Chinese medical sciences journal = Chung-kuo i hsueh k'o hsueh tsa chih最新文献

Many studies on oxidative stress, insulin resistance, and antioxidant treatment have shown that increased oxidative stress may accelerate the development of diabetic complications through the excessive glucose and free fatty acids metabolism in diabetic and insulin-resistant states. Many pathogenic mechanisms such as insulin receptor substrate phosphorylation are involved in insulin resistance induced by oxidative stress. And antioxidant treatments can show benefits in animal models of diabetes mellitus and insulin resistance. However, negative evidence from large clinical trials suggests that new and more powerful antioxidants need to be studied to demonstrate whether antioxidants can be effective in treating diabetic complications. Furthermore, it appears that oxidative stress is only one of the factors contributing to diabetic complications. Thus, antioxidant treatment would most likely be more effective if it were coupled with other treatments for diabetic complications.

Objective: To quantitatively evaluate the metabolic changes of benign prostatic hyperplasia (BPH) and prostate cancer in the transitional zone using magnetic resonance spectroscopic imaging (MRSI), and to analyze the characteristics and differences of the spectra in this zonal area.

Methods: Eighteen patients with prostate cancer in the transitional zone underwent magnetic resonance imaging (MRI)/MRSI examinations. The (Choline + Creatine)/Citrate (CC/Ci) ratio and the Choline/Creatine (Cho/Cr) ratio were evaluated in each voxel with cancer or BPH confirmed by pathological results. Discriminant analysis was used to determine the power of the two ratios in differentiation between cancer and BPH.

Results: The CC/Ci ratio and Cho/Cr ratio for cancer voxels were significantly higher than those in the voxels with BPH in the transitional zone (CC/Ci: 2.36 +/- 1.31 vs. 0.85 +/- 0.29, P < 0.01; Cho/Cr: 4.14 +/- 1.79 vs. 1.26 +/- 0.45, P < 0.01). As for the discriminant function with the CC/Ci ratio and the Cho/Cr ratio, the specificity, sensitivity, and accuracy were 98.6%, 85.7%, 92.9% respectively for the differentiation between cancer and BPH.

Conclusions: The prostate cancer is characterized by higher CC/Ci ratio and Cho/Cr ratio compared to BPH in the transitional zone. Both CC/Ci ratio and Cho/Cr ratio have high specificity, sensitivity, and accuracy in their discriminative power between cancer and BPH in this zonal area.

Objective: To assess the sensitivity, specificity, and feasibility of 4 recombinant Treponema pallidum antigen-based rapid tests in the diagnosis of syphilis.

Methods: A total of 970 outpatients were selected from the Sexually Transmitted Diseases Centre of Peking Union Medical College Hospital. Venous blood was collected and serum was extracted. T. pallidum antibodies in whole blood, anticoagulant whole blood, and serum were detected using 4 recombinant T. pallidum antigen-based rapid tests. T. pallidum haemagglutination test (TPHA) was considered as the gold standard for the detection of T. pallidum specific antibodies in serum. The sensitivities and specificities of four methods were analyzed.

Results: The sensitivities and specificities of Abbott Determine Syphilis TP test, SD-BIOLINE Syphilis 3.0 test, VISITECT-SYPHILIS test, and Syphicheck-WB test for serum specimens were 100% and 98.9%, 95.7% and 98.0%, 94.6% and 98.2%, 68.1% and 98.9%; for whole blood were 74.1% and 99.5%, 87.9% and 99.4%, 73.2% and 99.7%, 64.7% and 99.7%. The observed sensitivities of the 4 rapid diagnosis tests were not significantly different with TPHA (P > 0.05).

Conclusions: The 4 rapid tests show good performance and characteristics in the diagnosis of syphilis. Furthermore, they are more sensitive for serum specimens than whole blood.

Objective: To determine the risk of noncardiac surgery in patients with hypertrophic cardiomyopathy.

Methods: We reviewed the medical records of all patients who were diagnosed as hypertrophic cardiomyopathy at Peking Union Medical College Hospital from January 1998 to August 2006 and identified 24 patients who subsequently underwent noncardiac surgery.

Results: There were no intraoperative cardiac events. Postoperative cardiac events were identified in 3 patients including 1 death due to acute myocardial infarction and 2 episodes of transient hypotension.

Conclusions: The risk of anesthesia and noncardiac surgery is low in patients with hypertrophic cardiomyopathy. During the perioperative period, beta-blockers and/or calcium channel blockers should be given; vasodilator and inotropic agents should be avoided due to the side effects on hemodynamics.

Objective: To investigate the levels of cardiovascular disease risk factors and their relations to clinical phenotype associated with coronary artery disease (CAD).

Methods: The subjects were recruited from five independent cardiovascular centers. Coronary angiography was employed to define the CAD with stenosis in each major vessel > or = 70% and control with stenosis < 10% in every lesion. The classic risk factors including family history, body mass index, smoking habits, hypertension, diabetes mellitus, and serum lipid levels were surveyed according to established criteria. Associations between risk levels and clinical phenotypes were assessed by case control and correlation analysis.

Results: A total of 762 individuals were collected, including 481 men and 281 women, aged from 17 to 81 (mean 60 +/- 10) years. The patients with CAD accounted for 55.5% of all participants, and controls 44.5%, respectively. Compared with the pattern in published data, our study showed that mean serum high density lipoprotein cholesterol (HDL-C) level was significantly lower (P < 0.001) and triglycerides was significantly higher (P < 0.001), while total cholesterol (TC) and low density lipoprotein cholesterol levels were comparative (both P > 0.05). The prevalence of low HDL-C (< 40 g/L) and hypertriglyceridemia (> 150 g/L) were 27.2% and 41.4%, respectively. Mean serum levels of HDL-C and apolipoprotein A1 were significantly higher in female subjects than in male (P < 0.001). Lower HDL-C functioned as an independent risk factor for CAD only in men (RR = 2.8, 95% CI: 1.5-4. 2, P < 0.001), yet increased non-HDL cholesterol combined with diabetes mellitus and obesity seemed to play a key role in the development of CAD in women. Similarity in risk association with CAD was found for hypertension and TC/HDL ratio in male and female subjects, while family history had no relationship with the presence of CAD.

Conclusion: It is remarkable that emphasis of intervention in future should be given on the prevalent low serum HDL-C and its strong risk correlation with the presence of CAD in male subjects of Chinese Han population.

Objective: To explore the scan technique and image quality of coronary angiography with dual source computed tomography (CT) without oral metoprolol preparation.

Methods: Plain and enhanced dual source CT coronary angiography without oral metoprolol preparation was prospectively performed in 600 patients. Calcium scoring with plain scan images as well as multi-planar reconstruction (MPR), maximum intensity projection (MIP), and volume rendering technique (VRT) reconstruction with enhanced scan images were performed in all cases. The scan technique and post-reconstruction experience was summarized. The image quality was classified as 1 to 4 points, and coronary segments classified according to the American Heart Association standards were evaluated.

Results: The average calcium score of the 600 cases was 213.6 +/- 298.7 (0-3,216.5). The average heart rate of the enhanced scan was 82.1 +/- 16.2 (47-139) bpm. The post-reconstruction methods with which coronary segments could be shown as best as possible consisted of single phase reconstruction method, two or more phases supplemented method, and electrocardiogram editing method. Altogether 8,457 coronary segments were evaluated, among which 97.2% were evaluated as point 1, 1.7% point 2, 0.5% point 3, and 0.6% point 4. The coronary segments in 261 cases were completely normal, while 360 segments were diagnosed with < 50% stenosis and 625 segments with > or = 50% stenosis.

Conclusions: Excellent coronary artery image can be obtained with dual source CT in patients with any heart rate without oral metoprolol preparation. Heart rate is not a major source of the artifact, coronary segments can be well shown with single or multiple-phase reconstruction method.

Objective: To investigate vascular endothelial growth factor (VEGF) and its signaling pathway spontaneous response in type 2 diabetes mellitus (T2DM) mice to surgery-induced hind-limb ischemia.

Methods: Sixty mice were randomly divided into two groups, one was fed with normal chow as control, and another was fed with high fat diet to induce T2DM. Fourteen weeks later, mice were surgically induced to hind-limb ischemia. Blood flow restoration was monitored with laser Doppler perfusion imaging. Tibialis anterior muscle was collected after 3 days of hind-limb ischemia. VEGF mRNA and protein expressions were analyzed using real-time PCR and ELISA; expressions of VEGF downstream signal molecules and receptors were analyzed using Western blotting and RT-PCR, respectively.

Results: Perfusion recovery 10, 20, 30 days after ischemia was significantly attenuated in T2DM compared with control group (P < 0.05). T2DM impaired VEGF signaling pathway although VEGF levels increased in T2DM group. After ischemia, T2DM group had a comparable increase in VEGF expression compared with control group, but still had an impaired VEGF signaling pathway.

Conclusion: VEGF signaling pathway is abnormal in T2DM mice, although VEGF had a response to the ischemic stimulation.

Objective: To explore the infarct sites in patients with inferior wall acute myocardial infarction (AMI) concomitant with ST segment elevation in leads V1-V3 and leads V3R-V5R.

Methods: Five patients diagnosed as inferior, right ventricular, and anteroseptal walls AMI at admission were enrolled. Electrocardiographic data and results of isotope 99mTc-methoxyisobutylisonitrile (MIBI) myocardial perfusion imaging and coronary angiography (CAG) were analyzed.

Results: Electrocardiogram showed that ST segment significantly elevated in standard leads II, III, aVF, and leads V1-V3, V3R-V5R in all five patients. The magnitude of ST segment elevation was maximal in lead V1 and decreased gradually from lead V1 to V3 and from lead V1 to V3R-V5R. There was isotope 99mTc-MIBI myocardial perfusion imaging defect in inferior and basal inferior-septal walls. CAG showed that right coronary artery was infarct-related artery.

Conclusions: The diagnostic criteria for basal inferior-septal wall AMI can be formulated as follows: (1) ST segment elevates > or = 2 mm in lead V1 in the clinical setting of inferior wall AMI; (2) the magnitude of ST segment elevation is the tallest in lead V1 and decreases gradually from lead V1 to V3 and from lead V1 to V3R-V5R. With two conditions above, the basal inferior-septal wall AMI should be diagnosed.

Objective: To investigate the role of transforming growth factor-beta1 (TGF-beta1)/Smad4 pathway in development of renal fibrosis in streptozotocin (STZ)-induced diabetic nephropathy (DN) rats and explore its possible mechanism.

Methods: Male Wistar rats weighing 180-220 g were divided into 5 groups: group A (normal control), group B [diabetes mellitus (DM) 2 weeks], group C (DM 4 weeks), group D (DM 8 weeks), and group E (DM 16 weeks). Except for the normal control group, other groups were induced DM by single injection of STZ (55 mg/kg) respectively. Blood glucose level, serum creatinine, and 24-hour urine protein were examined. Expressions of TGF-beta1 and Smad4 protein and mRNA in kidney were detected using immunohistochemical technique, Western blot, and real-time PCR. mRNA expressions of stromelysin-1 (MMP-3), tissue inhibitor of metalloproteinase-1 (TIMP-1), and collagen In in kidney were also detected by real-time PCR.

Results: The levels of blood glucose, serum creatinine, and 24-hour urine protein in rats of group B, C, D, and E were higher than those of the control group. With the progression of renal fibrosis, the expressions of TGF-beta1 and Smad4 protein and mRNA in kidney of diabetic rats elevated. In addition, the renal MMP-3 mRNA expression diminished in diabetic rats, while TIMP-1 and collagen III mRNA increased.

Conclusions: In STZ-induced diabetic rats, the TGF-beta1/Smad4 appears to play an important role in renal fibrosis of DN. The increased expression of TGF-beta1 and Smad4 might result in the transcriptional regulation of downstream target genes of TGF-beta1/Smad4 pathway, which contributes to the progression of renal fibrosis in diabetic rats.

Objective: To investigate the feasibility and effectiveness of radiofrequency catheter ablation (RFCA) to treat per-manent atrial fibrillation (AF) under the guidance of Carto-Merge technique.

Methods: Fifteen male patients with permanent AF underwent RFCA under the guidance of Carto-Merge technique. The mean age was 54.00 +/- 10.44 years, and duration of AF was 23.66 +/- 14.93 months. Cardiac magnetic resonance angiography (MRA) was performed to obtain pre-procedural three-dimensional (3D) images on the anatomy of left atrium (LA) and pulmonary veins (PVs) before RFCA procedure. Then the electroanatomical map was integrated with 3D images of MRA to form Carto-Merge map that guided step-by-step ablation strategy of permanent AF. Circumferential PV ablation was performed first until complete PVs electric isolation confirmed by Lasso catheter. If AF was not terminated, lesion lines on roof of LA, mitral isthmus, and tricuspid isthmus were produced.

Results: The episodes of AF were terminated during RFCA in 2 patients, by direct current cardioversion in the remaining 13 patients. Transient AF occurred in 2 patients after ablation on 1st day and 1st week respectively, AF terminated spontaneously not long after taking metoprolol. One patient developed persistent atrial flutter (AFL) in 2 months after procedure and AFL was eliminated by the second ablation. Persistent AF recurred on 1st day, 1st and 5th week respectively in 3 patients, and did not terminate after 3 months even though amiodarone was given. The remaining 12 patients were all free of AF during 2-11 months of follow-up. The recent success rate for RFCA of permanent AF was 80%.

Conclusions: Carto-Merge technique can effectively guide RFCA of permanent AF. When combined with single Lasso mapping, it can simplify the mapping, lower expenses, and enhance the success rate of RFCA of permanent AF.