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Search Results: 1 - 10 of 298811 matches for " Jürgen;Dutra "
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Sensibilidade toxicológica e especificidade do teste de microfixa??o de complemento na detec??o de toxinas botulínicas C e D em meio de cultura e fígado de camundongos
Menegucci, Edna A.;Dutra, Iveraldo S.;D?bereiner, Jürgen;
Pesquisa Veterinária Brasileira , 1998, DOI: 10.1590/S0100-736X1998000200001
Abstract: the toxicological sensitivity and specificity of the micro-complement fixation test (mcf) for the detection of botulinum toxins c and d were studied in supernatants of the bacterial cultures and in livers of mice inoculated with lethal and sublethal doses. botulinum toxins c and d were produced in hemoline culture medium, titered through the determination of ld50 by the mouse test and adjusted to dilutions of 10, 1, 0.1, 0.01 and 0.001 ld50. two experimental models were used to determine the toxicological sensitivity of mcf in the supernatant of the culture medium with the dilutions described, and also in liver extracts of mice weighing 20 g and inoculated with the same dilutions. detection of the botulinum toxins was attempted in liver extracts of mice which had received lethal doses of the respective toxins, and in others which had been inoculated with sublethal doses and were sacrificed in intervals of 5 days. the results show that the toxicological sensitivity of mcf, regarding the two types of toxins at the level of 0.001 ld50, was 100% when the supernatants of the culture medium were tested; this means that the sensitivity was 100 times higher than with the mouse test. the toxicological sensitivity of mcf in the liver extracts of mice inoculated with 1 and 10 ld50 of botulinum toxins c and d was inferior, giving values of 100, 80, 89 and 72% respectively. by this test it was also possible to detect botulinum toxins type c and d in liver extracts of mice inoculated with sublethal doses, up to 15 days after the injection. the specificity of mcf was 88% and 92%, when liver extracts of healthy control mice were tested and when challenged with antitoxins c and d; and 100% when challenged with the supernatant of the culture medium. these results indicate that mcf could be of importance for research and could substitute in vivo tests.
Botulismo em bovinos de corte e leite alimentados com cama de frango
Dutra, Iveraldo S.;D?bereiner, Jürgen;Souza, Aires M.;
Pesquisa Veterinária Brasileira , 2005, DOI: 10.1590/S0100-736X2005000200009
Abstract: outbreaks of botulism caused by type c and d of the botulinum toxin are frequent in brazil, and are associated with bone chewing and ingestion of contaminated food and water. this paper reports the epidemiological, clinical, pathological and laboratorial aspects of 7 outbreaks of botulism in beef and dairy cattle fed with poultry litter, which occurred in the states of s?o paulo and minas gerais, 1989-2000. five outbreaks occurred in beef cattle herds, raised in confinement or under pasture conditions and supplemented with poultry litter, and 2 outbreaks occurred in dairy farms. from o total of 1,535 cattle supplemented regularily with poultry litter 455 animals (29.64%) died within 2 to 4 weeks. morbidity and mortality varied from 3.47 to 100% in the 7 outbreaks. in one of the farms the lethality was 60.52%, and in others more than 88.43%, reaching 100% in three farms. clinical signs were progressive paralysis, difficulties in moving, decubitus, normal alertness, decreased muscular tonus of tongue and tail, sialorrhoe and dyspnoe. at post-mortem examination of 30 cattle no noteable changes were observed. spores of clostridium botulinum were found in poultry litter samples collected on 7 farms. in liver, ruminal and intestinal fluid samples from 30 necropsied cattle botulinum toxin of type c (5) and d (9) or of the cd complex (1) were found in at least one of the samples collected from 15 animals, which confirms the clincial, pathological and epidemiological diagnosis of botulism.
Sensibilidade toxicológica e especificidade do teste de microfixa o de complemento na detec o de toxinas botulínicas C e D em meio de cultura e fígado de camundongos
Menegucci Edna A.,Dutra Iveraldo S.,D?bereiner Jürgen
Pesquisa Veterinária Brasileira , 1998,
Abstract: No presente estudo pretendeu-se verificar a sensibilidade toxicológica e especificidade do Teste de Microfixa o de Complemento (MCF) na detec o de toxinas botulínicas C e D no sobrenadante de cultivos bacterianos e em fígados de camundongos inoculados com doses letais e subletais. As toxinas foram produzidas em meio de cultura Hemoline, tituladas através da determina o da DL50 pelo Bioensaio em Camundongo e diluídas nas concentra es de 10, 1, 0,1, 0,01 e 0,001 DL50. Desta forma, foram utilizadas em dois modelos experimentais, onde foi determinada a sensibilidade toxicológica do MCF no sobrenadante do meio de cultura com as dilui es descritas acima e ainda em extratos hepáticos de camundongos com peso corporal de 20g, inoculados com as mesmas dilui es. A tentativa de evidencia o das toxinas botulínicas nos extratos hepáticos de camundongos foi realizada através da sua extra o após a morte pela administra o das doses letais e ainda pelo sacrifício dos animais inoculados com doses subletais, em intervalos de 5 dias. Os resultados evidenciaram uma sensibilidade toxicológica para o MCF de 100% para os dois tipos de toxinas ao nível de 0,01 DL50, quando testados os sobrenadantes de meio de cultura, portanto 100 vezes superior ao Bioensaio em Camundongo. A sensibilidade toxicológica do MCF, quando examinados extratos hepáticos de camundongos inoculados com 1 e 10 DL50 de toxinas botulínicas C e D, foi inferior, com valores de 100, 80, 89 e 72%, respectivamente. Pelo teste foi possível detectar toxinas botulínicas tipos C e D nos extratos hepáticos de camundongos inoculados com doses subletais até 15 dias após a sua inocula o. A especificidade do MCF foi de 88 e 92%, quando testados extratos hepáticos de camundongos sadios, e confrontados com as antitoxinas C e D; e 100% no sobrenadante do meio de cultura. Os resultados apontam para uma possível utiliza o do teste como importante instrumento de pesquisa e ainda na eventual substitui o dos testes in vivo pelas suas implica es éticas e limita es práticas.
Modifica??o da microbiota associada às les?es peridentárias da "cara inchada" em bezerros transferidos para área indene
Dutra, Iveraldo S.;Botteon, Rita C.M.;D?bereiner, Jürgen;
Pesquisa Veterinária Brasileira , 2000, DOI: 10.1590/S0100-736X2000000200003
Abstract: observations on the epizootiology of "cara inchada" in cattle (ci) indicated that animals affected by the disease recover spontaneously when they are transferred from the ci-prone area to ci-free pastures. in the presente study 13 young bovines with actively progressing periodontal ci-lesions were transferred to a ci-free area, in order to investigate the clinical course of the disease and the composition of the microflora in the periodontal lesions in two distinct situations: (1) in the actively progressing lesions, and (2) in the healed periodontal pouches of clinically recovered animals. the semi-quantitative and qualitative bacteriological study was undertaken in regard to the percentage of black-pigmented bacteroides in cultures. in the actively progressing lesions of the 13 ci-diseased bovines the percentage of these bacteria was 71.3% in average. the evaluation of the composition of the microflora in the healed periodontal pouches of the clinically recovered bovines showed that bacteria of the black-pigmented bacteroides group existed only at an average of 1.7%. the results of this investigation give further support for the infectious nature of the ci-periodontitis and the primary involvement of these bacteria.
Esporos e toxinas de Clostridium botulinum dos tipos C e D em cacimbas no Vale do Araguaia, Goiás
Souza, Aires M.;Marques, Dercino F.;D?bereiner, Jürgen;Dutra, Iveraldo S.;
Pesquisa Veterinária Brasileira , 2006, DOI: 10.1590/S0100-736X2006000300001
Abstract: the occurrence and distribution of clostridium botulinum spores and toxins type c and d in 300 ponds, used by cattle for drinking on 130 farms located in 12 municipalities of the rio araguaia valley, state of goiás, brazil, was evaluated. the presence of spores was determined indirectly by cultivation in culture medium, followed by inoculation and neutralization in mice of samples of the sediment from the bottom of the raining ponds, from superficial soil and from cattle feces collected to its circuit. the toxin presence was evaluated directly by inoculation in mice of the filtered sediment of the ponds, followed by the neutralization in mice with antitoxins c and d. the presence of c. botulinum spores was significantly more frequent (p<0,05) in the cattle feces (31%), when compared with the results of the superficial soil samples (19%) and the sediments (10%). botulinum toxins of type c and d or classified as belonging to the cd compound were detected in 6 samples (2%) of the 300 ponds. of the 130 worked farms, in 122 (93,85%) ponds clostridium botulinum spores or toxins were found in at least one of the researched variables, whilst ponds on only 8 (6,15%) farms did not present any contamination. age and depth of the ponds were associated with the frequency of detection of botulinum spores and toxins. the older and shallower the ponds were, the larger was the frequency of isolation of the spores and toxins. the contamination of the ponds in the araguaia valley with clostridium botulinum spores and toxins type c and d demonstrates the permanent and growing potential risk for the occurrence of botulism in cattle through drinking water.
Adherence and experimental infection of bacteria associated with periodontal infections of young cattle in Brazil ("Cara inchada")
Grassmann, Barbara;D?bereiner, Jürgen;Dutra, Iveraldo S.;Kopp, Peter A.;Blobel, Hans;
Pesquisa Veterinária Brasileira , 1997, DOI: 10.1590/S0100-736X1997000300006
Abstract: in vitro- and in vivo-assays were conducted, to study the possible role of streptomycin- and actinomycin-producing soil actinomycetes for the pathogenesis of "cara inchada" in cattle (ci). adherence of bacteroides spp. to epithelial cells of the bovine gingiva, known to be associated with the progressive lesions of ci, was significantly increased by the addition of streptomycin, actinomycin or antibiotic culture supernatants of the soil actinomycetes. applications of these mixtures together with actinomyces pyogenes to the marginal gingiva of the upper premolar teeth of about 1 month old holstein friesian calves did not lead to progressive lesions of ci. only one calf exhibited a slight diarrhea and a temporary retraction of the gingiva at the site of application.
Ocorrência e distribui??o de esporos de Clostridium botulinum tipos C e D em áreas de cria??o de búfalos na Baixada Maranhense
Silva, Tania M.D.;Dutra, Iveraldo S.;Castro, Raimundo N.;D?bereiner, Jürgen;
Pesquisa Veterinária Brasileira , 1998, DOI: 10.1590/S0100-736X1998000300007
Abstract: as botulism is a common disease in buffaloes raised in the low lands of the state of maranh?o, brazil, the occurrence of clostridium botulinum spores was evaluated in buffalo breeding areas of 4 municipalities in the "baixada maranhense". twenty eight samples of faeces, mud and soil were collected and divided into 140 subsamples, being 40 of faeces, 65 of mud and 35 of soil. botulinum toxin was detected in the filtrates of 104 cultures (74.28%) from 140 subsamples through the inoculation of mice. using the microcomplement fixation technique for the identification of c. botulinum toxins, type c (14.29%), d (82.14%) and cd complex (3.57%) were found. no significant differences (p>0.05%) between faeces, mud and soil samples were observed. there was a high contamination with c. botulinum spores of the buffalo faeces, mud and soil in the areas studied. identification of other types and subtypes of c. botulinum was not attempted.
"Cara inchada" of cattle, an infectious, apparently soil antibiotics-dependant periodontitis in Brazil
D?bereiner, Jürgen;Dutra, Iveraldo S.;Rosa, Ivan V.;Blobel, Hans;
Pesquisa Veterinária Brasileira , 2000, DOI: 10.1590/S0100-736X2000000200001
Abstract: the objective of this review on the investigation of "cara inchada" in cattle (ci), pursued over the last 30 years, was to elucidate the pathogenicity of the disease and come to proper conclusions on its etiology. ci has been widely considered to be of nutritional origin, caused primarily by mineral deficiency or imbalance. however, the disease consists of a rapidly progressive periodontitis, affecting the periodontal tissues at the level of the premolars and molars during the period of tooth eruption generally starting in young calves. the disease led to great economic losses for farmers in central-western brazil, after the occupation of new land for cattle raising in the 1960s and 1970s. the lateral enlargement of the maxillary bones of affected calves gave the disease the popular name of "cara inchada", i.e., swollen or enlarged face. the enlargement was found to be due to a chronic ossifying periostitis resulting from the purulent alveolitis of ci. black-pigmented non-saccharolytic bacteroides melaninogenicus, always together with actinomyces (corynebacterium) pyogenes, were isolated in large numbers from the periodontal lesions. b. melaninogenicus could be isolated in small numbers also from the marginal gingiva of a few healthy calves maintained on ci-free farms. "in vitro"-assays showed that streptomycin and actinomycin, as well as the supernatants of cultivates of actinomycetes from soils of ci-prone farms, applied in subinhibitory concentrations to the bacteria tested, enhanced significantly (up to 10 times) the adherence of the black-pigmented b.melaninogenicus to epithelial cells of the bovine gingiva. the antibiotics are apparently produced in large quantities by the increased number of soil actinomycetes, including the genus streptomyces, that develop when soil microflora are modified by cultivating virgin forest or "cerrado" (tree-savanna) for the first time for cattle grazing. the epidemiology of ci now provides strong evidence that the ingestion with
A etiologia da "cara inchada", uma periodontite epizoótica dos bovinos
D?bereiner, Jürgen;Dutra, Iveraldo dos Santos;Rosa, Ivan Valad?o;
Pesquisa Veterinária Brasileira , 2004, DOI: 10.1590/S0100-736X2004000100011
Abstract: a condensed version in portuguese of an extensive review on "cara inchada"-periodontitis of cattle, published in english, is presented with some additional information. this disease was responsible for severe losses of young cattle especially in the 1970's and 1980's in central brazil. due to the progressive periodontitis and the loss of teeth, the animals cannot eat properly, loose condition and may die. this was believed to be due to mineral deficiency or imbalance. however, field and laboratory observations and experiments over 30 years showed that it is a multifactorial infectious disease which can be defined as bovine epizootic periodontitis. it was concluded that there are three main factors required for its development: (1) cattle affected are at the age when premolar and molar teeth erupt; (2) bacteria of the bacteroides group are present in the subgingival spaces; (3) the ingestion with the forage of subinibitory concentrations of antibiotics, mainly streptomycin, produced by the large increase in the number of actinomycetes found in soils from pastures sown after recently cleared forest; this leads to an increased adherence of bacteroides spp to the gingival epithelium and to the progressive destruction of the periodontal tissues. nowadays, the disease has practically disappeared, because the disturbed soil microflora has reached the new equilibrium, and the occupation of virgin land for cattle raising has almost ceased. new outbreaks may occur with former problem-pastures when these are freshly cultivated as this again leads to a disequilibrium of the soil microflora and to increased antibiotic production. other antibiotics such as spiramycin and virginiamycin, administered orally or added to a mineral supplement, can control the disease.
"Cara inchada" of cattle, an infectious, apparently soil antibiotics-dependant periodontitis in Brazil
D?bereiner Jürgen,Dutra Iveraldo S.,Rosa Ivan V.,Blobel Hans
Pesquisa Veterinária Brasileira , 2000,
Abstract: The objective of this review on the investigation of "cara inchada" in cattle (CI), pursued over the last 30 years, was to elucidate the pathogenicity of the disease and come to proper conclusions on its etiology. CI has been widely considered to be of nutritional origin, caused primarily by mineral deficiency or imbalance. However, the disease consists of a rapidly progressive periodontitis, affecting the periodontal tissues at the level of the premolars and molars during the period of tooth eruption generally starting in young calves. The disease led to great economic losses for farmers in central-western Brazil, after the occupation of new land for cattle raising in the 1960s and 1970s. The lateral enlargement of the maxillary bones of affected calves gave the disease the popular name of "cara inchada", i.e., swollen or enlarged face. The enlargement was found to be due to a chronic ossifying periostitis resulting from the purulent alveolitis of CI. Black-pigmented non-saccharolytic Bacteroides melaninogenicus, always together with Actinomyces (Corynebacterium) pyogenes, were isolated in large numbers from the periodontal lesions. B. melaninogenicus could be isolated in small numbers also from the marginal gingiva of a few healthy calves maintained on CI-free farms. "In vitro"-assays showed that streptomycin and actinomycin, as well as the supernatants of cultivates of actinomycetes from soils of CI-prone farms, applied in subinhibitory concentrations to the bacteria tested, enhanced significantly (up to 10 times) the adherence of the black-pigmented B.melaninogenicus to epithelial cells of the bovine gingiva. The antibiotics are apparently produced in large quantities by the increased number of soil actinomycetes, including the genus Streptomyces, that develop when soil microflora are modified by cultivating virgin forest or "Cerrado" (tree-savanna) for the first time for cattle grazing. The epidemiology of CI now provides strong evidence that the ingestion with the forage of such antibiotics could possibly be an important determinant factor for the onset and development of this infectious periodontitis. The antibiotic enhanced adherence of B.melaninogenicus to the sulcus-epithelium of the marginal gingiva, is thought to allow it to colonize, form a plaque and become pathogenic. There is experimental evidence that this determinant factor for the development of the periodontitis is present also in the milk of the mothers of CI-diseased calves. It has been shown that the bacteria isolated from the periodontal CI-lesions produce enzymes and endotoxins c
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