Bacteriological

J Exp Med, 2002 Jun 3, 195(11), 1507 - 12
Interferon-alpha and interleukin-12 are induced differentially by Toll-like receptor 7 ligands in human blood dendritic cell subsets; Ito T et al.; Dendritic cells (DCs) play a crucial role in the immune responses against infections by sensing microbial invasion through toll-like receptors (TLRs) . In humans, two distinct DC subsets, CD11c(-) plasmacytoid DCs (PDCs) and CD11c(+) myeloid DCs (MDCs), have been identified and can respond to different TLR ligands, depending on the differential expression of cognate TLRs . In this study, we have examined the effect of TLR-7 ligands on human DC subsets . Both subsets expressed TLR-7 and could respond to TLR-7 ligands, which enhanced the survival of the subsets and upregulated the surface expression of costimulatory molecules such as CD40, CD80, and CD86 . However, the cytokine induction pattern was distinct in that PDCs and MDCs produced interferon (IFN)-alpha and interleukin (IL)-12, respectively . In response to TLR-7 ligands, the Th1 cell supporting ability of both DC subsets was enhanced, depending on the cytokines the respective subsets produced . This study demonstrates that TLR-7 exerts its biological effect in a DC subset-specific manner.

Front Biosci, 2002 Jun 01, 7, a117 - 25
Chronic alcohol intoxication primes Kupffer cells and endothelial cells for enhanced CC-chemokine production and concomitantly suppresses phagocytosis and chemotaxis; Bautista AP; Chemokines are involved in the pathogenesis of alcoholic hepatitis and are considered to contribute to the migration of leukocytes into the liver during chronic ethanol intoxication . This work tests the hypothesis that chronic ethanol consumption selectively enhances chemokine release by Kupffer cells and hepatic sinusoidal endothelial cells and migration of inflammatory cells into the liver . Furthermore, enhanced hepatic chemokine secretion may induce an autocrine effect on the ability of Kupffer cells and endothelial cells to chemotax and ingest microbial particles . Male Wistar rats were fed with ethanol in agar block and water for 32 weeks, and were allowed free access to solid food . Results show that after 32 weeks of feeding, leukocyte infiltration and steatosis were observed in the livers of ethanol-fed rats . The majority of the infiltrated cells were CD8+ cells . Serum ALT, endotoxin, MIP-1alpha, MCP-1 and RANTES, (but not CINC and MIP-2) were also increased in the ethanol-fed rats than in the pair-fed group . Isolated Kupffer cells from ethanol-fed rats were primed for enhanced MIP-1alpha, MCP-1, and RANTES production in vitro, while the endothelial cells were primed for enhanced MIP-1alpha release only . Chronic alcohol intoxication was also associated with increased basal H2O2 formation, enhanced nuclear translocation and binding of NF-kappaB, AP-1 and MNP-1 in Kupffer Cells . Chronic ethanol feeding significantly enhanced MNP-1 binding, but not those of NF-kappaB and AP-1 in endothelial cells . Concomitantly, chemokine-induced chemotaxis, E.coli phagocytosis and f-met-leu-phe-induced superoxide anion production by Kupffer cells were downregulated in the ethanol-fed group . Taken together these data demonstrate that prolonged alcohol consumption may compromise the host to hepatitis as a result of increased chemokine production and at the same time may suppress the innate immune function of hepatic non-parenchymal cells.

J Endod, 2002 Apr, 28(4), 269 - 71
Microbial leakage evaluation of the continuous wave of condensation; Jacobson HL et al.; Coronal leakage has been recognized as a cause of pulpal and periradicular disease . Although cleaning and shaping of the root canal system is considered paramount, obturation of the system is an important step in endodontic success . The purpose of this study was to evaluate coronal bacterial leakage in teeth obturated with the System B continuous wave of condensation technique, followed by an Obtura II backfill, versus teeth obturated using the lateral condensation technique . Sixty single-rooted bilaterally matched teeth were evaluated in this study . An anaerobic bacterial leakage model was used . Results indicate that microbial coronal leakage occurs more quickly using lateral condensation than with the System B continuous wave of condensation and Obtura II backfill . This difference was statistically significant (p < or = 0.05) . However, there was no statistical difference between groups 1 and 2 in the numbers of teeth that demonstrated bacterial leakage at the end of the study.

Nat Biotechnol, 2002 Jun, 20(6), 607 - 12
Field and pulping performances of transgenic trees with altered lignification; Pilate G et al.; The agronomic and pulping performance of transgenic trees with altered lignin has been evaluated in duplicated, long-term field trials . Poplars expressing cinnamyl alcohol dehydrogenase (CAD) or caffeate/5-hydroxy-ferulate O-methyltransferase (COMT) antisense transgenes were grown for four years at two sites, in France and England . The trees remained healthy throughout the trial . Growth indicators and interactions with insects were normal . No changes in soil microbial communities were detected beneath the transgenic trees . The expected modifications to lignin were maintained in the transgenics over four years, at both sites . Kraft pulping of tree trunks showed that the reduced-CAD lines had improved characteristics, allowing easier delignification, using smaller amounts of chemicals, while yielding more high-quality pulp . This work highlights the potential of engineering wood quality for more environmentally benign papermaking without interfering with tree growth or fitness.

J Calif Dent Assoc, 2002 May, 30(5), 376 - 82
Laser curettage: where do we stand?
Dederich DN, Drury GI.
The literature suggests that curettage has no benefit beyond traditional scaling and root planing . However, claims abound as to the benefits of curettage with the laser, including less postoperative pain, less bleeding, and reduction in microbial count . This paper explores whether any of these claims are true and whether laser curettage has any benefit in periodontal treatment.

Curr Drug Targets, 2002 Jun, 3(3), 223 - 8
Novel molecular targets for systemic lupus erythematosus; Marino M et al.; For a long time the complement cascade has been believed to be the predominant pathway to inflammation and tissue destruction in autoimmune diseases such as systemic lupus erythematosus . Recently, new evidences show that FcRs may share the primacy with complement cascade, playing an equal or greater role in the disease process . The generation of specific mouse strains deficient in individual components has clarified the different role played by complement and Fc receptors in their interaction with ICs, illustrating that complement is essential for innate immunity against microbial pathogens, requiring natural antibodies to mediate its protective effects, whereas FcyRs have evolved as the principal system for coupling antigen-antibody complexes to effector cells and initiate the inflammatory cascade . Validation of FcRs as new therapeutic targets for autoimmune diseases, in particular for Systemic Lupus Erythematosus (SLE), has been provided by a large number of studies where the biological action of soluble forms of FcyRs or of monoclonal antibodies targeting Fc receptors has been assessed . Additional support to the role of FcRs in SLE has been provided by data obtained with compounds derived from combinatorial chemistry, such as TG19320, a tetrameric tripeptide which interferes with IgG/FcgammaR interaction in vitro and prevents glomerulonephritis in vivo in a SLE susceptible mouse strain . These findings might open the way to new therapeutic approaches for disorders where the role of FcRs has been established, including not only autoimmune diseases like systemic lupus erythematosus, rheumatoid arthritis, multiple myeloma, but also acquired immunodeficiency syndrome (AIDS).

FASEB J, 2002 Jun, 16(8), 849 - 56
Regional manifestations and control of the immune system; Saadi S et al.; Although immune responses are generally considered to be systemic, local events such as interaction of complement products with blood vessels and with inflammatory cells play a pivotal role in determining the nature and manifestations of immune responses . This paper will discuss how blood vessel physiology and immunity influence one another to reach homeostasis upon exposure to an infectious agent . We review new insights into the mechanisms by which the microenvironment of tissues protects against microbial invasion yet facilitates migration of leukocytes and 'decides' whether immunity or tolerance ensues and whether, in the face of immunity, protective responses or tissue injury ensues . These 'decisions' are made based on interaction of components of normal tissues such as proteoglycans and injured tissues such as cell-associated cytokines with receptors on immune cells and blood vessels.

Appl Environ Microbiol, 2002 Jun, 68(6), 3094 - 101
Fluorescence in situ hybridization and catalyzed reporter deposition for the identification of marine bacteria; Pernthaler A et al.; Fluorescence in situ hybridization (FISH) with horseradish peroxidase (HRP)-labeled oligonucleotide probes and tyramide signal amplification, also known as catalyzed reporter deposition (CARD), is currently not generally applicable to heterotrophic bacteria in marine samples . Penetration of the HRP molecule into bacterial cells requires permeabilization procedures that cause high and most probably species-selective cell loss . Here we present an improved protocol for CARD-FISH of marine planktonic and benthic microbial assemblages . After concentration of samples onto membrane filters and subsequent embedding of filters in low-gelling-point agarose, no decrease in bacterial cell numbers was observed during 90 min of lysozyme incubation (10 mg ml(-1) at 37 degrees C) . The detection rates of coastal North Sea bacterioplankton by CARD-FISH with a general bacterial probe (EUB338-HRP) were significantly higher (mean, 94% of total cell counts; range, 85 to 100%) than that with a monolabeled probe (EUB338-mono; mean, 48%; range, 19 to 66%) . Virtually no unspecific staining was observed after CARD-FISH with an antisense EUB338-HRP . Members of the marine SAR86 clade were undetectable by FISH with a monolabeled probe; however, a substantial population was visualized by CARD-FISH (mean, 7%; range, 3 to 13%) . Detection rates of EUB338-HRP in Wadden Sea sediments (mean, 81%; range, 53 to 100%) were almost twice as high as the detection rates of EUB338-mono (mean, 44%; range, 25 to 71%) . The enhanced fluorescence intensities and signal-to-background ratios make CARD-FISH superior to FISH with directly labeled oligonucleotides for the staining of bacteria with low rRNA content in the marine environment.

Appl Environ Microbiol, 2002 Jun, 68(6), 3085 - 93
Neutrophilic Fe-oxidizing bacteria are abundant at the Loihi Seamount hydrothermal vents and play a major role in Fe oxide deposition; Emerson D et al.; A number of hydrothermal vent sites exist on the summit of the Loihi Seamount, a shield volcano that is part of the Hawaiian archipelago . The vents are 1,100 to 1,325 m below the surface and range in temperature from slightly above ambient (10 degrees C) to high temperature (167 degrees C) . The vent fluid is characterized by high concentrations of CO2 (up to 17 mM) and Fe(II) (up to 268 microM), but there is a general paucity of H2S . Most of the vents are surrounded by microbial mats that have a gelatinous texture and are heavily encrusted with rust-colored Fe oxides . Visually, the Fe oxides appeared homogeneous . However, light microscopy revealed that the oxides had different morphologies, which fell into three classes: (i) sheaths, (ii) twisted or irregular filaments, and (iii) amorphous oxides . A morphological analysis of eight different samples indicated that the amorphous oxides were overall the most abundant; however, five sites had >50% sheaths and filamentous oxides . These latter morphologies are most likely the direct result of microbial deposition . Direct cell counts revealed that all of the oxides had abundant microbial populations associated with them, from 6.9 x 10(7) to 5.3 x 10(8) cells per ml of mat material . At most sites, end point dilution series for lithotrophic Fe oxidizers were successful out to dilutions of 10(-6) and 10(-7) . A pure culture was obtained from a 10(-7) dilution tube; this strain, JV-1, was an obligate, microaerophilic Fe oxidizer that grew at 25 to 30 degrees C . A non-cultivation-based molecular approach with terminal-restriction fragment length polymorphism also indicated the common presence of Fe-oxidizing bacteria at Loihi . Together, these results indicate that Fe-oxidizing bacteria are common at the Loihi Seamount and probably play a major role in Fe oxidation . A review of the literature suggests that microbially mediated Fe oxidation at hydrothermal vents may be important globally.

Appl Environ Microbiol, 2002 Jun, 68(6), 3035 - 45
Empirical and theoretical bacterial diversity in four Arizona soils; Dunbar J et al.; Understanding patterns of biodiversity in microbial communities is severely constrained by the difficulty of adequately sampling these complex systems . We illustrate the problem with empirical data from small surveys (200-member 16S rRNA gene clone libraries) of four bacterial soil communities from two locations in Arizona . Among the four surveys, nearly 500 species-level groups ( Dunbar et al., Appl . Environ . Microbiol . 65:662-1669, 1999) and 21 bacterial divisions were documented, including four new candidate divisions provisionally designated SC1, SC2, SC3, and SC4 . We devised a simple approach to constructing theoretical null models of bacterial species abundance . These null models provide, for the first time, detailed descriptions of soil bacterial community structure that can be used to guide experimental design . Models based on a lognormal distribution were consistent with the observed sizes of the four communities and the richness of the clone surveys . Predictions from the models showed that the species richness of small surveys from complex communities is reproducible, whereas the species composition is not . By using the models, we can now estimate the required survey scale to document specified fractions of community diversity . For example, documentation of half the species in each model community would require surveys of 16,284 to 44,000 individuals . However, quantitative comparisons of half the species in two communities would require surveys at least 10-fold larger for each community.

Appl Environ Microbiol, 2002 Jun, 68(6), 2704 - 10
Immobilization of radionuclides and heavy metals through anaerobic bio-oxidation of Fe(II); Lack JG et al.; Adsorption of heavy metals and radionuclides (HMR) onto iron and manganese oxides has long been recognized as an important reaction for the immobilization of these compounds . However, in environments containing elevated concentrations of these HMR the adsorptive capacity of the iron and manganese oxides may well be exceeded, and the HMR can migrate as soluble compounds in aqueous systems . Here we demonstrate the potential of a bioremediative strategy for HMR stabilization in reducing environments based on the recently described anaerobic nitrate-dependent Fe(II) oxidation by Dechlorosoma species . Bio-oxidation of 10 mM Fe(II) and precipitation of Fe(III) oxides by these organisms resulted in rapid adsorption and removal of 55 microM uranium and 81 microM cobalt from solution . The adsorptive capacity of the biogenic Fe(III) oxides was lower than that of abiotically produced Fe(III) oxides (100 microM for both metals), which may have been a result of steric hindrance by the microbial cells on the iron oxide surfaces . The binding capacity of the biogenic oxides for different heavy metals was indirectly correlated to the atomic radius of the bound element . X-ray absorption spectroscopy indicated that the uranium was bound to the biogenically produced Fe(III) oxides as U(VI) and that the U(VI) formed bidentate and tridentate inner-sphere complexes with the Fe(III) oxide surfaces . Dechlorosoma suillum oxidation was specific for Fe(II), and the organism did not enzymatically oxidize U(IV) or Co(II) . Small amounts (less than 2.5 microM) of Cr(III) were reoxidized by D . suillum; however, this appeared to be inversely dependent on the initial concentration of the Cr(III) . The results of this study demonstrate the potential of this novel approach for stabilization and immobilization of HMR in the environment.

Appl Environ Microbiol, 2002 Jun, 68(6), 2683 - 9
Detection of microbial growth on polycyclic aromatic hydrocarbons in microtiter plates by using the respiration indicator WST-1; Johnsen AR et al.; We have developed a microtiter plate method for screening a large number of bacterial isolates for the ability to grow on different crystalline polycyclic aromatic hydrocarbons (PAHs) . Growth on PAHs cannot easily be determined with standard growth assays because of the very low aqueous solubility and bioavailability of the PAHs . Our microtiter plate assay utilizes a new water-soluble respiration indicator, WST-1 {4-{3-(4-iodophenyl)-2-(4-nitrophenyl)-2H-5-tetrazolio}-1,3-benzene disulfonate}, in combination with easily degradable carbon sources . PAH-mineralizing strains were grown on PAHs in microtiter plates for 7 to 10 days . The tetrazolium dye WST-1 was added after incubation . Dehydrogenases in growing cells reduced WST-1 to a water-soluble colored formazan, and the intensity of the color was a measure of the respiration rate . Addition of easily degradable carbon to the wells along with WST-1 resulted in a 3- to 40-fold increase in the absorbance of positive wells within 90 min, which made it possible to detect growth on fluorene, phenanthrene, anthracene, fluoranthene, and pyrene . Addition of the electron transport blocker sodium azide unexpectedly decreased formazan formation . The method was adapted for most-probable-number enumeration of PAH degraders in soil.

Environ Sci Technol, 2002 May 15, 36(10), 2205 - 12
Effect of exposure history on microbial herbicide degradation in an aerobic aquifer affected by a point source; Tuxen N et al.; The effects of in situ exposure to low concentrations (micrograms per liter) of herbicides on aerobic degradation of herbicides in aquifers were studied by laboratory batch experiments . Aquifer material and groundwater were collected from a point source with known exposure histories to the herbicides mecoprop (MCPP), dichlorprop, BAM, bentazone, isoproturon, and DNOC . Degradation of the phenoxy acids, mecoprop and dichlorprop, was observed in five of six sampling points from within the plume . Mecoprop was mineralized, and up to 70% was recovered as 14CO2 . DNOC was degraded in only two of six sampling points from within the plume, and neither BAM, bentazone, nor isoproturon was degraded in any sampling point . A linear correlation (R2 > or = 0.83) between pre-exposure and amount of herbicide degraded within 50 days was observed for the phenoxy acids, mecoprop and dichlorprop . An improved model fit was obtained from using Monod degradation kinetics compared to zero- and first-order degradation kinetics . An exponential correlation (R2 > or = 0.85) was also found between numbers of specific phenoxy acid degrading bacteria and pre-exposure . Combination of these results strongly indicates that the low concentration exposure to phenoxy acids in the aquifer resulted in the presence of acclimated microbial communities, illustrated bythe elevated numbers of specific degraders as well as the enhanced degradation capability . The findings support application of natural attenuation to remediate aerobic aquifers contaminated by phenoxy acids from point sources.

Adv Space Res, 2000, 26(12), 2029 - 40
Effects of solar UV-B radiation on aquatic ecosystems; Hader DP; Solar UV degrades dissolved organic carbon photolytically so that they can readily be taken up by bacterioplankton . On the other hand solar UV radiation inhibits bacterioplankton activity . Bacterioplankton productivity is far greater than previously thought and is comparable to phytoplankton primary productivity . According to the "microbial loop hypothesis," bacterioplankton is seen in the center of a food web, having a similar function to phytoplankton and protists . The penetration of UV and PAR into the water column can be measured . Marine waters show large temporal and regional differences in their concentrations of dissolved and particulate absorbing substances . A network of dosimeters (ELDONET) has been installed in Europe ranging from Abisko in Northern Sweden to Gran Canaria . Cyanobacteria are capable of fixing atmospheric nitrogen which is then made available to higher plants . The agricultural potential of cyanobacteria has been recognized as a biological fertilizer for wet soils such as in rice paddies . UV-B is known to impair processes such as growth, survival, pigmentation, motility, as well as the enzymes of nitrogen metabolism and CO2 fixation . The marine phytoplankton represents the single most important ecosystem on our planet and produces about the same biomass as all terrestrial ecosystems taken together . It is the base of the aquatic food chain and any changes in the size and composition of phytoplankton communities will directly affect food production for humans from marine sources . Another important role of marine phytoplankton is to serve as a sink for atmospheric carbon dioxide . Recent investigations have shown a large sensitivity of most phytoplankton organisms toward solar short-wavelength ultraviolet radiation (UV-B); even at ambient levels of UV-B radiation many organisms seem to be under UV stress . Because of their requirement for solar energy, the phytoplankton dwell in the top layers of the water column . In this near-surface position phytoplankton will be exposed to solar ultraviolet radiation . This radiation has been shown to affect growth, photosynthesis, nitrogen incorporation and enzyme activity . Other targets of solar UV irradiation are proteins and pigments involved in photosynthesis . Whether or not screening pigments can be induced in phytoplankton to effectively shield the organisms from excessive UV irradiation needs to be determined . Macroalgae show a distinct pattern of vertical distribution in their habitat . They have developed mechanisms to regulate their photosynthetic activity to adapt to the changing light regime and protect themselves from excessive radiation . A broad survey was carried out to understand photosynthesis in aquatic ecosystems and the different adaptation strategies to solar radiation of ecologically important species of green, red and brown algae from the North Sea, Baltic Sea, Mediterranean, Atlantic, polar and tropical oceans . Photoinhibition was quantified by oxygen exchange and by PAM (pulse amplitude modulated) fluorescence measurements based on transient changes of chlorophyll fluorescence . c2001 COSPAR Published by Elsevier Science Ltd . All rights reserved.

Microb Ecol, 2002 Apr, 43(3), 307 - 14 Epub 2002 Mar 05.
Changes in soil microbial community structure and function in an alpine dry meadow following spring snow melt; Lipson DA et al.; Previous work in an alpine dry meadow in the Front Range of the Rocky Mountains has shown that microbial biomass is high during winter and declines rapidly as snow melts in the spring, and that this decline is associated with changes in temperature regime and substrate availability . In this study we tested the hypothesis that the summer and winter microbial communities differ in function and composition . Shifts in species composition between pre- and post-snowmelt communities were detected using reciprocal hybridization of community DNA; DNA extracted from soils sampled at different times was significantly less homologous relative to spatial replicates sampled at the same time . Fungal/bacterial ratios, as measured by direct microscopic counts and by substrate-induced respiration experiments with specific inhibitors, were higher in winter soils . Specific activity of cellulase (absolute cellulase activity per unit microbial biomass C) was higher in the winter soils than in summer soils, while specific amylase activity was not different between winter and summer . Based on most-probable number measurements, the use of the phenolic compound vanillic acid was highest in the winter, while the use of the amino acid glycine was lowest in the winter . Winter and summer soil respiration responded differently to temperature; at 0 degrees C, winter soils respired at a higher proportion of the 22 degrees C rate than did summer soils.

Caries Res, 2002 Mar-Apr, 36(2), 129 - 35
Inhibition of secondary caries lesion progression using fluoride varnish; Fontana M et al.; The purpose of this study was to determine the efficacy of fluoride varnish (FV) in inhibiting progression of secondary caries (SC) . In a first experiment, human teeth, restored either with amalgam or resin composite, were exposed for 4 days to a microbial caries model . Half of each specimen was then painted with an acid-resistant nail varnish to maintain the baseline SC lesion . Specimens were then either treated with a FV (removed after 24 h) or not treated (control groups) prior to being exposed for 4 more days to the caries model . A second experiment was conducted to compare the effect that the varnish (with and without fluoride) had on SC development around amalgam . Confocal laser scanning microscopy data from these experiments suggested that the application of a FV to early, active SC lesions significantly slowed down their progression . Furthermore, the application of a placebo varnish showed a trend towards slowing down lesion progression, suggesting that the effect of FV on SC is not only due to its fluoride release .

Life Sci Space Res, 1965, 3, 105 - 19
Gulliver and Diogenes--exobiological antitheses; Levin GV et al.; Gulliver field test results in extreme natural environments are presented . A proposed new exobiology experiment, based on the detection of adenosinetriphosphate (ATP), is described with laboratory results . Significant responses were obtained from the Gulliver field tests in approximately one hour . Responses were even more pronounced when the radioactive medium was applied directly to the soil . In the new life detection experiment, the firefly bioluminescent reaction is used to assay for micro-gamma quantities of microbial ATP, a compound ubiquitous in terrestrial life . Gulliver and the ATP experiment, named Diogenes, represent complimentary antitheses in extraterrestrial life detection . The former is general and the latter specific . Theoretical considerations are proposed as guidelines for extraterrestrial life detection experiments.

Microb Ecol, 2000 Dec, 40(4), 317 - 329
The Microbial Food Web in the Recently Flooded Sep Reservoir: Diel Fluctuations in Bacterial Biomass and Metabolic Activity in Relation to Phytoplankton and Flagellate Grazers; Jugnia LB et al.; The spatial distribution of the bacterial biomass and production and of potential heterotrophic activity (PHA) were measured every 4 h between 23 July (10:00 h) and 25 July (10:00 h) 1997 in a recently flooded oligo-mesotrophic reservoir (the Sep Reservoir, Puy-de-Dome, France), in relation to temperature, the phytoplankton biomass and production, and the abundance of heterotrophic flagellates . The temperature varied slightly with time during the study, but the well-established thermal stratification agreed well with vertical distribution of the biological variables that were measured . Only the bacterial production and the PHA showed significant diel changes (t-test, p <0.05), with maxima at 18:00 h and minima at 02:00 h . A significant positive relation was found between bacterial abundance and that of heterotrophic flagellates, which, rather than being an association related to the thermal stratification of the water column, was considered to reflect a trophic relation between these two communities . A carbon balance analysis suggested that at least 30% of the C from primary production measured during the sampling period was used by bacteria, and that 42% of this secondary production, or 6% of the primary production, would be used for the development of the heterotrophic flagellates present . We conclude that the bacterioplankton forms, at least occasionally, an important source of carbon for higher trophic levels, and reject the hypothesis that bacterial production in the Sep Reservoir depends exclusively on organic matter of allochthonous origin.

Biochem Pharmacol, 2002 May 15, 63(10), 1901 - 10
Involvement of p38 mitogen-activated protein kinase in the induction of interleukin-12 p40 production in mouse macrophages by berberine, a benzodioxoloquinolizine alkaloid; Kang BY et al.; Interleukin (IL)-12 plays a pivotal role in the development of T helper type 1 (Th1)-immune response, which may have therapeutic effects on diseases associated with pathologic Th2 responses such as allergic disorders and asthma . In this study, we investigated the effects of berberine, a benzodioxoloquinolizine alkaloid with anti-microbial and anti-tumor activities, on the production of IL-12 p40, an inducible subunit of IL-12, in mouse macrophages . Berberine-induced IL-12 p40 production and activation of p38 mitogen-activated protein kinase (MAPK) in dose-dependent manners, which were significantly inhibited by p38 MAPK inhibitors and yohimbine, indicating that p38 MAPK and alpha(2)-adrenergic receptor were involved in the induction of IL-12 p40 production in mouse macrophages by berberine . Furthermore, berberine significantly enhanced IL-12 p40 production in mouse macrophages when combined with lipopolysaccharide, a well-known inducer of IL-12 production . These findings may explain some of the known biological effects of berberine and suggests berberine as an immunotherapeutic compound for induction of IL-12, which is potentially applicable for tumors, infectious disease, and airway inflammation.

Clin Exp Optom, 2002 May, 85(3), 127 - 40
Is there a question of safety with continuous wear?
Brennan NA.
The availability of silicone-containing hydrogel contact lenses (SCHCLs) has refocused attention on the risks associated with continuous wear (CW) . The major barrier to optometrists prescribing CW in Western societies is a perceived danger of microbial keratitis (MK) . This perception has been shaped largely by educators who have developed their opinions from case reports in the ophthalmic literature, sensationalist lay press reports and later epidemiological studies and from prominent physicians in tertiary referral centres, following an increased incidence of MK with extended wear (EW) of traditional hydrogel materials . The basis for the perceived lack of safety is the higher risk of MK with EW compared to daily wear and incidence figures that suggest an unacceptable level of MK in a population at risk, albeit a small risk on an individual basis . In this paper, I re-evaluate the validity of the previous data and challenge the conclusions regarding the nature of the risk with traditional hydrogel lens materials . Areas under scrutiny include diagnostic criteria, morbidity caused by different micro-organisms, potential bias in studies and reports, analysis of visual outcomes and cost to the community, and improvements over time in the understanding and handling of contact lens-related complications . Significant loss of vision with EW appears to be less frequent than is the common perception . When the risks are placed in the perspective of other data such as that for refractive surgery, the arguments against EW do not seem so compelling . The high oxygen transmissibility of SCHCLs may enable safe CW but a large-scale epidemiological study is needed to allay remaining doubts . Any such future studies should note the points outlined in this document.

Poult Sci, 2002 May, 81(5), 695 - 8
Comparison of eggshell surface microbial populations for in-line and off-line commercial egg processing facilities; Knape KD et al.; The objective of this project was to evaluate the aerobic plate counts (APC) of eggshells at in-line and off-line egg processing facilities at selected sites, throughout the processing procedure . Samples were collected from four sites in the processing plant and five time periods during the daily processing shift . Site 1 was from the conveyor system before the eggs passed through the washing system . Site 2 was after detergent wash but before sanitizer application . Site 3 was immediately after sanitizer treatment . Site 4 was immediately before packaging . Samples were collected from the sites at five equally spaced intervals beginning 15 min after the processing shift began and ending 15 min before the processing shift ended . At each sampling time, eggs were aseptically collected from each site and placed into sterile plastic bags containing 50 mL of PBS that was serially diluted immediately . The dilutions were plated on APC agar within 8 h of collection and were incubated at 37 C for 48 h . APC counts of in-line and off-line eggs were compared within time periods across sites . As the processing shift progressed, off-line APC counts were significantly higher than in-line counts at Site 1 . At Site 2, off-line APC counts were significantly higher than in-line counts for Periods 2 through 5 . At Site 3, off-line APC counts were significantly higher than in-line counts for Periods 2 through 5 . Site 4 off-line counts were significantly higher than in-line counts at all time periods.

Microb Ecol, 2001 Feb, 41(2), 83 - 89
The Microbial Logic behind the Prevalence of Incomplete Oxidation of Organic Compounds by Acetogenic Bacteria in Methanogenic Environments; Dolfing J; Microbial degradation of organic material in methanogenic ecosystems is a multistep process in which subsequent groups use the products of the first groups of organisms in the chain as substrates . The acetogenic bacteria in these systems produce both H2 and acetate . In the present minireview a thermodynamic approach is taken to evaluate the logic behind this duality . The evaluation shows that at the H2 partial pressures that usually occur in methanogenic ecosystems the acetogenic oxidation of known acetogenic substrates such as propionate, butyrate, and benzoate yields more energy than their complete oxidation to H2/CO2 . Also, H2 partial pressures needed to achieve complete hydrogenogenic oxidation of these acetogenic substrates would have to be so low that H2 would be virtually unavailable to the hydrogenotrophic bacteria, in casu the methanogens.

Microb Ecol, 2001 Feb, 41(4), 341 - 351
Contribution of the Earthworm Lumbricus rubellus (Annelida, Oligochaeta) to the Establishment of Plasmids in Soil Bacterial Communities; Thimm T et al.; The contribution of the earthworm Lumbricus rubellus in spreading plasmids from a nonindigenous bacterial species to the soil microbial community was studied with Escherichia coli strains as donor organisms . The selected donor strains harbored marker-gene tagged plasmids with different transfer properties and host ranges . Prototrophic benzoate degrading indigenous bacteria were analyzed as potential recipients . In filter-mating experiments, donor strains were mixed with bacterial cell consortia extracted from earthworm casts (feces) and incubated on nutrient agar at 28 degrees C . Transfer was detected with the broad host range IncP plasmid pRP4luc; with the IncQ plasmid, pSUP104luc, but only when it was present in a mobilizing donor strain; and with the transposon delivery vector pUTlux . No transfer was detected with the nonmobilizable pUCluc and the mobilizable pSUP202luc, both of narrow host range . In microcosm studies with E . coli inoculated soil incubated at 12 degrees C, transconjugants were only detected in casts of L . rubellus but not in bulk soil, indicating that the gut passage was a precondition for plasmid transfer . Plasmid pRP4luc was transferred at higher frequencies than detected in filter mating . Results of the filter matings were confirmed except that transfer of pUTlux could not be detected . The majority of transconjugants isolated in this study lost their acquired plasmid upon further cultivation . Stable transconjugants, however, were obtained and identified at the 16S rRNA gene level as members of the b- and g-subgroups of Proteobacteria . Incubation of E . coli and selected transconjugants in soil microcosms with L . rubellus demonstrated that the gut passage resulted in a slight but significant reduction of ingested cells . In contrast to the donor strains, however, the population sizes of transconjugants in bulk soil and in casts did not decrease over time . This demonstrated that the transferred plasmids had established themselves in the soil microbial community.

Med Clin (Barc), 2002 May 4, 118(16), 622 - 6
{Community-acquired pneumonia associated with influenza virus}; Mirete Ferrer JC et al.; BACKGROUND: Pneumonia is one of the most common complications of influenza infection . However, its characteristics are not well-known . Our aim was to assess the frequency of community-acquired pneumonia (CAP) associated with influenza virus and to determine its clinical and epidemiological characteristics . PATIENTS AND METHOD: A total of 240 patients with CAP were evaluated and cases with serological evidence of influenza virus infection were identified . Patients in whom there was no evidence of infection by other microbial agents were selected and defined as influenza virus infection-associated CAP (CAP-i) . Clinical and epidemiological features of CAP-i patients were compared with the rest of patients with CAP . RESULTS: A microbial diagnosis was achieved in 143 (59.6%) of 240 patients with CAP . In 12 cases (5%) there was serological evidence of infection by influenza A virus . In 8 patients no other respiratory pathogens were detected (CAP-i) . In a multivariate analysis, the presence of arthromyalgias (odds ratio {OR} = 30, 68; 95% confidence interval {CI}, 1-946), plasmatic sodium < 133 mEq/l (OR = 16.92; 95% CI, 1.48-193), bilateral infiltrates in chest X-ray (OR = 8.83; 95% CI, 1.35-57.6), diagnosis of CAP in January or February (OR = 5.60; 95% CI, 0.87-35.8) and blood neutrophil cell count >= 14,000/l, (OR = 5.23; 95% CI, 0.85-32) were all independently associated with CAP-i . The simultaneous presence of all these characteristics had a positive and negative predictive value of 95% and 99%, respectively, to differentiate CAP-i from other CAP . CONCLUSIONS: Influenza virus infection-associated CAP is uncommon . Some clinical and radiographic variables could differentiate CAP-i from other CAP . These parameters could also help identify patients who are more likely to benefit from specific antiviral therapy.

Inhal Toxicol, 2002 May, 14(5), 541 - 9
Fungal spores as such do not cause nasal inflammation in mold exposure; Roponen M et al.; The increased frequency of respiratory symptoms and diseases among sawmill workers has been linked to occupational exposure to airborne contaminants, especially to different fungi . Similar adverse health effects, together with elevated levels of inflammatory mediators in the nasal lavage (NAL) fluid, have been detected in people working in mold-damaged buildings . However, the indoor fungal spore concentrations in moldy houses are much lower than those in sawmills . To study the effect of fungal spores as such on the inflammatory markers in the NAL fluid, we conducted a similar study in sawmill workers who had an intense exposure to fungal spores . NAL was performed in 11 sawmill workers both during high occupational microbial exposure and during their vacation . Concentrations of nitric oxide (NO), tumor necrosis factor-alpha (TNFalpha), interleukin (IL)-4, IL-5, and IL-6 in NAL fluid were analyzed, and occupational exposure to inhalable dust, fungal spores, endotoxins and terpenes was confirmed by personal monitoring during the day of sampling . In addition, health data were collected with a questionnaire . Personal exposures to fungal spores varied from 2 x 10(5) spores/m(3) to 1.5 x 10(6) spores/m(3) (mean 7 x 10(5) spores/m(3)) . Concentrations of inhalable dust, endotoxins, and terpenes were relatively low . There were no differences between work and vacation in the concentrations of NO and proinflammatory cytokines in NAL fluid or in the reporting of symptoms, and the levels were lower than in workers at a moldy school building . However, the concentration of TNFalpha in the NAL fluid was positively correlated with the concentration of terpenes in the working environment (r =.768; p =.006) . These results show that microbial exposure as such does not invariably result in inflammatory changes detectable with the NAL method . We suggest that the type of microbial flora or microbial products in the occupational environment determines the proinflammatory potency of microbial exposure.

Cell Microbiol, 2002 May, 4(5), 297 - 303
TLR4-dependent lipopolysaccharide signalling in epithelial cells is independent of extracellular protease activity; Backhed F et al.; Epithelial cells are the first cells that encounter infecting bacteria and, as such, they have developed several mechanisms for microbial protection . We have shown previously that bladder epithelial cells express the lipopolysaccharide (LPS) receptor Toll-like receptor (TLR) 4 that enables a rapid cellular interleukin (IL)-8 response when exposed to Escherichia coli and LPS . TLR4 belongs to a family of receptors that was initially identified in Drosophila, in which Toll is required for the immune response against fungi . Fungal exposure activates a series of serine proteases that process the protein Spaetzle to a cytokine-like form that acts as a ligand for Toll . Here, we investigated whether a similar proteolytic cascade is required for human TLR activation . When screening a set of 18 protease inhibitors, three serine protease inhibitors (TPCK, TLCK and Pefabloc) were shown to inhibit LPS- and peptidoglycan-induced IL-8 production in TLR2- and TLR4-positive bladder epithelial cells . However, they were equally effective inhibitors of IL-1beta-induced signalling, indicating that their target(s) is/are located downstream of the TLRs . Further characterization showed that these inhibitors blocked I kappa B degradation but not phosphorylation in LPS-stimulated cells, which suggests that the serine protease inhibitors target the 26S proteasome . Identical results were obtained on LPS-stimulated monocytes . Based on these data, we find no evidence for the involvement of proteases upstream of TLRs in either epithelial cells or cells of the monocytic lineage.

J Periodontol, 2002 May, 73(5), 564 - 70
Treatment of periodontal disease in a patient with Ehlers-Danlos syndrome . A case report and literature review; Perez LA et al.; BACKGROUND: Ehlers-Danlos syndrome (EDS) designates a heterogeneous group of connective tissue disorders characterized by skin elasticity, tissue fragility, and chronic joint pain . Dental findings have been reported with some types of EDS . This case report describes the periodontal findings in a patient with a previously undiagnosed EDS type VIII . METHODS: Diagnostic aids utilized included microbial testing, histological examination, gingival crevicular fluid (GCF) analysis for the levels of C-telopeptide pyridinoline cross-links (ICTP), and genetic counseling . Periodontal treatment consisted of mechanical debridement and adjunctive antibiotic therapy . RESULTS: Genetic counseling and clinical presentation confirmed the diagnosis of EDS type VIII . Periodontal treatment led to marked clinical improvements and GCF levels of the bone resorptive marker ICTP were significantly reduced . The patient and her siblings are currently pursuing appropriate medical care and genetic counseling . CONCLUSION: Periodontal involvement may lead to the diagnosis of an underlying systemic condition . Identification of suspected etiological factors of periodontal disease may prove critical for the general well-being of some patients.

Mol Plant Microbe Interact, 2002 Apr, 15(4), 323 - 33
Pseudomonas lipodepsipeptides and fungal cell wall-degrading enzymes act synergistically in biological control; Fogliano V et al.; Pseudomonas syringae pv . syringae strain B359 secreted two main lipodepsipeptides (LDPs), syringomycin E (SRE) and syringopeptin 25A (SP25A), together with at least four types of cell wall-degrading enzymes (CWDEs) . In antifungal bioassays, the purified toxins SRE and SP25A interacted synergistically with chitinolytic and glucanolytic enzymes purified from the same bacterial strain or from the biocontrol fungus Trichoderma atroviride strain P1 . The synergism between LDPs and CWDEs occurred against all seven different fungal species tested and P . syringae itself, with a level dependent on the enzyme used to permeabilize the microbial cell wall . The antifungal activity of SP25A was much more increased by the CWDE action than was that of the smaller SRE, suggesting a stronger antifungal role for SP25A . In vivo biocontrol assays were performed by using P . syringae alone or in combination with T . atroviride, including a Trichoderma endochitinase knock-out mutant in place of the wild type and a chitinase-specific enzyme inhibitor . These experiments clearly indicate that the synergistic interaction LDPs-CWDEs is involved in the antagonistic mechanism of P . syringae, and they support the concept that a more effective disease control is given by the combined action of the two agents.

J Environ Qual, 2002 May-Jun, 31(3), 752 - 8
Rototillage, disking, and subsequent irrigation: effects on soil nitrogen dynamics, microbial biomass, and carbon dioxide efflux; Calderon FJ et al.; Spring and summer tillage are usually followed by irrigation before planting crops in California's summer-dry Mediterranean-type climate . Tillage treatments such as rototillage or disking are known to disturb the soil structure to different extents, but little is known about how the intensity of a tillage event and subsequent irrigation affect the microbial biomass, respiration, CO2 efflux, and mineral N of agricultural soils . We carried out an experiment with a Yolo silt loam (fine-silty, mixed, superactive, nonacid, thermic Mollic Xerofluvent) with two tilled treatments (rototillage and disked and rolled) and a nontilled control . The soil was subsequently sampled throughout a 17-d period . Nine days after tillage, all treatments were lightly sprinkler-irrigated to bring the soil water potential above -10 kPa . After tillage, the soil ammonium and nitrate content increased rapidly relative to the control with highest increases in the disked soil . Mineral N remained higher in the tilled treatments after irrigation . Rototillage and disking increased the CO2 efflux of the soil within 24 h of the disturbance . The increase was higher in the disked soil, which was more than three times the CO2 efflux of the control soil at 0.25 h after tillage . This effect may be due to degassing of dissolved CO2 since microbial respiration did not increase in tilled soils . Irrigation increased the CO2 efflux of all treatments but this was most pronounced in the control soil, which had an order of magnitude increase in CO2 efflux after irrigation . An ancillary experiment carried out under similar conditions but with more frequent sampling showed that increases in CO2 efflux after irrigation were accompanied by increases in soil respiration . This study shows that different tillage implements affect CO2 efflux, nitrate accumulation, and microbial activity, and thus have different effects on soil and atmospheric environmental quality.

J Environ Qual, 2002 May-Jun, 31(3), 1004 - 9
Kraft mill residues effects on Monterey pine growth and soil microbial activity; Jordan M et al.; The production of bleached Kraft pulp generates inorganic and organic residues that are usually deposited on the soil surface or land-filled . Studies conducted to address the impact of these wastes on the environment are scarce . In this work, Monterey pine (Pinus radiata D . Don), an important tree for pulping, was evaluated for germination and development under greenhouse conditions in forest soils exposed to solid residues of the cellulose industry using the Kraft process . Soils exposed to 10 to 60% ashes, 10 to 70% fly ashes, or 10 to 30% dregs allowed substantial seed germination and seedling growth . In contrast, soils exposed to low proportions of brown rejects, grits, or a mixture of all these residues were detrimental for germination, plant growth, or both . The strongest negative effect (no germination) was observed with as low as 10% grits . The changes in pH and/or water content caused by solid wastes did not correlate with detrimental effects observed in various soil-residue combinations . No significant changes in the microbial community of soils exposed to these solid residues were observed by determination of culturable counts, or by terminal-restriction fragment length polymorphism analysis of the microbial community DNA . The presence of organic residues did not affect the ability of the soil microbial community to remove typical pulp bleaching chloroaromatics . However, inorganic wastes strongly decreased the removal of such compounds.

Mikrobiologiia, 2002 Mar-Apr, 71(2), 272 - 6
{Coupling of microbial processes of methane and ammonium oxidation in soils.}; Novikov VV et al.; The effect of ammonium ions on the activity of methane oxidation in soils was studied . The degree of inhibition of the methanotrophic activity in the presence of ammonium in the soil solution was quantitatively assessed as dependent on ammonium concentration and the properties of different types of soils of the European part of Russia.

Mikrobiologiia, 2002 Mar-Apr, 71(2), 230 - 6
{Phylogenetic diversity of the archaeal component in microbial mats on coral-like structures associated with methane seeps in the Black Sea}; Turova TP et al.; With the use of molecular ecology methods, the archaea component of microbial mats on coral-like structures associated with methane seeps occurring at a depth of about 200 m in the Black Sea was investigated without the isolation of pure cultures . Using archaea-specific 16S rRNA-targeted oligonucleotide primes, long fragments of genes were amplified, cloned, and sequenced and their phylogenetic analysis was carried out . It was shown that archaea in microbial mats on coral-like structures are represented by two dominant phylotypes that belong to the kingdoms Crenarchaeota and Euryarchaeota and are not specifically related to any described archaea species . The possible role of the revealed archaea in the process of anaerobic methane oxidation is discussed.

Khirurgiia (Sofiia), 2001, 57(3-4), 13 - 7
{Changing susceptibility patterns of surgical site infection pathogens after the introduction of modern perioperative chemotherapy in the emergency surgery clinic}; Tonev D et al.; 993 surgical site infection aerobic pathogens are isolated over a six-year period (I.1994-I.2000) by the Microbiology Laboratory at University Hospital "Tzaritza Joana" . 224 (22.6%) of them are isolated from patients undergoing abdominal surgery in the Emergency Surgery Clinic . The period covers 3 years before the introduction of current single-dose perioperative prophylaxis (i.e . under the conditions of long-term one) as well as the next 3 years following its introduction in the Emergency Surgery Clinic . The changes of pathogens susceptibility patterns to single-dose drug schemes in both hospital elective abdominal surgery and emergency surgery clinics are followed during the whole period . Our microbial susceptibility data support the ecological expedience of single-dose approach categorically.

Microb Ecol, 2001 Aug, 42(2), 177 - 185
Small-Scale Distribution of Bacteria, Enzymatic Activities, and Organic Matter in Coastal Sediments; Danovaro R et al.; The small-scale distribution of several structural (bacterial abundance, phytopigment, total and soluble protein, and carbohydrate content) and functional ecological variables (enzymatic activities, frequency of dividing cells) was investigated in coastal sediments during a spring bloom . For bacterial abundance, enzymatic activity, and organic matter determinations, samples were collected at 5-m depth from a sediment surface delimited by a 42 x 42-cm frame, divided into 49 squares . In order to test the influence of the bottom microtopography on the investigated variables, the size of this frame was defined to cover the distance between two subsequent ripples . As indicated by Fisher's index, benthic bacteria, enzymatic activities, proteins, carbohydrates, and their soluble fractions exhibited an aggregate distribution . Sampling size (i.e., sample unit of 36 cm2) was appropriate for all variables, except for chlorophyll a and frequency of dividing cells that displayed a contagious distribution . To estimate the reliability of the current sampling strategy, we compared the mean values from three randomly selected sample units with the average value of the entire sediment surface (i.e., 49 samples) . For all variables reported in this study, the use of three replicates was representative of the mean values of the sampled area with a confidence limit within +/-20% . Bacterial population sizes did not correlate with their potential food sources (e.g., phytopigments, proteins, and carbohydrates), or with enzymatic activities, suggesting the presence of possible time lags between organic inputs and microbial response . Chlorophyll a during the spring bloom displayed much higher concentrations than phaeopigments and correlated with carbohydrates . Chlorophyll a distribution was autocorrelated and displayed a large patch size (1,134 cm2) . Phaeopigments and proteins accumulated in the central depression of the ripple-mark structure, apparently depending upon a passive accumulation due to the reduced current action . In contrast, microphytobenthic biomass and bacterial numbers were highest in the two opposite ripples, suggesting that different driving forces operate selectively on the living components.

Microb Ecol, 2001 Aug, 42(2), 159 - 167
Weak Coupling between Heterotrophic Nanoflagellates and Bacteria in a Eutrophic Freshwater Environment; Wieltschnig C et al.; In a study on the dynamics and trophic role of the heterotrophic nanoflagellate (HNAN) assemblage in the microbial food web of a eutrophic oxbow lake abundances, biomass, and production rates of HNAN and their potential prey organisms, namely heterotrophic bacteria and autotrophic picoplankton, were monitored for a period of 2 years . No coupling between HNAN abundance and biomass and the abundance and biomass of their picoplanktonic prey was observed for the investigation period . The ratio of heterotrophic bacterial to HNAN abundance ranged from 2.2 x 103 to 8.6 x 103 (mean: 4.2 x 103 +/- 1.8 x 103) . HNAN carbon consumption could account for only 10% to 40% of bacterial secondary production . The lack of coupling between HNAN and their potential prey and the low HNAN abundance relative to bacterial abundance suggested (a) that HNAN grazing was an insignificant factor in the regulation of bacterial abundance and (b) that HNAN abundance was regulated by predation rather than by prey abundance . This hypothesis was supported by the fact that HNAN growth rates were high (in the range of 0.45 d-1 to 1.00 d-1 during spring and summer, yearly mean: 0.52 d-1), and only weakly correlated with prey abundance and biomass . The results indicated strong top-down control of HNAN and consequently a weak coupling of HNAN and picoplankton in the investigated eutrophic freshwater environment.

Microb Ecol, 2001 Oct, 42(3), 446 - 457
Aquatic Actinomycete-Fungal Interactions and Their Effects on Organic Matter Decomposition: A Microcosm Study; Wohl DL et al.; The role of fungi in the decomposition of organic matter in streams has been well examined, although the role of bacterial antagonists in such processes has gained little attention . To examine bacterial-fungal interactions, experiments involving pairwise combinations of four actinomycete isolates (A1+ and A2+ could remove chitin from chitin-containing media, and A1? and A2? could not) and two fungal isolates (F+ a true fungus, F? an oomycote) were conducted . For each bacterial-fungal combination, 250-ml microcosms were sampled at 8 day intervals for 32 days . Microbial biomass and organic matter, as well as the activities of five extracellular enzymes, were measured . Each experiment consisted of a control group and four treatment groups . Controls comprised sterilized stream water and macrophytes . The first treatment was inoculated with only actinomycetes (~103 cells ml-1), the second treatment was inoculated with only fungi (~102 cells ml-1), the third group was inoculated simultaneously with actinomycetes and fungi, and the fourth group was inoculated with actinomycetes 2 days after fungal establishment . For all combinations, the lowest rates of organic matter decomposition were expected in the controls, as a result of only physical degradation . In contrast, the greatest rates of organic matter decomposition were predicted in treatments inoculated with F+ 2 days prior to A1? or A2? . Greater than 50% of the organic matter was decomposed in each of the fungal treatments . Fungal-actinomycete interactions resulted in reduced fungal biomass relative to the fungal-only treatments . However, when inoculated 2 days apart, combinations of F? and actinomycetes resulted in enhanced rates of organic matter decomposition, as well as greater levels of extracellular enzyme activities . These results demonstrate that actinomycete-fungal interactions and their colonization dynamics affect the accumulation of biomass, extracellular enzyme activities, and rates of organic matter decomposition.

Microb Ecol, 2001 Oct, 42(3), 427 - 437
In Situ Assessment on the Physiological State of Purple and Green Sulfur Bacteria through the Analyses of Pigment and 5S rRNA Content; Casamayor EO et al.; Time-depth distribution of the microbial anaerobic assemblage of Lake Ciso was analyzed by microscopy, pigment composition, and electrophoretic analysis of 5S rRNAs . Purple (Amoebobacter-like and Thiocystis minor-like cells) and green (Chlorobium-like) sulfur bacteria were very abundant . Both groups coexisted in depth and in time despite the fact that they compete for the same natural resources (e.g., light and sulfide) . Cell abundance, group-specific pigment content, and group-specific 5S rRNA content did not change in parallel with depth . This was due to variations in the specific content of both RNA and pigments . Specific content of RNA was systematically higher in purple than in green sulfur bacteria . The latter, in turn, displayed a much higher pigment content . Specific content of both RNA and pigments changed with depth and time . Analysis of tRNA band patterns indicated no changes in the populations forming the assemblage . Changes in specific contents, therefore, were the result of physiological adaptations of the populations already present in the system . We concluded that each group of bacteria showed differential adaptations in both RNA and pigment content, and that the specific contents measured were good indicators of the physiological status of these bacteria in situ . The higher content of RNA in purple sulfur bacteria indicates that these organisms are the main contributors to anaerobic carbon fixation and sulfide oxidation processes in Lake Ciso.

Microb Ecol, 2001 Oct, 42(3), 248 - 255
Spatial Patterns of Soil Microbial Communities in a Norway Spruce (Picea abies) Plantation; Wilkinson SC et al.; The phospholipid fatty acid (PLFA) profiles of soil microbial communities were determined in relation to the patterns of tree cover in a mature Norway spruce plantation . Replicate samples of the surface organic layers were taken close to the trunk, at 1 m and at 2 m (under the edge of the canopy) beneath five trees . Samples were analyzed for standard PLFAs to assess the initial composition of the microbial communities . Replicate samples were then incubated under constant or fluctuating moisture conditions for 30 d to test the hypothesis that the patterns of microbial community structure (or its physiological state) might be determined by biophysical conditions under the tree canopies . The PLFA profiles near the trunks and at 2 m were similar, but samples taken 1 m from the bases of the trees contained lower concentrations of polyunsaturated (fungal) and monounsaturated PLFAs, and higher concentrations of saturated PLFAs . These differences in PLFA profiles were maintained during laboratory incubation under a regime of drying and wetting cycles, but there was some evidence of convergence in community structure under constant moisture conditions resulting from significant increases and decreases in specific bacterial PLFA concentrations . There were no effects of either moisture treatment on fungal PLFA concentrations . It is concluded that variation in the soil biophysical environment beneath the tree canopies resulted in the differentiation of spatially defined bacterial communities that were tolerant of moisture stress . The anomaly that differences in community structure were largest at an intermediate position of 1 m between the trunk and below the canopy edge was not explained but may relate to tree root distribution.

Microb Ecol, 2001 Oct, 42(3), 217 - 227
Size Selective Feeding in Cyclidium glaucoma (Ciliophora, Scuticociliatida) and Its Effects on Bacterial Community Structure: A Study from a Continuous Cultivation System; Posch T et al.; Three aspects of size selective feeding by the scuticociliate Cyclidium glaucoma were studied in continuous cultivation systems . Firstly, grazing-induced changes in abundance, biomass, and size structure of a bacterial community were investigated . Secondly, we studied possible grazing-protection mechanisms of bacteria as a response to permanent presence of the predator . And finally, we were looking for potential feedback mechanisms within this predator-prey relationship, i.e., how the ciliate population reacted to a changed, more grazing-protected bacterial community . The first stage of the cultivation system consisted of the alga Cryptomonas sp . and the accompanying mixed bacterial community . These organisms were transferred to two second stage vessels, a control stage without ciliates and a second one inoculated with C . glaucoma . After the first week, the abundance of bacteria in the latter decreased by 60% and remained stable until the end of the experiment (65 d), whereas bacterial biomass was less affected (393 mg C L-1 during days 0-7, 281 mg C L-1 afterwards) . The mean bacterial cell volume doubled from 0.089 mm3 to 0.167 mm3, which was mainly due to increasing cell widths . During the whole investigation period formation of colonies or filaments was not observed, but we found a clear feedback of ciliates on bacterial size . An increase in bacterial cell volume was always followed by a decline of the predator population, resulting in a yet undescribed type of microbial predator-prey relation . Literature and our own data on the optimal food size range grazed by C . glaucoma showed that bacterial cell width rather than length was responsible for that observed phenomenon . Finally, we suggest that uptake rates of spherical latex beads give only limited information on truly ingestible prey volumes and that prey geometry should be considered in future studies on size selective feeding of protists.

Microb Ecol, 2001 Dec, 42(4), 483 - 494
The Use of Whole-Cell Biosensors to Detect and Quantify Compounds or Conditions Affecting Biological Systems; Hansen LH et al.; A new and promising technique in microbial ecology and environmental biology is the use of whole-cell bacterial biosensors . This minireview describes the use of such biosensors for detection and quantification of various compounds and other conditions affecting bacterial expression of different genes . Three types of biosensors (nonspecific, stress-induced, and specific biosensors) are described including their use in different environments . We present tables of published biosensors, including gene fusions, host organisms, and environments in which they are used . We here describe the use of different reporter genes in the construction of biosensors and discuss their use as tools for monitoring the bioavailability of pollutants and their potential use in studying microbial ecology in general.

Arch Otolaryngol Head Neck Surg, 2002 May, 128(5), 561 - 6
The impact of atopy on neutrophil activity in middle ear effusion from children and adults with chronic otitis media; Hurst DS et al.; OBJECTIVE: To identify the relationship of neutrophil activity to allergy as reflected by the level of myeloperoxidase (MPO) in ears of atopic patients with chronic otitis media with effusion (OME) by objective testing . DESIGN: Evidence of neutrophils was measured in the effusion of atopic patients with chronic OME . Atopy was determined by intradermal and/or in vitro testing of allergic reaction to 10 inhalants, 2 molds, and 5 foods . SUBJECTS: Effusion MPO was measured prospectively in 138 ears from 106 consecutive patients with chronic OME . RESULTS: A total of 86 (81%) of 106 patients with OME tested atopic by in vitro or in vivo testing . Excluding 36 ears with purulence, the mean MPO level was 3132 microg/L in 84 atopic vs 142 microg/L in 18 nonatopic ears (P<.001) . A total of 78 (90%) of 87 patients with OME were atopic . CONCLUSIONS: The surprising finding of marked elevation of effusion MPO in atopic patients but very low levels in nonatopic patients (P < .001) suggests that atopy may contribute to elevated levels of neutrophil activity in OME . An atopic patient may respond differently from a nonatopic one to the microbial or viral products of acute inflammation owing to the presence of primed inflammatory cells . This study provides confirmation on a cellular level that neutrophils are an integral part of the inflammatory process in OME to a disproportionate degree among atopic patients.

Microb Ecol, 2002 Mar, 43(2), 225 - 31 Epub 2002 Feb 08.
Lysogeny and lytic viral production during a bloom of the cyanobacterium Synechococcus spp; Ortmann AC et al.; Lytic viral production and lysogeny were investigated in cyanobacteria and heterotrophic bacteria during a bloom of Synechococcus spp . in a pristine fjord in British Columbia, Canada . Triplicate seawater samples were incubated with and without mitomycin C and the abundances of heterotrophic bacteria, cyanobacteria, total viruses and infectious cyanophage were followed over 24 h . Addition of mitomycin C led to increases in total viral abundance as well as the abundance of cyanophages infecting Synechococcus strain DC2 . Given typical estimates of burst size, these increases were consistent with 80% of the heterotrophic bacteria and 0.6% of Synechococcus cells being inducible by the addition of mitomycin C . This is the highest percentage of lysogens reported for a natural microbial community and demonstrates induction in a marine Synechococcus population . It is likely that the cyanophage production following the addition of mitomycin C was much higher than that titered against a single strain of Synechococcus; hence this estimate is a minimum . In untreated seawater samples, lytic viral production was estimated to remove ca . 27% of the gross heterotrophic bacterial production, and a minimum of 1.0% of the gross cyanobacterial production . Our results demonstrate very high levels of lysogeny in the heterotrophic bacterial community, outside of an oligotrophic environment, and the presence of inducible lysogens in Synechococcus spp . during a naturally occurring bloom . These data emphasize the need for further examination of the factors influencing lytic and lysogenic viral infection in natural microbial communities.

J Immunol, 2002 Jun 1, 168(11), 5424 - 33
Distinct clonal Ig diversification patterns in young appendix compared to antigen-specific splenic clones; Sehgal D et al.; The young rabbit appendix is a dynamic site for primary B cell repertoire development . To study diversification patterns during clonal expansion, we collected single appendix B cells from 3- to 9-wk-old rabbits and sequenced rearranged H and L chain genes . Single cells obtained by hydraulic micromanipulation or laser capture microdissection were lysed, PCR amplified, and products directly sequenced . Gene conversion-like changes occurred in rearranged H and L chain sequences by 3-4 wk of age . Somatic mutations were found in the D regions that lack known conversion donors and probably also occurred in the V genes . A few small sets of clonally related appendix B cells were found at 3-5 wk; by 5.5 wk, some larger clones were recovered . The diversification patterns in the clones from appendix were strikingly different from those found previously in splenic germinal centers where an immunizing Ag was driving the expansion and selection process toward high affinity . Clonally related appendix B cells developed different amino acid sequences in each complementarity-determining region (CDR) including CDR3, whereas dominant clones from spleen underwent few changes in CDR3 . The variety of combining sites generated by diversification within individual clones suggests that at least some clonal expansion and selection, known to require normal gut flora, may be driven through indirect effects of microbial components rather than solely by their recognition as specific foreign Ags . This diversity of combining sites within B cell clones supports the proposed role of appendix in generating the preimmune repertoire.

Ann N Y Acad Sci, 2002 May, 964, 13 - 45
Current understanding of gastrointestinal immunoregulation and its relation to food allergy; Brandtzaeg PE; Tolerance to food antigens induced via the gut ("oral tolerance") appears to be a rather robust adaptive immune mechanism . However, the neonatal period is particularly critical in terms of mucosal defense, with regard to infections and priming for allergic disease . This is so because the intestinal barrier function provided by secretory antibodies, as well as the immunoregulatory network, is poorly developed for a variable period after birth . Notably, the postnatal development of mucosal immune homeostasis depends on the establishment of a normal commensal microbial flora and also on adequate timing and dose of dietary antigens when first introduced . In this context, breastfeeding appears to exert both shielding and positive regulatory effects . Altogether, the intestinal immune system normally seems rather fit for tolerance induction against innocuous antigens because most children with food allergy "outgrow" their problems, whereas airway allergy tends to persist.

Curr Issues Intest Microbiol, 2002 Mar, 3(1), 15 - 22
The development of gut immune responses and gut microbiota: effects of probiotics in prevention and treatment of allergic disease; Rautava S et al.; The infant's immature intestinal immune system develops as it comes into contact with dietary and microbial antigens in the gut . The evolving indigenous intestinal microbiota have a significant impact on the developing immune system and there is accumulating evidence indicating that an intimate interaction between gut microbiota and host defence mechanisms is mandatory for the development and maintenance of a balance between tolerance to innocuous antigens and capability of mounting an inflammatory response towards potential pathogens . Disturbances in the mucosal immune system are reflected in the composition of the gut microbiota and vice versa . Distinctive alterations in the composition of the gut microbiota appear to precede the manifestation of atopic disease, which suggests a role for the interaction between the intestinal immune system and specific strains of the microbiota in the pathogenesis of allergic disorders . The administration of probiotics, strains of bacteria from the healthy human gut microbiota, have been shown to stimulate antiinflammatory, tolerogenic immune responses, the lack of which has been implied in the development of atopic disorders . Thus probiotics may prove beneficial in the prevention and alleviation of allergic disease.

J Microencapsul, 2002 May-Jun, 19(3), 347 - 56
Effects of double encapsulation and coating on synthetic seed conversion in M.26 apple rootstock; Micheli M et al.; Encapsulated vitro-derived apical buds of M.26 apple rootstock (Malus pumila Mill) can be employed for the formation of the synthetic seed . Satisfactory levels of conversion (plantlets from synthetic seed) can be achieved if there are adequate (i) rooting induction treatment, (ii) protocol of encapsulation, and (iii) nutritive and environmental conditions . For capsule manufacturing, sodium alginate is largely used; however, this is excessively permeable with loss of the nutritive substances (artificial endosperm) and/or dehydration risks during conservation and transport causing detrimental effects on the synthetic seed conversion and on the plantlet's growth . In order to overcome these problems, two experiments were carried out comparing simple encapsulation in alginate with double encapsulation, and with encapsulation-coating procedures . The presence of a second layer of alginate (double encapsulation) and of a thin external coating layer over the alginate (encapsulation-coating) did not show any detrimental effects on viability, sprouting and regrowth of the encapsulated microcuttings . Satisfactory conversion (70%) was reached with the encapsulation-coating procedure, whereas the double and simple encapsulation converted less than 40% of the synthetic seed . The effect of the addition to the capsule of an anti-microbial substance (Plant Preservative Mixture - PPM) was examined: it did not compromise the conversion of the encapsulated microcuttings sown in ex-vitro non-aseptic conditions.

Cell Mol Life Sci, 2002 Apr, 59(4), 575 - 88
Microbial cycling of volatile organic sulfur compounds; Lomans BP et al.; Microbial cycling of volatile organic sulfur compounds (VOSCs), especially dimethyl sulfide (DMS) and methanethiol (MT), is intensively studied because these compounds play an important role in the processes of global warming, acid precipitation, and the global sulfur cycle . VOSC concentrations in freshwater sediments are low due to the balance between the formation and degradation of these compounds . These reactions occur for the greater part at the oxic/anoxic interphase of sediment and water column . In contrast to marine ecosystems, where dimethylsulfoniopropionate is the main precursor of MT and DMS, in freshwater ecosystems, VOSCs are formed mainly by methylation of sulfide and to a lesser extent from the degradation of S-containing amino acids . One of the major routes for DMS and MT formation through sulfide methylation is anaerobic O-demethylation of methoxylated aromatic compounds . Inhibition studies have revealed that the major part of the endogenously produced MT and DMS is degraded anaerobically by methanogens . The major bacterial groups involved in formation and consumption of VOSCs are described.

Cleve Clin J Med, 2002 May, 69(5), 419 - 24
The new American diet and the changing face of foodborne illness; Taege AJ; Pathogens responsible for foodborne illness are changing, owing to changes in the American diet as well as in food production and distribution . Microbial adaptations to heat, acid, cold, and antibiotics have made food safety a challenging task . This article reviews the common pathogens, their sources, and treatment.

Appl Biochem Biotechnol, 2002 Spring, 98-100, 977 - 86
Esterification activity and stability of Candida rugosa lipase immobilized into chitosan; Pereira EB et al.; Microbial lipase from Candida rugosa immobilized into porous chitosan beads was tested for esterification selectivity with butanol and different organic acids (C2-C12), and butyric acid and different aliphatic alcohols (C2-C10) . After 24 h, the acids tested achieved conversions of about 40-45% . Acetic acid was the only exception, and in this case butanol was not consumed . Different alcohols led to butyric acid conversions >40%, except for ethanol, in which case butyric acid was converted only 26% . The system's butanol and butyric acid were selected for a detailed study by employing an experimental design . The influence of temperature, initial catalyst concentration, and acid:alcohol molar ratio on the formation of butyl butyrate was simultaneously investigated, employing a 2(3) full factorial design . The range studied was 37-50 degrees C for temperature (X1), 1.25-2.5% (w/v) for the catalyst concentration (X2), and 1 and 2 for the acid:alcohol molar ratio (X3) . Catalyst concentration (X2) was found to be the most significant factor and its influence was positive . Maximum ester yield (83%) could be obtained when working at the lowest level for temperature (37 degrees C), highest level for lipase concentration (2.5% {w/v}), and center level of acid:alcohol molar ratio (1.5) . The immobilized lipase was also used repeatedly in batch esterification reactions of butanol with butyric acid, revealing a half-life of 86 h.

Appl Biochem Biotechnol, 2002 Spring, 98-100, 577 - 89
Utilization of xylitol dehydrogenase in a combined microbial/enzymatic process for production of xylitol from D-glucose; Mayer G et al.; The production of xylitol from D-glucose occurs through a three-step process in which D-arabitol and D-xylulose are formed as the first and second intermediate product, respectively, and both are obtained via microbial bioconversion reactions . Catalytic hydrogenation of D-xylulose yields xylitol; however, it is contaminated with D-arabitol . The aim of this study was to increase the stereoselectivity of the D-xylulose reduction step by using enzymatic catalysis . Recombinant xylitol dehydrogenase from the yeast Galactocandida mastotermitis was employed to catalyze xylitol formation from D-xylulose in an NADH-dependent reaction, and coenzyme regeneration was achieved by means of formate dehydrogenase-catalyzed oxidation of formate into carbon dioxide . The xylitol yield from D-xylulose was close to 100% . Optimal productivity was found for initial coenzyme concentrations of between 0.5 and 0.75 mM . In the presence of 0.30 M (45 g/L) D-xylulose and 2000 U/L of both dehydrogenases, exhaustive substrate turnover was achieved typically in a 4-h reaction time . The enzymes were recovered after the reaction in yields of approx 90% by means of ultrafiltration and could be reused for up to six cycles of D-xylulose reduction . The advantages of incorporating the enzyme-catalyzed step in a process for producing xylitol from D-glucose are discussed, and strategies for downstream processing are proposed by which the observed coenzyme turnover number of approx 600 could be increased significantly.

Appl Biochem Biotechnol, 2002 Spring, 98-100, 395 - 402
Foam fractionation of a dilute solution of bovine lactoferrin; Noel J et al.; Lactoferrin (Lf), a protein found in human and bovine milk, tears, blood, and other secretory fluids, has been used to prevent infection from potential microbial pathogens by its ability to bind with iron (Fe3+) . Currently, bovine lactoferrin can be purified from milk using ion exchange resin, which is a costly procedure making lactoferrin expensive . The purpose of this work was to investigate a low-cost foam fractionation process as the first step in separating lactoferrin from milk.

J Mol Med, 2002 May, 80(5), 290 - 300 Epub 2002 Apr 11.
Regulation of autoimmune disease by natural killer T cells; Sharif S et al.; Natural killer T (NKT) cells express phenotypic characteristics shared by conventional natural killer cells and T cells, and reside in several primary and secondary lymphoid as well as nonlymphoid organs . Although these cells possess important effector functions in immunity against cancer and microbial pathogens, their immunoregulatory function has received much recent attention . There is convincing evidence to suggest a regulatory role for these cells in the control of susceptibility to autoimmune disease . NKT cells are reduced in number and function in autoimmune disease prone mice and humans . Studies conducted in mice have shown that transfer of NKT cells to disease-susceptible recipients prevents the development of autoimmune disease . The recent discovery that alpha-galactosylceramide, a glycolipid, can specifically target NKT cells expressing the invariant T cell receptor (TCR) to proliferate and produce an array of regulatory cytokines and chemokines has generated considerable interest to utilize these cells as targets of new therapeutic interventions for the immunoregulation of autoimmune disease

J Anim Sci, 2002 May, 80(5), 1335 - 43
NutriDense and waxy corn hybrids: effects on site and extent of disappearance of nutrients in sheep; Akay V et al.; Six Suffolk wether lambs (40.9+/-1.05 kg) surgically fitted with ruminal and double-L-shaped duodenal and ileal cannulas were used in a 3 x 6 Latin rectangle design to investigate the effects of three corn hybrids on site and extent of disappearance of nutrients and rumen characteristics . Treatments were 1) a conventional yellow dent corn (CC) diet, 2) a NutriDense corn (NC) diet, and 3) a waxy corn (WC) diet . Diets consisted of 43.9% cracked corn grain, 39.1% cottonseed hulls, 15.3% soybean meal, 1.49% vitamin and mineral supplement, and 0.21% chromic oxide (DM basis) . Lambs were fed twice daily at 1.8 x NEm requirement . Ruminal pH, fluid dilution rate, volume, NH3 N, and total VFA concentrations, as well as molar proportions of isobutyrate, butyrate, and valerate, were similar (P > 0.10) among dietary treatments . Apparent and true OM disappearances (g/d and percentage of OM intake) from the stomach were similar (P > 0.10) among dietary treatments . Apparent OM disappearance (percentage of duodenal OM flow) from the small intestine was higher (P < 0.05) for the WC than for the NC treatment . Apparent total tract OM disappearance (percentage of OM intake) was also similar (P > 0.10) among dietary treatments . Total apparent and true starch disappearances (g/d) from the stomach were higher (P < 0.05) for the WC diet than for the CC and NC diets . However, apparent and true starch disappearances from stomach as percentage of starch intake were higher (P < 0.05) for the WC diet than for the CC diet . Starch disappearance (g/d) from the small intestine was higher (P < 0.05) for the CC diet than for the WC diet; however, apparent starch disappearance (percentages of duodenal starch flow) from the small intestine was higher (P < 0.05) for the WC diet than for the CC diet . Duodenal flows of total N, bacterial N, NH3 N, and non-NH3 nonbacterial N (g/d) and efficiencies of bacterial protein production (g of bacterial N/kg of true or apparent OM disappearing in the stomach) were similar (P > 0.10) among dietary treatments . Apparent and true N disappearance from stomach (g/d) and apparent total tract N disappearance (percentage of N intake) were also similar (P > 0.10) among dietary treatments . Total N disappearance from the hindgut was -0.81, -1.06, and -1.46 g/d for CC, NC, and WC, respectively, and was different (P < 0.05) between CC and WC diets . Results indicated that higher ruminal starch disappearance in WC did not increase microbial N production or efficiency when compared to CC.

Curr Biol, 2002 May 14, 12(10), R357 - 9
Microbial killing: oxidants, proteases and ions; Harrison RE et al.; There is accumulating evidence that two aspects of the innate immune response, the respiratory burst and secretion of proteases, are intimately intertwined . A recent study suggests that K(+) may be the missing link . Is it time to merge signal transduction with biophysics?

Curr Biol, 2002 May 14, 12(10), R352 - 4
Plant defence: a new weapon in the arsenal; Gray WM; Plants have evolved intricate defence mechanisms to cope with the wide array of microbial pathogens they encounter . The identification of Sgt1 as an essential component of R gene-mediated disease resistance suggests that the ubiquitin protein degradation pathway plays an important role in plant defence.

Bull Tokyo Dent Coll, 2002 Feb, 43(1), 7 - 12
SEM observations of resected root canal ends following apicoectomy; Furusawa M et al.; The purpose of this study was to examine the apical foramen of root apices extracted during apicotomies . A total of 25 teeth extracted from 25 patients admitted to the Department of Conservative Dentistry at Tokyo Dental College's Chiba Hospital were used for the study . All patients were between 22 to 56 years of age at the time of the study, and each of the 25 cases was determined clinically on radiographs to be chronic apical suppurative periodontitis . Microsurgery was performed on all cases, and the extracted root apices were then observed using SEM . The results demonstrated a wide opening, greater than 350 microns as measured along the major axis, of the apical foramen in 80% of the cases . Various characteristics indicative of resorption were observed around the apical foramen . These features included those believed to have been caused by overinstrumentation during root canal treatment as well as irregularly shaped areas presumed to be apical lesions that had enlarged and eroded . We observed a high frequency of manifestations of cementum resorption surrounding the root apices of teeth with apical lesions . Furthermore, we concluded that in the majority of cases in the present study, due to the fact that the apical foramen exceeded normal opening dimensions as a result of overinstrumentation during root canal treatment or resorption around the root apex, prolongation of the lesions had occurred in response to direct contact of microbial infectious matter and tissues surrounding the root apex over a large area . The above finding suggested that, in cases in which the apical foramen is destroyed through overinstrumentation larger than #35 or in which the apical foramen opens up to dimensions greater than 350 microns due to pathologic resorption, surgical intervention may be indicated . On the other hand, in 64% of the cases, an accessory canal was observed in the root apical lesion . Based on this observation, the presence of an accessory canal in the root apex may contribute to some degree to the prolongation of the lesion.

Curr Opin Pediatr, 2002 Jun, 14(3), 334 - 7
Infections and asthma in children; Montalbano MM et al.; The temporal association of acute asthma exacerbations in children with viral infections such as rhinovirus, respiratory syncytial virus, and parainfluenza has been known for many years . Recently, the contributions of infections to the pathophysiology of asthma have been expanded beyond disease exacerbation to include disease inception, chronicity, and even prevention . Respiratory syncytial virus has been implicated in asthma inception, while Chlamydia pneumoniae, Mycoplasma pneumoniae, and latent adenovirus infections have been correlated with asthma chronicity . Measles, hepatitis A, and tuberculosis have been associated with a decreased incidence of asthma, implying a contribution to disease prevention . The following review will briefly highlight the relationships between various microbial infections and the pathophysiology of asthma.

Proc Natl Acad Sci U S A, 2002 May 14, 99(10), 6838 - 42
The development of immunity in a social insect: evidence for the group facilitation of disease resistance; Traniello JF et al.; The extraordinary diversity and ecological success of the social insects has been attributed to their ability to cope with the rich and often infectious microbial community inhabiting their nests and feeding sites . Mechanisms of disease control used by eusocial species include antibiotic glandular secretions, mutual grooming, removal of diseased individuals from the nest, and the innate and adaptive immune responses of colony members . Here we demonstrate that after a challenge exposure to the entomopathogenic fungus Metarhizium anisopliae, dampwood termites Zootermopsis angusticollis have higher survivorship when individuals develop immunity as group members . Furthermore, termites significantly improve their ability to resist infection when they are placed in contact with previously immunized nestmates . This "social transfer" of infection resistance, a previously unrecognized mechanism of disease control in the social insects, could explain how group living may improve the survivorship of colony members despite the increased risks of pathogen transmission that can accompany sociality.

J Hered, 2002 Jan-Feb, 93(1), 27 - 36
Characterization of genetic markers for in vitro cell line identification of the marine sponge Axinella corrugata; Lopez JV et al.; The marine sponge Axinella corrugata is being developed as a model organism for in vitro marine invertebrate research . Molecular genetics methods such as DNA fingerprinting {amplified fragment length polymorphism (AFLP) and single-stranded conformation polymorphism (SSCP)} and single-locus DNA sequence analyses were applied to this model to meet the primary objective of identifying positive A . corrugata-specific molecular markers that will aid in verifying cell identity in vitro and distinguish sponge cells from potential microbial contaminants . The extent of intra- and interspecific variation in these markers from geographically distinct samples of A . corrugata and closely related sponge taxa was also assessed . Two novel nuclear loci along with intervening transcribed spacer (ITS) regions of nuclear rRNA were characterized, although the latter appeared to better meet primary marker criteria, such as taxonomic specificity and high frequency of detection (via polymerase chain reaction {PCR}) from different individuals (n > 40) and cell cultures . Phylogenetic and phylogeographic analyses of ITS DNA sequences helped clarify taxonomies and also suggested species boundaries between and among western Atlantic and eastern Atlantic/Indian Ocean A . corrugata and Axinellidae samples . Patterns of genetic variation have important implications for the systematics, evolution, and chemical ecology of A . corrugata and related axinellids and are discussed.

Braz J Infect Dis, 2001 Dec, 5(6), 339 - 44
High prevalence of giardiasis and stronglyloidiasis among HIV-infected patients in Bahia, Brazil; Feitosa G et al.; Diarrhea due to intestinal microbial infections is a frequent manifestation among HIV-infected patients . It has been postulated that HIV-infected patients may have special types of intestinal infections, and that immune activation from such parasites may affect the progression of HIV disease . To evaluate these associations, the frequency of infections was examined in HIV-infected patients in Bahia, Brazil . To determine the potential impact of the presence of intestinal parasitic infections on HIV disease progression, a retrospective study approach was used . The medical charts of 365 HIV-infected patients who had been treated at the AIDS Clinic of the Federal University of Bahia Hospital were reviewed, and the prevalence of parasites was compared with 5,243 HIV-negative patients who had attended the hospital during the same period of time . Among HIV-infected subjects, CD(4) count, RNA plasma viral load (VL), and number of eosinophils were compared according to their stool examination results . The overall prevalence of each parasite was similar for HIV-positive and HIV-negative patients . However, the prevalence of S . stercoralis (p<10(-7)) and G . lamblia (p=0.005) was greater for HIV-infected subjects . The mean CD(4) count and viral load of HIV patients in our clinic who had stool examinations was 350 cells +/- 340 and 4.4 +/- 1.4 log RNA viral load, respectively . In this patient group there was no clear association between the level of the absolute CD(4) count or the viral load and a specific parasitic infection . The presence of an intestinal parasitic infection was not associated with faster progression of the HIV disease among HIV-infected patients . We conclude that strongyloidiasis and giardiasis are more frequent in HIV-infected patients in Bahia, Brazil . If this association is due to immune dysregulation, as has been proposed elsewhere, it must occur in patients after only minor shifts in CD(4) count from normal levels, or as a result of immune dysfunction not represented by CD(4) count . These infections do not appear to alter the progression of HIV disease.

Mol Immunol, 2002 May, 38(12-13), 891 - 3
Positive and negative regulation of pathogen induced dendritic cell function by G-protein coupled receptors; Aliberti J et al.; The induction of IL-12 from dendritic cells (DC) is a major initiating step in host resistance to intracellular pathogens . We have studied the regulation of this response using an in vivo model in which IL-12 production by splenic CD8alpha+ DC is followed after injection of a soluble extract (STAg) of the protozoan parasite Toxoplasma gondii . Our findings indicate that the potent IL-12 response observed is highly dependent on both the chemokine receptor CCR5 and G(i)-protein coupled signaling . In addition, we have examined the basis of the unresponsiveness of DC to secondary STAg injection which occurs following primary exposure to this parasite stimulus . Our results demonstrate that this refractory state correlates with the down-regulation of CCR5 expression on DC which, in turn, appears to depend on the induction of endogenous lipoxin A(4) (LXA(4)), a product of arachidonic acid metabolism . Since LXA(4) is known to also signal through a G-protein coupled receptor pathway, these findings taken together support a major role for G-protein signaling in the regulation of microbial-induced DC function.

J Environ Sci Health B, 2002 May, 37(3), 255 - 64
Comparison of media and a liquid detergent extraction step on bacterial recovery from animal feeds; Maciorowski KG et al.; The objective of this study was to evaluate the recovery of Tryptic soy agar (TSA) or low nutrient R2 bacterial populations from fresh feeds and animal feeds held in long-term cold storage after extraction with a detergent-based solution combined with repeated centrifugation . Repeated centrifugation after exposure to a detergent-based solution resulted in recoveries generally no more than 10% of the microbial population in the original feed . Feed R2A populations were significantly correlated (P<0.01) with TSA populations enumerated from the feed and feed extracts, as well as R2A populations from feed extracts . Similarly, TSA bacterial populations from feed were significantly correlated with TSA populations from extracts.

Environ Pollut, 2002, 118(3), 445 - 52
In situ fixation of metals in soils using bauxite residue: biological effects; Lombi E et al.; Soils polluted with heavy metals can cause phytotoxicity and exhibit impared microbial activities . In this paper we evaluate the responses of different biological endpoints to in situ remediation processes . Three soil amendments (red mud, beringite and lime) were applied to two soils polluted by heavy metals . Oilseed rape, wheat, pea and lettuce were grown successively in pots on the untreated and amended soils and their yield and metal uptake were determined . A suite of microbial tests (lux-marked biosensors, Biolog and soil microbial biomass) were performed to determine the effect of the soil amendments on the functionality and size of the soil microbial community . In both soils all three amendments reduced phytotoxicity of heavy metals, enhanced plant yields and decreased the metal concentrations in plants . The red mud treatment also increased soil microbial biomass significantly . The microbial biosensors responded positively to the remediation treatments in the industrially-contaminated soil used in the experiment . Red mud applied at 2% of soil weight was as effective as beringite applied at 5% . The results also showed that since the biological systems tested respond differently to the alleviation of metal toxicity, a suite of biological assays should be used to assess soil remediation processes.

J Virol Methods, 2002 May 16, 103(2), 157 - 70
A multivariate statistical analysis to follow the course of disease after infection of cats with different strains of the feline immunodeficiency virus (FIV); de Monte M et al.; A descriptive multivariate assay is described which is suitable to analyze results of a biological experiment with small sample size but high qualitative and quantitative complexity of variables . This type of assay allows evaluation of multiple variables observed in the course of an experimental virus infection (e.g . viremia, nucleic acid detection, antibody titers, clinical parameters, anti-microbial treatments or vaccination) in a single graph . In our study, a multiple correspondence analysis (MCA) was used to correlate a total of 145 measurements from each of a dozen of variables measured in five groups of three cats infected by five isolates of feline immunodeficiency virus (FIV) . Three groups of virus isolates with distinct virulence were defined and correlation between dynamics of lymphocyte subset counts and viral virulence was established . Comparison between the primary stages of illness and follow-up examinations were of prognostic value and are thus helpful for development and monitoring of therapeutic strategies.

Science, 2002 May 10, 296(5570), 1061 - 3
Global dispersal of free-living microbial eukaryote species; Finlay BJ; The abundance of individuals in microbial species is so large that dispersal is rarely (if ever) restricted by geographical barriers . This "ubiquitous" dispersal requires an alternative view of the scale and dynamics of biodiversity at the microbial level, wherein global species number is relatively low and local species richness is always sufficient to drive ecosystem functions.

Waste Manag, 2002, 22(2), 187 - 93
Microbial influenced degradation of solidified waste binder; Knight J et al.; Ordinary cement pastes with water/cement (w/c) ratios of 0.2, 0.4 and 0.5 were used to examine the chemical and physical effects of microbial influenced degradation (MID) . Samples were exposed to an active culture of Thiobacillus thiooxidans or to sterile media containing sulphuric acid using an intermittent immersion technique . Acid consumption and Ca, Al and Fe releases are presented for an exposure period of 90 days . Exposed samples were also sectioned and analysed by scanning electron microscopy (SEM) and energy dispersive X-ray (EDX) . All cement paste samples were subject to significant degradation in either sterile acid media or the T . thiooxidans lixiviant . Corrosion depths observed from SEM examination of exposed samples were affected by the w/c ratio of the cement . The extent and rate of degradation were not apparent from the calculated rate of hydrogen ion consumption, or the leaching rates of Ca, Al and Fe . It was not possible to distinguish differences in corrosion due to the chemical and microbial influenced degradation from the results obtained to date and further work is focusing on modified procedures to address this.

Clin Exp Allergy, 2002 Jan, 32(1), 37 - 42
Coincidence of immune-mediated diseases driven by Th1 and Th2 subsets suggests a common aetiology . A population-based study using computerized general practice data; Simpson CR et al.; BACKGROUND: The recent rise in the prevalence of immune-mediated diseases has been attributed to environmental factors such as a lack of microbial challenge, or dietary change, that deviate the overall balance between mutually antagonistic subsets of T helper (Th) cells . OBJECTIVE: An alternative proposal is that recent environmental changes have resulted in an immune system that is more likely to produce both Th1 and Th2 responses against benign antigens . The prediction of this hypothesis, that Th1 and Th2-mediated diseases are not mutually exclusive, and may be positively associated, is tested here in a whole population . METHODS: Data from General Practices participating in the Scottish Continuous Morbidity Recording (CMR) project were used to determine the coincidence of the major Th2-mediated atopic diseases; asthma, eczema and allergic rhinitis, with the Th1-mediated autoimmune conditions; type I diabetes, rheumatoid arthritis and psoriasis . We also identified the prescription rates of inhaled therapy for asthma in patients with Th1-mediated disease . RESULTS: There was a significant increase in the risk of presenting with a Th1-mediated autoimmune condition in patients with a history of allergic disease (standardized prevalence ratio (95% confidence interval) 1.28 (1.18-1.37)) . Likewise, the standardized prevalence ratios of presenting with either eczema (1.67 (1.48-1.87)) or allergic rhinitis (1.22 (1.02-1.44)) were significantly increased in subjects with a history of Th1-mediated disease . There was a particularly strong association between current psoriasis and current eczema (standardized prevalence ratio ofpsoriasis in subjects with eczema 2.88, 95% confidence interval (CI) 2.38-3.45) . There was also a significant increase in prescriptions for inhaled asthma therapy in patients with Th1 disease . CONCLUSION: It is concluded that Th1- and Th2-mediated diseases are significantly associated in a large General Practice population . This finding supports the proposal that autoimmune and atopic diseases share risk factors that increase the propensity of the immune system to generate both Th1- and Th2-mediated inappropriate responses to non-pathological antigens.

Tohoku J Exp Med, 2002 Mar, 196(3), 179 - 84
CXC chemokine receptor 1 (CXCR1) is expressed mainly by neutrophils in inflamed gut and stomach tissues; Ohtani N et al.; CXC chemokine receptor 1 (CXCR1) is one of the important receptors for CXC chemokines with ELR motif, of which interleukin 8 (IL-8; CXCL8) is representative . To identify the cell type(s) of CXCR1-expressing cells in inflamed stomach and gut tissues, we performed immunoperoxidase method using pre-fixed frozen sections . In chronic gastritis associated with Helicobacter pylori infection (7 cases), CXCR1 was positive in neutrophils (polymorphonuclear leucocytes) in the lamina propria near the neck region and those in pit abscess . In ulcerative colitis (6 cases) and Crohn's disease (5 cases), CXCR1 was sporadically expressed by neutrophils in the mucosa, and particularly CXCR1+ neutrophils were abundantly distributed in inflammatory granulation tissue in ulcer base . Double staining confirmed co-localization of CXCR1 and neutrophil elastase . Neither CD3+ T lymphocytes nor CD68+ macrophages were positive for CXCR1 . Immunoelectron microscopy confirmed the cell surface localization of CXCR1 . Neutrophils protect the host from microbial pathogens . However, they also cause damages to host tissues in chronic inflammation . Therefore, our study underscores the importance of CXCR1 expression in inflammatory processes.

Mycopathologia, 2002, 153(2), 71 - 5
The importance of microscopic examination in the management of desquamative diseases of the scalp; Conti Diaz IA et al.; After determining the usual malassezic biota of the scalp in adult, normal persons, 259 patients with different desquamative diseases were studied by a simple adhesive tape technique . The main purpose of this study was to investigate the utility of this technique to improve the diagnosis and treatment of patients . Most patients with seborrhoeic dermatitis and sebopsoriasis demonstrated large numbers of Malassezia spp . cells corresponding to the so called "pityrosporosis" . Only 43.6% of patients with pityriasis capitis (dandruff) presented with such a diagnosis . Symptomatic pityrosporosis of the scalp should be treated with imidazolic derivatives or other antifungal substances . Patients with psoriasis of the scalp showed a typical microscopic picture represented by parakeratosic (nucleated) keratinocytes with absence of lipophilic yeasts which should be attributed to the usual dryness of the scales Microbial epidermitis (eczema) of the scalp revealed another characteristic picture constituted by abundant leukocytes and bacteria without the presence of yeasts . The different microscopic pictures seen with this simple technique for diseases of the scalp, offer an adjunct to make a proper diagnosis and to establish a convenient treatment in cases which are not clinically well defined.

Int J Food Microbiol, 2002 May 5, 75(1-2), 39 - 51
Quantitative risk assessment of human infection from Escherichia coli O157 associated with recreational use of animal pasture; Strachan NJ et al.; A quantitative microbial risk assessment incorporating Monte Carlo simulations is described which estimates the probability of Escherichia coli O157 infection of humans by visiting pasture previously grazed by cattle . The risk assessment is performed for a number of scenarios including a variation in the grazing period prior to the human visit, the duration of visit (8-h day or 24-h camp) and the level of E . coli O157 shed by the cattle . Assuming the cattle have been on the field for 28 days, followed directly by a human visit, and the proportion of animals shedding the organism are as described in previous surveys 5 +/- 1% (Synge, B.A., Gunn, G.J., Ternent, H.E., Hopkins, G.F., Thomson-Carter, F., Foster, G., Chase-Topping, M., McKendrick, I., 2001) . Prevalence and factors affecting the shedding of verocytotoxin producing Escherichia coli O157 in beef cattle in Scotland . In: Concerted Action CT98-3935 Veroctotoxigenic E . coli in Europe, 5 . Epidemiology of Verocytotoxigenic E . coli, Dublin, pp . 98-103.), a probability of infection of 0.1% is attained for 8- and 24-h periods when the cattle are shedding approximately 10(3) and 10(4) CFU g(-1), respectively . Monte Carlo simulations demonstrated that risk mitigation strategies of removing cattle from the pasture 4 weeks prior to the human visit in addition to physical removal of faeces showed significant reductions in potential infection rates.

Int J Food Microbiol, 2002 May 5, 75(1-2), 127 - 33
Variation among Escherichia coli O157:H7 strains relative to their growth, survival, thermal inactivation, and toxin production in broth; Whiting RC et al.; To estimate the potential outcomes of food processing on the fate of foodborne pathogens . variations in microbial parameters such as growth rate, survival time, thermal inactivation time, and toxin production must be known . Previous microbial studies using single strains or cocktails provide error estimates for the uncertainty of the experimental and statistical procedures, but not for variations among strains . In this study, the behavior of 17 strains of Escherichia coli O157:H7 were followed when placed in synthetic media that permitted growth, survival, or thermal inactivation . The parameter values were not rejected as being normal, lognormal, gamma, or Weibull distributions . The ratio of the standard deviation to mean (normal distribution) for the exponential growth rate was 0.16 and for the lag phase duration, it was 0.38 . The ratios of times to achieve a 4-log10 reduction at two survival conditions were 0.39 and 0.46; ratios of thermal D values at 55 and 60 degrees C were 0.42 and 0.33, respectively . The ratio of the negative log10 of toxin production was 0.24 . These distributions are larger than the coefficient of variations observed for experimental errors in single strain and cocktail experiments . This indicates the limitations in precision that predictions of future population numbers can have when the potential presence of all strains needs to be considered . This variation among strains is applicable whether predictions are made by traditional subjective and point estimates or by using models and risk assessments.

Environ Sci Technol, 2002 Apr 1, 36(7), 1452 - 9
Modeling the inhibition of the bacteral reduction of U(VI) by beta-MnO2(s); Liu C et al.; Pyrolusite (beta-MnO2(s)) was used to assess the influence of a competitive electron acceptor on the kinetics of reduction of aqueous uranyl carbonate by a dissimilatory metal-reducing bacterium (DMRB), Shewanella putrefaciens strain CN32 . The enzymatic reduction of U(VI) and beta-MnO2(s) and the abiotic redox reaction between beta-MnO2(s) and biogenic uraninite (UO2(s)) were independently investigated to allow for interpretation of studies of U(VI) bioreduction in the presence of beta-MnO2(s) . Uranyl bioreduction to UO2(s) by CN32 with H2 as the electron donor followed Monod kinetics, with a maximum specific reduction rate of 110 M/h/10(8) cells/mL and a half-saturation constant of 370 microM . The bioreduction rate of beta-MnO2(s) by CN32 was described by a pseudo-first-order model with respect to beta-MnO2(s) surface sites, with a rate constant of 7.92 x 10(-2) h(-1)/10(8) cells/mL . Uraninite that precipitated as a result of microbial U(VI) reduction was abiotically reoxidized to U(VI) by beta-MnO2(s), with concomitant reduction to Mn(II) . The oxidation of biogenic UO2(s) coupled with beta-MnO2(s) reduction was well-described by an electrochemical model . However, a simple model that coupled the bacterial reduction of U(VI) and beta-MnO2(s) with an abiotic redox reaction between UO2(s) and beta-MnO2(s) failed to describe the mass loss of U(VI) in the presence of beta-MnO2(s) . Transmission electron microscopy (TEM) and energy dispersive spectroscopy (EDS) revealed that the particle size and spatial distribution of the biogenic UO2(s) changed dynamically in systems with, as compared to without, beta-MnO2(s)) . These observations suggested that the surface properties and localization of UO2(s) in relation to the cell and beta-MnO2(s) surfaces was an important factor controlling the abiotic oxidation of UO2(s) and, thus, the overall rate and extent of U(VI) bioreduction . The coupled model that was modified to account for the "effective" contact surface area between UO2(s) and beta-MnO2(s) significantly improved the simulation of microbial reduction of U(VI) in the presence of beta-MnO2(s).

Rev Stomatol Chir Maxillofac, 2002 Apr, 103(2), 96 - 104
{Diffuse sclerosing osteomyelitis of the mandible and SAPHO syndrome}; Fleuridas G et al.; BACKGROUND: Diffuse sclerosing osteomyelitis of the mandible (DSOM) and SAPHO (synovitis, acne, palmo-plantar pustulosis and psoriasis, hyperosteosis, osteitis) syndrome are not commonly associated . SAPHO has not been described to date in the stomatology and maxillo-facial surgery literature in French . Were report here a homogeneous series of 12 patients with DSOM . MATERIAL AND METHODS: All patients had mandibular osteitis.RESULTS: Five patients with multifocal osteitis wre considered to present SAPHO syndrome because of the associated skin lesions . One patient with a unique focus of mandibular osteitis and palmo-plantar pustulosis probably had early-stage SAPHO syndrome . The diagnosis in the other cases was diffuse sclerosis osteitis of the mandible . DISCUSSION: We compared our series with those reported in the literature, emphasizing diagnostic and therapeutic difficulties . Diffuse sclerosing osteomyelitis of the mandible should be distinguished from microbial osteitis . Early diagnosis is required to avoid successive and unnecessary dental avulsions . There is a possible link between DSOM and SAPHO and all patients should have a complete work-up including whole-body scintigraphy to search for other foci . A biopsy is indicated to rule out malignancy . Nonsteroidal antiinflammatory drugs can improve patient comfort in this particularly long syndrome . Although the efficacy is demonstrated, surgery and antibiotics can only delay relapse for a few months.

Br Med Bull, 2002, 61, 97 - 114
Recent advances in the rapid diagnosis of respiratory tract infection; Myint S; Molecular techniques have enabled major advances in the speed and sensitivity of the laboratory diagnosis of respiratory infections . Although the polymerase chain reaction is the most commonly used, there are several other methods available, which have applicability across the range of microbial pathogens.

Br Med Bull, 2002, 61, 1 - 12
Pulmonary defences to acute respiratory infection; Boyton RJ et al.; Of all sites in the body, the lung is perhaps challenged by the greatest onslaught of microbial pathogens, many of which would cause lethal infections if unopposed . The immune response to respiratory infection must, therefore, be rapid and efficient . However, the respiratory tract is a fragile tissue with architecture that is finely designed for gas exchange, so that the price of excessive or inappropriate inflammatory responses may itself be very high . The first line of defence comes from barriers such as mucus and cilia, followed by a battery of mediators that constitute the innate response . These include lactoferrin, lysozyme, collectins and defensins . Activation of these molecules can lead directly to lysis of pathogens, or to destruction through opsonisation or the recruitment of inflammatory cells . The adaptive immune response includes the production of neutralising antibodies and the responses of T lymphocytes . Different populations of T lymphocytes may dramatically alter the balance between clearance of the pathogen and induction of tissue damage depending on the cytokines they secrete.

FEBS Lett, 2002 May 8, 518(1-3), 164 - 8
cDNA cloning and characterization of tobacco ABC transporter: NtPDR1 is a novel elicitor-responsive gene; Sasabe M et al.; We isolated an INF1 elicitin-inducible cDNA encoding a pleiotropic drug resistance (PDR)-type ATP-binding cassette (ABC) transporter homolog (NtPDR1) in suspension-cultured tobacco Bright Yellow-2 (BY-2) cells by application of differential display PCR . The NtPDR1 (Nicotiana tabacum PDR protein 1) gene also encodes a 162 kDa protein that includes two putative hydrophilic domains containing the ABC signature motif and two putative hydrophobic domains . Expression of the NtPDR1 gene was rapidly and strongly activated by treatment of BY-2 cells with INF1 elicitin . Further, treatment of BY-2 cells with flagellin, a bacterial proteinaceous hypersensitive reaction elicitor, or yeast extract, a general elicitor, also induced NtPDR1 gene expression . These results indicate that NtPDR1 may be involved in the general defense response in tobacco . This is the first report that microbial elicitors induce the expression of a plant ABC transporter gene.

J Am Chem Soc, 2002 May 15, 124(19), 5431 - 40
Solution-phase parallel synthesis of a pharmacophore library of HUN-7293 analogues: a general chemical mutagenesis approach to defining structure-function properties of naturally occurring cyclic (depsi)peptides; Chen Y et al.; HUN-7293 (1), a naturally occurring cyclic heptadepsipeptide, is a potent inhibitor of cell adhesion molecule expression (VCAM-1, ICAM-1, E-selectin), the overexpression of which is characteristic of chronic inflammatory diseases . Representative of a general approach to defining structure-function relationships of such cyclic (depsi)peptides, the parallel synthesis and evaluation of a complete library of key HUN-7293 analogues are detailed enlisting solution-phase techniques and simple acid-base liquid-liquid extractions for isolation and purification of intermediates and final products . Significant to the design of the studies and unique to solution-phase techniques, the library was assembled superimposing a divergent synthetic strategy onto a convergent total synthesis . An alanine scan and N-methyl deletion of each residue of the cyclic heptadepsipeptide identified key sites responsible for or contributing to the biological properties . The simultaneous preparation of a complete set of individual residue analogues further simplifying the structure allowed an assessment of each structural feature of 1, providing a detailed account of the structure-function relationships in a single study . Within this pharmacophore library prepared by systematic chemical mutagenesis of the natural product structure, simplified analogues possessing comparable potency and, in some instances, improved selectivity were identified . One potent member of this library proved to be an additional natural product in its own right, which we have come to refer to as HUN-7293B (8), being isolated from the microbial strain F/94-499709.

Biol Pharm Bull, 2002 Apr, 25(4), 446 - 51
Characterization of rat aortic fragment within collagen gel as an angiogenesis model; capillary morphology may reflect the action mechanisms of angiogenesis inhibitors; Hata-Sugi N et al.; A fragment of rat thoracic aorta within type I collagen gel was employed as a model of angiogenesis, including the processes of cell migration, proliferation and capillary tube formation . Endogenous angiogenic factors in this model were studied . Expressions of vascular endothelial growth factor (VEGF) and its receptor, and proteolytic enzyme activities (matrix metalloprotease-2; MMP-2 and plasminogen activator; PA) increased during angiogenesis . The angiogenesis was inhibited by VEGF receptor kinase inhibitor and MMP inhibitor, confirming that these endogenous factors played an important role in angiogenesis . Interestingly, these inhibitors induced different capillary morphologies, including differences of cell migration and sprouting . Furthermore, dexamethasone (a down-regulator of MMP and PA) and TNP-470 (an endothelial cell growth inhibitor) induced another capillary morphology . The results suggest that the capillary structure in this model is dramatically influenced by the inhibition of angiogenic signalling and extracellular matrix (ECM) degradation . We also found that a novel angiogenesis inhibitor, the microbial metabolite luminacin, which was recently identified by us (Wakabayashi et al., J . Antiobiot., 53, 591-596 (2000)), induced a different morphology compared with other inhibitors examined, suggesting that it has a unique mechanism of action . Our results indicate that this rat aorta model should be useful for screening novel angiogenesis inhibitors.

J Allergy Clin Immunol, 2002 May, 109(5), 858 - 66
Reduced soluble CD14 levels in amniotic fluid and breast milk are associated with the subsequent development of atopy, eczema, or both; Jones CA et al.; BACKGROUND: Exposure to various microbial products in early life reduces the risk of atopy . Such exposure induces downregulation of T(H)2 allergy-biased responses by means of pattern recognition molecules, such as CD14, an LPS receptor . OBJECTIVE: We sought to determine whether infant and maternal levels of soluble CD14 (sCD14) are associated with the atopic outcomes of infants . METHODS: Levels of sCD14 in plasma, amniotic fluid, and breast milk were measured with a specific ELISA in different cohorts . Expression of toll-like receptors in the fetal gut was examined by using RT-PCR . RESULTS: Soluble CD14 levels increased during fetal development and postnatally, attaining adult levels by around 4 months of age, with an overshoot of adult levels from 6 months of age . There was no difference in plasma sCD14 levels at birth of children with a high compared with those with a low risk of development of atopy . Amniotic fluid sCD14 levels at midgestation (16-17 weeks) were significantly lower when the child was subsequently atopic (P <.05) . Soluble CD14 levels in breast milk collected 3 months postpartum were significantly lower in children with eczema at 6 months of age, irrespective of whether they were atopic (P =.003) . Transcripts for toll-like receptor 4, which would enable transmembrane signaling for LPS/sCD14 complexes, were expressed within fetal gut and skin . CONCLUSION: Exposure to reduced levels of sCD14 in the fetal and neonatal gastrointestinal tract is associated with the development of atopy, eczema, or both . Thus the exogenous supply of sCD14 might influence immunologic reactivity both locally and systemically in early life and thereby influence disease outcome.

J Immunol, 2002 May 15, 168(10), 4854 - 63
Immunostimulatory CpG-DNA activates murine microglia; Dalpke AH et al.; Bacterial DNA containing motifs of unmethylated CpG dinucleotides (CpG-DNA) triggers innate immune cells through the pattern recognition receptor Toll-like receptor 9 (TLR-9) . CpG-DNA possesses potent immunostimulatory effects on macrophages, dendritic cells, and B lymphocytes . Therefore, CpG-DNA contributes to inflammation during the course of bacterial infections . In contrast to other TLR-dependent microbial patterns, CpG-DNA is a strong inductor of IL-12 . Thus, it acts as a Th1-polarizing agent that can be utilized as potent vaccine adjuvant . To assess the role of CpG-DNA in immune reactions in the CNS, we analyzed the effects of CpG-DNA on microglial cells in vitro and in vivo . Primary microglial cells as well as microglial cell lines express TLR-9 mRNA . Consequently, CpG-DNA activated microglial cells in vitro and induced TNF-alpha, IL-12p40, IL-12p70, and NO . Furthermore, MHC class II, B7-1, B7-2, and CD40 molecules were up-regulated . In addition, phagocytic activity of microglia was enhanced . After intracerebroventricular injection of CpG-DNA, microglial cells were activated and produced TNF-alpha and IL-12p40 transcripts, as shown by in situ hybridization . These results indicate that microglia is sensitive to CpG-DNA . Thus, bacterial DNA containing CpG motifs could not only play an important role during infections of the CNS, but also might trigger and sustain Th1-dominated immunopathogenic reactions.

J Biol Chem, 2002 Jul 19, 277(29), 26501 - 7 Epub 2002 May 06.
A novel, high performance enzyme for starch liquefaction . Discovery and optimization of a low pH, thermostable alpha-amylase; Richardson TH et al.; High throughput screening of microbial DNA libraries was used to identify alpha-amylases with phenotypic characteristics compatible with large scale corn wet milling process conditions . Single and multiorganism DNA libraries originating from various environments were targeted for activity and sequence-based screening approaches . After initial screening, 15 clones were designated as primary hits based upon activity at pH 4.5 or 95 degrees C without addition of endogenous Ca(2+) . After further characterization, three enzyme candidates were chosen each with an exceptional expression of one or more aspects of the necessary phenotype: temperature stability, pH optimum, lowered reliance on Ca(2+) and/or enzyme rate . To combine the best aspects of the three phenotypes to optimize process compatibility, the natural gene homologues were used as a parental sequence set for gene reassembly . Approximately 21,000 chimeric daughter sequences were generated and subsets screened using a process-specific, high throughput activity assay . Gene reassembly resulted in numerous improved mutants with combined optimal phenotypes of expression, temperature stability, and pH optimum . After biochemical and process-specific characterization of these gene products, one alpha-amylase with exceptional process compatibility and economics was identified . This paper describes the synergistic approach of combining environmental discovery and laboratory evolution for identification and optimization of industrially important biocatalysts.

J Environ Monit, 2002 Apr, 4(2), 300 - 5
Heavy metal speciation in the composting process; Greenway GM et al.; Composting is one of the more efficient and environment friendly methods of solid waste disposal and has many advantages when compared with landfill disposal on which the UK and Ireland are currently heavily dependent . Composting is a very complicated process involving intensive microbial activity and the detailed mechanisms of the process have yet to be fully understood . Metal speciation information can provide an insight into the metal-microbial interaction and would help in the evaluation of the quality of compost . This would facilitate the exploitation of composts in remediation of heavy metal contaminated land . In this work a systematic approach to metal speciation in compost has been taken by applying the three-step method for operationally defined metal speciation of soils and sediments, developed by the European Commission's Standards, Measurement and Testing Programme to monitor the change in metal speciation with time (up to 106 days) for four different waste composting processes . The results have shown that in general metals become less available for the first extraction step as the composting process proceeds . This implies that composting tends to redistribute the metals from more labile forms to more fixed forms which may explain why the application of composts could be useful for with heavy metal contaminated land . There are exceptions to this trend and in some cases, certain metals appear to behave differently depending on the source of the compost.

Adv Biochem Eng Biotechnol, 2002, 74, 239 - 59
Bulk chemicals from biotechnology: the case of 1,3-propanediol production and the new trends; Zeng AP et al.; The need for a sustainable resource supply, the rapid advances in plant biotechnology and microbial genetics and the strategic shift of major chemical companies into the area of life sciences are some of the driving forces for renewed interest in producing bulk chemicals from renewable resources by biological processes . The microbial production of 1,3-propanediol as briefly reviewed in this article and compared with the competing chemical processes demonstrates the promise and constraints of bioprocesses for bulk chemicals . The new concept of biorefinery and biocommodity engineering and future research needs in this area are also outlined.

Bioresour Technol, 2002 May, 82(3), 209 - 13
Selective production of organic acids in anaerobic acid reactor by pH control; Horiuchi JI et al.; The selective production of organic acids by anaerobic acidogenesis with pH control was examined using a chemostat culture . The results showed that the product spectrum in the acid reactor strongly depended on the culture pH . Under acidic and neutral conditions, the main products were butyric acid, while acetic and propionic acids were the main products under the basic condition . This phenomenon was reversible between the acidic and basic conditions, and was not affected by the dilution rate . The change in the main products was caused by the change in the dominant microbial populations, from butyric acid-producing bacteria to propionic acid-producing bacteria in the acid reactor due to the pH shift . The control of culture pH was considered to be a useful way for controlling the product spectrum in the anaerobic acid reactor.

Blood, 2002 May 15, 99(10), 3844 - 7
Herpes simplex virus type 2-specific CD8 cytotoxic T lymphocyte cross-reactivity against prevalent HLA class I alleles; Koelle DM et al.; Clonally expressed T-cell receptor alphabeta heterodimers are able to bind many different major histocompatibility complex/peptide combinations . This promiscuity is thought to be required for adequate surveillance against microbial and malignancy-associated antigens . After transplantation, T cells may react with nonself structures, contributing to graft-versus-host disease, in the case of hematopoietic stem cell transplantation, or graft failure, when the host immune system is preserved . We describe 2 distinct HLA A*0201-restricted, cytotoxic CD8 T-cell responses to the prevalent chronic pathogen, herpes simplex virus type 2, that cross-react with cells bearing specific alleles of the common HLA B44 family . Transfection of human or primate renal epithelial cells with HLA class I complementary DNA confirmed these results . Given the prevalence of this viral infection and the HLA alleles involved, it is possible that this cross-reactivity may be involved in clinically significant events.

Ophthalmology, 2002 May, 109(5), 862 - 8
Limbal stem cell transplantation in chronic inflammatory eye disease; Samson CM et al.; OBJECTIVE: The goal of this study was to describe the outcome of limbal stem cell transplantation (LSCT) in patients with severe ocular surface disease caused by underlying chronic inflammatory eye disease . DESIGN: Retrospective noncomparative case series . PARTICIPANTS: Nine patients with limbal stem cell deficiency caused by an underlying ocular inflammatory disease who underwent LSCT . METHODS: The authors reviewed the records of 11 eyes of 9 patients with immunologically mediated ocular surface disease that underwent LSCT . MAIN OUTCOME MEASURES: The main outcome measures were reepithelialization of the corneal surface, restoration of corneal surface, and improvement in visual acuity . RESULTS: A total of 11 eyes underwent either autologous (n = 1) or HLA-matched living related donor (n = 10) LSCT for ocular surface disease secondary to inflammatory disease . Reepithelialization of the corneal surface in the immediate postoperative period occurred in 10 eyes (91%) within an average of 10 days (range, 3-21 days) . Long-term restoration of the corneal surface was achieved in six (55%) eyes . Visual acuity improved in six eyes (55%) . Reasons for poor outcomes included microbial infection, limbal stem cell graft rejection, and corneal ulceration . No donor eyes had complications . CONCLUSIONS: Patients with underlying immunologically mediated diseases, such as Stevens-Johnson syndrome, toxic epidermal necrolysis, or ocular cicatricial pemphigoid, who undergo LSCT have lower success rates than do those patients with noninflammatory ocular surface diseases.

Phytochemistry, 2002 May, 60(1), 27 - 32
Ultraviolet induced stress response in fresh cut cantaloupe; Lamikanra O et al.; Changes in the composition of volatile compounds in cantaloupe melon (Cucumis melo L . var . reticulatus) as a result of UV induced stress were determined by gas chromatography-mass spectrometry (GC-MS) . Several volatile ester compounds were present, of which twenty-seven were identified in fresh cut cantaloupe . Fruit exposure to UV light decreased the concentrations of most of the aliphatic esters by over 60% of the amounts present in the corresponding fresh cut fruit . Cyclic and acyclic terpenoids, including phytoalexin compounds beta-ionone, geranylacetone and terpinyl acetate, were also produced as a result of UV exposure for 15 and 60 min, respectively . beta-Ionone, when added to crushed cantaloupe (0.01% w/w) completely inhibited microbial growth in the fruit for 24 h at 20 degrees C . Geranylacetone and terpinyl acetate reduced the microbial population from 6.3x10(8) in the untreated control to 1.2x10(8) and 3.5x10(7) CFU/g respectively . The results indicate the potential use of UV induced stress for screening cantaloupe melon cultivars for disease resistance, and as a minimal processing method to extend the shelf life of fresh cut cantaloupe products.

Clin Exp Immunol, 2002 May, 128(2), 326 - 32
Effect of CD14 promoter polymorphism and H . pylori infection and its clinical outcomes on circulating CD14; Karhukorpi J et al.; CD14 is a pattern recognition receptor on the membranes of monocytes and macrophages for several microbial products, of which lipopolysaccharide (LPS) is the best known . A shed form of CD14 is present in serum . As the CD14 gene promoter polymorphism -159C/T and some bacterial infections may affect the sCD14 levels, we compared the impact of both the CD14 promoter polymorphism and Helicobacter pylori infection on serum sCD14 levels in 201 dyspeptic patients (group 1) who had undergone gastroscopy, and 127 staff members (group 2) with no endoscopy . sCD14 was measured from the sera by a commercial enzyme immunoassay (EIA), and CD14 genotyping was carried out with PCR . Helicobacter pylori infection was detected by serology and/or culture or PCR . sCD14 levels were elevated in the subjects carrying the T allele (CT or TT genotype) in both groups when compared with subjects with the CC genotype . Overall, H . pylori-positive subjects tended to have higher sCD14 levels compared with H . pylori-negative subjects . In group 1 consisting of dyspeptic patients, those with gastric ulcer, gastric erosion or duodenal ulcer had significantly elevated levels of sCD14 compared with the patients with normal endoscopic findings or macroscopic gastritis . The recent use of NSAIDs was also associated with enhanced sCD14 . Thus, we were able to show several factors, one genetic and the other environmental (H . pylori infection and mucosal lesion), to have an impact on sCD14.

Clin Exp Immunol, 2002 May, 128(2), 318 - 25
Defining a T-cell epitope within HSP 65 in recurrent aphthous stomatitis; Hasan A et al.; The 65 kD heat shock protein (HSP) has been implicated in the aetiology of recurrent aphthous stomatitis (RAS) . We have previously demonstrated that peptide 91-105 derived from the sequence of mycobacterial 65 kD HSP stimulates specifically lymphocytes from patients with RAS . In this investigation, we show that both CD4+ and CD8+ T cells were significantly stimulated with mycobacterial peptide 91-105 . In contrast, the human homologous peptide 116-130 stimulated only CD4+ T cells . Inhibition studies showed that CD4+ T cells were class II restricted, whereas CD8+ T cells were class I restricted . We then used truncated or substituted peptides, and demonstrated that residues 95-105 appear to be important, and residue 104(Arg) critical, in stimulating the T cells . Thus, peptide 95- 105 may constitute a T-cell proliferative epitope in RAS . We postulate that the high load of micro-organisms that colonize the oral mucosa may initiate an immune response by the microbial HSP 65-derived peptide 95-105, stimulating the numerous Langerhans cells in the oral mucosa to activate a cross-reacting immune response to the homologous peptide 116-130 within the epithelial HSP 60, initiating the immunopathological changes that lead to RAS.

Microb Ecol, 2002 Jan, 43(1), 67 - 81 Epub 2002 Jan 23.
Food web structure in the recently flooded Sep Reservoir as inferred from phytoplankton population dynamics and living microbial biomass; Tadonleke RD et al.; Phytoplankton dynamics, bacterial standing stocks and living microbial biomass (derived from ATP measurements, 0.7-200 mm size class) were examined in 1996 in the newly flooded (1995) Sep Reservoir ('Massif Central,' France), for evidence of the importance of the microbial food web relative to the traditional food chain . Phosphate concentrations were low, N:P ratios were high, and phosphate losses converted into carbon accounted for <50% of phytoplankton biomass and production, indicating that P was limiting phytoplankton development during the study . The observed low availability of P contrasts with the high release of "directly" assimilable P often reported in newly flooded reservoirs, suggesting that factors determining nutrient dynamics in such ecosystems are complex . The phosphate availability, but also the water column stability, seemed to be among the major factors determining phytoplankton dynamics, as (i) large-size phytoplankton species were prominent during the period of increasing water column stability, whereas small-size species dominated phytoplankton assemblages during the period of decreasing stability, and (ii) a Dinobryon divergens bloom occurred during a period when inorganic P was undetectable, coinciding with the lowest values of bacterial standing stocks . Indication of grazing limitation of bacterial populations by the mixotrophic chrysophyte D . divergens (in late spring) and by other potential grazers (mainly rotifers in summer) seemed to be confirmed by the Model II or functional slopes of the bacterial vs phytoplankton regressions, which were always <0.63 . Phytoplankton biomass was not correlated with phosphorus sources and its contribution was remarkably low relative to the living microbial biomass which, in contrast, was positively correlated with total phosphorus in summer . We conclude that planktonic microheterotrophs are strongly implicated in the phosphorus dynamics in the Sep Reservoir, and thus support the idea that an important amount of matter and energy flows through the "microbial loop" and food web, shortly after the flooding of a reservoir.

Microb Ecol, 2002 Jan, 43(1), 55 - 66
A cross-system comparison of bacterial and fungal biomass in detritus pools of headwater streams; Findlay S et al.; The absolute amount of microbial biomass and relative contribution of fungi and bacteria are expected to vary among types of organic matter (OM) within a stream and will vary among streams because of differences in organic matter quality and quantity . Common types of benthic detritus {leaves, small wood, and fine benthic organic matter (FBOM)} were sampled in 9 small (1st-3rd order) streams selected to represent a range of important controlling factors such as surrounding vegetation, detritus standing stocks, and water chemistry . Direct counts of bacteria and measurements of ergosterol (a fungal sterol) were used to describe variation in bacterial and fungal biomass . There were significant differences in bacterial abundance among types of organic matter with higher densities per unit mass of organic matter on fine particles relative to either leaves or wood surfaces . In contrast, ergosterol concentrations were significantly greater on leaves and wood, confirming the predominance of fungal biomass in these larger size classes . In general, bacterial abundance per unit organic matter was less variable than fungal biomass, suggesting bacteria will be a more predictable component of stream microbial communities . For 7 of the 9 streams, the standing stock of fine benthic organic matter was large enough that habitat-weighted reach-scale bacterial biomass was equal to or greater than fungal biomass . The quantities of leaves and small wood varied among streams such that the relative contribution of reach-scale fungal biomass ranged from 10% to as much as 90% of microbial biomass . Ergosterol concentrations were positively associated with substrate C:N ratio while bacterial abundance was negatively correlated with C:N . Both these relationships are confounded by particle size, i.e., leaves and wood had higher C:N than fine benthic organic matter . There was a weak positive relationship between bacterial abundance and streamwater soluble reactive phosphorus concentration, but no apparent pattern between either bacteria or fungi and streamwater dissolved inorganic nitrogen . The variation in microbial biomass per unit organic matter and the relative abundance of different types of organic matter contributed equally to driving differences in total microbial biomass at the reach scale.

Microb Ecol, 2002 Jan, 43(1), 34 - 43 Epub 2001 Nov 22.
Eco-physiological characterization of soil bacterial populations in different states of growth; Di Mattia E et al.; The method based on characterization of microbial populations in terms of their growth rate in agar plates has been used for testing the prediction of the theory of r- and K-selection in a microbial community from a tropical soil . Conditions which could lead bacterial populations to grow exponentially or to enter into a stationary phase were obtained by growing soil microbial populations in a chemostat and in a chemostat with recycle, respectively . Significant differences in population distribution patterns were observed by comparing results from the two growth systems . When soil community was grown in a chemostat and subjected specifically to well-defined r- and K-conditions, stable associations of organisms with r- and K-type characteristics developed as a consequence of environmental pressure . In contrast, when cultivated in chemostat with recycle under the same r- and K-conditions imposed on chemostat cultures, distribution patterns of r- and K-selected populations appeared very little affected by changes in substrate availability.

Vaccine, 2002 May 6, 20(15), 1938 - 41
Innate T cell immunity to HIV-infection . Immunotherapy with phosphocarbohydrates, a novel strategy of immune intervention?
Gougeon ML, Malkovsky M, Casetti R, Agrati C, Poccia F.
Natural T (NT) lymphocytes recognize infected cells or microbial compounds without the classical genetic restriction of polymorphic major histocompatibility complex (MHC) molecules . NT cells are mainly composed of alphabeta and gammadelta T lymphocytes that express natural killer (NK) receptors and recognize preferentially various nonpeptidic antigens . Similar to NK cells, NT lymphocytes can see and kill target cells deficient in the expression of one or more MHC class I molecules . NT cells expressing the alphabeta TCR can recognize lipid and lipoglycan antigens presented in the context of nonpolymorphic CD1 molecules, whereas phosphocarbohydrates and alkylamines induce constitutive response of Vgamma9Vdelta2 T cells . The stimulation of Vgamma9Vdelta2 T cells with phosphocarbohydrates induces the production of cytokines (IFNgamma and TNFalpha) and the release of chemokines with suppressive activity on HIV replication . In addition, stimulated Vgamma9Vdelta2 T cells exert a cytolytic activity against HIV-infected targets . In HIV-infected patients, a quantitative and qualitative alteration is observed early during the infection . Vgamma9Vdelta2 T cells are deleted and the remaining gammadelta cells are anergic . Th1 cytokines (IL-12 and IL-15) positively regulate cytokine production by Vgamma9Vdelta2 T cells but they are inefficient in restoring normal functions in patients' gammadelta T cells . Interestingly, partial restoration of the immune system under highly active antiretroviral therapies (HAART) is associated to the recovery of functional Vgamma9Vdelta2 T cells . A large panel of phosphocarbohydrates able to selectively stimulate Vgamma9Vdelta2 T cells is currently available, and preliminary experiments in monkeys suggest their in vivo efficacy in helping to control SIV replication . These observations prompt the question of new immune intervention involving molecules that stimulate NT cells.

Genome Biol . 2002;3(4):REVIEWS1010 . Epub 2002 Mar 27.
Screening the fruitfly immune system; Dionne MS et al.; The anti-microbial defense system of Drosophila shows functional similarities with the vertebrate innate immune system . Two recent gene-expression profiling studies of fruitflies challenged with infectious agents have identified key molecular players in the fruitfly's response to bacterial and fungal infection, as well as a large number of immune-regulated genes with unknown immunological function.

Curr Opin Rheumatol, 2002 May, 14(3), 270 - 5
Novel pathways that regulate tumor necrosis factor-alpha production in rheumatoid arthritis; Gracie JA et al.; Clinical intervention studies have clearly shown the benefit in suppressing tumor necrosis factor-alpha (TNF-alpha) rheumatoid arthritis (RA) . In consequence, considerable interest has arisen in those pathways that in turn regulate TNF-alpha production, because they may offer further possible therapeutic targets . Several candidate pathways are currently being investigated . They include T cell/macrophage interactions mediated primarily through cell-cell membrane contact; novel cytokine activities; microbial-derived products, in particular bacterial deoxyribonucleic acid sequences; autoreactive T cells, and immunoglobulins . At the subcellular level, there is further interest in targeting signaling and mRNA processing and cytokine cleavage pathways required for optimal TNF-alpha production . The key recent observations in these areas, particularly in the extracellular compartment, are reviewed.

C R Biol, 2002 Feb, 325(2), 171 - 7
Copepod feeding in a tuna fishery area of the tropical Atlantic Ocean; Champalbert G et al.; Biomass, feeding and metabolic rates of planktonic copepods were studied in an oligotrophic area of the tropical Atlantic Ocean during an instability wave period (boreal summer) and a stratified period (boreal winter) . In summer, zooplankton biomass was higher than in winter, showing a positive effect of the instability wave . Moreover, feeding equilibrated metabolic expenditures of copepods in most cases during the instability . In contrast, in stratified conditions copepods did not equilibrate their metabolic budget . Our results suggest that the microbial loop was the dominant trophic pathway during both periods but with a quicker cycling during the instability.

Indoor Air, 2000 Jun, 10(2), 111 - 20
The relationship between measured moisture conditions and fungal concentrations in water-damaged building materials; Pasanen AL et al.; We determined the moisture levels, relative humidity (RH) or moisture content (MC) of materials, and concentrations of culturable fungi, actinomycetes and total spores as well as a composition of fungal flora in 122 building material samples collected from 18 moisture problem buildings . The purpose of this work was to clarify if the is any correlation between the moisture parameters and microbial levels or generic composition depending on the type of materials and the time passed after a water damage . The results showed an agreement between the concentrations of total spores and culturable fungi for the wood, wood-based and gypsum board samples (r > 0.47) . The concentrations of total spores and/or culturable fungi correlated with RH of materials particularly among the wood and insulation materials (r > 0.79), but not usually with MC (r < 0.45) . For the samples collected from ongoing damage, there was a correlation between RH of materials and the concentrations of total spores and culturable fungi (r > 0.51), while such a relationship could not be observed for the samples taken from dry damage . A wide range of fungal species were found in the samples from ongoing damage, whereas Penicillia and in some cases yeasts dominated the fungal flora in the dry samples . This study indicates that fungal contamination can be evaluated on the basis of moisture measurements of constructions in ongoing damage, but the measurements are not solely adequate for estimation of possible microbial growth in dry damage.

Curr Opin Infect Dis, 2001 Apr, 14(2), 193 - 7
Bronchiectasis; Angrill J et al.; Bronchiectasis is a structural derangement of the bronchial wall that is characterized by airway dilatation and bronchial wall thickening . As a result of this abnormality, chronic inflammation and secondary microbial infections occur, which cause additional damage to the bronchi . Recent insights into the potential pathophysiological mechanisms of bronchiectasis, as well as improvements in computed tomography and the development of new pharmacological agents, might help to improve the clinical management of this chronic infective/inflammatory disorder.

Sheng Wu Gong Cheng Xue Bao, 2002 Jan, 18(1), 55 - 8
{Study on production of acrylamide by microbial method (I)--Culture of bacterium cells and expression of high activity of nitrile hydratase}; Chen Z et al.; The cultural conditions for the growth of Norcardia cell were studied in this paper . Controlling pH value, adding nutrient and optimizing the quantity of inducer during cultivation, the activity of nitrile hydratase reached 6567 u/mL (culture medium), which was the highest value appeared in native journals . In the farther hydratase experiments, no by-product, crylic acid, was detected . It showed that the activity of amidase was not promoted obviously while the activity of nitrile hydratase was increased greatly . The results set a strong foundation for the industrial application and the research on new technology.

Microb Ecol, 2002 Jul, 44(1), 49 - 58 Epub 2002 Apr 30.
The diversity and function of soil microbial communities exposed to different disturbances; Muller AK et al.; To improve understanding of the relationship between the diversity and function of the soil ecosystem, we investigated the effect of two different disturbances on soil bacterial communities -- long-term exposure to the heavy metal mercury and transient exposure to the antibiotic tylosin . In the mercury-contaminated soil the diversity (Shannon index) was reduced as assessed from denaturing gradient gel electrophoresis (DGGE) of amplified 16S rDNA sequences from the soil community DNA and from colony morphology typing of the culturable bacterial population . However, analysis of the substrate utilization profiles did not reveal any differences in diversity . In the tylosin-treated soil, DGGE revealed a small difference in the diversity of 16S rDNA compared to the control soil, whereas analysis of the colony morphology typing or substrate utilization results did not reveal any differences in diversity . Soil function was also affected by mercury contamination . The lag time before soil respiration increased following addition of glucose or alfalfa substrate was longer in the mercury-contaminated soil than in the control soil . Moreover, it was markedly prolonged in mercury-contaminated soil subjected to heat treatment prior to substrate addition, thus indicating reduced resistance to a new disturbance in the mercury-contaminated soil as compared to the control soil . Tylosin treatment did not have any significant effect on any of the respiration parameters measured, either with or without prior heat treatment of the soil.

Appl Environ Microbiol, 2002 May, 68(5), 2484 - 94
Effects of amendment with ferrihydrite and gypsum on the structure and activity of methanogenic populations in rice field soil; Lueders T et al.; Methane emission from paddy fields may be reduced by the addition of electron acceptors to stimulate microbial populations competitive to methanogens . We have studied the effects of ferrihydrite and gypsum (CaSO(4) . 2H(2)O) amendment on methanogenesis and population dynamics of methanogens after flooding of Italian rice field soil slurries . Changes in methanogen community structure were followed by archaeal small subunit (SSU) ribosomal DNA (rDNA)- and rRNA-based terminal restriction fragment length polymorphism analysis and by quantitative SSU rRNA hybridization probing . Under ferrihydrite amendment, acetate was consumed efficiently (<60 microM) and a rapid but incomplete inhibition of methanogenesis occurred after 3 days . In contrast to unamended controls, the dynamics of Methanosarcina populations were largely suppressed as indicated by rDNA and rRNA analysis . However, the low acetate availability was still sufficient for activation of Methanosaeta spp., as indicated by a strong increase of SSU rRNA but not of relative rDNA frequencies . Unexpectedly, rRNA amounts of the novel rice cluster I (RC-I) methanogens increased significantly, while methanogenesis was low, which may be indicative of transient energy conservation coupled to Fe(III) reduction by these methanogens . Under gypsum addition, hydrogen was rapidly consumed to low levels ( approximately 0.4 Pa), indicating the presence of a competitive population of hydrogenotrophic sulfate-reducing bacteria (SRB) . This was paralleled by a suppressed activity of the hydrogenotrophic RC-I methanogens as indicated by the lowest SSU rRNA quantities detected in all experiments . Full inhibition of methanogenesis only became apparent when acetate was depleted to nonpermissive thresholds (<5 microM) after 10 days . Apparently, a competitive, acetotrophic population of SRB was not present initially, and hence, acetotrophic methanosarcinal populations were less suppressed than under ferrihydrite amendment . In conclusion, although methane production was inhibited effectively under both mitigation regimens, different methanogenic populations were either suppressed or stimulated, which demonstrates that functionally similar disturbances of an ecosystem may result in distinct responses of the populations involved.

Eur J Pharm Biopharm, 2002 May, 53(3), 263 - 80
Ocular tolerance of preservatives and alternatives; Furrer P et al.; Eye drops are multiple dosage forms protected against microbial contamination by means of preservatives . However, the ocular tolerance of these chemicals can vary and this may result in adverse toxic or allergic reactions . This overview presents the pharmacopoeial requirements for the preservation of eye drops, the factors affecting ocular tolerance as well as the adverse external ocular effects induced by preservatives . The alternatives to the use of preservatives are also discussed, including the recent progress in eye drops packaging.

Am J Surg, 2002 Apr, 183(4), 464 - 70
Anatomic and functional characteristics of the rat ileal pouch; Chen CN et al.; BACKGROUND: The definitive operation for chronic ulcerative colitis (UC) and familial adenomatous polyposis is total proctocolectomy with ileal pouch-anal anastomosis (IPAA) . Mild inflammation (pouchitis) is omnipresent in pouches and becomes severe in 50% of UC patients with IPAA . The etiology of pouchitis is likely due to combined genetic, microbial, and immunologic factors . Epithelial cell exposure to surgical trauma and/or to changes in intestinal bacterial composition may account for the inflammatory infiltrate . Progress in understanding pouchitis is restricted by the lack of suitable animal models . METHODS: An ileal pouch-rectal anastomosis {IPRA} in rats was developed to reproduce a model of human IPAA and clinical, gross and histologic criteria were determined . RESULTS: Many shared features with human ileal pouch were observed . CONCLUSION: IPRA is an important in vivo model to study mechanisms of repair, defense and immunity that may contribute to pouchitis.

Heart Dis, 2001 Jul-Aug, 3(4), 270 - 5
Why do we reject grafts?
Carpenter CB.
One of the puzzles in clinical and experimental organ and tissue transplantation has been why it is that, with the exception of transplantation between genetically identical twin pairs, transplantation results in a rapidly progressing immune response to the point of tissue necrosis in a matter of a few days, even though the recipient has not been immunized to the donor . Indeed, the numbers of T lymphocytes predetermined to react against grafts are relatively abundant compared to those that recognize microbial antigens . Cellular, molecular, and genetic studies are now revealing the nature of T-cell recognition, and why it is that we cannot freely exchange tissue grafts.

AIHA J (Fairfax, Va), 2002 Mar-Apr, 63(2), 135 - 40
Determination of unique microbial volatile organic compounds produced by five Aspergillus species commonly found in problem buildings; Gao P et al.; This study identified unique microbial volatile organic compounds (UMVOCs) produced by five Aspergillus species (A . fumigatus, A . versicolor, A . sydowi, A . flavus, and A . niger) cultivated on malt extract agar and gypsum board . The hypothesis was that UMVOCs can be used to predict the presence of Aspergillus species . During the cultivation humidified air was continually supplied and evenly distributed through each of the culture flasks . Volatile metabolites were collected using Tenax TA tubes on Days 8, 16, and 30 after inoculation . The volatile metabolites were determined by gas chromatography/mass spectroscopy after thermal desorption . Nine compounds recognized as UMVOCs--3-methyl-1-butanol; 2-methyl-1-propanol; terpineol; 2-heptanone; 1-octen-3-ol; dimethyl disulfide; 2-hexanone; 3-octanone; and 2-pentylfuran--were found on the cultures in detectable amounts . The first two compounds were detected at the highest frequency when combining both media . The first four compounds were found to be the dominant UMVOCs on gypsum board, which could be used as chemical markers of the common Aspergillus species grown indoors.

J Org Chem, 2002 May 3, 67(9), 3015 - 21
Synthesis of optically active vicinal fluorohydrins by lipase-catalyzed deracemization; Wolker D et al.; Three microbial lipases have been used to deracemize trans-2-fluorocycloalkanols 2 both by hydrolysis of the corresponding acetates 3 or chloroacetates 4 and by esterification of the fluorohydrins 2 using vinyl acetate and vinyl chloroacetate, respectively . Pseudomonas cepacia lipase was the most selective for the six- and the seven-membered-ring compounds, while the lipase from Candida rugosa was most useful for the eight-membered-ring compounds . Both lipases transform the (R)-enantiomers preferentially . In contrast the lipase from Candida antarctica hydrolyzed the esters of trans-2-fluorocyclohexanol 2a and esterified the fluorohydrin itself with very low enantiopreference for the (R)-isomers . The seven- and the eight-membered ring esters and the corresponding fluorohydrins were also transformed with low, but reverse, enantioselectivity.

Rev Sci Tech, 2002 Apr, 21(1), 179 - 85
Area-wide biological control of disease vectors and agents affecting wildlife; Reichard RE; Two examples of area-wide programmes, employing the sterile insect technique (SIT), which have eradicated a parasite and a disease vector common to domestic and wild animals are described . New World screwworm (NWS), Cochliomyia hominivorax, caused significant morbidity and mortality of livestock and wild mammals in tropical and subtropical areas of America before eradication was achieved in North America using the SIT and other components of an integrated pest management (IPM) programme . Movement of wild as well as domestic animals from an area which is infested with screwworm to a free area requires prophylactic treatment . Tsetse fly-borne trypanosomosis has an immense influence on the distribution of people and livestock in Africa . The immunotolerance of wildlife to the parasites is an important factor in maintaining some areas livestock free as wildlife refuges . Slaughter has ceased of wild hoofstock species considered to be disease reservoirs for control purposes . The SIT, combined with other IPM measures, has resulted in the eradication of the tsetse fly and trypanosomosis from Zanzibar . Other programmes in Africa are underway . Microbial 'biopesticides' have also been employed successfully against plant insect pests and some vectors of human disease . It seems likely that for the immediate future, wildlife may benefit from area-wide biological control programmes, intended mainly to protect humans and/or domestic animals.

Trends Microbiol, 2002 May, 10(5), 232 - 7
Bacterial avoidance of phagocytosis; Celli J et al.; Phagocytosis constitutes the primary line of host innate and adaptive defence against incoming microbial pathogens, providing an efficient means for their removal and destruction . However, several virulent bacteria that do not function as intracellular pathogens have evolved mechanisms to avoid and prevent phagocytosis that constitute an essential part of their pathogenic capacity . Some of these mechanisms include preventing recognition by phagocytic receptors or blocking uptake by professional phagocytes . Recently, the molecular mechanisms of such antiphagocytic properties have been elucidated for some pathogens . Such mechanisms illustrate the diversity of mechanisms bacterial pathogens use to avoid phagocytic uptake.

Curr Opin Immunol, 2002 Jun, 14(3), 360 - 5
Influence of effector molecules on the CD8(+) T cell response to infection; Harty JT et al.; Expansion and contraction of antigen-specific CD8(+) T cells after infection or vaccination results in stable memory . Recent evidence demonstrates that anti-microbial effector molecules such as perforin and IFN-gamma regulate specific aspects of CD8(+) T cell homeostasis by mechanisms that may be dependent or independent of pathogen clearance.

J Appl Microbiol, 2002, 92(5), 860 - 5
Inactivation of Saccharomyces cerevisiae in solution by low-amperage electric treatment; Guillou S et al.; AIMS: The objectives of this study were to investigate the potential application of a low-amperage direct electric current as a non-thermal process for inactivation of Saccharomyces cerevisiae . METHODS AND RESULTS: Electric current was generated using a direct current power supply connected to a traditional electrochemical cell with two platinum electrodes immersed in conducting solution containing a population of S . cerevisiae . This treatment provoked inactivation of the yeast cells . The microbial destruction illustrated by D-values calculated from survival curves was shown to be proportional to the current amperage (i) (D varies from 1547 min to 140 min when i varies from 0.1 to 1 A, respectively) . The efficacy of the treatment was shown to be better at pH < 7 . Statistical analysis showed no significant effect (P > 0.05) of ionic strength on yeast lethality induced by electrolysis . CONCLUSIONS: The lethal effect of the electric treatment on S . cerevisiae in phosphate buffer was shown to be due to neither ohmic heating nor toxic hydrogen peroxide . A synergistic effect of temperature and electrolysis was observed when the temperature became lethal for the yeast . SIGNIFICANCE AND IMPACT OF THE STUDY: The method described for yeast lethality induced by electrolysis has potential for soft sterilization, particularly when combined with the synergistic effect of moderate heat.

Jpn J Infect Dis, 2002 Feb, 55(1), 23 - 6
Evaluation of a sentinel surveillance system for influenza, 1995-2000, Kyoto City, Japan; Fujii H et al.; We compared a municipal sentinel surveillance system for influenza with the Microbial Isolation Surveillance System (MISS) in Kyoto City, Japan . Sensitivity, specificity, and predictive value positive (PVP) of the Influenza Sentinel Surveillance System (ISSS) compared to the MISS were calculated by influenza season and by month . Sensitivity ranged from 80 to 97%, specificity ranged from 55 to 77%, and PVP ranged from 29 to 52% by season (P < 0.001) . On the other hand, sensitivity ranged from 86 to 100%, specificity ranged from 38 to 66%, and PVP ranged from 31 to 50% by month (P < 0.001) . Specificity was calculated as 93% in November . The sensitivity of ISSS was found to be sufficient regardless of the magnitude of influenza activity . Specificity varied by season, indicating the difficulty of clinically diagnosing other respiratory illnesses . The PVP remained at less than 50% before and after the influenza seasons and it varied year by year . In general, the ISSS is a good surveillance system for monitoring influenza activity.

Int J Environ Health Res, 2002 Mar, 12(1), 93 - 8
Indoor biological contaminants and symptoms of sick building syndrome in office buildings in Mauritius; Bholah R et al.; This study was carried out to investigate possible relationship between bio-contaminants and symptoms of sick building syndrome among office workers in Mauritius . Viable microbial colonies were collected using a Casella slit sampler in 23 selected indoor office buildings . A questionnaire survey as well as a walk through investigation was undertaken . Physico-chemical measurements were also monitored in the selected offices . Results of this study showed that number of indoor bacterial bioaerosol concentrations ranged between 3 and 1110 CFU/m(3) while fungal counts were 0-196 CFU/m(3) . However, most of the buildings showed absence of dust mites . In conclusions fungal contamination was found to be associated with the onset of sick building syndrome symptoms among workers in office buildings in Mauritius.

Phys Rev E Stat Phys Plasmas Fluids Relat Interdiscip Topics, 1999 Nov, 60(5 Pt B), 5932 - 7
Statistics of DNA sequences: a low-frequency analysis; de Sousa Vieira M; We study statistical properties of DNA chains of thirteen microbial complete genomes . We find that the power spectrum of several of the sequences studied flattens off in the low frequency limit . This implies the correlation length in those sequences is much smaller than the entire DNA chain . Consequently, in contradiction with previous studies, we show that the fractal behavior of DNA chains does not always prevail through the entire DNA molecule.

Nippon Rinsho, 2002 Apr, 60(4), 669 - 73
{HIV-suppressive factors}; Moriuchi H et al.; A number of host and microbial factors have been shown to modulate HIV-1 infection . Their inhibitory effects are either HIV-specific or non-specific, and involve many different kinds of mechanisms . Among anti-HIV host factors are natural ligands or natural antibodies to HIV coreceptors, anti-inflammatory cytokines, interferons and several body fluid components (such as lactoferrin and prostaglandins) . Microbial pathogens/factors that may suppress HIV-1 infection include lipopolysaccharide, scrub-typhus rickettsia, human herpesviruses-6 or -7, and GB virus C . While simple application of these HIV-suppressive factors for HIV-infected individuals is not realistic, investigation of mechanisms involved may lead to better understanding of HIV pathogenesis and help establish novel anti-HIV strategy.

Lett Appl Microbiol, 2002, 34(5), 359 - 64
Histopathological methods for the investigation of microbial communities associated with disease lesions in reef corals; Bythell JC et al.; AIMS: To determine the spatial structure of microbial communities associated with disease lesions of reef corals (Scleractinia) . METHODS AND RESULTS: Agarose pre-embedding preserved the structure of the disease lesion and surrounding tissues prior to demineralization of the carbonate exoskeleton and embedding in resin . Fluorescence in situ hybridization (FISH) was used to localize bacteria in the lesions of various diseases . CONCLUSIONS: The techniques successfully preserved the in situ spatial structure of degenerated coral tissues . In one case (white plague disease), significant bacterial populations were found only in fragmented remnants of degenerated coral tissues at the lesion boundary that would not have been detected using conventional histopathological techniques . SIGNIFICANCE AND IMPACT OF THE STUDY: Determining the composition, spatial structure and dynamics of microbial communities within the disease lesions is necessary to understand the process of disease progression . The methods described may be applicable to a wide range of diseases involving necrotic lesion formation and requiring extensive tissue processing, such as skeleton demineralization.

J Appl Microbiol, 2002, 92(4), 764 - 75
Evolution of extracellular enzyme activities during manure composting; Tiquia SM; AIMS: The objectives of this work were to determine the extracellular enzyme profiles during composting, relate the activities of these enzymes to the changes in microbial population and compare the enzyme profiles between two manures . METHODS AND RESULTS: API ZYM assay was used to monitor the activities of 19 extracellular enzymes during poultry and pig manure composting . Results showed an overall increase in diversity and relative abundance of enzymes present . The relative abundance and activities of enzymes were higher in poultry manure than in pig manure . Among the 19 enzymes tested, esterase, valine amino-peptidase and alpha-galactosidase were the most abundant enzymes in poultry manure, whereas it was N-acetyl-beta-glucosaminidase for the pig manure . A number of these enzymes correlated with change in numbers of different microbial groups during composting . CONCLUSIONS: The composting process represented a combined activity of a wide succession of environments, as one enzyme/microbial group overlapped the other and each emerged gradually due to the continual change in temperature and progressive breakdown of complex compounds to simpler ones . SIGNIFICANCE AND IMPACT OF THE STUDY: The results presented here show the applicability of the API ZYM test not only in monitoring the quantitative and qualitative fluctuation of the available substrate during composting, but also in revealing differences in composts and compost maturity.

Curr Opin Infect Dis, 2001 Jun, 14(3), 295 - 300
The role of colostral antibodies in prevention of microbial infections; Lilius EM et al.; Mammalian colostrum offers passive protection to the newborn against a variety of microbial pathogens, in the form of specific immunoglobulin A, G and M antibodies . Sharing maternal immunological memory is in many cases vital for the infant, but may have disastrous consequences, such as involuntary transfer of disease and disturbance of the developing immune system . In most published studies, immune milk preparations are reported to be effective in the prevention of various gastroenteric infections, but not in the treatment of an established infection.

Curr Opin Infect Dis, 2000 Jun, 13(3), 221 - 226
The role of interleukin-10 in critical illness; Opal SM et al.; Interleukin-10 is the most potent anti-inflammatory cytokine yet identified . It has multiple actions affecting the innate immune system as well as humoral and cellular immune responses . It occupies a pivotal role in the regulation of the immune response to microbial pathogens in health and disease . Knowledge gained in the molecular biology of IL-10 and its complex immune effects in experimental infection models are leading to new insights into therapeutic manipulation of IL-10 in patients with systemic inflammatory diseases.

Curr Opin Allergy Clin Immunol, 2002 Apr, 2(2), 141 - 5
Endotoxin, atopy and asthma; Holla AD et al.; Endotoxin is infamous for its ability to exacerbate existing allergy and asthma symptoms . Current research supports this phenomenon, demonstrating its significance in the home, as well as in the workplace . At the same time, evidence is emerging that exposure to endotoxin may drive immune development away from the T-helper lymphocyte type 2-mediated allergy and asthma profile . This fits in nicely with the 'hygiene hypothesis', which attributes the past century's rise in allergy and asthma to a reduction in microbial burden . Indeed, infections have been associated with less atopy and asthma . Recent investigations have suggested that naturally-occurring non-infectious exposure to microbial components such as endotoxin might mitigate atopy and asthma as well.

Curr Opin Allergy Clin Immunol, 2001 Dec, 1(6), 545 - 8
Primary prevention of atopic asthma; Bjorksten B; Current recommendations given for primary prevention of allergic asthma often include advice on how to reduce exposure to inhalant allergens early in life . There is little support for such advice, however . On the contrary, recent studies indicate that extensive allergen exposure may actually reduce the likelihood of developing allergic asthma . However, recent studies indicate possible future venues for primary allergy prevention through immune modulation . This may possibly be achieved by stimulating the maturation of the immune system early in life by altering the microbial gut flora or by recently developed immunomodulatory Th2 antagonists . In the meantime, the avoidance of exposure to tobacco smoke remains the only recommendation that is reasonably well documented by evidence-based medicine, while allergen avoidance in primary prevention is not.

Curr Opin Allergy Clin Immunol, 2001 Jun, 1(3), 237 - 41
Sensitization and tolerance; Husby S; The mechanisms responsible for sensitization, in particular within the gastrointestinal tract, are IgE-mediated as well as of a non-IgE-mediated, immunological origin . The phenomenon that is the opposite of sensitization is the maintenance of tolerance and is exemplified by the phenomenon 'oral tolerance' . The cytokines transforming growth factor beta and interferon gamma have been shown to be key immunoregulatory cytokines in oral tolerance . A new experimental model of eosinophilic allergic gastroenteritis has been developed with the use of encapsulated dietary antigen . The model was used in mice with genetic deletions of the eosinophil chemokine eotaxin or of the cytokine IL-5, demonstrating the importance of eotaxin . In clinical allergy research, a major question has been to explain the global increase in asthma and allergy . The 'hygiene hypothesis' states that a lack of maturation of the infant immune system from a T helper 2 to a T helper 1 type of immune response may be caused by less microbial stimulation in Western societies . Several lines of data support this hypothesis . However, apart from the genetic constitution of the individual, breastfeeding in infancy may be the most important single determinant for the development of clinical tolerance.

Curr Opin Allergy Clin Immunol, 2001 Feb, 1(1), 73 - 8
T-cell responses in allergy and asthma; Romagnani S; T-helper-2-type cytokines and some chemokines play an essential role in the pathogenesis of both allergy and asthma . A change in the T-helper 1/T-helper 2 balance, caused by the dramatic change in the microbial environment of children, may account for the increasing prevalence of these conditions, but can also provide a conceptual basis for the development of new therapeutic strategies.

Science, 2002 Apr 19, 296(5567), 490 - 4
Allergy, parasites, and the hygiene hypothesis; Yazdanbakhsh M et al.; The increase of allergic diseases in the industrialized world has often been explained by a decline in infections during childhood . The immunological explanation has been put into the context of the functional T cell subsets known as T helper 1 (TH1) and T helper 2 (TH2) that display polarized cytokine profiles . It has been argued that bacterial and viral infections during early life direct the maturing immune system toward TH1, which counterbalance proallergic responses of TH2 cells . Thus, a reduction in the overall microbial burden will result in weak TH1 imprinting and unrestrained TH2 responses that allow an increase in allergy . This notion is contradicted by observations that the prevalence of TH1-autoimmune diseases is also increasing and that TH2-skewed parasitic worm (helminth) infections are not associated with allergy . More recently, elevations of anti-inflammatory cytokines, such as interleukin-10, that occur during long-term helminth infections have been shown to be inversely correlated with allergy . The induction of a robust anti-inflammatory regulatory network by persistent immune challenge offers a unifying explanation for the observed inverse association of many infections with allergic disorders.

Blood, 2002 May 1, 99(9), 3263 - 71
Type I interferons produced by dendritic cells promote their phenotypic and functional activation; Montoya M et al.; Resting dendritic cells (DCs) are resident in most tissues and can be activated by environmental stimuli to mature into potent antigen-presenting cells . One important stimulus for DC activation is infection; DCs can be triggered through receptors that recognize microbial components directly or by contact with infection-induced cytokines . We show here that murine DCs undergo phenotypic maturation upon exposure to type I interferons (type I IFNs) in vivo or in vitro . Moreover, DCs either derived from bone marrow cells in vitro or isolated from the spleens of normal animals express IFN-alpha and IFN-beta, suggesting that type I IFNs can act in an autocrine manner to activate DCs . Consistent with this idea, the ability to respond to type I IFN was required for the generation of fully activated DCs from bone marrow precursors, as DCs derived from the bone marrow of mice lacking a functional receptor for type I IFN had reduced expression of costimulatory and adhesion molecules and a diminished ability to stimulate naive T-cell proliferation compared with DCs derived from control bone marrow . Furthermore, the addition of neutralizing anti-IFN-alpha/beta antibody to purified splenic DCs in vitro partially blocked the "spontaneous" activation of these cells, inhibiting the up-regulation of costimulatory molecules, secretion of IFN-gamma, and T-cell stimulatory activity . These results show that DCs both secrete and respond to type I IFN, identifying type I interferons as autocrine DC activators.

Int Immunopharmacol, 2002 Mar, 2(4), 545 - 55
Chalcones from Chinese liquorice inhibit proliferation of T cells and production of cytokines; Barfod L et al.; Licochalcone A (LicA), an oxygenated chalcone, has been shown to inhibit the growth of both parasites and bacteria . In this study, we investigated the effect of LicA and four synthetic analogues on the activity of human peripheral blood mononuclear cell proliferation and cytokine production . Four out of five chalcones tested inhibited the proliferation of lymphocytes measured by thymidine incorporation and by flow cytometry . The production of pro- and anti-inflammatory cytokines from monocytes and T cells was also inhibited by four of five chalcones . Furthermore, intracellular detection of cytokines revealed that the chalcones inhibited the production rather than the release of the cytokines . Taken together, these results indicate that LicA and some analogues may have immunomodulatory effects, and may thus be candidates not only as anti-microbial agents, but also for the treatment of other types of diseases.

Food Addit Contam, 2002 Apr, 19(4), 379 - 86
Structural characterization of metabolites after the microbial degradation of type A trichothecenes by the bacterial strain BBSH 797; Fuchs E et al.; Contamination of feed with trichothecenes, a group of Fusarium mycotoxins, leads to losses in performance due to their immunosupressive effects and the negative effect on the gastrointestinal system in animal production . A possible way of detoxification is microbial degradation, which was the focus of this study . A bacterial strain--BBSH 797--which can degrade some mycotoxins of the trichothecene group, has already been isolated . It transforms deoxynivalenol (DON) into its metabolite DOM-1, the non-toxic deepoxide of DON . Analogous to the microbial degradation of DON, the transformation of six different type A trichothecenes was observed . The metabolites appearing were characterized by GC-MS after derivatization with TRI-SIL TBT . Two metabolites were additionally, identified by liquid chromatography-mass spectrometry with particle beam interface (LC-PB-MS) with electron impact (EI)-ionization mode . The major finding was that scirpentriol was completely transformed into its non-toxic metabolite deepoxy scirpentriol, while the mycotoxin T-2 triol underwent a more complicated metabolism . According to the study, T-2-triol was degraded into its non-toxic deepoxy form and into T-2 tetraol, which was then further metabolized to deepoxy T-2 tetraol . GC-MS after derivatization with TRI-SIL TBT was suitable for the structural characterization of trichothecenes and their degradation products . Besides the mass spectra of already known degradation products, spectra of new metabolites could be recorded by LC-PB-MS.

Prikl Biokhim Mikrobiol, 2002 Mar-Apr, 38(2), 208 - 12
{Changes in macromolecular characteristics and biological activity of hydrolytic lignin hydrolysate in the course of composting}; Novikova LN et al.; Composting of hydrolytic lignin by a microbial association changed its molecular-weight composition, acid-based properties, and supramolecular structure . Specifically, by the end of the third month of composting, an increase was observed in its exchange capacity and the amount of negative charges, as well as in the content of phenyl, hydroxyl, and carboxyl groups . The use of this compost as a fertilizer for barley growth demonstrated that the changes increased the biological activity of hydrolytic lignin.

Biosens Bioelectron, 2002 Jun, 17(6-7), 495 - 501
On-line microbial biosensing and fingerprinting of water pollutants; Horsburgh AM et al.; The potential for biosensors to contribute to on-line toxicity testing for monitoring of water quality is currently constrained both by the relevance of the biosensors available and the technology for biosensor delivery . This paper reports the use of novel slow release biosensor delivery for on-line monitoring instrumentation, with environmentally relevant bacteria for both simple toxicity testing and more complex toxicity fingerprinting of industrial effluents . The on-line toxicity test, using bioluminescence-based biosensors, proved to be as sensitive and reliable as the corresponding batch test, with comparable contaminant EC(50) values from both methods . Toxicity fingerprinting through the investigation of the kinetics (dose-response) and the dynamics (response with time) of the biosensor test response proved to be diagnostic of both effluent type and composition . Furthermore, the slow release of biosensors immobilised in a polyvinyl alcohol (PVA) matrix greatly improved biosensor delivery, did not affect the sensitivity of toxicity testing, and demonstrated great potential for inclusion in on-line monitoring instrumentation.

FEMS Microbiol Lett, 2002 Feb 5, 207(2), 173 - 7
Characterization of Azotobacter vinelandii aggregation in submerged culture by digital image analysis; Pena C et al.; A simple and accurate method for determining the distribution of sizes of single cells and aggregates of Azotobacter vinelandii by image analysis has been developed . A staining procedure using methylene blue helps to enhance the contrast between aggregates and background without altering aggregate size distribution . Sample dilution affected the distribution of the population and therefore should be avoided . Mixing and aeration conditions during culture play an important role in the aggregation of A . vinelandii . Cells grown under mild mixing conditions (unbaffled flasks) presented a thick slime layer and formed aggregates of up to 35 microm of average equivalent diameter . In contrast, under strong agitation conditions (baffled flasks) practically no aggregates were formed throughout cultivation . The method described can be used for the characterization of aggregation of other microbial cultures.

J Agric Food Chem, 2002 Apr 24, 50(9), 2666 - 72
Functional properties of oat globulin modified by a calcium-independent microbial transglutaminase; Siu NC et al.; Oat globulin was modified by a calcium-independent microbial transglutaminase (TG) . The TG-polymerized protein had higher solubility than the control at acidic pH and had improved water- and fat-binding properties . Incubation of 10% (w/v) oat globulin dispersions in the presence of TG at 37 degrees C led to the formation of a well-developed viscoelastic gel network with a microstructure characterized by thick strands and large clusters . The TG-induced gels had higher modulus values, lower loss tangent values, and lower frequency dependency than the heat-induced gels . The TG-induced gel system has the characteristics of classical polymer gel with permanent "chemical" cross-links, whereas the heat-denatured system has the characteristics of a temporary "physical" gel with breakable cross-links . Fourier transform infrared spectroscopy showed marked shift and intensity changes in several major bands, suggesting pronounced changes in protein conformation during TG-induced gelation . Aggregation of protein molecules was also indicated by the progressive increases in two infrared bands (1679-1682 and 1622-1625 cm(-)(1)) associated with the formation of intermolecular beta-sheets and strands . Results suggest that new food polymers with unique functionality can be produced from oat globulin treated with TG and that elastic gels can be formed near neutral pH, instead of the alkaline pH required for thermally induced oat globulin gels.

J Agric Food Chem, 2002 Apr 24, 50(9), 2660 - 5
Physicochemical and structural properties of oat globulin polymers formed by a microbial transglutaminase; Siu NC et al.; Oat globulin was polymerized by a microbial transglutaminase (TG), and some physicochemical and functional properties of polymers were studied . Reversed-phase HPLC revealed that the number of epsilon-(gamma-glutamyl) lysine isopeptide bonds formed after 4 h of enzyme incubation was 2.21 micromol/g of protein . SDS-PAGE showed that the oat globulin acidic polypeptides (AP) were more susceptible to polymerization than the basic polypeptides (BP), and the reactivities of both AP and BP were enhanced by the addition of other substrate proteins . Differential scanning calorimetry showed that both the denaturation temperature and denaturation enthalpy were decreased after TG treatment . Fourier transform infrared spectroscopy revealed marked increases in the intensity of two intermolecular beta-sheet bands associated with aggregate formation but little conformational changes in the polymerized protein . TG incubation led to progressive changes in flow properties of oat globulin dispersions, indicating enhanced pseudoplasticity and increased viscosity and yield stress.

J Agric Food Chem, 2002 Apr 24, 50(9), 2607 - 14
Effect of soil moisture and sample depth on pesticide photolysis; Frank MP et al.; The effects of soil depth and moisture on pesticide photolysis were studied . Moist soil at depths of 3, 2.5, 2, 1.5, 1, and 0.5 mm were each dosed at 2.5 microg/g with (14)C-niclosamide and photolyzed under a xenon lamp at constant temperature . Samples were removed after 20, 40, 110, and 153 h of continuous irradiation . The decrease in percent of niclosamide and the appearance of degradates were followed by analyzing the soil extracts by HPLC . A corresponding set of experiments used air-dried soil . An experiment was also performed using initially moist soil which was permitted to dry during photolysis but returned to moist conditions at each sampling . Qualitative and quantitative differences were found in the rate and route of degradation of niclosamide under these conditions . These differences have resulted from a combination of reduced photochemical activity and microbial population in dry soil . The half-lives of niclosamide in the dry soils were 2 to 5 times longer than those in the moisture-maintained soil . There was also a noticeable difference in the half-lives in soil of different depths . Moisture-maintained soil showed a uniform linear increase in half-life from 95 to 195 h as soil depth increased from 0.5 mm to 3.0 mm . With air-dried soil the half-lives were greatly dependent on soil depth, showing a much broader range of 199 h at 0.5-mm to 1064 h in 3.0-mm soil . An experimental design is described which maintains soil temperature and moisture to preset conditions.

J Agric Food Chem, 2002 Apr 24, 50(9), 2565 - 70
Effects of storage conditions on furocoumarin levels in intact, chopped, or homogenized parsnips; Ostertag E et al.; Furocoumarins represent a family of natural food constituents with phototoxic and photomutagenic properties . They are found mainly in plants belonging to the Rutaceae and Umbilliferae such as celery, carrots, and parsnips . Parsnips (Pastinaca sativa L.) have become more and more popular as a vegetable, e.g., as a constituent of or ingredient in baby food . Previous work has shown that microbial infection of parsnip roots can result in a dramatic increase in furocoumarin levels . In this study, freshly harvested parsnips were stored as whole roots, pieces (cubes), or homogenate at +4 degrees C or -18 degrees C over various time periods under standard conditions . It was found that furocoumarin concentrations (sum of five furocoumarins: angelicin, isopimpinellin, 5-methoxypsoralen, 8-methoxypsoralen, and psoralen) in freshly harvested parsnips, analyzed by HPLC after extraction with diethyl ether and sequential solid phase (reversed-phase and silica) extraction, was generally lower than 2.5 mg/kg, and storage of parsnips in any form investigated at -18 degrees C over up to 50 days did not lead to a marked increase in furocoumarin levels . In contrast, storage of whole parsnips, but not of cubes or homogenate, at +4 degrees C resulted in a marked biphasic increase of furocoumarin concentrations after 7 and 38 days of storage up to levels of about 40 mg/kg . A dramatic increase in furocoumarin concentrations up to 566 mg/kg was observed when whole parsnips obtained from the market were kept at room temperature over 53 days, resulting in a visible microbial (mold) infection . Baby food products from the German market containing parsnips as an ingredient or constituent showed furocoumarin levels < or =0.41 mg/kg, suggesting that properly stored roots/preparations have been used . It is recommended that, after harvesting, parsnips be kept at -18 degrees C or under other conditions that prevent microbial infections.

Crit Rev Biotechnol, 2002, 22(1), 33 - 64
Biotechnology of microbial xylanases: enzymology, molecular biology, and application; Subramaniyan S et al.; Xylanases are hydrolases depolymerizing the plant cell wall component xylan, the second most abundant polysaccharide . The molecular structure and hydrolytic pattern of xylanases have been reported extensively and the mechanism of hydrolysis has also been proposed . There are several models for the gene regulation of which this article could add to the wealth of knowledge . Future work on the application of these enzymes in the paper and pulp, food industry, in environmental science, that is, bio-fueling, effluent treatment, and agro-waste treatment, etc . require a complete understanding of the functional and genetic significance of the xylanases . However, the thrust area has been identified as the paper and pulp industry . The major problem in the field of paper bleaching is the removal of lignin and its derivatives, which are linked to cellulose and xylan . Xylanases are more suitable in the paper and pulp industry than lignin-degrading systems.

J Biol Chem, 2002 Jun 21, 277(25), 22453 - 9 Epub 2002 Apr 15.
Complementation of pulmonary abnormalities in SP-D(-/-) mice with an SP-D/conglutinin fusion protein; Zhang L et al.; Surfactant protein D (SP-D) and serum conglutinin are closely related members of the collectin family of host defense lectins . Although normally synthesized at different anatomic sites, both proteins participate in the innate immune response to microbial challenge . To discern the roles of specific domains in the function of SP-D in vivo, a fusion protein (SP-D/Cong(neck+CRD)) consisting of the NH(2)-terminal and collagenous domains of rat SP-D (rSP-D) and the neck and carbohydrate recognition domains (CRDs) of bovine conglutinin (Cong) was expressed in the respiratory epithelium of SP-D gene-targeted (SP-D(-/-)) mice . While SP-D/Cong(neck+CRD) fusion protein did not affect lung morphology and surfactant phospholipid levels in the lungs of wild type mice, the chimeric protein substantially corrected the increased lung phospholipids in SP-D(-/-) mice . The SP-D/Cong(neck+CRD) fusion protein also completely corrected defects in influenza A clearance and inhibited the exaggerated inflammatory response that occurs following viral infection . However, the chimeric protein did not ameliorate the ongoing lung inflammation, enhanced metalloproteinase expression, and alveolar destruction that characterize this model of SP-D deficiency . By contrast, a single arm mutant (RrSP-D(Ser15,20)) partially restored antiviral activity but otherwise failed to rescue the deficient phenotype . Our findings directly implicate the CRDs of both SP-D and conglutinin in host defense in vivo . Our findings also strongly suggest that the molecular mechanisms underlying impaired pulmonary host defense and abnormal lipid metabolism are distinct from those that promote ongoing inflammation and the development of emphysema.

Zhonghua Yan Ke Za Zhi, 2002 Jan, 38(1), 21 - 3
{Retrospective analysis of misdiagnosed amoebic keratitis}; Li S et al.; OBJECTIVE: To analyze the clinical characteristic of amoebic keratitis and the cause of misdiagnosis retrospectively . METHODS: Corneal pathological sections of 269 cases having been diagnosed as herpes simplex keratitis (HSK), bacterial keratitis and other microbial keratitis and then undergone penetrating keratoplasty (PKP) were reexamined to find the misdiagnosed cases of amoebic keratitis . The clinical characteristic efficacy of treatment and cause of misdiagnosis were retrospectively analyzed according to case history and photographs . RESULTS: Based on the pathological examination, 5 cases of amoebic keratitis were recognized which had been misdiagnosed, including HSK in 3 cases, fungal keratitis in 1 case and suppurative keratitis in 1 case previously . The main clinical characteristics were severe radiating neuralgia and ring-shaped stromal infiltrates . After PKP, infection of 3 cases were controlled, 2 cases were recurrent and underwent eyeball enucleation eventually . CONCLUSION: The incidence of amoebic keratitis is not very low in China . It is necessary to pay high attention to this kind of disease, and its early and definite diagnosis is very important for the prevention of serious results.

Microb Ecol, 2002 May, 43(4), 424 - 31 Epub 2002 Apr 15.
Anaerobic biooxidation of Fe(II) by Dechlorosoma suillum; Lack JG et al.; Anaerobic microbial oxidation of Fe(II) was only recently discovered and very little is known about this metabolism . We recently demonstrated that several dissimilatory perchlorate-reducing bacteria could utilize Fe(II) as an electron donor under anaerobic conditions . Here we report on a more in-depth analysis of Fe(II) oxidation by one of these organisms, Dechlorosoma suillum . Similarly to most known nitrate-dependent Fe(II) oxidizers, D . suillum did not grow heterotrophically or lithoautotrophically by anaerobic Fe(II) oxidation . In the absence of a suitable organic carbon source, cells rapidly lysed even though nitrate-dependent Fe(II) oxidation was still occurring . The coupling of Fe(II) oxidation to a particular electron acceptor was dependent on the growth conditions of cells of D . suillum . As such, anaerobically grown cultures of D . suillum did not mediate Fe(II) oxidation with oxygen as the electron acceptor, while conversely, aerobically grown cultures did not mediate Fe(II) oxidation with nitrate as the electron acceptor . Anaerobic washed cell suspensions of D . suillum rapidly produced an orange/brown precipitate which X-ray diffraction analysis identified as amorphous ferric oxyhydroxide or ferrihydrite . This is similar to all other identified nitrate-dependent Fe(II) oxidizers but is in contrast to what is observed for growth cultures of D . suillum, which produced a mixed-valence Fe(II)-Fe(III) precipitate known as green rust . D . suillum rapidly oxidized the Fe(II) content of natural sediments . Although the form of ferrous iron in these sediments is unknown, it is probably a component of an insoluble mineral, as previous studies indicated that soluble Fe(II) is a relatively minor form of the total Fe(II) content of anoxic environments . The results of this study further enhance our knowledge of a poorly understood form of microbial metabolism and indicate that anaerobic Fe(II) oxidation by D . suillum is significantly different from previously described forms of nitrate-dependent microbial Fe(II) oxidation.

Microb Ecol, 2002 May, 43(4), 467 - 81 Epub 2002 Apr 15.
Abundance and biomass of heterotrophic flagellates, and factors controlling their abundance and distribution in sediments of Botany Bay; Lee WJ et al.; The abundance and biomass of heterotrophic flagellates were estimated monthly in sediments of Botany Bay during March 1999-February 2000 . The annual abundance and biomass were in the ranges of 0.46-4.70 x 10(5) cells/cm(3) and of 0.30-8.61 micro g C/cm(3), respectively . The majority of heterotrophic flagellates (93-100%) were less than 10 mm in length and few flagellates were larger than 10 mm . Of the total microbial carbon biomass, heterotrophic flagellates made up about 5% (but at times up to 35%) . The contribution of heterotrophic flagellates varied from month to month, and among the sites . The abundance of heterotrophic flagellates was negatively correlated with sediment grain size and positively correlated with the abundance of bacteria, algae (autotrophic flagellates and diatoms), and their probable grazers . A best subsets regression analysis showed that bacterial and algal abundance are the most important factors controlling the abundance of heterotrophic flagellates . When the previously reported grazing rates on bacteria were applied, heterotrophic flagellates would consume a maximum of 64% of bacterial standing stock daily in Botany Bay, suggesting that heterotrophic flagellates are important as bacterivores . However, the importance of heterotrophic flagellate grazing probably varies significantly among the sites and from month to month.

Microb Ecol, 2002 May, 43(4), 397 - 407 Epub 2002 Apr 15.
Microbial diversity and activity along the forefields of two receding glaciers; Sigler WV et al.; Forefields of two receding glaciers were sampled along either a 150 or 200 m long transect at identical spatial intervals for assessment of soil microbial activity and community diversity trends . The forefields belonged to the Dammaglacier (forefield area is 157 ha, 2000 m above sea level) and Rotfirnglacier (100 ha, 2200 m) and at the time of sampling were receding at an estimated rate of 8 and 10 m yr(-1) over the past 5 years, respectively . Direct counting of bacteria (DAPI staining), assessment of dehydrogenase activity (DH), and fluorescein diacetate hydrolysis activity (FDA) were performed to estimate bacteria number and soil microbial activity . Along the Dammaglacier forefield (from youngest to oldest soil), bacteria number (8.21 x 10(7) to 1.49 x 10(9) cells g(-1) soil), DH activity (0 to 61 mg TTC reduced g(-1) soil h(-1)), and FDA activity (0 to 100 mg fluorescein produced g-1 soil h-1) increased, suggesting the development of microbial populations increasing in number and activity . The Rotfirn forefield exhibited similar trends per gram of soil in bacteria number (1.13 x 10(8) to 5.93 x 10(9) cells), DH activity (0 to 36 mg TTC reduced), and FDA activity (2 to 70 mg fluorescein produced), but with more variability among samples than the Damma forefield samples . Molecular assessment of bacterial diversity included denaturing gradient gel electrophoresis (DGGE) and ribosomal intergenic spacer analysis (RISA) of soil DNA . DGGE and RISA revealed that the composition and succession of bacterial populations were different in both forefields . Comparison of Shannon diversity index values indicated that all populations sampled from the Damma forefield were significantly different (p < 0.05) . Conversely, similar populations existed in the Rotfirn forefield succession . Overall, the results indicate that diverse bacterial assemblages increasing in number and activity characterize these glacier forefield soils with both forefield successions exhibiting differing modes of bacterial community establishment.

Gut, 2002 May, 50 Suppl 3, III9 - 14
Toxins and the gut: role in human disease; Fasano A; Bacterial enteric infections exact a heavy toll on the human population, particularly among children . Despite the explosion of knowledge on the pathogenesis of enteric diseases experienced during the past decade, the number of diarrhoeal episodes and human deaths reported worldwide remains of apocalyptic dimensions . However, our better understanding of the pathogenic mechanisms involved in the onset of diarrhoea is finally leading to preventive interventions, such as the development of enteric vaccines, that may have a significant impact on the magnitude of this human plague . The application of a multidisciplinary approach to study bacterial pathogenesis, along with the recent sequencing of entire microbial genomes, have made possible discoveries that are changing the way scientists view the bacterium-host interaction . Today, research on the molecular basis of the pathogenesis of infective diarrhoeal diseases of necessity transcends established boundaries between microbiology, cell biology, intestinal pathophysiology, and immunology . This review focuses on the most recent outcomes of this multidisciplinary effort.

J Food Prot, 2002 Apr, 65(4), 673 - 6
Effect of irrigation method on transmission to and persistence of Escherichia coli O157:H7 on lettuce; Solomon EB et al.; In this study, the transmission of Escherichia coli O157:H7 to lettuce plants through spray and surface irrigation was demonstrated . For all treatments combined, the number of plants testing positive following a single exposure to E . coli O157: H7 through spray irrigation (29 of 32 plants) was larger than the number testing positive following surface irrigation (6 of 32 plants) . E . coli O157:H7 persisted on 9 of 11 plants for 20 days following spray irrigation with contaminated water . Immersion of harvested lettuce heads for 1 min in a 200 ppm chlorine solution did not eliminate all E . coli O157:H7 cells . The results of this study suggest that regardless of the irrigation method used, crops can become contaminated; therefore, the irrigation of food crops with water of unknown microbial quality should be avoided.

Curr Opin Biotechnol, 2002 Apr, 13(2), 117 - 23
Recombinant protein expression for therapeutic applications; Andersen DC et al.; In recent years, the number of recombinant proteins used for therapeutic applications has increased dramatically . Many of these applications involve complex glycoproteins and antibodies with relatively high production needs . These demands have driven the development of a variety of improvements in protein expression technology, particularly involving mammalian and microbial culture systems.

Photochem Photobiol, 2002 Mar, 75(3), 266 - 71
Seasonal fluctuation of DNA photodamage in marine plankton assemblages at Palmer Station, Antarctica; Meador J et al.; Ultraviolet radiation-induced DNA damage frequencies were measured in DNA dosimeters and natural plankton communities during the austral spring at Palmer Station, Antarctica, during the 1999-2000 field season . We found that the fluence of solar ultraviolet-B radiation (UV-B) at the earth's surface correlated with stratospheric ozone concentrations, with significant ozone depletion observed because of "ozone hole" conditions . To verify the interdependence of ozone depletion and DNA damage in natural microbial communities, seawater was collected daily or weekly from Arthur Harbor at Palmer Station, Antarctica, throughout "ozone season," exposed to ambient sunlight between 0600 and 1800 h and fractionated using membrane filtration to separate phytoplankton and bacterioplankton populations . DNA from these fractions was isolated and DNA damage measured using radioimmunoassay . Under low-ozone conditions cyclobutane dimer concentrations in bacterioplankton and phytoplankton communities were maximal . DNA damage measured in dosimeters correlated closely with ozone concentrations and UV-B fluence . Our studies offer further support to the theory that stratospheric deozonation is detrimental to marine planktonic organisms in the Southern Ocean.

Curr Top Med Chem, 2002 Mar, 2(3), 289 - 302
RNA and RNA-protein complexes as targets for therapeutic intervention; DeJong ES et al.; Today, the majority of pharmaceuticals developed to treat cancers and viral/bacterial infections target cellular, bacterial or viral proteins known to be associated with a given pathology . Although proteins are the focus of most current drug discovery efforts, exciting new research has recently begun which aims to exploit ribonucleic acid (RNA) and RNP particles as novel targets for pharmaceutical development . These RNA-targeted research efforts have been fueled by an increased appreciation for the central role played by RNA and RNA-protein interactions in many biological processes and diseases, together with a better understanding of RNA structure and an improvement in biophysical/biochemical techniques available to study RNA . As for protein targets, genome sequencing is greatly accelerating the identification of human and microbial RNA transcripts for targeted drug discovery . With this explosion in the number of potential RNA and RNP targets, the effective development of specific small molecule RNA-based drugs requires robust and general approaches for detecting and quantifying RNA-ligand interactions, which can be used as high-throughput screens (HTS) and for obtaining rapid structural information to guide rational drug design . In this review, an overview of the potential for therapeutic intervention based on RNA and RNP targets is presented, together with recent efforts to develop generally useful nuclear magnetic resonance (NMR) and fluorescence binding assays for screening and optimizing drugs aimed at RNA and RNP targets.

Mikrobiol Z, 2002 Jan-Feb, 64(1), 3 - 10
{Specific immunoglobulins as effective drugs for treatment of virus infections: present state and urgent tasks in Ukraine}; Diachenko NS et al.; The thesis about importance of specific immunoglobulin preparations in treatment of infectious diseases of viral and microbial etiology, uncontrollable infections, caused by representatives of herpes viruses family in particular, is developed in the paper . The types of immunoglobulin preparations, their advantages, technology peculiarities has been considered; the experience of application, including that of the authors have been analyzed . The necessity and expedience of intensive development of this branch of immunobiotechnology in Ukraine is proved, especially in connection with a high level of infectious morbidity in this country, concrete recommendations are given.

EMBO Rep, 2002 Apr, 3(4), 378 - 83
The Drosophila homolog of NTF-2, the nuclear transport factor-2, is essential for immune response; Bhattacharya A et al.; Nuclear transport factor-2 (NTF-2) functions in yeast and mammalian cell culture in targeting proteins into the nucleus . The Drosophila homolog, DNTF-2, is an essential component of the nuclear import machinery, since ntf mutants are lethal . Interestingly, hypomorphic alleles show specific phenotypes . Some are viable, but the number of omatidia in the eye is severely reduced . The immune response in the Drosophila larval fat body is also affected; the three NF-kappaB/Rel proteins Dorsal, Dif and Relish do not target to the nucleus after infection, and, consequently, the expression of the anti-microbial peptide genes drosomycin, attacin and drosocin is severely impaired . Hence, in spite of its general requirement in many developmental processes, DNTF-2 has a higher specific requirement in the development of the eye and in the immune response . We also found that DNTF-2 interacts directly with Mbo/DNup88, which does not contain phenylalanine-glycine-rich repeats, but has been shown to function in the import of Rel proteins.

J Control Release, 2002 Apr 23, 80(1-3), 259 - 71
Poly(ethylene glycol) (PEG) conjugated arginine deiminase: effects of PEG formulations on its pharmacological properties; Holtsberg FW et al.; Some tumors, such as melanomas and hepatocellular carcinomas, have a unique nutritional requirement for arginine . Thus, enzymatic degradation of extracellular arginine is one possible means for inhibiting these tumors . Arginine deiminase is an arginine degrading enzyme (ADI) that has been studied as an anti-cancer enzyme . However, ADI has a short serum half-life and, as a microbial enzyme, is highly immunogenic . Formulation of other therapeutic proteins with poly(ethylene glycol) (PEG) has overcome these problems . Here, ADI-PEGs were synthesized using PEGs of varying size, structure (linear or branched chain) and linker chemistries . All ADI-PEGs retained approximately 50% of enzyme activity when PEG was covalently attached to approximately 40% of the primary amines irrespective of the PEG molecular weight or attachment chemistry used . However, it was observed that, as the PEG size increases to 20 kDa, there was a corresponding increase in the pharmacokinetic (pK) and pharmacodynamic (pD) properties of the formulation . Variation in PEG linker or structure, or the use of PEGs >20,000 mw, did not affect the pK or pD . As has been shown with other therapeutic proteins, repeated injection of ADI-PEG into experimental animals resulted in significantly lower titers of antibodies against this protein than unmodified ADI . These data suggest that formulation of ADI with PEG of 20,000 mw results is the optimal method for formulating this promising therapeutic agent.

J Microbiol Methods, 2002 Jun, 50(1), 63 - 73
Evaluation of redox indicators and the use of digital scanners and spectrophotometer for quantification of microbial growth in microplates; Gabrielson J et al.; The growth indicators 2,3,5-triphenyltetrazolium chloride (TTC), 2-{4-iodophenyl}-3-{4-dinitrophenyl}-5-phenyltetrazolium chloride (INT), 2,3-bis{2-methoxy-4-nitro-5-sulfophenyl}-2H-tetrazolium-5-carboxanilide inner salt (XTT), 3-{4,5-dimethylthiazol-2-yl}-2,5-diphenyltetrazolium bromide (MTT), and resazurin were tested for their ability to indicate bacterial growth/growth inhibition . Two reading devices were evaluated and compared, a microplate spectrophotometer and a digital flatbed scanner . The bacteria used in the study were cultivated in 96-wells microplates and readings were made after 24 h . The scanned pictures were analysed with a software developed in-house to generate numerical values . It was found that resazurin was difficult to use since it shifts between three colours . MTT and TTC had a high correlation between the spectrophotometer data and the data from the scanned images . The reproducibility was similar for both reading devices . In no case was there a need to resuspend the pellets before reading . Both the XTT and INT showed lower correlations.It is concluded that bacterial growth/growth inhibition can be easily and reproducibly measured from microplate cultivations with a flatbed scanner or with a microplate spectrophotometer.

J Microbiol Methods, 2002 Jun, 50(1), 39 - 54
Electron energy loss spectroscopy techniques for the study of microbial chromium(VI) reduction; Daulton TL et al.; Electron energy loss spectroscopy (EELS) techniques were used to determine oxidation state, at high spatial resolution, of chromium associated with the metal-reducing bacteria, Shewanella oneidensis, in anaerobic cultures containing Cr(VI)O4(2-) . These techniques were applied to fixed cells examined in thin section by conventional transmission electron microscopy (TEM) as well as unfixed, hydrated bacteria examined by environmental cell (EC)-TEM . Two distinct populations of bacteria were observed by TEM: bacteria exhibiting low image contrast and bacteria exhibiting high contrast in their cell membrane (or boundary) structure which was often encrusted with high-contrast precipitates . Measurements by EELS demonstrated that cell boundaries became saturated with low concentrations of Cr and the precipitates encrusting bacterial cells contained a reduced form of Cr in oxidation state + 3 or lower.

Int J Parasitol, 2002 May, 32(5), 551 - 62
Molecular biology techniques in parasite ecology; Monis PT et al.; Molecular techniques are increasingly being used to study the ecology of a variety of organisms . These techniques represent important tools for the study of the systematics, population genetics, biogeography and ecology of parasites . Here, we review the techniques that have been employed to study the ecology and systematics of parasites (including bacteria and viruses) . Particular emphasis is placed on the techniques of isoenzyme electrophoresis, in situ hybridisation and nucleic acid amplification to characterise parasite/microbial communities . The application of these techniques will be exemplified using ticks, bacterial endosymbionts and parasitic protozoa.

BMC Complement Altern Med . 2002 Apr 10;2(1):4.
Effect of a homeopathic drug, Chelidonium, in amelioration of p-DAB induced hepatocarcinogenesis in mice; Biswas SJ et al.; BACKGROUND: Crude extracts of Chelidonium majus, and also purified compounds derived from crude extracts of this plant, have been reported to exhibit anti-viral, anti-inflammatory, anti-tumor and anti-microbial properties both in vitro and in vivo . Chelidonium is a homeopathic drug routinely used against various liver disorders including cancer in humans . Two potencies of Chelidonium (Ch-30, Ch-200) have been tested for their possible anti-tumor and enzyme modulating activities in liver and anti-clastogenic effects during p-DAB-induced hepatocarcinogenesis in mice compared to suitable controls . METHODS: Several cytogenetic and enzymatic protocols were used at three fixation intervals; at 60 days, 90 days and 120 days of treatment . Different sets of healthy mice were fed: i) hepatocarcinogen, p-DAB plus phenobarbital (PB), ii) only PB, iii) neither p-DAB nor PB (normal control) . One set of mice fed with p-DAB plus PB was also fed Ch-30 (iv) and another set Ch-200 (v) . All standard currently used methods were adopted for cytogenetical preparations and for the enzyme assays . RESULTS: All group (i) mice developed tumors in liver at all fixation intervals, while none of group (ii) and (iii) mice developed any tumors . About 40% mice in group (iv) and group (v) did not show tumor nodules in their liver . Feeding of Chelidonium to group (iv) and (v) mice reduced genotoxic effects to a significant extent (p < 0.05 to p < 0.001) . CONCLUSION: The homeopathic drug Chelidonium exhibited anti-tumor and anti-genotoxic activities and also favorably modulated activities of some marker enzymes . Microdoses of Chelidonium may be effectively used in combating liver cancer.

Lett Appl Microbiol, 2002, 34(4), 279 - 82
Microfloral contamination and hydrolytic enzyme differences between monsooned and non-monsooned coffees; Ahmad R et al.; AIMS: To analyse and compare, for the first time, fungal and bacterial populations and hydrolytic enzyme production in four monsooned and non-monsooned Arabica and Robusta coffee types . METHODS AND RESULTS: Overall, using serial dilution, the populations of bacteria (approximately 10(8) cfu g(-1)) were highest in monsooned coffees of both varieties . Fungal populations were lower (10(5) cfu g(-1)) and found predominantly on monsooned coffee beans . The major fungal species were Aspergillus terreus, A . restrictus and A . ochraceus . Of 19 semi-quantitative enzymes analysed, significantly higher concentrations of 2-naphthyl-butyrate, caprylate and 2-naphthyl-D-galactopyranosidase were present in Arabica monsooned coffee . CONCLUSIONS: The results suggest that speciality monsooned coffee has markedly different microbial and physiological characteristics from normally produced green coffees . SIGNIFICANCE AND IMPACT OF THE STUDY: Monsooned coffee may have a higher contamination with spoilage moulds, especially mycotoxigenic species.

Nat Immunol, 2002 May, 3(5), 435 - 42 Epub 2002 Apr 08.
Lipid length controls antigen entry into endosomal and nonendosomal pathways for CD1b presentation; Moody DB et al.; CD1 proteins present various glycolipid antigens to T cells, but the cellular mechanisms that control which particular glycolipids generate T cell responses are not understood . We show here that T cell recognition of glucose monomycolate antigens with long (C(80)) alkyl chains involves the delivery of CD1b proteins and antigens to late endosomes in a process that takes several hours . In contrast, analogs of the same antigen with shorter (C(32)) alkyl chains are rapidly, but inefficiently, presented by cell surface CD1b proteins . Dendritic cells (DCs) preferentially present long-chain glycolipids, which results, in part, from their rapid internalization and selective delivery of antigens to endosomal compartments . Nonprofessional antigen-presenting cells, however, preferentially present short-chain glycolipids because of their lack of prominent endosomal presentation pathways . Because long alkyl chain length distinguishes certain microbial glycolipids from common mammalian glycolipids, these findings suggest that DCs use a specialized endosomal-loading pathway to promote preferential recognition of glycolipids with a more intrinsically foreign structure.

J Biosci, 2002 Mar, 27(2), 165 - 86
Origins of gene, genetic code, protein and life: comprehensive view of life systems from a GNC-SNS primitive genetic code hypothesis; Ikehara K; We have investigated the origin of genes, the genetic code, proteins and life using six indices (hydropathy, alpha-helix, beta-sheet and beta-turn formabilities, acidic amino acid content and basic amino acid content) necessary for appropriate three-dimensional structure formation of globular proteins . From the analysis of microbial genes, we have concluded that newly-born genes are products of nonstop frames (NSF) on antisense strands of microbial GC-rich genes {GC-NSF(a)} and from SNS repeating sequences {(SNS)n} similar to the GC-NSF(a) (S and N mean G or C and either of four bases, respectively) . We have also proposed that the universal genetic code used by most organisms on the earth presently could be derived from a GNC-SNS primitive genetic code . We have further presented the {GADV}-protein world hypothesis of the origin of life as well as a hypothesis of protein production, suggesting that proteins were originally produced by random peptide formation of amino acids restricted in specific amino acid compositions termed as GNC-, SNS- and GC-NSF(a)-0th order structures of proteins . The {GADV}-protein world hypothesis is primarily derived from the GNC-primitive genetic code hypothesis . It is also expected that basic properties of extant genes and proteins could be revealed by considerations based on the scenario with four stages.

J Immunol, 2002 Apr 15, 168(8), 3910 - 4
Regulation of IL-1 receptor-associated kinases by lipopolysaccharide; Hu J et al.; IL-1R-associated kinase (IRAK) plays a pivotal role in IL-1R/Toll-like receptor (TLR)-mediated signaling and NF-kappaB activation . IRAK from leukocytes undergoes rapid activation and inactivation/degradation following IL-1 or LPS stimulation . The rapid degradation of IRAK may serve as a negative feedback mechanism of down-regulating IL-1R/TLR-mediated signaling and cytokine gene transcription . Although IL-1/IL-1R-triggered IRAK degradation has been studied in detail, the mechanism of LPS-induced IRAK activation and degradation is not clearly defined . In this study, we demonstrate that the IRAK N-terminal 186-aa region is required for LPS-induced degradation . The N-terminally truncated IRAK protein expressed in human monocytic THP-1 cells remains stable upon LPS challenge . In comparison, IRAK as well as the IRAK mutant with C-terminal truncation undergo degradation with LPS stimulation . We demonstrate that pretreatment with protein kinase C inhibitor calphostin inhibits LPS-induced IRAK degradation . Furthermore, we observe coimmunoprecipitation of endogenous IRAK and protein kinase C-zeta protein . We show that functional TLR4 is required for LPS-mediated IRAK degradation . IRAK protein in the murine GG2EE cells harboring a mutated TLR4 gene does not undergo degradation upon LPS treatment . In sharp contrast, we observe that the IRAK homolog, IRAK2, does not undergo degradation upon prolonged LPS treatment, suggesting complex regulation of the innate immunity network upon microbial challenge.

J Immunol, 2002 Apr 15, 168(8), 3697 - 701
Cutting edge: biasing immune responses by directing antigen to macrophage Fc gamma receptors; Anderson CF et al.; An immune response can deviate toward either a Th1- or Th2-like response . In this work we examine the contribution that activated macrophages and IgG Abs make toward this deviation . The use of activated macrophages as APCs resulted in a strong polarized T cell response that was predominated by IFN-gamma . However, when Ag was targeted to FcgammaRs on these macrophages, the T cell response was reversed and biased toward a Th2-like response . This Th2-like phenotype was stable and was retained when the T cells were subsequently restimulated under nonbiasing conditions . The T cell biasing and its reversal via FcgammaR was also observed in vivo . Mice vaccinated with IgG-opsonized OVA made high levels of IgG Ab of the IgG1 isotype . These studies demonstrate that the ligation of FcgammaR on activated macrophages can reverse the Th1 biasing that occurs as a result of innate immune responses to microbial products.

Eur Respir J, 2002 Mar, 19(3), 538 - 45
Interactions between respiratory tract infections and atopy in the aetiology of asthma; Holt PG et al.; The prevalence of asthma, in particular atopic asthma, has markedly increased in recent years . Accumulating evidence suggests that environmental factors associated with allergic sensitization and exposure to microbial stimuli during infancy and early childhood, are associated with these changes in prevalence . However, considerable controversy surrounds the role of microbial agents, as evidence has been presented for both positive and negative effects in this context . The review below focuses upon interactions between immune competence during infancy, the development of T-helper (Th)1-polarized versus Th2-polarized memory against inhalant allergens, and susceptibility to virus infection . In particular, recent finding are highlighted which suggest that delayed postnatal maturation of Th1 function is associated with increased risk for early postnatal sensitization to inhalant allergens, and also with risk for viral bronchiolitis during infancy . Variations in the kinetics of postnatal maturation of T-helper 1 function may in part be attributable to polymorphisms in the CD14 gene, which influence host responsiveness both to bacterial as well as viral stimuli.

Appl Microbiol Biotechnol, 2002 Mar, 58(3), 400 - 8 Epub 2001 Dec 08.
Inhibition of microbial H2S production in an oil reservoir model column by nitrate injection; Myhr S et al.; The effect of nitrate addition on microbial H2S production in a seawater-flooded oil reservoir model column with crude oil as carbon and energy source was investigated . Injection of 0.5 mM nitrate for 2.5-3.5 months led to complete elimination of H2S (initially 0.45-0.67 mM) . The major decline in H2S level coincided with the first complete nitrate consumption and production of nitrite . When nitrate was excluded, H2S production resumed after approximately 2.5 months and reached previous levels after approximately 5 months . Using a fluorescent antibody technique, three populations each of sulfate-reducing bacteria (SRB) and nitrate-reducing bacteria (NRB) were monitored . SRB dominated the anoxic zone prior to nitrate addition, comprising 64-93% of the total bacterial population . The monitored NRB constituted less than 6% and no increase was observed during nitrate addition (indicating that other, unidentified, NRB populations were present) . After 1-3 months without significant H2S production (3.5-5.5 months with nitrate), the SRB population collapsed, the fraction being reduced to 9-25% . The dominant SRB strain in the column, which constituted on average 94% of the monitored SRB population, was partly/completely inhibited by 50/75 microM nitrite in batch culture tests . Similar nitrite concentrations (50-150 microM) were detected in the column when the H2S level declined, indicating that nitrite inhibition was the main cause of H2S elimination . The results from this study indicate that nitrate/nitrite can be used to prevent detrimental SRB activity in oil reservoirs.

Curr Opin Microbiol, 2002 Apr, 5(2), 149 - 53
Mining genome databases to identify and understand new gene regulatory systems; Stormo GD et al.; The availability of a large number of sequenced microbial genomes allows us to conduct systematic studies on microbial gene regulatory systems . Computational methods, using comparative genomics approaches, are powerful tools to understand their mechanisms and evolutionary history . Recent advances in computational methodology for uncovering transcriptional regulatory components and their interactions are discussed.

FEMS Microbiol Lett, 2002 Feb 19, 208(1), 69 - 75
Genetic and restriction analysis of the 16S-23S rDNA internal transcribed spacer regions of the acetic acid bacteria; Trcek J et al.; The 16S-23S rDNA internal transcribed spacer regions of the acetic acid bacteria were sequenced and evaluated for molecular identification of these bacteria . All the sequenced spacers contained genes for tRNA(Ile) and tRNA(Ala), and the antitermination element . The sequences revealed 56.8-78.3% similarity . By PCR amplification of the spacers from 57 strains of acetic acid bacteria, single products of similar sizes were produced . Digestion of the spacers by HaeIII and HpaII restriction enzymes resulted in 12 distinct groups of restriction types . All the restriction profiles obtained after analysis of microbial populations from vinegar matched one of the 12 groups.

Biotechnol Prog, 2002 Mar-Apr, 18(2), 257 - 61
Purification and identification of an Escherichia coli beta-keto ester reductase as 2,5-diketo-D-gluconate reductase YqhE; Habrych M et al.; An NADPH-dependent enzyme that reduces ethyl 2-methylacetoacetate stereoselectively to ethyl (2R)-methyl-(3S)-hydroxybutanoate was purified 730-fold from Escherichia coli . The N-terminal amino acid sequence data obtained from the purified reductase were used to search the E . coli genome, and a single match was found at the start of the yqhE open reading frame . The YqhE protein had been identified previously by Yum et al . as a 2,5-diketo-D-gluconate reductase on the basis of sequence similarity to other bacterial homologues {Yum, D.-Y.; Lee, B.-Y.; Pan, J.-G . Appl.Environ . Microbiol . 1999, 65, 3341-3346}; however, it had not been examined for beta-keto ester reductions . Our results thus link a key enzyme in the microbial production of ascorbate with stereoselective beta-keto ester reductions, two important fields in biocatalysis . The purified YqhE reductase accepts ethyl acetoacetate and a variety of 2-substituted derivatives, and its sequence is similar to other aldose reductase superfamily members that also reduce alpha-substituted beta-keto esters to syn-(2R,3S) alcohols.

Prep Biochem Biotechnol, 2002 Feb, 32(1), 1 - 16
Optimization study of doxorubicin liposomal preparations coated with laminin fragments; Alminana N et al.; Immunoliposomes, coated with two peptide sequences and loaded with doxorubicin, were prepared . The influence of different parameters in the sequential steps of liposomal preparations was studied as, for instance, lipid composition, size reduction methods, elimination of non-entrapped drug, and peptide coating sequence . Results were evaluated, such as entrapment efficiency, phospholipid/drug and phospholipid/peptide relationship, and size of final preparations . Effective size reduction was only achieved through probe sonication and the presence of peptides on the surface of liposomes, which does not modify, significantly, the final phospholipid/drug relationship, related to the initial values; however, they promoted a slight increase in the size of final preparations . Dialysis was the most suitable method to wash liposomes from reactants, drug and peptides, as well as being the cleanest process to avoid microbial contamination without significant dilution . Peptide coating yields were similar for liposomal compositions presenting free carboxyl groups on the surface . As determined by other authors, the presence of polyethylene glycol monomethoxy chains on the surface reduces the reactivity of NPGE carboxylic groups.

Int J Food Microbiol, 2002 Mar, 73(2-3), 409 - 14
Debating the biological reality of modelling preservation; ter SP et al.; Predictive food microbiology is a rapidly developing science and has made great advances . The aim is to debate a number of issues in modelling preservation: (1) inoculum and prehistory effects on lag times and process susceptibility; (2) mechanistic vs . empirical modelling; and (3) concluding remarks (the Species concept, methodology and biovariability) . Increasing the awareness in these issues may bridge the gap between the complex reality in food microbial physiology and the application potential of predictive models . The challenge of bringing integrated preservation or risk analysis further and developing ways to truly model and link biological susceptibility distributions from raw ingredients via process survival to outgrowth probabilities in the final product remains.

Int J Food Microbiol, 2002 Mar, 73(2-3), 187 - 96
Using survival analysis to investigate the effect of UV-C and heat treatment on storage rot of strawberry and sweet cherry; Marquenie D et al.; Ultraviolet light and heat treatment are proposed as alternative techniques for the use of chemicals to reduce the development of the spoilage fungi Botrytis cinerea and Monilinia fructigena on strawberry and sweet cherry, respectively, during storage . In order to investigate the effect of both physical techniques on microbial inactivation and on fruit quality, inoculated berries were subjected to different temperatures (40-48 degrees C) and UV-C doses (0.05-1.50 J/cm2) . For each condition, 20 berries were used . After the treatment, fungal growth, visual damage (holes, stains) and fruit firmness were evaluated during a period of 10 days . The experimental data were analysed statistically using survival analysis techniques . Fungal growth on strawberries was significantly retarded using UV-C doses of 0.05 J/cm2 and higher . The same treatment had no significant effect when applied to cherries . The highest doses (1.00 and 1.50 J/cm2) had a negative effect on the calyx of the strawberry, causing browning and drying of the leaves . No beneficial effect of a low temperature treatment (40-48 degrees C) on the shelf life of strawberries was observed, but fungal development on cherries was retarded at temperatures of 45 and 48 degrees C . These temperatures caused severe damage on strawberries (soft stains, holes, decreased firmness), but had no influence on the quality of sweet cherries.

Eur J Immunol, 2002 Apr, 32(4), 1147 - 56
Transgenic B lymphocytes expressing a human cold agglutinin escape tolerance following experimental infection of mice by Mycoplasma pulmonis; Havouis S et al.; Several microbial infections, including Mycoplasma pneumoniae respiratory infection, are capable, in man, of transiently inducing the expression of anti-red blood cell autoantibody called cold agglutinins (CA) . To analyze the mechanisms by which immune tolerance is broken following a mycoplasma infection, we used transgenic mice expressing a pathogenic human CA, designated CA-GAS, specific for sialylated carbohydrates . In these mice peripheral deletion of autoreactive B lymphocytes and receptor editing, prevent the development of autoimmune hemolytic anemia . Experimental infections of transgenic mice with Mycoplasma pulmonis resulted in a high anti-mycoplasma antibody response (despite a severe B cell depletion at the onset of infection), and an important induction of serum CA concentrations, reaching in some mice pathological titers . Whereas in naive mice, only a small percentage of CA-expressing cells could be detected, in infected mice, a majority of circulating B lymphocytes were large B220(-) cells, which expressed the transgenic immunoglobulin . Immunization of the transgenic mice with keyhole limpet hemocyanin and Freund's adjuvant, to nonspecifically stimulate the expression of the passenger transgenes, only moderately increased the CA titers . These results indicate that M . pulmonis infection is capable of breaking immune tolerance in the CA-transgenic mice, in part through specific activation of CA-expressing B lymphocytes . This experimental infection mimics the induction of CA in humans and provide an animal model for studying the genesis of the autoimmune hemolytic anemia.

Heredity, 2002 Feb, 88(2), 85 - 93
The gifts that keep on giving: physiological functions and evolutionary dynamics of male seminal proteins in Drosophila; Wolfner MF; During mating, males transfer seminal proteins and peptides, along with sperm, to their mates . In Drosophila melanogaster, seminal proteins made in the male's accessory gland stimulate females' egg production and ovulation, reduce their receptivity to mating, mediate sperm storage, cause part of the survival cost of mating to females, and may protect reproductive tracts or gametes from microbial attack . The physiological functions of these proteins indicate that males provide their mates with molecules that initiate important reproductive responses in females . A new comprehensive EST screen, in conjunction with earlier screens, has identified approximately 90% of the predicted secreted accessory gland proteins (Acps) . Most Acps are novel proteins and many appear to be secreted peptides or prohormones . Acps also include modification enzymes such as proteases and their inhibitors, and lipases . An apparent prohormonal Acp, ovulin (Acp26Aa) stimulates ovulation in mated Drosophila females . Another male-derived protein, the large glycoprotein Acp36DE, is needed for sperm storage in the mated female and through this action can also affect sperm precedence, indirectly . A third seminal protein, the protease inhibitor Acp62F, is a candidate for contributing to the survival cost of mating, given its toxicity in ectopic expression assays . That male-derived molecules manipulate females in these ways can result in a molecular conflict between the sexes that can drive the rapid evolution of Acps . Supporting this hypothesis, an unusually high fraction of Acps show signs consistent with their being targets of positive Darwinian selection.

Nature, 2002 Apr 4, 416(6880), 522 - 4
Abiogenic formation of alkanes in the Earth's crust as a minor source for global hydrocarbon reservoirs; Sherwood Lollar B et al.; Natural hydrocarbons are largely formed by the thermal decomposition of organic matter (thermogenesis) or by microbial processes (bacteriogenesis) . But the discovery of methane at an East Pacific Rise hydrothermal vent and in other crustal fluids supports the occurrence of an abiogenic source of hydrocarbons . These abiogenic hydrocarbons are generally formed by the reduction of carbon dioxide, a process which is thought to occur during magma cooling and-more commonly-in hydrothermal systems during water-rock interactions, for example involving Fischer-Tropsch reactions and the serpentinization of ultramafic rocks . Suggestions that abiogenic hydrocarbons make a significant contribution to economic hydrocarbon reservoirs have been difficult to resolve, in part owing to uncertainty in the carbon isotopic signatures for abiogenic versus thermogenic hydrocarbons . Here, using carbon and hydrogen isotope analyses of abiogenic methane and higher hydrocarbons in crystalline rocks of the Canadian shield, we show a clear distinction between abiogenic and thermogenic hydrocarbons . The progressive isotopic trends for the series of C1-C4 alkanes indicate that hydrocarbon formation occurs by way of polymerization of methane precursors . Given that these trends are not observed in the isotopic signatures of economic gas reservoirs, we can now rule out the presence of a globally significant abiogenic source of hydrocarbons.

J Virol, 2002 May, 76(9), 4251 - 9
Immunodominance in virus-induced CD8(+) T-cell responses is dramatically modified by DNA immunization and is regulated by gamma interferon; Rodriguez F et al.; The phenomenon whereby the host immune system responds to only a few of the many possible epitopes in a foreign protein is termed immunodominance . Immunodominance occurs not only during microbial infection but also following vaccination, and clarification of the underlying mechanism may permit the rational design of vaccines which can circumvent immunodominance, thereby inducing responses to all epitopes, dominant and subdominant . Here, we show that immunodominance affects DNA vaccines and that the effects can be avoided by the simple expedient of epitope separation . DNA vaccines encoding isolated dominant and subdominant epitopes induce equivalent responses, confirming a previous demonstration that coexpression of dominant and subdominant epitopes on the same antigen-presenting cell (APC) is central to immunodominance . We conclude that multiepitope DNA vaccines should comprise a cocktail of plasmids, each with its own epitope, to allow maximal epitope dispersal among APCs . In addition, we demonstrate that subdominant responses are actively suppressed by dominant CD8(+) T-cell responses and that gamma interferon (IFN-gamma) is required for this suppression . Furthermore, priming of CD8(+) T cells to a single dominant epitope results in strong suppression of responses to other normally dominant epitopes in immunocompetent mice, in effect rendering these epitopes subdominant; however, responses to these epitopes are increased 6- to 20-fold in mice lacking IFN-gamma . We suggest that, in agreement with our previous observations, IFN-gamma secretion by CD8(+) T cells is highly localized, and we propose that its immunosuppressive effect is focused on the APC with which the dominant CD8(+) T cell is in contact.

Trends Genet, 2002 Apr, 18(4), 176 - 9
Identifying functional links between genes using conserved chromosomal proximity; Yanai I et al.; Conservation of proximity of a pair of genes across multiple genomes generally indicates that their functions could be linked . Here, we present a systematic evaluation using 42 complete microbial genomes from 25 phylogenetic groups to test the reliability of this observation in predicting function for genes . We find a relationship between the number of phylogenetic groups in which a gene pair is proximate and the probability that the pair belongs to a common pathway . Our method produces 1586 links between ortholog families substantiated by observed proximity in genomes representing at least three phylogenetic groups . Of the pairs annotated in the KEGG database, 80% are in the same biological pathway in KEGG.

Int J Food Microbiol, 2002 Mar 25, 74(1-2), 139 - 59
On the use of the Weibull model to describe thermal inactivation of microbial vegetative cells; van Boekel MA; This paper evaluates the applicability of the Weibull model to describe thermal inactivation of microbial vegetative cells as an alternative for the classical Bigelow model of first-order kinetics; spores are excluded in this article because of the complications arising due to the activation of dormant spores . The Weibull model takes biological variation, with respect to thermal inactivation, into account and is basically a statistical model of distribution of inactivation times . The model used has two parameters, the scale parameter alpha (time) and the dimensionless shape parameter beta . The model conveniently accounts for the frequently observed nonlinearity of semilogarithmic survivor curves, and the classical first-order approach is a special case of the Weibull model . The shape parameter accounts for upward concavity of a survival curve (beta < 1), a linear survival curve (beta = 1), and downward concavity (beta > 1) . Although the Weibull model is of an empirical nature, a link can be made with physiological effects . Beta < 1 indicates that the remaining cells have the ability to adapt to the applied stress, whereas beta > 1 indicates that the remaining cells become increasingly damaged . Fifty-five case studies taken from the literature were analyzed to study the temperature dependence of the two parameters . The logarithm of the scale parameter alpha depended linearly on temperature, analogous to the classical D value . However, the temperature dependence of the shape parameter beta was not so clear . In only seven cases, the shape parameter seemed to depend on temperature, in a linear way . In all other cases, no statistically significant (linear) relation with temperature could be found . In 39 cases, the shape parameter beta was larger than 1, and in 14 cases, smaller than 1 . Only in two cases was the shape parameter beta = 1 over the temperature range studied, indicating that the classical first-order kinetics approach is the exception rather than the rule . The conclusion is that the Weibull model can be used to model nonlinear survival curves, and may be helpful to pinpoint relevant physiological effects caused by heating . Most importantly, process calculations show that large discrepancies can be found between the classical first-order approach and the Weibull model . This case study suggests that the Weibull model performs much better than the classical inactivation model and can be of much value in modelling thermal inactivation more realistically, and therefore, in improving food safety and quality.

Aliment Pharmacol Ther, 2002 Apr, 16(4), 663 - 74
Review article: the concept of entero-colonic encephalopathy, autism and opioid receptor ligands; Wakefield AJ et al.; There is growing awareness that primary gastrointestinal pathology may play an important role in the inception and clinical expression of some childhood developmental disorders, including autism . In addition to frequent gastrointestinal symptoms, children with autism often manifest complex biochemical and immunological abnormalities . The gut-brain axis is central to certain encephalopathies of extra-cranial origin, hepatic encephalopathy being the best characterized . Commonalities in the clinical characteristics of hepatic encephalopathy and a form of autism associated with developmental regression in an apparently previously normal child, accompanied by immune-mediated gastrointestinal pathology, have led to the proposal that there may be analogous mechanisms of toxic encephalopathy in patients with liver failure and some children with autism . Aberrations in opioid biochemistry are common to these two conditions, and there is evidence that opioid peptides may mediate certain aspects of the respective syndromes . The generation of plausible and testable hypotheses in this area may help to identify new treatment options in encephalopathies of extra-cranial origin . Therapeutic targets for this autistic phenotype may include: modification of diet and entero-colonic microbial milieu in order to reduce toxin substrates, improve nutritional status and modify mucosal immunity; anti-inflammatory/immunomodulatory therapy; and specific treatment of dysmotility, focusing, for example, on the pharmacology of local opioid activity in the gut.

Dig Liver Dis, 2002 Jan, 34(1), 29 - 38
Treatment of severe Crohn's disease using antimycobacterial triple therapy--approaching a cure?
Borody TJ, Leis S, Warren EF, Surace R.
BACKGROUND: Mycobacterium avium subspecies paratuberculosis is probably the best candidate for a microbial cause of Crohn's disease although arguments to the contrary can be equally convincing . Growing evidence suggests that prolonged antimycobacterial combination therapy can improve Crohn's disease in some patients . AIM: To report long-term observations in patients with severe Crohn's disease treated with triple macrolide-based antimycobacterial therapy . PATIENTS: A series of 12 patients (7 male, 5 female; aged 15-42 years) with severe, obstructive or penetrating Crohn's disease were recruited . METHODS: Patients failing maximal therapy were commenced prospectively on a combination of rifabutin (450 mg/d), clarithromycin (750 mg/d) and clofazimine (2 mg/kg/d) . Progress was monitored through colonoscopy, histology, clinical response and Harvey-Bradshaw activity index . RESULTS: Follow-up data were available for up to 54 months of therapy Six out of 12 patients experienced a full response to the antiMycobacterium avium subspecies paratuberculosis combination achieving complete clinical, colonoscopic and histologic remission of Crohn's disease . Four of these patients were able to cease treatment after 24-46 months, 3 of whom remained in total remission without treatment for up to 26 months and one patient relapsed after six months off treatment . A partial response to the anti-Mycobacterium avium subspecies paratuberculosis combination was seen in 2 patients showing complete clinical remission with mild histologic inflammation . Return to normal of terminal ileal strictures occurred in 5 patients . Harvey-Bradshaw activity index in patients showing a full or partial response to therapy fell from an initial 13.4 +/- 1 . 91 to 0 . 5 +/- 0 . 47 {n = 8, p < 0 . 001) after 52-54 months . CONCLUSIONS: Reversal of severe Crohn's disease has been achieved in 6/12 patients using prolonged combination anti-Mycobacterium avium subspecies paratuberculosis therapy alone . Three patients remain in long-term remission with no detectable Crohn's disease off all therapy These results support a causal role for Mycobacterium avium subspecies paratuberculosis in Crohn's disease while also suggesting that a cure may become possible.

Curr Opin Drug Discov Devel, 2002 Mar, 5(2), 304 - 16
Mother nature's combinatorial libraries; their influence on the synthesis of drugs; Kingston DG et al.; Natural products or secondary metabolites, whether from the microbial, plant or marine worlds, represent the results of evolutionary pressures to preserve and enhance the life of their producing organism . They have evolved into structurally and usually stereochemically complex compounds with specific bioactivities . They thus represent a diverse 'combinatorial library' that may have potential pharmaceutical use . In principle, the combination of this diverse library with the methods of combinatorial chemistry could lead to an unlimited supply of diverse and complex structures, and is recommended as a fruitful approach for future drug development . Examples of the application of combinatorial methods to nature's combinatorial library will be presented and discussed, with an emphasis on the antitumor, anti-infective and pain control disease areas.

J Investig Dermatol Symp Proc, 2001 Dec, 6(3), 167 - 9
Microbial ecology of human skin in health and disease; Fredricks DN; Cultivation of human skin reveals numerous bacteria and at least one fungus to be normal inhabitants of this ecosystem; however, most of our knowledge about the microbiology of human skin was acquired decades ago . Modern techniques employing nucleic acid-based microbial identification methods demonstrate the limitations of cultivation for appreciating microbial diversity in many ecosystems . The application of modern molecular methods to the study of skin may offer new perspectives on the resident microfora, and new insights into the causes of antibiotic responsive dermatologic conditions, such as acne and rosacea.

Comp Med, 2001 Apr, 51(2), 163 - 70
Intestinal cannulation: model for study of the midgut of the pig; Jacobson M et al.; PURPOSE: To develop a pig model that would enable repeated biopsy specimen collection and endoscopic monitoring of the gut . This would increase precision of the experiment and reduce the number of experimental animals required . METHODS: Six 10-week-old Yorkshire pigs underwent surgery, and a cannula was inserted in the cecum . Two pigs served as non-operated controls . The health status of the animals was monitored by clinical, hematologic, and biochemical examinations and by studies of gut motility and microbial flora . The experimental period lasted for eight weeks and approximately 45 biopsy specimens were obtained from each animal . RESULTS: Repeated endoscopy was performed and biopsy specimens were taken . Adverse effects on the animal's health were not apparent, and differences were not evident in transit time of digesta or in diversity of the gut microbial flora . After surgery there was a transient increase in the concentrations of haptoglobin, serum amyloid A, and plasma cortisol, and in body temperature and white blood cell count . CONCLUSIONS: It is possible to use an intestinal cannula in the cecum both for endoscopy and biopsy specimen collection . The procedures did not influence health status of the pigs, nor alter gut function . The method will be useful in experimental infection studies as well as in other physiologic investigations.

Lab Anim (NY), 2001 Nov, 30(10), 44 - 52
Damage control: a guide to dealing with an infectious break; Weisbroth SH et al.; A change in the microbial status of laboratory animals can represent a disruptive event in the research process . The author suggests a sequence of events from the time a facility learns of a potential infectious "break," through investigation of its source, and its ultimate control.

J Neurosci, 2002 Apr 1, 22(7), 2478 - 86
The toll-like receptor TLR4 is necessary for lipopolysaccharide-induced oligodendrocyte injury in the CNS; Lehnardt S et al.; The immediate or innate immune response is the first line of defense against diverse microbial pathogens and requires the expression of recently discovered toll-like receptors (TLRs) . TLR4 serves as a specific receptor for lipopolysaccharide (LPS) and is localized on the surface of a subset of mammalian cells . Although innate immunity is a necessary host defense against microbial pathogens, the consequences of its activation in the CNS can be deleterious, as we show here in a developing neural model . We examined the major non-neuronal cell types in the CNS for expression of TLR4 and found that microglia expressed high levels, whereas astrocytes and oligodendrocytes expressed none . Consistent with TLR4 expression solely in microglia, we show that microglia are the only CNS glial cells that bind fluorescently tagged lipopolysaccharide . Lipopolysaccharide led to extensive oligodendrocyte death in culture only under conditions in which microglia were present . To determine whether TLR4 is necessary for lipopolysaccharide-induced oligodendrocyte death in mixed glial cultures, we studied cultures generated from mice bearing a loss-of-function mutation in the tlr4 gene . Lipopolysaccharide failed to induce oligodendrocyte death in such cultures, in contrast to the death induced in cultures from wild-type mice . Finally, stereotactic intracerebral injection of lipopolysaccharide into the developing pericallosal white matter of immature rodents resulted in loss of oligodendrocytes and hypomyelination and periventricular cysts . Our data provide a general mechanistic link between (1) lipopolysaccharide and similar microbial molecular motifs and (2) injury to oligodendrocytes and myelin as occurs in periventricular leukomalacia and multiple sclerosis.

Trends Immunol, 2002 Apr, 23(4), 169 - 71
IL-2 mediates adjuvant effect of dendritic cells; Granucci F et al.; Research into the biology of dendritic cells (DCs) has shown that they play a central role in priming early and late immune responses . The recent finding that DCs produce interleukin-2 (IL-2) after microbial challenge suggests that this could be the mechanism by which DCs link innate and adaptive immunity . This hypothesis is supported also by the observation that murine cytomegalovirus, which is able to establish a persistent infection, can interfere with the ability of infected DCs to produce IL-2 and prime T cells.

J Mass Spectrom, 2002 Mar, 37(3), 283 - 91
Rapid screening and identification of cytochalasins by electrospray tandem mass spectrometry; Prasain JK et al.; The cytochalasin class of fungal metabolites was analyzed by electrospray ionization tandem mass spectrometry (ESI-MS/MS) with the aim of developing a methodology for their rapid identification in microbial extracts . ESI-MS analyses of reference cytochalasins were performed and several product ions were produced in MS/MS experiments on parent ions that are structurally characteristic . A precursor ion search was performed to detect cytochalasins in an ethyl acetate extract of fungal strain RK97-F21 . Three cytochalasins were detected and one of the components was identified as epoxycytochalasin H by comparing the tandem mass spectra of the product ions with those of reference compounds . This finding was further validated by LC/MS and LC/MS/MS experiments .

J Comp Physiol {B}, 2002 Apr, 172(3), 197 - 207 Epub 2002 Jan 23.
Seasonal changes in morphology and function of the gastrointestinal tract of free-living alpine marmots ( Marmota marmota); Hume D et al.; The gastrointestinal tracts of 76 free-living alpine marmots ( Marmota marmota) shot during a population control program in Switzerland were collected and analysed for patterns of change in morphology and function over the period from emergence from hibernation in April to just before re-entry into hibernation in September . Between first emergence and mid-summer (July) the fresh tissue mass of the stomach increased by 105%, the small intestine by 259% (among the largest recorded for a mammal), caecum by 185%, proximal colon by 138%, and distal colon by 144% . Mitotic activity was greatest in the small intestine; the mitotic index was high (40%) compared with indexes in the stomach and hindgut (approximately 4%) even at emergence, and increased to approximately 60% by mid-summer . Microbial activity in the caecum was also significant at emergence . The stomach (length) and caecum (length and fresh mass) increased in response to ingested food earlier than did the small intestine . Between mid-summer and September there were decreases in small intestinal tissue mass and mitotic activity . It is concluded that the gastrointestinal tract of alpine marmots probably continues to function throughout hibernation at a low level, with a mid-winter trough as part of an endogenous circannual rhythm . However, after emergence in spring, increases in size and activity of the tract appear to be a response to ingested food rather than to an endogenous signal . The early signs of down-regulation of the small intestine before re-entry into hibernation, together with its delayed up-regulation in response to food in spring, are consistent with the high costs of maintaining this section of the digestive system.

Surv Ophthalmol, 2002 Mar-Apr, 47(2), 174 - 82
Collagen corneal shields; Willoughby CE et al.; Collagen corneal shields were developed as a corneal bandage lens and are currently indicated for ocular surface protection following surgery and in traumatic and nontraumatic corneal conditions . Collagen shields are manufactured from porcine or bovine collagen and three different collagen shields are currently available with dissolution times of 12, 24, and 72 hours . The theoretical, experimental, and clinical evidence supports a role for collagen corneal shields as a drug delivery device and in the promotion of epithelial and stromal healing . Presoaking the collagen shield in a pharmacological agent with adjunctive topical treatment represents the most efficacious method of utilizing collagen shields for drug delivery . In microbial keratitis collagen shields can enhance drug delivery, promote epithelial and stromal healing, neutralize collagenases, and reduce corneal inflammation . This review will examine the evidence that supports the role of collagen shields in drug delivery and corneal wound healing . Despite a large volume of experimental (animal) work, studies on human subjects, particularly randomized controlled trials, are lacking . The authors are advocating the reassessment of the application and benefits of corneal collagen shields to clinical practice.

Cornea, 2002 Apr, 21(3), 318 - 24
Case reports of three atypical infiltrative keratitis events with high DK soft contact lens wear; Skotnitsky C et al.; PURPOSE: We report three atypical infiltrative keratitis events in patients that had successfully worn highly oxygen permeable (Dk) soft contact lenses on an extended wear (EW) schedule for at least 15 months . These cases highlight the role of patient/practitioner education, patient compliance, examination, and appropriate referrals that are required to reduce the risk of complications during lens wear . METHODS AND RESULTS: Each patient had been wearing high Dk soft lenses on an EW schedule with monthly replacement for at least 15 months and presented with severe pain, redness, and photophobia . The events were characterized by focal infiltrate(s) with an overlying epithelial defect in the superior periphery to mid-periphery of the cornea and extensive diffuse infiltration . CONCLUSIONS: The signs and symptoms of each case were more severe than is typically associated with contact lens-related infiltrative keratitis . Because of the slow progression of signs and relatively fast resolution, the cases were not found to be microbial keratitis . Although high Dk soft contact lenses overcome hypoxia-associated complications associated with extended wear, patients and practitioners must be vigilant as adverse events can still occur and in rare instances can be severe . Education and patient compliance are a crucial part of successful management of patients on EW schedules . Constant reinforcement is necessary to ensure patient compliance.

Nucleic Acids Res . 2002 Apr 1;30(7):e31.
Multiplex Pyrosequencing; Pourmand N et al.; We describe here the development of a new and simple single-tube multiplex Pyrosequencing assay . Genomic DNA or cDNA was employed to PCR amplify region(s) using biotinylated and normal primer(s) . Subsequent to capture of PCR products on streptavidin-coated beads, single-stranded DNA separation and hybridization of multiple sequencing primers, Pyrosequencing was performed . The obtained pyrogram resulted in a unique pattern in which the intensity of the signal determined the number of incorporated nucleotide(s) . Here, we demonstrate the use of this multiplex Pyrosequencing for single nucleotide polymorphisms genotyping and microbial typing.

Appl Environ Microbiol, 2002 Apr, 68(4), 1994 - 2007
Microbial diversity of hydrothermal sediments in the Guaymas Basin: evidence for anaerobic methanotrophic communities; Teske A et al.; Microbial communities in hydrothermally active sediments of the Guaymas Basin (Gulf of California, Mexico) were studied by using 16S rRNA sequencing and carbon isotopic analysis of archaeal and bacterial lipids . The Guaymas sediments harbored uncultured euryarchaeota of two distinct phylogenetic lineages within the anaerobic methane oxidation 1 (ANME-1) group, ANME-1a and ANME-1b, and of the ANME-2c lineage within the Methanosarcinales, both previously assigned to the methanotrophic archaea . The archaeal lipids in the Guaymas Basin sediments included archaeol, diagnostic for nonthermophilic euryarchaeota, and sn-2-hydroxyarchaeol, with the latter compound being particularly abundant in cultured members of the Methanosarcinales . The concentrations of these compounds were among the highest observed so far in studies of methane seep environments . The delta-(13)C values of these lipids (delta-(13)C = -89 to -58 per thousand) indicate an origin from anaerobic methanotrophic archaea . This molecular-isotopic signature was found not only in samples that yielded predominantly ANME-2 clones but also in samples that yielded exclusively ANME-1 clones . ANME-1 archaea therefore remain strong candidates for mediation of the anaerobic oxidation of methane . Based on 16S rRNA data, the Guaymas sediments harbor phylogenetically diverse bacterial populations, which show considerable overlap with bacterial populations of geothermal habitats and natural or anthropogenic hydrocarbon-rich sites . Consistent with earlier observations, our combined evidence from bacterial phylogeny and molecular-isotopic data indicates an important role of some novel deeply branching bacteria in anaerobic methanotrophy . Anaerobic methane oxidation likely represents a significant and widely occurring process in the trophic ecology of methane-rich hydrothermal vents . This study stresses a high diversity among communities capable of anaerobic oxidation of methane.

Appl Environ Microbiol, 2002 Apr, 68(4), 1576 - 84
Phylogenetic diversity of marine cyanophage isolates and natural virus communities as revealed by sequences of viral capsid assembly protein gene g20; Zhong Y et al.; In order to characterize the genetic diversity and phylogenetic affiliations of marine cyanophage isolates and natural cyanophage assemblages, oligonucleotide primers CPS1 and CPS8 were designed to specifically amplify ca . 592-bp fragments of the gene for viral capsid assembly protein g20 . Phylogenetic analysis of isolated cyanophages revealed that the marine cyanophages were highly diverse yet more closely related to each other than to enteric coliphage T4 . Genetically related marine cyanophage isolates were widely distributed without significant geographic segregation (i.e., no correlation between genetic variation and geographic distance) . Cloning and sequencing analysis of six natural virus concentrates from estuarine and oligotrophic offshore environments revealed nine phylogenetic groups in a total of 114 different g20 homologs, with up to six clusters and 29 genotypes encountered in a single sample . The composition and structure of natural cyanophage communities in the estuary and open-ocean samples were different from each other, with unique phylogenetic clusters found for each environment . Changes in clonal diversity were also observed from the surface waters to the deep chlorophyll maximum layer in the open ocean . Only three clusters contained known cyanophage isolates, while the identities of the other six clusters remain unknown . Whether or not these unidentified groups are composed of bacteriophages that infect different Synechococcus groups or other closely related cyanobacteria remains to be determined . The high genetic diversity of marine cyanophage assemblages revealed by the g20 sequences suggests that marine viruses can potentially play important roles in regulating microbial genetic diversity.

Appl Environ Microbiol, 2002 Apr, 68(4), 1516 - 23
Activity and diversity of sulfate-reducing bacteria in a petroleum hydrocarbon-contaminated aquifer; Kleikemper J et al.; Microbial sulfate reduction is an important metabolic activity in petroleum hydrocarbon (PHC)-contaminated aquifers . We quantified carbon source-enhanced microbial SO(4)(2-) reduction in a PHC-contaminated aquifer by using single-well push-pull tests and related the consumption of sulfate and added carbon sources to the presence of certain genera of sulfate-reducing bacteria (SRB) . We also used molecular methods to assess suspended SRB diversity . In four consecutive tests, we injected anoxic test solutions (1,000 liters) containing bromide as a conservative tracer, sulfate, and either propionate, butyrate, lactate, or acetate as reactants into an existing monitoring well . After an initial incubation period, 1,000 liters of test solution-groundwater mixture was extracted from the same well . Average total test duration was 71 h . We measured concentrations of bromide, sulfate, and carbon sources in native groundwater as well as in injection and extraction phase samples and characterized the SRB population by using fluorescence in situ hybridization (FISH) and denaturing gradient gel electrophoresis (DGGE) . Enhanced sulfate reduction concomitant with carbon source degradation was observed in all tests . Computed first-order rate coefficients ranged from 0.19 to 0.32 day(-1) for sulfate reduction and from 0.13 to 0.60 day(-1) for carbon source degradation . Sulfur isotope fractionation in unconsumed sulfate indicated that sulfate reduction was microbially mediated . Enhancement of sulfate reduction due to carbon source additions in all tests and variability of rate coefficients suggested the presence of specific SRB genera and a high diversity of SRB . We confirmed this by using FISH and DGGE . A large fraction of suspended bacteria hybridized with SRB-targeting probes SRB385 plus SRB385-Db (11 to 24% of total cells) . FISH results showed that the activity of these bacteria was enhanced by addition of sulfate and carbon sources during push-pull tests . However, DGGE profiles indicated that the bacterial community structure of the dominant species did not change during the tests . Thus, the combination of push-pull tests with molecular methods provided valuable insights into microbial processes, activities, and diversity in the sulfate-reducing zone of a PHC-contaminated aquifer.

BMC Infect Dis . 2002 Mar 27;2(1):4.
Preventing infection from reusable medical equipment: a systematic review; Sopwith W et al.; BACKGROUND: In 2000, the World Health Organization (WHO) had eight sets of conflicting recommendations for decontaminating medical equipment . We conducted a systematic review of observational studies to assist WHO in reconciling the various guidelines . This paper summarises the methods developed and illustrates the results for three procedures--alcohol, bleach and povidone iodine . METHODS: We developed a Medline search strategy and applied inclusion criteria specifying the decontamination procedures of interest and an outcome of microbial destruction for a set of marker organisms . We developed protocols to assess the quality of studies and categorised them according to the reliability of the methods used . Through an iterative process we identified best practice for the decontamination methods and key additional factors required to ensure their effectiveness . We identified 88 published papers for inclusion, describing 135 separate studies of decontamination . RESULTS: For disinfection with alcohol, best practice was identified from 23 studies as an exposure to 70-80% ethanol or isopropanol for at least 5 minutes . Bleach was effective for sterilization at a concentration of 5000 ppm for 5 minutes and for disinfection at 1000 ppm for 10 minutes (33 studies) . Povidone iodine was only partially effective for disinfection at a concentration of 1% for 15 minutes (15 studies) . CONCLUSIONS: Our findings provide an evidence base for WHO guidelines on decontaminating medical equipment . The results support the recommended use of bleach and show that alcohol could be used more widely than current guidelines suggest, provided best practice is followed . The effectiveness of povidone iodine is uncertain.

Infect Dis Obstet Gynecol, 2001, 9(4), 209 - 14
Performance characteristics of putative tests for subclinical chorioamnionitis; Edwards RK et al.; OBJECTIVE: To evaluate amniotic fluid glucose, matrix metalloproteinase (MMP)-9, interleukin (IL)-6, and IL-12 for diagnosing subclinical chorioamnionitis in women with preterm labor . METHODS: Forty-four women in preterm labor at 22-35 weeks gestation with suspected subclinical chorioamnionitis underwent amniocentesis . Amniotic fluid analysis included Gram stain, culture, and determination of glucose, MMP-9, IL-6, and IL-12 concentrations . Median values of these analytes were compared using the Mann-Whitney U test . Sensitivity, specificity, and positive and negative predictive values were calculated for tests using a positive amniotic fluid culture or delivery within 24 hours as the key outcome variables . RESULTS: Amniotic fluid concentrations of glucose, MMP-9, and IL-6 correlated closely with positive culture or delivery within 24 hours . IL- 12 concentrations did not correlate with either a positive culture or delivery within 24 hours . CONCLUSIONS: Amniotic fluid glucose, MMP-9, and IL-6 reliably predict microbial invasion of the amniotic cavity or imminent delivery . IL- 12 values did not correlate with amniotic fluid culture results or imminent delivery.

Eye, 2002 Jan, 16(1), 27 - 32
Non-trachomatous corneal opacities in the Gambia--aetiology and visual burden; Bowman RJ et al.; AIMS: National blindness surveys conducted in the Gambia in 1986 and 1996 showed an increase in blindness and visual impairment from non-trachomatous opacity . This study aimed to investigate the aetiology of these opacities and to assess the resulting visual burden . METHODS: A population-based, randomised blindness survey was conducted in the Gambia in 1996 . Patients with visual impairment or blindness were examined by an ophthalmologist with a slit lamp . Causes of corneal opacity were determined as accurately as possible by clinical history and examination . RESULTS: A total of 154 patients with non trachomatous corneal opacity were examined of whom 39 had bilateral opacities and 115, unilateral . Causes included corneal infection, measles/vitamin A deficiency, harmful traditional practices and trauma (unilateral scarring) . Overall, corneal pathology alone was responsible for bilateral visual impairment or blindness in 19 (12%) patients and unilateral visual impairment or blindness in 88 (57%) patients . Those patients with bilateral visual impairment or blindness (mean age 59, SD) were older (P= 0.003) than others (mean age 44, SD = 20) . The use of harmful traditional eye practices was associated with bilateral corneal blindness or visual impairment (RR = 2.63, 95% CI 1.11-6.21, P = 0.04) . Although none of the corneal scars reported here were attributed to trachoma, in patients over the age of 45, the prevalence of trachomatous conjunctival scarring in this group was 38.8% compared to 19.4% of the whole nationwide sample . DISCUSSION: Strategies for the prevention (including the quest for cheaper anti-microbial drugs and co-operation with traditional healers) and surgical treatment of these corneal opacities are discussed.

Life Sci Space Res, 1975, 13, 135 - 41
Physical dosimetric evaluations in the Apollo 16 microbial response experiment; Taylor GR et al.; Nine biological species, including viruses, bacteria, fungi, and nematodes, were exposed to various combinations of space vacuum, galactic radiation, and solar UV light during the Apollo 16 space flight . No major changes in number of surviving cells occurred, permitting detailed genetic and somatic studies of returned test subjects . To enable dose-response studies, solar UV was employed as a mutagenic source with cells exposed to full sunlight or to components of the UV spectrum at peak wavelengths of 254, 280, and 300 nanometers over a range of energy levels . Proper in-flight UV irradiation monitoring required the development of a potassium ferrioxalate actinometer and an anaerobic photographic emulsion dosimeter which were tested for the first time in space . Studies of the mutagenic activity of cosmic-ray particulate radiation environment required measurement of its components with several lithium fluoride thermoluminescent dosimeters and a package of passive nuclear-track detectors capable of recording high-energy multicharge particles . These detectors included cellulose nitrate, Lexan, Ilford G5, and silver chloride crystals . The nuclear track detectors measured the incident heavy particles with the recorded spherical fluences with LET350,H2O>100 keV x micrometers-1 to be 19.3 +/- 1.8 particles cm-2 . This value was found to be lower than that recorded by detectors located in the Biostack and the passive personnel dosimeters worn by the astronauts, suggesting a somewhat greater average shielding.

Compend Contin Educ Dent, 2001 Jul, 22(3 Spec No), 12 - 8
Nutrition: impact on oral and systemic health; Enwonwu CO et al.; Good dietary practices and optimal nutritional status promote growth and tissue development, as well as feature prominently in the prevention of diseases . Malnutrition (particularly protein-energy malnutrition, which invariably involves concurrent deficiencies of the antioxidant micronutrients) promotes salivary gland hypofunction, impaired immunity, and an early shift in the oral microbial ecology toward a preponderance of anaerobic organisms . The immune suppression, which includes impaired cytokine function as well as diminished acute-phase response to infections, impacts negatively on the natural history of inflammatory periodontal diseases . The pathogenesis of oral cancer is influenced by deficiencies of antioxidant nutrients, and there is evidence for diminished DNA methylation, disruption of DNA integrity, and increased DNA damage in folate deficiency.

Nat Rev Immunol, 2002 Mar, 2(3), 151 - 61
Mouse and human dendritic cell subtypes; Shortman K et al.; Dendritic cells (DCs) collect and process antigens for presentation to T cells, but there are many variations on this basic theme . DCs differ in the regulatory signals they transmit, directing T cells to different types of immune response or to tolerance . Although many DC subtypes arise from separate developmental pathways, their development and function are modulated by exogenous factors . Therefore, we must study the dynamics of the DC network in response to microbial invasion . Despite the difficulty of comparing the DC systems of humans and mice, recent work has revealed much common ground.

Immunity, 2002 Mar, 16(3), 429 - 39
In the absence of IL-12, CD4(+) T cell responses to intracellular pathogens fail to default to a Th2 pattern and are host protective in an IL-10(-/-) setting; Jankovic D et al.; IL-12-deficient mice exposed to nonlethal infections with intracellular pathogens or repeatedly immunized with a pathogen extract developed lowered but nevertheless substantial numbers of IFN-gamma(+) CD4(+) T cells compared to those observed in wild-type animals . Moreover, the CD4(+) responses in these knockout animals failed to default to a Th2 pattern . The protective efficacy of the Th1 cells developing in an IL-12-deficient setting was found to be limited by IL-10 since mice doubly deficient in IL-10 and IL-12 survived, while animals deficient in IL-12 alone succumbed to pathogen challenge . In contrast to IL-12 knockout mice, MyD88-deficient animals exposed to a Th1 microbial stimulus developed a pure Th2 response, arguing that this signaling element plays a more critical function than IL-12 in determining pathogen-induced CD4 polarization.

Philos Trans R Soc Lond B Biol Sci, 2002 Feb 28, 357(1418), 165 - 7
Silk: molecular organization and control of assembly; Valluzzi R et al.; The interface between the science and engineering of biology and materials is an area of growing interest . One of the goals of this field is to utilize biological synthesis and processing of polymers as a route to gain insight into topics such as molecular recognition, self-assembly and the formation of materials with well-defined architectures . The biological processes involved in polymer synthesis and assembly can offer important information on fundamental interactions involved in the formation of complex material architectures, as well as practical knowledge into new and important materials related to biomaterial uses and tissue engineering needs . Classic approaches in biology, including genetic engineering, controlled microbial physiology and enzymatic synthesis, are prototypical methods used to control polymer structure and chemistry, including stereoselectivity and regioselectivity, to degrees unattainable using traditional synthetic chemistry . This type of control can lead to detailed and systematic studies of the formation of the structural hierarchy in materials and the subsequent biological responses to these materials.

J Forensic Sci, 2002 Mar, 47(2), 350 - 3
Forensic comparison of soils by bacterial community DNA profiling; Horswell J et al.; This preliminary investigation has shown that a soil microbial community DNA profile can be obtained from the small sample of soil recovered from the sole of a shoe, and from soil stains on clothing . We have also shown that these profiles are representative of the site of collection and therefore could potentially be used as associative evidence to prove a link between suspects and crime scenes . Soil community profiles were obtained using the T-RFLP fingerprinting method that uses fluorescent primer technology and semi-automated analysis techniques similar to those used in human DNA profiling in forensic laboratories.

Mikrobiologiia, 2002 Jan-Feb, 71(1), 89 - 102
{Geochemical characteristics of the carbonate constructions formed during microbial oxidation of methane under anaerobic conditions}; Lein AIu et al.; The aragonite constructions of the Black Sea are formed in a stable anaerobic zone and are a perfect object to study the natural mechanism of anaerobic methane oxidation . The most probable pathway of methane oxidation is its methanogen-mediated reaction with bicarbonates, dissolved in seawater, with the formation of water and acetate, which is then consumed by other components of the anaerobic community . Comparison of the delta 13C values of carbonate minerals and organic matter once more demonstrated that the formation of the organic matter of biomass is accompanied by intense fractionation of carbon isotopes, as a result of which the total organic matter of biomass acquires an extremely light isotopic composition, characterized by delta 13C values as low as -83.8@1000.

Arch Environ Contam Toxicol, 2002 Apr, 42(3), 272 - 9
Determination of toxicokinetic parameters for bioconcentration of water-soluble fraction of petroleum hydrocarbon associated with no . 0 diesel in Changjiang estuary and Jiaozhou bay: model versus mesocosm experiments; Wang X et al.; A method is proposed for determination of toxicokinetic parameters for bioconcentration by phytoplankton of the water-soluble fraction (WSF) of petroleum hydrocarbon (PH) associated with No . 0 diesel, in which WSF-PH concentration in phytoplankton cells, C(A(d)), is estimated by subtracting concentration in water (S-bottle) containing a phytoplankton sample from that in a C-bottle without phytoplankton . It was demonstrated that C(A(d)) agrees well with the concentration found by direct ultrasonication extraction of collected cells, C(A(ind)) ( r = 0.88, p < 0.0001), and its uncertainty was about 17.6% . Mesocosms in 25-m3 ethylene vinyl acetate or 4-m3 polyethylene bags were performed at two sites in China: Changjiang Estuary in spring/summer 1998 and Jiaozhou Bay in autumn 1999 and spring/summer 2000 . The experiments were designed to determine toxicokinetic parameters, including specific rates of uptake and elimination, and bioconcentration factor (BCF), for bioconcentration of WSF-PH by phytoplankton . A modified kinetic two-compartment model for bioconcentration of WSF-PH by phytoplankton was developed to estimate the toxicokinetic parameters . In the model, the influence of phytoplankton growth on bioconcentration and WSF-PH decline due to biotic and abiotic processes other than bioconcentration, such as volatilization, microbial degradation, phytolysis, and sorption expressed as an exponential-decay equation, are taken into account . Size-dependent BCF was observed in the laboratory experiment . BCFs were 1.0 x 10(4) in summer in Changjiang Estuary, 1.6 x 10(4) in summer, and 1.1 x 10(4) in autumn in Jiaozhou Bay . The difference in BCF may be interpreted by its size dependence.

Mutat Res, 2002 Mar 25, 515(1-2), 111 - 24
Effects of heavy metal contamination of soils on micronucleus induction in Tradescantia and on microbial enzyme activities: a comparative investigation; Majer BJ et al.; The aim of this study was to investigate correlation between genotoxic effects and changes of microbial parameters caused by metal contamination in soils . In total, 20 soils from nine locations were examined; metal contents and physicochemical soil parameters were measured with standard methods . In general, a pronounced induction of the frequency of micronuclei (MN) in the Tradescantia micronucleus (Trad-MN) assay was seen with increasing metal concentration in soils from identical locations . However, no correlations were found between metal contents and genotoxicity of soils from different locations . These discrepancies are probably due to differences of the physicochemical characteristics of the samples . Also, the microbial parameters depended on the metal content in soils from identical sampling locations . Inconsistent responses of the individual enzymes were seen in soils from different locations, indicating that it is not possible to define a specific marker enzyme for metal contamination . The most sensitive microbial parameters were dehydrogenase and arylsulfatase activity, biomass C, and biomass N . Statistical analyses showed an overall correlation between genotoxicity in Tradescantia on the one hand and dehydrogenase activity, biomass C, and the metabolic quotient on the other hand . In conclusion, the results of the present study show that the Trad-MN assay is suitable for the detection of genotoxic effects of metal contamination in soils and furthermore, that the DNA-damaging potential of soils from different origin cannot be predicted on the basis of chemical analyses of their metal concentrations.

J Nat Prod, 2002 Mar, 65(3), 278 - 82
Microbial transformations of two lupane-type triterpenes and anti-tumor-promoting effects of the transformation products; Akihisa T et al.; Microbial transformation of betulin (1), a lupane-type triterpene obtained from the bark extract of white birch (Betula platyphylla Sukatshev var . japonica), and its chemical oxidation product, betulonic acid (2), by the fungus Chaetomium longirostre yielded 4,28-dihydroxy-3,4-seco-lup-20(29)-en-3-oic acid (3) and 4-hydroxy-3,4-seco-lup-20(29)-ene-3,28-dioic acid (4) from 1, and 4,7beta,17-trihydroxy-3,4-seco-28-norlup-20(29)-en-3-oic acid (5) and 7 beta,15 alpha-dihydoxy-3-oxolup-20(29)-en-28-oic acid (6) from 2 . The four metabolites, 3-6, along with 1 and 2, were evaluated for their inhibitory effects on Epstein-Barr virus early antigen (EBV-EA) activation induced by the tumor promoter 12-O-tetradecanoylphorbol-13-acetate (TPA) in Raji cells as a primary screening test for inhibitors of tumor promotion . All of the triterpenes tested showed potent inhibitory effects, with the four metabolites 3-6 exhibiting the more potent effects.

J Nat Prod, 2002 Mar, 65(3), 273 - 7
Microbial transformations of isosteviol; Hsu FL et al.; Microbial transformations of the tetracyclic diterpenoid isosteviol (ent-16-ketobeyeran-19-oic acid) (2) have revealed that isosteviol is metabolized by Cunninghamella bainieri, Actinoplanes sp., Mucor recurvatus, and Cunninghamella blakesleeana to yield five new metabolites, ent-11alpha,12alpha-dihydroxy-16-ketobeyeran-19-oic acid (5), ent-11alpha,12alpha,17-trihydroxy-16-ketobeyeran-19-oic acid (6), ent-12alpha,15alpha-dihydroxy-16-ketobeyeran-19-oic acid (7), ent-7alpha,15alpha-dihydroxy-16- ketobeyeran-19-oic acid (8), and ent-9alpha-hydroxy-16-ketobeyeran-19-oic acid (9), together with three known metabolites, ent-7alpha-hydroxy-16-ketobeyeran-19-oic acid (3), ent-7beta-hydroxy-16-ketobeyeran-19-oic acid (4), and ent-12alpha-hydroxy-16-ketobeyeran-19-oic acid (10) . The structures of these metabolites were established on the basis of HRFABMS and 1D and 2D NMR spectral data . In addition, metabolites 3-10 were tested for antihypertensive activity and were found to be less active than the parent compound 2.

J Rheumatol, 2002 Mar, 29(3), 522 - 6
Interleukin 1beta (IL-1beta), IL-10, tumor necrosis factor-alpha, and cellular proliferation index in peripheral blood mononuclear cells in patients with ankylosing spondylitis; Vazquez-Del MM et al.; OBJECTIVE: To evaluate cytokine production and cellular proliferation index (CPI) in peripheral blood mononuclear cells (PBMC) of patients with ankylosing spondylitis (AS), and their association with clinical variables . METHODS: In a cross sectional study we compared the production of tumor necrosis factor-alpha (TNF-alpha), interleukin 1beta (IL-1beta), and IL-10 and CPI in response to phytohemagglutinin (PHA) in PBMC of 27 patients with AS and 24 healthy controls . We also assessed clinical characteristics including disease activity index (BASDAI) and functional index (BASFI) . RESULTS: Levels of IL-1beta were higher in patients with AS (median 242 pg/ml) than in controls (median 65 pg/ml); p = 0.002 . No differences were observed in median levels of TNF-alpha or IL-10 between AS and controls . Patients had a reduction in CPI (1.2 in AS vs 1.8 in controls; p < 0.001) . A positive correlation was observed between IL-10 production and age (rho = 0.34, p = 0.01) . A borderline negative correlation was observed between CPI and age (rho = -0.26, p = 0.07) . CONCLUSION: Patients with AS had high production of IL-1beta compared with controls and a poor response in CPI . These findings may explain the lack of response for microbial antigens mediated by the innate immune response.

Dev Comp Immunol, 2002 Jun, 26(5), 461 - 9
Activation of carp leukocytes by a galactose-binding protein from Aphanomyces piscicida; Kurata O et al.; This study demonstrated that a galactose-binding protein (GBP) produced by a fish pathogenic water mold, Aphanomyces piscicida, activates carp leukocytes . Leukocytes were separated from the head kidney and peripheral blood using Percoll density centrifugation . A flow cytometric analysis revealed that GBP binds with many cells and a variety of cell types including lymphocytes, granulocytes and thrombocytes . Intracellular calcium flux of the peripheral blood leukocytes induced by stimulation with GBP was confirmed by counting the fluo-3 loaded cells whose fluorescence increased after the stimulation using flow cytometry . The percentage of cells in which a calcium flux was induced peaked 1 min after the stimulation . Approximately 6% of the cells specifically responded 1 min after the stimulation . The proliferation response was determined by the level of BrdU uptake by the leukocytes after the stimulation . Cell proliferation was observed 2, 4 and 6 days after stimulation with GBP . The expression of cytokines IL-1beta and TGF-beta1 in the peripheral blood leukocytes, after the stimulation was evaluated by a semi-quantitative reverse-transcriptase polymerase chain reaction . Increased expression of IL-1beta was observed 4h after stimulation with GBP . Variation of TGF-beta1 expression under the same conditions was not observed . The kinetics of intracellular calcium flux and the level of IL-1beta expression induced by GBP stimulation were different from those induced by phytohemagglutinin stimulation . These results confirmed that GBP is a pathogenic microbial component that can induce cell activation . GBP seems to induce the inflammatory response observed in the Aphanomyces infection.

J Anim Physiol Anim Nutr (Berl), 2001 Dec, 85(11-12), 420 - 30
Hydrolysis of phytic acid by intrinsic plant and supplemented microbial phytase (Aspergillus niger) in the stomach and small intestine of minipigs fitted with re-entrant cannulas . 3 . Hydrolysis of phytic acid (IP6) and occurrence of hydrolysis products (IP5, IP4, IP3 and IP2); Rapp C et al.; Hydrolysis of phytate in the stomach and the small intestine as influenced by intrinsic plant (wheat) and supplemented microbial phytase (Aspergillus niger) were investigated with six minipigs (40-50 kg initial body weight) fitted with re-entrant cannulas in the duodenum, 30 cm posterior to the pylorus (animals 1, 4, 5 and 6) and ileocecal re-entrant cannulas, 5 cm prior the ileocecal junction (animals 1, 2 and 3), respectively . Dietary treatments were as follows: (1) diet 1, a corn-based diet {43 U phytase/kg dry matter (DM)}; (2) diet 2, diet 1 supplemented with microbial phytase (818 U/kg DM); and (3) diet 3, a wheat-based diet (1192 U/kg DM) . At 07 30 h and 19 30 h, each animal was fed 350 g diet mixed with 1050 ml de-ionized water . Digesta were collected continuously and completely during a 12-h period after feeding . Mean hydrolysis rates of IP6 in the stomach as measured at the proximal duodenum of animals 1, 4, 5 and 6 were 9.0, 77.2 and 66.2% for diet 1, 2 and 3, respectively . Microbial phytase was much more effective in phytate hydrolysis than wheat phytase . Mean IP6 hydrolysis rates of the respective diets in the stomach and small intestine as measured at the distal ileum of animals 1, 2 and 3 were 19.0, 62.6 and 64.6% and were lower than treatment means of the stomach only . Differences existed between experimental animals with respect to their ability to hydrolyse IP6 in the stomach independent of the presence and source of dietary phytase . Considerable amounts of hydrolysis products occurred in both the duodenal and ileal digesta when diets 2 and 3 were fed; however, only traces were determined after ingestion of diet 1 . Independent of dietary treatment, four IP5 isomers were detected, but in different amounts.

J Anim Physiol Anim Nutr (Berl), 2001 Dec, 85(11-12), 414 - 9
Hydrolysis of phytic acid by intrinsic plant and supplemented microbial phytase (Aspergillus niger) in the stomach and small intestine of minipigs fitted with re-entrant cannulas . 2 . Phytase activity; Rapp C et al.; Hydrolysis of phytate in the stomach and the small intestine as influenced by intrinsic plant (wheat) and supplemented microbial phytase (A . niger) were investigated with six minipigs (40-50 kg initial BW) fitted with re-entrant cannulas in the duodenum, 30 cm posterior to the pylorus (animals 1, 4, 5, and 6) and ileocecal re-entrant cannulas, 5 cm prior the ileocecal junction (animals 1, 2, and 3), respectively . Dietary treatments were as follows: (1) diet 1, a corn-based diet (43 U phytase/kg DM); (2) diet 2, diet 1 supplemented with microbial phytase (818 U/kg DM) and (3) diet 3, a wheat-based diet (1192 U/kg DM) . At 0730 and 1930 per animal 350 g diet mixed with 1050 ml de-ionized water were fed . Digesta were collected continuously and completely during 12 h after feeding.In the duodenal digesta, 70% of the microbial phytase (diet 2) and 45% of the wheat phytase (diet 3) were recovered within 12 h after ingestion of the phytases, whereas only negligible amounts were detected in the digesta of pigs fed the phytase-poor corn-based diet 1 . Most phytase activity passed through the stomach within the first hour after feeding.Microbial phytase activity at pH 2.8 was less sensitive to acidic pHs, such as those found in the stomach, than phytase activity at pH 5.3.Phytase activities in the digesta of the distal ileum did not depend either on source or amount of dietary phytase activity.

J Anim Physiol Anim Nutr (Berl), 2001 Dec, 85(11-12), 406 - 13
Hydrolysis of phytic acid by intrinsic plant or supplemented microbial phytase (Aspergillus niger) in the stomach and small intestine of minipigs fitted with re-entrant cannulas; Rapp C et al.; Hydrolysis of phytate in the stomach and the small intestine as influenced by intrinsic plant (wheat) and supplemented microbial phytase (A . niger) were investigated with six minipigs (40-50 kg initial BW) fitted with re-entrant-cannulas in the duodenum, 30 cm posterior to the pylorus (animals 1, 4, 5, and 6) and ileocecal re-entrant cannulas, 5 cm prior the ileocecal junction (animals 1, 2, and 3), respectively . Dietary treatments were as follows: (1) diet 1, a corn-based diet (43 U Phytase/kg DM); (2) diet 2, diet 1 supplemented with microbial phytase (818 U/kg DM) and (3) diet 3, a wheat-based diet (1192 U/kg DM) . At 0730 and 1930 per animal 350 g diet mixed with 1050 ml de-ionized water were fed . Digesta were collected continuously and completely during 12 h after feeding . Duodenal recovery of dry matter and total phosphorus were 100% in the period between two feedings, irrespective of dietary treatment . In animals fed the wheat-based diet, dry matter left the stomach faster (p < 0.05) during the first hour after feeding than in animals fed the corn-based diets (41.3 vs . 31.0 and 25.8% of intake, respectively) . Supplemented microbial phytase did not affect ileal dry matter digestibility of the corn-based diet . In the first hour after feeding, phosphorus concentration of the duodenal digesta of animals fed corn-based diets with or without supplemented microbial phytase (5.86, 6.19 mg total P/g DM) exceeded the dietary level considerably (4.30 and 4.21 mg total P/g DM) indicating a higher solubility of corn than wheat phosphorus in the stomach . Apparent ileal P absorption was higher (p < 0.05) in the wheat-based diet (37.6%) and corn-based diet supplemented with microbial phytase (34.3%) than in the unsupplemented corn-based diet (17.6%).

Nat Rev Immunol, 2001 Oct, 1(1), 41 - 9
Natural killer cells, viruses and cancer; Cerwenka A et al.; Natural killer cells are innate immune cells that control certain microbial infections and tumours . The function of natural killer cells is regulated by a balance between signals transmitted by activating receptors, which recognize ligands on tumours and virus-infected cells, and inhibitory receptors specific for major histocompatibility complex class I molecules . Here, we review the emerging evidence that natural killer cells have an important role in vivo in immune defence.

J Microsc, 2001 Dec, 204(Pt 3), 258 - 62
Confocal laser scanning microscopy as a tool to determine cyanobacteria biomass in microbial mats; Sole A et al.; We have developed a method based on confocal laser scanning microscopy for detection and quantification of cyanobacteria from the Ebro Delta microbial mats . Cyanobacteria play a major role as primary producers in microbial mats; it is difficult, however, to apply classical methods to estimate their biomass because they establish strong interactions with detritic particles . The protocol described here allows the localization of individual cells or filaments with micrometre precision without the need to either manipulate or stain the samples . This method is suitable for studying biomass 'in situ' in microbial mats.

Insect Mol Biol, 2001 Dec, 10(6), 561 - 71
Regulation of midgut defensin production in the blood-sucking insect Stomoxys calcitrans; Munks RJ et al.; The Stomoxys midgut defensin (Smd) family of genes are exclusively expressed in the anterior midgut of adult flies . Their putative function is protection of the stored bloodmeal from microbial attack . Smd genes are constitutively expressed, up-regulated in response to a bloodmeal and further up-regulated by immune stimulation per os but only in the presence of a bloodmeal not a sugar meal . Smd genes are down-regulated in response to a systemic immune challenge . Smd gene constructs transfected into l(2)mbn cells undertake constitutive expression but are not up-regulated by immune challenge . Electrophoretic mobility shift assays (EMSA) suggest the rel-like sites in the proximal promoter region of Smd genes do not bind midgut factors and so are non-functional.

Immunol Cell Biol, 2001 Dec, 79(6), 537 - 46
DNA vaccines: future strategies and relevance to intracellular pathogens; Sharma AK et al.; Increasing awareness of microbial threat has rekindled interest in the great potential of vaccines for controlling infectious diseases . The fact that diseases caused by intracellular pathogens cannot be overcome by chemotherapy alone has increased our interest in the generation of highly efficacious novel vaccines . Vaccines have proven their efficacy, as the immunoprotection they induce appears to be mediated by long-lived humoral immune responses . However, there are no consistently effective vaccines available against diseases such as tuberculosis and HIV, and other infections caused by intracellular pathogens, which are predominantly controlled by T lymphocytes . This review describes the T-cell populations and the type of immunity that should be activated by successful DNA vaccines against intracellular pathogens . It further discusses the parameters that need to be fulfilled by protective T-cell Ag . We then discuss future approaches for DNA vaccination against diseases in which cell-mediated immune responses are essential for providing protection.

Acta Anaesthesiol Scand, 2002 Jan, 46(1), 17 - 23
Effective inhibition of nitric oxide production by aminoguanidine does not reverse hypotension in endotoxaemic rats; Metcalf K et al.; BACKGROUND: Excess production of nitric oxide (NO) by the inducible NO synthase (iNOS) has been implicated in the pathophysiology of septic shock . Using methaemoglobin (metHb) and the stable NO metabolite nitrate as markers of NO formation, we assessed the effect of iNOS blockade by aminoguanidine (AG) on hypotension and NO formation in endotoxaemic rats . METHODS: In 32 male Wistar rats under chloralose anaesthesia, MetHb (at 15 and 330 min, respectively) and plasma nitrate (at 330 min) were determined . Mean arterial pressure, heart rate and haematocrit were monitored . The LPS group (n=8) received bacterial endotoxin (LPS), 3 mg kg(-1) i.v . and was subsequently monitored for 5 h . At 2 h after LPS, the LPS+AG20 group (n=8) received AG, 5 mg kg(-1), and 5 mg kg(-1) h(-1) for the remaining 3 h . The LPS+AG100 group (n=8) instead received 25 mg kg(-1), followed by 25 mg kg(-1) h(-1) . The NaCl group (n=8) was given corresponding volumes of isotonic saline . RESULTS: AG decreased the LPS-induced rise in plasma nitrate by about 50% in the LPS+AG20 group . MetHb levels, however, were not appreciably reduced by this dose . Both NO metabolites reached control levels after the higher dose of AG . LPS caused a progressive decrease in haematocrit . AG did not influence the LPS-induced hypotension, tachycardia or haemodilution . CONCLUSION: AG inhibited NO formation in a dose-dependent way . Yet, AG had no haemodynamic effects, suggesting a minor cardiovascular influence of iNOS in this endotoxin model, in parallel to what has been found in microbial sepsis.

Nat Rev Cancer, 2002 Jan, 2(1), 28 - 37
Helicobacter pylori and gastrointestinal tract adenocarcinomas; Peek RM Jr et al.; Although gastric adenocarcinoma is associated with the presence of Helicobacter pylori in the stomach, only a small fraction of colonized individuals develop this common malignancy . H . pylori strain and host genotypes probably influence the risk of carcinogenesis by differentially affecting host inflammatory responses and epithelial-cell physiology . Understanding the host-microbial interactions that lead to neoplasia will improve cancer-targeted therapeutics and diagnostics, and provide mechanistic insights into other malignancies that arise within the context of microbially initiated inflammatory states.

Scand J Immunol, 2001 Dec, 54(6), 543 - 50
Importance of CpG dinucleotides in activation of natural IFN-alpha-producing cells by a lupus-related oligodeoxynucleotide; Magnusson M et al.; The oligodeoxyribonucleotide (ODN) 5'-TTTTCAATTCGAAGATGAAT-3' (ODN H), identified in systemic lupus erythematosus (SLE) serum, induced the production of interferon (IFN)-alpha in human peripheral blood mononuclear cells (PBMC) when combined with lipofectin . Flow cytometric analysis with staining for surface antigens and intracellular IFN-alpha, showed that the IFN-alpha-producing cells (IPC) were the natural IPC, also termed type 2 dendritic cell precursors (pDC2) or plasmacytoid monocytes . The importance of unmethylated CpG dinucleotides for the interferogenic activity of ODN was studied . Methylation of CpG impaired the activity of single-stranded (ss) ODN H, but increased that of the complementary ssODN I . Furthermore, CpG-methylated double-stranded (ds) ODN Hmet-Imet lost, but hemimethylated dsODN H-Imet retained interferogenic activity . Inversion of the CpG to GpC had no effect on the interferogenic activity of ssODN H, increased that of ssODN I, however abolished the activity of dsODN H-I . Alteration of the CpG in ODN H to ApG and in the ODN I to CpT destroyed their activity . The induction of IFN-alpha is therefore sequence-specific, but unmethylated CpGs are not always required, especially not in ssODNs . Interferogenic DNA sequences could therefore be more frequent in eukaryotic genomes than previously thought and their capacity to activate natural IPC may have implications for immune responses to microbial antigens and nuclear autoantigens.

Cytokine Growth Factor Rev, 2002 Apr, 13(2), 95 - 109
The roles of IFN gamma in protection against tumor development and cancer immunoediting; Ikeda H et al.; Interferon-gamma (IFN gamma) is a cytokine that plays physiologically important roles in promoting innate and adaptive immune responses . The absence of IFN gamma production or cellular responsiveness in humans and experimental animals significantly predisposes the host to microbial infection, a result that validates the physiologic importance of this cytokine in preventing infectious disease . Recently, an additional role for IFN gamma in preventing development of primary and transplanted tumors has been identified . Although there now appears to be a consensus that IFN gamma promotes host responses to tumors, the mechanisms by which this cytokine achieves its effects remain unclear . In this review, we briefly discuss key issues of the molecular cell biology of IFN gamma and its receptor that are most relevant to IFN gamma-dependent anti-tumor effects and then focus on the data implicating IFN gamma as a critical immune system component that regulates tumor development . Potential mechanisms underlying IFN gamma's anti-tumor effects are discussed and a preliminary integrative model of IFN gamma's actions on tumors is proposed . Finally, the capacity of IFN gamma and lymphocytes to not only provide protection against tumor development but also to sculpt the immunogenic phenotype of tumors that develop in an immunocompetent host is presented and introduced as a "cancer immunoediting" process.

Biosci Rep, 2001 Aug, 21(4), 445 - 61
Contact lens related corneal infections; Willcox MD et al.; This article describes microbial keratitis, infection of the cornea by micro-organisms . Contact lens wear is a predisposing factor for the development of microbial keratitis . Micro-organisms probably adhere to the contact lens, transfer from the contact lens to a damaged or compromised corneal epithelial surface, penetrate into the deeper layers of the cornea and produce corneal damage . Host responses to the invading micro-organisms, while designed to protect the eye, can often exacerbate the situation and the resulting microbial keratitis can lead to permanent blindness . The microbial, biochemical and immunological aspects of MK will be described in detail.

Folia Microbiol (Praha), 2001, 46(6), 555 - 8
Coprophilous streptomycetes and fungi--food sources for enchytraeid worms (Enchytraeidae); Kristufek V et al.; Food selection experiments demonstrated that Enchytraeus crypticus (Oligochaeta, Enchytraeidae) was attracted by Streptomyces species and microscopic fungi in vermiculture substrates and in the gut content of Eisenia andrei earthworms . Consumption of spores and/or mycelia of attractive strains influenced markedly the proliferation of E . crypticus . There was a 74-fold increase in the numbers of enchytraeids fed on the mixture of Aspergillus flavus and Verticillium tenerum mycelia or on mycelium of one strain of Streptomyces in reproduction tests . Lower rates of increase of E . crypticus (50-fold or less) were observed in variants where V . tenerum or mixtures of fungi and streptomycetes were offered as food . We showed a potential importance of microbial populations in vermicultures and indicated that their regulation may provide a way to increase the productivity of such systems.

Int J Pharm, 2002 Feb 21, 233(1-2), 239 - 52
Preparation and characterization of sterile and freeze-dried sub-200 nm nanoparticles; Konan YN et al.; The feasibility of producing sterile and freeze-dried polyester nanoparticles was investigated . Various poly(D,L-lactide-co-glycolide) and poly(D,L-lactide) were selected as biodegradable polymers . Using the salting-out procedure, process parameters were optimized to obtain sub-200 nm particles . After purification, the nanoparticle suspensions containing different lyoprotectants were sterilized by filtration . Freeze-drying was performed using vials covered with 0.22 microm membrane filters in order to preserve the suspensions from bacterial contamination . Sterility was assessed on the final product according to pharmacopoeial requirements using the membrane filtration method . With all polymers tested, sub-200 nm particles could be obtained . Nanoparticles with a size as low as 102 nm were prepared with good reproducibility and narrow size distribution . Upon freeze-drying, it appeared that complete redispersion of all types of polyester nanoparticles could be obtained in presence of the lyoprotectants tested such as saccharides while aggregation was observed without lyoprotectant . Sterility testing showed no microbial contamination indicating that sterile nanoparticulate formulations have been achieved.

Transfusion, 2002 Jan, 42(1), 10 - 7
Processing of peripheral blood progenitor cell components in improved clean areas does not reduce the rate of microbial contamination; Cassens U et al.; BACKGROUND: Microbial contamination of peripheral blood progenitor cell components (PBPCs) may cause severe complications in immunosuppressed recipients . Therefore, principles of Good Manufacturing Practice (GMP) are applicable for processing of PBPC components to reduce potential risks of contamination . STUDY DESIGN AND METHODS: It was investigated in a retrospective study whether the microbial contamination of PBPC components could be reduced after processing in improved clean areas according to the "Manufacture of Sterile Medicinal Products." Starting in 1994, a total of 1478 autologous and allogeneic PBPC components have been collected and processed into 3149 cryopreservation bags at the Department of Transfusion Medicine . Sterility testing was performed for all bags . Until December 1998, 783 PBPC components were processed at a clean bench only (group I) . Thereafter, 695 PBPC components have been processed at a clean bench located in a clean area with an airlock system for personnel and equipment (group II) . RESULTS: In group I, 16 of 1555 bags (1.03%) showed positive results in the first sterility testing . In group II, 21 of 1594 bags (1.32%) were positive (p = NS) . The clinical follow-up was inconspicuous . CONCLUSION: Microbial contamination of PBPC components could not be reduced by installation of improved clean area conditions.

J Periodontol, 2002 Feb, 73(2), 231 - 47
A critical assessment of interleukin-1 (IL-1) genotyping when used in a genetic susceptibility test for severe chronic periodontitis; Greenstein G et al.; BACKGROUND: This review addresses the ability of a commercially available genetic susceptibility test to determine the risk of developing severe chronic periodontitis . The test is used to detect the simultaneous occurrence of allele 2 at the IL-1A+4845 and IL-1B+3954 loci . If both of these polymorphisms are present, patients are referred to as being genotype-positive and considered predisposed to becoming afflicted with severe chronic periodontitis . A basic premise of this test is the assumption that individuals who are genotype-positive produce increased amounts of IL-beta in response to microbial lipopolysaccharides, which allegedly predisposes them to an exaggerated inflammatory response and an increased incidence of chronic periodontitis . METHODS: Controlled clinical trials were selected that evaluated the ability of the genetic test to predict which patients were susceptible to bleeding upon probing, periodontitis, peri-implantitis, and tooth loss . RESULTS: Comparison of results from test (genotype-positive) and control groups (genotype-negative) revealed that there is ambiguity with regard to predicting which patients will manifest elevated sub-gingival levels of IL-beta . Similarly, it is questionable if the test is able to forecast which individuals will demonstrate an increased occurrence of bleeding upon probing, diminished clinical attachment, decreased osseous support, or loss of teeth . CONCLUSIONS: There are many unanswered questions concerning the utility of detecting allele 2 at the IL-1A+4845 and IL-IB+3954 loci to foretell which patients will develop severe chronic periodontitis . Therefore, clinicians must cautiously interpret results obtained with the commercially available genetic susceptibility test before they alter maintenance schedules or treatment regimens of symptomatic or asymptomatic patients.

Cell, 2002 Mar 8, 108(5), 583 - 6
Microbial minimalism: genome reduction in bacterial pathogens; Moran NA; When bacterial lineages make the transition from free-living or facultatively parasitic life cycles to permanent associations with hosts, they undergo a major loss of genes and DNA . Complete genome sequences are providing an understanding of how extreme genome reduction affects evolutionary directions and metabolic capabilities of obligate pathogens and symbionts.

Chem Rec, 2001, 1(2), 152 - 61
Hydratases involved in nitrile conversion: screening, characterization and application; Yamada H et al.; The discovery of new enzymes with greater activity and specificity opens new, simple routes for synthetic processes, and consequently, new methods to solve environmental problems . A number of nitrile-related enzymes have been screened over the past few years for use in developing synthetic applications . Microbial nitrile hydratase (NHase) has great potential as a catalyst in organic chemical processing because the enzyme can convert nitriles to the corresponding higher value amides under mild conditions, and has now been applied to the industrial productions of acrylamide and nicotinamide . Particularly, the former production is the first successful example of a bioconversion process for the manufacture of a commodity chemical . The characterization of the enzyme at the molecular level has provided new insights into how the molecular structure determines the enzyme function, and how the regulatory system controls the expression of the enzyme genes to improve the enzyme and the NHase-dependent process.

Lancet Infect Dis, 2002 Jan, 2(1), 18 - 24
Novel methods for the detection of microbial antibodies in oral fluid; McKie A et al.; Compared with blood, oral fluid has several advantages as a sample for antibody detection . It is simple, safe, painless, and cheap to collect . The only drawback is that while the antibody profiles indicate those in blood, they are at lower concentrations . Antibody capture assays are the method of choice for the detection of microbial antibodies in oral fluid, but their relative lack of sensitivity when based on conventional immunoassay techniques has mostly limited their use to epidemiological applications . Immuno-PCR and time-resolved fluorescence offer more sensitive detection systems that could be applied to oral fluid specimens . We review antibody detection in oral fluid and discuss immuno-PCR and time-resolved fluorescence as candidate systems . Both have the potential to broaden the applications of oral fluid testing to clinical diagnostics.

J Anim Sci, 2002 Mar, 80(3), 812 - 7
Effects of restricted and ad libitum intake of diets containing wheat middlings on site and extent of digestion in steers; Hermesmeyer GN et al.; A 5 x 5 Latin square design was used to determine the effects of restricted and ad libitum intake of diets containing wheat middlings on the site and extent of digestion compared to ad libitum intake of a corn-based diet and ad libitum intake of chopped alfalfa hay . Five ruminally and duodenally cannulated Angus steers (519 +/- 41.5 kg BW) were used to compare five dietary treatments . The five treatments were as follows: ad libitum access to a corn-based finishing diet (control), the control diet with 25 percentage units of the corn and soybean meal replaced with wheat middlings offered ad libitum (WM), the WM diet restricted to 75% of predicted ad libitum intake (RWM), the RWM diet with wheat middlings replaced with ammoniated wheat middlings (RNWM), and ad libitum access to a chopped alfalfa hay diet . Although RWM steers were fed to consume 75% of ad libitum intake, RWM steers consumed 15.5% less DM than WM . Steers fed ad libitum hay consumed 28.6, 31.7, and 37.2% less (P < 0.01) DM, OM, and nitrogen than RWM steers . No differences in apparent or true ruminal digestibility were observed among steers fed the control vs WM, WM vs RWM, RWM vs RNWM, or RWM vs hay diets . However, the steers fed the hay diet had 32.5, 33.4, and 36.9% lower (P < 0.01) apparent total tract digestibilities of DM, OM, and N than those fed the RWM diet . Average ruminal pH was lower (P < 0.01) for control steers than those fed the WM diet and for those fed RWM compared to the hay diet . The acetate:propionate ratio was higher for cattle fed hay vs the RWM diet . Microbial DM and OM flow to the small intestine was higher (P < 0.02) for steers fed the RWM diet than those fed the hay diet . In addition, bacterial N flow to the small intestine was higher (P < 0.01) for cattle receiving the RWM diet than the hay diet . Feeding diets containing 25 percentage units of wheat middlings at 75% ad libitum intake had no effect on ruminal digestibility.

Can J Microbiol, 2002 Jan, 48(1), 14 - 20
Effect of a fibrolytic enzyme preparation from Trichoderma longibrachiatum on the rumen microbial population of dairy cows; Nsereko VL et al.; The effects of supplementing a dairy cow diet with incremental levels of a fibrolytic enzyme preparation (preparation B) from Trichoderma longibrachiatum on the rumen microbial population were investigated . Two cows fitted with rumen cannulae were each fed a diet containing barley-based concentrate (52%), maize silage (29%), and chopped alfalfa hay (19%), supplemented with 0, 1, 2, 5, or 10 L of preparation B per tonne of dry matter (DM) . Preparation B stimulated numbers of total viable bacteria in a quadratic manner (P < 0.05), to approximately 230, 330, 390, and 250% at 1, 2, 5, and 10 L x t(-1) DM, respectively . Preparation B increased the numbers of cellobiose-utilizing (P < 0.01), xylanolytic (P < 0.05), and amylolytic bacteria (P < 0.05), but had no effect (P > 0.05) on numbers of cellulolytic bacteria . However, when bacterial numbers enumerated on each substrate were expressed as a proportion of total viable bacterial numbers, only cellobiose utilizers were stimulated, and this stimulation was limited to the 1 L x t(-1) DM level of preparation B (P < 0.05) . The results of this study demonstrate that the inclusion of an exogenous fibrolytic enzyme preparation in dairy cow diets increased the numbers of rumen bacteria that utilize hemicelluloses and secondary products of cellulose digestion.

Trop Anim Health Prod, 2002 Feb, 34(1), 49 - 64
Effect of cowpea hay, groundnut hay, cotton seed meal and maize meal supplementation to maize stover on intake, digestibility, microbial protein supply and acetate kinetics in weaner lambs; Chakeredza S et al.; Ten weaner lambs were used in a double 5 x 5 Latin square design to evaluate the effect of supplementing maize stover (MS) with cowpea hay (CW), groundnut hay (GN), cotton seed meal (CSM) or maize meal (MM) on the intake, digestion kinetics and acetate clearance rate . CW and GN were offered at 30% w/w to MS, while CSM and MM were given at 15 g/kg0.75 per day . Supplementation reduced (p < 0.01) MS intake but enhanced (p < 0.01) total dry matter intake . There were no significant differences (p > 0.05) in digestibility . However, the estimated ME intake was significantly (p < 0.05) improved by supplementation . The estimated microbial protein supply was almost significantly (p < 0.06) improved by 22.68%, 5.35%, 17.58% and 47.90% on the CW-, GN-, CSM- and MM-supplemented diets, compared to the control (7.85 g/day) . Microbial protein synthesis efficiency was not significantly affected (p > 0.05) by diet, and nor were the acetate clearance rates (p > 0.05), which averaged 0.0475 +/- 0.0078/min . The improvement in ME intake may have been due to a faster flow rate of digesta and a better balance of nutrients in the end-products of digestion . These results demonstrate that small amounts of forage supplements can improve nutrient intake when animals consume low-quality forages and provide a basis for comparing such supplements with bought-in protein and energy supplements.

J Hosp Infect, 2002 Mar, 50(3), 196 - 201
Recurrent Sphingomonas paucimobilis -bacteraemia associated with a multi-bacterial water-borne epidemic among neutropenic patients; Perola O et al.; A cluster of septicaemias due to several water-related species occurred in a haematological unit of a university hospital . In recurrent septicaemias of a leukaemic patient caused by Sphingomonas paucimobilis, genotyping of the blood isolates by use of random amplified polymorphic DNA-analysis verified the presence of two distinct S . paucimobilis strains during two of the separate episodes . A strain of S . paucimobilis identical to one of the patient's was isolated from tap water collected in the haematological unit . Thus S . paucimobilis present in blood cultures was directly linked to bacterial colonization of the hospital water system . Heterogeneous finger-printing patterns among the clinical and environmental isolates indicated the distribution of a variety of S . paucimobilis clones in the hospital environment . This link also explained the multi-microbial nature of the outbreak .

Sci Total Environ, 2002 Mar 8, 286(1-3), 51 - 9
Assessment of bioavailable arsenic and copper in soils and sediments from the Antofagasta region of northern Chile; Flynn HC et al.; Copper levels of nearly 500 mg l(-1) were measured in aqueous extracts of soil and sediment samples from the lowlands of Antofagasta . Arsenic levels of up to 183 mg l(-1) were found in river sediments, and 27.5 mg l(-1) arsenic was found at the location of a dam where potable water is extracted . This indicates that the arsenic contamination of water supplies reported recently for the pre-Andes may be a widespread problem throughout the region . Copper contamination from smelting activities also provides cause for concern as elevated levels were found in aqueous extracts of soil up to 20 km away from a smelter . This study went beyond traditional chemical analysis by assessing the potential benefits of using microbial biosensors as an alternative to determination of chemical speciation, to provide an environmentally relevant interpretation of soil/sediment residue levels . This approach is simple to use and enables a rapid, low cost assessment of pollutant bioavailability . It may, therefore, be of use for further investigations in the region and beyond.

Sci Total Environ, 2002 Mar 8, 286(1-3), 15 - 25
Effect of alcohol addition on the movement of petroleum hydrocarbon fuels in soil; Adam G et al.; Groundwater contamination by fuel spills from aboveground and underground storage tanks has been of growing concern in recent years . This problem has been magnified by the addition of oxygenates, such as ethanol and methyl-tertiary-butyl ether (MTBE) to fuels to reduce vehicular emissions to the atmosphere . These additives, although beneficial in reducing atmospheric pollution, may, however, increase groundwater contamination due to the co-solvency of petroleum hydrocarbons and by the provision of a preferential substrate for microbial utilisation . With the introduction of ethanol to diesel fuel imminent and the move away from MTBE use in many states of the USA, the environmental implications associated with ethanol additive fuels must be thoroughly investigated . Diesel fuel movement was followed in a 1-m soil column and the effect of ethanol addition to diesel fuel on this movement determined . The addition of 5% ethanol to diesel fuel was found to enhance the downward migration of the diesel fuel components, thus increasing the risk of groundwater contamination . A novel method using soil packed HPLC columns allowed the influence of ethanol on individual aromatic hydrocarbon movement to be studied . The levels of ethanol addition investigated were at the current additive level (approx . 25%) for ethanol additive fuels in Brazil and values above (50%) and below (10%) this level . An aqueous ethanol concentration above 10% was required for any movement to occur . At 25% aqueous ethanol, the majority of hydrocarbons were mobilised and the retention behaviour of the soil column lessened . At 50% aqueous ethanol, all the hydrocarbons were found to move unimpeded through the columns . The retention behaviour of the soil was found to change significantly when both organic matter content and silt/clay content was reduced . Unexpectedly, sandy soil with low organic matter and low silt/clay was found to have a retentive behaviour similar to sandy subsoil with moderate silt/clay, but little organic matter . It was concluded that sand grains might have a more important role in the adsorption of petroleum hydrocarbons than first realised . This method has shown that soil packed HPLC columns can be used to provide a quick estimate of petroleum hydrocarbon, and possibly other organic contaminant, movement in a variety of different soil types.

Life Sci Space Res, 1964, 2, 407 - 32
Problems in sterilization of unmanned space vehicles; Jaffe LD; The probability of achieving and maintaining sterility of an unmanned spacecraft with varied suggested procedures is examined in detail, as are alternative techniques for avoiding biological contamination of the planets . The required degree of assurance against contamination of Mars, Venus and the Moon with Earth organisms is also considered . For Mars landers and orbiters, sterilization of the spacecraft or capsule by dry heat, with no subsequent access, is found to be desirable . For the present, sterilization of Venus landers still seems desirable . For Mars flybys, and for Venus orbiters and flybys, control of the trajectory to minimize the chance of unintentionally entering the planetary atmosphere appears the method of choice . For the Moon, sterilization seems unnecessary, but microbial counts should be kept low . Sterilization lowers spacecraft and system reliability . It reduces the chance of launching within periods fixed by astronomical constraints and increases costs . The gain which should be achieved through spacecraft sterilization, in return of significant biological information about the planets, must be balanced against these losses . In particular, one should keep in mind the loss in return of biological data occasioned by failure of a spacecraft to fulfill its mission; the probability of such failure is increased by sterilization.

J Nutr, 2002 Mar, 132(3), 514S - 516S
Transgenic approaches in commonly consumed cereals to improve iron and zinc content and bioavailability; Holm PB et al.; Modern genetic and molecular technologies provide a number of tools that can be utilized for the development of staple foods with a higher iron and zinc content and improved bioavailability of these minerals . This article summarizes current strategies aimed at increasing the iron-sequestering capacity of the endosperm and improving mineral bioavailability via in planta synthesis of microbial phytases . A case study is presented for wheat, and future strategies are discussed addressing the importance of phytase thermostability.

J Agric Food Chem, 2002 Mar 13, 50(6), 1330 - 4
NMR-based screening method for transglutaminases: rapid analysis of their substrate specificities and reaction rates; Shimba N et al.; Incorporation of inter- or intramolecular covalent cross-links into food proteins with microbial transglutaminase (MTG) improves the physical and textural properties of many food proteins such as tofu, boiled fish paste, and sausage . Other transglutaminases (TGases) are expected to be used in the same way, and also to extend the scope of industrial applications to materials, drugs, and so on . The TGases have great diversity, not only in amino acid sequence and size, but also in their substrate specificities and catalytic activities, and therefore, it is quite difficult to estimate their reactivity . We have developed an NMR-based method using the enzymatic labeling technique (ELT) for simultaneous analysis of the substrate specificities and reaction rates of TGases . It is quite useful for comparing the existing TGases and for screening new TGases or TGases variants . This method has shown that MTG is superior for industrial use because of its lower substrate specificity compared with those of guinea pig liver transglutaminase (GTG) and red sea bream liver transglutaminase (FTG) . We have also found that an MTG variant lacking an N-terminal aspartic acid residue has higher activity than that of the native enzyme.

J AOAC Int, 2002 Jan-Feb, 85(1), 15 - 9
Liquid chromatographic determination of amphotericin B in different pharmaceuticals; Lue LP et al.; Amphotericin B (AmB) is one of the most potent antifungal agents and the drug of choice in the treatment of serious fungal infections . A liquid chromatographic (LC) method was developed to determine AmB in pharmaceutical formulations for injection, tissue culture, cream, and lotion . pBondapak C18 reversed-phase column and a simple mobile phase consisting of acetonitrile-water-acetic acid (40 + 54 + 6, v/v) was used . The flow rate was 1.8 mL/min and the effluent was monitored at 405 nm . The developed LC method uses piroxicam as an internal standard and has a limit of detection of 10 ng/mL, a limit of quantitation of 30 ng/mL, and the assay is linear from 0.01 to 100 microg/mL . AmB and piroxicam elute with retention times of 12.4 and 4.0 min, respectively, and the resolution between AmB and piroxicam was 10.6 . In comparison with the official United States Pharmacopeia microbial assay for AmB, this LC method is more rapid, selective, sensitive, and offers positive identification.

Environ Toxicol Chem, 2002 Mar, 21(3), 640 - 7
Investigation of effects of trifluoroacetate on vernal pool ecosystems; Benesch JA et al.; Trifluoroacetate (CH3COO-, TFA) is a breakdown product of hydrochlorofluorocarbons and hydrofluorocarbons and is released by the heating of Teflon products . Because of its chemical properties, concentrations in evaporative wetlands are predicted to increase with time . This study focused on assessing the impact of this haloacetic acid on vernal pool soil microbial communities as well as vernal pool and wetland plant species . Microbial respiration for three vernal pool soils and an agricultural soil was not affected by TFA exposures (0, 10, 100, 1,000, and 10,000 microg/L), and degradation of TFA by microbial communities was not observed in soils incubated for three months . Trifluoroacetate accumulated in foliar tissue of wetland plant species as a function of root exposure concentration (100 and 1,000 microg/L TFA), and accumulation was found to stabilize or decrease after the second or third month of exposure . Seeds accumulated TFA as a function of root exposure concentration; however, germination success was not affected . No adverse physiological responses, including general plant health and photosynthetic and conductance rates, were observed for root exposures at the TFA concentrations used in this study . Based on the soils and plant species used in this study, predicted TFA concentrations will not adversely affect the development of soil microbial communities and vernal pool plant species.

Therapie, 2001 Nov-Dec, 56(6), 653 - 61
{Septic shock and selenium administration}; Forceville X et al.; Selenium is an essential trace element . In the form of selenocysteine, an amino acid, selenium is necessary for the activity of important enzymes (i.e . glutathione peroxidases, thioredoxin reductase) . In the periodic table of the elements, selenium belongs to the same column as oxygen . In fact, seleno-enzymes have an important role in the detoxification of reactive oxygen species, especially peroxides and hydroperoxides . In septic and septic-like shock patients, reactive oxygen species, particularly peroxides, play an important role through their destructive actions, which are favourable as critical components of microbial destruction and also deleterious in excessive generation . This excessive generation results in tissue damage . Moreover, reactive oxygen species modulate the activation of important intracellular mediators (NF kappa B activation, arachidonic acid cascade) . Simultaneously in patients with severe infection, there is a marked and early plasma selenium decrease . Redistribution due to selective selenium uptake for metabolic use could be one of the main mechanisms for this decrease . This review was carried out by questioning on the one hand the Medline database, by consulting the reviews and works available in the services of biology, biochemistry and pharmacy, by a prospective follow-up on the subject in Current Contents, but also thanks to library searches carried out by Aguettant laboratories . Several supplementary studies at various doses (from 140 to 1000 micrograms/day sodium selenite) have been conducted, though only on small groups of patients and with a questionable design . Selenium treatment seem to be promising in severely septic patients . However, in the absence of pertinent clinical data, only the administration of doses below adverse effect levels, staying within physiological limits, can presently be recommended (i.e . 200 to 500 micrograms/day of sodium selenite).

Semin Oncol Nurs, 2002 Feb, 18(1), 44 - 9
Dietary recommendations for neutropenic patients; Wilson BJ; OBJECTIVES: To describe the development of an evidence-based practice project that will evaluate less restrictive dietary practices and focus on hand washing in adult patients with chemotherapy-induced neutropenia . DATA SOURCES: Guidelines, protocols, and published articles . CONCLUSIONS: There is a lack of scientific basis for food restrictions, a wide variation in policies related to low-microbial diets, and inconsistent compliance with restricted diets . Furthermore, lack of consistent practice has not been related to incidence of infection . IMPLICATIONS FOR NURSING PRACTICE: Evaluation of an evidence-based project such as this can lead to change in practice and institutional policy.

J Exp Med, 2002 Mar 4, 195(5), 625 - 36
Functionally distinct subsets of CD1d-restricted natural killer T cells revealed by CD1d tetramer staining; Gumperz JE et al.; CD1d-restricted natural killer (NK)T cells are known to potently secrete T helper (Th)1 and Th2 cytokines and to mediate cytolysis, but it is unclear how these contrasting functional activities are regulated . Using lipid antigen-loaded CD1d tetramers, we have distinguished two subsets of CD1d-restricted T cells in fresh peripheral blood that differ in cytokine production and cytotoxic activation . One subset, which was CD4(-), selectively produced the Th1 cytokines interferon gamma and tumor necrosis factor alpha, and expressed NKG2d, a marker associated with cytolysis of microbially infected and neoplastic cells . This subset up-regulated perforin after exposure to interleukin (IL)-2 or IL-12 . In contrast, CD4(+) CD1d-restricted NKT cells potently produced both Th1 and Th2 cytokines, up-regulated perforin in response to stimulation by phorbol myristate acetate and ionomycin but not IL-2 or IL-12, and could be induced to express CD95L . Further, for both CD1d-restricted NKT cell subsets, we found that antigenic stimulation induced cytokine production but not perforin expression, whereas exposure to inflammatory factors enhanced perforin expression but did not stimulate cytokine production . These results show that the various activities of CD1d-restricted T cells in tumor rejection, autoimmune disease, and microbial infections could result from activation of functionally distinct subsets, and that inflammatory and antigenic stimuli may influence different effector functions.

Microbiol Mol Biol Rev, 2002 Mar, 66(1), 64 - 93; table of contents
Alpha-crystallin-type heat shock proteins: socializing minichaperones in the context of a multichaperone network; Narberhaus F; Alpha-crystallins were originally recognized as proteins contributing to the transparency of the mammalian eye lens . Subsequently, they have been found in many, but not all, members of the Archaea, Bacteria, and Eucarya . Most members of the diverse alpha-crystallin family have four common structural and functional features: (i) a small monomeric molecular mass between 12 and 43 kDa; (ii) the formation of large oligomeric complexes; (iii) the presence of a moderately conserved central region, the so-called alpha-crystallin domain; and (iv) molecular chaperone activity . Since alpha-crystallins are induced by a temperature upshift in many organisms, they are often referred to as small heat shock proteins (sHsps) or, more accurately, alpha-Hsps . Alpha-crystallins are integrated into a highly flexible and synergistic multichaperone network evolved to secure protein quality control in the cell . Their chaperone activity is limited to the binding of unfolding intermediates in order to protect them from irreversible aggregation . Productive release and refolding of captured proteins into the native state requires close cooperation with other cellular chaperones . In addition, alpha-Hsps seem to play an important role in membrane stabilization . The review compiles information on the abundance, sequence conservation, regulation, structure, and function of alpha-Hsps with an emphasis on the microbial members of this chaperone family.

J Vet Pharmacol Ther, 2002 Feb, 25(1), 25 - 32
Serum pharmacokinetics and tissue and milk residues of oxytetracycline in goats following a single intramuscular injection of a long-acting preparation and milk residues following a single subcutaneous injection; Payne MA et al.; Separate groups of goats were used to determine drug depletion patterns in serum (n=10), tissue (n=20) and milk (n=8) following a single intramuscular (i.m.) dose of 20 mg/kg of a long-acting oxytetracycline (OTC) formulation (Liquamycin LA-200) . Milk residues were also determined following a subcutaneous (s.c.) administration of the same product at the same dose . Serum samples were taken for 24 h post-treatment and tissues (fat, liver, kidney, muscle and injection site) collected at 4, 7, 14, 21 and 28 days following injection . Milk from lactating goats was collected every 12 h for 8 days following both the i.m . and s.c . treatments utilizing an intervening 5-week washout period . Residues in serum and tissue were measured using a microbial inhibition assay, while milk residues were measured using both a microbial inhibition assay and a validated HPLC method . The serum pharmacokinetic parameters of OTC in goats were determined, with a mean AUC=67.4 microg h/mL, mean terminal half-life=14.4 h, and apparent clearance=0.33 L/kg h . Tissue half-lives could not be determined with confidence because the collection times provided only two points at which residues could be measured for most tissues . Oxytetracycline residues in all goat tissue samples measured less then cattle tissue tolerance by 96 h postdosing . One-compartment model describing milk depletion data for i.m . and s.c . dosing had terminal slope half-lives of 20.1 and 36.1 h, respectively . By 96 h post-treatment none of the milk samples contained OTC residues in excess of the cattle milk tolerance (0.3 p.p.m.) . For both milk and tissue, the upper-bound 99% confidence intervals for the samples taken from goats 96 h postdosing were lower than approved cow milk and tissue tolerances.

J Bacteriol, 2002 Mar, 184(6), 1806 - 10
Protective role of tolC in efflux of the electron shuttle anthraquinone-2,6-disulfonate; Shyu JB et al.; Extracellular electron transfer can play an important role in microbial respiration on insoluble minerals . The humic acid analog anthraquinone-2,6-disulfonate (AQDS) is commonly used as an electron shuttle during studies of extracellular electron transfer . Here we provide genetic evidence that AQDS enters Shewanella oneidensis strain MR-1 and causes cell death if it accumulates past a critical concentration . A tolC homolog protects the cell from toxicity by mediating the efflux of AQDS . Electron transfer to AQDS appears to be independent of the tolC pathway, however, and requires the outer membrane protein encoded by mtrB . We suggest that there may be structural and functional relationships between quinone-containing electron shuttles and antibiotics.

Appl Environ Microbiol, 2002 Mar, 68(3), 1446 - 53
Identification of the functionally active methanotroph population in a peat soil microcosm by stable-isotope probing; Morris SA et al.; The active population of low-affinity methanotrophs in a peat soil microcosm was characterized by stable-isotope probing . "Heavy" (13)C-labeled DNA, produced after microbial growth on (13)CH(4), was separated from naturally abundant (12)C-DNA by cesium chloride density gradient centrifugation and used as a template for the PCR . Amplification products of 16S rRNA genes and pmoA, mxaF, and mmoX, which encode key enzymes in the CH(4) oxidation pathway, were analyzed . Sequences related to extant type I and type II methanotrophs were identified, indicating that these methanotrophs were active in peat exposed to 8% (vol/vol) CH(4) . The (13)C-DNA libraries also contained clones that were related to beta-subclass Proteobacteria, suggesting that novel groups of bacteria may also be involved in CH(4) cycling in this soil.

Appl Environ Microbiol, 2002 Mar, 68(3), 1425 - 30
Quantitative detection of microbial genes by using DNA microarrays; Cho JC et al.; To quantify target genes in biological samples using DNA microarrays, we employed reference DNA to normalize variations in spot size and hybridization . This method was tested using nitrate reductase (nirS), naphthalene dioxygenase (nahA), and Escherichia coli O157 O-antigen biosynthesis genes as model genes and lambda DNA as the reference DNA . We observed a good linearity between the log signal ratio and log DNA concentration ratio at DNA concentrations above the method's detection limit, which was approximately 10 pg . This approach for designing quantitative microarrays and the inferred equation from this study provide a simple and convenient way to estimate the target gene concentration from the hybridization signal ratio.

J Biochem (Tokyo), 2002 Mar, 131(3), 399 - 405
Employment of the human estrogen receptor beta ligand-binding domain and co-activator SRC1 nuclear receptor-binding domain for the construction of a yeast two-hybrid detection system for endocrine disrupters; Lee HS et al.; To screen a wide variety of chemicals for endocrine disrupters, and to develop an effective microbial degradation system for them, a good system is needed for the rapid and accurate evaluation of the endocrine-disrupting activities of suspected chemicals and their degradation products . We constructed two-hybrid systems that co-express the Gal4p DNA binding domain/ligand-binding domain of human estrogen receptor (hER) alpha or beta and the Gal4p transactivation domain/nuclear receptor-binding domain of co-activator SRC1, TIF2, or AIB1 in Saccharomyces cerevisiae with a chromosome-integrated lacZ reporter gene under the control of Gal4p-binding sites . We found that the combination of the hERbeta ligand-binding domain and SRC1 nuclear receptor-binding domain was most effective for the xenoestrogen-dependent induction of reporter activity . The extent of transcriptional activation by known xenoestrogens and phytoestrogens was found to correlate well with their estrogenic activities as measured by the previous system with rat ERalpha . This system detects estrogenic activity in some chemicals that have not been suspected of being positive . We also applied this assay system to test the microbial degradation products of gamma-hexachlorocyclohexane (gamma-HCH) by Sphingomonas paucimobilis . Among the gamma-HCH metabolites, 2,5-dichlorohydroquinone and chlorohydroquinone had estrogenic activities similar to the original chemical, while hydroquinone, a later stage metabolite, showed no activity, suggesting the necessity of evaluating intermediate metabolites in microbial degradation systems.

Lancet Infect Dis, 2001 Dec, 1(5), 345 - 53
Hot spots in a wired world: WHO surveillance of emerging and re-emerging infectious diseases; Heymann DL et al.; The resurgence of the microbial threat, rooted in several recent trends, has increased the vulnerability of all nations to the risk of infectious diseases, whether newly emerging, well-established, or deliberately caused . Infectious disease intelligence, gleaned through sensitive surveillance, is the best defence . The epidemiological and laboratory techniques needed to detect, investigate, and contain a deliberate outbreak are the same as those used for natural outbreaks . In April 2000, WHO formalised an infrastructure (the Global Outbreak Alert and Response Network) for responding to the heightened need for early awareness of outbreaks and preparedness to respond . The Network, which unites 110 existing networks, is supported by several new mechanisms and a computer-driven tool for real time gathering of disease intelligence . The procedure for outbreak alert and response has four phases: systematic detection, outbreak verification, real time alerts, and rapid response . For response, the framework uses different strategies for combating known risks and unexpected events, and for improving both global and national preparedness . New forces at work in an electronically interconnected world are beginning to break down the traditional reluctance of countries to report outbreaks due to fear of the negative impact on trade and tourism . About 65% of the world's first news about infectious disease events now comes from informal sources, including press reports and the internet.

J Environ Monit, 2002 Feb, 4(1), 55 - 69
A brief overview of modern directions in marine DOC studies part II--recent progress in marine DOC studies; Dafne- EV et al.; Progress made in analytical techniques allows the formulation of new concepts in the biogeochemistry of organic carbon . The second part of our review summarizes the latest evolution and introduces new ideas in the biogeochemistry of marine dissolved organic carbon (DOC) . Via classification of different fractions and sources of DOC, characterization of its composition, age and availability for bacterial utilization, and fate of DOC, we show the role of DOC in the global carbon cycle and the significance of bulk DOC in the oceans . Special emphasis is placed on the microbial loop in the cycling of DOC and its relation with higher trophic levels (phytoplankton and zooplankton) . Significant progress has also been made in the study of the roles of colloidal organic material in metal complexation, ultraviolet radiation in dissolved organic matter photochemical oxidation, and chromophore-containing constituents of DOC as the signature of DOC for satellite observations . The importance of bulk DOC in the global carbon cycle requires the inclusion of this fraction in the regional and global carbon models . We predict that future DOC study in the ocean will focus on the development of sophisticated, almost continuously recording, moored DOC instrument arrays for the monitoring of small-scale DOC horizontal and vertical patchiness; widespread time series stations including estuarine, coastal and open environments; more detailed chemical characterization of different fractions of organic carbon from diverse marine habitats; parameterization of predictive models of DOC cycling on regional and global scales, incorporating the microbial loop; and finally, monitoring of DOC dynamics from satellites on regional and global scales.

J Environ Monit, 2002 Feb, 4(1), 35 - 42
Total organic carbon analysis as a precursor to disinfection byproducts in potable water: oxidation technique considerations; Wallace B et al.; In recent years, an increasing number of regulations and methodologies have begun to utilize total organic carbon (TOC) analysis for monitoring microbial contamination and/or disinfectant byproduct (DBP) precursors . This paper highlights some analytical differences and similarities between the two widely used TOC oxidation techniques: UV persulfate and high temperature combustion (HTC) . Previous papers have come to different and sometimes contradictory conclusions on this subject . However, these studies either compared instruments with significantly different flow paths or TOC systems from different eras . Unlike previous studies, this paper compares two modern TOC analyzers with nearly identical flow paths for sample recovery, detection limits, and analysis of real world samples . On average, both persulfate and HTC oxidation yielded good recoveries for 10 hard to oxidize compounds and potable water samples from 5 different locations across the USA . In general, persulfate yielded more precise results because of its lower background response relative to sample response while HTC gave slightly higher results (roughly 2% to 3%) for surface water samples.

Environ Sci Technol, 2002 Feb 1, 36(3), 512 - 9
Iron oxide surface-catalyzed oxidation of ferrous iron by monochloramine: implications of oxide type and carbonate on reactivity; Vikesland PJ et al.; The maintenance of monochloramine residuals in drinking water distribution systems is one technique often used to minimize microbial outbreaks and thereby maintain the safety of the water . Reactions between oxidizable species and monochloramine can however lead to undesirable losses in the disinfectant residual . Previous work has illustrated that the Fe(II) present within distribution systems is one type of oxidizable species that can exert a monochloramine demand . This paper extends this prior work by examining the kinetics of the reactions between Fe(II) and monochloramine in the presence of a variety of iron oxide surfaces . The identity of the iron oxide plays a significant role in the rate of these reactions . Surface area-normalized initial rate coefficients (k(init)) obtained in the presence of each oxide at pH approximately 6.9 exhibit the following trend in catalytic activity: magnetite > goethite > hematite approximately = lepidocrocite > ferrihydrite . The differences in the activity of these oxides are hypothesized to result from variations in the amount of Fe(II) sorbed to each of the oxides and to dissimilarities in the surface site densities of the oxides . The implications of carbonate on Fe(II) sorption to iron oxides are also examined . Comparing Fe(II) sorption isotherms for goethite obtained under differential carbonate concentrations, it is apparent that as the carbonate concentration (C(T,CO3)) increased from 0 to 11.7 mM that the Fe(II) sorption edge (50% sorption) shifts from a pH of approximately 5.8 to a pH of 7.8 . This shift is hypothesized to be the result of the formation of aqueous and surface carbonate-Fe(II) complexes and to competition between carbonate and Fe(II) for surface sites . The implications of these changes are then discussed in light of the variable oxide studies.

Hum Reprod, 2002 Mar, 17(3), 726 - 35
Seminal antibodies to human 60kd heat shock protein (HSP 60) in male partners of subfertile couples; Eggert-Kruse W et al.; BACKGROUND: Heat shock proteins (HSP) are essential mammalian and bacterial stress proteins . At the cellular level, they act as chaperones, have important regulatory functions, and are considered to be an essential factor for reproduction . Scarce information exists on the role of sensitization to HSP and the potential role in the aetiology of male infertility . METHODS: The potential association of immunoglobulin (Ig)A antibodies (Ab) to the human 60 kDa heat shock protein (HSP 60) with several parameters of subclinical male genital tract infection/inflammation and with semen quality and sperm fertilizing capacity was analysed in a prospective study . IgA Ab to human HSP 60 were determined in seminal plasma of 202 randomly chosen male partners of subfertile couples with a median duration of infertility of 4 years (range 1-15 years), who were asymptomatic for genital tract infection . After medical history and clinical examination, a comprehensive evaluation of semen quality, in aliquots of the same ejaculates used for HSP Ab determination, included: sperm analysis; local antisperm antibody (ASA) screening; standardized sperm-cervical mucus (CM) penetration testing; immunocytochemical round cell differentiation to determine seminal leukocyte counts; evaluation of complement fraction C(3) and of some pro-inflammatory cytokines; and microbial screening . Subsequent fertility was recorded after 6 months . RESULTS: The presence of HSP 60 IgA Ab in seminal fluid (total positive 6.9%) was significantly associated with leukocytospermia, the presence of C(3), and also with high interleukin (IL) levels in seminal plasma . HSP 60 Ab were not related to the bacterial colonization of ejaculates . There was no association of seminal IgA Ab to human HSP 60 with semen quality, determined with microscopical semen analysis, nor with local IgG- or IgA-class ASA . There was no relationship with sperm intrinsic motility and duration of motility in the sperm CM-penetration test, nor with sperm fertilizing capacity . CONCLUSIONS: The combined presence of IgA Ab to human 60 kDa HSP, leukocytes and other established infection/inflammation markers in semen might suggest a potential role of the immune response to heat shock proteins (HSP) in cases of silent male genital tract infection, but the results do not indicate a marked relationship of HSP 60 Ab in seminal fluid with standard parameters of semen quality.

J Microbiol Methods, 2002 May, 49(3), 315 - 9
Long PCR-amplified rDNA for PCR-RFLP- and Rep-PCR-based approaches to recognize closely related microbial species; Abd-El-Haleem D et al.; Long PCR was used to amplify a 5-kb fragment of the bacterial ribosomal operon (16S-intergenic spacer region (ISR)-23S) from several Ralstonia eutropha strains (16S rDNA sequence similarity: 97-99%) . Due to the large product size, amplicons from the different strains could be distinguished using restriction enzyme fragment length polymorphisms (RFLP) and repetitive PCR analysis (Rep-PCR) with the primer 1492r . These methods may prove useful in differentiating other bacterial strains with highly similar 16S rDNA sequences.

J Microbiol Methods, 2002 May, 49(3), 301 - 6
Microbial identification by immunohybridization assay of artificial RNA labels; Kourentzi KD et al.; Ribosomal RNA (rRNA) and engineered stable artificial RNAs (aRNAs) are frequently used to monitor bacteria in complex ecosystems . In this work, we describe a solid-phase immunocapture hybridization assay that can be used with low molecular weight RNA targets . A biotinylated DNA probe is efficiently hybridized in solution with the target RNA, and the DNA-RNA hybrids are captured on streptavidin-coated plates and quantified using a DNA-RNA heteroduplex-specific antibody conjugated to alkaline phosphatase . The assay was shown to be specific for both 5S rRNA and low molecular weight (LMW) artificial RNAs and highly sensitive, allowing detection of as little as 5.2 ng (0.15 pmol) in the case of 5S rRNA . Target RNAs were readily detected even in the presence of excess nontarget RNA . Detection using DNA probes as small as 17 bases targeting a repetitive artificial RNA sequence in an engineered RNA was more efficient than the detection of a unique sequence.

J Microbiol Methods, 2002 May, 49(3), 275 - 84
Bacterial genomics: the use of DNA microarrays and bacterial artificial chromosomes; Ball KD et al.; Immense amounts of genetic information are contained within microbial genomes . As the number of completely sequenced microbial genomes is increasing, functional and comparative genomic techniques will be employed for sequence analysis and gene characterization . Sequence comparison and expression profiling by DNA microarrays can determine phylogenetic relationships and identify genes while bacterial artificial chromosomes (BACs) allow the study of entire biochemical pathways and permit the expression of bacterial genes in a foreign host.

Proc Natl Acad Sci U S A, 2002 Mar 5, 99(5), 3135 - 40 Epub 2002 Feb 26.
Dynamics of bacterial phenotype selection in a colonized host; Webb GF et al.; The population dynamics of Helicobacter pylori during colonization in an infected animal host provide a quantifiable experimental model of in vivo microbial phenotype evolution . Phenotype variability in H . pylori populations can be typed as polymorphic expression of Lewis antigens on their cell surfaces . The high mutational frequency of H . pylori for Lewis expression provides substrate for differential selection by the host . Experimental challenge and successful colonization of mice and gerbils allows tracking of H . pylori phenotype variability from the initial inoculation to the ultimate establishment of a quasispecies . Colonization data provide a quantitative experimental model of phenotype evolution in a relatively large population (>10(4) individuals) over a relatively long evolutionary time scale (>10(3) generations) . A mathematical model is developed to interpret the data in terms of the dynamic processes occurring during colonization . The mathematical model distinguishes the roles of selection and mutation; quantifies the effects of initial phenotype diversity, mutational frequency, and selective advantage; and applies generally to phenotype evolution in biological populations.

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