Biomedical subjects

Xinchun Yang

Publications and source records attributed to Xinchun Yang.

3 recordsLinked to original sources

PubMed2004

Nonlinear processing and analysis of ECG data.

A new approach based on a histogram analysis to detect QRS-T complexes of the ECG curve rapidly and reliably is described. The aim consists of a rapid and reliable detection of the P-wave (when atrial fibrillation, AF, is absent) or the f-wave (when AF happens). By means of signal processing techniques such as the fractal dimension method and the Shannon entropy method, two types of ECG signals (with or without AF) were analysed and the significant differences between them documented. Accordingly, the methods allow to determine easily whether AF occurs or not.

Electrocardiography↗

PubMed2003

Relationships among apolipoprotein A1 gene polymorphisms, lipid levels and coronary atherosclerosis disease.

OBJECTIVE: To investigate the relationship among -75 bp/+83 bp polymorphism in apolipoprotein A1 (apo A1) gene, lipids levels and the occurrence of coronary atherosclerosis disease (CAD). METHODS: We determined distributions of two MspI polymorphisms of the apo A1 gene at -75 bp and +83 bp, and blood lipids levels among 137 Chinese patients (92 with CAD and 45 in the control group) in relation to circulating lipids and coronary angiography. RESULTS: The demographic information for 137 subjects showed that subjects with CAD tended to have more unfavorable lipoprotein variables. Genotype distributions at both sites were different between the CAD and control groups. Furthermore, the control group had higher M1-/M2- frequencies than the CAD group (M1: P < 0.005; M2: P < 0.05) and the "M1-" (A) and "M2-" alleles were associated with increased high-density lipoprotein cholesterol (HDL-C) (M1-: P < 0.0001; M2-: P < 0.05) and apo A1 (M1-: P < 0.0001; M2-: P < 0.05) levels. "M1-" and "M2-" were significantly negatively correlated with CAD (P < 0.01 and P < 0.05, respectively). CONCLUSIONS: Our results suggest that changes from G to A at the -75 bp site and from C to T or G to A at the +83 bp site do increase circulating levels of apo A1 and HDL-C. And those individuals with these changes are likely to have a lower risk of developing CAD.

Apolipoprotein A-I↗

PubMed2002

Autoantibodies against the myocardial beta1-adrenergic and M2-muscarinic receptors in patients with congestive heart failure.

OBJECTIVE: To determine whether autoantibodies against beta(1)-adrenergic and M(2)-muscarinic receptors are related to patients with congestive heart failure (CHF). METHODS: Both synthetic peptides corresponding to amino acids sequence 197-222 and 169-173 of the second extracellular loops of the beta(1) and M(2) receptors were used as antigens to screen sera from 265 patients.188 were congestive heart failure ( CHF) patients with different heart diseases, among them 42 were ischemic cardiomyopathy (ICD) and 52 were idiopathic dilated cardiomyopathy (IDCM) 44 were hypertensive heart disease (HHD) 50 were rheumatic valvular heart disease (RVHD); 77 were controls, among them 36 were simple hypertension and 41 were healthy donors (NC). RESULTS: Positive sera for beta(1)-adrenergic receptor was found in 45.73% (86/188) of CHF patients, while in the controls it was 10.4% (8/77) (P < 0.01); positive sera for M(2)-muscarinic receptor in CHF patients was found in 49.5% (99/188), while in the control it was 11.7% (9/77) (P < 0.01). The positive ratio of autoantibodies against beta(1)-adrenergic and M(2)-muscarinic receptors in CHF patients with cardiac function class II-III (NYHA) were significantly higher than cardiac function class IV. The average titer of autoantibodies against beta(1)-adrenergic and M(2)-muscarinic receptors of the former was significantly higher than the latter; 56.1% of patients with autoantibodies against beta(1)-adrenergic receptor had autoantibodies against M(2)-muscarinic receptor. CONCLUSIONS: Autoantibodies against beta(1)-adrenergic receptor and M(2)-muscarinic receptor were found in sera from heart failure patients with different cardiac diseases. We propose that autoantibodies against beta(1) and M(2) receptors are not only related to the IDCM, but also to cardiac structural and functional changes.

Adult↗