2,254 research outputs found

    La mortalidad de las camadas

    Get PDF

    Annotated checklist and illustrated key to braconid parasitoids (Hymenoptera, Braconidae) of economically important fruit flies (Diptera, Tephritidae) in Brazil

    Get PDF
    The braconid parasitoids of fruit-infesting flies have been more intensively studied from the middle to late 1990s, when taxonomic research was restarted in Brazil. At the same time, efforts toward the biological control of fruit flies intensified, and an exotic species, Diachasmimorpha longicaudata, was introduced. In the decade 2010, another exotic species, Fopius arisanus, was introduced, and two new species of Doryctobracon were described. Currently, 12 species of braconids from the subfamilies Alysiinae (two species) and Opiinae (10 species) are associated with fruit flies of economic importance in Brazil, two of which are introduced species. More than half of the species belong to the genus Doryctobracon, with D. areolatus (Szépligeti) the most widely distributed species in Brazil.Fil: Fidelis Marinho, Claudia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro de Investigaciones y Transferencia de Catamarca. Universidad Nacional de Catamarca. Centro de Investigaciones y Transferencia de Catamarca; ArgentinaFil: Costa, Valmir A.. Universidade Estadual de Campinas; BrasilFil: Zucchi, Roberto A.. Universidade do Sao Paulo. Escola Superior de Agricultura Luiz de Queiroz; Brasi

    An update on vitamin d metabolism

    Get PDF
    Vitamin D is a steroid hormone classically involved in the calcium metabolism and bone homeostasis. Recently, new and interesting aspects of vitamin D metabolism has been elucidated, namely the special role of the skin, the metabolic control of liver hydroxylase CYP2R1, the specificity of 1α-hydroxylase in different tissues and cell types and the genomic, non-genomic and epigenomic effects of vitamin D receptor, which will be addressed in the present review. Moreover, in the last decades, several extraskeletal effects which can be attributed to vitamin D have been shown. These beneficial effects will be here summarized, focusing on the immune system and cardiovascular system

    Update on 3-iodothyronamine and its neurological and metabolic actions

    Get PDF
    3-iodothyronamine (T1AM) is an endogenous amine, that has been detected in many rodent tissues, and in human blood. It has been hypothesized to derive from thyroid hormone metabolism, but this hypothesis still requires validation. T1AM is not a ligand for nuclear thyroid hormone receptors, but stimulates with nanomolar affinity trace amine-associated receptor 1 (TAAR1), a G protein-coupled membrane receptor. With a lower affinity it interacts with alpha2A adrenergic receptors. Additional targets are represented by apolipoprotein B100, mitochondrial ATP synthase, and membrane monoamine transporters, but the functional relevance of these interactions is still uncertain. Among the effects reported after administration of exogenous T1AM to experimental animals, metabolic and neurological responses deserve special attention, because they were obtained at low dosages, which increased endogenous tissue concentration by about one order of magnitude. Systemic T1AM administration favored fatty acid over glucose catabolism, increased ketogenesis and increased blood glucose. Similar responses were elicited by intracerebral infusion, which inhibited insulin secretion and stimulated glucagon secretion. However, T1AM administration increased ketogenesis and gluconeogenesis also in hepatic cell lines and in perfused liver preparations, providing evidence for a peripheral action, as well. In the central nervous system, T1AM behaved as a neuromodulator, affecting adrenergic and/or histaminergic neurons. Intracerebral T1AM administration favored learning and memory, modulated sleep and feeding, and decreased the pain threshold. In conclusion T1AM should be considered as a component of thyroid hormone signaling and might play a significant physiological and/or pathophysiological role. T1AM analogs have already been synthetized and their therapeutical potential is currently under investigation. 3-iodothyronamine (T1AM) is a biogenic amine whose structure is closely related to that of thyroid hormone (3,5,3′-triiodothyronine, or T3). The differences with T3 are the absence of the carboxylate group and the substitution of iodine with hydrogen in 5 and 3′ positions (Figure 1). In this paper we will review the evidence supporting the hypothesis that T1AM is a chemical messenger, namely that it is an endogenous substance able to interact with specific receptors producing significant functional effects. Special emphasis will be placed on neurological and metabolic effects, which are likely to have physiological and pathophysiological importance

    Androgen deprivation therapy (castration therapy) and pedophilia: What's new

    Get PDF
    Andrology is a constantly evolving discipline, embracing social problems like pedophilia and its pharmacological treatment. With regard to chemical castration, the andrologist may perform an important role as part of a team of specialists. At present, no knowledge is available regarding hormonal, chromosomal or genetic alterations involved in pedophilia. International legislation primarily aims to defend childhood, but does not provide for compulsory treatment. We reviewed international literature that, at present, only comprises a few reports on research concerning androgen deprivation. Most of these refer to the use of leuprolide acetate, rather than medroxyprogesterone and cyproterone acetate, which present a larger number of side effects. Current opinions on chemical castration for pedophilia are discordant. Some surveys confirm that therapy reduces sexual thoughts and fantasies, especially in recidivism. On the other hand, some authors report that chemical castration does not modify the pedophile's personality. In our opinion, once existing legislation has changed, andrologists could play a significant role in the selection of patients to receive androgen deprivation therapy, due in part to their knowledge about its action and side effects

    First Record of the Fruit Fly Parasitoid Doryctobracon crawfordi (Viereck) (Hymenoptera: Braconidae) in Brazil.

    Get PDF
    Doryctobracon crawfordi (Viereck) was recorded in the states of Amapá and Roraima, Brazil. This is also the first time that this parasitoid is associated with Anastrepha atrigona Hendel from Geissospermum argenteum

    Games of Make-Believe and Factual Information

    Get PDF
    corecore