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| J Theor Biol, 1996 Aug 21, 181(4), 343 - 58 Two alternative models for spontaneous flagellar motor switching in Halobacterium salinarium; Naber H; Halobacteria are light-sensitive microorganisms which swim by means of rotating flagella . Under constant environmental conditions, they reverse their swimming direction about every 10-30 s . This is due to spontaneous switchings of the flagellar motors from clockwise to counterclockwise rotation or vice versa . However, it is unknown how the direction of rotation is regulated . In this paper, two stochastic models which could explain the characteristics of sequences of spontaneous switching events are discussed . The process is described in terms of a "motor switch" cyclically running through a sequence of states and triggering a reversal whenever a cycle is complete . Referring to previously stated hypotheses, modelling is based on the assumption that transitions between the states of the switch either occur with constant probability per unit time or are actively regulated by an endogenous biochemical oscillator . It is shown that both models yield a good description of the experimental data, though they are mutually exclusive. Ugeskr Laeger, 1996 Aug 19, 158(34), 4771 - 2 {Diagnosis of secondary aortointestinal fistulae}; Schantz V; A secondary aortoenteric fistula (SAIF) is a direct communication between the gastrointestinal (GI) tract and the aorta in a patient who has undergone major surgery on the aorta, often an aortic graft operation . The cardinal symptoms of a SAIF are septicaemia and/or GI-haemorrhage . In this case, a 40 year old man was admitted to the hospital because of repeated episodes of fever, chills and malaise . The patient had undergone an aortofemoral by-pass graft operation five years previously . Blood cultures showed repeated growth of different enteric-related microorganisms . None of the used diagnostic investigations revealed any signs of infection or fistulation near the aortic graft . After five months of hospitalization an endoscopy revealed the aortic graft protuding into the duodenal lumen, verifying the fistula . If GI-haemorrhage and/or septicaemia arise in a patient who has undergone major surgery on the aorta, one must suspect a secondary aortoenteric fistula and not hesitate too long to perform an explorative laporatomy . If untreated, the mortality rate of the condition is 100%. FEBS Lett, 1996 Aug 19, 392(1), 1 - 5 Purification and characterization of the membrane-bound nitrate reductase isoenzymes of Bradyrhizobium japonicum; Fernandez-Lopez M et al.; Two respiratory membrane-bound nitrate reductase (NR) isoenzymes, NRI and NRII, have been purified for the first time from one single microorganism . Triton X-100-solubilized NRs were purified by a three-step procedure of differential centrifugation, Q-Sepharose chromatography, and gel filtration on Sephacryl S-300 . Both isoenzymes were purified to homogeneity by the criteria of NR activity staining in polyacrylamide gels run under non-denaturating conditions and coincident staining of the protein band by silver nitrate . NRI is composed of three subunits of 116 kDa, 68 kDa, and 56 kDa, whereas NRII is composed of four subunits of 116 kDa, 68 kDa, 59 kDa, and 56 kDa . The 116-kDa subunit of NRI and the 59-kDa subunit of NRII exhibited immunological cross-reactivity with the respiratory NR of Pseudomonas stutzeri strain ZoBell. Orv Hetil, 1996 Aug 4, 137(31), 1699 - 704 {Nitric oxide . Basic research and possible clinical use}; Pronai L et al.; The journal Science considered nitric oxide (NO) the molecule of the year 1992 . This small, instable, potentially toxic gas freely crosses cell membranes . NO is produced from L-arginine by NO-synthase . The various physiological and pathological effects of NO can be explained by its reactivity and different routes of formation and metabolism . In mammals, at least three isoenzymes of NO-synthase (neuronal, endothelial and inducible forms) are known . NO exerts different effects in acidic, neutral and basic pH conditions, it is cell-protective when produced is small quantities whereas it is toxic when exceeds millimolar concentrations . Both the overproduction and suppression of NO release may have harmful effects . As a neurotransmitter, it plays important role in cell-signaling, in the erection of penis and also in the learning process . When produced by endothelial cells, it is a potent vasodilatator, and phagocytes use NO to kill microorganisms . NO also may play pathological role in chronic inflammations, immune processes and tumour generation . Based an our current knowledge, NO can be used in the therapy of pulmonary hypertension, cerebral ischemia and relaxation disturbances of smooth muscle sphincters, and the blockade of NO synthase activity may help in the management of septic shock, hypotension and inflammations. Pract Periodontics Aesthet Dent, 1996 Aug, 8(6), 581 - 4; quiz 584 Clinical management of infected root canal dentin; Love RM; Several hundred different species of bacteria are present in the human intraoral environment . Bacterial penetration of root canal dentin occurs when bacteria invade the root canal system . These bacteria may constitute a reservoir from which root canal reinfection may occur during or after endodontic treatment . The learning objective of this article is to review endodontic microbiology, update readers on the role of bacteria in pulp and periapical disease, and discuss the principles of management of infected root canal dentin . Complete debridement, removal of microorganisms and affected dentin, and chemomechanical cleansing of the root canal are suggested as being the cornerstones of successful endodontic therapy, followed by intracanal medication to remove residual bacteria, when required. Genetika, 1996 Aug, 32(8), 1061 - 7 {Mutator genes of the yeast Saccharomyces cerevisiae . Interaction of mutations him and his with mutations blocking three principal pathways of repair of induced DNA damage}; Koval'tsova SV et al.; During recent years, genes controlling mutation in higher eukaryotes have been found to be involved actively in carcinoma regeneration in cells . In this respect, studying the genetic control of mutagenesis becomes a key direction of research into mechanisms responsible for cancer generation . The results of studying interaction of mutations in the HIM and HSM genes, controlling spontaneous and induced mutagenesis in yeasts, and mutations impairing three known pathways of DNA damage repair in this microorganism, are described in this work . It was shown that mutation rev3 completely blocks UV-induced mutagenesis in all mutants studied . On the other hand, mutation rad2 synergistically interacts with mutations him1, hsm1, hsm3, hsm6, and hsm2, thus enhancing the frequency of UV-induced mutagenesis in double mutants multiple times . Mutations him2 and him3 manifested epistatic interaction with mutation rad2 . With mutation rad54, the interaction was epistatic for mutations him1 and hsm2 and was additive for mutations hsm1, him2, and him3 . On the basis of the data obtained, we developed a scheme for the appearance of mismatch bases in the process of repair of UV-induced DNA damage. Eur J Oral Sci, 1996 Aug, 104(4 ( Pt 1)), 327 - 34 Emotional stress effects on immunity, gingivitis and periodontitis; Breivik T et al.; Gingivitis and periodontitis are thought to result from an imbalance between those oral microorganisms which normally colonize tooth surfaces in close contact with the gingival margin, and the nature and efficiency of the host response . The bacteria are the triggering agents, but host defence mechanisms within the gingival/periodontal tissues seem to be responsible for most of the tissue damage and for the outcome and progression of the diseases . It has recently been shown that emotional or psychological load (stress) may influence immune activities directly via nerve messenger substances (neurotransmitters and neuropeptides) and/or indirectly via neuroendocrine (hormone) substances . This review discusses how emotional stressors and nervous and neuroendocrine responses to psychological stressors may modulate the immune response to bacteria, and thus be expected to influence the progression and course of gingivitis and periodontitis. Dermatol Nurs, 1996 Aug, 8(4), 287 - 95 The value and limitations of protective gloves in medical health service: part II; Mellstrom GA et al.; The value of protective gloves in the health care environment is well known . However, these gloves are not perfect . Some are permeable to microorganisms and various chemicals, and/or result in side effects for health care professionals . Gloves that offer the greatest protection and least side effects are highly desirable . Protection against microorganisms and protection against chemicals used in health care are described in Part II of this three-part series. Zentralbl Bakteriol, 1996 Aug, 284(4), 540 - 9 Evaluation of commercial kits for quantitative identification and tests on antibiotic susceptibility of genital mycoplasmas; Abele-Horn M et al.; In this study, commercial media and kits for identification and tests for antibiotic susceptibility of genital mycoplasmas were evaluated in comparison to standardized methods . A total of 298 specimens was routinely enrolled . Our results showed that all media corresponded for qualitative and semiquantitative identification with a specificity of 100% for both microorganisms and a sensitivity of 94% for U . urealyticum and of 88% for M . hominis . Standard methods were superior to commercial kits for qualitative and quantitative identification (sensitivity 85-97% for U . urealyticum and 79-83% for M . hominis) . There were large discrepancies when testing antibiotic susceptibility. Vet Parasitol, 1996 Aug, 64(1-2), 71 - 82 Irradiation as a cold pasteurization process of food; Loaharanu P; A number of emerging pathogenic microorganisms and parasites in food, the wide publicity of outbreaks of foodborne diseases and the increasing number of immuno-compromised population have resulted in a need to develop proper strategies and technologies to protect health of consumers . Regulations in most countries which are promulgated to ensure safety of foods, are not properly enforced to protect consumers' health especially with regard to food of animal origin . While regulations are in place and properly enforced for liquid foods such as milk or fruit juices, more solid foods especially those of animal origin, e.g . poultry, meat and seafood, which are often contaminated by pathogenic microorganisms and parasites, are not similarly regulated . The number of incidences of foodborne diseases can the subsequent economic impact to the society can be enormous . Recently, an increasing number of national and international organizations have recognised the use of irradiation as a method to ensure hygienic quality of more solid food of animal origin in the same manner as thermal pasteurization does for liquid foods . The effectiveness of irradiation as a cold pasteurization method to control foodborne disease caused by pathogenic microorganisms and parasites, especially in food to be consumed raw or partially processed, is established . Its role in overcoming trade barriers of food of animal origin based on the principle of the Agreement on the Application of Sanitary and Phytosanitary Measures, adopted during the GATT Uruguay Round will be discussed. Tissue Antigens, 1996 Aug, 48(2), 127 - 35 Apoptosis following interleukin-2 withdrawal from T cells: evidence for a regulatory role of CD18 (beta 2-integrin) molecules; Ropke C et al.; Following a successful immune response against invading microorganisms, the majority of activated T cells is eliminated, while a minor fraction survives as memory T cells . A decline in T lymphocyte growth factors such as interleukin-2 (IL-2) appears to play a role in the elimination of previously activated T cells . Thus, removal of IL-2 from proliferating T cells not only induces growth arrest, but triggers a massive cell death due to apoptosis . While the apoptotic response involves a series of well-described events, it remains less clear how apoptosis is regulated following IL-2 withdrawal . Here, we provide evidence that CD18 molecules (beta 2-integrins) play a regulatory role in the apoptotic response following removal of IL-2 from previously activated, antigen specific CD4+ T cell lines . Thus, CD18 mAb inhibited the apoptotic response to IL-2 deprivation, whereas mAb against other adhesion molecules (CD28, CD29, CD49d, CD80, CD86) did not . Secondly, IL-2 withdrawal resulted in a retarded apoptotic response in LFA-1 (CD11a/CD18) negative T cells obtained from a leukocyte adhesion deficiency (LAD) patient, as compared to LFA-1 positive T cell lines . Thirdly, co-culture of LFA-1 positive- and negative-T cells at different ratios induced apoptotic responses that were higher than expected, had the two lymphocyte populations not been interacting and significantly higher than that seen in pure LFA-1 negative T cells . Supernatants from LFA-1 positive T cell cultures undergoing apoptosis did not induce an enhanced apoptotic responses in LFA-1 negative T cells, and, reversely, culture supernatants from LFA-1 negative T cells did not rescue LFA-1 positive cells from undergoing apoptosis . The apoptotic response was partly blocked by IL-15, a newly identified T cell growth factor . Taken together, these findings suggest that CD18 molecules (beta 2-integrins) play a regulatory role in the apoptotic response following cytokine withdrawal, and that the regulation is mediated, at least partly, through T-T cell interactions . Thus, apoptotic death following IL-2 deprivation appears to be under "social" control by surrounding T cells. J Dairy Sci, 1996 Aug, 79(8), 1476 - 86 Do ruminal bacteria exchange genetic material? Morrison M. This paper discusses the reasons and current evidence for gene transfer between ruminal bacteria and other bacteria in the environment, possible routes for genetic exchange, and candidate genes . Gene transfer between ruminal bacteria has been demonstrated in vitro; however, success has been only minimal in obtaining plasmids and other self-transmissible genetic material from ruminal bacteria . The application of molecular biology techniques with ruminal microorganisms should permit the opportunity for an in vivo assessment of gene transfer . Studies that could provide pertinent information for ruminal microbiologists and dairy nutritionists are outlined. Int J Food Microbiol, 1996 Aug, 31(1-3), 263 - 71 Characteristics of a multicomponent first-order model for thermal inactivation of microorganisms and enzymes; Fujikawa H et al.; There are several mathematical models that express different types of non-linear thermal inactivation of microorganisms and enzymes . Among the models the characteristics of a multicomponent first-order model were studied on a calculative simulation . For the initial period of inactivation the pattern of the model was predominantly affected by the kinetics of the component with the highest initial concentration . For longer periods of inactivation the pattern was predominantly affected by the kinetics of the component whose rate constant was the lowest . It was also found that the observation period affected the apparent pattern of the model . The estimation method of parameter values of the model from inactivation curves was then studied. Int J Food Microbiol, 1996 Aug, 31(1-3), 45 - 58 Fluorogenic and chromogenic enzyme substrates in culture media and identification tests; Manafi M; Rapid detection and identification of microorganisms is extremely important in many fields of applied and research microbiology . In general, fluorogenic and chromogenic substrates have proved to be a powerful tool, utilizing specific enzymatic activities of certain microorganisms, either in parallel with or instead of traditional methods . By incorporation of synthetic fluorogenic or chromogenic substrates into primary selective media, enumeration and detection can be performed directly on the isolation plate . The introduction of many of these media and identification tests has led to improved accuracy and faster detection of target organisms, often reducing the need for isolation of pure cultures and confirmatory tests. Eur Respir J, 1996 Aug, 9(8), 1729 - 35 Stomach as a source of colonization of the respiratory tract during mechanical ventilation: association with ventilator-associated pneumonia; Torres A et al.; The aetiopathogenesis of ventilator-associated pneumonia (VAP) requires abnormal oropharyngeal and gastric colonization and the further aspiration of their contents to the lower airways . VAP develops easily if aspiration or inoculation of microorganisms occur in patients with artificial airways, in whom mechanical, cellular and/or humoral defences are altered . Well-known risk factors for gastric colonization include: alterations in gastric juice secretion; alkalinization of gastric contents; administration of enteral nutrition; and the presence of bilirubin . However, the role of the colonized gastric reservoir in the development of VAP remains debatable . Evidence in favour of the role of the stomach in the development of VAP comes mainly from randomized, controlled trials of selective gut decontamination and stress ulcer prophylaxis in the intensive care unit (ICU), in which reducing the bacterial burden of the stomach decreases the incidence of nosocomial respiratory infections . However, at least three studies of flora have found an absence of stomach origin of pneumonia occurring during mechanical ventilation . Prophylactic measures suggested to prevent VAP in relation to the gastric reservoir include: treatment for stress ulcers with sucralfate; prevention of duodenal reflux with metoclopramide; reduction of gastric burden and bacterial translocation by selective digestive decontamination; acidification of enteral feeding; and jejunal feeding . Gastro-oesophageal reflux can be prevented by using small bore nasogastric tubes and jejunal feeding . The aspiration of gastric contents can be reduced by positioning patients in a semirecumbent position, checking the patency of the tube cuff, and aspiration of subglottic secretions . The role of the stomach as a reservoir for microorganisms causing ventilator-associated pneumonia is still controversial but despite the debate, there is major evidence in the literature in favour of the gastric origin of part of these pulmonary infections. Proteins, 1996 Aug, 25(4), 456 - 72 Evolution of beta-amylase: patterns of variation and conservation in subfamily sequences in relation to parsimony mechanisms; Pujadas G et al.; Soybean and sweet potato beta-amylases are structured as alpha/beta barrels and the same kind of folding may account for all known beta-amylases . We provide a comprehensive analysis of both protein and DNA (coding region) sequences of beta-amylases . The aim of the study is to contribute to the knowledge of the evolutionary molecular relationships among all known beta-amylases . Our approach combines the identification of the putative eightfold structural core formed by beta-strands with a complete multi-alignment analysis of all known sequences . Comparing putative beta-amylase (alpha/beta)8 cores from plants and microorganisms, two differentiated versions of residues at the packing sites, and a unique set of eight identical residues at the C-terminal catalytical site are observed, indicating early evolutionary divergence and absence of localized three-dimensional evolution, respectively . A new analytical approach has been developed in order to work out conserved motifs for beta-amylases, mostly related with the enzyme activity . This approach appears useful as a new routine to find sets of motifs (each set being known as a fingerprint) in protein families . We demonstrate that the evolutionary mechanism for beta-amylases is a combination of parsimonious divergence at three distinguishable rates in relation to the functional signatures, the barrel scaffold, and alpha-helix-containing loops. Oral Surg Oral Med Oral Pathol Oral Radiol Endod, 1996 Aug, 82(2), 218 - 24 Pathohistology of undecalcified primary teeth in vitamin D-resistant rickets: review and report of two cases; Hillmann G et al.; The basic dental defects in vitamin D-resistant rickets seem to be manifested in dentin . Enamel is usually reported to be normal . This histologic examination showed the penetration of microorganisms through the calcified structures of the enamel layer without visible caries . The microorganisms passed through the dentinoenamel junction and invaded dentin, which was characterized by calcospherites and large amounts of interglobular dentin . Furthermore, microorganisms could be detected in dentinal tubules, which were exposed to the oral cavity when enamel was removed . However, large areas of tertiary dentin extended between such tubules and the pulp . These light microscopic results suggest that clinical manifestations, such as, pulp recrosis and periapical lesions (without carious defects) may be caused by the penetration of microorganisms through microclefts of the enamel layer as well as pathologically altered enamel microstructures of affected teeth. Exp Appl Acarol, 1996 Aug, 20(8), 421 - 34 Wolbachia: intracellular manipulators of mite reproduction; Breeuwer JA et al.; Cytoplasmically transmitted Wolbachia (alpha-Proteobacteria) are a group of closely related intracellular microorganisms that alter reproduction in arthropods . They are found in a few isopods and are widespread in insects . Wolbachia are implicated as the cause of parthenogenesis in parasitic wasps, feminization in isopods and reproductive (cytoplasmic) incompatibility in many insects . Here we report on the widespread occurrence of Wolbachia in spider mites and predatory mites based on a PCR assay for a 730 bp fragment of the ftsZ gene with primers that are specific for Wolbachia . An additional PCR, using two primer pairs that amplify a 259 bp region of the ftsZ gene that are diagnostic for the two Wolbachia subdivisions A and B, showed that infected mites only carried type B and not type A Wolbachia . The fact that some species tested negative for Wolbachia does not mean that the entire species is uninfected . We found that natural populations of Tetranychus urticae are polymorphic for the infection . The possible effects of Wolbachia on mite reproduction and post-zygotic reproductive isolation are discussed. Appl Biochem Biotechnol, 1996 Aug, 60(2), 97 - 106 Determination of cyanide using a microbial sensor; Nakanishi K et al.; A microbial cyanide sensor was prepared, consisting of immobilized Saccharomyces cerevisiae and an oxygen electrode . When the electrode was inserted into a solution containing glucose, the respiration activity of the microorganisms increased . The change in the respiration activity is monitored with the oxygen electrode . When cyanide is added to the sample solution, the electron transport chain reaction of the respiration system in the mitochondria is inhibited, resulting in a decrease in respiration . The inhibition is caused by cyanide binding with respiration enzymes such as the cytochrome oxidase complex in the mitochondrial inner membrane . Therefore, the cyanide concentration can be measured from the change in the respiration rate . When the sensor was applied to a batch system at pH 8.0 and 30 degrees C, the cyanide calibration curve showed linearity in the concentration range between 0.3 microM and 150 microM CN-. New Horiz, 1996 Aug, 4(3), 333 - 7 A model of the transmission of antibiotic-resistant bacteria in the intensive care unit; Barza M; Antibiotic resistance is a growing problem, affecting microorganisms found both in hospitals and in the community . In most patients, resistant organisms arise by transmission of already resistant microorganisms from another person, rather than arising by mutation in the index patient . Antibiotic resistance genes are often borne on plasmids or transposons on which they may be spread rapidly to other organisms in the same species or in other species . Plasmids and transposons readily pick up genes for resistance to other antibiotics or nonantibiotic agents ("linked resistance") . Control of the spread of antibiotic resistance may require limitation of the usage of other agents with linked resistance as well as of the antibiotics of primary interest . A model is described for the analysis of the transmission of antibiotic-resistant enteric bacteria in the ICU . The model deals with the baseline level of antibiotic resistance in the "source" patient, the effect of antibiotics in augmenting the concentration of resistant organisms in that patient, the role of patient-to-patient contact, and factors which may influence the "colonizability" of the recipient patient . Possible measures to reduce the spread of antibiotic resistance are discussed . It is hoped that the model may serve to focus discussion on some key ingredients of the transmission cycle. Am J Ind Med, 1996 Aug, 30(2), 142 - 7 Industrial hygiene measurements in a new industry: the repulping and deinking of paper waste; Rix BA et al.; Six Danish paper recycling plants were included in an assessment of exposure to chemicals . A questionnaire on processes was completed, and in-plant industrial hygiene measurement data collected 1982-1994 were examined . The assessment of chemicals did not reveal a major use of possible carcinogens, but acrylamide may have been released in the work environment in one plant . A total of 197 hygiene measurements were recorded: 126 in the largest plant . Airborne concentrations of dust, microorganisms, and endotoxins varied widely between plants . High concentrations of dust were recorded in the paper machine area in one plant and in the repulping unit in another plant . In general, endotoxin levels were low, but endotoxin levels were increased in one plant when reuse of process water was intensified . Changes in procedures should be assessed by industrial hygiene measurements. J Antibiot (Tokyo), 1996 Aug, 49(8), 752 - 7 Heliquinomycin, a new inhibitor of DNA helicase, produced by Streptomyces sp . MJ929-SF2 I . Taxonomy, production, isolation, physico-chemical properties and biological activities; Chino M et al.; Heliquinomycin was isolated as a part of a program designed to find inhibitors of DNA helicase from microbial sources . It was purified from the culture broth of Streptomyces sp . MJ929-SF2 by solvent extraction and serial chromatographies of centrifugal partition chromatography, Sephadex LH-20 and Capcell Pak C18 (HPLC) . The isolated red powder was analyzed to have the molecular formula of C33H30O17 . It inhibited partially purified DNA helicase from HeLa cell in a non-competitive manner with the inhibition constant (Ki) of 6.8 mM . Heliquinomycin exhibited biological activity against microorganisms including MRSA, and cultured cell lines. Biochem Mol Med, 1996 Aug, 58(2), 151 - 5 Detection of Actinomyces species using nonradioactive riboprobes coupled with polymerase chain reaction; Kiyama M et al.; We have been focusing our attention on the detection and identification of oral bacteria which are frequently associated with periodontal disease . In previous studies, Actinomyces species-specific riboprobes were generated and used to identify this microorganism . However, problems lie in the low sensitivity of this method . We have developed a novel system for the detection of Actinomyces species using nonradioactive riboprobes coupled with polymerase chain reaction (PCR) in this study . This system employs two procedures; initially, DNA fragments specific for the target microorganism are amplified by PCR, and these specific fragments are further hybridized with nonradioactive riboprobes . PCR analysis using chromosomal DNA isolated from Actinomyces species including laboratory strains, clinical isolates, and Actinomyces naeslundii (ATCC 12104) indicated the presence of the predicted common 756-bp fragment, a portion of the sialidase gene . These amplified DNA fragments were effectively visualized by hybridization with the digoxigenin-labeled riboprobes corresponding to the internal region of the amplified sialidase gene . With this system, approximately three orders of magnitude less chromosomal DNA was sufficient for the detection of specific microorganisms compared to the conventional riboprobe systems. Insect Mol Biol, 1996 Aug, 5(3), 217 - 21 Molecular identification of a Wolbachia endosymbiont in a Tetranychus urticae strain (Acari: Tetranychidae); Tsagkarakou A et al.; Wolbachia, a maternally inherited bacterium, is involved in alterations of arthropod sexuality . Reproductive incompatibilities are often observed in miles, but the existence of this microorganism in their cytoplasm has not yet been demonstrated . We identified the presence of Wolbachia in a strain of the spider mite Tetranychus urticae based on the amplification and sequencing of part of the 16S rDNA and ftsZ genes . In order to establish the phylogenetic relationships between Wolbachia found in T . urticae and in other arthropods, we aligned the resulting sequences with already published ones . For both 16S and ftsZ genes the Wolbachia carried by T . urticae clustered together with Wolbachia found in other arthropods. Can J Microbiol, 1996 Aug, 42(8), 875 - 9 A novel fluorochrome for the microscopic observation of microbial morphology in wet mounts; Chan EC et al.; A family of novel nontoxic fluorochromes, including trans-4-(p-N,N-dimethylaminostyryl)-N-butoxycarbonyl-methylpyridin ium bromide and other dimethylaminostyrylpyridinium salts, has been used for the examination of microorganisms in the living state . Equipment required is similar to that for immunofluorescence, but the technique does not necessitate the utilization of specific antibodies . Procaryotic vegetative cells and endospores were readily visualized by their fluorescence with no observable quenching . Other bacteria observed included capsule-forming species, acid-fast mycobacteria, and spirochetes . In addition, the technique is also applicable to the examination of eucaryotic microorganisms . The technique as described is simple and convenient, and serves as an alternate means for the microscopic study of viable microorganisms. Eur J Biochem, 1996 Aug 1, 239(3), 835 - 41 cDNA cloning of mouse nebulin . Evidence that the nebulin-coding sequence is highly conserved among vertebrates; Zhang JQ et al.; Nebulin is a family of giant myofibrillar proteins with molecular masses ranging over 700-900 kDa . Using a human nebulin cDNA probe, we isolated three nebulin cDNA clones from a mouse skeletal muscle cDNA library . These three clones, labeled 8c . 7a and 4b . carry inserts of 2.0, 3.0 and 3.5 kb, respectively . In Northern blots, each insert detected the same approximately = 25 kb message from skeletal muscle as the human nebulin probe, while detecting no messages from cardiac muscle . Sequence data in combination with reverse-transcriptase PCR indicates that clones 7a and 8c overlap to form 4076 bp contiguous sequence . Alignment with the published full-length human nebulin sequence indicates that clone 4b overlaps with clone 7a over 1596 bp . However, after the first 798-bp overlap, the sequence of these two mouse nebulin clones diverge, suggesting that they derive from distinct transcripts encoding isoforms of mouse nebulin . The mouse nebulin clones encode a series of = 245-residue super repeats, each of which can be subdivided into seven = 35-residue, weakly repeating modules centered around a conserved tyrosine residue, consistent with the human nebulin sequence . The mouse nebulin clones align along the central third of the full-length human sequence, corresponding to super repeats 8-16 of the 22 super repeats found in human nebulin . The translated sequence is greater than 90% identical to the human sequence, with the exception of a 200-amino-acid region at the C-terminus of clone 4b, which is less than 60% identical . In genomic Southern blots, a mouse nebulin probe detected a homologous sequence in a wide variety of vertebrate species under stringent conditions . However, no significant hybridization was observed to genomic DNA from invertebrates and microorganisms, even under very low stringency . The sequence and Southern-blot data suggest that the nebulin sequence is highly conserved among vertebrate species. Microbiology, 1996 Aug, 142 ( Pt 8), 1927 - 35 Growth rate control of protein and nucleic acid content in Streptomyces coelicolor A3(2) and Escherichia coli B/r; Shahab N et al.; Escherichia coli possesses regulatory mechanisms that coordinate cell growth with the synthesis of essential macromolecules (protein, RNA and DNA) . While fundamental differences have been identified in the growth habit and chromosome structure of E . coli and Streptomyces, little is known about these regulatory mechanisms in filamentous bacteria . This paper reports on the relationship between the macromolecule content of S . coelicolor A3(2) and its specific growth rate . The protein, RNA and DNA contents (g per 100 g biomass) of S . coelicolor A3(2) grown in steady-state continuous culture over a range of specific growth rates (0.025-0.3 h-1) were 31-45, 10-22 and 3.5-4.5% (w/w), respectively . This composition is qualitatively similar to that of other microorganisms . Changes in the macromolecular content of S . coelicolor A3(2) and E . coli B/r with specific growth rate appear to be essentially similar . However, the data indicate that the RNA content of S . coelicolor A3(2), grown under the conditions used, exceeds that of E . coli grown at the same specific growth rate . The data also suggest that overlapping rounds of replication are not a feature of DNA synthesis in S . coelicolor A3(2) . This may be a function of the organism's low maximum specific growth rate . Alternatively, it may be a consequence of regulatory mechanisms which act to inhibit the initiation of DNA synthesis in a linear chromosome which is already undergoing replication. Toxicol Lett, 1996 Aug, 86(2-3), 79 - 83 Chemicals and proteins as allergens and adjuvants; Kapsenberg ML; Small molecular weight chemicals may irritate tissues via the induction of the production of various proinflammatory and chemotactic molecules . The structure of these irritants is heterogenous, as is the pattern of their effects . Chemicals are potentially allergenic (i.e . haptens) when they are able to bind proteins such as immune response molecules . Sensitization will occur when these haptens additionally induce irritation resulting from an intrinsic adjuvant's activity of the chemical . In most cases haptens induce the activation of hapten-specific T cells with a type 1 cytokine profile mediating delayed hypersensitivity . A limited number of haptens induce the production of type 2 cytokines in T cells and, consequently, allergic reactions after inhalation . Similarly, inhaled proteins become allergenic when they activate protein allergen-specific T cells producing type 2 cytokines . In many individuals this cytokine profile is associated with atopy . It must be expected, however, that a type 2 cytokine profile can also be inflicted by the action of various adjuvants types, such as biologically active small molecular weight chemicals and proteins (i.e . enzymes) and microorganisms, thereby promoting allergic reactions. Ann N Y Acad Sci, 1996 Jul 23, 791, 314 - 7 Preharvest food safety; Childers AB et al.; Preharvest food safety is essential for the protection of our food supply . The production and transport of livestock and poultry play an integral part in the safety of these food products . The goals of this safety assurance include freedom from pathogenic microorganisms, disease, and parasites, and from potentially harmful residues and physical hazards . Its functions should be based on hazard analysis and critical control points from producer to slaughter plant with emphasis on prevention of identifiable hazards rather than on removal of contaminated products . The production goal is to minimize infection and insure freedom from potentially harmful residues and physical hazards . The marketing goal is control of exposure to pathogens and stress . Both groups should have functional hazard analysis and critical control points management programs which include personnel training and certification of producers . These programs must cover production procedures, chemical usage, feeding, treatment practices, drug usage, assembly and transportation, and animal identification . Plans must use risk assessment principles, and the procedures must be defined . Other elements would include preslaughter certification, environmental protection, control of chemical hazards, live-animal drug-testing procedures, and identification of physical hazards. Ann N Y Acad Sci, 1996 Jul 23, 791, 136 - 47 Reactive oxygen and nitrogen intermediates and products from polyamine degradation are Babesiacidal in vitro; Johnson WC et al.; Products released from activated macrophages have been demonstrated to have microbicidal activity against a variety of microorganisms . Reactive oxygen intermediates (ROI) and reactive nitrogen intermediates (RNI) have been shown to affect the induction of degenerate (crisis) forms of Plasmodium spp . Polyamines are degraded into acrolein which has also been shown to be toxic to Plasmodium spp . We have investigated the possibility that these products act similarly with Babesia bovis . Crisis forms of B . bovis developed in erythrocyte cultures after the introduction of supernatants containing ROI, RNI, and acrolein . Xanthine degradation by xanthine oxidase leads to the formation of superoxide anion, hydrogen peroxide, and hydroxyl radicals . The degradation in the presence of B . bovis was toxic to the parasite . The toxicity was partially reversed by the addition of the ROI scavenger catalase . However, H2O2 added directly had little effect, suggesting a role for the other ROI products . Spermine degradation by polyamine oxidase and direct addition of acrolein was toxic in a dose-dependent manner . Finally, spontaneous generation of nitric oxide from sodium nitroprusside or S-nitroso-N-acetyl-penicillamine was also toxic in a dose-dependent manner . These data lead us to suggest a role for activated macrophages in the primary immune response against B . bovis. Proc Natl Acad Sci U S A, 1996 Jul 23, 93(15), 7979 - 84 16S rRNA genes reveal stratified open ocean bacterioplankton populations related to the Green Non-Sulfur bacteria; Giovannoni SJ et al.; Microorganisms play an important role in the biogeochemistry of the ocean surface layer, but spatial and temporal structures in the distributions of specific bacterioplankton species are largely unexplored, with the exceptions of those organisms that can be detected by either autofluorescence or culture methods . The use of rRNA genes as genetic markers provides a tool by which patterns in the growth, distribution, and activity of abundant bacterioplankton species can be studied regardless of the ease with which they can be cultured . Here we report an unusual cluster of related 16S rRNA genes (SAR202, SAR263, SAR279, SAR287, SAR293, SAR307) cloned from seawater collected at 250 m in the Sargasso Sea in August 1991, when the water column was highly stratified and the deep chlorophyll maximum was located at a depth of 120 m . Phylogenetic analysis and an unusual 15-bp deletion confirmed that the genes were related to the Green Non-Sulfur phylum of the domain Bacteria . This is the first evidence that representatives of this phylum occur in the open ocean . Oligonucleotide probes were used to examine the distribution of the SAR202 gene cluster in vertical profiles (0-250 m) from the Atlantic and Pacific Oceans, and in discrete (monthly) time series (O and 200 m) (over 30 consecutive months in the Western Sargasso Sea . The data provide robust statistical support for the conclusion that the SAR202 gene cluster is proportionately most abundant at the lower boundary of the deep chlorophyll maximum (P = 2.33 x 10(-5)) . These results suggest that previously unsuspected stratification of microbial populations may be a significant factor in the ecology of the ocean surface layer. Proc Natl Acad Sci U S A, 1996 Jul 23, 93(15), 7944 - 9 Induction of mucosal immune responses against a heterologous antigen fused to filamentous hemagglutinin after intranasal immunization with recombinant Bordetella pertussis; Renauld-Mongenie G et al.; Live vaccine vectors are usually very effective and generally elicit immune responses of higher magnitude and longer duration than nonliving vectors . Consequently, much attention has been turned to the engineering of oral pathogens for the delivery of foreign antigens to the gut-associated lymphoid tissues . However, no bacterial vector has yet been designed to specifically take advantage of the nasal route of mucosal vaccination . Herein we describe a genetic system for the expression of heterologous antigens fused to the filamentous hemagglutinin (FHA) in Bordetella pertussis . The Schistosoma mansoni glutathione S-transferase (Sm28GST) fused to FHA was detected at the cell surface and in the culture supernatants of recombinant B . pertussis . The mouse colonization capacity and autoagglutination of the recombinant microorganism were indistinguishable from those of the wild-type strain . In addition, and in contrast to the wild-type strain, a single intranasal administration of the recombinant strain induced both IgA and IgG antibodies against Sm28GST and against FHA in the bronchoalveolar lavage fluids . No anti-Sm28GST antibodies were detected in the serum, strongly suggesting that the observed immune response was of mucosal origin . This demonstrates, to our knowledge, for the first time that recombinant respiratory pathogens can induce mucosal immune responses against heterologous antigens, and this may constitute a first step toward the development of combined live vaccines administrable via the respiratory route. Front Biosci, 1996 Jul 01, 1, d72 - 90 Interactions between the components of the human NADPH oxidase: a review about the intrigues in the phox family; Leusen JH et al.; When microorganisms invade the body, they encounter a large asssortment of defense mechanisms . Among these, phagocytes play an important role in the process of killing pathogens . This event is mediated by two important processes, viz . activation of the NADPH oxidase enzyme, which leads to the production of toxic oxygen metabolites, and fusion of intracellular granules with the phagosome (the vesicle that contains the ingested micro-organisms), which causes release of the toxic granule contents into this vesicle . The human NADPH oxidase is a very complex enzyme, in two ways: 1 . it exists of at least 6 components: cytochrome b558 (a heterodimer comprised of gp91-phox and p22-phox), p47-phox, p67-phox, p40-phox, rac and Rap1A, and 2 . there are multiple signal transduction pathways leading to activation of the NADPH oxidase . The most likely reason for this complexity is the toxicity of the oxygen radicals produced by the active NADPH oxidase; these compounds are not only harmful to the invading pathogens, but also to the surrounding tissues . This latter effect is enforced by the activation of metalloproteases released by neutrophils and by oxidation of protease inhibitors by oxygen metabolites . Therefore, an improper activation of the NADPH oxidase must be prevented at all costs and, when the infection has been cleared, a rapid deactivation mechanism is imperative . In this review, the interaction between the different components of the NADPH oxidase and the activation of these proteins will be discussed. Mycoses, 1996 Jul-Aug, 39(7-8), 279 - 82 Partial characterization of proteolytic enzymes of Microsporum canis and Microsporum cookei; Simpanya MF et al.; Characterization by proteinase inhibitors of the enzymes produced by Microsporum spp . revealed that Microsporum canis and Microsporum cookei produce serine proteinase(s), but only M . canis expresses aspartic and cysteine proteinases and probably a metalloproteinase . Both M . canis and M . cookei expressed metalloelastinolytic proteinases . All the proteinase types have been implicated in the pathogenicity of a wide range of microorganisms. Rev Environ Health, 1996 Jul-Sep, 11(3), 149 - 65 Recombinant DNA technology: a 20-year occupational health retrospective; Cohen R et al.; During the past 20 years of recombinant DNA research and its commercial applications, neither unique occupational-health risks nor adverse effects from accidental occupational recombinant microorganisms has been reported . Such injuries as acid splashes, CNS-depressant effects from over-exposure to solvents, and infections may occur in all types of chemistry and microbiology laboratories . Because of the relative inexperience with the emerging technology of gene therapy, however, including possible vector replication or recombination, further vigilance in monitoring the safety of their applications is required. Todays Surg Nurse, 1996 Jul-Aug, 18(4), 27 - 9 Choosing the best protective gloves; Rosenblatt E; Gloves should provide two-way protection from the transmission of microorganisms between worker and patient . Until recently, glove manufacturers paid little attention to barrier properties . Because the operating room is a high-risk area, surgical nurses must be especially careful about gloving practices. Appl Microbiol Biotechnol, 1996 Jul, 45(6), 723 - 9 Safe biotechnology . 7 . Classification of microorganisms on the basis of hazard . Working Party "Safety in Biotechnology" of the European Federation Biotechnology; Lelieveld HL et al.; The current systems for classifying human pathogens on the basis of hazard are well developed and their basic criteria are in general agreement one with another . Of more importance, the safety practices based on these classifications have generally been successful . They have enabled extensive research activities, medical practice and industrial production to be conducted on an ever-increasing scale, involving dangerous microorganisms (e.g . in vaccine production and treatment of infected patients) with a very low incidence of adverse effects on the workers involved and the general public . Although the EU has adopted a harmonised list of agents in groups 1-4 there is as yet no complete agreement among member states and individual microbiologists . The purpose of this paper is to present a historical survey and to discuss the current processes for identifying and classifying the hazards posed by the use of microorganisms in research and technology . This is essential in the design of appropriate methods of counteracting potential risks. Genetika, 1996 Jul, 32(7), 922 - 6 {Mutator genes from Saccharomyces cerevisiae . Repair of artificial heteroduplexes in him and hsm mutants}; Gracheva LM et al.; During recent years, genes controlling mutation in higher eukaryotes have been found to be involved actively in carcinoma regeneration in cells . In this respect, studying the genetic control of mutagenesis becomes a key direction of research into mechanisms responsible for cancer generation . The results of studying interaction of mutations in the HSM3 and HSM6 genes, controlling spontaneous and induced mutagenesis in yeasts, and mutations impairing three known pathways of DNA damage repair in this microorganism, are described in this work . It was shown that mutation rev3 completely blocks UV-induced mutagenesis in all mutants studied . On the other hand, mutation rad2 synergistically interacts with mutations him1, hsm1, hsm3, hsm6, and hsm2, thus enhancing the frequency of UV-induced mutagenesis in double mutants multiple times . Mutations him2 and him3 manifested epistatic interaction with mutation rad2 . With mutation rad54, the interaction was epistatic for mutations him1 and hsm2 and was additive for mutations hsm1, him2, and him3 . On the basis of the data obtained, we developed a scheme for the appearance of mismatch bases in the process of repair of UV-induced DNA damage. Z Rheumatol, 1996 Jul-Aug, 55(4), 249 - 55 {Ankylosing spondylitis and urogenital infection: diagnosis of urologic infection and correlation with rheumatologic findings}; Lange U et al.; We examined 134 male patients with confirmed ankylosing spondylitis . The study protocol included a medical-rheumatological examination and thorough exploration for infections of the urinogential tract . An urethroadnexitis was found in 37 of 134 patients (27.6%): Two patients suffered from balanitis, 17 patients from urethritis, 18 patients from prostatitis, and two patients from epididymitis . Only four patients gave a history of urethritis and eight patients of prostatitis . The microorganisms isolated most frequently from patients with urogenital infection were Chlamydia trachomatis and, in few cases, Ureaplasma urealyticum . By comparing the urethroadnexitis group and the non-infected group with regard to other clinical parameters, we found a significantly increased C-reactive protein in the infected group . Other clinical parameters like involvement of the free spinal column, inflammatory involvement of the joints, and HLA-B27 correlation did not differ significantly. Lijec Vjesn, 1996 Jul-Aug, 118(7-8), 171 - 7 {Inhibition of bacterial adherence--possibilities of prevention and therapy}; Vranes J; The majority of bacterial infections begin with the adherence of pathogenic bacteria to the surfaces of epithelial cells . Microorganisms adhere to cells in a highly selective manner so that sneezing, coughing, peristalsis, and fluid flow cannot remove them . Even though the study of bacterial adherence gives a new insight: to the pathogenesis of infectious diseases, the question that always arises is whether infection can be prevented or treated by interfering with this first step in the pathogenesis of infectious diseases . Adherence may be inhibited by substances that block the interaction between the bacterial adhesin and the target cell receptor . These include the soluble form of receptor, antibodies against the receptor or against the adhesin, and antibiotics which impair bacterial adherence . In this review all three possibilities are considered. An Med Interna, 1996 Jul, 13(7), 347 - 52 {Superantigens: concept and applications in the pathogenesis and treatment of infectious and autoimmune diseases}; Quiros E et al.; The aim of this study was to review the characteristics of conventional antigens and the way they work, as well as to remark their differences with superantigens . They bind exclusively to the lymphocytic TCR V beta portion, are not processed by macrophages, are related to dependent HLA but not restrained HLA and are able to stimulate a hugh number of lymphocytes, leading them to destruction . Different microorganisms (toxins from S . aureus, S . pyogenes, M . arthritidis, etc . produce a high number of superantigens, which have been associated with infectious diseases, especially by HIV . They have also been related to immunological disorders such as multiple sclerosis, diabetes mellitus, Siogren's syndrome, sarcoidosis, etc . In conclusion, these new molecules will enable us to review the etiology of many diseases and, the most relevant from a clinical point of view, its treatment. Acta Otorrinolaringol Esp, 1996 Jul-Aug, 47(4), 314 - 6 {Acute otitis media caused by Nocardia asteroides}; Salvo Gonzalo S et al.; Nocardia asteroides is a bacteria that is distributed widely in nature and produces infection in most organs . Pulmonary nocardiosis is the most common form of clinical presentation . Few references exist regarding ear disease produced by this microorganism . A case of acute otitis media caused by N . asteroides produced subtotal tympanic perforation in a 45-year-old immunocompetent patient . The causal diagnosis was made by pure culture growth, repeated isolation and visualization of the microorganism in Gram-stained specimens of ear exudate . The strain was resistant to cotrimoxazole, but the patient was treated successfully with ciprofloxacin. J Endod, 1996 Jul, 22(7), 352 - 5 Effect of protoporphyrin IX limitation on porphyromonas gingivalis; Schifferle RE et al.; Porphyromonas gingivalis has been shown to require hemin or hemoglobin for in vitro growth . We have previously shown that protoporphyrin IX and inorganic iron can replace the hemin requirement, suggesting that the hemin requirement of this microorganism is actually a porphyrin requirement . We examined the effect of protoporphyrin IX limitation to P . gingivalis strain A7A1-28 in the presence of sufficient iron on growth characteristics, proteolytic enzyme production, virulence in a mouse abscess model, and expression of membrane proteins . Bacterial cells were grown in medium varying between 0 to 5 microM reduced growth by at least 50% . Protoporphyrin IX availability did not affect proteolytic enzyme production or virulence in a mouse abscess model . Sodium dodecyl sulfate-polyacrylamide gel electrophoresis of membrane preparations demonstrated that protoporphyrin IX limitation induced the expression of new proteins at 42, 34, 30, 29, and 18 kDa and suppressed the production of proteins at 47, 27, 17, and 15 kDa . These studies suggest that in vivo protoporphyrin availability may modulate membrane protein expression and in turn affect host immune responses against P . gingivalis. Rev Invest Clin, 1996 Jul-Aug, 48(4), 261 - 5 Helicobacter pylori and lymphoid follicles in primary gastric MALT-lymphoma in Mexico; Herrera-Goepfert R et al.; We reviewed our cases of gastric MALT-lymphomas over a 12-year period at a national oncological referral center, the Instituto Nacional de Cancerologia in Mexico City, looking for morphological evidence of Helicobacter pylori infection near the primary neoplasia . H pylori as well as lymphoid follicles and chronic active gastritis were carefully searched for in the adjacent mucosa . There were 23 (85%) low-grade and four (15%) high-grade MALT-lymphomas . H pylori microorganisms were found adjacent to the neoplasia in 23 cases (85%; CI 95% = 72-99%) but the lymphoid follicles were seen in 15 of 23 (65%; CI = 56-74%) . Chronic active gastritis was present in 25 cases (93%; Cl = 90-95%) . There was a close association between H pylori and gastric MALT-lymphoma . Lymphoid follicles were a reliable indicator of infection and the claimed pathophysiological substrate for MALT-lymphoma . We conclude that patients in whom gastric lymphoid follicles are detected, must remain under clinical follow-up since H pylori is a plausible promoter of neoplastic transformation. Mol Microbiol, 1996 Jul, 21(2), 293 - 300 A stringently controlled expression system for analysing lateral gene transfer between bacteria; Jaenecke S et al.; The lateral transfer of genetic information among microorganisms is a major force driving the outstanding adaptability of microbial communities to environmental changes . Until now little information has been obtained on gene transfer in natural ecosystems . We present here a genetic circuit for detecting and quantifying horizontal gene transfer from a defined donor microorganism to recipient organisms in the absence of selection for a recipient-specific phenotype . The system consists of an engineered lacZ (encoding beta-galactosidase) reporter gene whose expression is controlled by a synthetic regulatory element based on a fusion between the Pr promoter-operator from lambda bacteriophage and the 5' non-coding leader region of the inp gene encoding the IS 10 transposase function . Expression of this reporter cassette in the recombinant microorganism is completely shut down by two chromosomally encoded trans-acting repressors working at the level of transcription (the Cl-EK117 protein from the lambda phage), and at the level of translation (the antisense RNA-OUT of the IS 10 element) . When the reporter element is transferred to a different host by any mechanism, it escapes repression and becomes expressed . The system was validated with Pseudo-monas putida, and conjugational transfer frequencies of the reporter element as low as 10(-6) were detected . The modular design and broad host range of the genetic circuit, in combination with biomarkers which permit real-time in situ detection, will facilitate the monitor-ing of gene flow in a non-disruptive manner within the environment. Int J Food Microbiol, 1996 Jul, 30(3), 315 - 24 Genetically modified starter and protective cultures; Geisen R et al.; Modern approaches towards starter and protective culture improvement rely on advances in molecular biology . For most microorganisms used for food production, gene technological methods have been well developed . By recombinant DNA technology, 'tailor-made' starter and protective cultures may be constructed so as to combine technically desirable features . A single strain which normally would fail to accomplish a given 'task' may now be improved so as to meet a set of requirements necessary for a specific production or preservation process (e.g . wholesomeness, no off-flavour production, overproduction of bacteriocins or particular enzymes) . In addition, undesirable properties (e.g . mycotoxin or antibiotic production by cheese moulds) may be eliminated by techniques such as 'gene disruption'. Antonie Van Leeuwenhoek, 1996 Jul, 70(1), 1 - 10 DNA in soil: adsorption, genetic transformation, molecular evolution and genetic microchip; Trevors JT; This review examines interactions between DNA and soil with an emphasis on the persistence and stability of DNA in soil . The role of DNA in genetic transformation in soil microorganisms will also be discussed . In addition, a postulated mechanism for stabilization and elongation/assembly of primitive genetic material and the role of soil particles, salt concentrations, temperature cycling and crystal formation is examined. Dent Clin North Am, 1996 Jul, 40(3), 611 - 47 Pharmacologic management of the patient with disorders of the cardiovascular system . Infective endocarditis; Cowper TR; IE, although an infrequent event, remains a serious and frequently lethal complication in patients at risk . Oral microorganisms undoubtedly play a significant role in the development of IE in such patients . For example, in a retrospective review of prosthetic cardiac valve candidates (156) at the Cleveland Clinic Foundation, 15% were found to have at least one abscessed tooth, whereas approximately 17% were found to have severe (class IV) periodontal disease . Cardiac defects in conjunction with bacteremias from such dental pathoses clearly elevate the risk, although a small but increasing number of noncardiac conditions and behavioral patterns seem also to be able to induce susceptibility . Whether dental or other medical procedures are truly direct inducers of IE, however, remains to be proven and in all probability are only minor contributors overall . Despite its ubiquitous use, antibiotic prophylaxis has not been proven in human clinical trials, and its underlying rationale is arbitrary and questionable at best; nevertheless, its efficacy in animal models has led to the current human protocols . A more profitable strategy, and certainly an adjunctive one, should be to direct one's effort at eliminating oral pathology and educating and motivating patients at risk toward meticulous oral hygiene--an exhortation published many years before the advent of antibiotics and still undoubtedly the best recommendation today. Vet Microbiol, 1996 Jul, 51(1-2), 179 - 85 Improved method for preparation of samples for the polymerase chain reaction for detection of Coxiella burnetii in milk using immunomagnetic separation; Muramatsu Y et al.; Immunomagnetic separation (IMS) improved the detection of Coxiella burnetii in cow's milk by the polymerase chain reaction (PCR) . IMS represents a novel approach to the isolation of microorganism from milk . The combination of IMS and PCR analysis has an adequate sensitivity for detection of C . burnetii. Vet Microbiol, 1996 Jul, 51(1-2), 85 - 93 The sensitizing effect of a Brucella abortus antigen in cattle after repeated intradermal inoculations; Bercovich Z et al.; An antigen prepared from a mucoid strain of B . abortus was repeatedly injected intradermally into cattle to determine whether it sensitizes cattle so that they test false positive with the skin delayed-type hypersensitivity (SDTH) test . Cattle (n = 14) that were experimentally inoculated . with microorganisms that serologically cross-react with B . abortus, and uninfected cattle (n = 15) were tested with the antigen 2 to 5 times over a period of 16 to 17 weeks . An increase in skinfold thickness of > or = 2.0 mm on the injection site was considered a reaction elicited by the antigen . The sera from the cattle were tested with the serum agglutination test, complement fixation test, and an enzyme-linked immunosorbent assay for antibodies against B . abortus . Results showed that none of the animals had an increase in skinfold thickness of > or = 2.0 mm on the injection site of the antigen, which is considered a positive reaction . However, cattle experimentally inoculated with microorganisms other than B . abortus tested seropositive for brucellosis after one SDHT test only . We conclude that the B . abortus antigen inoculated intradermally does not sensitize cattle after repeated inculations, and therefore does not interfere with the subsequent use of the SDTH test in the diagnosis of brucellosis. Adv Ren Replace Ther, 1996 Jul, 3(3), 232 - 6 Peritonitis in peritoneal dialysis patients: an overview; Tzamaloukas AH; The incidence of peritonitis in peritoneal dialysis (PD) patients has decreased as a result of improvements in PD technology . Nevertheless, peritonitis remains a major problem in PD, with a substantial percent of patients developing persistent or relapsing infections . Current treatment guidelines emphasize the use of intraperitoneal antibiotics and once-a-day administration of aminoglycosides and provide indications for removal of the peritoneal catheter . Further clinical studies testing these guidelines are needed . In addition, guidelines for patients on PD treatment modalities other than standard continuous ambulatory peritoneal dialysis (CAPD) need to be developed . Peritonitis may lead to extensive adhesion formation, peritoneal fibrosis of varying severity, permanent loss of peritoneal ultrafiltration, severe malnutrition, sepsis, and death . Special forms of peritonitis requiring great care and further study include those caused by fungi, mycobacteria, and multiple microorganisms, and those developing in HIV-positive PD patients. Clin Infect Dis, 1996 Jul, 23(1), 101 - 6 Detection of a vacuolating cytotoxin in stools from children with diarrhea; Luzzi I et al.; A cytotoxin inducing vacuolation in HEp-2 cells was detected in 19 (3.1%) of 618 stool specimens from children with diarrhea but in none of 135 from control children . Common enteric pathogens were found in only two (10.5%) of the 19 cytotoxin-positive stool specimens . The vacuoles induced by stool filtrates resembled those induced by the vacuolating toxin (VacA) of Helicobacter pylori . The vacuolating toxin was heat-labile and protease-sensitive, and it had an apparent molecular weight of > 100,000 but was not neutralized by an antiserum to H . pylori VacA . Although proper prospective case-control studies are needed to definitely assess the etiologic association between the new vacuolating cytotoxin and diarrhea, the present study suggests that microorganisms of the gastrointestinal tract produce a Helicobacter-like vacuolating toxin and may be responsible for cases of childhood diarrhea whose etiology is currently considered unknown. J Prosthet Dent, 1996 Jul, 76(1), 8 - 14 Dimensional stability of seven elastomeric impression materials immersed in disinfectants; Thouati A et al.; Dental impressions can increase the transmission of microorganisms and infections . The purpose of this study was to assess the influence of three disinfectant solutions on the dimensional accuracy of seven elastomeric impression materials . Impressions of a test block were either left untreated (controls) or treated by immersion in a disinfectant solution . Measurements were taken on die stone replicas of the impressions . Comparisons were made between (1) the measurements for the variations in the nontreated impressions and those for the treated impressions and (2) measurements for the treated impressions and the test block . Results indicated that the aminoamphoteric agent or glutaraldehyde derivative-based solutions created little change in relation to the initial dimensional accuracy of the impression products . However, the sodium hypochlorite solution often leads to expansion by comparison with controls . By comparison to the test block, this expansion then makes it possible in most cases to obtain better dimensional accuracy than initially . Within the limits of this study this expansion could lead to an improvement in clinical fixed prosthodontic procedures. Nihon Kyobu Shikkan Gakkai Zasshi, 1996 Jul, 34(7), 804 - 9 {Allergic bronchopulmonary mycosis caused by Schizophyllum commune}; Tomita K et al.; In December 1989, a 72-year-old woman was hospitalized with atelectasis in the left lower lobe . The atelectasis resolved after bronchoscopic removal of impacted mucous plugs . Histopathological examination showed pulmonary mycosis . Microscopy suggested that a species of Aspergillus was responsible, but no definite diagnosis was made . After treatment with flucytosine and nebulized amphotericin, the patient's condition improved and she was discharged . In the middle of August 1994, she visited a local hospital complaining of fatigue . Eosinophilia (22%) was detected, and a few days later she visited that hospital again due to sudden dyspnea . A chest X-ray examination showed an abnormal shadow, and she was referred to our hospital . Atelectasis was seen in the left upper lobe . This finding, together with eosinophilia, suggested recurrence of pulmonary mycosis, and therefore bronchoscopy was performed . White mucous plugs obstructing the left upper lobe were observed and were bronchoscopically removed . Microscopical examination of the mucous plugs showed marked eosinophil infiltration and hyphae . Cultures of specimens obtained during bronchoscopy showed Schizophyllum commune, and allergic bronchopulmonary mycosis due to this microorganism was diagnosed . Identification of this microorganism as a cause of deep-seated pulmonary mycosis is very rare. Neurochem Int, 1996 Jul, 29(1), 83 - 7 Inhibition of cytokine-inducible nitric oxide synthase in rat microglia and murine macrophages by methyl-2,5-dihydroxycinnamate; Zielasek J et al.; Microglial cells are resident macrophages in the central nervous system (CNS) which serve specific functions in the defence of the CNS against microorganisms, the removal of tissue debris in neurodegenerative diseases or during normal development, and in autoimmune inflammatory disorders of the brain . Microglia express a cytokine-inducible isoform of nitric oxide synthase, which leads to the production of nitric oxide (NO) . Since NO is highly toxic to neurons and oligodendrocytes, we were interested to test down-regulating neuropeptides and second messenger de-activators in order to identify novel antagonists of cytokine-induced NO production . We found that only the tyrosine kinase inhibitor methyl-2,5-dihydroxycinnamate suppressed cytokine-induced NO production by rat microglial cells and murine macrophages, while a range of other tyrosine kinase inhibitors, neuropeptides and growth factors was ineffective . Since NO production may play a role in the pathogenesis of experimental neuro-immunological disorders like experimental autoimmune encephalomyelitis and experimental autoimmune neuritis, our findings suggest a possible therapeutic role for tyrosine kinase inhibitors. Kansenshogaku Zasshi, 1996 Jul, 70(7), 710 - 6 {Development of a detection system for Helicobacter pylori DNA in gastric juice}; Tamatsukuri S et al.; A rapid and sensitive PCR-based microwell plate assay (PCR-MWP) system to detect the 16 S ribosome RNA gene of Helicobacter pylori was developed . Analytical sensitivity, evaluated with purified recombinant plasmid DNA and genomic DNA of H . pylori, was one copy of DNA per PCR . Specificity was validated with a panel of DNA from 75 kinds of microorganisms including Helicobacter showed weak positives, when 1 pg of DNA was input . Other microorganisms gave negative signals even when 100 pg of DNA was used for PCR . When compared with a Nested-PCR system to detect the urease A-subunit gene performed by a commercial reference laboratory, the results obtained (sensitivity 93.3% and specificity 73.3%) was almost equivalent . The PCR-MWP was rapid and easy for the detection of H . pylori DNA in gastric juice specimen. Eur J Cancer B Oral Oncol, 1996 Jul, 32B(4), 264 - 70 Human papillomavirus in oral premalignant lesions; Nielsen H et al.; The aetiology of oral premalignant lesions is generally accepted to be multifactorial . Tobacco and alcohol are established as important cofactors in malignant development in the oral cavity, but in addition microorganisms, such as human papillomavirus (HPV), have gained much interest over the past decade . For many years, HPV has been accepted as an important cofactor in the development of cervical cancer, originating from a mucous membrane with similarities to the oral mucosa . 49 patients with oral premalignant lesions and 20 control patients with normal oral mucosa and no history of HPV infection were examined for the presence of HPV by immune histochemical staining using the peroxidase anti-peroxidase technique (PAP), DNA-DNA in situ hybridisation (ISH), and polymerase chain reaction (PCR) analysed by Southern blot hybridisation with an HPV 16 specific probe . The investigations revealed that HPV was found in 62.5% of the verrucous leucoplakias, 50.0% of the erythroplakias, 45.5% of the homogeneous leucoplakias, 33.3% of erythroleucoplakias and in 12.5% of the nodular leucoplakias . An overall HPV detection rate in the examined premalignant lesions was 40.8% and no patients in the control sample were positive . Concerning oral cancer development, it seems likely that HPV may be a cofactor, as 100% of patients who developed oral cancers within 4-12 years were all positive for HPV, one being positive for HPV 16. Trends Genet, 1996 Jul, 12(7), 263 - 70 The yeast genome project: what did we learn? Dujon B. The bakers' yeast, Saccharomyces cerevisiae, a microorganism of major importance for bioindustries, and one of the favored model organisms for basic biological research, is the first eukaryote whose genome is entirely sequenced . Beyond the wealth of novel biological information, it is the extent of what remains to be understood in the genome of a simple unicellular organism that is the most striking result: a significant proportion of yeast genes are orphans of unpredictable function . Offering the possibility of large-scale reverse genetics, yeast will be a powerful model for post-sequencing studies . But geneticists are now faced with the difficulty of asking novel questions. Kyobu Geka, 1996 Jul, 49(8 Suppl), 630 - 5 {Clinical problems in surgical treatment for active infective endocarditis}; Emmoto T et al.; From October, 1982, to December, 1995, 22 patients with active infective endocarditis underwent surgical treatment . Of 22 patients, 12 patients (group P) demonstrated microorganisms on blood culture obtained at the operation and/or in the excised valve, and 10 patients (group N) showed acute inflammatory reaction in the excised valve microscopically . Operative mortality in group P was significantly higher than that in group N (50% versus 0%,p < 0.01) . Especially in group P, five of six patients (83%) with uncontorolled infection for more than eight days died within 30 days of operation . This showed that prolonged preoperative periods of uncontrolled infection influenced the surgical outcome of active infective endocarditis . In conclusion, patients who do not promptly response to antibiotic treatment must be considered for early operation within seven days of the diagnosis of infective endocarditis to decrease operative mortality . The plasma level of CRP and definition of sepsis may be useful as indicators of uncontrolled infection. Infect Immun, 1996 Jul, 64(7), 2649 - 56 The major surface glycoprotein of Trypanosoma cruzi amastigotes are ligands of the human serum mannose-binding protein; Kahn SJ et al.; Trypanosoma cruzi, an obligate intracellular protozoan parasite, chronically infects mammals and causes Chagas' disease in humans . T . cruzi evasion of the mammalian immune response and establishment of chronic infection are poorly understood . During T . cruzi infection, amastigotes and trypomastigotes disseminate in the mammalian host and invade multiple cell types . Parasite surface carbohydrates and mammalian lectins have been implicated in the invasion of mammalian cells . A recent study has demonstrated that the human mannose-binding protein and the macrophage mannose receptor, two mammalian C-type lectins, bind to T . cruzi (S . J . Kahn, M . Wleklinski, A . Aruffo, A . Farr, D . Coder, and M . Kahn, J . Exp . Med . 182:1243-1258,1995) . In this report we identify the major surface glycoproteins, including the SA85-1 glycoproteins, as T . cruzi ligands of the mannose-binding protein . Further characterization of the interaction between the mannose-binding protein and T . cruzi demonstrates that (i) the SA85-1 glycoproteins are expressed by amastigotes and trypomastigotes but only amastigotes express the mannose-binding protein ligand, (ii) treatment of amastigotes with alpha-mannosidase inhibits the binding of mannose-binding protein, and (iii) amastigote binding of mannose-binding protein is stable despite the spontaneous shedding of some glycoproteins from its surface . Together, the data indicate that developmentally regulated glycosylation of surface glycoproteins controls the expression of ligands that affect the interactions between T . cruzi and mannose-binding protein . It has been established that the binding of mannose-binding protein to microorganisms facilitates their uptake into phagocytic cells . Preferential opsonization of amastigotes with mannose-binding proteins may account for their clearance from the circulation and may contribute to the parasite's ability to invade different cell types. Infect Immun, 1996 Jul, 64(7), 2391 - 9 Ability of Escherichia coli isolates that cause meningitis in newborns to invade epithelial and endothelial cells; Meier C et al.; Escherichia coli isolates that cause meningitis in newborns are able to invade the circulation and subsequently cross the blood-brain barrier . One mechanism for traversing the blood-brain barrier might involve transcytosis through the endothelial cells . The ability of the meningitis isolate E . coli IHE3034, of serotype 018:K1:H7, to invade epithelial (T24) and endothelial (EA-hy926) cells was investigated by the standard gentamicin survival assay and by electron microscopy . Human bladder epithelial and endothelial cells were efficiently invaded by strain IHE3034, whereas epithelial human colon Caco-2 cells, canine kidney MDCK cells, and the opossum {correction of opposum} epithelial kidney cell line OK were not invaded . The ability to invade human epithelial cells of the bladder could also be demonstrated for several other newborn meningitis E . coli strains and one septicemic E . coli strain . Studies utilizing inhibitors which act on eukaryotic cells revealed a dependence on microfilaments as well as on microtubules in the process of E . coli IHE3034 entry into T24 and EA-hy926 cells . These results indicated that cell cytoskeletal rearrangements are involved in bacterial uptake and suggest that there are either two pathways (microtubule dependent and microfilament dependent) or one complex pathway involving both microtubules and microfilaments . The intracellular IHE3034 organisms were contained in a host-membrane-confined compartment mainly as single microorganisms . Intracellular replication of 1HE3034 was not detected, nor did the number of intracellular bacteria decrease significantly during a 48-h period . The ability of E . coli O18:K1 to invade and survive within certain eukaryotic cells may be another virulence factor of meningitis-associated E . coli. Gastroenterology, 1996 Jul, 111(1), 19 - 27 Association between Helicobacter and gastric ulcer disease of the pars esophagea in swine; Queiroz DM et al.; BACKGROUND & AIMS: Swine present spontaneously peptic ulcer in the gastric pars esophagea and are frequently colonized by a spiral bacterium that is of the same species as Helicobacter heilmannii type 1 . This organism is also observed in the gastric mucosa of patients with gastric symptoms and who present with gastritis at histology . The aim of this study was to investigate the association between the presence of H . heilmannii type 1 and lesions of the pars esophagea . METHODS: H . heilmannii type 1 infection was investigated by mouse inoculation, urease test, and carbolfuchsin stain in 20 stomachs with ulcer, 30 stomachs with preulcer lesions, and 20 stomachs with a macroscopically normal pars esophagea . RESULTS: The microorganism was more frequently found in the stomachs with ulcer (100%) and in those with preulcer lesions (90%) than in stomachs with macroscopically normal pars esophagea (35%) . Histological alterations were observed in the pars esophagea and in the glandular regions of bacterium-positive stomachs . CONCLUSIONS: It has been shown that the microorganism is strongly associated with naturally occurring ulcer and preulcer lesions of the pars esophagea of swine, which raises the possibility that the bacterium is an important factor in the pathogenesis of these lesions. Am J Respir Crit Care Med, 1996 Jul, 154(1), 91 - 7 Effect of ventilator-associated pneumonia on mortality and morbidity; Papazian L et al.; The aim of this study was to evaluate the attributable mortality and excess intensive care unit (ICU) stay as linked to ventilator-associated pneumonia (VAP) in a medical-surgical ICU . We performed a matched cohort study . The diagnosis of VAP was established when clinical, biologic, and radiologic signs of VAP were associated with the presence of at least one microorganism at a concentration > or = 10(3) CFU/ml on the protected specimen brush sample . Each case patient with VAP was matched to one control patient on the basis of the following potential confounding factors: same diagnosis and same indication for mechanical ventilation, same age +/-5 yr, same sex, same APACHE II score +/-5 on admission . In addition, control patients had to be ventilated for at least as long as the case patient prior to the onset of VAP, and date of admission of the case and control patients had to be matched within 1 yr . In 85 of the 97 patients with VAP, we were able to match one case patient with one control patient . Mortality was similar in both case (40%) and control (38.8%) patients . The duration of mechanical ventilation was increased in survivor case patients (27.2 +/- 24.7 d) compared with survivor control patients (18.5 +/- 15.7 d) (p < 0.01) . The duration of hospitalization in ICU was increased in survivor case patients (34.9 +/- 23.6 d) compared with survivor control patients (26.1 +/- 18.6 d) (p < 0.02) . When confounding factors were controlled, VAP did not appear to increase mortality. Microb Ecol, 1996 Jul, 32(1), 59 - 71 Relationship Between Abundance of N2-fixing Cyanobacteria and Environmental Features of Spanish Rice Fields Quesada A, Valiente EF. In order to estimate the potential utilization of N2-fixing (heterocystous) cyanobacteria as natural biofertilizers in the Valencian rice fields (Spain), the distribution and seasonal variation of these microorganisms in water and sediment samples were evaluated, and the relationships among cyanobacterial abundance and physical and chemical characteristics of soil and water were investigated . N2-fixing cyanobacteria were present in all the samples analyzed (25 sampling points sampled three times per year during two years) . The relative cyanobacterial abundance in soil and water followed contrasting patterns, maximum presence in soil coincided with minimum abundance in water . Correlation analysis showed that cyanobacterial abundance in the two phases (water and sediment) was influenced more by water than by soil properties . Salinity,mineralization variables, and soluble reactive phosphate (SRP) correlated positively with heterocystous cyanobacteria presence . Furthermore, dissolved inorganic nitrogen (DIN) and the ratio DIN:SRP correlated negatively with cyanobacterial abundance . However DIN:SRP ratio better described the cyanobacterial distribution, with a threshold effect: below the Redfield ratio value (7.2 in mass units) cyanobacterial abundance was clearly higher. Proc Natl Acad Sci U S A, 1996 Jun 25, 93(13), 6626 - 30 A human axillary odorant is carried by apolipoprotein D; Zeng C et al.; The characterization of the source of the odor in the human axillary region is not only of commercial interest but is also important biologically because axillary extracts can alter the length and timing of the female menstrual cycle . In males, the most abundant odor component is known to be E-3-methyl-2-hexenoic acid (E-3M2H), which is liberated from nonodorous apocrine secretions by axillary microorganisms . Recently, it was found that in the apocrine gland secretions, 3M2H is carried to the skin surface bound to two proteins, apocrine secretion odor-binding proteins 1 and 2 (ASOB1 and ASOB2) with apparent molecular masses of 45 kDa and 26 kDa, respectively . To better understand the formation of axillary odors and the structural relationship between 3M2H and its carrier protein, the amino acid sequence and glycosylation pattern of ASOB2 were determined by mass spectrometry . The ASOB2 protein was identified as apolipoprotein D (apoD), a known member of the alpha2mu-microglobulin superfamily of carrier proteins also known as lipocalins . The pattern of glycosylation for axillary apoD differs from that reported for plasma apoD, suggesting different sites of expression for the two glycoproteins . In situ hybridization of an oligonucleotide probe against apoD mRNA with axillary tissue demonstrates that the message for synthesis of this protein is specific to the apocrine glands . These results suggest a remarkable similarity between human axillary secretions and nonhuman mammalian odor sources, where lipocalins have been shown to carry the odoriferous signals used in pheromonal communication. Proc Natl Acad Sci U S A, 1996 Jun 25, 93(13), 6241 - 6 A psychrophilic crenarchaeon inhabits a marine sponge: Cenarchaeum symbiosum gen . nov., sp . nov; Preston CM et al.; Archaea, one of the three major domains of extant life, was thought to comprise predominantly microorganisms that inhabit extreme environments, inhospitable to most Eucarya and Bacteria . However, molecular phylogenetic surveys of native microbial assemblages are beginning to indicate that the evolutionary and physiological diversity of Archaea is far greater than previously supposed . We report here the discovery and preliminary characterization of a marine archaeon that inhabits the tissues of a temperate water sponge . The association was specific, with a single crenarchaeal phylotype inhabiting a single sponge host species . To our knowledge, this partnership represents the first described symbiosis involving Crenarchaeota . The symbiotic archaeon grows well at temperatures of 10 degrees C, over 60 degrees C below the growth temperature optimum of any cultivated species of Crenarchaeota . Archaea have been generally characterized as microorganisms that inhabit relatively circumscribed niches, largely high-temperature anaerobic environments . In contrast, data from molecular phylogenetic surveys, including this report, suggest that some crenarchaeotes have diversified considerably and are found in a wide variety of lifestyles and habitats . We present here the identification and initial description of Cenarchaeum symbiosum gen . nov., sp . nov., a symbiotic archaeon closely related to other nonthermophilic crenarchaeotes that inhabit diverse marine and terrestrial environments. J Immunol Methods, 1996 Jun 21, 193(2), 149 - 56 Assessment of in vivo attachment/phagocytosis by alveolar macrophages; Weaver T et al.; Alveolar macrophages (AMs) are recognized as an important first line of cellular host defense within the lung . Although mechanisms underlying AM response to microorganisms or particulates are well characterized in vitro, experimental approaches to the study of AMs in vivo are limited . To circumvent these limitations, a new assay was developed using fluorescently labelled liposomes or Pneumocystis carinii (PC) organisms which were administered intratracheally into mechanically ventilated rats . After 30 min, the lungs were lavaged and the percentage of administered liposomes or PC bound to AMs was determined by quantifying fluorescence . Factors known to enhance attachment/phagocytosis by AMs in vitro were assayed to determine their effect in vivo . For example, vitronectin (VN)-coated liposomes increased attachment from 25.2 +/- 2.4% to 47.2 +/- 3.0% (p < 0.001), while addition of VN increased the binding of PC to AMs from 16.5 +/- 1.7% to 24.5 +/- 2.2% (p < 0.05) . Confocal laser microscopy of cells obtained by lavage provided morphologic evidence of attachment/phagocytosis by AMs . This model will permit the quantitative assessment of the interaction of fluorescently labelled liposomes or microorganisms with AMs in the lower respiratory tract of living animals. J Cell Biochem, 1996 Jun 15, 61(4), 562 - 8 Carbohydrate-carbohydrate interactions in adhesion; Spillmann D et al.; Cell-cell interactions play an important role in the development, maintenance, and pathogenesis of tissues . They are highly dynamic processes which include migration, recognition, signaling, adhesion, and finally attachment . Cells on their pathway to a final location have to pass and interact with their substratum formed of matrix and cell layers . Testing and recognition are important keys for the proper result of tissue formation . They can, however, also lead to diseases when they are misused in pathological situations, by microorganisms or malignant cells, for instance . Carbohydrates, which are the most prominent surface-exposed structures, must play an important role as recognition molecules in such processes . The rich variability of carbohydrate sequences which cell surfaces can present to lectins, adhesion molecules, and other ligands creates a refined pattern of potential attachment sites . The subtle control of the surface presentation density can provide variations in attachment strength . Not only the carbohydrate sequences but also the fact that carbohydrates can be branched while proteins cannot and that the oligosaccharide chains can be attached to the protein backbone in different densities and patterns will create yet more interaction possibilities . Maximal use of the combinatorial richness of carbohydrate molecules would be made when carbohydrate sequences could interact with other carbohydrate sequences . Such interactions have only very rarely been considered for biochemically and biologically relevant situations since they are difficult to measure . A few are known and will be summarized here with the hope that this wealth of possible chemical interactions may be considered more and more by surface cell biochemists when analyzing fine tuning in cellular interactions. Clin Lab Sci, 1996 Jul-Aug, 9(4), 207 - 12 The laboratory diagnosis of tuberculosis in a period of resurgence: challenge for the laboratory; Amsterdam D; OBJECTIVE: To review the current and contemporary approaches to the laboratory diagnosis of Mycobacterium tuberculosis and related mycobacteria . DATA SOURCES: Current literature . STUDY SELECTION: Determined by the author . DATA EXTRACTION: Determined by the author . DATA SYNTHESIS: The definitive diagnosis of mycobacterial disease depends upon the laboratory for the isolation and identification of the infecting microorganism . Laboratory studies encompass microscopic examination for the presence of AFB; isolation and recovery of the organism by cultural methods; phenotypic biochemical or other contemporary means to identify the recovered organism; and anti-tuberculosis susceptibility testing . Because of the extended growth period of this group of organisms, it is imperative that the lab use the most rapid means to provide information to the clinician for isolation of the patient if needed and for the initiation of prompt rational therapy as determined by susceptibility testing . More than 25 species in the Mycobacterium genus are capable of causing human disease . In the United States, the five most frequently encountered species are M . tuberculosis, M . avium, M . kansasii, M . fortuitum and M . chelonei . CONCLUSION: Tuberculosis is a reemerging disease with significant health problem implications in the US and worldwide . Diagnosis and appropriate treatment are dependent on the prompt response of the laboratory. J Ind Microbiol, 1996 Jun, 16(6), 360 - 3 Genes, enzymes and secondary metabolites in industrial microorganisms . The 1995 Thom Award Lecture; Beppu T; Apparently contrasting approaches, ie genetic engineering and screening of new microorganisms, play essential complementary roles to develop current industrial microbiology . Three topics, production and modification of milk-clotting proteinases by genetic engineering, hormonal control of secondary metabolism in streptomycetes, and screening of bioactive metabolites, are introduced as cases of such a hybrid approach, while symbiotic microorganisms are discussed as an example of the vast terra incognita still remaining for the future microbiology. Arq Neuropsiquiatr, 1996 Jun, 54(2), 324 - 7 {Cerebral malaria and AIDS: case report}; Hinrichsen SL et al.; Although it has not been definitely proven that the severity of malaria is associated to human immunodeficiency virus (HIV) we know that infection through Plasmodium falciparum can favor a rapid evolution of the HIV infection . Besides, association of malaria with HIV/AIDS from a clinical point of view can be clinically severe in the face of the occurrence of other microorganisms or neoplasias, which worsens the evolution and prognosis of the affected patients . The concurrence of HIV with Plasmodium in malaria endemic zones is a possibility which should always be taken into consideration, since transmission is related to risk factors caused by people's behavior which are not always promptly revealed and/or identified . The authors report one case of brain malaria infection by Plasmodium vivax and Plasmodium falciparum in a patient with AIDS . They describe the clinical evolution and therapy. Ceska Gynekol, 1996 Jun, 61(3), 144 - 7 {Infectious agents and treatment of infertility with IVF and ET}; Dostal J et al.; An infectious agent is a confirmed etiological factor of female tubal sterility . In conjunction with the recorded decline of fertility of the male population the participation of infection in this trend can be taken into consideration . In the submitted paper the authors are concerned with the detection of an infectious agent in spermatozoa in the sterile population and its role when using assisted reproduction techniques (ART) . From the results ensues that cultivation examinations of spermatozoa before a programme of in vitro fertilization and embryo transfer (IVF + ET) has its place in the screening of the treated couple . Detection of virulent types of microorganisms has a negative effect on results of IVF + ET . Groups of men with this finding should be treated with antibiotics with regard to sensitivity and at the same time cultivation examinations of their partners should be made an necessary treatment and provided. Rev Sci Tech, 1996 Jun, 15(2), 409 - 22 Importation of aquaculture seedlings to Japan; Wakabayashi H; Japan is one of the largest consumers of fishery products in the world . Importation of various fishery commodities - including larvae and eggs for aquaculture - is increasing due to high consumer demand . Elvers of Anguilla anguilla have been imported from Europe since the late 1960s . Eyed eggs of coho salmon (Oncorhynchus kisutch) are imported from North America . During the last decade, over-production caused the price of Japanese amberjack (or 'yellowtail') (Seriola quinqueradiata) and Japanese seabream (Pagrus major) to drop, forcing farmers to venture into the culture of other species . A variety of marine fish seedlings are now imported from Asian countries . Almost all aquaculture production of coho salmon, greater amberjack (Seriola dumerili), seabass (Lateolabrax japonicus), rockfish (Sebastes spp.) and groupers (Epinephlus septemfaciatus, etc.) depends on imported seedlings . These species accounted for approximately 9% by value of marine finfish production in Japan in 1993 . Apart from ubiquitous or endemic pathogens, a considerable number of exotic microorganisms and parasites are suspected to have accompanied fish eggs and larvae imported for aquaculture purposes . On a voluntary basis, 80-90% of imported salmon eggs are being examined for bacterial kidney disease and salmon viruses by semi-governmental organisation . Voluntary inspections are also being conducted on some other fish species imported from foreign countries . No legislation exists, however, for the control of exotic fish pathogens. Int J Food Microbiol, 1996 Jun, 30(1-2), 113 - 23 Sensitive populations: who is at the greatest risk? Gerba CP, Rose JB, Haas CN. The purpose of this article was to review the existing literature to define those groups of individuals who would be at the greatest risk of serious illness and mortality from water and foodborne enteric microorganisms . This group was found to include the very young, the elderly, pregnant women, and the immunocompromised . This segment of the population currently represents almost 20% of the population in the United States and is expected to increase significantly by the beginning of the next century, because of increases in life-span and the number of immunocompromised individuals . More than half of documented deaths from gastroenteritis and hepatitis A illness occur in the elderly in developed countries . The overall case fatality ratio for foodborne bacterial gastroenteritis outbreaks in nursing homes is 10 times greater than the general population . Pregnant mothers suffer from a case fatality ratio from hepatitis E infections ten times greater than the general population during waterborne disease outbreaks . Enteric diseases are most common and devastating among the immunocompromised . Cryptosporidium is a serious problem among patients with acquired immuno-deficiency syndrome (AIDS) . Cancer patients undergoing chemotherapy and transplant patients, are also at significantly greater risk of dying from enteric viral infections than the general population . This review indicates the need for consideration of enhanced protection for certain segments of the population who will suffer the most from food and waterborne pathogens. Eur J Oral Sci, 1996 Jun, 104(3), 322 - 4 Elevated cortisol levels in whole saliva in HIV infected individuals; Enwonwu CO et al.; Free cortisol concentrations in unstimulated whole saliva samples, collected at 10.00 to 11.00 h, from 23 unmedicated HIV-positive patients and 14 control subjects were measured by radioimmunoassay . Mean cortisol level (nmol/l +/- SD) was significantly higher in the HIV patients than in control subjects (27.4 +/0 9.3 vs . 10.1 +/- 3.5) . Two HIV patients with pseudomembranous candidiasis had the highest saliva cortisol concentrations (mean of 48.5 nmol/l) . Two other HIV patients (one with Kaposi's sarcoma and the other with periodontitis) had a mean cortisol value of 29.9 nmol/l . The possibility of plasma contamination of whole saliva in the HIV patients with inflammatory oral mucosal lesions notwithstanding, our findings suggest an increased oral burden of cortisol in both the asymptomatic and symptomatic HIV-infected individuals . Glucocorticoids caused immunosuppression, provide selective growth advantage to various microorganisms including the fungi, and enhance replication or reactivation of latent viruses (e.g . EBV, CMV, Kaposi's sarcoma-associated herpes viruses) . Our findings suggest a need to evaluate the relevance of endogenous glucocorticoid excess in blood and saliva to the causation of some major AIDS-associated oral lesions such as candidiasis, Kaposi's sarcoma, oral hairy leukoplakia and necrotizing gingivitis. Curr Opin Obstet Gynecol, 1996 Jun, 8(3), 211 - 5 Contraception in the 1990s; Shoupe D; Contraceptive technology has recently provided the market place with new barrier methods, new progestin oral contraceptives, an injectable contraceptive, the female condom, new male condoms, and the contraceptive implant . During the last decade, epidemiologists have clearly defined the non-contraceptive benefits of current contraceptive methods that include decreased infections, protection from various cancers, protection from many gynecologic problems that lead to surgery, as well as symptomatic relief from many gynecologic conditions . In conjunction with medical specialists, contraceptive researchers have established the increased safety and benefits of various contraceptive choices in women with medical conditions that, until recently, were contra-indications for their use . That these advances have occurred despite multiple legal and scientific assaults gives hope that the field will continue to growPIP: In the face of legal challenges and adverse scientific publications that threaten the acceptance of various methods of contraception, this article reviews the forms of contraception currently available in the US and assesses their safety, efficacy, and medical benefits . Information is provided on 1) male and female condoms, which offer protection from pregnancy and from sexually transmitted diseases; 2) the spermicide Nonoxynol-9, which kills harmful microorganisms but is toxic to vaginal epithelium; 3) the contraceptive sponge; 4) the diaphragm (used with spermicides) and cervical cap; 5) Norplant, which is associated with troublesome side effects but still scores 78% satisfaction ratings; 6) Depo-Provera, which has been associated with bone loss; and 7) IUDs, which were used by 10% of women in the 1970s but are used by less than 2% today . The bulk of the report is devoted to oral contraceptives (OCs), which are described as "one of the most thoroughly studied pharmacological agents of the 20th century." The risks associated with OC use are reviewed, as are such topics as failure rates, mechanism of action, side effects, beneficial effects, effects of use on cancer rates, safety for breast-feeding women, contraindications, and the risk of venous thromboembolism associated in recent studies with formulations containing third-generation progestins . It is concluded that the development of contraceptive technology is being guided by a new emphasis on protecting health while preventing pregnancy . Pharmacol Rev, 1996 Jun, 48(2), 289 - 326 Toxicology and pharmacology of the chemical warfare agent sulfur mustard; Dacre JC et al.; There have been reports of chemical attacks in which sulfur mustard might have been used (a) on Iranian soldiers and civilians during the Gulf War in 1984 and 1985 and (b) in an Iraqi chemical attack on the Iranian-occupied village of Halbja in 1988, resulting in many civilian casualties . Heavy use of chemical warfare in Afghanistan by the Soviet military is a recent innovation in military tactics that has been highly successful and may ensure further use of chemical agents in future military conflicts and terrorist attacks as a profitable adjunct to conventional military arms . Mustard is a poisonous chemical agent that exerts a local action on the eyes, skin, and respiratory tissue, with subsequent systemic action on the nervous, cardiac, and digestive systems in humans and laboratory animals, causing lacrimation, malaise, anorexia, salivation, respiratory distress, vomiting, hyperexcitability, and cardiac distress . Under extreme circumstances, dependent upon the dose and length of exposure to the agent, necrosis of the skin and mucous membranes of the respiratory system, bronchitis, bronchopneumonia, intestinal lesions, hemoconcentration, leucopenia, convulsions with systemic distress, and death occur . Severe mustard poisoning in humans is associated with systemic injury, which is manifested as headache, epigastric distresses, anorexia, diarrhea, and cachexia and is usually observed at mustard doses of 1000 mg/min/m3 with damage to hematopoietic tissues and progressive leucopenia . Sulfur mustard is a cell poison that causes disruption and impairment of a variety of cellular activities that are dependent upon a very specific integral relationship . These cytotoxic effects are manifested in widespread metabolic disturbances whose variable characteristics are observed in enzymatic deficiencies, vesicant action, abnormal mitotic activity and cell division, bone marrow disruption, disturbances in hematopoietic activity, and systemic poisoning . Indeed, mustard gas readily combines with various components of the cell such as amino acids, amines, and proteins . Although evidence of an association between lung cancer and mustard gas encountered on the battlefields of World War I is at best suggestive if not problematical (Case and Lea, 1955; Beebe, 1960; Norman, 1975), the epidemiological data accumulated from the poison gas factories in Japan (Yamada et al., 1953; Wada et al., 1968; Inada et al., 1978; Shigenobu, 1980; Nishimoto et al., 1983; Hirono et al., 1984; Takuoka et al., 1986), in Germany (Weiss, 1958; Hellmann, 1970a; Weiss and Weiss, 1975; Klehr, 1984) and in England (Manning et al., 1981; Easton et al., 1988) are substantial (International Agency for Research on Cancer, 1975) . Unfortunately, attempts to seek confirmatory and substantial evidence in laboratory animals such as mice (Boyland and Horning, 1949; Heston, 1950; Heston, 1953a; McNamara et al., 1975) and rats (Griffin et al., 1951; McNamara et al., 1975; Sasser et al., 1996) have not been consistent . Sulfur mustard has been shown to be mutagenic in a variety of different species using many different laboratory techniques from fruit flies, microorganisms and mammalian cell cultures (Fox and Scott, 1980) . Evidence is slowly accumulating from human data (Hellmann, 1970a; Lohs, 1975; Wulf et al., 1985) . Evidence for the teratogenicity of mustard has been negative in assessment of fetotoxicity and adverse effects of mustard on the reproductive potential of both human and animal studies . Indeed, investigations of women adversely affected by mustard are minimal because most of the studies have been performed on former men employees of poison gas factories and have been negative or questionable . We have recently emphasized the need to assess the affect of a suspected teratogen on maternal toxicity in laboratory animals before any conclusions can be made.(ABSTRACT TRUNCATED) Appl Environ Microbiol, 1996 Jun, 62(6), 1913 - 21 Ribulose-1,5-bisphosphate carboxylase/oxygenase gene expression and diversity of Lake Erie planktonic microorganisms; Xu HH et al.; Carbon dioxide fixation is carried out primarily through the Calvin-Benson-Bassham reductive pentose phosphate cycle, in which ribulose-1, 5-bisphosphate carboxylase/oxygenase (RubisCO) is the key enzyme . The primary structure of the large subunit of form I RubisCO is well conserved; however, four distinct types, A, B, C, and D, may be distinguished, with types A and B and types C and D more closely related to one another . To better understand the environmental regulation of RubisCO in Lake Erie phytoplanktonic microorganisms, we have isolated total RNA and DNA from four Lake Erie sampling sites . Probes prepared from RubisCO large-subunit genes (rbcL) of the freshwater cyanobacterium Synechococcus sp . strain PCC6301 (representative of type IB) and the diatom Cylindrotheca sp . strain N1 (representative of type ID) were hybridized to the isolated RNA and DNA . To quantitate rbcL gene expression for each sample, the amount of gene expression per gene dose (i.e., the amount of mRNA divided by the amount of target DNA) was determined . With a limited number of sampling sites, it appeared that type ID (diatom) rbcL gene expression per gene dose decreased as the sampling sites shifted toward open water . By contrast, a similar trend was not observed for cyanobacterial (type IB) rbcL gene expression per gene dose . Complementary DNA specific for rbcL was synthesized from Lake Erie RNA samples and used as a template for PCR amplification of portions of various rbcL genes . Thus far, a total of 21 clones of rbcL genes derived from mRNA have been obtained and completely sequenced from the Ballast Island site . For surface water samples, deduced amino acid sequences of five of six clones appeared to be representative of green algae . In contrast, six of nine sequenced rbcL clones from 10-m-deep samples were of chromophytic and rhodophytic lineages . At 5 m deep, the active CO2-fixing planktonic organisms represented a diverse group, including organisms related to Chlorella ellipsoidea, Cylindrotheca sp . strain N1, and Olisthodiscus luteus . Although many more samplings at diverse sites must be accomplished, the discovery of distinctly different sequences of rbcL mRNA at different water depths suggests that there is a stratification of active CO2-fixing organisms in western Lake Erie. Curr Opin Biotechnol, 1996 Jun, 7(3), 321 - 5 Co-metabolism: is the emperor wearing any clothes? Wackett LP. Co-metabolism is a term used for biochemically undefined observations in catabolic enzyme substrate specificity, the interplay between enzyme specificity and metabolic regulation, the metabolic interdependence of microorganisms, and co-substrate requirements in the catabolism of xenobiotic compounds . Recent findings in these four areas of microbial biochemistry necessitate a re-evaluation of the widespread use of the term. Clin Infect Dis, 1996 Jun, 22(6), 1096 - 8 Lymphocyte subset counts during the course of community-acquired pneumonia: evolution according to age, human immunodeficiency virus status, and etiologic microorganisms; Fantin B et al.; We investigated the evolution of lymphocyte subsets in blood samples from 94 consecutive patients with community-acquired pneumonia; these samples were obtained 72 hours after hospitalization and at follow-up, when the patients were considered to be cured . Acute-phase lymphocyte counts, as compared with follow-up counts, were decreased in the overall population (P < .0001); however, the percentage of CD4+ T cells remained unchanged during the course of pneumonia in each patient . These changes that were noted for the overall population were not significantly influenced by age, the presence (or not) of infection with human immunodeficiency virus (HIV), or etiologic microorganisms . Of the 68 HIV-seronegative patients, 12 had initial CD4+ T cell counts of < 200/mm3; multivariate analysis revealed that this finding was significantly associated with the presence of an underlying disease or tuberculosis and an age of > or = 60 years. Clin Perinatol, 1996 Jun, 23(2), 287 - 304 Neonatal gastrointestinal mucosal immunity; Mannick E et al.; The gastrointestinal mucosal immune system is a complex system with multiple interacting cells, which express different markers and elaborate a variety of mediators in response to noxious stimuli and pathogens . At birth this system is quite immature, putting the newborn mammal at risk for a variety of infectious and noninfectious diseases . With age and antigenic stimulation, maturation occurs and intestinal host defense then functions quite effectively to protect the host from ingested noxious substances and microorganisms. Microbiologia, 1996 Jun, 12(2), 207 - 18 Molecular basis of Brucella pathogenicity: an update; Sangari FJ et al.; Microorganisms belonging to the genus Brucella can infect humans and many species of animals . Virulence of the brucellae is thought to be essentially due to their capacity to survive and replicate within the phagocytic cells . However, many gaps remain in our understanding of this ability of brucellae to elude the bactericidal effects of host phagocytes, and basic questions remain unanswered . Identification of Brucella gene products which are related to intracellular survival, as well as those which contribute to the induction of protective immunity, is critical to elucidate the molecular mechanisms of the pathogenesis of the organism . The present article summarizes the current status of the research on gene products and other structural or metabolic factors associated with virulence of the brucellae. Monaldi Arch Chest Dis, 1996 Jun, 51(3), 188 - 93 Changes of serum concentration of lipid peroxidation products in patients with pneumonia; Nowak D et al.; During lower respiratory tract infection, massive influx and activation of phagocytes is observed . Reactive oxygen species (ROS) released by macrophages and polymorphonuclear neutrophils (PMNs) kill microorganisms and cause damage to host tissues . One feature of this damage may be enhanced lipid peroxidation . Therefore, the aim of this study was to estimate the serum concentration of lipid peroxidation products in combination with clinical and biochemical indicators of inflammation in 32 patients with pneumonia . Serum concentration of lipid peroxides (CLP) and malondialdehyde (CMDA) was measured at Day 1, 4, 10 and 14 of observation, whilst chest radiography and routine blood analysis were performed at Day 1 and 14 during a 2 week treatment of lower airway infection . The CLP decreased during treatment (p < 0.05) from 0.059 +/- 0.024 to 0.043 +/- 0.017 (A532 nm) and the CMDA (p < 0.05) from 3.5 +/- 1.4 to 2.8 +/- 1.3 nmol.mL-1 . A negative correlation between CLP and radiological regression (r = 0.49) and a drop in white blood cell count (WBC) (r = 0.39) was observed during the treatment . A positive correlation between CMDA and serum trypsin inhibitory capacity (STIC) (r = 0.47) and erythrocyte sedimentation rate (ESR) (r = 0.43) was found . Our data indicate that an enhanced process of lipid peroxidation occurs during pneumonia and that serum concentration of lipid peroxides returns to normal values quicker than the concentration of malondialdehyde during recovery . The use of antioxidants is suggested as an adjuvant treatment in patients with pneumonia. Parasite, 1996 Jun, 3(2), 183 - 5 Madin Darby canine kidney: a new cell line for Pneumocystis carinii in vitro culture; Atzori C et al.; Pneumocystis carinii pneumonia (PCP) is a highly frequent cause of morbidity and mortality in immunocompromised subjects, particularly in HIV-infected ones . The biology of P . Carinii is poorly understood because of the lack of reliable synthetic media or adequate cell lines to grow this opportunistic pathogen in continuous culture . We reported the suitability of the MDCK (Madin Darby Canine Kidney, ATTC CCL 34) cell line to support the temporary microorganism's growth in vitro and the experimental pharmacological trials, in comparison with the HEL 299 cell line, used as reference standard. Dermatol Nurs, 1996 Jun, 8(3), 160 - 4 The value and limitations of protective gloves in medical health service: Part I; Mellstrom GA et al.; The value of protective gloves in the health care environment is well known . However, these gloves are not perfect . Some are permeable to microorganisms and various chemicals, and/or result in side effects for health care professionals . Gloves that offer the greatest protection and least side effects are highly desirable . Field of application rules and regulations, materials and manufacturing, and test methods of protective gloves are described in Part I of this three part series. Int J Lepr Other Mycobact Dis, 1996 Jun, 64(2), 152 - 8 Evolution of lymphocyte populations in armadillos (Dasypus novemcinctus) inoculated with M . leprae; Guerra-Infante F et al.; In human leprosy patients there are changes in the percentages of T and B lymphocytes in peripheral blood, and there is a correlation with the clinical characteristics or manifestations of the disease . These phenomena still require clarification regarding the triggering mechanism involved that may lead to one or the other clinical entities . Much has yet to be learned about the intricacies of whether the changes in subpopulations of T and B lymphocytes are a causative factor or an effect attributable to the microorganism itself . The armadillo is an excellent animal model to study how Mycobacterium leprae spread, turning into an established infection . The application of modifications in percentages of the subpopulations of B and T lymphocytes in armadillos may well lead to extrapolation of the results obtained in this animal model in an attempt to be able to manipulate the course of the disease in humans . The purpose of the study was to evaluate changes in the percentages of rosette-forming and sIgM+ mononuclear cells during a full year in groups of armadillos: five randomly chosen animals formed the control group and 11 armadillos were inoculated with M . leprae obtained from a human leproma at the onset of the 12-month period of the study . Of the 11 randomly selected armadillos that were inoculated, only five developed an active and disseminated infection . The percentage of rosette-forming cells did not show statistically significant variations during the first 6 months of the study . However, at months 8 and 12 a significant increment in this parameter was observed (p < 0.05) in the animals with active infection . In regard to the variations in the numbers of sIgM+ cells, significant changes occurred in the armadillos with active infection at month 2 . However, results returned to normal and no changes were seen at later times . No significant changes occurred in the group of animals inoculated but not developing active infection compared with the other groups . The results are considered sufficiently interesting to encourage further study on the cell-mediated immune system of the armadillo and the changes that occur during the development and dissemination of an inoculated infection with M . leprae . Since this mammal is of great value as an effective animal model in the experimental research of M . leprae, there is an urgent need to obtain, as quickly as possible, a thorough understanding of the cellular branch of its immune system and, thereby, be in a position to extrapolate immune modulation to benefit human leprosy patients. Crit Care Med, 1996 Jun, 24(6), 1072 - 8 Sepsis/septic shock: participation of the microcirculation: an abbreviated review; Hinshaw LB; OBJECTIVE: An overview of the importance of understanding mechanisms occurring in the microcirculation during septic and endotoxic shock . The thesis of the paper is to place emphasis on this important vascular network to ultimately benefit the patient . DATA SOURCES: Early descriptions of vascular reactions to endotoxin which suggest that the microcirculation is a major site of attack during shock . More recent studies were sought out and examined as to their possible impacts on the microcirculation . STUDY SELECTION: Early comprehensive studies concerning vascular reactions in the microcirculation during shock were selected . Subsequent studies identified from the mainstream scientific medical literature describe the actions of blood, cells, and the emerging significant role of the vascular endothelium among other factors . A consensus view is identified, pointing to the causes of a malfunctioning microcirculation during shock . DATA EXTRACTION: Data gathered from reports in the mainstream, well-established basic and clinical literature, from reviews and forum reports, from studies by well-established investigators, and from more recent reports of excellent quality . DATA SYNTHESIS: The microcirculation undergoes massive alterations during sepsis/septic shock . There are numerous changes, including slowing of capillary blood flow due to depressed perfusion pressure as a result of systemic pressure reduction and local arteriolar constriction . Observations suggest that the microcirculation is shut off early in severe sepsis, allowing the effects of hypoperfusion and attacks by microorganisms to prevail in their destructive capabilities . Widespread capillary dilation may ultimately occur . However, with blood flow diverted through some arteriovenous channels, important areas of capillary exchange are bypassed . Decreased capillary blood flow during shock results from failure to allow normal passage of cellular elements, including erythrocytes and neutrophils . This defect occurs, in part, because of decreased perfusion pressure, decreased deformability of red and white cells, constricted arterioles, circulating obstructive fragments (including hemoglobin), and plugging of microvessels with "sludge." Other factors are adherence of cells to capillary and venular epithelial membranes creating increased resistance to flow, loss of fluid through abnormal transcapillary exchange, differential vascular resistance changes between various beds (e.g., intestinal vs . muscle), and the relative absence of regulatory neurohumoral control of small vessel segments of the circulation . During sepsis/septic shock, endothelial cells are reported to modulate vascular tone, control local blood flow, influence the rate of leakage of fluids and plasma proteins into tissues, modulate the accumulation and extravasation of white cells into tissues, and influence white cell activation . As a result of the predominance of many destructive factors, a subsequent round of tissue damage may occur . Because of prolonged capillary vascular stasis, deficient flow, and factors released from injured cells, the microcirculation becomes a trap for uncontrolled bacterial growth enhanced by sustained hypoxemia, acidosis and toxemia . These events may combine to contribute to the loss of normal cell integrity and death of the host . CONCLUSIONS: The purpose of this review is to draw the readers' attention to the growing list of adverse factors occurring in the microcirculation during sepsis/septic shock . A further aim is to point to the realization of the complexity of factors which may contribute to the importance of a well-functioning microcirculation. J Immunol, 1996 Jun 1, 156(11), 4377 - 83 Characterization and subcellular localization of target membrane soluble NSF attachment protein receptors (t-SNAREs) in macrophages . Syntaxins 2, 3, and 4 are present on phagosomal membranes; Hackam DJ et al.; Phagosomes formed during ingestion of microorganisms by leukocytes undergo a rapid maturation, generating an acidic, microbicidal organelle . Maturation requires interactions with intracellular vesicles that dock and fuse preferentially with the phagosomal membrane . The basis of specificity of vesiculo-phagosomal interaction has not been elucidated . By contrast, the molecular basis of vesicular fusion in other systems is better understood . At neural synapses, vesicular docking and fusion to the plasma membrane are mediated by a protein complex including syntaxin 1 . We explored whether macrophages contain syntaxins, and whether selective fusion of vesicles with the phagosome results from the accumulation of syntaxins in the phagosomal membrane . Isoform-specific Abs were utilized to demonstrate utilized to demonstrate that syntaxins 2, 3, and 4, but not syntaxin 1, are present in murine and human macrophages . Biochemical characterization demonstrated the presence of these syntaxins on microsomes, where they are integral membrane proteins . Subcellular localization using confocal immunofluorescence microscopy demonstrated that syntaxins 3 and 4 are present on the plasma membrane as well as on intracellular vesicles . Importantly, phagosomes isolated by fractionation were shown by immunoblotting to contain syntaxins 2, 3, and 4, suggesting that they may participate in phagosomal maturation . The density of the syntaxins on the phagosomal membrane was found to be comparable with that on the surface membrane . This suggests that preferential fusion of vesicles with the phagosomal membrane is not the result of segregation of the syntaxins to this organelle . Instead, local generation of second messengers in the vicinity of the phagosomal membrane may trigger focal fusion. Trends Biotechnol, 1996 Jun, 14(6), 190 - 7 Identifying microbial diversity in the natural environment: a molecular phylogenetic approach; Hugenholtz P et al.; Our knowledge of microbial biodiversity has been severely limited by relying on microorganisms that have been cultured; these represent only a tiny fraction of the microbial diversity in the environment . Recently, however, recombinant DNA and molecular phylogenetic techniques have provided methods for characterizing natural microbial communities without the need to cultivate organisms . These techniques have allowed a glimpse of the complexity of microbial communities and the huge, largely untapped, biotechnological resource that they represent. J Bacteriol, 1996 Jun, 178(11), 2999 - 3007 Cold shock and cold acclimation proteins in the psychrotrophic bacterium Arthrobacter globiformis SI55; Berger F et al.; The psychrotrophic bacterium Arthrobacter globiformis SI55 was grown at 4 and 25 degrees C, and the cell protein contents were analyzed by two-dimensional electrophoresis . Cells subjected to cold shocks of increasing magnitude were also analyzed . Correspondence analysis of protein appearance distinguished four groups of physiological significance . Group I contained cold shock proteins (Csps) overexpressed only after a large temperature downshift . Group II contained Csps with optimal expression after mild shocks . Group III contained proteins overexpressed after all cold shocks . These last proteins were also overexpressed in cells growing at 4 degrees C and were considered to be early cold acclimation proteins (Caps) . Group IV contained proteins which were present at high concentrations only in 4 degrees C steady-state cells and appeared to be late Caps . A portion of a gene very similar to the Escherichia coli cspA gene (encoding protein CS7.4) was identified . A synthetic peptide was used to produce an antibody which detected a CS7.4-like protein (A9) by immunoblotting two-dimensional electrophoresis gels of A . globiformis SI55 total proteins . Unlike mesophilic microorganisms, this CS7.4-like protein was still produced during prolonged growth at low temperature, and it might have a particular adaptive function needed for balanced growth under harsh conditions . However, A9 was induced at high temperature by chloramphenicol, suggesting that CS7.4-like proteins have a more general role than their sole implication in cold acclimation processes. Surgery, 1996 Jun, 119(6), 694 - 700 Hypothesis: compartmentalization of cytokines in intraabdominal infection; Schein M et al.; BACKGROUND . Although the proximal role of systemic cytokines in the infectious-inflammatory cascades is well recognized, the magnitude and meaning of its intraperitoneal levels in peritonitis have received little attention . We hypothesized that in peritonitis a significant and clinically relevant cytokine-mediated inflammatory response is compartmentalized in the peritoneal cavity . METHODS . MEDLINE was used to search the literature for all articles dealing with experimental, primary, and secondary bacterial peritonitis and cytokines . RESULTS . Bacterial peritonitis is associated with an immense intraperitoneally compartmentalized cytokine response, with plasma levels of cytokines representing only the tip of the iceberg . Although certain amount of cytokines may be beneficial to the peritoneal defense mechanisms, higher levels correlate with adverse outcome . Thus it is plausible to look at acute peritonitis as initially a combined infective (microorganism) and inflammatory (cytokines) process . The clinical significance of the distinction between peritoneal inflammation and infection and the relevance of our findings to the stratification and treatment of peritonitis are discussed . CONCLUSIONS . Current surgical and antibiotic therapy for peritonitis is able to clear the peritoneal cavity of infective concentration of bacteria, but many patients continue to die of an uncontrolled activation of the inflammatory cascade . We suggest that one potential venue for therapeutic progress is the modulation of the compartmentalized peritoneal inflammatory response. Mol Pharmacol, 1996 Jun, 49(6), 956 - 61 A distinct G(i) protein-coupled receptor for sphingosylphosphorylcholine in human leukemia HL-60 cells and human neutrophils; Van Koppen CJ et al.; The sphingolipids, sphingosylphosphorylcholine (SPPC) and sphingosine-1-phosphate (SPP), induce a rapid and transient rise in intracellular free calcium concentration ({Ca2+}i) in a variety of cell lines via activation of pertussis toxin-sensitive G protein-coupled receptors . We investigated whether these sphingolipids act on different receptors by testing the effect of varying concentrations of SPPC on {Ca2+}i in human leukemia HL-60 cells, which have been found to be nonresponsive to SPP . SPPC potently (EC50 = 1.5 microM) and rapidly increased {Ca2+}i in HL-60 cells in a pertussis toxin-sensitive manner . Differentiation of HL-60 cells through treatment with dibutyryl cAMP into granulocyte-like cells did not change the magnitude or the pertussis toxin sensitivity of the SPPC-induced {Ca2+}i rise, indicating that the receptor for SPPC is constitutively expressed in HL-60 cells . SPPC did not activate phospholipase C or D in HL-60 cells . However, SPPC, but not SPP, stimulated the generation of superoxide anions in dibutyryl cAMP-differentiated HL-60 cells as well as in human neutrophils, suggesting that the SPPC receptor may play a role in the inflammatory defense against invading microorganisms . On the basis of these results, we conclude that there apparently is a heterogeneity of G protein-coupled receptors for sphingolipids in mammalian cells. J Thorac Cardiovasc Surg, 1996 Jun, 111(6), 1213 - 8 Perioperative microbiologic monitoring of tracheal aspirates as a predictor of pulmonary complications after cardiac operations; Zickman B et al.; The value of preoperative and early postoperative microbiologic testing of tracheal aspirates as a prognostic indicator of the development of pneumonia was evaluated in a prospective study of 213 cardiac surgical patients . Tracheal aspirates were obtained immediately after intubation and after the patient's arrival at the intensive care unit . Diagnosis of pneumonia was accepted if at least three of the following criteria were fulfilled: leukocytosis > 15,000 cells/mm3, body temperature >38.5 degrees C, positive results of auscultation, positive results of radiography (new infiltrates that seemed to be consistent with pneumonia), and increased core-reactive protein for more than 2 days after operation . Potentially pathogenic microorganisms were found in 54 (25.4%) of the preoperative tracheal aspirates and in 27 (12.7%) of the early postoperative tracheal aspirates . Positive microbiologic findings correlated with pneumonia in the postoperative course in 24.1% (p < 0.001) if the preoperative culture results were positive, in 48.2% (p < 0.001) if the postoperative culture results were positive, and in 44.0% (p < 0.001) if both were positive . The risk of pneumonia was increased in male patients (p < 0.05) and in patients with chronic obstructive pulmonary disease (p < 0.05) . Demographic variables, smoking, acute pulmonary symptoms, temperature, leukocyte count at the day of the operation, and data on the operation and the extracorporeal circulation were not significantly related to pneumonia in the early postoperative course . The risk of development of postoperative pneumonia is significantly higher among patients with colonization of the lower respiratory tract . Positive culture results in routine microbiologic monitoring of tracheal aspirates are predictive of pulmonary complications after cardiac operations. Eur J Biochem, 1996 May 15, 238(1), 121 - 8 Characterization of centrin genes in Paramecium; Madeddu L et al.; Centrins are highly conserved, ubiquitous cytoskeletal components which belong to the EF-hand superfamily of Ca2+-modulated proteins . We report here the molecular characterization of new members of the centrin family, Paramecium centrins . Previous studies described the organization of the infraciliary lattice (ICL), the innermost cortical cytoskeletal network of Paramecium, and showed that it was composed of a set of low-molecular-mass, Ca2+-binding polypeptides {Garreau de Loubresse, N., Klotz, C., Vigues, B., Rutin, J & Beisson, J . (1991) Biol . Cell 71, 217-225} . In this paper we show that these polypeptides are recognized by specific anti-centrin polyclonal antibodies . Their microsequences revealed four distinct N-termini . For one of them, ICL1, N-terminal and internal peptide sequences were used for PCR amplification and cloning of a DNA fragment containing a complete centrin coding sequence . The deduced amino acid sequence presents about 50% identify with those of centrins from other species . Further molecular analysis allowed us to identify two additional closely related, co-expressed ICL1 genes, providing the first example of a centrin multigenic family in a microorganism. Proc Natl Acad Sci U S A, 1996 May 14, 93(10), 4999 - 5002 Escherichia coli exhibits negative chemotaxis in gradients of hydrogen peroxide, hypochlorite, and N-chlorotaurine: products of the respiratory burst of phagocytic cells; Benov L et al.; Escherichia coli can respond to gradients of specific compounds, moving up gradients of attractants and down gradients of repellents . Stimulated phagocytic leukocytes produce H2O2, OCl-, and N-chlorotaurine in a response termed the respiratory burst . E . coli is actively repelled by these compounds . Catalase in the suspending medium eliminated the effect of H2O2 . Repulsion by H2O2 could be demonstrated with 1 microM H2O2, which is far below the level that caused overt toxicity . Strains with defects in the biosynthesis of glutathione or lacking hydroperoxidases I and II retained this response to H2O2, and 2.0 mM CN- did not interfere with it . Mutants with defects in any one of the four known methyl-accepting chemotaxis proteins also retained the ability to respond to H2O2, but a "gutted" mutant that was deleted for all four methyl-accepting chemotaxis proteins, as well as for CheA, CheW, CheR, CheB, CheY, and CheZ, did not respond to H2O2 . Hypochlorite and N-chlorotaurine were also strongly repellent . Chemotaxis down gradients of H2O2, OCl-, and N-chlorotaurine may contribute to the survival of commensal or pathogenic microorganisms. J Biol Chem, 1996 May 3, 271(18), 10704 - 8 Intrinsic activity and stability of bifunctional human UMP synthase and its two separate catalytic domains, orotate phosphoribosyltransferase and orotidine-5'-phosphate decarboxylase; Yablonski MJ et al.; Human UMP synthase is a bifunctional protein containing two separate catalytic domains, orotate phosphoribosyltransferase (EC 2.4.2.10) and orotidine-5'-phosphate decarboxylase (EC 4.1.1.23) . These studies address the question of why the last two reactions in pyrimidine nucleotide synthesis are catalyzed by a bifunctional enzyme in mammalian cells, but by two separate enzymes in microorganisms . From existing data on subunit associations of the respective enzymes and calculations showing the molar concentration of enzyme to be far lower in mammalian cells than in microorganisms, we hypothesize that the covalent union in UMP synthase stabilizes the domains containing the respective catalytic centers . Evidence supporting this hypothesis comes from studies of stability of enzyme activity in vitro, at physiological concentrations, of UMP synthase, the two isolated catalytic domains prepared by site-directed mutagenesis of UMP synthase, and the yeast ODCase . The two engineered domains have activities very similar to the native UMP synthase, but unlike the bifunctional protein, the domains are quite unstable under conditions promoting the dissociated monomer. FEMS Microbiol Lett, 1996 May 1, 138(2-3), 207 - 10 1-Aminocyclopropane-1-carboxylate deaminase genes from Pseudomonas strains; Campbell BG et al.; Microbial ACC deaminase catalyses the conversion of 1-aminocyclopropane-1-carboxylate (ACC), the precursor to the phytohormone ethylene, to ammonia and alpha-ketobutyrate . We screened microorganisms for ACC degrading ability and cloned and sequenced the ACC deaminase genes from two Pseudomonas strains which displayed high enzyme activity . One of the genes was homologous with two previously sequenced ACC deaminase genes, but the other was different. FEMS Microbiol Lett, 1996 May 1, 138(2-3), 167 - 72 Polymerase chain reaction and an outer membrane protein gene probe for the detection of Porphyromonas gingivalis; Hiratsuka K et al.; A sensitivity assay for Porphyromonas gingivalis based upon the polymerase chain reaction (PCR) was developed . A 426-bp sequence, including a DraI-HincII DNA fragment (278 bp) encoding the 40-kDa outer membrane protein of the P . gingivalis gene was amplified . PCR products were obtained from chromosomal DNAs of the P . gingivalis strains tested but not from those of other oral microorganisms . The lower limit of template DNA detection was 10 pg with 30 cycles and 100 fg with 40 cycles of PCR by agarose gel electrophoresis . The PCR products were hybridized with DraI-HincII DNA fragment internal to the PCR primers regions used . The lower limit of hybridization detection was 10 pg and 10 fg of template DNA with 30 and 40 cycles of PCR, respectively . These results demonstrated the simplicity, rapidity and specificity of the procedure, as well as the use of the DraI-HincII DNA fragment in the identification of P . gingivalis. Yakugaku Zasshi, 1996 May, 116(5), 374 - 87 {Induction of biological activities by chemically modified subfragments from human serum IgG and their application to development of medicine}; Mimura T; Immunoglobulin G (IgG) is an important protein in humoral immunity . After IgG binds to the specific foreign antigen, IgG-antigen complexes are eliminated either by making it easier for a phagocytic cell to ingest them or by activating a complement system . We found that the carboxyamidemethylated subfragments obtained from human serum IgG by reduction and alkylation of its interchain disulfide bonds, have anti-ulcerogenic, anti-inflammatory and anti-allergic activities, while no activity was recognized in the original IgG . On the other hand, some saturated and unsaturated fatty acids generally existing in microorganisms were found to have anti-inflammatory and anti-ulcerogenic activities . As the application of these researches, we synthesized hybrid compounds from sulfur-containing amines and fatty acids to make a lead compound for developing a new medicine . In this review, the experimental process will be discussed. Dig Dis, 1996 May-Jun, 14(3), 192 - 200 Enteric immunization: promises and challenges; Brown WR; Immunization to prevent many intestinal infections is inadequate because most available vaccines are given parenterally, a route that does not effectively stimulate the intestinal immune system . Thus, investigators are pursuing several strategies for achieving enteric protection through oral immunization . The most promising approaches are the incorporation of immunogens into microparticles for protection and enhanced uptake of the immunogen by intestinal lymphoid tissues, the genetic manipulation of microorganisms, and the use of mucosal adjuvants . The achievement of effective oral immunization against intestinal infections could lead to control of serious diarrheal illnesses, which still are a major worldwide health problem. Ann Nucl Med, 1996 May, 10(2), 185 - 91 FDG-PET in infectious lesions: The detection and assessment of lesion activity; Ichiya Y et al.; The usefulness of FDG-PET in the detection of infectious foci and the assessment of lesion activity was evaluated . The study covered 24 patients with 25 FDG-PET studies, including lesions of bacterial, tuberculous and fungal origins . The FDG uptake was determined by the lesion to muscle ratio (LMR) on the static images . The time activity curves (TACs) were classified into four patterns based on both the existence of an initial peak and a slope thereafter . A high FDG uptake was observed in 23 of 25 lesions (92%) . Two lesions, in which no abnormal uptake was noted, included one in the healing stage and the other consisting of a cavity with a thin wall . The acute active lesions showed higher LMRs than the chronic active or healing lesions (mean +/- SD: 9.8 +/- 3.6, 3.6 +/- 1.8 and 4.3 +/- 1.7, respectively, p < 0.05), and they could be approximately distinguished by an LMR of 6 . The patterns of the TACs in acute or chronic active lesions were either an increase without an initial peak or a plateau, while those in the healing lesions demonstrated predominantly an increase with an initial sharp peak . Our results indicated that FDG-PET is clinically useful in the detection of the infection of miscellaneous microorganisms as well as in the assessment of lesion activity. Arch Kriminol, 1996 May-Jun, 197(5-6), 165 - 74 {Cadaver lipid: various origins add to the difficulty of assessing postmortem time}; Rothschild MA et al.; Establishing the length of time since death is particularly difficult in corpses showing advanced putrefaction . One particular sign of advanced decay is the formation of adipocere, as observed mainly in drowned bodies or following a long period of storage under airtight conditions . During storage in an open, damp environment (e.g . water) the formation of adiopocere becomes visible after approximately 3-6 months and can be found in more extensive form after approximately one year . In this state bodies show evidence of a partly waxlike and partly pasty condition . Continued storage ultimately results, among other things, in further decomposition due to the action of microorganisms from the surrounding area-even if this is chronologically delayed . An exception is provided by the formation of adipocere under air-tight conditions (e.g . wrapped in plastic material or in mass graves) . Initially autolysis and heterolysis also occur, involving the release of fatty acids from the lipids produced naturally in the body . As a result of the subsequent hydrogenation of the fats by the action of bacterial enzymes, the unsaturated fatty acids are partially converted into saturated fatty acids . As the fatty acids released in large quantities during adipocere formation clearly have a bactericidal effect, further bacterial decomposition is stopped at this early adipocere stage . Additional microorganisms from outside can no longer infiltrate when this hermetic seal is in place . In addition, the lack of calcium (e.g . from water or moist earth) can be a reason for the fact that further adipocere development, leading to wax-like hardening of the fat, is arrested . The soft parts of the body retain a soft, viscous consistency . Thus the condition of the body can remain constantly preserved over many years and no longer allows a reliable estimate to be made of the period of time since death. New Horiz, 1996 May, 4(2), 289 - 99 Trauma, shock, and gut translocation; Deitch EA et al.; This article reviews the scientific and clinical evidence that supports trauma and shock as potential etiologies for translocation of intestinal microorganisms and their by-products . The potential for loss of intestinal barrier function to cause the eventual septic deaths observed in such patients, as well as possible mechanisms for preventing and treating this entity is also discussed. Zh Mikrobiol Epidemiol Immunobiol, 1996 May-Jun, (3), 110 - 4 {The use of a bioprofile of Escherichia for its epidemiological marking}; Liashenko IE et al.; The analysis of the penetrating and expressing capacity of the markers of bacterial persistence, adhesive capacity, antibiotic resistance and colicinogenicity in 254 E.coli strains of 7 groups, isolated from different ecotopes, including different environmental objects and bodies of healthy and sick children, revealed the specific character of their population bioprofiles, i.e . complexes of phenotypical signs of microorganisms . The results of the cluster analysis carried out with regard to the totality of data on E.coli bioprofiles made it possible to detect two clusters: the first cluster included pathogenic E.coli isolated from children with pathogenic processes, the second one included non-pathogenic E.coli isolated from healthy children and from aqueous objects . The levels of the information content of individual signs of microorganisms were determined and the use of E.coli bioprofiles for their epidemiological marking was substantiated. An Med Interna, 1996 May, 13(5), 235 - 8 {Applications of the polymerase chain reaction (PCR) to the diagnosis of central nervous system infections}; Querol JM et al.; The utility of polymerase chain reaction (PCR) is described for the diagnosis in three patients suffering from central nervous system infections, tuberculous meningitis, herpetic encephalitis and cerebral toxoplasmosis . PCR was performed in the cerebrospinal fluid after processing the specimen by two methods, proteinase K digestion and phenol extraction of DNA . Amplification was realized using primers previously described that amplify specific DNA fragments of each microorganisms (insertion sequence IS6110 of Mycobacterium tuberculosis, B1 gene of Toxoplasma gondii, and DNA polymerase gene of Herpes simplex virus) . In all three cases, PCR was positive after amplification of the specimen extracted with proteinase K, as well as when a complete DNA extraction with phenol was realized . In all cases a band of amplified products was observed in agarose gels . In conclusion, in all three patients described, PCR would had allowed the diagnosis in seven hours, and PCR should be consider a rapid sensitive and relatively simple method. J Vet Med Sci, 1996 May, 58(5), 473 - 6 Canine infectious cyclic thrombocytopenia found in Taiwan; Chang AC et al.; Here were report the first canine infectious cyclic thrombocytopenia (CICT) found in Taiwan . Platelet-specific inclusions were detected in the blood smear of a military working dog . To identify the etiologic agent, the patient's blood was transmitted to three six-month-old German Shepherd dogs . The Ehrlichia platys-like inclusions were observed six to eight days after inoculation . Indirect fluorescent antibody test showed that the serum from the patient reacted specifically with the microorganisms within the platelets . Typical hematologic manifestations of E . platys infection, cyclic parasitemia and concomitant thrombocytopenia, were observed in these dogs . The prevalence of CICT in north Taiwan was also studied, and the incidence was 8.9% (4 out of 45) in civilian dogs and 97.1% (34 out of 35) in dogs from a heavily tick infested kennel. Diagn Cytopathol, 1996 May, 14(3), 263 - 7 Fine-needle aspiration cytology of bronchocentric granulomatosis: a potential diagnostic pitfall; Mourad WA et al.; Bronchocentric granulomatosis (BCTG) is a rare disease associated with bronchial asthma and bronchopulmonary aspergillosis . Idiopathic forms are rarely encountered . We report on a case of BCTG showing clinical, radiological, and cytological evidence suggestive of adenocarcinoma of the lung . The patient is a 69-yr-old female, lifetime nonsmoker with multiple sclerosis who was admitted with a history of ascending cholangitis . Admission chest X-ray documented a 1.5-cm nodule in the left upper lobe of the lung . This was confirmed by CT scan . The lesion was slowly growing . Bronchoscopic examination was normal . Bronchial brushings were inconclusive . A transthoracic fine-needle aspiration showed sheets of highly atypical epithelium with occasional small dyshesive clusters . There was an inflammatory background that was believed to represent tumor diathesis . The cytological interpretation was "suspicious for adenocarcinoma." The patient underwent left upper lobectomy . The lung showed multiple peribronchial granulomas with intense peribronchial lymphoid infiltrate extending into the bronchial mucosa, causing cytological atypia and focal ulceration . Special stains for microorganisms were negative . The patient recovered from surgery and shows no signs of infection . We conclude that BCTG and related lesions can give cytological features that are suggestive of malignancy . Cytological material obtained from these lesions should be interpreted with caution. Anat Rec, 1996 May, 245(1), 102 - 13 Tonsils of the soft palate of young pigs: crypt structure and lymphoepithelium; Belz GT et al.; BACKGROUND: Tonsils of the soft palate are especially important in pigs as the major pharyngeal mucosal-associated lymphoid tissue and as a portal of entry for microorganisms . They play a key role in initiating immune responses against antigens entering tonsillar crypts from the oropharynx . The aim of this study was to describe the architecture of the tonsillar crypst and the morphology of their epithelial surface . METHODS: Tissue taken from the tonsil of the soft palate of freshly-killed pigs was examined using light microscopy, electron microscopy, and three-dimensional reconstruction techniques . RESULTS: Tonsils of the soft palate in pigs are penetrated by numerous crypts which extend into, and branch extensively within, the lymphoid tissue . Stratified squamous non-keratinised epithelium covering the oropharyngeal surface is continuous with that lining the neck of crypts . Lymphoepithelium covers the tonsillar lymphoid tissue within the crypts . It consists of non-keratinised epithelial cells, M cells, goblet cells and many intraepithelial lymphoid cells . M cells have a variable surface morphology: some are covered by relatively regular and well-formed microvilli; others possess very long undulant microvilli emanating from broad membranous folds . CONCLUSIONS: Variations in M cell surface morphology occur and these may reflect alterations of the apical plasmalemma in response to antigenic stimuli . Further investigation will be required to determine molecular specializations of the apical membrane of M cells which may facilitate interactions with antigenic material. J Clin Microbiol, 1996 May, 34(5), 1158 - 60 Bartonella (Rochalimaea) quintana infection in a seronegative hemodialyzed patient; Drancourt M et al.; Bartonella quintana is a reemerging pathogen responsible for trench fever, endocarditis, bacteremia, and bacillary angiomatosis . We previously reported the first case of a patient with B . quintana-induced chronic adenomegaly, and here we present a report on a second patient . A hemodialyzed patient with Sjogren's syndrome presented with mediastinal adenomegalies and secondary pancytopenia . All diagnostic investigations remained negative, except that a Bartonella-like microorganism was isolated from a bone marrow biopsy . The isolate was identified as B . quintana by a specific mouse polyclonal antibody and by determination of a partial gltA (citrate synthase-encoding) gene and 16S rRNA gene sequences . DNA of the pathogen was also detected in the adenomegaly and in the serum of the patient by PCR amplification of the gltA gene . Anti-B . quintana antibodies were never detected in the patient's serum throughout the 12-month follow-up but were detected in the serum of the patient's cat . The patient's outcome was favorable after treatment with gentamicin . Chronic adenomegaly in seronegative patients is a new clinical entity due to B . quintana. Ultrastruct Pathol, 1996 May-Jun, 20(3), 195 - 202 Cat scratch disease and acquired immunodeficiency disease: diagnosis by transmission electron microscopy; Guccion JG et al.; A 33-year-old, homosexual, cat-owning, African-American man with human immunodeficiency virus infection by positive serologic tests and acquired immunodeficiency syndrome by CD4 lymphocyte count alone (39 cells/mL) presented with a one-year history of intermittent fever, weight loss, and generalized lymphadenopathy . A malignant lymphoma was suspected clinically . Light microscopic study of a left inguinal lymph node biopsy specimen revealed effacement of the lymph node architecture by a diffuse infiltrate of large, atypical reticulum cells, loose, patchy granulomatous inflammation, diffuse hyaline fibrosis, diffusely proliferated blood vessels, and multifocal degeneration and necrosis . Lymph follicles were absent and lymphocytes were moderately depleted . Microorganisms were not seen in lymph node sections stained with special histochemical stains (including the Warthin-Starry stain) . These light microscopic changes were considered suggestive of a malignant lymphoma, especially Hodgkin's disease . The diagnosis of cat scratch disease (CSD) became apparent only after transmission electron microscopic study of the lymph node revealed clusters of small, pleomorphic bacteria in degenerated collagenous tissue and in blood vessel walls . This case illustrates the value of transmission electron microscopy in making the diagnosis of CSD, especially when light microscopic changes are superimposed on those of late human immunodeficiency virus infection of the lymph node. J Anim Sci, 1996 May, 74(5), 1134 - 43 Preservation of ruminal microorganisms for in vitro determination of ruminal protein degradation; Luchini ND et al.; Ruminal microorganisms, preserved either lyophilized or frozen, were compared with freshly strained ruminal fluid for proteolytic activity and as inoculum source for determination of ruminal protein degradation rates by the inhibitor in vitro method . Dialysis and glycerol addition had no effect on the proteolytic activity of preserved microorganisms . Net release of NH3 and total amino acids from protein using the fluid plus particle-associated microorganisms was higher than that found using the fluid-associated microorganisms alone . Method of inoculum preservation altered total proteolytic activity, but harvesting bacteria using centrifugal force greater than 5,000 x g did not increase proteolytic activity of the pellet . The proposed method for harvesting and preserving microorganisms consisted of centrifuging strained ruminal fluid at 5,000 x g (30 min at 4 degrees C), stirring the pellet in a 50:50 (vol/vol) solution of glycerol-McDougall's buffer for 15 min, and then storing at -20 degrees C . Protein degradation rates in incubations with preserved microorganisms were four to eight times slower than when using fresh ruminal fluid; however, feed proteins were ranked similarly for degradation rate . Preincubating the preserved microorganisms reduced blank concentrations of NH3 and total amino acid and increased protein degradative activity of the preserved inoculum . Degradation rates with preincubated, preserved inocula were similar to those obtained using fresh ruminal fluid . These results indicated that mixed ruminal microorganisms can be preserved by freezing and, after a preincubation period of 6 h, used as the inoculum source for in vitro estimation of ruminal protein degradation. Pediatr Res, 1996 May, 39(5), 843 - 8 Neutrophil respiratory burst in term and preterm neonates without signs of infection and in those with increased levels of C-reactive protein; Gessler P et al.; Developmental immaturities in neonatal host defense predispose the neonates to an increased mortality rate during bacterial infections . Early diagnosis is of great clinical importance, but, especially in neonates, is sometimes very difficult . The ability to generate reactive oxygen species, the so-called respiratory burst, is essential for neutrophils to kill infectious microorganisms . Therefore, changes of respiratory burst may reflect increased susceptibility of neonates to infections and may be useful for the early detection of infections . Superoxide anion production was determined by a flow cytometric method using dihydrorhodamine 123 (DHR) as an oxidative probe after priming of neutrophils with PBS buffer (spontaneous burst), with N-formyl-methionyl-leucyl-phenylalanine (fMLP), or with Escherichia coli . During the study period, the spontaneous percentage of activated cells in whole blood as well as the percentage of activated cells in stimulation with fMLP was lower in adults (n = 100; PBS, 1.0 +/- 0.1%; fMLP, 8.3 +/- 0.9%) compared with neonates without signs of infection (n = 143) . Among the latter, the percentage of activated cells (PBS and fMLP assay) varied with respect to gestational age and hours of life: lowest values were measured in preterm newborns with gestational age less than 32 wk and between 25 and 120 h of life . The same correlation to gestational age was true for total neutrophil cell counts . In neonates with increased levels of C-reactive protein during the first 5 d of life (n = 43), the percentages of activated cells after PBS and fMLP incubation were higher than those of neonates without signs of infection . The relationship of neutrophil respiratory burst and neutrophil cell counts to gestational age might reflect at least in part a reason for the increased susceptibility of neonates to infections . Furthermore, determination of respiratory burst may prove to be a new laboratory parameter of neonatal infection. J Prosthet Dent, 1996 May, 75(5), 495 - 8 Microleakage of a 4-methacryloxyethyl trimellitate anhydride bonding agent with amalgams; Chang JC et al.; Microleakage contributes to deterioration of materials, recurrent decay, growth of microorganisms at the interface, and postoperative tooth sensitivity . This study examined the microleakage between amalgams and tooth surfaces with a cavity liner, a 4-methacryloxyethyl trimellitate anhydride bonding agent (Amalgambond) and six different types of amalgams . Class 1 cavity preparations in extracted human molars were filled with different combinations of liners and amalgams and were stored at 37 degrees C in physiologic saline solution . After 1 week half of each amalgam restoration was removed . Within the same group the same cavity treatment was performed and the same type of amalgam was packed as before . Microleakage was determined after 2000 thermal cycles . Statistical analysis indicated that Amalgambond significantly reduced microleakage of different amalgams compared with the Copalite-lined and unlined controls . No microleakage was detected at the interface between the existing and replacement amalgams. Parasitology, 1996 May, 112 ( Pt 5), 481 - 8 Trypanosoma brucei s.l: evolution, linkage and the clonality debate; Stevens JR et al.; The Index of Association (IA) has been proposed by Maynard Smith et al . (1993) as a general method for characterizing the population structures of microorganisms as either: clonal, epidemic, cryptic species or panmictic . With reference to the current debate surrounding the mode of reproduction in parasitic protozoa, this study explores (i) the suitability and limitations of the IA for characterizing populations of Trypanosoma brucei s.l., and (ii) the idea that the significance of genetic differences between populations may be better understood if the evolution, spread and temporal stability of certain parasite genotypes are also considered . Four populations of T . brucei from Cote d'Ivoire, Uganda and Zambia are analysed using the IA and a complementary test for linkage disequilibrium, test f of Tibayrenc, Kjellberg & Ayala (1990) . The two populations from Uganda are characterized as epidemic, while the others appear more or less clonal; the merits of the two methods are compared . The implications of the various population classifications are discussed with reference to genotype longevity in each region; the evolution and biomedical consequences of the genetic non-homogeneity of T . brucei are reviewed. World J Surg, 1996 May, 20(4), 418 - 21 MODS/SIRS: result of an overwhelming inflammatory response? Goris RJ. Multiple organ dysfunction syndrome and the systemic inflammatory response syndrome are expressions of an inappropriate, generalized inflammatory response to severe inflammatory stimuli, which may be bacterial or nonbacterial in nature . The clinical signs and symptoms, morphologic alterations, and changes in oxygen transport seem to be the direct effect of phagocyte activation . So far, identifying the microorganisms and neutralizing their toxins has not been helpful in improving prognosis . As an essential adjunct to treating the bacterial or nonbacterial causes, finding safe ways of modulating the phagocyte response should be considered. Microb Ecol, 1996 May, 31(3), 291 - 304 Protein Profile Variation in Cultivated and Native Freshwater Microorganisms Exposed to Chemical Environmental Pollutants Ogunseitan OA. Assimilation of 35S-precursors into microbial proteins was used to investigate toxicity and adaptational responses that occur in nutrient enriched and natural freshwater samples experimentally contaminated with benzene, toluene, trichloroethylene (TCE), or xylene . Experiments were conducted to analyze (1) the potential of using microbial community protein profiles for responsive identification of chemical pollutant exposure, (2) the inhibition of microbial productivity through reduction in rate of protein synthesis caused by specific chemical pollutants, and (3) whether selection of subpopulations in freshwater microbial communities challenged with chemical pollutants leads to adaptive strategies mediated by production of particular polypeptides . The results show that distinct banding patterns of polypeptides in the range of 30 to 100 kilodaltons that were obtained following collective cultivation of freshwater microorganisms differ with each chemical pollutant . Protein yield and radioisotope incorporation were reduced within ten minutes of micro-bial exposure to chemical pollutants in the following order: xylene < toluene < benzene < TCE . Adaptation of the freshwater microbial community to chemical pollutants prior to radioisotope incorporation produced differences in polypeptide profiles, in the banding patterns of radioactive polypeptides, and in the rate of radioisotope incorporation . The rate of radioisotope incorporation by freshwater microorganisms pre-adapted to chemical pollutants was lowest with xylene (88.1% reduction), followed by TCE (84.0% reduction),toluene (67.3% reduction), and benzene (43.5% reduction) . In long-term radioisotope incorporation experiments, protein yield and polypeptide radioactivity was higher in the presence of chemical pollutants than in uncontaminated control samples, suggesting increased metabolic productivity attributable to the chemical pollutants. South Med J, 1996 May, 89(5), 503 - 4 Microbiologic assessment of the transabdominal ultrasound transducer head; Patterson SL et al.; The objectives of this study were to determine (1) the rate of bacterial isolation from the abdomen of women having obstetric ultrasonography, (2) the rate of bacterial transmission to the transducer head, and (3) the eradication rate after routine wiping of the transducer head . A total of 191 obstetric patients participated in this study . At the start of each day, the transducer head and the coupling gel were cultured . Aerobic cultures were obtained from each patient's periumbilical and suprapubic areas before the transabdominal scan and from the transducer head before and after wiping off the gel with a dry cloth . Daily transducer head and gel cultures were negative . Of the abdominal skin cultures, 175 (92%) were positive; 35 (18%) were positive for serious organisms, and 140 (74%) were positive for organisms of low virulence . Sixty percent of the transducer head cultures from women with abdominal skin pathogens were positive before the gel was wiped off . None of the cultures from the transducer head were positive after removal of the gel . We conclude that many women carry potentially virulent pathogens on the abdominal skin and that transmission of these organisms to the transducer head commonly occurs . Physical removal of the gel from the transducer head effectively eradicates these microorganisms, minimizing patient-to-patient transmission. Appl Environ Microbiol, 1996 May, 62(5), 1818 - 21 Microbial degradation of hydrochlorofluorocarbons (CHCl2F and CHCl2CF3) in soils and sediments; Oremland RS et al.; The ability of microorganisms to degrade trace levels of the hydrochlorofluorocarbons HCFC-21 and HCFC-123 was investigated . Methanotroph-linked oxidation of HCFC-21 was observed in aerobic soils, and anaerobic degradation of HCFC-21 occurred in freshwater and salt marsh sediments . Microbial degradation of HCFC-123 was observed in anoxic freshwater and salt marsh sediments, and the recovery of 1,1,1-trifluoro-2-chloroethane indicated the involvement of reductive dechlorination . No degradation of HCFC-123 was observed in aerobic soils . In some experiments, HCFCs were degraded at low (parts per billion) concentrations, raising the possibility that bacteria in nature remove HCFCs from the atmosphere. Appl Environ Microbiol, 1996 May, 62(5), 1656 - 63 Detection and localization of syntrophic propionate-oxidizing bacteria in granular sludge by in situ hybridization using 16S rRNA-based oligonucleotide probes; Harmsen HJ et al.; In situ hybridization with fluorescent oligonucleotides was used to detect and localize microorganisms in the granules of two lab-scale upflow anaerobic sludge blanket reactors that had been fed for several months with either sucrose or a mixture of volatile fatty acids . Sections of the granules were hybridized with 16S rRNA-targeted oligonucleotide probes for Bacteria, Archaea, specific phylogenetic groups of methanogens, and two syntrophic propionate-oxidizing strains, MPOB and KOPROP1 . Cells of the syntrophic strain KOPROP1 were not detected in either type of sludge granules . Hybridizations of the sucrose-fed granules showed an outer layer of mainly bacterial microcolonies with different morphologies . More inwards of these granules, a layer of different methanogenic microcolonies mixed with large colonies of the syntrophic strain MPOB could be detected . The MPOB colonies were intertwined with hydrogen- or formate-consuming methanogens, indicating their syntrophic growth . The granules fed with volatile fatty acids showed an outer layer of mainly bacteria and then a thick layer of Methanosaeta-like methanogens mixed with a few bacteria and a layer of methanogens mixed with syntrophic MPOB microcolonies . The centers of both sludge types consisted of large cavities and methanogenic microcolonies . These results indicate a juxtapositioning of syntrophic bacteria and methanogens and provide additional evidence for a layered microbial architecture of anaerobic granular sludge. Laryngoscope, 1996 May, 106(5 Pt 1), 599 - 604 Human nasal epithelium adsorbs complement C3-related fragments and expresses cell membrane complement regulatory proteins; Varsano S et al.; Recent evidence suggests that complement is activated in human nasal airways in inflammatory states . Activated complement protects the nasal mucosa against microorganisms, but also has the potential to lyse the host's normal cells . Complement-mediated cell lysis depends on adsorption of complement to the cell membrane and on uninterrupted activation of the complement cascade upon the same cell membrane . In the present study, the authors investigated first whether key complement components, C3-related fragments, are adsorbed to nasal epithelial cell membrane . Second, we investigated whether nasal epithelium expresses cell membrane complement regulatory proteins that are known as interruptors of complement activation . Studies were done using fresh nasal mucosa obtained at turbinectomies from allergic rhinitis and vasomotor rhinitis patients . In addition, in order to establish an in vitro model, studies were also done using primary cell cultures of nasal epithelium . We have found that complement C3-related fragments are present on cell membranes of fresh nasal epithelium and that C3-related fragments are adsorbed to the epithelial cell membrane in nasal mucosa tissue segments and in cell cultures that were incubated with autologous serum . Adsorption of C3-related fragments to the cell membrane of cultured nasal epithelial cells was found by flow cytometry analysis to be concentration-dependent . In addition, we found that nasal epithelium in fresh tissue and in cell culture express three cell membrane complement regulatory proteins: membrane cofactor protein (MCP, CD46), decay-accelerating factor (DAF, CD55), and CD59 . Our findings in fresh nasal epithelium suggest that complement activation may occur upon the nasal epithelial cell membrane during inflammation in vivo and that nasal epithelium might regulate this complement activation . Our in vitro cell culture model will allow further investigations of complement activation and regulation upon the human nasal epithelial cell membrane. J Pediatr, 1996 May, 128(5 Pt 1), 660 - 9 Topical ointment therapy benefits premature infants; Nopper AJ et al.; OBJECTIVE: Premature infants have an ineffective epidermal barrier . The aim of this study was to investigate the cutaneous and systemic effects of preservative-free topical ointment therapy in premature infants . STUDY DESIGN: We conducted a prospective, randomized study of 60 infants less than 33 weeks' estimated gestational age . The treated infants received therapy for 2 weeks with twice-daily preservative-free topical ointment therapy while the control group received no topical treatment or as-needed therapy with a water-in-oil emollient . Data collection included transepidermal water loss (TEWL) measurement, skin condition evaluations, fungal and quantitative bacterial skin cultures, analysis of fluid requirements, patterns of weight low or gain, and the incidence of blood and cerebrospinal fluid cultures positive for microorganisms . RESULTS: We found that topical ointment therapy significantly decreased TEWL during the first 6 hours after the initial application . TEWL was decreased by 67% (p = 0.0001) when measured 30 minutes after application and 34% (p = 0.001) when measured 4 to 6 hours after application . We also observed significantly superior skin condition scores in the treated group on study days 7 and 14 (p = 0.001) and 0.0004, respectively) . Quantitative bacterial cultures revealed significantly less colonization of the axilla on day 2, 3, or 4 and on day 14 (p = 0.008 and 0.04, respectively) . The incidence of positive findings in blood and/or cerebrospinal fluid cultures was 3.3% in the treated group of infants versus 26.7% in the control group (p = 0.02) . There was no statistical difference in the fluid requirements or patterns of weight gain or loss during the 2 weeks of the study . CONCLUSIONS: Preservative-free topical ointment therapy decreased TEWL for 6 hours after application, decreased the severity of dermatitis, and decreased bacterial colonization of axillary skin . Infants treated with ointment had fewer blood and cerebrospinal fluid cultures positive for microorganisms . These data support the use of topical ointment therapy in very premature infants during the first weeks after birth. Am J Surg Pathol, 1996 May, 20(5), 572 - 87 Lymphoid changes of the nasopharyngeal and palatine tonsils that are indicative of human immunodeficiency virus infection . A clinicopathologic study of 12 cases; Wenig BM et al.; We report 12 cases in which the histomorphologic changes of the nasopharyngeal tonsils (adenoids) or palatine tonsils suggest infection with the human immunodeficiency virus (HIV) . The patients included 10 men and two women, aged 20 to 42 years (median, 33 years) . The clinical presentation included airway obstruction, pharyngitis, fever, and a tonsillar or adenoidal mass lesion . Histologic evaluation of the excised adenoids or tonsils in 10 of the cases demonstrated a spectrum of changes including florid follicular hyperplasia, follicle lysis, attenuated mantle zone, and the presence of multinucleated giant cells (MGC) . The latter characteristically localized adjacent to the surface or tonsillar crypt epithelium . Two of the 12 cases showed marked lymphoid depletion with absent germinal centers, plasmacytosis, and stromal vascular proliferation . Immunohistochemical evaluation for HIV p24 core protein showed reactivity in 10 of 12 cases localized to follicular dendritic cell network (FDC), the MGC, scattered interfollicular lymphoid cells, and cells identified within the surface or crypt epithelium . Localization of viral RNA by in situ hybridization paralleled the HIV p24 immunohistochemical findings . Additional significant findings included the presence of both CD-68 and S-100 protein in the MGC and the presence of S-100 protein in dendritic cells . Other than HIV, no microorganisms were identified . At the time of presentation, eight patients were not known to be a risk for HIV infection, nor were they known to be HIV infected or suffering from AIDS . In these patients, HIV infection was suspected on the basis of the histologic changes seen in the resected tonsillar and adenoidal tissue . Serologic evaluation (by enzyme-linked immunosorbent assay), confirmed the presence of HIV infection . Our findings suggest the possibility of HIV dissemination through the upper aero-digestive tract mucosa via target cells, such as intraepithelial dendritic cells, submucosal macrophages, and T-lymphocytes . Subsequent presentation of viral antigens to the tonsillar and adenoidal lymphoid tissues results in enlargement of these structures that clinically may simulate a neoplastic proliferation but causes histomorphologic changes that are highly suspicious for HIV infection even in asymptomatic HIV-positive patients. Surgery, 1996 May, 119(5), 585 - 91 Therapeutic efficacy of an antineutrophil monoclonal antibody, Urge-8, against acute necrotizing pancreatitis in rats; Han SL et al.; BACKGROUND . Although they have critical roles in the defense mechanism against invading microorganisms, neutrophils may facilitate exacerbation of critical conditions associated with acute necrotizing pancreatitis by a discharge of granule contents into the organ tissues . Because of this constitution of neutrophils, the therapeutic efficacy of Urge-8, a mouse monoclonal antibody to neutrophils, on the survival of rats with experimentally induced acute necrotizing pancreatitis was investigated in vivo . METHODS . Acute pancreatitis was induced by injection of trypsin mixed with sodium chenodeoxycholic acid into pancreatic ducts . Urge-8 was infused intravenously 30 minutes after pancreatitis was induced, a series of vital signs was taken, and plasma amylase level was estimated . RESULTS . Hemorrhagic necrosis of the pancreas and intraabdominal bleeding were observed 1 hour after the pancreatitis-inducing drugs were injected, and death occurred at 240.9 +/- 24.6 minutes (mean +/- SD)in the control group . With Urge-8 administration, however, the survival time was significantly prolonged to 395.2 +/- 64.4 minutes (p = 6.0 x 10-(10) versus control) . Failure in the vital signs (mean arterial pressure, heart rate, and body temperature) was significantly ameliorated by injection of Urge-8 . The plasma amylase level was elevated after pancreatitis was induced and peaked at 3 hours (4915 +/- 1966 IU/L in mean +/- SD) . This level was suppressed during the first 3 hours by injection of Urge-8 (3372 +/- 1223 IU/L); however, the amylase level increased thereafter, becoming comparable with the peak in the control group, and then death occurred . Arterial blood gas and plasma electrolyte analyses showed that pH, base excess, and plasma potassium levels in the group treated with monoclonal antibody were significantly improved . CONCLUSIONS . It was suggested that neutrophils play some critical role in the exacerbation of acute necrotizing pancreatitis and its related symptoms . Although not capable of preventing death in our model, treatment with the antineutrophil monoclonal antibody Urge-8 after the onset of acute pancreatitis prolonged the survival time significantly. Biochemistry, 1996 Apr 9, 35(14), 4492 - 501 Carbohydrate fluxes into alginate biosynthesis in Azotobacter vinelandii NCIB 8789: NMR investigations of the triose pools; Beale JM Jr et al.; The metabolite flux of carbohydrates through primary catabolism and into hexose resynthesis has been investigated for alginic acid biosynthesis in Azotobacter vinelandii . To do these studies, we fed the microorganism a variety of 13C-labeled glucose precursors, including {U-13C6}glucose . The incorporations of the precursors were determined by 1D 13C-NMR, 2D 13C-DQF-COSY, and inverse triple-quantum correlation experiments . The results clearly show that the entire catabolism of hexose is through the Entner-Doudoroff (E-D) pathway and that the triose pools are in equilibrium . Reentry into gluconeogenesis prior to alginate synthesis occurs totally from the glyceraldehyde 3-phosphate generated by the E-D pathway . The obligatory intermediacy of triose intermediates in alginate biosynthesis was proved . The experiments and results presented in this paper constitute a new method for distinguishing the E-D pathway from glycolysis in bacteria. Enferm Infecc Microbiol Clin, 1996 Apr, 14(4), 220 - 6 {Disseminated Mycobacterium genavense infection in patients with HIV infection . Description of 5 cases and review of the literature}; Rodriguez P et al.; BACKGROUND . Five cases of disseminated infection by Mycobacterium genavense in patients with HIV infection are reported with a review of the literature . MATERIAL AND METHODS . A description of the clinical, epidemiologic and therapeutic characteristics of five cases are presented . The initial isolation of the microorganism was performed in Bactec 13A from blood and bone marrow aspirates . Subcultures were made in different media and the growth characteristics evaluated . Sensitivity to NAP was determined by radiometric techniques and gas chromatography allowed a possible identification . Definitive identification was based on PCR amplification of the gene which codifies the 65kDa protein and the posterior restriction of the amplified fragments by using BstEII and HaeIII . RESULTS . All five patients were males with HIV infection and a lymphocyte count of less than 25 cells/mm3 with an non-specific clinical picture similar to that produced by M . avium complex (MAC) . Empiric antiMAC treatment was administered in four of the patients with good clinical response . All five strains were sensitive to NAP . The greatest growth rate was obtained in the subcultures with acid pH in liquid medium . Gas chromatography was very similar to that of M . simiae . Amplification of the gene which codifies the 65 kDa protein and posterior restriction with BstEII resulted in 2 fragments of 325 and 125 bp, while restriction with HaeIII resulted in two fragments of 140 and 105 bp . CONCLUSIONS . Mycobacterium genavense represents 9% of the disseminated infections by mycobacteria in AIDS patients . The clinical manifestations, empiric treatment and response is similar to that of infection by M . avium complex . Growth is favored by acid pH in liquid medium . Susceptibility to NAP leads to possible identification which should be confirmed by molecular techniques. J Biomed Mater Res, 1996 Apr, 30(4), 493 - 9 Glow-discharge-modified activated carbon cloths as skin substitutes; Piskin E et al.; In this study, activated carbon cloths (ACCs) were modified in a glow-discharge apparatus by using 2-hydroxyethyl-methacrylate (HEMA), dimethyl-aminoethyl methacrylate (DMAEMA), and hydroxymethyldisiloxane (HMDS) plasmas . Scanning electron micrographs exhibited the formation of the polymeric films on the ACCs after glow-discharge modification . The adsorption experiments were performed using model solutes, i.e., creatinine, vitamin B-12, and trypsin . No significant change was observed in the adsorption capacities of the ACC/PHEMA and ACC/PDMAEMA composites compared with the original ACC adsorption capacity . However, there was a pronounced decrease in the case of the ACC/PHMDS . Oxygen permeabilities of both the original and modified ACCs were measured in a flow-through gas chamber . The oxygen permeabilities of the original and modified forms were 817 and 3.5-5 cm3/s.cm2.cm Hg x 10(-7), respectively . Water-vapor permeabilities of the composites were obtained by using a standard water-cup assembly . Permeabilities varying between 921 and 10,300 g/m2.day were found . Microorganism impermeabilities of the ACCs were demonstrated by using model PS monosize polymeric particles with a diameter of 0.2 micron . The particle permeability of the original ACC was 65.6 mg/m2.day . Almost no particle permission was observed through the modified ACCs. Methods, 1996 Apr, 9(2), 305 - 10 What Models of Granulomatous Inflammation Provide the Immunologist Metwali A, Elliott D, Blum A, Weinstock JV. Granulomas usually serve to protect the host from the spread of persistent microorganisms or other enduring injurious substances . They are complex inflammatory reactions that use many immune mechanisms to control the inciting nudis . These lesions can persist for weeks, months, or even years . Thus, understanding the mechanisms that enhance, diminish, or modulate granulomas could aid in the treatment of many diseases . Moreover, experimental animal models of granulomatous inflammation allow sophisticated investigation of some disease processes not possible using human subjects . Granulomatous inflammations are chronic, composed of activated leukocytes that are selected for deposition at the site of injury . They use various effector mechanisms, delicately balanced by many immunoregulatory circuits . Under some experimental conditions, granulomas can be isolated readily from host tissue and subjected to sophisticated immunological analysis . Therefore, it is possible to dissect the actual, local control mechanisms that govern the granulomatous response . Lesions learned studying granulomas are applicable to other types of inflammation, since granulomas use immunoregulatory networks and soluble cytokines common to many inflammatory states . Using these experimental models, it is readily apparent that studies utilizing splenocytes or peripheral blood leukocytes may not reveal the true, dominant immunoregulatory mechanisms employed at sites of active inflammation . The leukocytes of spleens and blood are a mixture of cells in various stages of activation, many of which are not destined to participate in a selective immune response . Also, granulomas are sustained inflammatory reactions permitting analysis of the unique features of chronic maintenance, as opposed to acute phase inflammation. Eur J Oral Sci, 1996 Apr, 104(2 ( Pt 1)), 144 - 7 PCR primers for the amplification of the 16S rRNA gene of oral bacteria and for the specific identification of Actinobacillus actinomycetemcomitans; Albandar JM et al.; The aim of this study was to develop a PCR reaction specific to Actinobacillus actinomycetemcomitans, which targets a widely conserved gene of this bacterium . Two sets of primers were designed based on published sequences of the 16S rRNA of several microorganisms . The first set amplifies a major part of the 16S small subunit rRNA gene of several strains of bacteria commonly found in the periodontal pocket . This reaction produced a 1306 bp-long product and served as a positive control . The second set was specific to A . actinomycetemcomitans and produced a 449 bp-long product . H . aphrophilus and E . coli yielded positive results with the control primers and negative results with the A . actinomycetemcomitans-specific primers . DNA-DNA hybridization was used to validate the identify of the amplified sequences . B . cereus, which is a common contaminator in the laboratory, and human DNA did not generate PCR products in either reaction . The developed primers seen useful for the identification of A . actinomycetemcomitans strains. Zentralbl Bakteriol, 1996 Apr, 283(4), 417 - 30 Generation of DNA probes for detection of microorganisms by polymerase chain reaction fingerprinting; Giesendorf BA et al.; Identification of medically relevant microorganisms is important for diagnosis, treatment and prevention of infectious diseases . This has initiated the development of a large number of identification and typing techniques based on phenotypic and genetic characteristics . In general, these last mentioned nucleic acid-mediated techniques provide more detailed and consistent information on strain-specific characteristics . However, the development of clinically useful microbial DNA/RNA probes requires nucleotide sequence information and a set of well defined reference organisms for test validation in comparison with the current gold standard . This is a requirement for the development of accurate nucleic acid hybridisation and/or amplification tests . Recently, it has been demonstrated that polymerase chain reaction (PCR)-mediated genetic typing of microorganisms can lead to the immediate isolation of species-specific DNA probes by comparison of DNA fingerprints . This combines the sensitivity of PCR with the specificity of DNA probing without the need to generate nucleic acid sequence information prior to probe development . The implications of this procedure for clinical microbiology and epidemiological surveillance will be discussed . It is shown that specific probes can be developed for various taxonomic levels and that detection and identification can be combined into a single, fast procedure . The versatility and widely applicable principles of this procedure will be highlighted and exemplified by some newly developed tests and a review of the current literature. Clin Infect Dis, 1996 Apr, 22(4), 650 - 3 Increased levels of nitrite in the sera of children infected with human immunodeficiency virus type 1; Torre D et al.; Nitric oxide (NO) is a newly discovered gas that plays an important role in cell communication and host resistance to infection . The production of NO was examined in the sera of seven children infected with human immunodeficiency virus type 1 (HIV-1) and in the sera of 14 children who became seronegative for HIV-1 during the first year of life . In addition, we determined serum levels of various cytokines, such as interleukin (IL)-1 beta, tumor necrosis factor (TNF)-alpha, and gamma interferon (IFN-gamma), inasmuch as these cytokines are potent inducers of NO production . Production of NO, detected as circulating serum levels of nitrite, was measured with use of the Griess reagent . Serum levels of cytokines were determined by enzyme immunoassay . Increased serum levels of nitrite were observed in children with HIV-1 infection (0.4 +/- 0.2 mumol/L; P = .013), and in those who became seronegative for HIV-1 during the first year of life (0.5 +/- 0.3 mumol/L; P = .04) . Furthermore, serum levels of IL-1 beta and TNF-alpha were significantly elevated in children with HIV-1 infection (37.5 +/- 23.6 pg/mL and 91.2 +/- 45.1 pg/mL, respectively) . Prophylactic administration of intravenous immune globulin provoked a significant decrease of circulating levels of nitrite in children with HIV-1 infection . In conclusion, NO may play a role as a cytostatic or cytotoxic factor for invading microorganisms, and thus it is probably involved in limiting and/or eradicating infection. J Clin Gastroenterol, 1996 Apr, 22(3), 182 - 5 Helicobacter pylori serology in chronic gastritis with antral atrophy and negative histology for Helicobacter-like organisms; Testoni PA et al.; It has been suggested that there may be a correlation between Helicobacter pylori (Hp) infection and precancerous lesions of the stomach . However, histological evaluation of bacterial colonization in chronic atrophic gastritis shows a relatively low prevalence of the microorganism, which does not support the hypothesis . The aim of our study was to investigate the Hp serology in 95 patients with chronic gastritis with antral atrophy, with (27 cases) and without (68 cases) intestinal metaplasia, and without Helicobacter-like organisms in antral and corpus biopsy specimens . For all subjects, serum anti-Hp immunoglobulin IgG was identified by a fluorescent immunoenzymatic method (Helori-test; Eurospital), and mucosal atrophy and activity were graded histologically (Sydney System score) . The serum Hp-antibody status documented the presence of current bacterial infections in 64 of 95 (67.4%) patients and previous infections in another 17 subjects . In only 14.7% of cases was there no evidence of current or previous infection . These subjects had less severe mucosal atrophy and lower inflammatory scores . In addition, there were no cases of intestinal metaplasia in such subjects . The high prevalence of Hp infection confirms the primary role of the microorganism in the pathogenesis of chronic gastritis with antral atrophy, although the bacterium is no longer present in the advanced stages of such disease . The histological evaluation of Hp colonization following the criteria of the Sydney System appears from our study to underestimate the true prevalence of the infection in the stomach when there is mucosal atrophy. J Gastroenterol, 1996 Apr, 31(2), 294 - 8 Bacteria closely resembling Helicobacter pylori detected immunohistologically and genetically in resected gallbladder mucosa; Kawaguchi M et al.; A microorganism with close immunohistological and genetic resemblance to Helicobacter pylori was found in the resected gallbladder mucosa of a 41-year-old woman . The woman was admitted to hospital complaining of fever and right hypochondrial pain . Cholecystectomy was carried out under the diagnosis of gallstones and cholecystitis . A microorganism resembling H . pylori (stained with H&E, Giemsa, and Wartin-Starry) was detected incidentally on pathological examination . The microorganism was also positive for immunohistochemical staining . An amplification reaction was seen on genetic examination by the polymerase chain reaction (PCR) method (urease beta-genes) . Our findings suggest that H . pylori may be present in tissues other than gastric mucosa. J Nutr, 1996 Apr, 126(4 Suppl), 1326S - 34S Ruminal microbial metabolism of peptides and amino acids; Wallace RJ; Peptides and amino acids, either present in the diet or arising from proteolysis in the rumen, are potential nutrients for the growth of ruminal microorganisms but also are liable to be degraded to ammonia and lost from the rumen . In both cases, peptides generally are metabolized by the mixed population more rapidly than amino acids . The predominant mechanism of peptide degradation is biphasic, via dipeptidyl peptidases, which cleave dipeptides from larger peptides followed by the action of dipeptidases . Peptides blocked at the N-terminus, or with glycine or proline as the N-terminal or penultimate N-terminal residue, are more slowly degraded than others . Dipeptidyl peptidase activity occurs only in Prevotella ruminicola among the common ruminal microbial species . In contrast, dipeptidase is present in many species, including P . ruminicola, and is particularly high in ruminal protozoa . Deamination of amino acids is carried out by a combination of numerous low activity bacteria and protozoa and a much smaller number of high activity species . Ammonia production is probably carried out mainly by the low activity species, which again include P . ruminicola, but proliferation of the high activity species may be a problem when certain diets are fed . Excessive ammonia production can be controlled by ionophores, which slow peptide metabolism, suppress growth of the high activity deaminating bacteria and cause the residual ionophore-resistant population to break down amino acids more slowly. J Nutr, 1996 Apr, 126(4 Suppl), 1208S - 12S Benefits and liabilities of vitamin A and carotenoids; Olson JA; Vitamin A and carotenoids are often cited as members of a family of antioxidant vitamins that can show protective effects against oxidative stress and some chronic diseases . The great advantages of aerobic metabolism are offset in part by adverse physiological effects that can be caused by highly reactive forms of oxygen and its reduction products . Nature has developed a variety of sophisticated defenses against these undesirable side effects of oxygen . Vitamin A and carotenoids can serve chemically both as electron acceptors and donors (i.e., as oxidants and reductants), although in nature vitamin A seems to be protected from oxidation by other physiological antioxidants rather than serving a protective role itself . Furthermore, large doses of vitamin A are toxic . Carotenoids may serve a broader protective role in humans as they do in plants and microorganisms, but the evidence supporting such a role in humans is mixed . The widely used term antioxidant vitamins is too narrow in scope for the properties attributed to them . A much better term is physiological modulators, which broadens both the set of compounds that are included and the possible nature of their actions, whether beneficial or adverse. Anesthesiology, 1996 Apr, 84(4), 760 - 71 Histopathologic and microbiologic aspects of ventilator-associated pneumonia; Fabregas N et al.; BACKGROUND: The relationship between microbiology and histology in patients with ventilator-associated pneumonia has been sparsely described . METHODS: Twenty-five patients who died in the intensive care unit after their lungs had been mechanically ventilated for 72 h were studied . Twenty of the 25 died with clinical suspicion of pulmonary infection . A total of 375 immediate postmortem pulmonary biopsies were obtained after death and processed for quantitative microbiology and histology . Four evolutionary stages of pneumonia were defined: early, intermediate, advanced, and resolution . RESULTS: At least one specimen with histologic evidence of pneumonia was found in all but two patients (92%) . Histologic pneumonia was a widespread and frequent process (46%) of biopsies examined) involving predominantly the lower lobes (55% of all biopsies with pneumonia) and showing different histopathologic stages of progression coexisting in the same lung lobes . Lung cultures were frequently polymicrobial (149 of 375, 40% of the pulmonary biopsy cultures, and 20 of 25, 80% of the cases) and not always yielding the same pathogen (19 microorganisms) when comparing one lung to the other . Histopathology and microbiologic biopsy cultures showed a weak relationship (28% and 49% of species had counts > or = 10(3) cfu/g in samples without pneumonia from patients with and without prior antibiotic treatment, respectively) . Histopathologic evolutionary stages were not associated with any differences in quantitative culture results of pulmonary biopsies, independently of prior administration of antibiotics . Higher bacterial concentrations of biopsy cultures were associated with the absence of prior antibiotic treatment . CONCLUSIONS: Ventilator-associated pneumonia is a frequent diffuse and polymicrobial process showing different coexisting degrees of evolution and involving preferentially the lower lobes . Microbiology and histology can be dissociated even in the absence of prior antibiotic treatment . Lung histology appears more reliable than bacteriology as a diagnostic reference test. J Ky Med Assoc, 1996 Apr, 94(4), 148 - 52 The polymerase chain reaction: a revolutionary new procedure for the laboratory diagnosis of infectious disease; Buck GE; The polymerase chain reaction (PCR) is a revolutionary new means of amplifying, ie, replicating, selected DNA sequences in vitro . This procedure is rapid, requiring approximately 5 hours for completion, and exquisitely sensitive . Studies have shown that as few as one microorganism can be detected . Thus, it has the potential for revolutionizing the diagnosis of infections . Because of its expense, its immediate role will probably be restricted to infections where the causative organism cannot be cultured or is difficult to detect by conventional means . As further progress occurs, however, this technique may well become a major new tool for diagnosing infections. J Bacteriol, 1996 Apr, 178(8), 2402 - 8 Phylogenetic analysis of dissimilatory Fe(III)-reducing bacteria; Lonergan DJ et al.; Evolutionary relationships among strictly anaerobic dissimilatory Fe(III)-reducing bacteria obtained from a diversity of sedimentary environments were examined by phylogenetic analysis of 16S rRNA gene sequences . Members of the genera Geobacter, Desulfuromonas, Pelobacter, and Desulfuromusa formed a monophyletic group within the delta subdivision of the class Proteobacteria . On the basis of their common ancestry and the shared ability to reduce Fe(III) and/or S0, we propose that this group be considered a single family, Geobacteraceae . Bootstrap analysis, characteristic nucleotides, and higher-order secondary structures support the division of Geobacteraceae into two subgroups, designated the Geobacter and Desulfuromonas clusters . The genus Desulfuromusa and Pelobacter acidigallici make up a distinct branch within the Desulfuromonas cluster . Several members of the family Geobacteraceae, none of which reduce sulfate, were found to contain the target sequences of probes that have been previously used to define the distribution of sulfate-reducing bacteria and sulfate-reducing bacterium-like microorganisms . The recent isolations of Fe(III)-reducing microorganisms distributed throughout the domain Bacteria suggest that development of 16S rRNA probes that would specifically target all Fe(III) reducers may not be feasible . However, all of the evidence suggests that if a 16S rRNA sequence falls within the family Geobacteraceae, then the organism has the capacity for Fe(III) reduction . The suggestion, based on geological evidence, that Fe(III) reduction was the first globally significant process for oxidizing organic matter back to carbon dioxide is consistent with the finding that acetate-oxidizing Fe(III) reducers are phylogenetically diverse. Arch Pathol Lab Med, 1996 Apr, 120(4), 364 - 8 Histologic, microbiologic, and clinical correlates of the diagnosis of sarcoidosis by transbronchial biopsy; Hsu RM et al.; OBJECTIVE--To determine the frequency of positive microbiologic cultures in patients with epithelioid granulomas and negative histochemical stains for microorganisms in transbronchial biopsy specimens . Secondary objectives were to compare the histologic features of sarcoidosis with those of infectious granulomas and to assess the reliability of histology in establishing the diagnosis of sarcoidosis . DESIGN--Retrospective study . Specific histologic features of transbronchial biopsy specimens were correlated with clinical and microbiologic data, final diagnosis, and an estimate of the probability, on admission, that the patient had sarcoidosis . SETTING--A large, urban, tertiary-care, university-affiliated hospital . PATIENTS--Ninety-two adult patients in whom epithelioid granulomas, negative for microorganisms on Ziehl-Neelsen and Gomori methemaine silver stain, were found in transbronchial biopsy specimens . Patients were identified through a search of surgical pathology files from 1975 to 1987 . RESULTS--Ten patients (10.9%) had mycobacterial or fungal granulomas, while 82 had sarcoidosis . In all patients with a high clinical probability of sarcoidosis, the diagnosis was confirmed . Transbronchial biopsy specimens from patients with infectious granulomas had fewer granulomas (2.0 +/- 1.7 (SD) versus 7.1 +/- 6.6; P<.01), which involved a smaller proportion of lung tissue per case (9.5 +/- 10.0% versus 26.6 +/- 24.0%; P<.01) . Sarcoid granulomas often exhibited Schaumann bodies (69.5% versus 10%; P<.01) . Necrosis tended to predominate in infectious granulomas (19.5 versus 40%; not significant) . CONCLUSIONS--Numerous granulomas, Schaumann bodies, and a high clinical probability of sarcoidosis are significantly associated with that diagnosis . Necrosis does not exclude sarcoidosis . Clinicopathologic assessment of transbronchial biopsy specimens is useful in predicting the final diagnosis of sarcoidosis but does not obviate the need for microbiologic cultures, which were positive in 10.9% of patients in this study. Am J Clin Nutr, 1996 Apr, 63(4), 622S - 6S Recombinant human milk proteins - an opportunity and a challenge; Lonnerdal B; Several human milk proteins have physiologic functions in infants . These proteins are involved in defense against infectious agents and in the optimization of nutrient uptake from milk . Therefore, interest in producing recombinant human milk proteins to use in infant formula has been growing . Microorganisms and transgenic animals can now be used for the production of bioactive proteins . However, the benefits of each protein must be evaluated in cells, animal models, and infants before claims can be made that adding them to formula improves the health or nutrition of infants . Once benefits are shown, proper manufacturing conditions must be developed for introducing the protein or proteins into formula . Processing conditions must be evaluated to ensure that biologic activity is maintained . Dry blending, aseptic processing, sterile filtration, and other techniques will likely be necessary for introducing proteins that require specific tertiary structure for activity . The importance of posttranslational modifications must also be considered: some proteins may require proper glycosylation or phosphorylation for physiologic activity. J Biol Chem, 1996 Mar 22, 271(12), 7012 - 8 Accelerated evolution in inhibitor domains of porcine elafin family members; Tamechika I et al.; Through the analysis of the porcine gene encoding the elastase inhibitor elafin, we demonstrated that there are at least three closely related members of the elafin family, and their genes have arisen by accelerated evolution . A porcine genomic DNA library was screened with a previously cloned human elafin cDNA probe, and several positive clones were obtained that can be distinguished by a combination of restriction enzymes . Sequence analysis of these clones revealed the presence of three homologous members whose genes, all consisting of three exons and two introns, are almost identical except the exon 2 sequences encoding the inhibitor domain called "WAP motif"; the intron sequences are related to each other with sequence similarities of 93-98%, whereas the exon 2 sequences exhibited only 60-77% similarities among the three members . The extreme divergence in the exon 2 sequences compared to the highly conserved intron sequences may be generated by accelerated mutations confined in a short stretch of the genes following recent duplication events of a single ancestral gene . An RNase protection assay indicated that the messages of the elafin family members are abundantly expressed in the trachea and intestine, suggesting that the most likely selective forces for the accelerated evolution are extrinsic proteinases produced by invasive microorganisms. Appl Environ Microbiol, 1996 Mar, 62(3), 998 - 1003 Detection of Dekkera-Brettanomyces strains in sherry by a nested PCR method; Ibeas JI et al.; Brettanomyces sp . and its ascosporogenous sexual state, Dekkera sp., have been well documented as spoilage microorganisms, usually associated with barrel-aged red wines . In this report, we describe the genetic characterization, on the basis of DNA content per cell, electrophoretic karyotyping, and mitochondrial DNA restriction patterns, of a Dekkera yeast strain isolated from sherries and of a number of other Brettanomyces and Dekkera strains . By using a genomic DNA fragment of the isolated Dekkera strain, we developed a two-step PCR method which directs the specific amplification of target DNA from this strain and from other Brettanomyces-Dekkera strains . The method efficiently amplified the target DNA from intact cells, obviating DNA isolation, and yielded a detection limit of fewer than 10 yeast cells in contaminated samples of sherry. Gac Med Mex, 1996 Mar-Apr, 132(2), 119 - 25 {Gardnerella vaginalis in reports of cervico-vaginal cytology}; Monterrosa-Castro A et al.; Gardnerella vaginalis is a microorganism of great importance because of its participation in some gynecological diseases . Data contained in 3421 cervicovaginal cytology reports obtained from the Profamilia Clinic, Cartagena, Colombia between June 1993 and February 1994 were analyzed retrospectively and analytically . Cells suggestive of Gardnerella vaginalis were found in 723 reports, the greatest proportion being in the 25-29, 30-34, 35-39 year-old age groups (without statistical significance) . There is a high frequency of Gardnerella vaginalis as related to healthy cervix and flux . Among the population with Gardnerella vaginalis a low percentage of neoplasia and non-classified atypical cell were found inflammatory reaction was reported in more than half of the cases . In 95% of the reports, Gardnerella vaginalis was the only agent found, the remaining 5% had associated HVP, fungus and trichomonas . Because of the medical staff responsible for taking the samples, cervico-vaginal cytology is an effective method for studying the state of the vagina and cervix. Appl Microbiol Biotechnol, 1996 Mar, 45(1-2), 148 - 57 Killing of microorganisms by pulsed electric fields; Grahl T et al.; Lethal effects of pulsed electric fields (PEF) on suspensions of various bacteria, yeast, and spores in buffer solutions and liquid foodstuffs were examined . Living-cell counts of vegetative cell types were reduced by PEF treatment by up to more than four orders of magnitude (> 99.99%) . On the other hand, endo- and ascospores were not inactivated or killed to any great extent . The killing of vegetative cell types depends on the electrical field strength of the pulses and on the treatment time (the product of the pulse number and the decay time constant of the pulses) . For each cell type, a specific critical electric field strength (Ec) and a specific critical treatment time (tc) were determined . Above these critical values, the fractions of surviving cells were reduced drastically . The "limits" Ec and tc depend on the cell characteristics as well as on the type of medium in which the cells are suspended . Especially in acid media living-cell counts were sufficiently decreased at very low energy inputs . In addition to the inactivation of microorganisms, the effect of PEF on food components such as whey proteins, enzymes and vitamins, and on the taste of foodstuffs was studied . The degree of destruction of these food components by PEF was very low or negligible . Moreover, no significant deterioration of the taste of foodstuffs was detected after PEF treatment . Disintegration of cells by PEF treatment in order to harvest intracellular products was also studied . Yeast cells, suspended in buffer solution, were not disintegrated by electric pulses . Hence, PEF treatment is an excellent process for inactivation of microorganisms in acid and in thermosensive media, but not for complete disintegration of microbial cells. Appl Microbiol Biotechnol, 1996 Mar, 45(1-2), 80 - 5 Cloning and sequence analysis of the highly expressed melanin-synthesizing gene operon from Streptomyces castaneoglobisporus; Ikeda K et al.; Streptomyces castaneoglobisporus HUT6202 overproduces a diffusible melanin-like pigment . An operon, designated mel, containing a gene that encodes tyrosinase, which is involved in the synthesis of melanin pigment, was cloned from the chromosomal DNA of the microorganism into the high-copy plasmid pAK114 and expressed in S . lividans . The tyrosinase activity of the transformed cells was at approximately a 110-fold higher level than that of the same host carrying the plasmid pIJ702, which has the same replication origin as pAK114 and carries the mel operon from S . antibioticus . The sequence analysis of the S . castaneoglobisporus mel operon revealed that an open-reading frame consisting of 378 base pairs(bp), designated ORF378, was found upstream of the tyrosinase gene (TYRC) consisting of 819 bp . In the present study, we constructed a chimeric mel operon consisting of ORF378 from S . castaneoglobisporus and the tyrosinase gene (TYRA) from S . antibioticus . The chimeric mel operon or the S . antibioticus mel operon, which consists of ORF438 and TYRA, expressed the tyrosinase activity in Escherichia coli intracellularly when located under the control of lacZ promoter, and the tyrosinase activity from the former was at a 30-fold higher level than that from the latter . This suggests that the gene contributing to the high expression of the tyrosinase activity in S . castaneoglobisporus is ORF378, rather than TYRC. Appl Microbiol Biotechnol, 1996 Mar, 45(1-2), 41 - 6 Simultaneous production and decomposition of clavulanic acid during Streptomyces clavuligerus cultivations; Mayer AF et al.; Clavulanic acid (CA) was produced by Streptomyces clavuligerus in medium containing glycerol and soy meal or soy meal extract . With regard to growth and CA productivity, the microorganism showed significant differences if solid soy meal as such or its extract were applied as the major nitrogen source . If the extract is used, growth and CA production take place simultaneously and in the stationary phase the CA concentration is stagnant or reduces . If soy meal is used, growth is threefold faster and CA is only generated in the stationary phase . In the case of using the soy meal extract, the decrease of the CA concentration is mainly due to decomposition or re-metabolisation of CA in the presence of the microorganism . This conclusion is supported by in vivo and in vitro data on CA decomposition. AJNR Am J Neuroradiol, 1996 Mar, 17(3), 589 - 92 Pseudallescheria boydii infection of the brain: imaging with pathologic confirmation; Albernaz V et al.; Pseudallescheria boydii is a rare opportunistic microorganism that usually infects immunosuppressed hosts . In this patient with cerebral infection by P boydii, imaging findings included enhancement of the ependyma of a lateral ventricle and of the caudate nucleus. Microbiology, 1996 Mar, 142 ( Pt 3), 639 - 48 Experimental verification of a mathematical model for pelleted growth of Streptomyces coelicolor A3(2) in submerged batch culture; Tough AJ et al.; A published mathematical model for growth of pellets of filamentous microorganisms has been tested by comparison of model predictions with experimental data on growth of Streptomyces coelicolor in liquid batch culture . The original model considered the classification of pellets into a range of size classes . Growth resulted in movement of pellets to classes of increasing size, while shear forces produced mycelial fragments which entered the smallest size class, from which they grew to form further pellets . This model did not correctly describe changes in pellet size distributions during growth and was therefore modified in two ways . In the first, new pellets were assumed to be formed by the break-up, by shear forces, of existing pellets into two pellets of equal size, rather than removal of small hyphal fragments from the pellet surface . The second modification assumed that the outer shell of active mycelial biomass had a density less than 1 g cm-3 and that hyphal density within this shell decreased with distance from the pellet centre . The modified model generated predictions which agreed closely with experimental data on biomass concentration, pellet size distribution, pellet number and pellet radius during batch growth, thereby supporting the assumptions on which the model was based . The model did not accurately describe final biomass concentration, through lack of consideration of autolysis of mycelia at the centre of larger pellets in which growth was limited by diffusion of nutrients . Attempts to incorporate autolysis into the model improved prediction of biomass concentration but were not based on sound biological assumptions and increased the complexity of the model . Further experimental work is required for accurate description of the effects of autolysis on pellet growth. Trends Genet, 1996 Mar, 12(3), 97 - 101 Protein aspartate phosphatases control the output of two-component signal transduction systems; Perego M et al.; Phosphorylation or dephosphorylation of an aspartate regulates the output activity of the response regulator of two-component signaling systems . Signal input in these systems is dependent on signal-transducing kinases, which can respond to a variety of signal ligands and, in some cases, to small phosphorylated metabolic intermediates . The kinase component of many two-component signaling systems also displays a response regulator-phosphate phosphatase activity that inactivates the response regulator in response to signals . Newly discovered kinase-independent phosphatases allow additional signals to influence the extent of response-regulator phosphorylation . Such phosphatases are prevalent in signal transduction systems controlling complex processes, such as the initiation of development in microorganisms. Surv Ophthalmol, 1996 Mar-Apr, 40(5), 343 - 67 Meibomian gland dysfunction; Driver PJ et al.; Blepharitis is probably the most common disease entity seen in the general ophthalmologist's office . A significant proportion of these cases are secondary to meibomian gland disease . This review outlines our knowledge of the histopathology, lipid abnormalities and role of microorganisms in meibomian gland dysfunction . We will also review the physiology of meibomian gland secretion and present models of meibomian gland dysfunction which have enhanced our knowledge of this condition . The importance of diagnosing associated conditions such as aqueous tear deficiency, contact lens intolerance, rosacea, and seborrheic dermatitis is emphasized . Although this condition causes significant morbidity in the population, there are effective treatments available and these will be discussed. J Hepatol, 1996 Mar, 24(3), 324 - 7 Liver biopsy in liver transplantation: no additional risk of infections in patients with choledochojejunostomy; Ben-Ari Z et al.; BACKGROUND/AIMS: This study aimed to determine whether there is an increased infectious risk following liver biopsy in liver transplant patients with choledochojejunostomy . METHODS: We evaluated the incidence of liver-biopsy-related sepsis in a consecutive series of 27 patients who underwent choledochojejunostomy, either during the transplant procedure (17 patients) or later following biliary complications (10 patients) . We evaluated another 138 patients as a control group who had orthotopic liver transplantation during the same period and underwent duct-to-duct anastomosis . All liver biopsies had routine, prior ultrasound evaluation to detect dilated biliary ducts . RESULTS: In the 27 patients who underwent choledochojejunostomy, 96 liver biopsies were performed: the sepsis rate was 3.12% per biopsy (n = 96) or 7.4% per patient (n = 27) . However, despite a normal ultrasound, subsequent ERCP demonstrated biliary obstruction in one patient . Thus the rate of sepsis was 2.1% per biopsy or 3.7 per patient . In the control group 338 liver biopsies were performed: the sepsis rate was 1.5% per biopsy (n = 338) or 2.9% per patient (n = 138) . The difference was not significant . All septic episodes had positive blood cultures for a single enteric microorganism, and all responded to antibiotics CONCLUSIONS: Our data do not suggest that liver-transplanted patients with choledochojejunostomy are more at risk of sepsis following liver biopsy, providing there is no "occult" biliary obstruction; therefore, they do not require prophylactic antibiotics as has been suggested by other authors. Mol Microbiol, 1996 Mar, 19(6), 1159 - 66 Stationary phase in Saccharomyces cerevisiae; Werner-Washburne M et al.; Like other microorganisms, the yeast Saccharomyces cerevisiae responds to starvation by arresting growth and entering stationary phase . Because most microorganisms exist under conditions of nutrient limitation, the ability to tolerate starvation is critical for survival . Molecular analyses have identified changes in transcription, translation, and protein modification in stationary-phase cells . At the level of translation, the pattern of newly synthesized proteins in stationary-phase cells is surprisingly similar to the pattern of proteins synthesized during exponential growth . When limited for different nutrients, yeast strains may not enter stationary phase but opt for pathways such as pseudohyphal growth . If nutrient limitation continues, the end-point is likely to be a stationary-phase cell . Based on the results of recent studies, we propose a model for entry into stationary phase in which G(o) arrest is separable from acquisition of the ability to survive long periods of time without added nutrients. Optom Vis Sci, 1996 Mar, 73(3), 201 - 3 Anterior hydrogel lens deposits: polished vs . unpolished surfaces; Kaplan EN et al.; Traditionally, lathe cut hydrogel lenses receive both back and front surface polishing to eliminate any surface irregularities that might serve as potential attachment sites for lens deposits or even microorganisms . However, with the advent of newer more technologically advanced lathing equipment, the need for lens polishing may require renewed justification . This study sought to compare, by scanning electron microscopy (SEM), anterior lens surface deposit formation on polished and unpolished 55% water hydrogel lenses . A total of 10 subjects wore in 1 eye (control) a lens with both front and back lens surfaces polished and on the other eye (test) a lens with only the back lens surface polished for a period of 2 weeks on a daily wear basis . Each lens was then scanned (using SEM), with 3 separate regions photographed at 30x using a 10 kV electron source . Using a Wilcoxon Signed-Ranks test on the differences between average deposit ratings for the polished and the unpolished lenses, by subject pair, we failed to reject the null hypothesis that the difference was zero. Biofizika, 1996 Mar-Apr, 41(2), 433 - 9 {Mechanisms of the combined effect of SHF electromagnetic radiation and hydrogen peroxide on the viability of microorganisms}; Kuchma TN et al.; The cellular (viability) and molecular (kinetics of changes in nucleoid viscosity) mechanisms of damage to various strains of microorganisms after single and combined action of SHF electromagnetic radiation and hydrogen peroxide are compared . The conditions are found in which marked synergetic interactions of the agents are realized . The role of repair systems in formation of final products of the interactions is discussed. Infect Control Hosp Epidemiol, 1996 Mar, 17(3), 193 - 200 The role of colonization in the pathogenesis of nosocomial infections; Bonten MJ et al.; The close relationship between colonization and the development of nosocomial infections has been demonstrated . Patient-related factors, such as underlying illness for all major sites of infection and advanced age, and pathogen-related factors, such as the ability of bacteria to adhere to epithelial cells, play the major roles in the pathogenesis of colonization . However, exact mechanisms of colonization have not been elucidated, and modulation of bacterial adherence as a method of infection prevention remains experimental . Current methods of infection prevention, therefore, focus either on preventing growth of colonizing microorganisms or on preventing patient-pathogen contact . Topical antibiotics have been used as a method of colonization prevention . However, their effectiveness may be limited by increases in antibiotic resistance; moreover, the effects of patient outcome are controversial . Maintenance of the physiologic mucosal environment using nonantimicrobial agents seems a promising approach, but only a few studies demonstrating efficacy have been published . Prevention of colonization still must rely heavily on basic infection control measures to prevent contact between patient and pathogen. Curr Microbiol, 1996 Mar, 32(3), 129 - 33 Quantitative determination of H2-utilizing acetogenic and sulfate-reducing bacteria and methanogenic archaea from digestive tract of different mammals; Morvan B et al.; Total number of bacteria, cellulolytic bacteria, and H2-utilizing microbial populations (methanogenic archaea, acetogenic and sulfate-reducing bacteria) were enumerated in fresh rumen samples from sheep, cattle, buffaloes, deer, llamas, and caecal samples from horses . Methanogens and sulfate reducers were found in all samples, whereas acetogenes were not detected in some samples of each animal . Archaea methanogens were the largest H2-utilizing populations in all animals, and a correlation was observed between the numbers of methanogens and those of cellulolytic microorganisms . Higher counts of acetogens were found in horses and llamas (1 x 10(4) and 4 x 10(4) cells ml-1 respectively). J Clin Immunol, 1996 Mar, 16(2), 90 - 6 Class I MHC presentation of exogenous antigens; Harding CV; Class I MHC (MHC-I) molecules present primarily endogenous antigens, i.e . antigens that are present in the cytosol and are subject to the cytosolic processing mechanisms that comprise the conventional MHC-I processing pathway . However, exogenous antigens can also be present by MHC-I molecules in certain circumstances, particularly in the case of particulate antigens . Recently, considerable attention has been focused on mechanisms that may contribute to alternate MHC-I processing pathways . Divergent results in several different systems have suggested that more than one alternate processing mechanism may exist . After phagocytic or endocytic uptake, some exogenous antigens can escape the vacuolar system and penetrate into the cytosol, accessing the conventional MHC-I antigen processing mechanisms . In other cases, MHC-I molecules present antigens that have no clear ability to actively escape the vacuolar system . Some results indicate that certain alternate processing mechanisms are quite distinct from the conventional MHC-I pathway and are not dependent on compartments, protein, or mechanisms that are necessary for the conventional pathway, including the endoplasmic reticulum, the transporter for antigen presentation (TAP) and proteasomes . In vivo, alternate MHC-I processing mechanisms may be expressed primarily by phagocytic antigen presenting cells, i.e., macrophages, and perhaps dendritic cells, although other cell types may contribute in certain circumstances . These mechanisms may play important roles in generating CD8 T cell responses, especially to antigens expressed by vacuolar microorganisms . In addition, they provide a potential avenue for therapeutic immunization to achieve protective CD8 T cell responses with nonviable vaccine preparations, in the absence of the endogenous antigen synthesis that is provided by live viral vaccine preparations. Radiats Biol Radioecol, 1996 Mar-Apr, 36(2), 264 - 9 {Effects of Co-60 gamma irradiation on sensitivity to UV light and photoreactivity of Escherichia coli Bs-1 bacteria}; Morozov II et al.; The reduction of photoreactivity and the change of UV-sensitivity of E . coli Bs-1 bacteria have been demonstrated after irradiation of cells with 60Co gamma-rays . The effect resulted from interaction of sub-damages induced by processes of ionization and excitation . The similar consequences can take place after irradiation of microorganisms with sparsely ionizing radiation of high energy. Burns, 1996 Mar, 22(2), 120 - 4 Experimental gut-derived endotoxaemia and bacteraemia are reduced by systemic administration of monoclonal anti-LPS antibodies; Gianotti L et al.; This study aimed to investigate the effects and mechanisms of action of systemic administration of monoclonal antibodies, anti-endotoxin (HA-1A), in an animal model of gut-origin sepsis . In the first experiment, Balb/c mice were transfused with allogeneic blood (C3H/HeJ mice) . Five days post-transfusion the animals were gavaged with 1 x 10(9) Escherichia coli and randomized into three groups (n = 22 each) to receive a sham burn (SB group) or a 20 per cent TBSA thermal injury, immediately followed by the systemic administration of monoclonal antibodies (3 mg/kg) (HA-1A group) or aliquots of sterile saline (Control group) . The animal survival rate was observed for 10 days postburn . In the second experiment transfusion and burn injury were reproduced but the mice (n = 8/group) were gavaged with 10(9) E.coli labelled with 111indium oxine . Four hours after the burn the mesenteric lymph nodes, liver, lungs and blood were harvested to determine plasma endotoxin levels and the magnitude of translocation of labelled bacteria measured by the residual radioactivity in the organs . Circulating endotoxin levels were determined by limulus assay . The mortality rate of the HA-1A group (9 per cent) was similar to the SB group (0 per cent) and significantly lower than the control group (59 per cent) (P < 0.05) . Both plasma endotoxin levels and degree of bacterial translocation in all extraintestinal tissues were significantly lower (by approximately 50 per cent) in the HA-1A group than in the control group (P < 0.05) . Systemic administration of HA-1A exerts a beneficial effect by reducing the circulating levels of endotoxin and by increasing the gut barrier function to translocating microorganisms. J Biol Chem, 1996 Mar 1, 271(9), 4581 - 4 A unique CD45 glycoform recognized by the serum mannan-binding protein in immature thymocytes; Uemura K et al.; The serum-mannan binding protein (S-MBP) is a calcium-dependent C-type lectin specific for mannose and N-acetylglucosamine . S-MBP is known as a host defense factor involved in innate immunity, where the target ligands for S-MBP should be on the surface of exogenous microorganisms . In this study, we tried to find endogenous ligands for this endogenous lectin . Among the cells tested, only the lymphocytes from thymus of BALB/c mice expressed ligands for S-MBP on their surface, those from bone marrow, spleen, mesenteric lymph nodes and peripheral blood all being negative . Interestingly, among the thymocytes, only the immature thymocytes with the CD4+CD8+CD3low phenotype expressed ligands for S-MBP, and ligands for S-MBP decreased on their maturation . A major cell surface glycoprotein bearing S-MBP ligands was isolated and identified as CD45RO, which is a transmembrane protein with tyrosine phosphatase activity . Deglycosylation experiments with N-glycanase and endoglycosidase H indicated that the S-MBP ligands on thymic CD45 are high mannose type or hybrid type N-linked oligosaccharides . This unique presentation of S-MBP ligands on this special CD45 isoform suggested the possibility that the oligosaccharide portion of CD45 on immature thymocytes is associated with the maturation, development or selection events of thymocytes. J Cell Biol, 1996 Mar, 132(6), 1037 - 52 Na+/H+ exchange activity during phagocytosis in human neutrophils: role of Fcgamma receptors and tyrosine kinases; Fukushima T et al.; In neutrophils, binding and phagocytosis facilitate subsequent intracellular killing of microorganisms . Activity of Na+/H+ exchangers (NHEs) participates in these events, especially in regulation of intracellular pH (pHi) by compensating for the H+ load generated by the respiratory burst . Despite the importance of these functions, comparatively little is known regarding the nature and regulation of NHE(s) in neutrophils . The purpose of this study was to identify which NHE(s) are expressed in neutrophils and to elucidate the mechanisms regulating their activity during phagocytosis . Exposure of cells to the phagocytic stimulus opsonized zymosan (OpZ) induced a transient cytosolic acidification followed by a prolonged alkalinization . The latter was inhibited in Na+-free medium and by amiloride analogues and therefore was due to activation of Na+/H+ exchange . Reverse transcriptase PCR and cDNA sequencing demonstrated that mRNA for the NHE-1 but not for NHE-2, 3, or 4 isoforms of the exchanger was expressed . Immunoblotting of purified plasma membranes with isoform-specific antibodies confirmed the presence of NHE-1 protein in neutrophils . Since phagocytosis involves Fcgamma (FcgammaR) and complement receptors such as CR3 (a beta2 integrin) which are linked to pathways involving alterations in intracellular {Ca2+}i and tyrosine phosphorylation, we studied these pathways in relation to activation of NHE-1 . Cross-linking of surface bound antibodies (mAb) directed against FcgammaRs (FcgammaRII > FcgammaRIII) but not beta2 integrins induced an amiloride-sensitive cytosolic alkalinization . However, anti-beta2 integrin mAb diminished OpZ-induced alkalinization suggesting that NHE-1 activation involved cooperation between integrins and FcgammaRs . The tyrosine kinase inhibitors genistein and herbimycin blocked cytosolic alkalinization after OpZ or FcgammaR cross-linking suggesting that tyrosine phosphorylation was involved in NHE-I activation . An increase in {Ca2+}i was not required for NHE-1 activation because neither removal of extracellular Ca2+ nor buffering of changes in {Ca2+}i inhibited alkalinization after OpZ or Fc-gammaR cross-linking . In summary, Fc-gammaRs and beta2 integrins cooperate in activation of NHE-1 in neutrophils during phagocytosis by a signaling pathway involving tyrosine phosphorylation. Dtsch Med Wochenschr, 1996 Feb 23, 121(8), 223 - 30 {Antibiotic prophylaxis using cefuroxime in bile duct endoscopy}; Lorenz R et al.; OBJECTIVE: To assess prospectively the effectiveness of a single prophylactic dose of cefuroxim before therapeutic endoscopy, in view of the general practice not to give antibiotics routinely . PATIENTS AND METHODS: In a prospective study endoscopic retrograde cholangiopancreatography (ERCP) or percutaneous transhepatic cholangiography with drainage (PTCD) together with simultaneous stone extraction, dilatation or stent implantation were performed in 99 patients (51 men, 48 women; mean age 60.6 +/- 19.2 years) . Group A (n = 49) received 1500 mg cefuroxim i.e . 30 min before the procedure, while none was given to group A patients (n = 50) . Several blood cultures were taken up to 60 min after the endoscopy . The number of septicaemias (bacteraemia with fever, rigor, circulatory reactions, leukocytosis or leukopenia) were noted . Bile cultures were obtained in 56 patients with indwelling biliary drainage . RESULTS: Incidence of bacteraemia was 6.1% (3 of 49) in group A, 16% (8 of 50) in group B, but this difference is not statistically significant . The septicaemia rate was 6.1% in group A and 10% in group B (not significant) . There were eleven positive blood cultures with 12 different microorganisms, Escherichia coli in four (A: n = 3) . In vitro cefuroxim sensitivity was 53.3% . 25 different bacterial species were isolated from 73.2% of bile cultures, of which 53.4% were sensitive to cefuroxim and 8.2% moderately so . CONCLUSION: Although the obtained differences between the two groups were not statistically different, the reduction in bacteraemia/septicaemia rate may be of clinical use . Further studies are needed with higher dosages or antibiotic combinations to improve these results. Biochim Biophys Acta, 1996 Feb 21, 1279(1), 49 - 57 Fluctuations in IR spectral parameters detected in mixed acyl chain membranes of Acholeplasma laidlawii B; Moore DJ et al.; Acholeplasma laidlawii B cells were grown at 37 degrees C on three binary C16:0-d(31)/C18:1 fatty acid mixtures at initial mol ratios of 3:2, 1:1, and 2:3 . These mol ratios produced final C16:0-d(31)/C18:1 lipid acyl chain mol ratios of 1.66 +/- 0.23 (n=6), 1.3 +/- 0.20 (n=6) and 0.58 +/- 0.09 (n=10), respectively, in the membrane of the microorganism . Membrane conformational order for the deuterated and proteated acyl chains in intact cells was monitored by FT-IR spectroscopy through the thermotropic response of the acyl chain CD2 and CH2 stretching frequencies . Intact cells and isolated membranes revealed broad phase transitions centered well below the growth temperature . This result differs from previous studies (Moore, D.J . and Mendelsohn, R . (1994) Biochemistry 33, 4080-4085) of cells grown on a single saturated fatty acid source, where Tm was close to the growth temperature . Fluctuations in IR spectral parameters from the liquid crystalline phases were detected in ten separate samples of cells grown on a 2:3 mixture (final mol ratio 0.58:1) of C16:0-d(31)/C18:1, and in no other cell preparation . These were manifest by reduced precision in the measurement of CH2 and CD2 stretching frequencies and are attributed to fluctuations in the membrane conformational order . In addition to conformational order fluctuations in intact cells, similar behavior was noted for the simple binary phosphatidylcholine (PC) mixture, DOPC/1-C16:0-d(31),2-C18:1 PC (2:1 molar ratio) . In this instance, the fluctuations were also detected through the temporal and thermotropic response of the relative intensity of the 1341 cm(-1) band assigned to end-gauche conformers about the penultimate C-C bond in the oleoyl chains . The relationship of these observations to the Raman spectroscopic detection of packing fluctuations in highly unsaturated PC's (Litman, B.J., Lewis, N., and Levin, I.W . (1991) Biochemistry 30, 313-319) is considered. FEBS Lett, 1996 Feb 19, 380(3), 263 - 6 Direct measurement of oscillatory generation of superoxide anions by single phagocytes; Isogai Y et al.; Phagocytic cells such as neutrophils generate superoxide anions (O2-) within phagocytic vacuoles for killing and digesting microorganisms . Here we report the simultaneous observation of morphological changes and O2- generation in single phagocytic cells during phagocytosis . Point stimulation of a cell by contact with an opsonized microelectrode at the cell surface induced significant deformation to engulf the electrode, and also induced the O2- generation which was measured by the electrode . Periodic fluctuations in the magnitude of the O2- generation were observed in the time course . These oscillations may be caused by metabolic regulation of the formation of NADPH, which is the substrate for the O2- generation Schweiz Med Wochenschr, 1996 Feb 17, 126(7), 246 - 54 {Molecular basis for detection of infectious agents}; Siegrist CA; Elimination of foreign pathogens requires detection of the presence of such microorganisms somewhere in the body . This task relies on specialized cells, among which specific lymphocytes permanently circulate throughout the body searching for signals indicative of the presence of invasive microorganisms . In contrast to B lymphocytes, T lymphocytes are unable to recognize bacteria or viruses in their native form . The structure of their antigen receptor only allows them to bind to small peptidic fragments that have to be stably presented by specific molecules at the surface of specific cells . These professional "antigen presenting cells" capture antigens and alert the immune system by expressing at their surface molecular complexes formed by their own major histocompatibility molecules (MHC) and fragments of the infectious agent . Extracellular microorganisms are captured by phagocytosis and digested into small peptides in the endosomal compartment of antigen presenting cells . The peptides able to bind to MHC class II molecules are transported to the cell surface . These antigen-MHC complexes are recognized by antigen specific CD4+ T lymphocytes, thus leading to the enhancement of antibody formation and of inflammatory responses which eliminate extracellular bacterial . In contrast, viruses or bacteria able to survive within the cytoplasm of the antigen presenting cells are digested by a specific multicatalytic enzymatic complex (the proteasome) . The antigenic peptides released into the cytosol will be transported into the endoplasmic reticulum by an active peptide pump . The peptides able to bind to the groove of MHC class I molecules are transported to the cell surface . Their recognition by specific cytotoxic CD8+ lymphocytes leads to the destruction of the cells identified as infected . Thus, the mechanisms of antigen processing and presentation are able to generate a wide variety of antigenic fragments . Depending on the initial extra- or intracellular localization of the microorganism, some antigenic peptides will appear on the surface of antigen presenting cells on either MHC class I or class II molecules which are specifically recognized by either CD4+ or CD8+ lymphocytes . Only the antigenic peptides that are generated by this process and able to bind to MHC molecules of antigen presenting cells will be recognized by circulating lymphocytes and thus induce antigen specific immune response . Their identification therefore forms the basis of the defense mechanisms against infectious diseases and of novel immunization strategies. Proc Natl Acad Sci U S A, 1996 Feb 6, 93(3), 1156 - 60 Hybrid restriction enzymes: zinc finger fusions to Fok I cleavage domain; Kim YG et al.; A long-term goal in the field of restriction-modification enzymes has been to generate restriction endonucleases with novel sequence specificities by mutating or engineering existing enzymes . This will avoid the increasingly arduous task of extensive screening of bacteria and other microorganisms for new enzymes . Here, we report the deliberate creation of novel site-specific endonucleases by linking two different zinc finger proteins to the cleavage domain of Fok I endonuclease . Both fusion proteins are active and under optimal conditions cleave DNA in a sequence-specific manner . Thus, the modular structure of Fok I endonuclease and the zinc finger motifs makes it possible to create "artificial" nucleases that will cut DNA near a predetermined site . This opens the way to generate many new enzymes with tailor-made sequence specificities desirable for various applications. Ugeskr Laeger, 1996 Feb 5, 158(6), 756 - 8 {Chlamydia trachomatis in pregnant women in the county of Vestsjaelland . Prevalence, prevention of perinatal transmission and cost-effectiveness of screening}; Ottesen M et al.; The prevalence of genital Chlamydia trachomatis (CT) in pregnant women and the perinatal transmission after treatment was investigated . An analysis of the cost-effectiveness of introducing a screening program among women at risk of having CT was made . Out of 339 pregnant women 2.9% had cervical CT . CT-positive women were treated with erythromycin . CT-positive women were significantly younger than CT-negative women and the odds ratio (OR) of having CT if nulliparous was 3.35 . The CT-prevalence was 6.6% among women younger than 25 years and 1.6% among women 25 years or older (p = 0.0163) . OR of having CT if younger than 25 years was 4.3 . The young women were significantly younger at sexual debut . None of the children of women treated for CT during pregnancy developed neonatal CT-conjunctivitis . The screening of women younger than 25 years was considered to be cost-effective . It is concluded that women younger than 25 years are at risk of having CT . Treatment of CT-positive women with erythromycin during pregnancy seems to be effective in eradicating this microorganism and thus preventing perinatal transmission and neonatal CT-conjunctivitis . It therefore seems rational to screen all pregnant women under the age of 25 years for cervical CT, especially in high risk areas. Gene, 1996 Feb 2, 168(1), 81 - 5 An Archaea 5S rRNA analog is stably expressed in Escherichia coli; Yang Y et al.; Mini-genes for 5S-like rRNA were constructed . These genes had a sequence which largely resembles that of the naturally occurring 5S rRNA of a bacterium, Halococcus morrhuae, which phylogenetically belongs to the Archaea . Plasmids carrying the mini-genes were transformed into Escherichia coli (Ec) . Ribosomal incorporation was not a prerequisite for stable accumulation of the RNA product . However, only those constructs with a well-base-paired helix I accumulated RNA product . This result strongly implies that this aspect of the structure is likely to be an important condition for stabilizing 5S rRNA-like products . The results are consistent with our current understanding of 5S rRNA processing in Ec . When used in conjunction with rRNA probe technology, the resulting chimeric RNA may be useful as a monitoring tool for genetically engineered microorganisms or naturally occurring organisms that are released into the environment. Biosci Biotechnol Biochem, 1996 Feb, 60(2), 235 - 7 Bioflocculant produced by Aspergillus sp . JS-42; Nam JS et al.; A bioflocculant from a fungus, Aspergillus sp . JS-42, was purified by precipitations with acetone and cetylpyridinium chloride . The flocculating activity was not significantly affected by pH from 3 to 8, but was stimulated by the addition of CaCl2, and was effective only when the reaction mixture contained an adequate amount of flocculant . The flocculant could efficiently flocculate all tested solids suspended in aqueous solution, including various microorganisms, organic acids, and inorganic materials. Pediatr Pulmonol, 1996 Feb, 21(2), 77 - 83 Short-term efficacy of ultrasonically nebulized hypertonic saline in cystic fibrosis; Eng PA et al.; Progressive lung disease in patients with cystic fibrosis (CF) is caused by thick secretions, which cause airway obstruction and subsequent colonization and infection by inhaled pathogenic microorganisms . Recently, recombinant human DNase has been shown to reduce the viscoelasticity of sputum in patients with cystic fibrosis and to improve lung function . Ultrasonically nebulized hypertonic saline (HS) has been demonstrated to enhance mucociliary clearance and sputum expectoration by rehydrating airway secretions, and may therefore provide a low cost alternative . We studied the changes in pulmonary function and symptoms in a group of patients with CF who have moderate to severe lung disease . The patients were evaluated following 2 weeks of treatment with HS in an open-label study . Subjects were randomly allocated to receive 10 ml of either 0.9% NaCl (IS) or 6% NaCl (HS) . Twice daily, prior to physiotherapy, treatments were delivered by a portable ultrasonic nebulizer . To prevent bronchoconstriction, 600 mg of salbutamol was administered prior to the nebulized solutions . A symptom score was recorded and spirometry was performed on day 0 before therapy was started, on day 14 (the last day of therapy), and on day 28 (14 days after the last treatment with either IS or HS) . Fifty-two patients (32 males), with a mean age of 16.2 (range 7-36) years completed the study . There was no difference in baseline characteristics between the two groups . Following 2 weeks of treatment, there was a significant improvement from baseline in FEV1 of 15.0 +/- 16.0% (mean +/- SD) in patients treated with HS, compared with a change of 2.8 +/- 13% in those on IS therapy (P = 0.004) . Furthermore, there was a subjective improvement in the effectiveness of chest physiotherapy as reported by those using HS (P = 0.02) . The treatment was well tolerated . We conclude that in patients with CF, ultrasonically nebulized hypertonic saline improves lung function in a way similar to that reported for human recombinant DNase when inhaled over a 2 week period . Nebulized saline also enhances the perception of effectiveness of chest physiotherapy. Nippon Rinsho, 1996 Feb, 54(2), 287 - 91 {Introduction of molecular biology in respiratory medicine and its perspective}; Kira S et al.; I reviewed the change of respiratory medicine in the past several decades, overlapping with my own history of medical training and clinical and research works . In the 1950's when I graduated from the medical school and internship, the tuberculosis had been conquered effectively by the development of new antituberculous agents and improvement of nutritional state in Japan . Fibroptic bronchoscopy was introduced in the respiratory medicine in 1968, and computed tomography, in the 1970's, which gave us a good insight into pathological and biological aspects of various lung diseases in vivo . Molecular biology was brought in the respiratory medicine and our laboratory in the last decade, and my colleagues used it for genetic study of hereditary diseases such as alpha-1 antitrypsin deficiency and protein C deficiency, biochemical analysis of lung cancer and other pulmonary diseases, rapid detection of microorganisms, and so on . In the next step, gene therapy will come true in the near future, and I hope many intractable diseases such as lung cancer and interstitial pneumonia will be cured by the new technology and scientific knowledge. Antimicrob Agents Chemother, 1996 Feb, 40(2), 464 - 7 Some repair-deficient mutants of Dictyostelium discoideum display enhanced susceptibilities to bleomycin; Deering RA et al.; Dictyostelium discoideum, a soil eukaryote, is highly resistant to DNA-damaging agents; repair mutants are more susceptible . Susceptibility to bleomycin, produced by Streptomyces verticillus, is greater for mutants which are susceptible to other agents than for resistant strains . The high potential for DNA repair may result from the need to cope with chemicals produced by other soil microorganisms. Trends Microbiol, 1996 Feb, 4(2), 53 - 9 Presentation of antigens derived from microorganisms residing in host-cell vacuoles; Ojcius DM et al.; Antigens presented by major histocompatibility complex molecules have been classified into those presented by 'endogenous' and 'exogenous' pathways . Some microorganisms reside within host-cell vacuoles that appear to avoid both pathways . Novel presentation mechanisms are being unraveled for these microorganisms, and their antigens, rather than being just peptides, can also consist of lipids or DNA fragments. Glycoconj J, 1996 Feb, 13(1), 19 - 26 O-linked protein glycosylation structure and function; Hounsell EF et al.; There has been a recent resurgence of interest in the post-translational modification of serine and threonine hydroxyl groups by glycosylation, because the resulting O-linked oligosaccharide chains tend to be clustered over short stretches of peptide and hence they can present multivalent carbohydrate antigenic or functional determinants for antibody recognition, mammalian cell adhesion and microorganism binding . Co-operativity can greatly increase the affinity of interactions with antibodies or carbohydrate binding proteins . Thus, in addition to their known importance in bearing tumour associated antigens in the gastrointestinal and respiratory tracts, glycoproteins with O-linked chains have been implicated as ligands or co-receptors for selectins (mammalian carbohydrate binding proteins) . Microorganisms may have adopted similar mechanisms for interactions with mammalian cells in infection, by having relatively low affinity ligands (adhesins) for carbohydrate binding, which may bind with higher affinity due to the multivalency of the host ligand and which are complemented by other virulence factors such as interactions with integrin-type molecules . In addition to specific adhesion signals from O-linked carbohydrate chains, multivalent O-glycosylation is involved in determining protein conformation and forming conjugate oligosaccharide-protein antigenic, and possible functional determinants. Anal Biochem, 1996 Feb 1, 234(1), 74 - 82 A continuous microtiter plate assay for screening nucleotide sugar-synthesizing nucleotidyltransferases; Ritter JE et al.; A continuous microtiter plate nucleotidyltransferase substrate screening assay (NUSSA) is described which allows the identification of nucleotide sugar-synthesizing enzyme activities . The assay is accomplished by the determination of the common product of these enzymes PPi with a PPi-dependent phosphofructokinase . A subsequent enzyme reaction cascade leads to the production of 2 mol NAD per mol PPi . PPi-dependent phosphofructokinase was purified from potato with respect to contaminating enzyme activities which would disturb NUSSA performance . NUSSA allows the quick, simultaneous, and comprehensive check of different sugar 1-phosphate and nucleoside triphosphate substrates using purified pyrophosphorylases or crude extracts of plants, microorganisms, and mammalian tissues . Moreover, NUSSA will assist to evaluate these enzymes for the synthesis of important nucleotide sugars which serve as substrates of glycosyltransferases in carbohydrate syntheses. Semin Liver Dis, 1996 Feb, 16(1), 65 - 82 Iron in liver diseases other than hemochromatosis; Bonkovsky HL et al.; There is growing evidence that normal or only mildly increased amounts of iron in the liver can be damaging, particularly when they are combined with other hepatotoxic factors such as alcohol, porphyrogenic drugs, or chronic viral hepatitis . Iron enhances the pathogenicity of microorganisms, adversely affects the function of macrophages and lymphocytes, and enhances fibrogenic pathways, all of which may increase hepatic injury due to iron itself or to iron and other factors . Iron may also be a co-carcinogen or promoter of hepatocellular carcinoma, even in patients without HC or cirrhosis . Based on this and other evidence, we hope that the era of indiscriminate iron supplementation will come to an end . Bloodletting, a therapy much in vogue 2 centuries ago, is deservedly enjoying a renaissance, based on our current understanding of the toxic effects of iron and the benefits of its depletion. Anaesthesist, 1996 Feb, 45(2), 113 - 30 {The role of polymorphonuclear neutrophilic leukocytes in the pathogenesis of acute respiratory distress syndrome (ARDS)}; Thiel M et al.; Polymorphonuclear leukocytes (PM-NL) constitute the first line of defence in the protection of the host from invading microorganisms . PMNL also contribute to the removal of cellular debris from necrotic tissues during reparative processes . For these purposes PMNL are armed with highly efficient bactericidal mechanisms which, under certain pathophysiological conditions, can be turned against the host himself . A vast body of evidence indicates that PMNL are able to cause lung injury which may be followed by the development of acute respiratory distress syndrome (ARDS) . Accordingly, in patients with ARDS blood concentrations of inflammatory activators of PMNL are elevated, cytotoxic mechanisms of PMNL are enhanced and sequestration of these cells has been demonstrated to be inversely proportional to gas exchange . The manifestation of ARDS in leukopenic patients, however, indicates the development of this clinical syndrome independently of the presence of PMNL . The ability to differentiate between PMNL-dependent and PMNL-independent pathways in the pathogenesis of this syndrome is not only of theoretical interest but also of therapeutic significance . Since the patient's systemic inflammatory response may vary according to the stage and type of the underlying disease, an exact qualitative and quantitative analysis of PMNL functions may provide the rationale for new anti-inflammatory drug regimens aimed at modifying the host's response without increasing the risk of infection. Shock, 1996 Feb, 5(2), 106 - 11 Effect of hemorrhagic shock and resuscitation upon hepatic phagocytic clearance and killing of circulating microorganisms; Kondo S et al.; We evaluated the effects of hemorrhagic shock/resuscitation (S/R) on hepatic reticuloendothelial system function, using an in vivo assay that discriminantly quantitates its two essential components, phagocytic clearance and phagocytic killing of double-labeled Escherichia coli injected intravenously . Rats were subjected to hemorrhagic shock at mean arterial pressure at 50 +/- 5 torr for 2 h, resuscitated, and survived . Hepatic phagocytic clearance was significantly decreased immediately following and 6 h after S/R, compared with sham-shocked rats, but recovered to normal levels after 24 h . Although hepatic killing efficiency was increased initially, and transiently depressed 6 h later, it was strikingly upregulated after 24 h . As a consequence, net hepatic killing was transiently suppressed at 0 and 6 h, but upregulated after 24 h . Pre-treatment with proinflammatory agonists, including endotoxin, IFN-gamma, or IFN-gamma + TNF-alpha enhanced both hepatic killing efficiency and net hepatic killing . These observations suggest that although hepatic killing function is initially impaired after the onset of S/R, it is strikingly upregulated 24 h later, simulating both the initial immunosuppression, and the later hyperinflammatory response to systemic S/R that could lead to multiple organ dysfunction syndrome. Scand J Work Environ Health, 1996 Feb, 22(1), 5 - 13 Health effects of indoor-air microorganisms; Husman T; The review provides a summary and discussion of current data on exposure to indoor-air microorganisms and their health effects, for example, respiratory irritation and nonspecific symptoms, respiratory infections, asthma and allergy, alveolitis and organic dust toxic syndrome, and chronic bronchitis, as well as a summary and discussion of the health effects of mycotoxins. Mol Cell Probes, 1996 Feb, 10(1), 15 - 22 Polymerase chain reaction for Mycoplasma hyopneumoniae detection in tracheobronchiolar washings from pigs; Blanchard B et al.; We have used the polymerase chain reaction (PCR) to detect Mycoplasma hyopneumoniae in tracheobronchiolar washings collected from experimentally infected piglets . On the basis of the published nucleotide sequence of M . hyopneumoniae I141 probe (accession number U02537), primers were chosen to produce an amplified fragment of 1561 bp . All the M . hyopneumoniae strains tested could be detected by the PCR test . DNA from other mycoplasmal and bacterial species currently isolated from respiratory tract of piglets gave negative result . The detection limit was estimated to be 500 fg of purified DNA corresponding to 4.10(2) organisms . The sensitivity of PCR reaction was also evaluated on microorganisms in culture, the limit sensitivity was 2.5 10(3) organisms . In the present study, a total of 143 tracheobronchiolar washings collected from experimentally infected piglets were submitted to PCR . For each tracheobronchiolar washing, PCR was performed on crude extracts treated with lysis buffer and on extracted DNA . The PCR results obtained with the two kinds of samples were compared to the immunofluorescence (IF) results . This comparison indicates a good correlation between PCR and IF test in 121/143 cases . The presence of M . hyopneumoniae is revealed in 19/143 of the washing samples only by PCR . In our hand, PCR appears to be the more sensitive test to detect M . hyopneumoniae in experimentally infected piglets. Intern Med, 1996 Feb, 35(2), 162 - 5 Tuberculous tenosynovitis in the elbow joint; Asaka T et al.; A 74-year-old woman was noted to have a mass lesion near the right elbow joint during medication for pulmonary tuberculosis . After discontinuation of medication, the mass gradually became enlarged with swelling and tenderness of the joint . Radiological evaluation disclosed tenosynovitis with an encapsulated abscess . Microscopic examination and culture of an aspiration biopsy specimen from the abscess showed no microorganisms . However, DNA extracted from the specimen contained mycobacterium tuberculosis DNA, permitting a diagnosis of tuberculous tenosynovitis . Mycobacterium is not always detected in biopsy specimens of tuberculous arthritis and tenosynovitis . In such cases, genetic diagnosis may be of great use. Int Immunol, 1996 Feb, 8(2), 221 - 30 Genetic complexity of the human hsp 60 gene; Pochon NA et al.; Hsp 60 is a chaperonin protein, homologous to GroEL of Escherichia coli and highly conserved across species . Immune response induced by the hsp 60 equivalent of numerous microorganisms elicits in animals and man a dominant cross-reactive T lymphocyte response . Hsp 60 has been strongly implicated as an example of molecular mimicry in the pathogenicity of autoimmune diseases and, more recently, in T cell-mediated protection . Curiously, in spite of this interest, the gene encoding HSP 60 has not yet been cloned . Sequencing of numerous PCR-derived HSP 60 clones . obtained following amplification of genomic DNA revealed multiple distinct but highly related sequences . These were all different from the sequence encoding the expressed protein and all had interrupted reading frames . PCR amplification from mRNA, however, yielded only the sequence expected for the expressed hsp 60 protein . This apparent paradox was resolved by cloning and sequencing HSP 60-specific genomic clones: the majority of these clones corresponded to intronless genes having the characteristics of retro-pseudogenes and were flanked by unrelated DNA sequences . In addition, several genomic clones were isolated that corresponded to a unique functional HSP 60 gene . This gene is composed of multiple exons, some very short . The transcription start site was identified and 750 bp of 5' flanking sequence were determined . The human HSP 60 gene is induced by heat . We conclude that hsp 60 is encoded by a single highly fragmented gene, that co-exists with multiple HSP 60 retro-pseudogenes, normally not expressed. Am J Respir Cell Mol Biol, 1996 Feb, 14(2), 155 - 60 Alveolar macrophage uptake of the environmental particulate titanium dioxide: role of surfactant components; Stringer B et al.; Pulmonary surfactant components can modulate uptake of microorganisms and viruses by alveolar macrophages (AMs), but little is known about their role in the uptake and clearance of inert environmental particulates . We tested the hypotheses that surfactant components {e.g., surfactant protein A (SpA) and the artificial bovine surfactant Survanta} modulate phagocytosis of inert environmental particulates by acting as particle opsonins, or by direct activation of AMs . AM uptake of a model inert particulate {titanium dioxide (TiO2)} was measured using flow cytometry to quantitate increased right angle scatter caused by particle uptake (e.g., fold increase in right angle scatter versus control: 2.6 +/- 0.3; and 5.0 +/- 0.2 for AMs plus TiO2, 20 and 80 micrograms/ml TiO2, respectively) . Opsonization of TiO2 with surfactant components resulted in a modest increase in AM uptake compared with that of unopsonized TiO2 {e.g., fold increase, uptake of TiO2 (50 micrograms/ml), opsonized with SpA, Survanta, and rat immunoglobulin G, respectively: 1.6 +/- 0.1; 1.3 +/- 0.01; 1.5 + 0.02, n = 3-4} . Uptake of inert latex beads was similarly enhanced after opsonizing with SpA and Survanta (beads per cell: unopsonized, 3.2 +/- 0.40; SpA, 5.0 +/- 0.55; Survanta, 6.0 +/- 0.12; n = 3-6) . Pretreating AMs with surfactant components and measuring the subsequent uptake of unopsonized TiO2 resulted in approximately the same magnitude of enhancement . The data indicate that surfactant components can increase AM phagocytosis of environmental particulates in vitro, but only slightly relative to the already avid AM uptake of unopsonized particles. J Exp Med, 1996 Feb 1, 183(2), 485 - 97 Selective development of T helper (Th)2 cells induced by continuous administration of low dose soluble proteins to normal and beta(2)-microglobulin-deficient BALB/c mice; Guery JC et al.; Continuous administration of soluble proteins, delivered over a 10-d period by a mini-osmotic pump implanted subcutaneously, induces a long-lasting inhibition of antigen-specific T cell proliferation in lymph node cells from BALB/c mice subsequently primed with antigen in adjuvant . The decreased T cell proliferative response is associated with a down-regulation of the T helper cell (Th)1 cytokines interleukin (IL)-2 and interferon (IFN)-gamma and with a strong increase in the secretion of the Th2 cytokines IL-4 and IL-5 by antigen specific CD4+ T cells . This is accompanied by predominant inhibition of antigen-specific antibody production of IgG2a and IgG2b, rather than IgG1 isotype . Interestingly, inhibition of Th1 and priming of Th2 cells is also induced in beta(2) microglobulin-deficient BALB/c mice, indicating that neither CD8+ nor CD4+ NK1.1+ T cells, respectively, are required . The polarization in Th2 cells is stably maintained by T cell lines, all composed of CD4+/CD8- cells expressing T cell receptor for antigen (TCR) alpha/beta chains, derived from BALB/c mice treated with continuous antigen administration, indicating that they originate from Th2 cells fully differentiated in vivo . This polarization is induced in BALB/c mice by continuous administration of any protein antigen tested, including soluble extracts from pathogenic microorganisms . Priming of Th2 cells is dose dependent and it is optimal for low rather than high doses of protein . Blocking endogenous IL-4 in vivo inhibits expansion of antigen-specific Th2 cells, but does not restore IFN-gamma production by T cells from mice treated with soluble antigen-specific Th2 cells, but does not restore IFN-gamma production by T cells from mice treated with soluble antigen, indicating the involvement of two independent mechanisms . Consistent with this, Th2 cell development, but not inhibition of Th1 cells, depends on non-major histocompatibility complex genetic predisposition, since the Th2 response is amplified in BALB/c as compared to DBA/2, C3H, or C57BL/6 mice whereas tested . These findings support the hypothesis that continuous release of low amounts of protein antigens from pathogenic microorganisms may polarize the immune response toward a Th2 phenotype in susceptible mouse strains. Appl Environ Microbiol, 1996 Feb, 62(2), 456 - 60 Fusarium polycaprolactone depolymerase is cutinase; Murphy CA et al.; Polycaprolactone (PCL), a synthetic polyester, is degraded by a variety of microorganisms, including some phytopathogens . Many phytopathogens secrete cutinase, a serine hydrolase that degrades cutin, the structural polymer of the plant cuticle . We compared wild-type strains and a cutinase-negative gene replacement mutant strain of Fusarium solani f . sp . pisi (D . J . Stahl and W . Schafer, Plant Cell 4:621-629, 1992) and a wild-type strain of Fusarium moniliforme to show that Fusarium cutinase is a PCL depolymerase . The wild-type strains, but not the mutant strain, (i) degraded PCL and used it as a source of carbon and energy, (ii) showed induction of secreted PCL depolymerase and an esterase activity of cutinase when grown in the presence of cutin, and (iii) showed induction of PCL depolymerase and an esterase activity of cutinase when grown in the presence of a hydrolysate of PCL, which contains PCL oligomers that are structurally similar to the natural inducers of cutinase . These results together with other details of regulation and conditions for optimal enzyme activity indicate that the Fusarium PCL depolymerase, required for degradation and utilization of PCL, is cutinase. Infect Immun, 1996 Feb, 64(2), 441 - 7 Mycoplasma arthritidis mitogen up-regulates human NK cell activity; D'Orazio JA et al.; While the effects of superantigens on T lymphocytes are well characterized, how superantigens interact with other immune cells is less clear . This report examines the effects of Mycoplasma arthritidis mitogen (MAM) on human natural killer (NK) cell activity . Incubation of peripheral blood mononuclear cells (PBMC) with MAM for 16 to 20 h augmented NK cytotoxicity (against K562) in a dose-dependent manner (P < or = 0.05) . Superantigen-dependent cellular cytotoxicity, an activity of superantigen-activated cytotoxic T cells, was not involved in lysis of K562 cells because the erythroleukemic tumor target cells expressed no class II major histocompatibility complex by fluorescence-activated cell sorter analysis . Kinetic experiments showed that the largest increase in NK activity induced by MAM occurred within 48 h . Incubation with MAM caused a portion of NK cells to become adherent to tissue culture flasks, a quality associated with activation, and augmented NK activity was found in both adherent and nonadherent subpopulations . Experiments using cytokine-specific neutralizing antibodies showed that interleukin-2 contributed to enhancement of the NK activity observed in superantigen-stimulated PBMC . Interestingly, MAM was able to augment NK lysis of highly purified NK (CD56+) cells in the absence of other immune cells in 9 of 12 blood specimens, with the augmented lytic activity ranging from 110 to 170% of unstimulated NK activity . In summary, data presented in this report show for the first time that MAM affects human NK cells directly by increasing their lytic capacity and indirectly in PBMC as a consequence of cytokines produced by T cells . Results of this work suggest that, in vivo, one consequence of interaction with superantigen-secreting microorganisms may be up-regulation of NK lytic activity . These findings may have clinical application as a means of generating augmented NK effector cells useful in the immunotherapy of parasitic infections or neoplasms. Infect Immun, 1996 Feb, 64(2), 422 - 7 Passive immunization with monoclonal antibodies against Porphyromonas gingivalis in patients with periodontitis; Booth V et al.; Selective inhibition of recolonization of Porphyromonas gingivalis was investigated by topical application of monoclonal antibody (MAb) . To select a MAb to P . gingivalis with the potential for recognizing most strains of P . gingivalis, we examined seven MAbs, one of which (MAb 61BG 1.3) recognized all 22 laboratory strains and serotypes of P . gingivalis tested as well as 105 human clinical isolates . A comparative study of the number of P . gingivalis bacteria identified by conventional culture and immunofluorescence with MAb 61BG 1.3 showed a very significant correlation between the two methods (Spearman r = 0.85, P < 0.001) . Fourteen patients with periodontitis, who harbored P . gingivalis in their subgingival plaque, were treated by root planing and with metronidazole to suppress any detectable P . gingivalis . In this double-blind study, the patients were then divided randomly into two groups; one was treated with MAb to P . gingivalis, and the other was treated with saline . Each patient had four subgingival applications of 3 micrograms of MAb (or saline) per tooth at 1, 3, 7, and 10 days after P . gingivalis was suppressed . The number of P . gingivalis bacteria was then monitored, and significantly less recolonization of the sites with the most severe periodontitis was found in the MAb-treated patients than in the control patients (P < 0.01) . This was evident at 6 and 9 months after the application of MAb, but by 12 months, P . gingivalis, was also found to recolonize these sites in two of the MAb-treated patients . The effect of MAb was specific to P . gingivalis, since the numbers of spirochetes were not significantly different between the two groups . However, no significant difference in any clinical periodontal indices between the immunized and control patients at 6 and 12 months was observed . This is the first demonstration that a putative periodontal pathogen can be selectively prevented from recolonization for up to 9 months in sites with the most severe periodontitis . This strategy could be used to establish directly in humans whether a microorganism is involved in the pathogenesis of periodontitis, by repeated application of the corresponding MAb at about 6-month intervals and by comparing the clinical indices between the MAb-treated and control patients. Ned Tijdschr Geneeskd, 1996 Jan 20, 140(3), 155 - 60 {3 emerging protozoal infections in The Netherlands: Cyclospora, Dientamoeba, and Microspora infections}; van Gool T et al.; Increased international travelling, an increased number of patients with immunosuppression caused by HIV infection, and renewed interest in known but little studied microorganisms, resulted in a more frequent finding of certain medically important parasites . Three emerging protozoal infection, Cyclospora cayetanensis, Dientamoeba fragilis and Microspora (Enterocytozoon bieneusi and Encephalitizoon) are causative agents of diarrhoea . Encephalitozoon infections are also associated with hepatitis, hepatoconjunctivitis and nephritis . C . cayetanensis infection was diagnosed in 28 patients in the years 1992-1995 in the Academic Medical Centre in Amsterdam, half of these patients returning from a visit to Indonesia . D . fragilis has a prevalence in the Netherlands of 8% among patients with diarrhoea lasting longer than one week referred for parasitological investigation . The prevalence of E . bieneusi in HIV positive patients with diarrhoea was 8-10% in the Academic Medical Centre in the last five years . Infection with Encephalitozoon appears to be endemic in the Netherlands. J Biol Chem, 1996 Jan 19, 271(3), 1455 - 61 Endogenous reactive oxygen intermediates activate tyrosine kinases in human neutrophils; Brumell JH et al.; In response to invading microorganisms, neutrophils produce large amounts of superoxide and other reactive oxygen intermediates (ROI) by assembly and activation of a multicomponent enzyme complex, the NADPH oxidase . While fulfilling a microbicidal role, ROI have also been postulated to serve as signaling molecules, because activation of the NADPH oxidase was found to be associated with increased tyrosine phosphorylation (Fialkow, L., Chan, C . K., Grinstein, S., and Downey, G.P . (1993) J . Biol . Chem . 268, 17131-17137) . The mechanism whereby ROI induces phosphotyrosine accumulation was investigated using electroporated neutrophils stimulated with guanosine 5'-O-3-thiotriphosphate in order to bypass membrane receptors . In vitro immune complex assays and immunoblotting were used to identify five tyrosine kinases present in human neutrophils . Of these, p56/59hck, p72syk, and p77btk were activated during production of ROI . Interestingly, the in vitro autophosphorylation activities of p53/56lyn and p59fgr were found to decline with ROI production . The mode of regulation of p56/59hck was explored in detail . Oxidizing agents were unable to activate p56/59hck in vitro and, once activated in situ, reducing agents failed to inactivate it, suggesting that the effects of ROI are indirect . Tyrosine phosphorylation of p56/59hck paralleled its activation, and dephosphorylation in vitro reversed the stimulation . We therefore conclude that tyrosine phosphorylation is central to the regulation of p56/59hck and likely also of p72syk, which is similarly phosphorylated upon activation of the oxidase . Because ROI have been shown to reduce the activity of tyrosine phosphatases, we suggest that this inhibition allows constitutively active kinases to auto/transphosphorylate on stimulatory tyrosine residues, leading to an increase in their catalytic activity . Enhanced phosphotyrosine accumulation would then result from the combined effects of increased phosphorylation with decreased dephosphorylation. Science, 1996 Jan 19, 271(5247), 348 - 50 C3d of complement as a molecular adjuvant: bridging innate and acquired immunity; Dempsey PW et al.; An optimal immune response should differentiate between harmful and innocuous antigens . Primitive systems of innate immunity, such as the complement system, may play a role in this distinction . When activated, the C3 component of complement attaches to potential antigens on microorganisms . To determine whether this alters acquired immune recognition, mice were immunized with a recombinant model antigen, hen egg lysozyme (HEL), fused to murine C3d . HEL bearing two and three copies of C3d was 1000- and 10,000-fold more immunogenic, respectively, than HEL alone . Thus, C3d is a molecular adjuvant of innate immunity that profoundly influences an acquired immune response. Anal Chem, 1996 Jan 15, 68(2), 271 - 80 Correction of mass spectral drift using artificial neural networks; Goodacre R et al.; For pyrolysis mass spectrometry (PyMS) to be used for the routine identification of microorganisms, for quantifying determinands in biological and biotechnological systems, and in the production of useful mass spectral libraries, it is paramount that newly acquired spectra be compared to those previously collected . Neural network and other multivariate calibration models have been used to relate mass spectra to the biological features of interest . As commonly observed, however, mass spectral fingerprints showed a lack of long-term reproducibility, due to instrumental drift in the mass spectrometer; when identical materials were analyzed by PyMS at dates from 4 to 20 months apart, neural network models produced at earlier times could not be used to give accurate estimates of determinand concentrations or bacterial identities . Neural networks, however, can be used to correct for pyrolysis mass spectrometer instrumental drift itself, so that neural network or other multivariate calibration models created using previously collected data can be used to give accurate estimates of determinand concentration or the nature of bacteria (or, indeed, other materials) from newly acquired pyrolysis mass spectra . This approach is not limited solely to pyrolysis mass spectrometry but is generally applicable to any analytical tool which is prone to instrumental drift, such as IR, ESR, NMR and other spectroscopies, and gas and liquid chromatography, as well as other types of mass spectrometry. Structure, 1996 Jan 15, 4(1), 97 - 107 Crystal structures of nucleoside 2-deoxyribosyltransferase in native and ligand-bound forms reveal architecture of the active site; Armstrong SR et al.; BACKGROUND: Nucleoside 2-deoxyribosyltransferase plays an important role in the salvage pathway of nucleotide metabolism in certain organisms, catalyzing the cleavage of beta-2'-deoxyribonucleosides and the subsequent transfer of the deoxyribosyl moiety to an acceptor purine or pyrimidine base . The kinetics describe a ping-pong-bi-bi pathway involving the formation of a covalent enzyme-deoxyribose intermediate . The enzyme is produced by a limited number of microorganisms and its functions have been exploited in its use as a biocatalyst to synthesize nucleoside analogs of therapeutic interest . RESULTS: We describe the crystal structure of the enzyme with and without bound ligand . The native structure was solved by the single isomorphous replacement with anomalous scattering method (SIRAS) and refined to 2.5 A resolution resulting in a crystallographic R factor of 16.6% . The enzyme comprises a single domain that belongs to the general class of doubly-wound alpha/beta proteins; it also exhibits a unique nucleoside-binding motif . X-ray analysis of enzyme-purine and enzyme-pyrimidine complexes presented here reveals that the active site lies in a cleft formed by the edge of the beta sheet and two alpha helices and contains side chains from two subunits . CONCLUSIONS: These results indicate residues that may be important in substrate binding and catalysis and thus may serve as a framework for elucidating the mechanism of enzyme activity . In particular, the proposed nucleophile, Glu98, lies in the nucleoside-binding pocket at an appropriate position for nucleophilic attack . A comparison of the enzyme interactions with both a purine and pyrimidine ligand provides some insight into the structural basis for enzyme specificity. Biochim Biophys Acta, 1996 Jan 12, 1278(1), 79 - 88 Contribution to the biophysics of the lethal effects of electric field on microorganisms; Kekez MM et al.; The proposed model assumes that the criteria leading to the lethal breakdown of microorganisms suspended in a continuous medium depend on two parameters: (a) the applied electric field must exceed the critical field of membrane to create holes and (b) the Joule energy (deposited in the membrane) must exceed the minimum value beyond which the cell can not recover . The first parameter initiates (reversible) breakdown and the second one, the completion of the (irreversible) electrical breakdown leading to death of the cell . The number of cells surviving the electric field treatment is related to statistical distribution of cell size . Comparison between theory and the experimental results of Kinosita and Tsong (1977); Hulsheger et al . (1980, 1981, 1983); Rosemberg and Korenstein (1990) and others is given. Science, 1996 Jan 12, 271(5246), 207 - 9 Protection against osmotic stress by cGMP-mediated myosin phosphorylation; Kuwayama H et al.; Conventional myosin functions universally as a generator of motive force in eukaryotic cells . Analysis of mutants of the microorganism Dictyostelium discoideum revealed that myosin also provides resistance against high external osmolarities . An osmo-induced increase of intracellular guanosine 3',5'-monophosphate was shown to mediate phosphorylation of three threonine residues on the myosin tail, which caused a relocalization of myosin required to resist osmotic stress . This redistribution of myosin allowed cells to adopt a spherical shape and may provide physical strength to withstand extensive cell shrinkage in high osmolarities. Ciba Found Symp, 1996, 202, 304 - 14; discussion 314-7 The transfer of viable microorganisms between planets; Davies PC; There is increasing acceptance that catastrophic cosmic impacts have played an important role in shaping the history of terrestrial life . Large asteroid and cometary impacts are also capable of displacing substantial quantities of planetary surface material into space . The discovery of Martian rocks on Earth suggests that viable microorganisms within such ejecta could be exchanged between planets . If this conjecture is correct, it will have profound implications for the origin and evolution of life in the solar system. Ciba Found Symp, 1996, 202, 40 - 52; discussion 52-60 Hydrothermal systems as environments for the emergence of life; Shock EL; Analysis of the chemical disequilibrium provided by the mixing of hydrothermal fluids and seawater in present-day systems indicates that organic synthesis from CO2 or carbonic acid is thermodynamically favoured in the conditions in which hyperthermophilic microorganisms are known to live . These organisms lower the Gibbs free energy of the chemical mixture by synthesizing many of the components of their cells . Primary productivity is enormous in hydrothermal systems because it depends only on catalysis of thermodynamically favourable, exergonic reactions . It follows that hydrothermal systems may be the most favourable environments for life on Earth . This fact makes hydrothermal systems logical candidates for the location of the emergence of life, a speculation that is supported by genetic evidence that modern hyperthermophilic organisms are closer to a common ancestor than any other forms of life . The presence of hydrothermal systems on the early Earth would correspond to the presence of liquid water . Evidence that hydrothermal systems existed early in the history of Mars raises the possibility that life may have emerged on Mars as well . Redox reactions between water and rock establish the potential for organic synthesis in and around hydrothermal systems . Therefore, the single most important parameter for modelling the geochemical emergence of life on the early Earth or Mars is the composition of the rock which hosts the hydrothermal system. Folia Microbiol (Praha), 1996, 41(2), 175 - 80 Spirochetal non-Borrelia-microorganism isolated from Ixodes ricinus; Schwarzova K et al.; Spirochetal microorganisms were isolated from female Ixodes ricinus in Slovakia . Morphological, immunochemical and molecular biological analysis showed that the microorganism shared several common antigens with Borrelia species while other genetic traits were distinct and not related to Borrelia burgdorferi sensu lato . Lyme disease patient's serum contained antibodies reacting with antigens of this microorganism . On the one hand the cross-reacting antigens represent a risk of false positive results in laboratory diagnostics, while on the other hand they have a certain potential for vaccine development against Lyme disease. Acta Gastroenterol Latinoam, 1996, 26(1), 39 - 43 Molecular pathogenesis of H . pylori disease; Go MF; H . pylori infection is a ubiquitous infection in man; it is associated with the development of various gastroduodenal disease manifestations . Numerous investigations are now seeking to elucidate the factors important in the microorganism that directly, or in concert with host and/or environmental factors, affect disease outcome . These studies involve the physiology and genetics of both the host and its pathogen, H . pylori. Folia Microbiol (Praha), 1996, 41(6), 465 - 72 Methionine production by microorganisms; Mondal S et al.; Microbial production of methionine is reviewed with 73 references . The review describes different methionine-producing organisms, as well as analog-resistant regulatory mutants, their optimum cultural conditions and yields . The pathways of methionine biosynthesis and their regulation are discussed. Acta Otolaryngol Suppl, 1996, 523, 98 - 100 The role of dendritic cells in the development of chronic tonsillar disease in children; Brodsky L et al.; Thirty-one children, 2.6-12.2 years (mean = 7.9 +/- 5.0) were divided into four clinical categories: normal controls (n = 7), recurrent tonsillitis (n = 8), idiopathic tonsillar hyperplasia (n = 9) and recurrent tonsillitis with hyperplasia (n = 7) . Immunohistopathologic studies were performed to determine the presence and location of HLA-DR, S-100 positive antigen presenting dendritic cells (DCs) in six microanatomic compartments: surface and crypt epithelium and submucosae, extrafollicular areas and lymphoid follicles . The results were analyzed in the context of the clinical history, bacteriology, and routine histopathology . The distribution of DCs was altered significantly with disease fewer numbers of DCs were found in the surface epithelium and greater numbers in the crypts and extrafollicular areas, than in normals, p <0.01 . The surface : crypt ratio of DCs was 1:1 for normal tonsils, but dropped to 1:3 in disease . Chronic cryptitis was more common in disease and correlated strongly to the presence of beta-lactamase producing microorganisms (R = 1.0) . An increased total bacterial concentration was correlated with increased numbers of DCs in the surface epithelium (R = 0.5, p <0.009) . In summary, the microanatomical distribution of DCs within the tonsil is significantly altered in disease . These alterations appear to be influenced by potentially pathogenic bacteria more often found in the crypts of abnormal tonsils. Acta Otolaryngol Suppl, 1996, 523, 101 - 4 Chronic tonsillitis in children: activation of polymorphonuclear cells from peripheral blood and tonsillar tissue . In vitro production of MPO, ECP and EPX; Mevio E et al.; Activation of polymorphonuclear cells (PMNs), neutrophils and eosinophils, occurs in response to infections . Myeloperoxidase (MPO) is an enzyme contained in neutrophils with toxic activity for many microorganisms including bacteria . Fosinophil cationic protein (ECP) and eosinophil X protein (EPX) are released by activated eosinophils in response to different inflammatory stimuli . Determination of serum levels of MPO, ECP and EPX permits assessment of the state of activation of these cells . The purpose of this study was to evaluate the state of activation of neutrophils and eosinophils present in tonsillar tissue and peripheral blood from 30 children (18 boys and 12 girls) undergoing tonsillectomy for chronic tonsillitis . For determination of serum levels of MPO, ECP and EPX, peripheral blood samples were obtained at the time of surgery: PMNs were separated by erythrosedimentation from peripheral blood and from tonsillar tissue after surgery and cultured for 7 days . The cells were plated (10(5) well) and the plates were incubated in 5% CO(2), 7% O(2), 80% N(2) . After 2, 24, 48, 72, 96, 120, 144 h, supernatants were removed from the cultures of both tonsillar tissue and peripheral blood PMNs for determination of in vitro release of MPO, ECP and EPX . The assays were carried out using a radioimmunotechnique (RIA, Pharmacia) and the concentrations of the three proteins (mean/6 wells) for each time were expressed in mu g/l . The data suggest activation of PMNs in children with chronic tonsillitis. Scand J Infect Dis, 1996, 28(6), 625 - 8 Lack of T-helper lymphocytes in BAL fluid from a HIV-negative patient with recurrent non-tuberculous mycobacterial lung infections; Heurlin N et al.; We describe here a previously healthy, 42 year old, HIV-negative woman . Following a seemingly successful 2-year antimycobacterial regimen for a lung infection caused by Mycobacterium avium/intracellulare she acquired a lung infection caused by M . chelonei . Characterization of alveolar cells from bronchoalveolar lavage fluid using flow cytometry revealed a total lack of T-cell subset CD4+ helper lymphocytes in spite of a normal proportion of the CD3+ and CD4+ T-cells in peripheral blood . The levels of Th2 cytokines such as IL-4, TGF-beta and G-CSF were higher in the patient's alveolar cells than in the cells of 4 healthy controls . This imbalance of cells and cell cytokines may contribute to the patient's susceptibility for non-tuberculous mycobacteria and her failure to eradicate these microorganisms. Bull Soc Pathol Exot, 1996, 89(4), 287 - 90 {A case of hemorrhagic rectocolitis associated with the presence of intestinal spirochetes}; Zerpa PR et al.; We report a case of a girl of 14 years old who developed a rapidly fatal chronic hemorrhagic rectocolitis . Several colonic biopsy specimens were studied by using the Vago stain . They showed many spirochetes attached end-to-end to the colonic epithelium . While the demonstration of a causal relationship between the intestinal symptoms and the presence of these spirochetes warrants further studies, the present observation outlines the need of researching this type of microorganisms through stains such as Vago stain whenever physicians are confronted with chronic intestinal inflammatory syndromes. Tsitologiia, 1996, 38(10), 1001 - 35 {The vacuolar apparatus and membrane fusion in the cell}; Bulychev AG et al.; Current literature on the structure of vacuolar apparatus and its involvement in the process of intracellular transport has been reviewed . Modern views on endocytosis and its particular steps are described . Special attention is paid to one of important steps of endocytosis-the phagosome-lysosome fusion, its disturbance under the action of pathogenic microorganisms, its inhibition and stimulation by some chemical factors and biologically active compounds . The authors widely used their own experimental data . Much attention is paid to the current notions on the fusion pore structure and function, as well as on fusion mechanisms of biological membranes and factors regulating this process. Stomatologiia (Mosk), 1996, 75(3), 15 - 8 {The significance of endocrine factors and microorganisms in the development of gingivitis in pregnant women}; Abraham-Inpijn L et al.; 40-100% of pregnant women suffer from the co-called pregnancy gingivitis . The cause of pregnancy gingivitis is possible multicausal: increased plasma female sex-hormones, alteration in dental plague and perhaps Prevotella intermedia in the subgingival plague, together with alteration of immunoresponse . Increasing levels of progesterone in the gingiva as well as estrogens due to specific receptors affect vascular permeability and exudation, provoke stasis of microcirculation, increase prostaglandine E2 formation in human gingiva . Decreased gingival keratinization and capability of cell regeneration may affect the epithelial barrier . This can perhaps explain the direct dependence between progesterone and estrogens increasing and the intensification of gingivitis clinical manifestation . The experimental gingivitis model of women during pregnancy and post-partum showed identical amounts of dental plague, but clinical manifestations were more intense during pregnancy and they had a relation with increasing P . Intermedia, no statistical significance was shown in the proportion of P . gingivalis . Increasing steroid hormones can substitute for the naphtoquinone requirement of P . intermedia . Optimal oral hygiene performed during pregnancy reduced gingival swelling, redness and bleeding tendency to levels which can be considered as physiologic for the pregnant state. Bull Soc Belge Ophtalmol, 1996, 260, 49 - 54 {Infectious corneal complications of contact lenses}; Houttequiet I; Keratitis in general may be caused by a large variety of microorganisms . The wear of contact lenses, mainly of soft material, increases the risk of corneal infection particularly by pseudomonas and acanthamoeba . The clinical aspects, the diagnostic procedures and the treatments are considered . With any type of lenses, rules of hygiene must be observed avoiding a brief tapwater rinse in order to decrease the risk of infection. Endeavour, 1996, 20(4), 150 - 6 Influence of microorganisms on the environmental fate of radionuclides; Gadd GM; Microorganisms have a significant influence on the environmental fate of radionuclides in aquatic and terrestrial ecosystems with a multiplicity of physico-chemical and biological mechanisms effecting changes in mobility and speciation . Physico-chemical mechanisms of removal include association with extracellular materials, metabolites and cell walls which are features of living and dead organisms . In living cells, some physico-chemical processes are reversible, influenced by metabolism and changing environmental conditions . Metabolism-dependent mechanisms of radionuclide immobilization include sulphide precipitation, transport and intracellular compartmentation and/or sequestration by proteins and peptides . In addition, chemical reduction to less soluble forms can result in immobilization . Microbial processes involved in radionuclide solubilization include autotrophic and heterotrophic leaching, and complexation by siderophores and other metabolites . Such mechanisms are important components of biogeochemical cycles for radionuclides and should be considered in any analyses of environmental radionuclide contamination . In addition, several microorganism-based biotechnologies are receiving interest as potential treatment methods. Mycopathologia, 1996, 134(3), 137 - 42 Effects of the infection of toxigenic fungi and an antagonistic Streptomyces strain on wheat spikes; Fulgueira CL et al.; The objective of the present study was to determine the effect on infection of wheat spikes by toxigenic fungi (Aspergillus parasiticus NRRL 2999, Fusarium tricinctum NRRL 3299, Fusarium graminearum CEREMIC 136/92) and a strain of Streptomyces sp . that is antagonistic to the above-mentioned fungi . Wheat grains (variety GRANERO INTA) were sown in 8 pots containing natural soil and kept in a greenhouse chamber . In the period of the early anthesis the wheat spikes were inoculated with conidial suspensions of each of the fungi in the presence or absence of Streptomyces . Each pot was assigned a different treatment . After an incubation of 100 days and when the wheat plants had attained maturity, the spikes were separated and the following items were determined: (a) number of grains obtained with each treatment, (b) weight of the grains, (c) average weight of the grains/treatment, (d) average number and weight of the grains/spike, and (e) invasion of the caryopses by the microorganisms determined by the analysis of the caryopses in seriate histological sections . There was a significant decrease (p < 0.01) in the average weight of the caryopses and in the weight and number of grains/spike in the presence F . graminearum . The wheat grains were invaded by of F . graminearum and A . parasiticus, an effect which was partially attenuated by the presence of antagonist Streptomyces sp . Nevertheless, the effect was not strong enough to prevent the degenerative consequences on the size and weight of the grains produced by F . graminearum. Crit Rev Biotechnol, 1996, 16(4), 301 - 29 Production of lactones and peroxisomal beta-oxidation in yeasts; Endrizzi A et al.; Among aroma compounds interesting for the food industry, lactones may be produced by biotechnological means using yeasts . These microorganisms are able to synthesize lactones de novo or by biotransformation of fatty acids with higher yields . Obtained lactone concentrations are compatible with industrial production, although detailed metabolic pathways have not been completely elucidated . The biotransformation of ricinoleic acid into gamma-decalactone is taken here as an example to better understand the uptake of hydroxy fatty acids by yeasts and the different pathways of fatty acid degradation . The localization of ricinoleic acid beta-oxidation in peroxisomes is demonstrated . Then the regulation of the biotransformation is described, particularly the induction of peroxisome proliferation and peroxisomal beta-oxidation and its regulation at the genome level . The nature of the biotransformation product is then discussed (4-hydroxydecanoic acid or gamma-decalactone), because the localization and the mechanisms of the lactonization are still not properly known . Lactone production may also be limited by the degradation of this aroma compound by the yeasts which produced it . Thus, different possible ways of modification and degradation of gamma-decalactone are described. Crit Rev Microbiol, 1996, 22(4), 279 - 93 The application of quantitative risk assessment to microbial food safety risks; Jaykus LA; Regulatory programs and guidelines for the control of foodborne microbial agents have existed in the U.S . for nearly 100 years . However, increased awareness of the scope and magnitude of foodborne disease, as well as the emergence of previously unrecognized human pathogens transmitted via the foodborne route, have prompted regulatory officials to consider new and improved strategies to reduce the health risks associated with pathogenic microorganisms in foods . Implementation of these proposed strategies will involve definitive costs for a finite level of risk reduction . While regulatory decisions regarding the management of foodborne disease risk have traditionally been done with the aid of the scientific community, a formal conceptual framework for the evaluation of health risks from pathogenic microorganisms in foods is warranted . Quantitative risk assessment (QRA), which is formally defined as the technical assessment of the nature and magnitude of a risk caused by a hazard, provides such a framework . Reproducing microorganisms in foods present a particular challenge to QRA because both their introduction and numbers may be affected by numerous factors within the food chain, with all of these factors representing significant stages in food production, handling, and consumption, in a farm-to-table type of approach . The process of QRA entails four designated phases: (1) hazard identification, (2) exposure assessment, (3) dose-response assessment, and (4) risk characterization . Specific analytical tools are available to accomplish the analyses required for each phase of the QRA . The purpose of this paper is to provide a description of the conceptual framework for quantitative microbial risk assessment within the standard description provided by the National Academy of Sciences (NAS) paradigm . Each of the sequential steps in QRA are discussed in detail, providing information on current applications, tools for conducting the analyses, and methodological and/or data limitations to date . Conclusions include a brief discussion of subsequent uncertainty and risk analysis methodologies, and a commentary on present and future applications of QRA in the management of the public health risks associated with the presence of pathogenic microorganisms in the food supply. Probl Tuberk, 1996, (5), 21 - 3 {Diagnosis and treatment of acute progressive tuberculosis types}; Khomenko AG et al.; An examination was made of 77 patients with extensive segmentary and lobular pulmonary tuberculous lesions: caseous pneumonia (n = 26), infiltrative caseous pneumonia (n = 18), fibrocavernous pneumonia complicated by caseous pneumonia (n = 16), and disseminated tuberculosis (n = 17) . All patients had destructive changes; in 82.7% of patients the caverns were large and great in size . Bacteria were isolated in 94.8%, mycobacterial drug resistance was noted in 51.8% . Four variants of the course of a disease were identified: 1) that with predominance of the intoxication syndrome (41.6%); 2) that with respiratory failure (24.7%); 3) that with pulmonary hemorrhage (15.6%), 4) that added by secondary microorganisms (18.2%) . Chemotherapy included a combination of 4 or 5 drugs along with pathogenetic tools, which stabilized a process in 80% of patients and arrested bacterial isolation in 69.5% . In 20%, the process continued to progress and in 3 of them died. Nephron, 1996, 74(4), 694 - 700 Effects of intraperitoneal antibiotics on human peritoneal mesothelial cell growth; Yen CJ et al.; Peritonitis is one of the most frequent complications of continuous ambulatory peritoneal dialysis (CAPD) . Necrosis and exfoliation of the mesothelial cell layer of the peritoneum develop during the acute phase of peritonitis . Agents that hamper regeneration of mesothelial cells will cause delayed recovery of the peritoneal surface, which results in continuous exposure of underlying stem cells to the stimulation of growth factors and possibly leads to peritoneal fibrosis syndrome . The aim of the present study is to determine the effects of several intraperitoneal antibiotics on human peritoneal mesothelial cell (HPMC) growth at their usual loading and maintenance doses . HPMCs were isolated from human omenta . Proliferation of HPMC was evaluated by modified methyltetrazolium assay and cell membrane integrity was assessed by lactate dehydrogenase method . The results showed that most cephalosporins exert an inhibitory, even toxic, effect on HPMCs at their loading doses . Cephalothin, cephradine, cefamandole, cefoxitin, cefuroxime and cefoperazone inhibited HPMC proliferation at their maintenance doses . Vancomycin, clindamycin, aztreonam, piperacillin, imipenem, tobramycin and ceftriaxone have no effect in their usual intraperitoneal doses . From the viewpoint of peritoneal protection, not only drug sensitivity of the causative microorganisms but also effects of antibiotics on HPMC regeneration should be considered when selecting antibiotics for CAPD peritonitis. Australas Biotechnol, 1996 Jan-Feb, 6(1), 8 - 12 Production of useful chemicals from sunflower oil by microbial biotransformation with rhizopus stolonifer NRRL 1478; El-Sharkawy SH; A number of microorganisms has been screened for growth on sunflower oil as a sole carbon source for production of useful chemicals . Rhizopus stolonifer NRRL 1478 was found to transform the lipid contents of sunflower oil into dodecyl b-D-glucopyranoside and dodecanedioic acid in 15 and 25% yields respectively . The produced compounds were isolated and purified by column chromatography and their chemical identities were established using MS, IR, 1H and 13C NMR spectroscopy. Przegl Epidemiol, 1996, 50(3), 245 - 51 {Ticks as a reservoir of Borrelia burgdorferi and Coxiella burnetii on Polish terrain}; Tylewska-Wierzbanowska S et al.; The aim of performed studies was to recognize the distribution of Coxiella burnetii and Borrelia burgdorferi infected ticks in Poland . The 1580 ticks infesting animals and humans were collected in different parts of the country . They belonged to Ixodes ricinus, Dermacentor reticulatus and Argas reflexus species . Presence of B burgdorferi and C . burnetii DNA in ticks has been sought with polymerase chain reaction test (PCR) . B . burgdorferi bacteria have been detected in 12 I . ricinus ticks (0.77%) . Infected ticks were collected in Koszalin, Krosno and Suwalki voivodships . C . burnetii bacteria were found in 3 ticks from Kielce and Tarnobrzeg voivodships (0.19%) . Obtained results indicate existence of natural reservoirs and vectors of C burnetii and B . burgdorferi in Poland . Since Q fever have not been recognized in central Poland until recently in can suggest diffusion of the C . burnetii reservoir to new regions . Presence of infected ticks in distant regions reflects wide distribution of these microorganisms all over the country. Biomed Mater Eng, 1996, 6(3), 173 - 89 Microrough surface of metallic biomaterials: a literature review; Wen X et al.; In this paper, four aspects of microrough surface of metallic biomaterials are reviewed: i.e., the preparation of microrough surface, the technology of surface roughness measurement, the parameters of roughness and the bio-effect of microrough surface . Microrough surfaces (roughness below 50 microns) are easily prepared and conveniently detected in practice . Microrough surfaces allow early better adhesion of mineral ions or atoms, biomolecules, and cells, form firmer fixation of bone or connective tissue, result in thinner tissue-reaction-layer with inflammatory cells decreased or absent, and prevent microorganism adhesion and plaque accumulation, when compared with the smooth surfaces. J Public Health Dent, 1996, 56(3 Spec No), 150 - 4; discussion 161-3 Dental caries under glass ionomer restorations; van Amerongen WE; The Atraumatic Restorative Treatment (ART) technique has two potential limitations . Because only hand instruments are used, dental caries can be left during cavity preparation . Beyond this limitation, the glass ionomer filling material currently used has some unfavorable mechanical properties with respect to its strength, wear resistance, and shrinkage during setting . The purpose of this paper is to provide an overview of changes that can be expected in carious dentin when a glass ionomer restoration is placed . Restriction of the substrate supply and the release of different components from the glass ionomer have an inhibiting effect on cariogenic microorganisms . Whether this influence is sufficient to completely arrest the caries process is doubtful . The influence of glass ionomers on the remineralization of carious dentin needs further research. Eur J Surg Suppl, 1996, (576), 59 - 60 Duration of antibiotic treatment in surgical infections of the abdomen . Blunt abdominal trauma; Melcher GA et al.; Blunt abdominal trauma is associated with a low risk of injury to the microorganism-containing hollow viscera . Therefore, routine pre-operative administration of antibiotics is not necessary . Antibiotics are given intraoperatively, if laparotomy discloses transmural injury of a hollow organ and peritoneal contamination . If intervention is early (< 12 hours) and there is no evidence of purulent exudate in the abdominal cavity, the antibiotic should be considered prophylactic and not exceed one dose . Neglected injuries should be treated with antibiotics for a maximum of 5 days. Eur J Surg Suppl, 1996, (576), 47 - 8; discussion 49 SIRS, MODS and tertiary peritonitis; Reemst PH et al.; Some patients with peritonitis develop a septic response without a detectable infective focus . It is suggested that an immunological dysfunction is responsible for this so called tertiary peritonitis . The role of the gastrointestinal tract in the development of multiple organ dysfunction syndrome (MODS) is discussed . In patients with tertiary peritonitis treatment should be directed towards restoration of the immunological balance, which is probably more important than the elimination of microorganisms with antibiotics. Eur J Surg Suppl, 1996, (576), 13 - 5 Duration of antibiotic treatment in surgical infections of the abdomen . At what point is infection cured but inflammation persists? Pollock AV. While infection is a consequence of invasion of microorganisms, sepsis is a phenomenon of the host . Systemic inflammatory response syndrome (SIRS), "severe sepsis", and "septic shock" may occur without infection, or persist, and lead to multiple organ dysfunction syndrome (MODS) after infection has been eradicated with antibiotics and surgery . The mechanisms responsible for these phenomena are increasingly being elucidated, but we cannot yet define when infective sepsis merges into non-infective sepsis . What do we know is they are just as lethal as each other. Annu Rev Microbiol, 1996, 50, 183 - 212 Microbial hydrolysis of polysaccharides; Warren RA; Microorganisms are efficient degraders of starch, chitin, and the polysaccharides in plant cell walls . Attempts to purify hydrolases led to the realization that a microorganism may produce a multiplicity of enzymes, referred to as a system, for the efficient utilization of a polysaccharide . In order to fully characterize a particular enzyme, it must be obtained free of the other components of a system . Quite often, this proves to be very difficult because of the complexity of a system . This realization led to the cloning of the genes encoding them as an approach to eliminating other components . More than 400 such genes have been cloned and sequenced, and the enzymes they encode have been grouped into more than 50 families of related amino acid sequences . The enzyme systems revealed in this manner are complex on two quite different levels . First, many of the individual enzymes are complex, as they are modular proteins comprising one or more catalytic domains linked to ancillary domains that often include one or more substrate-binding domains . Second, the systems are complex, comprising from a few to 20 or more enzymes, all of which hydrolyze a particular substrate . Systems for the hydrolysis of plant cell walls usually contain more components than systems for the hydrolysis of starch and chitin because the cell walls contain several polysaccharides . In general, the systems produced by different microorganisms for the hydrolysis of a particular polysaccharide comprise similar enzymes from the same families. Semin Gastrointest Dis, 1996 Jan, 7(1), 12 - 8 New approaches to mucosal immunization; Langermann S; An ideal vaccine ought to produce long-term protective immune responses against a pathogen . These responses include humoral antibodies, which neutralize invasive microorganisms, and cytotoxic T cells, which destroy intracellular pathogens . Both types of responses can be induced by parenteral immunization, which is how most vaccines have been administered to date . Given that most bacteria and viruses initiate infections at mucosal surfaces where secretory immunoglobulin A (sIgA) antibodies are thought to play an important role in prevention of microbial attachment and colonization, there may be an added advantage for vaccines that stimulate long-lasting secretory immunity against pathogens as well . A prerequisite for the generation of sIgA antibodies is that antigens be delivered at mucosal sites . This review focuses on novel mucosal vaccination strategies aimed at inducing such secretory immunity to pathogens, while at the same time, stimulating humoral and, in some cases, cellular immunity. Int Rev Cytol, 1996, 165, 1 - 52 Salt tolerance in plants and microorganisms: toxicity targets and defense responses; Serrano R; Salt tolerance of crops could be improved by genetic engineering if basic questions on mechanisms of salt toxicity and defense responses could be solved at the molecular level . Mutant plants accumulating proline and transgenic plants engineered to accumulate mannitol or fructans exhibit improved salt tolerance . A target of salt toxicity has been identified in Saccharomyces cerevisiae: it is a sodium-sensitive nucleotidase involved in sulfate activation and encoded by the HAL2 gene . The major sodium-extrusion system of S . cerevisiae is a P-ATPase encoded by the ENA1 gene . The regulatory system of ENA1 expression includes the protein phosphatase calcineurin and the product of the HAL3 gene . In Escherichia coli, the Na(+)-H+ antiporter encoded by the nhaA gene is essential for salt tolerance . No sodium transport system has been identified at the molecular level in plants . Ion transport at the vacuole is of crucial importance for salt accumulation in this compartment, a conspicuous feature of halophytic plants . The primary sensors of osmotic stress have been identified only in E . coli . In S . cerevisiae, a protein kinase cascade (the HOG pathway) mediates the osmotic induction of many, but not all, stress-responsive genes . In plants, the hormone abscisic acid mediates many stress responses and both a protein phosphatase and a transcription factor (encoded by the ABI1 and ABI3 genes, respectively) participate in its action. Skin Pharmacol, 1996, 9(4), 270 - 3 Influence of ion pairing on ex vivo penetration of erythromycin into sebaceous follicles; Matschiner S et al.; Microorganisms play an important role in the pathomechanism of acne vulgaris which is treated with antibiotics, particulary erythromycin (ERY) . The main problem in the topical use of ERY lies in achieving sufficient penetration of the drug into sebaceous follicles . Doubly enhanced penetration of an ion pair composed of ERY and octadecansulfonate (OS) in contrast to the commonly used ERY base was observed, using a multilayer membrane model (MMM) . The aim of the present study was to evaluate the results obtained on the MMM using excised human skin . The amount of ERY penetrating into sebaceous follicles of freshly excised human skin was measured using {N-methyl-14C}erythromycin . The ex vivo penetration of the ion pair ERY/OS into the sebaceous follicles was observed to be doubly enhanced compared with the penetration of the ERY base . The model was shown to be suitable for predicting in vivo penetration of anti-acne formulations into sebaceous glands. Adv Neuroimmunol, 1996, 6(2), 191 - 22 Molecular mechanisms of microglial activation; Zielasek J et al.; Microglial cells are brain macrophages which serve specific functions in the defense of the central nervous system (CNS) against microorganisms, the removal of tissue debris in neurodegenerative diseases or during normal development, and in autoimmune inflammatory disorders of the brain . In cultured microglial cells, several soluble inflammatory mediators such as cytokines and bacterial products like lipopolysaccharide (LPS) were demonstrated to induce a wide range of microglial activities, e.g . increased phagocytosis, chemotaxis, secretion of cytokines, activation of the respiratory burst and induction of nitric oxide synthase . Since heightened microglial activation was shown to play a role in the pathogenesis of experimental inflammatory CNS disorders, understanding the molecular mechanisms of microglial activation may lead to new treatment strategies for neurodegenerative disorders, multiple sclerosis and bacterial or viral infections of the nervous system. Adv Appl Microbiol, 1996, 42, 263 - 302 Phytase; Wodzinski RJ et al.; Of all the sources of phytase that have been studied (plant, animal, and microorganisms), the highest yields are produced by a wild-type strain A . niger NRRL 3135 (12.7 mg P/hr/ml = 6.8 microns P/ml/min = 113.9 nKat/ml) in a mineral salt medium in which total phosphate (4 mg %) is limiting for growth and cornstarch and glucose are the carbon sources . Synthesis of the enzyme is repressed by phosphate in the wild-type strain . Aspergillus niger NRRL 3135 produces two phytases one with pH optima at 2.5 and 5.5 (phyA) and one with an optimum at pH 2.0 (phyB) . It also produces a pH 6.0 optimum phosphatase that has no phytase activity . These three glycoproteins have been purified to homogeneity, characterized, sequenced, and cloned . The sequences have been compared to each other, other phytases, and to known phosphatases . Their homology has been determined . The active sites of phytases show remarkable homology to the active site residues of the members of a particular class of acid phosphatase (histidine phosphatase) . The most conserved sequence is RHGXRXP . Phytase has been covalently immobilized on Fractogel TSK HW-75 F and glutaraldehyde-activated silicate . It has been immobilized on agarose . Losses of activity have been noted on immobilization but these may be minimized by future research . It should be possible to commercially produce and recover penta-, tetra-, tri-, di-, and monoinositol phosphates using immobilized phytase if markets develop for those products . Phytase (phyA) from A . niger NRRL 3135 has been cloned into an A . niger glucoamylase producing strain CBS 513.88 using a construct that has a glucoamylae promoter and an A . niger NRRL 3135 leader sequence, and that is devoid of phosphate repression . The yield of the secreted enzyme was increased 52-fold above that of wild-type A . niger NRRL 3135 . The bioengineered organism produces 270 microns P/ml/min (4500 nKat/ml) which is approximately 7.9 g/liter in the medium . The yield of the secreted enzyme was increased 1440-fold above that of wild type CBS 513.88 . Commercial preparations of the cloned enzyme are available . Phytase (phyA) has been cloned into tobacco and canola . The enzyme is localized in the seed and expressed at high levels . Feeding of the seed to animals has made the phytin-P in the commercial diets available to the animals . The efficacy of feeding phytase to monogastric animals (poultry and swine) has been established . The amount of enzyme that is necessary to be added to commercial diets has been titred for broilers, layers, turkeys, ducks, and swine . The units of enzyme required are related to the phytin-P content in the diet . The use of the enzyme as a feed additive has been cleared in 22 countries . If phytase were used in the diets of all of the monogastric animals reared in the U.S., it would release phosphorus that has a value of $1.68 x 10(8) per year . The FDA has approved the enzyme preparation as GRAS . The effect of feeding phytase to animals enables assimilation of the P found in feed ingredients and diminishes the amount of phosphate in the manure and subsequently entering the environment . The effect of feeding phytase to animals on pollution has been quantitatively determined . If phytase were used in the diets of all of the monogastric animals reared in the United States, it would preclude 8.23 x 10(7) kg P from entering the environment. Scand J Thorac Cardiovasc Surg, 1996, 30(2), 83 - 6 Surgical treatment of acute infective endocarditis at Tartu University Hospital 1984-1993; Kuiv H et al.; Acute infective endocarditis was surgically treated in 42 patients (36 male, 6 female), aged 6-66 (mean 43.9) years . The causal microorganism was identified in 26 cases (61.9%) and the portal of entry in 12 . The main indication for surgery was cardiac failure . In 23 cases (54.7%) only the aortic valve was affected . The mean NYHA function class was 3.35 preoperatively and 1.85 postoperatively . All typical surgical findings were preoperatively recognized at echocardiography . Twenty-six ball-type and 16 tilting disk valves were inserted . The early mortality was 4.7% (2 cases), due to low cardiac output and bleeding . High early postoperative morbidity (23%), possibly resulted from too long interval from onset of disease to surgery, viz . 1-18 (mean 6.3) months . It is concluded that timely operation for acute infective endocarditis is effective. Int J Clin Lab Res, 1996, 26(2), 83 - 98 Development of Th 1- or Th 2-dominated immune responses: what about the polarizing signals? Romagnani S. Type 1 helper T cells and type 2 helper T cells represent two extremely polarized forms of the effector specific immune response, based on a distinctive profile of cytokine production . Type 1- and type 2 helper T cell-dominated immune responses play a different role in both protection and immunopathology . The differentiation of effector phenotypes depends on a complex matrix of interconnecting factors resulting from the evolutionary interplay between vertebrates and microorganisms . These include the physical form of the antigen, as well as the density and affinity of the peptide ligand, the cytokines produced by "natural" immunity cells at the time of antigen presentation, costimulatory signals provided by antigen-presenting cells, and hormones released into the microenvironment . The elucidation of genetic and environmental factors that regulate type 1 or type 2 helper T cell development in response to different antigenic stimulation is the basis for new immunotherapeutic strategies in allergic and autoimmune disorders, as well as for the improvement of vaccines. Oral Surg Oral Med Oral Pathol Oral Radiol Endod, 1996 Jan, 81(1), 38 - 43 Caries-related salivary microorganisms and salivary flow rate in bone marrow recipients; Dens F et al.; Cancer treatments often induce oral complications . In this study we investigate longitudinally the salivary gland function, the salivary caries-related microorganisms, and buffer capacity in bone marrow recipients . Stimulated saliva samples were taken midmorning . The salivary factors were studied in 42 patients from before transplant until 4 months after transplant . A dramatic reduction (66%) of salivary flow rate is noticed in all patients at 1 month after transplant, and only a partial recovery (42% reduction) is seen after 4 months . A clear shift toward a lower buffer capacity and a higher amount of cariogenic microorganisms is seen posttransplant . This shift is more pronounced when total body irradiation was included in the pretransplant conditioning therapy . These findings indicate that the studied parameters in transplant recipients can contribute to a higher caries risk and oral complications during the early posttransplant period. Parasitol Res, 1996, 82(6), 511 - 7 Mitotic activity of the hemocytes in the tick Ixodes ricinus (Acari; Ixodidae); Kuhn KH; The blood cells, or hemocytes, of Ixodes ricinus have been shown to recognize, attack, and phagocytose microorganisms invading the body cavity, or hemocoel, of this tick . Regulated proliferation and differentiation of hemocytes, also referred to as immunocytes, is basic to an effective immune response to invading microorganisms . Therefore, this study dealt with hemopoiesis in I . ricinus, the vector tick of the Lyme disease spirochete Borrelia burgdorferi . Histological evidence for the presence of hemopoietic tissue, a preferential proliferation site of hemocytes, is presented . Mainly the mitotic activity of free-floating hemocytes was examined . By means of microscopical photometry and flow cytometry, all three types of hemocytes in engorging female I . ricinus were found in different stages of the cell cycle . In the engorging tick, up to 40% of the hemocytes counted were in the S phase or the G2/M phase . From this study we conclude that the differentiated hemocyte types do not differentiate from stem cells in the adult tick . Moreover, microorganisms entering the hemocoel of engorging ticks are confronted with high numbers of hemocytes and, therefore, with an effective cellular immune response. Biosens Bioelectron, 1996, 11(11), 1139 - 45 Microbial biosensor for free fatty acids using an oxygen electrode based on thick film technology; Schmidt A et al.; A microbial biosensor based on thick film technology was developed . The microorganisms, Arthrobacter nicotianae, were immobilized in Ca-alginate directly on the electrode surface . For the stability of the calcium alginate gel the addition of 0.5 mM CaCl2 to the assay buffer was necessary . The respiratory activity of the microorganisms was monitored by oxygen consumption at -600 mV vs . Ag/AgCl reference electrode . The sensor was used in a batch system and was applied to the determination of free fatty acids in milk . Short-chain fatty acids (C4:0-C12:0) were the preferential substrates, with butyric acid being the main substrate . Consequently, the concentration of free short-chain fatty acids was represented as the butyric acid equivalent . The sensor showed linearity over the concentration range 9.5-165.5 microM (correlation coefficient, r = 0.99920) . The response time of the sensor was approximately 3 min . No additional dialysis membrane was necessary, which led to a high sensitivity of the sensor and fast response times . Recovery rates of 98-113% were found for butyric acid in milk samples using the sensor without any additional membrane and a sample dilution of 200 by the assay . Two widespread disadvantages of microbial sensors, long response times and long times to return to the baseline signal after use, could be overcome. J Ind Microbiol, 1996 Jan, 16(1), 36 - 41 Measurement of hydrocarbon-degrading microbial populations by a 96-well plate most-probable-number procedure; Haines JR et al.; A 96-well microtiter plate most-probable-number (MPN) procedure was developed to enumerate hydrocarbon-degrading microorganisms . The performance of this method, which uses number 2 fuel oil (F2) as the selective growth substrate and reduction of iodonitrotetrazolium violet (INT) to detect positive wells, was evaluated by comparison with an established 24-well microtiter plate MPN procedure (the Sheen Screen), which uses weathered North Slope crude oil as the selective substrate and detects positive wells by emulsification or dispersion of the oil . Both procedures gave similar estimates of the hydrocarbon-degrader population densities in several oil-degrading enrichment cultures and sand samples from a variety of coastal sites . Although several oils were effective substrates for the 96-well procedure, the combination of F2 with INT was best, because the color change associated with INT reduction was more easily detected in the small wells than was disruption of the crude oil slick . The method's accuracy was evaluated by comparing hydrocarbon-degrader MPNs with heterotrophic plate counts for several pure and mixed cultures . For some organisms, it seems likely that a single cell cannot initiate sufficient growth to produce a positive result . Thus, this and other hydrocarbon-degrader MPN procedures might underestimate the hydrocarbon-degrading population, even for culturable organisms. Chem Biol, 1996 Jan, 3(1), 7 - 11 How pathogens exploit interactions mediated by SH3 domains; Bliska J; An important event in signal transduction is the binding of SH3 domains, found in viral proteins such as v-Src and v-Crk, to proline-rich sequences . Recently, proline-rich proteins that bind host-cell SH3 domains have been identified in a variety of pathogenic microorganisms . Exploitation of SH3-mediated interactions by pathogens may be more common than previously suspected. Adv Exp Med Biol, 1996, 379, 141 - 5 Fluorescence decay of tryptophans in serine proteinases from microorganisms: relation to X-ray models; Genov N et al.; Fluorescence decay kinetics of indole groups in five proteinases from microorganisms are reported . The data show differences between the excited state lifetimes of the tryptophans located in identical positions in the polypeptide chains of the closely related proteinases mesentericopeptidase and subtilisin Novo . The lifetime of the single Trp 113 in subtilisins DY and Carlsberg are identical . The microenvironments of this residue in the four subtilisins are identical and probably its fluorescence is quenched in these proteins . The crystallographic models of the enzymes investigated were analysed in the region of the tryptophyl residues and provide an explanation for the observed emission properties. Scand J Infect Dis, 1996, 28(2), 195 - 6 Tuberculous meningitis in patients with nasopharyngeal carcinoma; Tang LM et al.; Mycobacterial infection has been recognized as a complication in patients with malignancy . Tuberculous (TB) meningitis has not been reported in patients with nasopharyngeal carcinoma (NPC); it may have been overlooked or confused with the underlying malignancy or meningitis caused by other microorganisms . We describe the occurrence of culture-proven TB meningitis in 2 NPC patients . The time lag between the diagnosis of NPC and the occurrence of TB meningitis was 4 years in 1 patient and 6 years in the other . In both patients, the diagnosis of TB meningitis was delayed; they were initially treated for bacterial meningitis . Subsequent antituberculous chemotherapy was successful in 1 patient but failed in the other . Recognition of the infection is important for early diagnosis and proper treatment of this potentially fatal condition in patients with NPC. Infect Agents Dis, 1996 Jan, 5(1), 36 - 46 Altered iron metabolism in HIV infection: mechanisms, possible consequences, and proposals for management; Boelaert JR et al.; The progression of human immunodeficiency virus (HIV) infection toward its more advanced stages is accompanied by increasing body iron stores . Iron accumulates in macrophages, microglia, endothelial cells, and myocytes . The iron burden is especially heavy in bone marrow, brain white matter, muscle, and liver . Excess iron potentially enhances oxidative stress, impairs several already compromised immune defense mechanisms, and directly promotes the growth of microbial cells . Thus, we hypothesize that the prevention (or at least, reduction) of iron loading might slow the progression of the infectious complications of HIV infection, and perhaps indirectly, the HIV infection itself . A twofold strategy is proposed, consisting of (a) limitation of iron intake through the alimentary, parenteral, and respiratory routes, and (b) possibly the use of iron chelator drugs that could decrease the iron burden, redistribute the metal to the erythroblasts, and suppress the growth of microorganisms . This approach is still to be considered as hypothetical . However, the available data suggest that there is an urgent need for careful clinical studies to clarify the role of iron status on the course of HIV infection. Rev Latinoam Microbiol, 1996 Jan-Mar, 38(1), 25 - 30 Assessment of viability of yeast by flow cytometry using Light Green as vital dye exclusion; Alvarado-Aleman FJ et al.; A comparative study of two different staining methods for estimation of yeast's viability is assessed by microbial flow cytometry . Propidium iodide (PI) a well known nucleic-acid binding vital dye exclusion is compared with light green (LG), a cytoplasmic function related vital dye widely used in histological, histochemical and immunocytochemical staining . The yeast model used was heat-killed Candida guilliermondii cells . The stained heat-killed bacterial population showed on the dot-plot flow cytometer analysis, a clear separation towards the green-orange (350-600 nm) for LG, and orange-red (550-725 nm) for PI on the fluorescence spectrum-zone channels . Both dyes showed by non-parametric Kolmcgorov-Smirnov, 99% of probability of difference between heat-killed and live microorganism's histogram-population, with a D = ranking from 0.50-0.64 for LG to 0.91-0.98 for PI . Higher cost and carcinogenic risk when handling PI, make LG a better choice for flow cytometry yeast viability tests. Postepy Hig Med Dosw, 1996, 50(1), 33 - 41 {Lactoferrin--its role in defense against infection and immunotropic properties}; Adamik B et al.; Lactoferrin (LF) is an iron-binding protein found in milk and other secretory fluids of mammals as well as in secondary granules of neutrophils . Receptors for LF were detected and isolated on activated T and B cells, monocytes, intestinal brush border cells, platelets and neoplastic cells . Very low physiologic serum levels of LF increase significantly upon infection . Serum concentration of LF is also elevated in rheumatoid patients . It is suggested that the ability of LF to bind an excess of Fe() ions, needed for growth of microorganisms and tumors, represents an important defence mechanism in humans . LF, in addition, may contribute to the protection against pathogens and their metabolites by enhancing phagocytosis, cell adherence and controlling release of proinflammatory cytokines such as IL-1, IL-6 and TNF-alpha . The protein diminishes also damaging effects of free radical release . LF possesses interesting immunotropic properties with regard to immature T and B cells by promoting phenotypic and functional maturation of these cells . LF also controls the effector phase of cellular immune response and inhibits manifestations of autoimmune response in mice . One molecular form of LF with a ribonuclease activity may have a prognostic value in breast cancer . Lactoferrin may be potentially applied in neutropenic patients or in patients with bleeding disorders as a preoperative immunomodulator. Int Rev Cytol, 1996, 167, 91 - 159 M cells in Peyer's patches of the intestine; Gebert A et al.; M cells are specialized epithelial cells of the mucosa-associated lymphoid tissues . A characteristic of M cells is that they transport antigens from the lumen to cells of the immune system, thereby initiating an immune response or tolerance . Soluble macromolecules, small particles, and also entire microorganisms are transported by M cells . The interactions of these substances with the M cell surface, their transcytosis, and the role of associated lymphoid cells are reviewed in detail . The ultrastructure and several immuno- and lectin-histochemical properties of M cells vary according to species and location along the intestine . We present updated reports on these variations, on identification markers, and on the origin and differentiation of M cells . The immunological significance of M cells and their functional relationship to lymphocytes and antigenpresenting cells are critically reviewed . The current knowledge on M cells in mucosa-associated lymphoid tissues outside the gut is briefly outlined . Clinical implications for drug deliver, infection, and vaccine development are discussed. Mycoses, 1996, 39 Suppl 1, 48 - 50 {Health risks in connection with fungi: a contribution to the assessment of fungi in the risk potential of safety provisions}; Meinhof W et al.; Fungi have been used for a long time in industrial production . Recent developments in biotechnology have lead to an increased awareness of possible health hazards connected with the use of microorganisms in industries . In order to avoid potential risks by appropriate protective measures it is necessary to assess the microorganisms, including fungi, with respect to their species-related risk potential . For this purpose, fungi were classified into three risk groups of which group I contains non-hazardous fungi and group III fungi with high risk . Most difficulties arise when it is to be decided if a fungus belongs to group I or group II which includes most pathogenic fungi . The present study was designed to provide data which facilitate the assessment of potentially hazardous fungi . It is based on the evaluation of the pertinent mycological literature as represented in the Review of Medical and Veterinary Mycology in the years from 1980 till 1989. Mycoses, 1996, 39 Suppl 1, 13 - 9 {Morphology of Malassezia-associated diseases}; Mittag H; Fine-structural investigations were done with surface material and slides of pityriasis versicolor, Malassezia-folliculitis and seborrheic eczema . Aspects of the microorganism Malassezia furfur, such as its presence, its distribution on the skin surface, and its shape, and changes in the host skin tissue, such as the structure of the horny layer and signs of an inflammation were registered . Two main types of Malassezia-associated dermatoses were defined . One type is characterized by a considerable number of microorganisms, adhering to regular cells of the horny layer (exemplified by pityriasis versicolor), the other type is characterized by signs of an inflammation and a very low number of visible fungal cells (exemplified by seborrheic eczema). Arch Tierernahr, 1996, 49(2), 151 - 7 Effect of pH on biohydrogenation of polyunsaturated fatty acids and their Ca-salts by rumen microorganisms in vitro; Van Nevel CJ et al.; The influence of different pH values on the protection of Ca-salts of polyunsaturated fatty acids (PUFA) against ruminal biohydrogenation was investigated . Ca-salts were prepared from soya bean oil fatty acids (SOH) and incubated in vitro with rumen fluid at different pH values . Biohydrogenation of Ca-salts of the PUFA's and their corresponding free fatty acids in SOH was compared . Two series of incubations were carried out, a first series with pH varying between 6.9 and 5.5, while in the second series, a narrower pH range was studied (6.8-6.3) . The experiments showed that between pH 6.9 and 6.3, Ca-salts of PUFA's are partly protected against biohydrogenation . Ca-salt of linoleic acid was protected to a greater extent than Ca-linolenate . Biohydrogenation of the salts is most probably due to dissociation of the solubilized Ca-salts . For efficient protection of Ca-salts of PUFA's against hydrogenation, maintenance of pH values above 6.3 will be necessary. Cancer Chemother Pharmacol, 1996, 38 Suppl, S99 - 102 Effect of interleukin 11 on normal and pathological thrombopoiesis; Teramura M et al.; Interleukin 11 (IL-11) is a stromal cell-derived cytokine that has multiple effects on hematopoietic and nonhematopoietic systems . In vitro, it enhances the growth of early progenitors and promotes megakaryocytopoiesis and erythropoiesis . In healthy animals, IL-11 administration stimulates megakaryocyte maturation and increases peripheral platelet counts . IL-11 accelerates the recovery of peripheral neutrophil, erythrocyte, and platelet counts in mice that have undergone cytoablative treatment . Therefore, IL-11 may be useful clinically as an agent promoting recovery from hematopoiesis . However, its clinical use in patients with hematological malignancies may be restricted because IL-11 has been reported to stimulate some leukemia and myeloma cells . In the United States, phase I trials have shown that IL-11 accelerates recovery from chemotherapy-induced or bone-marrow transplantation (BMT)-induced thrombocytopenia . In Japan, phase II trials studying the thrombopoietic effect of IL-11 in patients with solid tumors postchemotherapy, in patients undergoing BMT, and in patients with aplastic or refractory anemia are now under way . Recently, thrombopoietin (TPO) has been cloned, and its thrombopoietic effect and accelerating effect on platelet count recovery in thrombopoietic states have been demonstrated in animal models . The physiological effect of TPO is restricted to hematopoiesis; therefore, it may have fewer side effects than IL-11 . However, in addition to its hematopoietic effect, IL-11 administration to mice that have undergone cytoablative therapy significantly decreases morbidity and mortality due to chemotherapy-related endogenous infections caused by gut microorganisms . Therefore, IL-11 can be used in patients postchemotherapy and post-BMT not only to promote platelet recovery but also to prevent life-threatening infections . The use of in-vitro-expanded hematopoietic stem cells for BMT or as target cells for gene therapy is one of the most exciting areas in the field of medicine . Since IL-11 can expand hematopoietic progenitor-cell populations when used in combination with other cytokines, it may be useful as an ex vivo hematopoietic progenitor-cell-amplifying agent. EXS, 1996, 75, 87 - 102 Insect lysozymes; Hultmark D; Lysozymes, related to the chicken-type lysozymes in vertebrates, are ubiquitous components in the bacteriolytic armamentarium of insects . The enzyme is normally present in the blood, and together with other bactericidal factors lysozyme is often strongly induced when the insect is infected . This response is regulated by mechanisms that are related to those that activate inflammatory, acute-phase and immune responses in mammals, and the induction of lysozyme and other factors is now being investigated as a model for innate immune reactions in general . A special adaptation is seen in flies like Musca and Drosophila . These animals live on the microorganisms in decompositing matter, and they have developed a specialized set of lysozymes that are expressed in the alimentary tract . In Drosophila, at least seven different lysozyme genes are clustered in a small region on the third chromosome . The different genes are expressed in different parts of the digestive tract, and at different time points during development, and they are highly divergent in sequence . The major lysozymes in the fly gut have acidic isoelectric points and/or pH optima, and their evolution provides an interesting parallel to the ruminants. Lijec Vjesn, 1996 Jan-Feb, 118(1-2), 23 - 6 {Fatal "overwhelming" strongyloidiasis in an immunosuppressed patient}; Bozikov V et al.; The increased use of immunosuppressants in the treatment of malignant and non-malignant diseases in today's medicine has significantly contributed to the increased interest in infections caused by opportunistic microorganisms and rare parasites . A fifty-eight-year old male patient, professor, born in Bosnia, was admitted to the Institute due to poor general condition and decompensated steroid diabetes . He had been under immunosuppressant therapy for the previous 5 weeks . Six months before, he noticed squamous and crusted changes on capilli, and afterwards on his body too . As these changes did not respond to local therapy he was admitted to the Department of Dermatovenereology, Zagreb University School of Medicine . Histologic analysis indicated pemphigus erythematosus . He was treated with immunosuppressants (methylprednisolone + azathioprine) . Endoscopic examinations revealed duodenal ulcer, in addition to diabetes which could not be regulated by oral hypoglycemics . He received antiulcerative therapy for ulcer treatment . Several hours upon admission the patient became highly febrile, and vomited a sanguinolent content . In spite of intensive therapy, he became comatose and died 20 hours later . On autopsy, generalized strongyloidosis of the lungs, liver, duodenum and small intestine, and a bleeding duodenal ulcer due to strongyloidosis were found . This review should remind us that hyperinfestation with strongyloides is a rare and severe complication, and could be expected in immunocompromised patients. Prog Drug Res, 1996, 46, 9 - 42 Endogenous sodium pump inhibition: current status and therapeutic opportunities; Hollenberg NK et al.; One might ask, given the number of false trails that have been pursued, why we, and so many others, have continued to pursue the elusive digitalis-like factor? The answer can be found in the many review articles cited above {4-13} . In animal models of volume-dependent hypertension, evidence favoring sodium pump inhibition as at least a contributing factor, is essentially overwhelming . These observations are supported by multiple lines of less direct evidence in humans which are also compatible with a contribution of a circulating sodium pump inhibitor . Indeed, if multiple premature claims announcing the isolation of the digitalis-like factor had not appeared, this would be one of a large number of interesting scientific areas in which identification of a responsible vector was expected momentarily . The disenchantment so often expressed, we believe, reflects a response to those premature claims . We echo a recent review on the digoxin-like sodium pump inhibitor story from one of the productive groups in this area . "Now that there is little doubt that endogenous digoxin-like inhibitors of sodium transport exist..., the link between these substances, salt intake and vascular tone must be pursued with increasing vigor" {12} . That pursuit, of course, will be easier if the criteria concerning the responsible mediator are employed systematically . Because the current situation resembles so strikingly the situation late in the nineteenth century--when efforts focused on the attempt to identify a specific microorganism as the agent responsible for specific disease--we employed Koch's Postulates as the organizing principle . The challenge faced by Robert Koch over a century ago is identical to the challenge that those of us who are interested in digitalis-like factors face today . Passionate advocacy and equally impassioned denial can be seen as a stage in the scientific process when the problem is important and has proven to be more intractable than anticipated . Substantial, but still circumstantial evidence supports strongly a role for a circulating digitalis-like factor not only in normal sodium homeostasis and in the pathogenesis of salt-sensitive hypertension, but also in the pathogenesis of a wide array of processes that have an uncertain etiology . Although supported by many lines of evidence, this intriguing concept remains controversial, in large part because the responsible factor has proven to be very elusive . Informed opinion today ranges from arguments that the agent does not exist to contrary arguments that the agent has been identified . A very large number of candidates from a wide range of chemical classes have been proposed . Indeed, the large number of candidates, none supported by absolutely definitive evidence, has contributed to the controversy . In this essay, we have attempted to define and illustrate the information that will be required before a candidate becomes widely accepted. J Clin Microbiol, 1996 Jan, 34(1), 34 - 7 Clinical comparison of isolator, Septi-Chek, nonvented tryptic soy broth, and direct agar plating combined with thioglycolate broth for diagnosing spontaneous bacterial peritonitis; Hay JE et al.; Spontaneous bacterial peritonitis is a life-threatening complication of cirrhotic ascites . Optimal patient management depends on the isolation of the causal organism from ascitic fluid . To evaluate culture techniques for the diagnosis of spontaneous bacterial peritonitis, we prospectively compared three blood culture system, the Isolator system, a lysis-centrifugation system, the Septi-Chek system, a biphasic culture system, and a nonvented tryptic soy broth system, all inoculated at the bedside, and our standard method of direct inoculation of specimens after transport to the laboratory onto agar plates and into thioglycolate broth . The results showed that the Septi-Chek and nonvented tryptic soy broth systems each recovered statistically significantly more pathogens than either the Isolator system (P = 0.0084) or the standard method (P = 0.00098) . The Isolator system recovered more pathogens than the standard plate method, but this difference was not statistically significant . Both the Isolator system and the standard plate method recovered more contaminating microorganisms than the Septi-Chek or nonvented tryptic soy broth system . The Isolator system required the most processing time compared with the processing times required by any other method. Crit Rev Food Sci Nutr, 1996 Jan, 36(1-2), 123 - 73 The polymerase chain reaction: applications for the detection of foodborne pathogens; Hill WE; Faster methods for the detection of foodborne microbial pathogens are needed . The polymerase chain reaction (PCR) can amplify specific segments of DNA and is used to detect and identify bacterial genes responsible for causing diseases in humans . The major features and requirements for the PCR are described along with a number of important variations . A considerable number of PCR-based assays have been developed, but they have been applied most often to clinical and environmental samples and more rarely for the detection of foodborne microorganisms . Much of the difficulty in implementing PCR for the analysis of food samples lies in the problems encountered during the preparation of template DNAs from food matrices; a variety of approaches and considerations are examined . PCR methods developed for the detection and identification of particular bacteria, viruses, and parasites found in foods are described and discussed, and the major features of these reactions are summarizedPublication Types:
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