Sugar digestion in mosquitoes: Identification and characterization of three midgut alpha-glucosidases of the neo-tropical malaria vector Anopheles aquasalis (Diptera : Culicidae)

Dietary carbohydrates provide an important source of energy for flight, and contribute to longevity and fecundity of mosquitoes. The most common sugar mosquitoes ingest is sucrose, and digestion of this substance is carried out mainly by alpha-glucosidases. In the current work, we tested the efficiency of sucrose on Anopheles aquasalis female diet. The best longevity (days) was reached when sugar was available in the diet, whereas most only blood fed females were dead 6 days after emergence. Three alpha-glucosidase isoforms were detected in the adult female midgut, named alpha Glu1, alpha Glu2 and alpha Glu3. These are acidic alpha-glucosidases with optima pH around pH 5.5. alpha Glu1 and alpha Glu2 are present in both secreted and membrane-bound forms, whereas alpha Glu3 only in anchored to membranes. The alpha-glucosidase activity is concentrated mainly in the posterior midgut (70%), both in non-fed or 10% sucrose fed females. The single form of these a-glucosidases seemed to be similar to 70 kDa polypeptides, although alpha Glu2 is presented in >= 600 kDa self-aggregates. K, values of alpha Glu1, alpha Glu2 and alpha Glu3 differed significantly from each other, supporting the statement that three alpha-glucosidases are produced in the female midgut. Together, all data suggest that sugar is an essential component of A. aquasalis female diet. In addition, alpha-glucosidases are synthesized in the same place where sucrose is digested and absorbed, the midgut. (c) 2007 Elsevier B.V. All rights reserved.

Neo-clerodane diterpenoid, a new metalloprotease snake venom inhibitor from Baccharis trimera (Asteraceae): anti-proteolytic and anti-hemorrhagic properties

Many plants are used in traditional medicine as active agents against various effects induced by snakebite. Few attempts have been made however to identify the nature of plain natural products with anti-ophidian properties. Baccharis trimera (Less) DC (Asteraceae), known in Brazil as carqueja. has been popularly used to treat liver diseases. rheumatism. diabetes, as well as digestive, hepatic and renal disorders. The active component was identified as 7alpha-hydroxy-3,13-clerodadiene-16,15:18,19-diolide, C20H28O5, (clerodane diterpenoid, Bt-CD). We report now the anti-proteolytic and anti-hemorrhagic propenies against snake venoms of a Bt-CD inhibitor from B. trimera. Bt-CD exhibited full inhibition of hemorrhage and proteolytic activity caused by Bothrops snake venoms. The inhibitor was able to neutralize the hemorrhagic, fibrinogenolytic and caseinolytic activities of class P-I and III metalloproteases isolated from B. neuwiedi and B. jararacussu venoms. No inhibition of the coagulant activity was observed. Bt-CD also partially inhibited the edema induced by other crude venoms, metallopronteases, basic and acidic phospholipases A(2). To further elucidate the inhibitory specificity of Bt-CD against metalloproteases isolated from snake venoms, a deeper understanding of its Structure and function is necessary. Furthermore, the potential use of these inhibitors to complement anti-venom as an alternative treatment of snakebite envenomations needs to be evaluated in future Studies. (C) 2004 Elsevier B.V.. All rights reserved.

An outline of a neo-structuralist approach

Presenta un contrapunto de los enfoques neoliberal y neoestructuralista, tanto en su dimension teorica como en su aplicacion al diseno de politicas publicas.

Neo-liberalism versus neo-structuralism in Latin America

Includes bibliography

Neo-Keynesian macroeconomics as seen from the South

Includes bibliography

Neo-structuralism versus neo-liberalism in the 1990s

Presenta un contrapunto crítico en torno a los aspectos más fundamentales que distinguen a las actuales propuestas estratégicas de desarrollo de largo plazo asociadas a los enfoques neoliberal y neoestructuralista.

Neo-liberal structural reforms in Latin America: the current situation

Includes bibliography

Sixty years of ECLAC: structuralism and neo-structuralism

Includes bibliography

Do coronelismo ao neo-coronelismo: um estudo sobre a ascensão, a queda e o ressurgimento de Antônio Lorenzetti Filho

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

O humano pelo viés quantitativo: um exame do (neo)positivismo em Speridião Faissol, através da leitura de textos selecionados

Pós-graduação em Geografia - IGCE

Imperialismo e educação do campo: uma análise das políticas educacionais no estado de Rondônia a partir de 1990

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Neo-realismo e poesia: do ideológico ao estético

Pós-graduação em Estudos Literários - FCLAR