Construction of type 2 diabetes rat models of lower limb ischemia by feeding with high-fat diet / 中国组织工程研究

BACKGROUND:The method of ligating or resecting rat lower limb femoral or iliac artery has been widely used to make rat models of lower limb ischemia, but there have been no stable and efective methods used to establish diabetic models of chronic atherosclerotic occlusive diseases and to evaluate the ischemic status of hindlimbs of models. OBJECTIVE: To establish type 2 diabetes rat models of lower limb ischemia by feeding with high-fat diet and to evaluate them. METHODS:Twenty rats were randomly and evenly divided into diabetes group (n=10) and control group (n=10). Rats in the diabetes group were fed with high-fat diet for 6 months, and were intraperitonealy injected with streptozotocin (50 mg/kg) to induce diabetes. Rats in the control group were fed with normal diet for 6 months. Rats in these two groups were subjected to ligation of femoral artery to establish right lower limb ischemia models. RESULTS AND CONCLUSION:At the first day of modeling, color Doppler flow imaging and CT angiography showed obviously decreased blood flow suggesting the success of establishing ischemia model. At 7 and14 days after modeling, the blood flow of rats in these two groups showed a gradual recovery as detected by color Doppler flow imaging. At 28 days after modeling, blood flow of rats in the diabetes group was significantly slower than that in the control group (P < 0.05). CT angiography showed that at 28 days after modeling, only a smal amount of compensatory increase in blood flow of the blood vessels at the ligation position of proximal right lower limb femoral artery was seen in the diabetes group, while no obvious blow was observed in the distal part. Histopathologic and immunohistochemical staining showed that at 28 days after modeling, destroyed tissue structure and inflammatory cel infiltration were observed in the ischemic region and capilary density on the affected side was lower than that on the healthy side. The protein expression of vascular endothelial growth factor in the ischemic muscle tissue of rats in the diabetes group was significantly increased compared with that in the control group (P < 0.05). These results show that diabetic rat models of lower limb ischemia can be successfuly established by long term high-fat diet feeding and femoral artery ligation and they can be validated by CT angiography.

Tanshinone attenuates myocardial injury via activating JAK2/STAT1 pathway in a murine model of viral myocarditis / 中华心血管病杂志

<p><b>OBJECTIVE</b>To explore the effects of tanshinone and JAK2/STAT1 signaling pathway related mechanism in CVB3-induced myocarditis in murine.</p><p><b>METHODS</b>A total of 110 inbred male Balb/c mice which were 4 to 6 weeks-old were randomly divided into five groups: normal control (N, n = 10), myocarditis control (C, n = 25), tanshinone group (T, 15 mg · kg⁻¹ · d⁻¹, i.p., n = 25), janus kinase 2 inhibitor AG490 group (A, 10 mg · kg⁻¹ · d⁻¹, i.p., n = 25), T+A group (H, n = 25). Myocarditis was induced by 0.5 ml 10(-9.51) TCID50/ml CVB3 i.p. injection for 10 days in group C, T and H. Myocardial histopathologic changes were observed and phospho-STAT1 expressions were detected by immunohistochemistry and Western blot analysis. The levels of serum cardiac troponin I were detected with chemiluminescence immunoassay.</p><p><b>RESULTS</b>(1) Compared with group C, the histopathologic scores were significantly higher in group A and H (3.35 ± 0.57 and 3.34 ± 0.54 vs. 2.12 ± 0.39, P < 0.01), but lower in group T (1.40 ± 0.34 vs.2.12 ± 0.39, P < 0.01). (2) The expression of p-STAT1 protein was similar in group A and H compared to group N (P > 0.05), but was significantly lower than that in group C (0.017 ± 0.010 and 0.020 ± 0.010 vs. 0.246 ± 0.010, P < 0.01). The expression of p-STAT1 protein was significantly higher in group T than in group C (P < 0.01). (3) The levels of serum cardiac troponin I in group C, A, T and H were significantly higher than in group N ((0.42 ± 0.06), (1.17 ± 0.25), (0.23 ± 0.05) and (1.04 ± 0.19) µg/L vs. (0.02 ± 0.01) µg/L, all P < 0.01). The levels of serum cardiac troponin I were significantly higher in group A and H compared with group C ((1.17 ± 0.25) and (1.04 ± 0.19) µg/L vs. (0.42 ± 0.06) µg/L, P < 0.01), but were significantly lower in group T than in group C ((0.23 ± 0.05) µg/L vs. (0.42 ± 0.06) µg/L, P < 0.01). (4) There was a negative correlation between the expression level of p-STAT1 and the histopathologic scores (y = -4.503 x + 3.371, R² = 0.738, P < 0.01), but a positive correlation between the levels of serum cardiac troponin I and the histopathologic scores (y = 1.935x + 1.165, R² = 0.766, P < 0.01).</p><p><b>CONCLUSION</b>Tanshinone could attenuate myocardial injury via upregulating the JAK2/STAT1 signaling pathway in this murine viral myocarditis model.</p>

Effect of occupational manganese exposure on uric Acid levels in human urine / 生物医学与环境科学（英文）

<p><b>OBJECTIVE</b>To investigate the effect of long-term and low-level occupational Mn exposure on the level of uric acid (UA) in human urine.</p><p><b>METHODS</b>In this study, 65 volunteers were recruited, who were working on welding and foundry work in an plant in Gansu province, China. Additionally, 29 control samples were collected from individuals who did not have any history of excessive Mn exposure. An improved high performance liquid chromatography system equipped with a diode-array detector (HPLC-DAD) method was developed to determine the UA level in human urine. A Spectra AA 220 Atomic Absorption Spectrophotometer (AAS) was used to measure the Mn level in the urine.</p><p><b>RESULTS</b>The analytical method was validated for concentrations ranging from 3.82-45.84 μg/mL with acceptable accuracy, precision, and recovery. Overall, the UA levels of Mn exposure samples were significantly lower than that of control samples (P<0.05).</p><p><b>CONCLUSION</b>The practical method developed here is suitable for both routine monitoring of UA level in human urine and metabolism research. Long-term and low-level occupational Mn exposure may lead to a lower UA level in urine, and UA might be an indicator of the early stage of manganism.</p>

Characteristic of Talldust in Sand-Storm in Northwest Area of China / 环境与健康杂志

Objective To survey free crystalline silica[SiO_2(F)]content,particle size and water-soluble components concentration in the sand-dust storm dust,in order to prevent large-scale non-occupational silicosis(desert lung) prevalence in northwest desert area of China.Methods Atmospheric dust(falldust) were collected in Hetian,Minqin,Zhongwei and Lanzhou city when sand-dust storm befallen and free crystalline silica,particle size ratio and water-soluble components were analyzed according to GB 5748—1985.Results The rate of SiO_2(F) component was over 50%in the original sand,the rate of SiO2(F) component was from 17.36% to 48.09%in the falldust of sand-dust storm,the falldust belongs to crystal dust.The inhaleble particle(particles with amedian diameter of 0.5-10?m) ratio was from 63.3%to 84.1%.The water-soluble components concentration increased as sand-dust storm moving.C1,SO_4~(2-) and NO_3~- content was from 220?g/g,870?g/g and 230?g/g of Hetian to 980?g/g,5 400?g/g and 1 400?g/g of Lanzhou(P

Doppler Echocardiography Assessment of Right Ventricular Filling Dynamics in Essential Hypertension / 中华超声影像学杂志

In order to determine whether alteration in right ventricular filling dynamics Occurs in hypertension and compare the filling dynamics of RV and LV pulsed Doppler echocardiographic studes were performed with sample volumes at the tricuspid and mitral anuli in 51 hypertensive patients and 50 normotensive volunteers.Comparing with the normotensives,in hypertensive patients,RV early filling velocity(46±7 vs 41±6,P<O.05),1/2FF(61±10 vs 55±7,P<O.01)and 1/3FF(52±12 vs 44±8, P<0.01)were lower;ration of A/E(0.8±0.2 vs 1.0±0.4,P<O.05)and AFF(24±9 vs 39±14,P <0.01)were higher.LV filling parameters showed similar changes.RV filling dynamics were closely related to LV filling dynamics in both hypertensive patients(r=0.59～0.87,P<0.01)and normotensive individuals(r=0.65～0.90,P<0.01).However,no correlations were found between filling dynamics and LVM,LV posterior wall thickness.RV anterior thickness,blood pressure. concluded that RV filling dynamics are abnormal in hypertension,independent of LVM or blood pressure,and are closely related tO LV filling dynamics.