Exp Gerontol, 2000 Aug, 35(5), 521 - 32 Role of redox-regulated transcription factors in inflammation, aging and age-related diseases; Lavrovsky Y et al.; A progressive rise of oxidative stress due to the altered redox homeostasis appears to be one of the hallmarks of the aging process . Reactive oxygen species (ROS) also serve as signaling agents for inflammation, a systemic defensive reaction against microbial pathogens and other foreign bodies . Changes in the pattern of gene expression through ROS-sensitive transcription factors give rise to both aging and inflammation phenotypes . Chronic oxidative stress and inflammatory reaction also lead to many age-associated diseases such as atherosclerosis and arthritis . Transcription factors that are directly influenced by ROS and proinflammatory cytokines include nuclear factor kappa B (NF-kappaB), activator protein 1 (AP-1), specificity protein 1 (Sp1), peroxisome proliferator-activated receptors (PPARs) and other members of the nuclear receptor superfamily . Here we describe the basic components of the intracellular redox control machinery and their dysregulation with age leading to altered transcription factor function and age-associated pathophysiology. Phys Rev Lett, 2000 Sep 18, 85(12), 2641 - 4 Predictions of gene family distributions in microbial genomes: evolution by gene duplication and modification; Yanai I et al.; A universal property of microbial genomes is the considerable fraction of genes that are homologous to other genes within the same genome . The process by which these homologues are generated is not well understood, but sequence analysis of 20 microbial genomes unveils a recurrent distribution of gene family sizes . We show that a simple evolutionary model based on random gene duplication and point mutations fully accounts for these distributions and permits predictions for the number of gene families in genomes not yet complete . Our findings are consistent with the notion that a genome evolves from a set of precursor genes to a mature size by gene duplications and increasing modifications. Microb Ecol, 2000 Jul, 40(1), 43 - 56 Variation of Microbial Rhizosphere Communities in Response to Crop Species, Soil Origin, and Inoculation with Sinorhizobium meliloti L33; Miethling R et al.; A greenhouse study with soil-plant microcosms was conducted in order to compare the effect of crop species, soil origin, and a bacterial inoculant on the establishment of microbial communities colonizing plant roots . Two crop species, alfalfa (Medicago sativa) and rye (Secale cereale), were grown separately in two soils collected from agricultural fields at different locations and with differing histories of leguminous crop rotation . A subset of microcosms was inoculated at 10(6) cfu g(-1) soil with the luciferase marker gene-tagged Sinorhizobium meliloti strain L33, a symbiotic partner of M . sativa . Microbial consortia were collected from the rhizospheres of alfalfa after 10 weeks of incubation and from rye after 11 weeks . S . meliloti L33 populations were one to two orders of magnitude higher in the rhizospheres of alfalfa than of rye . In soil with previous alfalfa cultivation, 80% of the alfalfa nodules were colonized by indigenous bacteria, while in the other soil alfalfa was colonized almost exclusively (>90%) with S . meliloti L33 . Three community-level targeting approaches were used to characterize the variation of the extracted microbial rhizosphere consortia: (1) Community level physiological profiles (CLPP), (2) fatty acid methyl ester analysis (FAME), and (3) diversity of PCR amplified 16S rRNA target sequences from directly extracted ribosomes, determined by temperature gradient gel electrophoresis (TGGE) . All approaches identified the crop species as the major determinant of microbial community characteristics . Consistently, the influence of soil was of minor importance, while a modification of the alfalfa-associated microbial community structure after inoculation with S . meliloti L33 was only consistently observed by using TGGE. Support Care Cancer, 2000 Sep, 8(5), 353 - 65 Oral complications of pediatric hematopoietic cell transplantation: diagnosis and management; Majorana A et al.; Oral complications are a significant cause of morbidity and potential mortality for children undergoing hematopoietic cell transplant (HCT) . Oral complications can occur at all stages of HCT and can interfere significantly with transplant recovery . Mucosal disease caused by conditioning regimen toxicity and infection are frequent clinical problems . Untreated dental caries and periodontal disease may result in severe infections of the mouth and/or life-threatening systemic spread of the microbial pathogens . In the course of chronic graft-versus-host disease (GVHD), which can complicate HCT, lichenoid and ulcerative lesions of the mucosa are observed . Furthermore, total-body irradiation utilized in the conditioning regimens can cause early xerostomia and consequent dental decay and also result in significant dental and skeletal developmental anomalies . The dental health care team should have a key role in the support of HCT patients . The team's primary responsibilities are those related to the prevention of severe infections originating in the mouth, which includes providing instruction on oral prophylaxis and hygiene as well as direct intervention . Prevention and/or diagnosis and management of oral complications of HCT by the dental team can improve the success of a transplant by reducing morbidity, improving the quality of life, and reducing the cost of care . The authors present specific protocols for the diagnosis and prevention and for the management of oral complications in pediatric HCT. Cell, 2000 Aug 4, 102(3), 325 - 34 Developmental control of endocytosis in dendritic cells by Cdc42; Garrett WS et al.; Dendritic cells (DCs) developmentally regulate antigen uptake by controlling their endocytic capacity . Immature DCs actively internalize antigen . However, mature DCs are poorly endocytic, functioning instead to present antigens to T cells . We have found that endocytic downregulation reflects a decrease in endocytic activity controlled by Rho family GTPases, especially Cdc42 . Blocking Cdc42 function by Toxin B treatment or injection of dominant-negative inhibitors of Cdc42 abrogates endocytosis in immature DCs . In mature DCs, injection of constitutively active Cdc42 or microbial delivery of a Cdc42 nucleotide exchange factor reactivates endocytosis . DCs regulate endogenous levels of Cdc42-GTP with activated Cdc42 detectable only in immature cells . We conclude that DCs developmentally regulate endocytosis at least in part by controlling levels of activated Cdc42. Clin Diagn Lab Immunol, 2000 Sep, 7(5), 759 - 63 Shipment impairs lymphocyte proliferative responses to microbial antigens; Betensky RA et al.; Lymphocyte proliferation assays (LPAs) are widely used to assess T-lymphocyte function of patients with human immunodeficiency virus infection and other primary and secondary immunodeficiency disorders . Since these assays require expertise not readily available at all clinical sites, specimens may be shipped to central labs for testing . We conducted a large multicenter study to evaluate the effects of shipping on assay performance and found significant loss of LPA activity . This may lead to erroneous results for individual subjects and introduce bias into multicenter trials. Plant J, 2000 Aug, 23(4), 431 - 40 Soluble phospholipase A2 activity is induced before oxylipin accumulation in tobacco mosaic virus-infected tobacco leaves and is contributed by patatin-like enzymes; Dhondt S et al.; Recent evidence suggests that oxidized lipid-derived molecules play significant roles in inducible plant defence responses against microbial pathogens, either by directly deterring parasite multiplication, or as signals involved in the induction of sets of defence genes . The synthesis of these oxylipins was hypothesized to be initiated by the phospholipase A2-mediated release of unsaturated fatty acids from membrane lipids . Here, we demonstrate that, in tobacco leaves reacting hypersensitively to tobacco mosaic virus, a strong increase in soluble phospholipase A2 (PLA2) activity occurs at the onset of necrotic lesion appearance . This rapid PLA2 activation occurred before the accumulation of 12-oxophytodienoic and jasmonic acids, two fatty acid-derived defence signals . Three PLA2 isoforms were separated and the most active enzyme was partially purified, its N-terminal sequence displaying similarity with patatin, the major storage protein in potato tubers . Three related tobacco patatin-like cDNAs, called NtPat1, NtPat2 and NtPat3, were cloned, with NtPat2 encoding the PLA2 isolated from infected leaves . RT-PCR experiments showed a rapid transcriptional activation of the three NtPat genes in virus-infected leaves, preceding the increase in PLA2 activity . Recombinant NtPat1 and NtPat3 enzymes were active in an assay using labelled bacterial membranes, and also displayed high bona fide PLA2 activity on phosphatidylcholine substrate . These results point to a possible new role of patatin-like phospholipases in inducible plant defence responses . The induction kinetics together with the enzymatic activity data indicate that the NtPat proteins may provide precursors for oxylipin synthesis during the hypersensitive response to pathogens. Mol Microbiol, 2000 Aug, 37(4), 703 - 16 The role of lateral gene transfer in the evolution of isoprenoid biosynthesis pathways; Boucher Y et al.; Lateral gene transfer (LGT) is a major force in microbial genome evolution . Here, we present an overview of lateral transfers affecting genes involved in isopentenyl diphosphate (IPP) synthesis . Two alternative metabolic pathways can synthesize this universal precursor of isoprenoids, the 1-deoxy-D-xylulose 5-phosphate (DOXP) pathway and the mevalonate (MVA) pathway . We have surveyed recent genomic data and the biochemical literature to determine the distribution of the genes composing these pathways within the bacterial domain . The scattered distribution observed is incompatible with a simple scheme of vertical transmission . LGT (among and between bacteria, archaea and eukaryotes) more parsimoniously explains many features of this pattern . This alternative scenario is supported by phylogenetic analyses, which unambiguously confirm several cases of lateral transfer . Available biochemical data allow the formulation of hypotheses about selective pressures favouring transfer . The phylogenetic diversity of the organisms involved and the range of possible causes and effects of these transfer events make the IPP biosynthetic pathways an ideal system for studying the evolutionary role of LGT. Lett Appl Microbiol, 2000 Aug, 31(2), 178 - 83 Monitoring the microbial contamination of beef carcass tissue with a rapid chromogenic Limulus amoebocyte lysate endpoint assay; Siragusa GR et al.; A chromogenic Limulus amoebocyte lysate (LAL) endpoint assay was found to be an accurate and rapid means of gauging levels of beef carcass microbial contamination within 10 min . The assay demonstrated a high correlation with the total mesophilic bacterial and coliform surface populations from inoculated beef carcass surface tissues . This assay was tested on a set of actual beef carcass surface samples (n = 121) demonstrating the utility of the chromogenic LAL test as a means of monitoring carcass microbial contamination in a near real-time fashion . Classifying the chromogenic LAL results into four contamination groups was found to be a sound means of utilizing the resultant chromogenic LAL data for detecting carcasses with high levels of microbial contamination . For beef carcass testing, this assay can be used with no instrumentation other than the required 37 degrees C incubator and, as an option, a microplate reader. Lett Appl Microbiol, 2000 Aug, 31(2), 118 - 22 Spatial distribution of 16S rRNA levels from uncultured acidobacteria in soil; Felske A et al.; The activity of uncultured acidobacteria was monitored in Dutch grassland soils by quantifying their ribosomes . These bacteria were detectable by five different 16S rRNA RT-PCR products in temperature gradient gel electrophoresis fingerprints . The ribosomes in surface soil samples were quantified with multiple competitive RT-PCR along a 1.5-km transect through the grassland . In total, the five members of the acidobacteria were estimated to contribute 4 x 1010 to 1 x 1011 ribosomes g soil-1, representing 7-14% of all bacterial ribosomes . These results indicate that ribosomes from acidobacteria are continuously present and abundant in soil and might contribute significantly to microbial activity in soil. Glycoconj J, 1999 Oct, 16(10), 607 - 15 A solid-phase glycosyltransferase assay for high-throughput screening in drug discovery research; Donovan RS et al.; Glycosyltransferases mediate changes in glycosylation patterns which, in turn, may affect the function of glycoproteins and/or glycolipids and, further downstream, processes of development, differentiation, transformation and cell-cell recognition . Such enzymes, therefore, represent valid targets for drug discovery . We have developed a solid-phase glycosyltransferase assay for use in a robotic high-throughput format . Carbohydrate acceptors coupled covalently to polyacrylamide are coated onto 96-well plastic plates . The glycosyltransferase reaction is performed with recombinant enzymes and radiolabeled sugar-nucleotide donor at 37 degrees C, followed by washing, addition of scintillation counting fluid, and measurement of radioactivity using a 96-well beta-counter . Glycopolymer construction and coating of the plastic plates, enzyme and substrate concentrations, and linearity with time were optimized using recombinant Core 2 beta1-6-N-acetylglucosaminyltransferase (Core 2 GlcNAc-T) . This enzyme catalyzes a rate-limiting reaction for expression of polylactosamine and the selectin ligand sialyl-Lewis(x) in O-glycans . A glycopolymer acceptor for beta1-6-N-acetylglucosaminyltransferase V was also designed and shown to be effective in the solid-phase assay . In a high-throughput screen of a microbial extract library, the coefficient of variance for positive controls was 9.4%, and high concordance for hit validation was observed between the Core 2 GlcNAc-T solid-phase assay and a standard solution-phase assay . The solid-phase assay format, which can be adapted for a variety of glycosyltransferase enzymes, allowed a 5-6 fold increase in throughput compared to the corresponding solution-phase assay. J Appl Microbiol, 2000 Aug, 89(2), 302 - 8 Influence of TNT transformation on microbial community structure in four different lake microcosms; Wikstrom P et al.; After World War II, large amounts of obsolete ammunition were dumped in various lakes in Sweden . Trinitrotoluene, TNT, was one of the main components of the dumped explosives . In this study, four different lake microcosms originating from lakes where relatively large amounts of ammunition were dumped were used to mimic the effect of TNT release on the natural microbial community . Increased microbial growth was found in lake microcosms amended with TNT . However, negligible mineralization of TNT was detected, suggesting that TNT was not utilized as a carbon source, but as a nitrogen source . Random amplified polymorphic DNA (RAPD) analysis indicated that the TNT induced no significant differences in microbial community composition and therefore, no major changes in natural selection, despite the increased microbial growth in the presence of the compound . More than 95% of the added TNT bound irreversibly to the sediments, possibly as a result of microbial transformation to reactive metabolites that subsequently bound covalently to components of the sediment . The results, taken together, suggest that no permanent change in the microbial ecology occurred as a result of the TNT amendment . This was probably due partly to the transient exposure of the microbial communities to the TNT before it became irreversibly bound to the sediment, and partly to the fact that TNT was not a primary growth substrate that strongly affects natural selection. Clin Exp Immunol, 2000 Sep, 121(3), 499 - 505 Enhancement of natural killer (NK) cell cytotoxicity and induction of NK cell-derived interferon-gamma (IFN-gamma) display different kinetics during experimental infection with Trypanosoma cruzi; Une C et al.; Early immunological activation involves an initial phase of cytokine activity and involvement of cell types such as NK cells . Such early immune responses are often decisive in resolution of microbial infection . NK cells reduce parasitaemia and enhance survival in experimental Trypanosoma cruzi infection, although the nature of these protective effects is not well understood . In this study, a detailed analysis of innate cytokine induction in the absence and presence of NK cells during the first 8 days of infection was performed . Following intraperitoneal infection with a high dose of parasites, reverse transcriptase-polymerase chain reaction showed that splenic mRNA for IFN-gamma appeared as a peak 24 h after infection and then reappeared 2-3 days later . In NK-depleted animals the first peak of IFN-gamma was absent and the second wave was slightly delayed . mRNA for IL-12 and tumour necrosis factor-alpha (TNF-alpha) as well as IFN-alpha protein in serum was only recorded 24 h after infection, at the same time as the IFN-gamma peak . NK depletion resulted in a small decrease of IL-12 mRNA levels, whereas TNF-alpha and IFN-alpha were not affected . NK cytotoxicity remained elevated throughout the 8 days and thus did not parallel the expression of IFN-gamma production by NK cells . We conclude that NK cell cytokine production and cytolytic activity play different roles in response to challenge with T . cruzi. J Clin Microbiol, 2000 Sep, 38(9), 3515 - 7 Identification of Mycobacterium neoaurum isolated from a neutropenic patient with catheter-related bacteremia by 16S rRNA sequencing; Woo PC et al.; A rapidly growing pigmented mycobacterial strain with an ambiguous biochemical profile was isolated from the blood culture taken through the Hickman catheter of a 9-year-old girl with acute lymphoblastic leukemia . Whole-cell fatty acid analysis showed that the best match profile was that of Mycobacterium aurum, but the similarity index was only 0.217, meaning that there were no good matches between the isolate and the organisms in the database of the Microbial Identification System . The 16S rRNA gene of the mycobacterial strain was amplified, agarose gel purified, and sequenced . There were 44 base differences between the gene sequence of the isolate and that of M . aurum but only one base difference between the sequence of the isolate and that of Mycobacterium neoaurum, showing that the isolate was indeed a strain of M . neoaurum by using this "gold standard." This represents the first case of M . neoaurum infection documented by 16S rRNA sequencing. Bioorg Med Chem Lett, 2000 Aug 21, 10(16), 1811 - 4 Inhibitors of bacterial tyrosyl tRNA synthetase: synthesis of four stereoisomeric analogues of the natural product SB-219383; Berge JM et al.; Synthetic analogues of the microbial metabolite SB-219383 have been synthesised with defined stereochemistry . Densely functionalised hydroxylamine containing amino acids were prepared by the addition of a glycine anion equivalent to sugar-derived cyclic nitrones . One of four stereoisomeric dipeptides incorporating these novel amino acids was found to be a potent and selective inhibitor of bacterial tyrosyl tRNA synthetase, suggesting analogous stereochemistry of the natural product. Appl Microbiol Biotechnol, 2000 Aug, 54(2), 168 - 72 The use of silica gel prepared by sol-gel method and polyurethane foam as microbial carriers in the continuous degradation of phenol; Branyik T et al.; A mixed microbial culture was immobilized by entrapment into silica gel (SG) and entrapment/ adsorption on polyurethane foam (PU) and ceramic foam . The phenol degradation performance of the SG biocatalyst was studied in a packed-bed reactor (PBR), packed-bed reactor with ceramic foam (PBRC) and fluidized-bed reactor (FBR) . In continuous experiments the maximum degradation rate of phenol (q(s)max) decreased in the order: PBRC (598 mg l(-1) h(-1)) > PBR (PU, 471 mg l(-1)h(-1)) > PBR(SG, 394 mg l(-1) h(-1)) > FBR (PU, 161 mg l(-1) h(-1)) > FBR (SG, 91 mg l(-1) h(-1)) . The long-term use of the SG biocatalyst in continuous phenol degradation resulted in the formation of a 100-200 microm thick layer with a high cell density on the surface of the gel particles . The abrasion of the surface layer in the FBR contributed to the poor degradation performance of this reactor configuration . Coating the ceramic foam with a layer of cells immobilized in colloidal SiO2 enhanced the phenol degradation efficiency during the first 3 days of the PBRC operation, in comparison with untreated ceramic packing. Infect Dis Obstet Gynecol, 2000, 8(3-4), 158 - 65 Effect of intravaginal clindamycin cream on pregnancy outcome and on abnormal vaginal microbial flora of pregnant women; Rosenstein IJ et al.; OBJECTIVES: To determine whether intravaginal clindamycin cream reduces the incidence of abnormal pregnancy outcome in women with abnormal vaginal microbial flora graded as intermediate or BV and to investigate the effect of the antibiotic on vaginal microbial flora . METHODS: A prospective cohort study of pregnant women in an antenatal clinic of a district general hospital . The subjects were 268 women who had abnormal vaginal microbial flora at first clinic visit by examination of a Gram-stained vaginal smear and 34 women with a normal vaginal flora . Two hundred and thirty-seven women were evaluable . Women with abnormal Gram-stained smears (graded as II or III) on clinic recall were randomised to receive treatment (intravaginal clindamycin cream) or placebo and followed to assess outcome of pregnancy, vaginal flora, and detection of Mycoplasma hominis and Ureaplasma urealyticum after treatment . RESULTS: Abnormal outcomes of pregnancy were not significantly different in treated and placebo groups by Chi square (P = 0.2) . However, women with grade III flora responded better to clindamycin than women with grade II flora by numbers of abnormal outcomes (P = 0.03) and return to normal vaginal flora (P = 0.01) (logistic regression analysis model) . This may be due to differences in vaginal bacterial species in these grades . Women whose abnormal vaginal flora had spontaneously returned to normal on follow-up and were therefore not treated (revertants) had as many abnormal outcomes as placebos suggesting that damage by abnormal bacterial species occurred early in pregnancy . CONCLUSIONS: Gram-stain screening distinguishing grade II from grade III flora may be helpful in prescribing treatment other than clindamycin for women with grade II flora . Earlier diagnosis and treatment may be more effective in preventing an abnormal outcome, possibly as soon as pregnancy is diagnosed or even offered as a pre-conception screen. Med J Malaysia, 1996 Mar, 51(1), 4 - 11 Microbial diseases in Malaysia: recent experiences; Arokiasamy JT; Microbial diseases continue to occur in Malaysia despite the marked socio-economic development that has been taking place in the country along with improvements in the medical, health, and environmental sectors . This paper highlights the continuing presence of the numerous microbial diseases including the emergence of new problems such as AIDS . Local publications dealing with work on several microbial diseases is reviewed to show that this group of diseases will pose challenges for a long while . Undoubtedly several other diseases that were relatively unrecognised in the past are increasingly being identified owing to recent availability of diagnostic facilities and equipments . The need for continued vigilance is emphasised. Adv Drug Deliv Rev, 2000 Sep 30, 43(2-3), 207 - 23 Lectin-mediated mucosal delivery of drugs and microparticles; Clark MA et al.; Absorption of drugs and vaccines at mucosal surfaces may be enhanced by conjugation to appropriate bioadhesins which bind to mucosal epithelia . Bioadhesins might also permit cell- and site-selective targeting . One approach is to exploit surface carbohydrates on mucosal epithelial cells for lectin-mediated delivery . We review work supporting the use of lectins as mucosal bioadhesins in the gastrointestinal and respiratory tracts, the oral cavity and the eye . The gastrointestinal tract is particularly favoured for mucosal delivery . Many studies have demonstrated that the antigen sampling intestinal M cells offer a portal for absorption of colloidal delivery vehicles . Evidence is presented that M cell targeting may be achieved using M cell-specific lectins, microbial adhesins or immunoglobulins . While many hurdles must be overcome before mucosal bioadhesins can guarantee consistent, safe, effective mucosal delivery, this is an exciting area of research that has important implications for future drug and vaccine formulation. FEMS Microbiol Ecol, 2000 Aug 1, 33(2), 129 - 137 Comparison of methods to investigate microbial populations in soils under different agricultural management; Lawlora K et al.; The microbial community in sludge-treated and nearby untreated soils was investigated using direct microscopic counting, plate culture, carbon substrate utilisation (Biolog), and fatty acid methyl esters . Long-term sewage sludge applications had resulted in higher concentrations of organic carbon and had altered other factors in the soil, including the concentration of metals . Bioluminescence was inhibited in assays of the sludge-treated soil, although microbial counts were similar in all soils . A detailed analysis of carbon substrate utilisation patterns and fatty acid methyl esters showed qualitative differences in the microbial populations . This work shows that a variety of approaches are required to assess microbial communities in soil where, despite large differences in land management, the populations are similar in size and overall composition. Appl Environ Microbiol, 2000 Sep, 66(9), 4068 - 73 Intracellular accumulation of polyphosphate by the yeast Candida humicola G-1 in response to acid pH; McGrath JW et al.; Cells of a newly isolated environmental strain of Candida humicola accumulated 10-fold more polyphosphate (polyP), during active growth, when grown in complete glucose-mineral salts medium at pH 5.5 than when grown at pH 7.5 . Neither phosphate starvation, nutrient limitation, nor anaerobiosis was required to induce polyP formation . An increase in intracellular polyP was accompanied by a 4.5-fold increase in phosphate uptake from the medium and sixfold-higher levels of cellular polyphosphate kinase activity . This novel accumulation of polyP by C . humicola G-1 in response to acid pH provides further evidence as to the importance of polyP in the physiological adaptation of microbial cells during growth and development and in their response to environmental stresses. Appl Environ Microbiol, 2000 Sep, 66(9), 3807 - 13 Relative contributions of bacteria, protozoa, and fungi to in vitro degradation of orchard grass cell walls and their interactions; Lee SS et al.; To assess the relative contributions of microbial groups (bacteria, protozoa, and fungi) in rumen fluids to the overall process of plant cell wall digestion in the rumen, representatives of these groups were selected by physical and chemical treatments of whole rumen fluid and used to construct an artificial rumen ecosystem . Physical treatments involved homogenization, centrifugation, filtration, and heat sterilization . Chemical treatments involved the addition of antibiotics and various chemicals to rumen fluid . To evaluate the potential activity and relative contribution to degradation of cell walls by specific microbial groups, the following fractions were prepared: a positive system (whole ruminal fluid), a bacterial (B) system, a protozoal (P) system, a fungal (F) system, and a negative system (cell-free rumen fluid) . To assess the interactions between specific microbial fractions, mixed cultures (B+P, B+F, and P+F systems) were also assigned . Patterns of degradation due to the various treatments resulted in three distinct groups of data based on the degradation rate of cell wall material and on cell wall-degrading enzyme activities . The order of degradation was as follows: positive and F systems > B system > negative and P systems . Therefore, fungal activity was responsible for most of the cell wall degradation . Cell wall degradation by the anaerobic bacterial fraction was significantly less than by the fungal fraction, and the protozoal fraction failed to grow under the conditions used . In general, in the mixed culture systems the coculture systems demonstrated a decrease in cellulolysis compared with that of the monoculture systems . When one microbial fraction was associated with another microbial fraction, two types of results were obtained . The protozoal fraction inhibited cellulolysis of cell wall material by both the bacterial and the fungal fractions, while in the coculture between the bacterial fraction and the fungal fraction a synergistic interaction was detected. Appl Environ Microbiol, 2000 Sep, 66(9), 3790 - 7 Rapid virus production and removal as measured with fluorescently labeled viruses as tracers; Noble RT et al.; Pelagic marine viruses have been shown to cause significant mortality of heterotrophic bacteria, cyanobacteria, and phytoplankton . It was previously demonstrated, in nearshore California waters, that viruses contributed to up to 50% of bacterial mortality, comparable to protists . However, in less productive waters, rates of virus production and removal and estimates of virus-mediated bacterial mortality have been difficult to determine . We have measured rates of virus production and removal, in nearshore and offshore California waters, by using fluorescently labeled viruses (FLV) as tracers . Our approach is mathematically similar to the isotope dilution technique, employed in the past to simultaneously measure the release and uptake of ammonia and amino acids . The results indicated overall virus removal rates in the dark ranging from 1.8 to 6.2% h(-1) and production rates in the dark ranging from 1.9 to 6.1% h(-1), corresponding to turnover times of virus populations of 1 to 2 days, even in oligotrophic offshore waters . Virus removal rates determined by the FLV tracer method were compared to rates of virus degradation, determined at the same locations by radiolabeling methods, and were similar even though the current FLV method is suitable for only dark incubations . Our results support previous findings that virus impacts on bacterial populations may be more important in some environments and less so in others . This new method can be used to determine rates of virus degradation, production, and turnover in eutrophic, mesotrophic, and oligotrophic waters and will provide important inputs for future investigations of microbial food webs. Appl Environ Microbiol, 2000 Sep, 66(9), 3680 - 5 Physiological and chemical investigations into microbial degradation of synthetic Poly(cis-1,4-isoprene); Bode HB et al.; Streptomyces coelicolor 1A and Pseudomonas citronellolis were able to degrade synthetic high-molecular-weight poly(cis-1,4-isoprene) and vulcanized natural rubber . Growth on the polymers was poor but significantly greater than that of the nondegrading strain Streptomyces lividans 1326 (control) . Measurement of the molecular weight distribution of the polymer before and after degradation showed a time-dependent increase in low-molecular-weight polymer molecules for S . coelicolor 1A and P . citronellolis, whereas the molecular weight distribution for the control (S . lividans 1326) remained almost constant . Three degradation products were isolated from the culture fluid of S . coelicolor 1A grown on vulcanized rubber and were identified as (6Z)-2,6-dimethyl-10-oxo-undec-6-enoic acid, (5Z)-6-methyl-undec-5-ene-2,9-dione, and (5Z,9Z)-6, 10-dimethyl-pentadec-5,9-diene-2,13-dione . An oxidative pathway from poly(cis-1,4-isoprene) to methyl-branched diketones is proposed . It includes (i) oxidation of an aldehyde intermediate to a carboxylic acid, (ii) one cycle of beta-oxidation, (iii) oxidation of the conjugated double bond resulting in a beta-keto acid, and (iv) decarboxylation. Crit Care Med, 2000 Aug, 28(8), 2949 - 55 Immune depression in polymicrobial sepsis: the role of necrotic (injured) tissue and endotoxin; Ayala A et al.; OBJECTIVE: Recent studies suggest immune dysfunction seen after the onset of polymicrobial sepsis, as produced by cecal ligation and puncture (CLP), is not caused by endotoxin (ETX) alone, but may be caused by the combined effect of the necrotic tissue (cecal ligation, {CL}) and other microbial components . Thus, the objective of this study was to assess the ability of necrotic tissue, in the presence or absence of low-dose endotoxin, to induce changes in the capacity of immune cells to produce proinflammatory or anti-inflammatory cytokines approximating those seen in CLP . DESIGN: Experimental, prospective study . SETTING: A hospital laboratory in the Center for Surgical Research . SUBJECTS: Male C3H/HeN mice . INTERVENTIONS: Mice were subjected to a CL and saline infusion (CL/Sal), CL in combination with low-dose ETX infusion (CL/ETX) (0.025 mg ETX/25 g body weight/24 hrs by a peritoneally implanted osmotic mini-pump), ETX infusion alone, saline infusion alone (Sal), CLP, or sham-CLP (Sham) . Splenocytes, splenic macrophage and peritoneal macrophage were harvested from these animals 24 hrs (late) after being subjected to the above protocols . Splenocyte and macrophage inducible cytokine release was assessed by ELISA/bioassay . Survival over a 7-day period was also examined in additional groups . MEASUREMENTS AND MAIN RESULTS: Our results indicate a marked decrease in splenic interleukin (IL)-2 . In addition, peritoneal or splenic macrophage IL-6 productive capacity was depressed in cells from animals subjected to CL/ETX or CLP . Alternatively, CL, in the presence or absence of ETX, induced a marked change in macrophage cytokine release capacity comparable to that seen in CLP, ie, decreased IL-12 release and increased IL-10 secretion . To the extent these cellular alterations contribute to an increase in mortality rate, we observed in subsequent survival studies that neither CL alone nor ETX produced mortality . However, the combination of CL/ETX markedly increased 7-day mortality rate (approximately 33%), although not to the same extent as CLP (80%) . CONCLUSIONS: These results collectively suggest that the response to devitalized tissue produced by cecal ligation may predispose the host to the induction of a suppressive macrophage phenotype . The subsequent exposure of these animals to microbial agents induces immune dysfunction, as well as mortality seen after such a polymicrobial septic challenge. J Biochem (Tokyo), 2000 Sep, 128(3), 415 - 25 Substrate specificity analysis of microbial transglutaminase using proteinaceous protease inhibitors as natural model substrates; Taguchi S et al.; The substrate specificity of microbial transglutaminase (MTG) from Streptomyces mobaraensis (formerly categorized Streptoverticillium) was studied using a Streptomyces proteinaceous protease inhibitor, STI2, as a model amine-donor substrate . Chemical modification and mutational analysis to address the substrate requirements for MTG were carried out around the putative reactive site region of STI2 on the basis of the highly refined tertiary structure and the solvent accessibility index of Streptomyces subtilisin inhibitor, SSI, a homolog of STI2 . The results suggest that the P1 reactive center site (position 70 of STI2) for protease subtilisin BPN' or trypsin may be the prime Lys residue that can be recognized by MTG, when succinylated beta-casein was used as a partner Gln-substrate . It is characteristic in that the same primary enzyme contact region of STI2 is shared by both enzymes, MTG and proteases . For quantitative analysis of the TG reaction, we established an ELISA-based monitoring assay system using an anti-SSI polyclonal antibody highly cross-reactive with STI2 . Site-specific STI2 mutants were prepared by an Escherichia coli expression-secretion vector system and subjected to the assay system . We reached several conclusions concerning the nature of the flanking amino acid residues affecting the MTG reactivity of the substrate Lys residue: (i) site-specific mutations from Asn to Lys or Arg at position 69 preceding the amine-donor 70Lys, led to enhanced substrate reactivity; (ii) amino acid replacement at 67Ile with Ser led to higher substrate reactivity, (iii) additive effects were obtained by a combination of the positive mutations at positions 67 and 69 as described above, and (iv) Gly at position 65 might be essential for MTG reaction . Moreover, the substrate specificity of guinea pig liver tissue transglutaminase (GTG) was compared with that of MTG using STI2 and its mutants . In contrast to MTG, replacement of Gly by Asp at position 65 was the most favorable for substrate reactivity . Also, 70Lys appeared not to be a prime amine-donor site for GTG-mediated cross-linking, suggesting a difference in substrate recognition between MTG and GTG. Immunol Lett, 2000 Jul 3, 73(1), 13 - 8 Beyond danger: unmethylated CpG dinucleotides and the immunopathogenesis of disease; Goldberg B et al.; Oligonucleotide sequences containing unmethylated cytidine phosphate guanosine (CpG) motifs are known to have significant immunostimulatory properties . Because of these immunostimulatory effects, unmethylated CpG oligonucleotides are thought to act as 'danger signals' that produce a favorable immune response by alerting the host to the presence of invading organisms or abnormal cells . In contrast to this concept, we review the evidence that unmethylated CpG sequences derived either from microbial agents or from endogenous CpG-rich Alu motifs promote disease progression by inducing an aberrant or autoreactive immune response . Recognition of the negative effect of unmethylated CpG dinucleotides should lead to more effective immune strategies to combat infectious, inflammatory, autoimmune and malignant diseases. Nature, 2000 Aug 17, 406(6797), 799 - 803 Microbial genome sequencing; Fraser CM et al.; Complete genome sequences of 30 microbial species have been determined during the past five years, and work in progress indicates that the complete sequences of more than 100 further microbial species will be available in the next two to four years . These results have revealed a tremendous amount of information on the physiology and evolution of microbial species, and should provide novel approaches to the diagnosis and treatment of infectious disease. Nature, 2000 Aug 17, 406(6797), 788 - 92 CD1-restricted T-cell responses and microbial infection; Park SH et al.; CD1, a conserved family of major histocompatibility (MHC)-like glycoproteins in mammals, specializes in capturing lipid rather than peptide antigen for presentation to T lymphocytes . The principles and mechanisms of this newly discovered immune strategy differ markedly from those governing classical MHC-peptide presentation . They might be exploited for the design of new lipid-based microbial vaccines and adjuvants. Blood, 2000 Sep 1, 96(5), 1633 - 7 Langerhans cells develop from a lymphoid-committed precursor; Anjuere F et al.; Langerhans cells (LCs) are specialized dendritic cells (DCs) strategically located in stratified epithelia, such as those of the skin, oral cavity, pharynx, esophagus, upper airways, urethra, and female reproductive tract, which are exposed to a wide variety of microbial pathogens . LCs play an essential role in the induction of T-lymphocyte responses against viruses, bacteria, and parasites that gain access to those epithelial surfaces, due to their high antigen capture and processing potential and their capacity to present antigen peptides to T cells on migration to the lymph nodes.(1) Although LCs have been classically considered of myeloid origin, recent reports, which demonstrate the existence of lymphoid DCs derived from multipotent lymphoid precursors devoid of myeloid differentiation potential,(2-5) raise the question of the lymphoid or myeloid origin of LCs . The present study shows that mouse lymphoid-committed CD4(low) precursors, with the capacity to generate T cells, B cells, CD8(+) lymphoid DCs, and natural killer cells,(26) also generate epidermal LCs on intravenous transfer, supporting the view that LCs belong to the lymphoid lineage . (Blood . 2000;96:1633-1637) J Neural Transm Suppl, 2000, 59, 59 - 68 The immunological microenvironment in the CNS: implications on neuronal cell death and survival; Neumann H; Microenvironmental factors have a profound influence on resident cell populations and their ability to modulate an immune response . The unique central nervous system (CNS) microenvironment has important effects in this regard, resulting in the establishment of immune privilege . The immune response in the CNS is under tight control of bipolar regulatory mechanisms . Neurons have a suppressive potential, which prevents and limits the formation of inflammatory responses . In contrast, activated lymphocytes, which can invade the CNS, deposit potentially pro-inflammatory mediators . The balance between pro- and anti-inflammatory factors determines localization, intensity and course of immune responses in the brain . Thus, an overwhelming invasion of activated lymphocytes, which may have emerged from a recent anti-microbial immune response, may create inflammation in intact parts of the CNS . In contrast, in compromised brain areas, much weaker proinflammatory forces are required to create the same effect . Thus, in degenerative brain lesions, inflammatory infiltrates may be formed easily . Immune cell invasion and expression of immune effector molecules in degenerative CNS disease could exert a variety of actions on the neurons . In the first instance, activation of the local immune response could be harmful to resident brain cells, possibly resulting in neuronal cell death . Alternatively, immune cell-derived mediators could protect and support the regeneration of damaged neurons . Recently, it has been realized that normal inflammatory cells (lymphocytes and macrophages) produce neurotrophic factors . In addition, pro-inflammatory cytokines released by invading immune cells may have a role in neuroprotection . Infiltration of degenerative brain areas by inflammatory cells could thus reflect a beneficial process encouraging neuronal survival and local cell regeneration. Br J Nutr, 2000 Jul, 84(1), 73 - 83 Effect of polyethylene glycol on in vitro degradability of nitrogen and microbial protein synthesis from tannin-rich browse and herbaceous legumes; Getachew G et al.; Determination of microbial degradability of N is important in formulating a sound supplementation strategy for efficient utilisation of basal as well as supplementary diet components . In vitro degradability of N (IVDN) from tannin-containing browses (Acacia cyanophylla, Acacia albida, Acioa barteri and Quercus ilex) and two herbaceous legumes (Desmodium intortum and Desmodium uncinatum) was determined using the in vitro gas-production method coupled with NH3-N measurement in the presence and absence of a tannin-binding agent (polyethylene glycol (PEG), molecular mass 6000) . Addition of PEG to tannin-containing feeds significantly (P < 0.05) increased in vitro gas and short-chain fatty acid (SCFA) production, and IVDN . The use of PEG as a tannin-binding agent increased IVDN from 28 to 59, 32 to 72, 19 to 40, 32 to 73, 40 to 80, and 26 to 77% in A . cyanophylla, A . albida, A . barteri, D . intortum, D . uncinatum and Q . ilex respectively . There was significant correlation between total phenolic compounds (total phenol, TP; total tannin, TT) in leguminous forages and percentage increase in IVDN on addition of PEG (P < 0.05; R2 0.70 and 0.82 for TP and TT respectively) . The difference in IVDN observed in the absence and presence of PEG indicates the amount of protein protected from degradation in the rumen by tannins . When measured after 24 h incubation, tannin-containing feeds incubated in absence of PEG resulted in higher microbial protein synthesis than in the presence of PEG . Addition of PEG significantly (P < 0.05) reduced the efficiency of microbial protein synthesis expressed as mumol purine/mmol SCFA. J Org Chem, 2000 Jul 28, 65(15), 4529 - 31 Chemoenzymatic synthesis of the microbial elicitor (-)-syringolide via a fructose 1,6-diphosphate aldolase-catalyzed condensation reaction; Chenevert R et al.; Syringolide 2, an elicitor of the bacterial plant pathogen Pseudomonas syringae pv . tomato which triggers a hypersensitive defense response in resistant soybean plants, has been synthesized in five steps via a fructose 1,6-diphosphate aldolase reaction. Scand J Infect Dis, 2000, 32(4), 399 - 402 Serum C-reactive protein cannot differentiate bacterial and viral aetiology of community-acquired pneumonia in children in primary healthcare settings; Heiskanen-Kosma T et al.; Whether serum C-reactive protein (CRP) can be used to distinguish bacterial from viral pneumonia was studied in 193 paediatric patients who were identified in a prospective, population-based study . The proportion of patients < 5 y of age was 51%, 53% of these and 12% of the older patients were treated in hospital . Pneumococcal aetiology of infection was studied in paired sera by antibody and immune-complex assays, and chlamydial, mycoplasmal and viral aetiologies by routine antibody assays . CRP concentration was measured by immunoturbidometry . Pneumococcal infection (mixed infections with other agents included) was present in 57 cases, mycoplasmal and/or chlamydial infection (pneumococcal infections excluded) in 43, and viral infection (pneumococcal, mycoplasmal and chlamydial infections excluded) in 29 cases . The mean CRP concentrations (95% confidence interval) in these groups were 26.8 mg/l (20.1-33.5 mg/l), 31.8 mg/l (20.5-33.1 mg/l) and 26.1 mg/l (19.1-33.1 mg/l), respectively, and 24.9 mg/l (18.8-31.0 mg/l) in patients with no aetiological findings . When CRP values were compared between the 2 diagnostic groups of pneumococcal infections (antibody and immune-complex positive) no difference was found . In infants < 12 months of age the mean CRP concentration was 14.6 mg/l, and in 11 (65%) of them it was unmeasurable (< 10 mg/l) . No significant differences were seen between hospitalized patients and outpatients . In conclusion, CRP concentration had no significant association with the microbial aetiology of pneumonia. J Microbiol Methods, 2000 Aug, 41(3), 249 - 57 Different methods for extracting bacteria from freshwater sediment and a simple method to measure bacterial production in sediment samples; dos Santos Furtado AL et al.; The efficiency of different treatments was tested to extract bacterial cells from freshwater sediment samples . The influence of sonication, density gradient centrifugation, fixation by formalin and centrifugation speed on bacterial recovery was investigated . The method developed by Smith and Azam {Mar . Microb . Food Webs 6 (1992) 107} to measure microbial activity on bacterioplankton (3H-leucine incorporation), was also evaluated in sediment samples . After 1 min of sonication bacterial abundance was reduced by about 47% in diluted sediments with tetrasodium pyrophosphate . With the addition of Percoll after sonication, bacterial counts were not significantly different (P<0.05) . Fixation by formalin increased bacterial counts using sonication . However, higher bacterial abundance was estimated in non-sonicated samples . Bacterial abundance in samples centrifuged at 7000xg with and without Percoll was not significantly different (P<0.05) . Highest bacterial abundance was obtained after centrifugation at low speed (750xg) . Bacterial abundance decreased with higher centrifugation speed (750, 1500 and 3000xg), the difference, however, was not significant . Bacterial production ranged from 0.10 microg C cm(-3) d(-1) in autoclaved sediment to 0 . 27 microg C cm(-3) d(-1) in untreated sediment . The radioactivity measured in controls of both untreated and autoclaved sediment was high (70 and 91%, respectively), indicating a high level of leucine adsorption in sediment particles . In contrast, radioactivity in control samples previously centrifuged was markedly lower (6%) . Despite the high values of radioactivity in the controls, bacterial production in untreated sediment was significantly higher than in centrifuged sediment (P<0.05). J Microbiol Methods, 2000 Aug, 41(3), 235 - 48 Measuring soil microbial community diversity using polar lipid fatty acid and denaturing gradient gel electrophoresis data; Hedrick DB et al.; The possibility of calculating useful microbial community diversity indices from environmental polar lipid fatty acid and 16S rDNA PCR-DGGE data was investigated . First, the behavior of the species richness, Shannon's, and Simpson's diversity indices were determined on polar lipid fatty acid profiles of 115 pure cultures, communities constructed from those profiles with different numbers of species, and constructed communities with different distributions of species . Differences in the species richness of these artificial communities was detected by all three diversity indices, but they were insensitive to the evenness of the distribution of species . Second, data from a field experiment with substrate addition to soil was used to compare the methods developed for lipid- and DNA-based diversity indices . Very good agreement was found between indices calculated from environmental polar lipid fatty acid profiles and denaturing gradient gel electrophoresis profiles from matched samples (Pearson's correlation coefficient r=0.95-0.96) . A method for data pre-treatment for diversity calculations is described. Appl Occup Environ Hyg, 2000 Aug, 15(8), 635 - 43 Resolution of sick building syndrome in a high-security facility; Hiipakka DW et al.; The main objective of this article is to serve as a case study for other industrial hygiene (IH) professionals' review as a "real world" effort in responding to a facility perceived as "sick" by its occupants . As many industrial hygienists do not have extensive backgrounds in evaluating microbial air contaminants or the mechanical function of building HVAC units, the overall intent is to provide "lessons learned" to IH generalists who may be asked to participate in indoor environmental quality (IEQ) surveys . In September 1994, a suspected case of "sick building syndrome" was investigated (with significant airborne fungal loads confirmed) at a communications center after numerous occupants reported upper respiratory disease and/or allergy-type symptoms . The setting was a two-story structure approximately 30 years old, with a normal occupancy load of 350 to 400 persons . In addition to continual structural modifications, the central HVAC air conditioning systems had poor maintenance histories . Inspection of HVAC components revealed visible fungal growth on air filters and air ducts and in cooling fan condensate drip pans . Fungal air samples were collected with an Anderson N6 air sampler and Sabouraund dextrose agar media . Over a study period of 23 months, three rounds of 26 air samples were collected for 5 minutes each at 28.3 liters/minute airflow . Cultures exhibited fungi such as Aspergillus, Penicillium, Alternaria, and Cladosporium . Certain strains of these fungi produce mycotoxins that may cause a variety of deleterious health effects such as those described by occupants . Initial 1994 airborne fungal concentrations ranged from 85 to 6157 colony forming units (CFUs) per cubic meter of sampled air (CFU/m3) . Some investigators have reported fungal concentrations as low as 245 CFU/m3 associated with complaint sites in other buildings . Remediation efforts involved hiring a dedicated mechanic to implement a HVAC preventive maintenance program (including regular replacement of all HVAC air filters and cleaning of accessible components with water/bleach solution) . Post-abatement January 1996 re-sampling revealed a significant drop in airborne fungal colonies up to 97 percent (range = 21 to 1092 CFUs/m3)--which also coincided with physicians at the local hospital sensing a qualitative reduction in patient visits from facility workers . To address seasonal bias, a final August 1996 air sample round revealed a range of 14 to 500 CFUs/m3 . Of the 21 workspaces sampled in all three rounds, nine continued to show a decline in CFUs/m3 from September 1994 baseline counts . These results demonstrate the critical role of an ongoing HVAC maintenance program for reducing potential reservoirs of fungal organisms in indoor work environments . Building renovations (especially those involving major changes to building layout and usage) can adversely affect IEQ if plans do not include coordinated updates and regular preventive maintenance of HVAC systems . Eventual negative outcomes can be reduced occupant productivity and deleterious health effects. Semin Neonatol, 2000 Aug, 5(3), 255 - 69 Sexually transmitted infections, adverse pregnancy outcome and neonatal infection; Moodley P et al.; Prevention and treatment of sexually transmitted infections (STIs) in the sexually active population are the main steps to prevent perinatal infection . However, the spread of STIs continues at an astronomical pace despite various attempts at controlling the epidemic . An important reason for this lack of STI control is that a large percentage of infected people go untreated because they have asymptomatic or unrecognized infections . The microbial differential diagnosis of STIs implicated in adverse pregnancy outcome is broad and includes viral, bacterial and protozoal infections . Infertility, ectopic pregnancy, pelvic inflammatory disease, chorioamnionitis, premature rupture of membranes, preterm birth and puerperal sepsis are some of complications seen in women as a result of infection with sexually transmitted pathogens . In addition, STIs may facilitate the acquisition and transmission of HIV . In the fetus or neonate, complications include abnormalities of the major organ systems . Infections in the form of pneumonia or conjunctivitis may also occur . Due to the lack of simple, inexpensive and sensitive point-of-care tests, screening for STIs in pregnancy is not performed routinely . J Agric Food Chem, 2000 Aug, 48(8), 3733 - 7 Triflusulfuron-methyl dissipation in water and soil; Vega D et al.; This paper reports laboratory studies of the behavior and fate of triflusulfuron-methyl in aqueous buffer and soils . Aqueous hydrolysis was pH-dependent and fast in acidic buffer solutions . In basic buffers, the hydrolysis rate variation was low between pH 7 and pH 10 . The degradation pathway in the range of pH 4-10 was via cleavage of the sulfonylurea bridge to form two transformation products: 2-amino-4-(dimethylamino)-6-(2,2,2-trifluoroethoxy)-1,3, 5-triazine (2) and 6-methyl-2-methylcarboxylate benzene sulfonamide (3) . Comparison of transformation rates in sterile and nonsterile soils indicates that chemical and microbial processes are important in soil degradation . The former is more important in acidic soils, and the latter is more important in basic soils . A biphasic model fits well with dissipation of triflusulfuron-methyl in soil . The triazine formed during the first step of transformation was degraded more rapidly in basic soils than in acidic soils. J Agric Food Chem, 2000 Aug, 48(8), 3292 - 7 Relationship between the glass transition of soy protein and molecular structure; Mizuno A et al.; The change in molecular structure of the soy protein samples as a result of the microbial transglutaminase treatment was studied using solid-state (13)C NMR spectroscopy and circular dichroism (CD), and the relation to the glass transition temperature (T(g)) was examined . From NMR measurements, the structure of the local region of the C(alpha) methine was observed to change, and the region had relatively high mobility . From CD measurements, the structural change seemed to be caused by the change in the secondary structure (disintegration of the beta-structure) . By comparison with the T(g) of another protein, the state of the secondary structure of a protein was suggested to be a key in determining its T(g). J Agric Food Chem, 2000 Aug, 48(8), 3286 - 91 Effect of transglutaminase treatment on the glass transition of soy protein; Mizuno A et al.; The effect of microbial transglutaminase (MTG) treatment on the glass transition temperature (T(g)) of two fractions which were isolated from a soy protein sample was studied . The T(g) of each fraction measured by differential scanning calorimetry was lowered by the MTG treatment, which generated cross-links in the samples, and this result agreed with the result of dynamic mechanical analysis . From the (1)H NMR measurement, the line width of the (1)H signal of the MTG-treated sample was observed to be greater than that of the MTG-nontreated sample at similar water content, which implied that there was relatively more immobilized water in the MTG-treated sample . The MTG treatment seemed to cause the increment in immobilized water, which might affect the T(g) of the soy protein sample. J Helminthol, 2000 Sep, 74(3), 203 - 8 In vitro interactions between epithelial cells and Gyrodactylus derjavini; Buchmann K et al.; Skin responses of fish to various parasites have been shown to involve various immunologically competent cells producing factors which guide the reactions of epithelial cells . However, the present study has demonstrated that a monoculture of epithelial cells has the ability to encapsulate and partially degrade ectoparasites without involvement of leukocytes . The ectoparasitic monogeneanGyrodactylus derjavini was kept on a monolayer of Epithelioma Papulosum Cyprini (EPC) cells in 24-well multidishes supplied with tissue culture medium . Gyrodactylus derjavini did not reproduce but survived an incubation period of up to139h in the system . Due to sterile conditions, dead gyrodactylids were not subjected to microbial degradation and remained intact for several weeks . However, at 40 days G . derjavini was overgrown by EPC-cells and became partly degraded during the following 15 days . Analysis of enzyme reactivity in EPC-cells showed reactions for ten enzymes including esterases, amidases, phosphatases and phosphohydrolases . No marked differences for the ten enzymes between cell cultures with and without the ectoparasites were found but it cannot be excluded that some of these enzymes took part in parasite degradation . The study showed the in vitro capability of epithelial cells to interact, encapsulate and degrade G . derjavini without the involvement of leukocytes . This response probably is non-specific and will not exclude that various immunocompetent cells and their products normally optimize and accelerate elimination of invading parasites in vivo. J Pathol, 2000 Sep, 192(1), 58 - 66 Expression patterns of E-cadherin, involucrin, and connexin gap junction proteins in the lining epithelia of inflamed gingiva; Ye P et al.; The structural integrity and functional differentiation of the lining epithelium were studied in relation to inflammatory changes associated with destructive periodontitis . In the different regions of lining epithelia from clinically healthy gingiva and periodontitis, comparisons were made of the expression patterns of E-cadherin, which is critical in intercellular adhesion; of proteins associated with gap junction communication channels; and of involucrin, which is a key marker of differentiation in stratified epithelia . Filamentous actin (F-actin), which is important in cell structural integrity, attachment, and migration, was also examined . Semiquantitative immunohistochemical analysis revealed that in both clinically healthy gingiva and lesions of advanced periodontitis, expression patterns of E-cadherin, involucrin, and connexins 26 and 43 were similar, with a statistically significant reduction in staining intensity from the external oral epithelium, through the gingival sulcus, to the junctional epithelium or pocket epithelium, respectively . Furthermore, there was a striking reduction in staining for E-cadherin, involucrin, and both connexins in the pathological lining epithelium of the periodontal pocket . These changes were associated with marked alterations of filamentous actin expression, collectively indicating profound perturbation of the epithelial structure . The data reported support the concept that the ability of the pathological lining epithelium to function as an effective barrier against the ingress of microbial products into the tissues is severely compromised . Microbiol Res, 2000 Jul, 155(2), 107 - 12 The development of fungi as affected by pH and type of soil, in relation to the occurrence of bacteria and soil fungistatic activity; Weyman-Kaczmarkowa W et al.; A study was made on the effect of liming (Ca(OH)2) on the numbers of colony-forming units (CFU) and the biomass of fungi in loamy sand (ls) and a loose sandy soil (lss) during 90 days under laboratory conditions . Liming inhibited the growth of fungi more strongly in the lighter soil . Raising the pH of lss from its native 4.5 to 7.0 and 9.0 decreased mean fungal CFU numbers by 50%, and their biomass by 42% and 68%, respectively, in comparison with control unlimed samples . Also in ls with its native pH of 7.7, when alkalinised to 9.0 and 11.0 the fungal CFU numbers were smaller than in the control by 25% and 50%, respectively, and the fungal biomass decreased by 40% and 56%, respectively . Although in a parallel research alkalinisation has been shown to stimulate bacterial growth very strongly, especially in lss, the total microbial biomass (fungal + bacterial) declined by an average of 30% (pH 9.0) and 40% (pH 11.0) in limed ls, and by 35% (pH 7.0) and as much as 50% (pH 9.0) in lss, in comparison with the control. Microbiol Res, 2000 Jul, 155(2), 87 - 94 Fe(III) reduction activity and cytochrome content of Shewanella putrefaciens grown on ten compounds as sole terminal electron acceptor; Blakeney MD et al.; Shewanella putrefaciens was grown on a series of ten alternate compounds as sole terminal electron acceptor . Each cell type was analyzed for Fe(III) reduction activity, absorbance maxima in reduced-minus-oxidized difference spectra and heme-containing protein content . High-rate Fe(III) reduction activity, pronounced difference maxima at 521 and 551 nm and a predominant 29.3 kDa heme-containing protein expressed by cells grown on Fe(III), Mn(IV), U(VI), SO3(2-) and S2O3(2-), but not by cells grown on O2, NO3, NO2-, TMAO or fumarate . These results suggest that microbial Fe(III) reduction activity is enhanced by anaerobic growth on metals and sulfur compounds, yet is limited under all other terminal electron-accepting conditions. Eur J Gynaecol Oncol, 2000, 21(3), 273 - 7 Analysis of the DNA "mismatch-repair" enzyme human mut-S-homologon-2 in endometrial cancer on protein- and RNA-level; Friedrich M; BACKGROUND: Microsatellite instability seems to be important in the development of various human cancers including sporadic endometrial cancer and is characterized by length changes at repetitive loci scattered throughout the genome . It has been shown that cancer predisposition is attributable to defects in any one of four genes, all of which encode homologs of the microbial mismatch repair proteins mutS and mutL.The human Mut-S-Homologon-2 gene (hMSH-2) specifies a mutS homolog, whereas hMLH-1, hPMS-1 and hPMS-2 encode homologs of mutL . MATERIAL AND METHODS: Freshly excised endometrial specimens (malignancies of the uterine corpus: n=50; normal endometrial tissue: n=20) were examined by immunohistochemistry (mAb FE 11, Dianova, Germany) and RT-PCR to analyze the expression of human MUT-S-Homologon-2 on protein- and mRNA-level . Most of the neoplasms of the uterine corpus were sporadic endometrial . RESULTS: In the immunohistochemical study, 25% of normal endometrial tissues were human Mut-S-Homologon-2 negative, while the remaining 75% revealed weak human Mut-S-Homologon-2 immunoreactivity (mean human Mut-S-Homologon-2 IRS: 1.52; SD: +/-1.42; mean human Mut-S-Homologon-2-PP: 12.12; SD: +/-10.31; mean human Mut-S-Homologon-2 IS: 0.98; SD: +/-0.81) . All malignancies of the uterine corpus revealed strong nuclear immunoreactivity for human Mut-S-Homologon-2 (mean human Mut-S-Homologon-2-IRS: 9.12, SD: +/-3.34; mean human Mut-S-Homologon-2-PP: 81.82, SD: +/-15.67; mean human Mut-S-Homologon-2-IS: 2.58, SD: +/-0.71) . In addition, expression of human Mut-S-Homologon-2 protein was statistically significantly upregulated in tumor cells of malignancies of the uterine corpus as compared to normal endometrial tissue on the protein level . In the RT-PCR study, the hMSH-2 gene was highly expressed in endometrial neoplasms on the mRNA-level . hMSH-2 expression was consistently increased in endometrial neoplasms compared to normal endometrial tissue . CONCLUSION: The expression of the human MUT-S-Homologon-2 is increased both on the protein- and on mRNA-level in endometrial neoplasms compared to normal endometrial tissue possibly caused by the neoplastic process driven by an increase in the rate of mutations in oncogenes and tumor suppressor genes. Akush Ginekol (Sofiia), 2000, 39(2), 32 - 3 {The microbial findings in leukorrhea}; Shopova E; During two periods /1984/86 and 1998/01.00/ were studied microbial findings from vaginal specimens of women in reproductive age /16-48/ . Candida spp . was isolated most frequently /17.3% to 21.5%/ . BV was increased from 4.6% to 13.1% . T . vaginalis was decreased from 8.7% to 1.8%, probably as a consequence of metronidazole appliance. Infect Immun, 2000 Sep, 68(9), 5420 - 4 Prevotella intermedia stimulates expansion of Vbeta-specific CD4(+) T cells; Leung KP et al.; Recent evidence suggests that certain periodontal pathogens preferentially stimulate T cells expressing specific variable regions on the beta chain (Vbeta) of the T-cell receptor, which may indicate the presence of a superantigen . Superantigens are microbial proteins that activate large numbers of CD4(+) T cells in a Vbeta-specific manner . The purpose of this study was to determine whether Prevotella intermedia, a putative periodontal pathogen, activates populations of specific Vbeta on CD4(+) T cells . Among the bacterial strains tested, P . intermedia strain 17, a clinical isolate, induced the strongest proliferative response in peripheral blood mononuclear cells . Antibodies raised against whole cells of this organism blocked the proliferative activity . P . intermedia-induced proliferation was T-cell specific and required the presence of antigen-presenting cells . Flow cytometric analysis showed that CD4(+) T-cell subsets expressing Vbeta8, Vbeta12, and Vbeta17 expanded in response to P . intermedia strain 17 . The ability of P . intermedia to stimulate CD4(+)-T-cell proliferation was further supported by the production profiles of key T-cell cytokines, gamma interferon and interleukin-2 . The data collectively suggest that certain strains of P . intermedia can activate Vbeta-specific T cells in a manner similar to that of other known microbial superantigens. Immunol Cell Biol, 2000 Aug, 78(4), 318 - 24 Interaction of dendritic cells with mycobacteria: where the action starts; Demangel C et al.; Dendritic cells (DC) are the major antigen-presenting cells in the induction of cellular responses to intracellular pathogens, such as mycobacteria . Recent studies have shown that they also play a critical role in the regulation of immune responses . The interaction of DC with microbial antigens may be the controlling factor in the development of a Th1-orientated protective immunity . Analysis of the innate response of DC to mycobacteria and the involvement of the DC receptors in antigen recognition have highlighted the pivotal role of these cells in T-cell activation . Mycobacteria-infected DC have an enhanced capacity to release pro-inflammatory cytokines and chemokines and are potent inducers of interferon-gamma-producing cells in vivo . Therefore, DC manipulation for maximal antigen presentation and Th1 cytokine production may form the basis of a new generation of vaccines, with improved efficacy against mycobacterial infections. J Anim Sci, 2000 Aug, 78(8), 2150 - 6 Limiting order of amino acids and the effects of phytase on protein quality in corn gluten meal fed to young chicks; Peter CM et al.; An amino acid deletion assay, a protein efficiency ratio (PER) assay, and a slope-ratio growth assay were used to establish the limiting order of AA, and to determine the effects of microbial phytase on protein utilization in corn gluten meal (CGM) fed to chicks during the period of 8 to 21 d posthatching . In Assay 1, a 12% CP CGM diet was fortified with AA to fulfill the digestible AA ideal profile (only Phe + Tyr, Leu, and Pro exceeded requirements) for young chicks . Amino acids were then individually deleted, and all diets were fortified to 23% CP, with Glu varying as necessary . A Met-fortified 23% CP corn-soybean meal diet served as a positive control . No weight gain or feed efficiency differences were observed between the fully fortified CGM basal diet and the corn-soybean meal positive-control diet . The limiting order of AA established in CGM was 1) Lys, 2) Trp, 3) Arg, 4) Thr, 5) Val, 6) Ile, 7) His, 8) cystine, and 9) Met . In Assay 2, diets with 10% CP furnished by CGM or casein were fed in the presence and absence of 1,200 U/kg phytase . A protein source x phytase interaction (P < 0.05) was observed for weight gain, gain:feed, and PER, indicating positive responses to phytase when casein was fed but negative responses to phytase when CGM was fed . In Assay 3, graded levels of protein (8, 16, and 24% CP) furnished by CGM were fed in the presence and absence of 1,200 U/kg phytase . Weight gain and gain:feed increased linearly (P < 0.05) as a function of protein intake, but phytase supplementation had no effect on weight gain or gain:feed slopes . These results indicate that 1,200 U/kg phytase did not increase either CP or AA utilization in CGM for young chicks. Proc Nutr Soc, 2000 May, 59(2), 209 - 14 New perspectives on the use of tropical plants to improve ruminant nutrition; Teferedegne B; Inadequate nutrition is the main cause of low productivity by ruminants in sub-Saharan Africa . The primary feed resources in the region include natural pasture and crop residues that have tough texture, poor digestibility and are deficient in nutrients . These deficiencies can be corrected by supplementation with high-density feeds such as oilseed cakes and proteins of animal origin . However, protein sources such as oilseed cakes are beyond the economic reach of most farmers, while the incidence of bovine spongiform encephalopathy in Western intensive animal production may be thought to argue against the use of animal proteins . Local tree legumes have been investigated as potential supplements for ruminants because of their beneficial effect of increasing metabolizable energy intake, N intake and feed efficiency, and improving animal performance . However, our work has suggested that some plant materials may have a nutritional value beyond simply their nutrient content, i.e . as rumen-manipulating agents . The foliage of some tree legumes has been shown to be selectively toxic to rumen protozoa . Rumen protozoa ingest and digest bacteria and fungi, degrading their cellular protein to NH3 . Microbial protein turnover due to protozoal predation in the rumen may result in the net microbial protein outflow being less than half the total protein synthesized . Results from in vivo experiments have clearly shown that duodenal flow of both undegraded dietary and bacterial protein is generally increased by defaunation . However, no practical method has been developed to date to eliminate protozoa . Anti-protozoal plants may be promising, safe, natural defaunating agents. Proc Nutr Soc, 2000 May, 59(2), 177 - 85 Early nutrition and the development of immune function in the neonate; Kelly D et al.; The present review will concentrate on the development of the gut-associated lymphoid tissue and the role of early nutrition in promoting immune function . The intestine is the largest immune organ in the body, and as such is the location for the majority of lymphocytes and other immune effector cells . The intestine is exposed to vast quantities of dietary and microbial antigens, and is the most common portal of entry for pathogens, some of which are potentially lethal . The development of normal immune function of the intestine is therefore vital for survival, and is dependent on appropriate antigen exposure and processing, and also an intact intestinal barrier . In early life innate mechanisms of defence are probably more important than active or adaptive mechanisms in responding to an infectious challenge, since the healthy neonate is immunologically naive (has not seen antigen) and has not acquired immunological memory . During this period maternal colostrum and milk can significantly augment resistance to enteric infections . The mechanisms of enhancing disease resistance are thought to be passive, involving a direct supply of anti-microbial factors, and active, by promoting the development of specific immune function . A tolerance response to dietary and non-invasive antigens is generally induced in the gut . However, it must also be able to mount an adequate immune response to ensure clearance of foreign antigens . It is now recognized that regulation of tolerance and active immune responses is critical to health, and failure to regulate these responses can lead to recurrent infections, inflammatory diseases and allergies . The education of the immune system in early life is thought to be critical in minimizing the occurrence of these immune-based disorders . During this phase of development maternal milk provides signals to the immune system that generate appropriate response and memory . One factor that has been proposed to contribute to the increase in the incidence of immune-based disorders, e.g . atopic diseases in Western countries, is thought to be the increased prevalence of formula-feeding. Med Device Technol, 2000 Apr, 11(3), 12 - 6 A potential method for the specification of microbial barrier properties; Scholla MH et al.; A microbial barrier test to determine the barrier characteristics of porous packaging materials has been developed that will allow real-time testing in manufacturing environments . None of the barrier challenge tests used to date have achieved universal acceptance and they have taken days to perform . The new physical test means that quality control can be conducted on the manufacturing line in 10 minutes . The findings of tests conducted on porous barrier materials are reported. J Appl Microbiol, 2000 Jul, 89(1), 178 - 84 Determination of metabolic activity of streptomycetes in soil microcosms; Katsifas EA et al.; Two Streptomyces griseus strains were isolated from different soil types . S . griseus CAG17 strain was isolated from an agricultural area with low organic matter but rich in phosphorus content and S . griseus 26K strain was isolated from a forest area rich in organic matter with a low phosphorus content . The survival and metabolic activity of these isolates were studied in dynamic sterile soil microcosm systems . The fitness of each isolate was studied by re-inoculation in a soil type different from its origin . Maximum percentage of germination and respiration rates occurred within the first 48 h after each soil turnover (removal and addition of certain soil volumes) . Data suggested that S . griseus CAG17 survived better independently of the soil type in comparison with S . griseus 26K which sporulated within the first 12 h after inoculation . Incubation temperatures did affect the lifecycles in relation to soil type . For example, the lowest temperature tested, 22 degrees C, was more favourable for extended germination and adaptation in general but revealed lesser spore numbers in the 'foreign' soil environment . Monitoring metabolic activity by estimation of urease, phosphatases and dehydrogenase-specific activities, between 18 and 35 degrees C incubation temperatures, was a reliable method for studying the survival and growth of streptomycete populations in soil . Results also confirmed that respiration rate and enzyme-specific activity corresponded with spore counts in long-term experiments which were designed for the investigation of survival and growth of S . griseus CAG17 . Under selective pressure by heavy metals, in soil microcosm systems, metabolic activity proved a useful tool for the investigation of streptomycete activity . These methods could also be applied in agricultural field studies for monitoring microbial populations under conditions where various 'pollutants' are present in soil samples. J Infect Dis, 2000 Sep, 182 Suppl 1, S134 - 8 Micronutrients and infection: interactions and implications with enteric and other infections and future priorities; Guerrant RL et al.; Symposium presentations have focused on the elegant molecular science and the biologic mechanisms by which micronutrients play critical roles in cellular and humoral immune responses, cellular signaling and function, and even in the evolution of microbial virulence . The concluding session examined the practical issues of how best to evaluate the nutritionally at-risk host, especially in the areas of greatest need-an analytical model of nutrient-immune interactions, implications of nutritional modulation of the immune response for disease, and the implications for international research and child health . This overview illustrated how malnutrition may be a major consequence of early childhood diarrhea and enteric infections, as enteric infections may critically impair intestinal absorptive function with potential long-term consequences for growth and development . The potentially huge, largely undefined DALY (disability-adjusted life years) impact of early childhood diarrheal illnesses demonstrates the importance of quantifying the long-term functional impact of largely preventable nutritional and infectious diseases, especially in children in developing areas. J Exp Bot, 2000 Aug, 51(349), 1449 - 57 Effect of nitrogen supply and defoliation on loss of organic compounds from roots of Festuca rubra; Paterson E et al.; The aim of this study was to determine the effects of N-supply and defoliation on rhizodeposition from Festuca rubra, in the context of whole-plant C- partitioning and root morphology . Plants were grown for 36 d in axenic sand microcosms continuously percolated with nutrient solutions of either high or low N concentration (2 mM or 0.01 mM NH(4)NO(3), respectively) . The effects of partial defoliation at weekly intervals were determined at high and low N . At low N, dry matter accumulation in roots and shoots was reduced significantly (P<0.001), with proportionately increased partitioning to roots, in comparison with the high N treatment . Root morphology was also affected by N-treatment; at low N, lower biomass production was offset by increased specific root length (P<0.001), reducing the magnitude of the significant (P=0.002) increase in total root length at high N . Cumulative release of organic C from roots of F: rubra over the experimental period was not altered significantly by N-treatment . However, as a proportion of net C-assimilation, rhizodeposition was significantly (P<0.001) greater at low N than at high N . Defoliation transiently (3-5 d) increased the release of soluble organic compounds from roots at each N-supply rate, and increased significantly (P<0.001) cumulative rhizodeposition over the experimental period . These effects of N-supply and defoliation on rhizodeposition are of importance in understanding interactions between plant and microbial productivity in grazed grasslands, and in interpretation of concurrent effects on microbially driven nutrient cycling processes in these systems. Baillieres Best Pract Res Clin Haematol, 2000 Jun, 13(2), 301 - 17 Eosinophilia and helminthic infections; Leder K et al.; Among microbial agents, helminths are the most common cause of eosinophilia . An approach to the evaluation of a patient with eosinophilia is outlined, with particular emphasis on clues in the history, examination and routine laboratory data that can help with the diagnosis . Multiple helminthic infections have been associated with eosinophilia, and the characteristic modes of spread, clinical manifestations, diagnostic tests and therapeutic considerations of these infections are discussed . Eur J Immunol, 2000 Aug, 30(8), 2257 - 67 Regulation of type 2 nitric oxide synthase by type 1 interferons in macrophages infected with Leishmania major; Mattner J et al.; We recently reported that the infection of macrophages with Leishmania major led to the release of type 1 interferons (IFN-alpha /beta ) . Moreover, at day 1 of infection of mice with L . major, IFN-alpha /beta was required for the expression of type 2 (inducible) NO synthase (NOS2 or iNOS) which, however, was restricted to a few macrophages in the dermis . Here, we further characterized the regulation of NOS2 by IFN-alpha /beta . Macrophages that were either simultaneously or sequentially exposed to L . major promastigotes and IFN-alpha /beta expressed NOS2 and anti-leishmanial activity . In contrast, when high amounts of IFN-alpha /beta were used or when IFN-alpha /beta was added to the macrophages 2 h prior to the parasites, almost no induction of NOS2 was observed . After pretreatment with IFN-alpha /beta, tyrosine phosphorylation and nuclear DNA binding of Stat1alpha, the degradation of the NF-kappaB inhibitor (IkappaBalpha and beta), and the nuclear translocation of NF-kappaB were strongly impaired compared with macrophages exposed to IFN-alpha /beta and L . major simultaneously . Thus, IFN-alpha /beta exerts agonistic or antagonistic effects on the expression of NOS2 in macrophages infected with a microbial pathogen, depending on the sequence of the stimuli and the amount of IFN-alpha /beta added . The limited number of NOS2-positive macrophages at day 1 of infection in vivo might result from a blockage of non-infected macrophages by IFN-alpha /beta that is released by neighboring infected cells. Surg Neurol, 2000 Jun, 53(6), 605 - 10 Nocardia asteroides cerebral abscess in immunocompetent hosts: report of three cases and review of surgical recommendations; Fleetwood IG et al.; BACKGROUND: Nocardia asteroides cerebral abscesses are rare intracranial lesions . They account for only 2% of brain abscesses . Existing literature takes the form of anecdotal reports, small case series, and retrospective studies . An optimal treatment approach has not been established . However, there is evidence that the size of the lesion and clinical and immune status of the patient are relevant to surgical decision making . METHODS: Three recent cases are presented and the existing literature is reviewed . RESULTS: The outcome in all three cases was satisfactory . Although the currently recommended neurosurgical management protocols were followed, one patient had a prolonged course, which may have been shortened had an earlier biopsy of the cerebral lesion been performed . CONCLUSIONS: The surgical approach to suspected Nocardia spp . cerebral abscesses has recently become less aggressive . A more aggressive approach than that currently preferred for suspected Nocardia spp . cerebral abscesses may be appropriate . Earlier biopsy of lesions to achieve specific identification and anti-microbial sensitivity profiles is suggested even in cases where an extracranial focus of infection is found . Delays in obtaining a biopsy may lead to non-specific or unhelpful results that may prolong the course in hospital and jeopardize the outcome. Angew Chem Int Ed Engl, 2000 Jul 3, 39(13), 2206 - 2224 New Syntheses with Oils and Fats as Renewable Raw Materials for the Chemical Industry; Biermann U et al.; Oils and fats are the most important renewable raw materials for the chemical industry . Hitherto, industrial oleochemistry has concentrated predominantly on the carboxy functionality of fatty acids but, more recently, modern synthetic methods have been applied extensively to fatty compounds for the selective functionalization of the alkyl chain . Radical, electrophilic, nucleophilic, and pericyclic as well as transition metal catalyzed additions to the C-C double bond of, for example, oleic acid as the prototype of a readily accessible, unsaturated fatty acid have led to a large number of novel fatty compounds from which interesting properties are expected . Functionalization of C-H bonds in the alkyl chain is also feasible with remarkable selectivity . Effective and highly versatile catalysts for the metathesis of esters of unsaturated fatty acids have been developed, which lead to new and interesting omega-unsaturated fatty acids . The epoxidation of unsaturated fatty acids has been developed extensively . Enzymatic reactions allow syntheses with high selectivity and yield of mono- and diglycerides and esters of carbohydrates with a variety of surfactant properties . Regio- and enantioselective microbial hydrations and hydroxylations widen the spectrum of selective reactions . Of considerable significance is that, with the use of gene technology, natural oils and fats have been improved significantly and will be improved still further, insofar as they show a more uniform and often unusual fatty acid spectrum . Numerous fatty acids are now available in a purity which makes them attractive for synthesis and as raw materials for the chemical industry. Int J Syst Evol Microbiol, 2000 Jul, 50 Pt 4, 1441 - 7 Thiocapsa litoralis sp . nov., a new purple sulfur bacterium from microbial mats from the White Sea; Puchkova NN et al.; A new phototrophic purple sulfur bacterium, isolated from benthic microbial mats from the White Sea littoral zone, is described . Individual cells were spherical, non-motile and lacked gas vesicles . In pure cultures cells appeared in regular platelet-like arrangements of four, eight or sixteen cells . Cell division occurred inside a common envelope, surrounded by a thick capsule . Internal photosynthetic membranes were of the vesicular type . The colour of cell suspensions was pink to rose-red . Bacteriochlorophyll a and carotenoids of the spirilloxanthin series were found as photosynthetic pigments . Under anoxic conditions in the light, photolithoautotrophic growth occurred with sulfide, thiosulfate, sulfite and elemental sulfur as electron donors . Sulfur globules were stored as an intermediary oxidation product and were visible microscopically inside the cells . In the presence of sulfide and bicarbonate, photomixotrophic growth occurred with a number of organic substrates . Sulfate could serve as sole assimilatory source of sulfur . Chemolithoautotrophic growth in the dark was possible with sulfide and thiosulfate as electron donors . Optimum growth occurred in the presence of 1% NaCl, at pH 6.5 and at 30 degrees C . The DNA base composition of the type strain, BM5T, was 64.0 mol% G+C . According to 16S rDNA sequence information and DNA-DNA hybridization, the new isolate clearly belongs to the genus Thiocapsa, but is sufficiently different from other recognized Thiocapsa species to be described as a new species of this genus for which the name Thiocapsa litoralis sp . nov . is proposed . The type strain is BM5T (= ATCC 700894). Int J Food Microbiol, 2000 Jul 15, 58(3), 213 - 21 Sensitivity analysis in quantitative microbial risk assessment; Zwieterin MH et al.; The occurrence of foodborne disease remains a widespread problem in both the developing and the developed world . A systematic and quantitative evaluation of food safety is important to control the risk of foodborne diseases . World-wide, many initiatives are being taken to develop quantitative risk analysis . However, the quantitative evaluation of food safety in all its aspects is very complex, especially since in many cases specific parameter values are not available . Often many variables have large statistical variability while the quantitative effect of various phenomena is unknown . Therefore, sensitivity analysis can be a useful tool to determine the main risk-determining phenomena, as well as the aspects that mainly determine the inaccuracy in the risk estimate . This paper presents three stages of sensitivity analysis . First, deterministic analysis selects the most relevant determinants for risk . Overlooking of exceptional, but relevant cases is prevented by a second, worst-case analysis . This analysis finds relevant process steps in worst-case situations, and shows the relevance of variations of factors for risk . The third, stochastic analysis, studies the effects of variations of factors for the variability of risk estimates . Care must be taken that the assumptions made as well as the results are clearly communicated . Stochastic risk estimates are, like deterministic ones, just as good (or bad) as the available data, and the stochastic analysis must not be used to mask lack of information . Sensitivity analysis is a valuable tool in quantitative risk assessment by determining critical aspects and effects of variations. Int J Food Microbiol, 2000 Jul 15, 58(3), 147 - 57 Hazard identification and exposure assessment for microbial food safety risk assessment; Lammerding AM et al.; The four cornerstones of microbial food safety risk assessment are hazard identification, exposure assessment, hazard characterization, and risk characterization . These steps represent a systematic process for identifying adverse consequences and their associated probabilities arising from consumption of foods that may be contaminated with microbial pathogens and/or microbial toxins . This paper presents a discussion of the first two steps: hazard identification and exposure assessment, and considerations for different approaches that can be used to analyze the relevant information. Vox Sang, 2000, 78 Suppl 2, 67 - 70 Old and new tests: where will it end? Holland PV. Testing has improved the safety of the blood supply . We have excellent serologic tests in place now and are implementing nucleic acid based tests to identify asymptomatic carriers of viruses during the infectious part of the pre-seroconversion (window) period . However, the blood supply was already quite safe after a variety of other mechanisms had been put into place besides testing to screen out individuals at risk of carrying the most important transfusion transmissible agents . An important safety factor is the use of volunteer, unpaid (unremunerated) blood donors . The best alternative to implementing yet more tests to reduce, but not eliminate, the minute residual risks of transfusion transmission of such agents as HIV, HBV and HCV is the application of microbial inactivation technology to blood and blood components . Such microbially inactivated, cellular blood components should not have the risk of transmitting infectious agents, but may have other, different risks, since nothing has yet been shown to be one hundred percent safe (i.e., risk free) . The use of a test to detect carriers of spongiform encephalopathies to prevent their theoretical transmission by transfusion may cause harm to donors and might increase risk for recipients by decreasing the available blood supply. Fish Shellfish Immunol, 2000 Feb, 10(2), 167 - 86 Biochemical and functional characterisation of macrophage stimulating factors secreted by mitogen-induced goldfish kidney leucocytes; Neumann NF et al.; Mitogen-stimulated goldfish kidney leucocytes secrete a number of different macrophage activation factors (MAF) that induce profound physiological changes in macrophages . MAF produced by goldfish kidney leucocytes was characterised using fast performance liquid chromatography (FPLC) and bioassays that measured MAF-induced respiratory burst (RB) and nitric oxide (NO) responses of activated macrophages . Mitogen-induced fish kidney leucocyte supernatants were fractionated using gel permeation FPLC (GP-FPLC) and the ability of different fractions to induce NO or RB measured . A MAF of M(r) 50 kD, that induced a potent nitric oxide response in both a long-term goldfish macrophage cell line (GMCL) and in in vitro-derived fish kidney macrophages (IVDKM) was identified . The GP-FPLC partially purified 50 kD MAF activity occasionally induced significantly higher nitric oxide production than that of the crude MAF preparations . This increase in the NO-inducing activity was due to segregation of the 50 kD MAF from a novel macrophage deactivating molecule of M(r) 10-12 kD present in crude MAF preparations . This 10-12 kD molecule was shown to inhibit nitric oxide production in cytokine-activated goldfish macrophages . Mitogen-induced fish kidney leucocyte supernatants contained two distinct MAFs that induced the respiratory burst in GMCL and IVDKM: the 50 kD and 30 kD proteins . The partially purified 30 kD MAF primed goldfish macrophage for increased RB activity after only 6 h of treatment, and continued to augment the RB activity after 24 h of stimulation . In contrast, the GP-FPLC partially purified 50 kD molecule also primed the RB after only 6 h of stimulation, but subsequently deprimed the RB after 24 h of stimulation, an effect similar to that observed for crude MAF preparations . The 50 kD MAF activity was further purified using chromatofocusing FPLC (C-FPLC) using basic pH gradients and was shown to consist of two distinct NO-inducing molecules (> pI 9.3) . Mitogen-stimulated fish kidney leucocytes secrete several factors that profoundly affect the anti-microbial responses of teleost macrophages and which undoubtedly are responsible for regulating teleost macrophage function in vivo. Fish Shellfish Immunol, 2000 Jan, 10(1), 1 - 20 Generation and functional analysis of distinct macrophage sub-populations from goldfish (Carassius auratus L.) kidney leukocyte cultures; Neumann NF et al.; Three distinct sub-populations of macrophages derived from goldfish kidney leukocyte cultures were generated and characterised . The sub-populations designated as R1, R2 and R3-type macrophages had distinct morphological, cytochemical and flow cytometric profiles, and also differed in their anti-microbial functions after activation with macrophage activation factors (MAF) and bacterial lipopolysaccharide (LPS) . The R1-type macrophages were small cells that contained acid phosphatase, but lacked myeloperoxidase and non-specific esterase . The R2-type macrophages were morphologically similar to mature tissue macrophages of mammals, and were positive for acid phosphatase, myeloperoxidase and non-specific esterase . The R3-type macrophages were round cells with eccentrically placed nuclei and resembled mammalian monocytes . This sub-population stained for acid phosphatase, myeloperoxidase and non-specific esterase . The R2 and R3-type macrophages exhibited distinct functional responses after activation with MAF and/or LPS . R2-type macrophages were potent producers of nitric oxide, while R3-type macrophages produced little or no nitric oxide after activation with MAF and LPS . The R2 and R3-type macrophages also exhibited unique respiratory burst responses (ROI) after treatment with MAF and/or LPS . After treatment with MAF and LPS, activated R2 macrophages were primed for ROI after only 6 h of stimulation with the activating agents, and continued to exhibit a strong ROI response for an extended cultivation period (48 h) . In contrast, activated R3-type macrophages showed an early ROI response (6 h after treatment with MAF and LPS), which decreased significantly by 48 h after treatment with the activating agents . Our results suggest that the analysis of the mechanisms of induction of fish anti-microbial responses may be dependent upon the concerted actions of functionally distinct macrophage sub-populations. Metab Eng, 2000 Apr, 2(2), 140 - 8 Metabolic flux analysis in Streptomyces coelicolor under various nutrient limitations; Naeimpoor F et al.; Metabolic flux analysis was applied to Streptomyces coelicolor continuous culture data obtained under nitrogen, phosphate, sulfate, and potassium limitations . The metabolic reaction network involved more than 200 reactions describing the major pathways as well as the secondary metabolism for the production of actinorhodin and excretion of certain metabolites . Linear programming was used for the optimization of specific growth rates and energy requirements . Two types of specific growth rates, stoichiometric and theoretical, were defined, maximized, and compared in order to investigate the microbial potential . Potassium limitation led to the largest and nitrogen limitation to the smallest difference between the stoichiometric and theoretical specific growth rates . Although the value of the maximum theoretical specific growth rate was close to that of the experimental specific growth rate with potassium limitation, this difference was the largest in the case of nitrogen limitation . Energy requirements during different nutrient limitations were also investigated . The model indicated that although the highest actinorhodin production rate was with nitrogen limitation, this was accompanied with the undesired excretion of certain metabolites. Mol Biotechnol, 1999 Dec 1, 13(2), 89 - 111 Basic problems of serological laboratory diagnosis; Fierz W; Serological laboratory diagnosis is inflicted with at least two kinds of basic problems . One type relates to the fact that the serological diagnosis of infectious diseases is double indirect: First, to diagnose an infectious disease, the identification of the microbial agent is sought that caused the disease . Second, to identify this infectious agent, the patient's immune response to potential agents is measured . So, the serological test is neither measuring directly disease nor the cause of the disease, but the patient's immune system . Another type of problem is based on the fact that each person's immune system is very individual . The exact physicochemical properties of antibodies are unique for each clone of antibodies . The way an individual's immune system sees an infectious agent depends not only on the genetic makeup of the person but also on the personal experience from former encounters with infectious agents . Both types of problems lead to complexities in selecting the appropriate test, in interpreting the results, and in standardizing serological tests . Therefore, a close collaboration of the laboratory with the clinic is mandatory to avoid erroneous conclusions from serological test results, which might lead to wrong decisions in patient care. Anal Biochem, 2000 Aug 15, 284(1), 125 - 35 Synthesis and applications of stereospecifically (3)H-labeled arachidonic acids as mechanistic probes for lipoxygenase and cyclooxygenase catalysis; Schneider C et al.; Stereospecifically (3)H-labeled substrates are useful tools in studying the mechanism of hydrogen abstractions involved in the oxygenation of polyunsaturated fatty acids . Here, we describe modified methods for the synthesis of arachidonic acids labeled with a single chiral tritium on the methylene groups at carbons 10 or 13 . The appropriate starting material is a ketooctadecanoic acid which is prepared from an unsaturated C18 fatty acid precursor or by total synthesis . The (3)H label is introduced by NaB(3)H(4) reduction and the resulting tritiated hydroxy fatty acid then is tosylated, separated into the enantiomers by chiral phase HPLC, and subsequently transformed into stearic acids . A variety of stereospecifically labeled unsaturated fatty acids are obtained using literature methods of microbial transformation with the fungus Saprolegnia parasitica . Two applications are described: (i) In incubations of {10S-(3)H}- and {10R-(3)H}arachidonic acids in human psoriatic scales we show that a 12R-lipoxygenase accounts not only for synthesis of the major product 12R-HETE, but it contributes also, through subsequent isomerization, to the minor amounts of 12S-HETE . (ii) The {10R-(3)H}- and {10S-(3)H}arachidonic acids were also used to demonstrate that prostaglandin ring formation by cyclooxygenases does not involve carbocation formation at C-10 of arachidonic acid as was hypothesized recently . Rev Latinoam Microbiol, 1998 Jan-Jun, 40(1-2), 87 - 107 {Microbial sources of pigments}; Canizares-Villanueva RO et al.; Pigments from natural sources has been obtained since long time ago, and their interest has increased due to the toxicity problems caused by those of synthetic origin . In this way the pigments from microbial sources are a good alternative . Some of more important natural pigments, are the carotenoids, flavonoids (anthocyanins) and some tetrapirroles (chloropyls, phycobilliproteins) . Another group less important are the betalains and quinones . The carotenoids are molecules formed by isoprenoids units and the most important used as colorant are the alpha and beta carotene which are precursors of vitamin A, and some xantophylls as astaxanthin . The pigment more used in the industry is the beta-carotene which is obtained from some microalgae and cyanobacteria . The astaxanthin another important carotenoid is a red pigment of great commercial value, and it is used in the pharmaceutical feed and acuaculture industries . This pigments is mainly obtained from Phaffia rhodozyma and Haematococcus pluvialis and other organisms . The phycobilliproteins obtained from cyanobacteria and some group of algae, have recently been increased on the food industries . In the last years it has been used as fluorescent marker in biochemical assays . Our research group have carried out studies about the factors that improve the production of these pigments obtained from different microbial species as well as the methods for their extraction and application. Mikrobiol Z, 2000 May-Jun, 62(3), 17 - 25 {The molecular-weight characteristics of the bacterial lectins and humus components in soil}; Votselko SK et al.; A method has been developed to determine the molecular-weight distribution of biologically active substances: bacterial lectins and soil humus compounds . The method based on the simultaneous centrifugation of samples and molecular weight standards in the density gradient of NaCl solutions or combined gradient of NaCl and CsCl solutions permits analysing biologically active substances: lectins, proteins, polysaccharides, protein-polysaccharide complexes, humus compounds in the interval of molecular weight of 13.7 kappa {symbol: see text} a to 2000 kappa {symbol: see text} a . The use of this method in the soil researches makes it possible to study the dynamics of change of molecular parameters of the soil organic matter depending on agrotechnical methods as well as to determine transformation regularities of microbial polysaccharides. J Allergy Clin Immunol, 2000 Aug, 106(2), 213 - 27 Chronic sinusitis; Hamilos DL; Sinusitis is a very common chronic illness with a substantial health care impact . This review focuses on factors contributing to sinusitis pathogenesis and chronicity, including anatomic factors, disturbances in mucociliary clearance, microbial pathogens, and inflammatory factors . A distinction is made between "infectious" and "noninfectious" types of inflammation in chronic sinusitis . The inflammatory characteristics of noninfectious inflammation are reviewed primarily in the context of chronic hyperplastic sinusitis with nasal polyposis . Key features of this type of inflammation include the presence of chronic inflammatory cells, large numbers of eosinophils, and IL-5-producing T lymphocytes . Allergic fungal sinusitis is discussed as a special type of chronic sinusitis . Published studies on the outcomes of medical management are reviewed . Finally, algorithms for medical management of chronic sinusitis and allergic fungal sinusitis are presented. Rapid Commun Mass Spectrom, 2000, 14(16), 1507 - 12 Stable carbon and oxygen isotopic analysis of carbon monoxide in natural waters; Tsunogai U et al.; Techniques have been developed to allow on-line simultaneous analysis of concentration and stable isotopic compositions ((13)C and (18)O) of dissolved carbon monoxide (CO) in natural water, using continuous-flow isotope ratio mass spectrometry (CF-IRMS) . The analytical system consisted sequentially of a He-sparging bottle of water, a gas dryer, CO(2)-trapping stage using both Ascarite trap and silica-gel packed gas chromatography (GC), on-line oxidation to CO(2) using the Schutze reagent, cryofocusing, GC purification using a capillary column and measurement by CF-IRMS . Each sample analysis takes about 40 minutes . The detection limit with delta(13)C standard deviation of 0.5 per thousand is 300 pmol and that with delta(18)O deviation of 1.0 per thousand is 750 pmol . Analytical blanks associated with these methods are 21+/-9 pmol . The procedures are evaluated through analyses of temporally varying concentration and isotopic compositions of CO in an artificial lake on the university campus . The delta(13)C and delta(18)O values of CO showed wide variation in accordance with diurnal variation of CO concentration, probably due to significant isotopic effects during photochemical production and microbial oxidation of CO in the aquatic environment . The delta(13)C and delta(18)O values of CO should be a useful tool in studies of the mechanism and pathways of CO production and consumption in natural waters . Eur J Biochem, 2000 Aug, 267(16), 5115 - 22 The plant aspartic proteinase-specific polypeptide insert is not directly related to the activity of oryzasin 1; Asakura T et al.; Many plant aspartic proteinases (APs) are different from animal and microbial APs in that they contain a polypeptide insert, approximately 100 amino acids in length, in the C-terminal region . To interpret the significance of this insert, we constructed an expression system for rice AP oryzasin 1 by linking a pro-oryzasin 1 downstream of glutathione S-transferase (GST) . GST-proOS1 expressed the highest degree of hemoglobin-hydrolytic activity when treated at pH 3.3 and incubated for 24 h at room temperature . We carried out a similar experiment using an insert-lacking proOS1 mutant, GST-DeltaproOS1, as the fusion protein, and found it to show similar activity . This result indicates that the insert is not involved in the production of AP activity . We then investigated the autolysis of the two proteins by Western blot analysis . GST-proOS1 was autolyzed into 67- and 64-kDa fragments, while GST-DeltaproOS1 autolyzed to 54- and 52-kDa products . GST-DeltaproOS1 clearly produced two molecular species early in the autolytic process, and not later than 3 h from the start, but no such clear result was observed in the case of GST-proOS1 . This suggests that, although the presence of the plant AP-specific insert does not influence the enzyme activity by itself, it apparently has an effect on the autolysis of OS1. Clin Exp Immunol, 2000 Aug, 121(2), 302 - 10 Comparative roles of free fatty acids with reactive nitrogen intermediates and reactive oxygen intermediates in expression of the anti-microbial activity of macrophages against Mycobacterium tuberculosis; Akaki T et al.; We assessed the role of free fatty acids (FFA) in the expression of the activity of macrophages against Mycobacterium tuberculosis in relation to the roles of two major anti-microbial effectors, reactive nitrogen intermediates (RNI) and reactive oxygen intermediates (ROI) . Intracellular growth of M . tuberculosis residing inside macrophages was accelerated by treatments of macrophages with either quinacrine (phospholipase A2 (PLA2) inhibitor), arachidonyl trifuloromethylketone (type IV cytosolic PLA2 inhibitor), NG-monomethyl-L-arginine (nitric oxide synthase inhibitor), and superoxide dismutase plus catalase (ROI scavengers) . In addition, M . tuberculosis-infected macrophages produced and/or secreted these effectors sequentially in the order ROI (0-3 h), FFA (0-48 h), and RNI (3 to at least 72 h) . Notably, membranous FFA (arachidonic acid) of macrophages translocated to M . tuberculosis residing in the phagosomes of macrophages in phagocytic ability- and PLA2-dependent fashions during cultivation after M . tuberculosis infection . FFA, RNI and H2O2-mediated halogenation system (H2O2-halogenation system) displayed strong activity against M . tuberculosis in cell-free systems, while ROI alone exerted no such effects . Combinations of 'FFA + RNI' and 'RNI + H2O2-halogenation system' exhibited synergistic and additive effects against M . tuberculosis, respectively, while 'FFA + H2O2-halogenation system' had an antagonistic effect . Moreover, a sequential attack of FFA followed by RNI exerted synergistic activity against M . tuberculosis . Since M . tuberculosis-infected macrophages showed simultaneous production of RNI with FFA secretion for relatively long periods (approx . 45 h) and prolonged RNI production was seen thereafter, RNI in combination with FFA appear to play critical roles in the manifestation of the activity of macrophages against M . tuberculosis. Gastroenterology, 2000 Aug, 119(2), 512 - 20 Nitric oxide in mucosal defense: a little goes a long way; Wallace JL et al.; Nitric oxide (NO) is now recognized as an important modulator of an enormous number of physiological processes, ranging from blood pressure regulation to neuronal transmission to penile erectile function . In the gastrointestinal tract, NO also participates in many physiological and pathophysiological processes . In this review, we summarize the contribution made by NO to the ability of the gastrointestinal mucosa to resist injury induced by luminal toxins and to defend against microbial</