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solid-phase radioimmunoassays for quantitative antibody determination of clostridium perfringens type d epsilon toxin.two reversed solid-phase radioimmunoassays were developed for quantitative determination of antibodies against clostridium perfringens type d epsilon toxin. 125i-labeled prototoxin was used in the bromoacetylcellulose-bound antibody method and in the antibody-coated tube method. the antibody values which can be detected by the assays are in the range of 0.004 iu/ml of investigated serum. the methods allow the screening investigation of large groups of vaccinated sheep in a rapid and inexpensive ...1975172010
studies on epsilon-prototoxin of clostridium perfringens type d. physicochemical and chemical properties of epsilon-prototoxin.epsilon-prototoxin of clostridium perfringens type d consists of one polypeptide chain of 311 amino acids with the following composition: asp52 thr31 ser25 glu28 pro12 gly17 ala14 val28 met5 ile15 leu18 tyr17 phe8 lys31 his2 arg5 tyr2. it has no free cysteine but contains one blocked cysteine. the n-terminal as well as the c-terminal residue is lysine. the ultracentrifuge pattern gave one single boundary having s020,w = 2.15 s and do20,w = 5.56-10(-7) cm2/s. calculation of the molecular weight f ...1975172146
an enterotoxin produced by clostridium perfringens type d. purification by affinity chromatography.clostridium perfringens type d 9867 produced enterotoxin immunologically identical to that produced by types a and c which are responsible for c. perfringens food poisoning. enterotoxin from type c 5386 and type d 9867 was produced in duncan og strong sporulation medium (ds medium). the supernatant fluid from ds-cultures was used for purification of the enterotoxin by affinity chromatography on a monospecific anti-enterotoxin-coupled cnbr activated-sepharose 4b and activated ch-sepharose 4b colu ...1976187011
solid-phase radioimmunoassays for quantitative antibody determination of bacterial exotoxins. measurement of clostridium perfringens type d epsilon antitoxin.two reversed solid-phase radioimmunoassays have been developed for quantitative determination of antibodies against clostridium perfringens type d epsilon toxin. 125i labelled prototoxin was used in the bromoacetyl cellulose-bound antibody method and in the antibody coated tube method. the procedures are based on the competition for 125i labelled prototoxin between the insoluble antibodies and the antibodies present in the unknown sample. the radioactivity bound to solid-phase is in inverse rati ...1976187514
structural studies on epsilon-prototoxin of clostridium perfringens type d. localization of the site of tryptic scission necessary for activation to epsilon-toxin. 1977199192
reverse phase passive haemagglutination and single radial immunodiffusion to detect epsilon antigen of clostridium perfringens type d.two in vitro immunological assays were developed for detection of the epsilon (epsilon) antigen of cl. perfringens type d. it was found that the reverse phase passive haemagglutination assay (rpha) was able to detect concentrations of epsilon-antigen as low as 6 x 10-7 mg/ml whereas the single radial immunodiffusion techniques (srid) was capable of detecting concentrations of epsilon-antigen above 0.01 mg/ml. when applied to gut contents from freshly dead infected sheep the rpha test was found t ...1978223537
comparison of the nucleotide sequence and development of a pcr test for the epsilon toxin gene of clostridium perfringens type b and type d.the sequence of the epsilon toxin gene of clostridium perfringens type d was determined and compared with that of the previously reported type b sequence. it showed two nucleotide changes in the open reading frame, giving rise to one amino acid substitution. the promoter sequences were not homologous, and different putative -35 and -10 regions have been identified in each. the sequence information was used to develop pcr primers which were specific for the epsilon toxin gene. the utility of this ...19921427007
an immunohistochemical study of plasma albumin extravasation in the brain of mice after the administration of clostridium perfringens type d epsilon toxin. 19921445075
evaluation of enzyme-linked immunosorbent assay for diagnosis of clostridium perfringens enterotoxemias.two double sandwich enzyme-linked immunosorbent assays (elisa) for clostridium perfringens beta and epsilon toxins were assessed for routine diagnosis of enterotoxemias on intestinal contents of 151 sheep that died suddenly. conventional tests (mouse assay and culture of organism) showed that 21 specimens were positive for clostridium perfringens type c (beta toxin) and 39 were positive for clostridium perfringens type d (epsilon toxin) enterotoxemias. comparison of the elisa results with conven ...19921496812
clinical signs, treatment, and postmortem lesions in dairy goats with enterotoxemia: 13 cases (1979-1982).enterotoxemia attributable to clostridium perfringens type d in goats is difficult to diagnose because of a lack of specific clinical signs or postmortem lesions, on which to base the diagnosis. this report describes the clinical signs, postmortem lesions, and clinical responses to treatment and vaccination in 4 goat herds, in which a diagnosis of enterotoxemia was confirmed. four clinical cases had the diagnosis confirmed on the basis of signs of diarrhea or sudden death and the isolation of c ...19921559880
anti-idiotypic antibody-induced protection against clostridium perfringens type d.a monoclonal antibody (balb/c mouse) with specificity for a neutralizing epitope on the epsilon-toxin produced by clostridium perfringens type d was used to raise anti-idiotypic antibodies (anti-id) in different strains of mice and rabbits. these were purified and used in cross-immunization studies to induce anti-(anti-idiotype). all strains of mice and rabbits immunized with balb/c-derived anti-id showed a high-titer antibody response directed towards the active site of the toxin. this protecte ...19901695203
an alternative to the toxin neutralization assay in mice for the potency testing of the clostridium tetani, clostridium septicum, clostridium novyi type b and clostridium perfringens type d epsilon components of multivalent sheep vaccines.potency testing of veterinary vaccines containing clostridial antigens currently requires the vaccination of laboratory rabbits followed by the determination of specific antitoxin concentration in the rabbit sera by toxin neutralization test in mice. elisas are described as an alternative method to toxin neutralization for the determination of clostridium tetani, clostridium septicum, clostridium novyi type b and clostridium perfringens type d epsilon antitoxins. the assays were found to be rapi ...19911797039
differences in signs and lesions in sheep and goats with enterotoxemia induced by intraduodenal infusion of clostridium perfringens type d.enterotoxemia was induced in 4 lambs and 4 goat kids by continuous intraduodenal infusion of a whole culture of clostridium perfringens type d. clinical signs, hematologic values, biochemical alterations, and postmortem lesions in the lambs and goat kids were compared. the 4 lambs and 4 goat kids died within 25 hours of beginning the infusions. lesions were not observed in the gastrointestinal tract of the 4 lambs; however, severe hemorrhagic enterocolitis was found in the 4 goat kids. this diff ...19911892271
the effect of passive immunization on active immunity against clostridium perfringens type d in lambs.lambs in different stages of development of active immunity against clostridium perfringens type d were treated with partially purified immunoglobulin in an attempt to superimpose a passive immunity on an existing or developing active immunity. three different studies were undertaken to determine the impact of partial purified immunoglobulins on these vaccinated animals. in 2 of the 3 studies, active immunity was induced by administering the normal routine enterotoxaemia vaccinations and allowin ...19892560536
steam quality and effective sterilization.faced with using steam from a commercial utility having boilers greater than 5 miles distant and being the last user on the system resulted in ineffective sterilization. a three phase testing program was established utilizing: direct physical measurements - an ellison model 915a portable steam calorimeter. direct microbiology - autoclaved feed pellets were aseptically placed in fluid thioglycolate medium and incubated at 37 degrees c. indirect microbiology - feces from "defined flora" mice fed t ...19852862643
enterotoxaemia caused by clostridium perfringens type d in farmed fallow deer. 19852866762
detection of clostridium perfringens epsilon toxin by elisa.an enzyme-linked immunosorbent assay (elisa) has been developed as an alternative to neutralisation tests in mice to detect clostridium perfringens type d epsilon toxin in the intestinal contents of animals which have died from suspected enterotoxaemia. the test was sensitive and quantitative and gave excellent agreement with the mouse protection test.19872884704
the passive protection of lambs against clostridium perfringens type d with semi-purified hyperimmune serum.weaned lambs, having a detectable level of maternal antibodies (1-2 units/ml) against c. perfringens type d, showed protective antitoxin levels lasting for 29 days after receiving a single parenteral dose of 200 units/kg hyperimmune serum. lambs, having no maternal antibodies (less than 0,07 units/ml) to c. perfringens type d but receiving the same dose of hyperimmune serum, maintained protective antibody levels for only 21 days. three weeks after the titres fell below the minimum protective lev ...19882895443
the production and evaluation of monoclonal antibodies to clostridium perfringens type d epsilon toxin.the production of five monoclonal antibodies to the epsilon prototoxin of clostridium perfringens is described. all five monoclonal antibodies located three proteins in a trypsinized preparation of epsilon prototoxin. these proteins were located at 37.6 kdal, 35.6 kdal and 33.7 kdal by western blots. two of the monoclonal antibodies, m26/2 and m27/12, neutralized epsilon toxin in the mouse lethality assay. four of the five monoclonal antibodies are considered suitable as reagents to detect epsil ...19882902095
incorporation of c14 from amino acids and peptides into protein by clostridium perfringens type d.hauschild, andreas h. w. (university of toronto, toronto, ontario, canada). incorporation of c(14) from amino acids and peptides into protein by clostridium perfringens type d. j. bacteriol. 90:1569-1574. 1965.-uptake of c(14) from c(14)-labeled amino acids and peptides by clostridium perfringens was measured in culture media containing acid or papain hydrolysates of c(14)-labeled chlorella protein. between 2 and 4 hr of growth, the rate of c(14) uptake from peptides was higher than from free am ...19654285333
peptides for toxinogenesis of clostridium perfringens type d. 19654285335
selective effect of ph on the production of exocellular protein by clostridium perfringens type d. 19664288499
cytology of spore formation in clostridium perfringens.the sequential morphological events in spore formation by clostridium perfringens type d were observed in ellner's medium where 80 to 100% of the cells formed spores. gross structural changes were studied with the light microscope under phase-contrast, and in fixed cells by the use of both nigrosin and giemsa preparations. fine structure was examined with the electron microscope in both thin sections and frozen-etched preparations. during the first 3 hr of incubation, the original rod-shaped cel ...19684302300
studies on epsilon-prototoxin of clostridium perfringens type d. i. purification methods: evidence for multiple forms of epsilon-prototoxin. 19694305163
[nitrogenous components of the nutrient medium in culturing clostridium perfringens type d]. 19684310429
regulation of aspartokinase activity in clostridium perfringens.cells of clostridium perfringens type d apparently possess only a single species of aspartokinase. this enzyme has been partially purified and shown to be feedback inhibited by meso-diaminopimelate in an allosteric manner. the inhibitor exerts its action noncompetitively with respect to both substrates. the kinetic analysis further indicates that no homotropic cooperative interactions occur between either multiple substrate or inhibitor sites. like aspartokinases from other bacteria, the clostri ...19734353873
clostridium perfringens type d epsilon prototoxin. some chemical, immunological and biological properties of a highly purified prototoxin. 19734369870
histopathological changes in the brain of mice given clostridium perfringens type d epsilon toxin.the distribution, severity and frequency of brain lesions produced in mice by the administration of clostridium perfringens type d epsilon toxin were examined by light microscopy. the granular layer of the cerebellum was the area most frequently affected in mice given single doses of toxin. sequential changes in brain morphology were examined from 1 h to 7 days after injection of toxin. lesions progressed from an initial vasogenic oedema to malacic foci which commonly were focal and bilaterally ...19846088597
ultrastructural changes in the brain of mice given clostridium perfringens type d epsilon toxin.mice were given lethal and sublethal doses of clostridium perfringens type d epsilon toxin and the early morphological changes in perfusion-fixed intoxicated brains were examined from 30 min to 6 h post-inoculation. the initial ultrastructural finding was swelling of astrocytes, especially the perivascular extensions of these cells. astrocytes in the cerebellum appeared to be particularly sensitive to this toxin. these changes were quickly followed by evidence of severe endothelial damage, with ...19846088599
[clostridium perfringens type d enterotoxemia of goats in switzerland. pathologico-anatomical and bacteriological studies]. 19846091266
immune regulatory factors in sheep fetuses.after an antigenic stimulus in vitro, a fraction was found in the supernatant fluids of spleen (s-1) and thymus (t-1) cell cultures of 70 to 80-day-old sheep fetuses infected with ovine adenovirus in utero. the fraction agreed with alpha-1-fetoprotein in mobility and its molecular weight was 67 000. injected into adult sheep, s-1 and t-1 had a suppressive effect on the humoral immune response to both adenovirus and clostridium perfringens d vaccine. tests with peripheral lymphocytes suggested th ...19826283803
vitamin e-enhanced humoral antibody response to clostridium perfringens type d in sheep. 19836301619
effective immunization of lambs against enterotoxaemia.in contrast to adult sheep, 2- to 3-month-old lambs do not respond well to a single injection of clostridium perfringens type d oil adjuvant epsilon toxoid. this unresponsiveness can be overcome, however, by administering 2 injections of oil adjuvant vaccine or one injection of oil adjuvant followed 4 weeks later by an injection of alum-precipitated toxoid. the latter procedure evokes protective antitoxin levels which persist for 8 months, and a booster injection of alum-precipitated toxoid give ...19807231926
an outbreak of enterotoxaemia caused by clostridium perfringens type d in goats in patagonia.forty-four of a flock of 117 angora goats in the rio negro province of argentina died within four days. most of the animals died shortly after the onset of clinical signs, but in a few the clinical course lasted for several days. post mortem the small and large intestines were filled with watery contents, blood and fibrin clots, and there were numerous ulcers on the mucosa. small areas of malacia were observed histologically in the brain. clostridium perfringens type d in pure culture was isolat ...19947817506
molecular cloning of clostridium perfringens epsilon-toxin gene and its high level expression in e. coli.a gene coding for epsilon-toxin was isolated from a field isolate of clostridium perfringens type d by pcr amplification and was cloned under the control of t5 promoter fused with six-histidine tag at the amino terminal end. escherichia coli cells harbouring this construct expressed high levels of the recombinant protein in the form of inclusion bodies. the protein was purified using single step affinity chromatography on a ni(2+)-nitrilotriacetic acid (nta) agarose column. upon immunization of ...19968831683
enterotoxaemia in goats.enterotoxaemia of sheep and goats occurs worldwide, but the condition in goats is poorly understood. the disease in goats is mostly caused by clostridium perfringens type d, although the role of the toxins of this microorganism in the pathogenesis of the disease is not fully understood. the disease occurs in three forms, peracute, acute and chronic, the cardinal clinical sign of the acute and chronic forms being diarrhoea. the main biochemical alterations are hyperglycaemia and glycosuria, while ...19968950829
caprine enterotoxaemia associated with cerebral microangiopathy.cerebral microangiopathy is described in naturally occurring clostridial enterotoxaemia in two goats. the two cases were selected from the files of two diagnostic laboratories in australia, on the basis that the clinical syndrome and history were consistent with a diagnosis of enterotoxaemia, and that the diagnosis was confirmed by the identification of epsilon toxin in the intestinal contents. the lesions consisted of acute perivascular proteinaceous exudate in the brain and bilaterally symmetr ...19979301010
clostridium perfringens type d in a dairy cow. 19989501394
experimental clostridium perfringens type d enterotoxemia in goats.the effects of intraduodenal administration of clostridium perfringens cultures and culture products in goats were evaluated to develop a reliable experimental model of enterotoxemia in this species. five conventionally reared, 11-16-week-old angora goat kids were dosed intraduodenally with whole cultures of c. perfringens type d; five similar animals were dosed with c. perfringens type d filtered culture supernatant; and a third group of five kids was dosed with c. perfringens type d washed cel ...19989539367
detection of alpha- and epsilon-toxigenic clostridium perfringens type d in sheep and goats using a dna amplification technique (pcr).clostridium perfringens isolated from sheep and goat with enterotoxaemia at necropsy and from healthy animals at slaughter were typed using specific pcr assays for the detection of the alpha-, beta- and epsilon-toxin genes. clostridium perfringens isolated from all 52 animals with pathological signs of enterotoxaemia showed the presence of the alpha- and epsilon-toxin genes but were devoid of the beta-toxin gene. these strains could therefore be identified as type d, characteristic for clostridi ...19989674169
neuronal damage produced in rat brains by clostridium perfringens type d epsilon toxin.this paper reports neuronal changes in rat brains subacutely intoxicated with copyright clostridium perfringens type d epsilon toxin. neuronal damage was characterized by either (1) progressive cytoplasmic vacuolation leading to necrosis, or (2) shrunken hyperchromatic cells with nuclear pyknosis. the neuronal injury was also often bilaterally symmetrical, particularly in the brainstem. these findings suggest that, after gaining access to brain tissue by producing an increase in vascular permeab ...199910208737
detection of the etx gene (epsilon-toxin inducer) in plasmids of high molecular weight in clostridium perfringens type d.the purpose of this work is to correlate the production of epsilon-toxin in a set of strains of clostridium perfringens type d with the presence of the etx gene, either genomic or in plasmids. total dna obtained from strains with a different level of toxin production was explored by pcr and all the strains showed the amplification signal. different methods were used to obtain plasmid profiles and all of the bands were assayed by pcr. the detection of the etx gene was only shown in several high m ...199910397325
antibody response in goats vaccinated with liposome-adjuvanted clostridium perfringens type d epsilon toxoid.a trial was performed using 20 goats to evaluate the antibody responses to a liposome-adjuvanted clostridium perfringens epsilon toxoid vaccine (lipv). the antibody response was compared with those produced by epsilon toxoid vaccines prepared using aluminium hydroxide (alv) and incomplete freud's adjuvant (fav). the animals were allocated to four groups at the beginning of the trial. the animals in group 1 were vaccinated with alv, while the animals in group 2 received fav and those in groups 3 ...199910401718
comparison of the effects of clostridium perfringens type d culture supernates in ligated intestinal loops of goats and sheep.the effects of clostridium perfringens type d culture supernates were compared in ligated loops of the small intestine (ileum) and colon of four goat kids and four lambs, the loops being examined histopathologically and electron microscopically 7 h after inoculation. no lesions were observed in the small intestine of any animal, or in control colonic loops. in the caprine and ovine colonic loops treated with culture supernates, most goblet cells were empty and the lumina contained a layer of muc ...199910405305
pcr detection of clostridium perfringens type d in formalin-fixed, paraffin-embedded tissues of goats and sheep.a polymerase chain reaction (pcr) was used to identify the genes encoding the alpha, epsilon and beta toxins of clostridium perfringens in formalin-fixed, paraffin-embedded intestinal tissues of goats and sheep. when pure cultures of cl. perfringens types b and d were used as control templates in the pcr, products of the following sizes were observed on the agarose gel: 247 bp (alpha primers), 1025 bp (beta primers) and 403 bp (epsilon primers). when used to identify cl. perfringens type d in fo ...199910432627
effects of intravenous injection of clostridium perfringens type d epsilon toxin in calves.in cattle, a neurological lesion similar to that produced in sheep and goats by clostridium perfringens type d enterotoxaemia has been reported. however, no causal relationship has been established between this disease and the lesion in cattle. the effects of single and multiple intravenous injections of epsilon toxin in three calves aged 6 months were studied. a further calf was inoculated intravenously with saline solution and used as a control. epsilon toxin invariably produced neurological s ...200211814324
differential conformational environment of tryptophan in epsilon native prototoxin and active toxin from clostridium perfringens type d.the tryptophan content of clostridium perfringens type d epsilon protoxin and toxin was found to be one residue per molecule of protein. n-bromosuccinimide in the presence of urea cleaves the tryptophan with total loss of lethality in both toxin and prototoxin. fluorescence spectroscopy, circular dichroism (cd) and 10% ethylene glycol solvent perturbation studies showed that the tryptophan in epsilon toxin and that in prototoxin have different conformational environments. the tryptophan is more ...200212186772
comparison of four techniques for the detection of clostridium perfringens type d epsilon toxin in intestinal contents and other body fluids of sheep and goats.polyclonal capture enzyme-linked immunosorbent assay (pc-elisa), monoclonal capture elisa (mc-elisa), mouse neutralization test (mnt), and counterimmunoelectrophoresis (ciep), were compared for their ability to detect epsilon toxin in intestinal contents and body fluids of sheep and goats. when used to evaluate intestinal contents of sheep artificially spiked with epsilon prototoxin, pc-elisa detected 0.075 mouse lethal dose (mld)50/ml, whereas the mnt, mc-elisa, and ciep detected 6, 25, and 50 ...200312661718
the early effects of clostridium perfringens type d epsilon toxin in ligated intestinal loops of goats and sheep.clostridium perfringens type d produces enterotoxaemia in goats, sheep and other animals. the disease is caused by c. perfringens epsilon toxin and, while enterotoxaemia in goats is usually characterized by enterocolitis, the disease in sheep is characterized by systemic lesions (such as lung and brain oedema) with minor and inconsistent changes observed in the intestine. a possible explanation for these differences is that epsilon toxin is more promptly absorbed by the ovine than by the caprine ...200312777097
partially purified dried epsilon toxin and toxoid as reagents for the standardization of clostridium perfringens type d bacterin. 195413148492
vaccination of sheep with clostridium perfringens type d vaccines. 195413207581
clostridium perfringens type d (epsilon) enterotoxemia in brown swiss dairy calves. 195613366839
effect of formalin on in vitro and in vivo antigenicity of clostridium perfringens type d e-toxin. 195813539365
enterotoxemia of sheep. ii. distribution of i-131 radioiodinated serum albumin in brains of clostridium perfringens type d intoxicated lambs. 196113708761
some studies on the chemical modification of epsilon-toxin of clostridium perfringens type d. 196313951621
a study of the soluble antigens of clostridium perfringens type d. 196414171648
effect of carbohydrates on toxinogenesis by clostridium perfringens type d. 196514290955
effect of controlled ph on toxinogenesis by clostridium perfringens type d. 196514290959
the pathology of peracute experimental clostridium perfringens type d enterotoxemia in sheep.the pathological findings in sheep with peracute experimental clostridium perfringens type d enterotoxemia are described. of 16 animals inoculated intraduodenally with a whole culture of this microorganism and a starch solution in the abomasum, 12 developed clinical signs including increased respiratory efforts, recumbency, paddling, bleating, convulsions, blindness, and opisthotonus. diarrhea was not observed in any of the animals. the time lapse between the beginning of intraduodenal infusion ...200415460322
production and evaluation of a monoclonal antibody to clostridium perfringens type d epsilon toxin.a monoclonal antibody (mab) against c. perfringens type d epsilon toxin was produced in hybridoma tissue culture supernatant and in balb/c mice ascitic fluid. the mab reacted with single band of the purified epsilon toxin and efficiently neutralized the lethal effect of epsilon toxin in mice. a competitive elisa (c-elisa) was developed using this mab and used to evaluate c. perfringens type d vaccines. individual serum samples from vaccinated rabbits were tested using c-elisa and mouse neutraliz ...200315719625
clostridium perfringens epsilon-toxin increases permeability of single perfused microvessels of rat mesentery.epsilon-toxin, the primary virulence factor of clostridium perfringens type d, causes mortality in livestock, particularly sheep and goats, in which it induces an often-fatal enterotoxemia. it is believed to compromise the intestinal barrier and then enter the gut vasculature, from which it is carried systemically, causing widespread vascular endothelial damage and edema. here we used single perfused venular microvessels in rat mesentery, which enabled direct observation of permeability properti ...200516041001
neurological disorders produced by clostridium perfringens type d epsilon toxin.although the epsilon toxin of clostridium perfringens type d produces disease in many species of domestic livestock, neurological disturbance is more common and better studied in sheep. high levels of circulating toxin, especially in lambs, cause cerebral microvascular endothelial damage with disruption of the blood-brain barrier leading to a severe, diffuse vasogenic oedema and an acute or peracute clinical course to death. with lower toxin levels, or in partially immune sheep, a focal, bilater ...200416701511
evaluation of different fluids for detection of clostridium perfringens type d epsilon toxin in sheep with experimental enterotoxemia.enterotoxemia caused by clostridium perfringens type d is a highly lethal disease of sheep, goats and other ruminants. the diagnosis of this condition is usually confirmed by detection of epsilon toxin, a major exotoxin produced by c. perfringens types b and d, in the intestinal content of affected animals. it has been suggested that other body fluids can also be used for detection of epsilon toxin. this study was performed to evaluate the usefulness of intestinal content versus other body fluid ...200616857397
in vitro effects of clostridium perfringens type d epsilon toxin on water and ion transport in ovine and caprine intestine.clostridium perfringens type d produces enterotoxaemia in sheep, goats and other animals. the disease is caused by c. perfringens epsilon toxin, and while enterotoxaemia in goats is usually characterized by enterocolitis, the disease in sheep is characterized by systemic lesions (such as lung and brain oedema) with minor and inconsistent changes observed in the intestine. a possible explanation for these differences is that epsilon toxin is more promptly absorbed by sheep than goat intestine. in ...200316887702
virulence plasmid diversity in clostridium perfringens type d isolates.clostridium perfringens type d isolates are important in biodefense and also cause natural enterotoxemias in sheep, goats, and occasionally cattle. in these isolates, the gene (etx) encoding epsilon-toxin is thought to reside on poorly characterized large plasmids. type d isolates sometimes also produce other potentially plasmid-encoded toxins, including c. perfringens enterotoxin and beta2 toxin, encoded by the cpe and cbp2 genes, respectively. in the current study we demonstrated that the etx, ...200717339362
development and application of an oral challenge mouse model for studying clostridium perfringens type d infection.clostridium perfringens type d isolates cause enterotoxemia in sheep, goats, and probably cattle. while the major disease signs and lesions of type d animal disease are usually attributed to epsilon toxin, a class b select agent, these bacteria typically produce several lethal toxins. understanding of disease pathogenesis and development of improved vaccines are hindered by the lack of a small-animal model mimicking natural disease caused by type d isolates. addressing this need, we developed an ...200717562765
epsilon-toxin plasmids of clostridium perfringens type d are conjugative.isolates of clostridium perfringens type d produce the potent epsilon-toxin (a cdc/u.s. department of agriculture overlap class b select agent) and are responsible for several economically significant enterotoxemias of domestic livestock. it is well established that the epsilon-toxin structural gene, etx, occurs on large plasmids. we show here that at least two of these plasmids are conjugative. the etx gene on these plasmids was insertionally inactivated using a chloramphenicol resistance casse ...200717720791
lethal effects of clostridium perfringens epsilon toxin are potentiated by alpha and perfringolysin-o toxins in a mouse model.epsilon toxin (etx) is the most important virulence factor of clostridium perfringens type d. two other important toxins, alpha toxin (cpa) and perfringolysin-o (pfo), are encoded and potentially produced by most c. perfringens type d isolates. the biological effects of these toxins are dissimilar although they are all lethal. since the possible interaction of these toxins during infection is unknown, the effects of cpa and pfo on the lethal activity of etx were studied in a mouse model. mice we ...200817997054
binding of epsilon-toxin from clostridium perfringens in the nervous system.epsilon-toxin (epsilon-toxin), produced by clostridium perfringens type d, is the main agent responsible for enterotoxaemia in livestock. neurological disorders are a characteristic of the onset of toxin poisoning. epsilon-toxin accumulates specifically in the central nervous system, where it produces a glutamatergic-mediated excitotoxic effect. however, no detailed study of putative binding structures in the nervous tissue has been carried out to date. here we attempt to identify specific accep ...200818406080
aquaporin-4 in acute cerebral edema produced by clostridium perfringens type d epsilon toxin.sheep, particularly lambs, with high circulating levels of clostridium perfringens type d epsilon toxin develop severe neurologic signs and often die suddenly. on microscopic examination, in the brain, there is microvascular endothelial injury and diffuse vasogenic edema. the aquaporin (aqp) family of membrane water-channel proteins, especially aqp-4, is important in the regulation of water balance in the brain and facilitates reabsorption of excess fluid. in rats given epsilon toxin, generalize ...200818487486
naturally acquired antibodies against clostridium perfringens epsilon toxin in goats.clostridium perfringens type d-producing epsilon toxin is a common cause of death in sheep and goats worldwide. although anti-epsilon toxin serum antibodies have been detected in healthy non-vaccinated sheep, the information regarding naturally acquired antibodies in ruminants is scanty. the objective of the present report was to characterize the development of naturally acquired antibodies against c. perfringens epsilon toxin in goats. the levels of anti-epsilon toxin antibodies in blood serum ...200818538416
ulcerative enterocolitis in two goats associated with enterotoxin- and beta2 toxin-positive clostridium perfringens type d.enterotoxemia caused by clostridium perfringens type d in sheep is believed to result from the action of epsilon toxin (etx). however, the sole role of etx in the intestinal changes of the acute and chronic forms of enterotoxemia in goats remains controversial, and the synergistic action of other c. perfringens toxins has been suggested previously. the current study examined 2 goats that were found dead without premonitory clinical signs. gross lesions at necropsy consisted of multifocal fibrino ...200818776108
clostridium perfringens type d epsilon intoxication in one-day-old calves. 200919561353
clinicopathologic features of experimental clostridium perfringens type d enterotoxemia in cattle.this study was designed to experimentally reproduce enterotoxemia by clostridium perfringens type d in cattle and to characterize the clinicopathologic findings of this disease. fourteen 9-month-old calves were inoculated intraduodenally according to the following schedule: group 1 (n = 4), c. perfringens type d whole culture; group 2 (n = 3), c. perfringens type d washed cells; group 3 (n = 5), c. perfringens type d filtered and concentrated supernatant; group 4 (n = 2), sterile, nontoxic cultu ...200919605912
selection of a clostridium perfringens type d epsilon toxin producer via dot-blot test.clostridium perfringens type d produces enterotoxemia, an enteric disease in ruminants, also known as pulpy kidney disease. caused by epsilon toxin, enterotoxemia is a major exotoxin produced by this microorganism. epsilon toxin is also the main component of vaccines against this enteric disorder. in this study, a standardized dot-blot was used to choose strains of c. perfringens type d that are producers of epsilon toxin. clones producing epsilon toxin were chosen by limiting dilution; after th ...200919779698
antibody response to the epsilon toxin of clostridium perfringens following vaccination of lama glama crias.enterotoxaemia produced by clostridium perfringens a, c and d is an important cause of mortality in young llamas. there is no data on antibody responses following vaccination with epsilon toxin.200919801806
molecular cloning and expression of epsilon toxin from clostridium perfringens type d and tests of animal immunization.epsilon toxin produced by clostridium perfringens types b and d causes enterotoxemia in sheep, goats and calves. enterotoxemia can cause acute or superacute disease, with sudden death of the affected animal. it provokes huge economic losses when large numbers of livestock are affected. therapeutic intervention is challenging, because the disease progresses very rapidly. however, it can be prevented by immunization with specific immunogenic vaccines. we cloned the etx gene, encoding epsilon toxin ...201020198582
potency against enterotoxemia of a recombinant clostridium perfringens type d epsilon toxoid in ruminants.enterotoxemia, a disease that affects domestic ruminants, is caused mainly by the epsilon toxin from clostridium perfringens type d. its eradication is virtually impossible, control and prophylaxis are based on systematic vaccination of herds with epsilon toxoids that are efficient in inducing protective antibody production. the use of recombinant toxins is one of the most promising of these strategies. this work evaluates the potency of a cl. perfringens type d epsilon toxoid expressed by esche ...201020670910
enterotoxemia of sheep. iii. clostridium perfringens type d antitoxin titers of normal, nonvaccinated lambs. 196113708763
sialidases affect the host cell adherence and epsilon toxin-induced cytotoxicity of clostridium perfringens type d strain cn3718.clostridium perfringens type b or d isolates, which cause enterotoxemias or enteritis in livestock, produce epsilon toxin (etx). etx is exceptionally potent, earning it a listing as a cdc class b select toxin. most c. perfringens strains also express up to three different sialidases, although the possible contributions of those enzymes to type b or d pathogenesis remain unclear. type d isolate cn3718 was found to carry two genes (nani and nanj) encoding secreted sialidases and one gene (nanh) en ...201122174687
epsilon-toxin production by clostridium perfringens type d strain cn3718 is dependent upon the agr operon but not the virs/virr two-component regulatory system.clostridium perfringens type b and d strains cause enterotoxemias and enteritis in livestock after proliferating in the intestines and producing epsilon-toxin (etx), alpha-toxin (cpa), and, usually, perfringolysin o (pfo). although etx is one of the most potent bacterial toxins, the regulation of etx production by type b or d strains remains poorly understood. the present work determined that the type d strain cn3718 upregulates production of etx upon close contact with enterocyte-like caco-2 ce ...201122167225
enterotoxemi of sheep. i. effects of clostridium perfringens type d toxin on the brains of sheep and mice. 196113708762
effect of clostridium perfringens epsilon toxin on mdck cells.epsilon toxin is one of the major lethal toxins produced by clostridium perfringens type d and b. it is responsible for a rapidly fatal disease in sheep and other farm animals. many facts have been published about the physical properties and the biological activities of the toxin, but the molecular mechanism of the action inside the cells remains unclear. we have found that the c. perfringens epsilon toxin caused a significant decrease of the cell numbers and a significant enlargement of the mea ...200111549414
toxin-induced vasogenic cerebral oedema in a rat model.vasogenic cerebral oedema (vco) was induced in hooded wistar rats by intraperitoneal injection of clostridium perfringens type d epsilon prototoxin. animals were killed, 1 h to 14 d postinjection, by perfusion fixation under general anaesthesia. vco was detected by the presence of endogenous albumin in the brain, visualised by immunocytochemistry. as early as 1 h postinjection, albumin was detected in the walls of cerebral microvessels. maximal diffuse leakage within the neural parenchyma was se ...200011450014
an assessment of the in vitro toxicology of clostridium perfringens type d epsilon-toxin in human and animal cells.the epithelial madin darby canine kidney (mdck) cell line and 17 human cell lines were examined for sensitivity to clostridium perfringens type d epsilon-toxin. mdck cells were confirmed as being sensitive to the toxin. in addition, the caucasian renal leiomyoblastoma (g-402) human cell line was identified as being epsilon-toxin sensitive. using the mts/pms assay system the concentration of toxin reducing cell culture viability by 50% (lc50) was found to be 2 microg/ml in mdck cells. the lc50 fo ...200010773840
resistance of ovine, caprine and bovine endothelial cells to clostridium perfringens type d epsilon toxin in vitro.ovine, caprine and bovine endothelial cells were grown in vitro and challenged with clostridium perfringens type d epsilon toxin to compare their susceptibility to this toxin. madin darby canine kidney (mdck) cells, which are known to be susceptible to epsilon toxin, were used as a positive control. no morphological alterations were observed in any of the endothelial cell cultures tested, even after challenging with doses as high as 1200 mld50/ml of epsilon toxin. mdck cells showed contour round ...199910493114
variability of serum antibody responses of goat kids to a commercial clostridium perfringens epsilon toxoid vaccine.twenty-nine angora goats were used in a trial of a commercial enterotoxaemia (pulpy kidney disease) vaccine. the animals were allocated to four groups, of which three received an initial dose of vaccine, two also received a booster of the same vaccine either 28 or 42 days after the first vaccination, and the fourth remained as an unvaccinated control group. an indirect elisa technique was used to measure the titres of clostridium perfringens type d epsilon antitoxin in serum samples taken before ...19989829304
protection of goats against experimental enterotoxaemia by vaccination with clostridium perfringens type d epsilon toxoid.enterotoxaemia in goats is mainly characterized by enterocolitis, and it has been suggested that the poor efficacy of commercial vaccines in preventing the disease is due to the local action of clostridium perfringens toxin/s within the intestine, where circulating antibodies might not exert their action. five goat kids were vaccinated with an incomplete freund's adjuvant c perfringens type d epsilon toxoid vaccine on three occasions at three-week intervals, four similar kids were vaccinated wit ...19989682431
enzyme linked immunosorbent assay for potency testing of vaccines containing clostridium perfringens type d epsilon-toxoid.for ethical, economic and technical reasons in vivo assays need to be replaced in routine laboratory procedures. based on a method which is already accepted by the british authorities, an indirect elisa has been developed and evaluated for clostridium perfringens type d-containing vaccines. individual and pooled sera of vaccinated rabbits were tested at a single dilution level, the results transferred into iu/ml, and compared with the conventional toxin neutralization test in mice. the elisa was ...19989588107
detection of clostridium perfringens type d epsilon antitoxin in serum of goats by competitive and indirect elisa.indirect and competitive elisa techniques were developed and their ability to detect antibodies to clostridium perfringens epsilon toxin in goat serum was compared. different dilutions of a hyperimmune goat serum, in serum from a colostrum-deprived kid, were used as positive controls, while sera from eleven colostrum-deprived kids were used as negative controls. the epsilon toxin antibodies in the hyperimmune serum were also measured by mouse neutralisation test (mnt). the correlation coefficien ...19979355257
effects of the intravenous administration of clostridium perfringens type d epsilon toxin on young goats and lambs.young goats (n = 18) and lambs (n = 10) were compared in respect of the effects of clostridium perfringens type d epsilon toxin. toxin produced neurological signs within 0.5-3 h of intravenous injection in (1) all of six kids given doses of 250, 185 or 120 mouse lethal doses 50% (mld50)/kg body weight, (2) two of the three kids given 60 mld50/kg, and (3) all of five lambs given 250 or 120 mld50/kg. six kids and three lambs given 45, 30 or 15 mld50/kg, one lamb given 60 mld50/kg, and three kids a ...19979076601
evaluation of a new cytotoxicity assay for clostridium perfringens type d epsilon toxin.a new cytotoxicity assay for determining the activity of epsilon toxin produced by clostridium perfringens type d has been developed. viability of cultured cells was determined by the ability of only live cells to convert 5-(3-carboxymethoxyphenyl)-2-(4,5-dimethylthiazolyl)-3-(4- sulfophenyl)tetrazolium to the coloured product formazan in the presence of phenazine methosulfate. of the 12 cell lines tested, only the mdck cell line was susceptible to epsilon toxin. specificity was confirmed by the ...19947512061
effect of clostridium perfringens epsilon toxin on the cardiovascular system of rats.pressor activity was demonstrated by the intravenous injection of purified epsilon toxin of clostridium perfringens type d but not by that of epsilon prototoxin. the activity was completely abolished by c. perfringens type b or d antiserum, but not by type a, c, or e antiserum. the rise in blood pressure caused by the toxin was accompanied by a decrease in the blood flow in skin without any change of heart rate and electrocardiogram readings. these results indicate that epsilon toxin possesses p ...19836315593
[use of molasses and whey in culture media for the development and production of a toxin from clostridium perfringens type d].this work was undertaken to study the use of molasses and cheese whey in culture media for growth and toxigenic activities of c. perfringens type d. three media were used namely: 1) a modified gordon medium 2) a molasses medium and 3) a whey medium which composition are shown in table 1. the experiments were carried out in a 400 ml microfermentor by using 300 ml of media with automatic ph control (7,0 +/- 0,1) at 37 degrees c. samples were taken for determination of microbial count and toxigenic ...19826101000
[virulence of clostridium perfringens d-the pathogene of sheep enterotexemia]. 19664303711
focal symmetrical encephalomalacia in a goat.focal symmetrical encephalomalacia (fse) is the most prominent lesion seen in the chronic form of enterotoxemia caused by clostridium perfringens type d in sheep. however, this lesion has not been reported in goats. the current paper reports a case of fse in a goat from the state of paraíba in the brazilian semiarid region. as reported by the farmer, 30, 4-48-month-old animals from a flock of 150 goats died after showing nervous signs, including blindness and recumbence, for periods varying betw ...201020807946
clostridium perfringens type d enterotoxaemia in neonatal lambs. 200717558035
pathogenesis of brain damage produced in sheep by clostridium perfringens type d epsilon toxin: a review.microvascular endothelial damage by the epsilon toxin of clostridium perfringens type d appears to be the fundamental cause of cerebral parenchymal injury and lesions occur in a seemingly dose- and time-dependent manner. large doses of circulating toxin produce a severe, generalised, vasogenic cerebral oedema and an acute or peracute clinical course to death. with lower doses of toxin, or in partially immune sheep, focal necrosis, often bilaterally symmetrical, occurs in certain selectively vuln ...200315080445
the development of tolerance to clostridium perfringens type d epsilon-toxin in mdck and g-402 cells.the epithelial madin darby canine kidney (mdck) cell line, caucasian renal leiomyoblastoma (g-402) cells, human small airways epithelial (hsae) cells, human bronchial epithelial (hbe) cells and human renal proximal tubule (hrpt) epithelial cells were examined for sensitivity to clostridium perfringens biotype d epsilon-toxin. mdck and g-402 cells were confirmed as being the only established cell lines that are sensitive to the toxin. hsae, hbe and hrpt epithelial cells were only found to be sens ...200314686482
separation of clostridium perfringens type d toxins. 196514299029
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