Annu Rev Phytopathol, 2000, 38, 365 - 396 NEMATODE PARASITISM GENES; Davis EL et al.; The ability of nematodes to live on plant hosts involves multiple parasitism genes . The most pronounced morphological adaptations of nematodes for plant parasitism include a hollow, protrusible stylet (feeding spear) connected to three enlarged esophageal gland cells that express products that are secreted into plant tissues through the stylet . Reverse genetic and expressed sequence tag (EST) approaches are being used to discover the parasitism genes expressed in nematode esophageal gland cells . Some genes cloned from root-knot (Meloidogyne spp.) and cyst (Heterodera and Globodera spp.) nematodes have homologues reported in genomic analyses of Caenorhabditis elegans and animal-parasitic nematodes . To date, however, the candidate parasitism genes endogenous to the esophageal glands of plant nematodes (such as the ss-1,4-endoglucanases) have their greatest similarity to microbial genes, prompting speculation that genes for plant parasitism by nematodes may have been acquired by horizontal gene transfer. Annu Rev Phytopathol, 1999, 37, 427 - 446 BIOCONTROL WITHIN THE CONTEXT OF SOIL MICROBIAL COMMUNITIES: A Substrate-Dependent Phenomenon; Hoitink H et al.; Broad spectrum biological control of diseases caused by soilborne plant pathogens such as Pythium, Phytophthora, and Rhizoctonia solani requires the introduction into or presence of edaphic sources of organic nutrients in soil for sustenance of biocontrol agents . The decomposition level of organic matter critically affects the composition of bacterial taxa as well as the populations and activities of biocontrol agents . Competition, antibiosis, parasitism, and systemic induced resistance are all affected . Highly stabilized sources of Sphagnum peat consistently fail to support sustained biological control, even when inoculated with biocontrol agents . Composts, on the other hand, can serve as an ideal food base for biocontrol agents and offer an opportunity to introduce and establish specific biocontrol agents into soils, which in turn leads to sustained biological control based on the activities of microbial communities. Annu Rev Phytopathol, 1999, 37, 127 - 149 EFFECTS OF PLANTS ON NEMATODE COMMUNITY STRUCTURE; Yeates G; Plant-related inputs provide the resources for nematode communities . Sampling of nematode communities must be on appropriate temporal and spatial scales . Size, feeding types, food or host specificity, and chronology allow over 200 nematode species to coexist in a district . Relationships between nematode functional groups and ecological processes regulating decomposition processes have been found in field experiments . Pulse-labeling experiments have shown root-feeding nematodes to increase the flow of carbon from roots to soil microbial biomass . Soil texture is related to suitability for cropping and affects nematode communities through crop-specific infestations . Nematode diversity tends to be greatest in ecosystems with least disturbance, and bacterial-feeding nematodes make the greatest contribution to the decomposer food web in more intensively managed ecosystems . Indices of the nematode fauna reflect changes in the nematode community; these changes reflect soil and ecological processes . Understanding the role of nematodes in these processes is the key to understanding of the relationship between plants and soil nematode communities. J Clin Endocrinol Metab, 2001 Nov, 86(11), 5383 - 8 GH strongly affects serum concentrations of mannan-binding lectin: evidence for a new IGF-I independent immunomodulatory effect of GH; Hansen TK et al.; Studies in animals and humans indicate that GH and IGF-I modulate immune function . Recently, it was reported that GH therapy increased the mortality in critically ill patients . The excessive mortality was almost entirely attributable to septic shock or multiorgan failure, suggesting that a GH-induced modulation of immune function was involved . In the present study, we examined whether GH or IGF-I influences the serum concentrations of mannan-binding lectin (MBL) . MBL is a plasma protein of the innate immune system that initiates the complement cascade and activates inflammation after binding to carbohydrate structures on microbial surfaces . We performed a cross-over study of 16 healthy men examined during a control period, and during treatment with either GH or IGF-I for 6 d . The levels of MBL were more than doubled during GH treatment, whereas no changes were observed in the IGF-I group or during the control period (P < 0.001) . IGF-I levels were elevated similarly during treatment with GH and IGF-I . Subsequently, we studied 30 healthy persons and 25 GH-deficient (GHD) patients randomized to treatment with GH or placebo in a double-blinded manner, and further included samples from 23 patients with active acromegaly examined before and after treatment with octreotide or the GH-receptor antagonist pegvisomant for 3 months . Baseline concentrations of MBL were lower in GHD patients and higher in acromegalic patients than in healthy subjects (P < 0.02) . Treatment with GH doubled the MBL concentrations in healthy subjects and almost quadrupled the concentrations in GHD patients; whereas in acromegalic patients, the levels of MBL were reduced to approximately two thirds of the initial values during treatment with octreotide or pegvisomant . Our results demonstrate that treatment with GH, but not IGF-I, significantly increases MBL concentrations . The clinical consequences of this new link between the endocrine and the immune system remain to be elucidated. J Dent Educ, 2001 Oct, 65(10), 1096 - 101 Salivary enhancement: current status and future therapies; Atkinson JC et al.; Saliva provides the principal protective milieu for teeth by modulating oral microbial ecosystems and reversing the initial phases of caries development . Patients with inadequate salivary function are at increased risk for dental decay . Therefore, it is likely that therapies that increase overall fluid output of these individuals will reverse early carious lesions . The most common causes of salivary dysfunction are medication usage, Sjogren's syndrome, and damage of salivary parenchyma during therapeutic irradiation . For patients with remaining functional acinar tissue, treatment with the parasypathomimetic secretogogues pilocarpine and Cevimeline may provide relief . However, these medications do not benefit all patients . The possibilities of using gene therapy and tissue engineering to develop treatments for those with severe salivary dysfunction are discussed. Clin Exp Med, 2001 Jun, 1(2), 113 - 9 Bacterial translocation from defunctionalized rat small bowel; Stenback A et al.; Bacterial translocation from the intestine may cause severe infectious complications in a number of clinical situations, including the short bowel syndrome and after small bowel transplantation . The aim of the present study was to develop a simplified model for the study of bacterial translocation from a defunctionalized intestine . An ileal segment from untreated or cyclosporine-treated rats was exteriorized as a Thiry-Vella loop . After 1, 3 . or 7 days, bacterial translocation and distribution of immunocompetent cells were assessed . The data obtained were compared with data from animals subjected to intestinal transplantation . Translocation to the mesenteric lymph nodes was detected in 60% of the Thiry-Vella loop animals on day 1 . in 100% on day 3, and in 83% on day 7: concomitantly, the number of macrophages and T-cells in the mesenteric lymph nodes increased from day I until day 7 . The degree of bacterial translocation on days 3 and 7 in animals with a Thiry-Vella loop was comparable with that observed 7 days after intestinal transplantation . Furthermore, treatment with cyclosporine A enhanced the number of translocating bacteria . In the model presented here bacterial translocation occurs from the small bowel to the mesenteric lymph nodes . The model offers possibilities to study the mechanisms and immunological phenomena associated with microbial translocation. J Contam Hydrol, 2001 Nov, 52(1-4), 57 - 83 Predicting natural attenuation of xylene in groundwater using a numerical model; Schafer W; The aquifer beneath an abandoned refinery in the Lower Rhine area, Germany, was contaminated with a number of different mineral oil products . Groundwater sampling in the area around the former xylene plant revealed that a xylene plume had developed in the underlying groundwater, and moreover, that there is strong evidence for in situ microbial xylene degradation with oxygen, nitrate, sulfate and ferric iron as electron acceptors . In order to prevent further xylene spreading, three pumping wells extracting contaminated water were installed downgradient of the spill zone . The numerical reactive transport code Transport Biochemisty Chemistry (TBC) was applied to this situation to quantify the relation of microbial degradation to xylene removal by the pumping wells . It could be shown that the unamended in situ degradation was an appreciable xylene removal process that contributed to about one-third to the total xylene removal (degradation plus extraction) . A further objective of the model application was to predict xylene spreading under regional flow conditions, i.e . without operation of the three pumping wells, to consider the possible effects of natural xylene attenuation . To accomplish this, the model calibrated for the situation with operating wells was transferred to the hydraulic situation of regional flow while retaining the parameters of the biochemical model . It turned out that the xylene plume that is expected to develop downgradient of the source area will be limited to an extension of not more than 1000 m . An interesting feature of the simulations results was that xylene degradation under iron-reducing conditions, which was of minor importance for the situation with operating pumping wells, becomes the dominant degradation mechanism under regional flow conditions . Moreover, iron reduction will be the key process in controlling plume evolution . The model application illustrates that multi-species reactive transport models are needed to adequately transfer reactive processes from one hydraulic situation to another, while single species models are not suited for this predictive task. Chemosphere, 2001 Nov, 45(6-7), 849 - 56 Microbial dechlorination of three PCB congeners in river sediment; Chang BV et al.; We investigated the potential for the anaerobic degradation of three PCB congeners (2,3,5,6-CB, 2,3,4,5-CB, and 2,3,4,5,6-CB) in sediments collected from five monitoring sites along the Keelung River in northern Taiwan . Optimal conditions for congener dechlorination were 30 degrees C and pH 7.0 . Intermediate 2,3,4,5-CB products were identified as 2,3,5-CB, 2,4,5-CB, and 2,5-CB . Intermediate 2,3,4,5,6-CB products were identified as 2,3,5,6-CB, 2,3,6-CB, and 2,5-CB . For 2,3,5,6-CB, intermediate products were identified as 2,3,6-CB and 2,5-CB . Dechlorination rates for PCB congeners were observed as (fastest to slowest): 2, 3, 4-CB > 2, 3, 4, 5-CB > 2, 3, 4, 5, 6-CB > 2, 3, 5, 6-CB > 2, 2', 3, 3', 4, 4'-CB > 2, 2', 4, 4' 6, 6'-CB > 2, 2', 3, 4, 4', 5, 5'-CB > 2, 2', 3, 3', 4, 4', 5, 5'-CB . Rates decreased for mixtures of the eight congeners . Dechlorination rates for the three primary congeners under different reducing conditions occurred in the order of (fastest to slowest): methanogenic condition > sulfate-reducing condition > nitrate-reducing condition . Under methanogenic and sulfate-reducing conditions, dechlorination rates were enhanced by the addition of lactate, pyruvate, or acetate, but delayed by the addition of manganese oxide, or ferric chloride . Under nitrate-reducing condition, dechlorination rates were delayed by the addition of lactate, pyruvate, acetate, manganese oxide or ferric chloride . Treatment with such microbial inhibitors as bromoethanesulfonic acid (BESA) or molybdate revealed that methanogen and sulfate-reducing bacteria were involved in the dechlorination of these three PCB congeners. Chemosphere, 2001 Nov, 45(6-7), 775 - 82 Mineralisation studies of 14C-labelled metsulfuron-methyl, tribenuron-methyl, chlorsulfuron and thifensulfuron-methyl in one Danish soil and groundwater sediment profile; Andersen SM et al.; Bacterial mineralisation of four sulfonylurea herbicides at 20 microg kg(-1) in a sandy soil from nine different depths in a sandy soil horizon (5-780 cm) was investigated in laboratory studies . Metsulfuron-methyl, chlorsulfuron, and tribenuron-methyl were 14C-labelled in the sulfonamide ring, while thifensulfuron-methyl was labelled in the thiophene ring . The highest mineralised amount in 126 days was observed for metsulfuron-methyl (40%) followed by tribenuron-methyl (25%), and thifensulfuron-methyl (11%) . Chlorsulfuron showed low mineralisation in all the soils tested (<4%) . Mineralisation of the herbicides metsulfuron-methyl and tribenuron-methyl varied according to soil depth (upper profile: 5-70 cm, and lower profile: 165-780 cm) and were proven faster in soil taken from depths 5-7 and 30-35 cm, and slower in depths 45-50 and 70-75 cm . Mineralisation was absent in the lower profile (165-780 cm) . As an indicator of microbial activity bacterial counts were taken at the experimental start; these counts grouped in three levels: highest in the surface layer (5-7 cm), slightly lower in the depths 30-75 cm, and lowest in the lower profile (165-780 cm) . Residual concentrations of metsulfuron-methyl correlated to the accumulated amount mineralised, with high residual concentrations in soil showing low mineralisation . Also chlorsulfuron showed high residual concentrations with increasing depth in the upper profile, but the relatively high dissipation at 30-35 cm and lower one at 45-50 cm could not be related with the lack of mineralisation . This shows that hydrolysis occurs, but mineralisation of the chloro-substituted sulfonamide is restricted . Tribenuron-methyl and thifensulfuron-methyl could not be detected due to interference with other compounds. J Biol Regul Homeost Agents, 2001 Jul-Sep, 15(3), 257 - 64 Antiviral activity and anergy of gammadeltaT lymphocytes in cord blood and immuno-compromised host; Montesano C et al.; Gammadelta T lymphocytes recognize nonpeptidic microbial antigens without MHC restriction and display both lytic and proliferative responses to human immunodeficiency virus (HIV)-infected cells . This innate recognition involves both T Cell Receptor (TCR) and NK-receptor mediated signalling through non-peptidic metabolites and HLA class I down-regulation . We observed that HLA-masking and nonpeptidic phosphoantigens induce the expression of CD25 and CD69 activation markers on the surface of gammadelta T cells . Interestingly, CD94+ cell depletion by magnetic beads showed that the expression of this antigen is essential for Vdelta2 T cell activation by HLA-masking . Moreover, both phosphoantigen-stimulation and in vitro HIV infection resulted in marked Vgamma9Vdelta2 T cell expansion, whereas HLA-masking was unable to induce proliferative responses . Finally, we observed a relevant hyporesponsiveness to non-peptidic antigens in HIV-infected persons and in cord blood cells from healthy donors when compared to adult PBMC from uninfected donors . Altogether, the reduced ability to naturally recognize the infected cells may contribute to HIV-disease progression and may facilitate maternal transmission of HIV infections. J Biol Regul Homeost Agents, 2001 Jul-Sep, 15(3), 249 - 56 Immunity to glycolipid antigens in microbial infections; De Libero G et al.; T cells recognize ligands of different chemical structures . Recently, it has become clear that also self glycosphingolipids and bacterial lipoglycans may act as T cell stimulatory ligands . This type of antigen recognition is restricted by the non-polymorphic CD1 molecules, which have a structure resembling that of classical MHC molecules . Glycolipids insert their hydrophobic lipid tails in two pockets below the antigen-binding groove and position their hydrophilic heads on the external part of CD1 molecules . TCR interacts with these carbohydrates and discriminates their structural variations . Glycolipid-specific T cells may provide protection during bacterial and parasite infection probably with different mechanisms: by secreting pro-inflammatory lymphokines, by the direct killing of infected target cells, and by helping specific B cells in Ig production . Lipoglycans represent excellent candidates for new anti-microbial vaccines due to their wide distribution in the microbial world and their structural composition which does not change and thus cannot give rise to escape mutants . Moreover, these vaccines might induce anti-microbial protective T cell responses in the whole population due to the non-polymorphic nature of CD1 presenting molecules. Mikrobiol Z, 2001 Jul-Aug, 63(4), 15 - 9 {Peculiarities of structure-function organization of microbial groups of soil contaminated by cement dust}; Stefurak VP; Long-term contamination of the forest soil by the cement dust leads to disturbances of stability of natural microbial groups, changes their quantitative and qualitative composition, results in substitution of some microbial associations by other ones . The intensive contamination of the soil by the effluents of cement integrated works, inhibits the intensity of nitrogen fixation processes and decay of the forest litter, development of micromycetes, results in the decrease of the length of mycelium and its biomass. Vet Clin North Am Food Anim Pract, 2001 Nov, 17(3), 621 - 33, viii Immunomodulators for prevention and treatment of infectious diseases in food-producing animals; Blecha F; The goal of immunomodulation in food-producing animals is to regulate immunity for the benefit of the animal and production efficiency . Immunomodulators are substances that exert this control and include cytokines, pharmaceuticals, microbial products, nutraceuticals, and traditional medicinal plants . Although treatment and prevention of infectious diseases are the most common reasons to use immunomodulators, other conditions, such as amelioration of stress-induced immunosuppression, maturation of the neonate's developing immune response, and strategies to reduce the metabolic cost of eliciting an immune response also are well suited for immunomodulation . Continued discovery of new immune regulators and increased understanding of immunity in food-producing animals will ensure new opportunities for the use of immunomodulators in food-producing animals. Vet Clin North Am Food Anim Pract, 2001 Nov, 17(3), 585 - 97, vii New technology for improved vaccine safety and efficacy; Roth JA et al.; Nearly all of the 2000 vaccines presently licensed by the US Department of Agriculture for veterinary use in the United States are conventional vaccines containing either killed or modified live whole bacteria or viruses . Recent advances in molecular biology, immunology, microbiology, and genetics and in understanding microbial pathogenesis have led to the development of a wide variety of new approaches for developing safer and more effective vaccines . This article briefly describes these new technologies and their potential advantages and disadvantages as compared with conventional killed and modified live vaccines. J Allergy Clin Immunol, 2001 Nov, 108(5), 847 - 54 Exposure to endotoxin decreases the risk of atopic eczema in infancy: a cohort study; Gehring U et al.; BACKGROUND: Previous studies have shown a protective effect of early exposure to cats and dogs on the development of atopic eczema, asthma, allergic rhinitis, and atopic sensitization in later life . In particular, a higher microbial exposure to endotoxin in early childhood might contribute to this effect . OBJECTIVE: We examined the associations between bacterial endotoxin in house dust and atopic eczema, infections, and wheezing during the first year of life in an ongoing birth cohort study (LISA) . METHODS: Data of 1884 term and normal-weight neonates with complete information on exposure to biocontaminants and confounding variables were analyzed . House dust from the mothers' and the children's mattresses was sampled 3 months after birth . Endotoxin content was quantified by using a chromogenic kinetic limulus amoebocyte lysate test . RESULTS: During the first 6 months of life, the risk of atopic eczema was significantly decreased by endotoxin exposure in dust from mothers' mattresses in the fifth quintile (odds ratio {OR}, 0.50; 95% CI, 0.28-0.88), whereas the risk was increased for respiratory infections (OR, 1.69; 95% CI, 1.25-2.28) and cough with respiratory infection, bronchitis, or both (OR, 1.73; 95% CI, 1.28-2.33) . The risk of wheezing was also significantly increased during the first 6 months of life (OR, 2.37; 95% CI, 1.40-4.03) . For the entire first year of life, these associations attenuated, except for the risk of wheezing, which remained significant (OR, 1.60; 95% CI, 1.10-2.30) . CONCLUSION: Our findings support the hygiene hypothesis that exposure to high concentrations of endotoxin very early in life might protect against the development of atopic eczema within the first 6 months of life, along with an increased prevalence of nonspecific respiratory diseases. J Allergy Clin Immunol, 2001 Nov, 108(5), 688 - 96 Multistep navigation of Langerhans/dendritic cells in and out of the skin; Jakob T et al.; Langerhans cells (LCs) are specialized antigen-presenting cells that reside in the epidermis as sentinels of the immune system . LCs constantly monitor the epidermal microenvironment by taking up antigen and processing it into fragments that can be recognized by cells of the adaptive immune response . Because of their unique migratory ability, LCs can transport antigen from the epidermis to regional lymph nodes, where they can initiate systemic immune responses . The mechanisms of LC trafficking thus seem to be of particular relevance for the induction and maintenance of cutaneous immunity . LCs or their putative precursors express surface molecules that allow them to home to skin and localize in the epidermis for prolonged periods of time . Tissue injury, microbial infection, and other perturbants of epidermal homeostasis (eg, contact allergens) provide danger signals, leading to a local production of proinflammatory cytokines that induce LC mobilization to the lymphoid tissue . At the same time, signals are generated that recruit LC precursors into the skin to maintain the epidermal LC population . Distinct pairs of chemokines and their receptors control the migration from blood to epidermis and from there to the regional lymphatics . In addition, trafficking is controlled at the level of cell adhesion, where LCs downregulate some adhesion molecules to exit the epidermis and upregulate others to migrate across the extracellular matrix and home to T-cell areas of regional lymphoid tissue . The improved understanding of mechanisms that regulate LC trafficking might offer new opportunities for therapeutic interventions to suppress, stimulate, or deviate cutaneous immune responses. J Biotechnol, 2002 Jan 18, 92(3), 259 - 66 Synthesis of a novel macrolactone by lipase-catalyzed intra-esterification of hydroxy-fatty acid in organic media; Gargouri M et al.; The unsaturations and groups bound to the ring and to the lateral chain of lactones give a large diversity in this class of molecules . In this work we produced enzymatically a macrolactone in organic media . The substrate used was a hydroxy-fatty acid: (+)-coriolic acid and the enzymes tested were free or immobilized microbial lipases . The immobilized lipase from Candida antarctica seems to be the most adequate catalyst offering a high reaction yield . The intra-esterification was studied as a function of temperature and type of solvent . Higher yields were obtained when using diisopropyl-ether at 35 degrees C . This reaction, involving an alcohol group on an internal position on the carbon chain of the substrate hydroxy-acid, produces an original lactone: 13S-octadeca-(9Z,11E)-dienolide . The product was purified and characterized using (1)H nuclear magnetic resonance spectroscopy, mass spectrometry and infrared spectroscopy. Respir Res, 2001, 2(3), 129 - 32 Epub 2001 Apr 02. The coming-of-age of the hygiene hypothesis; Martinez FD; The hygiene hypothesis, as originally proposed, postulated an inverse relation between the incidence of infectious diseases in early life and the subsequent development of allergies and asthma . New evidence from epidemiological, biological and genetic studies has significantly enlarged the scope of the hypothesis . It now appears probable that environmental 'danger' signals regulate the pattern of immune responses in early life . Microbial burden in general, and not any single acute infectious illness, is the main source of these signals . The latter interact with a sensitive and complex receptor system, and genetic variations in this receptor system may be an important determinant of inherited susceptibility to asthma and allergies. J Anim Physiol Anim Nutr (Berl), 2001 Feb, 85(1-2), 9 - 21 Small intestinal digestibility of microbial and endogenous amino acids in dairy cows; Larsen M et al.; The small intestinal digestibility of microbial amino acids and the apparent re-absorption of endogenous amino acids were estimated in three ruminal, duodenal and ileal fistulated lactating dairy cows . The cows were assigned to a 3 x 3 Latin square and fed diets low in amino acids, composed of straw, starch, molasses and urea . The treatments were three straw to concentrate ratios . The digestibilities and re-absorptions were estimated from duodenal and ileal flows of amino acids from feed, microbial and endogenous sources . The duodenal distribution of amino acids between different origins was determined by the difference method and by the amino acid profile method . The ileal distribution was estimated by a simple method where the feed fraction was estimated by the mobile bag method, the endogenous fraction as the water soluble fraction and the microbial fraction as the rest . In ileal samples, 8.0 +/- 1.1, 52.2 +/- 2.9 and 39.8 +/- 2.6% of total amino acid nitrogen (AAN) were of feed, microbial and endogenous origin, respectively, compared with 5.1 +/- 0.9, 61.6 +/- 6.6 and 32.7 +/- 6.9% in duodenal samples . The small intestinal digestibility of microbial AAN was estimated to be 75.1 +/- 1.8% and the apparent re-absorption of endogenous AAN to be 62.3 +/- 11.1%. Phytochemistry, 2001 Nov, 58(6), 929 - 33 Biocatalytic chlorination of aromatic hydrocarbons by chloroperoxidase of Caldariomyces fumago; Vazquez-Duhalt R et al.; Chloroperoxidase from Caldariomyces fumago was able to chlorinate 17 of 20 aromatic hydrocarbons assayed in the presence of hydrogen peroxide and chloride ions . Reaction rates varied from 0.6 min(-1) for naphthalene to 758 min(-1) for 9-methylanthracene . Mono-, di- and tri-chlorinated compounds were obtained from the chloroperoxidase-mediated reaction on aromatic compounds . Dichloroacenaphthene, trichloroacenaphthene, 9,10-dichloroanthracene, chloropyrene, dichloropyrene, dichlorobiphenylene and trichlorobiphenylene were identified by mass spectral analyses as products from acenaphthene, anthracene, pyrene and biophenylene respectively . Polycyclic aromatic hydrocarbons with 5 and 6 aromatic rings were also substrates for the chloroperoxidase reaction . The importance of the microbial chlorination of aromatic pollutants and its potential environmental impact are discussed. Can J Microbiol, 2001 Sep, 47(9), 877 - 82 Rapid identification of Escherichia coli microcin J25 producing strains using polymerase chain reaction and colony blot hybridization; Duarte M et al.; To screen, isolate, and characterize bacterial populations producing microcin J25, we report here two rapid, reliable, and sensitive methods, using polymerase chain reaction and colony blot hybridization with a digoxigenin-labelled probe . A sample of 26 Escherichia coli strains isolated from poultry intestinal contents was evaluated to detect the sequence of mcjA, the gene encoding the MccJ25 precursor . The two molecular techniques were compared with the commonly used cross-immunity tests . They generate accurate data with no obvious cross-reactions with other microcins . The results display that the producers of MccJ25 were widely distributed in the poultry intestinal habitat . The applications of these molecular methods will be useful in future studies of microcinogenic populations, and thus contribute to understand the relationships within the complex intestinal microbial ecosystem. Curr Opin Genet Dev, 2001 Dec, 11(6), 620 - 6 Detection of lateral gene transfer among microbial genomes; Ragan MA; An increasingly comprehensive assessment is being developed of the extent and potential significance of lateral gene transfer among microbial genomes . Genomic sequences can be identified as being of putatively lateral origin by their unexpected phyletic distribution, atypical sequence composition, differential presence or absence in closely related genomes, or incongruent phylogenetic trees . These complementary approaches sometimes yield inconsistent results . Not only more data but also quantitative models and simulations are needed urgently. FEMS Microbiol Lett, 2001 Oct 16, 204(1), 1 - 7 Predicting the emergence of resistance to antifungal drugs; Cowen LE; The emergence of antifungal drug resistance is inevitable . Here I discuss antibiotic resistance in the context of the adaptive potential of fungi and I propose an approach to predicting the evolution of antifungal resistance using experimental evolution of DNA sequences and microbial populations . Prediction is based on determination of evolutionary potential at two levels, the gene and the genome . At the level of the gene, evolutionary potential depends on the sequence space of candidate resistance genes defined by the fitness effects of all possible mutations in all possible combinations . At the level of the genome, evolutionary potential depends on the adaptive landscape defined by the fitness effects of all possible interactions among alleles constituting the genotype. Chemosphere, 2001 Nov, 45(4-5), 445 - 51 Microbial ecotoxicity and mutagenicity of 1-hydroxypyrene and its photoproducts; Hwang HM et al.; 1-Hydroxypyrene (1-HP) is a carcinogenic and slightly water-soluble polycyclic aromatic hydrocarbon . Ecotoxicity and mutagenicity of 1-HP and its photoproducts, and the effect of Mn2+ and Cu2+ on their mutagenicity were measured with microbial assay in this study . The assay includes spread plate counting, direct counting, microbial mineralization of 14C-UL-D-glucose and Mutatox Test . At the concentration examined (0.8 microM), the photoproducts (after 1.5 h solar irradiation) of 1-HP inhibited microbial glucose mineralization activity (by 64%) after microbial assemblages of a local reservoir site were exposed for 1 day . However, heterotrophic bacteria were able to utilize 1-HP photoproducts as the growth substrates and increase viability counts by up to 4.75-folds . 1-HP exhibited positive response to Mutatox Test in both direct medium and S-9 medium, with the lowest observable effective concentration of 0.625 microM in the test with direct medium . After photolysis, 1-HP decreased its mutagenicity . Mn2+ (312.5 microM-5 mM) and Cu2+ (6.25-100 microM) themselves are not mutagenic . However, addition of the metal ions before or after photolysis modifies the light readings of 1-HP during the test . Therefore, presence of metal ions could affect the genotoxicity of 1-HP in aquatic environments, depending on timing of the addition. Adv Immunol, 2001, 79, 55 - 92 Regulation of interleukin-12 production in antigen-presenting cells; Ma X et al.; Interleukin-12 is a cytokine produced by antigen-presenting cells that is essential for host defense against intracellular microbial infection and control of malignancy by virtue of its ability to stimulate both innate and adaptive immune effector cells . The immune potentiating capacity of IL-12 and its mandatory requirement in host defense predispose it to rigorous regulation . The time, localization, and magnitude of IL-12 production during an immune response strongly influence the type, extent, and, ultimately, the fate of the response . Disturbance of this evolutionarily maintained "balance of power" frequently leads to immunologic disorders . This article reviews the intricate pathways that have been uncovered in which IL-12 production is modulated by numerous pathogens and immunological regulators . The understanding of IL-12 regulation in physiological settings will undoubtedly lend valuable support to the design of therapeutic applications of IL-12. Appl Environ Microbiol, 2001 Nov, 67(11), 5343 - 8 Diversity and detection of nitrate assimilation genes in marine bacteria; Allen AE et al.; A PCR approach was used to construct a database of nasA genes (called narB genes in cyanobacteria) and to detect the genetic potential for heterotrophic bacterial nitrate utilization in marine environments . A nasA-specific PCR primer set that could be used to selectively amplify the nasA gene from heterotrophic bacteria was designed . Using seawater DNA extracts obtained from microbial communities in the South Atlantic Bight, the Barents Sea, and the North Pacific Gyre, we PCR amplified and sequenced nasA genes . Our results indicate that several groups of heterotrophic bacterial nasA genes are common and widely distributed in oceanic environments. Biosens Bioelectron, 2001 Dec, 16(9-12), 695 - 9 The extremely rapid oligonucleotide hybridization and high throughput detection of microbial gene sequences using fluorescence polarization; Tsuruoka M et al.; The hybridization of oligonucleotide sequences complementary to the genes of Shiga toxins (verotoxins) types 1 and 2 of enterohaemorrhagic Escherichia coli (EHEC) and human hepatitis C virus (HCV) was monitored using fluorescence polarization under the reaction condition of high salt concentration (0.8 M NaCl), which was optimized to obtain a higher rate of hybridization . The time courses of hybridization of fluorescently labeled oligomers (probe DNAs) with the amplified DNA or RNA of the genes were recorded . Two methods, the asymmetric PCR and NASBA, were used to amplify the genetic DNA of Shiga toxins and that of RNA in HCV, respectively . Probe DNA sequences were designed which hybridized extremely rapidly with amplicons of the genes of Shiga toxins types 1 and 2 and that of HCV . In the cases using the three different DNA probes, the hybridization was 90% complete in about 1 min, considerably faster than that of the 3 min reported previously . The rapidity of this hybridization could not be explained by the melting temperature or the G+C content of the probe sequences but its relationship with high order structure of the single stranded DNA or RNA of the amplicons in the solution was strongly suggested. J Am Diet Assoc, 2001 Oct, 101(10), 1194 - 8 A survey of the use of low microbial diets in pediatric bone marrow transplant programs; French MR et al.; A survey was used to determine the use of low microbial diets for pediatric bone marrow transplantation patients at hospitals in Canada and the northwestern United States . Five out of 7 hospitals responding to the survey provided a low microbial diet to this population to reduce the potential risk posed by food pathogens . Two hospitals prepared their low microbial diet in a separate kitchen using aseptic techniques . One hospital provided a diet consisting of well-cooked foods or foods containing a minimum number of pathogen-forming units . Another hospital focused on safe food-handling guidelines, avoiding foods associated with foodborne illness . A final hospital reported using a modified house diet that excluded fresh fruits and vegetables . Various guidelines were used to determine when to initiate and discontinue the low microbial diet . These guidelines included criteria such as a specific day relative to transplantation and a patient's absolute neutrophil count . Results indicate that most hospitals acknowledge the potential for food to cause infection in patients with compromised immune systems by imposing dietary restrictions to limit pathogen exposure. Int Immunol, 2001 Nov, 13(11), 1391 - 404 Lipopolysaccharide and CpG DNA synergize for tumor necrosis factor-alpha production through activation of NF-kappaB; Yi AK et al.; Unmethylated CpG motifs in bacterial DNA (CpG DNA) activate host innate immune responses synergistically with some other microbial products, such as endotoxins, and may contribute to disease pathogenesis through excessive production of proinflammatory cytokines . Because monocyte-derived tumor necrosis factor (TNF)-alpha is an important mediator of disease, we investigated whether CpG DNA and lipopolysaccharide (LPS) synergize for inducing TNF-alpha biosynthesis . CpG DNA and LPS synergistically induce TNF-alpha production in RAW264.7 cells and J774 cells through activation of NF-kappaB . Furthermore, transient transfection with a super-repressive mutant of IkappaBalpha (IkappaBalpha-AA) demonstrated that NF-kappaB plays a critical role in CpG DNA-mediated TNF-alpha expression . Like NF-kappaB activation, CpG DNA-induced activation of mitogen-activated protein kinases (MAPK) regulates TNF-alpha production . Both extracellular receptor kinase (ERK) and p38 can regulate TNF-alpha gene transcription induced by CpG DNA . Although CpG DNA at the higher concentration slightly enhanced LPS-mediated phosphorylation of ERK, it did not alter the LPS-mediated activation of c-Jun N-terminal kinase and p38 . In addition, CpG DNA showed little or no enhancement of LPS-mediated AP-1 activation . These results suggest that CpG DNA- and LPS-mediated signals converge at or above the level of NF-kappaB and ERK, and that there are distinct, as well as common, signaling pathways which are utilized by both CpG DNA and LPS for activating various transcription factors and MAPK. Inorg Chem, 1999 Feb 8, 38(3), 449 - 454 Electrochemical Behavior of the Fe(III) Complexes of the Cyclic Hydroxamate Siderophores Alcaligin and Desferrioxamine E; Spasojevic I et al.; The redox behavior of Fe(III) complexes of the cyclic hydroxamate siderophores alcaligin and desferrioxamine E was investigated by cyclic voltammetry . The limiting, pH independent redox potential (E(1/2) vs NHE) is -446 mV for alcaligin above pH 9 and -477 mV for ferrioxamine E above pH 7.5 . At lower pH values, the redox potential for both complexes shifts positive, with a loss of voltammetric reversibility which is interpreted to be the consequence of a secondary dissociation of Fe(II) from the reduced form of the complexes . These observations are of biological importance, since they suggest the possibility of a reductive mechanism in microbial cells which utilize these siderophores to acquire Fe . For comparison purposes, cyclic voltammograms were obtained for Fe(III) complexes with trihydroxamic acids of cyclic (ferrioxamine E) and linear (ferrioxamine B) structures, with dihydroxamic acids of cyclic (alcaligin) and linear (rhodotorulic and sebacic acids) structures, and with monohydroxamic acids (acetohydroxamic and N-methylacetohydroxamic acids) at identical conditions . The observed redox potentials allow us to estimate the overall stability constants for fully coordinated Fe(II) complexes as log beta(II)(Fe(2)alcaligin(3)) = 24.6 and log beta(II)(ferrioxamine E) = 12.1 . A linear correlation between E(1/2) and pM was found, and the basis for this relationship is discussed in terms of structural (denticity and cyclic/acyclic) and electronic differences among the {alkyl-NOH-CO-alkyl} type of hydroxamic acid ligands studied. Contraception, 2001 Jun, 63(6), 335 - 42 Effect of vaginally administered (Ala(8,13,18))-magainin II amide on the morphology of implantation stage endometrium in the rhesus monkey (Macaca mulatta); Ghosh D et al.; Intravaginal administration of an anti-microbial agent, (Ala(8,13,18))-magainin II amide, during blastocyst implantation inhibits pregnancy establishment in a dose-related manner in the rhesus monkey (Macaca mulatta) . In the present study, mated female rhesus monkeys were vaginally inserted with tampons containing vehicle (Group 1; n = 5) and test agent (magainin, 0.5 mg/animal; Group 2; n = 6) on cycle day 20 . Endometrial tissue samples were collected on Cycle Day 24 from all monkeys and processed for morphometric and ultrastructural analysis . Concentrations of estradiol-17beta, progesterone, and chorionic gonadotrophin in peripheral circulation were determined, which revealed that two monkeys in Group 1 were pregnant while no animals were pregnant in Group 2 . Endometrial morphology, however, revealed histologic evidence of pregnancy in three out of the six magainin-treated animals . It appears that intra-vaginal administration of magainin II amide had a marginal effect on the implantation stage endometrium and the initiation of the implantation process in the rhesus monkey. Inorg Chem, 1998 Dec 28, 37(26), 6630 - 6637 A Preorganized Siderophore: Thermodynamic and Structural Characterization of Alcaligin and Bisucaberin, Microbial Macrocyclic Dihydroxamate Chelating Agents(1); Hou Z et al.; The iron coordination chemistry of two macrocyclic dihydroxamate siderophores, alcaligin (AG) and bisucaberin (BR), has been investigated thermodynamically and structurally . Alcaligin is a siderophore of freshwater bacteria as well as mammalian pathogens, including the bacterium that causes whooping cough in humans, while bisucaberin, a structural analogue of alcaligin, is produced by marine bacteria . Both alcaligin and bisucaberin form 1:1 ferric complexes (FeL(+)) in acidic conditions and 2:3 ferric complexes (Fe(2)L(3)) at and above neutral pH . The stability constants of these macrocyclic dihydroxamate siderophores differ significantly from that of rhodotorulic acid (RA), a linear dihydroxamate siderophore . Notably, K(FeL) of alcaligin is 32 times greater than that of rhodotorulic acid, while the subsequent stepwise formation constant for Fe(2)L(3) is 3 times less . The Fe(III) complexes of alcaligin are stereospecific; the absolute configuration of the Fe(2)L(3) complex (circular dichroism and X-ray structure) is Lambda . The structure of the Fe(2)L(3) alcaligin complex is a topological alternative to the triple-helicate structure of the rhodotorulic complex Fe(2)(RA)(3) . The structures of the free ligand and the bisbidentate ligand in the FeL complex are essentially identical, indicating that alcaligin is highly preorganized for metal ion binding . This explains the difference in K(FeL) between alcaligin and rhodotorulic acid, as well as explaining the monobridged topology of the Fe(2)L(3) alcaligin complex . The protonation constants (log K(a1) and log K(a2)) are 9.42(5) and 8.61(1) for alcaligin and 9.49(2) and 8.76(3) for bisucaberin . The stepwise formation constants of the Fe(III) complexes (log K(ML) and log K(M)()2(L)()3) are 23.5(2) and 17.7(2) for alcaligin and 23.5(5) and 17.2(5) for bisucaberin . The overall formation constants (log beta(230)) of alcaligin and bisucaberin are 64.7(1) and 64.3(1) . The solution chemistry of Fe(III) and alcaligin was further investigated at a lower ligand to metal ratio (1:1) . At high pH, a novel 2:2 ferric bis-&mgr;-oxo-bridged complex of alcalagin forms (Fe(2)L(2)O(2)(2)(-)) with a log beta(22)(-)(4) of 16.7(2) . This species exhibits behavior consistent with an iron bis-&mgr;-oxo complex, including antiferromagnetic coupling . Crystal data: Fe(2)(AG)(3).25H(2)O crystallizes in the orthorhombic space group P2(1)2(1)2(1) with a =13.3374(4) A, b = 16.1879(5) A, c = 37.886(1) A, V = 8179.7(4), Z = 4 . For 5512 reflections with F(o)(2) > 3sigma(F(o)(2)) the final R (R(w)) = 0.053(0.068). Cytokine, 2001 Oct 7, 16(1), 1 - 9 Differential response of the murine IL-12 p35 gene to lipopolysaccharide compared with interferon-gamma and CD40 ligation; Vaidyanathan H et al.; Expression of the heterodimeric cytokine interleukin-(IL-)12 is induced by pattern recognition receptors responding to microbial stimuli such as lipopolysaccharide (LPS) and products of the immune system such as interferon-gamma (IFN-gamma) and CD40L . The formation of bioactive IL-12 requires equimolar synthesis of p35 and p40 subunits . However, p35 expression limits the amount of IL-12 formed . Transcription of the gene for the p35 subunit of IL-12 initiates within the first exon, an alternate first exon (exon 1a), or second exon . Here we show that LPS and IFN-gamma/CD40 ligation increase the amount of total p35 mRNA in splenic adherent cells (SAC) to a similar extent . However, the exon 1 transcript was a smaller fraction of total p35 mRNA in IFN-gamma/CD40-stimulated cells than in unstimulated or LPS-stimulated cells . Despite comparable levels of total p35 mRNA, LPS-induced p35 exon 1 transcripts led to significantly more bioactive IL-12 from SAC than IFN-gamma/CD40-induced exon 1a/exon 2 transcripts as measured by ELISA . The data suggest that LPS-inducible p35 synthesis from exon 1 p35 transcripts leads to greater amount of bioactive IL-12 than IFN-gamma/CD40-induced p35 expression from alternate p35 exon 1a/exon 2 transcripts . J Dent Res, 2001 Aug, 80(8), 1695 - 9 Polymorphisms of the interleukin-1 gene family, oral microbial pathogens, and smoking in adult periodontitis; Laine ML et al.; Interleukin (IL)-1alpha, IL-1beta, and IL-1ra contribute to regulation of the inflammatory response in periodontal tissues . We aimed to investigate the distribution of polymorphisms in the IL-1 gene family among periodontitis patients and controls, taking into account smoking and microbiology as additional variables . Fifty-three non-smoking and 52 smoking patients with severe adult periodontitis and 53 controls were genotyped for bi-allelic IL-1A(-889), IL-1B(-3954), and a penta-allelic 86-bp VNTR IL-1RN gene polymorphisms . The presence of Porphyromonas gingivalis and Actinobacillus actinomycetemcomitans was established by culture techniques . We found a higher frequency of allele 2 carriage in IL-1A, IL-1B, and IL-1RN in periodontitis patients who were non-smokers and in whom P . gingivalis and A . actinomycetemcomitans could not be detected (42.1% vs . 11.3% in controls; P = 0.0068; OR 5.7, 95% CI: 1.6-19.8) . Our results provide evidence that polymorphisms in genes of the IL-1 family are associated with severe adult periodontitis in the absence of other risk factors tested in this patient population. Scand J Infect Dis, 2001, 33(9), 673 - 80 Molecular diagnosis of infective endocarditis--a new Duke's criterion; Millar B et al.; The molecular approach of PCR amplification of specific gene targets and universal loci for bacteria (16S rRNA) and fungi (18S, 28S and 5.8S rRNA) and subsequent sequencing was used to identify the possible causal microbial agent(s) in blood culture (47 patients) and heart valve material (30 patients) from patients with suspected infective endocarditis (IE) . Culture and molecular results were analysed with respect to the patients' clinical background and the Duke Criteria . The findings demonstrated that: (i) all patients who were definite or possible cases were positive by PCR, even patients whose blood culture and valve material were culture-negative; and (ii) all patients who were rejected as having IE were also negative by PCR, with the exception of 1 patient who had bacteraemia from another source and 5 patients whose blood culture material was believed to contain an environmental contaminant . Direct molecular identification of the aetiological agents responsible for IE from blood culture material may enable specific treatment to commence at an earlier stage of the disease and hence reduce the need for valve replacement . Such a molecular approach may aid in the diagnosis of IE and should therefore be included as an additional major criterion in the Duke's classification scheme. Biotechnol Bioeng, 2001 Nov 20, 75(4), 469 - 74 Using ATP bioluminescence technique for monitoring microbial activity in sludge; Chu CP et al.; This study demonstrates, for the first time, that the presence of suspended solids in waste-activated sludge interferes with adenosine triphosphate (ATP) bioluminescence tests . The sludge subject to acid/alkaline treatment represented the test sample . Without consideration of the effect of solid concentrations, one would erroneously estimate the density levels of heterotrophic bacteria in the sludge using ATP data . A light blockage model was proposed to evaluate the luminescence reading without the interference of suspended solids . Respir Res, 2000, 1(2), 67 - 72 Epub 2000 Aug 15. Nitric oxide: a pro-inflammatory mediator in lung disease? van der Vliet A, Eiserich JP, Cross CE. Inflammatory diseases of the respiratory tract are commonly associated with elevated production of nitric oxide (NO*) and increased indices of NO* -dependent oxidative stress . Although NO* is known to have anti-microbial, anti-inflammatory and anti-oxidant properties, various lines of evidence support the contribution of NO* to lung injury in several disease models . On the basis of biochemical evidence, it is often presumed that such NO* -dependent oxidations are due to the formation of the oxidant peroxynitrite, although alternative mechanisms involving the phagocyte-derived heme proteins myeloperoxidase and eosinophil peroxidase might be operative during conditions of inflammation . Because of the overwhelming literature on NO* generation and activities in the respiratory tract, it would be beyond the scope of this commentary to review this area comprehensively . Instead, it focuses on recent evidence and concepts of the presumed contribution of NO* to inflammatory diseases of the lung. J Org Chem, 1996 Apr 19, 61(8), 2845 - 2852 Total Synthesis of Natural PI-091, a New Platelet Aggregation Inhibitor of Microbial Origin; Shiraki R et al.; The total synthesis of a new platelet aggregation-inhibiting gamma-lactam PI-091 (1) gave a 1:1 diastereomeric mixture at the gamma-ketal carbon . The high-yielding aldol reaction of an appropriately protected 1,3,4-trihydroxy-4-methyldecan-2-one 42, prepared from D-glucose, with the kinetically generated enolate of 3-methyl-2-butanone provided 43 . The resulting diastereomeric mixture of the aldol adduct 43 was converted to a 2,4-alkylated furan 45 via an intramolecular ketalization followed by dehydration . The addition of a singlet oxygen to the alpha-trimethylsilylated furan 48derived from 45 under photochemical conditions efficiently provided an alpha,gamma-dialkylated gamma-hydroxy gamma-lactone 47 . The transformation of methyl ketal 52 prepared from 47 into gamma-hydroxy gamma-lactam 53 was achieved by exposure to liquid ammonia in MeOH . The total synthesis of 1 was achieved from 52 through the Dess-Martin periodinane oxidation of the secondary hydroxy group in the side chain . The present total synthesis revealed that the stereogenic carbon center in the side chain in natural 1 is S. Inorg Chem, 1996 Mar 13, 35(6), 1659 - 1666 Chemical and Biological Studies of Dichloro(2-((dimethylamino)methyl)phenyl)gold(III); Parish RV et al.; Several new organogold(III) derivatives of the type {AuX(2)(damp)} (damp = o-C(6)H(4)CH(2)NMe(2)) have been prepared {X = CN, SCN, dtc, or X(2) = tm; dtc = R(2)NCS(2) (R = Me (dmtc) or Et (detc)); tm = SCH(CO(2))CH(2)CO(2)Na} together with {AuCl(tpca)(damp)}Cl (tpca = o-Ph(2)PC(6)H(4)CO(2)H), {Au(dtc)(damp)}Y (Y = Cl, BPh(4)) and K{Au(CN)(3)(damp)} . The (13)C NMR spectra of these and previous derivatives have been fully assigned . In {Au(dtc)(2)(damp)} and K{Au(CN)(3)(damp)}, the damp ligand is coordinated only through carbon, as shown by X-ray crystallography and/or NMR . {Au(detc)(2)(damp)} has space group C2/c, with a = 29.884(4) A, b = 13.446(2) A, c = 12.401(2) A, beta = 99.45(3)(o), V = 4915 A(3), Z = 8, and R = 0.057 for 1918 reflections . The damp and one detc ligand are monodentate, the other detc is bidentate; in solution, the complex shows dynamic behavior, with the detc ligands appearing equivalent . The crystal structure of {Au(dmtc)(damp)}BPh(4) {Pna2(1), a = 26.149(5) A, b = 11.250(2) A, c = 11.921(2) A, V = 3507 A(3), Z = 4, R = 0.073, 1772 reflections} shows both ligands to be bidentate in the cation, but the two Au-S distances are nonequivalent . The crystal structure of {Au(tm)(damp)} has also been determined {P2(1)/n, a = 18.267(7) A, b = 9.618(3) A, c = 18.938(4) A, beta = 113.45(3)(o), V = 3053 A(3), Z = 8, R = 0.079, 1389 reflections} . The tm is bound through sulfur and the carboxyl group which allows five-membered ring formation . In all three structures, the trans-influence of the sigma-bonded aryl group is apparent . {AuCl(2)(damp)} has been tested in vitroagainst a range of microbial strains and several human tumor lines, where it displays differential cytotoxicity similar to that of cisplatin . Against the ZR-75-1 human tumor xenograft, both {AuCl(2)(damp)} and cisplatin showed limited activity. Nature . 1984 Dec 20-27;312(5996):686. Genetic pesticides: Monsanto goes ahead with trials; Beardsley T; KIE: The Monsanto Company will soon notify the Environmental Protection Agency (EPA) that it plans to conduct the first field test of a genetically-engineered microbial pesticide, thereby becoming the first company to break with the convention whereby private corporations have voluntarily sought approval for genetic engineering experiments from the Recombinant DNA Advisory Committee (RAC) of the National Institutes of Health (NIH) . It is assumed that Monsanto's decision was influenced by a preliminary legal injunction blocking NIH approval of such field trials without a formal environmental assessment . EPA will allow tests, after 90 days' notice, if it raises no objections to the protocol . Although EPA will not formally call on RAC to examine the protocol, an agency spokesperson said there is "total agreement" between EPA and RAC on what data must be included . Crit Rev Immunol, 2001, 21(1-3), 121 - 31 Peripheral nonresponsiveness to orally administered soluble protein antigens; Nagler-Anderson C et al.; The presentation of soluble model food antigens to the intestinal immune system typically induces antigen-specific systemic nonresponsiveness . Yet, the gut-associated lymphoid tissue (GALT) must launch an effective attack against potentially invasive pathogens even as it avoids mounting a response to innocuous food antigens . Although the mechanism by which the GALT is able to recognize and respond to these different forms of antigen is not clear, recent studies have shown that, initially, both tolerogenic and immunogenic forms of orally administered antigen elicit transient T-cell activation and proliferation . The unique microenvironment of the GALT plays a central role in determining whether functional T-cell anergy or adaptive immunity is the ultimate response . Administration of model food proteins with adjuvants (microbial products that activate the innate immune system) induces a productive immune response to this normally tolerogenic form of antigen . Recent work from our laboratory has shown that an ongoing enteric infection can itself act as an adjuvant and prime for a response to an orally administered soluble protein antigen. Crit Rev Immunol, 2001, 21(1-3), 1 - 27 On the initial trigger of myasthenia gravis and suppression of the disease by antibodies against the MHC peptide region involved in the presentation of a pathogenic T-cell epitope; Atassi MZ et al.; Myasthenia gravis (MG) is a disabling autoimmune disease caused by autoantibodies (auto-Abs) against the self-acetylcholine receptor (AChR) . Although a great deal of information is known about the molecular and cellular parameters of the disease, its initial trigger, however, is not known . To study the possibility of the involvement of microbial antigens that mimic AChR in triggering MG, we have searched the microbial proteins in the data bank for regions that are similar in structure to the regions of human (h) AChR alpha chain recognized by auto-Abs in MG patients . Hundreds of candidate structures on a large number of bacterial and viral proteins were identified . To test the feasibility of the idea, we synthesized four microbial regions similar to each of the major autodeterminants of hAChR (alpha12-27, alpha111-126, alpha122-138, alpha182-198) and investigated their ability to bind auto-Abs in MG and normal sera controls . It was found that MG sera potentially recognized a significant number of these microbial regions . The results indicate that in some MG cases, immune responses to microbial antigens may cross-react with self-antigen (in this case hAChR) and could constitute initial triggers of the disease . Although anti-AChR Abs directly contribute to the degradation of AChR at the neuromuscular junctions, autoreactive T cells provide help to B cells that synthesize anti-AChR auto-Abs . To cause MG, T cells must recognize the pathogenic epitopes in the context of MHC class II molecules related to MG . The ability to regulate AChR presentation (hence AChR-reactive T-cell activation) could form the basis of an effective strategy for the control of autoimmunity in MG by selectively inhibiting the function of the Ir gene loci linked to disease susceptibility . An animal model of MG (experimental autoimmune MG, EAMG) can be induced in C57BL/6 (B6, H-2b) mice by immunization with Torpedo californica (t) AChR . A mutant mouse of B6, B6.C-H-2bm12 (bm12), which has three amino acid changes (at residues 67, 70, and 71) in the I-A beta(b) subunit, is resistant to EAMG development . Recently, we showed that region 62-76 of I-A beta(b), which contains the above residues, is involved in the binding to a pathogenic T-cell epitope within peptide t alpha146-162 . We have prepared several monoclonal antibodies (mAbs) against peptide I-A beta(b)62-76, which are highly cross-reactive with I-A(b) molecules . These mAbs inhibited in vitro the proliferation of disease-related T cells of B6 specific to tAChR peptide t alpha146-162 . Passive transfer of these mAbs suppressed the occurrence of clinical EAMG, which was accompanied by lower T-cell and Ab responses to tAChR . The results indicated that blocking disease-related MHC by targeting a disease-associated region on MHC molecules could be an effective, straightforward, and feasible strategy for immunointervention in MG. Prog Nucleic Acid Res Mol Biol, 2001, 70, 233 - 89 Nonribosomal biosynthesis of microbial chromopeptides; Keller U et al.; Nonribosomal chromopeptides and mixed chromopeptide-polyketides contain aromatic or heteroaromatic side groups which are important recognition elements for interaction with cellular targets such as DNA and proteins, resulting in the biological activities of these natural products . In the chromopeptide lactones and arylpeptide-siderophores from bacteria, the chromophore moiety--an aryl carboxylate amidated to the peptide chain--constitutes the formal amino terminus and is the starter residue of peptide assembly . Common to many arylpeptide systems is the activation by stand-alone adenylation domains and loading of the starter to discrete aryl carrier proteins (ArCPs) or ArCP domains which interact with the modules of the respective nonribosomal peptide synthetase (NRPS), assembling the next residues of the chain . Chain modification is another mechanism of nonribosomal chromopeptide synthesis where heteroaromatic rings such as thiazoles and oxazoles in peptides and polyketides are generated by heterocylizations of acyl- or peptidyl-cysteinyl or -serinyl/threonyl intermediates in each elongation step . In this review the basic mechanisms of chromophore acquisition in nonribosomal chromopeptide synthesis and mixed peptide/polyketide synthesis are illustrated by comparing the biosynthesis systems of various chromopeptides and chromopeptidic polyketide compounds. J Ind Microbiol Biotechnol, 2001 Aug, 27(2), 80 - 6 The influence of nitrate on microbial processes in oil industry production waters; Davidova I et al.; Sulfide accumulation due to bacterial sulfate reduction is responsible for a number of serious problems in the oil industry . Among the strategies to control the activity of sulfate-reducing bacteria (SRB) is the use of nitrate, which can exhibit a variety of effects . We investigated the relevance of this approach to souring oil fields in Oklahoma and Alberta in which water flooding is used to enhance oil recovery . SRB and nitrate-reducing bacteria (NRB) were enumerated in produced waters from both oil fields . In the Oklahoma field, the rates of sulfate reduction ranged from 0.05 to 0.16 microM S day(-1) at the wellheads, and an order of magnitude higher at the oil-water separator . Sulfide production was greatest in the water storage tanks in the Alberta field . Microbial counts alone did not accurately reflect the potential for microbial activities . The majority of the sulfide production appeared to occur after the oil was pumped aboveground, rather than in the reservoir . Laboratory experiments showed that adding 5 and 10 mM nitrate to produced waters from the Oklahoma and Alberta oil fields, respectively, decreased the sulfide content to negligible levels and increased the numbers of NRB . This work suggests that sulfate reduction control measures can be concentrated on aboveground facilities, which will decrease the amount of sulfide reinjected into reservoirs during the disposal of oil field production waters. Dynamis, 1998, 18, 427 - 46 {The impact of germ theory in the genesis of cancer . Consequences for surgical treatment in the victorian era}; Pereira Poza A; We use texts by preeminent figures in Victorian surgery at the end of the nineteenth century and information about their role in disseminating the germ theory to analyse the impact of this new etiologic element in the genesis of cancer . We trace the career of William Watson Cheyne (1852-1932), a disciple of Lister, and of many other surgeons of his generation, to outline the changes in the approach to treatment for cancer, the theoretical basis for these changes, and the role of a new conceptualization of cancer in the light of the microbial theory . This theory, among many other better-known factors, helped establish the foundation for radical surgery which became widespread in oncological treatment during the final decade of the nineteenth century. Genes Immun, 2001 Oct, 2(6), 323 - 8 Mannan-binding lectin (MBL) gene polymorphisms in ulcerative colitis and Crohn's disease; Rector A et al.; The inflammatory bowel diseases (IBD), Crohn's disease (CD), and ulcerative colitis (UC), are complex multifactorial traits involving both environmental and genetic factors . Mannan-binding lectin (MBL) plays an important role in non-specific immunity and complement activation . Point mutations in codons 52, 54 and 57 of exon 1 of the MBL gene are associated with decreased MBL plasma concentrations and increased susceptibility to various infectious diseases . If these MBL mutations could lead to susceptibility to putative IBD-etiological microbial agents, or could temper the complement-mediated mucosal damage in IBD, MBL could function as the link between certain microbial, immunological and genetic factors in IBD . In this study, we investigated the presence of the codon 52, 54 and 57 mutations of the MBL gene in 431 unrelated IBD patients, 112 affected and 141 unaffected first-degree relatives, and 308 healthy control individuals . In the group of sporadic IBD patients (n = 340), the frequency of the investigated MBL variants was significantly lower in UC patients when compared with CD patients (P = 0.01) and with controls (P = 0.02) . These results suggest that MBL mutations which decrease the formation of functional MBL could protect against the clinical development of sporadic UC, but not of CD . This could be explained by the differential T-helper response in both diseases. Proc Natl Acad Sci U S A, 1997 Aug 5, 94(16), 8284 - 91 Potential responses of soil organic carbon to global environmental change; Trumbore SE; Recent improvements in our understanding of the dynamics of soil carbon have shown that 20-40% of the approximately 1,500 Pg of C stored as organic matter in the upper meter of soils has turnover times of centuries or less . This fast-cycling organic matter is largely comprised of undecomposed plant material and hydrolyzable components associated with mineral surfaces . Turnover times of fast-cycling carbon vary with climate and vegetation, and range from <20 years at low latitudes to >60 years at high latitudes . The amount and turnover time of C in passive soil carbon pools (organic matter strongly stabilized on mineral surfaces with turnover times of millennia and longer) depend on factors like soil maturity and mineralogy, which, in turn, reflect long-term climate conditions . Transient sources or sinks in terrestrial carbon pools result from the time lag between photosynthetic uptake of CO2 by plants and the subsequent return of C to the atmosphere through plant, heterotrophic, and microbial respiration . Differential responses of primary production and respiration to climate change or ecosystem fertilization have the potential to cause significant interrannual to decadal imbalances in terrestrial C storage and release . Rates of carbon storage and release in recently disturbed ecosystems can be much larger than rates in more mature ecosystems . Changes in disturbance frequency and regime resulting from future climate change may be more important than equilibrium responses in determining the carbon balance of terrestrial ecosystems. Proc Natl Acad Sci U S A, 1995 May 9, 92(10), 4158 - 63 Function of the oxidative burst in hypersensitive disease resistance; Tenhaken R et al.; Microbial elicitors or attempted infection with an avirulent pathogen strain causes the rapid production of reactive oxygen intermediates . Recent findings indicate that H2O2 from this oxidative burst plays a central role in the orchestration of the hypersensitive response: (i) as the substrate driving the cross-linking of cell wall structural proteins to slow microbial ingress prior to the deployment of transcription-dependent defenses and to trap pathogens in cells destined to undergo hypersensitive cell death, (ii) as a local threshold trigger of this programmed death in challenged cells, and (iii) as a diffusible signal for the induction in adjacent cells of genes encoding cellular protectants such as glutathione S-transferase and glutathione peroxidase . These findings provide the basis for an integrated model for the orchestration of the localized hypersensitive resistance response to attack by an avirulent pathogen. Proc Natl Acad Sci U S A, 1992 Jul 1, 89(13), 5834 - 6 Inhibition of assimilatory nitrate reductase activity in soil by glutamine and ammonium analogs; McCarty GW et al.; Recent work in our laboratory indicated that the inhibitory effect of ammonium (NH4+) on assimilatory nitrate reductase (ANR) activity in soil is not due to NH4+ per se but to glutamine formed by microbial assimilation of NH4+ . To test this conclusion, we studied the effects of eight analogs of L-glutamine (L-glutamic acid gamma-methyl ester, L-glutamic acid gamma-hydrazide, L-glutamic acid gamma-hydroxamate, L-glutamic acid gamma-ethyl ester, L-glutamic acid dimethyl ester, L-asparagine, L-aspartic acid beta-methyl ester, and L-aspartic acid beta-hydroxamate) and two analogs of ammonium (hydroxylamine and methylamine) on ANR activity in soil slurries . The studies with the L-glutamine analogs showed that all except L-glutamic acid dimethyl ester inhibited ANR activity in soil . The sharp contrast observed between the strong inhibitory effect of L-glutamic acid gamma-methyl ester on ANR activity and the complete lack of an inhibitory effect with the corresponding dimethyl ester suggests that only the free-acid form of glutamine effectively inhibits ANR activity . The studies with hydroxylamine and methylamine showed that both of these ammonium analogs inhibited ANR activity in soil and that this inhibition was dependent upon glutamine synthetase activity . This dependence indicates that inhibition of ANR activity by hydroxylamine and methylamine was due to formation of the glutamine analogs L-glutamic acid gamma-hydroxamate and L-glutamic acid gamma-methylamide, respectively . These observations support the conclusion that the inhibitory effect of NH4+ on ANR activity in soil is due to glutamine formed by microbial assimilation of NH4+. Res Microbiol, 2001 Sep, 152(7), 671 - 8 Estimation of the abundance of the cadmium resistance gene cadA in microbial communities in polluted estuary water; Oger C et al.; We describe herein a molecular method for estimating the abundance of the cadA gene, which encodes a Cd2+/ATPase protein transporter, in bacterial DNA extracted from samples of environmental water . Competitive polymerase chain reaction (cPCR) may be the most appropriate technique for assessing the prevalence of the cadA gene in microbial communities in highly heterogeneous and polluted environments, such as the Seine estuary (France) . We describe the development of this method: (i) the choice of two specific primers, based on the sequences encoding the cadmium binding site and the ion channel domains; (ii) the construction of a competitor sequence and assessment of its amplification efficiency; and (iii) the estimation of the copy number of the cadA gene . The cadA content in the bacterial community is expressed as the number of gene copies per ng of total DNA extracted, which is independent of the DNA extraction yield . This molecular procedure was improved to analyze cadA levels in bacterial DNA extracted from estuary water accidentally contaminated with cadmium . Results revealed a subsequent increase in the copy number of the cadA gene in the microbial community. Prikl Biokhim Mikrobiol, 2001 Sep-Oct, 37(5), 593 - 600 {Immunosuppressors in pathogenesis of potato-pathogen blight}; Ozeretskovskaia OL et al.; The properties and effects of two plant resistance suppressors (1,3-beta-1,6-beta-glucan and a pentasaccharide of xyloglucan origin) involved in the pathosystem of potato (Solanum tuberosum) and the causal agent of blight (Phytophthora infestans (Mont) de Bary) were compared . The microbial 1,3-beta-1,6-beta-glucan suppressed the defense response over a narrow concentration range (10(-2) M), whereas the plant pentasaccharide had a broad range of effective concentrations (10(-12) to 10(-6) M) . In the pathosystem of potato-causal agent of late blight, the beta-glucan caused a local and race-specific suppressor effect on the plant host defense response . In contrast, the pentasaccharide caused both local and systemic suppression of potato resistance, and the presence of terminal fucosyl residue in the xyloglucan oligosaccharine played a decisive role in its effect . The recognition of both suppressors by potato cell membrane sites is discussed. J Biotechnol, 2001 Dec 14, 92(1), 21 - 6 Efficient and selective microbial esterification with dry mycelium of Rhizopus oryzae; Gandolfi R et al.; The use of dry mycelium of Rhizopus oryzae as biocatalyst for ester production in organic solvent has been studied . Mycelia with notable carboxylesterase activity were produced when different Tweens (20, 40, 60 and 80) were employed as main carbon source for the growth . Dry mycelium of four strains of Rhizopus oryzae proved effective for efficiently catalysing the synthesis of different flavour esters (hexylacetate and butyrate, geranylacetate and butyrate) starting from the corresponding alcohol and free acid, including acetic acid . The esterification of the racemic mixture of 2-octanol and butyric acid proceeded with high enantioselectivity (R-ester produced with enantiomeric excess > or =97%) when Rhizopus oryzae CBS 112.07 and Rhizopus oryzae CBS 260.28 were employed. Int J Food Microbiol, 2001 Sep 28, 69(3), 209 - 15 Considering uncertainty in comparing the burden of illness due to foodborne microbial pathogens; Powell M et al.; The uncertainty attendant to burden-of-illness estimates should be taken into account in comparing the public health impact of different foodborne pathogens . In this paper, decision analysis concepts are applied to the comparisons of pathogen-specific burden-of-illness estimates . In situations wherein the magnitude of uncertainty varies, the rank order of pathogen-specific burden-of-illness estimates is sensitive to the decisional criteria applied . To illustrate the magnitude of attendant uncertainty in pathogen-specific foodborne-illness estimates, probabilistic risk assessment methods are used to characterize the uncertainty regarding the burden of illness due to Escherichia coli O157:H7 . The magnitude of uncertainty about the burden of food-related illness due to E . coli O157:H7 is substantial, ranging from less than 50,000 to more than 120,000 cases/year . This example underscores the importance of considering the uncertainty attendant to burden-of-illness estimates in comparing the public health impacts of different pathogens . Although some would argue that the expected value of the number of illnesses provides the "best estimate" for decision-making, this merely reflects a decision-making rule of convention and not a scientific truism. Clin Invest Med, 2001 Oct, 24(5), 250 - 7 Inflammatory bowel disease: lessons from the IL-10 gene-deficient mouse; Madsen KL; The pathogenesis of Crohn's disease likely involves multifactorial interactions between genetic factors and environmental triggers . The most recent studies suggest that luminal bacteria are a significant factor in the onset and chronicity of inflammation . In interleukin-10 (IL-10) gene-deficient mice a Crohn's-like colitis develops when the mice are raised under conventional animal care facilities but fails to develop when they are raised under germ-free conditions . These mice demonstrate significant alterations in the species and the levels of bacteria colonizing the colon, suggesting that genetic factors in the host may be critical in controlling bacterial colonization . In addition, early treatment of IL-10 gene-deficient mice with antibiotics can prevent the development of colitis in later life, suggesting that early events during the neonatal period can influence later disease progression . Recent work has focused on using probiotic bacterial mixtures to alter the microbial balance in the colon in attempts to reduce inflammation . The use of the VSL-3 probiotic mixture in the IL-10 gene-deficient mouse resulted in a complete normalization of physiological transport function and barrier integrity, in conjunction with a reduction in mucosal secretion of TNF-alpha and IFN-gamma . Further, it would appear that a soluble factor is released from a bacterium found in the VSL-3 mixture that can act directly on the epithelium to enhance barrier integrity . Results from animal models of inflammatory bowel disease suggest that genetically susceptible hosts can mount a pathogenic cellular immune response to specific nonpathogenic bacterial species, as a consequence of defective immunologic tolerance and lack of appropriate mucosal defences . Probiotic bacteria appear to be a promising new alternative for the treatment of clinical conditions that are associated with alterations in gut barrier function, including Crohn' s disease. J Exp Med, 2001 Oct 15, 194(8), 1187 - 94 T cell-independent interleukin 15Ralpha signals are required for bystander proliferation; Lodolce JP et al.; Cytokine driven or "bystander" proliferation of T cells occurs in vivo independently of major histocompatibility complex-T cell receptor interactions . This process may be important for supporting T cell homeostasis and facilitating T cell responses to microbial antigens, and may involve the cytokine interleukin (IL)-15 . In this study, we find that IL-15Ralpha-deficient (IL-15Ralpha(-/-)) mice fail to undergo poly I:C or IL-15 driven bystander proliferation of CD8(+) T cells . Surprisingly, IL-15Ralpha(-/-) CD8(+) T cells proliferate in response to poly I:C when adoptively transferred into normal mice, and normal CD8(+) T cells fail to proliferate in IL-15Ralpha(-/-) mice . Normal mice reconstituted with IL-15Ralpha(-/-) bone marrow cells also fail to exhibit bystander responses . Thus, CD8(+) T cell independent IL-15Ralpha signals from radiation sensitive hematopoietic cells are likely required for bystander responses . Moreover, normal CD8(+) T cells proliferate in IL-15Ralpha(-/-) mice after treatment with IL-15 . Therefore, IL-15Ralpha signals may mediate a positive feedback loop involving the further physiological production of IL-15 . These findings provide new insights into how IL-15Ralpha supports memory phenotype CD8(+) T cell proliferation, and suggest novel mechanisms by which memory CD8(+) T cells are maintained in vivo. J Biol Chem, 2001 Dec 21, 276(51), 47950 - 7 Epub 2001 Oct 15. Lipopolysaccharide-induced expression of interferon-beta mediates the timing of inducible nitric-oxide synthase induction in RAW 264.7 macrophages; Jacobs AT et al.; The production of nitric oxide by macrophages has been implicated as a host defense mechanism against microbial pathogens and tumor cells . Recent reports have implicated interferon-alpha/beta (IFN-alpha/beta) as an autocrine/paracrine signal critical for the induction of murine iNOS . In this report we have systematically investigated the role of IFN-beta in the induction of iNOS in the murine macrophage cell line, RAW 264.7 . First, we demonstrate that IFN-beta expression is highly up-regulated, and is secreted in response to lipopolysaccharide (LPS) . Treatment of RAW macrophages with LPS results in a time-dependent phosphorylation of STAT-1 on both tyrosine residue 701 (Tyr-701) and serine residue 727 (Ser-727) that is consistent with the timing of endogenous IFN-beta expression . LPS also induces interferon regulatory factor-1 expression with similar kinetics . We further demonstrate that exogenous IFN-beta accelerates the induction of iNOS by LPS . The acceleration of iNOS induction is observed at the levels of transcription, protein expression, and NO formation . Accordingly, we propose that the cytokine environment of macrophages may determine the rate and magnitude of nitric oxide production, thereby regulating the cytotoxic response to pathogen challenge. Perspect Biol Med, 2001 Fall, 44(4), 594 - 607 More on Merde; Lewin RA; Whereas food has always received much attention in conversation, commerce, and the literature, the subject of feces has been comparatively neglected.To fill this lacuna, a small book on comparative coprology was recently published (Lewin 1999).The present article aims to supplement this book with a review of overlooked or new items relating to biological and medical aspects of coprology, notably chemical and microbial components of human and animal feces, their uses as fertilizers, and a few other sociological impacts. J Biol Chem, 2001 Dec 14, 276(50), 47070 - 7 Epub 2001 Oct 11. Crustacean immunity . Antifungal peptides are generated from the C terminus of shrimp hemocyanin in response to microbial challenge; Destoumieux-Garzon D et al.; We report here the isolation from plasma of two penaeid shrimp species of novel peptides/polypeptides with exclusive antifungal activities . A set of three molecules was purified with molecular masses at 2.7 kDa (Penaeus vannamei), 7.9 kDa, and 8.3 kDa (Penaeus stylirostris) . Primary structure determination was performed by a combination of Edman degradation and mass spectrometry . The peptides display 95-100% sequence identity with a C-terminal sequence of hemocyanin, indicating that they are cleaved fragments of the shrimp respiratory protein . Specific immunodetection of the hemocyanin-derived (poly)peptides revealed that experimental microbial infections increase their relative concentration in plasma as compared with nonstimulated animals . Thus, the production of antifungal (poly)peptides by limited proteolysis of hemocyanin could be relevant to a shrimp immune reaction that would confer a new function to the multifunctional respiratory pigment of crustaceans. Lancet, 2001 Oct 6, 358(9288), 1129 - 33 Exposure to farming in early life and development of asthma and allergy: a cross-sectional survey; Riedler J et al.; BACKGROUND: A farming environment protects against development of asthma, hay fever, and atopic sensitisation in children . We aimed to establish whether increased exposure to microbial compounds has to occur early in life to affect maturation of the immune system and thereby reduces risk for development of allergic diseases . METHODS: We did a cross-sectional survey in rural areas of Austria, Germany, and Switzerland . 2618 (75%) of 3504 parents of 6-13-year-old children completed a standardised questionnaire on asthma, hay fever, and atopic eczema . Children from farming families, and a random sample of non-farmers' children, who gave consent for blood samples to be obtained for measurements of specific serum IgE antibodies to common allergens were invited to participate (n=901) . FINDINGS: Exposure of children younger than 1 year, compared with those aged 1-5 years, to stables and consumption of farm milk was associated with lower frequencies of asthma (1% {3/218} vs 11% {15/138}), hay fever (3% {7} vs 13% {18}), and atopic sensitisation (12% {27} vs 29% {40}) . Protection against development of asthma was independent from effect on atopic sensitisation . Continual long-term exposure to stables until age 5 years was associated with the lowest frequencies of asthma (0.8% {1/122}), hay fever (0.8% {1}), and atopic sensitisation (8.2% {10}) . INTERPRETATION: Long-term and early-life exposure to stables and farm milk induces a strong protective effect against development of asthma, hay fever, and atopic sensitisation. Crit Rev Microbiol, 2001, 27(3), 223 - 37 Can synchronous cultures of bacteria be manufactured? Koch AL. The bacterial cell cycle is simpler and different than that of the typical eukaryotic cell cycle . The selective pressure during evolution has been directed to achieve optimal growth of the individual free-living microbial cell instead of a variety of replication rates of the differentiated cell within an entire multicellular organism . This means that for most bacterial cells division depends more critically on their success in acquiring and using resources than is the case for most eukaryotic cells . The further implication is that bacterial cells somehow measure their own success in growth and from this 'decide' when they should attempt cell cycle events such as cell division and chromosome replication . On the assumption that bacterial division is responsive, directly or indirectly, to cell size, the cell cycle is analyzed here through Monte Carlo simulations . The results are used to consider the possibility of generating bacterial cultures growing synchronous . Because the precision of the size-at-division is surprisingly good, it appears that some organisms, at least, have a sensory mechanism that responds to their success in cell growth . It is known that the division size of some strains, however, is more precisely regulated than in others . Also, some strains are more precise in dividing the mother's cell cytoplasm to give the same sized daughters . Because some strains are much more precise than others, the possibility is raised that useful synchrony could be obtained with selected strains that are precise in these two aspects . These cultures would useful in studying other aspect of the physiology of cell growth. Environ Toxicol Chem, 2001 Oct, 20(10), 2158 - 64 Trophic transfer and passive uptake of a polychlorinated biphenyl in experimental marine microbial communities; Wallberg P et al.; To study the uptake mechanisms of 2,2',4,4',6,6'-hexachlorobiphenyl (HxCB 153) in microplankton with different feeding strategies, two laboratory communities were used . Trophic transfer of HxCB 153 was tested in a heterotrophic microbial food web consisting of bacteria, flagellates, and ciliates . Passive uptake was tested in a community consisting of algae and bacteria . The experiments were conducted over 6 d, and samples were retrieved daily . In the heterotrophic food web, a significant increase of the HxCB 153 concentration was observed in the top predator level (ciliates, p < 0.05), where the concentration doubled during the 3 d of the experiment . A concomitant decrease was observed in the ciliate prey (flagellates), indicating that HxCB 153 was redistributed due to trophic transfer . On average, 33% of the HxCB 153 was sorbed to ciliates over the course of the experiment . In the experiment with algae and bacteria, the HxCB 153 concentrations were relatively stable over time . The largest fraction partitioned into bacteria (57%), whereas only 4% of the HxCB 153 sorbed to the algae . The uptake was 8-fold higher in ciliates than in algae, although the algal biomass was 10-fold higher . The results imply that trophic transfer may be a significant transport route of more hydrophobic organic contaminants (HOCs) in plankton communities . In transfer models, this pathway may be taken into consideration so that the transport rate of HOCs to higher trophic levels is not underestimated. Acta Ophthalmol Scand, 2001 Oct, 79(5), 479 - 83 Contact lens induced keratitis associated with contact lens wear; Dejaco-Ruhswurm I et al.; PURPOSE: To evaluate clinical characteristics, risk factors, management and outcome of contact lens induced keratitis (CLIK) associated with contact lens wear . METHODS: The study comprised all consecutive patients presenting with contact lens related presumed microbial keratitis during a 12-month period at our department . Detailed demographic data, type of contact lens, duration of lens wear, wearing schedule and lens hygiene were derived from a self-administered questionnaire . Severity of ulcer, corneal scrapings, treatment and final outcome were evaluated . RESULTS: 27 patients with CLIK, some of which may have been sterile peripheral infiltrates, due to contact lens wear were detected . In the majority of the cases patients had used disposable soft contact lenses (89%) and most of them had a daily wearing schedule (78%) . 51.8% patients cleaned their lenses regularly . 6 (22%) applied no disinfection since their lenses were disposable on removal . In 3 of our cases with CLIK, penetrating keratoplasty had to be performed . CONCLUSION: Disposable contact lenses seem to have been a predisposing factor for contact lens induced keratitis also when used on a daily wear schedule . Insufficient contact lens care products and/or manufacturing characteristics may be responsible for CLIK, which is also observed in otherwise compliant contact lens users . In 3 of our patients with CLIK keratoplasty became necessary, indicating that contact lens induced keratitis may result in severe corneal complications. Immunol Res, 2001, 24(2), 163 - 76 C-reactive protein, inflammation, and innate immunity; Mortensen RF; The circulating acute phase reactant C-reactive protein (CRP) has traditionally been characterized as an effector of nonclonal host resistance since it activates the classical complement cascade and mediates phagocytosis, but it is also capable of regulating inflammation . The three-dimensional structure of human CRP has revealed the molecular basis for complement activation and binding of phosphate monoesters . CRP gene expression by liver hepatocytes in response to cytokines (IL-1beta and IL-6) released in tissues requires several transcription factors which interact . Elevated levels of CRP are a prognostic marker for coronary artery disease; however, the role of CRP in atheriosclerosis remains unknown . CRP also mediates direct host protection to some microbial pathogens via its opsonic activity through certain Fcgamma-receptors . The CRP response may be one of the links between nonspecific innate immunity and specific clonal immunity. Prog Histochem Cytochem, 2001, 36(3), 185 - 259 Maintaining corneal integrity how the "window" stays clear; Kurpakus-Wheater M et al.; The anterior surface of the eye is composed of the cornea, conjunctiva, and the zone between the two called the limbus . The cornea must maintain optical clarity to retain good vision . However, the ocular surface is vulnerable to trauma, microbial infection, and exposure to environmental toxins . This places the cornea, especially, at risk for disruptions of the epithelial barrier and subsequent immunopathological events . Cell-cell and cell-matrix attachment junctions incorporating adhesion molecules ensure that the epithelial barrier remains intact . Protein components of the basement membrane, including laminins, are vital to the adhesion of corneal epithelial cells to the underlying stroma and function to enhance the strength of the bond between epithelium and connective tissue . Epithelial cells also play an early and crucial role in the initiation of ocular surface responses should a potentially antigenic molecule enter into deeper corneal tissues . For example, epithelial cells may produce and release cytokines such as interleukin-1 (IL-1) . The delicate balance between the matrix metalloproteinases (MMPs) and tissue inhibitors of metalloproteinases (TIMPs) are central to mechanisms regulating dissolution of the extracellular matrix that may be a consequence of infection or wound healing . Adhesion molecules, cytokines and chemokines, and MMPs and TIMPs thus participate in the corneal response to immunologic challenge or wounding . They may also be involved in corneal pathologies associated with genetic diseases, diabetes, and vitamin A deficiency . In addition these molecules are components of cellular pathways underlying the clinical complications often observed with contact lens wear and refractive surgeries used to improve visual acuity. Chemosphere, 2001 Oct, 45(3), 315 - 22 Chemical characteristics of organic aerosol in Bab-Ezzouar (Algiers) . Contribution of bituminous product manufacture; Yassaa N et al.; The organic compositions of atmospheric particulate matter from Bab-Ezzouar (Algiers) have been investigated to assess the air pollution levels suspected to be caused by asphalt product and yeast manufactures . After a medium-volume air sampling, soxhlet extraction, alumina elution and HPLC separation, the extracts were analysed by high-resolution gas chromatography (HRGC) and gas chromatography coupled to mass spectrometry (GC-MS) . The composition of n-alkane and polycyclic aromatic hydrocarbons (PAH) fractions reflected the petrogenic origin from the emission of asphalt materials production in addition to vascular plant wax emissions . In contrast, microbial activities seemed to play the main role for the presence of n-alkanoic acids at Bab-Ezzouar . The sole nitrated polycyclic aromatic hydrocarbons (NPAH) observed, i.e., 2-nitrofluoranthene (2NFA), was very likely to arise from gas-phase photochemical reaction of parent PAH in the atmosphere . The total aerial levels ranged from 75 to 206 ng m(-3) for n-alkanes, from 153 to 345 ng m(-3) for n-alkanoic acids and from 44 to 100 ng m(-3) for PAH and NPAH . Although the samples were collected during the hot season, the levels of these pollutants seemed to be important and of environmental concern, especially for PAH species. Am J Vet Res, 2001 Oct, 62(10), 1519 - 24 Involvement of microbial respiratory pathogens in acute interstitial pneumonia in feedlot cattle; Loneragan GH et al.; OBJECTIVE: To evaluate viral and bacterial respiratory pathogens and Mycoplasma spp isolated from lung tissues of cattle with acute interstitial pneumonia (AIP) and cattle that had died as a result of other causes . SAMPLE POPULATION: 186 samples of lung tissues collected from cattle housed in 14 feedlots in the western United States . PROCEDURE: Lung tissues were collected during routine postmortem examination and submitted for histologic, microbiologic, and toxicologic examinations . Histologic diagnoses were categorized for AIP, bronchopneumonia (BP), control samples (no evidence of disease), and other disorders . RESULTS: Cattle affected with AIP had been in feedlots for a mean of 1272 days before death, which was longer than cattle with BP and control cattle . Detection of a viral respiratory pathogen (eg, bovine respiratory syncytial virus {BRSV}, bovine viral diarrhea virus, bovine herpesvirus 1, or parainfluenza virus 3) was not associated with histologic category of lung tissues . Bovine respiratory syncytial virus was detected in 8.3% of AIP samples and 24.0% of control samples . Histologic category was associated with isolation of an aerobic bacterial agent and Mycoplasma spp . Cattle with BP were at greatest risk for isolation of an aerobic bacterial agent and Mycoplasma spp . CONCLUSIONS AND CLINICAL RELEVANCE: Analysis of these results suggests that AIP in feedlot cattle is not a consequence of infection with BRSV . The increased, risk of isolation of an aerobic bacterial agent from cattle with AIP, compared with control cattle, may indicate a causal role or an opportunistic infection that follows development of AIP. Eur J Immunol, 2001 Oct, 31(10), 3026 - 37 Toll-like receptor expression reveals CpG DNA as a unique microbial stimulus for plasmacytoid dendritic cells which synergizes with CD40 ligand to induce high amounts of IL-12; Krug A et al.; Human plasmacytoid dendritic cells (DC) (PDC, CD123+) and myeloid DC (MDC, CD11c+) may be able to discriminate between distinct classes of microbial molecules based on a different pattern of Toll-like receptor (TLR) expression . TLR1-TLR9 were examined in purified PDC and MDC . TLR9, which is critically involved in the recognition of CpG motifs in mice, was present in PDC but not in MDC . TLR4, which is required for the response to LPS, was selectively expressed on MDC . Consistent with TLR expression, PDC were susceptible to stimulation by CpG oligodeoxynucleotide (ODN) but not by LPS, while MDC responded to LPS but not to CpG ODN . In PDC, CpG ODN supported survival, activation (CD80, CD86, CD40, MHC class II), chemokine production (IL-8, IP-10) and maturation (CD83) . CD40 ligand (CD40L) and CpG ODN synergized to activate PDC and to stimulate the production of IFN-alpha and IL-12 including bioactive IL-12 p70 . Previous incubation of PDC with IL-3 decreased the amount of CpG-induced IFN-alpha and shifted the cytokine response in favor of IL-12 . CpG ODN-activated PDC showed an increased ability to stimulate proliferation of naive allogeneic CD4 T cells, butTh1 polarization of developing T cells required simultaneous activation of PDC by CD40 ligation and CpG ODN . CpG ODN-stimulated PDC expressed CCR7, which mediates homing to lymph nodes . In conclusion, our studies reveal that IL-12 p70 production by PDC is under strict control of two signals, an adequate exogenous microbial stimulus such as CpG ODN, and CD40L provided endogenously by activated T cells . Thus, CpG ODN acts as an enhancer of T cell help, while T cell-controlled restriction to foreign antigens is maintained. J Immunol, 2001 Oct 15, 167(8), 4147 - 53 Induction of IL-10 and inhibition of experimental arthritis are specific features of microbial heat shock proteins that are absent for other evolutionarily conserved immunodominant proteins; Prakken BJ et al.; Bacterial heat shock proteins (hsp) are evolutionary conserved immunodominant proteins that manifest amino acid homologies with hsp present in mammalian cells . Preimmunization with mycobacterial hsp65 has been found to protect against various forms of experimental arthritis . As these protective effects have previously been attributed to induction of self homologue cross-reactive T cell responses, the question was raised as to whether this protective effect could be extended to other highly conserved and immunodominant microbial Ags with mammalian homologues . Therefore, we immunized Lewis rats with conserved bacterial Ags (superoxide dismutase, aldolase, GAPDH, and hsp70) . Although all Ags appeared highly immunogenic, we only found a protective effect in experimental arthritis after immunization with bacterial hsp70 . The protective effect of hsp70 was accompanied with a switch in the subclasses of hsp70-specific Abs, suggesting the induction of Th2-like response . The most striking difference between immunization with hsp70 and all other immunodominant Ags was the expression of IL-10 found after immunization with hsp70 . Even more, while immunization with hsp70 led to Ag-induced production of IL-10 and IL-4, immunization with aldolase led to increased production of IFN-gamma and TNF-alpha . Thus, the protective effect of conserved immunodominant proteins in experimental arthritis seems to be a specific feature of hsp . Therefore, hsp may offer unique possibilities for immunological intervention in inflammatory diseases. J Environ Sci (China), 2001 Jul, 13(3), 311 - 7 Combined effects of two sulfonylurea herbicides on soil microbial biomass and N-mineralization; el-Ghamry AM et al.; The interaction effect of two sulfonylurea herbicides, bensulfuron-methyl (B) and metsulfuron-methyl(M), were tested on microbial biomass C, N, N-mineralization and C/N ratio in a loamy sand soil . The herbicides were applied at various levels of: control (B0M0), 0.01 and 0.01 (B1M1), 0.01 and 0.1 (B1M2), and 0.01 and 1.0 (B1M3) microgram/g soil . Determinations of soil microbial biomass-C, N and N-mineralization contents were carried out at 1, 3, 5, 7, 10, 15, 25 and 45 days after herbicides application . The results showed that the soil microbial biomass-C (Cmic) and microbial biomass-N (Nmic) decreased consistently with the increasing rates of herbicides . The results further indicated that B1M1 and B1M2 caused a significant reduction in Cmic and Nmic within first 10 and 7 days of incubation, respectively, as compared with the control . These reductions in Cmic and Nmic were also significant (P = 0.05) with B1M3 application especially within first 15 days of incubation . A significant reduction in N-mineralization (N-min) was observed with high doses (B1M2, B1M3) of herbicides within first 5 days of incubation, while low rate (B1M1) failed to produce any significant effect . An increase in the soil microbial biomass C:N ratio was also noted. Eur J Clin Invest, 2001 Sep, 31(9), 821 - 31 Fcgamma receptors in autoimmune diseases; Fossati G et al.; Fcgamma-receptors (Fcgamma-R) recognise the Fc portion of IgG and thus form a link between humoral and cellular immunity . These receptors are expressed by a variety of immune cells, and they function in the binding of immune complexes or IgG-opsonised particles, such as microbial pathogens . The are three major types of Fcgamma-R, namely Fcgamma-RI (CD64), Fcgamma-RII (CD32) and Fcgamma-RIII (CD16), and these differ in their ability to bind IgG and complexes . There are many isoforms of these receptors and a number of recently identified polymorphisms in their structure . This review describes the structure and function of these Fcgamma-Rs, and highlights how gene deficiencies and polymorphisms may contribute to the pathology of human diseases. J Contam Hydrol, 2001 Oct, 51(3-4), 179 - 95 In situ assessment of microbial sulfate reduction in a petroleum-contaminated aquifer using push-pull tests and stable sulfur isotope analyses; Schroth MH et al.; Anaerobic microbial activities such as sulfate reduction are important for the degradation of petroleum hydrocarbons (PHC) in contaminated aquifers . The objective of this study was to evaluate the feasibility of single-well push-pull tests in combination with stable sulfur isotope analyses for the in situ quantification of microbial sulfate reduction . A series of push-pull tests was performed in an existing monitoring well of a PHC-contaminated aquifer in Studen (Switzerland) . Sulfate transport behavior was evaluated in a first test . In three subsequent tests, we injected anoxic test solutions (up to 1000 l), which contained 0.5 mM bromide (Br-) as conservative tracer and 1 mM sulfate (SO4(2-)) as reactant . After an initial incubation period of 42.5 to 67.9 h, up to 1100 l of test solution/groundwater mixture was extracted in each test from the same location . During the extraction phases, we measured concentrations of relevant species including Br-, SO4(2-) and sulfide (S(-II)), as well as stable sulfur isotope ratios (delta 34S) of extracted, unconsumed SO4(2-) and extracted S(-II) . Results indicated sulfate reduction activity in the vicinity of the test well . Computed first-order rate coefficients for sulfate reduction ranged from 0.043 +/- 0.013 to 0.130 +/- 0.015 day-1 . Isotope enrichment factors (epsilon) computed from sulfur isotope fractionation of extracted, unconsumed SO4(2-) ranged from 20.2 +/- 5.5@1000 to 22.8 +/- 3.4@1000 . Together with observed fractionation in extracted S(-II), isotope enrichment factors provided strong evidence for microbially mediated sulfate reduction . Thus, push-pull tests combined with stable sulfur isotope analyses proved useful for the in situ quantification of microbial sulfate reduction in a PHC-contaminated aquifer. Biotechnol Prog, 2001 Sep-Oct, 17(5), 852 - 9 Impact of nitrate-mediated microbial control of souring in oil reservoirs on the extent of corrosion; Nemati M et al.; The effect of microbial control of souring on the extent of corrosion was studied in a model system consisting of pure cultures of the nitrate-reducing, sulfide-oxidizing bacterium (NR-SOB) Thiomicrospira sp . strain CVO and the sulfate-reducing bacterium (SRB) Desulfovibrio sp . strain Lac6, as well as in an SRB consortium enriched from produced water from a Canadian oil reservoir . The average corrosion rate induced by the SRB consortium (1.4 g x m(-2) x day(-1)) was faster than that observed in the presence of strain Lac6 (0.2 g x m(-2) x day(-1)) . Examination of the metallic coupons at the end of the tests indicated a uniform corrosion in both cases . Addition of CVO and 10 mM nitrate to a fully grown culture of Lac6 or the SRB consortium led to complete removal of sulfide from the system and a significant increase in the population of CVO, as determined by reverse sample genome probing . In the case of the SRB consortium addition of just nitrate (10 mM) had a similar effect . When grown in the absence of nitrate, the consortium was dominated by Desulfovibrio sp . strains Lac15 and Lac29, while growth in the presence of nitrate led to dominance of Desulfovibrio sp . strain Lac3 . The addition of CVO and nitrate to the Lac6 culture or nitrate to the SRB consortium accelerated the average corrosion rate to 1.5 and 2.9 g x m(-2) x day(-1), respectively . Localized corrosion and the occurrence of pitting were apparent in both cases . Although the sulfide concentration (0.5-7 mM) had little effect on corrosion rates, a clear increase of the corrosion rate with increasing nitrate concentration was observed in experiments conducted with consortia enriched from produced water. Gastroenterol Clin North Am, 2001 Sep, 30(3), 837 - 54 Biotherapeutic agents in the treatment of infectious diarrhea; Elmer GW et al.; Biotherapeutic agents offer unique advantages over traditional treatments for infectious diarrhea, and several have been shown to be effective (Table 4) . These therapeutic microbial agents are most effective in types of infectious diseases that are associated with a disruption of the normal intestinal microecology (e.g., AAD, C . difficile disease) . The impact of biotherapeutic agents on rotaviral diarrhea is of special clinical importance because this is the most common cause of pediatric diarrhea, and there is no defined treatment . Strong efforts need to be made to limit antibiotic exposure in children . Biotherapeutic agents offer a safe and effective nonantibiotic method of treating this important pathogen, especially after the withdrawal of a rotaviral vaccine from the market by the FDA . However, for many biotherapeutic agents, well-done, placebo-controlled trials still are lacking, and not all types of infectious diarrhea respond to these agents . Continued research in this innovative therapeutic area is warranted. J Allergy Clin Immunol, 2001 Oct, 108(4 Suppl), S104 - 6 Activation of toll-like receptors by microbial lipoproteins: role in host defense; Modlin RL; Conserved throughout evolution, mammalian toll-like receptors (TLRs) participate in innate immune response to microbial pathogens . The TLRs mediate activation by microbial ligands, resulting in cytokine activation as well as other host defense mechanisms . Activation of TLRs also can result in tissue injury including manifestations of septic shock and host cell apoptosis . In this manner, the activation of mammalian TLRs in the context of infectious disease can contribute to host defense and immunopathology. Nat Cell Biol, 2001 Oct, 3(10), 891 - 6 Endoplasmic reticulum chaperone gp96 is required for innate immunity but not cell viability; Randow F et al.; Chaperone proteins are thought to promote the correct folding and assembly of newly synthesized proteins and to facilitate restoration of the folded state under environmental conditions that favour protein denaturation . They are among the most ubiquitous and highly conserved of all proteins . The eukaryotic endoplasmic reticulum (ER) chaperone gp96 in particular has long been thought to be indispensable for cell survival . Here we report that a screen for genes required for the immune response to bacterial endotoxins has identified a B-cell line deficient in gp96 . Absence of gp96 is compatible with cellular survival even under stress conditions and causes a defect in the formation of only a small subset of cell surface receptors . Toll-like receptors are retained intracellularly in the absence of gp96, explaining the unresponsiveness of the mutant to microbial stimuli. Am J Pathol, 2001 Oct, 159(4), 1199 - 209 Molecular signatures of sepsis: multiorgan gene expression profiles of systemic inflammation; Chinnaiyan AM et al.; During sepsis the host's system-wide response to microbial invasion seems dysregulated . Here we explore the diverse multiorgan transcriptional programs activated during systemic inflammation in a cecal ligation/puncture model of sepsis in rats . Using DNA microarrays representing 7398 genes, we examined the temporal sequence of sepsis-induced gene expression patterns in major organ systems including lung, liver, kidney, thymus, spleen, and brain . Although genes known to be associated with systemic inflammation were identified by our global transcript analysis, many genes and expressed sequence tags not previously linked to the septic response were also elucidated . Taken together, our results suggest activation of a highly complex transcriptional response in individual organs of the septic animal . Several overlying themes emerged from our genome-scale analysis that includes 1) the sepsis response elicited gene expression profiles that were either organ-specific, common to more than one organ, or distinctly opposite in some organs; 2) the brain is protected from sepsis-induced gene activation relative to other organs; 3) the thymus and spleen have an interesting cohort of genes with opposing gene expression patterns; 4) genes with proinflammatory effects were often balanced by genes with anti-inflammatory effects (eg, interleukin-1beta/decoy receptor, xanthine oxidase/superoxide dismutase, Ca2+-dependent PLA2/Ca2+-independent PLA2); and 5) differential gene expression was observed in proteins responsible for preventing tissue injury and promoting homeostasis including anti-proteases (TIMP-1, Cpi-26), oxidant neutralizing enzymes (metallothionein), cytokine decoy receptors (interleukin-1RII), and tissue/vascular permeability factors (aquaporin 5, vascular endothelial growth factor) . This global perspective of the sepsis response should provide a molecular framework for future research into the pathophysiology of systemic inflammation . Understanding, on a genome scale, how an organism responds to infection, may facilitate the development of enhanced detection and treatment modalities for sepsis. Biochemistry, 2001 Aug 14, 40(32), 9460 - 8 Protein interactions leading to conformational changes monitored by limited proteolysis: apo form and fragments of horse cytochrome c; Spolaore B et al.; Proteolysis experiments have been used to monitor the conformational transitions from an unfolded to a folded state occurring when the apo form of horse cytochrome c (cyt c) binds the heme moiety or when two fragments of cyt c form a native-like 1:1 complex . Proteinase K was used as a proteolytic probe, in view of the fact that the broad substrate specificity of this protease allows digestion at many sites along a polypeptide chain . The rather unfolded apo form of cyt c binds heme with a concomitant conformational transition to a folded species characterized by an enhanced content of helical secondary structure . While the holoprotein is fully resistant to proteolytic digestion and the apoprotein is digested to small peptides, the noncovalent complex of the apoprotein and heme exhibits an intermediate resistance to proteolysis, in agreement with the fact that the more folded structure of the complex makes the protein substrate more resistant to proteolysis . The noncovalent native-like complex of the two fragments 1-56 and 57-104 of cyt c, covering the entire polypeptide chain of 104 residues of the protein, is rather resistant to proteolysis, while the individual fragments are easily digested . Fragment 57-104 is fast degraded to several peptides, while fragment 1-56 is slowly degraded stepwise from its C-terminal end, leading initially mostly to fragments 1-48 and 1-40 and, at later stages of proteolysis, fragments 1-38, 1-35, 1-33, and 1-31 . Thus, proteolysis data indicate that the heme containing fragment 1-56 has a rather compact core and a C-terminal flexible tail . Upon prolonged incubation of the complex of fragments 1-56 and 57-104 (nicked cyt c) with proteinase K, a chain segment is removed from the nicked protein, lea