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survey of naturally and conventionally cured commercial frankfurters, ham, and bacon for physio-chemical characteristics that affect bacterial growth.natural and organic food regulations preclude the use of sodium nitrite/nitrate and other antimicrobials for processed meat products. consequently, processors have begun to use natural nitrate/nitrite sources, such as celery juice/powder, sea salt, and turbinado sugar, to manufacture natural and organic products with cured meat characteristics but without sodium nitrite. the objective of this study was to compare physio-chemical characteristics that affect clostridium perfringens and listeria mo ...201222857852
development of an antigen-capture enzyme-linked immunosorbent assay for clostridium perfringens beta2-toxin in porcine feces and the neonatal piglet intestine.an enzyme-linked immunosorbent assay (elisa) was developed for detection and quantitation of beta2-toxin in neonatal piglet intestinal contents. polystyrene plates were coated with polyclonal capture antibodies prepared against consensus recombinant beta2-toxin. the elisa was developed using consensus recombinant beta2-toxin, atypical recombinant beta2-toxin, purified consensus native beta2-toxin, and field samples of neonatal porcine intestinal contents. captured antigen was detected using a ho ...201222855377
enteritis associated with clostridium perfringens type a in 9-month-old calves.four 9-month-old simmental male calves were presented with a history of sudden death. the necropsy and microscopic findings allowed a diagnosis of enteritis and severe intraluminal hemorrhage with blood clots in the jejunum, suggestive of jejunal hemorrhage syndrome.201222851779
clostridium perfringens alpha-toxin recognizes the gm1a-trka complex.clostridium perfringens alpha-toxin is the major virulence factor in the pathogenesis of gas gangrene. alpha-toxin is a 43-kda protein with two structural domains; the n-domain contains the catalytic site and coordinates the divalent metal ions, and the c-domain is a membrane-binding site. the role of the exposed loop region (72-93 residues) in the n-domain, however, has been unclear. here we show that this loop contains a ganglioside binding motif (h … sxwy … g) that is the same motif seen in b ...201222847002
a middle-aged lady with a pyogenic liver abscess caused by clostridium perfringens.the pyogenic liver abscess caused by clostridium perfringens (c. perfringens) is a rare, but rapidly fatal infection. it is usually associated with malignancy and immunosuppression. we report the case of 50-year-old lady with the secondary liver metastases from rectal cancer presented with fever and epigastric pain. the identification of gram-positive bacilli septicaemia, the presence of gas-forming liver abscess and massive intravascular hemolysis should lead to the suspicion of c. perfringens ...201222993668
novel system for efficient isolation of clostridium double-crossover allelic exchange mutants enabling markerless chromosomal gene deletions and dna integration.isolation of clostridium mutants based on gene replacement via allelic exchange remains a major limitation for this important genus. use of a heterologous counterselection marker can facilitate the identification of the generally rare allelic exchange events. we report on the development of an inducible counterselection marker and describe its utility and broad potential in quickly and efficiently generating markerless dna deletions and integrations at any genomic locus without the need for auxo ...201222983967
identification of a lambda toxin-negative clostridium perfringens strain that processes and activates epsilon prototoxin intracellularly.clostridium perfringens type b and d strains produce epsilon toxin (etx), which is one of the most potent clostridial toxins and is involved in enteritis and enterotoxemias of domestic animals. etx is produced initially as an inactive prototoxin that is typically then secreted and processed by intestinal proteases or possibly, for some strains, lambda toxin. during the current work a unique c. perfringens strain was identified that intracellularly processes epsilon prototoxin to an active form c ...201222982043
ranking the disease burden of 14 pathogens in food sources in the united states using attribution data from outbreak investigations and expert elicitation.understanding the relative public health impact of major microbiological hazards across the food supply is critical for a risk-based national food safety system. this study was conducted to estimate the u.s. health burden of 14 major pathogens in 12 broad categories of food and to then rank the resulting 168 pathogen-food combinations. these pathogens examined were campylobacter, clostridium perfringens, escherichia coli o157:h7, listeria monocytogenes, norovirus, salmonella enterica, toxoplasma ...201222980012
[picture in clinical hematology; clostridium perfringens septicemia with intravascular hemolysis]. 201222970457
cysteine-scanning mutagenesis supports the importance of clostridium perfringens enterotoxin amino acids 80 to 106 for membrane insertion and pore formation.clostridium perfringens enterotoxin (cpe) causes the gastrointestinal symptoms of the second most common bacterial food-borne illness. previous studies suggested that a region named tm1, which has amphipathic characteristics and spans from amino acids 81 to 106 of the native cpe protein, forms a β-hairpin involved in β-barrel pore formation. to further explore the potential role of tm1 in pore formation, the single cys naturally present in cpe at residue 186 was first altered to alanine by mutag ...201222966051
the epidemiology of clostridium perfringens type a on ontario swine farms, with special reference to cpb2-positive isolates.there is poor understanding of most aspects of clostridium perfringens type a as a possible cause of neonatal diarrhea in piglets, and the prevalence and types of c. perfringens present on ontario swine farms is unknown. to study the prevalence of fecal c. perfringens and selected toxin genes, 48 ontario swine farms were visited between august 2010 and may 2011, and 354 fecal samples were collected from suckling pigs, lactating sows, weanling pigs, grower-finisher pigs, and gestating sows, as we ...201222947389
influence of beet sugar, calcium lactate, and staphylococcus xylosus (with nitrate reductase activity) on the chemical, microbiological, and sensorial properties of persian uncured frankfurters.this study investigated the effects of beet sugar (bs), calcium lactate (cl), and staphylococcus xylosus (sx) on the general characteristics of uncured frankfurters. minimum residual nitrite was observed in samples with a high level of bs and s. xylosus (8log(10) l0 viable cfu/g) after 2 mo. there was an increase in total aerobic counts in frankfurters after 4 wk. samples containing higher bs and cl had no clostridium perfringens at storage time. histamine content was similar for all treatments ...201222946602
generation and characterization of an inter-generic bivalent alpha domain fusion protein αcs from clostridium perfringens and staphylococcus aureus for concurrent diagnosis and therapeutic applications.to evaluate an inter-generic recombinant alpha domain fusion protein for simultaneous detection and neutralization of clostridium perfringens and staphylococcus aureus alpha toxins.201222563989
characterization of polymorphisms and isoforms of the clostridium perfringens phospholipase c gene (plc) reveals high genetic diversity.clostridium perfringens phospholipase c (cp-plc), also called alpha-toxin, is encoded by the plc gene and has been implicated in several diseases; however, only a few studies have described polymorphisms in this gene. the aim of this study was to analyze polymorphisms in the cp-plc nucleotide and amino acid sequences obtained from isolates from different regions and to compare them to clostridium phospholipase c sequences deposited in the ncbi database. environmental samples (sediment, poultry f ...201222560738
feeding jerusalem artichoke reduced skatole level and changed intestinal microbiota in the gut of entire male pigs.different levels of dried jerusalem artichoke were fed to entire male pigs 1 week before slaughter. the objective was to investigate the effect on skatole level in the hindgut and in adipose tissue, as well as the effect on microflora and short-chain fatty acids (scfa) in the hindgut. five experimental groups (n = 11) were given different dietary treatments 7 days before slaughtering: negative control (basal diet), positive control (basal diet + 9% chicory-inulin), basal diet + 4.1% jerusalem ar ...201222558928
clostridium perfringens infections initially attributed to norovirus, north carolina, 2010.we investigated an outbreak initially attributed to norovirus; however, clostridium perfringens toxicoinfection was subsequently confirmed. c. perfringens is an underrecognized but frequently observed cause of food-borne disease outbreaks. this investigation illustrates the importance of considering epidemiologic and laboratory data together when evaluating potential etiologic agents that might require unique control measures.201222550114
clostridium perfringens alpha-toxin and netb toxin antibodies and their possible role in protection against necrotic enteritis and gangrenous dermatitis in broiler chickens.necrotic enteritis (ne) and gangrenous dermatitis (gd) are important infectious diseases of poultry. although ne and gd share a common pathogen, clostridium perfringens, they differ in other important aspects such as clinical signs, pathologic symptoms, and age of onset. the primary virulence factors of c perfringens are its four major toxins (alpha, beta, epsilon, iota) and the newly described ne b-like (netb) toxin. while neutralizing antibodies against some c perfingens toxins are associated ...201222545552
epidermal growth factor modulates claudins and tight junctional functions in ovarian cancer cell lines.ovarian adenocarcinomas, like human ovarian surface epithelial cells, form functional tight junctions. tight junction molecules claudin-3 and claudin-4, which are the receptors of clostridium perfringens enterotoxin (cpe), are abnormally upregulated in epithelial ovarian cancers of all subtypes including, mucinous cystadenocarcinoma and serous cystadenocarcinoma. clostridium perfringens enterotoxin may be a novel tumor-targeted therapy for ovarian cancers. in epithelial ovarian cancers, overexpr ...201222544349
the majority of atypical cpb2 genes in clostridium perfringens isolates of different domestic animal origin are expressed.this study examined the prevalence and expression of the "consensus" and the "atypical"cpb2 genes in clostridium perfringens isolates from cattle, chickens, dogs, goats, horses, pigs and sheep using polymerase chain reaction (pcr), sodium dodecyl sulfate-polyacrylamide gel electrophoresis followed by western blotting. almost all porcine isolates (12/14) carried and expressed the consensus form of cpb2 but, when present in 108 non-porcine isolates, the gene was usually the atypical form (40 atypi ...201222542269
bacterial contamination of tile drainage water and shallow groundwater under different application methods of liquid swine manure.a 2 year field experiment evaluated liquid manure application methods on the movement of manure-borne pathogens (salmonella sp.) and indicator bacteria (escherichia coli and clostridium perfringens) to subsurface water. a combination of application methods including surface application, pre-application tillage, and post-application incorporation were applied in a randomized complete block design on an instrumented field site in spring 2007 and 2008. tile and shallow groundwater were sampled imme ...201222540289
reduction of bilirubin ditaurate by the intestinal bacterium clostridium perfringens.bilirubin is degraded in the human gut by microflora into urobilinoids. in our study we investigated whether the bilirubin-reducing strain of clostridium perfringens can reduce bilirubin ditaurate (bdt), a bile pigment of some lower vertebrates, without hydrolysis of the taurine moiety. c. perfringes was incubated under anaerobic conditions with bdt; reduction products were quantified by spectrophotometry and separated by tlc. based on rf values of bdt reduction products and synthetic urobilinog ...201222540115
observing the confinement potential of bacterial pore-forming toxin receptors inside rafts with nonblinking eu(3+)-doped oxide nanoparticles.we track single toxin receptors on the apical cell membrane of mdck cells with eu-doped oxide nanoparticles coupled to two toxins of the pore-forming toxin family: α-toxin of clostridium septicum and ε-toxin of clostridium perfringens. these nonblinking and photostable labels do not perturb the motion of the toxin receptors and yield long uninterrupted trajectories with mean localization precision of 30 nm for acquisition times of 51.3 ms. we were thus able to study the toxin-cell interaction at ...201222677383
identification and proteome analysis of the two-component virr/virs system in epidemic streptococcus suis serotype 2.streptococcus suis serotype 2 (ss2) is an important zoonotic pathogen that infects pigs and sporadically causes serious infections in humans. two recent large-scale outbreaks of human streptococcal toxic-shock-like syndrome with high mortality occurred in china, posing new challenges for global public health. however, the global regulation of the virulence of epidemic ss2 isolates lacks a systematic understanding. in this study, we performed a mutational and functional analysis of an ss2 two-com ...201222670712
salvage liver transplantation for hepatic gas gangrene.hepatic gas gangrene is an uncommon situation mainly due to bacterial infection by clostridium perfringens. it remains a life-threatening condition associated with a high mortality rate. quick diagnosis and aggressive therapy including liver transplantation should be proposed to improve the outcome. this report describes a rare case of hepatic gas gangrene on native liver, secondary to iatrogenic hepatic artery thrombosis and instrumental biliary tree infection, which was successfully treated by ...201222669442
molecular characteristics of clostridium perfringens tpel toxin and consequences of mono-o-glcnacylation of ras in living cells.tpel is a member of the family of clostridial glucosylating toxins produced by clostridium perfringens type a, b, and c strains. in contrast to other members of this toxin family, it lacks a c-terminal polypeptide repeat domain, which is suggested to be involved in target cell binding. it was shown that the glucosyltransferase domain of tpel modifies ras in vitro by mono-o-glucosylation or mono-o-glcnacylation (nagahama, m., ohkubo, a., oda, m., kobayashi, k., amimoto, k., miyamoto, k., and saku ...201222665487
comparison of mucosal absorption-enhancing activity between a claudin-3/-4 binder and a broadly specific claudin binder.intercellular spaces between adjacent mucosal epithelial cells are sealed by tight junctions (tjs) that prevent the free movement of solutes across the epithelium. claudins (cls), a family of 27 integral membrane proteins, are essential components for tj seals. we previously used a cl-3/-4 binder, the c-terminal fragment of clostridium perfringens enterotoxin (c-cpe), to show that cl modulation is a promising method to enhance mucosal absorption. recently, by using a c-cpe mutant library, we dev ...201222659740
antimicrobial susceptibility of canine clostridium perfringens strains from switzerland.fifty clostridium perfringens strains were isolated from individual dogs with acute diarrhoea that were not given antibiotics. toxin types and minimal inhibitory concentrations of 15 antibiotics were determined for each of them. all strains harboured the alpha-toxin gene, 12 of them had both the alpha- and entero-toxin gene and 5 had both the alpha- and beta2-toxin gene. eighteen percent of the isolates showed resistance to tetracycline and 54 % showed decreased susceptibility to metronidazole w ...201222653699
the effect of genetically modified lactobacillus plantarum 590 on the gut health of sprague-dawley rats.lp was a generally recognized as safe microorganism. lactobacillus plantarum 590 was obtained by inserting nisi gene into lp genome to help it tolerate higher concentration nisin. as the unintended effects of the genetically modified microorganism (gmm) are the most important barriers to the progress of gmm, we have performed a useful exploration to establish a new in vivo evaluation model for gmm from the point of view of intestinal health. in this study, sprague-dawley rats were orally adminis ...201222648689
fulminant clostridium perfringens sepsis during induction chemotherapy in childhood leukemia. 201222631574
fluorescent probe for detection of bacteria: conformational trigger upon bacterial reduction of an azo bridge.using biomimetic chemical reduction or clostridium perfringens cell extract containing azoreductase, the dimer-fluorescent probe 2,4-o-bisdansyl-6,7-diazabicyclooct-6-ene, which possesses a conformationally constrained cis-azo bridge, is reduced to the tetra-equatorial 2,4-o-bisdansyl-cyclohexyl-3,5-bisammonium salt which exhibits fluorescence indicative of a dansyl monomer.201222618019
quantitative analyses of genes associated with mucin synthesis of broiler chickens with induced necrotic enteritis.clostridial infection of the intestine can result in necrotic enteritis (ne), compromising production and health of poultry. mucins play a major role in protecting the intestinal epithelium from infection. the relative roles of different mucins in gut pathology following bacterial challenge are unclear. this study was designed to quantify the expression of mucin and mucin-related genes, using intestinal samples from an ne challenge trial where birds were fed diets with or without in-feed antimic ...201222582290
development of real-time pcr for the detection of clostridium perfringens in meats and vegetables.a real-time pcr assay was developed and validated inhouse specifically for the detection of clostridium perfringens (cl. perfringens) in meats and vegetables by comparing with the culture method. the detection limit of the real-time pcr assay in phosphate-buffered saline was 10² cfu/ml. when the two methods were compared in food samples inoculated with cl. perfringens, the culture method detected 52 positives, whereas real-time pcr detected 51 positives out of 160 samples. the difference was wit ...201222534301
nitrergic response to clostridium perfringens infection in the rat brain regions: effect of red light irradiation.a single intraperitoneal injection of a gram-positive pathogen clostridium perfringens (cp) causes a remarkable down-regulation the constitutive nitric oxide synthase (cnos) with a simultaneous increase in the activity of inducible nos (inos) and the level of reactive nitrogen species in the rat brain major regions (cortex, striatum, hippocampus and hypothalamus) at 48 h post-administration of cp. treatment by both a semiconductor laser (scl) and/or a light-emitting diode (led) with same wavelen ...201222533509
freezing or adding trypsin inhibitor to equine intestinal contents extends the lifespan of clostridium perfringens beta toxin for diagnostic purposes.clostridium perfringens type c causes necrotizing enteritis mostly in neonatal animals of several species, including horses. the virulence of c. perfringens type c is mostly mediated by beta toxin (cpb). this toxin is highly sensitive to the action of trypsin and other proteases, which explains the increased susceptibility of neonatal animals to type c infections. final confirmation of type c disease diagnosis should be based on detection of cpb in the intestinal content of affected animals. how ...201222516562
survival trends of staphylococcus aureus, pseudomonas aeruginosa, and clostridium perfringens in a sandy south florida beach.the search for alternative indicators of disease-risk from non-enteric pathogens at the beach revealed high densities of targeted bacteria. to explain the high numbers of potential non-enteric pathogens, staphylococcus aureus and pseudomonas aeruginosa, in beach sand, we investigated factors affecting their survival and distribution, as well as those of a potential fecal indicator, clostridium perfringens. results indicated greater s. aureus and p. aeruginosa survival and proliferation in steril ...201222516512
genetic relatedness and netb prevalence among environmental clostridium perfringens strains associated with a broiler flock affected by mild necrotic enteritis.in a previous study we investigated pulsed-field gel electrophoresis (pfge) genotype diversity and prevalence of the netb toxin gene in clostridium perfringens (cp) isolates recovered from a broiler flock (flock 1) affected by necrotic enteritis (ne). in this follow-up work, we examined samples collected before placement of flock 1, to see if ne during rearing could be traced back to the cleaned and empty building or the day-old chicks. litter from the next flock in the same building (flock 2) w ...201222516191
non-soluble fibres and narasin reduce spontaneous gizzard erosion and ulceration in broiler chickens.the prevalence and severity of gizzard erosion and ulceration syndrome (geu) in broilers is affected by a number of predisposing and preventive factors. two broiler experiments with almost identical basal diets were conducted to investigate the effect of dietary oat hulls, access to litter and the antimicrobial compound narasin on geu. the effects on particle size of duodenal digesta, ileal starch concentration, caecal clostridium perfringens counts, necrotic enteritis and production performance ...201222515541
enterotoxigenic clostridium perfringens: detection and identification.recent advances in understanding the genetics of enterotoxigenic clostridium perfringens, including whole genome sequencing of a chromosomal cpe strain and sequencing of several cpe-carrying large plasmids, have led to the development of molecular approaches to more precisely investigate isolates involved in human gastrointestinal diseases and isolates present in the environment. sequence-based pcr genotyping of the cpe locus (cpe genotyping pcr assays) has provided new information about cpe-pos ...201222504431
innate immune response to yeast-derived carbohydrates in broiler chickens fed organic diets and challenged with clostridium perfringens.necrotic enteritis (ne) caused by clostridium perfringens is a reemerging disease of economic importance in areas of the world where antibiotic growth promoters have been banned. the effect of mannan-oligosaccharide (mos) supplementation in organic diets of broilers challenged with c. perfringens on performance, gut morphology, and innate immunity was investigated. three hundred ross-308 broilers were fed antibiotic-free certified organic starter and grower diets. on d 14, birds were orally chal ...201222499867
differential gene expression profiles of β-defensins in the crop, intestine, and spleen using a necrotic enteritis model in 2 commercial broiler chicken lines.changes in the expression levels of avian β-defensin (avbd) mrna were evaluated in necrotic enteritis (ne) disease model in 2 genetically disparate commercial broiler chicken lines: ross and cobb. the ne was initiated in the gut by a previously established co-infection model using oral eimeria maxima infection followed by a clostridium perfringens challenge. among the 14 avbd types examined, there was a tissue-specific expression of avbd transcripts: avbd1, avbd7, and avbd9 in the crop; avbd8, a ...201222499864
survival and germination of clostridium perfringens spores during heating and cooling of ground pork.the effect of heating rate on the heat resistance, germination, and outgrowth of clostridium perfringens spores during cooking of cured ground pork was investigated. inoculated cured ground pork portions were heated from 20 to 75°c at a rate of 4, 8, or 12°c/h and then held at 75°c for 48 h. no significant differences (p > 0.05) in the heat resistance of c. perfringens spores were observed in cured ground pork heated at 4, 8, or 12°c/h. at heating rates of 8 and 12°c/h, no significant difference ...201222488055
changes in the caecal microflora of chickens following clostridium perfringens challenge to induce necrotic enteritis.necrotic enteritis is a disease of considerable economic importance to the global poultry industry. clostridium perfringens has long been recognised as the etiological agent of the disease. however, disease initiation and progression is complex and appears to be precipitated by a range of predisposing factors. the present study investigated microbial interactions in the caecum of birds challenged with c. perfringens that developed necrotic enteritis. bacterial populations of healthy and diseased ...201222487456
co-infection with toxoplasma gondii and clostridium perfringens in a postpartum woman with uterine gas gangrene: a case report.toxoplasmosis is a protozoan infection caused by toxoplasma gondii. we report a case of toxoplasma gondii and clostridium perfringens co-infection complicating uterine gas gangrene following a term pregnancy. the histological examination of the necrotic uterine tissues and uterine swab cultures obtained at laparotomy revealed t. gondii and c. perfringens, respectively. treatment was administered with bactericidal activity against both pathogens and the patient had an uneventful post-operative re ...201222487420
modifications in perfringolysin o domain 4 alter the cholesterol concentration threshold required for binding.changes in the cholesterol content of cell membranes affect many physiological and pathological events, including the formation of arterial plaques, the entry of virus into cells, and receptor organization. measuring the trafficking and distribution of cholesterol is essential to understanding how cells regulate sterol levels in membranes. perfringolysin o (pfo) is a cytolysin secreted by clostridium perfringens that requires cholesterol in the target membrane for binding. the specificity of pfo ...201222482748
carbohydrate recognition by an architecturally complex α-n-acetylglucosaminidase from clostridium perfringens.cpgh89 is a large multimodular enzyme produced by the human and animal pathogen clostridium perfringens. the catalytic activity of this exo-α-d-n-acetylglucosaminidase is directed towards a rare carbohydrate motif, n-acetyl-β-d-glucosamine-α-1,4-d-galactose, which is displayed on the class iii mucins deep within the gastric mucosa. in addition to the family 89 glycoside hydrolase catalytic module this enzyme has six modules that share sequence similarity to the family 32 carbohydrate-binding mod ...201222479408
oxygen measurements in platelet fluids - a new non-invasive method to detect bacterial contaminations in platelets.the residual risk for bacterial contamination in blood components especially in platelets is one to two orders of magnitude higher than for transfusion relevant viral infections. the majority of all bacterial transmitted fatalities occurred at the end of platelet shelf life. therefore, the maximum shelf life of platelet concentrates (pc) was reduced to 4 days after blood donation in germany in 2008.201222462725
effects of dietary additives and early feeding on performance, gut development and immune status of broiler chickens challenged with clostridium perfringens.the effects of dietary additives and holding time on resistance and resilience of broiler chickens to clostridium perfringens challenge were investigated by offering four dietary treatments. these were a negative control (basal), a positive control (zn-bacitracin) and two dietary additives, mannanoligosaccharides (mos), and acidifier. two holding times included (a) immediate access to feed and water post hatch (fed) and (b) access to both feed and water 48 h post hatch (held). chicks fed zn-baci ...201225049595
genome sequencing and analysis of a type a clostridium perfringens isolate from a case of bovine clostridial abomasitis.clostridium perfringens is a common inhabitant of the avian and mammalian gastrointestinal tracts and can behave commensally or pathogenically. some enteric diseases caused by type a c. perfringens, including bovine clostridial abomasitis, remain poorly understood. to investigate the potential basis of virulence in strains causing this disease, we sequenced the genome of a type a c. perfringens isolate (strain f262) from a case of bovine clostridial abomasitis. the ∼3.34 mbp chromosome of c. per ...201222412860
terminal sialic acids are an important determinant of pulmonary endothelial barrier integrity.the surface of vascular endothelium bears a glycocalyx comprised, in part, of a complex mixture of oligosaccharide chains attached to cell-surface proteins and membrane lipids. importantly, understanding of the structure and function of the endothelial glycocalyx is poorly understood. preliminary studies have demonstrated structural differences in the glycocalyx of pulmonary artery endothelial cells compared with pulmonary microvascular endothelial cells. herein we begin to probe in more detail ...201222387293
novel transmembrane receptor involved in phagosome transport of lysozymes and β-hexosaminidase in the enteric protozoan entamoeba histolytica.lysozymes and hexosaminidases are ubiquitous hydrolases in bacteria and eukaryotes. in phagocytic lower eukaryotes and professional phagocytes from higher eukaryotes, they are involved in the degradation of ingested bacteria in phagosomes. in entamoeba histolytica, which is the intestinal protozoan parasite that causes amoebiasis, phagocytosis plays a pivotal role in the nutrient acquisition and the evasion from the host defense systems. while the content of phagosomes and biochemical and physio ...201222383874
development and application of a polymicrobial, in vitro, wound biofilm model.the goal of this investigation was to develop an in vitro, polymicrobial, wound biofilm capable of supporting the growth of bacteria with variable oxygen requirements.201222353049
fast kinetics of nucleotide binding to clostridium perfringens family ii pyrophosphatase containing cbs and drtgg domains.we earlier described cbs-pyrophosphatase of moorella thermoacetica (mtcbs-ppase) as a novel phosphohydrolase that acquired a pair of nucleotide-binding cbs domains during evolution, thus endowing the protein with the capacity to be allosterically regulated by adenine nucleotides (jämsen, j., tuominen, h., salminen, a., belogurov, g. a., magretova, n. n., baykov, a. a., and lahti, r. (2007) biochem. j., 408, 327-333). we herein describe a more evolved type of cbs-pyrophosphatase from clostridium ...201222348476
determining potential indicators of cryptosporidium oocysts throughout the wastewater treatment process.most research on wastewater treatment efficiency compliance focuses on physicochemical and microbial indicators; however, very little emphasis has been placed so far on determining suitable indicator organisms to predict the discharge level of pathogens from treatment plants. in this study, raw wastewater, activated sludge, and the resulting final effluents and biosolids in four municipal wastewater treatment plants (wwtps a, b, c and d) were seasonally investigated for human-virulent water-born ...201222339022
threonine requirement of broiler chickens during subclinical intestinal clostridium infection.the aim of this study was to determine the threonine requirement of broilers during a subclinical clostridium infection. three experiments were performed: experiments 1 and 2 to investigate the dose-response of threonine supplementation during infection and experiment 3 to validate the threonine requirement during infection. in each experiment, 1-d-old ross 308 male broilers were used. an infection model was used with inoculation of eimeria maxima and clostridium perfringens at d 9 and 14 of age ...201222334739
immunological responses to clostridium perfringens alpha-toxin in two genetically divergent lines of chickens as influenced by major histocompatibility complex genotype.chickens genetically selected for low (la) or high (ha) antibody response to srbc displayed a correlated change in mhc, so that la chickens were 96% b13 and ha chickens were 96% b21. the la line appears to be less susceptible to invasion by extracellular pathogens, whereas ha chickens are more resistant to infection by intracellular organisms. resistance to clostridium perfringens is one instance in which the lines do not follow their established trend of pathogen susceptibility, where during a ...201222334734
clostridium perfringens detected by peripheral blood smear. 201222333387
creation and biochemical analysis of a broad-specific claudin binder.claudins (cl) are a family of tetra-transmembrane proteins that are the structural and functional components of tight junctions (tj). cls are promising targets for drug development because of their role in mucosal drug absorption and cancer. however, cl-targeted drug development has been delayed because cls have low antigenicity and preparing cl proteins is difficult. we developed a cl binder by using the c-terminal fragment of clostridium perfringens enterotoxin (c-cpe) and a baculoviral displa ...201222317861
treatment of severe hemolytic anemia caused by clostridium perfringens sepsis in a liver transplant recipient.clostridium perfringens bacteremia accompanied by extensive intravascular hemolysis is an almost inescapably fatal infection.201222316146
sequence of two plasmids from clostridium perfringens chicken necrotic enteritis isolates and comparison with c. perfringens conjugative plasmids.twenty-six isolates of clostridium perfringens of different mlst types from chickens with necrotic enteritis (ne) (15 netb-positive) or from healthy chickens (6 netb-positive, 5 netb-negative) were found to contain 1-4 large plasmids, with most netb-positive isolates containing 3 large and variably sized plasmids which were more numerous and larger than plasmids in netb-negative isolates. netb and cpb2 were found on different plasmids consistent with previous studies. the pathogenicity locus nel ...201223189158
production and characterization of clostridium perfringens recombinant β toxoid.in this work, we produced and evaluated a vaccine based on a β toxoid of clostridium perfringens type c produced in escherichia coli (rbt). the non-toxic rbt was innocuous for mice and induced 14 iu ml(-1) of β antitoxin in rabbits, complying with the european pharmacopeia and cfr9 - usda guidelines.201222306065
study of the cultivable microflora of the large intestine of the rat under varied environmental hyperbaric pressures.we conducted an in vivo experiment to investigate the effect of hyperbarometric air pressure on the quantity and composition of the cultivable microflora of the large intestine.201222305555
the effect of clostridium perfringens type c strain cn3685 and its isogenic beta toxin null mutant in goats.clostridium perfringens type c is an important cause of enteritis and/or enterocolitis in several animal species, including pigs, sheep, goats, horses and humans. the disease is a classic enterotoxemia and the enteric lesions and associated systemic effects are thought to be caused primarily by beta toxin (cpb), one of two typing toxins produced by c. perfringens type c. this has been demonstrated recently by fulfilling molecular koch's postulates in rabbits and mice. we present here an experime ...201222296994
identification and in vitro analysis of the gatd/murt enzyme-complex catalyzing lipid ii amidation in staphylococcus aureus.the peptidoglycan of staphylococcus aureus is characterized by a high degree of crosslinking and almost completely lacks free carboxyl groups, due to amidation of the d-glutamic acid in the stem peptide. amidation of peptidoglycan has been proposed to play a decisive role in polymerization of cell wall building blocks, correlating with the crosslinking of neighboring peptidoglycan stem peptides. mutants with a reduced degree of amidation are less viable and show increased susceptibility to methi ...201222291598
claudin-4 as therapeutic target in cancer.intercellular junctional complexes such as adherens junctions and tight junctions are critical regulators of cellular polarity, paracellular permeability and metabolic and structural integrity of cellular networks. abundant expression analysis data have yielded insights into the complex pattern of differentially expressed cell-adhesion proteins in epithelial cancers and provide a useful platform for functional, preclinical and clinical evaluation of novel targets.201222286027
effect of sewage treatment plants and diffuse pollution on the occurrence of protozoal parasites in the course of a small river.in germany, protozoal parasites are detected frequently in surface waters. this study aims to assess the parasitological pollution in a river course and two of its tributaries under regular weather conditions. cryptosporidium was detected in 67% of all samples. the median concentration was 4 oocysts/100l. giardia lamblia were detected in 90% of the samples. the median concentration of g. lamblia was 22 cysts/100l and increased significantly following the river course. a statistically significant ...201222285254
the peptidoglycan hydrolase tcpg is required for efficient conjugative transfer of pcw3 in clostridium perfringens.peptidoglycan hydrolases that are specifically associated with bacterial conjugation systems are postulated to facilitate the assembly of the transfer apparatus by creating a temporally and spatially controlled local opening in the peptidoglycan layer. to date little is known about the role of such enzymes in conjugation systems from gram-positive bacteria. conjugative plasmids from the gram-positive pathogen clostridium perfringens all encode two putative peptidoglycan hydrolases, tcpg and tcpi ...201222244927
complete genome sequence of the podoviral bacteriophage φcp24r, which is virulent for clostridium perfringens.bacteriophage φcp24r was isolated from raw sewage from a waste treatment plant, and lytic activity was observed against a type a clostridium perfringens isolate. electron microscopy revealed a small virion (44-nm-diameter icosahedral capsid) with a short, non-contractile tail, indicative of a member of the family podoviridae. the phage had a linear, double-stranded dna genome of 18,919 base pairs (bp) with 41 bp inverted terminal repeats and a type b dna polymerase, which are characteristics of ...201222218967
clostridium perfringens sepsis and liver abscess following laparoscopic cholecystectomy.clostridium perfringens sepsis with intravascular haemolysis is a catastrophic process with a reported mortality of between 90 to 100%. we successfully treated a case of severe clostridial infection with a liver abscess following laparoscopic cholecystectomy, the first to our knowledge. a 59-year-old man presented one week after an uneventful laparoscopic cholecystectomy with jaundice, peritonism, sepsis and acute renal failure. he was found to have a haemolytic anaemia, unconjugated hyperbiliru ...201224960720
claudin-6: a novel receptor for cpe-mediated cytotoxicity in ovarian cancer.claudins are integral tight junction proteins that are responsible for maintaining the integrity of epithelial cell architecture and cell polarity. claudin-3 and -4 are overexpressed in several cancers and have been shown to act as receptors for the clostridium perfringens enterotoxin (cpe), a toxin that causes rapid cell lysis. cpe has demonstrated effectiveness in treating several different cancers in mouse models, provided that these cancers express claudin-3 or claudin-4. here, we show that ...201223552466
myonecrosis by clostridium septicum in a dog, diagnosed by a new multiplex-pcr.clostridial myositis is an acute, generally fatal toxemia that is considered to be rare in pet animals. the present report describes an unusual canine clostridial myositis that was diagnosed by a new multiplex-pcr (mpcr) designed for simultaneous identification of clostridium sordellii, clostridium septicum, clostridium perfringens type a, clostridium chauvoei, and clostridium novyi type a. a ten-month-old male rottweiler dog, that had displayed lameness and swelling of the left limb for 12 h, w ...201222975141
cd44 promotes intoxication by the clostridial iota-family toxins.various pathogenic clostridia produce binary protein toxins associated with enteric diseases of humans and animals. separate binding/translocation (b) components bind to a protein receptor on the cell surface, assemble with enzymatic (a) component(s), and mediate endocytosis of the toxin complex. ultimately there is translocation of a component(s) from acidified endosomes into the cytosol, leading to destruction of the actin cytoskeleton. our results revealed that cd44, a multifunctional surface ...201223236484
nosocomial infections in leukemic and solid-tumor cancer patients: distribution, outcome and microbial spectrum of anaerobes.nosocomial infections cause significant morbidity and mortality in cancer patients. as a result of their debilitated immune system, cancer patients are likely candidates for colonization with anaerobes. we sought to compare the distribution of nosocomial infections in neutropenic and non-neutropenic cancer patients and to calculate the associated mortality rates.201223231490
sensitivity of pathogenic and commensal bacteria from the human colon to essential oils.the microbiota of the intestinal tract plays an important role in colonic health, mediating many effects of dietary components on colonic health and during enteric infections. in the context of the increasing incidence of antibiotic resistance in gut bacteria, complementary therapies are required for the prevention and treatment of enteric infections. here we report the potential application of essential oils (eo) and pure eo compounds to improve human gut health. nerolidol, thymol, eugenol and ...201222878397
presence and molecular characterization of clostridium difficile and clostridium perfringens in intestinal compartments of healthy horses.clostridium difficile and clostridium perfringens are commonly associated with colitis in equids, but healthy carriers exist. scarce information is available on the prevalence of clostridium spp. in gastrointestinal compartments other than faeces in healthy horses, and it is unknown whether faecal samples are representative of proximal compartments. the objectives were to investigate the prevalence of c. difficile and c. perfringens in different intestinal compartments of healthy adult horses an ...201222748233
prophage carriage and diversity within clinically relevant strains of clostridium difficile.prophages are encoded in most genomes of sequenced clostridium difficile strains. they are key components of the mobile genetic elements and, as such, are likely to influence the biology of their host strains. the majority of these phages are not amenable to propagation, and therefore the development of a molecular marker is a useful tool with which to establish the extent and diversity of c. difficile prophage carriage within clinical strains. to design markers, several candidate genes were ana ...201222706062
adherence of clostridium difficile spores to caco-2 cells in culture.clostridium difficile is the causative agent of the majority of antibiotic associated diarrhoea cases. c. difficile spores are recognized as the persistent and infectious morphotype as well as the vehicle of transmission of cdi. however, there is a lack of knowledge on how c. difficile spores interact with the host's epithelial surfaces. in this context, we have characterized the ability of c. difficile spores to adhere to human caco-2 cells. despite the similarities in spore-surface hydrophobic ...201222595914
treatment with histamine-type 2 receptor antagonists and omeprazole increase the risk of diarrhoea in neonatal foals treated in intensive care units.the use of anti-ulcer medication in the neonatal intensive care unit (icu) is common due to the concern for development of catastrophic gastric ulcerdisease. in man, however, the use of acid-suppressive medication has been shown in some studies to be a substantial riskfactorfor the development of clostridium difficile-associated diarrhoea (cdad), bacteraemia and neonatal sepsis.201222594032
longitudinal study of clostridium difficile and antimicrobial susceptibility of escherichia coli in healthy horses in a community setting.point prevalence studies have reported carriage rates of enteric pathogens in healthy horses, but longitudinal data are lacking. commensal e. coli is an indicator organism to evaluate antimicrobial resistance of enteric bacteria, yet there are limited data for horses. the objectives of this study were to investigate and molecularly characterize isolates of clostridium difficile, clostridium perfringens and salmonella, collected sequentially over a one year period, and to determine the antibiotic ...201222554764
bidirectional attack on the actin cytoskeleton. bacterial protein toxins causing polymerization or depolymerization of actin.the actin cytoskeleton is one of the major targets of bacterial protein toxins. the family of binary actin-adp-ribosylating toxins, including clostridium difficile transferase cdt, clostridium perfringens iota toxin and clostridium botulinum c2 toxin, modifies arginine-177 of actin. thereby actin polymerization is blocked. by contrast, actin polymerization is facilitated by the tripartite photorhabdus luminescens toxin complex including tccc3, which modifies actin at threonine-148. the review di ...201222543189
fk506-binding protein 51 interacts with clostridium botulinum c2 toxin and fk506 inhibits membrane translocation of the toxin in mammalian cells.the binary clostridium botulinum c2 toxin consists of the binding/translocation component c2iia and the separate enzyme component c2i. c2iia delivers c2i into the cytosol of eukaryotic target cells where c2i adp-ribosylates actin. after receptor-mediated endocytosis of the c2iia/c2i complex, c2iia forms pores in membranes of acidified early endosomes and unfolded c2i translocates through the pores into the cytosol. membrane translocation of c2i is facilitated by the activities of host cell chape ...201222420783
comparative in vitro activities of lff571 against clostridium difficile and 630 other intestinal strains of aerobic and anaerobic bacteria.the in vitro activities of lff571, a novel analog of ge2270a that inhibits bacterial growth by binding with high affinity for protein synthesis elongation factor tu, fidaxomicin, and 10 other antimicrobial agents were determined against 50 strains of clostridium difficile and 630 other anaerobic and aerobic organisms of intestinal origin. lff571 possesses potent activity against c. difficile and most other gram-positive anaerobes (mic(90), ≤ 0.25 μg/ml), with the exception of bifidobacteria and ...201222290948
garlic derivative propyl propane thiosulfonate is effective against broiler enteropathogens in vivo.two experiments were carried out to study the effects of dietary supplementation with the garlic (allium sativum)-derived product propyl propane thiosulfonate (pts-o) on the intestinal log(10) number of copies of enteropathogens in broiler chickens, together with their intestinal morphology and growth performance. the additive had no significant effect on feed intake at any dose assayed. in experiment 1 (1 to 21 d of age), the bw of chickens fed on 45 mg of pts-o/kg of diet was higher (p < 0.01) ...201222912448
enteropathogens identified in dogs entering a florida animal shelter with normal feces or diarrhea.to determine the frequency of enteropathogens in dogs entering an animal shelter with normal feces or diarrhea.201222812470
lyophilized carnobacterium divergens as7 bacteriocin preparation improves performance of broiler chickens challenged with clostridium perfringens.the present study aimed to investigate the effects of carnobacterium divergens as7 bacteriocin (divercin as7) on growth performance, digestibility, fermentation processes, selected microbial populations, and histomorphology in broiler chickens challenged with a mixture of 3 clostridium perfringens isolates. in total, 480 one-day-old male ross 308 chicks were randomly assigned to 4 experimental groups (12 replicate pens of 10 birds per treatment). the diets were either nonsupplemented or suppleme ...201222802184
the effect of selected synbiotics on microbial composition and short-chain fatty acid production in a model system of the human colon.prebiotics, probiotics and synbiotics can be used to modulate both the composition and activity of the gut microbiota and thereby potentially affecting host health beneficially. the aim of this study was to investigate the effects of eight synbiotic combinations on the composition and activity of human fecal microbiota using a four-stage semicontinuous model system of the human colon.201223082149
evaluation of impact of exposure of sudan azo dyes and their metabolites on human intestinal bacteria.sudan azo dyes are banned for food usage in most countries, but they are illegally used to maintain or enhance the color of food products due to low cost, bright staining, and wide availability of the dyes. in this report, we examined the toxic effects of these azo dyes and their potential reduction metabolites on 11 prevalent human intestinal bacterial strains. among the tested bacteria, cell growth of 2, 3, 5, 5, and 1 strains was inhibited by sudan i, ii, iii, iv, and para red, respectively. ...201222634331
distinct gut microbiota in southeastern african and northern european infants.the intestinal microbiota composition in infants reflects the early environment. our objective was to compare the gut microbiota in 6-month-old infants living in rural malawi with children of the same age living in urban finland, both being breast-fed and having an age-appropriate diet typical for each area.201222228076
treatment of bran containing bread by baking enzymes; effect on the growth of probiotic bacteria on soluble dietary fiber extract in vitro.different ways of treating bran by baking enzymes prior to dough making and the baking process were used to increase the amount of water-soluble dietary fiber (df) in wheat bread with added bran. soluble df was extracted from the bread with water and separated from the digestible material with gastrointestinal tract enzymes and by solvent precipitation. the baking enzyme mixtures tested (xylanase and glucanase/cellulase, with and without lipase) increased the amounts of soluble arabinoxylan and ...201222790935
oxygen tolerance in anaerobic pathogenic bacteria.a prerequisite for successful identification of anaerobic pathogenic bacteria from samples of clinical material is the method of cultivation. currently, several methods of cultivation in anaerobic environment are used: cultivation in anaerobic box, anaerobic jar, and in nonrecurring cultivation system. here, we determined the suitability of the above methods of cultivation using the estimation of the growth (diameters of colony size) of commonly isolated anaerobic pathogens (bacteroides fragilis ...201222573259
[diagnosis and control of human food poisoning outbreaks].medical microbiology laboratories play a key role in the investigation of foodborne disease outbreaks. bacterial pathogens (salmonella, escherichia coli, campylobacter, staphylococcus aureus, bacillus cereus, clostridium perfringens, etc) have historically been implicated in foodborne illness, while the role of viruses (especially norovirus) appears to have been underestimated. culture-based diagnosis has gradually been complemented, or replaced, by rapid molecular methods applied directly to bi ...201224313020
phytochemical profiles of volatile constituents from centaurea ragusina leaves and flowers and their antimicrobial effects.the volatile oils obtained from the leaves and flowers of the croatian endemic plant centaurea ragusina l. were evaluated for antimicrobial activity. the chemical compositions, determined by gc and gc-ms, were complex, with sesquiterpenes the most abundant class of compound. nonterpene hydrocarbons were also identified in high quantities, while acids and ketones were found in high quantities only in the leaf volatile oil. aldehydes, alcohols, esters and other compounds were identified in lower q ...201222978236
prevalence of staphylococcus aureus and methicillin-resistant s. aureus (mrsa) in food samples associated with foodborne illness in alberta, canada from 2007 to 2010.consumption of foods containing staphylococcus aureus can cause severe gastro-intestinal illness. given the fact that over the past decade, canada has seen increasing rates of methicillin-resistant s. aureus (mrsa) carriage and infection, the objective of this study was to investigate the impact of methicillin-susceptible s. aureus (mssa) and mrsa on foodborne illness in alberta, canada. between january 2007 and december 2010, there were 693 food samples associated with foodborne investigations ...201222850394
foodborne outbreaks surveillance in the piedmont region, italy (2002-2009).this article summarises the results of eight years (2002-2009) of investigations on food borne disease outbreaks carried out the regional agency for public health in piedmont, which is an italian region (4,432,571 citizens, 2008).201222508645
assessment of microbial quality of commercial and home-made tiger-nut beverages.we aimed to assess the microbiological quality of spanish commercial tiger-nut beverages as well as home-made samples collected from supermarkets, street vendors, juice bars and ice-cream parlours located in valencia.201222283438
interactions of high-affinity cationic blockers with the translocation pores of b. anthracis, c. botulinum, and c. perfringens binary toxins.cationic β-cyclodextrin derivatives were recently introduced as highly effective, potentially universal blockers of three binary bacterial toxins: anthrax toxin of bacillus anthracis, c2 toxin of clostridium botulinum, and iota toxin of clostridium perfringens. the binary toxins are made of two separate components: the enzymatic a component, which acts on certain intracellular targets, and the binding/translocation b component, which forms oligomeric channels in the target cell membrane. here we ...201222995493
bacteria and their toxins tamed for immunotherapy.bacterial toxins share the ability to enter host cells to target various intracellular proteins and to modulate host immune responses. over the last 20 years, toxins and their mutated variants, as well as live attenuated bacteria, have been exploited for vaccination and immunotherapy of various infectious, malignant and autoimmune diseases. the ability of bordetella pertussis adenylate cyclase toxin to translocate its adenylate cyclase domain across the host cell membrane, as well as the pathway ...201222339216
microbiologic characteristics of pathogenic bacteria from hospitalized trauma patients who survived wenchuan earthquake.the purpose of this study is to investigate the microbiological characterization of pathogenic bacteria isolated from trauma patients after wenchuan earthquake in 2008. most infections were identified in the patients over 60 years of age, with an incidence rate of 78.5%, and more infections in wound (43.3%) and respiratory tract (37.1%) sites were identified. a total of 97 non-duplicated clinical pathogens were isolated from 91 trauma patients. of those pathogens, 62 (63.9%) were gram-negative b ...201222910807
opportunistic pathogens and faecal indicators in drinking water associated biofilms in cluj, romania.biofouling occurs without exception in all water systems, with undesirable effects such as biocorrosion and deterioration of water quality. drinking water associated biofilms represent a potential risk to human health by harbouring pathogenic or toxin-releasing microorganisms. this is the first study investigating the attached microbiota, with potential threat to human health, in a public water system in romania. the presence and the seasonal variation of viable faecal indicators and opportunist ...201222960491
coenzyme depletion by members of the aerolysin family of pore-forming toxins leads to diminished atp levels and cell death.recent studies demonstrated that a variety of bacterial pore-forming toxins induce cell death through a process of programmed necrosis characterized by the rapid depletion of cellular atp. however, events leading to the necrosis and depletion of atp are not thoroughly understood. we demonstrate that atp-depletion induced by two pore-forming toxins, the clostridium perfringens epsilon-toxin and the aeromonas hydrophila aerolysin toxin, is associated with decreased mitochondrial membrane potential ...201222688384
efficacy of protected sodium butyrate, a protected blend of essential oils, their combination, and bacillus amyloliquefaciens spore suspension against artificially induced necrotic enteritis in broilers.necrotic enteritis caused by clostridium perfringens leads to serious economical losses to the poultry industry. there is a growing need to find effective, nontoxic, antibiotic alternatives to prevent and cure the disease. in our study, the efficacy of protected sodium butyrate at 1.5 g/kg (bp70), a bacillus amyloliquefaciens spore suspension with 10(9) cfu/g (bal; ecobiol), a protected blend of essential oils (1%) at 1.5 g/kg (eo), and a combination of sodium butyrate with essential oils (1%) p ...201222399722
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