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Chen W.,Southern Medical University | Chen W.,Jinan University | Zhang X.,303 Hospital of Peoples Liberation Army of China | Shang X.,Southern Medical University | And 6 more authors.
BMC Medical Genetics | Year: 2010

Background: The clinical syndrome of thalassemia intermedia (TI) results from the β-globin genotypes in combination with factors to produce fetal haemoglobin (HbF) and/or co-inheritance of α-thalassemia. However, very little is currently known of the molecular basis of Chinese TI patients.Methods: We systematically analyzed and characterized β-globin genotypes, α-thalassemia determinants, and known primary genetic modifiers linked to the production of HbF and the aggravation of α/β imbalance in 117 Chinese TI patients. Genotype-phenotype correlations were analyzed based on retrospective clinical observations.Results: A total of 117 TI patients were divided into two major groups, namely heterozygous β-thalassemia (n = 20) in which 14 were characterized as having a mild TI with the Hb levels of 68-95 g/L except for five co-inherited αααanti-3.7triplication and one carried a dominant mutation; and β-thalassemia homozygotes or compound heterozygotes for β-thalassemia and other β-globin defects in which the β+-thalassemia mutation was the most common (49/97), hemoglobin E (HbE) variants was second (27/97), and deletional hereditary persistence of fetal hemoglobin (HPFH) or δβ-thalassemia was third (11/97). Two novel mutations, Term CD+32(A→C) and Cap+39(C→T), have been detected.Conclusions: Chinese TI patients showed considerable heterogeneity, both phenotypically and genotypically. The clinical outcomes of our TI patients were mostly explained by the genotypes linked to the β- and α-globin gene cluster. However, for a group of 14 patients (13 β0/βNand 1 β+/βN) with known heterozygous mutations of β-thalassemia and three with homozygous β-thalassemia (β0/β0), the existence of other causative genetic determinants is remaining to be molecularly defined. © 2010 Chen et al; licensee BioMed Central Ltd. Source

Ye X.,Guangdong Pharmaceutical University | Ye X.,Southern Medical University | Fu J.,Liuzhou Municipal Maternity and Child Healthcare Hospital | Yang Y.,Southern Medical University | And 3 more authors.
PLoS ONE | Year: 2013

Background:Although previous meta-analyses have suggested an association between aspirin use and risk of gastric cancer, current evidence is inconsistent. Additionally, it remains unclear whether there are frequency-risk and duration-risk relationships and if a threshold of effect exists.Methods:We identified studies by searching MEDLINE and PUBMED databases and reviewing relevant articles. We derived the summary risk estimates using fixed-effects or random-effects model based on homogeneity analysis. The dose-response meta-analysis was performed by linear trend regression and restricted cubic spline regression. Potential heterogeneity was tested using the Q statistic and quantified with the I2 statistic. Subgroup analyses and Galbraith plots were used to explore the potential sources of heterogeneity. Publication bias was evaluated with funnel plots and quantified by the Begg's and Egger's test.Results:Fifteen studies were included in this meta-analysis. There was an overall 29% reduced risk of gastric cancer corresponding to aspirin use (RR = 0.71, 95% CI 0.60-0.82). We found there are nonlinear frequency-risk and linear duration-risk relations between aspirin use and gastric cancer. A monotonically decreasing relation was observed only for low-frequency (≤4.5 times/week) aspirin intake (10% decreased risk for once/week, 19% for twice/week and 29% for 4.5 times/week), and the frequency threshold of aspirin use is 4.5 times per week. Regarding those with duration of aspirin use, there was a tendency towards stronger risk reduction of gastric cancer for longer aspirin use (10% decreased risk for 4 years, 19% for 8 years and 28% for 12 years), and no duration threshold was observed.Conclusion:Our findings suggest that long-term (≥4 years) and low-frequency (1-4.5 times per week) aspirin use is associated with a statistically significant, dose-dependent reduction in the risk of gastric cancer. © 2013 Ye et al. Source

Jia X.-Y.,Capital Medical University | Jia X.-Y.,Peking Union Medical College | Wei X.-J.,Capital Medical University | Wei X.-J.,Shanxi Medical University | And 7 more authors.
Chinese Journal of Medical Genetics | Year: 2011

Objective: To establish a comprehensive and simple assay using denaturing high performance liquid chromatography (DHPLC) for the diagnosis of most common mutations and deletions of α-thalassemia gene in Southeast Asians and Southern Chinese. Methods: This assay has included a duplex polymerase chain reaction (PCR) followed by DHPLC analysis. An improved PCR was also performed followed by DHPLC analysis. With this assay, a blinded study of 160 samples was screened for three common mutations and three common deletions. Results: The duplex PCR-DHPLC combined with the improved PCR-DHPLC analysis has detected all mutations and the wild-type allele. The results were consistent with those by the original methods. Conclusion: This molecular assay may be used for the diagnosis of α-thalassemia patients from this geographical region. The method is accurate, rapid, semi-automatic and cost-effective, which makes it suitable for large-scale screening. Source

Xiong F.,Southern Medical University | Huang Q.,Xiamen University | Chen X.,Xiamen University | Zhang X.,303 Hospital of Peoples Liberation Army | And 12 more authors.
Journal of Molecular Diagnostics | Year: 2011

The increasing number of disease-causing mutations demands a simple, direct, and cost-effective diagnostic genotyping technique capable of detecting multiple mutations. This study validated the efficacy of a novel melting curve analysis-based genotyping assay (MeltPro HBB assay) for 24 β-thalassemia mutations in the Chinese population. The diagnostic potential of this assay was evaluated in 1022 pretyped genomic DNA samples, including 909 clinical cases of β-thalassemia minor or major, using a double-blind analysis in a multicenter validation study. Reproducibility of the assay was 100%, and the limit of detection was 10 pg per reaction. All 24 β-thalassemia mutations were accurately genotyped, and β-thalassemia genotypes were correctly determined in all 1022 samples, yielding overall sensitivity and specificity of 100%. The concordance rate was 99.4% between this assay and the reference method. It was concluded that the Melt-Pro HBB assay is useful for reliable genotyping of multiple β-thalassemia mutations in clinical settings and may have potential as a versatile method for rapid genotyping of known mutations because of its high throughput, accuracy, ease of use, and low cost. Copyright © 2011 American Society for Investigative Pathology and the Association for Molecular Pathology. Published by Elsevier Inc. All rights reserved. Source

Xiong F.,Southern Medical University | Sun M.,Southern Medical University | Zhang X.,The 303 Hospital of Peoples Liberation Army | Cai R.,Liuzhou Municipal Maternity and Child Healthcare Hospital | And 8 more authors.
Clinical Genetics | Year: 2010

Accurate and up-to-date data on the frequency of haemoglobinopathies among the populations of Guangxi Zhuang Autonomous Region, where haemoglobinopathies are most endemic in China, are required. In our study, a total of 5789 samples obtained from members of the Han, Zhang, and Yao ethnic groups in six geographical areas of Guangxi Province were analysed systematically in terms of both haematological and molecular parameters. The results presented that the total heterozygote frequency of thalassaemias and other haemoglobinopathies was 24.51%, of which 17.55% was due to α-thalassaemia, 6.43% to β-thalassaemia, 0.38% to structural haemoglobin variants, and 0.16% to δ-thalassaemia. The mutational spectrum among the local population for each type of disorder was described, including the first report on the true prevalence of three silent α thalassemia defects, -α3.7/(4.78%), -α4.2/(1.61%) and Hb Westmead (αWSα/) (1.57%) and of δ-thalassemia resulting from five novel and two rare mutations never before identified in Chinese individuals. Comparison of the frequencies of α-globin mutations among the ethnic groups showed that there was a statistically significant difference between the Han (15.71%) and Zhuang (20.12%), and between the Han (15.71%) and Yao (20.84%) ethnic groups. In addition, we have performed the first extensive study of haematological parameters of the Hb Westmead mutation using a group of Chinese subjects with compound heterozygosity for this variant and an α-thalassaemia deletion. The knowledge gained in this study will enable us to estimate the health burden in this high-risk population and to elucidate the various genetic alterations that underlie haemoglobinopathies. © John Wiley & Sons A/S, 2010. Source

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