Baroreflex sensitivity differs among same strain Wistar rats from the same laboratory

Previous studies showed that a proportion of normotensive Sprague-Dawley rats spontaneously exhibit lower baroreflex sensitivity. However, investigations have not yet been carried out on Wistar rats. We aimed to compare baroreflex sensitivity among rats from the same strain and the same laboratory. Male Wistar normotensive rats (300–400g) were studied. Cannulas were inserted into the abdominal aortic artery through the right femoral artery to measure mean arterial pressure and heart rate. Baroreflex was calculated as the derivative of the variation of heart rate in function of the mean arterial pressure variation (ΔHR/ΔMAP) tested with a depressor dose of sodium nitroprusside (50 µg/kg) and with a pressor dose of phenylephrine (8µg/kg) in the right femoral venous approach through an inserted cannula. We divided the rats into four groups: i) high bradycardic baroreflex, baroreflex gain less than −2 tested with phenylephrine; ii) low bradycardic baroreflex, baroreflex gain between −1 and −2 tested with phenylephrine; iii) high tachycardic baroreflex, baroreflex gain less than −3 tested with sodium nitroprusside; and iv) low tachycardic baroreflex, baroreflex gain between −1 and −3 tested with sodium nitroprusside. Approximately 71% of the rats presented a decrease in bradycardic reflex while around half showed an increase in tachycardic reflex. No significant changes in basal mean arterial pressure and heart rate, tachycardic and bradycardic peak and heart rate range were observed. There was a significant change in baroreflex sensitivity among rats from the same strain and the same laboratory

HHV-8 infection in patients with AIDS-related Kaposi's sarcoma in Brazil

The aims of the present study were to determine the prevalence of human herpesvirus type 8 (HHV-8) in HIV-positive Brazilian patients with (HIV+/KS+) and without Kaposi's sarcoma (HIV+/KS-) using PCR and immunofluorescence assays, to assess its association with KS disease, to evaluate the performance of these tests in detecting HHV-8 infection, and to investigate the association between anti-HHV-8 antibody titers, CD4 counts and staging of KS disease. Blood samples from 66 patients, 39 HIV+/KS+ and 27 HIV+/KS-, were analyzed for HHV-8 viremia in peripheral blood mononuclear cells by PCR and HHV-8 antigenemia for latent and lytic infection by immunofluorescence assay. Positive samples for latent nuclear HHV-8 antigen (LNA) antibodies were titrated out from 1/100 to 1/409,600 dilution. Clinical information was collected from medical records and risk behavior was assessed through an interview. HHV-8 DNA sequences were detected by PCR in 74.3% of KS+ patients and in 3.7% of KS- patients. Serological assays were similar in detecting anti-LNA antibodies and anti-lytic antigens in sera from KS+ patients (79.5%) and KS- patients (18.5%). HHV-8 was associated with KS whatever the method used, i.e., PCR (odds ratio (OR) = 7.4, 95% confidence interval (CI) = 2.16-25.61) or anti-LNA and anti-lytic antibodies (OR = 17.0, 95%CI = 4.91-59.14). Among KS+ patients, HHV-8 titration levels correlated positively with CD4 counts (rho 0.48, P = 0.02), but not with KS staging. HHV-8 is involved in the development of KS in different geographic areas worldwide, as it is in Brazil, where HHV-8 is more frequent among HIV+ patients. KS severity was associated with immunodeficiency, but no correlation was found between HHV-8 antibody titers and KS staging

Relationship of methionine plus cystine with lysine in diets for laying Japanese quails Relação metionina mais cistina com lisina em dietas para codornas japonesas em postura

The objective of this work was to evaluate the relationships of methionine plus cystine with lysine for Japanese quails in the laying phase. Thus, it was used 480 birds at initial age of 65 days, distributed in randomized block design with 6 treatments, 10 replicates and 8 birds per experimental unit. The treatments consisted of basal diet deficient in methionine plus cystine (0.65%), with 19.6% of crude protein and 2800 kcal of metabolizable energy/kg of ration, supplemented with six levels of DL-methionine 98% (0.116; 0.167; 0.218; 0.269; 0.320 and 0.371%), corresponding to methionine plus cystine with lysine ratio of 0.65, 0.70, 0.75, 0.80, 0.85 and 0.90, and the digestible lysine set at a suboptimal level of 1.00. The parameters studied were: feed intake, egg production per hen day, egg production per housed hen, commercial egg production, egg weight, egg mass, feed conversion per egg mass, feed conversion per dozen eggs, viability of birds, weight of the egg components (yolk, albumen and shell), percentage of components of eggs, diameter and height of the eggs and specific gravity. It was observed an increasing linear effect for feed intake, egg diameter, shell weight and percentage of yolk. For eggshell percentage, it was observed a decreasing linear effect. For the weight of the eggs, the best adjustment was obtained by using the Linear Response Plateau model. A quadratic effect was observed for egg mass, feed conversion per egg mass, egg production per hen day, egg production per housed hen, yolk weight, albumen weight and height of the eggs. The relationship of methionine plus cystine with lysine of 0.84 which corresponds to the consumption of 221.0 mg/bird/day of methionine + cystine provides better performance and satisfactory quality of Japanese quail eggs.<br>Com o objetivo de avaliar o efeito de relações entre metionina mais cistina com lisina para codornas japonesas na fase de postura, 480 aves com idade inicial de 65 dias foram distribuídas em delineamento em blocos casualisados com 6 tratamentos, 10 repetições e 8 aves por unidade experimental. Os tratamentos consistiram de ração basal deficiente em metionina mais cistina (0,65%), com 19,6% de proteína bruta e 2800 kcal de energia metabolizável/kg de ração, suplementada com seis níveis de DL-metionina 98% (0,116; 0,167; 0,218; 0,269; 0,320 e 0,371%), correspondendo à relação metionina mais cistina com lisina de 0,65; 0,70; 0,75; 0,80; 0,85 e 0,90, sendo a lisina digestível fixada no nível sub ótimo de 1,00. Os parâmetros estudados foram: consumo de ração, produção de ovos por ave dia, produção de ovos por ave alojada, produção de ovos comercializáveis, peso do ovo, massa de ovos, conversão alimentar por massa de ovos, conversão alimentar por dúzia de ovos, viabilidade das aves, peso dos componentes dos ovos (gema, albúmen e casca), porcentagem dos componentes dos ovos, diâmetro e altura dos ovos e gravidade específica. Observou-se efeito linear crescente para consumo de ração, diâmetro dos ovos, peso da casca e porcentagem de gema. Para porcentagem de casca foi observado efeito linear decrescente. Para o peso dos ovos o melhor ajuste foi obtido com a utilização do modelo Linear Response Plateau. Foi verificado efeito quadrático para a massa de ovos, conversão alimentar por massa de ovos, produção de ovos por ave dia, produção de ovos por ave alojada, peso da gema, peso do albúmen e altura dos ovos. A relação metionina mais cistina com lisina de 0,84 que corresponde ao consumo de 221,0 mg/ave/dia de metionina + cistina proporciona melhor desempenho e satisfatória qualidade de ovo de codornas japonesas