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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
microbiological analysis of stuffed mussels sold in the streets.stuffed mussel is a traditional food that sold by street venders in various countries. in the present study, samples of stuffed mussels were collected from various places in ankara. the mussels were analyzed to show the microbiological risks for human health. thirty samples (600 stuffed mussels in total) were collected periodically and microbiological analyses were performed by standard procedures for bacillus cereus, staphylococcus aureus, escherichia coli, salmonella sp., clostridium sp. in te ...201122754015
expression and characterization of an endo-1,4-β-galactanase from emericella nidulans in pichia pastoris for enzymatic design of potentially prebiotic oligosaccharides from potato galactans.potato pulp is a high-volume side-stream from industrial potato starch manufacturing. enzymatically solubilized β-1,4-galactan-rich potato pulp polysaccharides of molecular weights >100 kda (sppp) are highly bifidogenic in human fecal sample fermentations in vitro. the objective of the present study was to use potato β-1,4-galactan and the sppp as substrates for enzymatic production of potentially prebiotic compounds of lower and narrower molecular weight. a novel endo-1,4-β-galactanase from eme ...201122226198
use of essential oils and extracts from spices in meat protection.the hydro distillation method was used in this study to get essential oils (eos) from cumin (cuminum cyminum l.), clove (eugenia caryohyllata) and elecampane (inula helenium l.) and the co-hydro distillation method (addition of fatty acid ethyl esters as extraction cosolvents) to get functional extracts (efs). the mic (minimum inhibitory concentration) and the mbc (minimum bactericidal concentration) were determined on five pathogenic strains (escherichia coli o157:h7, salmonella, listeria monoc ...201124803704
validation of a numerical indicator of microbial contamination for karst springs.rapid changes in spring water quality in karst areas due to rapid recharge of bacterially contaminated water are a major concern for drinking water suppliers and users. the main objective of this study was to use field experiments with fecal indicators to verify the vulnerability of a karst spring to pathogens, as determined by using a numerical modeling approach. the groundwater modeling was based on linear storage models that can be used to simulate karst water flow. the vulnerability of the k ...201120180864
clostridium perfringens epsilon toxin is cytotoxic for human renal tubular epithelial cells.clostridium perfringens epsilon toxin (etx) is responsible for a fatal enterotoxemia in different animal species, producing extensive renal damage, neurological disturbance and edema of lungs, heart and kidneys. however, there is no information about the susceptibility of humans to etx. here, we report that primary cultures of human renal tubular epithelial cells (hrtec) exposed to etx showed a marked swelling with subsequent large blebs surrounding most cells. the incubation of hrtec with etx p ...201120488848
clostridium perfringens sepsis and fetal demise after genetic amniocentesis.clostridium perfringens is a rare cause of intrauterine infection. there have been five case reports concerning infection associated with invasive procedures. we report a woman who underwent a genetic amniocentesis due to her history of chronic granulomatous disease. she presented to the hospital ∼38 hours after the amniocentesis complaining of fever and chills. due to acute decompensation, she underwent an emergent dilatation and evacuation. during her stay, blood cultures came back positive fo ...201123705080
fulminating septic shock from clostridium perfringens in an early breast cancer patient with severe myalgia after docetaxel treatment.anaerobic bacteraemia could be a life-threatening condition in neutropenic patients receiving chemotherapy. taxane therapy is associated with necrotising inflammation of the caecum (named also typhlitis) that could be a potential source for bacteraemia. we report the case of a sudden onset of septic shock by clostridium perfringens in a young patient treated with docetaxel as adjuvant chemotherapy for early breast cancer. a mini-review of the literature has been performed.201124765295
quality of water sources used as drinking water in a brazilian peri-urban area.the objective of this paper was to assess bacteriological quality of drinking water in a peri-urban area located in the metropolitan region of são paulo, brazil. a total of 89 water samples were collected from community plastic tanks and 177 water samples from wells were collected bimonthly, from september 2007 to november 2008, for evaluating bacteriological parameters including: escherichia coli, enterococcus and heterotrophic plate count (hpc). clostridium perfringens was investigated in a su ...201124031668
gas gangrene as a result of femoral traction pin placement.treatment of adult femoral shaft fractures typically involves operative stabilization with intramedullary implants, external fixation, or a plate and screw construct. however, when stabilization is delayed for any reason, use of a traction pin is recommended to stabilize the fracture, prevent significant shortening, as well as to help with pain control. in this paper, we present the rare complication of a severe gas gangrene infection caused by clostridium perfringens that led to several amputat ...201123198212
severe clostridial pyomyoma following an abortion does not always require surgical intervention.background. clostridial infection following pregnancy may be fatal, and surgery is considered as the treatment of choice. we suggest a conservative management in selected cases when preservation of fertility is of major importance. case. a 41-year-old primigravida presented with abdominal pain and fever, one day following dilatation and curettage at 20 weeks of gestation. her abdomen was diffusely tender, with a uterus enlarged to 20 weeks' gestation. laboratory studies were consistent with seps ...201122567505
impact of fresh or used litter on the posthatch immune system of commercial broilers.this study was carried out to investigate the effects of exposure of growing broiler chickens of commercial origin to used poultry litter on intestinal and systemic immune responses. the litter types evaluated were fresh wood shavings or used litter obtained from commercial poultry farms with or without a history of gangrenous dermatitis (gd). immune parameters measured were serum nitric oxide (no) levels, serum antibody titers against eimeria or clostridium perfringens, mitogen-induced spleen c ...201122312971
responses of feeding prebiotics on nutrient digestibility, faecal microbiota composition and short-chain fatty acid concentrations in dogs: a meta-analysis.the effects of prebiotics on digestibility, short-chain fatty acid (scfa) concentrations and bacterial populations in the faeces and immunity in dogs were evaluated by meta-analyses. overall, data from 15 published studies containing 65 different treatment means of 418 observations from different breeds of dogs were included in the data set. feeding of prebiotics to dogs did not affect the nutrient intake (p > 0.10), nor did prebiotics change (p > 0.10) the digestibility of dry matter (dm) and f ...201122440414
effect of temperature on microbial growth rate-mathematical analysis: the arrhenius and eyring-polanyi connections.the objective of this work is to develop a mathematical model for evaluating the effect of temperature on the rate of microbial growth. the new mathematical model is derived by combination and modification of the arrhenius equation and the eyring-polanyi transition theory. the new model, suitable for both suboptimal and the entire growth temperature ranges, was validated using a collection of 23 selected temperature-growth rate curves belonging to 5 groups of microorganisms, including pseudomona ...201122417589
claudin and ovarian cancer.claudins are a family of proteins and the most important component of the tight junction. they constitute a paracellular barrier that controls the flow of molecules in the intercellular space of an epithelium. although it seems that claudin should be down regulated in cancer cell, some claudins are, in fact highly elevated in various human cancers, including ovarian cancer. whereas the functional significance of claudin overexpression in ovarian carcinoma is unclear, these proteins are important ...201024591894
clostridium perfringens toxins involved in mammalian veterinary diseases.clostridium perfringens is a gram-positive anaerobic rod that is classified into 5 toxinotypes (a, b, c, d, and e) according to the production of 4 major toxins, namely alpha (cpa), beta (cpb), epsilon (etx) and iota (itx). however, this microorganism can produce up to 16 toxins in various combinations, including lethal toxins such as perfringolysin o (pfo), enterotoxin (cpe), and beta2 toxin (cpb2). most diseases caused by this microorganism are mediated by one or more of these toxins. the role ...201024511335
dietary cellulose, fructooligosaccharides, and pectin modify fecal protein catabolites and microbial populations in adult cats.twelve young adult (1.7 +/- 0.1 yr) male cats were used in a replicated 3 x 3 latin square design to determine the effects of fiber type on nutrient digestibility, fermentative end products, and fecal microbial populations. three diets containing 4% cellulose, fructooligosaccharides (fos), or pectin were evaluated. feces were scored based on the 5-point system: 1 being hard, dry pellets, and 5 being watery liquid that can be poured. no differences were observed (p > 0.100) in intake of dm, om, c ...201020495116
pilot study on the efficacy of paromomycin as a histomonostatic feed additive in turkey poults experimentally infected with histomonas meleagridis.paromomycin is an aminoglycoside antibiotic with activity against protozoa. currently, paromomycin is registered for food producing animal species. in a pilot study we evaluated the efficacy of different doses of paromomycin in the feed against histomonas meleagridis in experimentally challenged turkey poults. groups consisting of 30 birds each were given feed with 100, 200 and 400 ppm paromomycin, respectively, starting on day 1 through to day 42. one group of 30 birds was left untreated. on da ...201020496863
comparison of alternatives to in-feed antimicrobials for the prevention of clinical necrotic enteritis.the capacity for lactobacillus johnsonii and an organic acid (oa) blend to prevent clostridium perfringens-induced clinical necrotic enteritis (ne) in chickens was studied.201020497278
effect of phosphate and meat (pork) types on the germination and outgrowth of clostridium perfringens spores during abusive chilling.the effect of phosphate blends and pork meat type (pale, soft, and exudative [pse]; normal; and dark, firm, and dry [dfd]) on the germination and outgrowth of clostridium perfringens during abusive exponential chilling times was evaluated. two phosphates were used: tetrasodium pyrophosphate (tspp) and sodium acid pyrophosphate (sapp; from two different sources, sapp(1) and sapp(2)). the pork loins representing each meat type were ground (1/8-in. [0.3-cm] plate), and one of the three phosphate bl ...201020501039
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
effect of tannins on the in vitro growth of clostridium perfringens.vegetable tannins are water-soluble polyphenolic compounds of varying molecular weights that occur abundantly in nature. the diet of many free-ranging wild animals contains significant amounts of tannins. also, commercial tannins are used in animal industry as food additives to improve animal performance. in order to further determine the capacity of tannins to inhibit the development of intestinal diseases produced by clostridium pefringens, we evaluated here the effect of tannins from quebrach ...201020471759
web of ecological interactions in an experimental gut microbiota.the dynamics of all ecosystems are dictated by intrinsic, density-dependent mechanisms and by density-independent environmental forcing. in spite of the importance of the gastrointestinal microbiota in health and disease, the ecology of this system remains largely unknown. here, we take an ecological approach to gut microbial community analysis, with statistical modelling of time series data from chemostats. this approach removes effects of host forcing, allowing us to describe a network of intr ...201020482738
development of a recombinant epsilon toxoid vaccine against enterotoxemia and its use as a combination vaccine with live attenuated sheep pox virus against enterotoxemia and sheep pox.sheep pox and enterotoxemia are important diseases of sheep, and these diseases cause severe economic losses to sheep farmers. the present study was undertaken to evaluate the potential of formaldehyde-inactivated recombinant epsilon toxin as a vaccine candidate. the potency of the recombinant epsilon toxoid with aluminum hydroxide as an adjuvant in sheep was determined. vaccinated sheep were protected against enterotoxemia, with potency values of >5 iu being protective. further, the use of this ...201020427629
quantum mechanical/molecular mechanical molecular dynamics simulation of wild-type and seven mutants of cpnagj in complex with pugnac.the enzyme o-glycoprotein 2-acetamino-2-deoxy-beta-d-glucopyranosidase (o-glcnacase) is responsible for the removal of n-acetylglucosamine moieties from 2-acetamido-2-deoxy-beta-d-glucopyranose (o-glcnac) residues of serine/threonine residues of modified proteins. we herein present results of hybrid quantum mechanics/molecular mechanics (qm/mm) molecular dynamics (md) simulations applied to the study of the interactions established between a bacterial clostridium perfringens homologue (cpnagj) a ...201020429600
isolation of a clonal population of clostridium perfringens type a from a belgian blue calf with abomasal ulceration.a case of abomasal ulceration in a 3-month-old belgian blue calf is described. microscopical examination revealed the ulcers to be demarcated by a band of neutrophilic inflammation that separated underlying healthy tissue from the superficial fibrinous necrotic material in which bacteria were present. clostridium perfringens type a was isolated from multiple ulcers and from the intestinal contents of the animal and pulsed field gel electrophoresis confirmed that the isolates comprised a genetica ...201020430403
clostridium perfringens epsilon toxin inhibits the gastrointestinal transit in mice.epsilon toxin produced by clostridium perfringens type b and d is a potent toxin that is responsible for a highly fatal enterotoxemia in sheep and goats. in vitro, epsilon toxin produces contraction of the rat ileum as the result of an indirect action, presumably mediated through the autonomic nervous system. to examine the impact of epsilon toxin in the intestinal transit, gastric emptying (ge) and gastrointestinal transit (git) were evaluated after intravenous and oral administration of epsilo ...201020434186
clostridium perfringens and necrotizing enterocolitis. 201020434729
a claudin-targeting molecule as an inhibitor of tumor metastasis.tumor metastasis of epithelium-derived tumors is the major cause of death from malignant tumors. overexpression of claudin is observed frequently in malignant tumors. however, claudin-targeting antimetastasis therapy has never been investigated. we previously prepared a claudin-4-targeting antitumor molecule that consisted of the c-terminal fragment of clostridium perfringens enterotoxin (c-cpe) fused to protein synthesis inhibitory factor (psif) derived from pseudomonas exotoxin. in the present ...201020442222
regulation of neurotoxin production and sporulation by a putative agrbd signaling system in proteolytic clostridium botulinum.a significant number of genome sequences of clostridium botulinum and related species have now been determined. in silico analysis of these data revealed the presence of two distinct agr loci (agr-1 and agr-2) in all group i strains, each encoding putative proteins with similarity to agrb and agrd of the well-studied staphylococcus aureus agr quorum sensing system. in s. aureus, a small diffusible autoinducing peptide is generated from agrd in a membrane-located processing event that requires ag ...201020453132
the virsr two-component signal transduction system regulates netb toxin production in clostridium perfringens.clostridium perfringens causes several diseases in domestic livestock, including necrotic enteritis in chickens, which is of concern to the poultry industry due to its health implications and associated economic cost. the novel pore-forming toxin netb is a critical virulence factor in the pathogenesis of this disease. in this study, we have examined the regulation of netb toxin production. in c. perfringens, the quorum sensing-dependent virsr two-component signal transduction system regulates ge ...201020457789
in vitro antagonistic activities of animal intestinal strains against swine-associated pathogens.a wide range of enteropathogens cause costly diarrhoeal diseases in fattening piglets and account for food-related infections in humans. the objective of this study was to screen beneficial bacterial strains from the gastrointestinal tract of various animal sources for antagonistic activity against diverse pathogens associated with hazardous pig production times. using agar spot assays, 15 well-characterized strains belonging to lactobacillus, enterococcus, bifidobacterium and bacillus were stud ...201020226602
claudin-4-targeting of diphtheria toxin fragment a using a c-terminal fragment of clostridium perfringens enterotoxin.claudin (cl)-4, a tight junction protein, is overexpressed in some human neoplasias, including ovarian, breast, pancreatic and prostate cancers. the targeting of cl-4 is a novel strategy for tumor therapy. we previously found that the c-terminal fragment of clostridium perfringens enterotoxin (c-cpe) binds to cl-4. in the present study, we genetically prepared a novel cl-4-targeting molecule (dta-c-cpe) by fusion of c-cpe and diphtheria toxin fragment a (dta). although dta is not toxic to cl-4-e ...201020226859
removal of human enteric viruses and indicator microorganisms from domestic wastewater by aerated lagoons.aerated lagoons offer a low-cost and simple approach to treating domestic wastewater in small municipalities. the objective of the current study was to evaluate, for each cell in the lagoons, the removal of indicator microorganisms and human enteric viruses under warm (summer) and cold (early spring) conditions. the two sites are located in southwest quebec, canada. samples were assayed for thermotolerant coliforms, enterococci, clostridium perfringens, somatic and male-specific coliphages, and ...201020237581
uva-induced cyclobutane pyrimidine dimers in dna: a direct photochemical mechanism?the carcinogenic action of uva radiation is commonly attributed to dna oxidation mediated by endogenous photosensitisers. yet, it was recently shown that cyclobutane pyrimidine dimers (cpd), well known for their involvement in uvb genotoxicity, are produced in larger yield than oxidative lesions in uva-irradiated cells and skin. in the present work, we gathered mechanistic information on this photoreaction by comparing formation of all possible bipyrimidine photoproducts upon uva irradiation of ...201020237685
crystal structures of the cbs and drtgg domains of the regulatory region of clostridiumperfringens pyrophosphatase complexed with the inhibitor, amp, and activator, diadenosine tetraphosphate.nucleotide-binding cystathionine beta-synthase (cbs) domains serve as regulatory units in numerous proteins distributed in all kingdoms of life. however, the underlying regulatory mechanisms remain to be established. recently, we described a subfamily of cbs domain-containing pyrophosphatases (ppases) within family ii ppases. here, we express a novel cbs-ppase from clostridium perfringens (cpe2055) and show that the enzyme is inhibited by amp and activated by a novel effector, diadenosine 5',5-p ...201020303981
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
prenylated pterocarpans as bacterial neuraminidase inhibitors.during the course of a neuraminidase inhibitor screening program on natural products, four new (6, 8, 11, and 12) and eleven known (1-5, 7, 9-10, and 13-15) pterocarpan derivatives were isolated as active principles from the etoac extract of the stem bark of erythrina abyssinica. their structures were identified by spectroscopic data analyses. all isolates exhibited significant inhibitory effects on the neuraminidases from clostridium perfringens and vibrio cholerae with ic(50) values ranging fr ...201020363636
antibacterial effect of the bioactive compound beauvericin produced by fusarium proliferatum on solid medium of wheat.to obtain the bioactive compound beauvericin (bea), fusarium proliferatum cect 20569 was grown on a solid medium of wheat, utilizing the technique of the solid state fermentation (ssf), being this mycotoxin purified by high performance liquid chromatography (hplc) with a reverse phase semi-preparative column using as the mobile phase acetonitrile/water in gradient condition. the purity of the bea was verified by analytical hplc and liquid chromatography tandem mass spectrometry (lc/ms-ms). the p ...201020371252
sorbitol-fermenting bifidobacteria are indicators of very recent human faecal pollution in streams and groundwater habitats in urban tropical lowlands.sorbitol-fermenting bifidobacteria (sfb) proved to be an excellent indicator of very recent human faecal pollution (hours to days) in the investigated tropical stream and groundwater habitats. sfb were recovered from human faeces and sources potentially contaminated with human excreta. sfb were undetectable in animal faeces and environmental samples not contaminated with human faeces. microcosm studies demonstrated a rapid die-off rate in groundwater (t90 value 0.6 days) and stream water (t90 va ...201020375476
fibronectin-binding proteins of clostridium perfringens recognize the iii1-c fragment of fibronectin.the clostridium perfringens strain 13 genome contains two genes (fbpa, fbpb) that encode putative fbp. both rfbpa and rfbpb were purified and their reactivity with human serum fn was analyzed. to determine the region of the fn molecule recognized by rfbp, a plate binding assay using n-terminal 70-kda peptide, iii1-c peptide, and 110-kda peptide containing iii2-10 of fn was performed. both rfbp bound to the iii1-c peptide of fn but not to the other peptides. however, the iii1-c fragment of fn is ...201020377750
enzootic outbreak of necrotic gastritis associated with clostridium perfringens in broiler chickens.clinical morphological investigations were carried out in a flock of 22,000 ross 308 broiler chickens at the age of 38 days that experienced a sudden increase in mortality rates. morbidity and mortality rates were followed and gross anatomical examination of 150 bodies (7%) of all 1541 dead chickens was performed. in all necropsied birds, without exception, the typical macroscopic lesions were observed only in the gizzard. focal or diffuse pseudomembranous deposits were found subcuticularly and ...201020390530
exogenous lysozyme influences clostridium perfringens colonization and intestinal barrier function in broiler chickens.necrotic enteritis is a worldwide poultry disease caused by the overgrowth of clostridium perfringens in the small intestine. an experiment with a 2x2 factorial design (supplementation with or without 40 mg lysozyme/kg diet for chickens challenged with or without c. perfringens) was conducted to investigate the inhibitory efficacy of exogenous lysozyme against intestinal colonization by c. perfringens in chickens subject to oral inoculation of c. perfringens type a on days 17 to 20. the c. perfr ...201020390532
the effect of commonly used anticoccidials and antibiotics in a subclinical necrotic enteritis model.necrotic enteritis poses an important health risk to broilers. the ionophore anticoccidials lasalocid, salinomycin, maduramicin, narasin and a combination of narasin and nicarbazin were tested in feed for their prophylactic effect on the incidence of necrotic enteritis in a subclinical experimental infection model that uses coccidia as a predisposing factor. in addition, drinking water medication with the antibiotics amoxicillin, tylosin and lincomycin was evaluated as curative treatment in the ...201020390538
control of clostridium perfringens-induced necrotic enteritis in broilers by target-released butyric acid, fatty acids and essential oils.the efficacy of target-released butyric acid, medium-chain fatty acids (c(6) to c(12) but mainly lauric acid) and essential oils (thymol, cinnamaldehyde, essential oil of eucalyptus) micro-encapsulated in a poly-sugar matrix to control necrotic enteritis was investigated. the minimal inhibitory concentrations of the different additives were determined in vitro, showing that lauric acid, thymol, and cinnamaldehyde are very effective in inhibiting the growth of clostridium perfringens. the in vivo ...201020390546
toxin genotyping of clostridium perfringens strains using a polymerase chain reaction protocol.a polymerase chain reaction protocol consisting of a multiplex to identify the cpa, cpb1, cpetx, cpi genes and a duplex to identify the cpe and cpb2 genes encoding for alpha, beta1, epsilon, eta, enterotoxin and beta2 toxins, respectively, was applied to dna extracted from two collections of clostridium perfringens strains. the first collection involved 19 isolates from rabbits. the second collection of 41 isolates came from routine necropsies. the cpa gene alone, or in association with the cpb2 ...201020391372
mucosal vaccination using claudin-4-targeting.mucosa-associated lymphoid tissue (malt) plays pivotal roles in mucosal immune responses. efficient delivery of antigens to malt is a critical issue for the development of mucosal vaccines. although claudin-4 is preferentially expressed in malt in the gut, a claudin-4-targeting approach for mucosal vaccination has never been developed. in the present study, we found that claudin-4 is expressed in nasal malt, and we prepared a fusion protein of ovalbumin (ova) as a model antigen with a claudin-4- ...201020398936
quantitative real-time pcr assay for clostridium septicum in poultry gangrenous dermatitis associated samples.clostridium septicum is a spore-forming anaerobe frequently implicated in cases of gangrenous dermatitis (gd) and other spontaneously occurring myonecrotic infections of poultry. although c. septicum is readily cultured from diseased tissues it can be difficult to enumerate due to its tendency to swarm over the surface of agar plates. in this study a quantitative real-time pcr assay was developed in order to more accurately measure the levels of c. septicum in healthy as well as gd associated po ...201020399850
rapid cytopathic effects of clostridium perfringens beta-toxin on porcine endothelial cells.clostridium perfringens type c isolates cause fatal, segmental necro-hemorrhagic enteritis in animals and humans. typically, acute intestinal lesions result from extensive mucosal necrosis and hemorrhage in the proximal jejunum. these lesions are frequently accompanied by microvascular thrombosis in affected intestinal segments. in previous studies we demonstrated that there is endothelial localization of c. perfringens type c beta-toxin (cpb) in acute lesions of necrotizing enteritis. this led ...201020404076
bacteriophage therapy for control of necrotic enteritis of broiler chickens experimentally infected with clostridium perfringens.several lytic bacteriophages effective at destroying a genetically diverse population of clostridium perfringens were isolated from the environment, extensively characterized, and used to formulate a multivalent bacteriophage cocktail designated -401." two in vivo studies were conducted to determine the cocktail's efficacy in controlling necrotic enteritis (ne) caused by c. perfringens. the first study investigated the efficacy of int-401 and a bacteriophage-derived, toxoid-type vaccine in contr ...201020408396
rapidly developing gas gangrene due to a simple puncture wound.gas gangrene, an infection caused by clostridium perfringens, is a potentially fatal and physically disabling disease due to its sometimes incredibly rapid progression. an adolescent boy was referred to our university hospital with a history of nail puncture in the hand that occurred a few hours previously. the physical examination revealed a swollen and tender arm with crepitations up to the shoulder. gas was coming out from the puncture wound with digital pressure on the forearm. the plain rad ...201020531129
organization of the cpe locus in cpe-positive clostridium perfringens type c and d isolates.clostridium perfringens enterotoxin (encoded by the cpe gene) contributes to several important human, and possibly veterinary, enteric diseases. the current study investigated whether cpe locus organization in type c or d isolates resembles one of the three (one chromosomal and two plasmid-borne) cpe loci commonly found amongst type a isolates. multiplex pcr assays capable of detecting sequences in those type a cpe loci failed to amplify products from cpe-positive type c and d isolates, indicati ...201020532170
identification of novel pathogenicity loci in clostridium perfringens strains that cause avian necrotic enteritis.type a clostridium perfringens causes poultry necrotic enteritis (ne), an enteric disease of considerable economic importance, yet can also exist as a member of the normal intestinal microbiota. a recently discovered pore-forming toxin, netb, is associated with pathogenesis in most, but not all, ne isolates. this finding suggested that ne-causing strains may possess other virulence gene(s) not present in commensal type a isolates. we used high-throughput sequencing (hts) technologies to generate ...201020532244
disease producing capability of netb positive isolates of c. perfringens recovered from normal chickens and a cow, and netb positive and negative isolates from chickens with necrotic enteritis.necrotic enteritis is a serious disease of chickens and turkeys caused by clostridium perfringens. recently, a pore forming toxin of c. perfringens, called netb, was reported and suggested to be critical to the development of necrotic enteritis. to investigate further the importance of netb in the development of necrotic enteritis, toxin production and disease producing ability of (1) netb positive isolates recovered from normal chickens, (2) a netb positive isolate recovered from a cow, (3) net ...201020537820
nucleoside phosphorylases from clostridium perfringens in the synthesis of 2',3'-dideoxyinosine.four clostridium perfringens phosphorylases were subcloned, overexpressed and analyzed for their substrate specificity. deod(1) and puna could use a variety of purine substrates, including an antiviral drug 2',3'-dideoxyinosine (ddi). in one-pot synthesis using clostridium phosphorylases, 2',3'-dideoxyuridine and hypoxanthine were converted to ddi at yield of about 30%.201020544534
growth performance, meat quality, and gut microflora of broiler chickens fed with cranberry extract.cranberry fruit components have been reported to have antimicrobial activities against a variety of pathogenic bacteria and to be beneficial for human health. studies on their effects are very limited in animals and especially in chickens. this study investigated the effect of feed supplementation with a commercial cranberry fruit extract (cfe) on the performance, breast meat quality, and intestinal integrity of broiler chickens. twelve hundred male 1-d-old broiler chicks were allocated randomly ...201020548081
standardized comparison of antiseptic efficacy of triclosan, pvp-iodine, octenidine dihydrochloride, polyhexanide and chlorhexidine digluconate.this study presents a comparative investigation of the antimicrobial efficacy of the antiseptics pvp-iodine, triclosan, chlorhexidine, octenidine and polyhexanide used for pre-surgical antisepsis and antiseptic treatment of skin, wounds and mucous membranes based on internationally accepted standards.201020551215
sudden death in lactating inbred mice. clostridium perfringens enteropathy. 201020567227
acute necrotizing cholangiohepatitis with clostridium perfringens: a rare cause of post-transplantation mortality. 201020567577
acute necrotizing cholangiohepatitis with clostridium perfringens: a rare cause of post-transplantation mortality. 201020567578
cell-based biosensor for rapid screening of pathogens and toxins.development and validation of a mammalian cell-based biosensor for application in food defense and food safety was investigated. three prototypes of the biosensor capable of handling different sample types were developed and tested with food and beverages. the sensing element is a b lymphocyte ped-2e9 cell-line, encapsulated in collagen matrix in 3d scaffold. the uniqueness of this biosensor is that it detects analyte interaction with mammalian cells and is able to distinguish pathogenic from no ...201020570502
stabilization of clostridium perfringens collagenase mrna by vr-rna-dependent cleavage in 5' leader sequence.the small rna (srna), vr-rna that is directly regulated by the virr/virs two-component system, regulates many genes including toxin genes such as collagenase (cola) and phospholipase c (plc) in clostridium perfringens. although the vr-rna 3' region is sufficient to regulate the cola and plc genes, the molecular mechanism of toxin gene regulation by vr-rna remains unclear. here, we found that cola mrna is cleaved at position -79 and -78 from the a of the first codon (atg) in the presence of vr-rn ...201020572941
accessibility of cholesterol in endoplasmic reticulum membranes and activation of srebp-2 switch abruptly at a common cholesterol threshold.recent studies have shown that cooperative interactions in endoplasmic reticulum (er) membranes between scap, cholesterol, and insig result in switch-like control over activation of srebp-2 transcription factors. this allows cells to rapidly adjust rates of cholesterol synthesis and uptake in response to even slight deviations from physiological set-point levels, thereby ensuring cholesterol homeostasis. in the present study we directly probe for the accessibility of cholesterol in purified er m ...201020573965
freshwater suspended sediments and sewage are reservoirs for enterotoxin-positive clostridium perfringens.the release of fecal pollution into surface waters may create environmental reservoirs of feces-derived microorganisms, including pathogens. clostridium perfringens is a commonly used fecal indicator that represents a human pathogen. the pathogenicity of this bacterium is associated with its expression of multiple toxins; however, the prevalence of c. perfringens with various toxin genes in aquatic environments is not well characterized. in this study, c. perfringens spores were used to measure ...201020581181
life-threatening clostridial sepsis in a postmenopausal patient with degenerating uterine leiomyoma.clostridium perfringens is a fulminant infection that affects patients with a high rate of morbidity and mortality. fortunately, c. perfringens-associated sepsis and death in the gynecologic patient is rarely encountered. we report a case of intrauterine c. perfringens presenting as life-threatening sepsis in a postmenopausal patient.201020585368
infection status of hospitalized diarrheal patients with gastrointestinal protozoa, bacteria, and viruses in the republic of korea.to understand protozoan, viral, and bacterial infections in diarrheal patients, we analyzed positivity and mixed-infection status with 3 protozoans, 4 viruses, and 10 bacteria in hospitalized diarrheal patients during 2004-2006 in the republic of korea. a total of 76,652 stool samples were collected from 96 hospitals across the nation. the positivity for protozoa, viruses, and bacteria was 129, 1,759, and 1,797 per 10,000 persons, respectively. especially, cryptosporidium parvum was highly mixed ...201020585526
clostridium perfringens in london, july 2009: two weddings and an outbreak.food poisoning outbreaks caused by clostridium perfringens enterotoxin occur occasionally in europe but have become less common in recent years. this paper presents the microbiological and epidemiological results of a large c. perfringens outbreak occurring simultaneously at two weddings that used the same caterer. the outbreak involved several london locations and required coordination across multiple agencies. a case-control study (n=134) was carried out to analyse possible associations betwee ...201020587363
clostridium perfringens enterotoxin carboxy-terminal fragment is a novel tumor-homing peptide for human ovarian cancer.development of innovative, effective therapies against recurrent/chemotherapy-resistant ovarian cancer remains a high priority. using high-throughput technologies to analyze genetic fingerprints of ovarian cancer, we have discovered extremely high expression of the genes encoding the proteins claudin-3 and claudin-4.201020598131
turn a diarrhoea toxin into a receptor-mediated therapy for a plethora of cldn-4-overexpressing cancers.molecular targeted therapy (mtt) represents the new generation of anti-cancer arsenals. in this study, we report an alternative approach using a hybrid toxin that utilises the high-affinity of receptor-binding fragment of clostridium perfringens enterotoxin (cpe). cpe naturally binds to cldn-4 through the c-terminal 30 amino acid. however, recent studies have shown that cldn-4 is also overexpressed on a range of cancer cells. we thus constructed a cdna comprising c-cpe and a well characterised t ...201020599713
tetracycline and penicillin resistant clostridium perfringens isolated from the fangs and venom glands of loxosceles laeta: its implications in loxoscelism treatment.the venom of loxosceles spiders produces severe dermonecrotic damage, intravascular hemolysis, systemic alterations and risk of death. clostridium perfringens is present in the microbial flora of the fangs and venom glands of loxosceles intermedia. its inoculation with the venom may infect the wound site and exacerbate the dermonecrotic damage. this anaerobic bacterium is widely distributed in nature and capable of damage with similar characteristics and severity to the spider venom. in this stu ...201020600224
variable protection after vaccination of broiler chickens against necrotic enteritis using supernatants of different clostridium perfringens strains.necrotic enteritis is an economically important disease of chickens caused by clostridium perfringens. immunity to necrotic enteritis is not fully characterized yet, but previous reports indicate that immunoprotective potential is present in the secreted component of c. perfringens. this study aimed to compare the vaccine potential of the supernatants of eight chicken strains of c. perfringens differing in origin, level of alpha toxin production and presence of netb gene. the supernatant of only ...201020600504
production of an antibacterial substance in the digestive tract involved in colonization-resistance against clostridium perfringens.ruminococcus gnavus e1, bacteroides thetaiotaomicron lemf4, clostridium hathewayi lemc7, and clostridium orbiscindens lemh9 were isolated from ex germ-free mice inoculated with a human faecal microbiota. when initially germ-free mice who were previously inoculated with the strain e1 alone, or a four-strain consortium [e1, lemf4, lemc7, and lemh9], were then challenged with 10⁸ counts of clostridium perfringens; the target strain was rapidly eliminated from the digestive tract of the animals (<10 ...201020603221
cattle enterotoxaemia and clostridium perfringens: description, diagnosis and prophylaxis.cattle enterotoxaemia is one of numerous pathologies caused by clostridium perfringens. these anaerobic gram-positive bacteria are naturally present in the intestinal flora of mammals, but their uncontrolled multiplication under certain conditions results in the overproduction of toxins in the intestinal tract. major clinical signs are induced by the systemic spread of these toxins in the blood and tissues. enterotoxaemia may be acute or peracute, and sudden death is often reported in rapidly gr ...201020605954
comparative proteomic analysis of extracellular proteins of clostridium perfringens type a and type c strains.clostridium perfringens is a medically important clostridial pathogen and an etiological agent causing several diseases in humans and animals. c. perfringens and its toxins have been listed as potential biological and toxin warfare (btw) agents; thus, efforts to develop strategies for detection and protection are warranted. forty-eight extracellular proteins of c. perfringens type a and type c strains have been identified here using a 2-dimensional gel electrophoresis-mass spectrometry (2-de-ms) ...201020605988
crystallization and preliminary crystallographic analysis of the clostridium perfringens enterotoxin.clostridium perfringens is a gram-positive anaerobic species of bacterium that is notable for its ability to produce a plethora of toxins, including membrane-active toxins (alpha-toxins), pore-forming toxins (-toxins) and binary toxins (iota-toxins). here, the crystallization of the full-length wild-type c. perfringens enterotoxin is reported, which is the causative agent of the second most prevalent food-borne illness in the united states and has been implicated in many other gastrointestinal p ...201020606275
clostridial dermatitis and cellulitis: an emerging disease of turkeys.clostridial dermatitis of turkeys (cdt) has emerged as a major issue across most geographic regions of the united states. the prevalence and severity of dermatitis has increased over the last several years, since the time it was first reported in 1993. cellulitis in poultry can be associated with staphylococcus aureus or escherichia coli, but the more recent field situation in turkeys is specifically associated with clostridium spp. the prevalence of cellulitis is relatively low; however, the di ...201020608520
role of clostridium perfringens and clostridium septicum in causing turkey cellulitis.the role of clostridium perfringens and clostridium septicum in the development of cellulitis and mortality in turkey poults was examined. studies were done in turkeys of two age groups: 3-wk-old and 7-wk-old turkey poults. the effect of varying doses of c. perfringens and c. septicum in reproducing cellulitis lesions and mortality in turkeys was investigated. both in vitro and in vivo assays were conducted to study their toxic and biologic activities. clostridium septicum spore culture was foun ...201020608521
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