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排序方式: 共有643条查询结果,搜索用时 15 毫秒
51.
Ana T. Varela Anabela M. Simões João S. Teodoro Filipe V. Duarte Ana P. Gomes Carlos M. Palmeira Anabela P. Rolo 《Mitochondrion》2010,10(5):456-463
Indirubin-3′-oxime is an indirubin analogue that shows favorable inhibitory activity targeting glycogen synthase kinase 3β (GSK-3β). In this study, we evaluated if acute treatment with indirubin-3′-oxime (Ind) prevents hepatic ischemia/reperfusion (I/R) damage. Wistar rats were subjected to 150 min of 70% warm ischemia and 16 h of reperfusion. In the treated group 1 μM indirubin-3′-oxime was administered in the hepatic artery 30 min before ischemia. Acute treatment with Ind decreased serum alanine aminotransferase (ALT), aspartate aminotransferase (AST) and lactate dehydrogenase (LDH) levels, comparatively to I/R livers. Bax translocation to the mitochondria and cytochrome c release were higher in I/R livers. Ind treatment significantly attenuated Bax translocation and preserved mitochondrial cytochrome c content. Ind also protected mitochondria from calcium-induced mitochondrial permeability transition (MPT), as well as the decrease in state 3 mitochondrial respiration, the delay in the repolarization after a phosphorylative cycle and the decrease in ATP content caused by I/R. By addressing GSK-3β activity and phosphorylated GSK-3β at Ser9 content in liver homogenates and isolated mitochondria, data suggests that inhibition of GSK-3β by indirubin-3′-oxime prevents the increase in mitochondrial phosphorylated GSK-3β at Ser9 induced by I/R, thus correlating with MPT inhibition and preservation of cytochrome c content. Pre-treatment with indirubin-3′-oxime in conditions of hepatic I/R, protects the liver by maintaining mitochondrial function and hepatic energetic balance. 相似文献
52.
The endocrine system may be the target of different types of trauma with varied consequences. The present article discusses trauma of the hypothalamic–pituitary axes, adrenal glands, gonads, and pancreas. In addition to changes in circulating hormone levels due to direct injury to these structures, there may be an endocrine response in the context of the stress caused by the trauma. 相似文献
53.
Peña Messina E Tapia Varela R Velázquez Abunader JI Orbe Mendoza AA Velazco Arce JM 《Revista de biología tropical》2010,58(4):1577-1586
Tilapia production has increased in Aguamilpa Reservoir, in Nayarit, Mexico, in the last few years and represents a good economic activity for rural communities and the country. We determined growth parameters, mortality and reproductive aspects for 2413 specimens of blue tilapia Oreochromis aureus in this reservoir. Samples were taken monthly from July 2000 through June 2001, of which 1 371 were males and 1 042 were females. Standard length (SL) and total weight (TW) were measured in each organism. The SL/TW relationships through power models for sexes were determined. The growth parameters L infinity k, and t0 of the von Bertalanffy equation were estimated using frequency distribution of length through ELEFAN-I computer program. Finally the reproductive cycle and size of first maturity were established using morph chromatic maturity scale. The results suggested that the males and females had negative allometric growth (b < 3). Significant differences were found between SL/TW model for the sexes, suggesting separate models for males and females. Results indicate that there are no differences in growth rates between sexes; the proposed parameters were L infinity = 43.33 cm standard length, k = 0.36/year and t0 = -0.43 years. Natural and fishing mortality coefficients were 0.83/year and 1.10/year, respectively. The estimated exploitation rate (0.57/year) suggested that during the study period the fishery showed signs of overfishing. Blue tilapia reproduces year-round; the highest activity occurs from January through May and size of first maturity was 23 cm SL. We conclude that it is necessary to establish a minimum catch size in this reservoir based on the reproductive behavior of this species. 相似文献
54.
Varela Eduardo Sousa; Beasley Colin Robert; Schneider Horacio; Sampaio Iracilda; Marques-Silva Nelane Do Socorro; Tagliaro Claudia Helena 《Journal of Molluscan Studies》2007,73(3):229-234
As a result of phenotypic plasticity, the cupped oysters (Crassostrea)are difficult to identify by means of their morphology. However,molecular DNA markers are a useful means of discriminating amongthese species. Cupped oysters are one of the most widely culturedmarine invertebrates and correct species identification is importantin aquaculture. Moreover, the molecular phylogeny of the genusCrassostrea and the subfamily Crassostreinae is still not clear.In order to identify the Brazilian cupped oysters and to clarifythe phylogenetic relationships of these species, we sequenceda fragment of mitochondrial DNA (16S rRNA gene) from 120 specimenscollected at nine different sites distributed along the Braziliancoast. The results identified two native species of oyster:Crassostrea gasar, from the Amazon to the Parnaíba delta;and Crassostrea rhizophorae, from the northeast (Fortim) tothe south of Brazil. An exotic Crassostrea species, closelyrelated to Indo-Pacific Crassostrea, was found in one locationin the north of Brazil. Crassostrea showed monophyly and theAtlantic oysters are clearly separated from the Indo-Pacificcluster. (Received 30 May 2006; accepted 12 April 2007) 相似文献
55.
J A Balsa C Varela T Lucas J García-Uría B Barceló J M Sancho-Rof 《Hormones et métabolisme》2002,34(8):435-440
In this study, we have investigated the effect of combined treatment using two somatostatin analogs, lanreotide or octreotide, with bromocriptine on GH release in cultures of GH-secreting pituitary tumors. Sixteen acromegalic patients were included in the study. All patients had been treated with lanreotide prior to the surgery. Five patients (31.2 %) reached GH levels below 2.0 microg/l and normal IGF-I levels according to age and sex after lanreotide treatment. A positive correlation was observed between the lanreotide-induced inhibition of GH release in vitro and serum GH decrease after lanreotide treatment (r = 0.52; p = 0.03). Combined treatment significantly inhibited GH release in vitro in 8 of the 16 tumors (50 %). However, only 5 (31.2 %) of the respective patients had been resistant to presurgical treatment with lanreotide. Three of these 5 patients (18.7 %) responded to a BC concentration similar to that achieved with therapeutic doses, and in 2 patients only when a pharmacological dose of BC was used in the combined treatment. The additive effect was observed with the combination of lanreotide and BC in 6 tumors and with octreotide and BC in 3. Only one tumor showed simultaneous response to both types of combination. These results suggest that the additive effect under the combined treatment might be found between 18 and 30 % of patients who are resistant to these drugs, and that different combinations of somatostatin analogs and dopamine agonists should be tested in resistant patients. 相似文献
56.
57.
Tuning immune tolerance with vasoactive intestinal peptide: a new therapeutic approach for immune disorders 总被引:1,自引:0,他引:1
The induction of immune tolerance is essential for the maintenance of immune homeostasis and to limit the occurrence of exacerbated inflammatory and autoimmune conditions. Multiple mechanisms act together to ensure self-tolerance, including central clonal deletion, cytokine deviation and induction of regulatory T cells. Identifying the factors that regulate these processes is crucial for the development of new therapies of autoimmune diseases and transplantation. The vasoactive intestinal peptide (VIP) is a well-characterized endogenous anti-inflammatory neuropeptide with therapeutic potential for a variety of immune disorders. Here, we examine the latest research findings, which indicate that VIP participates in maintaining immune tolerance in two distinct ways: by regulating the balance between pro-inflammatory and anti-inflammatory factors, and by inducing the emergence of regulatory T cells with suppressive activity against autoreactive T-cell effectors. 相似文献
58.
Iterative applications are known to run as slow as their slowest computational component. This paper introduces malleability, a new dynamic reconfiguration strategy to overcome this limitation. Malleability is the ability to dynamically change the
data size and number of computational entities in an application. Malleability can be used by middleware to autonomously reconfigure
an application in response to dynamic changes in resource availability in an architecture-aware manner, allowing applications
to optimize the use of multiple processors and diverse memory hierarchies in heterogeneous environments.
The modular Internet Operating System (IOS) was extended to reconfigure applications autonomously using malleability. Two
different iterative applications were made malleable. The first is used in astronomical modeling, and representative of maximum-likelihood
applications was made malleable in the SALSA programming language. The second models the diffusion of heat over a two dimensional
object, and is representative of applications such as partial differential equations and some types of distributed simulations.
Versions of the heat application were made malleable both in SALSA and MPI. Algorithms for concurrent data redistribution
are given for each type of application. Results show that using malleability for reconfiguration is 10 to 100 times faster
on the tested environments. The algorithms are also shown to be highly scalable with respect to the quantity of data involved.
While previous work has shown the utility of dynamically reconfigurable applications using only computational component migration,
malleability is shown to provide up to a 15% speedup over component migration alone on a dynamic cluster environment.
This work is part of an ongoing research effort to enable applications to be highly reconfigurable and autonomously modifiable
by middleware in order to efficiently utilize distributed environments. Grid computing environments are becoming increasingly
heterogeneous and dynamic, placing new demands on applications’ adaptive behavior. This work shows that malleability is a
key aspect in enabling effective dynamic reconfiguration of iterative applications in these environments.
相似文献
Carlos A. VarelaEmail: |
59.
Claudio Hidalgo-Cantabrana Borja Sánchez Pablo álvarez-Martín Patricia López Noelia Martínez-álvarez Michele Delley Marc Martí Encarna Varela Ana Suárez María Antolín Francisco Guarner Bernard Berger Patricia Ruas-Madiedo Abelardo Margolles 《Applied and environmental microbiology》2015,81(23):7960-7968
Exopolysaccharides (EPS) are extracellular carbohydrate polymers synthesized by a large variety of bacteria. Their physiological functions have been extensively studied, but many of their roles have not yet been elucidated. We have sequenced the genomes of two isogenic strains of Bifidobacterium animalis subsp. lactis that differ in their EPS-producing phenotype. The original strain displays a nonmucoid appearance, and the mutant derived thereof has acquired a mucoid phenotype. The sequence analysis of their genomes revealed a nonsynonymous mutation in the gene Balat_1410, putatively involved in the elongation of the EPS chain. By comparing a strain from which this gene had been deleted with strains containing the wild-type and mutated genes, we were able to show that each strain displays different cell surface characteristics. The mucoid EPS synthesized by the strain harboring the mutation in Balat_1410 provided higher resistance to gastrointestinal conditions and increased the capability for adhesion to human enterocytes. In addition, the cytokine profiles of human peripheral blood mononuclear cells and ex vivo colon tissues suggest that the mucoid strain could have higher anti-inflammatory activity. Our findings provide relevant data on the function of Balat_1410 and reveal that the mucoid phenotype is able to alter some of the most relevant functional properties of the cells. 相似文献
60.
The galactose‐binding lectin isolated from Bauhinia bauhinioides Mart seeds inhibits neutrophil rolling and adhesion via primary cytokines
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Deysen Kerlla Fernandes Bezerra Girão Benildo Sousa Cavada Alana de Freitas Pires Timna Varela Martins Álvaro Xavier Franco Cecília Mendes Morais Kyria Santiago do Nascimento Plinio Delatorre Helton Colares da Silva Celso Shiniti Nagano Ana Maria Sampaio Assreuy Pedro Marcos Gomes Soares 《Journal of molecular recognition : JMR》2015,28(5):285-292
In this study, the amino acid sequence and anti‐inflammatory effect of Bauhinia bauhinioides (BBL) lectin were evaluated. Tandem mass spectrometry revealed that BBL possesses 86 amino acid residues. BBL (1 mg/kg) intravenously injected in rats 30 min prior to inflammatory stimuli inhibited the cellular edema induced by carrageenan in only the second phase (21% – 3 h, 19% – 4 h) and did not alter the osmotic edema induced by dextran. BBL also inhibited carrageenan peritoneal neutrophil migration (51%), leukocyte rolling (58%) and adhesion (68%) and the neutrophil migration induced by TNF‐α (64%). These effects were reversed by the association of BBL with galactose, demonstrating that the carbohydrate‐binding domain is essential for lectin activity. In addition, BBL reduced myeloperoxidase activity (84%) and TNF‐α (68%) and IL1‐β (47%) levels. In conclusion, the present investigation demonstrated that BBL contains highly homologous isolectins, resulting in a total of 86 amino acid residues, and exhibits anti‐inflammatory activity by inhibiting neutrophil migration by reducing TNF‐α and IL1‐β levels via the lectin domain. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献