Prevalence and genotype distribution of human papillomavirus infections in women attending hospitals in Chaozhou of Guangdong province.

BACKGROUND: Human papillomavirus (HPV) infection is the main cause of cervical cancer. Limited epidemiologic data of HPV prevalence are available for women attending hospitals in southern China. This study aimed to evaluate the profiles of HPV infection and cytology status in gynecological outpatients in Chaozhou City. METHODS: A total of 2833 eligible women were enrolled. The HPV GenoArray test was used for HPV detection and genotyping. Nearly one half of the HPV positive women received liquid-based cytology test. Logistic regression analysis was performed to assess the predictable effects of age and genotype for categories of abnormal cytology. RESULTS: The prevalence of overall, high-risk, and low-risk HPV infection were 24.5%, 19.5% and 8.4%, respectively. A U-shaped age-specific prevalence curve was observed in overall HPV and high- risk HPV, but not in low-risk HPV, which declined with age increasing. The 6 most common high-risk HPV type in descending order, were types 52, 16, 58, 18, 68, and 33. Age and HPV genotype were both important determinants of abnormal cytology incidence, the older women (>45 years) and those infected with HPV type 16 and/or 18 having the highest risk for abnormal cytology. CONCLUSION: Our findings support the hypothesis that second-generation HPV prophylactic vaccines including HPV-52 and -58 may offer higher protection for women residing in Chaozhou and neighboring cities in Guangdong.

Evaluation of the genetic variability of human papillomavirus type 52.

Human papillomavirus (HPV) type 52 is one of the high-risk HPV types. Its variants can be classified as of Asian and European lineages, while little data of HPV 52 variants are available from China. In this study, the complete E6 and L1 genes were amplified and sequenced in 79 samples from eastern Guangdong, China. In total, 21 variants were identified, 18 of which could be divided into Asian lineage and the other three were phylogenetically related to European lineage. No significant difference was found between the pathogenicity of these two lineage variants. Two HPV-52 lineages variants could be classified by high resolution melting (HRM) analysis. Thus, we believe that the application of HRM analysis would be useful for facilitating pathogenic comparisons between different HPV variants. In addition, we found that 6 females were infected with two types of HPV-52 variants. To our knowledge, this is the first time that this rare phenomenon is reported worldwide.

A study of circulating gliadin antibodies in schizophrenia among a Chinese population.

The present work measured circulating antibodies against native gliadins, deamidated gliadin-derived epitopes, and transglutaminase 2 (TGM2) in 473 patients with schizophrenia and 478 control subjects among a Chinese population. The results showed that 27.1% of patients with schizophrenia were positive for the IgA antibody against native gliadins compared with 17.8% of control subjects (χ(2) = 11.52, P = .0007, OR = 1.72, 95% CI 1.25-2.35), although this significant difference appeared to be due mainly to low IgA gliadin antibody levels in female controls. A total of 27.6% of female patients were positive for IgA gliadin antibodies compared with 13.9% of female controls (χ(2) = 10.46, P = .0012, OR = 2.36, 95% CI 1.39-4.01), and 26.4% of male patients were positive for IgA antibodies compared with 19.8% of male controls (χ(2) = 3.26, P = .071, OR = 1.46, 95% CI 0.97-2.19). Of 128 patients who were positive for the IgA antibody against native gliadins, 8 were positive for the IgA antibody against deamidated gliadin epitopes and 1 was positive for IgA anti-TGM2 antibody. However, quantitative analysis demonstrated that the mean levels of IgA antibodies against deamidated gliadin epitopes and TGM2 were significantly lower in patients with schizophrenia than the control subjects (P < .001 and P = .008, respectively). The prevalence of IgG antibodies against native gliadins was not significantly different between the patient group and the control group (χ(2) = 2.25, P = .134, OR = 1.32, 95% CI 0.92-1.88). This study suggests that specific gliadin-derived epitopes may be involved in schizophrenia.

Genetic and functional study of the IPO5 gene in schizophrenia.

The present work reported on a weak association of the importin 5 (IPO5) gene with schizophrenia in combined family and case-control samples and also investigated a possible mechanism by which the IPO5 gene may contribute to the development of the disease in a Chinese population. Our results suggest that abnormal expression and alternative splicing of the IPO5 gene may be involved in the pathophysiology of schizophrenia.

Is KPNB3 locus associated with schizophrenia?

OBJECTIVE: To reconfirm the association of KPNB3 with schizophrenia in Chinese population. METHODS: Two single nucleotide polymorphisms (SNPs), rs2588014 and rs626716 at the KPNB3 locus, were genotyped in 304 Chinese Han family trios consisting of fathers, mothers, and affected offsprings with schizophrenia. These 2 SNPs were detected by PCR-based restriction fragment length polymorphism (RFLP) analysis. The Hardy-Weinberg equilibrium for genotypic distributions was estimated by the goodness-of-fit test. The UNPHASED program was used to perform transmission disequilibrium test (TDT), haplotype analysis, and pair-wise measure of linkage disequilibrium (LD) between these 2 SNPs. RESULTS: The genotypic distributions of both rs2588014 and rs626716 were in the Hardy-Weinberg equilibrium (P > 0.05). The TDT revealed allelic association with rs626716 (chi2 = 9.31, P = 0.0023) but not with rs2588014 (chi2 = 3.44, P = 0.064). The global P-value was 0.0099 for 100 permutations. The haplotype analysis also showed a disease association (chi2 = 25.97, df = 3, P = 0.0000097). CONCLUSION: The present study provides further evidence in support of the KPNB3 association with schizophrenia in Chinese population.

Effect of X-rays on expression of caspase-3 and p53 in EL-4 cells and its biological implications.

OBJECTIVE: To investigate the effect of X-rays on expression of caspase-3 and p53 protein in EL-4 cells and its implications in induction of apoptosis and polyploid cells. METHODS: Mouse lymphoma cell line (EL-4 cells) was used. Fluorescent staining and flow cytometry analysis were employed for measurement of protein expression, apoptosis, cell cycle, and polyploid cells. RESULTS: The expression of caspase-3 protein increased significantly at 8 h and 12 h, compared with that of sham-irradiated control (P<0.05, respectively) and the expression of p53 protein increased significantly at 2, 4, 8, 12, and 24 h, compared with that of sham-irradiated control (P<0.05-P<0.01) in EL-4 cells after 4.0 Gy X-irradiation. Apoptosis of EL-4 cells was increased significantly at 2, 4, 8, 12, 24, 48, and 72 h after 4.0 Gy exposure, compared with that of sham-irradiated control (P<0.05-P<0.001). G2 phase cells were increased significantly at 4, 8, 12, 24, 48, and 72 h (P<0.05-P<0.001). However, no marked change in the number of 8 C polyploid cells was found from 2 to 48 h after 4.0 Gy exposure. CONCLUSION: The expressions of caspase-3 and p53 protein in EL-4 cells are induced by X-rays, which might play an important role in the induction of apoptosis, and the molecular pathway for polyploid formation might be p53-independent.

Searching for a schizophrenia susceptibility gene in the 22q11 region.

OBJECTIVE: To investigate a genetic association for schizophrenia within chromosome 22q11 in a Chinese Han population. METHODS: The PCR-based restriction fragment length polymorphism (PCR-RFLP) analysis was used to detect three single nucleotide polymorphisms (SNPs), rs165655 (A/G base change) and rs165815 (C/T base change) present in the ARVCF (armadillo repeat gene deletion in velocardiofacial syndrome) locus, and rs756656 (A/C base change) in the LOC128979 (expressed sequence tags, EST) locus, among 100 Chinese family trios consisting of fathers, mothers and affected offspring with schizophrenia. Genotype data were analyzed by using linkage disequilibrium (LD) methods including haplotype relative risk (HRR) analysis, transmission disequilibrium test (TDT) and haplotype transmission analysis. RESULTS: The genotype frequency distributions of three SNPs were all in Hardy-Weinberg equilibrium (P>0.05). Both the HRR and the TDT analysis showed that rs165815 was associated with schizophrenia (chi2=6.447, df=1, P=0.011 and chi2=6.313, df=1, P=0.012, respectively), whereas the other two SNPs did not show any allelic association. The haplotype transmission analysis showed a biased transmission for the rs165655-rs165815 haplotype system (chi2=17.224, df=3, P=0.0006) and for the rs756656-rs165655-rs165815 hapoltype system (chi2=20.965, df=7, P=0.0038). CONCLUSION: Either the ARVCF gene itself or a nearby locus may confer susceptibility to schizophrenia in a Chinese Han population.

[Searching for a schizophrenia susceptibility gene in the 22q11 region].

OBJECTIVE: To investigate the genetic association for schizophrenia within the long arm region 1 band 1 of chromosome 22 (22q11) in a Han Chinese population. METHODS: Polymerase chain reaction (PCR)-based restriction fragment length polymorphism (RFLP) analysis was used to detect three single nucleotide polymorphism (SNPs), rs165655 (A/G base change) and rs165815 (C/T base change) present in the ARVCF (armadillo repeat gene deletion in velocardiofacial syndrome) locus, and rs756656 (A/C base change) in the LOC128979 (expressed sequence tags, EST) locus, among 100 nuclear families composed of fathers, mothers and affected offspring with schizophrenia. Genotyping data were analyzed by linkage disequilibrium methods including haplotype relative risk (HRR) analysis, transmission disequilibrium test (TDT) and haplotype transmission analysis. RESULTS: The genotype frequency distributions of three SNPs were all in Hardy-Weinberg equilibrium; Both HRR and TDT analysis showed that rs165815 was associated with schizophrenia (P < 0.05), whereas the other two SNPs did not show any allelic association. The haplotype transmission analysis showed a biased transmission for the rs165655-rs165815 haplotype system and for the rs756656-rs165655-rs165815 haplotype system (P < 0.01). CONCLUSION: Either ARVCF gene itself or a nearby locus might confer susceptibility to schizophrenia in a Han Chinese population.

Is NOTCH4 associated with schizophrenia?

The NOTCH4 locus was reported to be associated with schizophrenia in our previous study but the subsequent replication by other workers has been inconsistent. To find out possible reasons for the poor replication, the present work was undertaken to analyse four functional single nucleotide polymorphisms (SNPs) (rs367398, rs915894, rs520692 and rs422951) at the NOTCH4 locus among 141 schizophrenic family trios of Chinese Han descent. Of these four SNPs, rs520692 was the only one associated with schizophrenia (P = 0.017); the other three, however, did not show any association with the illness, including rs367398 located in the promoter region, which had shown a strong association with the illness in our previous study conducted with British samples. Although these four SNPs analysed lie within a less than 4 kb segment of genomic DNA, the pattern of linkage disequilibrium between them was unexpected. The strongest linkage disequilibrium was shown only between rs367398 and rs520692 and between rs520692 and rs422951 in both parent and patient groups. This study raises the possibility that there might be two or more disease-underlying variants at the NOTCH4 locus or at a nearby locus, and that the allelic or locus heterogeneity may be one of the possible reasons for the poor replication of the NOTCH4 finding.

Lack of a genetic association between the TNXB locus and schizophrenia in a Chinese population.

A recent study demonstrated that the tenascin X (TNXB) gene was associated with schizophrenia in a British population. To replicate the initial finding, we analysed two positive single nucleotide polymorphisms (SNPs), rs1009382 and rs204887 present at the TNXB locus, in a Chinese population by using PCR-based restriction fragment length polymorphism analysis. We recruited a total of 136 family trios consisting of fathers, mothers and affected offspring with schizophrenia. The transmission disequilibrium test did not show allelic association between these two SNPs and schizophrenia, and the rs1009382-rs204887 haplotypes were not associated with the illness either. The present results suggest that the TNXB locus does not appear to be associated with schizophrenia in the Chinese population. Because the TNXB gene is less than 100 kb away from the NOTCH4 locus that was also reported to be associated with schizophrenia, allelic and locus heterogeneity could be possible reasons for the failure to replicate the TNXB finding.

Effect of ionizing radiation on the expression of p16, cyclinD1 and CDK4 in mouse thymocytes and splenocytes.

OBJECTIVE: To investigate the effect of ionizing radiation on the expression of p16, CyclinD1, and CDK4 in mouse thymocytes and splenocytes. METHODS: Fluorescent staining and flow cytometry analysis were employed for the measurement of protein expression. RESULTS: In time course experiments, it was found that the expression of p16 protein was significantly increased at 8, 24, and 48 h for thymocytes (P < 0.05, P < 0.01, and P < 0.05, respectively) and at 24 h for splenocytes (P < 0.05) after whole body irradiation (WBI) with 2.0 Gy X-rays. However, the expression of CDK4 protein was significantly decreased from 8 h to 24 h for thymocytes (P < 0.05-P < 0.01) and from 8 h to 72 h for splenocytes (P < 0.05-P < 0.01). In dose effect experiments, it was found that the expression of p16 protein in thymocytes and splenocytes was significantly increased at 24 h after WBI with 1.0, 2.0, and 4.0 Gy (P < 0.05-P < 0.01), whereas the expression of CDK4 protein was significantly decreased with 2.0 Gy for thymocytes (P < 0.05) and 0.5-6.0 Gy for splenocytes (P < 0.05-P < 0.01). Results also showed that the expression of CyclinD1 protein decreased markedly in both thymocytes and splenocytes after exposure. CONCLUSION: The results indicate that the expression of p16 protein in thymocytes and splenocytes can be induced by ionizing radiation, and the p16-CyclinD1/CDK4 pathway may play an important role for G1 arrest of thymocytes induced by X-rays.