Digestion of yeasts and Beta-1, 3-Glucanases in mosquito larvae:physiological and biochemical considerations

Aedes aegypti larvae ingest several kinds of microorganisms. In spite of studies regarding mosquito digestion, little is known about the nutritional utilization of ingested cells by larvae. We investigated the effects of using yeasts as the sole nutrient source for A. aegypti larvae. We also assessed the role of beta-1,3-glucanases in digestion of live yeast cells. Beta-1,3-glucanases are enzymes which hydrolyze the cell wall beta-1,3-glucan polyssacharide. Larvae were fed with cat food (controls), live or autoclaved Saccharomyces cerevisiae cells and larval weight, time for pupation and adult emergence, larval and pupal mortality were measured. The presence of S. cerevisiae cells inside the larval gut was demonstrated by light microscopy. Beta-1,3-glucanase was measured in dissected larval samples. Viability assays were performed with live yeast cells and larval gut homogenates, with or without addition of competing beta-1,3-glucan. A. aegypti larvae fed with yeast cells were heavier at the 4th instar and showed complete development with normal mortality rates. Yeast cells were efficiently ingested by larvae and quickly killed (10% death in 2h, 100% in 48h). Larvae showed beta-1,3-glucanase in head, gut and rest of body. Gut beta-1,3-glucanase was not derived from ingested yeast cells. Gut and rest of body activity was not affected by the yeast diet, but head homogenates showed a lower activity in animals fed with autoclaved S. cerevisiae cells. The enzymatic lysis of live S. cerevisiae cells was demonstrated using gut homogenates, and this activity was abolished when excess beta-1,3-glucan was added to assays. These results show that live yeast cells are efficiently ingested and hydrolyzed by A. aegypti larvae, which are able to fully-develop on a diet based exclusively on these organisms. Beta-1,3-glucanase seems to be essential for yeast lytic activity of A. aegypti larvae, which possess significant amounts of these enzyme in all parts investigated

Relação entre circunferência abdominal e pressão arterial sistólica em policiais militares do estado do Maranhão

Obesity is a non-communicable, complex and multifactorial chronic disease whose main characteristic is the excessive accumulation of fat, increasing the abdominal circumference (WC). The aim of this study was to analyze whether WC is directly related to the increase in systolic blood pressure (SBP) in military police (PM) during the operational period. The sample consisted of 415 female and male police officers. Through the physical evaluation, the body mass (kg); height (m); SBP (mmHg) and WC (cm). For data analysis, the sample was stratified into less or more than 60 months (5 years) of military service time (TTM), using Pearson's Correlation to verify the relationship between WC and SBP, with values ​​presented by mean and standard deviation. With TTM less than 60 months, there were 249 police officers aged = 29.95±4.49 years, TTM = 30.79±18.92 months, WC=90.68±9.59 cm and SBP 130.102±15.12 mmHg. With TTM greater than 60 months, there were 166 police officers aged = 44.08±6.99 years, TTM=257.95±93.86 months, WC=97.29±10.16 cm and SBP=133.97± 18.40 mmHg. There was a moderate and significant correlation between WC and PAS for officers with less than five years in the position (r=0.30; p<0.01) and low and significant for officers with more than five years in the position (r=0.27; p<0.01). The WC value does not seem to be an indication that explains the SBP variation in this population and context, suggesting that other factors are more important in this variation.A obesidade é uma doença crônica não transmissível, complexa e multifatorial que tem como característica principal o acúmulo excessivo de gordura, aumentando a circunferência abdominal (CA). O objetivo deste estudo foi analisar se a CA está diretamente relacionada ao aumento da pressão arterial sistólica (PAS) em policiais militares (PM). A amostra foi de 415 policiais dos sexos feminino e masculino. Através da avaliação física foram mensuradas a massa corporal (kg); estatura (m); PAS (mmHg) e CA (cm). Para análise dos dados houve a estratificação da amostra em menos ou mais que 60 meses (5 anos) de tempo de trabalho militar (TTM), utilizando-se da Correlação de Pearson para verificar a relação entre a CA e PAS, com valores apresentados por média e desvio padrão. Com TTM menor que 60 meses foram 249 policiais com idade = 29,95±4,49 anos, TTM=30,79±18,92 meses, CA = 90,68±9,59 cm e PAS 130,102±15,12 mmHg. Com TTM maior que 60 meses, foram 166 policiais com idade = 44,08±6,99 anos, TTM = 257,95±93,86 meses, CA=97,29±10,16 cm e PAS=133,97±18,40 mmHg. Houve correlação moderada e significativa entre CA e PAS para policiais com menos de cinco anos no cargo (r=0,30; p<0,01) e baixa e significativa para policiais com mais de cinco anos no cargo (r=0,27; p<0,01). O valor da CA não parece um indicativo que explique a variação da PAS nessa população e contexto, sugerindo que outros fatores tenham maior importância nesta variação