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71.
72.
There are no reliable markers useful to predict the onset or the evolution of chronic graft-versus-host disease (cGVHD) after allogeneic hematopoietic stem cell transplantation (HSCT), although several candidate biomarkers have been identified from limited hypothesis-driven studies. In this study we evaluated 14 patients who received a reduced intensity conditioning HSCT. Seven patients had cGVHD, whereas 7 never developed cGVHD during the period of observation. The expression of 114 cytokines in immunoselected cell populations was explored by microarray analysis and 11 cytokines were selected for further evaluation by real-time PCR. Differential gene expression measurements showed a significant up-regulation for INFγ (interferon, gamma) in CD8+ and for TNFSF3 (tumor necrosis factor superfamily, member 3) and for TNFSF10 (tumor necrosis factor superfamily, member 10) in CD14+ cell population when comparing cGVHD with control samples. The expression levels were significantly decreased for TNFSF10 in CD8+ cell population and for TNFSF12 (tumor necrosis factor superfamily, member 12) and for PDGFβ (platelet-derived growth factor, beta) in CD4+. Our data seem to suggest that different immune populations can play a role in cGVHD pathogenesis and the early detection of gene expression profile in these patients could be useful in the monitoring of GVHD. We hypothesized that PDGFβ down-regulation could represent a negative feedback to compensate for enhanced expression of its receptor recently reported.  相似文献   
73.
Neurochemical Research - Haloperidol is a widely used antipsychotic, despite the severe motor side effects associated with its chronic use. This study was carried out to compare oral dyskinesia...  相似文献   
74.
Increasing evidence on the importance of fluctuations in NAD+ levels in the living cell is accumulating. Therefore a deeper knowledge on the regulation of coenzyme synthesis and recycling is required. In this context the study of NMN adenylyltransferase (EC 2.7.7. 1), a key enzyme in the NAD+ biosynthetic pathway, assumes a remarkable relevance. We have previously purified to homogeneity and characterized the protein from the thermophilic archaeon Sulfolobus solfataricus. The determination of partial sequence of the S. solfataricus enzyme, together with the recent availability of the genome sequence of the archaeon Methanococcus jannaschii allowed us, based on sequence similarity, to identify the M. jannaschii NMN adenylyltransferase gene. As far as we know from literature, this is the first report on the NMN adenylyltransferase gene.  相似文献   
75.
The activity of several enzymes with different intracellular sites was determined in urine at various times following nonfatal acute tubular necrosis induced by mercuric chloride administration. The excretion rate of all tested enzymes rose on the 1st and 2nd day; in the next observations (days 7-15) enzymatic values approached the basal values. The lactate dehydrogenase isoenzyme pattern of the renal cortical zone showed an early shift towards cathodic fractions and later (7 days) an increase of middle ones; the normal anodic zymogram recovered after a suitable time interval (30 days). The isoenzymatic changes are related both to the renal hypoxia and to the appearance of less differentiated cells. The behaviour of functional parameters (urine flow, osmolality, urea clearance, creatinine clearance) were well in agreement with the observed enzyme and renal isoenzyme changes.  相似文献   
76.
Synechocystis sp. slr0787 open reading frame encodes a 339 residue polypeptide with a predicted molecular mass of 38.5 kDa. Its deduced amino acid sequence shows extensive homology with known separate sequences of proteins from the thermophilic archaeon Methanococcus jannaschii. The N-terminal domain is highly homologous to the archaeal NMN adenylyltransferase, which catalyzes NAD synthesis from NMN and ATP. The C-terminal domain shares homology with the archaeal ADP-ribose pyrophosphatase, a member of the 'Nudix' hydrolase family. The slr0787 gene has been cloned into a T7-based vector for expression in Escherichia coli cells. The recombinant protein has been purified to homogeneity and demonstrated to possess both NMN adenylyltransferase and ADP-ribose pyrophosphatase activities. Both activities have been characterized and compared to their archaeal counterparts.  相似文献   
77.
The beta-adrenoceptor antagonist propranolol is used in the therapy of hypertension and ischemic heart disease. The aim of our study was to evaluate the effects of this drug on platelet aggregation and on synthesis of thromboxane B2 (the stable metabolite of Thromboxane A2) from platelet rich plasma (PRP), whole blood samples and during spontaneous clotting. The results indicate that propranolol at concentrations near the therapeutic range, significantly inhibit collagen and thrombin-induced platelet aggregation and TxB2 synthesis from PRP. Furthermore the drug demonstrates inhibitory activity on B-TG release and TxB2 production from whole blood samples and on spontaneous clotting. The results suggest that some benefits of propranolol in the treatment of patients with coronary artery disease or cardiovascular conditions associated with platelet hyperaggregability may also be related to interference with platelet activation "in vivo" and with TxA2 generation.  相似文献   
78.
Objective Alpha hemoglobin-stabilizing protein (AHSP) inhibits the production of reactive oxygen species in various cells, including erythrocytes. Reduced AHSP can mean reduced protection from stressors. Our objective was to investigate whether AHSP is involved in the response to stress in pregnancy. Study design Placentas were collected from normal term pregnancies (n = 10) and pregnancies complicated by HELLP (n = 10), intrauterine growth restriction (IUGR; n = 10) or fetal death (IUFD; n = 6). AHSP messenger RNA (mRNA) and protein were determined using real time quantitative polymerase chain reaction (PCR) and Western blot, respectively. All statistical analyses were performed by using the GraphPad Prism Software. Differences were considered significant at p < 0.05. Results Placental AHSP mRNA level in HELLP (4.16E10−4 ± 1.77) and IUFD (4.19E10−4 ± 3.37) were significantly decreased compared with controls (28.47E10−4 ± 14.86; p < 0.01), whereas levels in the IUGR group (7.55E10−4 ± 6.4) showed a trend toward being lower but the difference did not reach statistical significance. Western blot analysis results indicate a no significant increase of ASHP protein in the HELLP syndrome group and a significant decrease in the IUFD group compared with controls. There was no significant difference between the IUGR and control groups. Conclusion ASHP mRNA expression in the placenta is decreased in complicated pregnancies, and it may be involved in the pathogenic mechanisms leading to the adverse pregnancy outcome. This paper was presented as a poster at the 27th Annual Meeting of the Society for Maternal Fetal Medicine; San Francisco, CA, USA, February 5–10, 2007. Monica Emanuelli and Davide Sartini contributed equally to this paper.  相似文献   
79.
alpha-Lipoic acid (LA) has been found previously to accelerate wound repair in patients affected by chronic wounds who underwent hyperbaric oxygen (HBO) therapy. Because proteinases are important in wound repair, we hypothesized that LA may regulate matrix metalloproteinase (MMP) expression in cells that are involved in wound repair. Patients undergoing HBO therapy were double-blind randomized into two groups: the LA group and the placebo group. Gene expression profiles for MMPs and for angiogenesis mediators were evaluated in biopsies collected at the first HBO session, at the seventh HBO session, and after 14 days of HBO treatment. ELISA tests were used to validate microarray expression of selected genes. LA supplementation in combination with HBO therapy downregulated the inflammatory cytokines and the growth factors which, in turn, affect MMPs expression. The disruption of the positive autocrine feedback loops that maintain the chronic wound state promotes progression of the healing process.  相似文献   
80.
Activated hepatic stellate cells (HSC) are the major source of collagen I in liver fibrosis. Eugenia uniflora L. is a tree species that is widely distributed in South America. E. uniflora L. fruit—popularly known as pitanga—has been shown to exert beneficial properties. Autophagy contributes to the maintenance of cellular homeostasis and survival under stress situation, but it has also been suggested to be an alternative cell death pathway. Mitochondria play a pivotal role on signaling cell death. Mitophagy of damaged mitochondria is an important cell defense mechanism against organelle-mediated cell death signaling. We previously found that purple pitanga extract induced mitochondrial dysfunction, cell cycle arrest, and death by apoptosis and necrosis in GRX cells, a well-established activated HSC line. We evaluated the effects of 72-h treatment with crescent concentrations of purple pitanga extract (5 to 100 μg/mL) on triggering autophagy in GRX cells, as this is an important mechanism to cells under cytotoxic conditions. We found that all treated cells presented an increase in the mRNA expression of autophagy-related protein 7 (ATG7). Concomitantly, flow cytometry and ultrastructural analysis of treated cells revealed an increase of autophagosomes/autolysosomes that consequentially led to an increased mitophagy. As purple pitanga extract was previously found to be broadly cytotoxic to GRX cells, we postulated that autophagy contributes to this scenario, where cell death seems to be an inevitable fate. Altogether, the effectiveness on inducing activated HSC death can make purple pitanga extract a good candidate on treating liver fibrosis.  相似文献   
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