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Background/Aims: There is growing evidence that the RE1-silencing transcription factor (REST) gene may contribute to cognitive aging and Alzheimer diseases. In this replication study, we reassessed whether single nucleotide polymorphisms (SNPs) within the REST gene are linked with cognitive aging independently and/or through complex interactions in an older Taiwanese population. Methods: A total of 634 Taiwanese subjects aged over 60 years from the Taiwan Biobank were analyzed. Mini-Mental State Examination (MMSE) scores were performed for all subjects to weigh cognitive functions. Results: Our data showed that the REST rs1277306 SNP was significantly associated with cognitive aging among all subjects (p = 0.0052). Furthermore, the association remained significant for individuals without APOE ε4 allele (p = 0.0092), but not for individuals with at least 1 APOE ε4 allele. This association remained significant after Bonferroni correction. Additionally, we found the interactions between the rs1713985 and rs1277306 SNPs on cognitive aging (p = 0.016). However, the 3-marker haplotype derived from the rs1713985, rs3796529, and rs7680734 SNPs in the REST gene demonstrated no association with cognitive aging. Conclusion: Our study indicates that the REST gene may contribute to susceptibility to cognitive aging independently as well as through SNP-SNP and APOE - REST interactions. [ABSTRACT FROM AUTHOR]

Abstract: The nonlinear properties of spontaneous fluctuations in blood oxygen level-dependent (BOLD) signals remain unexplored. We test the hypothesis that complexity of BOLD activity is reduced with aging and is correlated with cognitive performance in the elderly. A total of 99 normal older and 56 younger male subjects were included. Cognitive function was assessed using Cognitive Abilities Screening Instrument and Wechsler Digit Span Task. We employed a complexity measure, multiscale entropy (MSE) analysis, and investigated appropriate parameters for MSE calculation from relatively short BOLD signals. We then compared the complexity of BOLD signals between the younger and older groups, and examined the correlation between cognitive test scores and complexity of BOLD signals in various brain regions. Compared with the younger group, older subjects had the most significant reductions in MSE of BOLD signals in posterior cingulate gyrus and hippocampal cortex. For older subjects, MSE of BOLD signals from default mode network areas, including hippocampal cortex, cingulate cortex, superior and middle frontal gyrus, and middle temporal gyrus, were found to be positively correlated with major cognitive functions, such as attention, orientation, short-term memory, mental manipulation, and language. MSE from subcortical regions, such as amygdala and putamen, were found to be positively correlated with abstract thinking and list-generating fluency, respectively. Our findings confirmed the hypothesis that complexity of BOLD activity was correlated with aging and cognitive performance based on MSE analysis, and may provide insights on how dynamics of spontaneous brain activity relates to aging and cognitive function in specific brain regions. [Copyright &y& Elsevier]

Objective: Depression and anxiety frequently co-occur in patients with cirrhosis, but their underlying biological substrates are unclear. There is now evidence to suggest that depression is accompanied by signs of an immune response. This study investigated the correlation between depression/anxiety and T-lymphocyte subsets in liver cirrhosis patients. Methods: A total of 59 patients (37 males and 22 females; aged between 26-81 years) with cirrhosis were enrolled in the study. Severity of depression and anxiety were assessed through the Hamilton depressive scale (HAMD, the 24-item version) and the Hamilton anxiety scale (HAMA). T-lymphocyte subsets (CD3, CD4, and CD8) in peripheral blood were determined by flow cytometry. The relationship between lymphocyte subsets and depression/anxiety scores was studied by correlation analysis. Results: The mean total HAMD and HAMA scores for the 59 subjects were 12.8 ± 10.4 (range = 0-46) and 7.0 ± 5.7 (range = 0-26), respectively. Fourteen of 59 subjects (23.7%) had HAMD scores equal to or above 20, indicative of depression. The percentage of CD8, but not CD3 or CD4, in T-lymphocyte subsets was positively correlated with depression (HAMD) (r = 0.268, P = 0.043) and anxiety severity (HAMA) (r = 0.321, P = 0.013). After controlling for age and Child-Pugh scores, the correlations were still significant. Conclusion: Around one-fourth of cirrhosis patients may have depression, although depression is not related to cirrhosis severity. Our findings are the first to show that depression and anxiety may be associated with increased levels of CD8 in T-lymphocyte subsets in cirrhosis patients, suggesting that an imbalance of T-lymphocyte subsets may be a factor facilitating depression and anxiety in cirrhotic patients. Examination of CD8 T-lymphocytes may prove useful in assessing the potential relationship between depression, anxiety, immunity, and liver cirrhosis. [ABSTRACT FROM AUTHOR]

Abstract: Background: Although Internet has become an important source for affected people seeking suicide information, the connection between Internet searches for suicide information and suicidal death remains largely unknown. This study aims to evaluate the association between suicide and Internet searches trends for 37 suicide-related terms representing major known risks of suicide. Methods: This study analyzes suicide death data in Taipei City, Taiwan and corresponding local Internet search trend data provided by Google Insights for Search during the period from January 2004 to December 2009. The investigation uses cross correlation analysis to estimate the temporal relationship between suicide and Internet search trends and multiple linear regression analysis to identify significant factors associated with suicide from a pool of search trend data that either coincides or precedes the suicide death. Results: Results show that a set of suicide-related search terms, the trends of which either temporally coincided or preceded trends of suicide data, were associated with suicide death. These search factors varied among different suicide samples. Searches for “major depression” and “divorce” accounted for, at most, 30.2% of the variance in suicide data. When considering only leading suicide trends, searches for “divorce” and the pro-suicide term “complete guide of suicide,” accounted for 22.7% of variance in suicide data. Conclusions: Appropriate filtering and detection of potentially harmful source in keyword-driven search results by search engine providers may be a reasonable strategy to reduce suicide deaths. [Copyright &y& Elsevier]