Proc Natl Acad Sci U S A, 1998 Aug 18, 95(17), 10026 - 31 Self-identification of protein-coding regions in microbial genomes; Audic S et al.; A new method for predicting protein-coding regions in microbial genomic DNA sequences is presented . It uses an ab initio iterative Markov modeling procedure to automatically perform the partition of genomic sequences into three subsets shown to correspond to coding, coding on the opposite strand, and noncoding segments . In contrast to current methods, such as GENEMARK {Borodovsky, M . & McIninch, J . D . (1993) Comput . Chem . 17, 123-133}, no training set or prior knowledge of the statistical properties of the studied genome are required . This new method tolerates error rates of 1-2% and can process unassembled sequences . It is thus ideal for the analysis of genome survey and/or fragmented sequence data from uncharacterized microorganisms . The method was validated on 10 complete bacterial genomes (from four major phylogenetic lineages) . The results show that protein-coding regions can be identified with an accuracy of up to 90% with a totally automated and objective procedure. Int J Food Microbiol, 1998 Jun 30, 42(1-2), 79 - 90 A decision support system for the prediction of microbial food safety and food quality; Wijtzes T et al.; The development of a method to predict microbial food safety and quality is described . The manufacture of a food from its ingredients is simulated, using a recipe . Food engineering heuristics are combined with models developed in predictive microbiology . Parameter values of ingredients of foods, such as water activity and pH, and models for microbial growth and decay are used for the prediction of the kinetics of microorganisms generally found in ingredients . The values of these parameters are collected in databases . If required information is lacking, methods are described for making reliable guesses of the parameters . Food quality can be calculated as a function of fluctuating temperature in time . Several food distribution chains can be simulated in order to assess the influence of distribution chains on food quality . The described methods were implemented into a computerised decision support system that can be used in food production, product development and training . In the future it may be possible to apply specific expert knowledge in production and development of foods to improve the quality of prediction. Annu Rev Nutr, 1998, 18, 39 - 61 Carnitine metabolism and its regulation in microorganisms and mammals; Rebouche CJ et al.; In procaryotes, L-carnitine may be used as both a carbon and nitrogen source for aerobic growth, or the carbon chain may be used selectively following cleavage trimethylamine . Under anaerobic conditions and in the absence of preferred substrates, some bacteria use carnitine, via crotonobetaine, as an electron acceptor . Formation of trimethylamine and lambda-butyrobetaine (from reduction of crotonobetaine) from L-carnitine by enteric bacteria has been demonstrated in rats and humans . Carnitine is not degraded by enzymes of eukaryotic origin . In higher organisms, carnitine has specific functions in intermediary metabolism . Concentrations of carnitine and its esters in cells of eukaryotes are rigorously maintained to provide optimal function . Carnitine homeostasis in mammals is preserved by a modest rate of endogenous synthesis, absorption from dietary sources, efficient reabsorption, and mechanisms present in most tissues that establish and maintain substantial concentration gradients between intracellular and extracellular carnitine pools. Poult Sci, 1998 Aug, 77(8), 1126 - 9 Understanding immunology in disease development and control; Qureshi MA et al.; Two functional aspects of the avian immune system, the humoral and the cell-mediated arms, provide the basis for the preventive and protective response against disease-causing microorganisms . On the other hand, certain avian diseases may induce a transient or permanent immunosuppressive state in one or both of these arms, leading to increased disease susceptibility . In addition to the classical immune response, manifested as antibody production or effector cell activation several cytokines and metabolites are also produced . The consequence of cytokine- and metabolite-mediated microenvironments may be either beneficial or result in a noninfectious immunopathology . Nevertheless, the integrity of the immune system and its functional modulation by factors such as genetics, nutrition, and prophylactic approaches continue to be an important focus of attention in current poultry research and production efforts. Poult Sci, 1998 Aug, 77(8), 1119 - 25 Nutritional modulation of resistance to infectious diseases; Klasing KC; Dietary characteristics can modulate a bird's susceptibility to infectious challenges and subtle influences due to the level of nutrients or the types of ingredients may at times be of critical importance . This review considers seven mechanisms for nutritional modulation of resistance to infectious disease in poultry . 1) Nutrition may impact the development of the immune system, both in ovo and in the first weeks posthatch . Micronutrient deficiencies that affect developmental events, such as the seeding of lymphoid organs and clonal expansion of lymphocyte clones, can negatively impact the immune system later in life . 2) A substrate role of nutrients is necessary for the immune response so that responding cells can divide and synthesize effector molecules . The quantitative need for nutrients for supporting a normal immune system, as well as the proliferation of leukocytes and the production of antibodies during an infectious challenge, is very small relative to uses for growth or egg production . It is likely that the systemic acute phase response that accompanies most infectious challenges is a more significant consumer of nutrients than the immune system itself . 3) The low concentration of some nutrients (e.g., iron) in body fluids makes them the limiting substrates for the proliferation of invading pathogens and the supply of these nutrients is further limited during the immune response . 4) Some nutrients (e.g., fatty acids and vitamins A, D, and E) have direct regulatory actions on leukocytes by binding to intracellular receptors or by modifying the release of second messengers . 5) The diet may also have indirect regulatory effects that are mediated by the classical endocrine system . 6) Physical and chemical aspects of the diet can modify the populations of microorganisms in the gastrointestinal tract, the capacity of pathogens to attach to enterocytes, and the integrity of the intestinal epithelium. J Biol Chem, 1998 Aug 21, 273(34), 22014 - 20 A novel carbohydrate-glycosphingolipid interaction between a beta-(1-3)-glucan immunomodulator, PGG-glucan, and lactosylceramide of human leukocytes; Zimmerman JW et al.; The immunomodulator Betafectin(R) PGG-glucan is a homopolymer of glucose derived from yeast cell walls which has been demonstrated to enhance leukocyte anti-infective activity in vitro and in vivo, without the induction of proinflammatory cytokines . We report here the purification of a PGG-glucan-binding element from human leukocytes and its identification as lactosylceramide, a major glycosphingolipid of neutrophils, which includes the CDw17 epitope . The binding of radiolabeled PGG-glucan to purified lactosylceramide was saturable, specific, and time- and temperature-dependent . Lactosylceramides from human leukocytes were fractionated by high performance liquid chromatography in order to analyze the effect of ceramide structure on binding . A variety of fatty acid chain lengths with varying degrees of unsaturation were found to support binding to radiolabeled PGG-glucan . However, DL-lactosylceramides containing dihydrosphingosine did not bind . Radiolabeled PGG-glucan bound several other neutral glycosphingolipids with a terminal galactose, including galactosylceramide, globotriaosylceramide, and gangliotetraosylceramide . The binding of radiolabeled PGG-glucan to lactosylceramide was not inhibited by glycogen, dextran, mannan, pustulan, laminarin, or a low molecular weight beta-(1-3)-glucan, but was inhibited by high molecular weight beta-(1-3)-glucans and by a monoclonal antibody to lactosylceramide . Although this glycosphingolipid has been shown in numerous reports to bind various microorganisms, this represents the first report of lactosylceramide binding to a macromolecular carbohydrate. Arch Immunol Ther Exp (Warsz), 1998, 46(3), 129 - 36 Carcinoembryonic antigen as an adhesion molecule; Krop-Watorek A et al.; Carcinoembryonic antigen (CEA), one of the most widely studied tumor markers, shows homotypic (CEA-CEA) intercellular adhesion and heterotypic adhesion to other members of CEA family, receptors on Kupffer cells, macrophages, microorganisms, and lectins . This review is focused on those adhesive properties of CEA which may pertain to the role of CEA in tumor progression. Ann N Y Acad Sci, 1997 Dec 15, 832, 62 - 8 Development of neutrophil granule diversity; Borregaard N; The neutrophil has intracellular stores of both membrane proteins and soluble proteins that may be incorporated into the plasma membrane and exocytosed, respectively, at different times to meet the demands for assisting the neutrophil in adhesion to endothelium (secretory vesicles), for migration through basement membranes (gelatinase granules), and for phagocytosis, killing, and digestion of microorganisms (specific granules and azurophil granules) . One reason for segregating the proteins into different subpopulations of granules is that some proteins cannot exist in the same compartment (NGAL digested if present in azurophil granules) . Another reason is that the content of the different granules is needed at different times and places . The background for the diversity of neutrophil granules is the timing of biosynthesis, which again most likely is the result of transcriptional control, although this is not yet proven . It is possible that the control of exocytosis is also determined by the same mechanism--a carefully controlled timing of biosynthesis of fusion proteins that ties the content of granules to the likelihood that a given stimulus will result in exocytosis of that individual granule subset. Science, 1998 Aug 14, 281(5379), 976 - 7 Evidence against hydrogen-based microbial ecosystems in basalt aquifers Anderson RT, Chapelle FH, Lovley DR. It has been proposed that hydrogen produced from basalt-ground-water interactions may serve as an energy source that supports the existence of microorganisms in the deep subsurface on Earth and possibly on other planets . However, experiments demonstrated that hydrogen is not produced from basalt at an environmentally relevant, alkaline pH . Small amounts of hydrogen were produced at a lower pH in laboratory incubations, but even this hydrogen production was transitory . Furthermore, geochemical considerations suggest that previously reported rates of hydrogen production cannot be sustained over geologically significant time frames . These findings indicate that hydrogen production from basalt-ground-water interactions may not support microbial metabolism in the subsurface. Acta Orthop Scand, 1998 Jun, 69(3), 311 - 4 High incidence of pathogenic microorganisms in bone allografts explanted in the morgue; Bettin D et al.; We analyzed the influence of the environment on bacterial contamination in 431 bone allografts from 97 donors (68 multiorgan, grafts taken in the operation theater; 29 morgue donors) . From each bone transplant we cultured two aerobic and two anaerobic tissue specimens . The overall contamination rate was 49% (theater 51%, morgue 40%) . In grafts explanted in the morgue, we noted more pathogenic microorganisms (60%) than in multiorgan donors, explanted under aseptic surgical conditions (33%) . We conclude that the harvesting environment constitutes the major source of pathogenic microorganisms. Mikrobiologiia, 1998 May-Jun, 67(3), 305 - 12 {Effect of serotonin (5-hydroxytryptamine) on the growth and differentiation of microorganisms}; Oleskin AV et al.; Serotonin (5-hydroxytryptamine), a neurotransmitter and social behavior factor in higher animals, accelerates culture growth and induces cell aggregation in Escherichia coli and Rhodospirillum rubrum at concentrations of 2 x 10(-7)-2 x 10(-5)M . In the myxobacterium Polyangium sp., 10(-6)-10(-5)M serotonin stimulates cell aggregation and myxospore formation . At concentrations over 20 microM, serotonin induces the opposite effect: it inhibits cell aggregation and microbial culture growth . Serotonin at these concentrations also inhibits the light-dependent membrane potential generation in Rsp . rubrum (the data were obtained by the method of penetrating ions) . Therefore, the above effects can be due to the elimination of the transmembrane electrical gradient by serotonin . As for micromolar serotonin concentrations, their effects presumably result from the specific action of serotonin as an intercellular communication agent accelerating and possibly synchronizing the development of the cell population. Biofizika, 1998 May-Jun, 43(3), 516 - 21 {Dependence of microwave produced heating of cell suspensions on their concentration}; Dergacheva IP et al.; The kinetics of microwave (7 GHz) heating of yeast and bacterial cell suspensions of different concentrations was investigated in the conditions of various thermoisolation of irradiated samples . It was established that independently of type of microorganisms, microwaves produced a more intensive heating of cell suspension in comparison with suspension fluid . The degree of heating was shown to increase with cell concentration . This effect was more expressed under conditions of thermoisolation . At the same irradiation doses and cell concentrations the yeast suspension was heated more vigorously than bacterial one . These differences disappeared when the rise in sample temperature was related to the total cell volume. Am J Ind Med, 1998 Sep, 34(3), 252 - 60 Meta-analyses of brain cancer and farming; Khuder SA et al.; BACKGROUND: A series of meta-analyses of peer-reviewed studies of brain cancer and farming were performed, using 33 studies published between 1981 and 1996 . METHODS: Before the meta-analyses, all studies were reviewed and evaluated for heterogeneity and publication bias . A random-effect model was used to estimate the combined relative risk . RESULTS: A meta-analysis including all the studies yielded an estimator of relative risk equal to 1.30, with a 95% confidence interval (95% CI) of 1.09, 1.56 . The estimator of relative risk obtained from a meta-analysis restricted to female farmers was 1.04 (95% CI = 0.84, 1.29) . A third meta-analysis restricted to studies of farmers residing in the central United States resulted in an estimator of relative risk equal 1.25 (95% CI = 1.09, 1.44) . These findings were not influenced by either a publication bias or a specific study design . CONCLUSION: The consistent significant positive findings suggests that there is a weak association between brain cancer and farming . Exposures commonly experienced by farmers including infectious microorganisms and pesticides may contribute to the increased risk of brain cancer. Am J Respir Crit Care Med, 1998 Aug, 158(2), 412 - 7 Hypersensitivity pneumonitis in peat moss processing plant workers; Cormier Y et al.; A nonsmoking 54-yr-old man, employed in a peat moss packaging plant, developed dyspnea and recurrent fever . The diagnosis of hypersensitivity pneumonitis (HP) was made . Thirteen of 14 coworkers and 13 nonexposed control subjects were studied . Five workers were nonsmokers, two were minimal smokers, and six were smokers . HP was found in another subject . Monocillium sp . and Penicillium citreonigrum, 4.6 x 10(7) CFU/g, were found in the peat moss . Three nonsmokers, the two minimal smokers (including the subject with HP), and the index case had antibodies to these microorganisms; none of the six heavy smokers had antibodies . Serum TNF-alpha was higher in the workers than in the control subjects (0.930 +/- 0.177 versus 0 . 350 +/- 0.076) . Three of the four asymptomatic seropositive workers and two seronegative smokers were further evaluated . All three seropositive workers had normal lung functions and CT but they all had a lymphocytic alveolitis (30, 34, and 68% lymphocytes in their bronchoalveolar lavage {BAL}) . The smokers had normal lung functions, CT, and percentage of BAL lymphocytes (3 and 13%) . This study identified a previously unrecognized work environment that can lead to HP and documented a protective effect of smoking on the response to antigens. Am Ind Hyg Assoc J, 1998 Jul, 59(7), 455 - 60 Control of exposure to airborne viable microorganisms during remediation of moldy buildings; report of three case studies; Rautiala S et al.; Three different techniques for reducing exposure to microorganisms were tested during remediation of moldy buildings . Concentrations of spores (fungi and actinomycetes) were determined by filter sampling before, during, and after remediation . The local exhaust method used for asbestos dismantling was the most effective control method . In the construction zone, concentrations of microorganisms were 4-25 times higher during remediation than before it . In the adjacent area no increase in concentrations was seen . When the construction zone was placed under negative pressure with a fan and isolated with a plastic barrier, concentrations of microorganisms were about 100 times higher there during remediation work . Nevertheless, levels remained low in the adjacent area . The use of a portable exhaust fan with a side-draft hood decreased concentrations of fungi to one-tenth compared with demolition without the control technology . Furthermore, this method prevented the migration of fungal spores from the construction zone to the adjacent area, although it was less effective in prevention of actinomycete spore migration . It also decreased the levels of microorganisms in the construction zone below the preconstruction level within 2 hours . This study showed that levels of airborne microorganisms, including from the working area to adjacent area, can be reduced with commonly used dust control methods during demolition work . However, microorganism levels in the construction zone remained elevated . Therefore, personal protection of construction workers is needed even with control techniques. Biotechnol Prog, 1998 Jul, 14(4), 664 - 6 Method for construction of a simple laboratory-scale nonwoven filament biocatalytic filter Flickinger MC, Mullick A, Ollis DF. A method is described for constructing a simple laboratory-scale nonwoven filament biocatalytic filter (FBF) from multilayer acrylic vinyl acetate copolymer coated thread (yarn) potentially useful for investigation of biotransformations using entrapped enzymes or viable microorganisms . The porous structure of a commercial 128 &mgr;m, 279 denier, 100% polyester thread was sealed with a latex coat (precoat), then coated with a latex + sulfanilamide-azocasein mixture, and finally coated with a latex top coat to generate the multilayer coated thread . The FBF was constructed by drawing the thread across a 4 cm diameter rubber O-ring in the form of multiple layers and sealing the layers with silicone sealer . The FBF is combatible with a commercially available filter housing containing a flow distrtibutor . A method for characterizing the permeability of the sealant (top) coat of the FBF using azocasein release was also developed. Klin Lab Diagn, 1998 Jun, (6), 22 - 3 {Cytological changes in the cervix uteri and bacterial vaginosis}; Novikova EG et al.; Bacterial vaginosis (BV) is a highly prevalent infectious disease causing numerous complications in obstetrics, gynecology, and in the newborns . The necessity of investigating BV is explained by its increasing incidence, including its asymptomatic forms, its probable sexual transmission, and its possible role in the etiology and pathogenesis of diseases of the cervix uteri because of exposure of the squamous epithelium of the cervix uteri, permanently regenerating and therefore highly sensitive to unfavorable effects, to high concentrations of opportunistic microorganisms . Our findings indicate that women with BV, particularly those with signs of another infection, are at risk of diseases of the cervix uteri . The risk group can be detected by simple and available methods for detecting BV with obligatory cytological studies, particularly in cases with inflammatory processes, and additional tests for associated infections (chlamydiosis, herpes simplex, etc.), whose role in the pathogenesis of cervical diseases is well known. Kansenshogaku Zasshi, 1998 Jun, 72(6), 585 - 92 {Clinical analysis of patients with severe pneumonia requiring mechanical ventilation}; Kobashi Y et al.; To clarify the clinical features and select the appropriate antibiotic therapy for patients with severe pneumonia requiring mechanical ventilation, we performed a clinical analysis of 65 patients with this condition . The following results were obtained . The majority of the patients were elderly males, whose performance status was poor (PS 2.2) and who had an underying disease . Abnormal physical signs included tachypnea, tachycardia and consciousness disturbance . Abnormal laboratory findings included hypoalbuminemia, and liver and renal dysfunction . The causative microorganisms were isolated from half of these patients . A number of antibiotics were administered and steroid pulse therapy was also performed for half of these patients . Nevertheless the prognosis was poor because the percentage of deaths was high (50.8%). Pathobiology, 1998, 66(3-4), 141 - 4 M cells as portals of entry for HIV; Owen RL; Accumulating evidence points toward active uptake by mucosal antigen sampling cells as the mechanism for rectal HIV acquisition . Organized lymphoid tissue in the intestine consists of lymphoid follicles with an epithelium containing M cells specialized for uptake and transport of microorganisms, bringing them into contact with lymphoid cells . M cells have been found in the human colon and rectum, and adherence and uptake of HIV by M cells in mouse and rabbit Peyer's patches has been demonstrated in vitro . In an in vivo mouse model of viral acquisition, reovirus is actively taken up by M cells into rectal lymphoid tissue containing CD4 lymphocytes and macrophages, which are targets and replication sites for HIV . Immunization strategies for prevention of HIV transmission should include a mucosal component to prevent initial entry, since elimination from cellular sanctuaries remains an elusive goal. Parasitol Res, 1998 Jul, 84(7), 559 - 64 Detection of parasites with DNA-binding bisbenzimide H33258 in Pneumocystis carinii- and Leishmania-containing materials; Laube U et al.; Even for routine purposes, standard staining of Pneumocystis- or Leishmania-containing materials, e.g., with Giemsa or Diff-Quik, is often unsatisfactory due to poor contrast and to staining of irrelevant structures . In comparison, the bisbenzimide dye Hoechst 33258, a DNA-binding fluorochrome, allows a more precise analysis of such materials . Bisbenzimide stained all stages of these fungal or protozoal organisms with brilliant contrast against a uniformly dark background . The level of background luminescence and staining of detritus or non-DNA structures was very low . Organisms were stained both outside of and within phagocytic cells with equal intensity . Counting of individual microorganisms, e.g., in macrophages heavily parasitized with Leishmania or in Pneumocystis-infected bronchoalveolar lavage, was simplified and more precise . Air-dried cell suspensions, cytocentrifuge preparations, impression smears, or cryocut micrographs showed the advantages of bisbenzimide staining over Diff-Quik . Staining with bisbenzimide could be a valuable auxiliary technique for the analysis of material infected with a variety of microorganisms. Hum Gene Ther, 1998 Jul 20, 9(11), 1561 - 70 Correction of respiratory burst activity in X-linked chronic granulomatous cells to therapeutically relevant levels after gene transfer into bone marrow CD34+ cells; Becker S et al.; Chronic granulomatous disease (CGD) is a disorder of the lymphohematopoietic system, whereby phagocytes of affected patients are unable to kill microorganisms . CGD is caused by a functional defect in the phagocytic nicotinamide adenine dinucleotide phosphatase (NADPH) oxidase (phox) enzyme complex, leading to a lack of microbicidal metabolites . As a therapeutic approach toward the predominant X-linked form of CGD, we have developed a bicistronic retroviral vector containing the coding sequences of gp91-phox and a cytoplasmically truncated version of the human low-affinity receptor for nerve growth factor (deltaLNGFR) . Full reconstitution of superoxide-generating activity was achieved with this vector in a gp91-phox-deficient cell line . Using an optimized gene transfer protocol, up to 85% of the CD34+ cells obtained from the bone marrow of X-CGD patients were transduced . CD15+ cells differentiated in vitro from transduced X-CGD CD34+ cells showed correction of NADPH oxidase activity to 45-52% of normal levels whereas deltaLNGFR expression was found in 40-67% of the CD15+ cells . Moreover, immunoblots prepared from extracts of transduced CD15+ cells revealed gp91-phox protein levels similar to those found in neutrophils derived from normal CD34+ cells . Taking into consideration that superoxide production in only 5 to 10% of wild-type neutrophils is sufficient to protect X-CGD heterozygotes from serious infections, the results achieved in this study shows that for X-CGD patients a curative approach based on the genetic modification of hematopoietic stem/progenitor cells is feasible. Biol Neonate, 1998, 74(2), 163 - 76 Protective function of proteins and lipids in human milk; Hamosh M; Human milk provides the infant with protection against infectious diseases . This protection is conferred through several mechanisms: specific antibody targeted protection against pathogens in the infant's environment (through milk IgA, IgG, and IgM) and broad-spectrum, nonspecific protection provided through several distinct mechanisms . These are: bactericidal effects (lactoferrin), bacteriostatic action (lactoferrin, lysozyme), lysis of microorganisms (lysozyme), antiviral effects (lactoferrin, products of milk fat digestion), antiprotozoan activity (free fatty acids produced during gastric and intestinal digestion of milk fat), and ligand action (inhibition of Helicobacter pylori adhesion to gastric mucosa by kappa-casein) . In addition to these protective functions of the proteins and lipids of human milk, several enzymes present in human milk might provide protection by generating components that are bactericidal (bile salt dependent lipase, peroxidase), prevent inflammatory reactions (platelet-activating factor acetylhydrolase), or protect the integrity of milk proteins (antiproteases). Biol Neonate, 1998, 74(2), 143 - 62 Glycoproteins of the human milk fat globule in the protection of the breast-fed infant against infections; Peterson JA et al.; Nonimmunological components in human milk can protect breast-fed infants against infection by microorganisms . The structural and functional characteristics of four such components are discussed . The mucin inhibits binding of S-fimbriated Escherichia coli to bucal epithelial cells; lactadherin prevents symptomatic rotavirus-induced infection; glycoaminoglycans inhibit binding of human immunodeficiency virus gp120 to its host cell CD4 receptor, and oligosaccharides provide protection against several pathogens and their toxins. Curr Opin Biotechnol, 1998 Jun, 9(3), 247 - 51 Terrestrial biotechnology Lynch JM. Ecophysiological and molecular biological investigations of soil microorganisms have developed well, including critical studies of the fate and transport of genetically-modified microorganisms . Such studies will make contributions to areas ranging from the understanding of global change to the catabolism of xenobiotics in soil . Inundative inoculation procedures have not yet sustained their early promise . Greater opportunity appears to lie in the management of indigenous or intrinsic biota . For the protection of human health and the environment, environmental diagnostics, which will include the use of novel biosensors, would seem to offer great prospects. Vet Q, 1998, 20 Suppl 3, S83 - 7 Passive and active protection against disorders of the gut; Mestecky J et al.; The large surface area of mucosal surfaces, particularly of the gastrointestinal tract, is protected against microorganisms and environmental antigens by various innate factors (e.g., mucins, lactoferrin, and others) and specific antibodies which are of IgA, or in some species, IgG Isotypes . Passive protection provided by effective prenatal transplacental transport of maternal antibodies and/or post-natal consumption of milk antibodies in breastfed newborns, is essential for the survival of neonates . Passive protection of mucosal surfaces by pre-formed antibodies in non-breast juveniles or adults is currently used only on an experimental basis: IgA-enriched preparations of gamma-globulin have been successfully given to children, and antibodies specific for several gastrointestinal pathogens have been isolated from immunized cows' milk, hens' eggs, or transgenic plants . Systemic administration of pre-formed antibodies is effective for protection against intestinal pathogens in species (e.g., mice, rats) endowed with efficient hepatobiliary transport of IgA into the gut lumen . However, this route of antibody administration is of limited efficiency in other species, including humans, in which almost all intestinal antibodies are produced locally by plasma cells in the gut mucosa and are not derived to a significant degree from the circulation . Active immunization is preferable for long-lasting protection . The site of immunization and presence of lymphoid tissues with inductive potential play an essential role in generating humoral immune responses in mucosal secretions . The relative efficiency of immunization routes (e.g., oral, nasal, rectal or genital) in the induction of preferential antibody responses in the intestinal secretion has not been studied extensively . Furthermore, suitable antigen delivery systems for achieving this goal must also be considered. Eur J Pharm Biopharm, 1998 Jan, 45(1), 3 - 8 Pharmaceutical and therapeutic applications of artificial cells including microencapsulation; Chang TM; Artificial cells for pharmaceutical and therapeutic applications started as microencapsulation on the micron scale . This has now expanded up to the higher range of macrocapsules and down to the nanometer range of nanocapsules and even to the macromolecular range of cross-linked hemoglobin as blood substitutes . This author first reported microencapsulation of biologically active material in 1957 (T.M.S . Chang, Hemoglobin corpuscles . Research Report for Honours Physiology, Medical Library, McGill University, 1957 . (Also reprinted as part of 30th anniversary in Artificial Red Blood Cells Research, J . Biomater . Artif . Cells Artif . Organs 16 (1988) 1-9.) and 1964 (T.M.S . Chang, Semipermeable microcapsules, Science 146 (1964) 524-525) . While pharmaceutical research has made use of these approaches for drug delivery, this author has been concentrating on the encapsulation of biotechnological products for therapeutic applications . Therefore, there was little interaction between the two approaches . In the last 10 years, pharmaceutical research, as in other areas of research, has become increasingly interested in biotechnology . Because of this interest, this article is a brief overview of developments of artificial cells for biotechnological products with emphasis on hemoglobin, enzymes, cells and genetically engineered microorganisms. Microb Ecol, 1998 Sep, 36(2), 212 - 9 Aerial Transport of Keratinaceous Substrate and Distribution of the Fungus Geomyces pannorum in Antarctic Soils Marshall WA. > Abstract Aerobiological sampling was conducted year-round at three sites on Signy Island, maritime Antarctic, between December 1992 and January 1994, and during the summer at a fourth coastal site . The concentrations of keratinaceous particles were monitored . Feather fragments were the most abundant of all particle types trapped . Seal hairs were also common, particularly on the coast . Numbers of both particle types were most common in the air in summer . The Antarctic soil fungus Geomyces pannorum, which is able to utilize keratin-based substrates, was also present in aerobiological samples on Signy Island . G . pannorum was only found during early winter on the year-round sampling sites . It was more abundant during summer in the air at the coastal site, which was more heavily influenced by seals, birds and humans . Skuas were swabbed when they returned to the island early in summer . G . pannorum was recovered in culture, suggesting that these birds may act as vectors for the transport of microorganisms between Antarctica and more northern landmasses . Organic material deposited on snow was concentrated on the soil at the edge of the ice cap by melt wash, making additional keratin and other organic substrates available to soil microorganisms. Appl Environ Microbiol, 1998 Aug, 64(8), 3114 - 7 Transformation of the ionic X-ray contrast agent diatrizoate and related triiodinated benzoates by Trametes versicolor; Rode U et al.; Iodinated X-ray contrast agents are considered to be nondegradable by microorganisms . The decomposition of the ionic X-ray contrast agents Diatrizoate (3,5-di(acetamido)-2,4,6-triiodobenzoic acid) and Iodipamide (3,3'-adipoyl-diimino-di(2,4,6-triiodobenzoic acid) and related triiodinated benzoates (Acetrizoate {3-acetylamino-2,4, 6-triiodobenzoic acid} and Aminotrizoate {3-amino-2,4, 6-triiodobenzoic acid}) by Trametes versicolor has been investigated . The fungus was able to transform all tested triiodinated benzoates cometabolically . During transformation of these compounds, iodide was released, but deiodination was not complete . T . versicolor liberated traces of 14CO2 from uniformly ring-14C-labeled Diatrizoate (3,5-di(acetamido)-2,4,6-triiodobenzoate) . Various extracellular metabolites were detected during transformation of the different substances . In the transformation of Diatrizoate, the three main metabolites were identified as 3,5-di(acetamido)-2, 6-diiodobenzoic acid, 3,5-di(acetamido)-2,4-diiodobenzoic acid, and 3,5-di(acetamido)-2-iodobenzoic acid, suggesting reductive deiodinations in steps as initial transformation steps. Pediatr Infect Dis J, 1998 Jul, 17(7), 645 - 9 A serologic study of organisms possibly associated with pertussis-like coughing; Wirsing von Konig CH et al.; OBJECTIVE: To assess the frequency of serologic evidence for an infection with microorganisms other than Bordetella pertussis in children with pertussis-like coughs . METHODS: The study was performed within a protective efficacy trial of an acellular pertussis vaccine . Children who coughed for >7 days and had no laboratory evidence of recent infection with B . pertussis were eligible for the present study . Antibodies to Mycoplasma, Chlamydia, respiratory syncytial virus and influenza viruses A and B were measured by complement fixation, and antibodies to adenovirus and parainfluenza viruses 1, 2 and 3 were measured by enzyme-linked immunosorbent assay (ELISA) in acute and convalescent serum samples . Significant titer rises (4-fold titer rise in complement fixation, 100% increase of units in ELISA) and concentrations of antibodies beyond age-specific reference values were regarded as indicative of recent infection . In some children IgM antibodies to Epstein-Barr virus and to cytomegalovirus were also measured by ELISA . RESULTS: A total of 149 of 1179 (12.6%) children had no laboratory evidence of B . pertussis infection . Serologic evidence for other infections were found in 56% (83 of 149) . Adenovirus (33), parainfluenza viruses 1, 2 and 3 (18), Mycoplasma pneumoniae (15) and respiratory syncytial virus (14) were most common . Of this group 48% had been vaccinated against pertussis . CONCLUSION: We present data that a proportion of pertussis-like coughs in children may be caused by adenovirus, parainfluenza viruses, respiratory syncytial virus and Mycoplasma . The differential diagnosis of pertussis-like coughs by laboratory methods should include these infections, especially in vaccinated children. Zentralbl Hyg Umweltmed, 1998 Jun, 201(2), 125 - 33 Investigations on the survival time of outdoor microorganisms on air filters; Moritz M et al.; Outdoor microorganism survival on air filters was examined in 16-day field investigations . Using a mobile filter testing device, samples of fiberglass pocket filters (filter class F7) were ventilated with outdoor air, and their microorganism contents were determined at 1, 2, 4, 8 and 16-day intervals . The results showed a mean survival time of microorganisms deposited on the air filters of 1 to 3 days. Braz J Med Biol Res, 1998 Jan, 31(1), 105 - 10 Parasitic infections in germfree animals; Vieira LQ et al.; The association of vertebrate hosts with the indigenous microbiota and its effect on the response to infections has long been a subject of scientific curiosity . From the first theory supported by Louis Pasteur that life would be impossible in the absence of associated microorganisms to the development of germfree mammals for research, a lot was learned about how the normal microbiota influences the environment in which pathogens may find themselves . In the present review, we attempt to summarize the more recent results from our group and others on the influence of the normal microbiota on the outcome of parasitic infections . Our results and those of others point to a complex relationship between the mammalian system and its indigenous microbiota, leading to greater resistance to some infections and enhanced susceptibility to others. Vet Q, 1998 Jul, 20(3), 81 - 8 Maintenance of Brucella abortus-free herds: a review with emphasis on the epidemiology and the problems in diagnosing brucellosis in areas of low prevalence; Bercovich Z; This review covers some epidemiological aspects that allow Brucella to survive, spread, and maintain itself in the environment . Because the success of maintaining Brucella-free herds is determined by the efficiency of the serological tests to detect a single infected animal the limitations of the traditional serological tests are emphasized . Serological tests cannot differentiate between cattle infected with Brucella and cattle infected with microorganisms that serologically cross-react with B . abortus antigen . These cattle and cattle with 'natural' antibodies jeopardize the Brucella-free status of a herd . Likewise, infected cattle with serologically inconclusive test results or which elude detection are also a hazard to Brucella-free herds . Since cattle that elude detection with serological tests and the presence of non-specific serum antibodies in healthy cattle have long been recognized as problems, it is opportune to reconsider the procedures currently used to diagnose brucellosis in individual animals . Use of the skin delayed-type hypersensitivity test in addition to serological tests will significantly improve the diagnosis of brucellosis . This will limit the financial loss incurred by outbreaks of brucellosis. Clin Podiatr Med Surg, 1998 Jul, 15(3), 499 - 512, vi Review and consideration of coagulopathies; Levin M et al.; Blood components bring nutrients to the tissues, remove wastes, provide defenses against microorganisms and foreign bodies, and retain sufficient fluidity to keep the system functioning properly . Coagulation factors are also present in the blood as part of a sensitive system that stems the flow of blood from a wound and maintains homeostasis . These factors include anuclear platelets that originate from megakaryocytes in the bone marrow, as well as soluble factors in precursor form, and calcium ion . Faults in single or multiple parts of this system, which can be determined in the patient's history, may result in bleeding problems that may be clinically relevant . Clarification of coagulation defects requires cooperation with a hematologist before medication that affects the coagulation system is prescribed or before any procedures that may result in bleeding are undertaken. Vaccine, 1998 Jul, 16(11-12), 1111 - 5 HIV-1 envelope protein gp120 triggers a Th2 response in mice that shifts to Th1 in the presence of human growth hormone; Mellado M et al.; Immunization of mice with HIV-1-gp120 results in predominant activation of the Th2 lymphocyte subset, leading to enhanced IL-4 production . Administration of human growth hormone at the time of gp120 immunization provokes a change in the cytokine production pattern, with lower IL-4 and higher gamma-IFN and IL-2 synthesis levels, indicating a preferential switch in stimulation from Th2 to Th1 cells . A growth hormone would thus be of great use for pharmacological intervention in those cases in which an infectious microorganism evades immune defenses by provoking a Th2 response . In addition, the ability of growth hormone to induce a Th1-type response upon vaccination with an HIV-antigen should be examined in the development of new therapeutic strategies or in the design of novel vaccines against HIV infection. Extremophiles, 1997 Aug, 1(3), 111 - 6 The molecular biology of barophilic bacteria; Kato C et al.; Many microorganisms from the deep-sea display high-pressure-adapted--also described as barophilic or piezophilic--growth characteristics . Phylogenetic studies have revealed that a large proportion of the barophilic bacteria currently in culture collections belong to a distinct subgroup of the genus Shewanella, referred to as the "barophile branch." Many of the basic properties of barophiles that enable their survival at extremes of pressure remain to be elucidated . However, several genes whose expression is regulated by pressure, or which appear to be critical to baroadaptation, have been uncovered . One such operon, whose presence appears to be restricted to the "barophile branch," has been identified in DNA samples obtained from sediments recovered in the deepest ocean trench . In the case of another set of pressure-regulated genes, regulatory elements required for pressure signaling have been uncovered . The nature and regulation of these genes is discussed. Environ Health Perspect, 1994 Jun, 102(6-7), 552 - 4 Screening and Separation of Microorganisms Degrading PCBs; Bokvajova A et al.; We performed an assay to assess the polychlorinated biphenyl (PCB) degradative capability and congener specificity of aerobic microorganisms . Microbial strains were isolated and separated from different types of soils in the Czech Republic, and their PCB-degrading abilities were compared . An industrial mixture of PCB congeners ranging from dichloro- to hexachlorobiphenyl and representing various chlorination patterns was used throughout . The PCB degradative ability of microorganisms was determined by gas chromatography after 7 days of incubation . The degree of degradation was found to depend on the number of chlorine substituents. Aliment Pharmacol Ther, 1998 Jun, 12(6), 563 - 8 Treatment of Helicobacter pylori infection in infants in rural Bangladesh with oral immunoglobulins from hyperimmune bovine colostrum; Casswall TH et al.; BACKGROUND: Antibodies from hyperimmune bovine colostrum have been shown to be effective in treatment against a variety of microorganisms, including Helicobacter pylori in adults . AIM: To test this form of treatment in a small group of H . pylori infected children in a periurban community in Bangladesh . METHODS: Twenty-four infants, 4-29 months old (mean age 16.5+/-7.7 months) and infected with H . pylori, were treated with purified immunoglobulins from hyperimmune bovine colostrum for 1 month, in a placebo-controlled, double-blind pilot study . Diagnosis was established with 13C-urea breath test (UBT) before and after the treatment period and at a 1-month follow-up . RESULTS: None of the hyperimmune bovine colostrum-treated children became UBT negative . Five children initially positive in the UBT screening spontaneously became negative by the start of the study with hyperimmune bovine colostrum/placebo . At the end of the 1-month study period, three had became positive again . CONCLUSION: Hyperimmune bovine colostrum does not eradicate H . pylori infection in infants . Transient H . pylori infection is common among infants in high endemic areas, as is reinfection after clearance . This presents obstacles to evaluation of therapeutic investigations in young children in areas where H . pylori is prevalent. J Food Prot, 1998 Jul, 61(7), 812 - 6 Immunomagnetic separation and flow cytometry for rapid detection of Escherichia coli O157:H7; Seo KH et al.; A rapid method for detecting Escherichia coli O157:H7 combining immunomagnetic beads (IMB) and flow cytometry was developed . Labeling antigens separated by IMB with fluorescent antibody enabled the detection of < 10(3) CFU bacteria per ml in pure culture . The optimum concentration of magnetic beads for flow cytometry was lower (ca . 10(5) particles per ml) than that reported for conventional IMB assay (more than 6 x 10(6) to 8 x 10(6) particles per ml) . Immunomagnetic separation and flow cytometry (IMFC) were evaluated for detecting E . coli O157:H7 in the presence of a competing microorganism and for detecting antibodies in potassium phosphate buffer . The total assay time from separating antigens with IMB to analyzing with flow cytometry was about 1 h . IMFC detected 10(3) to 10(4) CFU of E . coli O157:H7 per ml in ground beef enrichment broth and could effectively discriminate between E . coli O157:H7 and competing natural flora . The new assay system provides another approach to separation and detection of low populations of pathogens and shows potential for detecting low concentrations of toxins and other soluble antigens directly from food in a short time. J Nat Prod, 1998 Jul, 61(7), 922 - 6 Microbial transformations of isocupressic acid; Lin SJ et al.; Microbial transformations of the labdane-diterpene isocupressic acid (1) with different microorganisms yielded several oxygenated metabolites that were isolated and characterized by MS and NMR spectroscopic analyses . Nocardia aurantia (ATCC 12674) catalyzed the cleavage of the 13,14-double bond to yield a new nor-labdane metabolite, 2 . Cunninghamella elegans (-) (NRRL 1393) gave 7beta-hydroxyisocupressic acid (3) and labda-7,13(E)-diene-6beta,15, 17-triol-19-oic acid (4), and Mucor mucedo (ATCC 20094) gave 2alpha-hydroxyisocupressic acid (5) and labda-8(17),14-diene-2alpha, 13-diol-19-oic acid (6). Mutat Res, 1998 Jun 18, 402(1-2), 139 - 50 Effects of antimutagens on development of drug/antibiotic resistance in microorganisms; Pillai SP et al.; The effects of polyamines and related compounds on the development of drug/antibiotic resistance in a variety of bacterial strains were studied . Methods employed included standard toxicity assays, modified Ames tests for mutation frequencies and antimutagenic effects, prophage induction assays, and recA-lacZ and ada-lacZ induction assays . Using these methods, we have shown that the polyamines produce strong antimutagenic effects against EMS and MMS-induced antibiotic resistance . Spermidine also seems to have antimutagenic potential against 4NQO-induced mutations . DNA fidelity assays suggest that polyamines play a vital role in DNA synthesis, and several polyamines prevent the development of resistance to dihydrostreptomycin . The polyamine putrescine appears to be required for streptomycin action and also enhances the activity of some antibiotics (e.g., neomycin, kanamycin) but shows no enhancing effect on tetracycline or erythromycin . The potential significance of these studies for infectious diseases and tumor therapy is discussed . Berl Munch Tierarztl Wochenschr, 1998 Jun, 111(6), 211 - 3 Case report: necrotic glossitis and sinusitis in a cow caused apparently by a Fusobacterium necrophorum like microorganism; Yeruham I et al.; An unusual case of necrotic infection of the tongue and unilateral necrotic maxillar sinusitis, in a cow is reported . The prominent clinical findings were: a marked salivation, unilateral mucopurulent nasal discharge, diffuse necrotic lesions on the ventral side of the tongue and fetid breath . Clinico-pathological and pathological findings and abnormalities in the haemogram were probably caused by the toxins produced by the causative organism--Fusobacterium necrophorum like microorganism. Rev Inst Med Trop Sao Paulo, 1997 Nov-Dec, 39(6), 345 - 52 New strategies on molecular biology applied to microbial systematics; Hofling JF et al.; Systematics is the study of diversity of the organisms and their relationships comprising classification, nomenclature and identification . The term classification or taxonomy means the arrangement of the organisms in groups (rate) and the nomenclature is the attribution of correct international scientific names to organisms and identification is the inclusion of unknown strains in groups derived from classification . Therefore, classification for a stable nomenclature and a perfect identification are required previously . The beginning of the new bacterial systematics era can be remembered by the introduction and application of new taxonomic concepts and techniques, from the 50's and 60's . Important progress were achieved using numerical taxonomy and molecular taxonomy . Molecular taxonomy, brought into effect after the emergence of the Molecular Biology resources, provided knowledge that comprises systematics of bacteria, in which occurs great evolutionary interest, or where is observed the necessity of eliminating any environmental interference . When you study the composition and disposition of nucleotides in certain portions of the genetic material, you study searching their genome, much less susceptible to environmental alterations than proteins, codified based on it . In the molecular taxonomy, you can research both DNA and RNA, and the main techniques that have been used in the systematics comprise the build of restriction maps, DNA-DNA hybridization, DNA-RNA hybridization, sequencing of DNA sequencing of sub-units 16S and 23S of rRNA, RAPD, RFLP, PFGE etc . Techniques such as base sequencing, though they are extremely sensible and greatly precise, are relatively onerous and impracticable to the great majority of the bacterial taxonomy laboratories . Several specialized techniques have been applied to taxonomic studies of microorganisms . In the last years, these have included preliminary electrophoretic analysis of soluble proteins and isoenzymes, and subsequently determination of deoxyribonucleic acid base composition and assessment of base sequence homology by means of DNA-RNA hybrid experiments beside others . These various techniques, as expected, have generally indicated a lack of taxonomic information in microbial systematics . There are numberless techniques and methodologies that make bacteria identification and classification study possible, part of them described here, allowing establish different degrees of subspecific and interspecific similarity through phenetic-genetic polymorphism analysis . However, was pointed out the necessity of using more than one technique for better establish similarity degrees within microorganisms . Obtaining data resulting from application of a sole technique isolatedly may not provide significant information from Bacterial Systematics viewpoint. Medicina (B Aires), 1997, 57(5), 608 - 16 {Superantigens: a particular interaction between microorganisms and the immune system}; Antunez MI et al.; The discovery of the superantigens (SAgs) offered new insights on the interaction between microorganisms and the host immune system . Associated to Major Histocompatibility Complex (MHC) class II molecules, SAgs bind to the variable domain of the beta chain (V beta) of the TCR alpha beta engaged in the family specificity of lymphocytes . Therefore, these molecules are able to activate a high number of T lymphocytes as well as surface MHC class II bearing cells, leading to an overriding release of cytokines and inflammatory mediators, which have been related to their toxic effects . Endogenous SAgs are encoded by murine tumor proviruses (Mtv) which are integrated in the genome of mice . Bacteria and viruses produce exogenous SAgs and those related to food poisoning have been widely studied . The presence of parasite SAgs is still unclear and further studies are required to establish their existence and effects on the corresponding infections. J Environ Sci Health B, 1998 Jul, 33(4), 369 - 79 Microbial degradation of carbosulfan by carbosulfan--and carbofuran-retreated rice soil suspension; Sahoo A et al.; The role of microorganisms in the degradation of carbosulfan (2,3-dihydro-2,2-dimethyl-7-benzofuranyl-(di-n-butyl)-aminosulfenyl++ + methyl carbamate), an analogue of carbofuran (2,3-dihydro-2,2-dimethyl-7-benzofuranyl-N-methyl carbamate) was studied by selective enrichment of microorganisms degrading either or both insecticides by repeated application of the insecticides, individually or in combination to flooded soil . Soil suspension from the pots treated with carbosulfan and carbofuran, individually or in combination collected after two applications, effected distinctly more rapid hydrolysis of carbosulfan than did the suspension from untreated pots or the uninoculated medium . The rate of hydrolysis was further accelerated by soil suspensions collected after six applications of the insecticides in the order carbosulfan treated > carbofuran treated > carbosulfan + carbofuran treated . The ability of treated and untreated suspension to degrade carbofuran was also studied . The rate of degradation of carbofuran by the suspension was in the order carbofuran retreated > carbosulfan + carbofuran retreated > carbosulfan retreated soil . Further involvement of microorganism in the rapid degradation of carbosulfan was confirmed by testing the degradation in sterilized and nonsterilized enrichment culture. Arch Latinoam Nutr, 1997 Dec, 47(4), 377 - 81 {Evaluation of the nixtamal-tortilla-making quality of mixtures of corn (Zea mays) and hard beans (Phaseolus vulgaris)}; Garcia-Osorio C et al.; In Mexico, some varieties of beans become hard during storage, and required a longer time for cooking . Beans which need more than four hours to cook are deemed unsuitable for human consumption by the government agency CONASUPO even though their nutritional value is unaltered . The objective of this study was to evaluate the nixtamal-tortilla-making quality of mixtures of maize and hard beans, protein, sensory evaluation, and shelf life of the tortillas . The tortillas were made from mixtures of maize with 5% and 10% hard beans without the seed coat and compared with tortillas made with 100% maize . The mixtures and the control were nixtamalized for 20, 30 and 40 minutes with 1% lime (CaO) . The maximum viscosity of the mass were statistically equal to that of the control . The mixture with 10% beans, 90% maize, and 30 min of nixtamalization produced tortillas with 26.3% more protein than the control . The texture evaluated in the Instron showed that the tortillas with 10% beans were harder than the control; however, in the sensory evaluation, the recently-made tortillas with 30 min nixtamalization were judged the best, with no significant differences between the control and the mixtures of maize with hard beans . The analysis of fungi, yeasts, and bacteria at room temperature and with refrigeration (4 degrees C), showed that the growth of microorganisms was directly proportional to the percentage of beans added and the duration of storage . The largest number of microorganisms was found at room temperature after 48 h of storage. Arch Latinoam Nutr, 1997 Dec, 47(4), 372 - 6 {Shelf-life and sensorial evaluation of corn tortillas, made with preservatives and texture conditioners}; Ordaz Ortiz JJ et al.; With the objective of producing packaged tortillas with a longer shelf-life which, at the same time, have the qualities of fresh tortillas, the effects of preservatives and texture conditioners on rheologic and sensory characteristics and shelf-life of tortillas made with nixtamalized corn flour were studied . The preservatives evaluated were potassium sorbate (SK) and calcium propionate (PCa) . The texture conditioners used were carboxymethylcellulose (CMC) and sodium stearyl-2 lactilate (SS2L) . Fresh tortillas were evaluated for pH, yield, texture, elasticity, and sensory quality . The packaged tortillas were packed in polyethylene bags and stored at 4 degrees C . The tortillas with 0.1% SK, 0.1% PCa, and 0.25% SS2L were the most acid (pH = 5.12), had the longest shelf-life (53 days with no microorganism growth), and the lowest total count of aerobic mesophylls (23 colony forming units) . The highest yields resulted from the treatment with 0.5% CMC, producing the most elastic tortillas but those with the shortest shelf-life (18 and 24 days) . The sensory evaluation, done ten days after packing by five trained panel members, judged that best treatment was that which contained 0.1% SK, 0.1% PCa, and 0.5% CMC . These tortillas were judged to be the softest and most elastic . For the remaining attributes, the best tortillas were those processed by the traditional method (fresh) . In the pleasure test, the opinion of the consumers was that the tortilla with the best flavor was the traditionally prepared tortilla . Nevertheless, the treatments with mixtures of preservatives and texture conditioners were graded with scores similar to those obtained by two commercial packaged tortillas. Infect Immun, 1998 Aug, 66(8), 3510 - 8 Inducible nitric oxide synthase-deficient mice develop enhanced type 1 cytokine-associated cellular and humoral immune responses after vaccination with attenuated Schistosoma mansoni cercariae but display partially reduced resistance; James SL et al.; High levels of nitric oxide (NO) are produced by inducible nitric oxide synthase (iNOS) in response to activating signals from Th1-associated cytokines and play an important role in cytotoxicity and cytostasis against many pathogenic microorganisms . In addition to its direct effector function, NO serves as a potent immunoregulatory factor . NO produced by gamma interferon-activated macrophages immobilizes and kills Schistosoma mansoni larvae, and several studies have indicated a role for this pathway in protective immunity against this parasite . The potential regulatory influence of NO in immunity to S . mansoni is less well understood . In this study, we have used iNOS-deficient mice to determine the role of NO in mice vaccinated with irradiated cercariae of S . mansoni . We show by enzyme-linked immunosorbent assay and reverse transcriptase PCR analysis that vaccinated iNOS-deficient mice develop exacerbated type 1 cytokine responses in the lungs, the site where resistance to infection is primarily manifested . In addition, parasite-specific immunoglobulin G2a (IgG2a) and IgG2b antibody responses were significantly increased in vaccinated iNOS-deficient animals and total IgE antibody levels in serum were decreased relative to those in wild-type controls . Surprisingly, since resistance in this vaccine model is largely Th1 dependent and since Th1-related cellular and humoral immune responses were found to be exacerbated in vaccinated iNOS-deficient mice, vaccine-elicited protective immunity against challenge infection was found to be reduced . These findings demonstrate that iNOS plays a paradoxical role in immunity to S . mansoni, both in the effector mechanism of resistance and in the down regulation of the type 1 cytokine response, which is ultimately required for NO production. Rays, 1998 Jan-Mar, 23(1), 32 - 41 Microbiology and diagnosis of tuberculosis; Fadda G et al.; Major features of Mycobacterium tuberculosis as the slow metabolism and the large amount of lipid in the outer layer of the cell wall, shown by acid-fast staining, are responsible for its peculiar morphology and pathogenicity . For correct diagnosis of M . tuberculosis infection, direct microscopy of the pathological sample, isolation and identification on suitable culture media of the microorganism and in vitro tests of antituberculous drug sensitivity are required . Alternative time-sparing methods have been proposed: the radiometric system is the most important; other manual or automated systems as indicators of mycobacterial growth have been developed, while the new methods of rapid identification as high-performance liquid chromatography (HPLC) cannot be used as a routine for the high cost of equipment. Arch Virol, 1997, 142(8), 1603 - 12 Biochemical properties of protease resistant prion protein PrPsc in natural sheep scrapie; Madec JY et al.; Prions are infectious agents involved in neurodegenerative diseases, such as scrapie in sheep and goats, bovine spongiform encephalopathy (BSE) in cows and Creutzfeldt-Jakob disease (CJD) in humans . These pathogens are characterized by unusual properties, and, in particular, by their strong resistance to common procedures of disinfection used against conventional microorganisms . A major component of highly infectious fractions is a proteinase K-resistant prion protein PrPsc (PrP-res), the normal host prion protein PrPc being sensitive to PK (PrP-sen) . We used a biochemical approach to further characterize PrPsc protein in natural sheep scrapie . Western blot analyses using rabbit antiserum that recognized both normal and pathologic sheep prion proteins, were undertaken to study the biochemical behaviour of PrPsc extracted from brains of sheep naturally infected with scrapie after protease digestion and under denaturing conditions . Increasing concentrations of urea (1-7 M) or GdnSCN (0.25-3 M) and different pH from 2 to 11 were tested for their effects on protease resistance of PrPsc . Alkaline pH (pH = 10) and high concentrations of urea (> 3 M) and GdnSCN (> 0.75 M) greatly decreased the protease resistance of the prion protein . Identical experiments carried out on three different sheep from the same flock gave similar results . The biochemical behaviour of PrPsc under denaturing conditions and in the presence of proteinase K could thus provide a biochemical means for further characterization of different natural scrapie isolates. Mikrobiol Z, 1998 Mar-Apr, 60(2), 96 - 104 {Radionuclide accumulation by a microbial sorbent}; Tashirev AB et al.; Accumulation of a wide range of radionuclides by the microbial sorbent has been studied . The microbial sorbent represents granules stable in water solutions for a long period of time . The sorbent includes: concentrated biomass of metabolically active microorganisms, sources of carbon and energy, phosphorus, nitrogen, etc . Availability of nutrition sources in the sorbent provides for metabolic activity of microorganisms immobilized in granules . Metabolic activity of the sorbent was characterized . Physico-chemical sorption and metabolic activity of microorganisms lead to the extraction of a wide spectrum of radionuclides (51Cr, 54Mn, 60Co, 90Sr, 134Cs, 137Cs, 140La, 144Ce, 226Ra, 83Rb) from liquid radioactive waste . The extraction factor for some radionuclides was 10(5)-10(6) . The waste sorbent may be utilized . Absence of water phase in the ash concentrate permits the radionuclides to be buried in borosilicate or volcanic glass (accepted time of existence 10(5)-10(7) years) . The sorbent may be used to create new biotechnologies of radionuclide accumulation from water solutions. Scand J Infect Dis, 1998, 30(1), 43 - 7 The diagnostic value of gram stain of bronchoalveolar lavage samples in patients with suspected ventilator-associated pneumonia; Prekates A et al.; Ventilator-associated pneumonia (VAP) is one of the most common causes of morbidity and mortality in intensive care unit patients . However, the diagnosis is quite difficult . Gram stain (GS) of bronchoalveolar lavage (BAL) sample is a time-saving diagnostic method for VAP . However, its clinical significance has not been adequately investigated . The aim of this study was to determine its sensitivity and specificity for VAP diagnosis . We prospectively performed GS and quantitative bacterial cultures (QBC) of BAL samples, obtained through fiberoptic bronchoscope, in 75 consecutive postoperative and/or multiple trauma patients with suspected VAP . We considered BAL-GS as positive for VAP diagnosis when (i) polymorphonuclear neutrophils were > 25 per optic field at a magnification x 100 (p.o.f x 100); (ii) squamous epithelial cells were < 1% p.o.f x 100; and (iii) one or more microorganisms were seen p.o.f . at a magnification x 1,000 (p.o.f . x 1,000) . VAP was diagnosed with criteria similar to those used in previous studies . Pneumonia was the final diagnosis in 22/75 (29%) patients . The BAL-GS was positive in 17/22 patients with VAP and in 7/53 patients without VAP . Accordingly, the sensitivity of BAL-GS for VAP diagnosis was 77%, the specificity 87%, the positive predictive value 71% and the negative predictive value 90% . Our data suggest that BAL-GS has good sensitivity and high specificity for VAP diagnosis . It could therefore constitute a useful complementary tool in the task of early diagnosis and treatment of VAP. Ann N Y Acad Sci, 1998 Jun 19, 845, 57 - 71 Sphingolipids as receptor modulators . An overview; Yates AJ et al.; Glycosphingolipids are amphipathic compounds that exist mainly in the plasmalemma with their oligosaccharide portion protruding into the extracellular environment . In this position they are admirably situated for interacting with both ligands and receptors . Binding studies have demonstrated that specific glycolipids function as receptors for some microorganisms and bacterial toxins . Specific oligosaccharides on both glycolipids and glycoproteins bind members of the selection families, and some gangliosides facilitate integrins binding to their ligands . Gangliosides modulate the trophic factor-stimulated dimerization, tyrosine phosphorylation, and subsequent signal transduction events of several tyrosine kinase receptors . GM3 inhibits both the epidermal growth factor receptor and basic fibroblast factor receptor; several gangliosides except GM3 inhibit the platelet-derived growth-factor receptor; GM1 enhances nerve growth-factor-stimulated activation of TrkA; insulin receptor is inhibited to varying degrees by several gangliosides, but 2-->3 sialosylparagloboside is most effective . Activities of the beta(1)-adrenergic and delta-opioid receptors are modulated by GM1 . Available information suggests that glycolipids serve as coordinators of multiple receptor functions. J Leukoc Biol, 1998 Jul, 64(1), 108 - 13 Th1 and Th2 cytokines cooperate to stimulate mannose-receptor-mediated phagocytosis; Raveh D et al.; The mannose receptor is a macrophage surface receptor that mediates both endocytosis and phagocytosis . Previous work has demonstrated that the prototypical Th2 cytokine, interleukin-4 (IL-4), increases both cell-surface receptor expression and mannose receptor-mediated endocytosis, whereas the prototypical Th1 cytokine, interferon-gamma (IFN-gamma), decreases both surface expression and endocytosis . In many aspects of the immune response, Th1 and Th2 cytokines oppose each others' actions . We demonstrate that IL-4 and IFN-gamma alone and together enhance mannose receptor-mediated phagocytosis, despite opposing effects on cell-surface mannose receptor expression and endocytosis . Thus these usually antagonistic cytokines cooperate in increasing mannose receptor phagocytic function . The cooperative effect of these cytokines is not observed for Fc receptor-mediated phagocytosis . The Th2 cytokine IL-13 exerts similar effects to IL-4 . Our results suggest that Th1 and Th2 cytokines may act in concert at sites of inflammation to enhance mannose receptor-mediated phagocytosis of microorganisms. J Leukoc Biol, 1998 Jul, 64(1), 68 - 71 Molecular mimicry of the inflammation modulatory proteins (IMPs) of poxviruses: evasion of the inflammatory response to preserve viral habitat; Howard J et al.; Microorganisms encode numerous immunomodulators that resemble, in structure and function, molecules captured over the millennia from their hosts {G . J . Kotwal J . Leukoc . Biol . 62, 415-429} . The vaccinia virus complement control protein (VCP) was the first soluble microbial protein to have a postulated role in the immunomodulation and evasion of host defense {G . J . Kotwal and B . Moss Nature 355, 176-179} . Purified bioactive VCP has been shown to bind to C3 and C4, block the complement cascade at multiple sites {G . J . Kotwal et al . Science 250, 827-830; R . Mckenzie, G . J . Kotwal et al . J . Infect . Dis . 166, 1245-1250} and exhibit a greater potency than the human complement 4b binding protein, C4b-BP {G . J . Kotwal, Am . Biotech . Lab . 9, 76} . The importance of this protein to poxviruses was further demonstrated in rabbits and guinea pigs through the use of recombinant virus lacking an intact DNA coding for VCP {Isaacs, G . J . Kotwal, and B . Moss Proc . Natl . Acad . Sci . 89, 628-672} . Studies in mice have shown that the homolog of VCP in cowpox virus (CPV), referred to as the inflammation modulatory protein (IMP) can, in a mouse model, significantly diminish the specific footpad swelling response {C . G . Miller, S . N . Shchelkunov, and G . J . Kotwal Virol . 229, 126-133} . To determine the precise cellular changes at the site of infection, BALB/c mice were subcutaneously injected (in the backs) with CPV or a recombinant virus lacking IMP, CPV-IMP . Differences in histology were observed by staining the adjoining skin tissue sections with hematoxylin & eosin or by removal of the connective tissue and staining with May-Grunwald-Geimsa . All mice that were injected with the CPV-IMP experienced severe tissue destruction and formation of nodular lesions compared with the mice injected with CPV . Microscopic examination indicated significantly greater cellular infiltration and destruction of skeletal muscle cells in the sections of connective tissue and adjoining skin tissue, respectively, of the mice injected with the CPV-IMP {G . J . Kotwal et al . Mol . Cell . Biochem . in press} . Thus IMP preserves the tissue at the site of infection (viral habitat) . In this review, we present evidence for molecular mimicry and evolutionary relationship to other homologs of IMP and discuss their relationships with other IMPs such as the poxviral chemokine and cytokine receptor-like proteins. Aviakosm Ekolog Med, 1998, 32(2), 68 - 71 {Model study of ozone microbial decontamination effectiveness of space station environment}; Vasin VB et al.; Modeling experiments were performed to evaluate bactericide and fungicide effects of small ozone concentrations (0.3 mg/l of water and 47 mg/m3 of air) that can be generated onboard spacecraft following one hour after treatment . Over the period of treatment, reduction in aquatic microorganisms made up, depending on biotest in use, hundred and more times; concentration of atmospheric microorganisms showed a 5- to 10-fold reduction . The demonstrated effectiveness of ozone shows that it may advantage sterilization and cleaning from microorganisms a number of life support systems aboard manned space vehicles and stations. Science, 1998 Jul 10, 281(5374), 222 - 30 The Quantum Event of Oceanic Crustal Accretion: Impacts of Diking at Mid-Ocean Ridges Delaney JR, Kelley DS, Lilley MD, Butterfield DA, Baross JA, Wilcock WSD, Embley RW, Summit M. Seafloor diking-eruptive events represent the irreducible, quantum events of upper oceanic crustal accretion . They record events by which a large portion of the oceanic crust has formed through geological history . Since 1993, the U.S . Navy's real-time Sound Surveillance System has allowed location of ongoing acoustic signatures of dike emplacement and basalt eruptions at ridge crests in the northeast Pacific . These diking-eruptive events trigger a sequence of related, rapidly evolving physical, chemical, and biological processes . Magmatic volatiles released during these events may provide nutrients for communities of subseafloor microorganisms, some of which thrive in high-temperature anaerobic environments . Many of the organisms identified from these systems are Archaea . If microorganisms can thrive in the water-saturated pores and cracks within deep, volcanically active portions of our planet, other hydrothermally active planets may harbor similar life forms. J Pediatr Surg, 1998 Jun, 33(6), 880 - 4 Lipid uptake by silicone enteral access feeding devices; Trudel J et al.; BACKGROUND/PURPOSE: Deterioration of long-term enteral access devices remains a significant patient care and financial problem . Because it is known that lipids, particularly medium-chain triglycerides oil (MCT oil), can soften and break certain types of polymeric materials, the authors evaluated the effect of liquid enteral feeding formulas containing different amounts of MCT oil on silicone feeding tubes . METHODS: Commercially available and widely used gastrostomy silicone catheters of two sizes (20F and 15F) were sectioned in 5-cm-long samples and cleaned . Five groups of five pieces were immersed for 8 weeks in pure MCT oil and in four commercial formulas having similar protein, carbohydrate, and fat contents . These formulas were chosen because they contained similar percentages of fat (37% to 45%), although they contained differing amounts of MCT oil . Sodium azide 0.05% was added as a bactericide . Samples were maintained at 37 degrees C in an incubator-shaker . After incubation, specimens were rinsed, dried, and weighed . Selected samples were extracted with a chloroform-methanol solution (2:1) . Super-critical fluid chromatography (SFC) and infrared (IR) spectroscopy were performed . A tensile tester was used to generate force-elongation curves for the remaining samples . A statistical analysis (ANOVA, alpha = .05) was conducted to compare data from test groups with results from 20 samples of control silicone material . RESULTS: Data demonstrate that silicone is significantly affected by liquid formulas and pure MCT oil . SFC and IR findings indicated that fractions of MCT oil, corn oil, and canola oil were absorbed by the material . The most dramatic weight gain (3.7%) was observed for specimens immersed in pure MCT oil . An average increase (9.6%) of silicone compliance was measured along with oil migration in the tubing . CONCLUSIONS: Lipid uptake contributes significantly to deterioration of the silicone tested, leading to device failure . Surface damage can create a potential nidus for microorganisms, particularly fungi . Lipid type and rate of administration should be taken into account when long-term enteral feedings are given . These data contribute to the understanding of the causes of the physico-chemical deterioration of long-term enteral feeding devices and provide helpful information for the design and manufacture of improved products. Oral Oncol, 1998 Jan, 34(1), 39 - 43 Mucositis as a biological process: a new hypothesis for the development of chemotherapy-induced stomatotoxicity; Sonis ST; Mucositis induced by antineoplastic drugs is an important, dose-limiting and costly side effect of cancer therapy . The ulcerative lesions which result are frequent systemic portals of entry for microorganisms which inhabit the mouth and consequently are often sources of systemic infection in the myelosuppressed patient . A number of clinical observations and the inconsistency of responses to a broad range of treatment modalities suggests a physiological complexity to mucositis which has not previously been comprehensively considered . We now propose a hypothesis as to the mechanism by which mucositis develops and resolves, which is based on four phases: an initial inflammatory/vascular phase; an epithelial phase; an ulcerative/bacteriological phase; and a healing phase . The role of cytokines as initiators and ampliers of the process is discussed, as is the potential influence of genetic factors in establishing risk and modifying the course of stomatotoxicity. Rev Esp Cardiol, 1998, 51 Suppl 2, 79 - 85 {Infective endocarditis caused by unusual microorganisms}; Menasalvas A et al.; All series of infective endocarditis had a variable proportion of cases without an etiologic agent because all cultures were negative . New microbiologic techniques have permitted the discovery of the role of many microorganisms in infective endocarditis . C . burnetii is an increasing causative agent of subacute infective endocarditis . In the diagnosis, to the detection of antiphase-I antibodies, immunohistochemical, molecular techniques and cellular cultures have been added . Total cure is difficult to obtain . The combination of doxicicline plus ciprofloxacin for at least 3 years has been proposed as the treatment of choice . Surgery must be reserved for patients with cardiac insufficiency . Less than 2% of cases of acute brucellosis are complicate with infective endocarditis . Infective endocarditis produces serious and rapid valvular destruction with high mortality rates if valve surgery is not performed . For medical treatment at least 3 active agents are required . Bartonella has recently been described as an etiologic agent of infective endocarditis . It mainly affects to homeless people living in poor hygienic conditions . The aortic valve is most commonly involved and, frequently, valve insufficiency requires valve replacement . Blood culture isolation needs long incubation periods . Parenteral nutrition, immunosuppression, wide spectrum antibiotic regimens, intravenous drug addiction and cardiovascular surgery are risk factors previously described in the development of fungal endocarditis . C . albicans and Aspergillus spp . are most frequent etiologic agents . Infective endocarditis should be suspected in any patient with systemic fungal disease . Blood cultures are often negative except for Candida spp . Peripheral emboli and large vegetations are frequent . Mortality is high, antifungal therapy combined with surgery is the treatment of choice . Legionella, Mycoplasma, Chlamydia, Mycobacteria, viruses are potential agents of infective endocarditis, and difficult to diagnose because of special culture requirements . Epidemiological clues, serologic and molecular techniques and blood cultures could identify them. Rev Esp Cardiol, 1998, 51 Suppl 2, 44 - 50 {Is prophylaxis needed? Is it really effective? Risk of endocarditis after heart surgery}; Garcia Moll M et al.; Infective endocarditis still has an important morbidity and mortality in the acute phase and also in the following years . Because of this, the development and use of preventive strategies have been an important target in developed countries . Until we have some prospective studies their use will be only intuitive and based on the following criteria: endocarditis frequently follows a bacteremia; some diagnostic or therapeutic procedures cause bacteremia; the germs are habitually predictable in each procedure and are sensitive to specific antibiotics; patients with some cardiac or major structural defects have a higher risk of endocarditis . For these reasons, a rational treatment is to give the specific antibiotic against the microorganism prophylactically before it enters the bloodstream during the procedure . Although available data are inconclusive and sometimes even contradictory, most authors recommend the indication of prophylactic measures whose efficacy depends on three basic points: a) identification of patients with a high risk of endocarditis, especially those with a prosthetic cardiac valve; b) knowledge of procedures that need chemoprophylaxis, especially dental and oral procedures, and c) selection of the best prophylactic policy in each specific case . In summary, it is necessary to know to "whom", "when" and "how" to apply prophylactic measures . There are some special situations that must be considered carefully: patients treated with anticoagulant drugs or with a cardiac pacemaker or with an implanted defibrillator, patients with renal insufficiency and an arteriovenous fistulae, and some patients needing open heart surgery, or those who have already had open heart surgery . In conclusion, the prevention of bacterial endocarditis using antibiotics is currently practiced in clinical settings, especially in some specific groups of patients . It is necessary to recommend this treatment in high risk patients (i.e . in those with prosthetic cardiac valves) before a high risk procedure (i.e . dental procedures known to induce gingival or dental bleeding, including professional cleaning) and in medium risk patients, the indication must always be based on an individual analysis according to American Heart Association guidelines. Rev Neurol, 1998 Jun, 26(154), 1005 - 8 {Central nervous system infection by free-living amebas: report of 3 Venezuelan cases}; Rodriguez R et al.; INTRODUCTION: Infection of the Central Nervous System by free living amebas is an unusual event, 344 cases have been reported to date . The disease becomes evident in two different clinical fashions: Primary Amebic Meningoencephalitis (PAM) caused by Naegleria fowleri and Granulomatous Amebic Encephalitis (GAE) induced by Spp . of Acanthamoeba and Balamuthia . CLINICAL CASES: The authors report three new cases from Venezuela . Case 1 . 34 years old man, with a chief complaint of general malaise, headache and fever, a diagnosis of common cold was made and the patient was treated as such, he did not improve and was admitted to the hospital with deterioration of his clinical status; the patient died 10 days after the onset of his illness which was determined to be GAE produced by Balamuthia mandrillaris . Case 2 . 8 years old female admitted to the hospital because of fever, headache and generalized seizures of sudden onset; neurocysticercosis was diagnosed and following improvement the patient was discharged and readmitted on two occasions because of relapse and worsening of her illness, she died 2 months after the onset of her disease that was diagnosed by autopsy as GAE due to Balamuthia mandrillaris . Case 3 . 16 years old male, previously healthy, who following immersion in a water tank was admitted to the hospital because of meningeal irritation that progressed to coma and death in a 7 day lapse; autopsy revealed PAM by Naegleria fowleri . The two cases of GAE due to Balamuthia mandrillaris occurred in apparently immunocompetent individuals, contrary to the statement that these microorganisms are opportunistic . CONCLUSION: We believe that neurological infection by amphizoic amebas is being underdiagnosed, probably due to ignorance regarding this pathology or because of a very low autopsy rate in most countries. Cad Saude Publica, 1998 Apr, 14(2), 401 - 7 Blastocystosis in preschool children from bolivar city, venezuela Devera RA, Velasquez VJ, Vasquez MJ. To evaluate the prevalence of Blastocystis hominis and its clinical relevance, 169 preschool children from the 'Los Coquitos' nursery school living in Bolivar City, Venezuela, were studied . Stool samples were obtained and examined by direct microscopic examination, and the Faust and Willis concentration techniques . Some 72 of the children had intestinal parasites, of whom 32 (29.09%) had B . hominis . Prevalence for the latter was 18.93 % +/- 5.93 % . No differences were observed by sex or age (X(2) = 1.84 DF= 3; p > 0 . 05) . In the majority (53.13%) of the children, B . hominis was the only parasite . Giardia lamblia was the parasite most frequently identified with B . hominis (39.13%) . In 1994, in 12% of the cases more than five microorganisms per microscopic field were observed . Clinical manifestations were observed in 70.58% of the preschool children . Presence of parasites was not correlated with symptomatology, but only with severity . Proper clinical and parasitological response to treatment was observed in 80% and 90% of patients, respectively . The conclusion was that B . hominis is a relatively frequent intestinal parasite among the preschool children evaluated. Poult Sci, 1998 Jul, 77(7), 983 - 9 Avian macrophages: regulators of local and systemic immune responses; Klasing KC; Macrophages are key regulatory cells of the immune system involved in initiating and directing the innate and specific immune responses, the systemic acute phase response, tissue repair, and tissue remodeling . In the early stages of a challenge from invading microorganisms or from tissue injury, macrophages defend local and systemic homeostasis by initiating a complex series of cellular, biochemical, and behavioral events . These pathophysiological adjustments are mediated by an extensive variety of communication molecules, including: cytokines, cytokine inhibitors, endocrine hormones, eicosanoids, neurotransmitters, and reactive oxygen intermediates . The cytokines produced by macrophages (monokines) are not well characterized relative to their mammalian counterparts, but a variety of chemokine, pro-inflammatory, and colony-stimulating factor activities have been described . Although the sequence homology, and thus species cross-reactivity, between avian and mammalian cytokines is typically low, the functional characteristics appear to be generally similar . The pro-inflammatory cytokines are important initiators and regulators of the local immune response . They are also released in sufficient quantities during some infections to coordinate a systemic acute phase response that impacts the growth, reproduction, and well-being of poultry . An understanding of the mechanisms and molecules used by macrophages to regulate immune and inflammatory responses may permit the development of products, diets, or husbandry techniques to modulate immunity for the enhancement of the productivity of poultry. An Esp Pediatr, 1998 May, 48(5), 495 - 8 {Bacterial meningitis in pediatrics . Study of 166 cases}; Fernandez-Jaen A et al.; OBJECTIVE: The purpose of this study was to evaluate the clinical and epidemiological characteristics of meningitis in our environment . PATIENTS AND METHODS: A retrospective study of 166 cases of meningitis diagnosed in our hospital during a 10 year period (1986-1995) was performed . The patients were between 1 month and 14 years of age . RESULTS: Sixty-six percent of the patients were male and 34% female . Eleven cases were younger than 2 months (6.6%), 122 cases (73.5%) were between 3 months and 5 years of age and 33 cases (19.9%) were older than 5 years . The most frequent symptoms and signs were fever (96%), vomiting (60%), impairment of consciousness (24%) and meningeal signs (49%) . CSF cultures were positive in 52% and blood cultures in 32% . The pathogen isolated was N . meningitidis in 53 cases (32%), H . influenzae in 38 (23%), S . pneumoniae in 9 patients (5%) and others in 3 children (2%) . Meningitis due to H . influenzae increased each year . No microorganism was isolated in blood and CSF in 63 cases (38%) . Meningitis in children between 3 months and 5 years of age was due to N . meningitidis in 40 children (33%) and H . influenzae in 36 (29%) . The mortality rate was 3% . The most frequent complications were sepsis (36%) and seizures (16%) . CONCLUSIONS: The most frequently isolated agent in our study was N . meningitis . Meningitis due to H . influenzae is increasing such that H . influenzae and N . meningitis currently show similar frequency in children between 3 months and 5 years of age. Neurosci Lett, 1998 May 15, 247(2-3), 131 - 4 Melatonin restores and enhances the human type B tonsillar lymphocyte subset in recurrent acute tonsillitis; Lopez-Gonzalez MA et al.; Tonsils have a privileged situation in the immune system in that they are in touch with the environment . Melatonin is a hormone that is influenced by the circadian environmental variations of dark-light and is a modulator of the immune system . We have studied a group of thirty five children with recurrent acute tonsillitis that were submitted for tonsillectomy . Tonsillar lymphocyte subsets were determined before and after culture through flow cytometry in a tonsillar mononuclear suspension . After the culture, the lymphocyte subsets of type B suffered a decrease that was restored in the presence of melatonin or phytohemaglutinin, and even increased above the values of the control when the culture was accomplished in the presence of both substances . This process was specific for B cells, no occurrence for T lymphocytes or natural killer cells . Melatonin is found in the crossroads of the interaction of the microorganisms, pollens or inert substances with the tonsillar lymphocytes in the production of the immune defences . Further study is required on tonsillar pathology to explain its physiopathology and its possible therapeutic role. FEBS Lett, 1998 May 29, 428(3), 229 - 34 An Arabidopsis cDNA encoding a bifunctional glutamine amidotransferase/cyclase suppresses the histidine auxotrophy of a Saccharomyces cerevisiae his7 mutant; Fujimori K et al.; A cDNA encoding a glutamine amidotransferase and cyclase catalyzing the fifth and sixth steps of the histidine (His) biosynthetic pathway has been isolated from Arabidopsis thaliana . The N- and C-terminal domains of the primary structure deduced from a full-length Arabidopsis hisHF (At-HF) cDNA showed significant homology to the glutamine amidotransferase and cyclase of microorganisms, respectively . Effective suppression of the His auxotrophy of a Saccharomyces cerevisiae his7 mutant with the At-HF cDNA confirmed that the At-HF protein has bifunctional glutamine amidotransferase (HisH) and cyclase (HisF) activities. FEBS Lett, 1998 May 29, 428(3), 217 - 23 Cloning and sequencing of ISC1041 from the archaeon Sulfolobus solfataricus MT-4, a new member of the IS30 family of insertion elements; Ammendola S et al.; A genomic fragment containing the insertion sequence ISC1041 has been cloned by PCR from the archaeon Sulfolobus solfaricus MT-4, an extremophilic microorganism which grows at 87 degrees C . The 1038 bp ISC1041 element contains an imperfect 18 nt repeat and a long open reading frame which encodes a polypeptide of 311 amino acid residues . The translated amino acid sequence shows a significant similarity to IS30-like transposases . Structural analysis indicates that ISC1041 is a novel member of the IS30 family and displays the DDE motif not previously seen in Archaea . This motif is believed to be involved in the integration mechanism of many mobile elements . As this motif is present in several integrases and transposases which, despite the lack of overall protein homologies, share topological homologies to the DDE motif, a common ancestor has been proposed . The finding of an IS30-like transposase in the archaeal kingdom may have relevance for horizontal gene transfer. Immunopharmacol Immunotoxicol, 1998 May, 20(2), 199 - 209 Stress, neuropsychiatric disorders and immunological effects exerted by benzodiazepines; Covelli V et al.; Psychoneuroimmunology is a growing scientific field which deals with the mutual interplay between nervous and immune systems . In this framework, many data have demonstrated that cytokines (CKs) derived from the periphery are able to cross the blood brain barrier and act upon the central nervous system (CNS) {e.g., the hypothalamic-pituitary-adrenal axis (HPAA)}, thus regulating several physiological functions (thermoregulation, sleep, appetite) or damaging the nervous tissue, when released in exaggerated amounts . On the other hand, nervous cells, such as astrocytes and microglial cells also generate proinflammatory CKs which may be detrimental for the CNS . The neuromodulating CK network can be triggered by microorganisms and/or their products (i.e . bacterial endotoxins), but also stressful life events may activate the HPAA, thus affecting the immune system function . This review will place emphasis on some clinical conditions, such as phobia and migraine without aura (MWA), characterized by anxiety disorders . Patients affected by these neuropsychiatric alterations exhibit multiple functional deficits of phagocytes and T lymphocytes which allow penetration of various pathogens into the host . This is also supported by the detection of circulating bacterial endotoxins and the evidence of both spontaneous and induced exaggerated release of proinflammatory CKs in phobic and MWA patients . The possible iatrogenic effects of benzodiazepines (BDZ) on the immune system have been evaluated by in vitro and in vivo studies . In this respect, it emerges that diazepam exerts an inhibitory function on the immune system, while alprazolam behaves as an immunoenhancer . The presence of central and/or peripheral BDZ receptors on immune cells seems to be the key mechanism responsible for the immunomodulation exerted by these drugs. Toxicol Appl Pharmacol, 1998 Jun, 150(2), 369 - 75 Ortho-substituted polychlorinated biphenyls activate respiratory burst measured as luminol-amplified chemoluminescence in human granulocytes; Voie OA et al.; The effect of polychlorinated biphenyls (PCBs) on the activation of respiratory burst measured as luminol-amplified chemoluminescence in human granulocytes is elucidated here . Chemoluminescence was stimulated in a concentration-dependent manner (ED50 approximately 10 microM) by ortho-substituted PCB congeners, while meta- and para-substituted congeners had no significant effect . Two ortho-substituted PCB congeners were chosen for the mechanistic studies, namely 2,2',4,4'-TeCB and 2,2'-DCB, since they have been used in previous studies by others . In the absence of extracellular calcium, the respiratory burst in response to 2,2'-DCB and 2,2',4,4'-TeCB was reduced by 63% and 82%, respectively . Bisindolylmaleimide, which inhibits protein kinase C, reduced activated chemoluminescence by 2,2'-DCB, 2,2',4,4'-TeCB, N-formyl-methionyl-leucyl-phenylalanine, and phorbol 12-myristate 13-acetate . Neomycin, which inhibits phospholipase C, had a slight, but significant, effect on the 2,2',4,4'-TeCB-activated chemoluminescence but had a more pronounced effect on the 2,2'-DCB-activated chemoluminescence . 2,2'-DCB and 2,2',4,4'-TeCB significantly increased phospholipase D (PLD) activity measured as the amount of 14C-phosphatidylbutanol formed . Ethanol (1%), a phospholipase D modulator, reduced the response to 2,2'-DCB and 2,2',4,4'-TeCB by 72% and 75%, respectively . Furthermore, wortmannin (25 nM), a phosphatidylinositol 3-kinase, and genistein, a more unspecific tyrosine kinase inhibitor, reduced chemoluminescence in response to PCB . In conclusion, our results indicate that PCB-activated chemoluminescence is dependent on the Ca(2+)-dependent phospholipase D or phospholipase C, phosphatidylinositol 3-kinase, and protein kinase C activation prior to activation of the NADPH oxidase . Defects in neutrophhil functions upon exposure to PCB may render a greater susceptibility in the host to invading microorganisms or evoke inappropriate inflammatory responses leading to tissue injury. Trends Biotechnol, 1998 Jun, 16(6), 265 - 72 Using molecular techniques to identify new microbial biocatalysts; Dalboge H et al.; Evolution has favoured microorganisms that produce efficient enzymes with substrate-adapted biocatalytic activities . Progress in molecular techniques, especially expression cloning, molecular screening, protein engineering and in vivo and in vitro shuffling, have paved the way for greater speed and accuracy in cloning enzyme genes from microorganisms and generating versions with improved properties . Recently, two new approaches have been added: screening directly from uncultivated microorganisms and generating additional hits by database mining using bioinformatic tools. J Clin Microbiol, 1998 Jul, 36(7), 2063 - 7 Q fever in the Greek island of Crete: detection, isolation, and molecular identification of eight strains of Coxiella burnetii from clinical samples; Spyridaki I et al.; Over a period of 6 years (1989 to 1995), serum samples from 3,300 patients suspected to be infected by Coxiella burnetii were assayed for the presence of antibodies against antigen phase II of the microorganism by the indirect immunofluorescence antibody technique (IFAT) . One hundred fifty-two cases were recorded, and blood samples from 17 patients were cultured for the isolation of the pathogen . By a centrifugation shell vial technique, eight strains were isolated from patients suffering from acute Q fever . The microorganism was detected in the cultures by IFAT, by Gimenez staining, and by the cytopathogenic effect on Vero and human embryonic lung (HEL) cells . PCR followed by restriction fragment length polymorphism analysis was used to confirm the diagnosis and identify the Coxiella burnetii strains within the cell cultures as well as to compare them with reference strains . In order to avoid time-consuming cultures, to achieve direct detection of Coxiella burnetii in clinical samples (blood, buffy coat, etc.), and to increase the specificity and sensitivity of the detection, nested PCR was performed . The first step of DNA extraction was performed with the QIAamp blood kit 250 . For the second step of the PCR assays, the conditions of temperature and times of recycling were properly modified, and the microorganism was detected within 4 h . Our study demonstrates that Q fever is an endemic disease in Crete and that the diagnosis of Coxiella burnetii infection can be rapidly achieved by the detection of the microorganism in buffy coat samples by nested PCR . Although the presenting symptoms of the disease in this study differed from those in other studies, the Cretan strains do not differ genotypically from the reference strains (Nine Mile and Q212). Curr Opin Biotechnol, 1998 Jun, 9(3), 278 - 82 Bioenergetics of marine bacteria; Kogure K; Some marine bacteria have a special energy-transducing mechanism that is different from those found in Escherichia coli or most of the freshwater and terrestrial bacteria . These marine bacteria specifically require Na+ for their growth and utilize a Na+ circuit for various cellular functions . So far, three types of primary Na+ pump have been identified (i.e . respiration-dependent, decarboxylase-driven and Na+ ATP synthase) . Among them, the first type of Na+ pump plays the major role in the marine environment . Recently, the gene sequence and distribution of this Na+ pump have been clarified . In addition, information on genetics and the ecological significance of Na+ driven flagellar motors has also been accumulating . This recent progress in the research of the 'Na+ world' is revealing an interesting way of life that is unique to marine microorganisms. Curr Opin Biotechnol, 1998 Jun, 9(3), 270 - 7 The molecular biology of chitin digestion; Cohen-Kupiec R et al.; Chitinases catalyze the hydrolysis of chitin, an unbranched polymer of beta-1,4-N-acetylglucosamine . In recent years, soil-borne microorganisms that produce chitinases are considered as potential biocontrol agents against fungi and nematodes which causes diseases of agricultural crops . Chitinases also play an important physiological and ecological role in ecosystems as recyclers of chitin, by generating carbon and nitrogen sources . Many chitinases of varied organisms have been isolated and their corresponding genes cloned. Appl Microbiol Biotechnol, 1998 May, 49(5), 624 - 30 Rapid atrazine mineralisation in soil slurry and moist soil by inoculation of an atrazine-degrading Pseudomonas sp . strain; Wenk M et al.; The evaluation of pesticide-mineralising microorganisms to clean-up contaminated soils was studied with the widely applied and easily detectable compound atrazine, which is rapidly mineralised by several microorganisms including the Pseudomonas sp . strain Yaya 6 . The rate of atrazine removal was proportional to the water content of the soil and the amount of bacteria added to the soil . In soil slurry, 6 mg atrazine kg soil-1 was eliminated within 1 day after application of 0.3 g dry weight inoculant biomass kg soil-1 and within 5 days when 0.003 g kg soil-1 was used . In partially saturated soil (60% of the maximal water-holding capacity) 15 mg atrazine kg soil-1 was used . In unsaturated soil, about 60% {U-ring-14C} atrazine was converted to 14CO2 within 14 days . Atrazine was very efficiently removed by the inoculant biomass, not only in soil that was freshly contaminated but also in soil aged with atrazine for up to 260 days . The bacteria exposed to atrazine in unsaturated sterile soil were still active after starvation period of 240 days: 15 mg newly added atrazine kg soil-1 was eliminated within 5 days. J Perinat Med, 1998, 26(2), 123 - 4 A simple technique to isolate DNA and supernatant of genital Mycoplasma hominis and Ureaplasma urealyticum; Walther T et al.; Vaginal colonization with Mycoplasma hominis and Ureaplasma urealyticum has been implicated as a cause of prematurity . Several mechanisms to induce preterm labor have been discussed . The investigation of expressed and secreted enzymes requires a feasible method for culturing and further processing of these bacteria . We describe a simple technique for culturing of Mycoplasma hominis and Ureaplasma urealyticum without contamination with other microorganisms and isolating DNA and supernatant . PCR amplification of a chromosomal Mycoplasma fragment was performed as positive control. Respir Care Clin N Am, 1998 Jun, 4(2), 329 - 39 The role of filtration during humidification; Richards G; Nosocomial pneumonia remains an important problem in patients undergoing mechanical ventilation, being associated with high mortality and morbidity and considerable expenditure . In the past respiratory equipment has been implicated in the development of nosocomial pneumonia and strict recommendations for cleaning and maintenance have been practiced . It is now known that the circuit and other equipment rapidly become contaminated with microorganisms originating from the patient's upper airway flora . These organisms access the circuit through suctioning and coughing, and may contaminate distant sites by traveling in association with aerosols or condensate . Current evidence suggests that circuit contamination usually is a result rather than a cause of airway colonization and does not have an important role in the pathogenesis of nosocomial pneumonia . Provided that reasonable infection control measures are taken, circuit contamination does not pose a risk to the ventilated patient . Although bacterial filters placed in the circuit effectively prevent circuit contamination they do not significantly reduce the incidence of nosocomial pneumonia in patients receiving mechanical ventilation. Enferm Infecc Microbiol Clin, 1998 Apr, 16(4), 185 - 9 {Assessment of 4 commercial immunoenzymatic assays for the serologic diagnosis of Helicobacter pylori infection}; Juncal AR et al.; BACKGROUND: The aim of this study was to evaluate four commercial tests for the serologic diagnosis of infection by Helicobacter pylori based on the detection of IgG class antibodies versus this microorganism . METHODS: Four commercial kits were analyzed based on the ELISA method in serum samples of 48 patients admitted for digestive endoscopy . The data of the serologic tests were compared with those provided by the culture, the histologic observation and the urease test of gastric biopsy specimens . The calculation of seroprevalence of anti-H . pylori antibodies in serum of 60 asymptomatic subjects was carried out . RESULTS: The seroprevalence of infection by H . pylori in an asymptomatic population of between 18 to 78 years of age was 58.33% . A sensitivity of 94.3% and a specificity of 88.9% were observed with the Pyloriset EIA-G test . The positive predictive value (PPV) was 92.2% and the negative predictive value (NPV) 91.5% . With the Chemifarma commercial kit the sensitivity was 78.8% and the specificity 100% with a PPV of 100% and NPV of 76.7% . Plate showed a sensitivity of 85.3% and a specificity of 87.5% with a PPV of 90% and a NPV of 80.76% . Milenia had a sensitivity of 80% and a specificity of 66.7% and a PPV of 77% and a NPV of 70.7% . CONCLUSIONS: The usefulness of the serologic tests for the diagnosis of Helicobacter pylori infection is herein confirmed with the test evaluated showing a high sensitivity and specificity as well as high predictive values. Enferm Infecc Microbiol Clin, 1998 Apr, 16(4), 175 - 8 {Chronic necrotizing pulmonary aspergillosis: infrequent form of aspergillosis}; Navarro M et al.; BACKGROUND: Chronic necrotizing pulmonary aspergillosis (CNPA) is a chronic pulmonary infection caused by the genus Aspergillus, which usually involves moderately immunosuppressed patients . METHOD: We describe 3 patients with a toxic syndrome that had lasted several weeks or months, with lung infiltrates in the chest X-ray and the CT scan . Mycobacterium tuberculosis could not be isolated from different respiratory smears (sputum, bronchoaspiration, Barlett catheter and pulmonary punction in the third case) . Moreover, there was no response to anaerobic treatment . RESULTS: All 3 patients were moderately immunosuppressed (2 men were COPD and the woman was an asthmatic patient) . One of the men was being treated for a nocardiosis . In all three cases, A . fumigatus was isolated from de different respiratory smears . CONCLUSIONS: To diagnose a CPNA, a high degree of clinical suspicion is needed . The differential diagnose should be done with pulmonary tuberculosis and anaerobic infections . The presence of a member of the genus Aspergillus in the tracheobronchial secretions of a patient should not be systematically considered a saprofit, specially when other microorganisms can not be isolated. Infection, 1998 May-Jun, 26(3), 184 - 6 Disseminated infection with Saccharomyces kluyveri in a patient with AIDS; Pynka M et al.; A 47-year-old man with acquired immune deficiency syndrome was found to have disseminated Saccharomyces kluyveri infection . The yeast was isolated from blood and cerebro-spinal fluid . An autopsy revealed the presence of the microorganism in many organs including liver, kidneys, pancreas, spleen, lung, and brain . The case confirms a potential pathogenicity of yeasts of the genus Saccharomyces in patients with profound immune deficiency, especially in advanced HIV infection. Cell Mol Life Sci, 1998 May, 54(5), 383 - 93 Retrotransposable elements in the Dictyostelium discoideum genome; Winckler T; Repetitive DNA is a major component of any living cell . In eukaryotes retrotransposable elements make up several percent of the genome size, and consequently, retroelements are often identified in experiments aimed at establishing physical maps and whole genome sequences . In this review, recent progress in the characterization of retrotransposable elements in the genome of the eukaryotic microorganism Dictyostelium discoideum is summarized with a focus on retroelements which integrate near transfer RNA genes with intriguing position specificity. Ter Arkh, 1998, 70(5), 45 - 8 {Pathogenetic aspects of chlamydia-associated urogenic arthritis: feasibility of microorganism reproduction in cells of articular cartilage}; Panasiuk AF et al.; AIM: The study of feasibility of Chlamydia trachomatis infection and reproduction . This microorganism is an essential etiologic factor in urogenic arthritis, in chondrocytes and fibroblasts of human skin . MATERIALS AND METHODS: Infection of human skin chondrocytes and fibroblasts was made with chlamydia CP-1 strain isolated from joint fluid of the patient and serially passaged in the hen's embryo yolksacs . The inoculation results were assessed by direct staining with the use of monoclonal and fluorescent antibodies and hematoxiline . RESULTS: Chlamydial infection of human skin connective tissue, chondrocytes of the auricular cartilage and fibroblasts in particular, is possible . CONCLUSION: The findings confirm the ability of Chlamydia trachomatis to reproduce in the cartilage tissue. Quintessence Int, 1998 Apr, 29(4), 231 - 8 Autoclave performance and practitioner knowledge of autoclave use: a survey of selected UK practices; Burke FJ et al.; OBJECTIVE: It is essential that the dental surgery autoclave be tested regularly to ensure that it is operating at a temperature and pressure that will kill all microorganisms . The aims of this study were to investigate the knowledge of general dental practitioners on aspects of autoclave use, to examine their autoclaving routines, and to test the effectiveness of the sterilization cycle of their practice's autoclave . METHOD AND MATERIALS: A 35-question questionnaire was distributed to 840 dental practitioners in the United Kingdom . They were also sent three spore test ampules with details of their function and instructions on their use . The practitioners were asked to use the spore test ampules in their own practice's autoclave and to return these for testing . RESULTS: Four hundred one questionnaires and associated spore test ampules were returned for analysis, a 47.7% response rate . Eight practice autoclaves (2.0%) failed to sterilize the spores . These practices were offered a retest following counseling . A total of 77.8% of respondents had received formal training in infection control . Of the 71.3% of respondents who stated that they check the performance of their autoclave routinely, 31.5% use a chemical strip every cycle, 17.5% use it once per day, and 30.4% use it once per week . However, only five respondents (1.2%) use a spore test; two of these respondents use it every cycle, one once per day, and two once per week . CONCLUSION: Further education of practitioners may be necessary to enhance their awareness of the need for routine checking of autoclave effectiveness. Quintessence Int, 1998 Apr, 29(4), 223 - 9 The beginning of the end of the antibiotic era? Part II . Proposed solutions to antibiotic abuse; Harrison JW et al.; The bacteria causing diseases that are now becoming serious public health threats are neither strange nor exotic, but rather shockingly familiar . Tuberculosis, typhoid fever, meningitis, pneumonia, and septicemias are emerging global threats . The infectious agents causing these serious threats are the same bacteria identified many decades ago . The only difference is that these and other microorganisms are no longer killed by the "miracle drugs" that have kept them at bay for the past six decades . Antibiotic resistance has made potential killers out of bacteria that previously posed little threat to mankind . The indiscrimin