It has been recently demonstrated that the Mg(2+)-dependent 3'-processing activity of purified human immunodeficiency virus type-1 (HIV-1) integrase is stimulated by the addition of exogenous Zn2+ [Lee, S. P., & Han, M. K. (1996) Biochemistry 35, 3837-3844]. This activation was hypothesized to result from integrase self-association. In this report, we examine the Zn2+ content of purified HIV-1 integrase by atomic absorption spectroscopy and by application of a thiol modification reagent, p-(hydroxymercuri)benzenesulfonate, with a metallochromic indicator, 4-(2-pyridylazo)resorcinol. We find that the Zn2+ content of HIV-1 integrase varies from 0.1 to 0.92 equiv of Zn2+ per monomer depending on the conditions of protein purification. In vitro activity assays, time-resolved fluorescence emission anisotropy, and gel filtration chromatographic analyses all indicate that EDTA yields an apoprotein which is predominantly monomeric and less active with Mg2+. Further, sedimentation equilibrium studies reveal that reconstitution of the apoprotein with Zn2+ results in a monomer-tetramer-octamer transition. These results suggest that Zn2+ promotes a conformation with enhanced oligomerization and thereby stimulates Mg(2+)-dependent 3'-processing. This may also imply that multimers larger than dimers (tetramers and possibly octamers) are required for in vitro activity of integrase in the presence of Zn2+ and Mg2+. It should be noted, however, that the content of Zn2+ did not significantly affect the 3'-processing and strand transfer reactions with Mn2+ in vitro.

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Background: Safe and effective therapeutic management of refractory coronary artery disease (CAD) in heart patients is critical to enhance cardiovascular function and improve quality of life. Current therapies for refractory CAD are inadequate in ameliorating angina and promoting revascularization of ischemic myocardium. Hypothesis: Cardiac shock wave therapy (CSWT) is a safe and effective noninvasive intervention in the management of patients with refractory CAD. Methods: The study enrolled 9 male patients age 50 to 70 years (5.11 ± 5.46 years) with a diagnosis of CAD and stent implantation (3.00 ± 2.24 stents). CSWT was carried out for 3 months at 3 intervals during the first week of each month (first, third, and fifth day), for a total of 9 therapies per patient. Dobutamine stress echocardiography and radionuclide angiography identified the myocardial ischemic segments. The effects of CSWT on myocardial perfusion and systolic function were examined. Other outcome measures included myocardial injury enzyme markers, angina scale, nitroglycerin dosage, and cardiopulmonary fitness assessments. Results: Improved myocardial blood flow and regional systolic function (stress peak systolic strain rate −1.10 to −1.60 s −1 , P = 0.002) were detected in patients following CSWT. Reductions in creatine kinase (87.89 ± 36.69 to 86.22 ± 35.96 IU/L, P = 0.046), creatine kinase MB (10.89 ± 5.73 to 10.11 ± 5.93 IU/L, P = 0.008), aspartate transaminase (interquartile range [IQR], 28.00 to 27.00 IU/L, P = 0.034) were also found. Angina (Canadian Cardiovascular Society scale IQR 3.0 to 2.0, P = 0.035) and nitroglycerin dose reduction (IQR 3.0 to 1.0 times/wk, P = 0.038) were reported.Conclusions: This study is a preliminary assessment of CSWT in patients with refractory CAD. We report that CSWT is a noninvasive, effective, and safe intervention in the treatment of refractory CAD.

BackgroundPeroxisome proliferator-activated receptor γ (PPARγ) is a ligand-activated transcription factor, which regulates gene expression of the key proteins involved in lipid metabolism, vascular inflammation, and proliferation. PPARγ may contribute to attenuating atherogenesis and postangioplasty restenosis. PPARγ C161→T substitution is associated with a reduced risk of coronary artery disease (CAD). Whether or not the gene substitution alters the risk of CAD in type 2 diabetes mellitus (T2DM) patients remains unclear.MethodsA total of 556 unrelated subjects from a Chinese Han population, including 89 healthy subjects, 78 CAD patients, 86 T2DM patients, and 303 CAD combined with T2DM patients, were recruited to enroll in this study. PPARγC161→T gene polymorphism was determined by polymerase chain reaction and restriction fragment length polymorphisms. Plasma levels of lipoproteins, apolipoproteins, glucose, and insulin were measured by ELISA or radioimmunoassay (RIA). The coronary artery lesions were evaluated by coronary angiography.ResultsThe frequency of the 161T allele in CAD, T2DM, and CAD combined with T2DM patients was similar to that observed in the healthy control group. However, in CAD combined with T2DM patients, the group with angiographically documented moderate stenoses had a higher frequency of the 161T allele in comparison to the group with severe stenoses (P < 0.05). Moreover, in CAD with T2DM patients, the triglyceride levels and apoB in CC homozygote carriers were significantly higher than those in "T" allele carriers.ConclusionsPPARγC161→T genotypes weren't significantly associated with the risk of CAD, but were markedly correlated with severity of disease vessels in patients with CAD and T2DM. Furthermore, PPARγC161→T substitution was associated with an altered adipose, but not glucose metabolism. These results indicate that the PPARγ C161→T polymorphism may reduce the risk of severe atherogenesis by modulation of adipose metabolism, especially triglycerides and apoB, in Chinese patients with CAD and T2DM.

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BackgroundThe complications of hypertension cause severe health problems in rural areas in China. We (i) screened the major factors inducing hypertensive complications and provided intervention measures; and (ii) verified the efficacy of the New Rural Cooperative Medical Scheme (NRCMS; a medical insurance scheme for rural residents) for hypertension management.MethodsA survey was conducted in the villages of Yunnan (an underdeveloped province in southwest China). The NRCMS was initiated there in 2005. Data were collected through questionnaires, physical examination, electrocardiography, as well as blood and urine tests. To detect factors inducing hypertension complications, a generalized estimating equations model was developed. Multivariable logistic regression was used to analyze influencing factors for hypertension control.ResultsPoor management of hypertension was observed in women. Being female, old, poorly educated, a smoker, ignorant of the dangerousness of hypertension, and having uncontrolled hypertension made patients more prone to hypertension complications. Combination therapy with ≥2 drugs helped control hypertension, but most rural patients disliked multidrug therapy because they considered it to be expensive and inconvenient. The NRCMS contributed little to reduce the prevalence of complications and improve control of hypertension.ConclusionsThe present study suggested that the NRCMS needs to be reformed to concentrate on early intervention in hypertension and to concentrate on women. To increase hypertension control in rural areas in China, compound products containing effective and inexpensive drugs (and not multidrug therapy) are needed.

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