The steroid-5-alpha-reductase, alpha polypeptide 2 (SRD5A2) gene plays a crucial role in androgen metabolism pathway in human prostate. It encodes SRD5A2 enzyme, which catalyses testosterone to dihydrotestosterone (DHT). DHT is the main active structure binding with androgen receptor (AR). After the activation of AR, it further regulates a series of target genes in androgen metabolism pathway. However, no clear consensus has been reached on the association between the SRD5A2 V89L, A49T and TA repeat polymorphisms and prostate cancer (PCa) risk. Thus, we performed a meta-analysis of 31 association studies with 14,726 PCa cases and 15,802 controls. We found no association between PCa and 89L compared with 89V allele [odds ratio (OR) = 1.02, 95% confidence interval (CI) 0.98-1.06, P(heterogeneity) = 0.44]. The 49T allele showed a significantly elevated effect on the high stage (Stages III-IV) of PCa risk both under the dominant genetic model (OR = 2.13, 95% CI 1.44-3.15, P(heterogeneity) = 0.65) and in the contrast T versus A allele (OR = 2.06, 95% CI 1.41-3.02, P(heterogeneity) = 0.69). There was a significantly decreased association between PCa and long TA repeat as compared versus short TA repeat (OR = 0.86, 95% CI 0.74-1.00, P(heterogeneity) = 0.79). No significant between-study heterogeneity was found in all subjects under four genetic models (dominant model, recessive model, allele comparison and homozygosity comparison) for these three polymorphisms, respectively, so the fixed effects model was used to pool the result. Our result indicated that carriers of 49T might improve the risk of PCa in higher stages (Stages III-IV), carriers of long TA repeat might decrease the risk of PCa and 89L may not be an important risk factor for PCa. However, due to the limited sample sizes, this meta-analysis did not achieve sufficiently conclusive results. Still more well-designed studies should be performed to clarify the role of these three polymorphisms in the development of PCa.

No abstract

Background: In recent years, disasters occurred frequently all over the world, and the role of nurses in public health emergencies and disaster emergencies was highlighted under the background of the covid19 epidemic. However, there was a lack of education and evaluation. Our study aims to cross-cultural adapt the Nurses' Perceptions of Disaster Core Competencies Scale (NPDCC) and evaluate the reliability and validity of the Chinese version.Methods: We translated the scale following the translation-integration-back translation-expert review procedure, adapted according to Chinese culture. We evaluated the reliability and validity of the scale, and a total sample of 911 nurse data from the Yangtze River Delta Regional Nursing Alliance Hospital was gathered.Results: The Chinese version of NPDCC included 45 items, 5 factors (critical thinking skills, special diagnostic skills, general diagnostic skills, technical skills, and communication skills) were extracted from the analysis, which could explain the 68.289% of the total variance. The content validity index was 0.925. The Cronbach's α of the total NPDCC score was 0.978, and 0.884-0.945 for every factor. The split-half for the scale was 0.930, and every factor was 0.861-0.894. Conclusions:The Chinese version of NPDCC has excellent reliability and validity, and it is suitable to measure nurses' perceptions of disaster core competencies in China. The next step is to promote the application in a large scale.