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To set up a new method, which is sensitive, low cost, rapid and suitable for clinical application for FTO gene rs9930506 variant genotyping basing on high resolution melting (HRM) platform, and to preliminarily put into practice in susceptibility analysis for metabolic syndrome (MS) in Beijing. Unlabelled probe with C3-spacer block specific for rs9930506 variant has been designed according to the Refseq from GenBank. With LC-Green plus dye pre-mixed, we scanned the signal for the genotype analysis after PCR amplification and HRM reaction. Restriction fragment length polymorphism (RFLP) and PCR-sequencing methods were designed as 2 control genotyping methods for the evaluation of accuracy and convenience. Afterwards, the HRM-based method was put into practice in metabolic syndrome patients (n = 500) and control groups (n = 500) for rs9930506 genotyping, and primarily study the association between rs9930506 and MS. All the 3 methods could genotype rs9930506 appropriately, although the 2 control methods seemed to be a little time-inefficient. The call rate of HRM-method was 100% and sampling accuracy reached 99.3% according to sequencing results. In the MS group, AA, AG and GG genotypes were found in 290, 185 and 25 cases, respectively. And in the control group, those were found in 344, 138 and 18 cases. No genotype distribution difference was detected between control group and HapMap-CHB data (P = 0.520). The genotype distributions were all in Hardy-Weinberg equilibrium in each group. AA genotype of rs9930506 seemed to reduce the risk for MS (OR = 0.626, 95%CI = 0.483 - 0.812). The AA genotype of rs9930506 variant in FTO might be a protective factor for MS in Beijing population. The susceptibility related genotyping in clinical samples could be more rapid, precise and inexpensive with the development of HRM in genotyping.

Farooq M.A.,University of New Orleans | Pracheil T.M.,University of New Orleans | Dong Z.,University of New Orleans | Xiao F.,Beijing Institute of Geriatrics | Liu Z.,University of New Orleans
Oxidative Medicine and Cellular Longevity | Year: 2013

Aconitase, the second enzyme of the tricarboxylic acid cycle encoded by ACO1 in the budding yeast Saccharomyces cerevisiae, catalyzes the conversion of citrate to isocitrate. aco1Δ results in mitochondrial DNA (mtDNA) instability. It has been proposed that Aco1 binds to mtDNA and mediates its maintenance. Here we propose an alternative mechanism to account for mtDNA loss in aco1Δ mutant cells. We found that aco1Δ activated the RTG pathway, resulting in increased expression of genes encoding citrate synthase. By deleting RTG1, RTG3, or genes encoding citrate synthase, mtDNA instability was prevented in aco1Δ mutant cells. Increased activity of citrate synthase leads to iron accumulation in the mitochondria. Mutations in MRS3 and MRS4, encoding two mitochondrial iron transporters, also prevented mtDNA loss due to aco1Δ. Mitochondria are the main source of superoxide radicals, which are converted to H2O2 through two superoxide dismutases, Sod1 and Sod2. H2O2 in turn reacts with Fe2+ to generate very active hydroxyl radicals. We found that loss of Sod1, but not Sod2, prevents mtDNA loss in aco1Δ mutant cells. We propose that mtDNA loss in aco1Δ mutant cells is caused by the activation of the RTG pathway and subsequent iron citrate accumulation and toxicity. © 2013 Muhammad A. Farooq et al.

Peng D.,China Japan Friendship Hospital | Pan X.,Zhengzhou First Peoples Hospital | Cui J.,Beijing Institute of Geriatrics | Ren Y.,Henan University of Traditional Chinese Medicine | Zhang J.,Zhengzhou First Peoples Hospital
Cellular Physiology and Biochemistry | Year: 2013

Background: Alzheimer's disease (AD) is one of the most common neurodegenerative diseases. Peripheral insulin resistance increases the risk for memory impairment and the development of AD. Objective: This study aims to assess changes in cognitive functions and the level of hyperphosphorylated tau proteins in central insulin-resistant rats. Methods: An in vivo central insulin-resistant (CIR) animal model was generated through intracerebroventricular injection of streptozotocin (STZ) into insulin-resistant (IR) rats that were induced by feeding a high-glucose/-protein/-fat diet. The Morris water maze test was used to assess changes in cognitive functions, pathological changes in the cornu ammonis 1 (CA1) region of the hippocampus were detected by immunohistochemistry, and the phosphorylation levels of tau proteins at specific sites were determined by Western blot analysis. Results: The escape latency time in the Morris water maze test was significantly prolonged; the number of phosphorylated tau proteins in the CA1 region of the hippocampus was significantly increased; and the phosphorylation levels of tau proteins at Ser199, Thr205, Thr212, Thr217 and Ser396 were significantly elevated in the CIR group compared with the IR and control groups. Conclusion: This study provides direct evidence that CIR plays an important role in AD pathogenesis by facilitating tau hyperphosphorylation. © 2013 S. Karger AG, Basel.

Jiang P.,Beijing Institute of Geriatrics | Wang D.-Z.,Capital Medical University | Ren Y.-L.,Peking University | Cai J.-P.,Beijing Institute of Geriatrics | Chen B.-X.,Capital Medical University
Coronary Artery Disease | Year: 2015

BACKGROUND AND AIMS: It is well known that the interaction between platelets (PLTs), endothelial cells, and leukocytes contributes to thrombosis in patients with acute coronary syndrome. The aim of this study was to investigate the significance of PLTs and eosinophils (EOS) in coronary arterial thrombi. METHODS: PLT count, mean PLT volume, PLT mass, EOS count, EOS percentage, and troponin I level in peripheral blood were determined in 81 patients with angina pectoris (AP) and 49 patients with acute myocardial infarction (AMI). A total of 12 thrombus specimens from AMI patients were submitted for histopathological analysis. EOS presence in thrombectomy specimens were checked by hematoxylin-eosin staining and confirmed by Luna staining. RESULTS: Results showed that EOS were present in all 12 samples (100%). Cell count and percentage of EOS in peripheral blood of patients with AMI were lower than those in patients with AP (both P<0.00001). A higher PLT count was observed in AMI patients (243±70), especially among female patients or those who were older than 60 years, when compared with AP patients (216±60; all P<0.05). According to the troponin I level, we divided AMI patients into groups I (≥20ng/ml) and II (<20ng/ml). Group I had a lower EOS percentage compared with group II (P=0.0496). PLT count was also lower in group I with no statistical difference found (P=0.1202). Moreover, there was an inverse correlation between the EOS percentage and the troponin I level (r=-0.434). CONCLUSION: In conclusion, patients with AMI presented with a decreased EOS percentage and an increased PLT count. The decreased EOS percentage suggested serious myocardial damage. The study indicated that EOS play an important role in thrombosis in patients with acute coronary syndrome. Copyright © 2015 Wolters Kluwer Health, Inc. All rights reserved.

Wu T.,Beijing Institute of Geriatrics | Long X.,Beijing Normal University | Wang L.,Capital Medical University | Hallett M.,U.S. National Institutes of Health | And 3 more authors.
Human Brain Mapping | Year: 2011

Parkinson's disease (PD) patients have difficulty in initiating movements. Previous studies have suggested that the abnormal brain activity may happen not only during performance of self-initiated movements but also in the before movement (baseline or resting) state. In the current study, we investigated the functional connectivity of brain networks in the resting state in PD. We chose the rostral supplementary motor area (pre-SMA) and bilateral primary motor cortex (M1) as "seed" regions, because the pre-SMA is important in motor preparation, whereas the M1 is critical in motor execution. FMRIs were acquired in 18 patients and 18 matched controls. We found that in the resting state, the pattern of connectivity with both the pre-SMA or the M1 was changed in PD. Connectivity with the pre-SMA in patients with PD compared to normal subjects was increased connectivity to the right M1 and decreased to the left putamen, right insula, right premotor cortex, and left inferior parietal lobule. We only found stronger connectivity in the M1 with its own local region in patients with PD compared to controls. Our findings demonstrate that the interactions of brain networks are abnormal in PD in the resting state. There are more connectivity changes of networks related to motor preparation and initiation than to networks of motor execution in PD. We postulate that these disrupted connections indicate a lack of readiness for movement and may be partly responsible for difficulty in initiating movements in PD. © 2010 Wiley-Liss, Inc.

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