Reproductive biology of Tambaqui, Colossoma macropomum Cuvier, 1818 (Teleostei, Serrasalmidae), in the lower Amazon, Brazil

This study analysed the reproductive biology of the tambaqui Colossoma macropomum in the Lower Amazon. 1232 individuals were collected from October 1994 to February 1996 from landings in Santarém in Pará State. Individuals between 20 and 120cm total length were weighted, measured, sexed and classified according to their maturity stage. Fecundity and spawning type were determined to analysing intra-ovarian oocytes of 10 adult females. Colossoma macropomum is a total spawner. There are changes at different levels: macro and microscopic cycles according to hydrological periods. Mature individuals occurred between november and february, indicating that spawning take place during this period, at the beginning of flood. The sexual rate changes with the size of fishes. Males are more frequent between 40 and 75cm, and the females between 80 and 115cm. The length/weight relationship indicates differences in the growth between males and females. The average fecundity was estimated on 1.007.349 eggs per female. There is a significant relationship between fecundity and total weight. The equation founded to tambaqui in the Lower Amazon was F = 885347 + 9,16 W1.Analisaram-se aspectos da biologia reprodutiva do tambaqui (Colossoma macropomum) na região do Baixo Amazonas. Foram coletados 1232 exemplares entre outubro de 1994 e fevereiro de 1996, nos mercados e frigoríficos de Santarém no Estado do Pará. Indivíduos entre 20 e 120 cm foram pesados, medidos e observados o sexo e o estágio de maturidade. O tipo de desova e a fecundidade foram determinados através da análise dos ovócitos intraovarianos de 10 fêmeas maduras. Colossoma macropomum possui desova total. Existem variações macro e microscópicas cíclicas dos ovários associadas ao período hidrológico. A desova coincidiu com o início do período das chuvas. A proporção sexual varia com o tamanho dos peixes. A relação comprimento/peso indica diferenças nas estratégias de crescimento para ambos os sexos. O menor macho sexualmente maduro mediu 62 cm e o maior 95 cm, no caso das fêmeas, 70 cm e 112 cm respectivamente. A fecundidade média absoluta calculada para o tambaqui foi de 1.007.349 ovócitos (s = 67.279). Existe uma relação linear entre a fecundidade (F) e o peso total (W1) sendo a equação F = 885347 + 9,16 W1

Dinâmica sazonal e interanual da estrutura populacional e do impacto da exploração pesqueira do jaraqui de escama fina (Semaprochilodus taeniurus) e jaraqui escama grossa (S. insignis) (Schomburgki, 1841) em subsistemas hidrográficos da Amazônia Central

Os jaraquis são caraciformes da Amazônia de grande importância comercial na região, constituindo um dos principais grupos de peixes que fornece a maior parte do pescado disponível para consumo. A pesca destas espécies ocorre nos principais rios durante os períodos de migração reprodutiva e de dispersão. A dinâmica sazonal e interanual da estrutura populacional e do impacto da exploração pesqueira dos jaraquis (Semaprochilodus taeniurus e S. insignis) nos subsistemas hidrográficos da Amazônia Central foi avaliada a partir de dados da pesca comercial desembarcada em Manaus nas safras de jaraquis durante a migração de dispersão (entre os meses de abril e junho de 1996-2000 e no período de migração reprodutiva (entre janeiro e março de 1996-2000). Foram analisados aspectos da biologia pesqueira e dinâmica populacional das espécies tais como: composição de tamanhos médios de L50 de jaraquis avaliada através de ANOVA com medidas repetidas no tempo; proporção de sexos comparada por subsistema e por ano aplicado a estatística "G; fator de condição ; as relaçSes peso-comprimento, confrotando-se declividades das regressSes pelo teste de paralelismo. A idade dos jaraquis foi determinada pelo método do Incremento Marginal Relativo (IMR) e do retrocalculo à idades passadas. Os parâmetros de crescimento foram estimados através do Método de Máxima Semelhança Verdadeira (MSV) e o rendimento máximo sustentável, através do método de Beverton & Holt (1957). A maior parcela da população capturada pela pesca comercial em todos os subsistemas é de juvenis de ambas as espécies como consequência de primeira maturação em todos os subsistemas das duas espécies está dimunindo ao longo do tempo. Foram detectadas diferentes entre os parâmetros populacionais das duas espécies de jaraquis nos subsistemas estudados. O ótimo da mortalidade por pesca para atingir o rendimento máximo sustentável foi menor que a atual para ambas as espécies, indicando sobrepesca de crescimento em todos os subsistemas. As evidências apontam para a necessidade de proteção da parcela jovem da população dos jaraquis vulneráveis à pesca durante o período de dispersão quando migram ativamente pelos rios da Amazônia

Caracterização das notificações de violência em crianças no município de Ribeirão Preto, São Paulo, no período 2006-2008

Resumo OBJETIVO: descrever os casos de violência contra crianças notificados no município de Ribeirão Preto-SP, Brasil. MÉTODOS: estudo descritivo com dados do Sistema de Vigilância de Violências e Acidentes (VIVA) da Secretaria Municipal de Saúde de Ribeirão Preto-SP, Brasil, no período de 2006 a 2008. RESULTADOS: foram registrados 498 casos de violência contra crianças (0-9 anos) no período, com elevação no número de notificações, de 112 em 2006 a 197 em 2008, 79,3% das notificações foram provenientes da área da Saúde, a maioria das crianças era do sexo feminino (56,4%) e apresentava idade entre dois e cinco anos (mais de 60%); prevaleceram agressores do sexo masculino (53,6%), com destaque para a figura paterna (22,7%); agressões físicas foram as mais frequentes (59,2%) e o local de maior ocorrência foi a casa da família (75,5%). CONCLUSÃO: predominaram vítimas do sexo feminino, agredidas por homens, predominantemente pais e outros familiares, na casa da família

Electrophysiological characterization of Tityus obscurus beta toxin 1 (To1) on Na+-channel isoforms

To1, previously named Tc49b, is a peptide neurotoxin isolated from venom of the scorpion Tityus obscurus that is responsible for lethal human poisoning cases in the Brazilian Amazonian region. Previously, To1 was shown to be lethal to mice and to change Na+ permeation in cerebellum granular neurons from rat brain. In addition, To1 did not affect Shaker B K+ channels. Based on sequence similarities, To1 was described as a β-toxin. In the present work, To1 was purified from T. obscurus venom and submitted to an electrophysiological characterization in human and invertebrate NaV channels. The analysis of the electrophysiological experiments reveal that To1 enhances the open probability at more negative potentials of human NaV 1.3 and 1.6, of the insect channel BgNaV1 and of arachnid VdNaV1 channel. In addition, To1 reduces the peak of Na+ currents in some of the NaVs tested. These results support the classification of the To1 as a β-toxin. A structure and functional comparison to other β-toxins that share sequence similarity to To1 is also presented.status: publishe

Evaluation of the immunosuppressive effect of cyclophosphamide and dexamethasone in mice with visceral toxocariasis

Visceral toxocariasis is a serious public health problem with a cosmopolitan distribution. Children are susceptible due to their immature immune system and high risks of infection. Nevertheless, the few completed studies about immunosuppression have had controversial results. To evaluate the effect of two immunosuppressive drugs on the larval burden of Toxocara canis, four groups of ten Swiss strain mice each were inoculated on day 0 with 1,200 embryonated T. canis eggs. Fifteen days before the experimental infection, group 1 (control) was treated via intraperitoneal injection (IP) with sterile distilled water and groups 2 and 3 were treated with dexamethasone (DEX) at 1 and 5 mg/kg/day, respectively. Additionally, group 4 was treated IP with cyclophosphamide (CY) at 50 mg/kg at two times per week for 2 weeks. Sixty days following infection, the mice were euthanised to recover the larvae by means of the tissue digestion technique. The levels of antibodies detected by indirect ELISA were not associated with the larval burden. Administration of CY (50 mg/kg) and DEX (5 mg/kg) resulted in an increase of the larval burden of 162.1% and 50.8%, respectively, in relation to the control group. These two treatments, especially CY (50 mg/kg), promoted immunosuppression and the establishment of a significant larval burden, supporting its further utilisation in studies related to immunosuppression in visceral toxocariasis

Health-status outcomes with invasive or conservative care in coronary disease

BACKGROUND In the ISCHEMIA trial, an invasive strategy with angiographic assessment and revascularization did not reduce clinical events among patients with stable ischemic heart disease and moderate or severe ischemia. A secondary objective of the trial was to assess angina-related health status among these patients. METHODS We assessed angina-related symptoms, function, and quality of life with the Seattle Angina Questionnaire (SAQ) at randomization, at months 1.5, 3, and 6, and every 6 months thereafter in participants who had been randomly assigned to an invasive treatment strategy (2295 participants) or a conservative strategy (2322). Mixed-effects cumulative probability models within a Bayesian framework were used to estimate differences between the treatment groups. The primary outcome of this health-status analysis was the SAQ summary score (scores range from 0 to 100, with higher scores indicating better health status). All analyses were performed in the overall population and according to baseline angina frequency. RESULTS At baseline, 35% of patients reported having no angina in the previous month. SAQ summary scores increased in both treatment groups, with increases at 3, 12, and 36 months that were 4.1 points (95% credible interval, 3.2 to 5.0), 4.2 points (95% credible interval, 3.3 to 5.1), and 2.9 points (95% credible interval, 2.2 to 3.7) higher with the invasive strategy than with the conservative strategy. Differences were larger among participants who had more frequent angina at baseline (8.5 vs. 0.1 points at 3 months and 5.3 vs. 1.2 points at 36 months among participants with daily or weekly angina as compared with no angina). CONCLUSIONS In the overall trial population with moderate or severe ischemia, which included 35% of participants without angina at baseline, patients randomly assigned to the invasive strategy had greater improvement in angina-related health status than those assigned to the conservative strategy. The modest mean differences favoring the invasive strategy in the overall group reflected minimal differences among asymptomatic patients and larger differences among patients who had had angina at baseline

Initial invasive or conservative strategy for stable coronary disease

BACKGROUND Among patients with stable coronary disease and moderate or severe ischemia, whether clinical outcomes are better in those who receive an invasive intervention plus medical therapy than in those who receive medical therapy alone is uncertain. METHODS We randomly assigned 5179 patients with moderate or severe ischemia to an initial invasive strategy (angiography and revascularization when feasible) and medical therapy or to an initial conservative strategy of medical therapy alone and angiography if medical therapy failed. The primary outcome was a composite of death from cardiovascular causes, myocardial infarction, or hospitalization for unstable angina, heart failure, or resuscitated cardiac arrest. A key secondary outcome was death from cardiovascular causes or myocardial infarction. RESULTS Over a median of 3.2 years, 318 primary outcome events occurred in the invasive-strategy group and 352 occurred in the conservative-strategy group. At 6 months, the cumulative event rate was 5.3% in the invasive-strategy group and 3.4% in the conservative-strategy group (difference, 1.9 percentage points; 95% confidence interval [CI], 0.8 to 3.0); at 5 years, the cumulative event rate was 16.4% and 18.2%, respectively (difference, 121.8 percentage points; 95% CI, 124.7 to 1.0). Results were similar with respect to the key secondary outcome. The incidence of the primary outcome was sensitive to the definition of myocardial infarction; a secondary analysis yielded more procedural myocardial infarctions of uncertain clinical importance. There were 145 deaths in the invasive-strategy group and 144 deaths in the conservative-strategy group (hazard ratio, 1.05; 95% CI, 0.83 to 1.32). CONCLUSIONS Among patients with stable coronary disease and moderate or severe ischemia, we did not find evidence that an initial invasive strategy, as compared with an initial conservative strategy, reduced the risk of ischemic cardiovascular events or death from any cause over a median of 3.2 years. The trial findings were sensitive to the definition of myocardial infarction that was used