Optimizing the transport of porcine semen: a proposal for Brazil / Otimizar o transporte do sêmen suíno: uma proposta para o Brasil

Semen from the first 15mL of the ejaculate (P1) obtained from two boars (30mL) was diluted in glycine-egg yolk extender, cooled at 5°C in a special container and rediluted in standard doses of 3x109 mobile spermatozoa after 12h of storage. Semen was also stored up to 24h after redilution. The physical characteristics of the semen were evaluated at different storage periods (fresh, 0h, 12h, rediluted, 24h, and 36h). The reproductive performance of the boars and their fertility regarding the insemination of primiparous sows were also determined. Two treatments were used: T1-15B sows inseminated with semen originated from hyperconcentrated heterospermic doses (15x109 mobile spermatozoa per dose), rediluted after 12h of storage at 5°C for standard doses of 3x109 mobile spermatozoa per dose and stored at 5°C up to 24h after redilution (n=10); T2-3B sows inseminated with standard heterospermic doses (3x109 mobile spermatozoa per dose), stored at 5°C up to 36h after semen collection (n=10). There was no effect (P>0.05) of treatments on the spermatic motility, even though a pronounced decrease (P>0.05) of their values at 12h of storage was recorded. However, they remained higher than 70% until 36h. There was effect of treatments on spermatic vigour at 0h (P<0.05), when T1-15B vigour was higher. There was also effect of the storage period for both treatments with a progressive decrease throughout 36h of storage, although the differences were not always significant. Pregnancy rates (90%) and the number of total farrowed piglets (15, 11-T1-15B; 13, 44- T2-3B) did not differ (P>0.05) between the treatments. It was concluded that the semen hyperconcentration of 15 billion of mobile spermatozoa per dose, stored at 5°C for 12h, did not result in drawbacks considering the physical characteristics of the semen, maintaining the pregnancy rates and prolificacy of the inseminated sows.

Os primeiros 15mL do ejaculado (P1) de dois varrões foram coletados (30mL) e diluídos em diluidor glicina-gema de ovo, resfriados a 5°C em contêiner especial e rediluídos para doses padrão de 3x109 espermatozoides (sptz) móveis, após 12 horas de armazenamento. Além disso, foram armazenados por até 24 horas após a rediluição, sendo as características físicas avaliadas em diferentes períodos de estocagem (fresco, zero hora, 12h, Red12h, 24h e 36h) e a fertilidade avaliada por meio de fêmeas primíparas inseminadas. Foram realizados dois tratamentos: T1-15B: porcas inseminadas com sêmen de doses heterospérmicas hiperconcentradas (15x109 sptz móveis/dose), rediluídas após 12 horas de armazenamento a 5°C para doses padrão de 3x109 sptz móveis/dose, e armazenadas a 5°C por até 24 horas após a rediluição (n=10); T2-3B: porcas inseminadas com doses heterospérmicas padrão (3x109 sptz móveis/dose), armazenadas a 5°C por até 36 horas após coleta. Não houve efeito (P>0.05) dos tratamentos sobre a motilidade espermática e, embora tenha ocorrido queda (P<0.05) às 12 horas, a motilidade foi superior a 70% durante as 36 horas de armazenamento. Houve efeito (P<0.05) dos tratamentos no tempo zero hora quanto ao vigor espermático, sendo E1T1-15B superior. Além disso, houve efeito do período de estocagem para os dois tratamentos, com queda progressiva do vigor ao longo das 36 horas, embora nem sempre as diferenças tenham sido significativas. As taxas de gestação (90%) e o número total de leitões nascidos (15, 11 - T1-15B; 13, 44 - T2-3B) não diferiram (P>0.05) entre os tratamentos. Concluiu-se que a hiperconcentração do sêmen para 15x109 sptz móveis/dose, armazenado a 5°C por 12 horas não resultou em prejuízos quanto à manutenção das características físicas do sêmen e ao desempenho reprodutivo dos varrões, sendo capaz de manter a taxa de gestação e a prolificidade das fêmeas inseminadas.

Possible involvement of a phosphatidylinositol-type signaling pathway in glucose-induced activation of plasma membrane H(+)-ATPase and cellular proton extrusion in the yeast Saccharomyces cerevisiae.

Addition of glucose to cells of the yeast Saccharomyces cerevisiae causes rapid activation of plasma membrane H(+)-ATPase and a stimulation of cellular H+ extrusion. We show that addition of diacylglycerol and other activators of protein kinase C to intact cells also activates the H(+)-ATPase and causes at the same time a stimulation of H+ extrusion from the cells. Both effects are reversed by addition of staurosporine, a protein kinase C inhibitor. Addition of staurosporine or calmidazolium, an inhibitor of Ca2+/calmodulin-dependent protein kinases, separately, causes a partial inhibition of glucose-induced H(+)-ATPase activation and stimulation of cellular H+ extrusion; together they cause a more potent inhibition. Addition of neomycin, which complexes with phosphatidylinositol 4,5-bisphosphate, or addition of compound 48/80, a phospholipase C inhibitor, also causes near complete inhibition. Diacylglycerol and other protein kinase C activators had no effect on the activity of the K(+)-uptake system and the activity of trehalase and glucose-induced activation of the K(+)-uptake system and trehalase was not inhibited by neomycin, supporting the specificity of the effects observed on the H(+)-ATPase. The results support a model in which glucose-induced activation of H(+)-ATPase is mediated by a phosphatidylinositol-type signaling pathway triggering phosphorylation of the enzyme both by protein kinase C and one or more Ca2+/calmodulin-dependent protein kinases.

[Canine visceral leishmaniasis: evaluation of the serologic method used in epidemiologic studies]. / Leishmaniose visceral canina: avaliação da metodologia sorológica utilizada em inquéritos epidemiológicos.

A comparative study was made of eluates of the blood of dogs experimentally infected with different trypanosomatids. Using antigens prepared from promastigotes of Leishmania mexicana, L. braziliensis and L. chagasi, assessments were made by the indirect immunofluorescence test. The results showed a sensitivity of 87.5% in the diagnosis of canine visceral leishmaniasis, independent of antigen used. Cross-reactions occurred in 75% of cases of cutaneous leishmaniasis and 83.3% of dogs with chagas' disease. An epidemiological survey in an area of leishmaniasis confirmed that immunofluorescence tests on eluates of dogs' blood give cross-reactions between L. braziliensis and L. chagasi. The results suggest that such testing could be useful in public health campaigns but attention is drawn to the fact that the level of positive reactions cannot be used as an indicator of the prevalence of canine kala-azar.

The change of behavior of two strains of Leishmania after cultivation in a defined medium

Duas cepas de Leishmania originalmente isoladas in vitro de casos humanos de leishmaniose cutânea e que ab initio näo infectaram animais de laboratório, tornaram-se infectantes para hamnsters após serem mantidos por vários anos em meio de cultura quimicamente definido. Foram realizadas observaçöes sobre o crescimento de promastigotas in vitro, curso da infecçäo em hamsters, morfologia das amastigotas, mobilidade eletroforética de oito enzimas solúveis. Foram obtidas informaçöes sobre a densidade de flutuaçäo do n-DNA e do k-DNA e uma das cepas foi testada contra anticorpos monoclonais. Ambas as cepas permanecem sem identificaçäo precisa

The change of behaviour of two strains of Leishmania after cultivation in a defined medium.

Attempts have been made to characterize two strains of Leishmania that became infective to golden hamsters only after they had been maintained for several years in a chemically defined culture medium. Observations were made on the growth rates of promastigotes in vitro, course of infection in hamsters, morphology of amastigotes, and electrophoretic mobility patterns of eight isoenzymes. Information was obtained about the buoyant densities of n-DNA and k-DNA, and one strain was tested against monoclonal antibodies. The identity of both strains remains obscure.