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21.
Background: The prompt identification of patients with poor prognosis is essential in order to improve the treatment outcomes in prostate cancer (CaP); as a novel approach, several molecular markers, including integrins, have been discussed as prognostic biomarkers. Our aim was to comprehensively examine aberrant expression of integrins in correlation with clinicopathological features and prognosis in CaP by synthesizing all available evidence, in a systematic review and meta-analysis. Methods: A systematic review and meta-analysis was performed in accordance with the Preferred Reporting Items for Systematic Review and Meta-analysis (PRISMA) guidelines. Scientific literature databases (Pubmed, Embase, and Scopus) were systematically searched until May 10, 2020. Random-effects (DerSimonian-Laird) models were used to estimate pooled odds ratios (ORs) for cross-sectional correlations with clinicopathological characteristics and relative risks for longitudinal associations with prognosis. Results: Fourteen studies were included with a total number of 3,194 CaP cases examined (13 cross-sectional and four longitudinal cohort study arms). Correlation of low expression of α6 (pooled OR = 0.10, 95% confidence interval [CI]: 0.04–0.28, P < 0.001) and β1 (pooled OR = 0.45; 95% CI: 0.21–1.00, P = 0.049) integrin with high Gleason score was noted. A borderline trend between reduced expression of α6 integrin and an advanced clinical stage of CaP (pooled OR = 0.48; 95% CI: 0.22-1.03, P = 0.06) was observed. No associations with biochemical recurrence and survival were documented. Conclusions: Evidence on the association of low expression of integrins α6 and β1 and more advanced CaP exist, whereas significant results on survival were not documented; further studies are warranted.  相似文献   
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Erectile dysfunction affects a large segment of the male population, and in most cases impaired relaxation of the smooth muscle cells in the corpus cavernosum and the penile arteries is a factor. Sildenafil, a relatively specific vasodilator of the penile circulation, has revolutionized the treatment of impotence. This article describes the biochemistry of erection, outlines the problems that can lead to erectile dysfunction and explains how sildenafil acts to relieve these problems at the cellular and molecular level. Other aspects of therapy, such as potential side effects and absolute and relative contraindications, are also discussed.  相似文献   
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Growing evidence suggests that sleep could affect the immunological response after vaccination. The aim of this prospective study was to investigate possible associations between regular sleep disruption and immunity response after vaccination against coronavirus disease 2019 (COVID-19). In total, 592 healthcare workers, with no previous history of COVID-19, from eight major Greek hospitals were enrolled in this study. All subjects underwent two Pfizer–BioNTech messenger ribonucleic acid (mRNA) COVID-19 vaccine BNT162b2 inoculations with an interval of 21 days between the doses. Furthermore, a questionnaire was completed 2 days after each vaccination and clinical characteristics, demographics, sleep duration, and habits were recorded. Blood samples were collected and anti-spike immunoglobulin G antibodies were measured at 20 ± 1 days after the first dose and 21 ± 2 days after the second dose. A total of 544 subjects (30% males), with median (interquartile range [IQR]) age of 46 (38–54) years and body mass index of 24·84 (22.6–28.51) kg/m2 were eligible for the study. The median (IQR) habitual duration of sleep was 6 (6–7) h/night. In all, 283 participants (52%) had a short daytime nap. In 214 (39.3%) participants the Pittsburgh Sleep Quality Index score was >5, with a higher percentage in women (74·3%, p < 0.05). Antibody levels were associated with age (r = −0.178, p < 0.001), poor sleep quality (r = −0.094, p < 0.05), insomnia (r = −0.098, p < 0.05), and nap frequency per week (r = −0.098, p < 0.05), but after adjusting for confounders, only insomnia, gender, and age were independent determinants of antibody levels. It is important to emphasise that insomnia is associated with lower antibody levels against COVID-19 after vaccination.  相似文献   
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OBJECTIVES: This study was conducted (1) to examine whether the GSTM1 and GSTT1 null genotypes are risk factors for bladder cancer, and (2) to study a possible association of these genotypes with disease severity. METHODS: This case-control study was undertaken over a 21-month period and included 89 newly diagnosed transitional cell bladder cancer patients and 147 controls; both patients and controls originated from a defined population (residents of the loannina region, Northwestern Greece) and were similar with regard to mean age, male to female ratio and smoking habits. The GSTM1 and GSTT1 genotypes were identified by multiplex polymerase chain reaction on peripheral blood DNA samples. Genotype frequencies among patients and controls were assessed and the association of the genotypes with tumor grade and stage at presentation were statistically evaluated by the chi(2) test. RESULTS: The GSTM1 null genotype was strongly associated with bladder cancer. The odds ratio, attributable and population attributable risks were estimated at 2.76, 0.64 and 0.40, respectively. The correlation between the GSTM1 null genotype with stage, although not statistically significant, was estimated at an odds ratio of 2.6 for invasive disease. The correlation of GSTM1 null genotype with tumor grade did not yield a statistically significant result. The GSTT1 null genotype was not statistically associated with bladder cancer. CONCLUSION: According to our study, individuals with the GSTM1 null genotype carry a substantially higher risk for bladder carcinogenesis. The GSTM1 null genotype is not associated with more aggressive disease in terms of tumor grade, although there is a correlation between this genotype and stage of the disease.  相似文献   
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BACKGROUND: Engineering a graft to secrete its own immunosuppressive antibodies may minimize the risks associated with current high dose systemic immunosuppression. METHODS AND RESULTS: A beta cell insulinoma cell line (NIT-1) was transfected with genes encoding a chimeric anti-CD4 antibody. The NIT-1 cells secreted functional chimeric anti-CD4 antibody that bound to the CD4 molecule on mouse thymocytes and inhibited in vitro proliferation of CD4+ve T cells. Both test and control transfected cell lines grew at a similar rate in immunodeficient mice. In immunocompetent NOD mice, NIT-1 cells are normally rejected by a cellular immune response against the SV40 T antigen. Although control transfected NIT-1 cells were rapidly rejected by NOD mice, anti-CD4 secreting NIT-1 cells grew significantly better and were able to form tumors at the site of injection. CONCLUSIONS: The local secretion of chimeric anti-CD4 antibody from transfected cells can contribute to graft survival in our transplantation model.  相似文献   
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T-cell-derived antigen-binding molecules (TABMs) specific for benzoic acid were isolated from the serum of a toluene-sensitive patient. The resulting purified TABMs (BA-TABMs) did not contain immunoglobulin G and were associated with the cytokine transforming growth factor-β (TGF-β). BA-TABMs bound to benzoic acid conjugated to human serum albumin (BA-HSA), as well as to other chemicals conjugated to human serum albumin—including dinitrophenol and oxazolone. The binding of BA-TABMs to the conjugated chemicals increased the level of detectable TGF-β, and a similar effect was observed with the unconjugated chemicals, benzoic acid and 2,4-dinitrophenol glycine. The increase in TGF-β was critically dependent on the ratio between BA-TABMs and the conjugated or unconjugated chemicals; the increase was optimum at intermediate concentrations and absent at low and high concentrations. The authors used an established animal model in vivo and demonstrated that TGF-β enhanced the inflammatory response induced by the release of neuropeptides from sensory nerves; this enhancement occurred in a dose-dependent manner. The BA-TABMs also enhanced this neurogenic inflammatory response in a dose-dependent manner, and this effect was blocked by anti-TGF-β antibody. When the authors added either BA-HSA or benzoic acid, the effect of BA-TABMs on neurogenic inflammation was further enhanced at intermediate concentrations of antigen and was unaltered or reduced at higher concentrations. TABMs specific to particular chemicals, as a result of their association with cytokines (e.g., TGF-β), may be implicated in symptom production in chemically sensitive patients.  相似文献   
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We illustrate the intravascular ultrasound (US) findings in the evaluation of left gonadal vein anatomic variations. During a 2‐year period, 4 consecutive patients (mean age, 37 years; range, 28–45 years) with left‐sided varicocele underwent embolization. Intravascular US examinations and retrograde venography were performed to assess varicocele anatomy. Anatomic variants were recorded and categorized. A comparison between intravascular US and fluoroscopic findings was performed. The Fisher exact test was used for statistical analysis (P < .05). Technical success was achieved in all cases. There was a statistically significant difference in the maximum gonadal vein diameter between venography and intravascular US (P = .0087). Intravascular US showed left gonadal vein anatomic variations and better ability in the evaluation of the vein diameter.  相似文献   
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