Biomedical subjects

Yi Ma

Publications and source records attributed to Yi Ma.

40 records · Page 3Linked to original sources

PubMed2002

[Relationship between HLA-DQA1, -DQB1 genes polymorphism and susceptilibity to bronchial asthma among Northern Hans].

OBJECTIVE: To investigate the relationship between human leukocyte antigen (HLA)- DQA1, -DQB1 genes polymorphism and susceptibility to bronchial asthma among the Hans in the northern China. METHOD: Sequence-specific primer polymerase chain reaction was used to gene frequencies of HLA-DQA1 and HLA-DQB1 genes among 125 unrelated asthmatics, 12 of which being probands of asthmatic pedigrees, and 96 healthy controls, all of Han nationality and living in Beijing or nearby areas for a long time. Radioimmunosorbent test was used to examine the serum IgE and TigE. The ventilatory function was test among the asthmatics. RESULTS: The frequencies of HLA-DQA1 0104 and HLA-DQB1 0201 were 0.204 and 0.284, significantly higher than those in the healthy controls (0.089 and 0.096 respectively, both P < 0.01). Conversely, the frequencies of HLA-DQA10301 and HLA DQB101301 in the asthmatics were 0.148 and 0.20, significantly lower than those in the controls (0.25 and 0.282 respectively, P < 0.01 and < 0.05). The correlation coefficients between HLA-DQA1 * 0104 and atopy, HLA-DQB1 * 0201 and atopy, and HLA-DQA1 * 0301 and atopy were 0.813 (P < 0.01), 0.289 (P < 0.01), and -0.168 (P < 0.05) respectively. Multi-variate logistic regression asthma. CONCLUSIONS: The alleles HLA-DQA1 * 0104 and HLA-DQB1 * 0201 are correlated with the susceptibility to asthma among Northern of Han nationality. HLA-DQA1 * 0104 is an independent risk factor of onset of asthma. The alleles HLA-DQA1 * 0301 and HLA-DQB10301 are correlated with resistance against asthma. HLA-DQ genes are involved in the regulation of human specific immune responses.

Adult↗

PubMed2002

[CT pulmonary functional imaging in emphysema: a correlative study of CT technique and pulmonary function test].

OBJECTIVE: To compare the effectiveness of high resolution CT, CT pulmonary functional imaging, and pulmonary function test (PFT) in the quantitative evaluation of emphysema and obstructive pulmonary disease. METHODS: The study included 37 patients with obstructive ventilatory defect and 20 normal controls. CT and pulmonary function test were performed in all subjects in one week. Correlation between and differences among HRCT visual scoring, parameters of CT pulmonary functional imaging and the result of pulmonary function test were compared. RESULTS: (1) Emphysema was detected by CT in 23 of the 37 patients with obstructive ventilatory defect. (2) HRCT visual scoring was correlated only with D(L)CO% (r = -0.731, P < 0.001) among other pulmonary function parameters. (3) HRCT visual scoring in patients with enrphysema was correlated with pixel indices (PI) at full inspiration and expiration. Visual scoring showed the best correlation with PI(-910in) (r = 0.506, P < 0.001) and PI(-910ex) (r = 0.610, P < 0.001). (4) The grading of pulmonary function based on PI(-910in) and PI(-910ex) showed no difference from the grading by pulmonary function tests (chi(2) = 0.527, P = 0.913; chi(2) = 3.645, P = 0.302). The grading of emphysema based on PI(-910in) accorded with the grading by pulmonary function tests (chi(2) = 2.59, P = 0.459). CONCLUSIONS: HRCT is more sensitive than conventional CT in diagnosing emphysema. However, in terms of slice thickness and radiation dose, it cannot be used in the evaluation of both lungs. CT functional imaging is easily performed, and the results are objective and correlated with the result of HRCT visual scoring and PFTs. It may be, therefore, more useful in diagnosing early emphysema and evaluating lung function.

Adult↗

PubMed2002

[Influence of warm ischemia injury on energy metabolism and survival of liver graft in rats].

OBJECTIVES: To investigate the energy metabolism and post transplantation survival of liver graft under different warm ischemia times (WIT) in rats and determine the maximum limitation of liver graft to warm ischemia. METHODS: According to WIT, the rats were randomized into 7 groups, and WIT were 0, 10, 15, 20, 30, 45, 60 minutes respectively. The indexes of energy metabolism were measured by reversed-phase high performance liquid chromatography (HPLC) and all liver graft specimens were subjected to ultrastructural observation. After orthotopic liver transplantation (OLTx), the recovery of energy metabolism of liver graft after 24, 48 hours and the rats' survival were observed. RESULTS: The levels of adenosine triphosphate (ATP) and energy charge (EC) decreased gradually after different WIT in a time-dependent manner, and especially significant within 30 minutes. The levels of ATP and EC of liver grafts were largely recovered after 24 hours of OLT within 30 minutes of warm ischemia, partially recovered after 48 hours of OLT with 45 minutes of warm ischemia and hardly recovered even after 48 hours of OLT with 60 minutes of warm ischemia. The rat survival time after OLT was not significantly different within 30 minutes of WIT, while the long-term survival was insulted with 45 and 60 minutes of WIT. CONCLUSIONS: The levels of ATP and EC after OLT may be the important criteria to evaluate the quality of liver graft. WIT of liver graft is closely related to both the recovery of hepatic energy metabolism and the liver graft survival.

Adenosine Triphosphate↗

PubMed2002

[Association of polymorphism of human beta 2-adrenergic receptor gene and bronchial asthma].

OBJECTIVE: To investigate whether beta 2-adrenergic receptor gene (beta 2AR) polymorphism at position 16, 27, 164 is in association with asthma susceptibility or asthmatic phenotype (including nocturnal asthma, serum IgE level, bronchial responsiveness, the status of asthmatics). METHODS: By using PCR-RFLP and allelic-specific PCR (ASP), the polymorphism of beta 2AR gene at position 16, 27, 164 in 125 Han origin asthmatics and 96 normal healthy controls with the same ethnic nearby Beijing region were genotyped. All patients had their serum total IgE (TIgE) measured by RAST, pulmonary ventilatory function assessed by FEV1% and FEV1/FVC, bronchial responsiveness challenged by methacholine (if FEV1% > 70%), and brocho-reversibity by inhaling beta 2-agonist. RESULTS: There was higher prevalence of Gly16 homozygous of beta 2AR in asthmatics than that in normal healthy controls (22.4% vs 8.3%, P < 0.05), with odd ratio (OR) 2.918 (95% CI: 1.256-6.781); Also there was higher frequency of Gly16 homozygous of beta 2AR in nocturnal asthmatics than that in nonnocturnal asthmatics (35.3% vs 13.5%, P < 0.01), but Gly16 homozygous of beta 2AR was low an independent risk factor for the pathogenesis of asthma. The dose of methacholine was low in asthmatics carrying Gln27 homozygous beta 2AR than Glu27 homozygous beta 2AR and Gln/Glu27 heterozygous beta 2AR in brocho-challenge test [(0.205 +/- 0.275) vs (2.11 +/- 3.00) vs (1.575 +/- 0.828) mumol, P < 0.05]. CONCLUSIONS: Gly16 homozygous beta 2AR was associated with asthma susceptibility in Chinese patients with Han ethnic nearby Beijing region, and Gly16 homozygous beta 2AR was associated significantly with nocturnal asthma. Glu27 homozygous beta 2AR was related to hyper-bronchial reactivity of asthmatics.

Asthma↗