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961.
Chagas disease (CD) is a chronic and endemic illness caused by the parasite Trypanosoma cruzi. Microvascular disturbances play an important role in the progress of the disease. The purinergic signaling system participates in regulatory functions, such as immunomodulation, neuroprotection, and thromboregulation. This study aimed to investigate the activities of purinergic system ecto-enzymes present on the platelet surface and the platelet aggregation profile from patients with indeterminate form of Chagas disease (IFCD). Thirty patients diagnosed with IFCD and 30 healthy subjects were selected. Ecto-nucleoside triphosphate diphosphohydrolase (E-NTPDase), ecto-nucleotide pyrophosphatase/phosphodiesterase (E-NPP), ecto-5′-nucleotidase (E-5′-NT) and ecto-adenosine deaminase (E-ADA) activities were measured in platelets isolated from these individuals as well as the platelet aggregation. Results demonstrated an increase of 21 % in the E-NPP activity and 30 % in the E-5′-NT activity in IFCD group (P < 0.05); however, a decrease of 34 % in the E-ADA activity was determined in the same group (P < 0.001). A significant decrease of 12.7 % and 12.8 % in the platelet aggregation of IFCD group in two different concentrations of ADP (5 and 10 μM) was observed, respectively (P < 0.05). Increased E-NPP and E-5-NT activities as well as decreased E-ADA activity in platelets of patients with IFCD contributed to decrease platelet aggregation, suggesting that the purinergic system is involved in the thromboregulation process in these patients, since adenosine (the final product of ATP hydrolysis) has cardioprotective and vasodilator effects that prevent the clinical progress of the disease.  相似文献   
962.
This review reports the occurrence of flavonoids in subtribe Centaureinae of Asteraceae family. It extensively covers the literature up to 2010 and collects all available 13C‐NMR data.  相似文献   
963.
Software advancements in the last several years have had a significant impact on proteomics from method development to data analysis. Herein, we detail a method, which uses our in-house developed software tool termed Skyline, for empirical refinement of candidate peptides from targeted proteins. The method consists of four main steps from generation of a testable hypothesis, method development, peptide refinement, to peptide validation. The ultimate goal is to identify the best performing peptide in terms of ionization efficiency, reproducibility, specificity, and chromatographic characteristics to monitor as a proxy for protein abundance. It is important to emphasize that this method allows the user to perform this refinement procedure in the sample matrix and organism of interest with the instrumentation available. Finally, the method is demonstrated in a case study to determine the best peptide to monitor the abundance of surfactant protein B in lung aspirates.  相似文献   
964.
In this study thirty-three novel indole derivatives were designed and synthesized based on the structure of deformylflustrabromine B (1), a metabolite isolated from the marine bryozoan Flustra foliacea L. The syntheses were carried out using standard methodologies and in good yields. The molecules were tested for their affinities for the α4β21, α3β41, α71 and (α1)2β1γδ nicotinic acetylcholine receptor (nAChR) subtypes. Binding assays showed that, among these ligands, compound 7c exhibited the highest affinity with Ki = 136.1, 93.9 and 862.4 nM for the α4β21, α3β41, and α71 nAChRs subtypes, respectively. These results indicated that the indole core might be a useful scaffold for the development of new potent and selective nAChR ligands.  相似文献   
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966.
967.
Protection by parenteral immunization with plasmid DNA vaccines against pulmonary tuberculosis (TB) is very modest. In this study, we have investigated the underlying mechanisms for the poor mucosal protective efficacy and the avenues and mechanisms to improve the efficacy of a single i.m. immunization with a monogenic plasmid DNA TB vaccine in a murine model. We show that i.m. DNA immunization fails to elicit accumulation of Ag-specific T cells in the airway lumen despite robust T cell responses in the spleen. Such systemically activated T cells cannot be rapidly mobilized into the airway lumen upon Mycobacterium tuberculosis exposure. However, airway deposition of low doses of soluble mycobacterial Ags in previously immunized mice effectively mobilizes the systemically activated T cells into the airway lumen. A fraction of such airway luminal T cells can persist in the airway lumen, undergo quick, robust expansion and activation and provide marked immune protection upon airway M. tuberculosis exposure. Airway mucosal deposition of soluble mycobacterial Ags was found to create a tissue microenvironment rich in proinflammatory molecules including chemokines and hence conducive to T cell recruitment. Thus, in vivo neutralization of MIP-1alpha or IFN-inducible protein-10 markedly inhibited the accumulation of Ag-specific T cells in the airway lumen. Our data suggest that immunoprotective efficacy on the mucosal surface by i.m. plasmid DNA immunization could be substantially improved by simple mucosal soluble Ag inoculation and restoration of mucosal luminal T cells. Our study holds implication for the future design of DNA vaccination strategies against intracellular infections.  相似文献   
968.
Cutas DE 《Bioethics》2008,22(1):56-63
The paper presents and briefly analyses some of the provisions of a Romanian legislative proposal which arrived at the Presidency for ratification twice, in slightly different forms, and which was rejected twice: the first time at the Presidency in October 2004, and the second at the Constitutional Court in July 2005. The proposal was finally dropped in February 2006. My intention here is to point to some of the most problematic deficiencies of the legislative document in the hope that this may assist with future debates and regulations on assisted reproduction either in Romania or elsewhere. I have isolated the features to be discussed under two headings: (1) whose are the rights to reproduce, that the document claimed to ‘acknowledge, regulate and guarantee’ and (2) what is the status of the embryo, the child and the surrogate mother?  相似文献   
969.
The hemoglobin gene 1 (dmeglob1) of the fruit fly Drosophila melanogaster is expressed in the tracheal system and fat body, and has been implicated in hypoxia resistance. Here we investigate the expression levels of dmeglob1 and lactate dehydrogenase (a positive control) in embryos, third instar larvae and adult flies under various regimes of hypoxia and hyperoxia. As expected, mRNA levels of lactate dehydrogenase increased under hypoxia. We show that expression levels of dmeglob1 are decreased under both short- and long-term hypoxia, compared with the normoxic (21% O2) control. By contrast, a hypoxia/reoxygenation regime applied to third instar larvae elevated the level of dmeglob1 mRNA. An excess of O2 (hyperoxia) also triggered an increase in dmeglob1 mRNA. The data suggest that Drosophila hemoglobin may be unlikely to function merely as a myoglobin-like O2 storage protein. Rather, dmeglob1 may protect the fly from an excess of O2, either by buffering the flux of O2 from the tracheoles to the cells or by degrading noxious reactive oxygen species.  相似文献   
970.
Galectin-4 is a carbohydrate-binding protein belonging to the galectin family. Here we provide novel evidence that galectin-4 is selectively expressed and secreted by intestinal epithelial cells and binds potently to activated peripheral and mucosal lamina propria T-cells at the CD3 epitope. The carbohydrate-dependent binding of galectin-4 at the CD3 epitope is fully functional and inhibited T cell activation, cycling and expansion. Galectin-4 induced apoptosis of activated peripheral and mucosal lamina propria T cells via calpain-, but not caspase-dependent, pathways. Providing further evidence for its important role in regulating T cell function, galectin-4 blockade by antisense oligonucleotides reduced TNF-alpha inhibitor induced T cell death. Furthermore, in T cells, galectin-4 reduced pro-inflammatory cytokine secretion including IL-17. In a model of experimental colitis, galectin-4 ameliorated mucosal inflammation, induced apoptosis of mucosal T-cells and decreased the secretion of pro-inflammatory cytokines. Our results show that galectin-4 plays a unique role in the intestine and assign a novel role of this protein in controlling intestinal inflammation by a selective induction of T cell apoptosis and cell cycle restriction. Conclusively, after defining its biological role, we propose Galectin-4 is a novel anti-inflammatory agent that could be therapeutically effective in diseases with a disturbed T cell expansion and apoptosis such as inflammatory bowel disease.  相似文献   
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