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1.
An Acad Bras Cienc ; 93(suppl 4): e20210222, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34909827

RESUMO

This study evaluated the ability of resistance training (RT) of moderate intensity to promote vascular changes in insulin-induced vasodilation in healthy animals. Wistar rats were divided into two groups: control (CON) and trained (eight weeks of training, performing 3 sets with 10 repetitions at 60% of maximum intensity). Forty-eight hours after the last session of the RT, the animals were sacrificed and vascular reactivity to insulin in the absence and presence of LY294002 (phosphatidylinositol 3-kinase inhibitors (PI3K), L-NAME (nitric oxide synthase (NOS) inhibitors) and BQ123 (endothelin A antagonist (ET-A) receptor). In addition, phenylephrine (Phe)-induced vasoconstriction in the absence and presence of L-NAME was also evaluated. The RT group showed greater vasodilation in maximal response compared to the CON group. After PI3K inhibition, vasodilation was reduced in both groups. However, when the NOS participation was evaluated, the RT group showed contraction in relation to the CON group, which was abolished by BQ123. In addition, the RT group had an increase in nitrite levels compared to the CON group. When the Phe response was evaluated, there was a reduction in tension in the RT group compared to the CON group. The results suggest that RT improves vascular reactivity.


Assuntos
Treinamento Resistido , Vasodilatação , Animais , Humanos , Insulina , Artérias Mesentéricas , Óxido Nítrico , Fosfatidilinositol 3-Quinases , Inibidores de Fosfoinositídeo-3 Quinase , Ratos , Ratos Wistar
2.
ACS Appl Mater Interfaces ; 13(22): 26001-26012, 2021 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-34043905

RESUMO

Acetaldehyde is an important chemical commodity and a building block for producing several other high-value products in the chemical industry. This has motivated the search for suitable, efficient, stable, and selective catalysts, as well as renewable raw materials such as ethanol. In this work, supported copper catalysts were prepared from CuZnAl layered double hydroxides (LDHs) with different copper contents (5, 10, and 20 wt %) for application in the ethanol dehydrogenation reaction (EDR). The samples were thoroughly characterized by a series of techniques, which allowed for analysis of all of the copper and zinc species involved in the different catalyst preparation steps and during the EDR. The results obtained by in situ quick extended X-ray absorption fine structure (EXAFS) measurements, combined with multivariate data analysis, showed that the copper content in the pristine LDH influenced the phase composition of the mixed oxide support, which consequently affected the dispersion of copper nanoparticles. The higher the copper content, the higher are the ZnAl2O4 and zinc tetrahedral prenuclei (TPN) contents, to the detriment of the ZnO content. All the samples showed high selectivity (>97%) and stability in the catalytic reactions at 300 and 350 °C, with no observed deactivation during 6 h on-stream. Although the samples with lower copper content presented higher copper dispersion and reactivity, the sample containing 20 wt % of copper outperformed the others, with greater conversion and higher activity toward acetaldehyde.

3.
Sensors (Basel) ; 20(1)2019 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-31861511

RESUMO

The mobile ad hoc communication in highly dynamic scenarios, like urban evacuations or search-and-rescue processes, plays a key role in coordinating the activities performed by the participants. Particularly, counting on message routing enhances the communication capability among these actors. Given the high dynamism of these networks and their low bandwidth, having mechanisms to predict the network topology offers several potential advantages; e.g., to reduce the number of topology propagation messages delivered through the network, the consumption of resources in the nodes and the amount of redundant retransmissions. Most strategies reported in the literature to perform these predictions are limited to support high mobility, consume a large amount of resources or require training. In order to contribute towards addressing that challenge, this paper presents a history-based predictor (HBP), which is a prediction strategy based on the assumption that some topological changes in these networks have happened before in the past, therefore, the predictor can take advantage of these patterns following a simple and low-cost approach. The article extends a previous proposal of the authors and evaluates its impact in highly mobile scenarios through the implementation of a real predictor for the optimized link state routing (OLSR) protocol. The use of this predictor, named OLSR-HBP, shows a reduction of 40-55% of topology propagation messages compared to the regular OLSR protocol. Moreover, the use of this predictor has a low cost in terms of CPU and memory consumption, and it can also be used with other routing protocols.

4.
J. Bras. Patol. Med. Lab. (Online) ; 55(6): 693-704, Nov.-Dec. 2019.
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1090752

RESUMO

ABSTRACT Chagas disease (CD) is a neglected endemic disease. Its classic form of transmission occurs through hematophagous triatomine insects. Its classic form of transmission occurs through hematophagous triatomine insects. There are cases of the disease in non-endemic regions that occur through alternative transmissions, as this possibility also exists. The aim of this study was to report a case among members of a same family (born and resident in Taquarituba, São Paulo, Brazil) diagnosed with CD. The family matriarch lived in a mud house in the countryside and reported contact with the triatomine during childhood. Two grown-up children are also seroreactive; both reported not having contact with the insect as children. Medical record analyzes and new laboratory tests were performed. Clinical history and recent tests have confirmed positivity for CD in the matriarch and her grown-up children. Parasitological techniques have shown negative results, evidencing that they are in the chronic form of the disease. Congenital transmission may have occurred between them, as well as the possibility of vector transmission by secondary species cannot be ruled out, since the patients come from a municipality considered endemic for CD in the past.


RESUMEN La enfermedadde Chagas (EC) es una infección endémica que ha sido descuidada. Su forma clásica de transmisión ocurre mediante insectos triatominos hematófagos. Hay casos de la enfermedad en regiones no endémicas que ocurrieron por vías alternativas de transmisión, puesto que también hay esa posibilidad. El objetivo de este estudio fue reportar un caso de miembros de una misma familia diagnosticados con EC. La matriarca de la familia vivía en una casa hecha de barro en la zona ruraly reportó contacto con el triatomino en su infancia. Dos hijosson también sero-reactivos, pero no reportaron contacto con el insecto cuando eran ninos. Se hicieron análisis de historial médico y nuevaspruebas de laboratorio. El histórico clínico y laspruebas recientes confirmaran la positividad para EC, tanto en la madre como en los hijos. Las técnicasparasitológicas demostraron resultados negativos, comprobando la forma crónica de la enfermedad. Transmisión congénitapuede haber ocurrido entre ellos, así como no se puede descartar la posibilidad de ocurrencia de transmisión vectorial por especies secundarias, ya que los pacientes proceden de un municipio que fue considerado endémico para EC en el pasado.


RESUMO A doença de Chagas (DC) é uma enfermidade endêmica negligenciada. Sua forma clássica de transmissão ocorre por meio de insetos triatomíneos hematófagos. Há casos da doença em regiões não endêmicas ocorridos por transmissões alternativas, uma vez que também existe essa possibilidade. O objetivo deste estudo foi relatar um caso de membros da mesma família (natural e residente em Taquarituba, São Paulo, Brasil) diagnosticados com DC. A matriarca da família morava em uma casa de barro na zona rural e relatou contato com o triatomíneo na infância. Dois filhos também são sororreagentes; ambos relataram não terem tido contato com o inseto quando crianças. Análises de prontuário e novos testes laboratoriais foram feitos. O histórico clínico e os recentes exames confirmaram a positividade para DC, tanto na mãe quanto nos filhos. As técnicas parasitológicas demonstraram resultados negativos, constatando forma crônica da doença. Transmissão congênita pode ter ocorrido entre eles, assim como também não se pode descartar a possibilidade de ocorrência de transmissão vetorial por espécies secundárias, visto que os pacientes são oriundos de um município considerado endêmico para DC no passado.

5.
PLoS One ; 12(5): e0178162, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28542513

RESUMO

In Escherichia coli, the ATP-Binding Cassette transporter for phosphate is encoded by the pstSCAB operon. PstS is the periplasmic component responsible for affinity and specificity of the system and has also been related to a regulatory role and chemotaxis during depletion of phosphate. Xanthomonas citri has two phosphate-binding proteins: PstS and PhoX, which are differentially expressed under phosphate limitation. In this work, we focused on PhoX characterization and comparison with PstS. The PhoX three-dimensional structure was solved in a closed conformation with a phosphate engulfed in the binding site pocket between two domains. Comparison between PhoX and PstS revealed that they originated from gene duplication, but despite their similarities they show significant differences in the region that interacts with the permeases.


Assuntos
Proteínas de Bactérias/química , Regulação Bacteriana da Expressão Gênica , Proteínas de Ligação a Fosfato/química , Regulon/genética , Xanthomonas/genética , Sequência de Aminoácidos , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Cristalografia por Raios X , Proteínas de Ligação a Fosfato/genética , Proteínas de Ligação a Fosfato/metabolismo , Fosfatos/metabolismo , Conformação Proteica , Alinhamento de Sequência , Xanthomonas/crescimento & desenvolvimento , Xanthomonas/metabolismo
6.
Genetica ; 144(4): 375-83, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27220863

RESUMO

The great diversity of Camponotus, high levels of geographic, intraspecific and morphological variation common to most species of this genus make the determination of the interspecific limits of Camponotus a complex task. The Cytochrome c oxidase 1 (COI) gene was sequenced in this study to serve as an auxiliary tool in the identification of two taxa of Camponotus thought to be morphologically similar. Additionally, characteristics related to nesting were described. Five to fifteen workers from twenty-one colonies were analyzed, collected from twigs scattered in the leaf litter and from trees located in different regions of Brazil. Phylogenetic reconstructions, haplotype network, and nesting strategies confirmed the existence of two species and that they correspond to Camponotus senex and Camponotus textor. Our results emphasize that the COI can be used as an additional tool for the identification of morphologically similar Camponotus species.


Assuntos
Formigas/fisiologia , Complexo IV da Cadeia de Transporte de Elétrons/genética , Comportamento de Nidação , Animais , Formigas/classificação , Brasil , Genes Mitocondriais , Geografia , Haplótipos , Filogenia
7.
Mol Ecol ; 24(23): 5957-75, 2015 12.
Artigo em Inglês | MEDLINE | ID: mdl-26502084

RESUMO

Two main hypotheses have been proposed to explain the diversification of the Caatinga biota. The riverine barrier hypothesis (RBH) claims that the São Francisco River (SFR) is a major biogeographic barrier to gene flow. The Pleistocene climatic fluctuation hypothesis (PCH) states that gene flow, geographic genetic structure and demographic signatures on endemic Caatinga taxa were influenced by Quaternary climate fluctuation cycles. Herein, we analyse genetic diversity and structure, phylogeographic history, and diversification of a widespread Caatinga lizard (Cnemidophorus ocellifer) based on large geographical sampling for multiple loci to test the predictions derived from the RBH and PCH. We inferred two well-delimited lineages (Northeast and Southwest) that have diverged along the Cerrado-Caatinga border during the Mid-Late Miocene (6-14 Ma) despite the presence of gene flow. We reject both major hypotheses proposed to explain diversification in the Caatinga. Surprisingly, our results revealed a striking complex diversification pattern where the Northeast lineage originated as a founder effect from a few individuals located along the edge of the Southwest lineage that eventually expanded throughout the Caatinga. The Southwest lineage is more diverse, older and associated with the Cerrado-Caatinga boundaries. Finally, we suggest that C. ocellifer from the Caatinga is composed of two distinct species. Our data support speciation in the presence of gene flow and highlight the role of environmental gradients in the diversification process.


Assuntos
Ecossistema , Fluxo Gênico , Especiação Genética , Lagartos/genética , Animais , Teorema de Bayes , Brasil , Núcleo Celular/genética , DNA Mitocondrial/genética , Variação Genética , Haplótipos , Lagartos/classificação , Modelos Genéticos , Dados de Sequência Molecular , Filogenia , Filogeografia , Análise de Sequência de DNA
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