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water quality in the near coastal waters of the gulf of mexico affected by hurricane katrina: before and after the storm.water quality was assessed following hurricane katrina in the affected waters of alabama, mississippi, and louisiana. post-landfall water quality was compared to pre-hurricane conditions using indicators assessed by epa's national coastal assessment program and additional indicators of contaminants in water and pathogens. water quality data collected after hurricane katrina suggest that the coastal waters affected by the storm exhibited higher salinity and concentrations of chlorophyll a, dissol ...200919484287
[intravascular hemolysis due to clostridium perfringens in an immunocompetent patient]. 200919481305
genetic characterization of type a enterotoxigenic clostridium perfringens strains.clostridium perfringens type a, is both a ubiquitous environmental bacterium and a major cause of human gastrointestinal disease, which usually involves strains producing c. perfringens enterotoxin (cpe). the gene (cpe) encoding this toxin can be carried on the chromosome or a large plasmid. interestingly, strains carrying cpe on the chromosome and strains carrying cpe on a plasmid often exhibit different biological characteristics, such as resistance properties against heat. in this study, we i ...200919479065
rapid detection of intestinal pathogens in fecal samples by an improved reverse dot blot method.to develop a new, rapid and accurate reverse dot blot (rdb) method for the detection of intestinal pathogens in fecal samples.200919469006
the inhibition of lipopolysaccharide-induced tumor necrosis factor-alpha and nitric oxide production by clostridium perfringens alpha-toxin and its relation to alpha-toxin-induced intracellular ceramide generation.the effect of clostridium perfringens alpha-toxin on production of tumor necrosis factor (tnf)-alpha and nitric oxide (no) in lipopolysaccharide (lps)-stimulated raw 264.7 cells was studied. the pretreatment of wild type alpha-toxin, but not the inactive mutant, significantly decreased lps-induced tnf-alpha and no production. alpha-toxin inhibited the expression of tnf-alpha and an inducible type of no synthase protein and mrna. furthermore, it inhibited the phosphorylation of ikappab-alpha and ...200919467928
large outbreak of salmonella phage type 1 infection with high infection rate and severe illness associated with fast food premises.to describe the epidemiology of an outbreak of salmonella enteritidis phage type 1 (pt1) infection associated with a fast food premises, and to identify the causative factors leading to an acute outbreak with high attack rate and severe illness including hospital admission.200919464715
protective effect of potentially probiotic lactobacillus strain on infection with pathogenic bacteria in chickens.the probiotic potential of a lactobacillus salivarius 3d strain isolated from chicken faeces was assessed in one day old chickens. lactobacillus salivarius 3d was administered per os at a concentration of 10(8) cfu in 100 microl of pbs. the chickens were then challenged with pathogenic bacteria: salmonella enteritidis, campylobacter jejuni and clostridium perfringens. samples of caecal contents and livers were collected after 1, 2, 3, 7 and 14 days after infection. lactobacilli and pathogenic ba ...200919459435
claudin-4 augments alveolar epithelial barrier function and is induced in acute lung injury.intact alveolar barrier function is associated with better outcomes in acute lung injury patients; however, the regulation of alveolar epithelial paracellular transport during lung injury has not been extensively investigated. this study was undertaken to determine whether changes in tight junction claudin expression affect alveolar epithelial barrier properties and to determine the mechanisms of altered expression. in anesthetized mice exposed to ventilator-induced lung injury, claudin-4 was sp ...200919447895
contact with enterocyte-like caco-2 cells induces rapid upregulation of toxin production by clostridium perfringens type c isolates.clostridium perfringens type c isolates cause necrotizing enteritis in humans and domestic animals. in vitro, type c isolates often produce beta toxin (cpb), beta2 toxin (cpb2), alpha toxin (cpa), perfringolysin o (pfo) and tpel during (or after) late log-phase growth. in contrast, the current study found that many type c isolates respond to close contact with enterocyte-like caco-2 cells by producing all toxins, except tpel, much more rapidly than occurs during in vitro growth. this in vivo eff ...200919438515
clostridium perfringens beta-toxin binding to vascular endothelial cells in a human case of enteritis necroticans.clostridium perfringens type c-induced enteritis necroticans is a rare but often fatal disease in humans. a consistent histopathological finding is an acute, deep necrosis of the small intestinal mucosa associated with acute vascular necrosis and massive haemorrhage in the lamina propria and submucosa. retrospective immunohistochemical investigations of tissues from a diabetic adult who died of enteritis necroticans revealed endothelial localization of c. perfringens beta-toxin in small intestin ...200919429761
molecular determinants of the interaction between clostridium perfringens enterotoxin fragments and claudin-3.clostridium perfringens enterotoxin (cpe) binds to the extracellular loop 2 of a subset of claudins, e.g. claudin-3. here, the molecular mechanism of the cpe-claudin interaction was analyzed. using peptide arrays, recombinant cpe-(116-319) bound to loop 2 peptides of mouse claudin-3, -6, -7, -9, and -14 but not of 1, 2, 4, 5, 8, 10-13, 15, 16, 18-20, and 22. substitution peptide mapping identified the central motif (148)npl(150)vp, supposed to represent a turn region in the loop 2, as essential ...200919429681
phospholipase c and sphingomyelinase activities of the clostridium perfringens alpha-toxin.alpha-toxin is a major pathogenic determinant of clostridium perfringens, the causative agent of gas gangrene. alpha-toxin has been known for long to be a phospholipase c, but up to now its hydrolytic properties have been studied only through indirect methods, e.g. release of cell contents, or under non-physiological conditions, e.g., in micelles, or with soluble substrates. in this report we characterize the phospholipase c and sphingomyelinase activities of alpha-toxin using a direct assay met ...200919428363
n-acetylglucosamine recognition by a family 32 carbohydrate-binding module from clostridium perfringens nagh.many carbohydrate-active enzymes have complex architectures comprising multiple modules that may be involved in catalysis, carbohydrate binding, or protein-protein interactions. carbohydrate-binding modules (cbms) are a common ancillary module whose function is to promote the adherence of the complete enzyme to carbohydrate substrates. cbm family 32 has been proposed to be one of the most diverse cbm families classified to date, yet all of the structurally characterized cbm32s thus far recognize ...200919422833
sialivac: an intranasal homologous inactivated split virus vaccine containing bacterial sialidase for the control of avian influenza in poultry.a simple, effective inactivated avian flu vaccine composed of three homologous highly pathogenic (hp) h5n1 strains combined with clostridium perfringens type a 107 sialidase/neuramindase and chitosan as a trans epithelial carrier adjuvant applied intranasally to poultry is described. poultry were vaccinated with an inactivated, solvent split, chitosan adjuvanted intranasal (in) vaccine with and without c. perfringens sialidase and the resulting serum igg antibody measured by haemagglutination in ...200919406183
mlst analysis reveals a highly conserved core genome among poultry isolates of clostridium septicum.clostridium septicum is a highly virulent, anaerobic bacterium capable of establishing necrotizing tissue infections and forming heat resistant endospores. disease is primarily facilitated by secretion of numerous toxic products including a lethal pore-forming cytolysin. spontaneously occurring clostridial myonecrosis involving c. septicum has recently reemerged as a concern for many poultry producers. however, despite its increasing prevalence, the epidemiology of infection and population struc ...200919402197
clostridium perfringens liver abscess after pancreatic resection.liver abscess is a rare complication after pancreatectomy. clostridium perfingens is a rare cause of intrahepatic infections.200919388837
dietary protein concentration affects intestinal microbiota of adult cats: a study using dgge and qpcr to evaluate differences in microbial populations in the feline gastrointestinal tract.the objective of this study was to identify qualitative and quantitative differences in microbial populations of adult cats fed diets containing different protein concentrations. following a 4 week baseline period, eight healthy adult domestic short-hair queens (>1-year-old) were randomly allotted to a moderate-protein (mp; n = 4) or high-protein (hp; n = 4) diet for 8 weeks. fresh faecal samples were collected after baseline and 8 weeks on treatment and stored at -80 degrees c. following dna ex ...200919386015
lactobacillus isolates from weaned piglets' mucosa with inhibitory activity against common porcine pathogens.twelve lactobacilli isolates from mucosa of 3-5-week-old weaned pigs were found to exert good antimicrobial activity against common porcine pathogens (s. aureus, b. cereus, e. coli, c. perfringens). two of them produced in addition to lactic acid also considerable amounts of acetic acid, and 6 of them produced hydrogen peroxide and metabolites other than organic acids. isolates 4/26 and 2/25 (identified as l. crispatus or l. amylovorus) were inhibitory against most strains of s. aureus, b. cereu ...200919381487
completion pancreatectomy for treatment of a clostridium perfringens pancreatic infection.pancreatic infection is associated with high morbidity and mortality. drainage of the infection is the usual therapeutic approach. clostridium perfringens infection can cause fulminant sepsis, but it rarely occurs within the pancreas. the case of a 76-year-old man with cystic pancreatic lesions in which sepsis developed after endoscopic ultrasound with fine-needle aspiration biopsy is described. the sepsis was managed with pancreatic resection and antibiotics. clostridium perfringens was isolate ...200919380651
fluorescent in situ hybridization in combination with filter cultivation (fishfc) method for specific detection and enumeration of viable clostridium perfringens.to reduce time for enumeration of viable clostridium perfringens, fluorescence in situ hybridization in combination with filter cultivation (fishfc) was employed. the method utilized a clp-180 probe, based on the 16s rrna region of c. perfringens, and fishfc fluorescence microscopy to detect c. perfringens, but not organisms from other species. optimal cultivation requirements for micro-colony formation were tsc medium, anaerobic conditions, 37 degrees c, and incubation for 6h. under these condi ...200919376466
an outbreak of clostridium perfringens and the enforcement of food safety standards.investigation and management of a possible foodborne outbreak notified to the brisbane northside population health unit aimed to determine the likely source of the outbreak and prevent the same scenario from recurring. environmental health officers inspected the implicated premises and collected legal samples prior to the 1st outbreak control team meeting. interview evidence was carefully documented. inspection revealed large quantities of meat dishes being allowed to cool at room temperature ov ...200819374276
virulence gene regulation by the agr system 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 tissue. the agr system is known to be important for the regulation of virulence genes in a quorum-sensing manner in staphylococcus aureus. a homologue for s. aureus agrbd (agrbd(sa)) was identified in the c. perfringens strain 13 genome, and the role of c. perfringens agrbd (agrbd(cp)) was ...200919363118
gero, a putative na+/h+-k+ antiporter, is essential for normal germination of spores of the pathogenic bacterium clostridium perfringens.the genome of the pathogen clostridium perfringens encodes two proteins, gero and gerq, homologous to monovalent cation transporters suggested to have roles in the germination of spores of some bacillus species. gero and gerq were able to transport monovalent cations (k(+) and/or na(+)) in escherichia coli, and gero and gerq were expressed only in the mother cell compartment during c. perfringens sporulation. c. perfringens spores lacking gero were defective in germination with a rich medium, kc ...200919363115
characterization of a unique class c acid phosphatase from clostridium perfringens.clostridium perfringens is a gram-positive anaerobe and a pathogen of medical importance. the detection of acid phosphatase activity is a powerful diagnostic indicator of the presence of c. perfringens among anaerobic isolates; however, characterization of the enzyme has not previously been reported. provided here are details of the characterization of a soluble recombinant form of this cell-associated enzyme. the denatured enzyme was approximately 31 kda and a homodimer in solution. it catalyze ...200919363079
role of gerkb in germination and outgrowth of clostridium perfringens spores.previous work indicated that clostridium perfringens gerka gerkc spores germinate significantly, suggesting that gerkb also has a role in c. perfringens spore germination. we now find that (i) gerkb was expressed only during sporulation, likely in the forespore; (ii) gerkb spores germinated like wild-type spores with nonnutrient germinants and with high concentrations of nutrients but more slowly with low nutrient concentrations; and (iii) gerkb spores had lower colony-forming efficiency and slo ...200919363077
transcriptional profiling analysis of host response to clostridium perfringens infection in broilers.necrotic enteritis is a disease caused by clostridium perfringens, which threatens poultry production in the absence of dietary antibiotics. a total number of 600 ross broilers were reared in 12 pens with each hosting 50 birds. each 6 pens of birds were fed medicated (bacitracin at 55 mg/kg) or nonmedicated starter diets immediately after the chicks were placed. at d 18, birds were challenged with c. perfringens (10(7) cfu/ml mixed with feed). spleens were collected from 12 birds of each group ( ...200919359691
[a necrotizing fasciitis of an abdominal wall after a cholecystectomy--a case report].the authors present a case review of a patient with a life threatening infectious complication after a routine operation with an accent on urgent diagnosis and treatment. a sepsis with an extensive necrotizing anaerobic infection of the surgical wound with a destruction of abdominal wound developed in 48 hours after a cholecystectomia. the patient status required repeatedly an extensive necrectomy with a hospitalization on an intensive care unit with a necessity of an arteficial pulmonary ventil ...200919358467
occurrence and levels of fecal indicators and pathogenic bacteria in market-ready recycled organic matter composts.landfill diversion of organic wastes through composting is making compost products available for agricultural and horticultural crops. on certified organic farms, nonsludge green waste and manure composts are widely used because the use of these products removes harvest date restrictions imposed by the u.s. department of agriculture when raw manure is applied. we quantified several pathogens in point-of-sale composts from 94 nonsludge facilities processing 2.2 million m3 year(-1) of recycled gre ...200919350977
seasonal relationships among indicator bacteria, pathogenic bacteria, cryptosporidium oocysts, giardia cysts, and hydrological indices for surface waters within an agricultural landscape.the south nation river basin in eastern ontario, canada is characterized by mixed agriculture. over 1600 water samples were collected on a bi-weekly basis from up to 24 discrete sampling sites on river tributaries of varying stream order within the river basin between 2004 and 2006. water samples were analyzed for: densities of indicator bacteria (escherichia coli, clostridium perfringens, enterococci, total and fecal coliforms), the presence of pathogenic bacteria (listeria monocytogenes, e. co ...200919339033
nitrogen, phosphorus, and bacteria tile and groundwater quality following direct injection of dewatered municipal biosolids into soil.application of municipal biosolids (sewage) to agricultural land is a common practice to improve soil physical quality and fertility. the chosen method of land application can have a strong impact on the extent of adjacent water contamination by nutrients and bacteria. dewatered municipal biosolids (dmb) were applied to silt-clay loam experimental field plots in ontario, canada using two application methods: (i) surface spreading followed by shallow incorporation (ss) and (ii) a newly developed ...200919329694
diversifying and stabilizing selection of sialidase and n-acetylneuraminate catabolism in mycoplasma synoviae.sialidase activity varies widely among strains and tends to correlate with strain virulence in the avian pathogen mycoplasma synoviae. to characterize the forms of selection acting on enzymes required for sialic acid scavenging and catabolism, the ratios of nonsynonymous (k(a)) to synonymous (k(s)) mutation frequency were calculated for codons in the sialidase gene of 16 strains of m. synoviae and for its nearly identical homolog in four strains of mycoplasma gallisepticum. the k(a)/k(s) (omega) ...200919329630
case of clostridium perfringens bacteremia after routine colonoscopy and polypectomy.bacteremia is an uncommon complication after polypectomy and colonoscopy. we report one of the first cases of clostridium perfringens bacteremia after polypectomy. our patient was a four years old boy with congenital polyposis, who underwent colonoscopy and polypectomy without complication. approximately 12h later he developed a fever and tachycardia with no other clinical symptoms. his blood cultures grew out penicillin susceptible c. perfringens and enterococcus faecalis. he responded to antib ...200919324098
cellular functions and x-ray structure of anthrolysin o, a cholesterol-dependent cytolysin secreted by bacillus anthracis.anthrolysin o (alo) is a pore-forming, cholesterol-dependent cytolysin (cdc) secreted by bacillus anthracis, the etiologic agent for anthrax. growing evidence suggests the involvement of alo in anthrax pathogenesis. here, we show that the apical application of alo decreases the barrier function of human polarized epithelial cells as well as increases intracellular calcium and the internalization of the tight junction protein occludin. using pharmacological agents, we also found that barrier func ...200919307185
nosocomial and antibiotic-associated diarrhoea caused by organisms other than clostridium difficile.most cases of nosocomial and antibiotic-associated diarrhoea are caused by alteration of the physiological gut microflora. this alteration leads to reduced microbial metabolism of carbohydrates and primary bile acids, resulting in osmotic or secretory forms of diarrhoea. moreover, facultative enteropathogens may experience a growth advantage due to the antibiotic-induced microflora alteration that, in turn, can harm the gut mucosa by the toxins they produce. clostridium difficile is the major in ...200919303568
the oncopathic potency of clostridium perfringens is independent of its alpha-toxin gene.hypoxia in solid tumors is a major obstacle in conventional treatment because of inefficient delivery of therapeutic agents to the lesions, but offers the potential for anaerobic bacterial colonization that can lead to tumor destruction. we have previously reported a recombinant clostridium perfringens (cp) strain constructed by deletion of the superoxide dismutase (sod) gene and insertion of the panton-valentine leukocidin (pvl) gene, cp/sod(-)/pvl, which showed elevated oxygen sensitivity, tum ...200919298132
characterization of two putative fibronectin-binding proteins of clostridium perfringens.clostridium perfringens is a gram-positive anaerobic pathogen that causes gas gangrene and food poisoning in humans and animals. genomic analysis of c. perfringens strain 13 revealed that this bacterium contains two genes (cpe0737 and cpe1847) that encode putative fibronectin (fn)-binding proteins (fbps). these genes, named fbpa and fbpb, were found to be constitutively expressed in all three strains (13, nctc8237, cpn50) of c. perfringens, isolated from gas gangrene of human, that were tested. ...200919292998
cholesterol exposure at the membrane surface is necessary and sufficient to trigger perfringolysin o binding.perfringolysin o (pfo) is the prototype for the cholesterol-dependent cytolysins, a family of bacterial pore-forming toxins that act on eukaryotic membranes. the pore-forming mechanism of pfo exhibits an absolute requirement for membrane cholesterol, but the complex interplay between the structural arrangement of the pfo c-terminal domain and the distribution of cholesterol in the target membrane is poorly understood. herein we show that pfo binding to the bilayer and the initiation of the seque ...200919292457
a rare trifocal presentation of clostridium septicum myonecrosis.gas gangrene or clostridial myonecrosis is a rare, life threatening infection of the muscle that is typically associated with recent surgery or trauma. it usually affects older individuals who suffer from vascular insufficiency or who are immunocompromised. the typical pathogen is clostridium perfringens. atraumatic gas gangrene caused by clostridium septicum is less common and has a unique association with colon cancer. this condition aggressively spreads through the muscular tissue and often c ...200819292235
cross-complementation of clostridium perfringens plc and clostridium septicum alpha-toxin mutants reveals plc is sufficient to mediate gas gangrene.clostridium perfringens and clostridium septicum are the most common causes of clostridial myonecrosis or gas gangrene. although they mediate a similar disease pathology, they elaborate functionally very different alpha-toxins. we used a reciprocal complementation approach to assess the contribution of the primary toxin of each species to disease and found that c. perfringens alpha-toxin (plc) was able to mediate the gross pathology of myonecrosis even in a c. septicum background, although it co ...200919284973
ecological characterization of the colonic microbiota of normal and diarrheic dogs.we used terminal restriction fragment polymorphism (t-rflp) analysis to assess (1) stability of the fecal microbiota in dogs living in environments characterized by varying degrees of exposure to factors that might alter the microbiota and (2) changes in the microbiota associated with acute episodes of diarrhea. results showed that the healthy canine gi tract harbors potential enteric pathogens. dogs living in an environment providing minimal exposure to factors that might alter the microbiota h ...200919282974
lectin activity of the coagulation factor viii/von willebrand complex.the human coagulation factor viii (fviii) is essential in the intrinsic pathway of blood coagulation and circulates mainly as a non-covalently bound complex with the von willebrand factor (vwf). this complex (fviii/vwf) protects fviii from degradation and cellular uptake, although no biological role has been identified yet for this complex. the fviii/vwf complex was purified from a healthy donor's plasma by affinity chromatography on a sepharose 4b-concanavalin a column and was used to determine ...200919282656
generation of single-copy transposon insertions in clostridium perfringens by electroporation of phage mu dna transposition complexes.transposon mutagenesis is a tool that is widely used for the identification of genes involved in the virulence of bacteria. until now, transposon mutagenesis in clostridium perfringens has been restricted to the use of tn916-based methods with laboratory reference strains. this system yields primarily multiple transposon insertions in a single genome, thus compromising its use for the identification of virulence genes. the current study describes a new protocol for transposon mutagenesis in c. p ...200919270116
strategy to inactivate clostridium perfringens spores in meat products.the current study aimed to develop an inactivation strategy for clostridium perfringens spores in meat through a combination of spore activation at low pressure (100-200 mpa, 7 min) and elevated temperature (80 degrees c, 10 min); spore germination at high temperatures (55, 60 or 65 degrees c); and inactivation of germinated spores with elevated temperatures (80 and 90 degrees c, 10 and 20 min) and high pressure (586 mpa, at 23 and 73 degrees c, 10 min). low pressures (100-200 mpa) were insuffic ...200919269568
[spontaneous rupture of a clostridium perfringens liver abscess into the abdominal cavity]. 200919264295
screening escherichia coli, enterococcus faecalis, and clostridium perfringens as indicator organisms in evaluating pathogen-reducing capacity in biogas plants.this study was conducted to identify an indicator organism(s) in evaluating the pathogen-reducing capacity of biogas plants. fresh cow manure containing 10(4) to 10(5) colony forming unit (cfu) per milliliter of escherichia coli and enterococcus faecalis along with an inoculated clostridium perfringens strain were exposed to 37 degrees c for 15 days, 55 degrees c for 48 h, and 70 degrees c for 24 h. c. perfringens was the most heat-resistant organism followed by e. faecalis, while e. coli was th ...200919259627
inferring maps of forces inside cell membrane microdomains.mapping of the forces on biomolecules in cell membranes has spurred the development of effective labels, e.g., organic fluorophores and nanoparticles, to track trajectories of single biomolecules. standard methods use particular statistics, namely the mean square displacement, to analyze the underlying dynamics. here, we introduce general inference methods to fully exploit information in the experimental trajectories, providing sharp estimates of the forces and the diffusion coefficients in memb ...200919257479
the putative coupling protein tcpa interacts with other pcw3-encoded proteins to form an essential part of the conjugation complex.conjugative plasmids encode antibiotic resistance determinants or toxin genes in the anaerobic pathogen clostridium perfringens. the paradigm conjugative plasmid in this bacterium is pcw3, a 47-kb tetracycline resistance plasmid that encodes the unique tcp transfer locus. the tcp locus consists of 11 genes, intp and tcpa-tcpj, at least three of which, tcpa, tcpf, and tcph, are essential for the conjugative transfer of pcw3. in this study we examined protein-protein interactions involving tcpa, t ...200919251842
effect of potassium diformate on growth performance and gut microbiota in broiler chickens challenged with necrotic enteritis.1. the effect of potassium diformate (kdf) on mortality, growth performance, microbial populations, ph and short chain fatty acid concentrations in the intestinal tract of broiler chickens challenged with necrotic enteritis was investigated. 2. an experiment with 1050 cobb male broiler chickens was conducted from 1 to 35 d of age. there were 7 treatment groups: (1) unchallenged negative control, (2) unchallenged kdf (4.50 g/kg feed), (3) challenged negative control, (4) challenged positive contr ...200919234931
whole blood chemiluminescence response in broiler chickens on different experimental diets and challenged with clostridium perfringens.1. objectives: to validate the whole blood chemiluminescence (wbcl) assay in chickens, a simple and rapid method of measuring production of reactive oxygen species by circulating polymorphonuclear (pmn) leukocytes. to determine the physiological response and innate immune response associated with oral challenge with clostridium perfringens in broiler chickens under different nutritional conditions. 2. in experiment 1, birds were orally challenged with c. perfringens 1. type a or sham-challenged ...200919234930
clostridium perfringens infection among inmates at a county jail--wisconsin, august 2008.on august 8, 2008, employees at a wisconsin county jail noted nausea, vomiting, and diarrhea among more than 100 inmates during the early morning inspection. seven inmates were seen by the jail nurse that morning. following jail protocol, guards gave at least 60 inmates bismuth subsalicylate to relieve symptoms, and the jail nurse notified local health department staff members, who suspected a foodborne outbreak at the jail and initiated an investigation. this report summarizes the findings of a ...200919229165
clostridium perfringens intestinal gas gangrene in a preterm newborn. 200919224438
slec is essential for cortex peptidoglycan hydrolysis during germination of spores of the pathogenic bacterium clostridium perfringens.clostridial spore germination requires degradation of the spore's peptidoglycan (pg) cortex by cortex-lytic enzymes (cles), and two clostridium perfringens cles, slec and slem, degrade cortex pg in vitro. we now find that only slec is essential for cortex hydrolysis and viability of c. perfringens spores. c. perfringens slec spores did not germinate completely with nutrients, kcl, or a 1:1 chelate of ca(2+) and dipicolinic acid (ca-dpa), and the colony-forming efficiency of slec spores was 10(3) ...200919218389
structural insight into the mechanism of streptozotocin inhibition of o-glcnacase.despite decades of its use in diabetes research, the mechanism of cytotoxicity of streptozotocin (stz) toward pancreatic beta-islet cells has remained a topic of discussion. although stz toxicity is likely a function of its capacity to promote dna alkylation, it has been proposed that stz induces pancreatic beta-cell death through o-glcnacase inhibition. in this report, we explore the binding mode of stz to a close homolog of human o-glcnacase, btgh84 from bacteroides thetaiotaomicron. our resul ...200919217614
clostridium perfringens beta-toxin targets endothelial cells in necrotizing enteritis in piglets.beta-toxin (cpb) is known to be the major virulence factor of clostridium perfringens type c strains, which cause necrotizing enteritis in pigs, sheep, goats, calves, and humans. the exact mode of action, in particular the cellular targets of cpb in the intestine of naturally affected species, is however still not resolved. to investigate localization of cpb in naturally occurring necrotizing enteritis, we evaluated 52 piglets with spontaneously acquired c. perfringens type c enteritis and 14 co ...200919216036
microbiological quality of ready-to-eat food served in schools in wales, united kingdom.a survey of the general microbiological quality of ready-to-eat food served in schools was undertaken across wales, united kingdom. of the 2,351 samples taken, four were identified as containing unsatisfactory counts of escherichia coli, four contained unsatisfactory counts of staphylococcus aureus, and one contained an unacceptable count of bacillus cereus when compared with guidelines for the microbiological quality of ready-to-eat food published by the united kingdom public health laboratory ...200919205487
establishment of an analytical system for the human fecal microbiota, based on reverse transcription-quantitative pcr targeting of multicopy rrna molecules.an analytical system based on rrna-targeted reverse transcription-quantitative pcr (rt-qpcr) was established for the precise evaluation of human intestinal microbiota. group- and species-specific primer sets for clostridium perfringens, lactobacillus spp. (six subgroups and three species), enterococcus spp., and staphylococcus spp. targeting 16s rrna gene sequences were newly developed for the quantitative analysis of such subdominant populations in human intestines. they were used together with ...200919201979
sporulation and enterotoxin (cpe) synthesis are controlled by the sporulation-specific sigma factors sige and sigk in clostridium perfringens.clostridium perfringens is the third most frequent cause of bacterial food poisoning annually in the united states. ingested c. perfringens vegetative cells sporulate in the intestinal tract and produce an enterotoxin (cpe) that is responsible for the symptoms of acute food poisoning. studies of bacillus subtilis have shown that gene expression during sporulation is compartmentalized, with different genes expressed in the mother cell and the forespore. the cell-specific rna polymerase sigma fact ...200919201796
intra-species growth-inhibition by clostridium perfringens is a possible virulence trait in necrotic enteritis in broilers.necrotic enteritis in broiler chickens is associated with clostridium perfringens type a, carrying the netb toxin. c. perfringens type a is also a member of the normal intestinal microbiota of broilers. clinically healthy chickens carry several different c. perfringens clones in their intestine. in flocks suffering from necrotic enteritis, however, mostly only one single clone is isolated from the gut of all the diseased animals. selective proliferation of these clinical outbreak strains in the ...200919201552
phylogenomic analyses of clostridia and identification of novel protein signatures that are specific to the genus clostridium sensu stricto (cluster i).the species of clostridium comprise a very heterogeneous assemblage of bacteria that do not form a phylogenetically coherent group. it has been proposed previously that only a subset of the species of clostridium that form a distinct cluster in the 16s rrna tree (cluster i) should be regarded as the true representatives of the genus clostridium (i.e. clostridium sensu stricto). however, this cluster is presently defined only in phylogenetic terms, and no biochemical, molecular or phenotypic char ...200919196767
portrait of an enzyme, a complete structural analysis of a multimodular {beta}-n-acetylglucosaminidase from clostridium perfringens.common features of the extracellular carbohydrate-active virulence factors involved in host-pathogen interactions are their large sizes and modular complexities. this has made them recalcitrant to structural analysis, and therefore our understanding of the significance of modularity in these important proteins is lagging. clostridium perfringens is a prevalent human pathogen that harbors a wide array of large, extracellular carbohydrate-active enzymes and is an excellent and relevant model syste ...200919193644
investigation of bioaerosols released from swine farms using conventional and alternative waste treatment and management technologies.microbial air pollution from concentrated animal feeding operations (cafos) has raised concerns about potential public health and environmental impacts. we investigated the levels of bioaerosols released from two swine farms using conventional lagoon-sprayfield technology and ten farms using alternative waste treatment and management technologies in the united states. in total, 424 microbial air samples taken at the 12 cafos were analyzed for several indicator and pathogenic microorganisms, incl ...200819192808
the spma/b and dacf proteins of clostridium perfringens play important roles in spore heat resistance.strains of clostridium perfringens that cause acute food poisoning have been shown to produce spores that are significantly more heat resistant than those of other strains. previous studies demonstrated that the spore core density and the ratio of spore cortex peptidoglycan relative to the germ cell wall were factors that correlated with the heat resistance of a c. perfringens spore. to further evaluate these relationships, mutant strains of c. perfringens sm101 were constructed with null mutati ...200919189487
necrotic enteritis in chickens: a paradigm of enteric infection by clostridium perfringens type a.withdrawal of antimicrobial growth promoters and ionophore coccidiostats has been accompanied by a resurgence in incidence of necrotic enteritis (ne), a severe clostridium perfringens-induced disease which some consider the most clinically dramatic bacterial enteric disease of poultry. lesions, in jejunum and ileum, are focal-to-confluent, often with a tightly adhered pseudomembrane, and hemorrhage is uncommon. the key risk factor for development of ne is an intestinal environment that favors gr ...200919186215
severely impaired production performance in broiler flocks with high incidence of clostridium perfringens-associated hepatitis.historical meat inspection data and production performance data collected from a large poultry processing plant in norway were used to study the association between clostridium perfringens infection and production performance in commercial broiler flocks. the study period was limited to the first 2.5 years after withdrawal of the in-feed antibiotic avoparcin, when necrotic enteritis was frequently seen. high levels of c. perfringens-associated hepatitis at slaughter were used as an indicator of ...200119184877
cholangiohepatitis in chickens induced by bile duct ligations and inoculation of clostridium perfringens.the association of bile duct ligation with the development of cholangiohepatitis due to clostridium perfringens was examined. chickens with only the cystoenteric duct ligated had no significant liver lesions even if c. perfringens was inoculated into the cystoenteric duct. chickens with both the cystoenteric and hepatoenteric ducts ligated had enlargement of the liver with an apparent acinar pattern. histopathologically, proliferation of bile ductules was seen. bile ductules proliferated extensi ...200019184831
demonstration of passive protection in neonatal calves against colibacillosis following immunization of pregnant heifers at 3 months of gestation.enterotoxigenic escherichia coli is one of the primary etiologic agents for diarrhea in neonatal calves. immunization of dams can provide passive protection in neonatal calves; antibodies transferred through colostrum block colonization of bacteria, thereby preventing disease. in this study, healthy pregnant heifers were vaccinated at approximately 3 months of gestation with either a polyvalent oil-adjuvanted vaccine containing inactivated coronavirus, rotavirus, e. coli k99 subunit antigen, and ...200819177333
enhancement of resistance to coccidiosis and necrotic enteritis in broiler chickens by dietary muscadine pomace.muscadine pomace (mp), a by-product of the production of wine and juice from vitis rotundifolia, was dried and tested in chickens for effects on primary resistance to coccidiosis, development of protective immunity after vaccination with live coccidia, and resistance to necrotic enteritis (ne) caused by the joint action of clostridium perfringens and coccidia. to test primary resistance to coccidiosis, 2-wk-old chicks were given 2% or 5% mp in the diet and inoculated with eimeria acervulina and ...200819166057
ulcerative enteritis-like disease associated with clostridium perfringens type a in bobwhite quail (colinus virginianus).ulcerative enteritis-like disease due to clostridium perfringens type a was attributed as the cause of mortality in excess of 50% in a flock of 1000, 10-to-16-wk-old bobwhite quail (colinus virginianus). clinical signs in these birds ranged from sudden death to listlessness, depression, watery white droppings, ruffled feathers, loss of weight, and death in a few days. necropsy of 30 birds revealed multiple deep ulcers of the mucosa throughout the small intestine and ceca, some with perforation a ...200819166055
auranofin disrupts selenium metabolism in clostridium difficile by forming a stable au-se adduct.clostridium difficile is a nosocomial pathogen whose incidence and importance are on the rise. previous work in our laboratory characterized the central role of selenoenzyme-dependent stickland reactions in c. difficile metabolism. in this work we have identified, using mass spectrometry, a stable complex formed upon reaction of auranofin (a gold-containing drug) with selenide in vitro. x-ray absorption spectroscopy supports the structure that we proposed on the basis of mass-spectrometric data. ...200919165513
a multiplex pcr for toxin typing of clostridium perfringens isolates. 200919157726
necrotizing pneumonia and sepsis due to clostridium perfringens: a case report.abstract: clostridia are uncommon causes of pleuropulmonary infection. clostridial species infecting the pleuropulmonary structures characteristically cause a necrotizing pneumonia with involvement of the pleura. most cases have iatrogenic causes usually due to invasive procedures into the pleural cavity, such as thoracentesis or thoracotomy, or penetrating chest injuries. rarely clostridia pleuropulmonary infections are not related to these factors. the clinical course of pleuropulmonary clostr ...200919144160
rainfall simulation in greenhouse microcosms to assess bacterial-associated runoff from land-applied poultry litter.runoff water following a rain event is one possible source of environmental contamination after a manure application. this greenhouse study used a rainfall simulator to determine bacterial-associated runoff from troughs of common bermudagrass [cynodon dactylon (l.) pers.] that were treated with p-based, n-based, and n plus lime rates of poultry (gallus gallus) litter, recommended inorganic fertilizer, and control. total heterotrophic plate count (hpc) bacteria, total and thermotolerant coliforms ...200919141812
ultrasound-induced inactivation of gram-negative and gram-positive bacteria in secondary treated municipal wastewater.the effect of 24khz, high energy ultrasound in the presence and absence of titanium dioxide particles on the destruction of different bacteria groups was studied. applying a total of 1500w/l for 60min (this corresponds to 5400kj/l specific nominal energy), the mean destruction of gram-negative bacteria such as total coliforms, faecal coliforms and pseudomonas spp. was 99.5%, 99.2% and 99.7%, respectively. more recalcitrant to sonolytic inactivation were the gram-positive bacteria clostridium per ...200919131265
bacterial neuraminidase increases il-8 production in lung epithelial cells via nf-kappab-dependent pathway.bacterial neuraminidase, a sialic acid-degrading enzyme, is one of the virulent factors produced in pathogenic bacteria like as other bacterial components. however little is known about whether bacterial neuraminidase can initiate or modify a cellular response, such as cytokine production, in epithelial cells at infection and inflammation. we demonstrate here that bacterial neuraminidase, but not heat-inactivated neuraminidase, up-regulates expression of interleukin-8 (il-8) mrna and protein in ...200919121622
isolation and characterization of bacteriocin-producing bacteria from the gastrointestinal tract of broiler chickens for probiotic use.to isolate and characterize the bacteriocin-producing bacteria (bpb) from the gastrointestinal tract of broiler chickens for probiotic use.200819120666
regional differences in bacterial flora in harbour porpoises from the north atlantic: environmental effects?microbiological findings in harbour porpoises from different regions of the north atlantic were compared. results in animals from the north and baltic seas were evaluated over a period of 18 years for changes in the microbiological flora.200919120613
a conjugative macrolide resistance gene, mef(a), in environmental clostridium perfringens carrying multiple macrolide and/or tetracycline resistance genes.to determine if environmental clostridium perfringens carry antibiotic resistance genes and if the genes are mobile.200919120611
genotyping of clostridium perfringens isolated from calves with neonatal diarrhea.neonatal diarrhea is one of the main causes of losses in cattle herds. clostridium perfringens is a widespread enteropathogen, and is responsible for many animal diseases such as bovine neonatal diarrhea. fecal samples from 141 diarrheic calves and 129 healthy calves, aged up to 28 days and belonging to three herds were examined. rates of culture positivity were 36.2% and 30.2% for diarrheic and nondiarrheic calves, respectively. multiple isolates from primary isolation plates were subjected to ...200819114113
detection and toxin typing of clostridium perfringens in formalin-fixed, paraffin-embedded tissue samples by pcr.since current microbiology methods are not suitable to detect clostridium perfringens in formalin-fixed, paraffin-embedded tissue samples, we developed a pcr assay to detect toxin-encoding genes and the 16s rrna gene of c. perfringens. we successfully detected and genotyped c. perfringens in tissue sections from two autopsy cases.200919109478
occurrence of cryptosporidium oocysts and giardia cysts in norwegian groundwater wells in bedrock.the occurrence of cryptosporidium oocysts and giardia cysts in norwegian groundwater wells in bedrock has been investigated for the first time. wells close to risk areas such as farming and septic tanks were chosen. in all, 20 water samples from 20 different waterworks were collected. the samples were analysed for cryptosporidium and giardia, using us epa method 1623. turbidity was also measured. water samples from 10 of the waterworks were also analysed for clostridium perfringens by membrane f ...200819108559
[acute emphysematous cholecystitis: x-ray diagnosis]. 200819106871
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
enumeration of some cultivable bacterial groups and characterization of some abiotic variables in the jejunoileal content of prim'holstein veal calves.a study was conducted to characterize the bacterial and biochemical composition of the jejunoileal content of veal calves and the effect of pre-slaughter fasting time. at 22 wk of age, 22 preruminant prim'holstein calves fed milk replacer and pellets (mainly composed of corn) were slaughtered at 6, 12, or 24 h after their last meal. chyme samples were collected from the jejunoileal compartment just after slaughter, and ph and redox potential were immediately measured. culture-based methods were ...200919098252
in vitro effects of alpha toxin from clostridium perfringens on the electrophysiological parameters of jejunal tissues from laying hens preincubated with inulin and n-acetyl-l-cysteine.the present report demonstrates the effect of alpha toxin from clostridium perfringens on electrophysiological indexes of jejunal mucosa from laying hens pretreated with inulin and n-acetyl-l-cysteine (acc), a mucolytic agent. in a first set of experiments, the effect of alpha toxin with or without pretreatment with acc on the electrophysiological parameters was determined when jejunal tissues from laying hens were mounted in ussing chambers. the short-circuit current remained unchanged when alp ...200919096074
effects of diet type and enzyme addition on growth performance and gut health of broiler chickens during subclinical clostridium perfringens challenge.the effects of diet type (corn- vs. wheat-based) and multicarbohydrase addition on growth performance, digesta ph and viscosity, intestinal populations of clostridium perfringens and lactic acid bacteria, and gut lesion score (from 0 to 4, where 0 = no gross lesions, 4 = severe extensive necrosis) of broiler chickens during oral challenge with c. perfringens (none or 10(8) cfu/bird on d 13) were studied in a 39-d experiment. a total of 1,216 male ross-308 chickens was assigned to 8 dietary treat ...200919096067
[clostridial brain abscess after glioblastoma resection: case report and critical review of the literature].clostridium perfringens is rare in neurosurgery. the source of clostridial brain abscess is usually a penetrating head injury. we report the case of a 57-year-old man who had parietal glioblastoma resection with local carmustine chemotherapy and who presented a clostridial brain abscess three weeks later. progression was especially brutal, leading to patient's death in few hours. we discuss the etiology and progression of this case compared to the data reported in the literature.200919095271
claudin expression in rectal well-differentiated endocrine neoplasms (carcinoid tumors).claudins are the structures and functional components of tight junctions and have crucial roles in the maintenance of cell polarity, cellular arrangement, adhesion and paracellular transport. various claudins are expressed in different epithelial cells and most tissues express multiple claudin proteins. the altered expression of claudins has been reported in various human carcinomas, but their expression in rectal well-differentiated endocrine neoplasms (carcinoid tumors), the most common endocr ...200919082451
prevalence of netb among some clinical isolates of clostridium perfringens from animals in the united states.a previously unknown pore forming toxin, called netb toxin, which is produced by some australian strains of clostridium perfringens has recently been reported. this toxin was reported to be critical to the development of the disease necrotic enteritis, in chickens. to investigate the occurrence of the toxin gene (netb) in non-australian c. perfringens strains, one hundred and six american isolates of c. perfringens were examined. ninety-two isolates were from chickens, and 14 were from cattle. t ...200919081686
[microbiology and management of gaseous gangrene:the sichuan experience of 20 earthquake cases].wound secretion from 20 patients with gaseous gangrene was collected for gram staining, bacterial culture and drug sensitivity tests. the results indicated that gaseous gangrene was caused by the co-infection of both aerobic and anaerobic bacteria. gram-negative bacilli were slightly more common than other aerobic bacteria in gaseous gangrene wound, which was different from the findings of ordinary gaseous gangrene.200819080191
sequence variation in the alpha-toxin encoding plc gene of clostridium perfringens strains isolated from diseased and healthy chickens.the aim of the present study was to analyse the genetic diversity of the alpha-toxin encoding plc gene and the variation in alpha-toxin production of clostridium perfringens type a strains isolated from presumably healthy chickens and chickens suffering from either necrotic enteritis (ne) or cholangio-hepatitis. the alpha-toxin encoding plc genes from 60 different pulsed-field gel electrophoresis (pfge) types (strains) of c. perfringens were sequenced and translated in silico to amino acid seque ...200919070974
tight junctions as targets of infectious agents.the epithelial barrier is a critical border that segregates luminal material from entering tissues. essential components of this epithelial fence are physical intercellular structures termed tight junctions. these junctions use a variety of transmembrane proteins coupled with cytoplasmic adaptors, and the actin cytoskeleton, to attach adjacent cells together thereby forming intercellular seals. breaching of this barrier has profound effects on human health and disease, as barrier deficiencies ha ...200919059200
extracellular protectants produced by clostridium perfringens cells at elevated temperatures.the mechanisms of adaptation of clostridium perfringens to high temperatures are not well understood. in this work, the involvement of extracellular compounds in protection to heat was determined.200919055630
antimicrobial activity of essential oils and structurally related synthetic food additives towards clostridium perfringens.to assess the potential of essential oils and structurally related synthetic food additives in inhibiting the growth of clostridium perfringens for the control of necrotic enteritis in chickens.200919054237
the effects of several organic acids on growth performance, nutrient digestibilities, and cecal microbial populations in young chicks.four experiments were conducted to evaluate the effects of citric, gluconic, fumaric, and malic acids on growth and nutrient digestibility in new hampshire x columbian male chicks from hatch to 21 d. for growth performance, chicks fed 1 to 4% gluconic acid, 4% citric acid, or 4% malic acid in a corn-soybean meal diet generally showed reductions (p < 0.05) in growth to 21 d, whereas 3% citric acid, 2% malic acid, or 1.5 to 4.5% fumaric acid had no significant effect. in the first experiment, 2, 4 ...200819038814
clostridium perfringens keratitis leading to blinding panophthalmitis.the purpose of this study was to report a case of clostridium perfringens keratitis, which led rapidly to panophthalmitis, with loss of the eye in a healthy patient.200819034143
assessment of the microbiological safety of dried spices and herbs from production and retail premises in the united kingdom.a study of dried spices and herbs from retail and production premises to determine the microbiological status of such products was undertaken in the uk during 2004. according to ec recommendation 2004/24/ec and european spice association specifications, 96% of 2833 retail samples and 92% of 132 production batches were of satisfactory/acceptable quality. salmonella spp. were detected in 1.5% and 1.1% of dried spices and herbs sampled at production and retail, respectively. overall, 3.0% of herbs ...200919028303
rbcg induces strong antigen-specific t cell responses in rhesus macaques in a prime-boost setting with an adenovirus 35 tuberculosis vaccine vector.bcg vaccination, combined with adenoviral-delivered boosts, represents a reasonable strategy to augment, broaden and prolong immune protection against tuberculosis (tb). we tested bcg (ssi1331) (in 6 animals, delivered intradermally) and a recombinant (rbcg) afro-1 expressing perfringolysin (in 6 animals) followed by two boosts (delivered intramuscullary) with non-replicating adenovirus 35 (rad35) expressing a fusion protein composed of ag85a, ag85b and tb10.4, for the capacity to induce antigen ...200819023426
clostridium perfringens delta toxin is sequence related to beta toxin, netb, and staphylococcus pore-forming toxins, but shows functional differences.clostridium perfringens produces numerous toxins, which are responsible for severe diseases in man and animals. delta toxin is one of the three hemolysins released by a number of c. perfringens type c and possibly type b strains. delta toxin was characterized to be cytotoxic for cells expressing the ganglioside g(m2) in their membrane. here we report the genetic characterization of delta toxin and its pore forming activity in lipid bilayers. delta toxin consists of 318 amino acids, its 28 n-term ...200819018299
effects of dietary mannanoligosaccharide on growth performance, nutrient digestibility and gut development of broilers given different cereal-based diets.a feeding trial was conducted to evaluate the effects of mannanoligosaccharide (mos) on the growth performance, nutrient digestibility and gut development of broilers given a corn or a wheat-based diet over a 21-day experimental period. dietary mos improved the growth performance of birds given the wheat-based diet compared to that of birds given the corn-based diet during 7-21 days of age. in line with this, the ileal digestibility of starch was increased by mos at 21 days of age. the addition ...200819012610
microbial quality control of raw ground beef and fresh sausage in casablanca (morocco).in this study, samples of raw ground beef (n = 150) and fresh sausage (n = 100) were collected randomly from butcheries, supermarkets, and fast-food shops, in casablanca, morocco. two types of meat product samples were considered, one with spices (n = 115) and other without spices (n = 135). all the samples were analyzed for the presence of the following bacteria: escherichia coli, staphylococcus, clostridium perfringens, salmonella, and listeria monocytogenes. e. coli strains were further typed ...200819004395
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