Publications by authors named "Rosas L"

The evolution of male-sterile individuals in hermaphroditic species represents the first step in the evolution of sex specialization. For male-sterile individuals to persist they must have some fitness advantage that compensates for their loss of the male function. Female fecundity also depends on environmental factors as those determining the likelihood of pollination and fertilization.

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Previous studies have demonstrated that Leishmania donovani attenuates STAT1-mediated signaling in macrophages; however it is not clear whether other species of Leishmania, which cause cutaneous disease, also interfere with macrophage IFN-gamma signaling. Therefore, we determined the effect of Leishmania major and Leishmania mexicana infection on STAT1-mediated IFN-gamma signaling pathway in J774A.1 and RAW264.

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To determine the role of STAT4-dependent Th1 responses in the regulation of immunity to the helminth parasite Taenia crassiceps, we monitored infections with this parasite in resistant mice lacking the STAT4 gene. While T. crassiceps-infected STAT4(+/+) mice rapidly resolved the infection, STAT4(-/-) mice were highly susceptible to infection and displayed large parasite loads.

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We used Daphnia magna bioassays to determine the LC(50) and the effects on the heart of the cardioactive drugs ouabain, verapamil, metaproterenol and metoprolol. Distinctions were made between the pharmacological and toxicological effects of these drugs and the adequacy of physicochemical characteristics of its habitat (reconstituted water). Video microscopy and digital image processing were used to study the pharmacological effects on the heart.

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Although STAT1-dependent signaling mediates biological functions of IFN-alpha/beta and IFN-gamma, recent reports indicate that STAT1-independent IFN signaling also regulates expression of several genes. To determine the roles of STAT1-dependent and -independent IFN signaling in the regulation of immunity during cutaneous leishmaniasis, we studied the course of Leishmania major infection in resistant C57BL/6 mice lacking the STAT1 gene. While L.

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CC chemokine receptor 1 (CCR1) is expressed on the surfaces of monocytes, lymphocytes, neutrophils and eosinophils. CC chemokine receptor 1 not only regulates leucocyte chemotaxis, but also plays a role in the regulation of Th1/Th2 cytokine responses. To determine the role of CCR1 in regulation of immune response during Leishmania major infection, we analysed the course of cutaneous L.

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To determine the role of endogenous migration inhibitory factor (MIF) in regulation of immune response during murine cysticercosis caused by the helminth parasite Taenia crassiceps, we analyzed the course of T. crassiceps infection in MIF(-/-) BALB/c mice. MIF(-/-) mice were highly susceptible to T.

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Purpose: Colonic bleeding has historically been controlled by the use of localization procedures and surgery. Since our initial experience with superselective embolization of colonic bleeding, it has become our preferred method for the control of lower gastrointestinal hemorrhage. This follow-up study evaluates the Hartford Hospital experience using angiographic methods as the primary modality for the treatment of colonic bleeding.

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Recent studies have demonstrated that IL-13 mediates susceptibility to cutaneous L. major infection via IL-4-independent pathway. To determine whether IL-13 also plays a similar role in pathogenesis of cutaneous L.

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Pituitary adenoma, familiar type, with apparent affection over the involved somatomammotropin of secretion of growth hormone and prolactin, with dominant autosomic transmission, is described for the first time. It was seen that a couple of members without demonstrable tumour, showed clinical data (phenotype) of acromegaly. On investigation of histocompatibility antigens it was observed that the patients with tumour and other symptomatic ones, but without tumour, shared the same haplotypes, and so is very possible that investigation of HLA antigens in patients with pituitary tumour, contributes to better identify its nature and frequency.

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