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31.
32.
Molecular Biology Reports - RUNX1T1 is extensively studied in the context of AML1-RUNX1T1 fusion protein in acute myeloid leukemia. Little is known about the function of RUNX1T1 itself, although...  相似文献   
33.
IntroductionCurrent serological surveillance markers to monitor colorectal cancer (CRC) or colorectal advanced adenomas (CAA) are hampered by poor sensitivity and specificity. The aim of this study is to identify and validate a panel of plasma microRNAs which change in expression after resection of such lesions.MethodsA prospectively maintained colorectal surgery database was queried for patients in whom both pre- and post-procedural serum samples had been obtained. An initial screening analysis of CRC and CAA patients (5 each) was conducted using screening cards for 380 miRNAs. Four identified miRNAs were combined with a previously described panel of 7 miRNAs that were diagnostically predictive of CRC and CAA. Differential miRNA expression was assessed using quantitative real-time polymerase chain reaction(qRT-PCR).ResultsFifty patients were included (n = 27 CRC, n = 23 CAA). There was no difference in age, gender, or race profile of CRC patients compared to CAA patients. Six miRNA were significantly increased after CRC resection (miR-324, let7b, miR-454, miR-374a, miR-122, miR-19b, all p<0.05), while three miRNAs were significantly increased following CAA resection (miR-454, miR-374a, miR-122, all p<0.05). Three miRNA were increased in common for both (miR-454, miR-374a, miR-122).DiscussionThe expression of miRNAs associated with neoplasia (either CRC or CAA) was significantly increased following surgical resection or endoscopic removal of CRC or CAA. Future studies should focus on the evaluation of these miRNAs in CRC and CAA prognosis.  相似文献   
34.
The present study demonstrates that manganese superoxide dismutase (MnSOD) (Escherichia coli), binds nitric oxide (NO) and stimulates its decay under both anaerobic and aerobic conditions. The results indicate that previously observed MnSOD-catalyzed NO disproportionation (dismutation) into nitrosonium (NO+) and nitroxyl (NO? ) species under anaerobic conditions is also operative in the presence of molecular oxygen. Upon sustained aerobic exposure to NO, MnSOD-derived NO? species initiate the formation of peroxynitrite (ONOO? ) leading to enzyme tyrosine nitration, oxidation and (partial) inactivation. The results suggest that both ONOO? decomposition and ONOO? -dependent tyrosine residue nitration and oxidation are enhanced by metal centre-mediated catalysis. We show that the generation of ONOO? is accompanied by the formation of substantial amounts of H2O2. MnSOD is a critical mitochondrial antioxidant enzyme, which has been found to undergo tyrosine nitration and inactivation in various pathologies associated with the overproduction of NO. The results of the present study can account for the molecular specificity of MnSOD nitration in vivo. The interaction of NO with MnSOD may represent a novel mechanism by which MnSOD protects the cell from deleterious effects associated with overproduction of NO.  相似文献   
35.
Abstract

Synthesis of the novel nucleoside analogues containing exocyclic pyrrolo moiety and acyclic side chains attached to the purine ring at N-9 and N-7 is described. The site of alkylation was determined by 1H and 13C NMR on the basis of chemical shifts, C-H coupling constants and connectivity in NOESY and HETCOR spectra. The N-9 substitution of 7 was proved by its X-ray crystallographic analysis.

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36.
There is increasing evidence that ATP acts on purinergic receptors and mediates synaptic transmission in the retina. In a previous study, we raised the possibility that P2X-purinoceptors, presumably P2X2-purinoceptors in OFF-cholinergic amacrine cells, play a key role in the formation of OFF pathway-specific modulation. In this study, we examined whether the P2Y1-purinoceptors can function in cholinergic amacrine cells in the mouse retina since cholinergic amacrine cells in the rat retina express P2Y1-purinoceptors. P2Y1-purinoceptors were shown to be expressed in dendrites of both ON- and OFF-cholinergic amacrine cells in adults. At postnatal day 7, there was immunoreactivity for P2Y1-purinoceptors in the soma of cholinergic amacrine cells. At postnatal day 14, weak immunoreactivity for P2Y1-purinoceptors was detected in the dendrites but not in the soma of cholinergic amacrine cells. At postnatal day 21, strong immunoreactivity for P2Y1-purinoceptors was detected in dendrites of cholinergic amacrine cells. The expression pattern of P2Y1-purinoceptors was not affected by visual experience. We concluded that P2Y1-purinoceptors are not involved in the OFF-pathway-specific signal transmission in cholinergic amacrine cells of the mouse retina.  相似文献   
37.

Introduction

Research in India has extensively examined the factors associated with non-adherence to antiretroviral therapy (ART) with limited focus on examining the relationship between adherence to ART regimen and survival status of HIV infected patients. This study examines the effect of optimal adherence to ART on survival status of HIV infected patients attending ART centers in Jharkhand, India.

Materials and Methods

Data from a cohort of 239 HIV infected individuals who were initiated ART in 2007 were compiled from medical records retrospectively for 36 months. Socio-demographic characteristics, CD4 T cell count, presence of opportunistic infections at the time of ART initiation and ART regimen intake and survival status was collected periodically. Optimal adherence was assessed using pill count methods; patients who took <95% of the specified regimens were identified as non-adherent. Cox-proportional hazard model was used to determine the relative hazards of mortality.

Results

More than three-fourths of the patients were male, on an average 34 year old and median CD4 T cell count was 118 cells/cmm at the time of ART registration. About 57% of the patients registered for ART were found to be adherent to ART. A total of 104 patients died in 358.5 patient-years of observation resulting in a mortality rate of 29 per 100 patient-years (95% confidence interval (CI): 23.9–35.2) and median survival time of 6.5 months (CI: 2.7–10.9). The mortality rate was higher among patients who were non-adherent to ART (64.5, CI: 50.5–82.4) than who were adherent (15.4, CI: 11.3–21.0). The risk of mortality was fourfold higher among individuals who were non-adherent to ART than who were adherent (Adjusted hazard ratio: 3.9, CI: 2.6–6.0).

Conclusion

Adherence to ART is associated with a higher chance of survival of HIV infected patients, ascertaining the need for interventions to improve the ART adherence and early initiation of ART.  相似文献   
38.
Obesity is a chronic inflammatory disease that weakens macrophage innate immune response to infections. Since M1 polarization is crucial during acute infectious diseases, we hypothesized that diet-induced obesity inhibits M1 polarization of macrophages in the response to bacterial infections. Bone marrow macrophages (BMMΦ) from lean and obese mice were exposed to live Porphyromonas gingivalis (P. gingivalis) for three incubation times (1 h, 4 h and 24 h). Flow cytometry analysis revealed that the M1 polarization was inhibited after P. gingivalis exposure in BMMΦ from obese mice when compared with BMMΦ from lean counterparts. Using a computational approach in conjunction with microarray data, we identified switching genes that may differentially control the behavior of response pathways in macrophages from lean and obese mice. The two most prominent switching genes were thrombospondin 1 and arginase 1. Protein expression levels of both genes were higher in obese BMMΦ than in lean BMMΦ after exposure to P. gingivalis. Inhibition of either thrombospondin 1 or arginase 1 by specific inhibitors recovered the M1 polarization of BMMΦ from obese mice after P. gingivalis exposure. These data indicate that thrombospondin 1 and arginase 1 are important bacterial response genes, whose regulation is altered in macrophages from obese mice.  相似文献   
39.
Over the past decades the role of nitric oxide (NO) and reactive oxygen species (ROS) in signaling and cellular responses to stress has witnessed an exponential trend line. Despite advances in the subject, our knowledge of the role of NO and ROS as regulators of stress and plant growth and their implication in signaling pathways is still partial. The crosstalk between NO and ROS during root formation offers new domains to be explored, as it regulates several plant functions. Previous findings indicate that plants utilize these signaling molecules for regulating physiological responses and development. Depending upon cellular concentration, NO either can stimulate or impede root system architecture (RSA) by modulating enzymes through post-translational modifications. Similarly, the ROS signaling molecule network, in association with other hormonal signaling pathways, control the RSA. The spatial regulation of ROS controls cell growth and ROS determine primary root and act in concert with NO to promote lateral root primordia. NO and ROS are two central messenger molecules which act differentially to upregulate or downregulate the expression of genes pertaining to auxin synthesis and to the configuration of root architecture. The investigation concerning the contribution of donors and inhibitors of NO and ROS can further aid in deciphering their role in root development. With this background, this review provides comprehensive details about the effect and function of NO and ROS in the development of RSA.  相似文献   
40.
Abstract

Antifungal activity-guided assay of solvent extracts of Decalepis hamiltonii (Wight & Arn) (Asclepiadaceae) against important phytopathogenic fungi, known to cause diseases in sorghum, maize and paddy proved to be highly significant. Among the five solvent extracts tested, Petroleum ether extract showed highly significant antifungal activity. Phytochemical analysis revealed that the antifungal active principle is a phenolic compound. TLC separation of the phenolic fraction using chloroform as an eluting solvent revealed the presence of seven bands but the antifungal activity was observed only in band five with Rf value 0.77. The antifungal active compound is identified as 2-hydroxy-4-methoxybenzaldehyde based on Nuclear Magnetic Resonance (NMR) and mass spectral analysis. The Minimal inhibitory concentration (MIC) varied between 200 μg ml?1 and 700 μg ml?1 depending on the fungal species. Seed treatment of the active principle significantly increased seed germination and seed vigour with a corresponding decrease in seed mycoflora. The antifungal active compound was effective against all the 24 fungal species tested suggesting broad-spectrum antifungal activity. Comparative evaluation of the active principle with the synthetic fungicides revealed that the antifungal activity of the active principle obtained from the plant is better than that of synthetic fungicide. This plant being an edible one can be exploited in the management of seed-borne pathogenic fungi and the prevention of biodeterioration of grains and mycotoxin elaboration during storage.  相似文献   
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