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effect of apple intake on fecal microbiota and metabolites in humans.the effects of apple intake on the fecal flora, water content, ph, and metabolic activities in eight healthy volunteers and the utilization of apple pectin in vitro were investigated. although several isolates of bifidobacterium, lactobacillus, enterococcus, and the bacteroides fragilis group utilized apple pectin, most isolates of escherichia coli, collinsela aerofaciense, eubacterium limosum, and clostridium perfringens could not. when fecal samples from healthy adults were incubated in liquid ...201020304079
succession of the bacterial community and dynamics of hydrogen producers in a hydrogen-producing bioreactor.variation in the hydrogen production rate was consistent with the succession of dominant bacteria during the batch fermentation process. denaturing gradient gel electrophoresis (dgge) of 16s rrna genes and quantitative analysis of the hyda genes at both the dna and mrna levels confirmed that clostridium perfringens was the most dominant hydrogen producer in the bioreactor.201020305018
types of infectious outbreaks and their impact in elderly care facilities: a review of the literature.infectious outbreaks in long-term care facilities (ltcfs) tend to have a significant impact on infection rates and mortality rates of the residents.201020332371
in vitro production of necrotic enteritis toxin b, netb, by netb-positive and netb-negative clostridium perfringens originating from healthy and diseased broiler chickens.the clostridium perfringens necrotic enteritis toxin b, netb, was recently proposed as a new key virulence factor for the development of necrotic enteritis (ne) in broilers. the aim of the present study was to investigate the presence of the netb gene and the in vitro production of the netb toxin in a well characterized collection of 48 c. perfringens type a isolates, obtained from danish broiler flocks. the investigation revealed netb gene prevalences of approx. 50% and 60% among isolates from ...201020092968
a claudin-4 modulator enhances the mucosal absorption of a biologically active peptide.biologics, such as peptides, proteins and nucleic acids, are emerging pharmaceuticals. passage across the epithelium is the first step in the absorption of biologics. tight junctions (tj) function as seals between adjacent epithelial cells, preventing free movement of solutes across the epithelium. we previously found that modulation of a key tj component, claudin-4, is a potent method to enhance jejunal absorption when we used dextran as a model drug and the c-terminal fragment of clostridium p ...201020096266
desialylation of insulin receptors and igf-1 receptors by neuraminidase-1 controls the net proliferative response of l6 myoblasts to insulin.we recently established that the subunit of cell surface-residing elastin receptor, neuraminidase-1 (neu1), can desialylate adjacent insulin-like growth factor 1 receptors (igf-1r) of arterial smooth muscle cells, thereby quenching their proliferative response to insulin-like growth factor ii. in this study, we explored whether neu1 would also desialylate the insulin receptors (ir), as well as the igf-1r on rat skeletal l6 myoblasts, and whether desialylation of ir and igf-1r would affect a net ...201020100694
human enteric viruses in groundwater indicate offshore transport of human sewage to coral reefs of the upper florida keys.to address the issue of human sewage reaching corals along the main reef of the florida keys, samples were collected from surface water, groundwater and coral [surface mucopolysaccharide layers (sml)] along a 10 km transect near key largo, fl. samples were collected semi-annually between july 2003 and september 2005 and processed for faecal indicator bacteria (faecal coliform bacteria, enterococci and clostridium perfringens) and human-specific enteric viruses (enterovirus rna and adenovirus dna ...201020105219
release of glycoprotein (gp1) from the tegumental surface of taenia solium by phospholipase c from clostridium perfringens suggests a novel protein-anchor to membranes.in order to explore how molecules are linked to the membrane surface in larval taenia solium, whole cysticerci were incubated in the presence of phospholipase c from clostridium perfringens (plc). released material was collected and analyzed in polyacrylamide gels with sodium dodecyl sulfate. two major bands with apparent molecular weights of 180 and 43 kda were observed. western blot of released material and localization assays in cysticerci tissue sections using antibodies against five known s ...201020130782
presence of zoonotic pathogens in physico-chemically characterized manures from hog finishing houses using different production systems.hog production has been intensified in eastern canada, by 50% over the last 20years. wastes are now managed with conventional production systems (slatted floor), litter systems or source separation systems. we studied the presence of total and fecal coliforms, campylobacter, clostridium perfringens, enterococcus, escherichia coli, salmonella, yersinia enterocolitica, giardia and cryptosporidium in the manure of all of these production systems. the concentrations of the studied zoonotic pathogens ...201020133124
only two amino acids are essential for cytolytic toxin recognition of cholesterol at the membrane surface.the recognition and binding of cholesterol is an important feature of many eukaryotic, viral, and prokaryotic proteins, but the molecular details of such interactions are understood only for a few proteins. the pore-forming cholesterol-dependent cytolysins (cdcs) contribute to the pathogenic mechanisms of a large number of gram-positive bacteria. cholesterol dependence of the cdc mechanism is a hallmark of these toxins, yet the identity of the cdc cholesterol recognition motif has remained elusi ...201020145114
noncollagenous region of the streptococcal collagen-like protein is a trimerization domain that supports refolding of adjacent homologous and heterologous collagenous domains.proper folding of the (gly-xaa-yaa)(n) sequence of animal collagens requires adjacent n- or c-terminal noncollagenous trimerization domains which often contain coiled-coil or beta sheet structure. collagen-like proteins have been found recently in a number of bacteria, but little is known about their folding mechanism. the scl2 collagen-like protein from streptococcus pyogenes has an n-terminal globular domain, designated v(sp), adjacent to its triple-helix domain. the v(sp) domain is required f ...201020162611
induction of siv p27-specific multifunctional t cells in the gut following prime-boost immunization with clostridium perfringens and adenovirus vaccines expressing siv p27.a vaccine-induced cellular immune response to simian immunodeficiency virus (siv) in the gut mucosal tissue may prevent the establishment or severity of new siv infection. an oral clostridium perfringens expressing siv p27 (cp-p27) vaccine that delivers siv p27 to the gut was evaluated for its ability to prime multifunctional cellular immunity in the gut mucosa. gut peyer's patches dendritic cells matured in response to in vitro exposure to cp-p27 and stimulated production of p27-specific ifn-ga ...201020163344
comparative genomics of virr regulons in clostridium perfringens strains.clostridium perfringens is a gram-positive anaerobic bacterium causing severe diseases such as gas gangrene and pseudomembranosus colitis, that are generally due to the secretion of powerful extracellular toxins. the expression of toxin genes is mainly regulated by virr, the response regulator of a two-component system. up to now few targets only are known for this regulator and mainly in one strain (strain 13). due to the high genomic and phenotypic variability in toxin production by different ...201020184757
prebiotic effect of fruit and vegetable shots containing jerusalem artichoke inulin: a human intervention study.the present study aimed to determine the prebiotic effect of fruit and vegetable shots containing inulin derived from jerusalem artichoke (ja). a three-arm parallel, placebo-controlled, double-blind study was carried out with sixty-six healthy human volunteers (thirty-three men and thirty-three women, age range: 18-50 years). subjects were randomised into three groups (n 22) assigned to consume either the test shots, pear-carrot-sea buckthorn (pcs) or plum-pear-beetroot (ppb), containing ja inul ...201020187995
characterization of acp, a peptidoglycan hydrolase of clostridium perfringens with n-acetylglucosaminidase activity that is implicated in cell separation and stress-induced autolysis.this work reports the characterization of the first known peptidoglycan hydrolase (acp) produced mainly during vegetative growth of clostridium perfringens. acp has a modular structure with three domains: a signal peptide domain, an n-terminal domain with repeated sequences, and a c-terminal catalytic domain. the purified recombinant catalytic domain of acp displayed lytic activity on the cell walls of several gram-positive bacterial species. its hydrolytic specificity was established by analyzi ...201020190047
virulence for chickens of clostridium perfringens isolated from poultry and other sources.clostridium perfringens type a is the most common cause of poultry necrotic enteritis (ne). of the four "major" toxins, type a strains produce only alpha toxin (cpa), which has long been considered a major factor in pathogenesis of ne. we investigated the virulence for poultry of type a strains from a variety of enteric sources. newly-hatched cornishxrock chicks were fed a low protein diet for one week, a high protein diet for a second week, and then challenged with log-phase cultures of c. perf ...201020193771
detection of clostridium perfringens in yearling lamb meat (barbacoa), head, and gut tacos from public markets in mexico city.no reports on the incidence of clostridium perfringens in popularly-consumed food from mexico city have been published; neither are there any reports that have analyzed food consumed in popular markets and less established restaurants. therefore, this study is aimed at providing data to evaluate the relevance of c. perfringens as an etiologic agent of food-borne diseases. of the 650 analyzed samples, 106 (16.3%) were positive for c. perfringens; 6.4% (16/250) isolates were from barbacoa, 19% (38 ...201020198526
molecular cloning and expression of epsilon toxin from clostridium perfringens type d and tests of animal immunization.epsilon toxin produced by clostridium perfringens types b and d causes enterotoxemia in sheep, goats and calves. enterotoxemia can cause acute or superacute disease, with sudden death of the affected animal. it provokes huge economic losses when large numbers of livestock are affected. therapeutic intervention is challenging, because the disease progresses very rapidly. however, it can be prevented by immunization with specific immunogenic vaccines. we cloned the etx gene, encoding epsilon toxin ...201020198582
inhibition of clostridium perfringens spore germination and outgrowth by buffered vinegar and lemon juice concentrate during chilling of ground turkey roast containing minimal ingredients.inhibition of clostridium perfringens spore germination and outgrowth in ground turkey roast containing minimal ingredients (salt and sugar), by buffered vinegar (mostatin v) and a blend (buffered) of lemon juice concentrate and vinegar (mostatin lv) was evaluated. ground turkey roast was formulated to contain sea salt (1.5%), turbinado sugar (0.5%), and various concentrations of mostatin v (0.75, 1.25, or 2.5%) or mostatin lv (1.5, 2.5, or 3.5%), along with a control (without mostatins). the pr ...201020202331
claudin expression profiles in epstein-barr virus-associated nasopharyngeal carcinoma.claudins are a family of proteins that are structural and functional components of tight junctions and have crucial roles in the maintenance of cellular arrangement, adhesion and paracellular transport. recent studies have shown that changes and/or loss of claudin expression plays an important role in tumorigenesis and tumor progression, and altered expression of claudins has been reported in various human carcinomas. non-keratinizing nasopharyngeal carcinoma (npc) is a common epstein-barr virus ...201020204275
prevalence and diversity of toxigenic clostridium perfringens and clostridium difficile among swine herds in the midwest.clostridium perfringens and clostridium difficile are associated with scours in the neonatal piglet and are an economic concern in swine production. the objective of this study was to characterize the prevalence and diversity of c. perfringens and c. difficile isolates obtained from scouring neonatal piglets in a large integrated production system, as well as in smaller independently owned regional farms. rectal swabs were collected from 333 pigs at 11 sites in an integrated swine production sys ...201020208029
the cholesterol-dependent cytolysin family of gram-positive bacterial toxins.the cholesterol-dependent cytolysins (cdcs) are a family of beta-barrel pore-forming toxins secreted by gram-positive bacteria. these toxins are produced as water-soluble monomeric proteins that after binding to the target cell oligomerize on the membrane surface forming a ring-like pre-pore complex, and finally insert a large beta-barrel into the membrane (about 250 a in diameter). formation of such a large transmembrane structure requires multiple and coordinated conformational changes. the pr ...201020213558
cholesterol-binding toxins and anti-cholesterol antibodies as structural probes for cholesterol localization.cholesterol is one of the major constituents of mammalian cell membranes. it plays an indispensable role in regulating the structure and function of cell membranes and affects the pathology of various diseases. in recent decades much attention has been paid to the existence of membrane microdomains, generally termed lipid "rafts", and cholesterol, along with sphingolipids, is thought to play a critical role in raft structural organization and function. cholesterol-binding probes are likely to pr ...201020213560
hemolysis induced by bacillus cereus sphingomyelinase.bacillus cereus sphingomyelinase (bc-smase) induces hemolysis of sheep erythrocytes which contain large amounts of sphingomyelin. we investigated the mechanism of this hemolysis in comparison to that induced by clostridium perfringens alpha-toxin. pertussis toxin, a gi-specific inhibitor, n-oleoylethernolamine, a ceramidase inhibitor, and dihydrosphingosine, a sphingosine kinase inhibitor, did not inhibit the hemolysis by bc-smase, but did inhibit that by alpha-toxin. bc-smase broadly bound to w ...201020214877
transcriptional regulation of hemo encoding heme oxygenase in clostridium perfringens.a gram-positive anaerobic pathogen, clostridium perfringens, causes clostridial myonecrosis or gas gangrene in humans by producing numerous extracellular toxins and enzymes that act in concert to degrade host tissues. the ability of infectious bacteria to acquire sufficient iron during infection is essential for the pathogen to cause disease. in the c. perfringens strain 13 genome, a heme oxygenase gene homologue (cpe0214, hemo) was found and its role was examined. the purified recombinant hemo ...201020221736
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
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
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
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
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
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
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
massive intravascular haemolysis during clostridium perfrigens sepsis of hepatic origin. 201019682059
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
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
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
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
bug breakfast in the bulletin: gastroenteritis outbreaks in institutions. 201021426853
[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
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
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
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
[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
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
inactivation of indicators and pathogens in cattle feedlot manures and compost as determined by molecular and culture assays.accurate and conservative information about pathogen inactivation rates is needed as the basis for safe manure management on beef cattle feedlots. the survival of indicators and pathogens in faecal pen manure, stockpiled manure and manure compost was measured with autochthonous indicator bacteria (escherichia coli, clostridium perfringens, enterococci, total coliforms) and pathogens (listeria monocytogenes, campylobacter jejuni) using culture and/or real-time quantitative pcr (qpcr) methods. add ...201121446944
gut bacteria alteration in obese people and its relationship with gene polymorphism.to investigate the differences in cultivable gut bacteria and peroxisome proliferator-activated receptor ?2 (ppar-?2) gene pro12ala variation in obese and normal-weight chinese people.201121448362
the agr-like quorum-sensing system regulates sporulation and production of enterotoxin and beta2 toxin by clostridium perfringens type a non-food-borne human gastrointestinal disease strain f5603.clostridium perfringens type a strains producing enterotoxin (cpe) cause one of the most common bacterial food-borne illnesses, as well as many cases of non-food-borne human gastrointestinal disease. recent studies have shown that an agr-like quorum-sensing system controls production of chromosomally encoded alpha-toxin and perfringolysin o by c. perfringens, as well as sporulation by clostridium botulinum and clostridium sporogenes. the current study explored whether the agr-like quorum-sensing ...201121464088
effect of type of grinding of barley and dehydrated alfalfa on performance, digestion, and crude mucin ileal concentration in growing rabbits.the effect of type of grinding of barley and dehydrated alfalfa (da) was tested in rabbits weaned at 35 d of age with average bm of 846 ± 93 g. four non-medicated diets were arranged in a 2 x 2 factorial structure with type of grinding (coarse grinding with a 4.5-mm screen or fine grinding with a 1.5-mm screen) of barley (tgb) and da (tgda) as main factors. a total of 1,056 mixed-sex rabbits (264 per diet) were fattened until d 63. most of these rabbits (216 per diet) were housed in pairs and on ...201121478455
identification and characterization of a putative endolysin encoded by episomal phage phism101 of clostridium perfringens.clostridium perfringens produces potent toxins and histolytic enzymes, causing various diseases including life-threatening fulminant diseases in humans and other animals. aiming at utilizing a phage endolysin as a therapeutic alternative to antibiotics, we surveyed the genome and bacteriophage sequences of c. perfringens. a phism101 muramidase gene (psm) revealed by this study can be assumed to encode an n-acetylmuramidase, since the n-terminal catalytic domain deduced from the gene shows high h ...201121484204
bacterial enteritis in dogs and cats: diagnosis, therapy, and zoonotic potential.a variety of bacteria are known or suspected of being able to cause enteritis in dogs and cats. campylobacter spp, clostridium difficile, clostridium perfringens, and salmonella spp are most commonly implicated, but many other organisms are likely involved. poor understanding of the intestinal microflora and the fact that many, if not all, of these microorganisms can also be found in healthy individuals complicates testing, thereby affecting the use of specific treatments and assessment of poten ...201121486637
crystal structure of clostridium perfringens enterotoxin displays features of {beta}-pore-forming toxins.clostridium perfringens enterotoxin (cpe) is a cause of food poisoning and is considered a pore-forming toxin, which damages target cells by disrupting the selective permeability of the plasma membrane. however, the pore-forming mechanism and the structural characteristics of the pores are not well documented. here, we present the structure of cpe determined by x-ray crystallography at 2.0 å. the overall structure of cpe displays an elongated shape, composed of three distinct domains, i, ii, and ...201121489981
structure of an archaeal-type phosphoenolpyruvate carboxylase sensitive to inhibition by aspartate.the crystal structure of an archaeal-type phosphoenolpyruvate carboxylase from clostridium perfringens has been determined based on x-ray data extending to 3 å. the asymmetric unit of the structure includes two tetramers (each a dimer-of-dimers) of the enzyme. the precipitant, malonate, employed for the crystallization is itself a weak inhibitor of phosphoenolpyruvate carboxylase and a malonate molecule is seen in the active-site in the crystal structure. the allosteric binding sites for asparta ...201121491491
bacterial pathogens in hawaiian coastal streams-associations with fecal indicators, land cover, and water quality.this work aimed to understand the distribution of five bacterial pathogens in o'ahu coastal streams and relate their presence to microbial indicator concentrations, land cover of the surrounding watersheds, and physical-chemical measures of stream water quality. twenty-two streams were sampled four times (in december and march, before sunrise and at high noon) to capture seasonal and time of day variation. salmonella, campylobacter, staphylococcus aureus, vibrio vulnificus, and v. parahaemolytic ...201121492899
pathology of clostridium perfringens type c enterotoxemia in horses.clostridium perfringens type c is an important cause of enteritis and enterocolitis in foals and occasionally in adult horses. the disease is a classic enterotoxemia, and the enteric lesions and systemic effects are caused primarily by beta toxin, 1 of 2 major toxins produced by c. perfringens type c. until now, only sporadic cases of c. perfringens type c equine enterotoxemia have been reported. we present a comprehensive description of the lesions in 8 confirmed cases of type c enterotoxemia i ...201121502373
predictive model for growth of clostridium perfringens during cooling of cooked uncured meat and poultry.comparison of clostridium perfringens spore germination and outgrowth in cooked uncured products during cooling for different meat species is presented. cooked, uncured product was inoculated with c. perfringens spores and vacuum packaged. for the isothermal experiments, all samples were incubated in a water bath stabilized at selected temperatures between 10 and 51°c and sampled periodically. for dynamic experiments, the samples were cooled from 54.4 to 27°c and subsequently from 27 to 4°c for ...201121511140
design and synthesis of o-glcnacase inhibitors via 'click chemistry' and biological evaluations.protein o-glcnacylation has been shown to play an important role in a number of biological processes, including regulation of the cell cycle, dna transcription and translation, signal transduction, and protein degradation. o-glcnacase (oga) is responsible for the removal of o-linked β-n-acetylglucosamine (o-glcnac) from serine or threonine residues, and thus plays a key role in o-glcnac metabolism. potent oga inhibitors are useful tools for studying the cellular processes of o-glcnac, and may be ...201121514574
impact of beta-glucan on the faecal microbiota of polypectomized patients: a pilot study.beta-glucans are polysaccharides present in the cell walls of higher plants, in the seeds of some cereals, and certain yeasts and fungi also produce them. it is suggested that they exhibit, among many other health benefits, protective effects against carcinogenesis in the colon, but there is not enough human data to support this. the aim of the study was to determine the effect of barley-derived beta-glucan in the gut microbiota of polypectomized patients. subjects were randomly assigned to cons ...201121515398
chicken intestine microbiota following the administration of lupulone, a hop-based antimicrobial.the use of antibiotic growth promotants in poultry rearing is a public health concern due to antibiotic resistance in bacteria and the harborage of resistance genes. lupulone, a hop β-acid from humulus lupulus, has been considered as a potential feed additive growth promotant. here, the effect of lupulone was evaluated for its effect on the microbiota of the chicken intestine. the intestinal microbiota of broilers was quantified after the addition of 125 mg l(-1) lupulone to water and challenge ...201121517917
bacterial monocultures, propionate, butyrate and h(2) o(2) modulate the expression, secretion and structure of the fasting-induced adipose factor in gut epithelial cell lines.previous research showed that an intestinal microbial community represses the fasting-induced adipose factor (fiaf) in the gut epithelium, thereby increasing fat storage in the host. this study was designed to investigate the overall effect of different bacterial species and metabolites on fiaf in intestinal (caco-2, ht-29 and hct-116) and hepatic (hepg2) cancer cell lines. first, we showed that fiaf was present in different isoforms, and secreted as n-glycosylated proteins, exclusively at the b ...201121518214
molecular basis of toxicity of clostridium perfringens epsilon toxin.clostridium perfringensε-toxin is produced by toxinotypes b and d strains. the toxin is the aetiological agent of dysentery in newborn lambs but is also associated with enteritis and enterotoxaemia in goats, calves and foals. it is considered to be a potential biowarfare or bioterrorism agent by the us government centers for disease control and prevention. the relatively inactive 32.9 kda prototoxin is converted to active mature toxin by proteolytic cleavage, either by digestive proteases of the ...201121518257
real-time pcr analysis of enteric pathogens from fecal samples of irritable bowel syndrome subjects.abstract: background: growing amount of scientific evidence suggests that microbes are involved in the pathophysiology of irritable bowel syndrome (ibs). the predominant fecal microbiota composition of ibs subjects has been widely studied with dna-based techniques but less research has been focused on the intestinal pathogens in this disorder. here, we optimized a highly sensitive panel of 12 quantitative real-time pcr (qpcr) assays to shed light on the putative presence of intestinal pathogens ...201121518462
effects of genetically modified t2a-1 rice on faecal microflora of rats during 90 day supplementation.background: many animal studies have been performed on products with the bacillus thuringiensis insecticidal toxin-encoding gene (bt products), but less have focused on its effects on intestinal microflora owing to difficulties in culturing. this 90 day study was designed to assess unintended effects of genetically modified t2a-1 rice (gmr) on selected intestinal bacteria (lactobacillus group, bifidobacterium genus, escherichia coli subgroup, enterococcus genus and clostridium perfringens) of ra ...201121520451
characterization of the plasmidic or chromosomal cpe gene and metabolic activities in clostridium perfringens isolates from food in san luis--argentina.food poisoning and non-food poisoning illnesses due to c. perfringens (by enterotoxin production) have been associated to chromosomal or plasmidic location of the cpe gene, respectively. clostridial pathogenicity has been correlated to protease and azoreductase production. the aim of this work was: i) to assess the sanitary-hygienic quality of dehydrated soups (100 samples) consumed in san luis - argentina; ii) to verify the presence of c. perfringens in these food products using the "most proba ...201121526657
maternal sepsis due to clostridium perfringens after 2nd-trimester genetic amniocentesis. 201121534760
epsilon toxin: a fascinating pore-forming toxin.epsilon toxin (etx) is produced by strains of clostridium perfringens classified as type b or type d. etx belongs to the heptameric β-pore-forming toxins including aerolysin and clostridium septicum alpha toxin, which are characterized by the formation of a pore through the plasma membrane of eukaryotic cells consisting in a β-barrel of 14 amphipatic β strands. by contrast to aerolysin and c. septicum alpha toxin, etx is a much more potent toxin and is responsible for enterotoxemia in animals, m ...201121535407
analysis of caecal microbiota in rats fed with genetically modified rice by real-time quantitative pcr.the effect of genetically modified rice (gmr) on bacterial communities in caecal content was analyzed in a 90-d feeding rat model. a total of 12 groups of rats, which included male and female, were fed with the basal diets containing 30%, 50%, 70% gmr (b(1), b(2), b(3)) or 30%, 50%, 70% non-gmr (d(1), d(2), d(3)). the structure of intestinal microflora was estimated by real-time quantitative pcr (rq-pcr) based on genus-specific 16s rdna primers. sybr green was used for accurate detection and qua ...201121535699
enzyme molecular mechanism as a starting point to design new inhibitors: a theoretical study of o-glcnacase.o-glycoprotein 2-acetamino-2-deoxy-β-d-glucopyranosidase (o-glcnacase) hydrolyzes o-linked 2-acetamido-2-deoxy-β-d-glucopyranoside (o-glcnac) residues from post-translationally modified serine/threonine residues of nucleocytoplasmic protein. the chemical process involves substrate-assisted catalysis, where two aspartate residues have been identified as the two key catalytic residues of o-glcnacase. in this report, the first step of the catalytic mechanism used by o-glcnacase involving substrate- ...201121542586
assessment of levels of bacterial contamination of large wild game meat in europe.the variations in prevalence and levels of pathogens and fecal contamination indicators in large wild game meat were studied to assess their potential impact on consumers. this analysis was based on hazard analysis, data generation and statistical analysis. a total of 2919 meat samples from three species (red deer, roe deer, wild boar) were collected at french game meat traders' facilities using two sampling protocols. information was gathered on the types of meat cuts (forequarter or haunch; fi ...201121569954
application of broad-range resequencing array rpm-tei for detection of pathogens in desert dust samples from kuwait and iraq.a significant percentage of the human population is exposed to high levels of naturally occurring airborne dusts. although the link between airborne particulate inhalation and a variety of respiratory diseases has been long established, little is known about the pathogenic role of the microbial component of the dust. in this study, we applied highly multiplexed pcr and a high-density resequencing microarray (rpm-tei 1.0) to screen samples of fine topsoil particles and airborne dust collected in ...201121571877
effects of clostridium perfringens enterotoxin via claudin-4 on normal human pancreatic duct epithelial cells and cancer cells.the tight junction protein claudin-4 is frequently overexpressed in pancreatic cancer, and is also a receptor for clostridium perfringens enterotoxin (cpe). the cytotoxic effects of cpe are thought to be useful as a novel therapeutic tool for pancreatic cancer. however, the responses to cpe via claudin-4 remain unknown in normal human pancreatic duct epithelial (hpde) cells. we introduced the human telomerase reverse transcriptase (htert) gene into hpde cells in primary culture as a model of nor ...201121573709
investigation into drug release from colon-specific azoreductase-activated steroid prodrugs using in-vitro models.objectives  the aim of this study was to investigate drug release from a double steroid prodrug, opn501, which incorporates a phenylpropionate linker, and its phenylacetate analogue. the prodrugs, which were designed to deliver prednisolone to the colon for the treatment of inflammatory bowel disease, are based on a novel design that requires sequential azoreductase activity and cyclization of an amino ester to trigger drug release. we sought to explain the divergent effects of the two compounds ...201121585379
ruminococcin c, a new anti-clostridium perfringens bacteriocin produced in the gut by the commensal bacterium ruminococcus gnavus e1.when colonizing the digestive tract of mono-associated rats, ruminococcus gnavus e1 - a bacterium isolated from human faeces - produced a trypsin-dependent anti-clostridium perfringens substance collectively named ruminococcin c (rumc). rumc was isolated from the caecal contents of e1-monocontaminated rats and found to consist of two antimicrobial fractions: a single peptide (rumcsp) of 4235 da, and a mixture of two other peptides (rumcdp) with distinct molecular masses of 4324 da and 4456 da. b ...201121586310
the effect of lactobacillus fermentum on beta2 toxin production by clostridium perfringens.clostridium perfringens although a member of the normal gut flora is also an important cause of intestinal disease in animals and, to a lesser extent, in humans. disease is associated with the production of one or more toxins and little is known about environmental influences on the production of these toxins. one of the health promoting effects of lactic acid bacteria (lab) is the establishment and maintenance of a low ph in the intestine since an acidic environment inhibits the growth of many ...201121602389
determination of toxinotypes of environmental clostridium perfringens by polymerase chain reaction.toxinotype of clostridium perfringens (cp) isolates collected from the bernam river, selangor river and tengi canal between april 2007 and january 2008 were determined by polymerase chain reaction (pcr) using published primers. all the 147 isolates were toxinotype type a, harbouring the alpha toxin gene. in addition, 5 of the isolates also had the enterotoxin (cpe) gene.201121602783
a unique endo-β-galactosidase that cleaves both blood group a and b glycotopes. 201121618105
influence of dietary supplementation with bacillus-fermented adlay on lipid metabolism, antioxidant status and intestinal microflora in hamsters.background: the effects of polished and dehulled bacillus-fermented adlay on lipid metabolism, antioxidant status and intestinal microflora were examined in hyperlipidaemic hamsters fed a high-cholesterol diet. results: hamsters administered bacillus-fermented adlay experienced significantly reduced (p < 0.05) serum and hepatic total cholesterol (by 37-43% and 42-49% respectively) and triglyceride (by 22-27% and 30-35% respectively) levels compared with the high-cholesterol group. lower low-dens ...201121618546
isolation of microbial pathogens of subclinical mastitis from raw sheep's milk of epirus (greece) and their role in its hygiene.the natural raw milk microflora is a factor that expresses its sensorial characteristics. the microbial charge into the mammary gland of healthy animal is low and the application of right and healthy conditions during milking and cheese making procedure, prevents from contaminating as well as maintains the natural microflora in order to lend the particular characteristics of milk. the purpose of the present project was the study of the total viable count (t.v.c.) and the count of total psychrotr ...201121620987
occurrence of clostridium perfringens from different cultivated soils.the occurrence of clostridium perfringens was estimated in 750 samples originated from a variety of soils bearing various bulb crops: brawnica oderacea (vegetable), olea europaea, daucus carota (carote), solanum tuberosum (potato), phaseolus vulgaris (green haricot), beta vulgaris var. rapaceum (beetroot), cucurbita pepo (squash), allium cepa (onion), cucumis sativus (cucumber) and capsicum annum (pepper). all isolated strains were tested for their antimicrobial activities to amoxicillin, penici ...201121621626
a mild outbreak of gastroenteritis in long-term care facility residents due to clostridium perfringens, australia 2009.clostridium perfringens food poisoning is a commonly cited cause of gastroenteritis outbreaks among elderly long-term care facility (ltcf) residents, yet little is known about the natural history of disease in this vulnerable group. in july 2009, an investigation into diarrheal illness among ltcf residents was commenced.201121381919
analysis of a new family of widely distributed metal-independent alpha-mannosidases provides unique insight into the processing of n-linked glycans.the modification of n-glycans by +¦-mannosidases is a process that is relevant to a large number of biologically important processes, including infection by microbial pathogens and colonization by microbial symbionts. at present, the described mannosidases specific for +¦1,6-mannose linkages are very limited in number. through structural and functional analysis of two sequence-related enzymes, one from streptococcus pneumoniae (spgh125) and one from clostridium perfringens (cpgh125), a new glyco ...201121388958
crystallization and preliminary x-ray diffraction studies of delta-toxin from clostridium perfringens.clostridium perfringens is a gram-positive anaerobic bacterium that is responsible for a wide range of diseases in humans and both wild and domesticated animals, including birds. c. perfringens is notable for its ability to produce a plethora of toxins, e.g. phospholipases c (alpha-toxin), pore-forming toxins (epsilon-toxin, beta-toxin and enterotoxin) and binary toxins (iota-toxin). based on alpha-, beta-, epsilon- and iota-toxin production, the bacterium is classified into five different toxin ...201121393845
necrotic enteritis in young calves.non-enterotoxin (cpe)-producing clostridium perfringens type a has been associated with enteritis in calves. recent evidence has suggested that a novel toxin, named beta2 (cpb2), is implicated in the pathogenesis of this disease, although there is little evidence supporting this. in the current study, the role of c. perfringens type a in an outbreak of enteritis in calves was studied. two 20-day-old dairy calves exhibiting apathy and reluctance to eat, with paresis of the anterior limbs, were eu ...201121398444
beta 2 toxigenic clostridium perfringens type a colitis in a three-day-old foal.beta 2 (+¦2)-toxigenic clostridium perfringens type a was recovered in large numbers from the intestine of a neonatal foal with colitis. the foal had been treated with gentamicin. necropsy revealed marked distension of cecum and colon with watery, rust-colored homogeneous fluid and gastric infarction. microscopic colonic lesions were superficial necrosis of 50% of the colonic mucosal surface and scattered 1-3-mm ulcers with subjacent neutrophilic infiltration and large gram-positive bacilli in t ...201121398467
regulation of virulence by the revr response regulator in clostridium perfringens.clostridium perfringens causes clostridial myonecrosis or gas gangrene and produces several extracellular hydrolytic enzymes and toxins, many of which are regulated by the virsr signal transduction system. the revr gene encodes a putative orphan response regulator that has similarity to the yycf (walr), vicr, phob, and phop proteins from other gram-positive bacteria. revr appears to be a classical response regulator, with an n-terminal receiver domain and a c-terminal domain with a putative wing ...201121402758
susceptibility of primary human endothelial cells to c. perfringens beta-toxin suggesting similar pathogenesis in human and porcine necrotizing enteritis.clostridium perfringens type c causes fatal necrotizing enteritis in different mammalian hosts, most commonly in newborn piglets. human cases are rare, but the disease, also called pigbel, was endemic in the highlands of papua new guinea. lesions in piglets and humans are very similar and characterized by segmental necro-hemorrhagic enteritis in acute cases and fibrino-necrotizing enteritis in subacute cases. histologically, deep mucosal necrosis accompanied by vascular thrombosis and necrosis w ...201121411248
gene-trap mutagenesis identifies mammalian genes contributing to intoxication by clostridium perfringens e-toxin.the clostridium perfringens e-toxin is an extremely potent toxin associated with lethal toxemias in domesticated ruminants and may be toxic to humans. intoxication results in fluid accumulation in various tissues, most notably in the brain and kidneys. previous studies suggest that the toxin is a pore-forming toxin, leading to dysregulated ion homeostasis and ultimately cell death. however, mammalian host factors that likely contribute to e-toxin-induced cytotoxicity are poorly understood. a lib ...201121412435
antibacterial activity of the enniatin b, produced by fusarium tricinctum in liquid culture, and cytotoxic effects on caco-2 cells.the enniatins (ens) are bioactive compounds of hexadepsipeptidic structure produced by several strains of fusarium sp. the en b was purified from extracts of fusarium tricinctum growth on liquid culture of potato dextrose broth (pdb), using a semipreparative liquid chromatography (lc) followed by an analytical lc. the purity and the structure of the isolated compound were confirmed by the determination of the extinction coefficient and with electrospray ionization-mass spectrometry (esi-ms) stud ...201121417626
recent progress in understanding the pathogenesis of clostridium perfringens type c infections.clostridium perfringens type c causes necrotizing enteritis in humans and several other animal species. type c isolates must produce at least beta toxin (cpb) and alpha toxin (cpa) and most strains produce several other toxins including perfringolysin o (pfo) and tpel. however, current evidence indicates that cpb is the main virulence factor for type c infections. most of this evidence is based upon the loss of virulence shown by isogenic type c cpb knock out mutants on cells, and also in rabbit ...201121420802
microbial ecology of fish species ongrowing in greek sea farms and their watery environment.the present study focuses on the bacteriological profile of both watery ecosystem and fishes from different north and central west greek fish-farms ongrowing euryhaline fish species. the natural microflora of the fish and the water of their ongrowing units in selected farms were studied for a period of 20 months. the analyzed samples were mainly sea bream (sparus aurata) 61.3% and sea bass (dicentrarchus labrax) 24%. in most of the watery ecosystems coming from the different sampling areas, tota ...201121421068
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