Evaluation of survival of Staphylococcus aureus and Clostridium botulinum in charqui meats

Charqui meats were prepared in laboratory conditions in order to carry out experiments to observe the possibility of development of enterotoxigenic Staphylococcus aureus and Clostridium bottilinum proteolytic type B spores and their toxins. Results demonstrated that the harsh processing conditions, high salt concentration, relative high temperature, a, values, inhibited the growth of both bacteria. Under our experimental conditions, S. aureus would survive throughout the sequence of salting steps i.e. brine followed by rock salting and the sunshine drying step. However, at final a(w) value of 0.70-0.75 would create conditions to inhibit its development. The other experiment revealed that C. botulinum spores germination also was impaired because of these low a(w) values. Under these conditions, charqui meats revealed to be safe products in relation to toxins from both enterotoxigenic S. aureus and C. botulinum. (C) 2003 Elsevier B.V. Ltd. All rights reserved.

Neonatal immune response of Brazilian beef cattle to vaccination with Clostridium botulinum toxoids types C and D by indirect ELISA

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Botulism by Clostridium botulinum type C in goats associated with osteophagia

An outbreak of botulism was detected in goats in the semiarid region of Brazil. In a flock of 460 goats, 38 does were affected and 37 died. Kids and younger goats were not affected. The main clinical signs were flaccid tetraparesis leading to tetraplegia that was often accompanied by twisted neck, tongue paralysis, and muscle tremors. At the time of the visit, 4 out of 11 affected goats were recumbent. Ambulatory goats had uncoordinated and swaying gaits with hypometria and weakness, mainly of the hind limbs. Two recumbent and four ambulatory goats showed twisted neck. Two recumbent goats were euthanized and necropsied. Non-significant gross and histologic lesions were observed. Samples of the liver, gut and rumen content were collected from the two goats and examined for botulinum toxins using the mouse serum neutralization test. The three samples from one goat were positive for type C toxin. Marked osteophagia was observed when the goats had access to bones in the pasture, and the farmer mentioned that osteophagia was common among goats of the flock. A sample of the plant Hybantus ipecaconha, the most abundant forage available for the goats, contained 2800 mg/kg of Ca and 450 mg/kg of P. One soil sample contained 58.12 mg/kg of Ca and 2.02 mg/kg of P. It was concluded that in this outbreak, botulism was associated with osteophagia probably due to phosphorus deficiency. (C) 2012 Elsevier B.V. All rights reserved.

Study of the presence of the spores of Clostridium botulinum in honey in Brazil

The isolation of Clostridium botulinum from honey samples is described. Botulism is characterized as an intoxication provoked by ingestion of contaminated foods with this toxin. Infant botulism happens by the ingestion of spores of C. botulinum together with food that in special conditions of the intestinal tract, such as those present in babies of less than 1 year old, will allow the germination and colonization of the intestine with production and absorption of botulinic toxin. The samples were subjected to dilution and to a thermal shock and cultivated in modified CMM (Difco). Cultures were subjected to Gram smears and toxicity tests in mice. The toxic cultures were purified in RFCA (Oxoid) plates and incubated in anaerobic jars. Positive samples were typed using the mouse assay neutralization test. From the 85 honey samples analyzed, six were positive for C. botulinum (7.06%), and identified as producers of type A, B, and D toxins.

Intoxicação natural por Clostridium botulinum tipo C: em grupo de aves domésticas

Clostridium botulinum causative of toxic infections due to toxin ingestion previously formed, occur in several ingestion species, mainly birds. In a poultry farm, located at São Paulo State, more than 3,000 birds have been attacked by this toxic infections, when the birds showed motionless, loss of weight, accelerated, breathing, resulting in death of the birds. The blood harvest for attainment of the serum and later necropsy was carried out throwgh the following samples: liver, gizzard, crop, feed, water and litter. After that, the toxin was extracted by gelatin-phosphate buffer and inoculation in mice, isolation of the agent in Blood. Ágar and Reinforced Clostridium Ágar and neutralization of toxin determine its type. The inoculation in mice showed positive results in samples of liver, gizzad, crop and symptoms like was waist, and death of the birds by limp paralysis. The colonies that have been isolated, suspected of Clostridium botulinum showed expected results and further analysis revealed positive results to botulinical toxin type C. The farms have to pay attention in the routine jobs, choicer, and elimination of carcass because they are essential to keep this problem away.

Associação de bactérias da família Enterobacteriaceae e Clostridium estertheticum com a deterioração blown pack em cortes cárneos embalados a vácuo

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Resposta sorológica de bovinos vacinados contra o Clostridium chauvoei avaliada pelos testes de aglutinação em placa e Elisa

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Avaliação da nutrição adequada e insuficiente em cobre ou zinco sobre a resposta imune humoral à vacinação contra Clostridium chauvoei e parâmetros hematológicos em bezerros Nelore

Pós-graduação em Medicina Veterinária - FMVZ

Reação em cadeia de polimerase quantitativa para determinação da expressão gênica da neurotoxina de clostridium botulinum tipo A em palmito

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Evaluation of Three Enzyme Immunoassays for Diagnosis of Clostridium difficile-Associated Diarrhea in Foals

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Ocorrência de Clostridium botulinum tipos C e D em criatórios de bovinos no município de Cocalinho, Vale do Araguaia, Mato Grosso

In order to assess the occurrence and distribution of spores and toxins of Clostridium botulinum types C and D in three farms in Cocalinho, at the Araguaia River valley, State of Mato Grosso, Brazil, we analyzed sediment samples from 40 water holes, soil and cattle feces, collected around water holes. Sediments were analyzed by direct method, whilst feces, soil and also sediment samples were individually analyzed by indirect method. The detection of spores and botulinum toxins in the filtered material was performed by bioassay in Swiss Webster mice strain, as well as the serum-neutralization of the positive materials for typing. Samples of cattle feces showed the largest positive rate for C. botulinum, with 25/40 (62.5%), followed by soil, 12/40 (30%), and by sediment, 13/40 (32.5%). From the 40 cattle feces samples, 25 (62.00%) were positive for Clostridium botulinum; six samples were identified as type C, other six as type D, and 13 samples were classified as CD complex. From the equal number (40) of soil samples, 12 (30%) were positive for C. botulinum; two samples were identified as type C, other three as type D, and seven samples were classified as CD complex. Regarding the 40 sediment samples, 13 (32.5%) were positive for C. botulinum; two samples were identified as type C, other three as type D, and eight samples were classified as CD complex. No botulism toxin was detected by indirect method.

Patógenos bacterianos isolados de fezes de felinos domésticos, sem sinais entéricos, de ambiente urbano e rural

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Influence of different shrinking temperatures and vacuum conditions on the ability of psychrotrophic Clostridium to cause 'blown pack' spoilage in chilled vacuum-packaged beef

This study determined the ability of psychrotrophic Clostridium strains isolated from vacuum-packaged beefs and abattoir environments to cause 'blown-pack' spoilage of vacuum-packaged beef stored at 2 and 15 degrees C. The influence of shrinking temperatures (83, 84 and 87 degrees C) and vacuum pressure (6 and 9 mbar) on the occurrence of such spoilage as well as the effects of simulated transportation (500 km) on the integrity of packages was determined. At 15 degrees C and 2 degrees C, twelve and six strains caused 'blown-pack' spoilage, respectively. The combination of vacuum pressure (9 mbar) combined with shrinking temperature (87 degrees C) retarded the occurrence of spoilage. The simulated transportation under the experimental conditions did not affect the integrity of packages. More studies that assess the factors that may contribute for the occurrence of 'blown-pack' spoilage should be performed to avoid the occurrence of such spoilage during its shelf-life. (C) 2012 Elsevier Ltd. All rights reserved.

Identifikation des Gruppe I Introns CDISt1 in offenen Leserastern des Clostridium difficile Genoms und dessen Charakterisierung als chimäres genetisches Element

Im tcdA-Gen des Clostridium difficile Stammes C34 wurde eine Insertion mit einer Größe von 1975 bp lokalisiert. Der als CdISt1 bezeichneten Insertion konnten charakteristische Merkmale von Gruppe I Introns und von Insertionselementen zugewiesen werden. Dem im 5’ Bereich gelegenen Anteil ließen sich die Intron-spezifischen Eigenschaften zuordnen, im 3’ Anteil wurden zwei offene Leseraster gefunden, die hohe Homologien zu Transposasen der IS605 Familie hatten. Funktionelle Analysen belegten die Spleißaktivität des chimären Ribozymes. CdISt1 konnte in mehren Kopien in allen untersuchten C. difficile Stämmen nachgewiesen werden. In anderen clostridialen Spezies konnte das Gruppe I Intron bislang nicht vorgefunden werden. Der Integrationsort in C. difficile war in allen untersuchten Fällen immer ein offenes Leseraster. Bislang waren Gruppe I Introns noch nie in bakteriellen offenen Leserastern beschrieben worden. Es kann angenommen werden, dass der chimäre Aufbau des Ribozymes die Integration in bakterielle offene Leseraster ermöglicht. Dabei wäre für die Spleißaktivität der Gruppe I Intron Anteil maßgeblich, die Mobilität würde über den IS Element Anteil vermittelt. Im Rahmen der Dissertationsarbeit konnten erste experimentelle Hinweise erbracht werden, dass das chimäre Ribozym an der evolution clostridialer Proteine beteiligt sein kann, wovon seinen Wirt C. difficile entsprechend profitieren würde.An insertion of 1975 bp is situated in the tcdA-gene of Clostridium difficile strain C34. The insertion was designated as CdISt1 and it had characteristics of group I introns and insertion elements. The group I characteristcs could be found in the 5’ area of the genetic element, in the 3’ area two open reading frames were located with high homologies to transposases of the IS605 family. Functional studies could proof the splicing activity of the ribozyme. CdISt1 could be found in several copies in all C. difficile strains examined so far. It was absent in other examined clostridial species. In all cases, the integration site in C. difficile was an open reading frame. Up to now, group I introns never were discovered in bacterial open reading frames. It can be assumed that the chimeric characteristics of the ribozyme permit an integration in bacterial open reading frames. The group I intron part would be responsible of the splicing activity, the IS element part could mediate the mobility of the genetic element. First experimental evidences point to a possible involvement of the chimeric ribozyme in the evolution of clostridial proteins, so the host C. difficile could benefit from its presence.

Clostridium difficile: Entdeckung und Charakterisierung der autokatalytischen Prozessierung von Toxin B

Clostridium difficile, der Auslöser der nosokomialen Antibiotika-assoziierten Durchfälle und der Pseudomembranösen Kolitis, besitzt zwei Hauptvirulenzfaktoren: die Toxine A und B. In vorangegangenen Veröffentlichungen wurde gezeigt, dass Toxin B durch einen zytosolischen Faktor der eukaryotischen Zielzelle während des Aufnahmeweges in die Zelle gespalten wird. Nur die N-terminale katalytische Domäne erreicht das Zytosol. Hierbei wurde davon ausgegangen, dass eine Protease der Zielzelle die Spaltung katalysiert. In dieser Arbeit konnte gezeigt werden, dass die Spaltung von Toxin B ein intramolekularer Prozess ist, der zytosolisches Inositolphosphat der Zielzelle als Kofaktor zur Aktivierung der intrinsischen Protease benötigt. Die Freisetzung der katalytischen Domäne durch Inositolphosphat-induzierte Spaltung ist nicht nur das Prinzip des Clostridium difficile Toxin B sondern auch des Toxin A, als auch des alpha Toxin von Clostridium novyi und das Letale Toxin von Clostridium sordellii. Der kovalente Inhibitor von Aspartatproteasen 1,2-epoxy-3-(p-nitrophenoxy)propan (EPNP), wurde dazu verwendet die intrinsische Protease von Toxin B zu blockieren und ermöglichte die Identifikation des katalytischen Zentrums. EPNP modifiziertes Toxin B verliert die intrinsische Proteaseaktivität und Zytotoxizität, aber wenn es direkt in das Zytosol der Wirtszelle injiziert ist, bleibt die Toxizität erhalten. Diese ist damit der erste Bericht eines bakteriellen Toxins, das eukaryotische Signale zur induzierten Autoproteolyse nutzt, um seine katalytisch-toxische Domäne in das Zytosol der Zielzelle freizusetzen. Durch diese Ergebnisse kann das Modell der Toxin-Prozessierung nun um einen weiteren entscheidenden Schritt vervollständigt werden.