Pharmacol Toxicol, 1997 May, 80(5), 246 - 50 Bioavailability of enrofloxacin after oral administration to fed and fasted pigs; Nielsen P et al.; The disposition of enrofloxacin was measured after intravenous and oral administration to pigs . Eight clinically healthy pigs weighing 25 to 40 kg received a dose of 5 mg/kg intravenously and 10 mg/kg orally in both a fasted and a fed condition in a three-way cross-over design . Enrofloxacin was present in plasma for up to 72 hr after both intravenous and oral administration to fasted as well as fed pigs . The steady state volume of distribution was determined to 3.9 +/- 0.5 1/kg body weight which indicates that enrofloxacin was widely distributed in the body . The bioavailability was determined to 83 +/- 13% in fed and to 101 +/- 32% in fasted pigs . Based on the bioavailability and the resulting plasma concentrations it is concluded that a therapeutically active concentration for the most common porcine microbial pathogens are maintained for at least 24 hr after oral administration of 10 mg/kg body weight to fasted as well as to fed pigs . Ciprofloxacin which is an active metabolite of enrofloxacin was observed in plasma samples from all treated pigs, but the concentration never exceeded 0.1 microgram/ml . During the first 24 hr after the administration of enrofloxacin the concentration of the metabolite made up less than 10% of the corresponding concentration of the parent compound. Biosci Biotechnol Biochem, 1997 May, 61(5), 830 - 5 High-level expression of the chemically synthesized gene for microbial transglutaminase from Streptoverticillium in Escherichia coli; Kawai M et al.; We developed a novel approach for the high-level production of a microbial transglutaminase (TGase) from Streptoverticillium in E . coli . The direct expression of the TGase gene in E . coli cells did not cause overproduction, probably due to the harmful influence of TGase activity, which introduces covalent crosslinks between proteins . Therefore, we fused the chemically synthesized TGase gene coding for the entire 331 amino acid residues at the amino terminus to a bacteriophage T7 gene 10 leader peptide (260 amino acids) using an inducible expression vector . The TGase gene was expressed as inclusion bodies in the E . coli cytoplasm . Restoring 15 amino acid residues upstream of the amino terminus of the mature TGase by a two-step deletion of the fusion sequence facilitated solubilization and subsequent proteolytic cleavage, thus releasing mature TGase . Although the mature form had less TGase activity than native TGase, because of the poor refolding rate, these results suggest that this system is suitable for the efficient production of TGase. Br J Nutr, 1997 May, 77(5), 745 - 56 The energy value of short-chain fatty acids infused into the caecum of pigs; Jorgensen H et al.; The present work was undertaken to study the energy value of a mixture of acetic, propionic and butyric acids (0.682:0.226:0.092) infused intracaecally in growing pigs . A basal diet low in fibre (42 g NSP/kg DM) was given at below the requirement for maximum weight gain . In six 2-week periods, N and energy balance measurements in eight growing pigs were carried out with and without infusion of short-chain fatty acids (SCFA) . Heat production was measured using open-circuit chambers and the concentration of SCFA in faeces was determined . Less than 1% of the infused SCFA was excreted in faeces illustrating the capacity of the hind-gut to absorb and metabolize SCFA . Infusion of SCFA did not affect the digestibility of nutrients and energy . However, N retention increased demonstrating that SCFA are an energy source for protein gain when pigs are fed at below the requirement of energy . Increased CH4 production together with an increased excretion of branched-chain fatty acids in faeces suggested that there was a higher microbial activity in the hind-gut during infusion . The partial utilization of the infused energy in SCFA was 0.821 . A small proportion of the infused energy in SCFA was retained in protein (0.099) and a considerable amount was retained as fat (0.722). J Hosp Infect, 1997 May, 36(1), 49 - 65 An evaluation of five protocols for surgical handwashing in relation to skin condition and microbial counts; Pereira LJ et al.; Five protocols for surgical handwashing (scrubbing) were evaluated for their efficiency of removal of micro-organisms and their drying effect on the skin . The scrubbing protocols tested were: (1) an initial scrub of 5 min and consecutive scrubs of 3.5 min with chlorhexidine gluconate 4% (CHG-5); (2) an initial scrub of 3 min and consecutive scrubs of 2.5 min with chlorhexidine gluconate 4% (CHG-3); (3) an initial scrub of 3 min and consecutive scrubs of 2.5 min with povidone iodine 5% and triclosan 1% (PI-3); (4) an initial scrub of 2 min with chlorhexidine gluconate 4% followed by a 30 s application of isopropanol 70% and chlorhexidine gluconate 0.5%, and a 30 s application of isopropanol 70% and chlorhexidine gluconate 0.5% for consecutive scrubs (IPA); and (5) an initial scrub of 2 min with chlorhexidine gluconate 4% followed by a 30 s application of ethanol 70% and chlorhexidine gluconate 0.5%, and a 30 s application of ethanol 70% and chlorhexidine gluconate 0.5% for consecutive scrubs (EA) . A convenience sample of 23 operating theatre nurses completed each scrub protocol for one week in a randomized order . A week of normal work activities intervened between each protocol . Subjects were assessed before commencing and after completing the week of each protocol to determine changes in the microbial counts and skin condition of the hands . Specimens for microbial analysis were collected before, immediately after and 2 h after an initial scrub, and 2 h after a consecutive scrub . The CHG-5, CHG-3 and PI-3 protocols, which used detergent-based antiseptics only, were compared with protocols incorporating an alcohol-based antiseptic (IPA and EA) . The protocols incorporating alcohol-based antiseptics and the CHG-5 protocol were generally associated with the lowest post-scrub numbers of colony forming units (cfu) . No difference between the CHG-5 protocol and the alcohol-based antiseptics was found at the beginning of the test week, but after exclusive use of the respective protocols for a week, the alcohol-based antiseptics were associated with significantly lower cfu numbers in two out of the three post-scrub samples (P = 0.003, P = 0.035) . Although virtually no statistically significant differences in skin condition were found, many subjects reported the alcohol-based antiseptic protocols to be less drying on the skin . The findings of this study support the proposition that a scrub protocol using alcohol-based antiseptics is as effective and no more damaging to skin than more time-consuming, conventional methods using detergent-based antiseptics. J Formos Med Assoc, 1997 May, 96(5), 336 - 45 Constitutive fatty acid and enzyme profiles of Mycobacterium species; Teng LJ et al.; Sixty-one strains of Mycobacterium tuberculosis complex and 47 strains of nontuberculous mycobacteria were analyzed for fatty acids and enzyme profiles . Cellular fatty acids were extracted from bacteria, methylated and analyzed by gas liquid chromatography operated either manually (Perkin-Elmer) or by the automatic Microbial Identification System . The major cellular fatty acids in all mycobacterial species were C16:0 and C18:1 . Tuberculostearic acid was found in all species with the exception of Mycobacterium gordonae . The fatty acids with a carbon-length longer than 20 could be detected only by conventional gas chromatography . Strains of M . tuberculosis had a high ratio of C26:0 to C24:0, and a relatively low ratio of C14:0 to C15:0 . For determination of branched-chain fatty acids, the MIS provided more definitive results . The data indicated that the fatty acid profiles could provide rapid species identification . The results of the enzyme profile analysis using API-ZYM strips showed 39 different patterns from 59 strains of M . tuberculosis, and 41 different patterns from 46 nontuberculous mycobacteria strains, suggesting that enzyme profiles can also be used for strain characterization within the same species. J Nat Prod, 1997 May, 60(5), 431 - 8 Isolation and characterization of new anti-HIV and cytotoxic leads from plants, marine, and microbial organisms; McKee TC et al.; New cytotoxic isomalabaricane triterpenes have been isolated from a sponge Stelletta sp . (1-7); anti-HIV pterocarpans (8 and 9) and isoflavanoids (12-16 and 18) were elucidated from two tropical plants in the genus Erythrina; and anti-HIV enniatins (20 and 22-23) were characterized from fungi in the genera Fusarium and Alternaria . The enniatins were evaluated for in vivo anti-HIV activity in the hollow fiber assay. Obstet Gynecol, 1997 May, 89(5 Pt 2), 836 - 8 Postpartum endometritis caused by herpes simplex virus; Hollier LM et al.; BACKGROUND: Herpes simplex virus (HSV) is rarely the causative agent of endometritis and is usually found in association with pelvic inflammatory disease . Only one case of postpartum HSV endometritis has been reported . CASES: We describe two cases of herpes simplex postpartum endometritis . Neither patient had genital HSV lesions noted at the time of delivery . The first case developed after a preterm cesarean delivery in an 18-year-old primipara . She had persistent puerperal fever despite broad-spectrum anti-microbial treatment . The second case was a 16-year-old primipara whose vaginal delivery was complicated by severe postpartum endometritis . Vulvar and endometrial cultures were positive for HSV alone in both patients . Both infants died from disseminated HSV infection . CONCLUSION: Herpes simplex virus can cause clinical postpartum endometritis. J Nutr, 1997 May, 127(5 Suppl), 951S - 957S The public health threat of emerging viral disease; Morse SS; "Emerging diseases" are those that either have newly appeared in the population or are rapidly increasing their incidence or expanding their geographic range . Emerging viruses usually have identifiable sources, often existing viruses of animals or humans that have been given opportunities to infect new host populations ("viral traffic") . Environmental and social changes, frequently the result of human activities, can accelerate viral traffic, with consequent increases in disease emergence . Host factors, including nutrition, have often received less attention in the past but are of considerable importance . These factors, combined with the ongoing evolution of viral and microbial variants, make it likely that emerging infections will continue to appear and probably increase, emphasizing the need for effective surveillance. J Nutr, 1997 May, 127(5 Suppl), 814S - 818S Plant limitations to fiber digestion and utilization; Buxton DR et al.; Energy availability from forages is limited by fiber concentration because fiber is slowly and incompletely digested, whereas cell solubles are almost completely digested . Thus, the proportion of fiber to cell solubles is a major determinant of energy availability in forages . Grasses normally have more fiber than legumes, especially in leaves . Grass fiber is more digestible than that of legumes, but that of legumes digests at a faster rate . Ruminants digest 40-50% of legume fiber and 60-70% of grass fiber . Some fiber cannot be digested no matter how long it remains in the rumen . Lignin is thought to interfere with microbial degradation of fiber polysaccharides by acting as a physical barrier and by being cross-linked to polysaccharides by ferulate bridges . In addition to the effects of lignin, physical and structural barriers may limit fiber digestibility . Because the middle lamella and primary wall of thick-walled cells are so highly lignified, many cells can be digested only from the interior of the cell . For many cells, access to cell interiors is limited because of large particle sizes . Forage digestibility could be improved by reducing the amount of lignified cells or by developing improved cultivars so that lignified cells are more digestible. Carcinogenesis, 1997 May, 18(5), 919 - 24 Mammalian DNA repair methyltransferases shield O4MeT from nucleotide excision repair; Samson L et al.; O6-Methylguanine (O6MeG) and O4-methylthymine (O4MeT) are potentially mutagenic DNA lesions that cause G:C-->A:T and A:T-->G:C transition mutations by mispairing during DNA replication, and the repair of O6MeG and O4MeT by DNA repair methyltransferases (MTases) is therefore expected to prevent methylation-induced transitions . The efficiency of O6MeG and O4MeT repair by different MTases can vary by several hundred-fold and the aim of this study was to establish the biological consequences of such differences in the efficiency of repair . The ability of three microbial and two mammalian MTases to prevent methylation-induced G:C-->A:T and A:T-->G:C transitions is taken as a measure of their ability to repair O6MeG and O4MeT in vivo respectively . All five MTases give complete protection against G:C-->A:T transitions . However, while the microbial MTases give complete protection against A:T-->G:C transitions, the mammalian MTases actually sensitize cells to A:T-->G:C transitions . We hypothesize that the mammalian MTases bind O4MeT lesions in vivo but that, because they are extremely slow at subsequent methyl transfer, binding shields O4MeT from repair by the nucleotide excision repair pathway . Results are presented to support this hypothesis. Biochem Mol Biol Int, 1997 May, 41(6), 1137 - 41 Encystment-specific mRNA is accumulated in the resting cysts of the ciliate Colpoda inflata; Benitez L et al.; From a random amplified polymorphism cDNA study using vegetative, precystic and mature resting cysts of the ciliate Colpoda inflata, a stage-specific fragment was isolated from the resting cyst cDNA population . This fragment was used as an encystment probe to study the corresponding mRNA expression during this eukaryotic cell differentiation process . This transcript is accumulated in the resting cyst of this ciliate, and it is the first time that accumulation of specific mRNA molecules associated with the ciliate cryptobiosis process is reported . The meaning of this stored mRNA in microbial cryptobiotic stages is discussed. Mol Ecol, 1997 May, 6(5), 475 - 82 Effect of PCR template concentration on the composition and distribution of total community 16S rDNA clone libraries; Chandler DP et al.; Total DNA from sediment samples was isolated by a direct lysis technique . Purified DNA was used as template either undiluted or diluted 1:10 prior to polymerase chain reaction (PCR) amplification of 16S rRNA genes . Full-length inserts were analysed for restriction fragment length polymorphisms (RFLP) with the enzyme Cfo1, and the resulting distribution and abundance of RFLP patterns compared between the undiluted and diluted PCR reactions . Results indicate that for low PCR template concentrations, in the range from a few picograms to tens of picograms DNA, proportional representation of specific RFLP types was not reproducible upon template dilution, confirming that PCR amplification of 16S rDNA cannot be used directly to infer microbial abundance . In particular, only 15-24% of the RFLP types recovered from a sample were present in both the undiluted and diluted extracts . We propose that very low template concentrations in the PCR generate random fluctuations in priming efficiency, which led to the contrast in RFLP types observed in the libraries from the undiluted and diluted extracts. J Anim Sci, 1997 May, 75(5), 1415 - 24 Urea in dry-rolled corn diets: finishing steer performance, nutrient digestion, and microbial protein production; Milton CT et al.; In Exp . 1, 88 yearling steers (332 kg) were fed dry-rolled corn finishing diets to evaluate effects of dietary urea level on performance and carcass characteristics . Diets contained 0, .5, 1.0, or 1.5% urea (DM basis), which supplied all supplemental N, and 10% chopped prairie hay . Gains (P = .10) and gain efficiency (G/F; P < .05) were increased by .5% urea, with little improvement by additional urea . Regression analysis estimated optimal dietary urea at .9% of DM for ADG and G/F . Fat thickness (P < .05) and yield grade (P < .10) increased linearly with dietary urea level . In Exp . 2, four ruminally and duodenally cannulated steers (557 kg) were fed the diets used in Exp . 1 to evaluate effects of dietary urea on site and extent of digestion . True ruminal OM and starch digestion were increased 25 and 37%, respectively, by .5% urea, but higher urea levels did not differ from .5% . Flows of total N and microbial N to the duodenum were not affected by urea level . In Exp . 3, 100 yearling steers (347 kg) were fed dry-rolled corn finishing diets that contained 10% alfalfa hay as the dietary roughage to evaluate effects of dietary urea level on performance and carcass characteristics . Urea levels were 0, .35, .70, 1.05, or 1.40% urea (DM basis), with no other supplemental N provided . Dry matter intake (P = .10), ADG (P < .05), and G/F (P < .05) increased with intermediate concentrations of urea but decreased with the highest concentration . Regression analysis indicated that the optimal dietary urea level was .5% of DM for ADG and G/F . Urea increased dietary energy utilization but not metabolizable protein supply. J Anim Sci, 1997 May, 75(5), 1299 - 307 Efficacy of Natuphos in sorghum-based diets of finishing swine; O'Quinn PR et al.; The efficacy of a recombinantly derived microbial phytase (Natuphos 5000, BASF Corp.) was evaluated in sorghum-soybean meal-based diets of finishing swine . During the 50- to 80- and 80- to 118-kg BW intervals, diets contained .40 and .39% plant P, respectively; control diets fed during the two weight intervals were supplemented with .08 and .04% inorganic P from dicalcium phosphate . The all plant-P diets were supplemented with 0, 300, or 500 phytase units (FTU) per kilogram of diet . Supplemental P (P = .09) and phytase (linear, P = .01) increased growth rate but did not affect feed efficiency . Dietary treatment did not affect quantitative carcass traits, CP, fat, or moisture content of the loin or taste panel scores of the cooked loin other than a quadratic decrease (P = .02) in connective tissue amount as phytase supplementation increased . Apparent ileal and total tract digestibilities of DM, GE, and N were not affected (P > .25) by phytase supplementation, whereas ileal and total tract digestibilities of Ca and P increased (P < .05 or P < .01) with increasing phytase supplementation . Ultimate load and ash content of the third and fourth metacarpals and metatarsals and serum P levels increased in response to inorganic P and phytase supplementation . Pig performance, carcass traits, and bone traits were essentially equal for the 300 and 500 FTU/kg treatments . These results show that phytase effectively liberates P in sorghum-based diets, and that 300 FTU/kg (or less) will optimize performance and carcass merit of finishing swine. J Am Dent Assoc . 1997 May;128(5):648. Antibiotic use in dentistry . ADA Council on Scientific Affairs; The usefulness of diagnostic tests on pericardial fluid; Department of Internal Medicine, Kansas University Medical Center, Kansas City, USASTUDY OBJECTIVES: To determine the physical, chemical, and cellular characteristics of pericardial fluid in various disease states and to assess their diagnostic accuracies . SETTING: A metropolitan university hospital . DESIGN: Consecutive case series . PATIENTS: One hundred seventy-five hospital patients, aged 1 month to 87 years, who had undergone pericardiocentesis (n = 165) or control subjects who had undergone open heart surgery (n = 10) between 1984 and 1996 . MEASUREMENTS: The appearance of pericardial fluid and results of chemistry tests, cell counts, cytologic studies, Gram's stain, and microbial cultures were obtained by chart review . The etiology of each pericardial fluid sample was determined using prospective diagnostic criteria . RESULTS: Exudates differed from transudates by higher leukocyte counts and ratios of fluid to serum lactate dehydrogenase levels . Fluid glucose levels were significantly less in exudates . Sensitivity for detecting exudates was high for specific gravity > 1.015 (90%), fluid total protein > 3.0 g/dL (97%), fluid to serum protein ratio > 0.5 (96%), fluid lactate dehydrogenase ratio > 0.6 (94%), and fluid to serum glucose ratio < 1.0 (85%) . None of these indicators were specific . Fluid total protein and specific gravity were moderately correlated (r = 0.56) . Fluid cytologic study had a sensitivity of 92% and specificity of 100% for malignant effusion . No other test was diagnostic for a specific etiology . Among infection-associated effusions, culture-positive fluid had more neutrophils, higher lactate dehydrogenase levels, and lower ratios of fluid to serum glucose than culture-negative (parainfective) fluid . CONCLUSIONS: Evaluation of pericardial fluid might be limited to cell count, glucose, protein, and lactate dehydrogenase determinations plus bacterial culture and cytology . While not used routinely, other tests that may be highly specific for particular diseases should be ordered only to confirm a high clinical suspicion. Urology, 1997 May, 49(5A Suppl), 14 - 40 Interstitial cystitis: a critique of current concepts with a new proposal for pathologic diagnosis and pathogenesis; Elbadawi A; Interstitial cystitis (IC) has continued to be an unresolved problem in clinical urology despite intense investigation over the past 16 or more years . Its etiology and pathogenesis are still undetermined, and its pathologic diagnosis is essentially one of exclusion, with no specific or clear criteria . In this review, current concepts of the etiology/pathogenesis and pathology are critically analyzed, new pathologic observations summarized, and a proposal of neurogenic inflammation as the primary pathogenetic factor is presented in the context of all currently available information . The popular postulate attributing IC to a deficient or defective glycosaminoglycan urothelial surface layer is not substantiated by morphologic, experimental, clinical, or therapeutic observations . Although the consensus seems to discount an infectious etiology, there is sufficient evidence that a microbial factor-short of a bona fide clinical infection-may have a role . Both autoimmunity and mast cell infiltration also appear to have a role, despite the lack of evidence that either is involved as the primary etiologic factor . Claims that the so-called feline urologic syndrome may represent a natural animal model of IC are shaky . As it now stands, there is no natural or induced animal model that duplicates IC as it occurs in humans . No specific or diagnostic light microscopic pathologic features are provided by either routine histopathology or immunohistochemistry . Increasingly, it has been recognized that detrusor mast cell count has little or no diagnostic value . On the other hand, electron microscopy has provided important new observations: (a) presence of mast cells, activated by piecemeal degranulation, in close proximity to intrinsic nerves-particularly in suburothelium: (b) distinctive pathologic changes in urothelium, suburothelium, and muscularis in biopsy samples obtained after diagnostic bladder hydrodistension; (c) constant associated changes in venules, capillaries, and neural elements in the same biopsy samples; and (d) diffuse involvement of bladder wall, with the most evident and profound pathologic changes in posthydrodistension biopsy samples obtained from cystoscopically obvious lesions (glomerulations) . These features are sufficiently distinctive to allow definitive pathologic diagnosis of IC, and provide a firm basis for primary involvement of neurogenic inflammation in its pathogenesis . A proposal is presented regarding the mechanisms invoked by neurogenic inflammation . This proposal revolves around sensory nerve excitation, the release of neuropeptides, and activated differential secretion of potent mast cell mediators . This proposal can account for the heterogeneity and variability of observed pathologic features, and upholds the tacit acceptance of IC as a disease of pluricausal etiology and multifactorial pathogenesis. Appl Environ Microbiol, 1997 May, 63(5), 1861 - 5 Preparation of GM1 ganglioside with sialidase-producing marine bacteria as a microbial biocatalyst; Fukano Y et al.; This paper describes the preparation of monosialoganglioside GM1 with sialidase-producing marine bacteria as a microbial biocatalyst . A new sialidase-producing bacterium, identified tentatively as Pseudomonas sp . strain YF-2, was isolated from seawater by enrichment culture with ganglioside as the sole source of carbon . When YF-2 was cultured in a synthetic medium containing crude bovine brain gangliosides at 25 degrees C for 3 days, 80 to 90% of the gangliosides were converted to GM1 . GM1 was then purified from the supernatant of YF-2 culture by C18 reverse-phased chromatography, followed by DEAE-Sephadex A25 anion-exchange chromatography . In a typical experiment, 178 mg of highly purified GM1 was obtained from 500 mg of the crude ganglioside fraction . The GM1 induced neurite outgrowth of neuroblastoma Neuro2a cells at a concentration of 33 to 100 microM in the presence of fetal calf serum . Sialidase was purified 33-fold with 13.3% recovery from the culture supernatant of YF-2 . The purified enzyme hydrolyzed polysialogangliosides to produce GM1 but did not act on GM1 . It was therefore concluded that polysialogangliosides in the culture of strain YF-2 were converted to GM1 by this sialidase. Clin Infect Dis, 1997 May, 24(5), 945 - 50 Prospective analysis of genital ulcer disease in Brooklyn, New York; Dillon SM et al.; We prospectively studied 82 men and women with first episodes of genital ulceration . By using newer diagnostic techniques, a definite microbial etiology of 84 infections in 65 of the 82 patients evaluated was found . There were 33 cases of definite primary syphilis, 27 of definite chancroid, and 24 of definite genital herpes simplex . Conclusive evidence of more than one microbial etiology was found for 19 (23%) of the patients . Simultaneous primary syphilis and chancroid was the third most common ulcer infection . This finding underscores the need for both clinical suspicion of multiple infections in patients with genital ulcers and comprehensive testing for all suspicious etiologies. Hepatology, 1997 May, 25(5), 1255 - 7 Association of seropositivity for hepatitis viruses and aplastic anemia in Thailand; Issaragrisil S et al.; Aplastic anemia is more common in the Orient than in western countries, with an incidence in Thailand that is 2- to 3-fold higher than in Europe . Aplastic anemia after hepatitis is a well characterized clinical entity, and clinical hepatitis is also prevalent in the Far East . We performed a prospective case-control study to determine risk factors for aplastic anemia in Bangkok and two rural regions during 1989 to 1994 . A total of 375 cases were identified, along with 1,174 hospital controls matched for age and sex . Historical data were collected by trained interviewers . Sera from a subset of cases (N = 177) and controls (N = 183) were tested for antibodies to hepatitis viruses A, B, and C and hepatitis B surface antigen . There was no evidence of association of aplastic anemia with hepatitis B or hepatitis C . Previous exposure to hepatitis A, as determined by immunoglobulin G (IgG) seropositivity, was significantly associated with aplastic anemia: the relative risk adjusted for confounding was 2.9 (95% confidence interval 1.2-6.7) . The same association also existed for persons under age 25 years, in whom the prevalence of hepatitis A IgG was lower than in the total population . However, no patients showed evidence of recent infection with hepatitis A (immunoglobulin M {IgM} seropositivity) . These results indicate that exposure to a hepatitis virus is a risk indicator for aplastic anemia in Thailand, and while itself unlikely to be etiologic, hepatitis A may be a surrogate marker for another enteric microbial agent. Cancer Res, 1997 May 1, 57(9), 1710 - 6 Irreversible and reversible topoisomerase II DNA cleavage stimulated by clerocidin: sequence specificity and structural drug determinants; Binaschi M et al.; In contrast to other topoisomerase II poisons, the microbial terpenoid clerocidin was shown to stimulate irreversible topoisomerase II-mediated DNA cleavage . To establish the structural determinants for drug activity, in this study we have investigated intensity patterns and sequence specificity of clerocidin-stimulated DNA cleavage using 5'-end 32P-labeled DNA fragments . At a majority of the sites, clerocidin-stimulated cleavage did not revert upon NaCl addition; nevertheless, at some sites, cleavage completely reverted . Statistical analyses showed that drug-preferred bases were different in the two cases: guanine and cytosine were highly preferred at position -1 at irreversible and reversible sites, respectively . These results demonstrated that cleavage irreversibility was site selective and required a guanine at the 3' end of the cut . Further experiments revealed that some irreversible sites showed an abnormal electrophoretic mobility in sequencing gels with respect to cleaved bands generated by 4-(9-acridinylamino)methanesulfon-m-anisidide, suggesting a chemical alteration of the DNA strand . Interestingly, the ability to stimulate irreversible cleavage progressively decreased over time when clerocidin was stored in ethanol . Under these conditions, nuclear magnetic resonance measurements demonstrated that the drug underwent structural modifications that involved the C-12-C-15 side chain . Thus, the results indicate that a specific moiety of clerocidin may react with the DNA (guanine at -1) in the ternary complex, resulting in cleavage irreversibility and in altered DNA mobility in sequencing gels. Mol Cells, 1997 Apr 30, 7(2), 192 - 9 Identification of putative phosphoinositide-specific phospholipase C genes in filamentous fungi; Jung OJ et al.; Five putative phosphoinositide-specific phospholipases C (PLC) genes were identified in three species of filamentous fungi . Using polymerase chain reaction with degenerate oligonucleotide primers, gene fragments encoding amino acid sequences homologous to PLCs of mammals and other organisms were amplified: one sequence from Botryotinia fuckeliana, one from Aspergillus nidulans, and three from Neurospora crassa . The molecular cloning and sequencing of a putative PLC gene (BCPLC1) from B . fuckeliana showed that it encoded a polypeptide containing X and Y domains, the two conserved regions found in all known PLCs . The hypothetical gene product of BCPLC1 was of delta type in its primary structural organization . The identification of three PLC genes in N . crassa shows that multiple PLC isozymes also occur in microbial eukaryotes. J Biol Chem, 1997 Apr 18, 272(16), 10389 - 95 Identification and characterization of a novel Ets-2-related nuclear complex implicated in the activation of the human interleukin-12 p40 gene promoter; Ma X et al.; Interleukin-12 (IL-12) is a proinflammatory cytokine produced by antigen-presenting cells in response to many microbial infections . IL-12 plays an important role in the generation of T helper type-1 cells, which favor cell-mediated immune response . IL-12 is composed of two different subunits, p40 and p35, whose expression can be regulated concomitantly or differentially . Monocytic cells, the major producers of IL-12, can be primed by interferon-gamma (IFN-gamma) to produce optimal amounts of IL-12 in response to LPS stimulation as a consequence of bacterial infection . The priming effect is exerted primarily at the transcriptional level on the p40 promoter in conjunction with the effects of LPS, possibly by inducing specific transcription factors, which individually have no direct effect but which cooperatively can activate the promoter . We examined in detail one of these DNA-protein interactions observed around an Ets-2 element situated at -211/-207 of the p40 promoter, which is known to be a functionally critical site . This region interacts with a nuclear complex termed F1 that appears to be highly inducible by either IFN-gamma treatment for 16 h or lipopolysaccharide stimulation for 8 h . F1 binding to the Ets-2 site requires a considerable amount of spacing around the Ets-2 site, as revealed by gel mobility shift and in vitro methylation assays . Supershift experiments and DNA affinity purification indicated that both Ets-2 and a novel, antigenically related protein with an approximate molecular mass of 109 kDa are part of the F1 complex, together with additional components including IRF-1 and c-Rel . This novel protein is designated GLp109 for its inducibility by IFN-gamma or lipopolysaccharide . Its possible role in the activation of the IL-12 p40 promoter is discussed. J Theor Biol, 1997 Apr 7, 185(3), 367 - 72 A mathematical model to determine the optimal number of fragments for comparison of bacterial chromosomic macrorestriction patterns; Mendez-Alvarez S et al.; To our knowledge, although comparison of chromosomic macrorestriction patterns has become one of the most feasible molecular tools of the current microbial taxonomy, a mathematical approach to optimize the choice of a restriction enzyme among the endonucleases tested for such comparison has not been previously described . The coincidence of restriction patterns for two tested bacterial strains with this chosen endonuclease will ensure a high genetic relatedness between them . We report a mathematical model to determine the probability of hazardously obtaining a particular chromosomic macrorestriction pattern by PFGE and to calculate the optimal number of fragments for its comparison . The model presented allows us to determine the optimal number of fragments in order to compare chromosomic restriction patterns . The model calculates this values as a function of the chromosome size and the restriction site length . The model is not useful for choosing a restriction enzyme previous to experimental steps, but as a tool for the choice of the restriction enzyme that yields the lowest probability of hazardously obtaining coincidences of chromosomic patterns . The applicability of this model has been exemplified by determining the optimal number of fragments for some well-characterized bacteria and by comparing these values with those that have been experimentally used. Nervenarzt, 1997 Apr, 68(4), 292 - 7 {Infection: impaired consciousness as the initial symptom . Clinical and pathophysiologic aspects of septic encephalopathy}; Schwarz S et al.; Septic encephalopathy (SE) is present in up to 70% of all patients with sepsis . In some cases, SE may proceed other parameters of sepsis . Loss of consciousness to a various extent is the leading symptom . CSF findings and CCT are usually unremarkable . EEG is a sensitive parameter to monitor SE . EEG-changes deteriorate in correspondence to the degree of SE . If sepsis can be treated successfully, clinical and electrophysiological signs are completely reversible . SE has a complex etiology . Bacterial endotoxins and other microbial products trigger the release of a multitude of mediators of sepsis . Due to liver dysfunction in sepsis, the brain neurotransmitter profile may be deranged . Other etiological factors include bacteriemia, liver or renal dysfunction, fluid and electrolyte imbalance, hypoglycemia and drug effects . Due to the prognostic significance of early adequate treatment, recognition of SE as a possible initial sign may be crucial for patients with sepsis. Biol Trace Elem Res, 1997 Apr, 57(1), 1 - 8 A longitudinal study of unsaturated iron-binding capacity and lactoferrin in unstimulated parotid saliva; Mukherjee S et al.; Availability of iron is one important nutritional parameter for microbial growth in saliva . This longitudinal study measured the diurnal and day-to-day variations in the total iron (TI), total iron-binding capacity (TIBC), unsaturated iron-binding capacity (UIBC), and lactoferrin (LF) in unstimulated human parotid saliva . Saliva was collected from 15 young male subjects in the morning and afternoon hours each day for five consecutive days . The TI and TIBC were determined by flameless atomic absorption spectroscopy, and UIBC was determined by subtraction of TI from TIBC . The LF was determined by "sandwich" enzyme-linked immunosorbent assay (ELISA) . One peripheral blood sample of each subject was also analyzed for TI, TIBC, and ferritin . The results showed no significant diurnal or day-to-day variation of TI, TIBC, UIBC, or LF in saliva for most subjects . However, significant between-subject variations were observed for most parameters . Variations ranged from subjects with constantly positive UIBC values to subjects with constantly negative UIBC values . The relationship between the LF values and the TI and TIBC values suggests that other iron-binding protein(s) are present in saliva . Also, saliva had significantly lower TIBC values than serum . This finding indicated that iron may be easily available in saliva . However, further studies are required to determine the relationship between UIBC value of saliva and oral and dental diseases, and also to detect the presence of other iron-binding proteins in saliva. Chem Biol, 1997 Apr, 4(4), 279 - 86 Stevastelins, a novel group of immunosuppressants, inhibit dual-specificity protein phosphatases; Hamaguchi T et al.; BACKGROUND: Since the molecular target of the immunosuppressive reagents FK506 and cyclosporin A was revealed to be protein phosphatase PP2B (calcineurin), many researchers have been screening the protein phosphatase inhibitors from microbial metabolites to develop new immunosuppressive reagents . We isolated stevastelin B, which is composed of valine, threonine, serine and 3,5-dihydroxy-2,4-dimethyl stearic acid, and stevastelin A, which is a sulphonylated derivative of stevastelin B . To understand the action mechanism of stevastelins A and B, we synthesized a series of stevastelin derivatives and investigated their structure-activity relationships . RESULTS: A series of stevastelin derivatives have been systematically synthesized . Stevastelin B inhibited gene expression that is dependent on interleukin-2 (IL-2) or IL-6 promoters in situ, but it had no inhibitory activity against any protein phosphatases in vitro . In contrast, stevastelin A, which is a sulphonylated derivative of stevastelin B, inhibited the phosphatase activity of a dual-specificity phosphatase, VH1-related human protein (VHR), in vitro, but it had no inhibitory activity against gene expression or cell-cycle progression in situ . CONCLUSIONS: Stevastelin B is a novel immunosuppressant . It inhibited IL-2 or IL-6 dependent gene expression but did not inhibit the phosphatase activity of calcineurin . The structure-activity relationships show that the acidic functional group on the threonine residue and the stearic acid moiety in the stevastelin molecule are important for inhibitory effects on the dephosphorylation activity of VHR in vitro . Stevastelin B might be sulphonylated or phosphorylated after incorporation into the target cell, and then it interacts with protein tyrosine phosphatases and regulates cell-cycle progression. Aliment Pharmacol Ther, 1997 Apr, 11(2), 317 - 22 Randomized study comparing omeprazole plus amoxycillin versus omeprazole plus clarithromycin for eradication of Helicobacter pylori; Spinzi G et al.; BACKGROUND: Dual therapy with omeprazole plus amoxycillin or with omeprazole plus clarithromycin has been proposed for eradication of Helicobacter pylori . The main problem is the great variability in the rate of eradication . METHODS: A group of 287 consecutive patients with active peptic ulcers and H . pylori infections were admitted to a prospective, randomized, multicentre study, to be given omeprazole 20 mg b.d . plus either amoxycillin 1 g b.d . or clarithromycin 500 mg t.d.s . for 2 weeks . Cure was defined as the absence of H . pylori infection, 4-6 weeks after completing anti-microbial therapy, assessed by urease activity and histology of antral and body gastric biopsies . RESULTS: The bacteria were eradicated in 68/143 patients (48%) treated with amoxycillin and omeprazole and 70/144 patients (49%) treated with clarithromycin and omeprazole (intention-to-treat analysis) . The ulcers were healed in 118/127 patients (93%) treated with amoxycillin and in 115/123 (94%) of those treated with clarithromycin . Undesirable effects were rare with both treatments . CONCLUSIONS: Combined treatment with omeprazole plus either amoxycillin or clarithromycin produced a high percentage of short-term healing of ulcers and was well tolerated, but is not useful as first-line anti-Helicobacter pylori treatment. Biosci Biotechnol Biochem, 1997 Apr, 61(4), 609 - 14 Microbial extracellular glycolipid induction of differentiation and inhibition of the protein kinase C activity of human promyelocytic leukemia cell line HL60; Isoda H et al.; The biological activities of 7 microbial extracellular glycolipids including mannosylerythritol lipid (MEL)-A, MEL-B, polyol lipid (PL), rhamnolipid (RL), sophorose lipid (SL), succinoyl trehalose lipid (STL)-1, and STL-3 were investigated . All glycolipids except for RL were found to induce cell differentiation instead of cell proliferation in the human promyelocytic leukemia cell line HL60 . To identify the differentiation direction of the induced cells, the leukocyte esterase activities were cytologically investigated, and the results showed that MEL-A, MEL-B, and PL induced HL60 to differentiate into granulocytes, while SL, STL-1, and STL-3 induced differentiation into monocytes . The 6 effective glycolipids also increased nitroblue tetrazolium (NBT) reducing ability, which is a common differentiation-associated characteristic in monocytes and granulocytes . Furthermore, it was also observed that these 6 glycolipids inhibited the activity of phospholipid- and Ca(2+)-dependent protein kinase . Additionally, the 6 effective glycolipids also induced the human myelogenous leukemia cell line K562 and the human basophilic leukemia cell line KU812 to differentiate into monocytes, granulocytes, and megakaryocytes. Biosci Biotechnol Biochem, 1997 Apr, 61(4), 592 - 8 Purification, characterization, and cDNA cloning of a novel alpha-galactosidase from Mortierella vinacea; Shibuya H et al.; A novel alpha-galactosidase, designated alpha-galactosidase II, was isolated from the culture filtrate of Mortierella vinacea . The molecular size of the purified enzyme estimated by gel filtration was 60 kDa, which agreed with that, 51-62 kDa, estimated by SDS-PAGE . The enzyme was thermolabile at neutral pH, but the addition of BSA to the enzyme solution at the concentration of 0.01% increased its stability considerably . The enzyme appears to be novel because it showed a distinct substrate specificity from other microbial alpha-galactosidases on galactomanno-oligosaccharides, prepared from galactomannan, that is, the enzyme liberated not only side-chain alpha-galactosyl residue from 6(3)-mono-alpha-D-galactopyranosyl-beta-1,4-D-mannotetraose but also terminal alpha-galactosyl residue from 6(3)-mono-alpha-D-galactopyranosyl-beta-1,4-D-mannotriose . In addition, the enzyme acted on galactomannans effectively . alpha-Galactosidase II cDNA was cloned and its nucleotides sequenced . The deduced amino acid sequence showed that the mature enzyme consisted of 376 amino acid residues with a molecular mass of 41,334 Da . The derived amino acid sequence of the enzyme showed 31-49% sequence similarity with those of alpha-galactosidases from other origins. Microbiology, 1997 Apr, 143 ( Pt 4), 1451 - 9 Methylosphaera hansonii gen . nov., sp . nov., a psychrophilic, group I methanotroph from Antarctic marine-salinity, meromictic lakes; Bowman JP et al.; Methanotrophic bacteria were enumerated and isolated from the chemocline and surface sediments of marine-salinity Antarctic meromictic lakes located in the Vestfold Hills, Antarctica (68 degrees S 78 degrees E) . Most probable number (MPN) analysis indicated that at the chemocline of Ace Lake the methanotroph population made up only a small proportion of the total microbial population and was sharply stratified, with higher populations detected in the surface sediments collected at the edge of Ace Lake and Burton Lake . Methanotrophs were not detected in Pendant Lake . Only a single phenotypic group of methanotrophs was successfully enriched, enumerated and isolated into pure culture from the lake samples . Strains of this group were non-motile, coccoidal in morphology, did not form resting cells, reproduced by constriction, and required seawater for growth . The strains were also psychrophilic, with optimal growth occurring at 10-13 degrees C and maximum growth temperatures of 16-21 degrees C . The ribulose monophosphate pathway but not the serine pathway for incorporation of C1 compounds was detectable in the strains . The guanine plus cytosine (G + C) content of the genomic DNA was 43-46 mol% . Whole-cell fatty acid analysis indicated that 16:1 omega 8c (37-41%), 16:1 omega 6c (17-19%), 16:1 omega 7c (15-19%) and 16:0 (14-15%) were the major fatty acids in the strains . 16s rDNA sequence analysis revealed that the strains form a distinct line of descent in the family Methylococcaceae (group I methanotrophs), with the closest relative being the Louisiana Slope methanotrophic mytilid endosymbiont (91.8-92.3% sequence similarity) . On the basis of polyphasic taxonomic characteristics the Antarctic lake isolates represent a novel group I methanotrophic genus with the proposed name Methylosphaera hansonii (type strain ACAM 549). J Periodontal Res, 1997 Apr, 32(3), 326 - 34 Bacterial metabolites sodium butyrate and propionate inhibit epithelial cell growth in vitro; Pollanen MT et al.; The structural and functional barrier preventing the free advancement of microbial plaque subgingivally along the tooth surface is formed by the junctional epithelial (JE) cells directly attached to the tooth (DAT cells) . The mechanism leading to degeneration of the DAT cells is not known . In the present study we examined the possible role of short chain fatty acids (SCFAs) on epithelial cells by making use of 2 epithelial cell cultures (HaCaT and ERM) and an explant culture model of human JE . The SCFAs butyrate and propionate were used in concentrations found in human plaque and gingival crevicular fluid (0.25-16.0 mM) . The SCFAs had no effect on primary cell adhesion nor on the epithelial attachment apparatus (EAA) . By contrast, even 0.25 mM of butyrate significantly retarded epithelial cell growth . Similar effects with propionate were first observed at concentrations higher than 1.0 mM . The retardation of epithelial cell growth was found to be due to inhibition of cell division . Furthermore, after butyrate treatment dense accumulations of intermediate filaments and cytoplasmic vacuolization were characteristically seen in cells adjacent to cells of normal appearance . This suggests that some cells of the growing epithelial cell population are more sensitive to the SCFAs than others, and agrees with previous reports on the DAT cells of periodontally-involved teeth in vivo . The results suggest that SCFAs are microbial factors that play a role in the initiation and progression of periodontal pocket formation by impairing epithelial cell function rather than having a direct effect on the EAA. Biomaterials, 1997 Apr, 18(8), 635 - 41 Physico-chemical properties of a rifampicin-releasing polydimethylsiloxane shunt; Schierholz JM; Infection of implanted polymeric devices is a major problem in modern medicine . Silicone shunts were modified in order to prevent microbial colonization by incorporating rifampicin . The release mechanism and the altered properties of the silicone were studied . Release rates of rifampicin out of the polymeric shunt materia were measured in vitro for up to 60 d . For high velocity of rifampicin in the polymeric matrix and long-lasting controlled release rates, high compatibility of polymer and drug was required . Compatibility and therefore miscibility of drug and polymer were estimated by reduced solubility and cohesion energy densities (Hansen parameter, solubility parameter delta) . Mechanical properties of the polymer were influenced by incorporation of small drug amounts, characterized by stress-strain curves . Differential scanning calorimetry (DSC) measurements suggested thermodynamically controlled interaction of the macromolecules with the incorporated substance . The physico-chemical state of the drug in the internal phase and the surface of the polymer was studied by scanning electron micrography (SEM), showing homogeneous molecular dispersion of the drug in the polymeric material as well as crystalline structures on the surface. J Hepatol, 1997 Apr, 26(4), 839 - 44 Early microbiologic diagnosis of spontaneous bacterial peritonitis with BacT/ALERT; Ortiz J et al.; BACKGROUND/AIMS: Inoculation of ascitic fluid into conventional blood culture bottles is more sensitive than conventional culture in the diagnosis of spontaneous bacterial peritonitis . BacT/ALERT is an automated colorimetric microbial detection system that has been shown to be faster than conventional blood culture bottles in the diagnosis of bacteremia . The aim of the study was to compare the BacT/ALERT system with the conventional culture and the conventional blood culture bottles method in the diagnosis of spontaneous bacterial peritonitis . METHODS: All the ascitic fluid samples from patients with cirrhosis hospitalized in our Department between September 1992 and May 1994 (n=1032) were prospectively evaluated . In all cases, an aliquot of ascitic fluid was sent for Gram's stain and conventional culture, and 20 ml were inoculated at the bedside into blood culture bottles: 10 ml into conventional blood culture bottles and 10 ml into BacT/ALERT . RESULTS: Thirty ascitic fluid infections (23 spontaneous bacterial peritonitis and 7 neutrocytic ascites) and 20 bacterascites were diagnosed . Conventional culture was positive in 10/30 ascitic fluid infections (33.3%), conventional blood culture bottles in 22/30 (73.3%) (p<0.01 compared to conventional culture) and BacT/ALERT in 20/30 (66.6%) (p<0.05 compared to conventional culture, pNS compared to conventional blood culture bottles) . The time elapsed for culture positivity was 43.4+/-34.2 h for conventional blood culture bottles and 13.3+/-9.2 h for BacT/ALERT (p<0.001) . Thirteen of the 23 cases of spontaneous bacterial peritonitis (56.5%) were detected within the first 12 h with BacT/ALERT, as compared to only three (13%) with conventional blood culture bottles (p<0.03) . CONCLUSION: The automated system BacT/ALERT provides an earlier microbiologic diagnosis of spontaneous bacterial peritonitis than conventional blood culture bottles with similar sensitivity. J Immunol, 1997 Apr 1, 158(7), 3511 - 20 Vaccine-specific antibody responses induced by HIV-1 envelope subunit vaccines; Pincus SH et al.; The first generation of candidate vaccines to prevent HIV infection consisted of recombinant envelope proteins (Env, gp120, and gp160) derived from a single laboratory strain of HIV, designated IIIB/LAV, but produced with different expression systems . In this study we examined the fine specificity of the human Ab response to each vaccine and compared them to the responses of laboratory workers infected with the same strain of HIV . The best responders from each vaccine protocol were studied and compared . Detailed comparisons of the fine specificity of the Ab response were possible because all immunologic assays were performed using homologous recombinant proteins, peptides, and virus stocks . Although the total amounts of anti-Env Ab were comparable, the groups exhibited significant differences in epitope specificity, avidity, and functional capacity of the Ab response . The data demonstrate that the form of the immunogen (e.g., live virus or recombinant protein) is important in determining the quality of the Ab response . Conclusions are also drawn regarding characteristics of the anti-HIV-neutralizing Ab response . These studies represent one of the most detailed analyses of the human Ab response to any Ag and have implications for the development of vaccines for HIV as well as for other microbial pathogens. J Anim Sci, 1997 Apr, 75(4), 904 - 9 Influence of flake density on the comparative feeding value of a barley-corn blend for feedlot cattle; Zinn RA et al.; Ninety-six medium-frame crossbred steers (209 kg) were used in an 86-d feeding trial . Dietary treatments consisted of a 92% concentrate diet containing 76.15% (DM basis) grain as 1) steam-flaked barley (SFB), flake density (FD) = .26 kg/L; 2) blend of 2/3 barley and 1/3 corn steam-flaked (SFBLEND), FD = .36 kg/L; 3) SFBLEND, FD = .31 kg/L; 4) SFBLEND, FD = .26 kg/L . There were no treatment effects (P > .10) on growth performance of feedlot steers or NE value of the diet . Weight gain averaged 1.46 kg/d . Feed efficiency was in close agreement (101%) with expected values based on observed DMI and tabular dietary NE values . Treatment effects on characteristics of ruminal and total tract digestion were evaluated using four Holstein steers (280 kg) with cannulas in the rumen and proximal duodenum in a 4 x 4 Latin square design . Ruminal digestibility of OM (P < .01), starch (P < .01), and feed N (P < .10) increased, and ruminal N efficiency (duodenal nonammonia N/N intake, P < .01) decreased (linear component) with decreasing FD . Net microbial N flow to the small intestine was greater (P < .05) for SFB than for the SFBLEND . Total tract digestion of OM (P < .01), starch (P < .05), and DE (P < .05) was greater for the SFBLEND than for SFB . There were no treatment effects (P < .10) on postruminal and total tract digestibility of N . We conclude that blending barley and corn before flaking will have very little impact on the feeding value of the grains compared with flaking the grains separately. Pediatr Infect Dis J, 1997 Apr, 16(4), 381 - 5 Frequency of low level bacteremia in infants from birth to two months of age; Kellogg JA et al.; BACKGROUND: The frequency of low level bacteremia (< or = 10 colony-forming units/ml) in infants from birth to 2 months of age and the optimal volume of blood and number of blood cultures to be collected have not been well-documented . During 1991 guidelines at this hospital for collection of blood for culture from these infants were revised . METHODS: Blood from each infant with suspected bacteremia was usually inoculated into an Isolator 1.5 Microbial Tube (1.5 ml of blood) and a bottle of anaerobic broth (0.5 to 3.0 ml of blood) . The use of a second Isolator tube and the total blood volume recommended for culture (2 to 6 ml) depended on the weight and total blood volume of each infant . RESULTS: Forty-four bacterial pathogens were recovered from the blood of 40 (2.5%) of 1589 infants . Of 34 infants from whose blood the concentration of pathogens could be determined, 23 (68%) had low level bacteremia . Of 50 isolates of pathogens recovered from Isolator cultures, 32 (64%) were detected in counts of < or = 10 colony-forming units/ml . When 2 or 3 blood culture devices were inoculated with a total of 2 to 6 ml of blood from each infant, significantly more cases of bacteremia were detected (34 (3.0%) of 1126 infants had positive blood cultures) than when only one culture device containing < or = 1.5 ml of blood was used (2 (0.5%) of 398 infants had positive blood cultures; P = 0.008) . However, when 4 or more culture devices were inoculated with a total of > 6 ml of blood from each infant (5 (7.7%) of 65 infants had positive blood cultures), the difference in recovery of pathogens compared with the culturing of from 2 to 6 ml of blood per infant was not significant (P = 0.089) . CONCLUSIONS: Low level bacteremia was common in our infants' patient population . The culturing of up to 6 ml of blood which represented up to 4.5% of an infant's total blood volume was required for detection of the pathogens. Int J Food Microbiol, 1997 Apr 1, 35(2), 187 - 93 Electronic nose for microbial quality classification of grains; Jonsson A et al.; The odour of grains is in many countries the primary criterion of fitness for consumption . However, smelling of grain for quality grading should be avoided since inhalation of mould spores or toxins may be hazardous to the health and determinations of the off-odours are subjective . An electronic nose, i.e . a gas sensor array combined with a pattern recognition routine might serve as an alternative . We have used an electronic nose consisting of a sensor array with different types of sensors . The signal pattern from the sensors is collected by a computer and further processed by an artificial neural network (ANN) providing the pattern recognition system . Samples of oats, rye and barley with different odours and wheat with different levels of ergosterol, fungal and bacterial colony forming units (cfu) were heated in a chamber and the gas in the chamber was led over the sensory array . The ANN could predict the odour classes of good, mouldy, weakly and strongly musty oats with a high degree of accuracy . The ANN also indicated the percentage of mouldy barley or rye grains in mixtures with fresh grains . In wheat a high degree of correlation between ANN predictions and measured ergosterol as well as with fungal and bacterial cfu was observed . The electronic nose can be developed to provide a simple and fast method for quality classification of grain and is likely to find applications also in other areas of food mycology. FEMS Microbiol Lett, 1997 Apr 1, 149(1), 93 - 8 H4 histone in the macronucleus of Blepharisma japonicum (Protozoa, Ciliophora, Heterotrichida); Salvini M et al.; Two clones, obtained by polymerase chain reaction from macronuclear DNA of the unicellular ciliated protist Blepharisma japonicum, were isolated and sequenced . They correspond to fragments of two different putative H4 histone genes . The existence of multiple H4 histone genes was also suggested by Southern blot hybridisation experiments employing one of the obtained clones as a probe . Two B . japonicum H4 protein fragments, which were directly sequenced, show differences in the amino acid sequences too . The comparison of the obtained B . japonicum H4 partial amino acid sequences with each other, and with H4 from other ciliates and from representative microbial and multicellular organisms, highlights the larger histone heterogeneity of lower eukaryotes compared to that observed in higher organisms. Mol Plant Microbe Interact, 1997 Apr, 10(3), 326 - 38 A peroxidase gene promoter induced by phytopathogens and methyl jasmonate in transgenic plants; Curtis MD et al.; The expression of two closely related peroxidase isogenes, Shpx6a and Shpx6b, of the legume Stylosanthes humilis was studied using isogene-specific reverse transcriptase PCR techniques . Results indicated that transcripts of both genes were rapidly induced following inoculation with the fungal pathogen Colletotrichum gloeosporioides, wounding and treatment with the defense regulator methyl jasmonate (MeJA) . In contrast treatment of leaves of S . humilis with abscisic acid (ABA) and salicylic acid (SA) did not induce transcripts of either isogene . A genomic clone containing the Shpx6b gene was isolated and 594 bp of 5' sequence upstream of the translation start was fused in frame to the coding region of the uidA reporter gene and introduced into tobacco . Expression from the Shpx6b promoter in transgenic plants was determined by histochemical staining and quantitative assays of beta-glucuronidase (GUS) . In transgenic tobacco, GUS expression was detected in cotyledons, vascular cells of young leaves, anthers, pollen, and the stigma and style . Wounding of the tobacco plants produced very localized GUS staining . Much more extensive staining for GUS was observed following inoculation of tobacco leaves with conidia of the fungal pathogen Cercospora nicotianae and the inoculation of wound sites with mycelium of the Oomycete pathogen Phytophthora parasitica var . nicotianae . Treatment of mature leaves with methyl jasmonate induced GUS activity while treatment with ABA, SA, and H2O2 had no effect . A similar strong induction of GUS activity was measured in young transgenic seedlings germinated on MeJA while some, but much weaker, induction of GUS activity was observed in seedlings treated with SA . The sequence of the promoter contained motifs homologous to putative cis elements in other plant genes responsive to MeJA . The Shpx6b gene is the first plant peroxidase gene shown to be induced by both microbial pathogens and MeJA and its promoter will be useful for investigations of signaling processes during fungal infection and for the expression of foreign gene products at infection sites. Curr Opin Immunol, 1997 Apr, 9(2), 228 - 32 Generation of antibody diversity in rabbits; Knight KL et al.; Most rabbit B lymphocytes use the same VH gene in V(D)J gene rearrangements and undergo somatic diversification by gene conversion and hypermutation . Recent experiments have shown that V(D)J genes in essentially all rabbit B cells diversify shortly after birth and that this diversification occurs in the gut-associated lymphoid tissue . Still to be determined is whether this diversification is developmentally programmed or is driven by exogenous microbial antigens. Am J Med Sci, 1997 Apr, 313(4), 236 - 8 Behçet's-like syndrome associated with idiopathic CD4+ T-lymphocytopenia, opportunistic infections, and a large population of TCR alpha beta+ CD4- CD8- T cells; Venzor J et al.; Herein we report a patient with Behcet's like syndrome, idiopathic CD4+ T-lymphocytopenia, opportunistic infections, and a large polyclonal population of TCR alpha beta + CD4- CD8- T cells . Microfluorimetric analysis of peripheral blood mononuclear cells revealed CD4+ T-cell counts of 10 +/- 5/mm3 . The CD3+ T cells were 99% TCR alpha beta +, of which 74 +/- 5% were CD4- CD8- . No clonal populations were detected by southern analysis for T-cell receptor V beta gene rearrangements . No evidence of human immunodeficiency virus infection was present, although nocardia, candida, pneumocystis, cytomegalovirus, and herpes infections were documented . The concomitant presence of opportunistic infections and a large population of TCR alpha beta + CD4- CD8- T cells suggests a pathogenic association and an intense immune response to microbial lipid or lipoglycan antigens presented in the context of CD1 molecules . This case demonstrates the potential for idiopathic CD4+ T-lymphocytopenia to occur in Behcet's-like syndrome with lethal consequences. Appl Environ Microbiol, 1997 Apr, 63(4), 1441 - 8 A novel delta-subdivision proteobacterial lineage from the lower ocean surface layer; Wright TD et al.; A small-subunit ribosomal RNA (16S rRNA) gene lineage (SAR324) affiliated with the delta-subdivision of the class Proteobacteria (DP) was discovered in a 16S rRNA gene clone library prepared from a water sample collected from 250 m in the western Sargasso Sea . This clone library of nearly full-length amplicons of bacterial 16S rRNA genes has been the subject of previous studies aimed at identifying bacteria that inhibit the lower ocean surface layer . The novel lineage was identified by randomly sequencing clones that did not hybridize to oligonucleotide probes specific for several abundant bacterioplankton groups identified in previous studies . Phylogenetic analysis indicated that SAR324 was most closely affiliated with the DP, although it showed no specific relationship to any DP 16S rRNA genes in databases . Eight of the clones in the library of 148 clones were identified as members of the SAR324 lineage by hybridization to an oligonucleotide probe specific for SAR324 . Subsequent hybridizations showed that the SAR324 group is stratified in the lower surface layer of both the Atlantic and Pacific Oceans, with maxima between 160 and 500 m . The repeated discovery of sequences belonging to different gene clusters with similar distributions in this region of the water column suggests that microbial communities in the lower surface layer may be functionally specialized. Appl Environ Microbiol, 1997 Apr, 63(4), 1375 - 81 Seasonal distributions of dominant 16S rRNA-defined populations in a hot spring microbial mat examined by denaturing gradient gel electrophoresis; Ferris MJ et al.; Denaturing gradient gel electrophoresis analysis of PCR-amplified 16S rRNA gene segments was used to examine the distributions of bacterial populations within a hot spring microbial mat (Octopus Spring, Yellowstone National Park) . Populations at sites along the thermal gradient of the spring's effluent channel were surveyed at seasonal intervals . No shift in the thermal gradient was detected, and populations at spatially or temperature-defined sites exhibited only slight changes over the annual sampling period . A new cyanobacterial 16S rRNA sequence type was detected at temperatures from 63 to 75 degrees C . A new green nonsulfur bacterium-like sequence type was also detected at temperatures from 53 to 62 degrees C . Genetically unique though closely related cyanobacterial and green nonsulfur bacterium-like populations were successively distributed along the thermal gradient of the Octopus Spring effluent channel . At least two cyanobacterial populations were detected at each site; however, a limited ability to detect some cyanobacterial populations suggests that only dominant populations were observed. Appl Environ Microbiol, 1997 Apr, 63(4), 1367 - 74 Population structure and physiological changes within a hot spring microbial mat community following disturbance; Ferris MJ et al.; The influence of disturbance on a hot spring cyanobacterial mat community was investigated by physically removing the top 3.0 mm, which included the entire cyanobacterial layer . Changes in 16S rRNA-defined populations were monitored by denaturing gradient gel electrophoresis analysis of PCR-amplified 16S rRNA gene segments . Some previously absent cyanobacterial populations colonized the disturbed areas, while some populations which were present before the disturbance remained absent for up to 40 days . Changes in physiological activity were measured by oxygen microelectrode analyses and by 14CO2 incorporation into cyanobacterial molecular components . These investigations indicated substantial differences between the disturbed and undisturbed mats, including an unexplained light-induced oxygen consumption in the freshly exposed mat, increased carbon partitioning by phototrophs into growth-related macromolecules, bimodal vertical photosynthesis profiles, and delayed recovery of respiration relative to photosynthesis. Proc Natl Acad Sci U S A, 1997 Apr 1, 94(7), 3284 - 9 Peptide-induced nasal tolerance for a mycobacterial heat shock protein 60 T cell epitope in rats suppresses both adjuvant arthritis and nonmicrobially induced experimental arthritis; Prakken BJ et al.; Adjuvant arthritis (AA) can be induced in Lewis rats by immunization with mycobacterial antigens . Passive transfer of a T cell clone recognizing the 180-188 amino acid sequence in mycobacterial heat shock protein 60 (hsp60) was found to induce AA . In the present study, we investigated whether tolerance was obtained for this AA-associated T cell epitope after intranasal or s.c . administration of a peptide containing this epitope . Two 15-mer peptides containing the mycobacterial hsp60 sequences 176-190 and 211-225 were used; 176-190 contained the T cell epitope 180-188, which was recognized by the arthritogenic T cell clone A2b and was the immunodominant hsp60 T cell epitope after induction of AA, and 211-225 contained a T cell epitope that was recognized both after induction of arthritis with whole Mycobacterium tuberculosis and after immunization with mycobacterial hsp60 . In rats treated intranasally or subcutaneously with 176-190 and immunized with mycobacterial hsp60, proliferative responses to 176-190 were reduced . Proliferative responses to 211-225 and to whole mycobacterial hsp60 were not affected . AA was inhibited intranasally in the 176-190-treated rats but not in the 211-225-treated rats . Moreover, intranasal 176-190 led to similar arthritis-protective effects in a nonmicrobially induced experimental arthritis (avridine-induced arthritis) . Therefore, tolerance for a disease-triggering, microbial cartilage-mimicking epitope may cause resistance to arthritis irrespective of the actual trigger leading to development of the disease. Phytochemistry, 1997 Apr, 44(8), 1479 - 82 Enantioselective accumulation of (--)-pinoresinol through O-demethylation of (+/-)-eudesmin by Aspergillus niger; Kasahara H et al.; Microbial transformation of (+/-)-eudesmin by Aspergillus niger was investigated . Enantioselective accumulation of (--)-pinoresinol was shown through O-demethylation of (+/-)-eudesmin . This fungus O- demethylated both enantiomers of eudesmin, but the conversion rates for each enantiomer were clearly different. Curr Opin Biotechnol, 1997 Apr 1, 8(2), 175 - 80 Developments in metabolic engineering; Cameron DC et al.; The complete sequencing of several microbial genomes has resulted in the increased availability of genes for metabolic engineering . The number of databases and computational tools to deal with this information has also increased . This development has stimulated, and will continue to stimulate, advances in metabolic engineering . Specific recent advances include improvement of pathways for aromatic metabolites, the development of a more complete understanding of the effect of bacterial hemoglobin on cell performance, the development of NMR-based methods for the monitoring of intracellular metabolites and metabolic flux, and the application of metabolic control analysis and metabolic flux analysis to a variety of systems. Eur J Biochem, 1997 Mar 15, 244(3), 858 - 61 Characterization of hexose oxidase from the red seaweed Chondrus crispus; Groen BW et al.; Hexose oxidase from the red seaweed, Chondrus crispus was purified to homogeneity . The enzyme appeared to be encapsulated in particles obtained after mechanical disintegration of the fronds . Liberation of the enzyme in soluble form required either waiting for the spontaneous development of a suitable microbial flora in the suspension, or treatment with a mixture of proteases (pronase) . As deduced from (SDS/)PAGE, the enzyme has a molecular mass of 87 kDa and probably consists of subunits of 36 kDa and 25 kDa . The low isoelectric point of 2.8 and the presence of 25% (by mass) sugars indicate that the enzyme is a strongly acidic glycoprotein . The absorption spectrum of isolated enzyme minus that of the substrate-reduced enzyme, and the EPR spectrum of the free radical observed in the reduced enzyme revealed the presence of a flavin . This cofactor is probably covalently bound since flavins were not released upon denaturation of the enzyme by heat or acid treatment . Taking free FAD as a reference compound, the enzyme contains 1 mol flavin/mol enzyme . EPR spectroscopy of the purified preparation showed the presence of Cu2+ . However, since the amount was substoichiometric, substrate addition did not affect the signal, and the addition of chelator or Cu2+ did not affect the activity, the presence of this metal ion seems adventitious . It is concluded that the large discrepancies between the presently and the previously reported {Sullivan, J . D . & Ikawa, M . (1973) Biochim . Biophys . Acta 309, 11-22} characteristics of the enzyme probably originate from the characterization of a contaminating protein in the latter case. J Pharm Pharmacol, 1997 Mar, 49(3), 263 - 9 Optimization of the chiral inversion of 2-phenylpropionic acid by Verticillium lecanii; Thomason MJ et al.; Previous studies have demonstrated that Verticillium lecanii might be used as a microbial model of the inversion of 2-arylpropionic acids in man . This paper describes the optimization of the inversion process in respect of culture medium, pH, cell density and substrate concentration . The study demonstrates that optimum inversion occurs in Sorensen's phosphate buffer at pH 5.5 . The extent and rate of inversion were also shown to be dependent on substrate concentration and cell density . This study will form the basis of the development of a microbial model of the metabolism of 2-arylpropionic acids which might be suitable for the in-vitro screening of new compounds in this class. Drug Metab Dispos, 1997 Mar, 25(3), 301 - 10 Microbial models of mammalian metabolism . Fungal metabolism of phenolic and nonphenolic p-cymene-related drugs and prodrugs . I . Metabolites of thymoxamine; Moussa C et al.; This study was undertaken to validate the use of microbial biotransformation systems for drug metabolism studies . Thymoxamine 1 was rapidly hydrolyzed to desacetylthymoxamine (DAT) 2 by numerous fungi . Other known animal metabolites, such as N-desmethyl-desacetylthymoxamine 3 and desacetylthymoxamine-O-sulfate 6, were produced from DAT by Mucor rouxii and Mortierella isabellina . DAT-N-oxide 5, a putative animal microsomal metabolite, was also produced by M . isabellina, in addition, a few strains (such as Actinomucor elegans, Mucor hiemalis, and Mucor janssenii) produced a glycosylated metabolite that was identified by high-resolution 1H- and 13C-NMR, MS, and enzymatic hydrolysis as the corresponding {4-(2-dimethylaminoethoxy)-5-isopropyl-2-methyl-phenyl}-1-beta-D- glucopyranoside 7 . A similar glucosylation reaction was observed when thymohydroquinone 10 was incubated with A . elegans . Several strains were able to produce transiently thymohydroquinone from DAT-N-oxide 5, possibly through a beta-elimination mechanism. Ann Periodontol, 1997 Mar, 2(1), 299 - 313 Clinical trials of endosseous implants: issues in analysis and interpretation; Listgarten MA; The majority of contemporary endosseous dental implant systems are based on designs and materials that, over the last three decades, have proved to be predictably reliable . With proper surgical and prosthetic protocols, rates of implant loss have been held to 15% or less over a 5-year period . This information was obtained largely through longitudinal descriptive studies, primarily aimed at obtaining implant survival rates under ideal clinical conditions, with strict inclusion and exclusion criteria for admitting patients into the studies . It is important to emphasize that under conditions of routine clinical practice, where patient selection may be more relaxed than in clinical trials and clinicians attempt to stretch the limits of current technology, the survival rates may not necessarily match those reported in the literature . Since "surviving" implants may exhibit characteristics likely to lead to eventual loss of the implant, for example severe osseous defects, such implants may not necessarily be considered successful . Successful implants should fulfill a list of other criteria considered essential for long-term survival . Differences in implant design preclude some of these criteria from being uniformly applied to all systems . There is a need to identify criteria for success that can be applied to the majority of implant systems . Implants that fail to meet these criteria should be considered failures . Since failure rates may include "failed" as well as "failing" ("ailing") implants, the two categories should be listed separately . From a practical standpoint, implant failures can be grouped into "early" failures, primarily the result of surgical and/or postoperative complications, and "late" failures that arise during and following the restorative phase . The ability of individual systems to achieve excellent success rates, despite some major differences in their design from other systems, suggests that some requirements, initially considered essential for success, may not be as critical as originally believed . Examples include the need for submerging implants during initial wound healing or the need for stress breaking devices . On the other hand, a basic requirement for implant success, such as primary stability at the time of insertion and following loading of the implant, may be the unifying principle behind the need for adequate bone volume and density, longer or wider implants, and the 3 to 6-month delay recommended before implants are placed in function . With relatively low failure rates, a large number of patients may have to be included in long-term clinical trials before a statistically significant association can be established between failure rates and potential contributing factors . For the same reasons, and to avoid type 2 errors, large populations may be needed to show that two systems have comparable success rates . Proving the superiority of one system over another may require fewer subjects . Given the overall low failure rate and the tendency of failures to cluster in individual subjects, failure rates could be markedly affected by the attrition of a few critical subjects . Additional research is needed to validate methods in current use for the clinical determination of osseointegration, and the diagnosis and treatment of occlusal trauma and microbial infections around implants . Also, more reliable methods are needed for the identification of the primary cause(s) of implant morbidity; i.e., infection or occlusal factors. Xenobiotica, 1997 Mar, 27(3), 301 - 15 Fungal transformations of antihistamines: metabolism of cyproheptadine hydrochloride by Cunninghamella elegans; Zhang D et al.; 1 . Metabolites formed during incubation of the antihistamine cyproheptadine hydrochloride with the zygomycete fungus Cunninghamella elegans in liquid culture were determined . The metabolites were isolated by hple and identified by mass spectrometric and proton nmr spectroscopic analysis . Two C elegans strains, ATCC 9245 and ATCC 36112, were screened and both produced essentially identical metabolites . 2 . Within 72 h cyproheptadine was extensively biotransformed to at least eight oxidative phase-I metabolites primarily via aromatic hydroxylation metabolic pathways . Cyproheptadine was biotransformed predominantly to 2-hydroxycyproheptadine . Other metabolites identified were 1- and 3-hydroxycyproheptadine, cyproheptadine 10,11-epoxide, N-desmethylcyproheptadine, N-desmethyl-2-hydroxycyproheptadine, cyproheptadine N-oxide, and 2-hydroxycyproheptadine N-oxide . Although a minor fungal metabolite, cyproheptadine 10,11-epoxide represents the first stable epoxide isolated from the microbial biotransformation of drugs . 3 . The enzymatic mechanism for the formation of the major fungal metabolite, 2-hydroxycyproheptadine, was investigated . The oxygen atom was derived from molecular oxygen as determined from 18O-labelling experiments . The formation of 2-hydroxycyproheptadine was inhibited 35, 70 and 97% by cytochrome P450 inhibitors metyrapone, proadifen and 1-aminobenzotriazole respectively . Cytochrome P450 was detected in the microsomal fractions of C . elegans . In addition, 2-hydroxylase activity was found in cell-free extracts of C . elegans . This activity was inhibited by proadifen and CO, and was inducible by naphthalene . These results are consistent with the fungal epoxidation and hydroxylation reactions being catalysed by cytochrome P450 monooxygenases . 4 . The effects of types of media on the biotransformation of cyproheptadine were investigated . It appears that the glucose level significantly affects the biotransformation rates of cyproheptadine; however it did not change the relative ratios between metabolites produced. Med Hypotheses, 1997 Mar, 48(3), 253 - 9 Superantigens as virulence factors in autoimmunity and immunodeficiency diseases; Soos JM et al.; Virulence factors are microbial products that are known to be harmful to the host and may assist in the pathogenesis of the micro-organism . Superantigens, including those produced by bacteria and viruses, clearly act as virulence factors . The clinical effects of superantigens can be not only acute but also chronic and complex . Recent evidence suggests that superantigens may play a central role in the pathogenesis of autoimmune and immunodeficiency disorders . It is our contention that superantigens, as environmental factors, can change a controllable disease into one that becomes relentless for susceptible individuals . To illustrate the detrimental effects of superantigens on disease outcome, modulation of experimental allergic encephalomyelitis by superantigen, as well as the potential role of superantigens in human immunodeficiency virus pathogenesis will be discussed . The information presented may provide valuable insight into the role of superantigens in autoimmunity and human immunodeficiency virus infection. Int J Sports Med, 1997 Mar, 18 Suppl 1, S46 - 55 Exercise immunology and neutrophils; Smith JA; Neutrophils play important roles in host defense against infectious agents but, paradoxically, they are also involved in the pathology of various inflammatory conditions . Their microbicidal armory consists of oxidative and nonoxidative processes that are activated simultaneously upon phagocytosis . While destruction of infectious agents occurs intracellularly, release of cytotoxic molecules into the extracellular milieu can damage body tissues . Neutrophils are not a homogeneous cell population . Subpopulations exist in various stages from dormant to primed to fully activated . The activities of neutrophils are modulated by cytokines, hormones and bioactive lipids . As neutrophils represent 60% of the circulating leukocyte pool, they are readily accessible to experimental investigation . The sequence of events that occurs in the neutrophil response to microbial invasion includes adherence, chemotaxis, phagocytosis, the oxidative burst, degranulation and microbial killing . In general, high-intensity exercise suppresses most neutrophil functions both acutely and chronically while the effects of moderate exercise have been conflicting . This review will summarize where the field is now and present some suggestions for future research . Emphasis will be placed on resolving conflicting results that may be due to biological and technical variability, and determination of the regulatory events that may mediate exercise-induced changes in neutrophil function. Ecotoxicol Environ Saf, 1997 Mar, 36(2), 162 - 8 Ecological effects assessment of industrial sludge for microarthropods and decomposition in a spruce plantation; Krogh PH et al.; Effects of dried, granulated industrial sludge-containing residues of organic pesticides and precursors were assessed for microarthropod fauna and the decomposition of a spruce forest floor . The investigation was highly realistic, using large plots of about 1/2 ha, and the application was done with professional equipment . The ecological effects of the sludge were compared with the ecological effects of an inorganic fertilizer . Decreases in abundance of the microarthropods ranged from 20 to 80% of the control level after 1 year . Isotoma notabilis Schaffer was the only species that exhibited stimulation at twice the control level due to the sludge . The least affected collembolan species was Lepidocyrtus cyaneus Tullberg, a member of the surface-dwelling life forms . Sensitive species were Isotoma anglicana Lubbock and Isotomiella minor Schaffer . In subhabitats with almost no application of sludge due to a heterogeneous horizontal distribution, the microarthropods were still affected to the same degree as those in the zones of maximum application . Laboratory tests with Folsomia candida Willem gave results similar to the effects on field populations concerning the sludge but revealed no adverse effects of the fertilizer . Decomposition was stimulated to the same extent in the field by the two types of fertilizer but in the laboratory the sludge caused the largest stimulation . The effects on the microarthropod fauna are suggested to be the result of a combination of direct toxicity and changes in the microbial community due to fertilizers. Chest, 1997 Mar, 111(3), 676 - 85 Impact of BAL data on the therapy and outcome of ventilator-associated pneumonia; Luna CM et al.; STUDY OBJECTIVE: To define the impact of BAL data on the selection of antibiotics and the outcomes of patients with ventilator-associated pneumonia (VAP) . DESIGN: Prospective observation and bronchoscopy with BAL, performed within 24 h of establishing a clinical diagnosis of a new episode of hospital-acquired VAP or progression of a prior episode of nosocomial pneumonia (NP) . SETTING: A 15-bed medical and surgical ICU . PATIENTS: One hundred thirty-two patients hospitalized for more than 72 h, who were mechanically ventilated and had a new or progressive lung infiltrate plus at least two of the following three clinical criteria for VAP: abnormal temperature (> 38 degrees C or < 35 degrees C), abnormal leukocyte count (> 10,000/mm3 or < 3,000/mm3), purulent bronchial secretions . INTERVENTIONS: Bronchoscopy with BAL within 24 h of establishing a clinical diagnosis of VAP or progression of an infiltrate due to prior VAP or NP . All patients received antibiotics, 107 prior to bronchoscopy and 25 immediately after bronchoscopy . RESULTS: Sixty-five of the 132 patients were BAL positive (BAL{+}), satisfying a microbiologic definition of VAP (> 10(4) cfu/mL), while 67 were BAL negative (BAL{-}) . The BAL(+) patients had no differences in mortality, prior antibiotic use, and demographic features when compared with the BAL(-) patients . More of the BAL(+) patients (38/65) satisfied all three clinical criteria of VAP than did BAL(-) patients (24/67) (p < 0.05) . A total of 50 BAL(+) patients received antibiotic therapy prior to bronchoscopy, and when this prior therapy was adequate (n = 16), as defined by the results of BAL, then mortality was 38%, while if prior therapy was inadequate (n = 34), mortality was 91% (p < 0.001), and if no therapy was given (n = 15), mortality was 60% . When therapy changes were made after bronchoscopy, more patients (n = 42) received adequate therapy, but mortality in this group was comparable to mortality among those who continued to receive inadequate therapy (n = 23) . A total of 46 of the 65 BAL(+) patients died, with 23 of these deaths occurring during the 48 h after the bronchoscopy, before BAL results were known . When BAL data became available, 37 of the 42 surviving patients received adequate therapy, but their mortality was comparable to the patients who continued to receive inadequate therapy . CONCLUSIONS: Patients with a strong clinical suspicion of VAP have a high mortality rate, regardless of whether BAL cultures confirm the clinical diagnosis of VAP . When adequate antibiotic therapy is initiated very early (ie, before performing bronchoscopy), mortality rate is reduced if this empiric therapy is adequate, compared to when this therapy is inadequate or no therapy is given . If adequate therapy is delayed until bronchoscopy is performed or until BAL results are known, mortality is higher than if it had been given at the time of first establishing a clinical diagnosis of VAP . When patients were changed from inadequate antibiotic therapy to adequate therapy, based on the results of BAL, mortality was comparable to those who continued to receive inadequate therapy . Thus, even if bronchoscopy can accurately define the microbial etiology of VAP, this information becomes available too late to influence survival. J Dent, 1997 Mar, 25(2), 79 - 89 Children, adolescents and periodontal diseases; Dibart S; OBJECTIVES: This manuscript attempts to critically review current literature regarding the natural history, aetiology and pathogenesis of the common periodontal diseases to affect children and adolescents . The logic behind the emergence of a new classification in the early 1990s is explained and potential problems with the interpretation of such systems outlined . DATA SOURCES: The manuscript focuses upon recent developments, reported in the international periodontal literature, aimed at unraveling the molecular basis for this group of diseases . The concept of one disease type progressing with time to another disease within the same individual is discussed, and early data presented that indicate the possibility of microbial transmission from deciduous to permanent dentition's within a subject . CONCLUSIONS: It is concluded that differing classification systems for adolescent and childhood periodontal diseases may lead to confusion within the dental profession, unless the clinical and molecular basis for such diseases is fully understood . Further advances in basic research using molecular biology tools should assist in our understanding of the aetiopathology at a molecular level and hopefully lead to the development of new treatment strategies. J Math Biol, 1997 Mar, 35(4), 453 - 79 Population dynamics and competition in chemostat models with adaptive nutrient uptake; Tang B et al.; The standard Monod model for microbial population dynamics in the chemostat is modified to take into consideration that cells can adapt to the change of nutrient concentration in the chemostat by switching between fast and slow nutrient uptake and growing modes with asymmetric thresholds for transition from one mode to another . This is a generalization of a modified Monod model which considers adaptation by transition between active growing and quiescent cells . Global analysis of the model equations is obtained using the theory of asymptotically autonomous systems . Transient oscillatory population density and hysteresis growth pattern observed experimentally, which do not occur for the standard Monod model, can be explained by such adaptive mechanism of the cells . Competition between two species that can switch between fast and slow nutrient uptake and growing modes is also considered . It is shown that generically there is no coexistence steady state, and only one steady state, corresponding to the survival of at most one species in the chemostat, is a local attractor . Numerical simulations reproduce the qualitative feature of some experimental data which show that the population density of the winning species approaches a positive steady state via transient oscillations while that of the losing species approaches the zero steady state monotonically. J Med Entomol, 1997 Mar, 34(2), 87 - 94 Black fly (Diptera:Simuliidae) salivary secretions: importance in vector competence and disease; Cupp EW et al.; When blood-feeding, black flies introduce secretions into the feeding lesion that act in a coordinated manner on the 3 arms of the vertebrate hemostatic system (platelet aggregation, coagulation, and vasoconstriction) . Apyrase activity inhibits platelet aggregation and is ubiquitous in the saliva of black flies, although activity per gland varies by species and has a positive association with anthropophagy . Anticoagulants target components in the final common pathway of the coagulation cascade, including factors V, Xa, and II (thrombin) . The antithrombin salivary protein may exert a redundant effect by inhibiting the role of thrombin in platelet aggregation . Antithrombin presence and activity also varies among black fly species, and exhibits a positive correlation with zoophagy . Vasodilation of capillaries to increase blood supply to the feeding wound appears to be an important requirement for Simulium spp., because substantial erythema-inducing activity, has been demonstrated in salivary glands of all New World species examined . Salivary glands of Simulium ochraceum (Walker), a highly anthropophilic vector of Onchocerca volvulus (Leuckhart), contain greater vasodilator activity than several other species, including S . metallicum Bellardi, a secondary zoophagic vector of human onchocerciasis . Simulium vittatum Zetterstedt saliva affects immune cell responses and cytokine production . The ability of the saliva to modulate components of the host immune system provides an opportunity for enhancing transmission of pathogens during bloodfeeding . Thus, the likely possibility that effective pathogen transmission relies on vector saliva may complement present efforts aimed at target epitopes of O . volvulus or identify additional molecules to be investigated as part of a "river blindness" vaccine cocktail . Components in saliva also may enhance the transmission of other microbial agents either by a cofeeding process similar to that observed in ixodid ticks or through rupture of the labrum during escape of Onchocerca infective stage larvae . In a few instances, saliva of some Simulium spp . also has been associated with extensive tissue and organ pathology, including hemorrhagic shock and death . Pathologic signs associated with this syndrome indicate an enhanced antihemostatic activity in saliva. Inflamm Res, 1997 Mar, 46(3), 93 - 7 Pulmonary cell infiltration after chronic exposure to (1-->3)-beta-D-glucan and cigarette smoke; Sjostrand M et al.; OBJECTIVE AND DESIGN: To evaluate the effect of a microbial cell wall component--(1-->3)-beta-D-glucan--on the inflammatory effect induced by cigarette smoke in a subchronic exposure situation . MATERIAL: Groups of guinea-pigs were exposed 5 days/week to cigarette smoke, an aerosol of (1-->3)-beta-D-glucan, or to both . METHODS: The numbers of different inflammatory cells were studied in histological sections, enzyme digested lung tissue and in lung lavage . Cell enzyme production was measured . RESULTS: Exposure to (1-->3)-beta-D-glucan or cigarette smoke caused only minor alterations in inflammatory cells . Given together they caused an increase in cellularity in the tissue with significantly increased numbers of macrophages, lymphocytes, neutrophils and eosinophils . There was also an increase in subepithelial eosinophils . Lung lavage cell enzyme production was slightly lower in the combined exposure group . CONCLUSION: The results demonstrate that (1-->3)-beta-D-glucan synergistically increases the inflammation induced by cigarette smoke . The mechanism may be a downregulation of the macrophage control of inflammatory cell migration into the lung tissue. J Clin Pharmacol, 1997 Mar, 37(3), 175 - 8 Relationship between the prescriber's instructions and compliance with antibiotherapy in outpatients treated for an acute infectious disease; Favre O et al.; Antibiotics are frequently prescribed in everyday practice for the management of acute microbial infections . The present study was designed to assess the relationship between the prescriber's instructions and the patient's adherence to a prescribed schedule of twice-daily doses of antibiotic for at least 5 days to treat an infectious disease . The trial was conducted by ten practicing physicians on ambulatory patients . Compliance with the antibiotic regimen was evaluated using a microelectronic device, the Medication Event Monitoring System (MEMS) . Seventy patients were prescribed an antibiotic in twice-daily doses for 5 to 14 days (mean = 8) . Data were available for analysis from 68 of them, aged 18 to 84 years (mean = 44) . The "taking compliance" for the whole story group, which corresponded to the ratio of the number of times the bottle was opened and the total number of doses prescribed during the monitoring period, was nearly perfect at 99.6% . However, only 32.6% of the medications was taken within 1 hour before or after the 12-hour interval expected to be optimal for a twice-daily regimen . It therefore seems highly desirable that physicians give more detailed recommendations to their patients regarding the drug regimens they prescribe. Lipids, 1997 Mar, 32(3), 263 - 71 Differentiation of human promyelocytic leukemia cell line HL60 by microbial extracellular glycolipids; Isoda H et al.; Microbial extracellular glycolipids, succinoyl trehalose lipid (STL), and mannosylerythritol lipid (MEL) inhibited the growth of a human promyelocytic leukemia cell line, HL60, and induced their morphological changes . The results of specific and nonspecific leukocyte esterase activities showed that STL induced monocytotic differentiation while MEL induced granulocytic differentiation . STL and MEL markedly increased common differentiation-associated characteristics in monocytes and granulocytes, such as nitroblue tetrazolium (NBT) reducing ability, expression of Fc receptors, and phagocytic activities in HL60 cells, respectively . Neither sugar moieties nor fatty acids in the free form, the individual components of STL and MEL, were effective at inducing the differentiation of HL60 cells . The induction of differentiation was not due to surface activities of STL and MEL on the basis of the complete ineffectiveness of the analogues tested . The composition of cell surface glycosphingolipids (GSL) changed such that the GM3/LacCer ratio increased in STL-treated cells, whereas it decreased in MEL-treated cells . HL60 cells treated with STL and MEL exhibited a significant decrease in the activity of the intracellular phospholipid- and Ca(2+)-dependent protein kinase (protein kinase C) . Furthermore, the serine/threonine phosphorylations in intact HL60 cells were clearly inhibited by the presence of GM3 and MEL, but not by LacCer and STL . These results suggest that the differentiation-inducing activity of STL and MEL is not due to a simple detergent-like effect but due to a specific action on the plasma membrane . The inhibitory effect of STL on protein kinase activity was through increasing GM3, but MEL had a direct inhibitory effect. Cornea, 1997 Mar, 16(2), 125 - 31 Contact lens-related microbial keratitis: Part I: Epidemiology; Liesegang TJ; PURPOSE: To put into perspective the individual risk and the societal burden of contact lens microbial keratitis . METHODS: I reviewed the available epidemiologic data on contact lens microbial keratitis with emphasis on distinguishing microbial from nonmicrobial keratitis, determining the incidence of the disease, the relative risk with different styles of contact lenses, and the risk factors . RESULTS: Contact lens wear can be classified in multiple different ways (indications for wear, contact lens material, wearing schedule, and replacement schedule) . Adverse effects of contact lens wear on the cornea have been documented by several studies . Distinction between aseptic and septic focal infiltrates is discussed . The incidence rates for bacterial microbial keratitis range from approximately two/10,000 per year for rigid contact lens, 2.2-4.1/10,000 per year for daily-wear soft contact lens, to 13.3-20.9/10,000 per year for extended-wear soft contact lenses . The risk with therapeutic contact lenses is much higher: approximately 52/10,000 per year . Comparative studies suggest that the relative risk of microbial keratitis is approximately 1 for rigid gas-permeable lenses (RGPs; the referent), 0.5-2.74 for polymethylmethacrylate (PMMA), 1.0-4.2 for daily-wear soft contact lenses, 2.7-36.8 for extended-wear soft contact lenses, and 13.0-13.3 for disposable soft contact lens wear . The most significant risk factors include overnight wear, smoking, male sex, and socioeconomic status . CONCLUSIONS: There is a significant health concern for the 26 million wearers of contact lenses with some potentially modifiable risk factors . Identification of the risk factors and further studies of the pathogenesis allow contact lens manufacturers to direct research efforts and practitioners to provide better information and informed consent to patients. FASEB J, 1997 Mar, 11(4), 248 - 55 Sialic acids as ligands in recognition phenomena; Varki A; The sialic acids are acidic monosaccharides typically found at the outermost ends of the sugar chains of animal glycoconjugates . They potentially can inhibit intermolecular and intercellular interactions by virtue of their negative charge . However, they can also act as critical components of ligands recognized by a variety of proteins of animal, plant, and microbial origin (sialic acid binding lectins) . Recognition can be affected by specific structural variations and modifications of sialic acids, their linkage to the underlying sugar chain, the structure of these chains, and the nature of the glycoconjugate to which they are attached . Presented here is a summary of the various proteins that can recognize and bind to this family of monosaccharides, comparing and contrasting the structural requirements and mechanisms involved in binding . Particular attention is focused on the recently evolving information about sialic acid recognition by certain C-type lectins (the selectins), I-type lectins (e.g., CD22 and sialoadhesin), and a complement regulatory protein (the H protein) . The last two instances are examples of the importance of the side chain of sialic acids and the effects of natural substitutions (e.g., 9-O-acetylation) of this part of the molecule. Appl Environ Microbiol, 1997 Mar, 63(3), 1143 - 7 Molecular beacons: trial of a fluorescence-based solution hybridization technique for ecological studies with ruminal bacteria; Schofield P et al.; Molecular beacons are fluorescent probes developed for solution rather than membrane hybridization . We have investigated the utility of these probes to study rumen microbial ecology . Two cellulolytic species, Ruminococcus albus and Fibrobacter succinogenes, were tested . Membrane and solution hybridizations gave similar results in competition experiments with cocultures of R . albus 8 and F . succinogenes S85. Appl Environ Microbiol, 1997 Mar, 63(3), 888 - 95 Plasmids isolated from marine sediment microbial communities contain replication and incompatibility regions unrelated to those of known plasmid groups; Sobecky PA et al.; Two hundred ninety-seven bacteria carrying plasmids that range in size from 5 to 250 kb were identified from more than 1,000 aerobic heterotrophic bacteria isolated from coastal California marine sediments . While some isolates contained numerous (three to five) small (5- to 10-kb) plasmids, the majority of the natural isolates typically contained one large (40- to 100-kb) plasmid . By the method of plasmid isolation used in this study, the frequency of plasmid incidence ranged from 24 to 28% depending on the samples examined . Diversity of the plasmids occurring in the marine sediment bacterial populations was examined at the molecular level by hybridization with 14 different DNA probes specific for the incompatibility and replication (inc/rep) regions of a number of well-characterized plasmid incompatibility groups (repB/O, FIA, FII, FIB, HI1, HI2, I1, L/M, X, N, P, Q, W, and U) . Interestingly, we found no DNA homology between the plasmids isolated from the culturable bacterial population of marine sediments and the replicon probes specific for numerous incompatibility groups developed by Couturier et al . (M . F . Couturier, F . Bex, P . L . Bergquist, and W . K . Maas, Microbiol . Rev . 52:375-395, 1988) . Our findings suggest that plasmids in marine sediment microbial communities contain novel, as-yet-uncharacterized, incompatibility and replication regions and that the present replicon typing system, based primarily on plasmids derived from clinical isolates, may not be representative of the plasmid diversity occurring in some marine environments . Since the vast majority of marine bacteria are not culturable under laboratory conditions, we also screened microbial community DNA for the presence of broad- and narrow-host-range plasmid replication sequences . Although the replication origin of the conjugally promiscuous broad-host-range plasmid RK2 (incP) was not detectable in any of the plasmid-containing culturable marine isolates, DNA extracted from the microbial community and amplified by PCR yielded a positive signal for RK2 oriV replication sequences . The strength of the signal suggests the presence of a low level of the incP replicon within the marine microbial community . In contrast, replication sequences specific for the narrow-host-range plasmid F were not detectable in DNA extracted from marine sediment microbial communities . With the possible exception of mercuric chloride, phenotypic analysis of the 297 plasmid-bearing isolates did not demonstrate a correlation between plasmid content and antibiotic or heavy metal resistance traits. Cancer Res, 1997 Mar 1, 57(5), 812 - 4 Intestinal neoplasia in the ApcMin mouse: independence from the microbial and natural killer (beige locus) status; Dove WF et al.; We have tested the hypothesis that enteric bacteria are necessary for formation of intestinal adenomas in C57BL/6-ApcMin/+ mouse . Germ-free mice developed 2-fold fewer adenomas than conventional controls in the medial small intestine (7.3 versus 14.9; P < 0.003), but there were no significant differences in the rest of the intestinal tract . We conclude that microbial status does not strongly alter the adenoma phenotype in this mouse model of familial adenomatous polyposis . In parallel, we have found that C57BL/6-ApcMin/+ mice mutated at the beige locus, which controls natural killer activity, are also unaltered in adenoma multiplicity. Environ Manage, 1997 Mar, 21(2), 233 - 8 Effects of Recreational Impacts on Soil Microbial Communities ZABINSKI CA, GANNON JE. / The functional diversity of soil microbial communities in heavilyimpacted subalpine campsites and adjacent undisturbed areas was comparedusing the Biolog method of carbon utilization profiles . Principal componentsanalysis of patterns and level of microbial activity indicate that microbialcommunities differentiate in response to disturbance in the top 6 cm of soil,while below 6 cm there were no recognizable differences between disturbed andundisturbed soil communities . Analysis of the factors that differentiate theupper microbial communities between disturbed and undisturbed sites revealedthat the percent of total carbon sources utilized was significantly less inthe disturbed (54%) than in undisturbed areas (95%) . Carbonsubstrates important in the discrimination between soil communities includeplant, invertebrate, and microbial derivatives that could not be metabolizedby microbial communities from disturbed sites . Comparisons of totalculturable actinomycetes, bacteria, and fungi reveal no difference in overallnumber of colony forming units (CFU) on disturbed and undisturbed sites, buta marked decrease in actinomycetes on disturbed sites . Biolog andspread-plate data combined indicate a shift in the structure and function ofthe microbial community in campsite soils, which may be a useful indicator ofsoil community disturbance.KEY WORDS: Microbial functional diversity; Anthropogenic disturbance;Recreational impacts; Carbon source profile; Subalpine Presse Med, 1997 Feb 22, 26(5), 204 - 6 {The concept of reactive arthritis}; Dougados M; More than fifty years after the clinical syndrome was described by Reiter, Fiessinger and Leroy, the diagnostic criteria of what has now been termed reactive arthritis are still under debate . Reactive arthritis can be defined as an aseptic inflammatory joint disease occurring either in a patient with a bacterial infection located in a distant organ or with a particular genetic predisposition . The lack of specific criteria has led to a certain degree of liberty in interpreting the three basic elements of reactive arthritis: clinical presentation, "distant" infection, genetic predisposition . It is generally accepted that limiting the diagnosis of reactive arthritis only to patients with the classic oculo-uretro-synovial manifestations is unsatisfactory . The question remains open as to whether only patients presenting both inflammatory joint disease and spondylarthropathy have reactive arthritis or whether any undetermined etiology of arthritis is sufficient if the patient also has a "distant" infection and a specific genetic predisposition (HLA B27) . Two new elements further complicate the situation . The first is the recent demonstration that the synovial fluid in patients with reactive arthritis might contain microbial antigens . The second is that longterm antibiotics (more than 3 months) could have a beneficial effect . Asking when the diagnosis should be entertained is thus not a moot question . Although we still have no clear answer, it is reasonable to state that the diagnosis of reactive arthritis should be retained only in patients with both inflammatory joint disease and criteria compatible with spondylarthropathy . Clinical research is required to determine whether the germ is actually present or not within the joint and to assess the effect of long-term antibiotherapy. Eur J Pharmacol, 1997 Feb 19, 321(1), 87 - 96 The protective role of thiols against nitric oxide-mediated cytotoxicity in murine macrophage J774 cells; Zamora R et al.; Nitric oxide (NO) plays an important role in the cytotoxic activity of macrophages towards tumour cells and microbial pathogens . We investigated whether alteration of intracellular thiol levels modulates the cytotoxic effects of different NO donors and lipopolysaccharide-induced NO in the murine macrophage cell lin J774A.1 . The NO-releasing compound S-nitroso-N-acetylpenicillamine caused a significant concentration-dependent loss of viability of the macrophages only under glucose-limiting conditions . The cytotoxic effect of S-nitroso-N-acetylpenicillamine was prevented by the NO scavenger 2-(4-carboxyphenyl)-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide (carboxy-PTIO) . Depletion of total glutathione before exposure to S-nitroso-N-acetylpenicillamine further decrease cell viability while pretreatment with N-acetylcysteine was protective . Comparing equimolar concentrations of various NO donors including S-nitrosoglutathione, S-nitrosocysteine and 3-morpholino-sydnonimine hydrochloride, cytotoxicity appeared to be related to the relative stability of the test compound . Both the order of stability and the order of potency for cell killing was S-nitrosoglutathione > S-nitroso-N-acetylpenicillamine > S-nitrosocysteine = 3-morpholino-sydnonimine hydrochloride . Stimulation of the macrophages with lipopolysaccharide and interferon-gamma resulted in dose-dependent cell injury and NO production . Glutathione depletion prior to stimulation considerably decreased macrophage viability as well as the NO production . In contrast to the protective effect on S-nitroso-N-acetylpenicillamine-mediated injury, pretreatment with N-acetylcysteine did not influence the lipopolysaccharide-mediated cytotoxicity . These results demonstrate that (a) reduction in the availability of glucose and intracellular glutathione renders the cells more vulnerable to the cytotoxic effects of NO donors, (b) in this model of cytotoxicity, long-lived NO donors were more cytotoxic than short-lived NO donors, (c) the differential effects of N-acetylcysteine on S-nitroso-N-acetylpenicillamine-induced and bacterial lipopolysaccharide-mediated cytotoxicity support the existence of other toxic species different from NO or NO-related compounds with a potent cytotoxic activity in immunostimulated macrophages, and (d) other non-protein thiols like N-acetylcysteine may substitute for glutathione as a major component of the cellular antioxidant defense system. Proc Natl Acad Sci U S A, 1997 Feb 18, 94(4), 1321 - 6 A genetic system to identify DNA polymerase beta mutator mutants; Washington SL et al.; DNA polymerase beta (pol beta) is a 39-kDa protein that functions in DNA repair processes in mammalian cells . As a first step toward understanding mechanisms of polymerase fidelity, we developed a genetic method t