FEBS Lett, 1990 Feb 26, 261(2), 323 - 6 Ca2(+)-dependent noradrenaline release from permeabilised PC12 cells is blocked by botulinum neurotoxin A or its light chain; McInnes C et al.; Permeabilisation of PC12 cells with digitonin allowed a direct study of the intracellular action of botulinum neurotoxin A, one of a group of dichain proteins produced by Clostridium botulinum that causes the fatal neuroparalytic condition, botulism . Release of {3H}noradrenaline from these permeabilised cells could be evoked by Ca2+ and this was inhibited specifically by the neurotoxin in a dose-dependent manner (half-maximal dose approximately 2 nM under the conditions used) . Inclusion of the reducing agent dithiothreitol (up to 10 mM) had no effect on the level of inhibition . Moreover, electrophoretic analysis showed that this treatment of the toxin in the native state caused negligible reduction of inter-chain disulphide bonds . Toxin-induced blockade of neurotransmitter release was incomplete and could not be overcome by increased Ca2+ concentration (100 microM) . The observed toxin-insensitivity of the release from intact PC12 cells must result from inefficient toxin uptake, relative to that in peripheral cholinergic neurones . Refolded light chain alone inhibited exocytosis to the same degree and with similar potency to that of the intact neurotoxin, an effect not altered by the heavy chain . This inhibitory activity of the light chain in PC12 cells accords with observations made in permeabilised chromaffin cells {(1989) J . Biol . Chem . 264, 10354-10360; (1989) FEBS Lett . 255, 391-394} but contrasts with invertebrate neurones, where intracellular injection of the same preparations of both chains were necessary for inhibition of quantal release of acetylcholine {(1988) Proc . Natl . Acad . Sci . USA 85, 4090-4094} . These collective findings may signify an interesting difference in the release process in such diverse systems or denote a dissimilarity in the transport or processing of the toxin when applied into intact neurones or cells permeabilised by detergent or streptolysin. Carbohydr Res, 1990 Feb 25, 196, 29 - 40 Phase-transfer-catalyzed synthesis of aryl alpha-ketosides of N-acetylneuraminic acid . A 2-methylfluoran-6-yl glycoside of N-acetylneuraminic acid, 2-methyl-6-(5-acetamido-3,5-dideoxy-alpha-D-glycero-D-galacto- nonulopyranosylonic acid)xanthene-9-spiro-1'-isobenzofuran-3'-one, a new substrate for neuraminidase assay; Rothermel J et al.; Glycosidation of N-acetylneuraminic acid by phase-transfer catalysis in chloroform-aqueous alkali gave several known and some new aryl alpha-ketosides in a short reaction time and in good yields . The 4-methylumbelliferyl alpha-ketoside, the standard substrate for neuraminidase, was prepared in a yield of up to 70% . New Neu5Ac ketosides were prepared with fluorescein and the fluorescein analog, 2-methyl-6-hydroxyfluoran (2-methyl-6-hydroxyxanthene-9-spiro-1'-isobenzofuran-3'-one) as aglycons, the latter being synthesized from 2-(2-hydroxy-5-methyl-benzoyl) benzoic acid and 3-fluorophenol . The alpha configuration was ascertained by 400-MHz 1H-n.m.r . spectroscopy and by cleavage of the ketosides with neuraminidases from Vibrio cholerae and Clostridium perfringens . The enzymic hydrolysis of the 2-methylfluoran-6-yl ketoside gave Km values of 82 microM (V . cholerae) and 96 microM (C . perfringens). J Biol Chem, 1990 Feb 25, 265(6), 3124 - 33 Controlled potential enzymology of methyl transfer reactions involved in acetyl-CoA synthesis by CO dehydrogenase and the corrinoid/iron-sulfur protein from Clostridium thermoaceticum; Lu WP et al.; Many anaerobic bacteria fix CO2 via the Wood pathway of acetyl-CoA synthesis . Carbon monoxide dehydrogenase (CODH), also called acetyl-CoA synthase, accepts the methyl group from the methylated corrinoid/iron-sulfur protein (C/Fe-SP), binds a carbonyl group from CO, CO2, or the carboxyl of pyruvate, and binds coenzyme A . Then CODH catalyzes the synthesis of acetyl-CoA from these enzyme-bound groups . Here, we have characterized the methyl transfer steps involved in acetyl-CoA synthesis . We have studied the reactions leading to methylation of CODH by methyl iodide and shown an absolute requirement of the C/Fe-SP in this reaction . In addition, we have discovered and partly characterized two previously unknown exchange reactions catalyzed by CODH: between the methylated C/Fe-SP and methylated CODH and between methylated CODH and the methyl moiety of acetyl-CoA . We have performed these two exchange reactions, methylation of the C/Fe-SP, and methylation of CODH at controlled potentials . The rates of all these reactions except the exchange between methylated C/Fe-SP and methylated CODH are accelerated (from 1 to 2 orders of magnitude) when run at low potentials . Our results provide strong evidence for a nucleophilic redox-active metal center on CODH as the initial acceptor of the methyl group from the methylated C/Fe-SP . This metal center also is proposed to be involved in the cleavage of acetyl-CoA in the reverse reaction. Vet Rec, 1990 Feb 24, 126(8), 191 - 2 Testing strains of Clostridium perfringens type A isolated from diarrhoeic piglets for the presence of the enterotoxin gene; van Damme-Jongsten M et al.; A diarrhoeic syndrome in piglets has been linked to Clostridium perfringens type A because this organism has been isolated in large numbers from all cases . The strains isolated from these cases and strains isolated from healthy piglets were screened for the enterotoxin gene of C perfringens by DNA-hybridisation . Using two different synthetic DNA-probes, none of the strains isolated from diseased pigs was positive in this reaction, indicating that the enterotoxin of C perfringens is not involved in the syndrome. Eur J Biochem, 1990 Feb 22, 188(1), 73 - 82 Chemical characterization of the regularly arranged surface layer glycoprotein of Clostridium thermosaccharolyticum D120-70; Altman E et al.; Clostridium thermosaccharolyticum D120-70 possesses as its outermost cell envelope layer a square-arranged array of glycoprotein molecules . SDS/polyacrylamide gel electrophoresis of the purified surface layer showed a broadened band in the molecular mass range of about 115 kDa which, upon periodic acid/Schiff staining, gave a positive reaction . After proteolytic degradation of this material, two glycopeptide fractions were obtained . One- and two-dimensional nuclear magnetic resonance studies, together with methylation analysis and periodate oxidation, were used to determine the structures of the polysaccharide portions of these glycopeptides . The combined chemical and spectroscopic evidence suggests the following structures: (formula; see text). JAMA, 1990 Feb 16, 263(7), 979 - 82 Inappropriate testing for diarrheal diseases in the hospital; Siegel DL et al.; To assess the degree to which routine stool cultures, ova and parasite examinations, and Clostridium difficile toxin assays may be inappropriately ordered on hospitalized patients, we conducted a retrospective study to determine the relative yield of these tests on specimens collected from outpatients and inpatients as a function of time after admission . During a 3-year period, only 1 of 191 positive stool cultures and none of the 90 ova and parasite examinations with positive results were from the group of patients who had stool specimens submitted after 3 days of hospitalization . Analysis of laboratory work load for a 1-year period showed that specimens from this patient group contributed nearly 50% of the more than 3000 specimens received each year . In contrast, approximately 25% (range, 17% to 33%) of samples, regardless of admission status, were positive for C difficile toxin . Eliminating routine stool cultures and ova and parasite examinations on hospitalized patients would significantly reduce hospital and patient costs without altering patient care . Nationwide, such a policy might achieve a cost savings of +20 to +30 million per year. Eur J Biochem, 1990 Feb 14, 187(3), 521 - 41 A two-dimensional 1H NMR study on Megasphaera elsdenii flavodoxin in the reduced state . Sequential assignments; van Mierlo CP et al.; Assignments for the 137 amino acid residues of Megasphaera elsdenii flavodoxin in the reduced state have been made using the sequential resonance assignment procedure . Several hydroxyl and sulfhydryl protons were observed at 41 degrees C at pH 8.3 . Spin systems were sequentially assigned using phase-sensitive two-dimensional-correlated spectroscopy and phase-sensitive nuclear Overhauser enhancement spectroscopy . Spectra of the protein in H2O and of protein preparations either completely or partly exchanged against 2H2O were obtained . Use of the fast electron shuttle between the paramagnetic semiquinone and the diamagnetic hydroquinone state greatly simplified the NMR spectra, making it possible to assign easily the 1H resonances of amino acid residues located in the immediate neighbourhood of the isoalloxazine ring . The majority of the nuclear Overhauser effect contracts between the flavin and the apoprotein correspond to the crystal structure of the flavin domain of Clostridium MP flavodoxin, but differences are also observed . The assignments provide the basis for the structure determination of M . elsdenii flavodoxin in the reduced state as well as for assigning the resonances of the oxidized flavodoxin. Biochem Biophys Res Commun, 1990 Feb 14, 166(3), 1411 - 20 The isolation and properties of collagenolytic proteases from crab hepatopancreas; Klimova OA et al.; A mixture of collagenolytic proteases has been isolated from the Kamchatka crab hepatopancreas . The four individual enzymes were further separated with FPLC and partially characterized . Crab collagenolytic proteases possess a high activity against different types of collagen, especially against calf skin collagen Type III and bovine lens capsule collagen Type IV, which is resistant to the microbial Clostridium sp . collagenases . In contrast with microbial collagenases the crab enzymes are good general proteases, able to cleave standard synthetic and protein substrates and possess a chymotrypsin-, trypsin- and elastase-like specificity . N-Terminal sequence analysis revealed that crab collagenolytic proteases had evolved from a trypsin-like ancestor . Crab proteases, structurally belonging to the trypsin-like enzymes, nevertheless, possess the unique ability, among this class of enzymes, to cleave the native insoluble collagen . It seems that crab collagenolytic proteases and true metalloenzyme vertebrate and microbial collagenases have certain common structural features particularly in the regions of their substrate binding site. Biochem Biophys Res Commun, 1990 Feb 14, 166(3), 1398 - 405 Multiple small molecular weight guanine nucleotide-binding proteins in human erythrocyte membranes; Damonte G et al.; Native membranes from human erythrocytes contain the following G proteins which are ADP-ribosylated by a number of bacterial toxins: Gi alpha and Go alpha (pertussis toxin), Gs alpha (cholera toxin), and three proteins of 27, 26 and 22 kDa (exoenzyme C3 from Clostridium botulinum) . Three additional C3 substrates (18.5, 16.5 and 14.5 kDa) appeared in conditions of unrestrained proteolysis during hemolysis . SDS-PAGE separation of erythrocyte membrane proteins followed by electroblotting and incubation of nitrocellulose sheets with radiolabeled GTP revealed consistently four GTP-binding proteins with Mr values of 27, 26, 22 and 21 kDa . Although a 22 kDa protein was immunochemically identified as ras p21, the C3 substrate of 22 kDa is a different protein probably identifiable with a rho gene product . Accordingly, at least five distinct small molecular weight guanine nucleotide-binding proteins, whose functions are so far undetermined, are present in native human erythrocyte membranes. BMJ, 1990 Feb 10, 300(6721), 383 - 5 Crisis in our hospital kitchens: ancillary staffing levels during an outbreak of food poisoning in a long stay hospital; Pollock AM et al.; An investigation into an outbreak of food poisoning caused by Clostridium perfringens showed evidence of poor food handling by catering staff . The reasons behind this were explored by interviewing catering staff, analysing shifts and rotas, and looking at staff vacancies . Morale was low because of staff shortages resulting from a long term recruitment problem . In consequence staff were working double shifts and often for weeks on end without a day off . The reasons for the recruitment problem included the difficulty of recruiting semiskilled labour from a middle class area, low wages, lack of management support, and the poor image of the hospital as a place of work . Similar factors affect the recruitment and retention of ancillary staff nationally . The NHS has a poor record as an employer of ancillary staff, paying lower wages than other organisations for equivalent posts . Competitive tendering has further worsened the position of ancillary staff, with the result that good quality of care and service has often not been achieved . The NHS Review, with its emphasis on quality of care, makes no mention of ancillary staff . Yet high standards of ancillary provision are essential if further outbreaks of food poisoning in hospitals are to be prevented. J Infect Dis, 1990 Feb, 161(2), 340 - 2 An international outbreak of type E botulism due to uneviscerated fish; Telzak EE et al.; In October and November 1987, eight cases of type E botulism occurred in New York City and Israel . All eight patients had eaten uneviscerated, salted, air-dried whitefish known as kapchunka . Clostridium botulinum was isolated from samples of fish, and trypsinized portions of kapchunka contained type E toxin despite levels of salt that were far in excess of those considered adequate for safety . As C . botulinum has been found in the viscera of fish from the Great Lakes, possible explanations for the outbreak include multiplication of C . botulinum and production of toxin during shipping or during processing before the fish reached inhibitory salt levels . However, there was no evidence of mishandling of the fish . More likely, the viscera provided a relatively low salt "protective" environment for organism multiplication and toxin production . A major public health campaign was initiated and regulations were passed prohibiting the processing, distribution, and sale of raw, uneviscerated, salt-cured fish products within New York City. Rev Esp Enferm Dig, 1990 Feb, 77(2), 120 - 4 {Low incidence of pseudomembranous colitis associated with antibiotics at a general hospital in Lima}; Sanchez E et al.; Clostridium difficile is associated to episodes of diarrhea related to the use of antibiotics in general hospitals . The aim of this study has been to determine the incidence of this complication among the patients admitted in a 400 bed general hospital in Lima, Peru; we registered every day, in all the wards of the hospital, the presence of diarrhea in patients under antibiotic treatment . In every patient with diarrhea we investigated the presence of cytotoxin and cultivated for C . difficile in the feces . Only 25 patients presented diarrhea and none of them showed inflammatory changes in the endoscopic exploration . Only one patient presented positive cytotoxin with negative culture . In the control group of 41 new-born, asymptomatic infants, already on breast-feeding there were 27 (65.8%) culture and/or cytotoxin positive . We conclude that in our adult population colitis due to C . difficile, associated to antibiotic therapy is an infrequent disease. Anal Biochem, 1990 Feb 1, 184(2), 330 - 7 Synthesis and applications of 8-azido photoaffinity analogs of P1,P3-bis(5'-adenosyl)triphosphate and P1,P4-bis(5'-adenosyl)tetraphosphate; Prescott M et al.; 32P-labeled photoaffinity analogs of bis(5'-adenosyl)-tetraphosphate and bis(5'-adenosyl)triphosphate which contain a single photoreactive 8-azidoadenosine group distal to the radiolabel have been synthesized from commercially available components using a combination of chemical and enzymatic procedures including a water-soluble carbodiimide . The method is simple, rapid, and produces yields of high specific activity products of around 60% . The analog of bis(5'-adenosyl)-tetraphosphate is very similar to the parent compound in its inhibition of rat liver adenosine kinase and its efficiency as a substrate for the bis(5'-nucleosidyl)tetraphosphate pyrophosphohydrolase from Artemia embryos . In the latter case, ATP and 8-azidoAMP are the preferred products . As would be expected, this analog is a much more effective photoprobe for both adenosine and adenylate kinases than the corresponding analog of bis(5'-adenosyl)triphosphate . Both compounds have been used to photoaffinity label crude extracts of Artemia, Vero cells, and Clostridium acetobutylicum and preferential specific labeling of different polypeptides by each analog has been shown . In extracts of C . acetobutylicum, the labeling of a polypeptide of Mr 48,500 by the bis(5'-adenosyl)tetraphosphate analog was totally dependent on the presence of Co2+ ions . These compounds should therefore prove valuable both for the active site labeling of purified binding proteins and for the detection and identification of new target proteins for these nucleotides. J Neurol, 1990 Feb, 237(1), 62 - 3 Polyradiculoneuritis following botulinum toxin therapy; Haug BA et al.; The development of Guillain-Barre syndrome is reported in a patient, who had previously received botulinum toxin type A injections into both orbicularis oculi muscles to treat idiopathic blepharospasm . The possibility of a causal relationship is discussed with consideration of the literature on adverse effects of vaccinations and of Clostridium botulinum and its toxin. Mol Cell Probes, 1990 Feb, 4(1), 1 - 10 Detection of specific antigens for ten serogroups of Clostridium difficile; Delmee M et al.; We previously described a serogrouping technique for Clostridium difficile based on slide agglutination with rabbit antisera raised against formol-treated cells . It allows the differentiation of ten serogroups, namely A, B, C, D, F, G, H, I, K and X . Each serogroup displays a specific profile with several distinctive bands by polyacrylamide gel electrophoresis (PAGE) . In this study we investigated the common and specific antigenic determinants of the ten serogroups by immunoblotting . In a first experiment, whole cell proteins of the ten reference strains were separated by SDS-PAGE, transferred onto nitrocellulose membrane and immunoblotted against their homologous and heterologous antisera . Each serogroup was characterized by several common bands and one or two specific antigens which were proven to correspond to the lowest molecular weight distinctive band observed on PAGE profiles . New rabbit antisera were subsequently raised against the purified specific antigen obtained by electro-elution from polyacrylamide gels . Immunoblots were repeated with these new antisera: all reactions were serogroup specific except one minor cross reaction between C and F . The antisera still agglutinated the homologous strain without any cross agglutination, suggesting that the serogroup specific determinant is a surface antigen responsible for agglutination. Am J Surg, 1990 Feb, 159(2), 212 - 7 Clostridium difficile diarrhea and colonization after treatment with abdominal infection regimens containing clindamycin or metronidazole; Gerding DN et al.; One hundred fifty-six patients with presumed or documented abdominal infections were treated with amikacin/metronidazole/placebo (Group 1, 56 patients), amikacin/clindamycin/placebo (Group 2, 57 patients), or amikacin/clindamycin/ampicillin (Group 3, 43 patients) to determine both the therapeutic efficacy of the various regimens and the type of complications due to Clostridium difficile . C . difficile diarrhea occurred in 15 of 156 patients (9.6%), and C . difficile colonization occurred in 14 of 156 patients (9%) during treatment and 30 days of follow-up . The number of C . difficile diarrhea cases in Group 1 (3 of 56) was significantly lower than in Group 2 (9 of 57, p less than 0.05), but not in Group 3 (3 of 43) . Exclusion of all patients who received other antibiotics in the 30-day poststudy period revealed no C . difficile diarrhea or colonization in Group 1 (0 of 13) and an acquisition rate of 31% (14 of 45) with the regimens containing clindamycin (p less than 0.02) . Successful treatment outcomes (106 evaluable patients) were not statistically different among the three groups (Group 1, 64%; Group 2, 76%; and Group 3, 88%), but these data were difficult to interpret because, by chance, significantly more patients in Group 1 had bacteremia at entry (p less than 0.01), and patients in Group 3 had significantly more biliary tract infections (p less than 0.02) and significantly more favorable acute physiology scores (p less than 0.05) . Use of metronidazole can reduce complications related to C . difficile, particularly if additional antimicrobials other than aminoglycosides are avoided. Am J Med, 1990 Feb, 88(2), 137 - 40 Prospective, controlled study of vinyl glove use to interrupt Clostridium difficile nosocomial transmission; Johnson S et al.; PURPOSE: Despite recognition that Clostridium difficile diarrhea/colitis is a nosocomial infection, the manner in which this organism is transmitted is still not clear . Hands of health care workers have been shown to be contaminated with C . difficile and suggested as a vehicle of transmission . Therefore, we conducted a controlled trial of the use of disposable vinyl gloves by hospital personnel for all body substance contact (prior to the institution of universal body substance precautions) to study its effect on the incidence of C . difficile disease . PATIENTS AND METHODS: The incidence of nosocomial C . difficile diarrhea was monitored by active surveillance for six months before and after an intensive education program regarding glove use on two hospital wards . The interventions included initial and periodic in-services, posters, and placement of boxes of gloves at every patient's bedside . Two comparable wards where no special intervention was instituted served as controls . RESULTS: A decrease in the incidence of C . difficile diarrhea from 7.7 cases/1,000 patient discharges during the six months before intervention to 1.5/1,000 during the six months of intervention on the glove wards was observed (p = 0.015) . No significant change in incidence was observed on the two control wards during the same period (5.7/1,000 versus 4.2/1,000) . Point prevalence of asymptomatic C . difficile carriage was also reduced significantly on the glove wards but not on the control wards after the intervention period (glove wards, 10 of 37 to four of 43, p = 0.029; control wards, five of 30 to five of 49, p = 0.19) . The cost of 61,500 gloves (4,505 gloves/100 patients) used was $2,768 on the glove wards, compared with $1,895 (42,100 gloves; 3,532 gloves/100 patients) on the control wards . CONCLUSIONS: Vinyl glove use was associated with a reduced incidence of C . difficile diarrhea and is indirect evidence for hand carriage as a means of nosocomial C . difficile spread. Obstet Gynecol, 1990 Feb, 75(2), 244 - 8 Microbiologic characteristics of Lactobacillus products used for colonization of the vagina; Hughes VL et al.; Lactobacilli have long been considered to be the protective flora in the vagina . Women with vaginal infections have used various non-prescription products in an attempt to restore their normal vaginal flora . Products that contain lactobacilli include dairy products (yogurt, acidophilus milk) and commercially available Lactobacillus powders and tablets . Recently, Lactobacillus species that produce hydrogen peroxide (H2O2) have been associated with normal vaginal flora . In this study, we compared 16 non-prescription products containing lactobacilli for H2O2 production, purity, and identifiable contaminants . All 16 products contained lactobacilli, of which ten (62%) produced H2O2 . At least one contaminant was detected in 11 of 16 (69%) of the products: Enterococcus faecium (ten), Clostridium sporogenes (one), Streptococcus mitis (one), and Pseudomonas species (one) . Although all of the products tested contained lactobacilli, only four of the products contained Lactobacillus acidophilus . Most of the lactobacilli-containing products currently available either do not contain the Lactobacillus species advertised and/or contain other bacteria of questionable benefit . We conclude that commercially available products may not be appropriate for recolonization of the vagina. Jpn J Med Sci Biol, 1990 Feb, 43(1), 19 - 21 Clostridium botulinum in the soil of Paraguay; Yamakawa K et al.; Seventeen soil samples of Paraguay were examined for the presence of Clostridium botulinum . Botulinum type A, C1 and F toxins were detected in soil cultures . Type E toxin was not detected in any of soil cultures including those from river and lake shores. J Clin Microbiol, 1990 Feb, 28(2), 216 - 9 Klebsiella pneumoniae gastroenteritis masked by Clostridium perfringens; Rennie RP et al.; An unusual food-borne outbreak of gastroenteritis associated with contaminated turkey occurred at a catered company meal . The average incubation period was 10 h, and the predominant symptoms were watery diarrhea and cramps . Vomiting did not occur . Initial epidemiological features and cultures from turkey and feces of infected patients suggested that the causative agent was Clostridium perfringens, but Klebsiella pneumoniae of capsular type K15 was also isolated in large numbers from both the turkey and feces of the same patients . Plasmid analysis and enterotoxin results supported the role of K . pneumoniae as the causative agent in this outbreak . Organisms other than commonly identified pathogens should not be ignored if present in high concentrations in both food and feces of infected persons. Mol Pharmacol, 1990 Feb, 37(2), 278 - 85 N-Methyl-D-aspartate and quisqualate/DL-alpha-amino-3-hydroxy-5- methylisoxazole-4-propionic acid receptors: differential regulation by phospholipase C treatment; Massicotte G et al.; The effect of phospholipase C (PLC) treatment of rat brain membranes on the binding properties of excitatory amino acid receptors was investigated using both a phosphsphatidylcholine-hydrolyzing PLC from Clostridium perfringens and a phosphatidylinositol-specific PLC from Bacillus thuringiensis . PLC from C . perfringens produced an increased affinity of the quisqualate/DL-alpha-amino-3-hydroxy-5-methylisoxazole-4-propionic acid (AMPA) receptor for its ligand, whereas kainate receptor binding was not affected . Both kinetic analysis and equilibrium saturation experiments indicated that PLC treatment produced a decrease in affinity for {3H}N-(1-{thienyl}cyclohexyl)-piperidine {( 3H}TCP), a ligand for the N-methyl-D-aspartate (NMDA) receptor-associated ionic channel, when the channel was fully activated by high concentrations of glutamate and glycine but increased its binding under conditions in which the channel was presumably closed . This latter component of the binding was not due to an interaction of {3H}TCP with non-glutamate receptor sites, such as sigma opioid and histamine H3 receptors . Binding of {3H}glutamate and {3H} glycine to the NMDA receptors was not modified by PLC treatment, but there was a large decrease in the binding of the NMDA antagonist {3H}3-{(+/-)-2-carboxypiperazine-4-yl)propyl-1-phosphonic acid . Stimulation by glycine of {3H}glutamate binding was also abolished following PLC treatment . In contrast to PLC from C . perfringens, phosphatidylinositol-specific PLC treatment did not detectably modify the binding properties of the quisqualate/AMPA receptor or the NMDA receptor channel . These data indicate that alterations in the lipid microenvironment of the glutamate receptors modulate both the conformation and the function of the receptors and suggest a possible role for phospholipases in the regulation of synaptic transmission at excitatory synapses. Singapore Med J, 1990 Feb, 31(1), 56 - 8 In vitro activity of teicoplanin, vancomycin, A16686, clindamycin, erythromycin and fusidic acid against anaerobic bacteria; Hassan H et al.; The in vitro activity of teicoplanin and A16686, two new glycopeptide antibiotics was determined against 196 isolates of anaerobic bacteria . The activity of teicoplanin and A16686, in comparison with that of vancomycin, clindamycin, erythromycin and fusidic acid was 2 to 16 times higher against the gram positive anaerobes, namely, Propionibacterium acnes, Clostridium perfringens, Clostridium difficile, Clostridium species, Peptococcus species and Peptostreptococcus species . However, Bacteroides fragilis was resistant to teicoplanin and A16686 while Bacteroides melaninogenicus and Bacteroides bivius were found to be sensitive. Ann Med, 1990 Feb, 22(1), 37 - 41 Lactic acid bacteria and human health; Gorbach SL; Although claims for health and nutritional benefits have been made for lactic acid bacteria in fermented dairy products for nearly a century, the nutritional and therapeutic value of these organisms is still controversial . This article will review the scientific basis of these claims . There are numerous studies showing fermentation of food with lactobacilli increase the quantity, availability, digestibility, and assimilability of nutrients . The basis for this conclusion comes from direct measurements of vitamin synthesis and from increased feed efficiency when fermented products are fed to animals . There have been a number of studies showing that various fermented dairy products lower serum cholesterol levels in humans and animals . These studies are reviewed and the validity of these findings are assessed . A summary of the evidence indicating that lactase deficient individuals can eat yogurt and the mechanisms involved in this toleration is reviewed . The role of fermented dairy products in inhibiting tumor growth and chemically induced tumors in animals is discussed and the possible mechanisms involved in this protective effect are reviewed . Fermented dairy products and lypholized lactobacilli preparations have been shown to be useful in treating and preventing various intestinal infections including; salmonellosis, shigellosis and antibiotic induced diarrhea . In this context a specific lactobacillus designated GG has been shown to be useful in treating recurring diarrhea caused by a toxin produced by Clostridium difficile. Epidemiol Infect, 1990 Feb, 104(1), 87 - 100 Bacteriological quality of on-farm manufactured goat cheese; Tham WA et al.; The bacteriological quality of 198 ripened soft or semi-soft goat cheeses obtained from dairy farms and the retail trade was investigated . The cheeses were examined for total counts of aerobic bacteria, coliform bacteria (37 and 44 degrees C respectively), enterococci, coagulase positive staphylococci, Bacillus cereus and Clostridium perfringens . Cheeses obtained from dairy-farms were also determined for pH value . In terms of all tests performed, cheeses made of heat-treated milk with starter culture had the best prospects for fulfilling the criteria for 'fit for consumption' . Cheeses made of raw milk without starter culture made up the most unsatisfactory group from a food-hygiene point of view . Bacteriological guidelines for on-farm manufactured goat cheese are suggested. Infect Immun, 1990 Feb, 58(2), 480 - 8 Molecular characterization of the Clostridium difficile toxin A gene; Dove CH et al.; The gene encoding the toxin A protein of Clostridium difficile (strain VPI 10463) was cloned and sequenced . The coding region of 8,133 base pairs had a mol% G + C of 26.9 and encodes 2,710 amino acids . The deduced polypeptide has a molecular mass of ca . 308 kilodaltons . Nearly a third of the gene, at the 3' end, consists of 38 repeating sequences . The repeating units were grouped into two classes, I and II, on the basis of length and the low levels of DNA sequence similarities between them . There were seven class I repeating units, each containing 90 nucleotides, and 31 class II units, which, with two exceptions, were either 60 or 63 nucleotides in length . On the basis of DNA sequence similarities, the class II repeating units were further segregated into subclasses: 7 class IIA, 13 class IIB, 5 class IIC, and 6 class IID . The dipeptide tyrosine-phenylalanine was found in all 38 repeating units, and other amino acid sequences were unique to a specific class or subclass . This region of the protein has epitopes for the monoclonal antibody PCG-4 and includes the binding region for the Gal alpha 1-3Gal beta 1-4GlcNAc carbohydrate receptor . Located 1,350 base pairs upstream from the toxin A translation start site is the 3' end of the toxin B gene . Between the two toxin genes is a small open reading frame, which encodes a deduced polypeptide of ca . 16 or 19 kilodaltons . The role of this open reading frame is unknown. J Lab Clin Med, 1990 Feb, 115(2), 190 - 5 Comparative efficacy of cefoperazone, cefoperazone plus sulbactam, ciprofloxacin, clindamycin, metronidazole, and penicillin G against anaerobic bacteria in an animal model; Moody JA et al.; Treatment efficacy of various antimicrobial regimens against anaerobes was studied in semipermeable chambers simulating a closed-space, locally neutropenic infection site in rabbits . Bacteroides fragilis, Bacteroides melaninogenicus, Clostridium perfringens, and Peptostreptococcus anaerobius were inoculated (at a mean of 5.3 log10 CFU/ml in prereduced pooled rabbit serum) into the chambers (one isolate per chamber) in triplicate . Antimicrobial therapy consisted of cefoperazone, cefoperazone plus sulbactam, ciprofloxacin, clindamycin, metronidazole (against the gram-negative anaerobes), or penicillin G (against the gram-positive anaerobes), beginning 4 hours after organism inoculation and continuing every 6 hours for 16 doses . With the use of anaerobic techniques for specimen acquisition, transport, and culture, quantitative bacterial findings were measured at the start of therapy and at various time points thereafter . Antibiotic concentrations were measured in blood and chamber fluid by liquid chromatography or bioassay methods . At the end of the study in vivo organisms were reduced by at least 3 log10 CFU/ml from drug-free growth control chambers by all the antimicrobial regimens tested except for cefoperazone against B . fragilis and ciprofloxacin against the three isolates tested . The addition of sulbactam to cefoperazone inhibited B . fragilis beta-lactamase activity and eradicated B . fragilis in vivo . In vivo results with this model confirmed in vitro susceptibilities of all tested antimicrobials except ciprofloxacin and should provide useful indications of the potential clinical efficacy of other new agents against anaerobes. J Bacteriol, 1990 Feb, 172(2), 997 - 1004 Purification and characterization of fatty acid beta-oxidation enzymes from Caulobacter crescentus; O'Connell MA et al.; Acetoacetyl coenzyme A (acetoacetyl-CoA) thiolase, an enzyme required for short-chain fatty acid degradation, has been purified to near homogeneity from Caulobacter crescentus . The relative heat stability of this enzyme allowed it to be separated from beta-ketoacyl-CoA thiolase . The purification scheme minus the heating step also permitted the copurification of crotonase and 3-hydroxyacyl-CoA dehydrogenase . These activities are in a multienzyme complex in Escherichia coli, but a similar complex was not observed in C . crescentus . Instead, separate proteins differing in enzymatic activity were detected, analogous to the beta-oxidation enzymes that have been isolated from Clostridium acetobutylicum and from mitochondria of higher eucaryotes . In these cells, as appears to be the case with C . crescentus, the individual enzymes form multimers of identical subunits. Agric Biol Chem, 1990 Feb, 54(2), 437 - 41 Construction of shuttle vector plasmid between Clostridium acetobutylicum and Escherichia coli; Yoshino S et al.; A high copy number plasmid pCS86 (3.0 kb) was isolated from Clostridium acetobutylicum strain No . 86 . For developing the vector plasmid for gene cloning of saccharolytic clostridia, two hybrid plasmids were constructed by joining pCS86 to the E . coli promoter probe vector pKK232-8 carrying the promoterless gene of chloramphenicol acetyltransferase (CAT) . One of the hybrid plasmids designated as pTY10 replicated and expressed the CAT gene in E . coli, and transformed a plasmid-free strain, C . acetobutylicum strain No . 220, as a shuttle vector . This is the first shuttle vector constructed from C . acetobutylicum and E . coli plasmids . Reciprocal transformation was possible between E . coli and C . acetobutylicum, though deletion occurred in the sequence originated from pKK232-8 . A deleted plasmid pTY101 only replicated in Clostridium, though it showed a high copy number. FEMS Microbiol Lett, 1990 Jan 15, 55(1-2), 73 - 7 Biotransformations of aromatic aldehydes by acetogenic bacteria; Lux MF et al.; Vanillin was subject to O demethylation and supported growth of Clostridium formicoaceticum and Clostridium thermoaceticum . Vanillin was also stimulatory to the CO-dependent growth of Peptostreptococcus productus . The aldehyde substituent of vanillin was metabolized by routes which were dependent upon both the acetogen and a co-metabolizable substrate (e.g . carbon monoxide {CO}) . C . formicoaceticum and C . thermoaceticum oxidized the aldehyde group of vanillin to the carboxyl level, while P . productus reduced the aldehyde group of vanillin to the alcohol level . In contrast, during CO-dependent growth, C . thermoaceticum reduced 4-hydroxybenzaldehyde to 4-hydroxybenzyl alcohol while P . productus both reduced and oxidized 4-hydroxybenzaldehyde to 4-hydroxybenzyl alcohol and 4-hydroxybenzoate, respectively . These metabolic potentials indicate aromatic aldehydes may affect the flow of reductant during acetogenesis. Biochem Biophys Res Commun, 1990 Jan 15, 166(1), 126 - 32 Substrate competition and specificity at the active site of amylopullulanase from Clostridium thermohydrosulfuricum; Mathupala S et al.; A highly thermostable pullulanase purified from Clostridium thermohydrosulfuricum strain 39E displayed dual activity with respect to glycosidic bond cleavage . The enzyme cleaved alpha-1,6 bonds in pullulan, while it showed alpha-1,4 activity against malto-oligosaccharides . Kinetic analysis of the purified enzyme in a system which contained both pullulan and amylose as the two competing substrates were used to distinguish the dual specificity of the enzyme from the single substrate specificity known for pullulanases and alpha-amylases. Biochemistry, 1990 Jan 9, 29(1), 132 - 9 Cloning, sequencing, expression, and site-directed mutagenesis of the gene from Clostridium perfringens encoding pyruvoyl-dependent histidine decarboxylase; van Poelje PD et al.; The DNA encoding pyruvoyl-dependent histidine decarboxylase (HisDCase) of Clostridium perfringens was cloned, sequenced, and overexpressed in Escherichia coli . The gene encodes a single polypeptide of 320 amino acids, Mr 35,526, demonstrating that clostridial HisDCase, which has an (alpha beta)6 structure, is synthesized as a precursor (proHisDCase, pi 6) . No pi subunits of proHisDCase were observed in crude or purified preparations of the cloned HisDCase; they appear to undergo rapid cleavage in vivo to the alpha (Mr 24,887) and beta (Mr 10,526) subunits characteristic of this HisDCase . This cleavage occurs between Ser-96 and Ser-97; Ser-97 gives rise to the catalytically essential pyruvoyl group blocking the N-termini of the alpha subunits of the active enzyme . When Ser-97 was converted to an alanyl residue by site-specific mutagenesis, the expressed, inactive protein (pi' 6) contained a single peptide species (pi', Mr 35,510) that was not cleaved either in vivo or in vitro . These results support previous conclusions that activation of the wild-type clostridial proenzyme occurs via nonhydrolytic serinolysis . Although clostridial HisDCase has only a 47% sequence similarity to HisDCase from Lactobacillus 30a, all of the residues known to be important for substrate binding and catalytic action of the Lactobacillus HisDCase are conserved in the C . perfringens enzyme . While the encoded N-terminal Met of clostridial HisDCase is removed by E . coli, the cloned enzyme retains a 10-residue presequence (NKNLEANRNR) not present in the mature enzyme isolated from C . perfringens. Rev Infect Dis, 1990 Jan-Feb, 12 Suppl 2, S243 - 51 Clostridium difficile: clinical considerations; Bartlett JG; Clostridium difficile was originally reported as an agent of enteric disease in 1977 . Subsequent work has shown this organism to be what many consider the most important bacterial pathogen of the gut in developed countries in terms of severity of disease and prevalence . A review of the literature indicates that almost all of the clinically relevant data for this organism were reported by 1981, including data on the spectrum of disease, clinical settings in which it is suspect, epidemiology, pathophysiologic mechanisms, distinction between toxin A and toxin B, diagnostic tests, and therapeutic guidelines . This report reviews the historical data that led to the discovery of C . difficile, current information that is clinically relevant, and remaining issues of concern as a guide for future studies. Rev Infect Dis, 1990 Jan-Feb, 12 Suppl 2, S231 - 4 Resistance to beta-lactam antibiotics in anaerobic bacteria; Nord CE et al.; The known mechanisms of beta-lactam resistance in anaerobic bacteria involve production of beta-lactamases, alteration of penicillin-binding proteins, and blocked penetration of beta-lactam antibiotics through bacterial outer membranes . The most important factor in beta-lactam resistance is production of beta-lactamases, which have been found in various Bacteroides, Fusobacterium, and Clostridium species . beta-Lactam resistance in Bacteroides fragilis is commonly mediated by beta-lactamases that are mainly cephalosporinase in character . B . fragilis strains can also produce penicillinases and enzymes inactivating cefoxitin and imipenem . The non-fragilis species of Bacteroides produce beta-lactamases that are mainly penicillinase in character . Penicillinases are also isolated from Fusobacterium nucleatum . Among the clostridia, Clostridium butyricum, Clostridium clostridioforme, and Clostridium ramosum have been shown to produce penicillinases. Rev Infect Dis, 1990 Jan-Feb, 12 Suppl 2, S185 - 91 Virulence factors of Clostridium difficile; Borriello SP et al.; In addition to the two major toxins of Clostridium difficile--toxins A and B, which represent the major virulence factors--a number of other putative virulence factors have been described . These factors include fimbriae and the ability to associate with gut cells/mucus, the production of a capsule, the secretion of a range of hydrolytic enzymes, the production of other toxins (such as an actin-specific ADP-ribosyltransferase by some strains), and the controversial possibility of the production of a second enterotoxin . The extent to which these additional putative virulence factors are involved in the pathogenesis of C . difficile-related gut disease remains to be elucidated. Am J Surg Pathol, 1990 Jan, 14(1), 87 - 92 The colonic pathology of Escherichia coli O157:H7 infection; Kelly J et al.; We report the colonic pathology of two surgical excisions and two autopsies from patients acutely infected by E . coli O157:H7 . The right colon was most severely affected . Extreme edema, fibrin deposition, and hemorrhage in the submucosa was the most distinctive finding . All cases showed patchy mucosal ulceration, mucosal hemorrhage, neutrophil infiltration, and microvascular thrombi . Pseudomembranous lesions similar to those described in pseudomembranous colitis caused by Clostridium difficile were a minor feature . Advanced lesions displayed regenerative mucosal changes and heavy plasmacytic infiltration of submucosa . The colonic pathology may be due to bacterial verocytotoxin rather than to bacterial attachment-effacement or invasion. Zentralbl Mikrobiol, 1990, 145(4), 269 - 75 {The refining of liquid swine manure as a substrate for biotechnologic transformation processes}; Marx R et al.; Pure and mixed cultures of Clostridium Spec . were tested in sterile and nonsterile batch fermentations in order to increase the content of short chain fatty acid in different liquid swine manure substrates . Fatty acid concentrations of 15 g/l were reached by a thermochemical pretreatment of the substrates and the application of a mixed culture of Cl . acetobutylicum, Cl . butyricum and Cl . paraputrificum . The distributions of C2-C5 fatty acids were determined . The results represent the basis to intensify the process of the biotechnological conversion of liquid swine manure. Klin Khir, 1990, (6), 35 - 6 {Antibacterial activity of nitazole and its use in combined treatment of appendicular peritonitis in children}; Topuzov VS et al.; The experimental-clinical investigations have demonstrated the high effectiveness of the native preparation Nitazole against the Gram-negative non-spore-forming anaerobic bacteria, Gram-positive anaerobic cocci, spore-forming Clostridium, certain facultative anaerobes . This permits to recommend it for the use as an antibacterial preparation for the treatment of peritonitis in children. Schweiz Arch Tierheilkd, 1990, 132(5), 239 - 45 {A case of disseminated intravascular coagulation (DIC) in a cow with endometritis and fetal death}; Braun U et al.; Acute disseminated intravascular coagulation (DIC) was diagnosed in a 3 1/2 year old cow of the Simmental breed . The cow was little less than 6 months pregnant and was admitted to the clinic because of severely disturbed general health . The most important clinical findings were increased heart and breathing rate, rectal temperature of 39.9 degrees C, nosebleed and petechiae on the nasal mucosa . Additionally, the cow showed petechiae on the vaginal mucosa, haemorrhage from the rectum lasting several hours after rectal examination and severe haemoglobinuria . Haematological and biochemical examinations showed increased liver enzymes and severe changes in all coagulation parameters (platelet count, PT, PTT, thrombin time, fibrinogen, fibrin degradation products) . Based on the mentioned findings the diagnosis DIC was made . Possible causes were severe necrotic endometritis and placentitis combined with fetal death . High counts of Escherichia coli and Clostridium perfringens were determined in liver, lung and abomasal contents of the aborted fetus as well as in the placenta . Uterine secretion contained Actinomyces pyogenes besides. J Indian Med Assoc, 1990 Jan, 88(1), 8 - 10 Clinicobacteriological study of gas gangrene; Udgaonkar US et al.; Out of 1040 cases of road side crush injuries 14 cases (1.3%) who developed gas gangrene clinically were studied bacteriologically . Clostridia accounted for 6 (42.86%) cases and non-clostridial anaerobes and aerobes for 4 (28.57%) cases each . Clostridium perfringens was found to be the commonest isolate but non-clostridial anaerobes and aerobes also formed a sizable number . It was concluded that for prevention of gas gangrene a proper surgical toilet and antibiotics at the time of injury were necessary and a smear examination might give a clue to early diagnosis. Biochem Cell Biol, 1990 Jan, 68(1), 225 - 30 Phosphatidylglycerol acetal of plasmenylethanolamine as an intermediate in ether lipid formation in Clostridium butyricum; MacDonald DL et al.; The formation and turnover of the recently discovered phosphatidylglycerol acetal of plasmenylethanolamine was investigated in Clostridium butyricum . Incorporation of phosphate into the phospholipids was studied by using {32P}orthophosphate in pulse and pulse-chase experiments in growing cells . Among the ethanolamine-containing lipids, the diacyl form of phosphatidylethanolamine was labeled most rapidly, followed by the phosphatidylglycerol acetal of plasmenylethanolamine and plasmenylethanolamine . The glycerol acetal of plasmenylethanolamine was labeled most slowly . There was rapid turnover of approximately one half of the newly labeled phosphatidylethanolamine pool . Since the kinetics of labeling of the small pool of phosphatidylglycerol acetal of plasmenylethanolamine and the larger pool of plasmenylethanolamine were similar during the early time courses of pulse and pulse-chase experiments, the results argue against the derivation of phosphatidylglycerol acetal of plasmenylethanolamine from plasmenylethanolamine . The results are consistent with the derivation of glycerol acetal of plasmenylethanolamine from either phosphatidylglycerol acetal of plasmenylethanolamine or plasmenylethanolamine. Toxicon, 1990, 28(4), 411 - 8 Contraction induced by Clostridium perfringens alpha toxin in the isolated rat ileum; Sakurai J et al.; Clostridium perfringens alpha toxin caused contraction of the isolated rat ileum in a dose-dependent manner . The contraction caused by the toxin was inhibited by verapamil, nifedipine, cinnarizine, but not by tetrodotoxin or incubation in a low Na+ medium . The toxin stimulated Ca2+ uptake in the ileum in a dose-dependent manner . Nifedipine completely inhibited the Ca2+ uptake into the ileum induced by the toxin . Furthermore, TMB-8, trifluoperazine, W-7 and H-7 significantly blocked the toxin-induced contraction . On the other hand, the toxin activated de novo production of phosphatidic acid and phosphatidylinositol in the tissue . These data suggest that the toxin-induced contraction is due to an increased Ca2+ permeability across the tissue, and activation of phospholipid metabolism. Diagn Microbiol Infect Dis, 1990 Jan-Feb, 13(1), 57 - 61 In vitro activity of meropenem (SM-7338), imipenem, and five other antibiotics against anaerobic clinical isolates; Murray PR et al.; The in vitro susceptibility of 513 recent anaerobic clinical isolates was evaluated against meropenem (SM-7338), a new carbapenem, and six other antibiotics . Virtually all Gram-positive and Gram-negative anaerobic bacteria tested were susceptible to meropenem (defined as MICs less than or equal to 8 micrograms/ml) with 99.8% of the isolates inhibited by less than or equal to 4 micrograms/ml . The activity of meropenem was comparable to imipenem for most clinical isolates . Minor differences were observed for Clostridium and Veillonella (meropenem more active) and other Gram-positive bacilli (imipenem more active) . Meropenem inhibited all anaerobes resistant to clindamycin and metronidazole . Bactericidal tests performed with meropenem demonstrated killing activity against all isolates except Clostridium and Lactobacillus. Microbiol Immunol, 1990, 34(1), 55 - 64 Demonstration of a surface antigen of Clostridium tyrobutyricum by use of immunoblotting with a monoclonal antibody; Gueguen F et al.; A monoclonal antibody, prepared against whole cells of Clostridium tyrobutyricum, recognized a surface antigen extracted by heat treatment or by hot phenol-water treatment . This antigen, after analysis by polyacrylamide gel electrophoresis and immunoblotting, has been shown to present a regularly-spaced ladder pattern similar to those shown by the lipopolysaccharide of many gram-negative bacteria . The proteinase K has been shown to have no effect on the recognition of this epitope by the monoclonal antibody . On the contrary, the inhibition of the antigen reactivity to the monoclonal antibody after a mild periodate oxidation suggests the involvement of a carbohydrate moiety in the epitope . Moreover, the SDS-PAGE analysis of phenol-water extracts has shown an additional compound, detected by silver staining but not recognized by the monoclonal antibody. FEMS Microbiol Lett, 1990 Jan 1, 54(1-3), 323 - 6 Lysogenic phages of Clostridium perfringens: mapping of the chromosomal attachment sites; Canard B et al.; The sites of insertion for two lysogenic bacteriophages have been mapped on the chromosome of Clostridium perfringens strain CPN50 using two techniques based on pulsed field gel electrophoresis . Phage phi 29 was mapped to the 1 Mb region of the 3.6 Mb genome, near nanH which encodes a potential virulence factor, while phi 59 was found to have inserted at 2.9 Mb. Acta Chir Scand, 1990 Jan, 156(1), 105 - 10 The significance of timing of metronidazole prophylaxis and addition of fosfomycin in colorectal surgery . An experimental study in rats; Kling PA et al.; A novel approach to antibiotic prophylaxis in colonic surgery, suggested by our previous clinical experience, was experimentally tested . Intravenous administration of metronidazole or fosfomycin at greater than or equal to 4 hours before surgery effectively prevented lethal infectious complications, whereas metronidazole prophylaxis begun at induction of anaesthesia proved to be much less efficacious (4% and 43% deaths vs . 50% among controls, p less than 0.001 and p greater than 0.7, respectively) . The in vivo efficacy of antibiotic prophylaxis correlated better with mucosal counts of Clostridium and Bacteroides than with luminal counts of aerobic or anaerobic bacteria . Earlier initiation of intravenous metronidazole prophylaxis thus markedly increased its in vivo efficacy, apparently due to preoperative mucosal suppression of endogenous potential pathogens . This 'early timing' approach to systemic prophylaxis against infection in abdominal surgery warrants further evaluation both for other antibiotics and clinically. Thorax, 1990 Jan, 45(1), 72 - 3 Necrotising pneumonia and empyema due to Clostridium perfringens complicating pulmonary embolus; Bashir Y et al.; A fatal case of necrotising pneumonia due to Clostridium perfringens developing as a complication of pulmonary infarction is reported. Poult Sci, 1990 Jan, 69(1), 119 - 23 Influence of neuraminidase on fertility and on sperm storage in the hen's oviduct; Howarth B Jr; Preinsemination incubation of semen with neuraminidase (4 IU/2 x 10(9) spermatozoa) significantly reduced fertility in one out of two trials . No differences were observed in fertility between semen treated with 4 versus 8 or 4 versus 16 IU of neuraminidase in Trials 1 or 2 . All three levels of neuraminidase (4, 8, or 16 IU) removed the same amount (about 45%) of the bound sialic acids from spermatozoa during incubation . The removal of sialic acid from spermatozoa had a slight but nonsignificant affect on sperm storage within the uterovaginal (UV) sperm-host glands . Hens inseminated with neuraminidase-treated spermatozoa had decreased numbers of full and partially full UV sperm-host glands and increased numbers of empty glands, compared to hens inseminated with untreated but incubated spermatozoa . In the present study, reduced fertility resulting from the treatment of spermatozoa with neuraminidase from Clostridium perfringens indicates the desirability of exploring the use of other neuraminidases to see whether a correlation exists between the amount of sialic acid removed from spermatozoa and their subsequent fertility. Biologicals, 1990 Jan, 18(1), 49 - 54 The development of an enzyme-linked immunosorbent assay for measuring the potency of vaccines containing Clostridium chauvoei antigens; Crichton R et al.; Current standards (British Pharmacopeia (Veterinary) 1985) for vaccines containing Clostridium chauvoei require a potency test based on a challenge assay in guinea-pigs . Animal welfare and cost considerations favour the development of alternatives . Most veterinary clostridial vaccines are multi component, requiring assays in rabbits to test the potency of components other than C . chauvoei . We describe the application of an ELISA to measure the response to C . chauvoei vaccines in rabbits . The antigen is a sonicated extract of C . chauvoei strain CH4, intended to include a mixture of cellular and soluble antigens . The rabbit response to more than 70 vaccines containing C . chauvoei has been assessed against a reference serum which has been assigned an arbitrary potency of 100 units ml-1 . The antibody titres of rabbit sera have been compared with the results of guinea-pig challenge potency tests on the same vaccines . The pass level in the guinea-pig potency test is equivalent to a rabbit ELISA titre of 50 units ml-1. Chemotherapy, 1990, 36(2), 127 - 35 Comparative in vitro bactericidal activity of 24 antimicrobial drugs against Clostridium perfringens; Traub WH; Twenty-four antimicrobial drugs were examined for rapidity of onset and magnitude of bactericidal activity against selected strains of Clostridium perfringens . Ceftriaxone, imipenem, metronidazole, mezlocillin, penicillin G, piperacillin, and teicoplanin reduced colony counts by at least 3 log10 units within 2-4 h after exposure . Clindamycin, fluoroquinolones, josamycin, and tetracycline caused delayed kill (greater than or equal to 99.9% reduction of viable counts at 4-22 h after exposure) . Chloramphenicol and rifampin lacked bactericidal activity against 2 of 4 strains, whereas erythromycin, fusidic acid, and fosfomycin (with added glucose-6-phosphate) were merely inhibitory for all 4 strains . Imipenem and penicillin G were combined with 9 and 12 antimicrobial drugs, respectively . Essentially all drug combinations yielded indifferent effects; only penicillin G plus doxycycline resulted in an antagonistic effect against C . perfringens. Appl Environ Microbiol, 1990 Jan, 56(1), 81 - 6 Differential effects of sodium on hydrogen- and glucose-dependent growth of the acetogenic bacterium Acetogenium kivui; Yang HC et al.; Acetogenium kivui could not be revived or maintained in a sodium-deficient medium (0.2 mM sodium) under H2-dependent conditions, and neither lithium nor potassium replaced the sodium requirement of H2-cultivated cells . Conversely, the revival and maintenance of glucose-cultivated cells did not display a dependency on supplemental sodium . In the absence of growth, formate became a major end product in both sodium-deficient and metabolically impaired H2-grown cultures of A . kivui . Harmaline, a putative inhibitor of Na+/H+ antiporters, uncoupled acetogenesis from H2-dependent growth but was less effective when growth was at the expense of glucose . Significantly, carbon monoxide (CO) stimulated H2-dependent growth of A . kivui but inhibited glucose-dependent growth . Collectively, these findings demonstrate that sodium plays a critical role in the H2-dependent bioenergetics of A . kivui and indicate that autotrophic and heterotrophic cells may utilize dissimilar mechanisms of energy conservation . In contrast to the growth of A . kivui, supplemental sodium was not required for the glucose-, H2-, and CO-dependent growth of Clostridium thermoaceticum. Tijdschr Diergeneeskd, 1990 Jan 1, 115(1), 27 - 9 {Rhodococcus equi infection in a goat}; Moraal SA et al.; Enterotoxaemia caused by Clostridium perfringens was diagnosed in a goat affected with severe enteritis which was found to be present at autopsy . Lesions bearing a resemblance to tuberculosis, caused by a Rhodococcus equi infection, were observed in the liver and lungs . This bacterium is constantly isolated from pulmonary abscesses in foals affected with pyemia . Similar cases of infection in goats were previously reported in the literature. Rev Infect Dis, 1990 Jan-Feb, 12 Suppl 2, S152 - 6 Anaerobic bacteria and bacterial infections: perspectives on treatment and resistance in Italy; Panichi G et al.; Results of laboratory tests of 2,000 samples obtained from 1984 to 1987 from patients with suspected anaerobic infections and the clinical experience of these patients are reported . Of these samples, 395 were positive for anaerobes; 36.5% of these 395 samples contained single organisms, and 63.5% contained a mixture of anaerobes and aerobes . Abdominal infections were the infections most frequently caused by anaerobes . The Bacteroides fragilis group and strains of Peptostreptococcus were the microorganisms most frequently isolated . In addition, 300 anaerobes isolated from clinical samples at three Italian hospitals were tested for susceptibility to 10 antibiotics (aztreonam, cefotaxime, cefoxitin, ceftazidime, ceftriaxone, clindamycin, imipenem, metronidazole, penicillin, and piperacillin) . Imipenem and metronidazole proved to be the most active agents, with low and similar values for the 50% and 90% minimal inhibitory concentrations (MICs) . No microorganism showed resistance to these agents . After imipenem and metronidazole, clindamycin was the most effective agent tested . All other antibiotics tested showed elevated MICs against Bacteroides species and Clostridium difficile . In Italy, cefoxitin still maintains satisfactory activity against the majority of anaerobes tested. Rev Infect Dis, 1990 Jan-Feb, 12 Suppl 1, S9 - 10 In vitro antibacterial activity of bismuth subsalicylate; Cornick NA et al.; This study was undertaken to determine the in vitro activity of bismuth subsalicylate (BSS) and sodium salicylate (SS) against various groups of pathogenic bacteria . BSS had the greatest activity against Clostridium difficile, which had a minimal inhibitory concentration for 90% of the strains (MIC90) of 128 micrograms/mL . The Bacteroides fragilis group also had a relatively low MIC90 of 512 micrograms/mL . BSS had the least activity against Pseudomonas (MIC90, 6,144 micrograms/mL) . SS was as active as BSS against aerobic bacteria but was less active against anaerobic bacteria . The MIC90 values of SS for C . difficile and the B . fragilis group were greater than 8,192 and 4,096 micrograms/mL, respectively . This study demonstrates that BSS has antibacterial activity in vitro at levels that should be achievable in the gastrointestinal tract. Rev Infect Dis, 1990 Jan-Feb, 12 Suppl 1, S57 - 8 Effect of bismuth subsalicylate on Clostridium difficile colitis in hamsters; Chang TW et al.; The therapeutic effect of bismuth subsalicylate (BSS, Pepto-Bismol) in Clostridium difficile colitis was studied in golden Syrian hamsters . C . difficile was fed to the hamsters by orogastric intubation 2-3 days after their arrival . Clindamycin (1.5 mg per animal) was given intraperitoneally 4 days later . Twenty-four hours after challenge with clindamycin, animals were given BSS at dosages of 5, 10, and 15 mg twice daily for 5 days by orogastric intubation . Controls included untreated animals and those given 5 mg of vancomycin once daily by intubation . Delay in the time of death was observed in all BSS-treated animals and was statistically significant on days 4-6 in those receiving 15 mg twice daily . Vancomycin produced a greater delay in death than did BSS . Our study suggests that BSS at a dosage of 15 mg twice daily has some therapeutic effect on C . difficile colitis in hamsters. Eur J Clin Microbiol Infect Dis, 1990 Jan, 9(1), 40 - 2 A cluster of seven cases of Clostridium tertium septicemia in neutropenic patients; Valtonen M et al.; A cluster of seven febrile and severely neutropenic patients who developed Clostridium tertium septicemia during a 13-month period is described . The patients had received third generation cephalosporins for 7 to 13 days (mean 9 days) at the time Clostridium tertium was isolated from blood cultures . Two patients had perirectal and one patient pericaecal cellulitis . The organism was also isolated from bronchial secretions in one patient . No patient had diarrhea . Five of six strains tested were resistant to clindamycin (MIC 2-8 micrograms/ml), and six of seven strains moderately resistant to penicillin (MIC 1-4 micrograms/ml) . In one patient Clostridium tertium grew from blood cultures although metronidazole had been administered for two days . Six patients recovered on antibiotic therapy . In view of the unusual susceptibility pattern of Clostridium tertium, an accurate diagnosis of infection with this organism is important for the choice of an appropriate antimicrobial treatment. Biochem J, 1990 Jan 1, 265(1), 261 - 5 Calcium-binding affinity and calcium-enhanced activity of Clostridium thermocellum endoglucanase D; Chauvaux S et al.; Clostridium thermocellum endoglucanase D (EC 3.2.1.4: EGD), which is encoded by the celD gene, was found to bind Ca2+ with an association constant of 2.03 x 10(6) M-1 . Ca2+ stimulated the activity of EGD towards swollen Avicel by 2-fold . In the presence of Ca2+, the Kd of the enzyme towards p-nitrophenyl-beta-D-cellobioside and carboxymethylcellulose was decreased by 4-fold . Furthermore, Ca2+ increased the half-life of the enzyme at 75 degrees C from 13 to 47 min . Since the 3' sequence of celD encodes a duplicated region sharing similarities with the Ca2+-binding site of several Ca2+-binding proteins, a deleted clone was constructed and used to purify a truncated form of the enzyme which no longer contained the duplicated region . The truncated enzyme was very similar to EGD expressed from the intact gene with respect to activity, Ca2(+)-binding kinetics and Ca2+ effects on substrate binding and thermostability . Thus the latter parameters do not appear to be mediated through the duplicated conserved region. J Clin Microbiol, 1990 Jan, 28(1), 131 - 3 Synthetic DNA probes for detection of enterotoxigenic Clostridium perfringens strains isolated from outbreaks of food poisoning; Van Damme-Jongsten M et al.; Four synthetic oligonucleotides encoding different parts of the Clostridium perfringens enterotoxin gene were used to test the enterotoxigenicity of C . perfringens strains isolated from confirmed outbreaks of food poisoning . Of the 245 strains isolated from food and feces originating from 186 separate outbreaks, 145 (59%) gave hybridization reactions with each of the four DNA probes used, while 104 strains did not hybridize with any of the probes . There was no correlation between serotype and the presence of the enterotoxin gene, although the C . perfringens enterotoxin gene was rarely detected among nontypable strains (17%) . Results show that DNA hybridization is a suitable method for the identification of C . perfringens strains which have the potential to produce enterotoxin. J Bacteriol, 1990 Jan, 172(1), 243 - 51 Purification and comparative studies of dihydrolipoamide dehydrogenases from the anaerobic, glycine-utilizing bacteria Peptostreptococcus glycinophilus, Clostridium cylindrosporum, and Clostridium sporogenes; Dietrichs D et al.; Three different dihydrolipoamide dehydrogenases were purified to homogenity from the anaerobic glycine-utilizing bacteria Clostridium cylindrosporum, Clostridium sporogenes, and Peptostreptococcus glycinophilus, and their basic properties were determined . The enzyme isolated from P . glycinophilus showed the properties typical of dihydrolipoamide dehydrogenases: it was a dimer with a subunit molecular mass of 53,000 and contained 1 mol of flavin adenine dinucleotide and 2 redox-active sulfhydryl groups per subunit . Only NADH was active as a coenzyme for reduction of lipoamide . Spectra of the oxidized enzyme exhibited maxima at 230, 270, 353, and 453 nm, with shoulders at 370, 425, and 485 nm . The dihydrolipoamide dehydrogenases of C . cylindrosporum and C . sporogenes were very similar in their structural properties to the enzyme of P . glycinophilus except for their coenzyme specificity . The enzyme of C . cylindrosporum used NAD(H) as well as NADP(H), whereas the enzyme of C . sporogenes reacted only with NADP(H), and no reaction could be detected with NAD(H) . Antibodies raised against the dihydrolipoamide dehydrogenase of C . cylindrosporum reacted with extracts of Clostridium acidiurici, Clostridium purinolyticum, and Eubacterium angustum, whereas antibodies raised against the enzymes of P . glycinophilus and C . sporogenes showed no cross-reaction with extracts from 42 organisms tested. Surg Endosc, 1990, 4(4), 217 - 9 Pseudomembranous colitis: how useful is endoscopy? Bergstein JM, Kramer A, Wittman DH, Aprahamian C, Quebbeman EJ. Clostridium difficile colitis may be diagnosed either by endoscopy or by laboratory tests . To determine the role of endoscopy, we reviewed 59 cases of confirmed C . difficile colitis . In all patients, the etiology was confirmed by stool tests . Twenty-nine underwent lower gastrointestinal endoscopy . In 16 (55%) there was endoscopic confirmation of pseudomembranes while 4 (14%) had only nonspecific colitis . There was no apparent difference in the rate of detection of pseudomembranes between rigid sigmoidoscopy (57%), flexible sigmoidoscopy (50%), and colonoscopy (50%) . Vancomycin and metronidazole were equally effective therapy but treatment with vancomycin cost more than 250 times that for metronidazole . There were no patients in whom the diagnosis was made by endoscopy alone . Endoscopy was costly and insensitive, while noninvasive stool tests were cheap and accurate . We conclude that endoscopy should be relegated to a secondary role in the workup of antibiotic-associated diarrhea. Mikrobiyol Bul, 1990 Jan, 24(1), 66 - 70 {Two treated cases of botulism}; Isik N et al.; Botulism is a severe neuroparalytic disease caused by the neurotoxins of Clostridium botulinum which exert their effects on peripheral nerve junctions . Guillain-Barre syndrome, Myasthenia Gravis, acute Poliomyelitis and diphtheria must be considered in the differential diagnosis . In this study we have discussed two patients who were treated in our clinic, the differential diagnosis and the role of anti-Cholinesterase drugs in the treatment. Rev Inst Med Trop Sao Paulo, 1990 Jan-Feb, 32(1), 6 - 10 {Bacterial flora of the oral cavity, fangs and venom of Bothrops jararaca: possible source of infection at the site of bite}; Jorge MT et al.; Culture of fang, fang sheath and venom of fifteen healthy freshly captured Bothrops jararaca were analyzed . The bacteria most frequently encountered were group D streptococci (12 snakes), Enterobacter sp . (6), Providencia rettgeri (6), Providencia sp . (4), Escherichia coli (4), Morganella morganii (3) and Clostridium sp . (5) . The bacteria observed are similar to those found in the abscesses from Bothrops bitten patients . Since these snake mouth bacteria may be inoculated during the snake bite, bacterial multiplication and infection may occur under favorable conditions. Arch Microbiol, 1990, 154(5), 443 - 7 Repression of toxin production by tryptophan in Clostridium botulinum type E; Leyer GJ et al.; Of the seven amino acids required by Clostridium botulinum type E, tryptophan is the most essential and may provide the cell with nitrogen . The addition of excess tryptophan (10-20 mM) or other nitrogenous nutrients to minimal growth medium markedly decreased toxin formation but did not affect growth in C . botulinum type E . On the other hand, the addition of an enzymatic digest of casein (NZ Case) stimulated toxin formation and overcame repression by tryptophan . Immunoblots of proteins in culture fluids using antibodies to type E toxin indicated that tryptophan-repressed cultures produced less neurotoxin protein . Inhibitors of neurotoxin did not accumulate in cultures grown in minimal medium supplemented with high tryptophan . The results suggest that tryptophan availability in foods or in the intestine may be important for toxin formation by C . botulinum type E. Arch Microbiol, 1990, 154(4), 362 - 9 The biotin-dependent sodium ion pump glutaconyl-CoA decarboxylase from Fusobacterium nucleatum (subsp . nucleatum) . Comparison with the glutaconyl-CoA decarboxylases from gram-positive bacteria; Beatrix B et al.; Membrane preparations of Fusobacterium nucleatum grown on glutamate contain glutaconyl-CoA decarboxylase at a high specific activity (13.8 nkat/mg protein) . The enzyme was solubilized with 2% Triton X-100 in 0.5 M NaCl and purified 63-fold to a specific activity of 870 nkat/mg by affinity chromatography on monomeric avidin-Sepharose . The activity of the decarboxylase was strictly dependent on Na+ (Km = 3 mM) and was stimulated up to 3-fold by phospholipids . The glutaconyl-CoA decarboxylases from the gram-positive bacteria Acidaminococcus fermentans and Clostridium symbiosum have a lower apparent Km for Na+ (1 mM) and were not stimulated by phospholipids . In addition only the fusobacterial decarboxylase required sodium ion for stability and was inactivated by potassium ion . By incorporation of this purified enzyme into phospholipids an electrogenic sodium ion pump was reconstituted . The enzyme consists of four subunits, alpha (m = 65 kDa), beta (33 kDa), gamma (19 kDa), and delta (16 kDa) with the functions of a carboxy transferase (alpha), a carboxy lyase (beta and probably delta) and a biotin carrier (gamma) . The subunits are very similar to those of the glutaconyl-CoA decarboxylases from the gram-positive bacteria . With an antiserum directed against the decarboxylase from A . fermentans the alpha- and the biotin containing subunits of the three decarboxylases and that from Peptostreptococcus asaccharolyticus could be detected on Western blots. Arch Microbiol, 1990, 154(4), 342 - 8 Clostridium homopropionicum sp . nov., a new strict anaerobe growing with 2-, 3-, or 4-hydroxybutyrate; Dorner C et al.; From anoxic sewage sludge a new strictly anaerobic, spore-forming bacterium was isolated with 2-hydroxybutyrate as sole substrate . 2-, 3-, and 4-hydroxybutyrate, 4-chlorobutyrate, crotonate, vinylacetate, and pyruvate were fermented to acetate and butyrate . Fructose was converted to acetate, butyrate, butanol, and H2 . Lactate and acrylate were fermented to acetate and propionate . Cells pregrown with lactate fermented 2-hydroxybutyrate to butyrate, propionate and acetate . No inorganic electron acceptors were reduced . The DNA base ratio was 32.0 +/- 1.0 mol% and was similar to that of Clostridium propionicum, which was determined to be 35.3 +/- 0.5 mol% . Strain LuHBu1 is described as type strain of a new species, Clostridium homopropionicum sp . nov . Another isolate obtained from marine sediment degraded 2- and 3-hydroxybutyrate to acetate and butyrate and was in some respects similar to the known species Ilyobacter polytropus. Prep Biochem, 1990, 20(2), 179 - 85 Biosynthetic preparation of {riboflavin-2-14C}flavin adenine dinucleotide using Clostridium kluyveri; Baldwin JE et al.; The biosynthetic preparation of {riboflavin-2-(14)C}flavin adenine dinucleotide from extracellular {2-(14)C}riboflavin by a growing culture of Clostridium kluyveri, first reported by Decker and coworkers, has been implemented using new media and more convenient isolation procedures. Nephron, 1990, 55(3), 329 - 31 Necrotizing myositis secondary to Serratia marcescens in a renal allograft recipient; Pascual J et al.; We describe a fatal case of spontaneous necrotizing myositis due to a highly resistant strain of Serratia marcescens in a renal transplant recipient . Though Staphylococcus aureus and Clostridium are the usual agents which cause either pyomyositis or necrotizing myositis, gram-negative bacteria are a dangerous and rarely suspected possibility . Such an aggressive disease should be promptly recognized because immunosuppression in susceptible hosts makes conservative management unsuccessful . The prognosis for myositis in immunodepressed hosts is poor and wide excision of all the necrotic muscles, leaving the wound open, and intensive antibiotic therapy are required. Ann N Y Acad Sci, 1990, 589, 67 - 81 Methods for cloning key primary metabolic enzymes and ancillary proteins associated with the acetone-butanol fermentation of Clostridium acetobutylicum; Cary JW et al.; The unavailability of genetically defined mutants for complementation has intensified the problems inherent in cloning genes from C . acetobutylicum . The uniqueness of some of the pathways of this organism coupled with the relative inefficiency of transformation of clostridia and few characterized mutants in these pathways have made cloning these genes by traditional complementation methods impractical . Oligonucleotide hybridization techniques have been shown to circumvent many problems involved in detecting protein expression . The ease of hybridization screening of plaques allows phage libraries to be examined more readily than is generally the case with colony screening techniques . Recombinant lambda phages also contain more DNA per insert than most plasmid vectors can maintain, thus further decreasing the amount of screening necessary . Cosmid libraries, offering even greater length of individual inserts, can be screened in a similar manner, although such screening incorporates the limitations of colony screening techniques . It is true that the technique hinges on the ability to obtain an amino acid sequence from which an oligonucleotide can be designed . In the past, the ability to obtain sequences was limited because the quantity and number of purified proteins were limited or the proteins were amino-terminally blocked . However, recent technological advances in this area, such as high-resolution gel separation techniques coupled with microsequencing, have opened the door to proteins previously inaccessible . Deformylation methods have been developed to deblock amino-terminally formylated proteins, and successful internal amino acid sequence analysis by in situ protease digestion has also been reported using only picomolar quantities of proteins separated by one- or two-dimensional gel electrophoresis . Protein and DNA sequence data banks have been significantly upgraded in the past few years . A proposed oligonucleotide sequence can be evaluated to determine what other possible sequences have similar homology; moreover, protein similarity comparisons between related species might possibly supplant the need for protein isolation if regions of highly conserved amino acid sequences are found . To our knowledge, this represents the first reported use of oligonucleotide probe hybridization screening technology as a strategy for cloning solvent pathway genes of C . acetobutylicum . Despite the deleterious effects on hybridization inherent in the high A + T content of C . acetobutylicum gene specific-directed oligonucleotides, the technique has been shown to function with few modifications to previously recorded systems. Clin Ther, 1990 Jan-Feb, 12(1), 61 - 70 Multicenter in vitro comparison of piperacillin and nine other antibacterials against 1,629 clinical isolates; Greenberg RN et al.; The antibacterial spectrum of activity of piperacillin was compared with that of other antibiotics against isolates of Escherichia coli, Enterobacter cloacae, Haemophilus influenzae, Klebsiella pneumoniae, Pseudomonas aeruginosa, Pseudomonas cepacia, Pseudomonas maltophilia, Serratia marcescens, Enterococcus sp, Bacteroides fragilis, Bacteroides bivius, and Clostridium difficile obtained from laboratories at hospitals in St . Louis, in Memphis, and in Newark, New Jersey . Of the 1,629 isolates tested, 91% were susceptible to piperacillin, 90% to mezlocillin, 87% to ticarcillin/clavulanate and imipenem, 83% to ceftazidime, 81% to cefoperazone, 80% to ciprofloxacin, 77% to ceftriaxone, 71% to aztreonam, and 51% to cefoxitin. FEMS Microbiol Lett, 1990 Jan 1, 54(1-3), 221 - 6 Plasmid transformation of Clostridium perfringens by electroporation methods; Phillips-Jones MK; Two electroporation methods were compared and modified to improve the frequencies of transfer of plasmid DNA into Clostridium perfringens . A plasmid shuttle vector, pSB92A2, containing chloramphenicol and ampicillin resistance genes and a clostridial origin of replication isolated from a cryptic C . perfringens plasmid, was constructed and successfully introduced into C . perfringens by both electrotransformation methods . Modifications which improved frequencies by 15-28 fold are described and may improve frequencies sufficiently for some vector/host combinations to consider the future use of more direct cloning strategies for the clostridia. J Antimicrob Chemother, 1990 Jan, 25(1), 15 - 23 Reduction of 2-, 4- and 5-nitroimidazole drugs by hydrogenase 1 in Clostridium pasteurianum; Church DL et al.; Highly-purified bidirectional hydrogenase (hydrogenase 1) of Clostridium pasteurianum could rapidly reduce several 2-, 4- and 5-nitroimidazole compounds via an electron carrier-coupled mechanism . Hydrogenase 1 was also shown to reduce a 2-nitroimidazole (misonidazole) and a 4-nitroimidazole in the presence of its required electron carriers including ferredoxin, the flavin coenzymes FAD and FMN, and the low potential electron carrier dyes methyl- and benzyl-viologen . No drug reduction by hydrogenase 1 occurred when any one of these electron carriers was replaced by nicotinamide electron carriers (NAD and NADP), or was omitted from the reaction mixture . The rates of reduction of the nitroimidazole compounds correlated with their one electron reduction potentials at pH 7(E7(1)); the higher the drug's E7(1), the faster its rate of reduction by the enzyme . Reduction rates for the drugs did not correlate with the antibacterial activity of these compounds against C . pasteurianum, suggesting that other factors are also important in determining the antimicrobial potencies of nitroimidazoles. Arch Exp Veterinarmed, 1990, 44(2), 205 - 12 Application of microbiological cancer test to cattle infected with bovine leucosis virus; Wittmann W et al.; A microbiological cancer test, previously verified in men and dogs using a clostridium strain (Clostridium butyricum CNRZ 528), was applied to cattle infected with bovine leucosis virus (BLV) . An extended period of time was allowed to pass after infection with BLV, which had been checked up through specific serological and virological examinations . The cattle belonged to different age groups and stages of infection (with and without haematological alterations {preleukosis}, with incipient tumour development {swelling of externally visible and palpable lymph nodes}) . Controls included BLV-infected cows as well as test animals to which isotonic saline had been applied or healthy BLV-free cattle in which the clostridium strain had been used . The serological investigation was carried out in a blind test . 3 of 6 BLV-infected spore-treated heads of cattle responded positively to the cancer test, while the other 3 were negative . The 3 cows with positive cancer test were haematologically and serologically leucosis-positive animals with clinically detectable enlargement of lymph nodes . The 3 negative ones of this group, also serologically and haematologically leucosis-positive, were younger animals without signs of tumorous process . 3 spore-treated BLV-free cows and 2 BLV-infected animals, treated with isotonic saline, were cancer test-negative, as well . Finally, 4 BLV-infected and 2 BLV-free cattle, all of them without spore injection, were completely cancer test-negative . 1 cow of the BLV-infected group did not produce spore antibodies after spore treatment, while 1 cow of the BLV-free untreated control group developed spore antibodies. Rev Chir Orthop Reparatrice Appar Mot, 1990, 76(4), 280 - 3 {Atypical osteogenesis following multiple sequestrectomies for infected open fracture of the femur: a case}; Chevalley F et al.; The authors present the case of an open fracture of femur Cauchoix type II with an infection due to Escherichia coli, Clostridium perfringens, Enterococcus and Aspergillus fumigatus . After several sequestrectomies and five hyperbaric sessions, apyrexia was attained at the end of the third month, the femur having been stabilised with an external fixator . The 15 cm gap due to loss of bone substance, filled at each dressing with an antiseptic iodine based ointment, closed itself finishing as continuous bone five months after the accident, the granulation tissue having been recovered by thin skin grafts . A repeated fracture occurring forty-eight hours after the removal of the Hoffmann frame was treated by fitting an Ilizarov fixator arriving at consolidation in seven months . The authors examine different possibilities of accelerating osteogenesis and highlight the potential role of iodine ointment as inductive to osteogenesis stemming from a periosteal layer seemingly held in place. Glycoconj J, 1990, 7(4), 349 - 54 New ganglioside analogs that inhibit influenza virus sialidase; Suzuki Y et al.; Synthetic thioglycoside-analogs of gangliosides such as Neu5Ac alpha(2-S-6)Glc beta(1-1)Ceramide (1) and the GM3 analog Neu5Ac alpha(2-S-6)Gal beta(1-4)Glc beta(1-1)Ceramide (2), competitively inhibited GM3 hydrolysis by the sialidase of different subtypes of human and animal influenza viruses with an apparent Ki value of 2.8 x 10(-6) and 1.5 x 10(-5) M, respectively . The inhibitory activity of the ganglioside GM4 analog {Neu5Ac alpha(2-S-6)Gal beta(1-1)Ceramide (3)}, in which the glucose of 1 was substituted by galactose, was lower than that of 1 (Ki = 1.0 x 10(-4) M) . The thioglycoside-analogs (1, 2, 3) of the gangliosides were non-hydrolyzable substrates for influenza virus sialidase . The inhibitory activity of 1 to bacterial sialidases from Clostridium perfringens and Arthrobacter ureafaciens was considerably lower than that to influenza virus sialidase, indicating that the structure of the active site in bacterial and influenza virus sialidase may be different and the analogs may be useful to determine the orientation of the substrate to the active site of sialidases, especially of influenza viruses. Dakar Med, 1990, 35(2), 198 - 204 {Tetanus after intramuscular injection in an infectious disease service in Dakar . 12-year review (1978-1989)}; Sow S et al.; Tetanus is a serious toxic-infection common to men and animals produced by a strict anaerobic bacillus: Clostridium Tetani or Nicolaier's Bacillus . It is an infectious, non-contagious, non-immunizing illness, which must be officially notified . Although Tetanus has been known from antiquity and a very efficient specific vaccine is available, in developing countries its frequency and high mortality make it a major problem for Public Health authorities . This dramatic situation in underdeveloped countries is due to: inadequate vaccination and health education; poor infrastructure in health services; the persistence of harmful traditional practices; and disregard for elementary principles of antiseptics and sterilization, leading to the terrible form of tetanus after-muscular injection, a real "tragedy" according to Bourgeade . The aim of this study is to draw attention to the frequency, seriousness and hopeless prognostic of this type of tetanus, all of which could be avoided if simple, elementary, prophylactic measures, such as rigorous disinfection and adequate sterilization of equipment, were undertaken. G Batteriol Virol Immunol, 1990 Jan-Dec, 83(1-12), 88 - 93 {Immunogenic activity of a polyvalent oral vaccine}; Stivala F et al.; The AA . studied the effects of a polyvalent oral vaccine on the cellular immunity, and on IgA level in animal . They also studied its ability to reactivate the response to the Clostridium tetani toxin in human volunteers . The results show a very good ability of the vaccine as specific and aspecific stimulator. J Physiol (Paris), 1990, 84(4), 267 - 72 ADP-ribosylation of the rho/rac gene products by botulinum ADP-ribosyltransferase: identity of the enzyme and effects on protein and cell functions; Narumiya S et al.; 1 . Botulinum C1 toxin and C3 exoenzyme were purified from the culture filtrate of type C Clostridium botulinum strain 003-9, and specific antibodies were raised against each protein . Immunochemical analysis using these antibodies revealed the presence of minute amount of a C3-like molecule in C1 toxin preparation which tightly binds to the toxin component(s) . This enzyme complex was separated from the major neurotoxin . Thus, the ADP-ribosyltransferases in C1 and D toxins and C3 exoenzyme appear to come from the same origin, and should be called together botulinum C3 enzyme . 2 . Botulinum C3 enzyme ADP-ribosylates the rho and rac gene products, a family of small molecular weight GTP-binding proteins homologous to ras p21s . This ADP-ribosylation occurs at Asn41 of the rho products which is located in their putative effector domain, suggesting that it interferes interaction of these GTP binding proteins with their effector molecules . 3 . When incubated with PC-12 cells, the enzyme inhibits cell growth and induces neurites and acetylcholine esterase . Several lines of evidence suggest that the ADP-ribosylation of the rho/rac proteins is responsible for these changes. Crit Rev Food Sci Nutr, 1990, 29(5), 301 - 31 Modified atmosphere packaging of seafood; Stammen K et al.; The shelf life of seafood under current icing and refrigerated storage conditions ranges from 2 to 14 d, depending on species, harvest location, and season . Elevated carbon dioxide levels in modified atmosphere packaging (MAP) has been shown to inhibit the normal spoilage flora of seafood and double or triple shelf life . The threat of botulism, due to the presence of nonproteolytic psychyrotrophic Clostridium botulinum types B, E, and F, has been reason for caution in expanding this technology . This article examines the safety of MAP seafood through analysis and comparison of raw materials, research methodologies, quality indices, treatment, and packaging options. J Bacteriol, 1990 Jan, 172(1), 212 - 7 Biotransformations of carboxylated aromatic compounds by the acetogen Clostridium thermoaceticum: generation of growth-supportive CO2 equivalents under CO2-limited conditions; Hsu T et al.; Clostridium thermoaceticum ATCC 39073 converted vanillate to catechol . Although carboxylated aromatic compounds which did not contain methoxyl groups were not by themselves growth supportive, protocatechuate and p-hydroxybenzoate (nonmethoxylated aromatic compounds) were converted to catechol and phenol, respectively, during carbon monoxide-dependent growth . Syringate is not subject to decarboxylation by C . thermoaceticum (Z . Wu, S . L . Daniel, and H . L . Drake, J . Bacteriol . 170:5705-5708, 1988), and sustained growth at the expense of syringate-derived methoxyl groups was dependent on supplemental CO2 . In contrast, vanillate was growth supportive in the absence of supplemental CO2, and 14CO2 was the major 14C-labeled product during {carboxyl-14C}vanillate-dependent growth . Furthermore, the decarboxylation of protocatechuate and p-hydroxybenzoate supported methanol- and 1,2,3-trimethoxybenzene-dependent growth (CO2 is required for growth at the expense of these substrates) when supplemental CO2 was depleted from the growth medium, and the decarboxylation of protocatechuate was concomitant with improved cell yields of methanol cultures . These findings demonstrate that (i) C . thermoaceticum is competent in the decarboxylation of certain aromatic compounds and (ii) under certain conditions, decarboxylation may be integrated to the flow of carbon and energy during acetogenesis. Microbiol Immunol, 1990, 34(12), 1041 - 7 The nucleotide and deduced amino acid sequences of EcoRI fragment containing the 5'-terminal region of Clostridium botulinum type E toxin gene cloned from Mashike, Iwanai and Otaru strains; Fujii N et al.; Chromosomal DNAs were extracted from toxigenic three Clostridium botulinum type E strains isolated from food-borne botulism . After digestion by EcoRI, the fragments were cloned into Escherichia coli by using bacteriophage lambda gt11 and screened with monoclonal antibody recognizing the light chain component of botulinum type E toxin . The fragments (about 1 kbp size) cloned from each strain were recloned into a plasmid vector pUC118 . The E . coli cells transformed with the recombinant plasmids produced 33 kDa protein with or without IPTG (isopropyl-beta-D-thiogalactopyranoside) which reacted with the monoclonal antibody . The nucleotide sequences of the cloned EcoRI fragments from the three type E strains were identical and contain the 5'-terminal region of the type E toxin gene . It was also found that there exist several highly homologous nucleotide sequences among the botulinum types A, C and E, and tetanus toxin genes in both translated and untranslated regions. Cytobios, 1990, 64(258-259), 181 - 96 Actin and lamin comprised filaments in the nuclei of Chinese hamster ovary cells affected with Clostridium difficile enterotoxin A; Kushnaryov VM et al.; The major change in the ultrastructure of Chinese hamster ovary (CHO) cells treated with Clostridium difficile enterotoxin A was the formation of bundles of filaments in the nucleoplasm . The filaments appeared after 2.5 h and disappeared by the fourth hour of incubation with the toxin . To partially characterize these filaments, laser diffractometry and ultrastructural immunocytochemistry were employed . The bundles consist of coiled filaments of about 11 nm and 16 nm diameter and a main long axial periodicity of about 26 nm . Postembedding immunogold labelling with monoclonal antibodies demonstrated that these intranuclear filaments are comprised mainly of actin, but also contain lamin and vinculin . Between 2.5 and 3 h of incubation with enterotoxin A, the lamins were located close to the nuclear envelope, but they were also consistently found scattered in the cytoplasm and nucleoplasm . Such an unusual distribution of lamins might mediate the adverse effects of enterotoxin A on nuclear organization and function and thus cause the eventual death of CHO cells. Toxicon, 1990, 28(11), 1368 - 71 Microinjection of alpha-toxin from Clostridium novyi type A promotes meiotic maturation in Xenopus laevis oocytes; Bette P et al.; Microinjection of purified alpha-toxin into Xenopus laevis oocytes induced meiotic maturation provided insulin was present in the medium . Induction of maturation as indicated by breakdown of the germinal vesicle depended on the amount of intracellular alpha-toxin (with a detection limit of 2 ng/oocyte) and on the concentration of insulin . The hormone concentrations used were inactive when given alone and so was alpha-toxin (1 micrograms/ml) applied from the outside . The results demonstrate an intracellular target for alpha-toxin whereas an extracellular target is apparently lacking in oocytes. Microbios, 1990, 64(260-261), 153 - 8 Isolation of Clostridium perfringens from foals; Kanoe M et al.; Clostridium perfingens was isolated from four of 29 healthy foals and from all twelve foals with gastrointestinal diseases . The range of viable counts of C . perfringens in the faeces was 10(1)-10(5)/g and in the intestinal specimens 10(1)-10(7)/g . Of 41 isolates of C . perfringens, 37 were considered to be type A . Enterotoxin of the organism was demonstrated in the intestinal contents of five of eight foals with enteric diseases . These findings suggested that C . perfringens is a likely pathogen of foal intestinal diseases. Med Microbiol Immunol (Berl), 1990, 179(5), 271 - 9 Cloning of Clostridium difficile toxin B gene and demonstration of high N-terminal homology between toxin A and B; von Eichel-Streiber C et al.; High titered Clostridium sordellii lethal toxin antiserum, cross-reactive with C . difficile cytotoxin B (ToxB), was used to isolate toxB fragments from a C . difficile expression library . Recombinant clones containing toxB fragments of the 5' and 3' end were isolate . A 2.5-kb HincII fragment of chromosomal DNA overlaps both groups of clones . A partial restriction map of the total toxB gene is presented . The gene is positioned upstream of utxA and toxA, toxB has a size of 6.9 kb, corresponding to a 250-kDa polypeptide . A partial sequence of the 5' end of toxB was determined . The sequence contains 398 bp upstream of toxB with a putative Shine-Dalgarno box (AGGAGA) and 609 bp of the toxB open reading frame . The N-terminal 203 amino acids of ToxB were compared with the N-terminal amino acids of the enterotoxin A (ToxA) . A homology of 64% of the residues was detected, which proves the relatedness of ToxA and ToxB of C . difficile. J Physiol (Paris), 1990, 84(4), 278 - 84 Molecular biology of Clostridial toxins: expression of mRNAs encoding tetanus and botulinum neurotoxins in Aplysia neurons; Mochida S et al.; mRNAs encoding the light chain of tetanus and botulinum neurotoxins were transcribed, in vitro, from the cloned and specifically truncated genes of Clostridium tetani and Clostridium botulinum, respectively, and injected into presynaptic identified cholinergic neurons of the buccal ganglia of Aplysia californica . The size of the current response measured in the voltage clamped postsynaptic neuron was taken as indicator of the quantity of acetylcholine released . Depression of neurotransmitter release similar to that observed when native light chains of the two toxins were injected but needing an additional delay of 30 to 40 minutes, demonstrated a successful expression of a foreign mRNA injected into a neuron in situ. J Physiol (Paris), 1990, 84(4), 262 - 6 Characterization of the ADP-ribosylation of actin by Clostridium botulinum C2 toxin and Clostridium perfringens iota toxin; Aktories K et al.; Clostridium botulinum C2 toxin and Clostridium perfringens iota toxin belong to a novel family of actin ADP-ribosylating toxins . ADP-ribosylation of actin inhibits actin polymerization and G-actin-associated ATPase activity . The ADP-form of actin is ADP-ribosylated at a higher rate than actin with bound ATP . ADP-ribosylation of actin is reversible, a reaction, which is accompanied by reconstitution of actin ATPase activity. Comp Immunol Microbiol Infect Dis, 1990, 13(4), 217 - 21 Apparition of Clostridium sp . and Bacteroides in the intestine of the newborn delivered by cesarian section; Bezirtzoglou E et al.; Anaerobic flora plays a key role in preventing intestinal colonization with potential pathogens . Nowadays, the mechanisms involved in the colonization resistance provided by the anaerobic microflora are to be clarified . Numerous factors seem to intervene in the regulation of the intestinal flora . The purpose of the present study was to correlate the presence or relative absence of Clostridium sp . and Bacteroides with the colonization by C . perfringens, which is involved in lethal infections in an immunologically compromised host . The intestinal bacterial colonization of 20 newborns delivered by cesarian section was assessed sequentially over the first 14 days of life . C . perifringens is a strongly reducing microorganism and undoubtedly causes a decrease in the oxidoreduction potential of the newborn feces favouring the subsequent colonization by other putrefactive bacteria . C . perfringens seems to be the precursor for installation of putrefractive bacteria, as Bacteroides and other Clostridium sp. Toxicon, 1990, 28(8), 963 - 73 ADP-ribosylation of cerebrocortical synaptosomal proteins by cholera, pertussis and botulinum toxins; Ashton AC et al.; Certain microbial toxins ADP-ribosylate G proteins that may be related to those postulated to participate in secretion, whilst botulinum neurotoxins, produced by Clostridium botulinum, block Ca2(+)-dependent neurotransmitter release . Thus, botulinum, pertussis and cholera toxins were examined for ADP-ribosyl transferase activity using isolated nerve terminals . Although type D botulinum, cholera and pertussis toxins exhibited such enzymic activity, this was not detectable with types A or B botulinum neurotoxins or their individual chains, in any synaptosomal fraction . Botulinum type D and pertussis toxins ADP-ribosylated proteins with mol . wt approximately 24,000 and 42,000 respectively, whereas cholera toxin modified several proteins including a 51,000/47,000 mol . wt doublet . Pre-incubation of synaptosomes with type A, B or D toxins did not inhibit type D-induced labelling in the corresponding lysate . Similar pre-incubations with cholera or pertussis toxins reduced ADP-ribosylation of their substrates . Hence, under conditions in which these botulinum toxins were shown to block Ca2(+)-dependent transmitter release no ADP-ribosylated substrate was produced in the intact nerve terminals . Moreover, direct correlation was not found between the concentration dependencies of type D toxin for protein modification and inhibition of {3H}noradrenaline release from synaptosomes . These collective findings implicate C3, a non-neurotoxic contaminant of type D, in the enzymic action . The substrate for type D toxin was found in the cytosolic fraction and to a lesser extent in synaptic membranes, the reverse of the situation for pertussis toxin . A combination of the membranes and cytosol was required for maximal labelling of the 51,000/47,000 doublet by cholera toxin . Purified synaptic vesicles contained proteins labelled by type D and pertussis toxins but lacked major cholera toxin substrates . Future research will determine the possible involvement of these toxin-susceptible vesicular proteins in transmitter release. C R Acad Sci III, 1990, 310(9), 383 - 7 {Clostridium bifermentans serovar malaysia, a new anaerobic bacterium pathogen to mosquito and blackfly larvae}; de Barjac H et al.; A strain of Clostridium bifermentans individualized as serovar malaysia (C.b.m.) according to its specific H antigen is toxic to mosquito and blackfly larvae when given orally . The toxicity occurs in sporulated cells which contain, in addition to spores, proteinic parasporal inclusion bodies and feather-like appendages; the amino acid content of the inclusion bodies is similar to that of Bacillus thuringiensis serovar israelensis (B.t.i.) and B . sphaericus crystals . The toxicity to Anopheles stephensi is as high as that of B.t.i . and the best strains of B . sphaericus . Culex pipiens is somewhat less susceptible, and Aedes aegypti much less . Pure parasporal inclusion bodies, isolated by ultracentrifugation on sucrose gradients, are highly toxic to mosquito larvae . The larvicidal power is destroyed by heating at 80 degrees C or by treatment with 50 mM NaOH . It is preserved by freeze-drying . The innocuity to mice of the sporulated cells is shown by different routes of administration: force-feeding, percutaneous, subcutaneous, intraperitoneal or intravenous injections . The potential for the biological control of mosquito and blackfly larvae is suggested. Acta Microbiol Pol, 1990, 39(1-2), 91 - 4 An extracellular material observed in Clostridium difficile strains; Sokol B et al.; Some extracellular material-- "capsule" has been observed among Clostridium difficile strains . C . difficile strains (44 examined) contain different proportions of cells with "capsule" and without "capsules" . Toxigenic strains contained fewer capsulated cells than non-toxigenic strains. Neuroscience, 1990, 37(3), 799 - 808 Terminal sprouting in mouse neuromuscular junctions poisoned with botulinum type A toxin: morphological and electrophysiological features; Angaut-Petit D et al.; Functional properties of terminal sprouts elicited by an in vivo injection of Clostridium botulinum type A toxin were studied in endplates of the Levator auris longus muscle of the mouse poisoned from a few days to 28 days beforehand . For this purpose, morphological observations of the extent of terminal sprouts and localization of acetylcholine receptors was performed in whole mount preparations . Sprouts appeared as thin unmyelinated filaments that run usually parallel to the longitudinal axis of the muscle fibres; labelling acetylcholine receptors revealed their line-shaped accumulation co-localized with the sprouts . In addition, presynaptic membrane currents elicited by nerve stimulation were recorded by external electrodes applied under visual control onto the membrane of pre-existing motor endings and newly formed sprouts . These recordings showed the presence of widespread triphasic waveforms which indicated active impulse propagation of the action potential over most of the length of the poisoned endings . Ca2+ influx and Ca2(+)-dependent K+ currents in the sprout membrane were found to be similar to those described in unpoisoned endings . The presence of normal Ca2+ influx, upon active depolarization, in the terminal sprout membranes together with the localization of acetylcholine receptors in front of these membranes, indicates that the terminal sprouts may play a role in the recovery of neuromuscular transmission after Clostridium botulinum poisoning. Int J Syst Bacteriol, 1990 Jan, 40(1), 40 - 4 Assignment of Clostridium bryantii to Syntrophospora bryantii gen . nov., comb . nov . on the basis of a 16S rRNA sequence analysis of its crotonate-grown pure culture; Zhao HX et al.; The Clostridium bryantii-Methanospirillum hungatei syntrophic coculture, grown on caproate, was adapted to grow on crotonate . Then, C . bryantii was isolated in pure culture from crotonate bottle plates . A 16S rRNA sequence analysis of the pure subculture revealed that, as a member of the gram-positive phylum, it was not closely related to any of the Clostridium species with which it was compared or to any of the other clusters in the gram-positive phylum with which it was compared . However, it was closely related to another syntrophic fatty acid-degrading bacterium, Syntrophomonas wolfei . On the basis of its phylogeny, physiology, and cell wall ultrastructure, we propose assignment of C . bryantii to Syntrophospora bryantii gen . nov., nov . comb. Rev Infect Dis, 1990 Jan-Feb, 12 Suppl 2, S192 - 9 Epidemiologic markers of Clostridium difficile; Tabaqchali S; A wide range of epidemiologic markers have been identified for Clostridium difficile . These markers are based on phenotypic characteristics of the organism, such as antibiotic resistance, bacteriocin or bacteriophage susceptibility, electrophoretic protein patterns, and immunologic markers . Methods for determining genetic markers include plasmid and DNA restriction endonuclease analysis and ribosomal RNA restriction patterns . These methods have been applied to various degrees in epidemiologic studies and have contributed to a better understanding of C . difficile-associated disease . The method based on the use of {35S}methionine-labeled proteins and the development of an automated scanner with computer analysis made possible the recognition of 15 distinct types of C . difficile, based on the major radiolabeled protein patterns . These proteins were strain-specific and immunogenic, as demonstrated by immunoblotting and DNA restriction endonuclease analysis . Epidemiologic studies revealed cross-infection among patients, nosocomial acquisition, and a direct relation between symptoms and type of C . difficile . The development of DNA probes based on antibiotic resistance genes, toxin A, and cloned specific common antigens is discussed. Acta Physiol Pol, 1990, 41(1-3), 79 - 86 Quantification of the potencies of EDRF-releasers from isolated rabbit aortic strips; Trybulec M et al.; We have compared several known releasers of endothelium-derived relaxing factor (EDRF)(13) in respect to their potencies to generate EDRF by endothelium of rabbit aortic strips (RbA) superfused with Krebs' buffer . The vasorelaxation by EDRF which is equivalent to 10 pmoles of GTN was evoked by 0.7 pmoles of substance P(SP), 50 pmoles of acetylcholine (Ach), 521 pmoles of calcium ionophore A 23187, 2720 pmoles of ADP . Threshold potencies of these agonists are inversely proportional to the maximum amount of EDRF released . Phospholipase C (PLC) from Clostridium perfringens at a dose of 0.1 U caused the relaxation of a similar magnitude . Phospholipase A2 (1 U), thrombin (1 U), bradykinin (30 nmoles) and serotonin (10 pmoles) did not release EDRF . It is concluded that endothelial cells of RbA differ from endothelial cells of other species in their susceptibility to release EDRF in response to various agonists. Am J Med, 1989 Dec 29, 87(6C), 10S - 13S In vitro antimicrobial activity and susceptibility testing of ofloxacin . Current status; Fuchs PC; The fluoroquinolone, ofloxacin, exhibits a broad antibacterial spectrum . Based on our data and a review of the literature, ofloxacin inhibited essentially 100 percent of staphylococci, including oxacillin-resistant strains, Haemophilus influenzae, Neisseria spp . and Branhamella catarrhalis . Ninety-five percent of Enterobacteriaceae were susceptible to ofloxacin . Pseudomonas aeruginosa and enterococci were less susceptible: 79 and 63 percent, respectively, were susceptible (minimal inhibitory concentration {MIC}, less than or equal to 2.0 micrograms/ml); 15 and 25 percent, respectively, were intermediate (MIC, 4 micrograms/ml); 3 and 6 percent, respectively, were resistant (MIC, more than or equal to 4 micrograms/ml) . Clostridium spp., including Clostridium difficile, were resistant to ofloxacin, but other anaerobic species, including the Bacteroides fragilis group (over 90 percent) were either susceptible or intermediate to ofloxacin . Ofloxacin is bactericidal; minimal bactericidal concentrations of ofloxacin rarely exceed the MICs by one doubling concentration . A modest inoculum effect has been observed with ofloxacin: MICs with inocula of 10(7) colony-forming units/ml are often two- to fourfold higher than those with inocula of 5 x 10(5) colony-forming units/ml . Susceptible organisms exposed serially to increasing concentrations of nalidixic acid developed increasing resistance to not only nalidixic acid, but also to all other quinolones, including ofloxacin . Correlations of disk diffusion inhibitory zone diameters using the 5-micrograms ofloxacin disk with ofloxacin MICs have been performed, and the disk diffusion zone diameter breakpoints recommended are: susceptible, greater than or equal to 16 mm; intermediate, 13 to 15 mm; resistant, less than or equal to 12 mm . Quality control parameters also are summarized. Biochem Biophys Res Commun, 1989 Dec 29, 165(3), 1364 - 70 Inhibition of Clostridium difficile toxin A and B by 1,2-cyclohexanedione modification of an arginine residue; Balfanz J et al.; Toxin A (enterotoxin) and toxin B (cytotoxin) of Clostridium difficile were both inactivated by the arginine specific reagent 1,2-cyclohexanedione . Molecular stability during the inactivation process was demonstrated by SDS-PAGE analysis showing the same migration rates for modified and unmodified forms of the 230 kDa toxin A and of the 250 kDa toxin B . Cytotoxicity of both