Single nucleotide polymorphisms of HER2 related to osteosarcoma susceptibility.

AIMS: The purpose of this study was to investigate the correlation between single necleotide polymorphisms (SNPs) of human epidermal growth factor receptor-2 (HER2) gene with osteosarcoma susceptibility in Chinese Han population. METHODS: 90 patients with osteosarcoma and 100 healthy controls who were frequency-matched with the former by age and gender were enrolled for a case-control study. 5 SNPs of HER2, namely rs2952155, rs1810132, rs2952156, rs1136201 and rs1058808, were tested by Sequenom time of flight mass spectrometry technique. The linkage disequilibrium and haplotype were analyzed using haploview software. The risk intensity of osteosarcoma was expressed by odds ratio (OR) with 95% confidence interval (CI) which was calculated by chi-squared text. Hardy-Weinberg equilibrium (HWE) was also evaluated by chi-squared text. RESULTS: HER2 gene rs1136201 and rs1058808 polymorphisms were associated with the increased risk of osteosarcoma (P=0.04 and 0.02, respectively). Allele G in rs1136201 was 1.67 higher risk for osteosarcoma in cases than the control group (OR=1.67, 95% CI=1.11-2.51) and G allele of rs1058808 polymorphism also significantly increased osteosarcoma susceptibility (OR=2.06, 95% CI=1.27-3.22). The haplotype analysis showed that haplotype C-T-G-G might be a susceptible haplotype to osteosarcoma (OR=1.74, 95% CI=1.01-3.00). HWE test was eligible in controls (P>0.05). CONCLUSION: HER2 gene rs1136201 and rs1058808 polymorphisms and haplotype C-T-G-G may be related to osteosarcoma susceptibility in Chinese Han population, indicating that the interaction of gene polrmorphism plays an role in osteosarcoma risk.

Genetic variations in the KIR gene family may contribute to susceptibility to ankylosing spondylitis: a meta-analysis.

The present meta-analysis of relevant case-control studies was conducted to investigate the possible relationships between genetic variations in the killer cell immunoglobulin-like receptor (KIR) gene clusters of the human KIR gene family and susceptibility to ankylosing spondylitis (AS). The following electronic databases were searched for relevant articles without language restrictions: the Web of Science, the Cochrane Library Database, PubMed, EMBASE, CINAHL, the Chinese Biomedical Database (CBM) and Chinese National Knowledge Infrastructure (CNKI) databases, covering all papers published until 2013. STATA statistical software was adopted in this meta-analysis as well. We also calculated the crude odds ratios (OR) and its 95% confidence intervals (95 % CI). Seven case-control studies with 1,004 patients diagnosed with AS and 2,138 healthy cases were implicated in our meta-analysis, and 15 genes in the KIR gene family were also evaluated. The results of our meta-analysis show statistical significance between the genetic variations in the KIR2DL1, KIR2DS4, KIR2DS5 and KIR3DS1 genes and an increased susceptibility to AS (KIR2DL1: OR 7.82, 95% CI 3.87-15.81, P< 0.001; KIR2DS4: OR 1.91, 95% CI 1.16-3.13, P = 0.010; KIR2DS5: OR1.51, 95% CI 1.14-2.01, P = 0.004; KIR3DS1: OR 1.58, 95% CI 1.34-1.86, P< 0.001; respectively). However, we failed to found positive correlations between other genes and susceptibility to AS (all P >0.05). The current meta-analysis provides reliable evidence that genetic variations in the KIR gene family may contribute to susceptibility to AS, especially for the KIR2DL1, KIR2DS4, KIR2DS5 and KIR3DS1 genes.

[Comparison of stability of sacroiliac screws in the treatment of bilateral sacral fractures in a finite element model].

OBJECTIVE: To compare the stability of sacroiliac screws fixation for the treatment of bilateral vertical sacral fractures to provide reference for clinic application. METHODS: A finite element model of Tile C pelvic ring injury (bilateral type Denis II fracture of sacrum) was produced. The bilateral sacral fractures were fixed with sacroiliac screws in 4 types of models respectively: two bidirectional sacroiliac screws fixation in the S1 segment, two bidirectional sacroiliac screws fixation in the S2 segment, one sacroiliac screw fixation in the S1 segment and one sacroiliac screw fixation in the S2 segment, two bidirectional sacroiliac screws fixation in S1 and S2 segments respectively. By the ABAQUS 6.9.1 software, in the case of standing on both feet, 600 N vertical load was imitated to be imposed to the superior surface of the sacrum and downward translation and backward angle displacement of the middle part of the sacral superior surface and everted angle displacement of the top of iliac bones were extracted for analysis. The stability of sacroiliac screws fixation was compared according to the principle of the better stability the smaller displacement. RESULTS: The stability of 2 bidirectional sacroiliac screws fixation in S1 and S2 segments respectively was markedly superior to that of 2 bidirectional sacroiliac screws fixation in S1 or S2 segment and was also markedly superior to that of one sacroiliac screw fixation in S1 segment and one sacroiliac screw fixation in S2 segment. The vertical and everted stability (the downward translation: 0.531 mm; the everted angle displacement: 0.156° (left side), 0.163° (right side)) of sacroiliac screws fixation in two bidirectional sacroiliac screws fixation in the S2 segment was superior to that of two bidirectional sacroiliac screws fixation in the S1 segment (the downward translation: 0.673 mm; the everted angle displacement: 0.200° (left side), 0.232° (right side)). The rotational stability of two bidirectional sacroiliac screws fixation in the S1 segment (the backward angle displacement: 0.269°) was superior to that of two bidirectional sacroiliac screws fixation in the S2 segment (the backward angle displacement: 0.287°). Moreover, the rotational stability of one sacroiliac screw fixation in the S1 segment and one sacroiliac screw fixation in the S2 segment was inferior to that of two bidirectional sacroiliac screws fixation in the S1 segment or two bidirectional sacroiliac screws fixation in the S2 segment, and the vertical and everted stability of one sacroiliac screw fixation in the S1 segment and one sacroiliac screw fixation in the S2 segment was between that of two bidirectional sacroiliac screws fixation in the S1 segment and two bidirectional sacroiliac screws fixation in the S2 segment. CONCLUSIONS: Two bidirectional sacroiliac screws fixation in S1 and S2 segments respectively is recommended to be utilized for fixing bilateral sacral fractures of Tile C pelvic ring injury as far as possible. It is suggested to choose sacral segments in which sacroiliac screws fixed according to vertical, rotational and everted stability degree of sacral fractures.

[Repairing segmental radial bone defect with poly (3-hydroxybutyrate-co-3-hydroxyvalerate)/sol-gel bioactive glass composite porous scaffold].

OBJECTIVE: To investigate the capability of the bone regeneration of poly (3-hydroxybutyrate-co-3-hydroxyvalerate/sol-gel bioactive glass (PHBV/SGBG) composite porous scaffold. METHODS: PHBV/ SGBG composite porous scaffold was implanted into the segmental radial bone defect of the New Zealand white rabbits, PHBV/hydroxylapatite (PHBV/HA) as experimental control. The degradability, biocompatibility, and bone regeneration capability of the implants were evaluated through radiological, histological, computerized graphic, and biomechanical analysis. RESULTS: The new bone formation occurred as early as 4 weeks after implantation of PHBV/SGBG composite porous scaffold. The defect was filled with new bone 8 weeks after the implantation, and was completely repaired 12 weeks after operation. The new bone had normal bone structure and the medullar cavity regenerated. The biomechanical study showed that the anti-compression force of radial specimen in PHBV/SGBG groups was significantly higher than in PHBV/ HA groups (P < 0.05), but no significant difference existed between PHBV/SGBG group and autograft bone group (P>0.05). The PHBV/SGBG composite porous scaffold degraded no sooner than 4 weeks after the implantation and most of scaffold was absorbed after 12 weeks. The proportion of the scaffold to new bone decreased from 60% by week 4 to 8% by week 12. CONCLUSIONS: PHBV/SGBG composite porous scaffold is a degradable bone substitute. It can achieve early bone generation and complete repair. It can be used as an ideal scaffold for tissue-engineering bone.