Allele- and parent-of-origin-specific effects on expression of the KCNJ11 gene: A candidate for meat tenderness in cattle.

In contrast to the Mendelian inheritance model, parental alleles can contribute unequally to gene expression, which may result in phenotypic variance among individuals and bias in the predicted additive effect of molecular markers associated with production traits. Given the need to understand the effects of allelic variation and parent-of-origin effects on the expression of genes with a commercial interest in cattle, we analyzed the expression of KCNJ11 (potassium inwardly rectifying channel, subfamily J, member 11), which was previously described as a functional candidate gene for meat tenderness. Allele-specific and parent-of-origin-dependent expression of this gene were assessed in bovine muscle using the rs379610823 single nucleotide polymorphism as a reference. Biallelic expression was observed; however, the T allele was expressed at significantly higher levels than the C allele. Furthermore, increased expression of KCNJ11 was found in animals harboring the maternal T allele. This study is the first to describe the differential allelic expression of bovine KCNJ11. Our findings are important for understanding the mechanisms that underlie the pattern of KCNJ11 expression and its potential impact on the phenotypic variation of meat tenderness in Nelore beef cattle. This reinforces the need for further investigation of allelic- and parent-of-origin expression deviation in genetic markers eligible for the selection of target traits.

Comparison of penalties resulting from first-order and all-order polarization mode dispersion distortions in optical fiber transmission systems.

We compare the eye-opening penalty from a first-order polarization mode dispersion (PMD) model with that from an all-order PMD model in optical fiber transmission systems. Evaluating the performance by taking into account only first-order PMD produces a good approximation of the true eye-opening penalty of uncompensated systems when the penalty is low. However, when the penalties are high, this model overestimates the penalty for outage probabilities in the range of interest for systems designers, which is typically approximately 10(-5) to 10(-6).

Controlled field trials of a vaccine against New World cutaneous leishmaniasis.

Two controlled, double blind field trials of a non-living promastigote vaccine against New World Cutaneous Leishmaniasis (NWCL) were conducted in 1981 and 1983 in Brazil. Brazilian Army conscripts were randomly assigned to the vaccine or placebo groups and tested during their training in the Amazon jungle, a high risk area for NWCL. The results obtained showed: no significant differences between the vaccine and the placebo groups with respect to a number of characteristics (age, race, previous contact with the jungle, etc.); no significant differences between the participants who got and who did not get NWCL during the trial, with respect to length of exposure, contact with the jungle, etc. and a reduction of 67.3 and 85.7% in the annual incidence rate of NWCL, in 1981 and 1983 respectively (although the difference between incidence rates of the disease in vaccinated and control groups in the 1983 trial was not statistically significant), among those vaccinated who had converted to a positive leishmanin skin test as compared with the placebo groups.

Some characteristics of the hyperreactivity to bacterial lipopolysaccharide induced in mice by Trypanosoma cruzi infection.

Mice infected with T. cruzi, Y strain, acquire a high level of susceptibility to the effects of bacterial gram-negative LPS. The LD50 of adult female SW mice to LPS from S. typhosa, decreases from 450 to 2,5 mcg 10-12 days after T. cruzi infection. This hyperreactivity to LPS induced by T. cruzi presents all the characteristics of that found in infection caused by many other agents. During the acute phase of experimental infection with T. cruzi Y strain, mice generally die with a hypovolemic shock very similar to that induced in uninfected animals injected with an adequate dose of bacterial endotoxin. There is evidence for and against the hypothesis that LPS absorbed from the intestinal tract may be involved in the mechanism of death of mice during the acute phase of T. cruzi infection.

Some characteristics of hyperreactivity to bacterial lipopolysaccharide induced in mice by Trypanosoma cruzi infection.

Camundongos infectados com a cepa Y do T.cruzi adquirem elevado grau de reatividade ao LPS de S. typhosa. A LD50 de camundongos SW, adultos, femeas, com peso em torno de 20g, decresce de 450 para 2,5 mcg ao fim de 10-12 dias de infeccao.Esta hiperatividade ao LPS induzida pelo T. cruzi apresenta todas as caracteristicas daquela encontrada nas infeccoes causadas por muitos outros agentes. Durante a fase aguda da infeccao experimental com T. cruzi, cepa Y, os camundongos geralmente morrem com choque hipovolemico muito semelhante ao ocasionado por dose adequada de endotoxina bacteriana. Ha evidencias a favor e contra a hipotese de que os LPS liberados do trato intestinal estejam envolvidos no mecanismos de morte do camundongo durante a fase aguda da infeccao pela cepa Y do T.cruzi

[Protection of mice by trehalose dimycolate against lethal infection by Trypanosoma cruzi]. / Protection de souris par le dimycolate de tréhalose (tdm) contre une infection létale par Trypanosoma cruzi.

Four weekly injections of 50 micrograms of trehalose dimycolate (TDM) in FIA protect 40% of the Mice against a lethal infection by Trypanosoma cruzi; under the same conditions MDP (muramyldipeptide) has only a very slight effect.

Acquired resistance of mice against S. mansoni and lung granulomatous reaction induced by BCG.

Pesquisas realizadas em camundongos Sw, nao singeneicos, mostraram nao ter havido correlacao entre a intensidade da reacao granulomatosa pulmonar e o grau de resistencia adquirida contra a infeccao por S.mansoni induzida pelo BCG

Characterization of human heterophil hemolysins induced by Schistosoma mansoni infection.

Anticorpos heterofilos foram detectados nos soros de pacientes normais ou com esquistossomose mansoni cronica. Suas atividades hemoliticas dependem da integridade da via classica do sistema do complemento.Os anticorpos heterofilos dos pacientes esquistossomoticos apresentaram maior especificidade para antigenos de Schistosoma mansoni do que aqueles anticorpos detectados nos soros de pacientes normais. A atividade hemolitica do anticorpo nos soros normais podia ser destruida pelo aquecimento destes soros a 56oC durante 4 minutos. Por outro lado, cerca de 80% dos soros de pacientes esquistossomoticos eram parcial ou totalmente resistentes ao mesmo tratamento. As atividades dos anticorpos heterofilos foram eluidas atraves da filtracao em gel, em diferentes fracoes no primeiro pico

Immunogenetic and protective activity of an extract of Schistosoma mansoni.

Avaliou-se em coelhos e camundongos, a atividade imunogenica e protetora de um extrato antigenico de Schistosoma mansoni, obtido pela estocagem de vermes adultos em solucao salina tamponada (Extrato Salino).A imunizacao dos animais determinuou o desenvolvimento de resposta imune celular e humoral, avaliada por provas especificas.Todos os coelhos imunizados com ES, desenvolveram altos niveis de anticorpo citotoxico (91 a 100%), determinados pela avaliacao de atividade citotoxica in vitro, contra esquistosomulos. Concluiu-se que os coelhos e camundongos imunizados com o extrato salino apresentaram diminuicao da carga parasitaria oriunda da infeccao posterior com cercarias de S. mansoni, em relacao aos controles. Os percentuais de protecao foram de 88.6% e 54% para os animais vacinados (coelhos e camundongos respectivamente)

Imunologia da paracoccidiodomicose. / Immunology of paracoccidioidomycosis

Estudos imunologicos foram realizados em 16 pacientes adultos, de ambos os sexos, acometidos de paracoccidioidomicose. Dentre os achados mais importantes figuram os teores elevados de IgG, a baixa do 3o. componente do complemento, a presenca de anticorpos precipitantes e hemaglutinantes contra a paracoccidioidina, a presenca de complexos imunes circulantes, baixos teores de linfocitos T circulantes, teores normais de linfocitos T supressores e hiporreatividade dos linfocitos T a fitohemaglutinina e a paracoccidioidina.A histologia das reacoes cutaneas a paracoccidioidina acusou um aspecto semelhante ao da reacao de Arthus, com o maximo de intensidade do eritema em 24 horas, a presenca de vasculite e a infiltracao predominante por polimorfonucleares

Immunization of mice with Trypanosoma cruzi polyribosomes.

Studies were carried out with a polyribosomal fraction isolated from Trypanosoma cruzi Y epimastigotes, with the intention to determine both its immunogenic activity and the degree of protection it could induce against experimental T. cruzi infection. This fraction was assayed in four groups of mice by using different schedules of vaccination and varying the dose, intervals, and route of administration. Seven days after the last dose, the animals were sacrificed for immunological studies or subjected to challenge with T. cruzi trypomastigotes. The results obtained in all schedules showed that our polyribosomal fraction only induced a weak antibody response, but was capable of evoking an expressive cellular response. It was also shown that this fraction has the capacity of inducing a high degree of protection against T. cruzi infection, as determined by the decrease of parasitemia and the prolonged survival time of immunized animals.