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A novel series of N′‐(2‐(3,5‐disubstituted‐4H‐1,2,4‐triazol‐4‐yl)acetyl)‐6/7/8‐substituted‐2‐oxo‐2H‐chromen‐3‐carbohydrazides were synthesized and studied for their α‐glucosidase inhibition activity. Most of the synthesized compounds exhibited potential α‐glucosidase inhibition activity with IC50 values ranging from 0.96 ± 0.02 to 32.86 ± 0.73 µg/ml. Among them, compounds 3e and 4e , having a methoxy group on the coumarin ring, proved to be the most potent ones, showing an enzyme inhibition activity with IC50 = 0.96 ± 0.02 and 1.44 ± 0.06 µg/ml, respectively. The kinetic study through Lineweaver–Burk plots revealed that the inhibition mechanism of the most active compounds 3d, 3e, 4d , and 4e , on the α‐glucosidase activity, was found to be in the competitive mode.  相似文献   
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Iron overload increases the risk of infections, veno-occlusive disease and hepatic dysfunction in post-transplant period. Our objective was to investigate the association of pre-transplant ferritin levels with complications and survival after allogeneic hematopoietic stem cell transplantation (alloHSCT).We retrospectively analysed 84 patients' data who had undergone allogeneic HSCT into two groups: patients with a serum ferritin level ≥ 1000 ng/ml, and patients with <1000 ng/ml at the time of HSCT.Cox-regression analysis showed that pre-transplant serum ferritin levels were significantly higher in patients who had at least one infectious event compared with those who had no any infectious event in the post-transplant 100 days (p<0.023). Overall survival (OS) and disease-free survival (DFS) rates were significantly higher in patients with a time-to-tx interval 12 months (p=0.002 and p=0.008 respectively). A higher risk of death was observed in high-ferritin group (hazard ratio=2.27, CI:1.01-5.09, p=0.023 for OS and hazard ratio=2.49, CI:1.12-5.53 p=0.039 for DFS). No significant effect on OS and DFS among groups was observed for variables conditioning regimen, gender and diagnosis. Acute GVHD was more common in patients with a ferritin level ≥ 1000 ng /mL, but this was not statistically significant (p>0.05). There was no statistical significance in both groups (ferritin ≥ 1000 ng /mL and ferritin <1000 ng/mL) for relapse rates (p>0.05). Platelet and neutrophil engaftment day was not found statistically significant compared with both groups (p=0.273 and p=0.882, respectively). Pre-transplant ferritin levels may predict poor outcomes in patients who had undergone allogeneic hematopoietic stem cell transplantation.  相似文献   
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BackgroundAnemia is highly prevalent in inflammatory bowel disease patients, and red blood cell transfusion is often indicated already at reproductive age. Both transfusion and pregnancy may induce red cell alloantibodies, potentially complicating further transfusions and pregnancies. As recent evidence suggests that inflammation may promote red cell antibody induction, the alloimmunization risk of these patients after allogenic erythrocyte exposure was investigated.MethodsRed cell alloantibody status and clinical data were analyzed in 193 inflammatory bowel disease patients with a history of transfusion or pregnancy, and compared with transfused controls with noninflammatory diseases (n = 357).ResultsIn transfused patients with inflammatory bowel disease, a 2.5-fold-increased red cell antibody prevalence was found (10/119, 8.4%), compared with transfused sex-matched controls with noninflammatory diseases (12/357, 3.4%; P = .023). Patients with inflammatory bowel disease had fewer transfusions (mean 3.0 vs 4.2, P = .003) but higher C-reactive protein levels during transfusion than controls (mean 8.4 vs 5.4 mg/dL, P <.001). The red cell antibodies of inflammatory bowel disease patients were clinically significant, directed against different Rh, Kell, Duffy, or Lutheran blood group antigens, and associated with higher number of transfusions (odds ratio 1.57; 95% confidence interval, 1.03-2.39). Conversely, immunomodulatory therapy during transfusion showed negative association (odds ratio 0.12; 95% confidence interval, 0.02-0.61). Only 1.4% of inflammatory bowel disease patients with pregnancy alone had antibodies.ConclusionsPatients with inflammatory bowel disease exhibited a very high risk of transfusion-induced red cell alloimmunization, possibly potentiated by inflammation. Aside from a restrictive transfusion strategy, the implementation of prophylactic blood group phenotype matching of red cell concentrates (not only for ABO and RhD but also RhCcEe, Kell, Kidd, Duffy) could prevent antibody induction and associated complications in these patients.  相似文献   
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Objectives

Grape seed proanthocyanidin extract (GSPE) is a potent antioxidant and a free radical scavenger. This study was designed to determine whether GSPE could protect against dysfunction and oxidative stress induced by torsion–detorsion injury in rat testis.

Methods

A total of 45 male Wistar albino rats were divided into five groups: control group, sham group, torsion–detorsion (T/D) group, T/D + GSPE group, GSPE group. GSPE was administrated 100 mg/kg/day with oral gavage over seven days before torsion. Testicular torsion was performed for 2 h, and afterward, detorsion was performed for 2 h. The rats were decapitated under ketamine anesthesia, and their testes tissues were removed. Tissue malondialdehyde, advanced oxidation protein products levels, eNOS expression, apoptosis and histopathological damage scores were then compared.

Results

Testicular torsion–detorsion caused significant increases in malondialdehyde level, apoptosis and eNOS expression level and caused a significant decrease in advanced oxidation protein product levels and testicular spermatogenesis in ipsilateral testes. GSPE prevented the rise in malondialdehyde, apoptosis and eNOS expression and improved testicular morphology and Johnsen’s score.

Conclusions

As a result, testicular torsion gives rise to serious damage in testes and GSPE is a potent antioxidant agent in preventing testicular injury.  相似文献   
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This study investigated the effects of rutin against reproductive damage caused by toxic mercury in male rats. Thirty-five Sprague Dawley rats were used. Control group was injected with saline for 7 days. The rutin-100 group received 100 mg/kg/b.w. rutin for 7 days. Mercuric chloride (HgCl2) group received 1.23 mg/kg/b.w. of HgCl2 for 7 days. Mercury chloride + rutin-50 group received 50 mg/kg/b.w. rutin and HgCl2 1.23 mg/kg/b.w. for 7 days. HgCl2 + rutin-100 group received 100 mg/kg/b.w. rutin and HgCl2 1.23 mg/kg/b.w. for 7 days. It was detected that HgCl2 treatment increased malondialdehyde (MDA) levels, tumour necrosis factor-α (TNF-α) and cyclooxygenase-2 (COX-2) expressions, necrosis and degeneration of spermatogonium, dead and abnormal sperm percentages; tubular walls thinning; and decreased antioxidant enzyme activities and sperm motility. It was determined that rutin application reduced testicular damage caused by HgCl2. In conclusion, rutin administration may treat HgCl2 toxicity in testes.  相似文献   
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