PubMed Health⌕ Search

Biomedical subjects

Guo-qing Zhang

Publications and source records attributed to Guo-qing Zhang.

6 recordsLinked to original sources

Operon prediction based on SVM.

The operon is a specific functional organization of genes found in bacterial genomes. Most genes within operons share common features. The support vector machine (SVM) approach is here used to predict operons at the genomic level. Four features were chosen as SVM input vectors: the intergenic distances, the number of common pathways, the number of conserved gene pairs and the mutual information of phylogenetic profiles. The analysis reveals that these common properties are indeed characteristic of the genes within operons and are different from that of non-operonic genes. Jackknife testing indicates that these input feature vectors, employed with RBF kernel SVM, achieve high accuracy. To validate the method, Escherichia coli K12 and Bacillus subtilis were taken as benchmark genomes of known operon structure, and the prediction results in both show that the SVM can detect operon genes in target genomes efficiently and offers a satisfactory balance between sensitivity and specificity.

Bacillus subtilis↗

[In utero ethanol exposure alters the mitochondrial protein expression of fetal mouse cerebrum].

OBJECTIVE: To probe the effect of prenatal ethanol exposure on the mitochondrial protein expression in fetal mouse cerebrum. METHODS: Pregnant CD-1 mice were given 5.0 g/kg ethanol intragastrically from pregnant days (PD) 6-15. Fetal cerebral mitochondria were isolated on PD 18. The overall mitochondrial protein was applied to two-dimensional gel electrophoresis. Differentially expressed protein spots were cut off and identified by matrix-assisted laser desorption ionization time-of-flight (MALDI-TOF) mass spectrometry. Activities of respiratory chain complex IV (72.3%+/-4.6% of control) and ATP synthase, and ATP content in the fetal cerebral cells were measured. RESULTS: Expressions of some constructional and functional proteins were altered by in utero ethanol exposure. Activities of respiratory chain complex IV and ATP synthase (80.3%+/-5.1% of control) were both decreased. ATP content (67.9%+/-3.9% of control) in the cerebral cells was reduced in the in utero ethanol exposure fetuses. CONCLUSION: In utero ethanol exposure affects the mitochondrial protein expression of fetal mouse cerebrum, even in the tissue without obvious morphological malformations, which may be a possible mechanism of behavioral defects found in children with prenatal ethanol exposure.

Animals↗

[Study on the clinical epidemiology of systemic lupus erythematosus among 1433 cases].

OBJECTIVE: To explore factors that affecting the outcome of systemic lupus erythematosus (SLE) therapy. METHODS: Factors on the results of therapy were analysed through a case-control study. RESULTS: The common symptoms of SLE were fever, joint pain and skin eruption on face while the common provocation factors of SLE were infection and birth. Through multivariate logistic regression analyses, factors that influencing SLE result of treatment were tachycardia, diastolic pressure step-up, complement C(3) reduction, anti-ds-DNA antibody, SLE relapse and brain syndrome with the OR values as 2.28, 2.34, 2.42, 2.47, 1.98 and 5.56, respectively. CONCLUSION: The symptom and clinical characteristics of SLE were complicated. SLE treatment result could be influenced by tachycardia, diastolic pressure step-up, complement C(3) reduction, anti-ds-DNA antibody, SLE relapse and brain syndrome suggesting that the prognosis of SLE patients should be comprehensively considered.

Adolescent↗

[The analysis on single nucleotide polymorphism of PDCD1 and systemic lupus erythematous susceptibility among Han indigenous in Chinese population].

OBJECTIVE: To explore the frequencies and polymorphic distribution of intron 4 of programmed cell death 1 (PDCD1) gene, and to analyze its relation to the susceptibility of developing systemic lupus erythematosus (SLE) in indigenous Han Chinese from Anhui province. METHODS: Blood samples from 122 patients with confirmed SLE and 143 controls were collected for a case-control study. DNA of the subjects was extracted and amplified by polymerase chain reaction (PCR). The single nucleotide polymorphisms(SNPs) of PDCD1 7809 locus,7872 locus and 8162 locus were further confirmed by direct DNA sequencing and BLAST. RESULTS: The PDCD1 7809 locus was indentified as type G/G among all the subjects investigated. There were significant difference at PDCD1 7872 locus with C/T polymorphism and 8162 locus with G/A polymorphism between SLE patients and controls (Chi2 = 8.55, chi2 = 11.85, P<0.05). The frequencies of genotype for 7872 locus with types of C/C, C/T and T/T in SLE patients were 36.1% 41.8% and 22.1%, while in control they were 51.7%, 35.0% and 13.3%, respectively. There was significant difference in the frequency of mutation in 7872 locus between SLE patients and controls (chi2 = 7.411, P<0.05). The genotype frequencies of PDCD1 8162 locus G/G, G/A and A/A in SLE patients were 50.1%, 20.3% and 28.6%, while in control they were 57.6%, 20.8% and 22.6%, respectively. There was significant difference in the frequency of mutation in 8162 locus alleles between SLE patients and controls (chi2 =7.547, P<0.05). The genetypeof PDCD1-7809(C/T) and PDCD1-8162(G/A) seemed to have the function of preventing the development of SLE ( OR = 0.583, OR = 0.485). CONCLUSION: The genotype of PDCD1 gene 7809 locus was G/G in all indigenous Han Chinese, while the SNPs of PDCD1 gene 7872 locus and 8162 locus might affect the susceptibility to SLE development.

Adult↗

[Influences of environmental factors and interaction of several chemokines gene-environmental on systemic lupus erythematosus].

OBJECTIVE: To explore the impact of environmental factors, daily lifestyle, psycho-social factors and the interactions between environmental factors and chemokines genes on systemic lupus erythematosus (SLE). METHODS: Case-control study was carried out and environmental factors for SLE were analyzed by univariate and multivariate unconditional logistic regression. Interactions between environmental factors and chemokines polymorphism contributing to systemic lupus erythematosus were also analyzed by logistic regression model. RESULTS: There were nineteen factors associated with SLE when univariate unconditional logistic regression was used. However, when multivariate unconditional logistic regression was used, only five factors showed having impacts on the disease, in which drinking well water (OR=0.099) was protective factor for SLE, and multiple drug allergy (OR=8.174), over-exposure to sunshine (OR=18.339), taking antibiotics (OR=9.630) and oral contraceptives were risk factors for SLE. When unconditional logistic regression model was used, results showed that there was interaction between eating irritable food and -2518MCP-1G/G genotype (OR=4.387). No interaction between environmental factors was found that contributing to SLE in this study. CONCLUSION: Many environmental factors were related to SLE, and there was an interaction between -2518MCP-1G/G genotype and eating irritable food.

Adult↗