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1.
Metabolic Brain Disease - Multiple neuronal injury pathways are activated during cerebral ischemia and reperfusion (I/R). This study was designed to decrease potential neuronal injuries by using...  相似文献   
2.

Background

Various investigations have reported that the internal mammary artery (IMA) is an efficient and functional choice of conduit for vascular graft surgeries, especially for coronary artery bypass grafts; however, the quest to find an ideal vascular substitute remains. We hypothesized that acellular IMA could be an appropriate graft for small-diameter vascular bypasses that could be used in various surgeries including coronary artery bypass grafting.

Methods

We decellularized human IMAs and performed histologic evaluations and scanning electron microscopy to confirm the decellularization process and the preservation of the extracellular matrix. Subsequently, we grafted the scaffolds into the superficial femoral arteries of 8 New Zealand rabbits with an end-to-end anastomosis. Computed tomography angiograms were provided at 3, 12, and 36 months postoperatively. Subsequently, the animals were killed, and biopsies were taken for histologic and immunohistochemical assessments.

Results

Evaluation of the acellular tissue confirmed the efficacy of the decellularization protocol and the preservation of the extracellular matrix. All 8 animals survived the entire follow-up period. Doppler ultrasonography and computed tomography angiographies verified the conduit's patency. Histologic assessments depicted the recellularization of all 3 layers of the scaffold. Smooth muscle cells were detected in tunica media. Immunohistochemical assessments confirmed these findings.

Conclusions

In conclusion, we demonstrated that acellular human IMA could be used as an efficient small-diameter vascular substitute with high patency. These findings could pave the path for future investigations on the clinical application of acellular IMA as a novel vascular graft for small-diameter bypass surgeries.  相似文献   
3.
Proceedings of the National Academy of Sciences, India Section B: Biological Sciences - Regenerative medicine has been increased for helping crucial diseases and injuries. Planarians have appeared...  相似文献   
4.

Research question

Previous studies of aromatase inhibitors on male infertility have focused on men with low testosterone–oestradiol ratio of less than 10. Can aromatase inhibitors improve spermatogenesis in men with idiopathic male infertility with normal testosterone–oestradiol ratio?

Design

Prospective study of men with idiopathic severe oligozoospermia (sperm concentration <5 million/ml) carried out between February 2015 and March 2017. The objective was to assess if semen-analysis parameters improved after treatment with letrozole. Secondary objectives were to monitor the safety of letrozole in men, and to measure the alterations in serum FSH, LH, oestradiol and testosterone levels.

Results

Fifteen men with normal testosterone–oestradiol ratio (>10) were treated with letrozole 2.5 mg daily for 4 months. This produced a 5.5-fold increase in sperm concentration (P?=?0.0068). All men had increased total serum testosterone and suppressed oestradiol levels after treatment, thus raising the overall testosterone–oestradiol ratio (P < 0.0001). Adverse effects from letrozole were relatively minor and included loss of libido (54%), headaches (25%), fatigue (21%), weakness (13%), loss of hair (8%) and dry mouth (8%).

Conclusions

Letrozole improves sperm concentration and increases testosterone–oestradiol ratio for men with oligozoospermia who have normal testosterone–oestradiol ratio; its role in the treatment of male infertility may be extended to this group of patients. In addition, it is a relatively well-tolerated drug with no serious adverse effects.  相似文献   
5.
Objective: Due to the increasing annual incidence rate of disability and mortality in patients with acute myocardial infarction (AMI), the need for an appropriate diagnostic tool has become a crucial urgent issue. An increase in biomarkers and protein levels in response to AMI can be used as a predictive biomarker with different sensitivities and specificities. This study aimed at investigating the role of miR-19a as a biomarker with acceptable sensitivity and specificity for early diagnosis of AMI. Methods: We studied 175 patients with AMI admitted within 12 h of symptom onset and 90 healthy subjects as control group. Patients were divided into two groups, including group I (normal vessels and no significant artery stenosis) and primary percutaneous coronary intervention (PCI) group II (patients with more than 50% stenosis in vessels and severe atherosclerosis) diagnosed by angiography. The expression level of miR-19a was evaluated by the real-time polymerase chain reaction and other serum chemistries were also analyzed. Results: The results demonstrated that circulating miR-19a levels were significantly increased in patient groups compared to the control group (2.88 ± 1.06 vs. 5.93 ± 1.28, P<0.0001). We also found that miR-19a levels were higher in group II (134.62-fold) than group I (15.42-fold). The upper levels of miR-19a were significantly correlated with the increased serum levels of CK-MB (ρ=0.29, P<0.0001), CTn I (ρ=0.4, P<0.0001) and creatinine (ρ=0.27, P<0.0001). In addition, Receiver Operating Characteristic (ROC) analysis revealed that circulating miR-19a had considerable diagnostic accuracy for the patients with normal vessel with an AUC of 0.930 (95% CI: 0.697-0.765) and for PCI patients with an AUC of 0.966 (95% CI: 0.748-0.784). Conclusion: Circulating miR-19a possibly has prognostic value to be used as a promising molecular target for early diagnosis and prognosis of AMI.  相似文献   
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AimsThe rising prevalence of metabolic syndrome has made it a major health concern. Chronic occupational exposure to organic solvents affects different systems of the body. This study aimed to investigate the association between exposure to organic solvents and the prevalence of metabolic syndrome in petroleum refinery workers.MethodThis study was conducted in 2019–2020 on workers employed in an Iranian petroleum refinery. The demographic and occupational information on the participants was obtained using the interview method. Their height, weight, and blood pressure were measured by the occupational health team, and fasting blood samples were taken from them to measure the paraclinical parameters.ResultsIn this study, 1009 petroleum refinery workers were analyzed. The prevalence of metabolic syndrome in workers was 20.1% and it was about two times higher in exposed workers (CI 95%: 1.61–3.35) compared to non-exposed ones. Factors associated with the prevalence of metabolic syndrome include age, higher BMI, exercise, and longer exposure to organic solvents.ConclusionFindings of this study suggested that exposure to organic solvents is associated with increased prevalence of metabolic syndrome (the highest association was observed with elevated serum triglycerides). Besides, longer exposure to organic solvents increased the risk of developing metabolic syndrome.  相似文献   
8.
Chronic pelvic pain syndrome (CPPS) can be triggered by a various types of gynecological, gastrointestinal, urological, and musculoskeletal disorders. Recently, the role of the central nervous system has proven to be an integral part on the development of any chronic pain syndrome, including CPPS. However, owing to the complex and heterogeneous etiology and pathophysiology of CPPS, the establishment of effective therapeutic interventions remains challenging for both physicians and patients. Nonetheless, recent studies have pointed that medicinal plants and their secondary metabolites can be effectively used in CPPS therapy, besides contributing to restore the patients' quality of life and potentiate the conventional CPPS management. In this sense, this review aims to provide a careful overview on the biomedical data for the use of medicinal plants use and their secondary metabolites on CPPS management.  相似文献   
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