| [time of toxin appearance in relation to detectable changes in canned meat artificially contaminated with clostridium botulinum b (preliminary report)]. | | 1981 | 7031828 |
| toxin-producing bacteria in infants. lack of an association with sudden infant death syndrome. | after finding enterotoxigenic (et) escherichia coli in two consecutive cases of sudden infant death syndrome (sids), we initiated a prospective search for et e coli in sids in manitoba; in addition, we looked for toxigenic clostridium botulinum and c difficile. in a 21-month period, small- and large-bowel contents were obtained in 33 cases of sids, from 32 control subjects, and in ten suspected cases of sids. neither c botulinum nor et e coli was isolated from any of these; c difficile was cultu ... | 1981 | 7032280 |
| production of c2 toxin by clostridium botulinum types c and d as determined by its vascular permeability activity. | vascular permeability (vp) activity was demonstrated by intradermal injection of culture supernatants of clostridium botulinum types c and d and strains producing only c2 toxin. the activity was enhanced markedly by treatment with trypsin. it was abolished by antiserum against c2 toxin and by antisera specific for components i and ii of c2 toxin, but not by anti-type c or -type d neurotoxin serum. of 14 strains examined, 10 had vp activity. no vp activity was demonstrated in the culture supernat ... | 1982 | 7033132 |
| epidemiological report: incidence of clostridium botulinum in coastal and inland areas of west java. | | 1981 | 7033599 |
| infant botulism type b in central europe. | a case of moderately severe botulism was diagnosed in a 4 weeks old white female. clostridium botulinum toxin was identified repeatedly in the infant's faeces by means of the mouse protection assay. clostridium botulinum was isolated in pure culture from faecal material. both the organism and the toxin were type b. the onset of illness was characterized by mild constipation, apathy, weak sucking and difficulty with swallowing. incipient, probably aspiration, pneumonia was diagnosed at the same t ... | 1981 | 7036593 |
| effect of temperature on spore germination and vegetative cell growth of clostridium botulinum. | spore germination and vegetative growth of clostridium botulinum type e strain vh at 2 to 50 degrees c were studied. at all of these temperatures, germination began immediately after the addition of the spores to the germination medium. microscopic observations during germination revealed three types of spores: phase bright (ungerminated), phase variable (partially germinated), and phase dark (fully germinated). at all temperatures except 50 degrees c, there was a pronounced lag between the init ... | 1982 | 7036898 |
| preparation and characterisation of homogeneous neurotoxin type a from clostridium botulinum. its inhibitory action on neuronal release of acetylcholine in the absence and presence of beta-bungarotoxin. | 1. large-scale production and purification of complexes between clostridium botulinum neurotoxin and haemagglutinin have been achieved. 2. haemagglutinin-free neurotoxic protein of the complexes was purified to high specific neurotoxicity by affinity chromatography, on p-aminophenyl beta-d-thiogalactopyranoside coupled to sepharose 4b, followed by chromatography on deae-sephacel. 3. the resultant neurotoxin was homogeneous on isoelectric focussing (pi = 6.3) and on dodecylsulphate/polyacrylamide ... | 1982 | 7037406 |
| type c toxicoinfectious botulism in a foal. | | 1982 | 7037720 |
| atypical toxin variant of clostridium botulinum type b associated with infant botulism. | an atypical toxin variant of clostridium botulinum (strain 657) was isolated from the feces of a 6-week-old female infant whose symptoms and clinical history were consistent with infant botulism. toxin detected in the feces and the toxin produced by isolates from the feces and from two rectal swabs could be neutralized by type b botulinal antitoxin only at very high ratios of of antitoxin to toxin in the neutralization mixture. one international unit of type b antitoxin neutralized only about 10 ... | 1981 | 7037830 |
| protective role of human milk against sudden death from infant botulism. | we examined the possibility that human milk and formula milk might differentially affect the severity of the infant botulism because they differ in immunologic composition and in influence on the normal intestinal microflora against which clostridium botulinum must compete. a beneficial effect of human milk was suggested by the different feeding experiences of the moderate, hospitalized patients and the sudden death cases. of patients hospitalized in california, 66% (33/50) were still being nurs ... | 1982 | 7038077 |
| type f infant botulism. | | 1982 | 7039306 |
| effect of plating medium on heat activation requirement of clostridium botulinum spores. | clostridium botulinum 62a and atcc 25763 spores required heat activation for maximum colony formation when plated on reinforced clostridial agar (bbl microbiology systems) but not when plated on botulinum assay medium. spores from strains b-aphis and 53b did not exhibit heat activation when plated on either medium. | 1981 | 7039510 |
| a note on the effect of nitrite inhibition on the metabolism of clostridium botulinum. | | 1982 | 7040327 |
| growth and toxin formation by clostridium botulinum at low ph values. | | 1982 | 7040328 |
| infant botulism. | | 1981 | 7041556 |
| wound botulism in pediatrics. | a 6-year-old boy with congenital deafness sustained compound fractures to his left ulna and radius. six days after the injury, he appeared lethargic, and his illness progressed to respiratory failure within three days. although the wound at the fracture site appeared benign, cultures obtained when the wound was opened grew clostridium botulinum, type b. both the patient's deafness and the appearance of his wound contributed to the delay in diagnosis of wound botulism. differential diagnosis and ... | 1982 | 7041622 |
| laboratory diagnosis in a large outbreak of type a botulism: confirmation of the value of coproexamination. | coproexamination is a vital component of the laboratory evaluation of botulism and is an essential part of the investigation of suspected botulism cases. in april 1978, type a botulism developed in 34 persons who had eaten at a restaurant in a town in new mexico. pretreatment serum specimens, along with stool specimens for toxin assay and culture for clostridium botulinum, were obtained. at least one specimen (serum or stool) was available for each patient. of 30 serum specimens, 16 (53%) were t ... | 1982 | 7041634 |
| susceptibility to enteric botulinum colonization of antibiotic-treated adult mice. | the relationship between the indigenous intestinal microflora of adults and their resistance to the enteric botulinum infection of infant botulism was studied. orogastric challenges of 10(5) type a clostridium botulinum spores were given to adult mice whose gut flora had been altered by feedings of a mixture of erythromycin and kanamycin sulfate. from 80 to 100% of mice became infected when challenged 15 to 60 h after antibiotic administration. the mean infective dose of 2 x 10(4) spores per mou ... | 1982 | 7042567 |
| localization of sites for 125i-labelled botulinum neurotoxin at murine neuromuscular junction and its binding to rat brain synaptosomes. | botulinum neurotoxin, purified to homogeneity from clostridium botulinum (type a), was found to be highly neurotoxic (greater than 8 x 10(7) mouse ld50/mg protein). labelling of this pure neurotoxin with 125i-iodine to high specific radioactivity was achieved without appreciable loss of biological activity. this was used to demonstrate saturable binding sites for this toxin at the neuromuscular junction, following in vivo administration into mice. a demonstrable inhibitory effect of the neuroto ... | 1982 | 7043781 |
| inhibition of clostridium botulinum by antioxidants, phenols, and related compounds. | a total of 75 compounds, including antioxidants, preservatives, gallic acid and p-hydroxybenzoic acid esters, hydroquinones, hydroxyquinolines, phenol derivatives, and related compounds, were screened for their antibotulinal activity in prereduced thiotone-yeast extract-glucose broth. the most effective inhibitors of clostridium botulinum growth and toxin production were long-chain esters of p-hydroxybenzoic acid and gallic acid, antioxidants, and butylphenol derivatives. the antioxidant nordihy ... | 1982 | 7044310 |
| effects of clostridium botulinum toxins on infant and adult mice. | toxic supernatants of many clostridium botulinum type b isolates from various sources, especially those of isolates obtained from cases of infant botulism, appeared to more toxic in infant mice than in adult mice. the significance of this finding in diagnostic situations is discussed. | 1982 | 7044312 |
| [bacteriological examination of botulism (author's transl)]. | | 1982 | 7045465 |
| cases of type c botulism in broiler chickens. | twenty-seven cases of type c botulism were studied in integrated broiler operations on the delmarva peninsula. single and repeated outbreaks in broiler flocks were observed. no botulinum toxin was found in litter and feed samples despite repeated testing. clostridium botulinum type c was cultured from litter, feed, and tissues of morbid and clinically normal chickens sampled from farms in which flocks experienced botulism. clostridium botulinum type c could not be cultured from tissues of clinic ... | 1982 | 7046721 |
| susceptibility of broiler chickens to clostridium botulinum type c toxin. | as broiler chickens aged during the first eight weeks of life, they decreased in susceptibility to the lethal effects of clostridium botulinum type c toxin. eight-week-old broilers were 2,000 times less susceptible to the lethal effects of the toxin than hatched chicks. different broiler crosses showed similar susceptibility to the lethal effects of type c toxin at seven weeks of age, but 2.5 times more toxin was required to produce lethality by oral inoculation than was required by subcutaneous ... | 1982 | 7046722 |
| the enzyme-linked immunosorbent assay (elisa) for the detection and determination of clostridium botulinum toxins a, b, and e. | | 1982 | 7048008 |
| the immunization of broiler chickens against type c botulism. | broiler chickens were inoculated with different amounts of a clostridium botulinum type c toxoid at 1 or 14 or both 1 and 14 days of age. immunity was assessed following challenge with type c botulism toxin at 3, 6, and 8 weeks of age. protection induced by toxoid injection was affected more by time and number of inoculations than by the amount of toxoid administered. single toxoid injections at one day of age furnished poor protection, whereas groups injected at 14 days of age were well protect ... | 1982 | 7049149 |
| [detection of clostridium botulinum and other pathogenic gram-negative bacteria in fecal samples of subjects dying in childhood]. | | 1981 | 7051918 |
| [diagnostic and therapeutic problems of botulism in infants (author's transl)]. | the incidence of botulism remains high. this disease is burdened by a high lethality rate. it is of significant importance for the patient that therapy is instituted sufficiently early. botulism is an intoxication with the toxin of clostridium botulinum. in babies, botulism can be caused also by peroral infection with the bacteria or spores. it appears that intestinal germination to toxin-forming bacteria can occur in babies only. since honey is very frequently contaminated with clostridium botu ... | 1982 | 7062683 |
| serum antibody response to clostridium botulinum toxin in infant botulism. | a serum antibody response has not been previously demonstrated after infection with clostridium botulinum. we developed an enzyme immunoassay for measuring serum antibody to c. botulinum toxins a, b, and e. this assay system detected a specific immunoglobulin g and immunoglobulin m antibody response to c. botulinum toxin in two patients with infant botulism. | 1982 | 7153329 |
| serologic survey for certain zoonotic diseases in black bears in california. | black bears (ursus americanus) from 3 geographic areas of california were tested for antibodies against agents of 6 zoonotic diseases: toxoplasmosis (indirect hemagglutination), q fever (microagglutination), trichinosis (latex particle agglutination), botulism (passive hemagglutination), leptospirosis (plate agglutination), and plague (enzyme-linked immunosorbent assay). of 149 sera tested, 40 (27%) were positive for toxoplasma gondii antibodies and 25 (17%) had antibodies against coxiella burne ... | 1982 | 7174445 |
| binding to mouse brain synaptosomes of clostridium botulinum type e derivative toxin before and after tryptic activation. | clostridium botulinum type e125 i-labelled derivative toxin, both the partially active (intact) and the fully active (nicked) forms, bound to mouse brain synaptosomes. they gave the same kd and bmax values in binding to synaptosomes, although the nicked form possessed a mouse lethal potency about 30 times higher than that of the intact form. these results may indicate that the binding site of the derivative toxin is not modified by tryptic activation and that the binding to synaptosomes is indep ... | 1982 | 7179292 |
| evaluation of coproexamination as a diagnostic test for avian botulism. | fecal extracts and blood sera from 113 ducks showing clinical signs of botulism were examined for clostridium botulinum type c toxin by means of the mouse toxicity test to evaluate coproexamination as a diagnostic procedure, as compared with demonstration of toxin in serum. when death of test mice unprotected with type specific antitoxin (while protected controls survived) was the criterion, 78.8% of the sera and 5.3% of the fecal extracts were positive. when characteristic signs of intoxication ... | 1981 | 7241701 |
| [relationship between clostridium botulinum type a toxin and theophylline derivatives. i. effect of theophylline against toxicity of the toxin for mice (author's transl)]. | | 1980 | 7241811 |
| potentiation of clostridium botulinum toxin aminoglycoside antibiotics: clinical and laboratory observations. | a child with infant botulism became apneic and died while receiving ampicillin and gentamicin therapy. as aminoglycosides have been implicated in the induction and/or exacerbation of neuromuscular blockade, we used an animal model to test the hypothesis that aminoglycosides potentiate neuromuscular blockade of botulinum toxin. in the range of aminoglycoside doses utilized in these experiments, both gentamicin and tobramycin enhance neuromuscular impairment and death of botulinum toxin-exposed mi ... | 1981 | 7243509 |
| naturally occurring and experimentally induced castor bean (ricinus communis) poisoning in ducks. | castor bean (ricinus communis) poisoning accounted for the death of several thousand ducks in the texas panhandle in the fall and winter months of 1969-1971. signs of intoxication resembled those of botulism, except for mucoid, blood-tinged excreta. the most common lesions were severe fatty change in the liver, widely distributed internal petechial hemorrhages or ecchymoses, and catarrhal enteritis. nearly intact castor beans were found in the stomach of one duck during field necropsy. fragments ... | 1981 | 7271655 |
| toxicities of clostridium botulinum type c toxins of different molecular sizes in geese. | clostridium botulinum type c toxin of 16s was more potent as an oral toxin to geese than that of 12s. | 1981 | 7275321 |
| in vitro inactivation of clostridium botulinum toxins types b, c and e by digestive juices of man and ducks. | inactivation of botulinum toxins type b-l, b-m, c-l and e in the digestive juices of man and ducks was determined. botulinum toxins of the m size (b-m and e) lost their toxicity completely in the gastric juices of both man and ducks, but toxins of the l size (b-l and c-l) lost their toxicity only partially. the toxins were hardly affected by duodenal fluid even after exposure to gastric juice. the toxins were not inactivated by cecal fluid from ducks. since human digestive juices and those from ... | 1980 | 7300037 |
| separation of clostridium botulinum type a derivative toxin into two fragments. | two fragments with molecular weights of 105,000 (fragment i) and 58,000 (fragment ii) were separated chromatographically from each other after clostridium botulinum type a derivative toxin adsorbed onto a qae-sephadex column was treated with dithiothreitol and urea. they were antigenic and formed crossing precipitin lines against anti-derivative toxin in agar gel diffusion tests. upon removal of dithiothreitol and urea by dialysis, the two fragments reassembled to reconstruct the derivative toxi ... | 1981 | 7311108 |
| detection of clostridium botulinum type g toxin by enzyme-linked immunosorbent assay. | clostridium botulinum type g toxin was detected and quantified readily with the enzyme-linked immunosorbent assay. with the double-sandwich technique and alkaline phosphatase as the enzyme indicator, c. botulinum toxin type g was detected in quantities equaling those required for one mouse intraperitoneal median lethal dose. the time required for the procedure was approximately 6.5 h, but this requirement could have been reduced to 5.5 h or less with the use of precoated plates stored at -70 deg ... | 1981 | 7316509 |
| [morphologic and histochemical characteristics of the body's response to the administration of clostridium botulinum toxin. viii. histochemical study of catecholamines and various enzymes in the superior cervical sympathetic ganglion following administration of cl. botulinum type b toxin]. | | 1981 | 7331607 |
| subacute cholinergic dysautonomia in childhood. | clinical features of a 10-year-old boy who presented with manifestations of subacute autonomic neuropathy are described. the pupillary abnormalities, reduced tear, sweat and saliva production, and visceral dysfunction suggest a lesion restricted to cholinergic postganglionic endings of the autonomic nervous system. there was no evidence of dysfunction at the neuromuscular junction or elsewhere in the nervous system. the cause of the cholinergic dysautonomia has not been found. clostridium botuli ... | 1981 | 7346195 |
| experimentally induced toxicoinfectious botulism in horses and foals. | four experiments were performed to elucidate the pathogenesis of toxicoinfectious botulism in horses and foals. groups of horses and foals were inoculated with one of the following: (1) crude toxin of clostridium botulinum, type b, given iv, (2) c botulinum spores, given im, (3) c botulinum spores, given im, in necrotic lesions, and (4) c botulinum spores, given orally with and without dexamethasone. toxin of c botulinum in minute amounts is toxic to horses. clostridium botulinum spores produced ... | 1980 | 7369606 |
| a report on the pathology of type a botulism. | an autopsy case of type a botulism, a sacrifice during the first outbreak in japan, was presented. the patient exhibited typical neuromuscular symptoms and died on the 8th day from the onset of illness. type a clostridium botulinum was demonstrated from the stools and the toxin from the blood serum during the course of disease. the infection source of botulinus bacilli, however, was not clarified. the autopsy diagnoses were made as follows; 1) type a botulism, 2) bronchopneumonia, 3) respirator ... | 1980 | 7395518 |
| oral toxicities of clostridium botulinum type c and d toxins of different molecular sizes. | clostridium botulinum type c progenitor toxins of different molecule sizes, c-l (16s) and c-m (12s), were purified from cultures of strains 573, stockholm, and cb-19. c-l toxin showed some hemaggglutinin activity, whereas c-m toxin did not. neither c-l nor c-m toxin was activated upon trypsinization. molecular dissociation of purified type c-l and c-m toxins into toxic and nontoxic components was demonstrated by sucrose density gradient ultracentrifugation and diethylaminoethyl-sephadex chromato ... | 1980 | 7399665 |
| stabilities of clostridium botulinum type b and c toxins in ruminal contents of cattle. | purified l (large) toxins of clostridium botulinum type b and c are more stable than m (medium) toxins in ruminal contents of cattle. that finding suggests that the stabilities of l toxins are in part responsible for the incidence of intoxication of cattle. | 1980 | 7406494 |
| the susceptibility of the mallard duck (anas platyrhynchos) to clostridium botulinum c2 toxin. | most strains of clostridium botulinum type c, after having lost their capacity to produce their dominant toxin (c1) as a result of being "cured" of their prophages, continue to produce c2, a trypsin-activable toxin reported by other investigators. while of relatively low toxicity when administered perorally to the adult mallard duck (anas platyrhynchos), it was highly toxic when given parenterally. by the intravenous route, for example, it was more than 1,000 times as toxic as c1 toxin by the sa ... | 1980 | 7412022 |
| wound botulism. | it is well recognized that food contamination can result in botulism either from ingestion of performed toxin, in classical botulism, or through absorption of toxin from bacteria within the gut, in infant botulism. botulism due to contamination of wounds with clostridium botulinum is not commonly recognized. we report a case of wound botulism occurring in an eight-year-old boy, characterized by early ptosis, dysphagia and dysarthria and then followed by progressive generalized paralysis and fixe ... | 1980 | 7421626 |
| the exposure to humans to nitrite. | although nitrate is more abundant than nitrite in food and the environment in general, it requires reduction by, for instance, bacterial or plant enzymes before it is involved in the nitrosation of amines or amides. part of the exposure of humans to nitrite arises from its use as a food additive where it performs a very useful function in protecting the consumer from pathogenic micro-organisms such as clostridium botulinum. some untreated foodstuffs, such as potatoes, tomatoes and beets, also co ... | 1980 | 7443161 |
| an outbreak of type c botulism in captive monkeys. | in an outbreak of type c botulism in a group of captive primates, six squirrel monkeys, six white throated capuchin monkeys and two weeper capuchin monkeys succumbed rapidly and died. clostridium botulinum type c toxin was detected in the remains of the chopped chicken feed and in nine of 11 blood samples and one of three stomach contents samples from the affected animals. | 1980 | 7456297 |
| [cattle botulism in australia]. | | 1995 | 7474353 |
| purification and assay of recombinant c3 transferase. | | 1995 | 7476431 |
| in vitro adp-ribosylation of rho by bacterial adp-ribosyltransferases. | | 1995 | 7476432 |
| preparation of native and recombinant clostridium botulinum c3 adp-ribosyltransferase and identification of rho proteins by adp-ribosylation. | | 1995 | 7476433 |
| assay for rho-dependent phosphoinositide 3-kinase activity in platelet cytosol. | | 1995 | 7476437 |
| lymphocyte aggregation assay and inhibition by clostridium botulinum c3 adp-ribosyltransferase. | | 1995 | 7476443 |
| inhibition of p21 rho in intact cells by c3 diphtheria toxin chimera proteins. | | 1995 | 7476444 |
| inhibition of lymphocyte-mediated cytotoxicity by clostridium botulinum c3 transferase. | | 1995 | 7476448 |
| neutrophil chemotaxis assay and inhibition by c3 adp-ribosyltransferase. | | 1995 | 7476449 |
| [botulinum poisoning in adults: a case report and differential diagnosis]. | the authors reports the case of a patient with quadriplegia associated with respiratory failure. a few days before, a paralysis of the oculomotor nerves appeared, which rapidly spreads in cranio-caudal fashion. the occurrence of a similar symptomatology in a patients' relative addressed the diagnosis toward a possible clostridium botulinum intoxication. other possible differential diagnoses are reviewed and discussed. | 1995 | 7478077 |
| rho protein regulates tight junctions and perijunctional actin organization in polarized epithelia. | the rho family of gtp-binding proteins regulates actin filament organization. in unpolarized mammalian cells, rho proteins regulate the assembly of actin-containing stress fibers at the cell-matrix interface. polarized epithelial cells, in contrast, are tall and cylindrical with well developed intercellular tight junctions that permit them to behave as biologic barriers. we report that rho regulates filamentous actin organization preferentially in the apical pole of polarized intestinal epitheli ... | 1995 | 7479854 |
| chemiluminescence immunosorbent assay (clisa) and a possibility of the specific detection of soluble antigens of clostridium botulinum type a. | a double antibody version of clisa was demonstrated to be a rapid method (1 h) for detection and quantitative determination of clostridium botulinum toxin antigens in biological samples. the sensitivity of this assay is about ten-fold higher than both elisa and passive hemagglutination test. thus, the double antibody version of clisa appeared to be useful for the control of food products contaminated with cl. botulinum type a bacteria. | 1994 | 7503646 |
| interaction of clostridium botulinum c2 toxin with lipid bilayer membranes. formation of cation-selective channels and inhibition of channel function by chloroquine. | lipid bilayer experiments were performed with the c2-ii binding component of the adp-ribosylating c2 toxin from clostridium botulinum. the trypsin-activated but not the nonactivated form of the protein was able to increase the specific conductance of artificial lipid bilayer membranes by the formation of ion-permeable channels. the channels had on average a single-channel conductance of 55 ps in 0.1 m kcl and were found to be cation-selective and voltage-dependent. the single-channel conductance ... | 1994 | 7515883 |
| botulinum c3 exoenzyme blocks the tyrosine phosphorylation of p125fak and paxillin induced by bombesin and endothelin. | in this study we examined the role of rho p21 in neuropeptide-stimulated tyrosine phosphorylation. intact swiss 3t3 cells were treated with the clostridium botulinum c3 exoenzyme which specifically adp ribosylates and inactivates rho p21. c3 exoenzyme treatment of cells caused a marked decrease in both bombesin- and endothelin-stimulated tyrosine phosphorylation of multiple proteins, including p125 focal adhesion kinase (fak) and paxillin. our results suggest that rho p21 is a component of the s ... | 1994 | 7525357 |
| effect of botulinum c3 exoenzyme on cell growth and cytoskeleton organization in transformed human epidermal cells in culture: a possible role for rho protein in epidermal cells. | we examined the role of rho gene products (rho proteins) on cell growth and cytoskeleton organization in transformed human epidermal cells in culture (hsc-1), using recombinant botulinum c3 exoenzyme which specifically adp-ribosylates rho proteins. incubation of hsc-1 cell lysates with c3 exoenzyme revealed a single [32p]adp-ribosylated protein with a molecular weight of 23,000. this protein was identified as rhoa protein by isoelectric focusing (pi 6.0). addition of c3 exoenzyme to the culture ... | 1994 | 7530992 |
| adp-ribosylation of rho enhances adhesion of u937 cells to fibronectin via the alpha 5 beta 1 integrin receptor. | to examine the role of rho gtp binding proteins in the adhesion of monocytic cells to fibronectin we used the c3 exoenzyme of clostridium botulinum which adp-ribosylates and inactivates rho proteins in situ. treatment of human monocytic u937 cells with c3 exoenzyme (10 micrograms/ml, 24 h) increased adhesion to fibronectin 2-fold but had no effect on adhesion to collagen or huamn serum albumin. the increase in fibronectin adhesion was prevented by antibodies against the alpha 5 and beta 1 integr ... | 1995 | 7537229 |
| the state of actin assembly regulates actin and vinculin expression by a feedback loop. | actin filaments are major determinants of cell shape, motility and adhesion, which control important biological processes including embryonic development and wound healing. these processes are associated with changes in actin assembly, which is regulated by controlling the balance between polymerized and non-polymerized actin. to maintain a significant pool of non-polymerized actin, mechanism(s) linking actin synthesis to its state of polymerization were proposed. we have studied this relationsh ... | 1995 | 7542668 |
| [effectiveness of modified atmospheres against psychrotrophic pathogenic microorganisms in proteinaceous food]. | modified atmosphere packaging (map) of proteinaceous raw foods (meat, poultry and fish) extends their shelf-lives. it is well established that modified atmospheres (ma) inhibit the psychotropic aerobic gram-negative bacteria, the main spoilage microflora of proteinaceous raw foods stored under refrigeration. several researchers have warned about the possible growth of food poisoning microorganisms on them. considering the minimal growth temperatures of pathogens, this review only deals with aero ... | 1995 | 7546447 |
| introduction of recombinant dna into clostridium spp. | | 1995 | 7550739 |
| the sterilization of honey with cobalt 60 gamma radiation: a study of honey spiked with spores of clostridium botulinum and bacillus subtilis. | unprocessed honey is a recognized wound-healing remedy. however, to make clinical use of honey acceptable, it should be sterile. to find the lowest dose of irradiation needed for sterilization, six batches of honey (a-f) were gamma irradiated with 6, 12, 18, 22 and 25 kgy cobalt-60. after a dose of 25 kgy the antibacterial activity was not altered. presumably glucose oxidase (ec 1.1.3.4), which produces hydrogen peroxide, is not easily damaged by irradiation. amylase activity on the other hand w ... | 1995 | 7556583 |
| participation of rhop21 in serum-dependent invasion by rat ascites hepatoma cells. | rat ascites hepatoma cells (mm1 cells) penetrate through a cultured mesothelial cell monolayer (mcl) in the presence of fetal calf serum (fcs), but scarcely do so in its absence. inactivation of rhop21 of mm1 cells by adp-ribosyltransferase c3 resulted in the suppression of this serum effect on the penetration, suggesting that the serum effect was mediated by rhop21. to ascertain this assumption mm1 cells were transfected with an activated (val14) human rhoa cdna (neo/rhoa 1-7). the transfectant ... | 1995 | 7556636 |
| escherichia coli cytotoxic necrotizing factor 1: evidence for induction of actin assembly by constitutive activation of the p21 rho gtpase. | cytotoxic necrotizing factor type 1 (cnf1) induces in hep-2 cells an increase in f-actin structures, which was detectable by fluorescence-activated cell sorter analysis 24 h after addition of this factor to the culture medium. increase in f-actin was correlated with the augmentation of both the cell volume and the total cell actin content. actin assembly-disassembly is controlled by small gtp-binding proteins of the rho family, which have been reported recently to be modified by cnf1 treatment. ... | 1995 | 7558302 |
| transient expression of rhoa, -b, and -c gtpases in hela cells potentiates resistance to clostridium difficile toxins a and b but not to clostridium sordellii lethal toxin. | the bacterial pathogen clostridium difficle synthesizes two high-molecular-weight toxins (a and b), which exhibit toxic effects in vivo and in vitro. here, we present evidence that the major intracellular targets of these two toxins are the rho gtpases. overexpression of rhoa, rhob, or rhoc gtpases in transfected hela cells conferred an increased resistance to toxins a and b, indicating that these toxins cause their cytopathic effects primarily by affecting rho proteins. in addition, toxin a and ... | 1995 | 7558320 |
| g alpha 12 and g alpha 13 stimulate rho-dependent stress fiber formation and focal adhesion assembly. | rho, a member of the ras superfamily of gtp-binding proteins, regulates actin polymerization resulting in the formation of stress fibers and the assembly of focal adhesions. in swiss 3t3 cells, heterotrimeric g protein-coupled receptors for lysophosphatidic acid and gastrin releasing peptide stimulate rho-dependent stress fiber and focal adhesion formation. the specific heterotrimeric g protein subunits mediating rho-dependent stress fiber and focal adhesion formation have not been defined previ ... | 1995 | 7559569 |
| the ras-related small gtp-binding protein rhob is immediate-early inducible by dna damaging treatments. | the low molecular weight gtp-binding proteins rhoa, rhob, and rhoc are characterized as specific substrates for the adp-ribosyltransferase c3 from clostridium botulinum and are supposed to be involved in the organization of the microfilamental network and transformation. rhob is known to be immediate-early inducible by growth factors and protein-tyrosine kinases. since increasing evidence indicates overlapping of growth factor- and uv-induced signal pathways, we studied the effect of uv light an ... | 1995 | 7559652 |
| involvement of the gtp binding protein rho in constitutive endocytosis in xenopus laevis oocytes. | to study an endocytotic role of the gtp-binding protein rhoa in xenopus oocytes, we have monitored changes in the surface expression of sodium pumps, the surface area of the oocyte and the uptake of the fluid-phase marker inulin. xenopus oocytes possess intracellular sodium pumps that are continuously exchanged for surface sodium pumps by constitutive endo- and exocytosis. injection of clostridium botulinum c3 exoenzyme, which inactivates rho by adp-ribosylation, induced a redistribution of virt ... | 1995 | 7559755 |
| botulinal neurotoxin c1 complex genes, clostridial neurotoxin homology and genetic transfer in clostridium botulinum. | the botulinal neurotoxins (bont) associate with non-toxic proteins (antp) by non-covalent bonds to form large complexes. in c. botulinum c, the bont/c1 locus consists of six genes which are organized in three clusters. cluster 1 encompasses the genes of bont/c1 and antp/139 which could be involved in the resistance of the bont/c1 to the acidic ph and protease degradation. the second cluster consists of three genes which encode hemagglutinin components. the last gene encodes a dna binding protein ... | 1995 | 7570637 |
| in situ characterization of clostridium botulinum neurotoxin synthesis and export. | a monoclonal antitoxin/colloidal gold probe and sequential centrifugation were used to study synthesis, translocation and export of clostridium botulinum strain 62a neurotoxin (nt). exponential growth occurred after 5 h of anaerobic incubation of spores and continued for 15-16 h. nt was detected at 15 h using the probe and transmission electron microscopy (tem), 2 h earlier than the first detection by the mouse bioassay. during exponential growth, the probe localized nt primarily in the cytoplas ... | 1995 | 7592120 |
| sphingosylphosphorylcholine rapidly induces tyrosine phosphorylation of p125fak and paxillin, rearrangement of the actin cytoskeleton and focal contact assembly. requirement of p21rho in the signaling pathway. | sphingosylphosphorylcholine (spc), a potent mitogen for swiss 3t3 cells, rapidly induced tyrosine phosphorylation of multiple substrates including bands of m(r) 110,000-130,000 and m(r) 70,000-80,000 in swiss 3t3 cells. focal adhesion kinase (p125fak) and paxillin were identified as prominent substrates for spc-stimulated tyrosine phosphorylation. an increase in tyrosine phosphorylation of p125fak was detected as soon as 30 s after spc stimulation, reaching a maximum after 2.5 min. spc induced t ... | 1995 | 7592646 |
| synergistic activation of rat brain phospholipase d by adp-ribosylation factor and rhoa p21, and its inhibition by clostridium botulinum c3 exoenzyme. | an activator of rat brain phospholipase d (pld) that is distinct from the already identified pld activator, adp-ribosylation factor (arf), was partially purified from bovine brain cytosol by a series of chromatographic steps. the partially purified preparation contained a 22-kda substrate for clostridium botulinum c3 exoenzyme adp-ribosyltransferase, which strongly reacted with anti-rhoa p21 antibody, but not with anti-rac1 p21 or anti-cdc42hs p21 antibody. treatment of the partially purified pl ... | 1995 | 7592744 |
| bordetella bronchiseptica dermonecrotizing toxin stimulates assembly of actin stress fibers and focal adhesions by modifying the small gtp-binding protein rho. | we studied the biochemical mechanism of morphological changes in cells treated with bordetella dermonecrotizing toxin (dnt). dnt caused the morphological changes of serum-starved mc3t3-e1 cells from flat shapes to reflactile ones. these changes were accompanied by the assembly of actin stress fibers and focal adhesions, which is known to be regulated by the small gtp-binding protein rho. clostridium botulinum c3 exoenzyme, which adp-ribosylates and inactivates rho protein, 'rounded' the cells wi ... | 1995 | 7593285 |
| structure and function of clostridium botulinum toxins. | | 1995 | 7603360 |
| involvement of heterotrimeric gtp-binding protein and rho protein, but not protein kinase c, in agonist-induced ca2+ sensitization of skinned muscle of guinea pig vas deferens. | we studied the involvement of protein kinase c (pkc) and a small gtp-binding protein (g-protein), rho, in receptor-mediated ca2+ sensitization of the contractile apparatus of smooth muscle of guinea pig vas deferens. in beta-escin-permeabilized smooth muscle strips, norepinephrine (ne) in the presence of gtp caused further contraction of the preparations at a constant ca2+ level (ca2+ sensitization). prazosin and gdp beta s, a nonhydrolyzable gdp analogue, inhibited ne-induced ca2+ sensitization ... | 1995 | 7616445 |
| possible involvement of botulinum adp-ribosyltransferase sensitive low molecular g-protein on 5-hydroxytryptamine (5-ht)-induced inositol phosphates formation in 5-ht2c cdna transfected cells. | to clarify the involvement of botulinum adp-ribosyltransferase sensitive low molecular g-proteins in 5-hydroxytryptamine (5-ht)-induced stimulation of phosphatidylinositol turnover, we examined the effects of 5-ht on inositol phosphates formation in cos 7 cells transfected with 5-ht2c receptor cdna, but did not in non-transfected or vector-transfected cells. a typical 5-ht2c receptor antagonist mianserin (0.3-3 microm) inhibited the 5-ht-induced inositol phosphates formation. treatment with botu ... | 1995 | 7624049 |
| translocation of activated rho from the cytoplasm to membrane ruffling area, cell-cell adhesion sites and cleavage furrows. | rho small gtp-binding protein regulates various cell functions, such as formation of stress fibers and focal adhesions, cell motility, membrane ruffling, cytokinesis and smooth muscle contraction in mammalian cells and bud formation in the yeast saccharomyces cerevisiae. as to the functioning sites of rho in saccharomyces cerevisiae, we have recently shown that rho1 protein, a homologue of mammalian rhoa, is concentrated to the growth region of the cells where cortical actin patches are clustere ... | 1995 | 7624130 |
| [botulism in infancy]. | according to international references the publication ascertains the etiologic role of neurotoxin producing clostridial spp., other than c. botulinum in infant botulism. authors report on the first hungarian case of infant botulism. the organism isolated -- c. barati -- is responsible only for a small proportion of published cases. authors point out the conjunction of infantile botulism and crib death. | 1995 | 7637966 |
| effect of heat treatment on survival of, and growth from, spores of nonproteolytic clostridium botulinum at refrigeration temperatures. | spores of five type b, five type e, and two type f strains of nonproteolytic clostridium botulinum were inoculated into tubes of an anaerobic meat medium plus lysozyme to give approximately 10(6) spores per tube. sets of tubes were then subjected to a heat treatment, cooled, and incubated at 6, 8, 10, 12, and 25 degrees c for up to 60 days. treatments equivalent to heating at 65 degrees c for 364 min, 70 degrees c for 8 min, and 75 degrees c for 27 min had little effect on growth and toxin forma ... | 1995 | 7646016 |
| type a and b neurotoxin genes in a clostridium botulinum type ab strain. | the genetic structure of neurotoxin genes in a clostridium botulinum strain producing both type a and b neurotoxins (type ab) was investigated. analyses by polymerase chain reaction (pcr) using type-specific primers corresponding to the coding regions for n-terminals of light-chains and c-terminals of heavy-chains of type a and type b neurotoxins, and southern hybridization of total dna showed that the type ab strain i.p.7212 carries at least one copy each of type a and b neurotoxin genes. parti ... | 1995 | 7654232 |
| effects of clostridium botulinum c2 toxin and cytochalasin d on in vitro invasiveness, motility and f-actin content of a murine t-lymphoma cell line. | in order to investigate the role of microfilaments in the crawling movements of lymphoid cells, we have analyzed the effects of botulinum c2 toxin and of cytochalasin d (cytod) on the actin cytoskeleton and on the motility of a bw5147 t-lymphoma-derived cell line. actin was adp-ribosylated by c2 toxin in the living cells, and this resulted in a time and dose-dependent disappearance of f-actin, as assessed by staining with labeled phalloidin. cytod did not affect the amount of polymerized actin, ... | 1995 | 7656900 |
| effect of lysozyme concentration, heating at 90 degrees c, and then incubation at chilled temperatures on growth from spores of non-proteolytic clostridium botulinum. | the heat treatment necessary to inactivate spores of non-proteolytic clostridium botulinum in refrigerated, processed foods may be influenced by the occurrence of lysozyme in these foods. spores of six strains of non-proteolytic cl. botulinum were inoculated into tubes of an anaerobic meat medium, to give 10(6) spores per tube. hen egg white lysozyme (0-50 micrograms ml-1 was added, and the tubes were given a heat treatment equivalent to 19.8 min at 90 degrees c, cooled, and incubated at 8 degre ... | 1995 | 7662337 |
| involvement of botulinum c3-sensitive gtp-binding proteins in alpha 1-adrenoceptor subtypes mediating ca(2+)-sensitization. | the mechanisms of alpha 1-adrenoceptor agonist-mediated sensitization of the contractile apparatus of smooth muscle to ca2+ were studied in beta-escin-permeabilized thoracic arterial smooth muscle of rabbit. addition of norepinephrine (10 microm) plus guanosine 5'-triphosphate (gtp, 50 microm) significantly enhanced ca2+ sensitivity as compared with the addition of 0.3 microm ca2+ alone (pca6.5). in beta-escin-skinned smooth muscle of chloroethylclonidine-treated tissues, the enhancement of ca(2 ... | 1995 | 7664821 |
| identification of glu173 as the critical amino acid residue for the adp-ribosyltransferase activity of clostridium botulinum c3 exoenzyme. | clostridium botulinum c3 exoenzyme specifically adp-ribosylates rho-p21 in eukaryotic cells. trp18 and glu173 of this enzyme were substituted with other amino acids via site-directed mutagenesis. all substitutions at glu173 caused a significant reduction in affinity for nad and diminished adp-ribosyltransferase activity. on the other hand, the activity of enzymes with the substitution at trp18 remained intact. swiss 3t3 cells treated with the enzyme with the trp18 substitution showed the typical ... | 1995 | 7672106 |
| the small gtp-binding protein, rho p21, is involved in bone resorption by regulating cytoskeletal organization in osteoclasts. | rho protein (rho p21), a p21ras-related small guanine nucleotide binding protein, regulates cytoskeletal organization in a number of different types of cells. evidence has indicated that clostridium botulinum-derived adp-ribosyltransferase (c3 exoenzyme) specifically adp-ribosylates rho p21 at asn41 and renders it functionally inactive. in this study, we examined the involvement of rho p21 in osteoclastic bone resorption using the c3 exoenzyme. when osteoclast-like multinucleated cells obtained ... | 1995 | 7673348 |
| inhibition of pma-induced, lfa-1-dependent lymphocyte aggregation by adp ribosylation of the small molecular weight gtp binding protein, rho. | botulinum c3 exoenzyme specifically adp-ribosylates a group of ras-related small molecular weight gtp-binding proteins, rho, and inhibits their biological activity. using this enzyme, we examined the function of rho in pma-induced activation of lymphocyte function-associated antigen-1 (lfa-1) in a b lymphoblastoid cell line, jy. northern blot analysis revealed that among the three rho genes, rhoa mrna was predominantly expressed in jy cells. consistently, only one [32p]adp-ribosylated band was f ... | 1993 | 7680658 |
| genetic interrelationships of saccharolytic clostridium botulinum types b, e and f and related clostridia as revealed by small-subunit rrna gene sequences. | the phylogenetic interrelationships of saccharolytic c. botulinum types b, e and f together with eleven other saccharolytic clostridia were examined by 16s rrna gene sequencing. comparative analysis of the sequence data revealed that the saccharolytic c. botulinum types b, e and f were highly related and represent a single genetic group. strains of c. barati and c. butyricum that produce botulinal neurotoxin revealed almost 100% 16s rrna sequence identity with their respective non-toxigenic coun ... | 1993 | 7682527 |
| direct visualization of botulinum neurotoxin-induced channels in phospholipid vesicles. | the seven botulinum neurotoxin (nt) serotypes produced by strains of clostridium botulinum inhibit neurotransmitter release from synaptic vesicles. neurotoxin is synthesized as a roughly 150k single-chain protein. proteolysis produces two fragments, the 50k l-chain and 100k h-chain, that remain linked by a disulphide bond. intoxication involves membrane attachment by the c-terminal half of the h-chain, endocytotic/lysosomal internalization, vesicle channel formation mediated by the 50k n-termina ... | 1993 | 7689178 |
| [clostridium botulinum in costa rica soils]. | thirty soil samples from the pacific dry forest, the caribbean lowlands and the central plateau of costa rica yielded seven cases with botulinal toxins. of these, five were type c, one a and one b. type c samples were from the dry pacific coastal area, others from the caribbean lowlands. c. botulinum was isolated from three out of seven positive soil samples. the main reason for the poor recovery of c. botulinum from toxigenic samples is attributable to a low concentration of spores in the sampl ... | 1993 | 7701075 |
| from the centers for disease control and prevention. foodborne botulism--oklahoma, 1994. | | 1995 | 7707612 |
| identification of gangliosides as inhibitors of adp-ribosyltransferases of pertussis toxin and exoenzyme c3 from clostridium botulinum. | we have previously reported the presence of an endogenous inhibitory activity in bovine brain for the adp-ribosylation of gtp-binding proteins catalyzed by pertussis toxin (pt) (hara-yokoyama, m., and furuyama, s. (1989) biochem. biophys. res. commun. 160, 67-71). in the present study, we identified the inhibitor as a ganglioside. the screening of various gangliosides revealed that gq1b alpha most effectively inhibited the adp-ribosyltransferase activities of both the holoenzyme and the catalyti ... | 1995 | 7713915 |
| immunological detection of clostridium botulinum toxin type a in therapeutic preparations. | the potent neurotoxins produced by strains of clostridium botulinum act by blocking the release of acetylcholine from peripheral nerve junctions. this specific action of the botulinum neurotoxins is now being exploited therapeutically to treat a variety of conditions involving involuntary muscle spasms. we aimed to develop a sensitive and specific enzyme-linked immunosorbent assay (elisa) which may be used in parallel with the currently accepted mouse bioassay test for the determination of botul ... | 1995 | 7714333 |
| roles of heterotrimeric and monomeric g proteins in sperm-induced activation of mouse eggs. | results of several lines of experimentation suggest that sperm-induced egg activation has several features in common with g protein-coupled receptor signal transduction mechanisms. we report that microinjection of gdp beta s into metaphase ii-arrested mouse eggs blocks sperm-induced egg activation. since gdp beta s inactivates both heterotrimeric and monomeric classes of g proteins, the involvement of members of each of these families in sperm-induced egg activation was evaluated. neither pertus ... | 1994 | 7720569 |