Abstract Background: Bitis arietans is a venomous snake found in sub-Saharan Africa and in parts of Morocco and Saudi Arabia. The envenomation is characterized by local and systemic reactions including pain, blistering, edema and tissue damage, besides hemostatic and cardiovascular disturbances, which can cause death or permanent disabilities in its victims. However, the action mechanisms that provoke these effects remain poorly understood, especially the activities of purified venom components. Therefore, in order to elucidate the molecular mechanisms that make the Bitis arietans venom so potent and harmful to human beings, this study reports the isolation and biochemical characterization of a snake venom serine protease (SVSP). Methods: Solubilized venom was fractionated by molecular exclusion chromatography and the proteolytic activity was determined using fluorescent substrates. The peaks that showed serine protease activity were determined by blocking the proteolytic activity with site-directed inhibitors. In sequence, the fraction of interest was submitted to another cycle of molecular exclusion chromatography. The purified serine protease was identified by mass spectrometry and characterized biochemically and immunochemically. Results: A serine protease of 33 kDa with fibrinogen-degrading and kinin-releasing activities was isolated, described, and designated herein as Kn-Ba. The experimental Butantan Institute antivenom produced against Bitis arietans venom inhibited the Kn-Ba activity. Conclusions: The in vitro activities of Kn-Ba can be correlated with the capacity of the venom to provoke bleeding and clotting disorders as well as hypotension, which are common symptoms presented by envenomed victims. Obtaining satisfactory Kn-Ba inhibition through the experimental antivenom is important, given the WHO's recommendation of immunotherapy in cases of human accidents with venomous snakes.

Através de uma revisão da literatura nacional e internacional sobre a formação em saúde mental dirigida para médicos que atuam na atenção primária, os autores procuram identificar referenciais pedagógicos que possam nortear metodologicamente a formação em saúde mental para essa categoria profissional no âmbito da atenção primária em saúde no Brasil.

From reviewing the national and international literature on mental health educational programs built up to primary care family doctors, the authors sought to identify pedagogical references that could help to improve local educational programs for these professionals in Brazil.

Os adoçantes são freqüentemente utilizados por mulheres em idade reprodutiva. Esta é uma revisão narrativa da literatura a respeito dos adoçantes atualmente comercializados no mercado brasileiro. Existem poucas informações sobre o uso da sacarina e ciclamato na gestação, e seus efeitos sobre o feto. Devido às limitadas informações disponíveis e ao seu potencial carcinogênico em animais, a sacarina e o ciclamato devem ser evitados durante a gestação (risco C). O aspartame tem sido extensivamente estudado em animais, sendo considerado seguro para uso na gestação (risco B), exceto para mulheres homozigóticas para fenilcetonúria (risco C). A sucralose e o acessulfame-K não são tóxicos, carcinogênico ou mutagênicos em animais, mas não existem estudos controlados em humanos. Porém, como esses dois adoçantes não são metabolizados, parece improvável que seu uso durante a gestação possa ser prejudicial (risco B). A estévia, substância derivada de uma planta nativa brasileira, não produz efeitos adversos sobre a gestação em animais, porém não existem estudos em humanos (risco B). Os agentes de corpo usados na formulação dos adoçantes (manitol, sorbitol, xilitol, eritrol, lactilol, isomalte, maltilol, lactose, frutose, maltodextrina, dextrina e açúcar invertido) são substâncias consideradas seguras para o consumo humano. Concluindo, segundo as evidências atualmente disponíveis, o aspartame, a sucralose, o acessulfame e a estévia podem ser utilizados com segurança durante a gestação.

Sweeteners are frequently used by women of reproductive age. This is a narrative review about the sweeteners currently sold in the Brazilian commerce. There is a few information on the use of saccharin and cyclamates in pregnancy and their effects on the fetus. Due to the limited information available and their carcinogenic potential in animal species, saccharin and cyclamates should be avoided during pregnancy (risk C). Aspartame has been extensively studied in animals and it is considered safe for use during pregnancy (risk B), except by women homozygous for phenylketonuria (risk C). Sucralose and acessulfame-K are not toxic, carcinogenic or mutagenic in animals, but there are no controlled studies in humans. However, since these two sweeteners are not metabolized, it is unlikely that their use during pregnancy could be harmful (risk B). Stevia, a substance extracted from a native Brazilian plant, is innocuous in animal pregnancies, but there are no controlled studies in humans (risk B). Body agents found in the composition of artificial sweeteners (mannitol, sorbitol, xylitol, erithrol, lactilol, isomalt, maltilol, lactose, fructose, maltodextrin, dextrin, and inverted sugar) are substances generally regarded as safe for human consumption. In conclusion, according to the currently available evidence, aspartame, sucralose, acessulfame-K and stevia can be safely used during pregnancy.