Chunhui Jin

Effect of low-frequency rTMS on aphasia in stroke patients: a meta-analysis of randomized controlled trials.

Background Small clinical trials have reported that low-frequency repetitive transcranial magnetic stimulation (rTMS) might improve language recovery in patients with aphasia after stroke. However, no systematic reviews or meta-analyses studies have investigated the effect of rTMS on aphasia. The objective of this study was to perform a meta-analysis of studies that explored the effects of low-frequency rTMS on aphasia in stroke patients. Methods We searched PubMed, CENTRAL, Embase, CINAHL, ScienceDirect, and Journals@Ovid for randomized controlled trials published between January 1965 and October 2013 using the keywords “aphasia OR language disorders OR anomia OR linguistic disorders AND repetitive transcranial magnetic stimulation OR rTMS”. We used fixed- and random-effects models to estimate the standardized mean difference (SMD) and a 95% CI for the language outcomes. Results Seven eligible studies involving 160 stroke patients were identified in this meta-analysis. A significant effect size of 1.26 was found for the language outcome severity of impairment (95% CI = 0.80 to 1.71) without heterogeneity (I2 = 0%, P = 0.44). Further analyses demonstrated prominent effects for the naming subtest (SMD = 0.52, 95% CI = 0.18 to 0.87), repetition (SMD = 0.54, 95% CI = 0.16 to 0.92), writing (SMD = 0.70, 95% CI = 0.19 to 1.22), and comprehension (the Token test: SMD = 0.58, 95% CI = 0.07 to 1.09) without heterogeneity (I2 = 0%). The SMD of AAT and BDAE comprehension subtests was 0.32 (95% CI = −0.08 to 0.72) with moderate heterogeneity (I2 = 32%,P = 0.22). The effect size did not change significantly even when any one trial was eliminated. None of the patients from the 7 included articles reported adverse effects from rTMS. Conclusions Low-frequency rTMS with a 90% resting motor threshold that targets the triangular part of the right inferior frontal gyrus (IFG) has a positive effect on language recovery in patients with aphasia following stroke. Further well-designed studies with larger populations are required to ascertain the long-term effects of rTMS in aphasia treatment.

Meta-analysis of association between the -1438A/G (rs6311) polymorphism of the serotonin 2A receptor gene and major depressive disorder

Abstract Objectives: Major depressive disorder (MDD) is a severe psychiatric disorder with a lifetime prevalence of approximately 10–15%. Previous pharmacological studies suggested that the serotonin 2A receptor (5-HTR2A) was one of the major pharmacological therapeutic targets for MDD. Recently, genetic studies investigated the association between the polymorphism rs6311 of the 5-HTR2A gene and MDD. However, the results of these studies were inconsistent. To evaluate these conflicting findings, we performed the current meta-analysis. Methods: Eleven articles form PubMed and Chinese National Knowledge Infrastructure databases were selected including 1491 patients and 2937 controls for the meta-analysis through assessing in detail. All statistical analyses were performed by RevMan (v.5·1) program. Results: No significant association between the 5-HTR2A gene SNP rs6311 and the risk of MDD was observed by four genetic models in the current meta-analysis (P = 0·12 for A versus G; P = 0·11 for AA versus GG; P = 0·06 for AA+AG versus GG; P = 0·24 for AG+GG versus AA). The calculated generalized odds ratio also revealed that the SNP rs6311 did not confer an increased risk to MDD. Moreover, the sensitivity analysis indicated that the result of meta-analysis is instable. Conclusions: Although the current meta-analysis indicated that the SNP rs6311 within the 5-HTR2A gene may be not associated with an increased risk for MDD, the results require further study to acquire more direct evidence.

Replication Study Confirms Link between TSPAN18 Mutation and Schizophrenia in Han Chinese

Schizophrenia (SCZ) is a severe psychiatric disorder associated with many different risk factors, both genetic and environmental. A recent genome-wide association study (GWAS) of Han Chinese identified three single-nucleotide polymorphisms (SNPs rs11038167, rs11038172, and rs835784) in the tetraspanins gene TSPAN18 as possible susceptibility loci for schizophrenia. Hoping to validate these findings, we conducted a case-control study of Han Chinese with 1093 schizophrenia cases and 1022 healthy controls. Using the LDR-PCR method to genotype polymorphisms in TSPAN18, we found no significant differences (P>0.05) between patients and controls in either the allele or genotype frequency of the SNPs rs11038167 and rs11038172. We did find, however, that the frequency of the ‘A’ allele of SNP rs835784 is significantly higher in patients than in controls. We further observed a significant association (OR  = 1.197, 95%CI  = 1.047–1.369) between risk for SCZ and this ‘A’ allele. These results confirm the significant association, in Han Chinese populations, of increased SCZ risk and the variant of the TSPAN18 gene containing the ‘A’ allele of SNP rs835784.

Association of the CR1 polymorphism with late-onset Alzheimer's disease in Chinese Han populations: A meta-analysis

It is well known that genetic variants play a critical role in the pathogenesis of Alzheimers disease (AD). In 2009, a genome-wide association study (GWAS) demonstrated that a single nucleotide polymorphism (SNP), rs6656401, in complement receptor 1 (CR1) is significantly associated with late-onset Alzheimers disease (LOAD) in Caucasian population. Subsequently, other researchers have attempted to validate this finding in Chinese Han populations. However, these findings in Chinese Han populations have produced both negative and positive results. To derive a more precise estimation for the relationship, we performed the present meta-analysis by analyzing three published association studies involving CR1 SNP rs6656401 through the use of the RevMan (v.5.1) program. Pooled odds ratios (ORs) were calculated for allele contrasts (A vs. G) and a dominant model [(AA+AG) vs. GG] in three studies that included 1019 cases and 1080 controls, respectively. The statistical results showed a significant difference between patients and controls for the A allele of CR1 SNP rs6656401 (P=0.005). In addition, carriers of the A allele (AA+AG) of rs6656401 had a 1.69-fold increased risk for LOAD compared with non-carriers (GG) (P=0.01). In conclusion, despite there are some limitations, this meta-analysis indicates that the A allele of the CR1 SNP rs6656401 is significantly associated with LOAD susceptibility in Chinese Han populations.

Abnormal functional connectivity of brain network hubs associated with symptom severity in treatment-naive patients with obsessive-compulsive disorder: A resting-state functional MRI study.

OBJECTIVE Abnormal brain networks have been observed in patients with obsessive-compulsive disorder (OCD). However, detailed network hub and connectivity changes remained unclear in treatment-naive patients with OCD. Here, we sought to determine whether patients show hub-related connectivity changes in their whole-brain functional networks. METHODS We used resting-state functional magnetic resonance imaging data and voxel-based graph-theoretic analysis to investigate functional connectivity strength and hubs of whole-brain networks in 29 treatment-naive patients with OCD and 29 age- and gender-matched healthy controls. Correlation analysis was applied for potential associations with OCD symptom severity. RESULTS OCD selectively targeted brain regions of higher functional connectivity strength than the average including brain network hubs, mainly distributed in the cortico-striato-thalamo-cortical (CSTC) circuits and additionally parietal, occipital, temporal and cerebellar regions. Moreover, affected functional connectivity strength in the cerebellum, the medial orbitofrontal cortex and superior occipital cortex was significantly associated with global OCD symptom severity. CONCLUSION Our results provide the evidence about OCD-related brain network hub changes, not only in the CSTC circuits but more distributed in whole brain networks. Data suggest that whole brain network hub analysis is useful for understanding the pathophysiology of OCD.

An Updated Meta-Analysis of the Association between SORL1 Variants and the Risk for Sporadic Alzheimer's Disease

The pathogenetic mechanism of Alzheimers disease (AD) is still unknown; however, genetic variants play a critical role in the pathogenesis of AD. It has been reported that single nucleotide polymorphisms (SNPs) of the sortilin-related receptor with A-type repeats (SORL1, also called LR11 or sorLA) are associated with late-onset AD in Caucasian populations. Subsequently, other researchers have attempted to validate this finding in different ethnic populations. However, these findings have produced both negative and positive results. To derive a more precise estimation of whether SORL1 variants are associated with sporadic AD (SAD), we performed the meta-analysis presented in this manuscript. Databases including PubMed, AlzGene, the China National Knowledge Infrastructure (CNKI), and Wan Fang were searched to find relevant studies. Odds ratios (ORs) with 95% confidence intervals (CIs) were used to assess the strength of the association studies. A total of twenty-three case-control studies involving 11,837 cases and 20,022 controls were included. Among the eleven candidate SNPs highlighted in the previous study, four SNPs (SNP 4, SNP 5, SNP 8 and SNP 10) showed a significant association with SAD using a generalized odds ratio (ORG, a model-free approach) and linkage disequilibrium structure analysis. Meanwhile, no significant heterogeneity between the Caucasian and Asian populations for the associated SNPs was observed in the current meta-analysis. Moreover, we further confirmed that the SORL1 three-marker haplotype C-G-C at SNP 8-SNP 9-SNP 10 was significantly associated with SAD (OR = 1.37, 95% CI = 1.12-1.66, padj = 0.008). The current meta-analysis further supports the previous findings that the SORL1 gene may be associated with SAD risk.

Exploring Transcription Factors-microRNAs Co-regulation Networks in Schizophrenia

BACKGROUND Transcriptional factors (TFs) and microRNAs (miRNAs) have been recognized as 2 classes of principal gene regulators that may be responsible for genome coexpression changes observed in schizophrenia (SZ). METHODS This study aims to (1) identify differentially coexpressed genes (DCGs) in 3 mRNA expression microarray datasets; (2) explore potential interactions among the DCGs, and differentially expressed miRNAs identified in our dataset composed of early-onset SZ patients and healthy controls; (3) validate expression levels of some key transcripts; and (4) explore the druggability of DCGs using the curated database. RESULTS We detected a differential coexpression network associated with SZ and found that 9 out of the 12 regulators were replicated in either of the 2 other datasets. Leveraging the differentially expressed miRNAs identified in our previous dataset, we constructed a miRNA-TF-gene network relevant to SZ, including an EGR1-miR-124-3p-SKIL feed-forward loop. Our real-time quantitative PCR analysis indicated the overexpression of miR-124-3p, the under expression of SKIL and EGR1 in the blood of SZ patients compared with controls, and the direction of change of miR-124-3p and SKIL mRNA levels in SZ cases were reversed after a 12-week treatment cycle. Our druggability analysis revealed that many of these genes have the potential to be drug targets. CONCLUSIONS Together, our results suggest that coexpression network abnormalities driven by combinatorial and interactive action from TFs and miRNAs may contribute to the development of SZ and be relevant to the clinical treatment of the disease.

A competitive PCR assay confirms the association of a copy number variation in the VIPR2 gene with schizophrenia in Han Chinese

Evidence from genetic studies has revealed that genome-wide rare copy number variations (CNVs) are risk factors for neurodevelopmental disorders and this evidence has given rise to a new understanding of disease etiology, including that of schizophrenia (SCZ). Recent studies have indicated that duplication in the vasoactive intestinal peptide receptor-2 (VIPR2) gene confers the susceptibility to SCZ in Caucasians, but so far this finding has still not been confirmed in Chinese populations. In this study, we investigated the association between CNVs in VIPR2 and SCZ risk in an independent case-control study of Han Chinese using 1035 cases and 1535 controls. The CNVs were genotyped using the multiplex fluorescence competitive PCR method. In contrast with a common genotype (2-copy), a microduplication variant genotype (3-copy) was only carried by SCZ patients (4/1035). This finding indicated that CNVs in VIPR2 may impose a significantly increased risk of SCZ in Han Chinese (P=0.02646, OR=infinity, 95% CI=1.327-infinity). Thus, our results suggest that carriers of microduplication genotypes of VIPR2 are predisposed to SCZ in Han Chinese.

Lack of association between MPC2 variants and schizophrenia in a replication study of Han Chinese

Schizophrenia (SCZ) is a common, complex and severe psychiatric disorder associated with many different risk factors, both genetic and environmental. A recent genome-wide association study (GWAS) of Han Chinese identified a single-nucleotide polymorphism (SNP, rs10489202) in the mitochondrial pyruvate carrier 2 gene (MPC2, also known as BRP44) as a possible susceptibility locus for schizophrenia. Hoping to validate this finding, we conducted a case-control study of Han Chinese with 1093 schizophrenia cases and 1022 healthy controls, using the LDR-PCR method to genotype polymorphisms (rs10489202 and a TagSNP rs203861) in the MPC2 gene. However, we found no significant difference (P>0.05) in either allele or genotype frequency in the SNPs between patients and controls. These results did not support the previous finding suggesting the further study by using a large-scale association analysis in the future should be warranted in Han Chinese populations.

Altered expression of mRNA profiles in blood of early-onset schizophrenia

To identify gene expression abnormalities in schizophrenia (SZ), we generated whole-genome gene expression profiles using microarrays on peripheral blood mononuclear cells (PBMCs) from 18 early-onset SZ cases and 12 controls. We detected 84 transcripts differentially expressed by diagnostic status, with 82 genes being upregulated and 2 downregulated. We identified two SZ associated gene coexpression modules (green and red), including 446 genes . The green module is positively correlated with SZ, encompassing predominantly up-regulated genes in SZ; while the red module was negatively correlated with disease status, involving mostly nominally down-regulated genes in SZ. The olfactory transduction pathway was the most enriched pathways for the genes within the two modules. The expression levels of several hub genes, including AKT1, BRCA1, CCDC134, UBD, and ZIC2 were validated using real-time quantitative PCR. Our findings indicate that mRNA coexpression abnormalities may serve as a promising mechanism underlying the development of SZ.