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101.
Invariant and noninvariant natural killer T cells exert opposite regulatory functions on the immune response during murine schistosomiasis 下载免费PDF全文
Mallevaey T Fontaine J Breuilh L Paget C Castro-Keller A Vendeville C Capron M Leite-de-Moraes M Trottein F Faveeuw C 《Infection and immunity》2007,75(5):2171-2180
CD1d-restricted natural killer T (NKT) cells represent a heterogeneous population of innate memory immune cells expressing both NK and T-cell markers distributed into two major subsets, i.e., invariant NKT (iNKT) cells, which express exclusively an invariant T-cell receptor (TCR) alpha chain (Valpha14Jalpha18 in mice), and non-iNKT cells, which express more diverse TCRs. NKT cells quickly produce Th1- and/or Th2-type cytokines following stimulation with glycolipid antigen (Ag) and, through this property, play potent immunoregulatory roles in autoimmune diseases, cancer, and infection. No study has addressed the role of NKT cells in metazoan parasite infections so far. We show that during murine schistosomiasis, the apparent frequency of both iNKT cells and non-iNKT cells decreased in the spleen as early as 3 weeks postinfection (p.i.) and that both populations expressed a greater amount of the activation marker CD69 at 6 weeks p.i., suggesting an activated phenotype. Two different NKT-cell-deficient mouse models, namely, TCR Jalpha18-/- (exclusively deficient in iNKT cells) and CD1d-/- (deficient in both iNKT and non-iNKT cells) mice, were used to explore the implication of these subsets in infection. We show that whereas both iNKT and non-iNKT cells do not have a major impact on the immune response during the early phase (1 and 4 weeks) of infection, they exert important, although opposite, effects on the immune response during the acute phase of the disease (7 and 12 weeks), after schistosome egg production. Indeed, iNKT cells contribute to Th1 cell differentiation whereas non-iNKT cells might be mostly implicated in Th2 cell differentiation in response to parasite Ag. Our findings suggest, for the first time, that helminths activate both iNKT and non-iNKT cells in vivo, enabling them to differentially influence the Th1/Th2 balance of the immune response. 相似文献
102.
de Moraes Pantaleão S Alcântara AV Hora Alves Jdo P Pavanin LA Graf U de Rezende AA Bueno Valadares BL Fragiorge EJ de Souza NC Guterres Zda R Spanó MA 《Environmental and molecular mutagenesis》2007,48(2):96-105
The Drosophila melanogaster somatic mutation and recombination test (SMART) was used to assess the genotoxicity of surface (S) and bottom (B) water and sediment samples collected from Sites 1 and 2 on the Japaratuba River (Sergipe, Brazil), an area impacted by a petrochemical industrial complex that indirectly discharges treated effluent (produced water) into the river. The genotoxicity tests were performed in standard (ST) cross and high bioactivation (HB) cross flies and were conducted on samples taken in March (dry season) and in July (rainy season) of 2003. Mutant spot frequencies found in treatments with unprocessed water and sediment samples from the test sites were compared with the frequencies observed for similar samples taken from a clean reference site (the Jacarecica River in Sergipe, Brazil) and those of negative (ultrapure water) controls. While samples from the Japaratuba River generally produced greater responses than those from the Jacarecica River, positive responses were detected for both the test and reference site samples. All the water samples collected in March 2003 were genotoxic. In July 2003, the positive responses were restricted to water samples collected from Sites 1 B and 2 S in the ST cross. The genotoxicity of the water samples was due to mitotic recombination, and the samples produced similar genotoxic responses in ST and HB flies. The spot frequencies found in the July water samples were considerably lower than those for the March water samples, suggesting a seasonal effect. The only sediment samples that were genotoxic were from Site 1 (March and July) and from the Jacarecica River (March). The genotoxins in these samples produced both somatic mutation (limited to the Site 1 sample in HB flies) and recombination. The results of this study indicate that samples from both the Japaratuba and Jacarecica Rivers were genotoxic, with the most consistently positive responses detected with Site 1 samples, the site closest to the putative pollution source. 相似文献
103.
Adalberto Sperb Rubin Douglas Zaione Nascimento Letícia Sanchez Guilherme Watte Arthur Rodrigo Ronconi Holand Derrick Alexandre Fassbind José Jesus Camargo 《Jornal brasileiro de pneumologia》2015,41(4):299-304
Objective:
To evaluate the changes in lung function in the first year after single lung transplantation in patients with idiopathic pulmonary fibrosis (IPF).Methods:
We retrospectively evaluated patients with IPF who underwent single lung transplantation between January of 2006 and December of 2012, reviewing the changes in the lung function occurring during the first year after the procedure.Results:
Of the 218 patients undergoing lung transplantation during the study period, 79 (36.2%) had IPF. Of those 79 patients, 24 (30%) died, and 11 (14%) did not undergo spirometry at the end of the first year. Of the 44 patients included in the study, 29 (66%) were men. The mean age of the patients was 57 years. Before transplantation, mean FVC, FEV1, and FEV1/FVC ratio were 1.78 L (50% of predicted), 1.48 L (52% of predicted), and 83%, respectively. In the first month after transplantation, there was a mean increase of 12% in FVC (400 mL) and FEV1 (350 mL). In the third month after transplantation, there were additional increases, of 5% (170 mL) in FVC and 1% (50 mL) in FEV1. At the end of the first year, the functional improvement persisted, with a mean gain of 19% (620 mL) in FVC and 16% (430 mL) in FEV1.Conclusions:
Single lung transplantation in IPF patients who survive for at least one year provides significant and progressive benefits in lung function during the first year. This procedure is an important therapeutic alternative in the management of IPF. 相似文献104.
105.
A glycolytic phenotype is associated with prostate cancer progression and aggressiveness: a role for monocarboxylate transporters as metabolic targets for therapy 下载免费PDF全文
Nelma Pertega‐Gomes Sergio Felisbino Charlie E Massie Jose R Vizcaino Ricardo Coelho Chiranjeevi Sandi Susana Simoes‐Sousa Sarah Jurmeister Antonio Ramos‐Montoya Mohammad Asim Maxine Tran Elsa Oliveira Alexandre Lobo da Cunha Valdemar Maximo Fatima Baltazar David E Neal Lee GD Fryer 《The Journal of pathology》2015,236(4):517-530
Metabolic adaptation is considered an emerging hallmark of cancer, whereby cancer cells exhibit high rates of glucose consumption with consequent lactate production. To ensure rapid efflux of lactate, most cancer cells express high levels of monocarboxylate transporters (MCTs), which therefore may constitute suitable therapeutic targets. The impact of MCT inhibition, along with the clinical impact of altered cellular metabolism during prostate cancer (PCa) initiation and progression, has not been described. Using a large cohort of human prostate tissues of different grades, in silico data, in vitro and ex vivo studies, we demonstrate the metabolic heterogeneity of PCa and its clinical relevance. We show an increased glycolytic phenotype in advanced stages of PCa and its correlation with poor prognosis. Finally, we present evidence supporting MCTs as suitable targets in PCa, affecting not only cancer cell proliferation and survival but also the expression of a number of hypoxia‐inducible factor target genes associated with poor prognosis. Herein, we suggest that patients with highly glycolytic tumours have poorer outcome, supporting the notion of targeting glycolytic tumour cells in prostate cancer through the use of MCT inhibitors. © 2015 Authors. Journal of Pathology published by John Wiley & Sons Ltd on behalf of Pathological Society of Great Britain and Ireland. 相似文献
106.
Knopik VS Sparrow EP Madden PA Bucholz KK Hudziak JJ Reich W Slutske WS Grant JD McLaughlin TL Todorov A Todd RD Heath AC 《Psychological medicine》2005,35(5):625-635
BACKGROUND: Genetic influences have been shown to play a major role in determining the risk of attention-deficit hyperactivity disorder (ADHD). In addition, prenatal exposure to nicotine and/or alcohol has also been suggested to increase risk of the disorder. Little attention, however, has been directed to investigating the roles of genetic transmission and prenatal exposure simultaneously. METHOD: Diagnostic telephone interview data from parents of Missouri adolescent female twin pairs born during 1975-1985 were analyzed. Logistic regression models were fitted to interview data from a total of 1936 twin pairs (1091 MZ and 845 DZ pairs) to determine the relative contributions of parental smoking and drinking behavior (both during and outside of pregnancy) as risk factors for DSM-IV ADHD. Structural equation models were fitted to determine the extent of residual genetic and environmental influences on ADHD risk while controlling for effects of prenatal and parental predictors on risk. RESULTS: ADHD was more likely to be diagnosed in girls whose mothers or fathers were alcohol dependent, whose mothers reported heavy alcohol use during pregnancy, and in those with low birth weight. Controlling for other risk factors, risk was not significantly increased in those whose mothers smoked during pregnancy. After allowing for effects of prenatal and childhood predictors, 86% of the residual variance in ADHD risk was attributable to genetic effects and 14% to non-shared environmental influences. CONCLUSIONS: Prenatal and parental risk factors may not be important mediators of influences on risk with much of the association between these variables and ADHD appearing to be indirect. 相似文献
107.
Cross-talk between Schwann cells and neuroblasts influences the biology of neuroblastoma xenografts 下载免费PDF全文
Liu S Tian Y Chlenski A Yang Q Zage P Salwen HR Crawford SE Cohn SL 《The American journal of pathology》2005,166(3):891-900
Neuroblastoma (NB) tumors with abundant schwannian stroma have a differentiated phenotype, low vascularity, and are associated with a favorable prognosis. These observations suggest that cross-talk between Schwann cells and neuroblasts may influence tumor biology. To test this hypothesis, we developed a novel NB xenograft model with infiltrating mouse Schwann cells. Human SMS-KCNR NB cells were injected intrafascicularly (sciatic nerve-engrafted NB, n = 19) or outside the sciatic nerve (control, n = 12). Xenografts were harvested 4 to 12 weeks after tumor cell inoculation for histological studies. Schwann cells were immunostained with S-100 and species-specific p75(NGFR), major histocompatibility complex, and human leukocyte antigen antibodies. The number of proliferating cells, infiltrating Schwann cells, apoptotic cells, differentiated neuroblasts, and blood vessels in the sciatic nerve-engrafted NB tumors were compared to controls. Significantly more Schwann cells were detected in the sciatic nerve-engrafted NB xenografts than controls (P < 0.001). The infiltrating Schwann cells were S-100-positive and reacted with anti-mouse major histocompatibility complex class Ib and p75(NGFR) but not anti-human p75(NGFR) and human leukocyte antigen class I antibodies. The sciatic nerve-engrafted tumors also had lower numbers of proliferating neuroblasts, higher numbers of differentiated neuroblasts and apoptotic cells, and decreased vascular density compared to controls. Our results indicate that infiltrating Schwann cells of mouse origin are capable of promoting human neuroblast differentiation, inducing apoptosis, and inhibiting proliferation and angiogenesis in vivo. 相似文献
108.
Colland F Jacq X Trouplin V Mougin C Groizeleau C Hamburger A Meil A Wojcik J Legrain P Gauthier JM 《Genome research》2004,14(7):1324-1332
Access to the human genome facilitates extensive functional proteomics studies. Here, we present an integrated approach combining large-scale protein interaction mapping, exploration of the interaction network, and cellular functional assays performed on newly identified proteins involved in a human signaling pathway. As a proof of principle, we studied the Smad signaling system, which is regulated by members of the transforming growth factor beta (TGFbeta) superfamily. We used two-hybrid screening to map Smad signaling protein-protein interactions and to establish a network of 755 interactions, involving 591 proteins, 179 of which were poorly or not annotated. The exploration of such complex interaction databases is improved by the use of PIMRider, a dedicated navigation tool accessible through the Web. The biological meaning of this network is illustrated by the presence of 18 known Smad-associated proteins. Functional assays performed in mammalian cells including siRNA knock-down experiments identified eight novel proteins involved in Smad signaling, thus validating this integrated functional proteomics approach. 相似文献
109.
Clarice de Carvalho Veloso Marina Chaves de Oliveira Cristina da Costa Oliveira Vanessa Gregório Rodrigues Alexandre Giusti-Paiva Mauro Martins Teixeira Igor Dimitri Duarte Adaliene Versiani Matos Ferreira Andrea de Castro Perez 《Journal of ethnopharmacology》2014
Ethnopharmacological relevance
Pyrostegia venusta is used in traditional Brazilian medicine as a general tonic to treat any inflammatory disease. Several studies have demonstrated that medicinal plants constitute a therapeutic approach for the treatment of obesity-related metabolic and inflammatory disarrangement. Accordingly, we investigated the effects of hydroethanolic extract of Pyrostegia venusta flowers (PvHE) supplementation for the treatment of inflammatory and metabolic dysfunction induced by high-refined-carbohydrate (HC) diet.Material and methods
The BALB/c mice were fed chow or HC diet for 8 weeks. Part of these animals was fed with HC diet supplemented with PvHE on the 9th week until the 12th week. At the end of the dietary intervention, animals were sacrificed.Results
We observed that PvHE decreased adiposity and adipocyte area; improved glucose intolerance; reduced serum triacylglycerol levels and systemic inflammatory cells; and also reduced some inflammatory mediators levels in adipose tissue and liver.Conclusion
The results showed that PvHE has beneficial effects and may treat inflammatory and metabolic dysfunction induced by HC diet, that are associated to a negative modulation of the inflammatory process at systemic and local levels. 相似文献110.
The BRONCH‐AHF study: effects on short‐term outcome of nebulized bronchodilators in emergency department patients diagnosed with acute heart failure 下载免费PDF全文