Application of Microhaplotypes in Sibling Kinship Testing.

OBJECTIVES: To investigate the efficacy of different numbers of microhaplotype (MH) loci and the introduction of different reference samples on the identification of full sibling, half sibling and differentiation between full sibling and half sibling kinships, and to explore the effect of changing mutation rate on sibling testing. METHODS: First, a family map involving three generations was established, and four full sibling identification models, five half sibling identification models and five models distinguishing full and half siblings were constructed for different reference samples introduced. Based on the results of the previous study, two sets of nonbinary SNP-MH containing 34 and 54 loci were selected. Based on the above MH loci, 100 000 pairs of full sibling vs. unrelated individuals, 100 000 pairs of half sibling vs. unrelated individuals and 100 000 pairs of full sibling vs. half sibling were simulated based on the corresponding sibling kinship testing models, and the efficacy of each sibling kinship testing model was analyzed by the likelihood ratio algorithm under different thresholds. The mutant rate of 54 MH loci was changed to analyze the effect of mutation rate on sibling identification. RESULTS: In the same relationship testing model, the systematic efficacy of sibling testing was positively correlated with the number of MH loci detected. With the same number of MH loci, the efficacy of full sibling testing was better than that of uncle or grandfather when the reference sample introduced was a full sibling of A, but there was no significant difference in the identification efficacy of the four reference samples introduced for full sibling and half sibling differentiation testing. In addition, the mutation rate had a slight effect on the efficacy of sibling kinship testing. CONCLUSIONS: Increasing the number of MH loci and introducing reference samples of known relatives can increase the efficacy of full sibling testing, half sibling testing, and differentiation between full and half sibling kinships. The level of mutation rate in sibling testing by likelihood ratio method has a slight but insignificant effect on the efficacy.

Factors associated with the use of percutaneous coronary intervention in elderly Chinese patients with a first ST elevated acute myocardial infarction.

INTRODUCTION: Rapid reperfusion therapies (RT), particularly percutaneous coronary intervention (PCI), improve short- and long-term outcomes in patients with ST segment elevation myocardial infarction (STEMI). However, a substantial proportion of patients with STEMI, especially older patients, refuse or do not undergo PCI. Our study aims to identify factors associated with the use of PCI in elderly Chinese patients with their first STEMI. METHOD: Elderly (aged 65 years of age or over) patients with STEMI were enrolled between March 2010 and August 2013 at two hospitals in Beijing. Patients with previous myocardial infarction and those with contraindications to reperfusion were excluded. A standardized questionnaire including onset time and severity of symptoms, history of angina pectoris, comorbid illnesses, functional status, family income, health insurance, education, patients' trust in treating physicians, and whether patient was acquainted with a cardiologist was used to collect data from patients or their family. RESULTS: Five hundred and sixty-eight patients were enrolled. PCI was accepted by 432 (76%) and refused by 136 (24%). Multivariate analysis showed that older age (>75 years; odds ratio [OR], 0.57; 95% confidence interval [CI], 0.23-0.78), self-rated mild symptoms (OR, 0.12; 95% CI, 0.06-0.21), lower degree of trust in treating physician (<6 in a 10 point scale; [OR, 0.14; 95% CI, 0.09-0.28]), and not being acquainted with a cardiologist (OR, 0.28; 95% CI, 0.07-0.42) were associated with refusal of PCI. CONCLUSION: PCI was refused by almost one quarter of eligible elderly Chinese patients with a first STEMI. Age, symptom severity, and trust in physician were independent factors associated with the use of PCI in these patients.

[Association between peroxisome proliferator-activated receptor gene single nucleotide polymorphisms and arterial stiffness in adult Chinese population].

OBJECTIVE: To analyze the association between single nucleotide polymorphisms (SNPs) of peroxisome proliferator-activated receptor(PPAR) and arterial stiffness in adult Chinese population (> 50 years). METHODS: Cardiovascular risk factors from participants of Beijing epidemiological investigation were analyzed. Carotid-femoral pulse wave velocity (cfPWV) was measured by Complior system. The subjects were divided into normal arterial stiffness group (cfPWV < 12 m/s, n = 844) and increased arterial stiffness group (cfPWV > 12 m/s, n = 530). Three valid SNPs including rs1053049, rs1800234 and rs8192678 in the PPAR and PPARγC1a gene were genotyped by TaqMan allelic discrimination assays. RESULTS: The age [(67.9 ± 8.8) years vs. (58.0 ± 9.7) years], prevalence of hypertension [71.1% (377/530) vs. 30.5% (257/844)] and diabetes mellitus [21.7% (115/530) vs. 11.0% (93/844)] were all significantly higher in increased arterial stiffness group than in normal group (all P < 0.05). The frequencies of CC, CT and TT type of rs8192678 [CC: 32.2% (272/844) vs. 30.8% (163/530), CT: 48.7% (411/844) vs. 52.1% (276/530), TT: 19.1% (161/844) vs. 17.2% (91/530)], rs1053049 [CC: 55.7% (470/844) vs. 51.3% (272/530), CT: 36.7% (310/844) vs. 39.1% (207/530), TT: 7.6% (64/844) vs. 9.6% (51/530)] and rs1800234 [CC: 88.4% (746/844) vs. 90.4% (479/530), CT + TT: 11.6% (98/844) vs. 9.6% (51/530)] were similar between the two groups. There was also no association between haplotypes and the increased arterial stiffness in this cohort. CONCLUSIONS: In this community-based population, we found that aging, hypertension and diabetes mellitus were associated but SNPs of PPAR and PPARγC1a were not associated with arterial stiffness.

[Relationship between serum N-terminal pro-brain natriuretic peptide and metabolic syndrome: a cross-sectional study].

OBJECTIVE: To explore the relationship between serum N-terminal pro-brain natriuretic peptide (NT-proBNP) and metabolic syndrome (MS). METHODS: A total of 1323 Beijing residents (559 male) were investigated. MS was defined by the modified 2004 Chinese Diabetes Society criteria and 439 cases were diagnosed as MS according to this criteria. Multivariate logistic regression analysis was used to estimate the odds ratios (OR) of MS. Multiple linear regression analysis was performed to analyze the association between NT-proBNP and characteristic variables. RESULTS: NT-proBNP was significantly lower in MS group compared to non-MS group [32.51 (29.17, 36.14) ng/L vs.38.55 (35.73, 41.50) ng/L, P = 0.012] after adjusted for age and gender. NT-proBNP level decreased with the presence of MS components (from 0 to 4 or 5) (45.92, 37.24, 35.40, 31.55 and 33.65 ng/L respectively, P = 0.043 for linear trend). Among the components, groups with larger waist circumference, higher fasting glucose and triglycerides were associated with lower NT-proBNP level. After adjustment for potential confounders, compared with the lowest NT-proBNP quartile, the adjusted odds ratio of the second, third and fourth quartile for having MS were 0.782 (95%CI: 0.544 - 1.122, P > 0.05), 0.709 (95%CI: 0.489 - 1.028, P > 0.05), 0.604 (95%CI: 0.405 - 0.900, P < 0.05), respectively. Multiple linear regression analysis showed that female gender (ß = 0.248, P < 0.001), age (ß = 0.167, P < 0.001), systolic blood pressure (ß = 0.154, P < 0.001) were positively related to NT-proBNP level while waist circumference (ß = -0.082, P = 0.004), diastolic blood pressure (ß = -0.085, P = 0.015), triglycerides (ß = -0.101, P < 0.001), total cholesterol (ß = -0.078, P = 0.004), eGFR (ß = -0.150, P < 0.001) were negatively correlated to NT-proBNP level. CONCLUSION: In this cohort, higher serum NT-proBNP concentration is associated with lower incidence of metabolic syndrome.

High-sensitive cardiac troponin T.

Cardiac troponin is the preferred biomarker for the diagnosis of acute myocardial infarction (AMI). The recent development of a high-sensitive cardiac troponin T (hs-cTnT) assay permits detection of very low levels of cTnT. Using the hs-cTnT assay improves the overall diagnostic accuracy in patients with suspected AMI, while a negative result also has a high negative predictive value. The gain in sensitivity may be particularly important in patients with a short duration from symptom onset to admission. Measurement of cardiac troponin T with the hs-cTnT assay may provide strong prognostic information in patients with acute coronary syndromes, stable coronary artery disease, heart failure and even in the general population; however, increased sensitivity comes at a cost of decreased specificity. Serial testing, as well as clinical context and co-existing diseases, are likely to become increasingly important for the interpretation of hs-cTnT assay results.

[Relationship between serum homocysteine and metabolic syndrome: a cross-sectional study].

OBJECTIVE: To explore the relationship between serum homocysteine and metabolic syndrome (MS). METHODS: A cohort with 1680 people involved in a community-based population in Beijing was investigated. Metabolic syndrome was defined by NCEP-ATPIII criteria. Multivariate logistic regression analysis was used to estimate the odds ratios (OR) of MS. Multiple linear regression analysis was performed to analyze the association between Hcy and characteristic variables. RESULTS: Homocysteine was higher in MS population compared to those without MS (17.99 µmol/L vs. 17.18 µmol/L, P=0.007) after adjusted for age and sex. Levels of homocysteine increased with the presence of MS components (from 0 to 4 or 5) (16.71, 16.94, 17.62, 18.20, 17.82 µmol/L respectively, P=0.044 for linear trend). Among the components, groups with larger waist circumference, higher blood pressure and triglycerides showed significantly higher Hcy level than their counterparts. RESULTS: from multiple logistic regression analysis revealed that the highest Hcy quartile (Hcy IV) was significantly associated with MS. Compared with the lowest Hcy quartile (Hcy I), the adjusted odds ratio of having MS in HcyIV was 1.379 (1.005-1.892) after adjusting for age, sex, levels on creatinine/estimated glomerular filtration rate (eGFR)/low-density lipoprotein cholesterol (LDL-C) and uric acid, smoking, alcohol intake and exercise. In the partial correlation analyses, Hcy was positively associated with body mass index (BMI), waist circumsternece, blood pressure, LDL-C, triglycerides (TG), uric acid, serum creatinine, eGFR, but inversely associated with high-density lipoprotein cholesterol (HDL-C) and independently with age and sex. In multiple linear regression analysis, age, male sex, BMI, LDL-C, creatinine and uric acid were found to be independently associated with Hcy level. CONCLUSION: There was an association noticed between the MS using NCEP-ATPIII criteria and the highest quartile level of Hcy in this study. Factors as age and being male, the levels of BMI, LDL-C, creatinine and uric acid were independently associated with the Hcy level.

Associations of plasma homocysteine and high-sensitivity C-reactive protein levels with arterial stiffness in Chinese population: a community-based study.

BACKGROUND: Arterial stiffness increases with age and is also associated with traditional cardiovascular risk factors. Little is known about the relations of homocysteine and high-sensitivity C-reactive protein (hs-CRP) to arterial stiffness in the Chinese community. The aim of the present study was to investigate the association of plasma homocysteine and hs-CRP levels with arterial stiffness in a community-based cohort. METHODS: We related levels of homocysteine and hs-CRP to four measures of arterial stiffness (carotid-femoral pulse wave velocity (PWV), carotid-radial PWV, carotid-ankle PWV and heart rate corrected augmentation index) in 1680 participants from two communities of Beijing, China. Arterial stiffness was measured within two days of the time of biomarker measurement. RESULTS: In univariate analysis, homocysteine was positively associated with the carotid-femoral PWV (r = 0.211, P < 0.0001), carotid-radial PWV (r = 0.120, P < 0.0001) and carotid-ankle PWV (r = 0.148, P < 0.0001), whereas it was inversely related to the augmentation index (r = -0.052, P = 0.016). Hs-CRP was positively associated with the carotid-femoral PWV (r = 0.074, P = 0.001) and carotid-ankle PWV (r = 0.050, P = 0.02). In multiple-adjusted models (R(2) = 0.57), homocysteine levels remained a significant determinant of the carotid-femoral PWV (standardized ß = 0.065, P = 0.007), whereas the association of hs-CRP with measurements of arterial stiffness was not present. CONCLUSIONS: In the Chinese population, plasma homocysteine levels are associated with alterations of aortic stiffness, whereas plasma levels of hs-CRP are not independently related to artery stiffening.

The apelin-APJ pathway exists in cardiomyogenic cells derived from mesenchymal stem cells in vitro and in vivo.

Our previous study demonstrated that apelin level increased significantly after the treatment of intracoronary implantation of bone marrow mononuclear cells (BMMCs), followed by the improvement of cardiac function in patients with severe ischemic heart failure. The present studies both in vivo and in vitro explored whether mesenchymal stem cells derived from bone marrow (BMSCs) activate the apelin-APJ pathway when differentiating into cardiomyogenic cells. Isolated BMSCs from rat femurs and tibias were cultured and expanded for three passages, labeled with DAPI, and treated with 5-azacytidine (5-AZ). BMSCs labeled with ad-EGFP were injected intramyocardially into the peri-infarct area of rat models with acute myocardial infarction. Immunofluorescence staining exposed that CMGs expressed apelin together with myogenic-specific proteins such as α-actin, troponin T, GATA-4, and connexin-43 at 7 days after 5-AZ treatment or EGFP-BMSC injection. RT-PCR revealed that mRNA in CMGs started to express apelin and APJ from day 7 and progressively increased until day 28. Cardiac function, as measured by echocardiography in vivo, was significantly improved in parallel with the extent of apelin expression after BMSC transplantation. Our finding indicated that the expression of the apelin-APJ pathway during differentiation of BMSCs into CMGs may be an important mechanism in regulation of myocardial regeneration and functional recovery after BMSC transplantation.

Increased apelin following bone marrow mononuclear cell transplantation contributes to the improvement of cardiac function in patients with severe heart failure.

We previously reported that intracoronary implantation of bone marrow mononuclear cells (BMMC) into ischemic hearts improved cardiac function after myocardial infarction. However, the mechanisms have not been elucidated. The present study investigates whether apelin, a newly described inotropic peptide with important cardiovascular regulatory properties, contributes to the functional improvement in patients with severe heart failure after cell transplantation. Forty consecutive patients with severe heart failure secondary to myocardial infarction were assigned to the BMMC therapy group or the standard medication group according to each patient's decision on a signed consent document. In 20 patients intracoronary cell infusion was performed, and another 20 patients were matched to receive standard medication as therapeutic controls. An additional 20 healthy subjects were designated as normal controls. Clinical manifestations, echocardiograms, and biochemical assays were recorded. Plasma apelin and brain natriuretic protein (BNP) levels were determined by enzyme immunoassay. Baseline levels of plasma apelin were significantly lower in all heart failure patients compared to normal subjects. In patients who underwent cell transplantation, apelin increased significantly from 3 to 21 days after operation, followed by significant improvement in cardiac function. In parallel, BNP varied inversely with the increase of apelin. In patients receiving standard medical treatment, apelin remained at a lower level. Our findings indicated that increased apelin levels following cell therapy may act as a paracrine mediator produced from BMMCs and play an important role in the treatment of heart failure through autocrine and paracrine mechanisms.

[Transfection of bone marrow mesenchymal stem cells by adeno-associated virus 2/1 vector].

This study was aimed to investigate the transfection efficacy of recombinant adeno-associated virus 2/1 (rAAV2/1) on bone marrow mesenchymal stem cells (BMMSCs) at different multiplicities of infection (MOI) and time, and effect of transfection on growth of rat BMMSCs. The rat BMMSCs cultured in vitro were transfected by using rAAV2/1 with enhanced green fluorescent protein (rAAV2/1-EGFP) at MOI of 1 x 10(4), 1 x 10(5) and 1 x 10(6); the EGFP expression was observed by fluorescent microscopy at 3, 7 and 14 days. The viability, proliferation multiple, differentiation ability of daughter cells were detected for evaluating the effect of rAAV2/1 on survival, proliferation and differentiation of BMMSCs and the fluorescence index (FI) were determined by flow cytometry. The results indicated that after transfection with rAAV2/1 for 24 hours the green fluorescence in BMMSCs were observed, but also the fluorescence gradually was enhanced along with prolonging of time, and reached to steady level after 7 days; the viability, proliferation multiple, differentiation ability of BMMSCs transfected by rAAV2/1-EGFP at different MOI showed no significant changes at 3,7 and 14 days (p > 0.05), meanwhile at same MOI the proliferation multiple obviously increased in comparison between 7 day vs 3 day and 14 days vs 7 days (p < 0.01). The flow cytometric detection showed that the transfection efficacy of rAAV2/1-EGFP on BMMSCs and FI increased significantly as the multiplicity of infection and culture time increased (p < 0.05). It is concluded that rAAV2/1-EGFP is able to transfect into BMMSCs effectively, but the transfection efficiency and fluorescence index increase significantly along with increase of multiplicity of infection and culture time. rAAV2/1-EGFP do not affect viability, proliferation multiple and differentiation ability of BMMSCs. rAAV2/1 is a kind of active vector for gene transfer to reform BMMSCs.