Isolation and identification of human periodontal ligament stem cells in vitro / 华西口腔医学杂志

<p><b>OBJECTIVE</b>To isolate and identify human periodontal ligament stem cells (PDLSC) by improved methods and assess the characteristics of PDLSC ex vivo.</p><p><b>METHODS</b>The periodontal ligament cells were obtained from the healthy impacted third molars and teeth extracted for orthodontic purposes and used to isolate PDLSC by limiting dilution assay. PDLSC were cultured and expanded in alpha-MEM supplemented with 10% FBS. Colony-forming assay, immunohistochemistry, flow cytometry, osteogenic and adipogenic induction were used to identify PDLSC.</p><p><b>RESULTS</b>The obtained cells had high colony-forming efficiency and were positive staining for vimentin and negative for pancytokeratin. Flow cytometry revealed that the isolated cells were positive for STRO-1 and CD146 antibodies and most were in the G0/G1 phase of cell cycle. Under specific conditions, they could differentiate to the osteoblast and adipocyte lineages in vitro.</p><p><b>CONCLUSION</b>Limiting dilution assay is an effective method to isolate PDLSC and the single-cell-derived colonies demonstrate the properties of stem cells in vitro.</p>

Association of nicotinic acetylcholine receptor subunit alpha-4 polymorphisms with smoking behaviors in Chinese male smokers / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>It has been reported that the nicotinic acetylcholine receptor subunit α4 gene (CHRNA4) might be associated with smoking behaviors in the previous studies. Up to now, there are few reports on the relationship between CHRNA4 and smoking initiation. In this study, we tried to explore the role of two polymorphisms in CHRNA4 (rs1044396 and rs1044397) in smoking initiation and nicotine dependence in Chinese male smokers.</p><p><b>METHODS</b>Nine hundred and sixty-six Chinese male lifetime nonsmokers and smokers were assessed by the Fagerström test for nicotine dependence (FTND), smoking quantity (SQ) and the heaviness of smoking index (HSI). All subjects were divided into four groups based on their tobacco use history and the FTND scores. The polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) was performed to find two polymorphisms of CHRNA4 in these subjects.</p><p><b>RESULTS</b>The χ(2) test showed that rs1044396 was significantly associated with smoking initiation (χ(2) = 4.65, P = 0.031), while both rs1044396 and rs1044397 were significantly associated with nicotine dependence (χ(2) = 5.42, P = 0.020; χ(2) = 7.58, P = 0.005). Furthermore, the T-G (3.9%) haplotype of rs1044396-rs1044397 showed significant association with smoking initiation (χ(2) = 6.30, P = 0.012) and the C-G haplotype (58.9%) remained positive association with nicotine dependence (χ(2) = 8.64, P = 0.003) after Bonferroni correction. The C-G haplotype also significantly increased the HSI (P = 0.002) and FTND scores (P = 0.001) after Bonferroni correction.</p><p><b>CONCLUSION</b>These findings suggest that CHRNA4 may be associated with smoking initiation and the C-G haplotype of rs1044396-rs1044397 might increase the vulnerability to nicotine dependence in Chinese male smokers.</p>

Application of the Children' s Impact of Event Scale (Chinese Version) on a rapid assessment of posttraumatic stress disorder among children from the Wenchuan earthquake area / 中华流行病学杂志

Objective To explore the reliability and validity of the Children' s Impact of Event Scale (Chinese version, CRIES-13) and to determine the value and the optimal cutoff point of the score of CRIES-13 in screening posttraumatic stress disorder(PTSD), so as to provide evidence for PTSD prevention and identify children at risk in Wenchuan earthquake areas. Methods A total of 253 children experienced the Wenchuan earthquake were tested through Stratified random cluster sampling. The authors examined CRIES-13's internal consistency, discriminative validity and predictive value of the cut-off. PTSD was assessed with the DSM-Ⅳ criteria. Area under the curve while sensitivity, specificity and Youden index were computed based on the receiver operating characteristic curve analysis. Optimal cutoff point was determined by the maximum of Youden index. Results 20.9% of the subjects were found to have met the DSM-Ⅳ criteria for PTSD 7 months after the Wenchuan earthquake accident. The Cronbach' s coefficient of CRIES-13 was 0.903 and the mean inter-item correlation coefficients ranged from 0.283 to 0.689, the correlation coefficient of the three factors with the total scale scores ranged from 0.836 to 0.868 while the correlation coefficient among the three factors ranged from 0.568 to 0.718, PTSD cases indicated much higher scores than non-PTSD cases, the Youden index reached maximum value when the total score approached 18 in CRIES-13 with sensitivity and specificity as 81.1% and 76.5% respectively. Consistency check showed that there were no significant differences between the results of CRIES-13 score ≥32 and clinical diagnosis (Kappa=0.529) from the screening program. Conclusion CRIES-13 appeared to be a reliable and valid measure for assessing the posttraumatic stress symptoms among children after the earthquake accident in the Wenchuan area. The CRIES-13 seemed to be a useful self-rating diagnostic instrument for survivors with PTSD symptoms as a clinical concern by using a 18 cut-off in total score. Consistency check showed that there was no significant difference between the screening result of CRIES- 13 score ≥ 32 and clinical diagnosis.

Advances in the studies of the dysbindin gene in schizophrenia / 中华医学遗传学杂志

Recent reports indicate that the dysbindin gene located on chromosome 6p22.3 is a major susceptibility gene for schizophrenia. In the brain, the dysbindin gene may influence glutamatergic neurotransmission by multiple post- and pr- synaptic mechanisms. This paper reviews the research progress on the dysbindin gene in schizophrenia, including the dysbindin gene and its product, the possible pathogenic mechanisms, the association study of the dysbindin gene with schizophrenia, and the cognitive decline caused by the dysbind in variations.