Trends Microbiol, 2004 Jul, 12(7), 325 - 36 Strategies of the home-team: symbioses exploited for vector-borne disease control; Rio RV et al.; Symbioses between eukaryotes and unicellular organisms are quite common, with examples copiously disseminated throughout the earth's biota . Arthropods, in particular, owe much of their ecological success to their microbial flora, which often provide supplements either lacking in the limited host diet or which the hosts are unable to synthesize . In addition to harboring beneficial microbes, many arthropods (vectors) also transmit pathogens to the animals and plants upon which they prey . Vector-borne diseases exact a high public health burden and additionally have a devastating impact on livestock and agriculture . Recent scientific discoveries have resulted in the development of powerful technologies for studying the vector's biology, to discover the weak links in disease transmission . One of the more challenging applications of these developments is transgenesis, which allows for insertion of foreign DNA into the insect's genome to modify its phenotype . In this review, we discuss an approach in which the naturally occurring commensal flora of insects are manipulated to express products that render their host environment inhospitable for pathogen transmission . Replacing susceptible insect genotypes with modified counterparts with reduced pathogen transmission ability, might provide a new set of armaments in the battle for vector-borne disease reduction. Mol Immunol, 2004 Jul, 41(6-7), 577 - 82 The expanding family of MyD88-like adaptors in Toll-like receptor signal transduction; McGettrick AF et al.; Toll-like receptors (TLRs) play an essential role in the detection and elimination of invading microbes . They are type-1 transmembrane receptors, containing extracellular leucine rich repeats and an intracellular Toll/interleukin-1 receptor (TIR) domain . Upon stimulation, these receptors interact with specific TIR domain-containing adaptor proteins . Five such adaptors have been discovered to date, MyD88, Mal (MyD88 adaptor-like)/TIRAP (TIR domain-containing adaptor protein), Trif (TIR-domain-containing adaptor inducing interferon-beta), TRAM (Trif-related adaptor molecule) and SARM (SAM and ARM-containing protein) . Different TLRs use different combinations of these adaptors, leading to the activation of common and unique pathways involved in the elimination of the invading microbe. Cell Struct Funct, 1999 Oct, 24(5), 405 - 12 Biophysical properties of stable microtubules in neurites revealed by optical techniques; Kurachi M et al.; We tested the stability of microtubules in the neurites of cultured dorsal root ganglion cells by dissolving the cytoplasmic membrane with detergent and exposing them to defined extracellular medium under the microscope . Smooth cytoplasmic filaments visualized after membrane removal were suggested to be microtubules by the preservation of all of the filaments in the presence but not in the absence of taxol . They were further confirmed to be microtubules by immunostaining with anti-tubulin antibody . Significant number of microtubules in the established neurites remained longer than 1 hour after membrane removal . To investigate their stabilization mechanism, we transected the exposed microtubules by laser microbeam irradiation and observed their length changes with video-enhanced microscopy . Microtubule fragments started to shorten on both sides of the transection site, more rapidly from the newly generated plus ends than from the minus ends . The maximal rate as well as the pattern of shortening correlated with the time of transection; microtubules transected later than 30 min after membrane removal shortened at rates less than 20 microm/min and typically with intermittent pauses, while the more labile microtubules included in the earlier transections shortened continuously at higher rates . Microtubules in neurites were thus stabilized by (1) stopping disassembly at local sites including the plus ends, and (2) slowing disassembly along the length . Observations of the course of disassembly also suggested the presence of specialized points along microtubules which is involved in anchoring microtubules to the substratum or transiently stopping disassembly. Ann Surg, 2004 Jul, 240(1), 132 - 41 Bone marrow norepinephrine mediates development of functionally different macrophages after thermal injury and sepsis; Cohen MJ et al.; OBJECTIVE: We sought to determine the influence of thermal (burn) injury with sepsis and norepinephrine on the clonogenic potential and functional cytokine response to lipopolysaccharide (LPS) stimulation in nonmyeloid committed (CD117) and myeloid committed (ER-MP12) bone marrow progenitor cells . SUMMARY AND BACKGROUND DATA: We have previously demonstrated that norepinephrine stimulated myelopoiesis after burn injury and sepsis, but the site of this stimulation in monocyte development is unknown . In the present study the influence of norepinephrine on the developmental hierarchy of bone marrow cells after thermal injury and sepsis was determined by assessing the clonogenic potential and LPS-stimulated cytokine responses of mature macrophages derived from CD117 and ER-MP12 bone marrow progenitor cells . METHODS: Tissue and bone marrow norepinephrine content was ablated by chemical sympathectomy with 6-hydroxydopamine treatment . CD117 and ER-MP12 bone marrow cells were isolated using antibody-linked magnetic microbeads . Clonogenic potential in response to colony-stimulating factors was determined . Both progenitor cell types were differentiated to mature macrophages in vitro and tumor necrosis factor (TNF)-alpha and interleukin (IL)-6 cytokine responses to LPS provocation were determined . RESULTS: The macrophage- and granulocyte-macrophage colony-stimulating factor responsive clonogenic potential was increased with burn sepsis, suggesting an expansion of both progenitor populations . Such increases were greatly reduced with prior depletion of norepinephrine . TNF-alpha and IL-6 cytokine responses to LPS were markedly influenced by the specific progenitor cells involved as well as the injury conditions and the status of norepinephrine prior to injury . In burn sepsis the depletion of norepinephrine resulted in a dramatic decrease in both IL-6 and TNF-alpha production by both progenitor-derived macrophages . CONCLUSIONS: Depletion of norepinephrine attenuated burn and burn sepsis-induced bone marrow progenitor clonal growth in response to macrophage- and granulocyte-macrophage colony-stimulating factor . Functional phenotypes of bone marrow progenitor-derived macrophages are greatly influenced by norepinephrine and the milieu created by thermal injury and sepsis. Fish Shellfish Immunol, 2004 Aug, 17(2), 121 - 8 Identification of genes involved in the response of haemocytes of Penaeus japonicus by suppression subtractive hybridization (SSH) following microbial challenge; He N et al.; Penaeus japonicus were injected with a heat-killed microorganism suspension and 291 randomly selected cDNA fragments generated by suppression subtractive hybridization (SSH) were sequenced . A total of 71 cDNA clones corresponding to 25 genes were found to have enhanced expression, of which eight are found for the first time in shrimp . The most abundant gene in the subtractive library was Kunitz-type protease inhibitor, clearly indicating this protease inhibitor in the response . A number of genes encoding signaling molecules, such as Ras-related nuclear protein (Ran), growth factor receptor bound protein (Grb), TGF-beta receptor interacting protein, integrin binding protein and interferon receptor bound protein were found for the first time in the shrimp, and they may be involved in the regulation of the host defense against the injected microbes . Furthermore, cDNAs of chaperonin, proteasome, antioxidant as well as genes associated with actin reorganization, which may be necessary for phagocytosis and encapsulation, were also expressed at a higher level after the challenge . These results may facilitate the understanding of shrimp immune responses. J Oral Rehabil, 2004 Jul, 31(7), 647 - 52 A 5-year follow-up study on the prosthetic rehabilitation of the elderly in Helsinki, Finland; Nevalainen MJ et al.; In 1990, 364 elderly (76-86 years) inhabitants of Helsinki, Finland, attended a dental and oral examination study that was conducted as part of the Helsinki Aging Study . In spring 1996, these subjects were recalled for a 5-year follow-up . Between the baseline and follow-up examinations, 114 (31%) subjects had deceased (86 women and 28 men), whereas 134 had either moved, were too ill, or refused to participate in the follow-up . Follow-up examination was conducted for 113 subjects (79 women and 34 men), with the participating rate being 46% . Five subjects became edentulous during the follow-up . Of the subjects, 61% had 1-32 teeth at follow-up . In these subjects, the mean number of teeth decreased from 14.9 (+/-8.3) to 13.5 (+/-8.6) (P < 0.0001) . Prosthetic status changed in 40% of the elderly dentate people: 25% received new prostheses whereas 15% lost prostheses that were not replaced . New fixed partial dentures were made in five maxillae and in nine mandibles during the follow-up . Acrylic removable partial dentures (ARPD) were most frequently used: 35% of dentate subjects had an ARPD . Subjects with removable prostheses had higher levels of salivary microbes and higher root caries incidence than those with natural teeth . Furthermore, the presence of removable prostheses at baseline, together with the male gender, was clearly associated with tooth loss during follow-up . This study indicates that fixed rather than removable prostheses should be used in elderly patients . The need for a removable denture ought to be carefully considered. Notes Rec R Soc Lond, 2004 May, 58(2), 187 - 201 The discovery of microorganisms by Robert Hooke and Antoni Van Leeuwenhoek, fellows of the Royal Society; Gest H; The existence of microscopic organisms was discovered during the period 1665-83 by two Fellows of The Royal Society, Robert Hooke and Antoni van Leeuwenhoek . In Micrographia (1665), Hooke presented the first published depiction of a microganism, the microfungus Mucor . Later, Leeuwenhoek observed and described microscopic protozoa and bacteria . These important revelations were made possible by the ingenuity of Hooke and Leeuwenhoek in fabricating and using simple microscopes that magnified objects from about 25-fold to 250-fold . After a lapse of more than 150 years, microscopy became the backbone of our understanding of the roles of microbes in the causation of infectious diseases and the recycling of chemical elements in the biosphere. Res Microbiol, 2004 Jun, 155(5), 352 - 9 Adaptive mutation and amplification in Escherichia coli: two pathways of genome adaptation under stress; Hersh MN et al.; The neo-Darwinists suggested that evolution is constant and gradual, and thus that genetic changes that drive evolution should be too . However, more recent understanding of phenomena called adaptive mutation in microbes indicates that mutation rates can be elevated in response to stress, producing beneficial and other mutations . We review evidence that, in Escherichia coli, two separate mechanisms of stress-induced genetic change occur that revert a lac frameshift allele allowing growth on lactose medium . First, compensatory frameshift ("point") mutations occur by a mechanism that includes DNA double-strand breaks and (we have suggested) their error-prone repair . Point mutation requires induction of the RpoS-dependent general stress response, and the SOS DNA damage response leading to upregulation of the error-prone DNA polymerase DinB (Pol IV), and occurs during a transient limitation of post-replicative mismatch repair activity . A second mechanism, adaptive amplification, entails amplification of the leaky lac allele to 20-50 tandem repeats . These provide sufficient beta-galactosidase activity for growth, thereby apparently deflecting cells from the point mutation pathway . Unlike point mutation, amplification neither occurs in hypermutating cells nor requires SOS or DinB, but like point mutation, amplification requires the RpoS-dependent stress response . Similar processes are being found in other bacterial systems and yeast . Stress-induced genetic changes may underlie much of microbial evolution, pathogenesis and antibiotic resistance, and also cancer formation, progression and drug resistance. Science, 2004 Jul 23, 305(5683), 509 - 13 Epub 2004 Jun 17. Ecosystem properties and forest decline in contrasting long-term chronosequences; Wardle DA et al.; During succession, ecosystem development occurs; but in the long-term absence of catastrophic disturbance, a decline phase eventually follows . We studied six long-term chronosequences, in Australia, Sweden, Alaska, Hawaii, and New Zealand; for each, the decline phase was associated with a reduction in tree basal area and an increase in the substrate nitrogen-to-phosphorus ratio, indicating increasing phosphorus limitation over time . These changes were often associated with reductions in litter decomposition rates, phosphorus release from litter, and biomass and activity of decomposer microbes . Our findings suggest that the maximal biomass phase reached during succession cannot be maintained in the long-term absence of major disturbance, and that similar patterns of decline occur in forested ecosystems spanning the tropical, temperate, and boreal zones. Inhal Toxicol, 2004 Jul, 16(8), 509 - 15 The alteration of immune reactions in inbred BALB/c mice following low-level sarin inhalation exposure; Kassa J et al.; To study the influence of low-level sarin inhalation exposure on immune functions, inbred BALB/c mice were exposed to low concentrations of sarin for 60 min in the inhalation chamber . The evaluation of immune functions was carried out using phenotyping of CD3 (T lymphocytes), CD4 (helper T lymphocytes), CD8 (cytotoxic T lymphocytes), and CD19 cells (B lymphocytes) in the lungs, blood, and spleen, lymphoproliferation of spleen cells stimulated in vitro by various mitogens (concanavalin A, lipopolysaccharides), phagocyte activity of peritoneal and alveolar macrophages, production of N-oxides by peritoneal macrophages, and the measurement of the natural killer cell activity at 1 wk following sarin exposure . The results were compared to the values obtained from control mice exposed to pure air instead of sarin . The results indicate that low doses of sarin are able to alter the reaction of immune system at one week following exposure to sarin . While the numbers of CD3 cells in the lungs, blood, and spleen were slightly decreased, an increase in CD19 cells was observed, especially in the lungs and blood . The reduced proportion of T lymphocytes is caused by decay of CD4-positive T cells . Lymphoproliferation was significantly decreased regardless of the mitogen and sarin concentration used . The production of N-oxides by peritoneal macrophages was stimulated after exposure to the highest dose of sarin, whereas their ability to phagocytize the microbes was increased after exposure to the lowest dose of sarin . The natural killer cell activity was significantly higher in the case of inhalation exposure of mice to the highest level of sarin . Thus, not only organophosphorus insecticides but also nerve agents such as sarin are able to alter immune functions even at a dose that does not cause clinically manifested disruption of cholinergic nervous system in the case of inhalation exposure . Nevertheless, the alteration of immune functions following the inhalation exposure to a symptomatic concentration of sarin seems to be more pronounced. Immunol Rev, 2004 Apr, 198, 106 - 15 A Toll-like receptor in horseshoe crabs; Inamori K et al.; Non-self-recognition of invading microbes relies on the pattern-recognition of pathogen-associated molecular patterns (PAMPs) derived from microbial cell-wall components . Insects and mammals conserve a signaling pathway of the innate immune system through cell-surface receptors called Tolls and Toll-like receptors (TLRs) . Bacterial lipopolysaccharides (LPSs) are an important trigger of the horseshoe crab's innate immunity to infectious microorganisms . Horseshoe crabs' granular hemocytes respond specifically to LPS stimulation, inducing the secretion of various defense molecules from the granular hemocytes . Here, we show a cDNA which we named tToll, coding for a TLR identified from hemocytes of the horseshoe crab Tachypleus tridentatus . tToll is most closely related to Drosophila Toll in both domain architecture and overall length . Human TLRs have been suggested to contain numerous PAMP-binding insertions located in the leucine-rich repeats (LRRs) of their ectodomains . However, the LRRs of tToll contained no obvious PAMP-binding insertions . Furthermore, tToll was non-specifically expressed in horseshoe crab tissues . These observations suggest that tToll does not function as an LPS receptor on granular hemocytes. Cancer Metastasis Rev, 2004 Aug-Dec, 23(3-4), 323 - 31 Microbeam developments and applications: a low linear energy transfer perspective; Sowa Resat M et al.; In the last few years there has been a significant increase in the number of centers having, or developing, both high- and low-linear energy transfer (LET) microbeams for radiobiological investigations . In this review, we will discuss the various approaches for developing low-LET single cell irradiation devices and consider the instrument designs and how the machines capabilities can be exploited to investigate targeted and non-targeted effects of low-LET irradiation. Curr Opin Microbiol, 2004 Jun, 7(3), 283 - 9 Virulence gene expression in vivo; Shelburne SA et al.; The ability to identify and isolate bacterial RNA from animals or humans with infections has markedly advanced the capacity to examine microbial gene expression in vivo . This advance has been coupled with the development of quantitative real-time reverse transcription polymerase chain reaction and expression microarrays to allow investigators to accurately measure how organisms are manipulating their genetic expression during actual infections . Though the full ramifications of these technologies have yet to be realized, they promise to open new avenues of therapeutics for a broad range of infectious diseases by allowing researchers to focus on in vivo expressed genes . These developments provide a framework for efficient utilization of the vast amount of information being generated by the accelerating pace of genomic sequencing of microbes. Curr Opin Microbiol, 2004 Jun, 7(3), 245 - 54 Oligonucleotide microarrays in microbial diagnostics; Bodrossy L et al.; Oligonucleotide microarrays offer a fast, high-throughput alternative for the parallel detection of microbes from virtually any sample . The application potential spreads across most sectors of life sciences, including environmental microbiology and microbial ecology; human, veterinary, food and plant diagnostics; water quality control; industrial microbiology, and so on . The past two years have witnessed a rapid increase of research in this field . Many alternative techniques were developed and validated as seen in 'proof-of-concept' articles . Publications reporting on the application of oligonucleotide microarray technology for microbial diagnostics in microbiology driven projects have just started to appear . Current and future technical and bioinformatics developments will inevitably improve the potential of this technology further. Curr Opin Microbiol, 2004 Jun, 7(3), 239 - 44 The tritrophic trinity: a source of pollutant-degrading enzymes and its implications for phytoremediation; Singer AC et al.; Barring bioavailability and nutritional limitations, virtually all organic anthropogenic chemicals can be naturally biodegraded . It is to this phenomenon we owe thanks to the long established 'tritrophic trinity' of microbe-plant-insect interactions . Over hundreds of millennia these organisms have coevolved, producing hundreds of thousands of different chemicals that are used to attract, defend, antagonize, monitor and misdirect one another . In comparison, the numbers of truly novel chemicals of anthropogenic origin are negligible . It is only now that we are beginning to appreciate the fortuitous evolution of xenobiotic-degrading enzymes from these interactions . We argue that success in phytoremediation can be hastened through understanding the structure, sources, uses and targets of these secondary metabolites . Owing to recent developments in molecular biology, particularly stable isotope probing, we eagerly anticipate highly significant insights into trophic interactions, particularly in the rhizosphere, providing phytoremediation with a solid mechanistic understanding. Immunology, 2004 Jul, 112(3), 352 - 63 The increased prevalence of allergy and the hygiene hypothesis: missing immune deviation, reduced immune suppression, or both? Romagnani S. Allergic atopic disorders, such as rhinitis, asthma, and atopic dermatitis, are the result of a systemic inflammatory reaction triggered by type 2 T helper (Th2) cell-mediated immune responses against 'innocuous' antigens (allergens) of complex genetic and environmental origin . A number of epidemiological studies have suggested that the increase in the prevalence of allergic disorders that has occurred over the past few decades is attributable to a reduced microbial burden during childhood, as a consequence of Westernized lifestyle (the 'hygiene hypothesis') . However, the mechanisms by which the reduced exposure of children to pathogenic and nonpathogenic microbes results in enhanced responses of Th2 cells are still controversial . The initial interpretation proposed a missing immune deviation of allergen-specific responses from a Th2 to a type 1 Th (Th1) profile, as a result of the reduced production of interleukin-12 and interferons by natural immunity cells which are stimulated by bacterial products via their Toll-like receptors . More recently, the role of reduced activity of T regulatory cells has been emphasized . The epidemiological findings and the experimental evidence available so far suggest that both mechanisms may be involved . A better understanding of this question is important not only from a theoretical point of view, but also because of its therapeutic implications. Transplant Proc, 2004 May, 36(4), 1199 - 200 Short-term immunosuppression reduces fibrotic cellular infiltration around barium-M-alginate microbeads injected intraportally; Mathe Z et al.; INTRODUCTION: One of the major barriers affecting the viability of encapsulated islets is pericapsular fibrotic infiltration (PFI) . This study aimed to design strategies to reduce PFI around intraportally injected alginate microbeads . METHODS: Empty, highly purified, barium-M-alginate microbeads (400 microm) were injected intraportally into Lewis rats (3000 beads/rat) . Rats (n = 9/group) were treated daily with either rapamycine (RAPA; 1 mg/kg/d p.o.), tacrolimus (TAC; 2 mg/kg/d p.o.), a combination of both, or gadolinium-chloride (GdC13, 20 mg/kg/d i.v., at day -1 and day +4) . Treatment was discontinued at 10 days . Three rats/group were sacrificed at 3, 7, and 42 days after transplantation . Cellular composition of PFI was evaluated by immunohistochemistry . Severity of the reaction to the beads was determined by measuring the thickness of PFI on histology . RESULTS: The main cellular components of PFI in the liver were macrophages and myofibroblasts . There was a significant (P <.05) reduction in the thickness of PFI in all treated groups, even 6 weeks after transplantation . Encapsulated rat islets showed excellent insulin response to glucose in vitro, with a stimulation index of 3.6 +/- 2.0 . CONCLUSION: Combination of highly purified alginate with short-term immunosuppression reduces fibrotic overgrowth around microbeads injected intraportally. Biochimie, 2004 Apr-May, 86(4-5), 311 - 5 Dihydrodipicolinate synthase (DHDPS) from Escherichia coli displays partial mixed inhibition with respect to its first substrate, pyruvate; Dobson RC et al.; Dihydrodipicolinate synthase (DHDPS, E.C . 4.2.1.52) mediates the first unique reaction of (S)-lysine biosynthesis in plants and microbes-the condensation of (S)-aspartate-beta-semialdehyde ((S)-ASA) and pyruvate . It has been shown that DHDPS is partially feedback inhibited by (S)-lysine; it is suggested that this mechanism regulates flux through the DAP biosynthetic pathway . Others have characterised DHDPS from Escherichia coli with respect to (S)-lysine inhibition . They have concluded that, with respect to pyruvate, the first substrate of the reaction, DHDPS shows uncompetitive inhibition: as such, they further suggest that (S)-lysine inhibits DHDPS via interaction with the binding site for the second substrate, (S)-ASA . Yet, this finding is based on the assumption that (S)-lysine is a fully uncompetitive inhibitor . In light of crystallographic studies, which lead to the proposal that (S)-lysine affects the putative proton-relay of DHDPS, we re-evaluated the inhibition mechanism of DHDPS with respect to (S)-lysine by incorporating the observed hyperbolic inhibition . Our data showed that lysine is not an uncompetitive inhibitor, but a mixed inhibitor when pyruvate and (S)-lysine concentrations were varied . Thus, consistent with the crystallographic data, (S)-lysine must have an effect on the initial steps of the DHDPS reaction, including the binding of pyruvate and Schiff base formation. Curr Opin Biotechnol, 2004 Jun, 15(3), 191 - 8 Genome analysis of marine photosynthetic microbes and their global role; Hess WR; Four recently completed genome projects on marine Cyanobacteria have started the age of comparative genomics for marine microbes . Cyanobacteria are a group of photoautotrophic bacteria that have traditionally been under-represented in studies of complete genome sequences, as have microbes from the marine environment in general . The new genome information is of crucial importance to understanding their role in oceanic primary production, global carbon cycling and functioning of the biosphere . Marine microbes are a still almost untapped resource for the identification of novel beneficial metabolites and activities . The availability of an increasing number of genome sequences will eventually lead to a sustained development of marine biotechnology. Curr Opin Biotechnol, 2004 Jun, 15(3), 187 - 90 To BAC or not to BAC: marine ecogenomics; Beja O; Most microbes in the ocean are still resistant to our collective cultivation efforts . Environmental microbial genomics provides science with the means for accessing and assessing the genomes, diversity, evolution and population dynamics of uncultured microorganisms--the ocean's hidden majority. Med Parazitol (Mosk), 2004 Apr-Jun, (2), 3 - 6 {Seasonal features of the time course of changes in the aggregated state of the causative agent of plague in the organism of Citellophilus tesquorum altaicus (Siphonaptera)}; Bazanova LP et al.; The data of experiments made in a Tuva natural plague focus with the main vector of the flea C . lesquorum altaicus during different seasons are analyzed . Ectoparasites were infected with the plague microbial strain typical for the focus and fed on natural nourishment, such as long-tailed sousliks . An analysis indicated that estimation of the parameter "the proportion of infected insects containing the causative agent at the aggregated state" is of greater informative value than is the recording of only sporadic gizzard "blocks" . In experiments on fleas of a breeding of the current year, the conglomerates of the causative agent of plague were more frequently observed in males . All things being equal, the greatest efficiency of transmission of the microbe to the carriers of infection and the highest block formation in the fleas were observed in summer . The proportion of specimens with microbial conglomerates drastically increased in autumn during the preparation of the body of imagoes for hibernation . At this state, the microbe survived in the organism of a dormant carrier during winter . In spring, in the imagoes infected during the previous season, bacterial conglomerates were observed during the first feeds ten times more frequently than those in the insects of a breeding and infection of the current year. J Toxicol Environ Health A, 2004 Apr 23-May 28, 67(8-10), 819 - 34 Induced plant signaling and its implications for environmental sensing; De Moraes CM et al.; The sophisticated chemical responses of plants to environmental stimuli have profound implications for the development of remote sensing systems . Recent advances in the investigation of these responses have demonstrated that plants can be developed as reliable reporters of numerous environmental stimuli including soil and water conditions, light levels, temperature, mechanical damage, insect feeding, exposure to pathogens--including those that affect animals and humans--and exposure to airborne chemicals . Researchers are just beginning to understand the full range of plant phenotypic responses to these and other stimuli . These responses often have measurable physiological and molecular components that are readily observed . Other responses (e.g., internal biochemical changes) are less readily assayed, although sensing devices are being developed . Plant volatile emission "signatures" are particularly promising modes of plant reporting that can provide highly specific information regarding a diverse range of environmental variables on short time scales, but new approaches are needed for sensing these responses remotely . Modern molecular techniques promise to allow us to refine plant sensing and reporting, greatly enhancing the potential utility of plants as "sentinels." Continued basic research aimed at characterizing the physiological, biochemical, and molecular responses of plants to environmental stimuli (including airborne chemicals, insects and pathogenic microbes) are essential to achieving that promise. J Toxicol Environ Health A, 2004 Apr 23-May 28, 67(8-10), 651 - 66 Predictive population dose-response assessment for Cryptosporidium parvum: infection endpoint; Englehardt JD et al.; Data validation of safe doses of pathogens in drinking water consistent with public health goals is not possible due to the number of subjects that would be needed at each dose . Because of this problem, together with the difficulty in extrapolating pathogenic response between species, and the ability of microbes to adapt rapidly, confidence-level-dependent assessments of Cryptosporidium parvum dose-response have been developed . However, these results, even on a relative basis, are dependent on confidence level, and the lack of scientific basis for this choice hampers efforts to set water quality standards . Therefore, a predictive Bayesian dose-response assessment method was proposed previously . In this article, a hierarchical predictive population dose-response Bayesian assessment for C . parvum is presented for the infection endpoint . Available data on the infectivity of three isolates of C . parvum, genotype C, were adjusted for sensitive and antibody-positive subpopulations not proportionately represented in the data, by bootstrap analysis . The diverse mean infectivities of the isolates were used to obtain a predictive distribution for population infectivity, used in turn to obtain the predictive population dose-response function . The predictive result is a distribution of unconditional probability of infection, based on available dose-response information . Information includes theoretical and empirical evidence for the conditional beta-Poisson parametric dose-response function . Results indicate that a dose of 6 x 10(-6) oocysts per exposure corresponds to 10(-4) infections per capita year . An allowable dose corresponding to goals of the SWTR should be increased over this value to reflect the illness endpoint, while potentially being reduced to account for secondary transmission among hosts if important for gastroenteritis in developed countries. Science, 2004 Jun 11, 304(5677), 1634 - 7 Interactions and self-organization in the soil-microbe complex; Young IM et al.; Soil is the most complicated biomaterial on the planet . As with any material, the physical habitat is of prime importance in determining and regulating biological activity . However, until recently the opaque nature of soil has meant that any interrogation of its interior architecture has been relatively rudimentary, restricted to simple qualitative expressions of the physical heterogeneity that fail to relate to any specific function . However, new techniques and insights into the biophysical and biochemical processes of this inner space are leading to the developments of theoretical frameworks and experimental approaches that will allow us to sustainably manage Earth's most important resource . We introduce the concept that the soil-microbe system is self-organized and suggest new priorities for research based on an integrative approach that combines biochemistry and biophysics. Tissue Antigens, 2004 Jul, 64(1), 13 - 7 Donor-specific sensitization by cadaveric venous allografts used for arterial reconstruction in peripheral arterial occlusive vascular disease; Balzer KM et al.; The use of allogeneic venous grafts from postmortal organ donors allows for the reconstruction of critically affected arteries in patients with peripheral occlusive vascular disease . We were interested to determine the prevalence and specificity of anti-HLA antibodies in patients after allogeneic vein transplantation . Anti-HLA class I and II alloantibodies were analyzed by flowcytometric analysis using color-coded microbeads coated with HLA antigens including recombinant single antigens . Nine out of 10 patients involving 12 venous allografts were positive for anti-HLA alloantibodies . All antibody-positive patients carried both anti-HLA class I and II alloantibodies . Anti-donor HLA specificity of the anti-HLA alloantibodies was seen in seven out of nine patients for anti-class I antibodies and in eight out of nine patients for anti-HLA class II antibodies . A high rate of donor-specific allosensitization was seen after allogeneic venous transplantation . In conclusion, allosensitization not only includes a humoral response against the constitutively expressed class I antigens but also extends to class II antigens. Microbiol Mol Biol Rev, 2004 Jun, 68(2), 345 - 61 Microbial responses to microgravity and other low-shear environments; Nickerson CA et al.; Microbial adaptation to environmental stimuli is essential for survival . While several of these stimuli have been studied in detail, recent studies have demonstrated an important role for a novel environmental parameter in which microgravity and the low fluid shear dynamics associated with microgravity globally regulate microbial gene expression, physiology, and pathogenesis . In addition to analyzing fundamental questions about microbial responses to spaceflight, these studies have demonstrated important applications for microbial responses to a ground-based, low-shear stress environment similar to that encountered during spaceflight . Moreover, the low-shear growth environment sensed by microbes during microgravity of spaceflight and during ground-based microgravity analogue culture is relevant to those encountered during their natural life cycles on Earth . While no mechanism has been clearly defined to explain how the mechanical force of fluid shear transmits intracellular signals to microbial cells at the molecular level, the fact that cross talk exists between microbial signal transduction systems holds intriguing possibilities that future studies might reveal common mechanotransduction themes between these systems and those used to sense and respond to low-shear stress and changes in gravitation forces . The study of microbial mechanotransduction may identify common conserved mechanisms used by cells to perceive changes in mechanical and/or physical forces, and it has the potential to provide valuable insight for understanding mechanosensing mechanisms in higher organisms . This review summarizes recent and future research trends aimed at understanding the dynamic effects of changes in the mechanical forces that occur in microgravity and other low-shear environments on a wide variety of important microbial parameters. Appl Environ Microbiol, 2004 Jun, 70(6), 3650 - 63 Sequence-specific cleavage of small-subunit (SSU) rRNA with oligonucleotides and RNase H: a rapid and simple approach to SSU rRNA-based quantitative detection of microorganisms; Uyeno Y et al.; A rapid and simple approach to the small-subunit (SSU) rRNA-based quantitative detection of a specific group of microorganisms in complex ecosystems has been developed . The method employs sequence-specific cleavage of rRNA molecules with oligonucleotides and RNase H . Defined mixtures of SSU rRNAs were mixed with an oligonucleotide (referred to as a "scissor probe") that was specifically designed to hybridize with a particular site of targeted rRNA and were subsequently digested with RNase H to proceed to sequence-dependent rRNA scission at the hybridization site . Under appropriate reaction conditions, the targeted rRNAs were correctly cut into two fragments, whereas nontargeted rRNAs remained intact under the same conditions . The specificity of the cleavage could be properly adjusted by controlling the hybridization stringency between the rRNA and the oligonucleotides, i.e., by controlling either the temperature of the reaction or the formamide concentration in the hybridization-digestion buffer used for the reaction . This enabled the reliable discrimination of completely matched rRNA sequences from single-base mismatched sequences . For the detection of targeted rRNAs, the resulting RNA fragment patterns were analyzed by gel electrophoresis with nucleotide-staining fluorescent dyes in order to separate cleaved and intact rRNA molecules . The relative abundance of the targeted SSU rRNA fragments in the total SSU rRNA could easily be calculated without the use of an external standard by determining the signal intensity of individual SSU rRNA bands in the electropherogram . This approach provides a fast and easy means of identification, detection, and quantification of a particular group of microbes in clinical and environmental specimens based on rRNA. Anal Biochem, 2004 Jul 1, 330(1), 70 - 3 Lipase assay in soils by copper soap colorimetry; Saisuburamaniyan N et al.; A simple and sensitive method for the estimation of lipase activity in soils is reported . In this method, 50mg of soil is incubated with emulsified substrate, the fatty acids liberated are treated with cupric acetate-pyridine reagent, and the color developed is measured at 715 nm . Use of olive oil in this protocol leads to an estimation of true lipase activity in soils . The problem of released fatty acids getting adsorbed onto the soil colloids is obviated by the use of isooctane, and separate standards for different soils need not be developed . Among the various surfactants used for emulsification, polyvinyl alcohol is found to be the most effective . Incubation time of 20 min, soil concentration of 50 mg, pH 6.5, and incubation temperature of 37 degrees C were found to be the most suitable conditions for this assay . During the process of enrichment of the soils with oil, interference by the added oil is avoided by the maintenance of a suitable control, wherein 50 mg of soil is added after stopping the reaction . This assay is sensitive and it could be adopted to screen for lipase producers from enriched soils and oil-contaminated soils before resorting to isolation of the microbes by classical screening methods. Mod Pathol, 2004 Oct, 17(10), 1211 - 6 Correlation between karyotype and quantitative immunophenotype in acute myelogenous leukemia with t(8;21); Khoury H et al.; Acute myelogenous leukemia with t(8;21) is a distinct clinicopathologic entity in which the malignant myeloblasts display a characteristic pattern of surface antigen expression . Quantitative analysis of surface marker expression in patients with this chromosomal abnormality compared to acute myelogenous leukemia patients with a different karyotype has not been reported . From 305 consecutive newly diagnosed acute myelogenous leukemia patients underwent immunophenotyping and cytogenetic analysis at our center; 16 patients (5.2%) had a t(8;21) . Fluorescence intensity values were obtained, using a set of reference microbeads, by conversion of mean channel fluorescence to molecular equivalent of soluble fluorochrome . Patients with t(8;21) displayed higher levels of CD34, HLA-DR and MPO expression (P < 0.001 for each) and lower levels of CD13 (P = 0.03) and CD33 (P = 0.02) expression . In order to study the sensitivity, specificity and predictive value of these markers, molecular equivalent of soluble fluorochrome thresholds were statistically determined . The statistically established threshold for each of the individual markers (CD34 > 60.5 x 10(3), HLA-DR > 176.1 x 10(3), MPO > 735.1 x 10(3), CD13 < 24.3 x 10(3) and CD33 < 17.3 x 10(3)) had a sensitivity of 100%, a specificity of 62-92% and a positive predictive value of 7-45% . In multivariate analysis, two quantitative patterns (CD34 > 60.5 x 10(3) and MPO > 176.1 x 10(3); CD33 < 17.3 x 10(3) and MPO > 176.1 x 10(3)) had a sensitivity, specificity and positive predictive value of 100% . These aberrant phenotypic patterns might help identify patients with t(8;21) at diagnosis and could be useful in minimal residual disease monitoring. Immunol Res, 2004, 29(1-3), 187 - 96 Modulating TH1/TH2 responses with microbes, dendritic cells, and pathogen recognition receptors; Pulendran B; The adaptive immune system has evolved different types of immune responses, each one effective against a given class of pathogen . For example, Th1 and Th2 responses represent two qualitatively different types of immune responses that are preferentially effective against intracellular microbes and helminths, respectively . Since the original description of Th1 and Th2 T-cell clones (1), we have learned much about the cytokines that influence the type of Th response . Thus, interleukin-4 (IL-4) is known to induce IL-4 production in T cells; conversely IL-12 and interferon-gamma (IFN-gamma) are known to induce IFN-gamma production by T cells . However, the original sources of these cytokines in vivo are less clear . Recent developments from several labs point to a potential role for dendritic cells (DCs) in orchestrating this decision making process . Here, we present our current view of DC development, and then review the evidence for two opposing concepts: (1) that distinct subsets of DCs are predetermined to differentially bias the T-helper response; and (2) that microbes and the local microenvironment are potent modulators of DC function . Thus, nature appears to have evolved different mechanisms to regulate immune responses via DCs. Biometrics, 2004 Jun, 60(2), 461 - 70 Self modeling with flexible, random time transformations; Brumback LC et al.; Methods for modeling sets of complex curves where the curves must be aligned in time (or in another continuous predictor) fall into the general class of functional data analysis and include self-modeling regression and time-warping procedures . Self-modeling regression (SEMOR), also known as a shape invariant model (SIM), assumes the curves have a common shape, modeled nonparametrically, and curve-specific differences in amplitude and timing, traditionally modeled by linear transformations . When curves contain multiple features that need to be aligned in time, SEMOR may be inadequate since a linear time transformation generally cannot align more than one feature . Time warping procedures focus on timing variability and on finding flexible time warps to align multiple data features . We draw on these methods to develop a SIM that models the time transformations as random, flexible, monotone functions . The model is motivated by speech movement data from the University of Wisconsin X-ray microbeam speech production project and is applied to these data to test the effect of different speaking conditions on the shape and relative timing of movement profiles. Anal Bioanal Chem, 2004 Jun, 379(4), 622 - 7 Epub 2004 Jun 04. Ion-beam analysis of CuInSe2 solar cells deposited on polyimide foil; Spemann D et al.; CuInSe(2) (CIS) solar cells deposited on polyimide foil by the Solarion company in a web-coater-based process using sputter and evaporation techniques were investigated in the ion beam laboratory LIPSION of the University of Leipzig by means of Rutherford backscattering spectrometry (RBS) and particle-induced X-ray emission (PIXE) using high-energy broad ion beams and microbeams . From these measurements the composition of the absorber and the lateral homogeneity and film thicknesses of the individual layers could be determined on the basis of some reasonable assumptions . For the first time, quantitative depth profiling of the individual elements was performed by microPIXE measurements on a beveled section prepared by ion-beam etching of a CIS solar cell . Within the CIS absorber layer no significant concentration-depth gradients were found for Cu, In, and Se, in contrast with results from secondary neutral mass spectrometry (SNMS) depth profiling, which was applied to the same samples for comparison . Furthermore, both PIXE and SNMS showed the presence of a remarkable amount of Cd from the CdS buffer layer in the underlying absorber. Science, 2004 Jun 4, 304(5676), 1463 - 6 Challenges of modeling ocean basin ecosystems; deYoung B et al.; With increasing pressure for a more ecological approach to marine fisheries and environmental management, there is a growing need to understand and predict changes in marine ecosystems . Biogeochemical and physical oceanographic models are well developed, but extending these further up the food web to include zooplankton and fish is a major challenge . The difficulty arises because organisms at higher trophic levels are longer lived, with important variability in abundance and distribution at basin and decadal scales . Those organisms at higher trophic levels also have complex life histories compared to microbes, further complicating their coupling to lower trophic levels and the physical system . We discuss a strategy that builds on recent advances in modeling and observations and suggest a way forward that includes approaches to coupling across trophic levels and the inclusion of uncertainty. J Microbiol Methods, 2004 Jul, 58(1), 119 - 29 13CO2 pulse labelling of plants in tandem with stable isotope probing: methodological considerations for examining microbial function in the rhizosphere; Griffiths RI et al.; Recently developed 13CO2 pulse labelling and stable isotope probing (SIP) methods offer the potential to track 13C-labelled plant photosynthate into phylogenetic groups of microbial taxa in the rhizosphere, permitting an examination of the link between soil microbial diversity and carbon flow in situ . We tested the feasibility of this approach to detect functional differences in microbial communities utilising recently fixed plant photosynthate in moisture perturbed grassland turfs . Specifically, we addressed two questions: (1) How does moisture perturbation (three treatments; continual wetting, drying, and drying followed by rewetting) affect the assimilation of 13C-labelled exudates carbon into the soil microbial community?; (2) Can 13C deposited in soil from pulse-labelled plants be used to identify microbes utilising plant exudates using SIP methodologies? Net CO2 fluxes showed that prior to 13CO2 pulse labelling, all treatments were photosynthetically active, but differences were observed in night time respiration, indicating moisture treatments had impacted on net CO2 efflux . Measurements of pulse-derived 13C incorporated into soil RNA over 2 months showed that there was only evidence of 13C enrichment in the continuously wetted treatments . However, isotopic values represented only a 0.1-0.2 13C at.% increase over natural abundance levels and were found to be insufficient for the application of RNA-SIP . These findings reveal that in this experimental system, the microbial uptake of labelled carbon from plant exudates is low, and further optimisation of methodologies may be required for application of SIP to natural plant-soil systems where 13C tracer dilution is a consideration . J Hazard Mater, 2004 Jun 18, 109(1-3), 201 - 11 Performance of BTX degraders under substrate versatility conditions; Maliyekkal SM et al.; A microbial consortium acclimatized with benzene, toluene or xylene (BTX) was employed to study the degradation pattern of these compounds individually under aerobic conditions . Batch and continuous experiments were conducted to evaluate the adaptability of the enriched cultures under substrate versatility conditions . The bio-kinetic parameters obtained under substrate versatility conditions were compared with those of a single substrate condition . Similar degradation patterns were observed for all the substrates with inhibition occurring at higher concentration (approximately 150 mg/L for benzene and xylene, and approximately 200 mg/L for toluene) . Toluene degradation was highest, followed by benzene and xylene in the aqueous phase . Adaptation to a more toxic compound like benzene and xylene improved the utilization of toluene . On the other hand, microbes grown on a less toxic compound (toluene) grew at a lower rate in the presence of more toxic compounds . Suitable kinetic parameters such as micro(max) (maximum specific growth rate per hour), Ks (half saturation constant, mg/L), and KI (threshold substrate inhibition constant, mg/L) were determined using Haldane and Levenspiel substrate inhibition models . The Haldane equation seems to be an adequate expression for the system . The degradation behavior of pollutants in the gas phase was also evaluated using a toluene acclimatized biotrickling filter operated in continuous mode . The biotrickling filter acclimatized with toluene could degrade benzene and xylene with a lower elimination capacity . But, the system could recover its original efficiency quite fast even after a prolonged shock loading . The degradation was better for toluene, followed by benzene and xylene. Am J Physiol Cell Physiol, 2004 Sep, 287(3), C643 - 54 Epub 2004 Jun 02. Cytoskeletal mechanics in adherent human airway smooth muscle cells: probe specificity and scaling of protein-protein dynamics; Puig-de-Morales M et al.; We probed elastic and loss moduli in the adherent human airway smooth muscle cell through a variety of receptor systems, each serving as a different molecular window on cytoskeletal dynamics . Coated magnetic microbeads were attached to the cell surface via coating-receptor binding . A panel of bead coatings was investigated: a peptide containing the sequence RGD, vitronectin, urokinase, activating antibody against beta(1)-integrin, nonactivating antibody against beta(1)-integrin, blocking antibody against beta(1)-integrin, antibody against beta(1)-integrin, and acetylated low-density lipoprotein . An oscillatory mechanical torque was applied to the bead, and resulting lateral displacements were measured at baseline, after actin disruption by cytochalasin D, or after contractile activation by histamine . As expected, mechanical moduli depended strongly on bead type and bead coating, differing at the extremes by as much as two orders of magnitude . In every case, however, elastic and loss moduli increased with frequency f as a weak power law, f( x-1) . Moreover, with few exceptions, data could be scaled such that elastic and frictional responses depended solely on the power law exponent x . Taken together, these data suggest that power law behavior represents a generic feature of underlying protein-protein dynamics. Microb Cell Fact . 2004 Jun 2;3(1):7. Potential use of sugar binding proteins in reactors for regeneration of CO2 fixation acceptor D-Ribulose-1,5-bisphosphate; Mahato S et al.; Sugar binding proteins and binders of intermediate sugar metabolites derived from microbes are increasingly being used as reagents in new and expanding areas of biotechnology . The fixation of carbon dioxide at emission source has recently emerged as a technology with potentially significant implications for environmental biotechnology . Carbon dioxide is fixed onto a five carbon sugar D-ribulose-1,5-bisphosphate . We present a review of enzymatic and non-enzymatic binding proteins, for 3-phosphoglycerate (3PGA), 3-phosphoglyceraldehyde (3PGAL), dihydroxyacetone phosphate (DHAP), xylulose-5-phosphate (X5P) and ribulose-1,5-bisphosphate (RuBP) which could be potentially used in reactors regenerating RuBP from 3PGA . A series of reactors combined in a linear fashion has been previously shown to convert 3-PGA, (the product of fixed CO2 on RuBP as starting material) into RuBP (Bhattacharya et al., 2004; Bhattacharya, 2001) . This was the basis for designing reactors harboring enzyme complexes/mixtures instead of linear combination of single-enzyme reactors for conversion of 3PGA into RuBP . Specific sugars in such enzyme-complex harboring reactors requires removal at key steps and fed to different reactors necessitating reversible sugar binders . In this review we present an account of existing microbial sugar binding proteins and their potential utility in these operations. West Afr J Med, 2004 Jan-Mar, 23(1), 54 - 7 Intracerebral abscesses: outcome following management in the CT era; Emejulu JK et al.; BACKGROUND: There are no pathognomonic presenting features of intracerebral abscesses . Their clinical features could be confused with those of a tumour or any other space occupying lesion . STUDY DESIGN: We analyzed the symptoms, predisposing factors, diagnostic modalities, prevalent causative microbes, management and outcome in 11 patients, for whom complete records were available and who were managed for confirmed intracerebral abscess in our Neurosurgical Unit from 1996 to 2000 and compared our findings with those from other series . RESULTS: In these patients focal neurological deficit was the most common clinical feature, trauma was the most predisposing event and Computerised Tomography (CT) Scanning remained the most dependable diagnostic tool . In our practice, burr hole drainage augmented with a minimum of 4 weeks intravenous antibiotics, was the most frequently used treatment modality . CONCLUSION: The outcome was satisfactory (ability to return to pre-morbid activities and duties, with no disabling neurological deficits) in 72.8% cases . There was one death . This modality remains an effective way of treating patients with intracebrebral abscess. Trends Microbiol, 2004 Jun, 12(6), 259 - 63 The weapon potential of a microbe; Casadevall A et al.; The designation of a microbe as a potential biological weapon poses the vexing question of how such a decision is made given the many pathogenic microbes that cause disease . Analysis of the properties of microbes that are currently considered biological weapons against humans revealed no obvious relationship to virulence, except that all are pathogenic for humans . Notably, the weapon potential of a microbe rather than its pathogenic properties or virulence appeared to be the major consideration when categorizing certain agents as biological weapons . In an effort to standardize the assessment of the risk that is posed by microbes as biological warfare agents using the basic principles of microbial communicability (defined here as a parameter of transmission) and virulence, a simple formula is proposed for estimating the weapon potential of a microbe. Int J Antimicrob Agents, 2004 Mar, 23(3), 209 - 12 Antibiotic resistance from two perspectives: man and microbe; Hamilton-Miller JM; Despite much effort, antibiotic resistance continues to increase . Looking back, it is clear that this was an inevitable consequence of antibiotic use . From a bacterial viewpoint, the introduction of antibiotics was a tremendous stimulus to evolution . As a survival reaction to stress (selection pressure) bacteria, by means of their extreme biochemical and genetic versatility, have adapted to 21st Century conditions . Resistance can be to some extent contained by less and better use of antibiotics, but ultimately novel approaches to the treatment and prevention of infectious diseases will have to be forthcoming . This will only be achieved if best use is made of alternative resources presently available and most importantly, man's ingenuity must be fully engaged. Mol Gen Mikrobiol Virusol, 2004, (2), 24 - 8 {Genotyping of the Francisella tularensis strains isolated from natural foci of tularemia in the Rostov region by multilocus VNTR analysis}; Vodop'ianov AS et al.; On the basis of an analysis of the VNTR alleles' distribution in 109 strains of F . tularensis it was established that 19 genotypes of the disease causative agent circulated in the Rostov Region from 1945 to 2002 . The microbe-provoked infection episodes can be divided into polyclonal, monoclonal and cluster ones . A retrospective analysis of the genotypes' distribution is indicative of that strains of similar or of closely-related genotypes circulate simultaneously in the studied territory . All investigated F . tularensis strains could be differentiated into two groups; strains, whose genotypes are encountered almost evenly within the entire Region's territory, belong to group 1; and strains of group 2 displayed a trend towards being geographically bound . Isolations of cultures with similar (close) genotypic features made in prolonged time periods suggest that a part of F . tularensis clones can persist for a long time in environmental foci . A set of strains described by genotype can provide a foundation for a database of the tularemic microbe culture within the geo-information system of the South Federative Okrug of Russia. Microbes Infect, 2004 May, 6(6), 609 - 16 Innate immune recognition of microbes through Nod1 and Nod2: implications for disease; Carneiro LA et al.; Nod1 and Nod2 are cytosolic proteins involved in intracellular recognition of microbes and their products . Recently, it was shown that these proteins recognize different moieties of bacterial peptidoglycan (PGN) mediating non-specific pathogen resistance and possibly generating signals for the adaptive immune response . Moreover, mutations in the gene encoding Nod2 are associated with increased susceptibility to chronic inflammatory disorders. Infect Genet Evol, 2004 Jun, 4(2), 159 - 66 The best defence against bioweapons has already been invented by evolution; Rumyantsev SN; Bioweapons are considered from the viewpoint of the mutual evolution of microbe/victim ecological systems . Cases considered include accidental, experimental, and real exploitation of bioweapons as well as other cases in the history of epidemics, and also experimental investigations . It is proposed here that speculations about bioweapon's very high mass annihilating ability are based on over-extrapolation from limited data selected from the ancient history of epidemics and on a false supposition that all people are susceptible to any bioweapon's infectious agent . The history of epidemics, clinical and genetic observations, data from experimental investigations, and results of accidental, experimental, and real exploitation of bioweapons do not confirm the mass annihilating capability of bioweapons . Many people possess constitutional (genetic) immunity presumably formed by natural selection over many human generations . This genetic protection exists in an individual prior to infection . The power of constitutional immunity played an important role during all human evolution . Its protective capability continues to defend humanity from mass annihilation by both epidemics and bioweapons . In this context of constitutional immunity for the majority of individuals, the main goal of modern medicine is to identify and defend the defenseless ones. J Speech Lang Hear Res, 2004 Apr, 47(2), 342 - 52 Use of electromagnetic midsagittal articulography in the study of swallowing; Steele CM et al.; The tongue functions as the primary articulator during the oropharyngeal stages of swallowing . However, detailed descriptions of the kinematics and spatiotemporal variability of tongue behaviors during swallowing are limited to a handful of analyses of data from the X-ray microbeam database . In this article, a new technique, electromagnetic midsagittal articulography (EMMA), is introduced for the high-resolution description of oral articulatory movements during swallowing . Data from 8 healthy, nondysphagic participants are used to illustrate the methods used for data collection and analysis . Movement data were collected for 3 fleshpoint positions on the tongue (blade, body, dorsum) during sequences of repeated discrete water swallows, and were characterized for variables of spatiotemporal variability and 4 discrete kinematic parameters (movement amplitude, peak velocity, duration, and kinematic stiffness) . These data show that the movement trajectories measured using EMMA are consistent with descriptions from previous X-ray microbeam studies, indicating that EMMA is a feasible method for the detailed study of tongue movements during swallowing. J Immunol, 2004 Jun 1, 172(11), 6978 - 87 Toll-like receptor 4 signaling by intestinal microbes influences susceptibility to food allergy; Bashir ME et al.; The mechanisms by which signaling by the innate immune system controls susceptibility to allergy are poorly understood . In this report, we show that intragastric administration of a food allergen with a mucosal adjuvant induces allergen-specific IgE, elevated plasma histamine levels, and anaphylactic symptoms in three different strains of mice lacking a functional receptor for bacterial LPS (Toll-like receptor 4 (TLR4)), but not in MHC-matched or congenic controls . Susceptibility to allergy correlates with a Th2-biased cytokine response in both the mucosal (mesenteric lymph node and Peyer's patch) and systemic (spleen) tissues of TLR4-mutant or -deficient mice . TLR4-mutant mice are not inherently impaired in their ability to regulate Th1 cytokine production because they respond to stimulation via TLR9 . Coadministration of CpG oligodeoxynucleotides during sensitization of TLR4-mutant mice with allergen plus CT abrogates anaphylactic symptoms and Ag-specific IgE, and results in a Th1-polarized cytokine response . When the composition of the bacterial flora is reduced and altered by antibiotic administration (beginning at 2 wk of age), TLR4 wild-type mice become as susceptible to the induction of allergy as their TLR4-mutant counterparts . Both allergen-specific IgE and Th2 cytokine responses are reduced in antibiotic-treated mice in which the flora has been allowed to repopulate . Taken together, our results suggest that TLR4-dependent signals provided by the intestinal commensal flora inhibit the development of allergic responses to food Ags. Am Fam Physician, 2004 May 1, 69(9), 2248 - 9 Sinus and Allergy Health Partnership releases report on adult chronic rhinosinusitis; Ressel G; The report states that chronic rhinosinusitis is an evolving area of study and new information is being assessed on an ongoing basis . Debate continues about potential etiologies and associated conditions, pathophysiology, common inflammatory mediators, and whether or not most cases of chronic rhinosinusitis are associated with infection . Evidence in the most recent literature supports the significant role that microbes (i.e., bacteria, fungi) play in the inflammatory process . The report discusses classification schemes, the role of potential bacterial, allergic, and fungal etiologies, and the controversies about these areas of study. Sci STKE . 2004 May 11;2004(233):pe21. During the respiratory burst, do phagocytes need proton channels or potassium channels, or both? DeCoursey TE. The NADPH (reduced form of nicotinamide adenine dinucleotide phosphate) oxidase enzyme complex, a crucial component of innate immunity, produces superoxide anion (O2-), which is a precursor to many reactive oxygen species . NADPH oxidase produces O2- by transferring electrons from intracellular NADPH across the membrane to extracellular (or phagosomal) oxygen and is thus electrogenic . It is widely believed that electroneutrality is preserved by proton flux through voltage-gated proton channels . A series of recent papers have challenged several key aspects of this view of the "respiratory burst." The most recent study solidifies the proposal that O2- and other reactive oxygen species produced by phagocytes are not toxic to microbes under physiological conditions . Further, an essential role for high-conductance, Ca2+-activated K+ (maxi-K+) channels in microbe killing is proposed . Finally, the results cast doubt on the widely held view that H+ efflux through voltage-gated proton channels (i) is the main mechanism of charge compensation, and (ii) is essential to continuous O2- production by the NADPH oxidase . My analysis of the new data and of a large body of data in the literature indicates that the proposed role of maxi-K+ channels in the respiratory burst is not yet credibly established . H+ efflux through proton channels thus remains the most viable mechanism for charge compensation and continuous O2- production . The important question of the toxicity of reactive oxygen species in phagocytes and in other cells, which has long been simply taken for granted, is a widespread assumption that deserves critical study. Vaccine, 2004 Jun 2, 22(17-18), 2106 - 15 Sub-compartmentalization of the gastrointestinal (GI) immune system determined with microbeads that differ in release properties; Cronkhite RI et al.; Immunization of two specific regions of the murine GI tract of two types of mice with ovalbumin (OVA) encapsulated in microbeads with two different pH-sensitive coatings allowed a more precise analysis of this compartment of the mucosal immune system . Acute, chronic and pervasive immunization protocols were utilized in an attempt to stimulate specific types of immunity . Chronic immunization potentiated antibody isotypes influenced by type 2 T helper cells (T(h)2) . Pervasive immunization of both regions of the GI tract mimicked chronic immunization, stimulating high levels of OVA-reactive IgE . Acute immunization was best able to potentiate isotypes influenced by type 1 T helper cells (T(h)1) and a sequential segregated immunization protocol allowed the targeting of T(h)1-like memory responses. Int J Med Microbiol, 2004 Apr, 293(7-8), 453 - 61 Pathogenomics of mobile genetic elements of toxigenic bacteria; Hacker J et al.; The growing knowledge of genetic diversity and whole genome organization in bacteria shows that pathogenicity islands (PAIs) represent a subtype of a more general genetic element, termed genomic island (GEI), which is widespread among pathogenic and non-pathogenic microbes . These findings mirror the importance of horizontal gene transfer, genome reduction and recombination events as fundamental mechanisms involved in evolution of bacterial variants . GEIs are part of the flexible gene pool and carry selfish genes, but also determinants which may be beneficial under certain conditions thus increasing bacterial fitness and consequently their survival or transmission . In this review, we focus on the role of mobile genetic elements that may also contain toxin-encoding genes for genome variability and evolution of bacteria. Arch Dermatol Res, 2004 Aug, 296(3), 120 - 4 Epub 2004 May 18. Differentiation-regulated expression of Toll-like receptors 2 and 4 in HaCaT keratinocytes; Pivarcsi A et al.; Toll-like receptors (TLRs) play an important role in the recognition of pathogens in keratinocytes . In this study, we investigated whether the differentiation state of HaCaT keratinocytes correlates with the expression of TLR2 and TLR4 genes . The expression levels of TLR2 and TLR4 in a HaCaT differentiation model system were determined using quantitative real-time RT-PCR (Q-RT-PCR) and flow cytometry . The progression of keratinocyte differentiation was monitored by determining the level of involucrin gene expression using Q-RT-PCR . The expression levels of TLR2 and TLR4 increased with the stage of differentiation and there were strong correlations between the expression level of the involucrin gene and those of the TLR2 gene ( r=0.809, P<0.0001) and the TLR4 gene ( r=0.568, P<0.02) . Increased cell surface expression of TLR2 and TLR4 was also found in differentiated HaCaT keratinocytes by flow cytometric analysis . Our findings suggest that upregulation of TLR expression during differentiation in keratinocytes could be a part of the differentiation process of keratinocytes and could have biological significance in protecting skin against microbes. Methods Mol Biol, 2004, 266, 261 - 87 Using the genome to understand pathogenicity; Field D et al.; Genome sequencing, the determination of the complete complement of DNA in an organism, is revolutionizing all aspects of the biological sciences . Genome sequences make available for scientific scrutiny the complete genetic capacity of an organism . With respect to microbes, this means we now have the unprecedented opportunity to investigate the molecular basis of commensal and virulence behavior . We now have genome sequences for a wide range of bacterial pathogens (obligate, facultative, and opportunistic); this has facilitated the discovery of many previously unidentified determinants of pathogenicity and has provided novel insights into what creates a pathogen . In-depth analyses of bacterial genomes are also providing new perspectives on bacterial physiology, molecular adaptation to a preferred niche, and genomic susceptibility to the uptake of foreign DNA, three key factors that can play a significant role in determining whether a species, or a strain, will have pathogenic potential. Methods Mol Biol, 2004, 266, 71 - 113 Genome plasticity: insertion sequence elements, transposons and integrons, and DNA rearrangement; Bennett PM; Living organisms are defined by the genes they possess . Control of expression of this gene set, both temporally and in response to the environment, determines whether an organism can survive changing conditions and can compete for the resources it needs to reproduce . Bacteria are no exception; changes to the genome will, in general, threaten the ability of the microbe to survive, but acquisition of new genes may enhance its chances of survival by allowing growth in a previously hostile environment . For example, acquisition of an antibiotic resistance gene by a bacterial pathogen can permit it to thrive in the presence of an antibiotic that would otherwise kill it; this may compromise clinical treatments . Many forces, chemical and genetic, can alter the genetic content of DNA by locally changing its nucleotide sequence . Notable for genetic change in bacteria are transposable elements and site-specific recombination systems such as integrons . Many of the former can mobilize genes from one replicon to another, including chromosome-plasmid translocation, thus establishing conditions for interspecies gene transfer . Balancing this, transposition activity can result in loss or rearrangement of DNA sequences . This chapter discusses bacterial DNA transfer systems, transposable elements and integrons, and the contributions each makes towards the evolution of bacterial genomes, particularly in relation to bacterial pathogenesis . It highlights the variety of phylogenetically distinct transposable elements, the variety of transposition mechanisms, and some of the implications of rearranging DNA, and addresses the effects of genetic change on the fitness of the microbe. Biochem Biophys Res Commun, 2004 Jun 11, 318(4), 1025 - 30 Evidences showing ultraviolet-B radiation-induced damage of DNA in cyanobacteria and its detection by PCR assay; Kumar A et al.; Impact of ultraviolet-B radiation in causing the damages to the DNA of the cyanobacterium, Anabaena strain BT2 has been investigated . Exposure of genomic DNA (in vitro) to UV-B radiation for 1 h did not cause any shift in the absorption peak (lambda(max)) but more than 30% increase in absorbance was noticed in comparison to untreated control DNA (no exposure to UV-B) . This increase in absorbance in a way may be comparable to typical hypochromic effect but there was no decrease in absorbance following transfer of UV-B-treated DNA to fluorescent light or in the dark . That the damaging effect of UV-B radiation on native structure of DNA is indeed real was also evident from the PCR-based assay such as RAPD, rDNA amplification, and ARDRA . Template activity of UV-B-treated genomic DNA was drastically inhibited, there was no amplification in RAPD assay after prior exposure of DNA to UV-B for 60 min . Only one band of approximately 400 bp was observed even after 60 min of exposure which suggests that certain segment of DNA strand is resistant to UV-B effects . Similar to the effects on RAPD profile, amplification of rDNA was significantly inhibited following exposure of genomic DNA to UV-B . Our findings clearly demonstrate that UV-B does affect the DNA of cyanobacteria and the killings of these microbes might be due to the irreversible damages caused to DNA by this high energy radiation . It is felt that PCR assay may be conveniently used for screening the damages caused to DNA by UV-B radiation in cyanobacteria and other microorganisms. Clin Exp Immunol, 2004 Jun, 136(3), 521 - 6 Expression and subcellular distribution of toll-like receptors TLR4, TLR5 and TLR9 on the gastric epithelium in Helicobacter pylori infection; Schmausser B et al.; Toll-like receptors (TLRs) expressed by mucosal epithelium play an essential role in the defense against microbes by recognizing conserved bacterial molecules . For the first time TLR4, TLR5 and TLR9 have been microanatomically localized in patients with noninflamed gastric mucosa and Helicobacter pylori gastritis by immunohistochemistry . Because polarized expression of TLRs in apical and basolateral epithelial compartments is thought to modulate mucosal immunity, subcellular TLR distribution by gastric epithelium was investigated using confocal microscopy . TLR4, TLR5 and TLR9 were expressed by gastric epithelium in antrum and corpus of all patients with H . pylori gastritis (n = 14) and with noninflamed gastric mucosa (n = 5) . TLR4 was expressed at the apical and the basolateral pole of the gastric epithelium as well in noninflamed gastric mucosa as in H . pylori gastritis . TLR5 and TLR9 expression in the noninflamed gastric mucosa was identical to that of TLR4 with localization at the apical and the basolateral epithelial pole . However, in H . pylori gastritis TLR5 and TLR9 expression on the gastric epithelium changed to an exclusive basolateral localization without detectable expression at the apical pole . In the human stomach, the gastric epithelium expressed TLR4, TLR5 and TLR9, which gives it the possibility to interact with H . pylori . Furthermore, gastric epithelial TLR4 expression is highly polarized in an apical and a basolateral compartment, whereas TLR5 and TLR9 polarization seems to be a process dynamically influenced by H . pylori infection . This polarized and dynamically regulated gastric epithelial expression of TLRs supports a sentinel role for these receptors in the mucosal immunity to H . pylori. Ying Yong Sheng Tai Xue Bao, 2004 Feb, 15(2), 295 - 8 {Degradation of methyl parathion in soil and Chinese chive by strain DLL-1}; Zhang R et al.; Degradation of methyl parathion in soil and Chinese chive by strain DLL-1 was studied . Usage of methyl parathion at 7.5, 15, and 22.5 kg(a.i.).hm-2 resulted in the average amount of residue of 0.663, 1.270, and 1.901 mg.kg-1 in Chinese chive respectively . The natural degradation rate was 98.94%, 96.44%, and 96.04% corresponding to the 3 levels of usage . The amount of pesticide residue could be significantly decreased through the application of high effective degrading microbial agents . The amount of pesticide residue in Chinese chive and soil was 0.269 and 0.099 mg.kg-1 with the usage of 75 kg.hm-2 of degradation bacterium, which was decreased by 78.82% and 98.68% compared with the control . Increasing the bacterium usage led to the increase of degradation rate . Usage of degradation bacterium more than 75 kg.hm-2 did not increase the degradation rate further . The best time of the application of the degrading microbe was 3 days after the application of the pesticide. Immunity, 2004 May, 20(5), 551 - 62 Dynamics of blood-borne CD8 memory T cell migration in vivo; Klonowski KD et al.; Memory T cells are distributed throughout the body following infection, but the migratory dynamics of the memory pool in vivo is unknown . The ability of circulating microbe-specific memory T cells to populate lymphoid and nonlymphoid tissues was examined using adoptive transfer and parabiosis systems . While migration of memory CD8 T cells to lymph nodes and peritoneal cavity required G(i)-coupled receptor signaling, migration to the spleen, bone marrow, lung, and liver was independent of this pathway . Following parabiosis, memory T cells rapidly equilibrated into the lymphoid tissues, lung, and liver of each parabiont, implying most memory cells were not obligately tissue resident . Equilibration of memory cell populations was delayed in the brain, peritoneal cavity, and intestinal lamina propria, indicating controlled gating for entry into these tissues . In addition, memory cell migration to the lamina propria required beta7 integrins . Thus, the blood-borne T cell pool serves to maintain the homeostasis of tissue-based memory populations. Plant Physiol, 2004 May, 135(1), 47 - 58 Proton-transfer-reaction mass spectrometry as a new tool for real time analysis of root-secreted volatile organic compounds in Arabidopsis; Steeghs M et al.; Plant roots release about 5% to 20% of all photosynthetically-fixed carbon, and as a result create a carbon-rich environment for numerous rhizosphere organisms, including plant pathogens and symbiotic microbes . Although some characterization of root exudates has been achieved, especially of secondary metabolites and proteins, much less is known about volatile organic compounds (VOCs) released by roots . In this communication, we describe a novel approach to exploring these rhizosphere VOCs and their induction by biotic stresses . The VOC formation of Arabidopsis roots was analyzed using proton-transfer-reaction mass spectrometry (PTR-MS), a new technology that allows rapid and real time analysis of most biogenic VOCs without preconcentration or chromatography . Our studies revealed that the major VOCs released and identified by both PTR-MS and gas chromatography-mass spectrometry were either simple metabolites, ethanol, acetaldehyde, acetic acid, ethyl acetate, 2-butanone, 2,3,-butanedione, and acetone, or the monoterpene, 1,8-cineole . Some VOCs were found to be produced constitutively regardless of the treatment; other VOCs were induced specifically as a result of different compatible and noncompatible interactions between microbes and insects and Arabidopsis roots . Compatible interactions of Pseudomonas syringae DC3000 and Diuraphis noxia with Arabidopsis roots resulted in the rapid release of 1,8-cineole, a monoterpene that has not been previously reported in Arabidopsis . Mechanical injuries to Arabidopsis roots did not produce 1,8-cineole nor any C6 wound-VOCs; compatible interactions between Arabidopsis roots and Diuraphis noxia did not produce any wound compounds . This suggests that Arabidopsis roots respond to wounding differently from above-ground plant organs . Trials with incompatible interactions did not reveal a set of compounds that was significantly different compared to the noninfected roots . The PTR-MS method may open the way for functional root VOC analysis that will complement genomic investigations in Arabidopsis. J Biol Chem, 2004 Jul 16, 279(29), 30143 - 9 Epub 2004 May 11. Selective and efficient immunoprecipitation of the disease-associated form of the prion protein can be mediated by nonspecific interactions between monoclonal antibodies and scrapie-associated fibrils; Morel N et al.; Transmissible spongiform encephalopathies are characterized by the accumulation in brain tissues of an abnormal isoform of the prion protein named PrPsc, which is the only direct marker known for transmissible spongiform encephalopathies . Here we show that PrPsc can be specifically immunoprecipitated by using several monoclonal antibodies (mAbs) of various specificities independently of the properties of their binding site (paratope) . These results strongly suggest that a significant proportion of mAbs can interact with PrPsc aggregates through nonspecific paratope-independent interactions allowing selective immunoprecipitation of PrPsc when these mAbs are immobilized on a polydisperse solid phase like microbeads. J Biol Chem, 2004 Jul 23, 279(30), 31010 - 7 Epub 2004 May 11. Drug uptake and modulation of drug resistance in Leishmania by an aquaglyceroporin; Gourbal B et al.; Leishmaniasis is a protozoan parasitic disease that affects 12 million people worldwide . The first line choice for the treatment of this disease is antimonial drugs . In the endemic regions, resistance to this class of drugs is a major impediment to treatment . Microbes often become resistant to drugs by mutation or down-regulation of uptake systems, but the uptake system for the antimonial drugs in Leishmania is unknown . In other organisms, aquaglyceroporins have been shown to facilitate uptake of trivalent metalloids . In this study, we report the identification and characterization of aquaglyceroporins from Leishmania major (LmAQP1) and Leishmania tarentolae (LtAQP1), respectively . These Leishmania proteins have the conserved signature motifs of aquaglyceroporins . Transfection of LmAQP1 into three species of Leishmania, L . tarentolae, Leishmania infantum, and L . major, produced hypersensitivity to both As(III) and Sb(III) in all three strains . Increased production of LmAQP1 was detected by immunoblotting . Drug-resistant parasites with various mutations leading to resistance mechanisms became hypersensitive to both metalloids after expression of LmAQP1 . Increased rates of uptake of As(III) or Sb(III) correlated with metalloid sensitivity of the wild type and drug-resistant transfectants . Transfection of LmAQP1 in a Pentostam-resistant field isolate also sensitized the parasite in the macrophage-associated amastigote form . One allele of LmAQP1 was disrupted in L . major, and the resulting cells became 10-fold more resistant to Sb(III) . This is the first report of the uptake of a metalloid drug by an aquaglyceroporin in Leishmania, suggesting a strategy to reverse resistance in the field. Biol Sci Space, 2003 Dec, 17(4), 298 - 301 Development of an ion microbeam system for irradiating single plant cell{s}; Yokota Y et al.; An ion microbeam system for irradiating single plant cells was developed to analyze exact biological effects of ion beams . Tobacco BY-2 protoplasts were used as a model of single plant cells . Protoplasts were cultured in thin agarose medium on a specially designed irradiation-vessel, which has a CR-39 nuclear track detector (a 100-micro meter thick sheet) . The colony formation rate of unirradiated protoplasts was 22.7 +- 6.7% (mean +- SE of 3 different experiments) after a month of culture . Protoplasts were irradiated with programmed numbers of 18.3 MeV/u carbon ions that had been collimated by a 20-micro mf micro-aperture . After the irradiation, the positions within the protoplasts that were hit with ions were accurately determined by etching the CR-39 sheet in 13.4M KOH solution at 27 centigrade for 9h . The hit rate of the carbon ion microbeam, i.e., the percent of the ion particles that hit the protoplast that they were aimed at, was 56.9 +- 2.4% (mean +- SE of 7 different replications). Spectrochim Acta A Mol Biomol Spectrosc, 2004 May, 60(6), 1349 - 57 Search for EPR markers of the history and origin of the insoluble organic matter in extraterrestrial and terrestrial rocks; Gourier D et al.; The insoluble organic matter (IOM) of three carbonaceous meteorites (Orgueil, Murchison and Tagish Lake meteorites) and three samples of cherts (microcrystalline SiO2 rock) containing microfossils with age ranging between 45 million years and 3.5 billion years is studied by electron paramagnetic resonance (EPR) . The age of the meteorites is that of the solar system (4.6 billion years) . The purpose of this work was to determine the EPR parameters, which allow us to discriminate between biogenic and extra terrestrial origin for the organic matter . Such indicators should be relevant for the controversy regarding the biogenicity of the organic matter in the oldest cheroot (3.5 billion years) and in Martian meteorites containing microbe-like microstructures . The organic matter of meteorites contains a high concentration of diradicaloid moieties characterised by a diamagnetic ground state S = 0 and a thermally accessible triplet state S = 1 . The three meteorites exhibit the same singlet-triplet gap (ST gap) DeltaE approximately 0.1 eV . To the best of our knowledge, such diradicaloids are unknown in insoluble organic matter of terrestrial origin . We have also shown that the EPR linewidth of insoluble organic matter in cherts and coals decrease logarithmically with the age of the organic matter . We conclude from this result that the organic matter in the oldest cherts (3.5 billion years) has the same age as their SiO2 matrix, and is not due to a latter contamination by bacteria, as was recently found in meteoritic samples. J Eukaryot Microbiol, 2004 Mar-Apr, 51(2), 125 - 38 Viral control of phytoplankton populations--a review; Brussaard CP; Phytoplankton population dynamics are the result of imbalances between reproduction and losses . Losses include grazing, sinking, and natural mortality . As the importance of microbes in aquatic ecology has been recognized, so has the potential significance of viruses as mortality agents for phytoplankton . The field of algal virus ecology is steadily changing and advancing as new viruses are isolated and new methods are developed for quantifying the impact of viruses on phytoplankton dynamics and diversity . With this development, evidence is accumulating that viruses can control phytoplankton dynamics through reduction of host populations, or by preventing algal host populations from reaching high levels . The identification of highly specific host ranges of viruses is changing our understanding of population dynamics . Viral-mediated mortality may not only affect algal species succession, but may also affect intraspecies succession . Through cellular lysis, viruses indirectly affect the fluxes of energy, nutrients, and organic matter, especially during algal bloom events when biomass is high . Although the importance of viruses is presently recognized, it is apparent that many aspects of viral-mediated mortality of phytoplankton are still poorly understood . It is imperative that future research addresses the mechanisms that regulate virus infectivity, host resistance, genotype richness, abundance, and the fate of viruses over time and space. Microbiology, 2004 May, 150(Pt 5), 1507 - 18 Induction of Mycobacterium avium growth restriction and inhibition of phagosome-endosome interactions during macrophage activation and apoptosis induction by picolinic acid plus IFNgamma; Pais TF et al.; Treatment of mouse macrophages with picolinic acid (PA) and gamma-interferon (IFNgamma) led to the restriction of Mycobacterium avium proliferation concomitant with the sequential acquisition of metabolic changes typical of apoptosis, mitochondrial depolarization, annexin V staining and caspase activation, over a period of up to 5 days . However, triggering of cell death by ATP, staurosporine or H(2)O(2) failed to affect mycobacterial viability . In contrast to untreated macrophages where extensive interactions between phagosomes and endosomes were observed, phagosomes from treated macrophages lost the ability to acquire endosomal dextran . N-Acetylcysteine was able to revert both the anti-mycobacterial activity of treated macrophages as well as the block in phagosome-endosome interactions . The treatment, however, induced only a minor increase in the acquisition of lysosomal markers, namely Lamp-1, and did not increase to any great extent the acidification of the phagosomes . These data thus suggest that the anti-mycobacterial activity of PA and IFNgamma depends on the interruption of intracellular vesicular trafficking, namely the blocking of acquisition of endosomal material by the microbe. Microbiology, 2004 May, 150(Pt 5), 1261 - 70 Spore morphotypes of Thelohania solenopsae (microsporidia) described microscopically and confirmed by PCR of individual spores microdissected from smears by position ablative laser microbeam microscopy; Sokolova YY et al.; Development of Thelohania solenopsae, a parasite of the red imported fire ant (Solenopsis invicta), until recently was thought to include formation of two types of spores: unicellular meiospores, maturing inside sporophorous vesicles in sets of eight (octospores); and Nosema-like binuclear free spores . Megaspores, discovered in 2001, develop primarily in alates and are morphologically distinct from the two previously known types of spores . The role of megaspores in the T . solenopsae life cycle, as well as their existence, has been questioned . The current research includes light and electron microscopic descriptions of the three major spore morphotypes characteristic of T . solenopsae development . In addition, individual octospores and megaspores were isolated into groups of 8-20 from methanol-fixed and Calcofluor-stained smears of the infected ants for subsequent PCR analysis by the laser pressure catapulting function of a position ablative laser microbeam microscope, a technique applied for the first time to research of microsporidia . The PCR-amplified SSU rDNA nucleotide sequences from octospores and megaspores were identical . This, along with the consistency with which megaspores are detected in infected ants, demonstrates that megaspores are integral to the life cycle of T . solenopsae. Appl Environ Microbiol, 2004 May, 70(5), 3158 - 62 Bacteriophage-based genetic system for selection of nonsplicing inteins; Cann IK et al.; A genetic selection system that detects splicing and nonsplicing activities of inteins was developed based on the ability to rescue a T4 phage strain with a conditionally inactive DNA polymerase . This phage defect can be complemented by expression of plasmid-encoded phage RB69 DNA polymerase . Insertion of an intein gene into the active site of the RB69 DNA polymerase gene renders polymerase activity and phage viability dependent on protein splicing . The effectiveness of the system was tested by screening for thermosensitive splicing mutants . Development of genetic systems with the potential of identifying protein splicing inhibitors is a first step towards controlling proliferation of pathogenic microbes harboring inteins in essential proteins. Appl Environ Microbiol, 2004 May, 70(5), 3103 - 9 Negative cross-communication among wheat rhizosphere bacteria: effect on antibiotic production by the biological control bacterium Pseudomonas aureofaciens 30-84; Morello JE et al.; Phenazine antibiotic production in the biological control bacterium Pseudomonas aureofaciens 30-84 is regulated in part via the PhzR/PhzI N-acyl homoserine lactone (AHL) system . Previous work showed that a subpopulation of the wheat rhizosphere community positively affected phenazine gene expression in strain 30-84 via AHL signals (E . A . Pierson, D . W . Wood, J . A . Cannon, F . M . Blachere, and L . S . Pierson III, Mol . Plant-Microbe Interact . 11:1078-1084, 1998) . In the present work, a second subpopulation, one that negatively affected phenazine gene expression, was identified from this rhizosphere community . Strain 30-84 grown in conditioned medium (CM) from several strains produced lower levels of phenazines (1.5- to 9.3-fold) than control when grown in CM from the strain 30-84I(1)/I(2) . Growth of the phzB::lacZ reporter strain 30-84Z in this CM resulted in decreased lacZ expression (4.3- to 9.2-fold) compared to growth of the control strain in CM, indicating that inhibition of phzB occurred at the level of gene expression . Preliminary chemical and biological characterizations suggested that these signals, unlike other identified negative signals, were not extractable in ethyl acetate . Introduction of extra copies of phzR and phzI, but not phzI alone, in trans into strain 30-84Z reduced the negative effect on phzB::lacZ expression . The presence of negative-signal-producing strains in a mixture with strain 30-84 reduced strain 30-84's ability to inhibit the take-all disease pathogen in vitro . Together, the results from the previous work on the positive-signal subpopulation and the present work on the negative-signal subpopulation suggest that cross-communication among members of the rhizosphere community and strain 30-84 may control secondary metabolite production and pathogen inhibition. Appl Environ Microbiol, 2004 May, 70(5), 3082 - 90 Novel forms of structural integration between microbes and a hydrothermal vent gastropod from the Indian Ocean; Goffredi SK et al.; Here we describe novel forms of structural integration between endo- and episymbiotic microbes and an unusual new species of snail from hydrothermal vents in the Indian Ocean . The snail houses a dense population of gamma-proteobacteria within the cells of its greatly enlarged esophageal gland . This tissue setting differs from that of all other vent mollusks, which harbor sulfur-oxidizing endosymbionts in their gills . The significantly reduced digestive tract, the isotopic signatures of the snail tissues, and the presence of internal bacteria suggest a dependence on chemoautotrophy for nutrition . Most notably, this snail is unique in having a dense coat of mineralized scales covering the sides of its foot, a feature seen in no other living metazoan . The scales are coated with iron sulfides (pyrite and greigite) and heavily colonized by epsilon- and delta-proteobacteria, likely participating in mineralization of the sclerites . This novel metazoan-microbial collaboration illustrates the great potential of organismal adaptation in chemically and physically challenging deep-sea environments. Biochemistry, 2004 May 11, 43(18), 5159 - 69 Structural comparison of MTA phosphorylase and MTA/AdoHcy nucleosidase explains substrate preferences and identifies regions exploitable for inhibitor design; Lee JE et al.; The development of new and effective antiprotozoal drugs has been a difficult challenge because of the close similarity of the metabolic pathways between microbial and mammalian systems . 5'-Methylthioadenosine/S-adenosylhomocysteine (MTA/AdoHcy) nucleosidase is thought to be an ideal target for therapeutic drug design as the enzyme is present in many microbes but not in mammals . MTA/AdoHcy nucleosidase (MTAN) irreversibly depurinates MTA or AdoHcy to form adenine and the corresponding thioribose . The inhibition of MTAN leads to a buildup of toxic byproducts that affect various microbial pathways such as quorum sensing, biological methylation, polyamine biosynthesis, and methionine recycling . The design of nucleosidase-specific inhibitors is complicated by its structural similarity to the human MTA phosphorylase (MTAP) . The crystal structures of human MTAP complexed with formycin A and 5'-methylthiotubercidin have been solved to 2.0 and 2.1 A resolution, respectively . Comparisons of the MTAP and MTAN inhibitor complexes reveal size and electrostatic potential differences in the purine, ribose, and 5'-alkylthio binding sites, which account for the substrate specificity and reactions catalyzed . In addition, the differences between the two enzymes have allowed the identification of exploitable regions that can be targeted for the development of high-affinity nucleosidase-specific inhibitors . Sequence alignments of Escherichia coli MTAN, human MTAP, and plant MTA nucleosidases also reveal potential structural changes to the 5'-alkylthio binding site that account for the substrate preference of plant MTA nucleosidases. Micron, 2004, 35(6), 431 - 9 Differential-aperture X-ray structural microscopy: a submicron-resolution three-dimensional probe of local microstructure and strain; Yang W et al.; A recently developed differential-aperture X-ray microscopy (DAXM) technique provides local structure and crystallographic orientation with submicron spatial resolution in three-dimensions; it further provides angular precision of approximately 0.01 degrees and local elastic strain with an accuracy of approximately 1.0 x 10(-4) using microbeams from high brilliance third generation synchrotron X-ray sources . DAXM is a powerful tool for inter- and intra-granular studies of lattice distortions and lattice rotations on mesoscopic length scales of tenths of microns to hundreds of microns that are largely above the range of traditional electron microscopy probes . Nondestructive, point-to-point, spatially resolved measurements of local lattice orientations in bulk materials provide direct information on geometrically necessary dislocation density distributions through measurements of the lattice curvature in plastically deformed materials . This paper reviews the DAXM measurement technique and discusses recent demonstrations of DAXM capabilities for measurements of microtexture, local elastic strain, and plastic deformation microstructure. J Endotoxin Res, 2004, 10(2), 120 - 4 TLR-independent pattern recognition receptors and anti-inflammatory mechanisms; Fraser IP et al.; Pattern recognition receptors recognize molecular patterns associated with the surfaces of microbes and apoptotic cells . These receptors act alone and in concert to bind, phagocytose, and transduce cellular signals derived from these molecular patterns . The outcome of these interactions is dependent on the nature of the ligands, and upon the nature and combination of the ligated receptors . Whereas much attention has been focused on the properties and activities of the Toll-like receptors (TLRs) in this process, many other pattern recognition molecules have been described . Here we review some of these non-TLR receptors and their ligands, and focus attention on the mannose binding lectin, a humoral pattern recognition molecule . In addition, we describe how recognition of apopotic cells via pattern recognition receptors appears to result in responses that differ from those elicited by microbial ligands. AIDS Res Hum Retroviruses, 2004 Mar, 20(3), 327 - 35 Interaction of mannose-binding lectin with HIV type 1 is sufficient for virus opsonization but not neutralization; Ying H et al.; Mannose-binding lectin (MBL), a microbe-recognition protein in serum, binds to high mannose glycans on HIV-1 gp120 and has been reported to neutralize the cell line-adapted strain HIV(IIIB) . Because HIV primary isolates (PI) are generally more resistant to neutralization by antibodies and considering that PI are produced in primary cells that could alter the number of high mannose glycans on HIV relative to cell lines, we assessed the ability to MBL to neutralize HIV PI . MBL at concentrations up to 50 microg/ml mediated relatively little neutralization (<20%) of HIV PI infection of peripheral blood mononuclear cells (PBMCs) . MBL-neutralizing activity was slightly higher for cell line-adapted HIV infection of the H9 T cell line (up to 64% at 50 microg/ml) . However, this effect was specific for H9 cells since MBL did not neutralize cell line-adapted virus infection of PBMCs, HIV PI infection of the GHOST cell line, or VSV pseudotyped with HIV gp160 from cell line-derived virus or PI . In contrast to its low activity in neutralization assays, MBL efficiently bound infectious HIV PI and opsonized HIV PI for uptake by monocytic cells . These results show that both PI and cell line-adapted HIV, despite binding of MBL, are relatively resistant to neutralization by levels of MBL normally present in serum . However, binding and opsonization of HIV by MBL may alter virus trafficking and viral-antigen presentation during HIV infection. Clin Chim Acta, 2004 May, 343(1-2), 85 - 92 Differentiation of human umbilical cord blood CD133+ stem cells towards myelo-monocytic lineage; Ruzicka K et al.; BACKGROUND: Characterisation of stem cells by flow cytometry, their expansion and differentiation are presently of major interest for cell engineering as the basis of a therapeutic concept for transplantation . Haematopoietic stem cells (HSC) express CD34, the adhesion structure which binds 2L-selectin, CD117, a receptor for stem cell factor (SCF; c-kit ligand), and CD133, a transmembrane protein belonging to the family of mucoproteins . METHODS: The aim of the present investigation was the systematic investigation of proliferation and differentiation characteristics of umbilical cord blood stem cells (UCBSC) isolated by an immmunomagnetic separation system using CD133 antibody-coated microbeads and to evaluate the effects of different sera and various concentrations, as well as the effects of IL-3 and IL-6 on total cell expansion and differentiation of isolated CD133+ cells . Differentiation patterns were measured by flow cytometry . RESULTS: After the immmunomagnetic separation the yield of CD133+ cells was 0.45+/-0.17 x 10(6) cells/ml; the purity of isolated CD133+ cells was 95.79+/-1.86% . The majority of CD133+ cells coexpressed CD117 . The most pronounced expansion during cultivation of 2 weeks was achieved in media supplemented with 12.5% horse serum plus 12.5% fetal calf serum (FCS) with stem cell factor and interleukine 3; the fold-expansion was 16.67+/-6.20 . During the cultivation period, UCBSC were constantly loosing stem cell markers and differentiated towards myelo-monocyte lineage (granulocytes and/or monocytes) . CONCLUSIONS: These in vitro results demonstrate that thorough investigation of various cultivation conditions is needed for successful expansion and differentiation of stem cells towards different lineages to be used therapeutically for replacement of damaged cells. Blood, 2004 Aug 15, 104(4), 1066 - 74 Epub 2004 Apr 27. Tuning the volume of the immune response: strength and persistence of stimulation determine migration and cytokine secretion of dendritic cells; Luft T et al.; Migration to lymph nodes and secretion of cytokines are critical functions of mature dendritic cells (DCs); however, these 2 functions are not necessarily linked . This is the first report showing that quantitative differences in identical signaling pathways determine DC migration and cytokine secretion . Using different polymerized forms of CD40 ligand, we demonstrate that the strength and persistence of CD40 signaling can induce either function . Induction of monocyte-derived DC (MoDC) migration required a weak and transient CD40 signal, whereas strong and persistent CD40 signaling blocked migration and biased toward cytokine secretion . In contrast to MoDCs, CD40 activation of CD1c+ peripheral blood DCs (PBDCs) induced a nonpersistent, intracellular signaling profile resulting in migratory-type DCs unable to secrete interleukin-12p70 (IL-12p70) . Extracellular signal-regulated kinase 1/2 (ERK1/2) and p38K activation synergistically mediated cytokine secretion, whereas migration was enhanced by p38K activation but reduced by persistent ERK1/2 activity . This model of signal strength and persistence also applied when stimulating DCs with intact microbes . Thus, a novel concept emerges in which the type of immune response induced by DCs is tuned by the strength and persistence of DC activating signals. Anal Biochem, 2004 May 15, 328(2), 113 - 22 Microbead-based electrochemical immunoassay with interdigitated array electrodes; Thomas JH et al.; The objective of this study was to develop a sensitive and miniaturized immunoassay by coupling a microbead-based immunoassay with an interdigitated array (IDA) electrode . An IDA electrode amplifies the signal by recycling an electrochemically redox-reversible molecule . The microfabricated platinum electrodes had 25 pairs of electrodes with 1.6-microm gaps and 2.4-microm widths . An enzyme-labeled sandwich immunoassay on paramagnetic microbeads with mouse IgG as the analyte and beta-galactosidase as the enzyme label was used as the model system . beta-Galactosidase converted p-aminophenyl beta-D-galactopyranoside to p-aminophenol (PAP) . This enzyme reaction was measured continuously by positioning the microbeads near the electrode surface with a magnet . Electrochemical recycling occurred with PAP oxidation to p-quinone imine (PQI) at +290 mV followed by PQI reduction to PAP at -300 mV vs Ag/AgCl . Dual-electrode detection amplified the signal fourfold compared to single-electrode detection, and the recycling efficiency reached 87% . A calibration curve of PAP concentration vs anodic current was linear between 10(-4) and 10(-6)M . A signal from 1000 beads in a 20-microL drop was detectable and the immunoassay was complete within 10 min with a detection limit of 3.5x10(-15)mol mouse IgG. Diabetes, 2004 May, 53(5), 1285 - 92 From blood monocytes to adipose tissue-resident macrophages: induction of diapedesis by human mature adipocytes; Curat CA et al.; Obesity has been suggested to be a low-grade systemic inflammatory state, therefore we studied the interaction between human adipocytes and monocytes via adipose tissue (AT)-derived capillary endothelium . Cells composing the stroma-vascular fraction (SVF) of human ATs were characterized by fluorescence-activated cell sorter (FACS) analysis and two cell subsets (resident macrophages and endothelial cells {ECs}) were isolated using antibody-coupled microbeads . Media conditioned by mature adipocytes maintained in fibrin gels were applied to AT-derived ECs . Thereafter, the expression of endothelial adhesion molecules was analyzed as well as the adhesion and transmigration of human monocytes . FACS analysis showed that 11% of the SVF is composed of CD14(+)/CD31(+) cells, characterized as resident macrophages . A positive correlation was found between the BMI and the percentage of resident macrophages, suggesting that fat tissue growth is associated with a recruitment of blood monocytes . Incubation of AT-derived ECs with adipocyte-conditioned medium resulted in the upregulation of EC adhesion molecules and the increased chemotaxis of blood monocytes, an effect mimicked by recombinant human leptin . These results indicate that adipokines, such as leptin, activate ECs, leading to an enhanced diapedesis of blood monocytes, and suggesting that fat mass growth might be linked to inflammatory processes. Vet Clin North Am Small Anim Pract, 2004 May, 34(3), 611 - 22 Matrix metalloproteinase inhibition in corneal ulceration; Brooks DE et al.; The primary objective of current treatment strategies for infectious keratitis is to sterilize the ulcer as rapidly as possible with topically administered antibiotics . Ulcerative processes can proceed in some cases, despite the absence of microbes, as a result of remaining corneal and tear film MMPs . Combining antibiotic therapy with MMP inhibitors can speed corneal healing, because MMPs play an important role in corneal ulceration and stromal liquefaction . MMPs from the rabbit, horse, and human being are inhibited by metal-binding agents EDTA, NAC, and doxycycline as well as by the serum antiprotease alpha2-macroglobulin . It is not yet certain which proteinase inhibitor has the most favorable therapeutic index for clinical use, although we prefer serum because of its effects on multiple types of proteinases . The MMP inhibitors do have significant therapeutic promise in the treatment of corneal ulceration. Cell Biol Int, 2004, 28(4), 293 - 8 Backward chromosome movement in crane-fly spermatocytes after UV microbeam irradiation of the interzone and a kinetochore; Wong R et al.; Single anaphase chromosomes (in crane-fly spermatocytes) moved backwards after double irradiations with an ultraviolet light (UV) microbeam, first of the interzone and then of a kinetochore: the chromosome irradiated at the kinetochore moved backwards rapidly, across the equator and into the other half-spindle . High irradiation doses at the kinetochore were required to induce backward movement . Single irradiations of kinetochores or interzones were ineffective in inducing backward movements. Biomaterials, 2004 Sep, 25(21), 5155 - 62 Biodegradability of poly (2-hydroxyethyl methacrylate) in the presence of the J774.2 macrophage cell line; Mabilleau G et al.; The degradation of cross-linked and linear poly(2-hydroxyethyl methacrylate) (pHEMA), was examined in vitro with J774.2 cells . pHEMA microbeads were prepared with both types of polymers . Only cells in contact with the microbeads increased their production of lysosomal enzymes (TRAcP and ANAE) and released large amounts of reactive oxygen species with both types of pHEMA microbeads . Electron microscopy showed that macrophages were able to erode the surface of linear pHEMA but unable to erode the surface of the cross-linked polymer . Cells appeared wrapped by the linear pHEMA surface, but those cultured on the cross-linked polymer were only laying at the surface . After cell culture, the surface roughness of pHEMA slices was observed by atomic force microscopy (AFM) . There was a significant increase in roughness (R(a)) of the surface of linear pHEMA slices cultured with J774.2 cells whereas no difference in R(a) between the surface of cross-linked pHEMA slices could be measured . AFM image of the hydrated materials were done: the surface of linear pHEMA swelled considerably in saline whereas the hydrated cross-linked polymer did not differ from the air-dried appearance . In conclusion, linear pHEMA swells in biological fluids, activates macrophages in close contact with the polymer and can be progressively eroded. Anal Bioanal Chem, 2004 Jun, 379(3), 419 - 26 Epub 2004 Apr 23. Biomagnetic separation of Escherichia coli by use of anion-exchange beads: measurement and modeling of the kinetics of cell-bead interactions; Deponte S et al.; Analyses of food-borne pathogens are of great importance in order to minimize the risk of infection for customers . These analyses should be as fast as possible . Any detection method requires enrichment and quantitative analysis of the enriched microbes . Conventional enrichment methods, which take several days, need to be replaced by faster techniques such as biomagnetic separation (BMS) . This technique involves the use of paramagnetic microspheres coated with ligands that have special affinity to the microbes that have to be detected . In the studies reported here, enrichment experiments by BMS were carried out using the non-pathogenic E . coli DSM 498 as a model strain and beads coated with a polyethylenimine (PEI) anion-exchange material . The results show that the number of cells separated, as a proportion of the total, was positively correlated with the bead concentration and the length of the period they were mixed together . In addition, a mathematical model, based on the rate of impact between two different sorts of particles, was developed to describe the proportion of separated cells as a function of incubation time and the concentration, size and density of the beads and cells . This is the first mathematical description of cell-bead interactions to be based on well-understood physicochemical principles . The model was confirmed by separation experiments in which the concentration of beads and the incubation period were varied . The developed model enables optimization of the amount of beads added and the reaction period necessary for complete cell separation and thus minimization of costs in BMS. J Immunol, 2004 May 1, 172(9), 5304 - 12 CD1d1 displayed on cell size beads identifies and enriches an NK cell population negatively regulated by CD1d1; Huang MM et al.; NK cells destroy microbe-infected cells while sparing healthy cells, and are controlled, in part, by inhibitory receptors specific for class I Ag-presenting molecules . CD1d1, a beta(2)-microglobulin-associated class I-like molecule, binds glycolipids and stimulates NKT cells . We previously demonstrated that target cell lysis by IL-2-activated mouse NK cells is inhibited by target cell expression of CD1d1, suggesting that IL-2-activated NK cells may express a CD1d1-specific inhibitory receptor . We now report that a significant subset of mouse IL-2-activated NK cells specifically binds cell size beads displaying either naturally expressed or recombinant CD1d1 . In contrast, although tetramers of soluble recombinant CD1d1 loaded with alpha-galactosylceramide identify NKT cells, binding of this reagent to resting or IL-2-activated NK cells was undetectable, even with activated NK cells sorted with CD1d1 beads . Cytotoxicity by the CD1d1 bead-separated NK subset was strongly inhibited by CD1d1, compared with the NK cell subset not bound to CD1d1 beads . An Ab that blocks NKT cell recognition of CD1d1 also reverses CD1d1 inhibition of NK lysis, suggesting that TCRs of NKT cells and NK inhibitory receptor(s) may interact with a similar site on CD1d1 . These results provide direct evidence for a physical interaction of NK cells with CD1d1, mediated by a functional, CD1d1-specific low-affinity inhibitory NK receptor . Display of ligands on cell size beads to maximize multivalent interaction may offer an alternative approach to examine NK cell receptor-ligand interactions, particularly those of lower expression and/or lower affinity/avidity that may go undetected using tetrameric reagents. Plant Biol (Stuttg), 2004 Jan-Feb, 6(1), 91 - 9 Compatible and incompetent Paxillus involutus isolates for ectomycorrhiza formation in vitro with poplar (Populus x canescens) differ in H2O2 production; Gafur A et al.; Isolates of Paxillus involutus (Batsch) Fr . collected from different hosts and environmental conditions were screened for their ability to form ectomycorrhizal symbiosis with hybrid poplar P . x canescens (= Populus tremula L . x P . alba) in vitro . The ability to form ectomycorrhiza varied between the fungal isolates and was not correlated with the growth rate of the fungi on agar-based medium . The isolate MAJ, which was capable of mycorrhiza synthesis under axenic conditions, and the incompetent isolate NAU were