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association between avian necrotic enteritis and clostridium perfringens strains expressing netb toxin.a novel toxin, netb, has recently been identified in virulent avian clostridium perfringens isolates and shown to be an essential virulence factor in a clinical necrotic enteritis isolate. to assess whether netb is more generally associated with avian necrotic enteritis isolates we have screened a range of c. perfringens strains from geographically diverse locations for both the presence and expression of the netb gene. forty-four isolates were derived from necrotic enteritis disease cases from ...201019931005
virulence of clostridium perfringens in an experimental model of poultry necrotic enteritis.poultry necrotic enteritis (ne) has, over recent decades, been prevented and treated by addition of antimicrobials to poultry feed. recent bans of antimicrobial growth promoters in feed, as well as other factors, have led to a slow, worldwide re-emergence of ne. understanding of pathogenesis of ne has been hampered by lack of a consistent and effective experimental model in which virulence of strains can be reliably evaluated, with an endpoint yielding lesions comparable to those seen in acute n ...201019931323
slec is essential for germination of clostridium difficile spores in nutrient-rich medium supplemented with the bile salt taurocholate.clostridium difficile is the major cause of infectious diarrhea and a major burden to health care services. the ability of this organism to form endospores plays a pivotal role in infection and disease transmission. spores are highly resistant to many forms of disinfection and thus are able to persist on hospital surfaces and disseminate infection. in order to cause disease, the spores must germinate and the organism must grow vegetatively. spore germination in bacillus is well understood, and g ...201019933358
clostridium perfringens in retail chicken.clostridium perfringens isolates were recovered by enrichment from retail grocery chicken samples (n = 88) in ontario, canada, with one sample per site. the gene associated with necrotic enteritis in chickens, netb, was found in 21% of the isolates. the tpel gene was found in 2% and the cpb2 gene in 68% (95% "atypical" genes) of isolates. this study suggests that netb-positive c. perfringens can reach people through retail chicken.201019961943
presence of pathogens and indicator microbes at a non-point source subtropical recreational marine beach.swimming in ocean water, including ocean water at beaches not impacted by known point sources of pollution, is an increasing health concern. this study was an initial evaluation of the presence of indicator microbes and pathogens and the association among the indicator microbes, pathogens, and environmental conditions at a subtropical, recreational marine beach in south florida impacted by non-point sources of pollution. twelve water and eight sand samples were collected during four sampling eve ...201019966020
etfa catalyses the formation of dipicolinic acid in clostridium perfringens.dipicolinic acid (dpa) is a major component of bacterial endospores, comprising 5-15% of the spore dry weight, and is important for spore stability and resistance properties. the biosynthetic precursor to dpa, dihydro-dipicolinic acid (dhdpa), is produced by dhdpa synthase within the lysine biosynthesis pathway. in bacillus subtilis, and most other bacilli and clostridia, dhdpa is oxidized to dpa by the products of the spovf operon. analysis of the genomes of the clostridia in cluster i, includi ...201019968785
a live oral recombinant salmonella enterica serovar typhimurium vaccine expressing clostridium perfringens antigens confers protection against necrotic enteritis in broiler chickens.necrotic enteritis (ne) in broiler chickens is caused by clostridium perfringens, and there is currently no effective vaccine for ne. we previously showed that in broiler chickens protection against ne can be achieved through intramuscular immunization with alpha toxin (at) and hypothetical protein (hp), and we subsequently identified b-cell epitopes in hp. in the present study, we identified b-cell epitopes in at recognized by chickens immune to ne. the gene fragments encoding immunodominant ep ...201020007363
effect of dietary protein concentrates on the incidence of subclinical necrotic enteritis and growth performance of broiler chickens.an experiment was conducted to quantify the effects of 3 nutritionally complete (similar protein and energy) corn-based diets that contained different dietary protein concentrates (potato-cp 76%, fish-cp 66%, or a mixture of soy proteins, soybean meal-cp 48%, and full-fat soy-cp 36%) on the incidence of spontaneously occurring subclinical necrotic enteritis (ne) in broiler chickens. a total of 1,260 birds were placed into 18 solid floor pens (70 birds per pen) and fed 1 of the 3 experimental die ...201020008800
comparison of the presence and partitioning behavior of indicator organisms and salmonella spp. in an urban watershed.the appropriateness of indicator organisms as surrogates for human pathogens in water quality modeling is dependent on similarities in both presence and transport behavior; however, very little data relating indicator and bacterial pathogen transport behavior in receiving waters is available. in this study observations of presence, partitioning behavior (i.e. association with settleable particles) and removal by upland detention basins were used to assess the suitability of six indicator organis ...201020009247
expanding the family of collagen proteins: recombinant bacterial collagens of varying composition form triple-helices of similar stability.the presence of the (gly-xaa-yaa)(n) open reading frames in different bacteria predicts the existence of an expanded family of collagen-like proteins. to further explore the triple-helix motif and stabilization mechanisms in the absence of hydroxyproline (hyp), predicted novel collagen-like proteins from gram-positive and -negative bacteria were expressed in escherichia coli and characterized. soluble proteins capable of successful folding and in vitro refolding were observed for collagen protei ...201020025291
screening-based discovery of drug-like o-glcnacase inhibitor scaffolds.o-glcnacylation is an essential posttranslational modification in metazoa. modulation of o-glcnac levels with small molecule inhibitors of o-glcnac hydrolase (oga) is a useful strategy to probe the role of this modification in a range of cellular processes. here we report the discovery of novel, low molecular weight and drug-like o-glcnacase inhibitor scaffolds by high-throughput screening. kinetic and x-ray crystallographic analyses of the binding modes with human/bacterial o-glcnacases identif ...201020026047
preliminary report on anaerobic culture at mymensingh medical college hospital in bangladesh.puerperal sepsis is an important cause of maternal morbidity and mortality in developing countries. this study was undertaken to isolate and identify the anaerobic bacterial agents of puerperal sepsis among the patients admitted in mymensingh medical college hospital (mmch) during the period from july 2006 to june 2007. endocervical swabs/secretions were collected from 50 cases of puerperal sepsis and were cultured anaerobically. anaerobiasis was done by using gas pack (bd gas pak tm ez) in anae ...201020046165
bacteriological characterization of wastewater samples obtained from a primary treatment system on a small scale swine farm.this study was carried out in order to quantify enteric bacteria and identify the presence of salmonella spp., escherichiacoli, clostridiumperfringens and erysipelothixrhusiopathiae in the liquid fraction of excreta generated from a small scale swine farm by means of a primary treatment system, consisting of the separation of solids and the sedimentation of liquids. samples were collected at the following stages of the treatment: collection basin (cb), liquid obtained from a solids separator (sl ...201020053557
genetic diversity and prevalence of netb in clostridium perfringens isolated from a broiler flock affected by mild necrotic enteritis.this study was undertaken to examine the genetic diversity of clostridium perfringens isolated from a single broiler flock reared without in-feed antimicrobials (antibacterial growth promoters and anticoccidials) and affected by mild necrotic enteritis (ne). we used pulsed-field gel electrophoresis (pfge) to investigate the genetic diversity of c. perfringens isolates from broilers of varying disease status, and from litter. the prevalence of the toxin gene netb was also investigated. altogether ...201020056357
massive intravascular haemolysis during clostridium perfrigens sepsis of hepatic origin. 201019682059
prevalence, prediction and risk factors of enteropathogens in normal and non-normal faeces of young dutch dairy calves.between january and april 2007, 424 calves under 22 days of age from 108 dutch dairy herds were sampled to estimate the prevalence of non-normal faeces ('custard-like'-yellowish-coloured with custard consistency or diarrhoea: watery-like faeces) and the shedding of enteropathogens escherichia coli k99 (e. coli), coronavirus, cryptosporidium parvum (c. parvum), rotavirus and clostridium perfringens (cl. perfringens). in addition, information was collected on animal characteristics and herd-manage ...201019819574
genetic and biochemical analysis of a class c non-specific acid phosphatase (nsap) of clostridium perfringens.clostridium perfringens, a gram-positive anaerobe, is a human pathogen that causes gas gangrene in muscle tissues. its ability to grow and survive in the host is believed to be due to the production of numerous enzymes that enable the organism to obtain essential nutrients from the host. in this study, cpe0201, a putative acid phosphatase gene deduced by genome analysis, was shown to encode a non-specific acid phosphatase in c. perfringens. multiple alignments of the amino acid sequence showed t ...201019833778
identification of a two-component virr/virs regulon in clostridium perfringens.clostridium perfringens, a gram-positive anaerobic pathogen, is a causative agent of human gas gangrene that leads to severe rapid tissue destruction and can cause death within hours unless treated immediately. production of several toxins is known to be controlled by the two-component virr/virs system involving a regulatory rna (vr-rna) in c. perfringens. to elucidate the precise regulatory network governed by virr/virs and vr-rna, a series of microarray screening using virr/virs and vr-rna-def ...201019835966
beta-catenin expression and claudin expression pattern as prognostic factors of prostatic cancer progression.to investigate the patterns of expression of the junctional proteins beta-catenin and claudins in different prognostic groups of patients with prostatic cancer, to determine their value as prognostic markers.201019818082
pathema: a clade-specific bioinformatics resource center for pathogen research.pathema (http://pathema.jcvi.org) is one of the eight bioinformatics resource centers (brcs) funded by the national institute of allergy and infectious disease (niaid) designed to serve as a core resource for the bio-defense and infectious disease research community. pathema strives to support basic research and accelerate scientific progress for understanding, detecting, diagnosing and treating an established set of six target niaid category a-c pathogens: category a priority pathogens; bacillu ...201019843611
characterization of virulence plasmid diversity among clostridium perfringens type b isolates.the important veterinary pathogen clostridium perfringens type b is unique for producing the two most lethal c. perfringens toxins, i.e., epsilon-toxin and beta-toxin. our recent study (k. miyamoto, j. li, s. sayeed, s. akimoto, and b. a. mcclane, j. bacteriol. 190:7178-7188, 2008) showed that most, if not all, type b isolates carry a 65-kb epsilon-toxin-encoding plasmid. however, this epsilon-toxin plasmid did not possess the cpb gene encoding beta-toxin, suggesting that type b isolates carry a ...201019858300
identification of a claudin-4 residue important for mediating the host cell binding and action of clostridium perfringens enterotoxin.the 24-member claudin protein family plays a key role in maintaining the normal structure and function of epithelial tight junctions. previous studies with fibroblast transfectants and naturally sensitive caco-2 cells have also implicated certain claudins (e.g., claudin-4) as receptors for clostridium perfringens enterotoxin (cpe). the present study first provided evidence that the second extracellular loop (ecl-2) of claudins is specifically important for mediating the host cell binding and cyt ...201019884339
clostridium perfringens enterotoxin interacts with claudins via electrostatic attraction.clostridium perfringens enterotoxin (cpe), a causative agent of food poisoning, is a pore-forming toxin disrupting the selective permeability of the plasma membrane of target cells, resulting in cell death. we previously identified claudin as the cell surface receptor for cpe. claudin, a component of tight junctions, is a tetratransmembrane protein and constitutes a large family of more than 20 members, not all of which serve as the receptor for cpe. the mechanism by which the toxin distinguishe ...201019903817
role of host cell polarity and leading edge properties in pseudomonas type iii secretion.type iii secretion (t3s) functions in establishing infections in a large number of gram-negative bacteria, yet little is known about how host cell properties might function in this process. we used the opportunistic pathogen pseudomonas aeruginosa and the ability to alter host cell sensitivity to pseudomonas t3s to explore this problem. ht-29 epithelial cells were used to study cellular changes associated with loss of t3s sensitivity, which could be induced by treatment with methyl-beta-cyclodex ...201019910414
mucosal delivery of antigens using adsorption to bacterial spores.the development of new-generation vaccines has followed a number of strategic avenues including the use of live recombinant bacteria. of these, the use of genetically engineered bacterial spores has been shown to offer promise as both a mucosal as well as a heat-stable vaccine delivery system. spores of the genus bacillus are currently in widespread use as probiotics enabling a case to be made for their safety. in this work we have discovered that the negatively charged and hydrophobic surface l ...201019914191
qpcr quantification and genetic characterization of clostridium perfringens populations in biosolids composted for 2 years.the ability of clostridium perfringens to survive for a long time in the environment makes it a suitable indicator of faecal pollution, but its use as a routine indicator organism in biosolids and composted biosolids has not yet been adopted. this study was performed to improve our understanding of c. perfringens persistence in composted biosolids by monitoring its presence and studying its genetic diversity.201019645764
identification of changes in the composition of ileal bacterial microbiota of broiler chickens infected with clostridium perfringens.we previously reported that clostridium perfringens in vivo proliferation and alpha-toxin gene expression were highly correlated, both progressing in a parabolic curve pattern during the development of necrotic enteritis (ne). the present study investigated the response of dominant ileal bacteria in abundance to c. perfringens infection using pcr-based denaturing gradient gel electrophoresis (dgge) and quantitative pcr (qpcr) techniques. chickens were fed antibiotic-medicated (bacitracin, 55 mg/ ...201019647376
upper gastrointestinal bleeding related to emphysematous cholecystitis due to clostridium perfringens.we describe the case of a 46-year-old man admitted for upper gastrointestinal bleeding in the context of cirrhosis. a deep bleeding duodenal ulcer was treated by sclerotherapy. abdominal pain and fever lead us to perform an abdominal computed tomography, which demonstrated emphysematous cholecystitis. an emergency cholecystectomy was performed and antimicrobial therapy initiated. the patient recovered uneventfully. links between ulcers and emphysematous cholecystitis are discussed.201019660973
clostridia as agents of zoonotic disease.clostridia are not normally considered to be zoonotic pathogens, although many species affect both humans and domestic animals. three cases in which organisms occur, possibly via direct or indirect transmission, in both food animals and humans are considered here. strains of clostridium perfringens that produce enterotoxin (cpe) are typically transmitted to humans in contaminated, improperly handled foods. pathogenesis is based upon action of cpe in the intestine, and disease is usually self-lim ...201019682805
mammalian cell ganglioside-binding specificities of e. coli enterotoxins lt-iib and variant lt-iib(t13i).lt-iib, a type ii heat-labile enterotoxin of escherichia coli, is a potent immunologic adjuvant with high affinity binding for ganglioside gd1a. earlier study suggested that lt-iib bound preferentially to the terminal sugar sequence neuacalpha2-3galbeta1-3galnac. however, studies in our laboratory suggested a less restrictive binding epitope. lt-iib(t13i), an lt-iib variant, engineered by a single isoleucine-threonine substitution, retains biological activity, but with less robust inflammatory e ...201019749203
enteric bacterial pathogen detection in southern sea otters (enhydra lutris nereis) is associated with coastal urbanization and freshwater runoff.although protected for nearly a century, california's sea otters have been slow to recover, in part due to exposure to fecally-associated protozoal pathogens like toxoplasma gondii and sarcocystis neurona. however, potential impacts from exposure to fecal bacteria have not been systematically explored. using selective media, we examined feces from live and dead sea otters from california for specific enteric bacterial pathogens (campylobacter, salmonella, clostridium perfringens, c. difficile an ...201019720009
nitric oxide and lysozyme production as an impact to clostridium perfringens mastitis.the anaerobic mastitis incidence was used to study the bovine udder response in anaerobic bacterial mastitis caused by the gram-positive bacterial strain of clostridium perfringens. milk samples positive for c. perfringens were assayed for no and lysozyme. the model produced a strong no and lysozyme response which correlated positively with the severity and outcome of the disease (subclinical and clinical stages). this study is, to our knowledge, the first to suggest a possible link between no a ...201019783303
potential for growth of clostridium perfringens from spores in pork scrapple during cooling.we conducted stabilization studies to determine the ability of clostridium perfringens spores to germinate and grow during exponential cooling of a commercial formulation of pork scrapple. scrapple was inoculated with a mixture of three strains of c. perfringens spores (ntcc 8238, nctc 8239, and atcc 10288), vacuum packaged, and reheated (20 min/93.3 degrees c) in a circulating water bath. the cooked samples were cooled (30 s) in an ice bath before being transferred to a programmable water bath ...201019785539
the occurrence of cpb2-toxigenic clostridium perfringens and the possible role of the beta2-toxin in enteric disease of domestic animals, wild animals and humans.the virulence of clostridium perfringens, a bacterium causing enteritis and enterotoxaemia in domestic and wild animals and humans, results largely from its ability to produce toxins. in 1997, an unknown toxin of c. perfringens, the beta2-toxin, and its encoding gene cpb2 were described. since that time numerous studies have been published dealing with a possible association of cpb2-harbouring strains of c. perfringens and the occurrence of enteric disease in domestic and wild animals and humans ...201019101180
netb, a pore-forming toxin from necrotic enteritis strains of clostridium perfringens.the clostridium perfringens necrotic enteritis b-like toxin (netb) is a recently discovered member of the ß-barrel pore-forming toxin family and is produced by a subset of avian c. perfringens type a strains. netb is cytotoxic for avian cells and is associated with avian necrotic enteritis. this review examines the current state of knowledge of netb: its role in pathogenesis, its distribution and expression in c. perfringens and its vaccine potential.201022069665
bug breakfast in the bulletin: gastroenteritis outbreaks in institutions. 201021426853
[risks occurring during the use of raw medicinal plant material and its based phytopreparations].to enhance the informative value of evaluation of the microbiological purity of raw medicinal plant material and its based preparations, the authors estimated the total number of bacteria by the modified method and determined whether clostridium perfringens might be present in the samples. a higher level of pollution of plant preparations was noted than that detectable according to the pharmacopoeia. clostridia were present not only in the raw plant material, but also in its infusions and decoct ...201021381368
investigation of haemorrhagic enteritis in pygmy hogs (sus salvanius) from india.the pygmy hog is a representative of the smallest and rarest wild species of known living suidae. this paper reports the investigation of haemorrhagic enteritis encountered amongst the pygmy hogs at the research and breeding centre of the pygmy hog conservation programme, guwahati, assam, india. three out of 68 pygmy hogs died of enteric infection. post-mortem examination and bacteriological investigation of two out of the three animals that died revealed clostridial infection. the isolates harb ...201021309467
effect of a radiant energy-treated lysozyme antimicrobial blend on the control of clostridial necrotic enteritis in broiler chickens.a cage study was conducted to demonstrate the effect of entegard rev, a lysozyme-based antimicrobial blend, on the performance of broiler chickens and necrotic enteritis (ne) disease reduction of birds that were challenged with eimeria maxima and clostridium perfringens. in the experiment, challenge by the infectious agents without medication resulted in impaired feed consumption, weight gain, and feed conversions and caused high incidence of gross ne lesions and ne mortality rate. entegard rev ...201021313853
role of clostridium perfringens in causing abomasal ulcers in buffalo.in this study, the correlation between abomasal ulcers and presence of clostridium perfringens (c. perfringens) was evaluated in 80 (50 affected and 30 non affected) randomly slaughtered buffaloes in ahvaz slaughterhouse. immediately after the slaughter, the abomasums was isolated and an incision was made on the wall of it. then the abomasums were emptied and its interior was washed with water. the inner surface was examined for presence of abnormal lesion. ulcers from affected and piece of abom ...201021313887
assessment of 2 salmonella enterica serovar typhimurium-based vaccines against necrotic enteritis in reducing colonization of chickens by salmonella serovars of different serogroups.this study assessed the protective efficacy of oral vaccination with 2 experimental attenuated salmonella typhimurium-vectored vaccines for necrotic enteritis in protecting chickens against intestinal colonization by common serovars of salmonella belonging to the 4 major serogroups affecting chickens. birds were vaccinated orally with 1 × 10⁸ colony-forming units (cfu) of 1 of the vaccine strains χ9241 and χ9352, which express a plasmid-encoded partial recombinant hypothetical protein gene (thp) ...201021197226
crystal structure of cytotoxin protein suilysin from streptococcus suis.cholesterol-dependent cytolysins (cdc) are pore forming toxins. a prototype of the cdc family members is perfringolysin o (pfo), which directly binds to the cell membrane enriched in cholesterol, causing cell lysis. however, an exception of this general observation is intermedilysin (ily) of streptococcus intermedius, which requires human cd59 as a receptor in addition to cholesterol for its hemolytic activity. a possible explanation of this functional difference is the conformational variation ...201021204001
effects of feeding distillers dried grains with solubles to broilers from 0 to 28 days posthatch on broiler performance, feed manufacturing efficiency, and selected intestinal characteristics.this study evaluated the effect of 2 levels (0 vs. 8%) of distillers dried grains with solubles (ddgs) in a starter broiler diet (0 to 14 d; 45 replicates/treatment) after these same birds were subsequently fed a grower diet (14 to 28 d) with either 0, 7.5, 15, 22.5, or 30% ddgs (9 replicates/treatment). ross×ross 308 male broilers were used in this experiment, and evaluation criteria consisted of feed mill parameters, broiler growth, relative liver weight, ileal viscosity, and cecal content cou ...201020852115
clostridium perfringens type c isolates rapidly upregulate their toxin production upon contact with host cells: new insights into virulence?since tetanus was first described by hippocrates, the devastating diseases caused by pathogenic members of the gram-positive, anaerobic sporeforming genus clostridium have ranked among the most dreaded afflictions of humans and domestic animals. the quintessential hallmark of all clostridial diseases is the involvement of potent protein toxins. however, except for some foodborne botulism cases, clostridial diseases are not intoxications involving preformed toxins; rather, these illnesses are tru ...201021178424
development and application of a method for counterselectable in-frame deletion in clostridium perfringens.many pathogenic clostridial species produce toxins and enzymes. to facilitate genome-wide identification of virulence factors and biotechnological application of their useful products, we have developed a markerless in-frame deletion method for clostridium perfringens which allows efficient counterselection and multiple-gene disruption. the system comprises a galkt gene disruptant and a suicide galk plasmid into which two fragments of a target gene for in-frame deletion are cloned. the system wa ...201021183644
[current clinical significance of anaerobic bacteremia].to estimate tje current clinical significance of anaerobic bacteremia in a group of czech hospitals.201021191873
the genome sequence and proteome of bacteriophage φcpv1 virulent for clostridium perfringens.application of bacteriophages and their lytic enzymes to control clostridium perfringens is one potential approach to reduce the pathogen on poultry farms and in poultry-processing facilities. bacteriophages lytic for c. perfringens were isolated from sewage, feces and broiler intestinal contents and φcpv1, a virulent bacteriophage, was classified in the family podoviridae. the purified virus had an icosahedral head and collar of approximately 42nm and 23nm in diameter, respectively, with a stru ...201021144870
real-time pcr assay for clostridium perfringens in broiler chickens in a challenge model of necrotic enteritis.we compared ileal clostridium perfringens quantification results produced by real-time pcr and culture-based methods in broiler chickens in a challenge model of necrotic enteritis. assessment of the relative standard deviations (rsds) revealed that the real-time pcr assay generated a smaller standard deviation and thus was more precise than the culture-based method. linear regression analysis indicated that the bacterial counts of these two methods were highly correlated (r(2) = 0.845). we sugge ...201021148703
toxinotyping of necrotic enteritis-producing and commensal isolates of clostridium perfringens from chickens fed organic diets.the present study determined the effect of clostridium perfringens isolates taken from necrotic enteritis (ne) outbreaks on organic farms in a ne virulence testing model. thirteen strains were isolated in the course of the study. six c. perfringens field isolates were taken from a naturally occurring ne outbreak on an organic farm. polymerase chain reaction toxinotyping was used to establish c. perfringens strains, as well as to create a toxin profile. all field isolates were found to be type a ...201021154057
safety and efficacy of a maternal vaccine for the passive protection of broiler chicks against necrotic enteritis.necrotic enteritis is a potentially fatal multifactorial disease of chickens, which under commercial conditions is often associated with increased levels of mortality and reduced bird performance. the safety and efficacy of a clostridium perfringens type a alpha-toxoid (netvax™) formulated as an oil emulsion was investigated, following maternal immunization of broiler breeder hens, housed under commercial conditions, by the intramuscular route. a total of 11,234 hens were vaccinated across two i ...201021154059
fecal lactoferrin and clostridium spp. in stools of autistic children.stools from autistic and healthy children were studied for fecal lactoferrin, clostridium difficile toxins, clostridium perfringens enterotoxin and cultured for clostridium spp. elevated level of fla was demonstrated in 24.4% stools, all from boys (31.25%). no toxins were detected. clostridium spp. was isolated with similar frequency from all samples. c. perfringens were isolated significantly often from the autistic stools, intermediate sensitive strains to penicillin 19%, to clindamycin 11.3%, ...201021167951
glycoside hydrolase family 89 alpha-n-acetylglucosaminidase from clostridium perfringens specifically acts on glcnac alpha1,4gal beta1r at the non-reducing terminus of o-glycans in gastric mucin.in mammals, α-linked glcnac is primarily found in heparan sulfate/heparin and gastric gland mucous cell type mucin. α-n-acetylglucosaminidases (αgnases) belonging to glycoside hydrolase family 89 are widely distributed from bacteria to higher eukaryotes. human lysosomal αgnase is well known to degrade heparin and heparan sulfate. here, we reveal the substrate specificity of αgnase (agnc) from clostridium perfringens strain 13, a bacterial homolog of human αgnase, by chemically synthesizing a ser ...201021177247
intravascular haemolysis and septicaemia due to clostridium perfringens liver abscess.intravascular haemolysis is a rare but serious complication of clostridium perfringens sepsis. the outcome is usually fatal unless treatment is started early. we describe a case of survival after haemolysis and multiple organ failure in the setting of a ruptured liver abscess and sepsis caused by c. perfringens in an immunocompetent 58-year-old male.201020865884
clostridium perfringens septicaemia with massive intravascular haemolysis: a case report and review of the literature.we describe the case of a 74-year-old man with cholangitis, complicated by clostridium perfringens septicaemia and massive intravascular haemolysis. clostridium perfringens septicaemia is a rare but well-known cause of massive intravascular haemolysis. here we review 40 similar cases published since 1990. most cases involve immunocompromised patients with underlying haematological disorder (22.5%), pancreatic or gastric cancer (12.5%) and÷or diabetes (30.0%). focus of infection is mostly hepatob ...201020876913
phospholipid hydrolysis caused by clostridium perfringens α-toxin facilitates the targeting of perfringolysin o to membrane bilayers.clostridium perfringens causes gas gangrene and gastrointestinal disease in humans. these pathologies are mediated by potent extracellular protein toxins, particularly α-toxin and perfringolysin o (pfo). while α-toxin hydrolyzes phosphatidylcholine and sphingomyelin, pfo forms large transmembrane pores on cholesterol-containing membranes. it has been suggested that the ability of pfo to perforate the membrane of target cells is dictated by how much free cholesterol molecules are present. given t ...201020886855
isolation of culturable microorganisms from free-ranging bottlenose dolphins (tursiops truncatus) from the southeastern united states.reports of diseases in marine mammals are increasing worldwide, however our understanding of the microorganisms associated with marine mammals is still limited. in this study, we cultured bacteria and fungi isolated from the upper respiratory tract (blowhole), gastric fluid and anus of 180 wild bottlenose dolphins (tursiops truncatus) from two estuarine locations along the southeastern atlantic coast of the united states. a total of 339 and 491 isolates from charleston, sc (chs) and indian river ...201020888150
neuroprotective effect of cpdt on tha-induced cortical motor neuron death in an organotypic culture model.brain stroke, trauma, and motor neuron disease each can result in cortical motoneuron (cmn) death or impairment. glutamate excitotoxicity induces motor neuron damage in both acute motor neuron loss and chronic motor neuron degeneration. it is necessary to find effective strategies to protect cmns from excitotoxicity in a variety of pathological conditions. 5,6-dihydrocyclopenta-1,2-dithiole-3-thione (cpdt) is one of the phase ii enzyme inducers. in our previous report, cpdt was shown to have neu ...201020851746
base pair specificity and energetics of binding of the phenazinium molecules phenosafranine and safranine-o to deoxyribonucleic acids: a comparative study.the base specificity and energetics of dna binding of the phenazinium dyes phenosafranine and safranine-o have been studied using various biophysical tools. the guanine-cytosine base specificity of both compounds was established from binding affinity values and competition dialysis results and also from circular dichroism, thermal melting, and calorimetric studies. both dyes bind to dna with affinity of the order of 10(5) m(-1), but the values are significantly higher for the guanine-cytosine ri ...201020730145
[microbiological evaluation of ready-to-eat foods manufactured by small costa rican industries].ready-to-eat (rte) foods are processed foodstuffs which have gained popularity in recent times because they can be ingested without further thermic treatments. in this work, the microbiological quality and safety of 90 samples of rte foods manufactured by small costa rican industries was determined to evaluate whether they represent a public health risk. twenty-six samples of pickled vegetables, 18 dips, 18 salads, and 12 sweet treats were studied. each sample was analyzed with regard to its ph, ...201021427886
synergistic antimicrobial activity of galangal (alpinia galanga), rosemary (rosmarinus officinalis) and lemon iron bark (eucalyptus staigerana) extracts.in this study the synergistic antimicrobial activities of combinations of extracts from galangal (alpinia galanga), rosemary (rosmarinus officinalis) and lemon iron bark (eucalyptus staigerana) were evaluated against staphylococcus aureus, listeria monocytogenes, escherichia coli, salmonella typhimurium and clostridium perfringens. chemical compositions of these extracts were also determined to provide further insight into antimicrobial constituents and their potential mechanisms of action.201021218479
novel insights into the epidemiology of clostridium perfringens type a food poisoning.clostridium perfringens food poisoning ranks among the most common gastrointestinal diseases in developed countries. the disease is caused by c. perfringens enterotoxin (cpe) encoded by cpe and produced by less than 5% of c. perfringens type a strains. molecular epidemiological research in the past 15 years has focused on the reservoirs and routes of cpe-positive c. perfringens aiming to clarify the role and epidemiology of chromosomal and plasmid-borne cpe-carrying strains. this literature revi ...201021315973
clostridial spore germination versus bacilli: genome mining and current insights.bacilli and clostridia share the characteristic of forming metabolically inactive endospores. spores are highly resistant to adverse environmental conditions including heat, and their ubiquitous presence in nature makes them inevitable contaminants of foods and food ingredients. spores can germinate under favourable conditions, and the following outgrowth can lead to food spoilage and foodborne illness. germination of spores has been best studied in bacillus species, but the process of spore ger ...201021315983
bayesian modeling of clostridium perfringens growth in beef-in-sauce products.models on clostridium perfringens growth which have been published to date have all been deterministic. a probabilistic model describing growth under non-isothermal conditions was thus proposed for predicting c. perfringens growth in beef-in-sauce products cooked and distributed in a french hospital. model parameters were estimated from different types of data from various studies. a bayesian approach was proposed to model the overall uncertainty regarding parameters and potential variability on ...201021315989
possibility of preventing colorectal carcinogenesis with probiotics.there have been no reports on the relationship between the analyses of the intestinal flora of colorectal cancer patients and colorectal carcinogenesis. in this study we investigated the differences between the intestinal flora of colorectal cancer patients and healthy subjects and assessed the possibility of using probiotics to prevent colorectal carcinogenesis.201021443095
specificity of interaction between clostridium perfringens enterotoxin and claudin-family tight junction proteins.clostridium perfringens enterotoxin (cpe), a major cause of food poisoning, forms physical pores in the plasma membrane of intestinal epithelial cells. the ability of cpe to recognize the epithelium is due to the c-terminal binding domain, which binds to a specific motif on the second extracellular loop of tight junction proteins known as claudins. the interaction between claudins and cpe plays a key role in mediating cpe toxicity by facilitating pore formation and by promoting tight junction di ...201022069652
on the interaction of clostridium perfringens enterotoxin with claudins.clostridium perfringens causes one of the most common foodborne illnesses, which is largely mediated by the clostridium perfringens enterotoxin (cpe). the toxin consists of two functional domains. the n-terminal region mediates the cytotoxic effect through pore formation in the plasma membrane of the mammalian host cell. the c-terminal region (ccpe) binds to the second extracellular loop of a subset of claudins. claudin-3 and claudin-4 have been shown to be receptors for cpe with very high affin ...201022069641
clostridium perfringens iota-toxin: structure and function.clostridium perfringens iota-toxin is composed of the enzyme component (ia) and the binding component (ib). ib binds to receptor on targeted cells and translocates ia into the cytosol of the cells. ia adp-ribosylates actin, resulting in cell rounding and death. comparisons of the deduced amino acid sequence from the gene and three-dimensional structure of ia with those of adp-ribosylating toxins (arts) suggests that there is striking structural similarity among these toxins. our objectives are t ...200922069542
acute diarrhoea: an unusual presentation.an obese diabetic male presented with self limiting diarrhoea of 1 day duration, which had started after he ate sausages. examination was unrevealing except for persistent low blood pressure. computed tomographic (ct) scan, done to rule out retroperitoneal bleed, incidentally showed air in the gall bladder. he underwent emergent cholecystectomy, and a gangrenous gall bladder that grew clostridium perfringens was removed. emphysematous cholecystitis is not so infrequent, although only rarely does ...200921686790
clostridium perfringens endophthalmitis following perforating eye injury.a 59-year-old man presented with endophthalmitis, following a perforating eye injury from pulling out a wire that was embedded in the ground. on presentation, his vision was perception of light (pl). tetanus toxoid was given, and he was commenced on ciprofloxacin. a primary repair was performed. conjunctival swabs, discharge from wound site and anterior chamber aspirate were sent for culture. the eye was tense and the anterior chamber was full of a gelatinous brown substance which precluded perf ...200921747903
assessment of the microbiological safety of dried spices and herbs from production and retail premises in the united kingdom.a study of dried spices and herbs from retail and production premises to determine the microbiological status of such products was undertaken in the uk during 2004. according to ec recommendation 2004/24/ec and european spice association specifications, 96% of 2833 retail samples and 92% of 132 production batches were of satisfactory/acceptable quality. salmonella spp. were detected in 1.5% and 1.1% of dried spices and herbs sampled at production and retail, respectively. overall, 3.0% of herbs ...200919028303
detection and toxin typing of clostridium perfringens in formalin-fixed, paraffin-embedded tissue samples by pcr.since current microbiology methods are not suitable to detect clostridium perfringens in formalin-fixed, paraffin-embedded tissue samples, we developed a pcr assay to detect toxin-encoding genes and the 16s rrna gene of c. perfringens. we successfully detected and genotyped c. perfringens in tissue sections from two autopsy cases.200919109478
a conjugative macrolide resistance gene, mef(a), in environmental clostridium perfringens carrying multiple macrolide and/or tetracycline resistance genes.to determine if environmental clostridium perfringens carry antibiotic resistance genes and if the genes are mobile.200919120611
regional differences in bacterial flora in harbour porpoises from the north atlantic: environmental effects?microbiological findings in harbour porpoises from different regions of the north atlantic were compared. results in animals from the north and baltic seas were evaluated over a period of 18 years for changes in the microbiological flora.200919120613
bacterial neuraminidase increases il-8 production in lung epithelial cells via nf-kappab-dependent pathway.bacterial neuraminidase, a sialic acid-degrading enzyme, is one of the virulent factors produced in pathogenic bacteria like as other bacterial components. however little is known about whether bacterial neuraminidase can initiate or modify a cellular response, such as cytokine production, in epithelial cells at infection and inflammation. we demonstrate here that bacterial neuraminidase, but not heat-inactivated neuraminidase, up-regulates expression of interleukin-8 (il-8) mrna and protein in ...200919121622
ultrasound-induced inactivation of gram-negative and gram-positive bacteria in secondary treated municipal wastewater.the effect of 24khz, high energy ultrasound in the presence and absence of titanium dioxide particles on the destruction of different bacteria groups was studied. applying a total of 1500w/l for 60min (this corresponds to 5400kj/l specific nominal energy), the mean destruction of gram-negative bacteria such as total coliforms, faecal coliforms and pseudomonas spp. was 99.5%, 99.2% and 99.7%, respectively. more recalcitrant to sonolytic inactivation were the gram-positive bacteria clostridium per ...200919131265
rainfall simulation in greenhouse microcosms to assess bacterial-associated runoff from land-applied poultry litter.runoff water following a rain event is one possible source of environmental contamination after a manure application. this greenhouse study used a rainfall simulator to determine bacterial-associated runoff from troughs of common bermudagrass [cynodon dactylon (l.) pers.] that were treated with p-based, n-based, and n plus lime rates of poultry (gallus gallus) litter, recommended inorganic fertilizer, and control. total heterotrophic plate count (hpc) bacteria, total and thermotolerant coliforms ...200919141812
necrotizing pneumonia and sepsis due to clostridium perfringens: a case report.abstract: clostridia are uncommon causes of pleuropulmonary infection. clostridial species infecting the pleuropulmonary structures characteristically cause a necrotizing pneumonia with involvement of the pleura. most cases have iatrogenic causes usually due to invasive procedures into the pleural cavity, such as thoracentesis or thoracotomy, or penetrating chest injuries. rarely clostridia pleuropulmonary infections are not related to these factors. the clinical course of pleuropulmonary clostr ...200919144160
a multiplex pcr for toxin typing of clostridium perfringens isolates. 200919157726
auranofin disrupts selenium metabolism in clostridium difficile by forming a stable au-se adduct.clostridium difficile is a nosocomial pathogen whose incidence and importance are on the rise. previous work in our laboratory characterized the central role of selenoenzyme-dependent stickland reactions in c. difficile metabolism. in this work we have identified, using mass spectrometry, a stable complex formed upon reaction of auranofin (a gold-containing drug) with selenide in vitro. x-ray absorption spectroscopy supports the structure that we proposed on the basis of mass-spectrometric data. ...200919165513
rethinking our understanding of the pathogenesis of necrotic enteritis in chickens.for decades, low doses of antibiotics have been used widely in animal production to promote growth. however, there is a trend to reduce this use of antibiotics in feedstuffs, and legislation is now in place in europe to prohibit their use in this way. as a consequence, economically important diseases, such as necrotic enteritis (ne) of chickens, that are caused by clostridium perfringens have become more prevalent. recent research is creating a paradigm shift in our understanding of the pathogen ...200918977143
fate of pathogenic microorganisms and indicators in secondary activated sludge wastewater treatment plants.this study was undertaken to investigate the removal of pathogenic microorganisms and their indicators in a laboratory scale biological treatment system that simulated the secondary treatment process of a wastewater treatment plant (wwtp). four groups of microorganisms including bacteria, viruses, protozoa and helminths as well as the selected indicators were employed in the investigation. the results demonstrated that approximately 2-3 log10 removal of the microbial indicators was achieved in t ...200918977580
potential use of tight junction modulators to reversibly open membranous barriers and improve drug delivery.the epithelial and endothelial barriers of the human body are major obstacles for drug delivery to the systemic circulation and to organs with unique environment and homeostasis, like the central nervous system. several transport routes exist in these barriers, which potentially can be exploited for enhancing drug permeability. beside the transcellular pathways via transporters, adsorptive and receptor-mediated transcytosis, the paracellular flux for cells and molecules is very limited. while li ...200918983815
antimicrobial activity of essential oils and structurally related synthetic food additives towards clostridium perfringens.to assess the potential of essential oils and structurally related synthetic food additives in inhibiting the growth of clostridium perfringens for the control of necrotic enteritis in chickens.200919054237
extracellular protectants produced by clostridium perfringens cells at elevated temperatures.the mechanisms of adaptation of clostridium perfringens to high temperatures are not well understood. in this work, the involvement of extracellular compounds in protection to heat was determined.200919055630
tight junctions as targets of infectious agents.the epithelial barrier is a critical border that segregates luminal material from entering tissues. essential components of this epithelial fence are physical intercellular structures termed tight junctions. these junctions use a variety of transmembrane proteins coupled with cytoplasmic adaptors, and the actin cytoskeleton, to attach adjacent cells together thereby forming intercellular seals. breaching of this barrier has profound effects on human health and disease, as barrier deficiencies ha ...200919059200
sequence variation in the alpha-toxin encoding plc gene of clostridium perfringens strains isolated from diseased and healthy chickens.the aim of the present study was to analyse the genetic diversity of the alpha-toxin encoding plc gene and the variation in alpha-toxin production of clostridium perfringens type a strains isolated from presumably healthy chickens and chickens suffering from either necrotic enteritis (ne) or cholangio-hepatitis. the alpha-toxin encoding plc genes from 60 different pulsed-field gel electrophoresis (pfge) types (strains) of c. perfringens were sequenced and translated in silico to amino acid seque ...200919070974
prevalence of netb among some clinical isolates of clostridium perfringens from animals in the united states.a previously unknown pore forming toxin, called netb toxin, which is produced by some australian strains of clostridium perfringens has recently been reported. this toxin was reported to be critical to the development of the disease necrotic enteritis, in chickens. to investigate the occurrence of the toxin gene (netb) in non-australian c. perfringens strains, one hundred and six american isolates of c. perfringens were examined. ninety-two isolates were from chickens, and 14 were from cattle. t ...200919081686
claudin expression in rectal well-differentiated endocrine neoplasms (carcinoid tumors).claudins are the structures and functional components of tight junctions and have crucial roles in the maintenance of cell polarity, cellular arrangement, adhesion and paracellular transport. various claudins are expressed in different epithelial cells and most tissues express multiple claudin proteins. the altered expression of claudins has been reported in various human carcinomas, but their expression in rectal well-differentiated endocrine neoplasms (carcinoid tumors), the most common endocr ...200919082451
[clostridial brain abscess after glioblastoma resection: case report and critical review of the literature].clostridium perfringens is rare in neurosurgery. the source of clostridial brain abscess is usually a penetrating head injury. we report the case of a 57-year-old man who had parietal glioblastoma resection with local carmustine chemotherapy and who presented a clostridial brain abscess three weeks later. progression was especially brutal, leading to patient's death in few hours. we discuss the etiology and progression of this case compared to the data reported in the literature.200919095271
effects of diet type and enzyme addition on growth performance and gut health of broiler chickens during subclinical clostridium perfringens challenge.the effects of diet type (corn- vs. wheat-based) and multicarbohydrase addition on growth performance, digesta ph and viscosity, intestinal populations of clostridium perfringens and lactic acid bacteria, and gut lesion score (from 0 to 4, where 0 = no gross lesions, 4 = severe extensive necrosis) of broiler chickens during oral challenge with c. perfringens (none or 10(8) cfu/bird on d 13) were studied in a 39-d experiment. a total of 1,216 male ross-308 chickens was assigned to 8 dietary treat ...200919096067
in vitro effects of alpha toxin from clostridium perfringens on the electrophysiological parameters of jejunal tissues from laying hens preincubated with inulin and n-acetyl-l-cysteine.the present report demonstrates the effect of alpha toxin from clostridium perfringens on electrophysiological indexes of jejunal mucosa from laying hens pretreated with inulin and n-acetyl-l-cysteine (acc), a mucolytic agent. in a first set of experiments, the effect of alpha toxin with or without pretreatment with acc on the electrophysiological parameters was determined when jejunal tissues from laying hens were mounted in ussing chambers. the short-circuit current remained unchanged when alp ...200919096074
enumeration of some cultivable bacterial groups and characterization of some abiotic variables in the jejunoileal content of prim'holstein veal calves.a study was conducted to characterize the bacterial and biochemical composition of the jejunoileal content of veal calves and the effect of pre-slaughter fasting time. at 22 wk of age, 22 preruminant prim'holstein calves fed milk replacer and pellets (mainly composed of corn) were slaughtered at 6, 12, or 24 h after their last meal. chyme samples were collected from the jejunoileal compartment just after slaughter, and ph and redox potential were immediately measured. culture-based methods were ...200919098252
portrait of an enzyme, a complete structural analysis of a multimodular {beta}-n-acetylglucosaminidase from clostridium perfringens.common features of the extracellular carbohydrate-active virulence factors involved in host-pathogen interactions are their large sizes and modular complexities. this has made them recalcitrant to structural analysis, and therefore our understanding of the significance of modularity in these important proteins is lagging. clostridium perfringens is a prevalent human pathogen that harbors a wide array of large, extracellular carbohydrate-active enzymes and is an excellent and relevant model syste ...200919193644
phylogenomic analyses of clostridia and identification of novel protein signatures that are specific to the genus clostridium sensu stricto (cluster i).the species of clostridium comprise a very heterogeneous assemblage of bacteria that do not form a phylogenetically coherent group. it has been proposed previously that only a subset of the species of clostridium that form a distinct cluster in the 16s rrna tree (cluster i) should be regarded as the true representatives of the genus clostridium (i.e. clostridium sensu stricto). however, this cluster is presently defined only in phylogenetic terms, and no biochemical, molecular or phenotypic char ...200919196767
intra-species growth-inhibition by clostridium perfringens is a possible virulence trait in necrotic enteritis in broilers.necrotic enteritis in broiler chickens is associated with clostridium perfringens type a, carrying the netb toxin. c. perfringens type a is also a member of the normal intestinal microbiota of broilers. clinically healthy chickens carry several different c. perfringens clones in their intestine. in flocks suffering from necrotic enteritis, however, mostly only one single clone is isolated from the gut of all the diseased animals. selective proliferation of these clinical outbreak strains in the ...200919201552
sporulation and enterotoxin (cpe) synthesis are controlled by the sporulation-specific sigma factors sige and sigk in clostridium perfringens.clostridium perfringens is the third most frequent cause of bacterial food poisoning annually in the united states. ingested c. perfringens vegetative cells sporulate in the intestinal tract and produce an enterotoxin (cpe) that is responsible for the symptoms of acute food poisoning. studies of bacillus subtilis have shown that gene expression during sporulation is compartmentalized, with different genes expressed in the mother cell and the forespore. the cell-specific rna polymerase sigma fact ...200919201796
establishment of an analytical system for the human fecal microbiota, based on reverse transcription-quantitative pcr targeting of multicopy rrna molecules.an analytical system based on rrna-targeted reverse transcription-quantitative pcr (rt-qpcr) was established for the precise evaluation of human intestinal microbiota. group- and species-specific primer sets for clostridium perfringens, lactobacillus spp. (six subgroups and three species), enterococcus spp., and staphylococcus spp. targeting 16s rrna gene sequences were newly developed for the quantitative analysis of such subdominant populations in human intestines. they were used together with ...200919201979
microbiological quality of ready-to-eat food served in schools in wales, united kingdom.a survey of the general microbiological quality of ready-to-eat food served in schools was undertaken across wales, united kingdom. of the 2,351 samples taken, four were identified as containing unsatisfactory counts of escherichia coli, four contained unsatisfactory counts of staphylococcus aureus, and one contained an unacceptable count of bacillus cereus when compared with guidelines for the microbiological quality of ready-to-eat food published by the united kingdom public health laboratory ...200919205487
clostridium perfringens beta-toxin targets endothelial cells in necrotizing enteritis in piglets.beta-toxin (cpb) is known to be the major virulence factor of clostridium perfringens type c strains, which cause necrotizing enteritis in pigs, sheep, goats, calves, and humans. the exact mode of action, in particular the cellular targets of cpb in the intestine of naturally affected species, is however still not resolved. to investigate localization of cpb in naturally occurring necrotizing enteritis, we evaluated 52 piglets with spontaneously acquired c. perfringens type c enteritis and 14 co ...200919216036
structural insight into the mechanism of streptozotocin inhibition of o-glcnacase.despite decades of its use in diabetes research, the mechanism of cytotoxicity of streptozotocin (stz) toward pancreatic beta-islet cells has remained a topic of discussion. although stz toxicity is likely a function of its capacity to promote dna alkylation, it has been proposed that stz induces pancreatic beta-cell death through o-glcnacase inhibition. in this report, we explore the binding mode of stz to a close homolog of human o-glcnacase, btgh84 from bacteroides thetaiotaomicron. our resul ...200919217614
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