Biomedical subjects

Weimin Li

Publications and source records attributed to Weimin Li.

23 records · Page 2Linked to original sources

PubMed2002

Influence of Valsartan on myocardial apoptosis in spontaneously hypertensive rats.

OBJECTIVE: To explore the pathogenic changes of myocardial apoptosis in heart hypertrophy during hypertension and evaluate the anti-apoptosis effect of Valsartan. METHODS: Thirty spontaneously hypertensive rats (SHRs) were divided into two groups: 15 treated with Valsartan (20 mg x kg(-1) x d(-1)) (SHR + Valsartan group), the others with placebo (SHR + placebo group), with 15 normal Wistar rats as control. Systolic blood pressure was measured by the tail-cuff method. The observation period was from 8 to 16 weeks of age. Cardiac apoptosis was evaluated by a Terminal Deoxynucleotidyl Transferase-Mediated dUTP-biotin Nick End Labeling (TUNEL) assay. RESULTS: Mean blood pressure values were 127 +/- 2 mm Hg in controls, 163 +/- 6 mm Hg in the SHR + Valsartan group and 193 +/- 7 mm Hg in the SHR + placebo group at 16 weeks of age, whereas the blood pressure in 8-week-old SHR and Wistar rats were 175 +/- 3 mm Hg and 125 +/- 5 mm Hg, respectively. The ratio of the heart weight over body weight declined in Wistar (3.07 +/- 0.03 mg/g) and SHR + Valsartan groups (3.22 +/- 0.19 mg/g) compared with the SHR + placebo group (4.02 +/- 0.31 mg/g) (P < 0.05). The density of TUNEL-positive cells in Wistar and SHR +/- Valsartan groups was 23.3 +/- 3.3 nuclei/HPF and 35.0 +/- 1.3 nuclei/HPF, both of which were significantly less than that of the SHR + placebo group (116.7 +/- 11.3 nuclei/HPF). CONCLUSIONS: In response to chronic pressure overload, cardiomyocyte-specific apoptosis contributes to the transition from compensatory hypertrophy to decompensation. Apoptosis may be effectively inhibited by Valsartan in the early stage of hypertension.

Animals↗

PubMed2002

[IS6110-restriction fragment length polymorphism based DNA fingerprinting in molecular epidemiology of tuberculosis].

OBJECTIVE: To identify the IS6110-restriction fragment length polymorphism (RFLP) DNA fingerprinting patterns of some clinical isolates of Mycobacterium tuberculosis (MTB) isolated from Ningxia, Beijing and Shanghai in recent years, and to observe their epidemiological characteristics. METHODS: Chromosomal DNA of MTB was digested with endonuclease PvuII, then electrophoresed on agarose gel plate and transferred capillarilly to a nylon filter and hybridized with 245 bp fragment of IS6110 which labeled using random primer fluorescein labeling kit. The RFLP patterns of Southern hybridization were inspected autofluorographically and the chromosomal DNAs of MTB were thereby typed. RESULTS: Most of 103 isolates of MTB shared 8 approximately 21 copies. Some of them were clustered. Strains isolated from Ningxia and Beijing had similar DNA fingerprinting patterns. One zero copy strain and one single copy strain were found among isolates from Shanghai. CONCLUSIONS: IS6110-RFLP based typing is feasible for MTB molecular epidemiological study in China. Most of isolates of MTB show analyzable patterns. Isolates of MTB from Ningxia and Beijing have close genomic relation.

China↗

PubMed2002

[Analysis of complications after cardiac valve replacement: report of 702 patients].

OBJECTIVE: To define the determinants of perioperative death and complications after cardiac valve replacement in 702 patients. METHODS: Clinical data of the patients after cardiac valve replacement were analyzed retrospectively. RESULTS: Perioperative mortality and morbidity correlated significantly with some of the perioperative variables, such as higher NYHA functional class (III or IV), large left ventricular end-diastolic diameter (>/= 70 mm), C/T >/= 0.70, prolonged aortic cross-clamping time and cardiopulmonary bypass time, unsatisfactory myocardial protection. CONCLUSIONS: Perioperative mortality and morbidity correlate significantly with some of perioperative variables, such as higher NYHA functional class, unsatisfactory myocardial protection, inappropriate surgical procedure, improper therapy of some complications after cardiac valve replacement. To avoid the occurrence of these independent predictors or to correct them timely might effectively decrease the perioperative mortality and morbidity after cardiac valve replacement.

Adolescent↗

PubMed2002

Chronic treatment of enbrel in rats with isoproterenol-induced congestive heart failure limits left ventricular dysfunction and remodeling.

OBJECTIVE: To investigate the effect of chronic treatment of enbrel (EB), a TNF-alpha antagonist, in a well defined congestive heart failure (CHF) rat model and test the hypothesis that chronic treatment of EB in CHF rats may limit the progression of Left ventricular (LV) dysfunction and structure remodeling and decrease cardiac IL-1beta levels. METHODS: We measured cardiac conformation, contractile performance and cytokines level in 8 age-matched normal adult rats (control group) and 8 rats with isoproterenol (ISO)-induced Heart failure (ISO group) and 8 rats with ISO-induced lesion but received EB treatment (EB group). RESULTS: LV end diastolic diameter and LV end systolic diameter in EB group were significantly less and LV fractional shortening was significantly larger than ISO group (9.2 +/- 0.3 mm vs 9.5 +/- 0.2 mm, 5.8 +/- 0.5 mm vs 6.5 +/- 0.3 mm, 0.37 +/- 0.03 vs 0.31 +/- 0.02, P < 0.05, P < 0.01, P < 0.01 respectively , but there was no significant difference of LV posterior wall thickness at end diastole between the two groups; LV end systolic pressure (P(ES)) dp/dt(max) in EB group were significantly greater than ISO group (104.8 +/- 4.6 mm Hg vs 98.4 +/- 4.9 mm Hg, 8395 +/- 940 mm Hg/s vs 6898 +/- 612 mm Hg, P < 0.05 P < 0.01 respectively), and LV end diastolic pressure (P(ED)) dp/dt(min), time constant of LV relaxation were significantly lower than ISO group (3.8 +/- 0.6 mm Hg vs 7.1 +/- 0.8 mm Hg, -5963 +/- 475 mm Hg/s vs-5030 +/- 316 mm Hg/s,15.4 +/- 0.8 ms vs 21.3 +/- 1.4 ms, P < 0.01, respectively . Although cardiac contractile performance in the EB group was greatly improved, there still was a big gap when compared with the control group. The ratio of LV weight to body weight in the EB group was significantly higher than control group 2.82 +/- 0.07 mg/g vs 2.28 +/- 0.08 mg/g, P < 0.01 but there was no significant difference when compared with the ISO group. There was no significant difference between the serum level of TNF-alpha in EB group and ISO group the it could not be detected in control group. TNF-alpha levels in LV of EB group was significantly higher than control group, 757.6 +/- 46.8 pg/g vs 367.5 +/- 22.7 pg/g, P < 0.01 but there was no significant difference when compared with ISO group. The IL-1beta level in LV of EB group was significantly lower than ISO group 356.2 +/- 28.5 pg/g vs 518.4 +/- 32.5 pg/g, P < 0.05 and it could not be detected in control group. The serum level of IL-1beta could not be detected in any rats. CONCLUSION: EB administered as soon as possible when ISO induced myocardial necrosis occurs can greatly improve cardiac contraction, and the improvement may be partly due to a decrease in the IL-1beta level in LV, besides the direct blocking effect of EB on TNF-alpha. EB can alleviate cardiac remodeling by its effect on LVEDD.

Animals↗

PubMedDate not supplied

Venous hypertension induces increased platelet reactivity and accumulation in patients with chronic venous insufficiency.

The objective of this study was to determine whether there are changes in platelet activation and rheology in patients with chronic venous insufficiency (CVI) and what their impact is on this disease. Anticoagulated peripheral venous blood collected from 21 patients with CVI and 13 normal control subjects in different bodily positions was incubated either with 0.5 mumol/L adenosine diphosphate (ADP) or without agonist and analyzed by whole blood flow cytometry. Soluble P-selectin was analyzed in obtained sera by enzyme-linked immunosorbent assay. Platelet count was determined by a whole blood analyzer. Circulating platelets were more reactive to stimulation with 0.5 mumol/L ADP in patients with CVI compared with control subjects. There was no statistically significant change in platelet activation without ADP and the level of soluble P-selectin as a function of posture. Under simulated venous hypertension, platelet accumulation was observed in patients with CVI. Patients with CVI had increased platelet reactivity and accumulation during orthostasis, suggesting this might be a contributory factor to CVI pathogenesis.

Adenosine Diphosphate↗