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Dengue virus (DENV) is a global health problem. Severe dengue can manifest with hemorrhage and signs of organ dysfunction, including the kidneys. The innate immune system is an important barrier against arbovirus infection and, specifically in dengue, the cytokines IL1ß and IL18 and caspase-1 activation make up a set of host immune strategies. Cell death mechanisms include pyroptosis, necroptosis and autophagy, each with peculiar markers: gasdermin, RIPK3/MLKL, LC3, respectively. In DENV infection, necrosis and apoptosis are involved and, when infecting monocytes and macrophages in vitro, DENV is capable of inducing pyroptosis. Our objective was to explore the presence of markers of necroptosis, pyroptosis and autophagy in renal lesions caused by DENV. MATERIAL AND METHODS: twenty specimens of lesions from patients who died due to DENV infection, from the pathology department of Hospital Guilherme Álvaro, Santos, SP, were subjected to histological and immunohistochemical studies. Histological sections were stained with hematoxylin-eosin to evaluate tissue changes or collected for research with antibodies: anti-DENV (Instituto Evandro Chagas-PA), RIPK3 (NBP2-45592), MLKL (ab184718), gasdermin D (#36425), LC3 (14600-AP), caspase 1 (#98033), IL1ß (AF201-NA) and IL18 (SC6178). Semi-quantitative analysis was performed on 20 glomeruli and evaluation on tubules and mononuclear cells. This study was approved by the ethics committee of the USP Faculty of Medicine. RESULTS: histological analysis demonstrated glomerular congestion, glomerulitis (medium to severe), acute kidney injury and hyalinization of the glomeruli. Viral antigens were visualized on mononuclear cells. LC3 (autophagy) expression ranged from moderate to intense (++/+++) in glomeruli, tubules and mononuclear cells. The expression of gasdermin (pyroptosis) was mild (+) in most cases in the glomeruli and moderate (++) in the tubules. RIPK3 and MLKL (necroptosis) mild in tubules and mononuclear cells (+). The expression of the cytokines IL1ß and IL18 and caspase 1 was moderate (++). Statistical analysis showed greater expression of LC3 over the others. CONCLUSIONS: Our results contribute to the understanding of the pathogenesis of renal involvement in severe dengue, considering the likely anti-viral mechanism of autophagy. To a lesser extent, pyroptosis is also present, corroborating previous data.

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Patients undergoing chemotherapy with cisplatin commonly present gastrointestinal effects such as constipation and gastric emptying (GE) delay. Both the purinergic system and physical exercise modulate the gastrointestinal (GI) tract. In the current study, we investigated the role of ATP, physical exercise, and P2X7 receptor blocking on GE delay induced by cisplatin in rats. Male rats were divided into the following groups: control (C), cisplatin (Cis), exercise (Ex), Brilliant Blue G (BBG), ATP, Cis+Ex, Cis+ATP, Cis+BBG, Cis+Ex+BBG, Cis+Ex+BBG+ATP, and Cis+ATP+BBG. GE delay was induced by treatment with 1 mg/kg cisplatin (1 time/week for 5 weeks, ip). The moderate physical exercise was swimming (1 h/day, 5 days/week for 5 weeks). At the end of the treatment or exercise and 30 min before the GE assessment, some groups received BBG (50 mg/kg, sc) or ATP (2 mg/kg, sc). Then, GE was assessed after a 10-min postprandial period. Chronic use of Cis decreased GE delay (P<0.05) compared to the control group. Both exercise and ATP prevented (P<0.05) GE delay compared to Cis. The pretreatment with BBG significantly inhibited (P<0.05) the effect of exercise and ATP. On the other hand, the association between exercise and ATP reversed (P<0.05) the effect of the BBG and prevented GE delay. Therefore, we suggest that both exercise and treatment with ATP activate P2X7 receptors and prevent GE delay induced by cisplatin in rats.

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S1P (sphingosine 1-phosphate) receptor modulator (SRM) drugs interfere with lymphocyte trafficking by downregulating lymphocyte S1P receptors. While the immunosuppressive activity of SRM drugs has proved useful in treating autoimmune diseases such as multiple sclerosis, that drug class is beset by on-target liabilities such as initial dose bradycardia. The S1P that binds to cell surface lymphocyte S1P receptors is provided by S1P transporters. Mice born deficient in one of these, spinster homolog 2 (Spns2), are lymphocytopenic and have low lymph S1P concentrations. Such observations suggest that inhibition of Spns2-mediated S1P transport might provide another therapeutically beneficial method to modulate immune cell positioning. We report here results using a novel S1P transport blocker (STB), SLF80821178, to investigate the consequences of S1P transport inhibition in rodents. We found that SLF80821178 is efficacious in a multiple sclerosis model but - unlike the SRM fingolimod - neither decreases heart rate nor compromises lung endothelial barrier function. Notably, although Spns2 null mice have a sensorineural hearing defect, mice treated chronically with SLF80821178 have normal hearing acuity. STBs such as SLF80821178 evoke a dose-dependent decrease in peripheral blood lymphocyte counts, which affords a reliable pharmacodynamic marker of target engagement. However, the maximal reduction in circulating lymphocyte counts in response to SLF80821178 is substantially less than the response to SRMs such as fingolimod (50% vs. 90%) due to a lesser effect on T lymphocyte sub-populations by SLF80821178. Finally, in contrast to results obtained with Spns2 deficient mice, lymph S1P concentrations were not significantly changed in response to administration of STBs at doses that evoke maximal lymphopenia, which indicates that current understanding of the mechanism of action of S1P transport inhibitors is incomplete.

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Patients undergoing chemotherapy with cisplatin commonly present gastrointestinal effects such as constipation and gastric emptying (GE) delay. Both the purinergic system and physical exercise modulate the gastrointestinal (GI) tract. In the current study, we investigated the role of ATP, physical exercise, and P2X7 receptor blocking on GE delay induced by cisplatin in rats. Male rats were divided into the following groups: control (C), cisplatin (Cis), exercise (Ex), Brilliant Blue G (BBG), ATP, Cis+Ex, Cis+ATP, Cis+BBG, Cis+Ex+BBG, Cis+Ex+BBG+ATP, and Cis+ATP+BBG. GE delay was induced by treatment with 1 mg/kg cisplatin (1 time/week for 5 weeks, ip). The moderate physical exercise was swimming (1 h/day, 5 days/week for 5 weeks). At the end of the treatment or exercise and 30 min before the GE assessment, some groups received BBG (50 mg/kg, sc) or ATP (2 mg/kg, sc). Then, GE was assessed after a 10-min postprandial period. Chronic use of Cis decreased GE delay (P<0.05) compared to the control group. Both exercise and ATP prevented (P<0.05) GE delay compared to Cis. The pretreatment with BBG significantly inhibited (P<0.05) the effect of exercise and ATP. On the other hand, the association between exercise and ATP reversed (P<0.05) the effect of the BBG and prevented GE delay. Therefore, we suggest that both exercise and treatment with ATP activate P2X7 receptors and prevent GE delay induced by cisplatin in rats.

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Reproductive performance is known to differ between co-sexual and non-co-sexual species. Thus, our aim was to determine whether: (i) the distance between sex structures is negatively associated with sex expression; (ii) male gametangia take longer to mature in rhizautoicous species than in gonioautoicous species; and (iii) the gonioautoicous sexual system has greater reproductive success (i.e. percentage of ramets with sporophyte) than the rhizautoicous sexual system. One population each of the mosses Fissidens scariosus and F. submarginatus, rhizautoicous and gonioautoicous, respectively, in a remnant of Atlantic Forest in Brazil were sampled monthly from September 2016 until August 2017. The number and phenophases of antheridia, archegonia and sporophytes were analysed for each species. Sexual expression and reproductive success were calculated, and reproductive phenology compared across environmental variables. As expected, sexual expression was significantly higher for the gonioautoicous species, which produced antheridia throughout the year and archegonia over many months, while gametangia production by the rhizautoicous species occurred only during the rainy season. Mean number of gametangia per perigonium and perichaetium were slightly higher for the rhizautoicous species (6.84 antheridia; 11.38 archegonia) than for the gonioautoicous species (4.39; 7.62). Gametangia and sporophyte production in the rhizautoicous species were markedly seasonal compared to that of the gonioautoicous species, although reproductive success did not differ. Therefore, we infer that the rhizautoicy (i.e. a functional dioicy) promotes lower expression of gametangia compared to gonioautoicy but is more efficient and so obtains the same reproductive success.

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Para avaliar as condições higiênico-sanitárias e tecnológicas (HST) de produção e comercialização da carne de sol no município de Salinas, na região Norte do estado de Minas Gerais, foram coletadas 40 amostras no comércio local para a realização de análises físico-químicas e microbiológicas. A carne de sol é produzida artesanalmente em estabelecimentos comerciais e considerada uma tradição da região. Nas análises físico-químicas de umidade, proteína, gordura, cinzas, cloretos e pH, foram encontrados valores médios de 70,13%, 22,35%, 2,25%, 5,09%, 3,63% e 5,8, respectivamente. Duas amostras (5%) foram positivas para Salmonella spp. e 16 (40%) apresentaram contagens de S. aureus superiores a 103UFC/g. Os valores encontrados nas análises de mesófilos aeróbicos, bolores e leveduras e coliformes totais e termotolerantes foram de 2,50x107 UFC/g, 1,73x104 UFC/g, 9,1NMP/g e 4,3NMP/g, respectivamente. A carne de sol produzida em Salinas é um produto artesanal, portanto heterogêneo quanto às características de produção, comercialização e de qualidade microbiológica e físico-química. A importância socioeconômica da carne de sol na região é considerável, o que justifica a necessidade de se conhecer melhor suas características para auxiliar no desenvolvimento de eventuais políticas públicas regionais visando ao controle sanitário desse produto.(AU)

In order to evaluate the hygienic-sanitary and technological conditions (HST) of production and commercialization of sun-dried meat, in the city of Salinas, in the North of Minas Gerais, 40 samples of the product were collected in the local commerce for carrying out physicochemical and microbiological analyses. The sun-dried meat is produced in the commercial establishments and considered a tradition of the region. In the physicochemical analyzes of moisture, protein, fat, ash content, chlorides and pH were found values of 70.13%, 22.35%, 2.25%, 5.09%, 3.63% and 5.8, respectively. Two samples (5%) were positive for Salmonella spp. and 16 (40%) had Staphylococcus aureus counts higher than 10 3 CFU/g. The values found for the analyses of aerobic mesophilic microorganisms, yeasts and molds and total and thermotolerant coliforms were 2.50 x 10 7 CFU/g, 1.73 x 10 4 CFU/g, 9.1MPN/g and 4.3MPN/g, respectively. The sun-dried meat from Salinas is a handmade product, therefore heterogeneous in terms of production, and physicochemical and microbiological quality. The socioeconomic importance of the sun-dried-meat in the region is considerable, which justifies the need to know its characteristics better to help in the development of regional public policies aiming at sanitary control of the product.(AU)

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Com o objetivo de avaliar a situação epidemiológica da cisticercose suína e bovina na zona rural de cinco municípios, distribuídos em três distintas regiões do estado de Minas Gerais, foi determinada a prevalência das cisticercoses bovina e suína nas propriedades rurais e os principais fatores de risco que poderiam favorecer a transmissão e manutenção da doença nas referidas propriedades. A pesquisa abrangeu 388 propriedades, localizadas em 91 diferentes comunidades rurais, sendo coletadas 1.792 amostras de sangue bovino e 554 de suíno. Além da avaliação das referidas amostras laboratoriais (ELISA indireto e imunoblot), também foram analisados os dados obtidos da aplicação de um questionário para cada propriedade, no qual constava as informações sobre as condições socioeconômicas, higiênico-sanitárias e as relacionadas ao sistema de criação animal. A prevalência da cisticercose variou de 0,3 a 5,9% nos bovinos e de 0 a 2,8% nos suínos criados artesanalmente nesses municípios pesquisados. Os principais fatores de risco de transmissão identificados foram a fonte de água consumida, a origem da carne, a natureza do município e da região, para a cisticercose bovina, e o destino do esgoto e o sistema de criação, para a cisticercose suína.(AU)

In order to evaluate the epidemiological situation of porcine and bovine cysticercosis in the rural area of five municipalities, distributed in three different regions of the state of Minas Gerais, Brazil, the prevalence of bovine and porcine cysticercosis was determined in the rural properties as well as the main risk factors that may favor the transmission and maintenance of the disease in these properties. The research covered 388 farms, located in 91 different rural communities, with 1,792 samples of bovine blood and 554 of swine collected. In addition to the evaluation of these laboratory samples (indirect ELISA and Imunoblot), the data obtained from the application of a questionnaire for each property were also analyzed, with information on socioeconomic, hygienic-sanitary and animal-related conditions. The prevalence of cysticercosis ranged from 0.3 to 5.9% in cattle and from 0 to 2.8% in the pigs raised in these municipalities. Among the main risk factors for transmission of bovine cysticercosis were the source of water consumed, the origin of the meat, the nature of the municipality and the region. Regarding the pigs, risk factors were the sewage disposal and animal management system.(AU)

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The clinical manifestation and course of Leishmania infections depend on factors such as species, virulence and host-immunity. Although trypanosomatids are considered to have clonal propagation, genetic hybridization has produced successful natural hybrid lineages. Hybrids displaying strong selective advantages may have an impact on pathogenesis and the eco-epidemiology of leishmaniasis. Thus, characterization of phenotypic properties of Leishmania hybrids could bring significant insight into the biology, infectivity, pathogenicity and transmission dynamics of these atypical strains. The present study focuses on phenotypic features and survival capacity of Leishmania infantum/Leishmania major hybrid isolates as compared with representative putative parental species, L. infantum and L. major. In vitro assays (growth kinetics, susceptibility to different conditions) and in vivo infection (parasite detection and histopathological alterations) showed that hybrids present higher growth capacity and decreased susceptibility to reactive oxygen species. Furthermore, evaluation of infected spleen tissue suggests that hybrids induce a stronger immune reaction than their putative parents, leading to the development of white pulp hyperplasia in B-lymphocyte compartments. Overall, these hybrids have shown high plasticity in terms of their general behaviour within the different phenotypic parameters, suggesting that they might have acquired genetic features conferring different mechanisms to evade host cells.

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IgA nephropathy (IgAN) is th e commonest primary glomerular disease worldwide. Studies on its prevalence in Brazil are however scarce. Databases and clinical records from 10 reference centres were retrospectively reviewed. Clinical and laboratory features at the moment of the biopsy were retrieved (age, gender, presence of hematuria, serum creatinine [mg/dL], proteinuria [g/24 h]). Renal biopsy findings were classified according to Haas single grade classification scheme and the Oxford Classification of IgAN. 600 cases of IgAN were identified, of which 568 (94.7 %) were on native kidneys. Male to female ratio was 1.24:1. Patients averaged 32.76 ± 15.12 years old (range 4-89, median 32). Proteinuria and hematuria were observed, respectively in 56.63 and 72.29 % of patients. The association of both these findings occurred in 37.95 % of the cases. Serum creatinine averaged 1.65 ± 0.67 mg/dL (median 1.5 mg/dL) at diagnosis. Segmental sclerosis and mesangial hypercellularity were the main glomerular findings (47.6 and 46.2 %) The commonest combination by Oxford Classification of IgAN, was M0 E0 S0 T0 (22.4 %). Chronic tubulo-interstitial lesions with an extension wider than 25 % of the renal cortex could be identified in 32.2 % of the cases. Tubular atrophy and interstitial fibrosis were more strongly associated with higher 24-h proteinuria and serum creatinine levels. Segmental sclerosis (S1) showed a stronger tendency of association with the presence of tubulo-interstitial lesions (T1 and T2) than other glomerular variables. To the best of our knowledge this is the largest series of IgAN in Brazil. It depicts the main biopsy findings and their possible clinical correlates. Our set of data is comparable to previous reports.

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Com o objetivo de diagnosticar a situação do complexo teníase-cisticercose bovina em Minas Gerais, Brasil, foi selecionado o município de São João Evangelista, onde foram coletadas amostras de sangue de 339 bovinos em 15 propriedades rurais, sorteadas aleatoriamente. Em cada propriedade, foi aplicado um questionário socioeconômico para a análise de fatores que favorecem a manutenção do complexo teníase-cisticercose bovina. Foi realizado também o diagnóstico de teníase humana por meio de exame coproparasitológico dos habitantes das propriedades. Encontrou-se a prevalência de 4,1% para cisticercose bovina e a frequência de 2,94% para teníase humana. Entre os fatores de risco para a manutenção do complexo teníase-cisticercose analisados, foi observada uma relação estatisticamente significativa (P=0,042) entre a ocorrência de cisticercose bovina e a ingestão de carne malpassada pelos entrevistados. Concluiu-se que a cisticercose bovina está presente no município de São João Evangelista, MG, em índices considerados endêmicos, sendo o consumo de carne malpassada e não inspecionada o principal fator de risco para a manutenção do complexo teníase-cisticercose, o que reforça a necessidade da adoção de medidas de controle com contínua vigilância epidemiológica e sanitária.

In order to diagnose the situation of bovine taeniasis-cysticercosis complex in the state of Minas Gerais, Brazil, the city of São João Evangelista was selected, and blood samples were collected from 339 cattle in 15 randomly selected farms. A socioeconomic questionnaire was filled in each property for the analysis of the factors that favor the maintenance of the taeniasis-cysticercosis complex. Additionally, there was the diagnosis of human taeniasis verified by stool examinations of the properties' inhabitants. A prevalence of 4.1% for bovine cysticercosis and the frequency of 2.94% for human taeniasis were found. Among the risk factors, a statistically significant relation (p = 0.042) was found between the occurrence of bovine cysticercosis and the ingestion of undercooked meat. It was concluded that bovine cysticercosis is broadly distributed in the city of São João Evangelista, with rates considered endemic, being the consumption of raw and not-inspected meat the main risk factors for the maintenance of complex taeniasis-cysticercosis, reinforcing the need to adopt control measures with continuous epidemiological and health surveillance.

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The role of CD25+ regulatory T cells during the course of Trypanosoma cruzi infection has been previously analyzed, and the bulk of results have shown a limited role for this T cell subpopulation. In this study, we have used an IgM, nondepleting monoclonal antibody (mAb) aiming at blocking interleukin (IL)-2 activity on CD25+ T cells. The administration of this antibody 10 days before infection increased the resistance of outbred Swiss mice to the Colombian strain of T. cruzi. Anti-CD25-treated mice had lower parasitemia and augmented numbers of effector memory T cells. In addition, these animals showed higher numbers of splenic T cells secreting IFN-γ and TNF-α, both cytokines described to be involved in the resistance to T. cruzi infection. The same treatment also increased the numbers of splenic T cells that produced homeostatic and regulatory cytokines, such as IL-2 and IL-10, and CD4+CD25+ T cells. The administration of nondepleting anti-CD25 mAb at the beginning of the chronic phase, when parasites were cleared from the blood, halted the inflammatory process in the heart, without any signs of infection reactivation. These results indicate that nondepleting anti-CD25 monoclonal antibodies may be useful to treat chronic Chagas' disease.

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This work aimed at investigating the lipid profile of zoonotic visceral leishmaniasis (VL) patients' sera and the effect of lipoproteins on the in vitro production of tumour necrosis factor-alpha (TNF-alpha), interleukin (IL)-6, IL-10 and IL-12 by Leishmania infantum-infected and uninfected macrophages. Lipids were quantified in 26 VL patients' sera and 26 healthy controls from a VL endemic area. The patients' sera had higher triglyceride and very low density lipoprotein (VLDL) levels, and much lower apolipoprotein A1, total cholesterol, low density lipoprotein (LDL) and high density lipoprotein (HDL) levels than the control sera. Lipoprotein fractions were obtained by ultracentrifugation of sera. The addition of LDL and HDL to Leishmania-infected and uninfected macrophages, in physiological concentrations, enhanced the production of IL-6 and IL-10, but not of IL-12. LDL stimulated the production of TNF-alpha only in infected macrophages, whereas HDL stimulated the production of lower amounts of TNF-alpha in both infected and uninfected macrophages. VLDL stimulated only the production of IL-10. It is proposed herein that LDL may influence the development of VL by promoting the production of TNF-alpha by infected macrophages. A decrease in plasma LDL in some VL patients (to 20 mg/mL or less); however, would tend to reduce the production of TNF-alpha and therefore to limit the development of immune-mediated pathology, not withstanding the fact that it would perhaps increase the permissiveness of macrophages to Leishmania growth.

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Realizaram-se inspeção visual e avaliações bacteriológicas e físico-químicas da piramutaba, Brachyplatistoma vaillanti, congelada, eviscerada e sem cabeça, de 20 amostras compostas por um pool de três peixes dos dois principais distribuidores da região de Belo Horizonte, MG, sob as exigências legais. Salmonella ssp. e Staphylococcus aureus foram encontradas somente em amostras de um distribuidor, indicando que 10 por cento delas estavam impróprias para o consumo humano. Os resultados confirmam a baixa incidência desses patógenos na piramutaba. As bases voláteis totais estiveram dentro do limite exigido por lei, e os valores de pH apresentaram-se fora dos padrões legais em 90 por cento das amostras, nos dois distribuidores.

Visual inspection and bacteriological and physico-chemical evaluations were carried out in frozen, eviscerated, and headless piramutaba (Brachyplatistoma vaillanti). Twenty samples composed by a pool of three fish from the two main wholesalers of Belo Horizonte, MG, were studied. Salmonella ssp. and Staphylococcus aureus were only found in samples of one wholesaler, representing that 10 percent of the samples were inappropriate for human consumption. The results confirmed the low incidence of these pathogens in piramutaba. The total volatile bases were in accordance and the pH values were not in accordance with the law requirements in 90 percent of the samples.

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The aim of this study was to identify splenic immuno-inflammatory patterns associated with natural infection by Leishmania chagasi. Spleen samples were obtained from 72 stray dogs from an endemic area of visceral leishmaniasis. The animals were grouped into four categories as follows: (i) potentially resistant to visceral leishmaniasis, with a positive leishmanin skin test result, and negative splenic culture for Leishmania parasites (ii) potentially susceptible to visceral leishmaniasis, with a negative leishmanin skin test and positive splenic culture for Leishmania (iii) infected with undefined susceptibility status, with a positive leishmanin skin test and positive splenic culture for Leishmania, and (iv) noninfected, with a negative leishmanin skin test, negative splenic culture for Leishmania, and negative serology for anti-Leishmania antibodies. Histopathological analyses showed that there was a higher frequency of perisplenitis (18/25, P < 0.0001), granuloma (7/25, P = 0.0102), structural disorganization (14/25, P < 0.0001), and atrophy of the lymphoid follicles (20/25, P = 0.0036) and of the marginal zone (15/25, P = 0.0025) in the potentially susceptible group than in the other groups. The data presented here show changes in the white pulp of the spleen that are associated with naturally acquired visceral leishmaniasis.

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Associations among parameters commonly used as markers of infection by Leishmania sp., or of susceptibility to visceral leishmaniasis, were investigated in 325 stray dogs from an area where this disease is endemic. Evidence of infection (presence of Leishmania in splenic cultures, positive leishmanin skin test (LST) or detection of anti-Leishmania antibody activity in the serum) was found in 57% of the animals. Both evidence of weight loss (chi(2)-test, P=0.0005) and presence of specific antibody activity in the serum (chi(2)-test, P<0.0001) were directly associated with positive splenic culture. The frequencies of animals with positive splenic culture were directly correlated with the intensities of antibody activity in the serum as measured by ELISA (relative risk of 3.4 for animals with moderate antibody levels and relative risk of 8.43 for animals with high-antibody levels). A negative association was observed between positive leishmanin skin test results and emaciation (chi(2), P=0.0089). Furthermore, animals with positive splenic cultures and negative leishmanin skin test results had higher levels of total serum IgG (Kruskal-Wallis test, P=0.001) and IgG2 (Kruskal-Wallis test, P=0.05) than animals with negative splenic cultures, and were more emaciated than animals with negative LST results and positive splenic cultures. The data presented herein suggest that associating these common parameters may improve their performance in predicting susceptibility to canine visceral leishmaniasis.

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Foram avaliados alguns parâmetros inerentes ao ELISA, por meio de ensaios de reatividade de soros-controle positivos e negativos para a cisticercose bovina com relação a três tipos de antígenos de larva de Taenia solium: total, de escólex e de membrana. As concentrações de antígeno de 0,25; 0,5; 1; 2 e 4µg por orifício, e as diluições de soro de 1:25, 1:50, 1:100 e 1:200, foram os parâmetros que menos influenciaram no desempenho do teste. A substância bloqueadora, o leite desnatado e as diluições de conjugado, 1:1.250, 1:2.500 e 1:5.000, representaram os melhores indicadores de desempenho do teste. Concluiu-se que essa combinação de critérios deve ser considerada no diagnóstico da cisticercose bovina, em atividades de rotina ou de padronização do referido teste, considerando os três antígenos de larva de T. solium estudados.

Some parameters of ELISA were evaluated using positive and negative bovine sera for cysticercosis and three types of antigens of Taenia solium larvae: total, scolex and membrane. The antigen concentrations (0.25; 0.5; 1; 2 and 4µg/well) and the serum dilutions (1:25, 1:50, 1:100 and 1:200) were the parameters that influenced less the test performance; while blocking substance, skimmed milk, and conjugate dilutions, 1:1.250, 1:2.500 and 1:5.000 were the best indexes of the test performance. It was concluded that this combination of criteria should be considered in the diagnosis of bovine cysticercosis, in routine diagnosis and for the ELISA test standardization.

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Avaliaram-se os efeitos de cinco períodos (quatro, oito, 12, 14 e 16 horas) de jejum pré-abate sobre a perda de peso e rendimento de carcaça e cortes de frangos de corte. Foram utilizados 240 frangos (120 machos e 120 fêmeas), linhagem Cobb, criados até 44 dias de idade. No 44° dia, as aves foram separadas de acordo com o período de jejum (tratamentos) e o sexo, cada tratamento com 24 repetições. Nos tratamentos de quatro, oito, 12 e 16 horas, o jejum foi alimentar e no tratamento de 14 horas, o jejum foi alimentar e hídrico. O teste utilizado para as análises das médias foi o SNK (Student-Newman-Keuls). Foram analisadas as seguintes variáveis: perda de peso vivo após o jejum, taxa de absorção de água pela carcaça, rendimentos da carcaça inteira e dos cortes comerciais coxa e sobrecoxa, peito, dorso, asa, pés e cabeça e pescoço, rendimentos da moela e fígado e peso dos intestinos. Os períodos de jejum de oito, 12, 14, e 16 horas apresentaram maior rendimento de carcaça, sendo superiores ao período de quatro horas de jejum (P<0,05). O tratamento de quatro horas de jejum apresentou maior rendimento de fígado e peso de intestino em relação aos demais tratamentos (P<0,05). O período de jejum não influenciou a taxa de absorção de água nem o peso de moela (P>0,05). As fêmeas absorveram mais água do que os machos, e apresentaram rendimentos de carcaça e cortes comerciais superiores aos dos machos (P<0,05).

This experiment was designed in order to evaluate the effect of five intervals of pre-slaughter fasting (four, eight, 12, 14 and 16 hours) on weight loss, carcass yielding and poultry cuts yielding of broiler chickens. A total of 120 males and 120 females broiler chickens of Cobb lineage were raised during 44 days. On the 44th day, chickens were grouped according to their fasting period (treatments) and gender. Each treatment was composed of 24 repetitions. Animals of the of four, eight, 12 and 16 hours treatments were not fed ration while animals of the 14 hours fasting treatment were not fed ration or water. The statistical test used for mean comparison was SNK (Student-Newman-Keuls). The following variables were analyzed: loss of live weight, rate of water absorbed by carcass; whole carcass and commercial cuts (legs and forelegs, chest, dorsum, wings, feet and head and neck) yielding; gizzard and liver yielding as well as intestinal weight. The fasting periods of eight 12, 14 and 16 hours showed greater carcass yielding (P<0.05) being higher than those from the four hours fasting period. The four hours fasting group showed the highest yielding of liver and intestinal weight in relation to the other groups (P<0.05). The fasting period did not influence the rate of water absorption or the gizzard weight (P>0.05). Females retained more water than males and showed higher carcass and commercial cuts yielding than males (P<0.05).

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Quatro cepas de Lactobacillus spp. e duas cepas de Lactococcus spp. isoladas de queijos de coalho artesanal e industrial foram testadas quanto às suas atividades antimicrobianas. Observou-se atividade antagonista dessas bactérias ácido-lácticas frente a elas, a outras bactérias ácido-lácticas isoladas de queijo de coalho, aos patógenos isolados dos mesmos queijos e a cepas de patógenos de referência. Verificou-se diferença (P<0,05) entre as atividades antagonistas, exceto quando as próprias bactérias ácido-lácticas foram utilizadas como reveladoras. Lactobacillus spp. apresentaram as atividades antagonistas mais potentes.

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A prevalência da tuberculose em bovinos abatidos em Minas Gerais, de 1993 a 1997, em 10 matadouros sujeitos à Inspeção Federal, foi de 0,7ë. Os bovinos procederam principalmente deste Estado (74 por cento) e de Goiás (25 por cento). A prevalência variou, temporal e espacialmente, entre zero e 8,7ë e é idêntica à de outros levantamentos parciais feitos no Brasil desde 1924. Contribuíram para ela o local de abate e o perfil dos bovinos abatidos. Em Minas Gerais foi de 0,8ë e em Goiás 0,4ë. A tuberculose foi diagnosticada em 90 municípios de Minas Gerais e em 17 de Goiás, correspondendo a 16,8 por cento e 12,7 por cento dos municípios mineiros e goianos, respectivamente. A prevalência da tuberculose em Minas Gerais foi maior nos bovinos abatidos na Região Sudoeste (1,7 por cento).

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RESUMEN

Isolaram-se 192 cepas de bactérias lácticas de cinco amostras de queijo-de-minas artesanal, oriundos da regiäo do Serro, MG. Os resultados da prova de inibiçäo direta indicaram que 48 cepas isoladas (25 por cento) foram capazes de inibir o crescimento in vitro de microrganismos indicadores, dentre os quais Staphylococcus aureus e Listeria monocytogenes. As 48 cepas foram submetidas à prova de inibiçäo indireta. Verificou-se que 20,8 por cento (10/48) das cepas demonstraram amplo espectro antimicrobiano frente a microrganismos como: Salmonella enteritidis var. typhimurium, Staphylococcus aureus, Listeria monocytogenes e Listeria innocua. Nenhuma das cepas isoladas foi capaz de inibir Escherichia coli

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