Perfil energético e hormonal de ovelhas Santa Inês do terço médio da gestação ao pós-parto / Energetic and hormonal profile of Santa Ines ewes in the middle of gestation to postpartum

Important physiological adaptations occur in the periparturient period; their failure predispose the ewe to metabolic diseases. Knowledge of normal changes makes an early recognition and treatment of mal functions possible and enables prevention of diseases and losses. The biochemical profile of Santa Ines ewes from the 88th day of gestation until 28 days after parturition was evaluated and compared to non pregnant controls. The ewes were divided in groups according to the number of fetuses: G0, non pregnant (10); G1, one (10); G2, two and three fetuses (14). All animals had their heart and respiratory rates as well as their ruminal motility recorded. Serum and plasma was analyzed for the following parameters: glucose, non esterified fatty acids (NEFA), beta hydroxibutyrate (BHB), T3, T4, insulin, glucagon and cortisol activities. Results showed changes in biochemical variables of energy and protein profile during pregnancy and parturition. During the last third of gestation, all ewes showed slightly increased NEFA, T3 and T4 levels when compared to non pregnant ewes. At lambing pregnant ewes, had higher glucose, NEFA and T3 levels. No significant differences on measured parameters comparing simple and multiple gestations were observed. Therefore, when there is adequate adaptation in this period of high metabolic challenge, biochemical parameters considered here are independent of the number of fetuses gestate and can be considered as reference values for a pregnant ewes from the middle third of gestation to first month postnatal period.

No período periparto ocorrem importantes adequações fisiológicas que, se não forem efetivas predispõem a fêmea a enfermidades metabólicas. O conhecimento desta adaptação é relevante para que sejam implementadas, precocemente, medidas preventivas a poupar perdas produtivas. Com este objetivo foi avaliado o perfil energético e hormonal de ovelhas Santa Inês durante a gestação e puerpério. Foram utilizadas 10 ovelhas não gestantes (G0), 10 gestantes de um (G1) e 14 gestantes de dois e três fetos (G2). Foram avaliadas concentrações plasmáticas de glicose, ácidos graxos não esterificados (AGNE), betahidroxibutirato (BHB), e as concentrações séricas de insulina, glucagon, cortisol, triiodotironina (T3) e tiroxina (T4) a partir do 88º dia de gestação até o 28º dia pós-parto. No terço final de gestação, ovelhas gestantes apresentaram maiores concentrações de AGNE, T3 e T4 que as ovelhas não gestantes. No momento do parto foram observadas maiores concentrações de glicose, AGNE e T3 para todas as ovelhas gestantes em relação às não gestantes. Não houve diferença entre as ovelhas gestantes de um, dois ou três fetos. As diferenças observadas ocorreram apenas entre ovelhas gestantes e as vazias. Portanto, quando há adequada adaptação neste período de elevado desafio metabólico, os parâmetros bioquímicos aqui considerados independem do número de fetos gestados e podem ser considerados como valores de referência para ovelhas gestantes de um feto ou mais fetos do terço médio de gestação ao primeiro mês pós-parto.

Prevalence of transmitted HIV-1 antiretroviral resistance among patients initiating antiretroviral therapy in Brazil: a surveillance study using dried blood spots.

INTRODUCTION: In Brazil, the use of antiretrovirals is widespread: more than 260,000 individuals are currently undergoing treatment. We conducted a survey targeting antiretroviral-naïve individuals who were initiating antiretroviral therapy (ART) according to local guidelines. This survey covered five Brazilian regions. METHODS: The HIV Threshold Survey methodology (HIV-THS) of the World Health Organization was utilized, and subjects were selected from seven highly populated cities representative of all Brazilian macro-regions. Dried blood spots (DBS) were collected on SS903 collection cards and were transported by regular mail at room temperature to a single central laboratory for genotyping. RESULTS: We analysed samples from 329 individuals initiating highly active antiretroviral therapy (HAART), 39 (11.8%) of whom were harbouring transmitted drug resistance (TDR). The mean CD4+ T cell count was 253 cells/µL, and the mean viral load was 142,044 copies/mL. The regional prevalence of resistance was 17.0% in the Northeast, 12.8% in the Southeast, 10.6% in the Central region, 8.5% in the North and 8.5% in the South. The inhibitor-specific TDR prevalence was 6.9% for nucleoside reverse transcriptase inhibitors, 4.9% for non-nucleoside reverse transcriptase inhibitors and 3.9% for protease inhibitors; 3.6% of individuals presented resistance to more than one class of inhibitors. Overall, there were trends towards higher prevalences of subtype C towards the South and subtype F towards the North. Of the DBS samples collected, 9.3% failed to provide reliable results. DISCUSSION: We identified variable TDR prevalence, ranging from intermediate to high levels, among individuals in whom HIV disease progressed, thus implying that resistance testing before initiating ART could be effective in Brazil. Our results also indicate that the use of DBS might be especially valuable for providing access to testing in resource-limited and remote settings.

Short communication: HIV type 1 subtype BF leads to faster CD4+ T cell loss compared to subtype B.

Although it has been suggested that biological differences among HIV-1 subtypes exist, their possible influence on disease progression has not been fully revealed. In particular, the increasing emergence of recombinants stresses the need to characterize disease presentation in persons infected by these diverse HIV-1 forms. We explored this issue among 83 Brazilian subjects infected with either HIV-1 subtype B or recombinant subtype BF, all followed since incident infection in a cohort study. Viral subtypes were assigned by full length sequencing of HIV-1 genomes. We observed that the baseline measures for CD4(+) T cells and viral load did not differ between the groups. However, longitudinal analysis revealed that subtype BF was clearly associated with a faster CD4(+) T cell decline compared to infection with subtype B, in spite of a similar plasma HIV-1 load. While subtype B-infected subjects presented a loss of 3.6 CD4(+) T cells/µl per month, subtype BF-infected individuals showed a monthly decay of 6.3 CD4(+) T cells/µl (p<0.01). The time to reach 350 CD4(+) T cells/µl and the time to start antiretroviral treatment were also shorter in subtype BF-infected persons. The elucidation of an accelerated CD4(+) T cell loss associated with subtype BF suggests that this HIV-1 genetic form could be more pathogenic than subtype B.

Oxidative metabolism and muscle biochemical profile of polo horses supplemented with an ADE vitamin complex / Metabolismo oxidativo e perfil bioquímico muscular de cavalos de pólo suplementados com complexo vitamínico ADE

Horses used for the game of polo experience abrupt and frequent changes in exercise intensity. To meet this variable energy demand, the horses use both aerobic and anaerobic pathways in varying proportions and intensities. In this context, there must be a balance between the formation of reactive oxygen species (ROS) and the action of antioxidants to prevent oxidative stress and its consequences. The effect of supplementation with an ADE vitamin complex on oxidative metabolism was evaluated in 18 crossbred horses randomly divided between a treated group (TG) and a control group (CG). The TG animals received the ADE vitamin complex (1mL/50 kg of body weight) by deep intramuscular injection at 30 and 15 days before the game. The CG horses received 10ml of saline by the same administration route and schedule. During the polo match, the animals played for a total of 7.5 min. Blood samples were collected on the same days as the treatments were administered, and immediately before and at 15, 90 and 180 minutes after the game. The concentrations of creatine phosphokinase (CK), lactate dehydrogenase (LDH), lactate, glucose, aspartate aminotransferase (AST), glutathione (GSH), superoxide dismutase (SOD) and malondialdehyde (MDA) were measured in the blood samples. After the game, the TG demonstrated higher levels of AST, lactate and glucose than the CG, suggesting more efficient energy use by the treated animals. The higher GSH and lower lactate levels in the TG before the game suggest the presence of a greater antioxidant supply in the treated animals. The maintenance of the MDA levels indicates that neither of the groups exhibited oxidative stress.

O jogo de pólo se caracteriza por mudanças abruptas e frequentes na intensidade do exercício dos cavalos. Para satisfazer esta demanda inconstante de energia, os animais utilizam as vias aeróbia e anaeróbia em proporções e intensidade variáveis. Neste contexto deve haver equilíbrio entre a formação das espécies reativas de oxigênio (EROs) e a ação das substâncias antioxidantes a fim de evitar o estresse oxidativo e suas consequências. Avaliou-se o efeito da suplementação com vitaminas ADE no metabolismo oxidativo destes animais. Para tanto, 18 equinos mestiços foram distribuídos aleatoriamente em dois grupos: tratado e controle (GT) e controle (GC).Os animais do GT receberam complexo vitamínico ADE (1 mL/50 kg de peso vivo) pela via intramuscular profunda aos 30 e 15 dias antes do jogo. Os cavalos do GC receberam, pela mesma via de administração e nos mesmos momentos, 10mL de solução fisiológica. Os animais jogaram um tempo de 7,5min. Foram coletadas amostras de sangue nos mesmos dias de tratamento e imediatamente antes e aos 15, 90 e 180 minutos após o jogo. Foram determinadas as concentrações sanguíneas de CK, LDH, lactato, glicose, AST, GSH, SOD e MDA. Após o jogo o GT apresentou maiores valores para AST, lactato e glicemia que o GC, sugerindo melhor aproveitamento energético dos animais tratados. Os valores maiores de GSH e menores de lactato no GT antes da prova sugerem maior aporte antioxidante nos animais tratados. A manutenção dos teores de MDA indica que nenhum dos grupos entrou em estresse oxidativo.

Differential persistence of transmitted HIV-1 drug resistance mutation classes.

BACKGROUND: Transmitted human immunodeficiency virus type 1 (HIV-1) drug resistance (TDR) mutations can become replaced over time by emerging wild-type viral variants with improved fitness. The impact of class-specific mutations on this rate of mutation replacement is uncertain. METHODS: We studied participants with acute and/or early HIV infection and TDR in 2 cohorts (San Francisco, California, and São Paulo, Brazil). We followed baseline mutations longitudinally and compared replacement rates between mutation classes with use of a parametric proportional hazards model. RESULTS: Among 75 individuals with 195 TDR mutations, M184V/I became undetectable markedly faster than did nonnucleoside reverse-transcriptase inhibitor (NNRTI) mutations (hazard ratio, 77.5; 95% confidence interval [CI], 14.7-408.2; P<.0001), while protease inhibitor and NNRTI replacement rates were similar. Higher plasma HIV-1 RNA level predicted faster mutation replacement, but this was not statistically significant (hazard ratio, 1.71 log(10) copies/mL; 95% CI, .90-3.25 log(10) copies/mL; P=.11). We found substantial person-to-person variability in mutation replacement rates not accounted for by viral load or mutation class (P<.0001). CONCLUSIONS: The rapid replacement of M184V/I mutations is consistent with known fitness costs. The long-term persistence of NNRTI and protease inhibitor mutations suggests a risk for person-to-person propagation. Host and/or viral factors not accounted for by viral load or mutation class are likely influencing mutation replacement and warrant further study.

Molecular and structural characterization of HIV-1 subtype B Brazilian isolates with GWGR tetramer at the tip of the V3-loop.

One of most intriguing features of the HIV-1 subtype B epidemic in Brazil is the high frequency of isolates exhibiting tryptophan (W) in the tetramer (GWGR) at the tip of the V3 loop. We observed that the frequencies of glutamic and aspartic acids at site 25 of the V3 loop are quite distinct in GWGR isolates compared with viruses with other tetramers. The basic amino acids at sites 11 and 25 of V3 are strongly linked with CCR5-to-CXCR4 coreceptor shift. We therefore predicted phenotype usage and found that GWGR isolates are exclusively CCR5-using. Further evidence of this came from intrahost sequences, where basic amino acid substitutions at sites 11 and 25 emerged only in isolates presenting a tryptophan-to-glycine replacement at the tetramer of the V3. In addition, modeled 3D-structures of the V3 loop of GWGR and GGGR in intrahost viruses differ essentially in the binding region of the coreceptor.

Quality assurance program for peripheral blood mononuclear cell cryopreservation.

Seven Brazilian sites participating in the Pediatric AIDS Clinical Trials Group international cryopreservation quality assurance pilot program cryopreserved and shipped peripheral blood mononuclear cells (PBMC) to a central U.S. laboratory for analysis. Cell viability and recovery significantly increased over time. A wet-laboratory training session conducted at the central laboratory significantly improved the quality of the cryopreserved PBMC.