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Many studies have focused on identifying the signaling pathway by which addition of glucose triggers post-translational activation of the plasma membrane H+-ATPase in yeast. They have revealed that calcium signaling is involved in the regulatory pathway, supported for instance by the phenotype of mutants inARG82 that encodes an inositol kinase that phosphorylates inositol triphosphate (IP3). Strong glucose-induced calcium signaling, and high glucose-induced plasma membrane H+-ATPase activation have been observed in a specific yeast strain with the PJ genetic background. In this study, we have applied pooled-segregant whole genome sequencing, QTL analysis and a new bioinformatics methodology for determining SNP frequencies to identify the cause of this discrepancy and possibly new components of the signaling pathway. This has led to the identification of an STT4 allele with 6 missense mutations as a major causative allele, further supported by the observation that deletion of STT4 in the inferior parent caused a similar increase in glucose-induced plasma membrane H+-ATPase activation. However, the effect on calcium signaling was different indicating the presence of additional relevant genetic differences between the superior and reference strains. Our results suggest that phosphatidylinositol-4-phosphate might play a role in the glucose-induced activation of plasma membrane H+-ATPase by controlling intracellular calcium release through the modulation of the activity of phospholipase C.

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Standards of care for human visceral leishmaniasis (VL) are based on drugs used parenterally, and oral treatment options are urgently needed. In the present study, a repurposing strategy was used associating tamoxifen (TMX) with polyethylene glycol-block-polylactide nanocapsules (NC) and its anti-leishmanial efficacy was reported in vivo. Stable surface modified-NC (5 mg/mL of TMX) exhibited 200 nm in size, +42 mV of zeta potential, and 98% encapsulation efficiency. Atomic force microscopy evidenced core-shell-NC. Treatment with TMX-NC reduced parasite-DNA quantified in liver and spleen compared to free-TMX; and provided a similar reduction of parasite burden compared with meglumine antimoniate in mice and hamster models. Image-guided biodistribution showed accumulation of NC in liver and spleen after 30 min post-administration. TMX-NC reduced the number of liver granulomas and restored the aspect of capsules and trabeculae in the spleen of infected animals. TMX-NC was tested for the first time against VL models, indicating a promising formulation for oral treatment.

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Strains of the same Leishmania parasite species, isolated from different host organisms, may exhibit unique infection profiles and induce a change in the expression of microRNAs among host macrophages and in model host mice. MicroRNAs (MiR) are endogenous molecules of about 22 nucleotides that are involved in many regulatory processes, including the vertebrate host immune response. In this respect, the infectivity and susceptibility to antimonials of two L. infantum strains, BH46, isolated from human, and OP46, isolated from symptomatic dog, were characterized in J774 macrophages and BALB/c mice. Parasite burden was assessed in the liver, spleen, and bone marrow using the serial limiting dilution technique. A higher parasite burden was observed in the spleen and bone marrow of animals infected with OP46 compared to BH46 strain. Our results also showed that OP46 was less susceptible to the antimonials. In addition, miR-122 and miR-155 expression was evaluated in the liver and J774 macrophages, and in spleens from infected animals, respectively. An increase was observed in the expression of miR-155 in J774 macrophages infected with both strains compared to uninfected cells, with a higher expression in cells infected with OP46. However, no difference in the expression of miR-122 and miR-155 was observed in the infected animals. Thus, this study shows that OP46 was more infective for mice, it caused a higher increase in miR-155 expression in infected macrophages and was less susceptible to the antimonials evaluated. These data suggest that alteration in miR-155 level likely plays a role in regulating the response to L. infantum.

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Estudo qualitativo no qual os sujeitos foram mães/acompanhantes das crianças hospitalizadas na Unidade de Internação Pediátrica do Hospital das Clínicas da Faculdade de Medicina de Botucatu, da Universidade Estadual Paulista. O objetivo com o estudo foi refletir sobre as vantagens, desvantagens e dificuldades do brincar no ambiente hospitalar. Foram realizadas 14 entrevistas gravadas em fita cassete, após o consentimento dos entrevistados, sendo que, posteriormente, realizou-se a interpretação, a análise e a preparação dos resultados de pesquisa. De modo geral, os dados mostraram que as mães percebem o brincar no ambiente hospitalar como uma forma importante para a distração e a alegria da criança durante a internação.

This is a qualitative study whose subjects were mothers or companions of children admitted at the Pediatric Unit ofthe public Medical School of Botucatu, SP. It aims to consider the advantages, disadvantages and difficulties of children who play in the hospital. After consent, fourteen interviews were recorded, studied and then analyzed. Results indicate that, in general, mothers feel that playing in the hospital is an important way to amuse and bring joy to their children during internment.

Se trata de un estudio cualitativo cuyos sujetos eran las madres/acompañantes de niños hospitalizados en la unidadde la internación de pediátrica del Hospital de Clínicas de la Facultad de Medicina de Botucatu de la Universidad Estatal Paulista. Teniendo como objetivo reflexionar acerca de las ventajas, desventajas y dificultades de jugar en el ambiente hospitalario. Con el consentimiento de los entrevistados se realizaron catorce entrevistas grabadas en cinta cassette y después la interpretación, análisis y preparación de los resultados de la investigación. En general, los datos demostraron que las madres sienten que jugar en el hospital es una forma importante para distraer y traer alegría alos niños durante su internación.

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