Association of vitamin D receptor gene variants with polycystic ovary syndrome: a meta-analysis.

BACKGROUND: Polycystic ovary syndrome (PCOS) is a common endocrine disorder in reproductive-age women. Multiple susceptible gene as well as environmental factors and their interaction each other are contributed to the PCOS risk. Several case-control studies have researched the associations of the vitamin D receptor gene (VDR) polymorphisms with PCOS susceptibility, but the jury is still out. Here, we carried out a meta-analysis to clarify polymorphisms between ApaI (C/A) (rs7975232), BsmI (G/A) (rs1544410), FokI (C/T) (rs10735810), TaqI (T/C) (rs731236) and Tru9I (G/A) (rs757343) in the VDR gene and PCOS susceptibility based on relative lager sample size. METHODS: English database of PubMed and Embase, and Chinese database of Wanfang and China National Knowledge Infrastructure (CNKI) databases were retrivaled for the relationship between VDR gene variates and PCOS susceptibility published before 31th, May 2018. Crude odds ratios (ORs) and its 95% confidence intervals (95% CIs) in different comparisons were used to detected the strength of the association. All the statistical analyses of the present meta-analysis were performed by STATA version 12.0 software. RESULTS: Totally, 3587 (PCOS group 1922; control group 1665) participants from 13 studies were included which met our inclusion criteria. A statistically significant association between VDR ApaI (rs7975232) polymorphism and PCOS susceptibility (C vs. A: OR = 1.19, 95%CI = 1.06~1.34, P = 0.004) was found in the overall population. After stratified by ethnicity, we showed that there is a significant association between VDR ApaI (rs7975232) polymorphism and susceptibility to PCOS in the Asian (C vs. A: OR = 1.21, 95%CI = 1.04~1.42, P = 0.016) population, but this association was not found in the Caucasian population. Additionally, a significant relationship between VDR BsmI (rs1544410) variates with PCOS susceptibility in the Asian (G vs. A: OR = 1.27, 95%CI = 1.06~1.53, P = 0.011) population, but this association was not found in the Caucasian population. We didn't find any association between VDR FokI (rs2228570), VDR TaqI (rs731236), VDR Tru9I (rs757343) and PCOS susceptibility in the overall and the subgroup populations. CONCLUSIONS: Our findings demonstrated that VDR ApaI (rs7975232) and VDR BsmI (rs1544410) polymorphisms are correlated with susceptibility to PCOS in the Asian population and VDR TaqI (rs731236), VDR FokI (rs2228570), VDR Tru9I (rs757343) did not reveal a relationship with the PCOS susceptibility.

Repair of segmental long bone defect in a rabbit radius nonunion model: comparison of cylindrical porous titanium and hydroxyapatite scaffolds.

A segmental long bone defect in a rabbit radius nonunion model was repaired using cylindrical porous titanium (Ti) and hydroxyapatite (HA) scaffolds. Each scaffold was produced using the same method, namely, a slurry foaming method. Repairing ability was characterized using x-radiographic score 12 and 24 weeks postprocedure; failure load of the radius-ulna construct, under three-point bending, 12 weeks postprocedure; and the percentage of newly formed bone within the implant, 12 and 24 weeks after postprocedure. For each of these parameters, the difference in the results when porous Ti scaffold was used compared with when HA scaffolds were used was not significant; both porous scaffolds showed excellent repairing ability. Because the trabecular bone is a porous tissue, the interconnected porous scaffolds have the advantages of natural bone, and vasculature can grow into the porous structure to accelerate the osteoconduction and osteointegration between the implant and bone. The porous Ti scaffold not only enhanced the bone repair process, similar to porous HA scaffolds, but also has superior biomechanical properties. The present results suggest that porous Ti scaffolds may have promise for use in the clinical setting.