination of promoter activation is a powerful tool for understanding the early events in macrophage activation for anti-inflammatory pathogens such as Leishmania that have mechanisms to downregulate transcription and translation.

Indoor Air, 2002 Sep, 12(3), 175 - 83
Indoor air microbes and respiratory symptoms of children in moisture damaged and reference schools; Meklin T et al.; Microbial indoor air quality and respiratory symptoms of children were studied in 24 schools with visible moisture and mold problems, and in eight non-damaged schools . School buildings of concrete/brick and wooden construction were included . The indoor environment investigations included technical building inspections for visible moisture signs and microbial sampling using six-stage impactor for viable airborne microbes . Children's health information was collected by questionnaires . The effect of moisture damage on concentrations of fungi was clearly seen in buildings of concrete/brick construction, but not in wooden school buildings . Occurrence of Cladosporium, Aspergillus versicolor, Stachybotrys, and actinobacteria showed some indicator value for moisture damage . Presence of moisture damage in school buildings was a significant risk factor for respiratory symptoms in schoolchildren . Association between moisture damage and respiratory symptoms of children was significant for buildings of concrete/brick construction but not for wooden school buildings . The highest symptom prevalence was found during spring seasons, after a long exposure period in damaged schools . The results emphasize the importance of the building frame as a determinant of exposure and symptoms.

J Immunol, 2002 Oct 1, 169(7), 3914 - 9
Bacterial flagellin is an effective adjuvant for CD4+ T cells in vivo; McSorley SJ et al.; Flagellin is secreted by many enteric bacteria and, upon reaching the basolateral membrane of the intestinal epithelium, activates Toll-like receptor 5-mediated innate immune signaling pathways . We hypothesized that any flagellin that gets beyond the epithelium might also regulate cells of the adaptive immune system . Here we demonstrate that the clonal expansion of naive DO11.10 CD4 T cells in response to OVA peptide (323-339) was enhanced 3- to 10-fold in the presence of purified bacterial flagellin in vivo . OVA-specific CD4 T cells were also shown to have undergone more cell division in vivo if flagellin was coinjected with OVA . Flagellin administration increased the expression of B7-1 on splenic dendritic cells, and coinjection of CTLA4-Ig, which is known to block B7 function in vivo, completely ablated the adjuvant effect on CD4 T cells . Therefore, a conserved bacterial protein produced by many intestinal microbes can modulate CD4 T cell activation in vivo . Such an adjuvant effect for flagellin has important implications for vaccine development and the generation of CD4 T cell responses to enteric bacteria.

J Immunol, 2002 Oct 1, 169(7), 3565 - 73
Pulmonary surfactant protein A up-regulates activity of the mannose receptor, a pattern recognition receptor expressed on human macrophages; Beharka AA et al.; Inhaled particulates and microbes are continually cleared by a complex array of lung innate immune determinants, including alveolar macrophages (AMs) . AMs are unique cells with an enhanced capacity for phagocytosis that is due, in part, to increased activity of the macrophage mannose receptor (MR), a pattern recognition receptor for various microorganisms . The local factors that "shape" AM function are not well understood . Surfactant protein A (SP-A), a major component of lung surfactant, participates in the innate immune response and can enhance phagocytosis . Here we show that SP-A selectively enhances MR expression on human monocyte-derived macrophages, a process involving both the attached sugars and collagen-like domain of SP-A . The newly expressed MR is functional . Monocyte-derived macrophages on an SP-A substrate demonstrated enhanced pinocytosis of mannose BSA and phagocytosis of Mycobacterium tuberculosis lipoarabinomannan-coated microspheres . The newly expressed MR likely came from intracellular pools because: 1) up-regulation of the MR by SP-A occurred by 1 h, 2) new protein synthesis was not necessary for MR up-regulation, and 3) pinocytosis of mannose BSA via MR recycling was increased . AMs from SP-A(-/-) mice have reduced MR expression relative to SP-A(+/+) . SP-A up-regulation of MR activity provides a mechanism for enhanced phagocytosis of microbes by AMs, thereby enhancing lung host defense against extracellular pathogens or, paradoxically, enhancing the potential for intracellular pathogens to enter their intracellular niche . SP-A contributes to the alternative activation state of the AM in the lung.

Biochem Biophys Res Commun, 2002 Sep 20, 297(2), 335 - 40
Rat parietal cells express CCK(2) receptor mRNA: gene expression analysis of single cells isolated by laser-assisted microdissection; Tommeras K et al.; Gastrin plays a crucial role in maintaining a normal cellular composition and function of the oxyntic mucosa . It has been debated for decades whether parietal cells possess cholecystokinin-2 (CCK(2)) receptors and interact directly with gastrin . We investigated whether parietal cells express CCK(2) receptor mRNA by using new molecular biology techniques . Rat oxyntic mucosal cells were dispersed and enriched by elutriation, and single parietal and ECL cells were isolated from cell smears by means of laser microbeam microdissection and laser pressure catapulting . The mRNA from each single cell was isolated and subjected to one-step multiplex or conventional reverse transcription-polymerase chain reaction and subsequent nested PCR . Specific primers for the CCK(2) receptor were used in combination with primers for H,K-ATPase and histidine decarboxylase, specific markers for parietal and ECL cells, respectively . CCK(2) receptor mRNA was detected in 25% of the rat parietal cells and 40% of the ECL cells examined.

Phonetica, 2002 Apr-Sep, 59(2-3), 134 - 49
Articulation of extreme formant patterns for emphasized vowels; Erickson D; This study examined formant, jaw and tongue dorsum measurements from X-ray microbeam recordings of American English speakers producing emphasized vs . unemphasized words containing high-front, mid-front and low vowels . For emphasized vowels, the jaw position, regardless of vowel height, was lower, while the tongue dorsum had a more extreme articulation in the direction of the phonological specification of the vowel . For emphasized low vowels, the tongue dorsum position was lower with the acoustic consequence of F1 and F2 bunched closer together . For emphasized high and mid-front vowels, the tongue was more forward with the acoustic consequence of F1 and F2 spread more apart . These findings are interpreted within acoustic models of speech production . They also provide empirical data which have application to the C/D model hypothesis that both increased lowering of jaw and enhanced tongue gesture are consequences of a magnitude increase in the syllable pulse due to emphasis . Copyright 2002 S . Karger AG, Basel

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