Yu Ruan

Zhejiang University, Hangzhou, Zhejiang Sheng, China

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Publications (5)2.06 Total impact

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    ABSTRACT: To investigate effects of glucose excursion on the oxidative/antioxidative system in subjects with different types of glucose regulation. A total of 30 individuals with normal glucose regulation (NGR), 27 subjects with impaired glucose regulation (IGR) and 27 subjects with newly diagnosed type 2 diabetes mellitus (T2DM) were selected and recruited for 3 days' continuous glucose monitor system (CGMS) assessment. The data from CGMS was used to calculate the mean amplitude of glycemic excursion (MAGE), mean blood glucose (MBG) and its standard deviation (SDBG), area under the ROC curve when the blood glucose >5.6 mmol/L within 24 h (AUC 5.6), mean of daily differences (MODD), and mean postprandial glucose excursion (MPPGE). In all groups, the content or activity of malondialdehyde (MDA), total antioxidation capacity (TAOC) and glutathione peroxidase (GSH-Px) were detected. Glucose excursion parameters of subjects with T2DM or IGR were higher than those of NGR subjects (P<0.05 or 0.01). Moreover, Glucose excursion parameters of T2DM subjects were higher than those of IGR subjects (P<0.05 or 0.01). Subjects with T2DM or IGR had significant higher MDA levels and lower GSH-Px/MDA and TAOC/MDA levels compared to NGR subjects (P<0.01). T2DM subjects had even higher MDA levels and lower GSH-Px/MDA levels than IGR (P<0.05 or 0.01). According to the median of normal population for MAGE, T2DM and IGR subjects were divided into MAGE>2.6mmol/L Group and MAGE ≤ 2.6mmol/L Group. MAGE>2.6mmol/L Group had higher levels of MDA and lower levels of GSH-Px/MDA than MAGE ≤ 2.6mmol/L Group (P<0.05). There was no significant difference between the two groups (P>0.05) in terms of the levels of TAOC/MDA. Pearson correlation analysis showed that MDA was positively correlated with FPG, 2hPG, MAGE, and SBP. GSH-Px/MDA was negatively correlated with MAGE and TC. TAOC/MDA was negatively correlated with FPG. Partial correlation analysis showed that the relationship between MDA and MAGE, GSH-Px/MDA, and MAGE remained significant after adjustments for the other differences among groups. Glucose excursion contributed significantly to promoting lipid peroxidation and decreasing antioxidation capacity than chronic sustained hyperglycemia did in the subjects with different types of glucose regulation.
    Biomedical and Environmental Sciences 02/2011; 24(1):68-73. · 1.15 Impact Factor
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    ABSTRACT: To investigate the clinical features and risk factors of renal damage in the elderly and non-elderly patients with type 2 diabetes mellitus. The data were collected from a survey of 10-year retrospective study of chronic complications of hospitalized type 2 diabetics organized by Chinese Diabetes Society. A total of 1351 patients of type 2 diabetes were selected and divided into an elderly group (>or=60 year) and a non-elderly group (<60 year). The patients were also divided into three groups according to urinary albumin excretion rate (AER): normoalbuminuria group (AER<30 mg/24 h), microalbuminuria group (30<or=AER<300 mg/24 h) and macroalbuminuria group (AER>or=300 mg/24 h). eGFR was estimated by the equation from the MDRD study. Clinical and laboratory parameters of all patients were analyzed. (1) The proportions of renal insufficiency in both normoalbuminuria and microalbuminuria groups of type 2 diabetes in the elderly patients were significantly higher than those in the non-elderly patients (26.7% vs 15.8%, P<0.01; 30.5% vs 21.3%, P<0.05 respectively); (2) in type 2 diabetic patients with renal insufficiency and normoalbuminuria, the diabetes duration (7.7 vs 3.8 years), systolic blood pressure [(146+/-24) mm Hg vs (134+/-23) mm Hg], diastolic blood pressure [(84+/-13) mm Hg vs (80+/-11) mm Hg], proportion of hypertension (37.8% vs 21.1%), diabetic retinopathy (34.1% vs 23.9%), cardiovascular diseases (31.6% vs 11.3%) and cerebrovascular disease (24.4% vs 9.9%) were significantly higher in the elderly group than in the non-elderly group (P<0.05 or 0.01); (3) multiple logistic regression analysis revealed that the duration of diabetes (OR=1.046, P=0.013) and systolic blood pressure (OR=1.014, P=0.002) were independently associated with renal insufficiency in the elderly type 2 diabetic patients with normoalbuminuria, whereas systolic blood pressure (OR=1.042, P=0.000) and 2-hour postprandial blood glucose (OR=1.048, P=0.002) were independent risk factors for renal insufficiency of non-elderly patients. The elderly type 2 diabetic patients are likely to suffer renal insufficiency initially from a lower glomerular filtration rate than the non-elderly patients. Systolic blood pressure is the main risk factor in both elderly and non-elderly type 2 diabetes with normoalbuminuria and a decreased renal function. Controlling blood pressure may delay the decline of renal function.
    Zhonghua yi xue za zhi 04/2010; 90(14):967-71.
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    ABSTRACT: To investigate the prevalence of renal insufficiency and its associated factors in type 2 diabetes mellitus with normoalbuminuria using estimated glomerular filtration rate (eGFR). We retrospectively analyzed 10-year data of chronic complications in type 2 diabetics in-patient from the Chinese Diabetes Society. eGFR was estimated using the equation from Modification of Diet in Renal Disease (MDRD) study. The clinical characteristics as well as associated factors for low eGFR were analyzed among the normoalbuminuric type 2 diabetic patients. A total of 1351 type 2 diabetic patients were included, 755 patients with normoalbuminuria, 466 patients with microalbuminuria and 130 patients with macroalbuminuria respectively. Among the patients, 310 (22.9%) had low eGFR (GFR < 60 mlxmin(-1) x 1.73 m(-2)), 19.7% (149/755) in the patients with normoalbuminuria, 21.9% (102/466) in microalbuminuria and 45.4% (59/130) in macroalbuminuria. Patients with normoalbuminuria and low eGFR suffered more chronic complications than those with normoalbuminuria and normal eGFR, mainly retinopathy, cerebrovascular diseases and sensory neuropathy. Stepwise logistic regression analysis revealed that age (OR = 1.042, P < 0.001), diabetic duration (OR = 1.038, P = 0.045), systolic blood pressure (OR = 1.017, P < 0.001) were independently associated with renal impairment among the patients with normoalbuminuria. Body mass index (OR = 0.868, P < 0.001) and HbA1c (OR = 0.898, P = 0.021) were also related with renal insufficiency. A considerable proportion in type 2 diabetic patients without albuminuria may exist renal impairment, and eGFR estimation could benefit the evaluation of renal function in such patients.
    Zhonghua nei ke za zhi [Chinese journal of internal medicine] 01/2010; 49(1):24-7.
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    ABSTRACT: To investigate the expression of alpha smooth muscle actin (alphaSMA), a marker of myofibroblast in kidney of diabetic rats and its role in pathogenesis of diabetic nephropathy. Diabetic disease model was made on 24 Sprague-Dauley (SD) rats by an single intraperitoneal injection of streptozotocin (70 mg/kg) and 24 health SD rats served as controls. Six diabetic rats and six control rats were sacrificed at 1, 2, 4, 8 weeks after injection of streptozotocin. At each time-point, the renal morphological changes were examined by histopathology. alpha SMA and collagen-IV (C-IV) expressions were studied by immunohistochemistry (SABC). The content of alpha SMA in renal cortex was detected by enzyme-linked immunosorbent assay(ELISA). At all time-points, renal content of alpha SMA increased in diabetic rats. Compared with controls, diabetic rats had a steady increased accumulation of C-IV. Expression of C-IV was positively correlated with that of alpha SMA. At early stage of diabetes,increased alpha SMA in kidney suggests the formation of myofibroblast, which may be involved in accumulation of C-IV and contributed to diabetic nephropathy.
    Zhejiang da xue xue bao. Yi xue ban = Journal of Zhejiang University. Medical sciences 04/2005; 34(2):152-6.
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    ABSTRACT: The changes in matrix metalloproteinase-2 (MMP-2) and matrix metalloproteinase-9 (MMP-9) expressions were examined in the kidneys of diabetic rats to investigate the degradative pathway of collagen type IV (C-IV) and the protective effects of pioglitazone on an experimental model of diabetic nephropathy. In 54 SD rats used in our study, 18 served as normal controls. Diabetes mellitus was induced in 36 age- and weight-matched rats by intraperitoneal injection of streptozotocin (70 mg/kg); 18 of the diabetic rats were allocated at random to receive pioglitazone [20 mg.kg(-1).d(-1)] in their drinking water and 18 served as diabetic controls. Rats were killed after 2, 4, or 8 weeks of treatment. Kidneys were examined pathomorphologically and the expressions of MMP-2, MMP-9, and C-IV were analyzed by immunohistochemistry, and the results were quantified by image analysis techniques. Diabetes mellitus was associated with a decrease in the expression of MMP-2 in the glomeruli (P < 0.05, vs control). By contrast, MMP-2 expression in the interstitium increased, but not significantly (P > 0.05, vs control). The expression of MMP-9 did not show any change when comparing the three groups (P > 0.05, vs control). STZ-diabetic rats were also associated with an increase in the expression of C-IV in the glomeruli and the interstitium (P < 0.05, vs control). All diabetes-associated changes in MMP-2 expression were attenuated by pioglitazone treatment in association with reduced C-IV accumulation. These results indicate that a decrease in MMP-2 expression in the glomeruli of diabetic rats may lead to impairment of C-IV degradation and contribute to the matrix accumulation in diabetic nephropathy. Pioglitazone treatment, which can attenuate the decrease of glomerular MMP-2 and the increase of C-IV degradation, has curative effects on diabetic nephropathy.
    Chinese medical journal 08/2004; 117(7):1040-4. · 0.90 Impact Factor