Objective To investigate the value of diffusion kurtosis imaging (DKI) in diagnosing early diabetic nephropathy. Methods Twelve pigs were divided into the experimental group (7 pigs) and the control group (5 pigs), used the random number table method. The experimental group was fed with high?fat high?sugar diet,and then repeatedly injected small doses(50 mg/kg) of Streptozotocin (STZ) through the ear vein. Meanwhile,the control group was fed with normal diet and injected with the same dose of citric acid?sodium citrate buffer solution.After the type 2 diabetes was established successfully, T1WI, T2WI and DKI sequence imaging were performed every month for 2 pigs from the experimental group and the control group,respectively.Mean kurtosis(MK), axial kurtosis (K∥), radial kurtosis (K⊥), fractional anisotropy (FA) and mean diffusivity(MD) were measured on the pseudo?color map of the post?processing workstation. fasting blood glucose(GLU),insulin (INS),renal function, urine routines and random albumin creatinine ratio(RACR) were measured before MRI scan. Specimens from bilateral kidneys were taken for pathological examination after MRI scan. The paired t test was used to compare the parameter values of the cortex and medulla. Independent sample t test was used tocompare the parameter values of the experimental group and the control group. Results In the experimental group,the MK, FA values of medulla were 0.66±0.07 and 0.19± 0.04, the MK, FA values of cortex were 0.60±0.06 and 0.16±0.03.In the control group,the MK, FA values of medulla were 0.59±0.03 and 0.20±0.04, the MK, FA values of cortex were 0.53±0.03 and 0.17±0.04.The MK and FA values of medulla were increased compared with the cortex and the difference were statistically significant (P<0.01). The MK, K⊥ values of cortex and medulla were increased in the experimental group compared with the control group and the difference were statistically significant (P<0.05). There was no significant differences in the K∥, FA and MD values between two groups (both cortex and medulla, P>0.05). Conclusion DKI sequencehas certain value in the diagnosis of early diabetic nephropathy, and to some extent reveals the pathological change in early diabetic nephropathy.

Objective:To evaluate the application value of conventional echocardiography and two-dimensional speckle tracking imaging (2D-STI) in assessing the left ventricular systolic and diastolic functions in patients with restrictive cardiomyopathy (RCM).Methods:Fifteen patients confirmed as RCM by cardiac magnetic resonance imaging or pathological biopsy in Fuwei Cardiovascular Hospital of Yunnan Province from September 2017 to June 2020 were selected. According to left ventricular ejection fraction(LVEF), they were divided into LVEF retention group(LVEF≥50%, 8 cases) and LVEF reduction group (LVEF<50%, 7 cases). Meanwhile, 20 healthy volunteers were selected as the control group. Conventional echocardiography and 2D-STI were used to evaluate left ventricular systolic and diastolic function, including left ventricular end-diastolic diameter (LVEDd), LVEF, mitral valve blood flow spectrum peak E/peak A, peak E deceleration time (EDT), tissue Doppler mitral valve ring average early diastolic peak velocity (e′), E/e′ ratio, isovolumetric relaxation time (IVRT), left atrial volume index (LAVI) and speed of tricuspid regurgitation (TVR), tricuspid annular plane systolic excursion (TAPSE), left ventricular longitudinal strain (LS) and circumferential strain (CS). Then the differences and similarities between the two RCM groups and the control group were compared.Results:There was no significant difference of LVEF between LVEF retention group and the control group ( P>0.05), and LVEF in LVEF reduction group was significantly lower than that in control group ( P<0.05). LVEDd in LVEF retention group was significantly smaller than that of LVEF reduction group ( P<0.05), but was not statistically different from the control group ( P>0.05). Values of E/A, E/e′, LAVI and TVR in LVEF retention group and LVEF reduction group were significantly greater than the control group (all P<0.05), and there was no statistically significant difference between the two RCM groups ( P<0.05). Values of e′, EDT, IVRT and TAPSE in LVEF retention group and LVEF reduction group were significantly lower than the control group (all P<0.05), and there was no statistically significant difference between the two RCM groups (all P>0.05). The global LS and LS of AP4, AP3, and AP2 showed significantly different among the 3 groups (all P<0.05). The global and basal, middle, apical segmental CS in LVEF retention group were significantly larger than those in LVEF reduction group (all P<0.05), but they were not significantly different from the control group (all P>0.05). Conclusions:All patients with RCM show left ventricular diastolic dysfunction in conventional echocardiography, and show gradually reduced left ventricular systolic function and left ventricular remodeling. RCM patients with normal LVEF demonstrate decreased myocardial systolic function, and left ventricular global LS could be used as a sensitive indicator to predict myocardial systolic function.

Objective To investigate the distribution characteristics and risk factors of intracranial and extracranial aterial lesions in Chinese patients with ischemic stroke . Methods In this multi‐center study ,2 310 continuously inpatients with ischemic stroke diagnosed in 20 stroke screening and prevention project base hospitals from June 2015 to M ay 2016 were enrolled . Carotid ultrasonography and transcranial color‐coded sonography or transcranial Doppler were performed in all patients to confirm the presence of cerebral artery stenosis or occlusion . According to the distribution of lesions ,the subjects were divided into 2 groups :the simple intracranial artery stenosis group and the simple extracranial artery stenosis group . T he difference of risk factors between the two groups was compared . Results Of the 2 310 patients with ischemic stroke ,1 516 ( 65 .6% ) had simple intracranial artery stenosis and 794 ( 34 .4% ) had simple extracranial artery stenosis . T he incidence of anterior circulation artery stenosis was higher in the group of intracranial artery stenosis than that in the extracranial artery stenosis group ( 68 .1% vs 48 .7% , P ＜0 .001) . Posterior circulation artery stenosis and combined anterior with posterior circulation artery stenosis were more common in patients with extracranial artery stenosis group than those in intracranial artery stenosis group ( 36 .4% vs 22 .1% ,14 .9% vs 9 .8% ;all P ＜0 .001) . Univariate analysis of risk factors for stroke showed that patients with intracranial arterial stenosis had a higher prevelence of hypertension , diabetes ,obesity ,and family history of stroke ,and their systolic blood pressure ,diastolic blood pressure , body mass index ( BM I) ,fasting blood‐glucose ,glycosylated hemoglobin ,triacylglycerol ,total cholesterol , and low‐density lipoprotein cholesterol were significantly higher than those in the extracranial arterial stenosis group ( all P ＜ 0 .05 ) . T he proportion of elderly ( ≥ 65 years old ) ,male and smokers in the extracranial arterial stenosis group was significantly higher than that in the intracranial arterial stenosis group ( all P ＜0 .05) . Multivariate logistic regression analysis showed that elderly ( ≥65 years old) ,male , and smoking history were independent risk factors for extracranial arterial stenosis ( OR＝ 2 .012 ,1 .637 , 1 .325 ,respectively ;all P ＜0 .05) . While hypertension ,diabetes ,less physical activity ,and high BM I levels were independent risk factors for simple intracranial arterial disease ( OR ＝ 1 .301 ,1 .252 ,1 .248 ,1 .030 , respectively ;all P ＜0 .05) . Conclusions There are significant differences in the distribution characteristics and risk factors of intracranial and extracranial aterial lesions in patients with ischemic stroke in China .

Objective To analyze the correlation between smoking and occurrence of intracranial artery stenosis.Methods From June 2015 to May 2016,a total of 10 711 inpatients with transient ischemic attack (TIA) or ischemic stroke from 20 basel hospitals of nationwide were enrolled using a cross-sectional study,76 patients with unknown smoking and smoking cessation years were excluded.Finally,a total of 10 635 patients were enrolled.Transcranial color coded sonography and/or transcranial Doppler were used evaluate the intracranial artery stenosis lesions.The basic risk factors for cerebrovascular disease (age,sex,smoking and smoking years,whether smoking cessation and years,hypertension,diabetes,hyperlipidemia,atrial fibrillation,and family history of stroke) were recorded.According to the different smoking years,the smoking years were divided into five groups:non-smoking,smoking time ≤10-year,11 to 20-year,21 to 30-year,and >30-year groups for trend chi square test.According to the different smoking cessation years in the smokers,the smoking cessation years were divided into four groups:non-cessation,cessation time 1 to 10-year,11 to 20-year,and >20-year groups for trend chi square test.The effects of different smoking years and different smoking cessation years on the occurrence of intracranial arterial stenosis were analyzed.Results The incidence of intracranial artery stenosis in the smokers (40.4%[1 433/3 547]) was significantly higher than that in the non-smoking patients (29.4%[2 085/7 088]).There was significant difference (χ2=128.850,P<0.01),and the incidence of cerebral infarction in the smokers (91.6%[3 250/3 547]) was significantly higher than the non-smokers (85.0%[6 027/7 088]).There was significant difference (χ2=92.328,P<0.01).Smoking was an independent risk factor for intracranial artery stenosis (OR,1.603;95%CI 1.456-1.765;P<0.01).With the increase of smoking years,the detection rate of intracranial arterial stenosis increased gradually (trend χ2=115.437,P<0.01).Whether giving up smoking had no significant effect on the incidence of intracranial artery stenosis in patients with ≥20 years of smoking (trend χ2=1.043,P=0.307).Conclusions Smoking is an independent risk factor for affecting intracranial artery stenosis;the risk of disease increases with the number of smoking years.Long-term smokers (≥20 years) cannot reduce the effect on intracranial artery stenosis,even if they give up smoking.

Objective To investigate the effect of serum lipid level on carotid artery stenosis in patients with ischemic cerebrovascular disease.Methods Using a multi-center cross-sectional study,10 711 consecutive inpatients with transient ischemic attack (TIA) or ischemic stroke diagnosed clearly in 20 stroke screening and prevention project base hospitals from June 2015 to May 2016 were enrolled.According to the results of carotid ultrasonography,1 560 patients with extracranial carotid artery stenosis rate≥50% screened were enrolled in the study.They were divided into a severe stenosis group (70%-99%) and a mild-moderate stenosis group (<70%).The distribution of total cholesterol (TC),triacylglycerol (TG),low-density lipoprotein cholesterol (LDL-C) and high-density lipoprotein cholesterol (HDL-C) levels in both groups of carotid stenosis patients were analyzed,and the quantitative classification was based on the normal range of serum lipids.The distributions of serum lipid levels in different grades in patients of both groups were compared with the non-parameter test.Results The incidence of dyslipidemia in the severe stenosis group was higher than that in the mild and moderate stenosis group.There was no significant difference between the two groups (54.4%[319/586]vs.48.3%[470/974],P<0.05).Dyslipidemia was an independent risk factor for severe carotid artery stenosis (OR,1.27,95% CI 1.24-1.30,P<0.01).The TC and LDL-C levels in patients of the severe stenosis group were significantly higher than those in the mild-moderate stenosis group (TC:3.98[3.31,4.82]mmol/L vs.3.91[3.31,4.53]mmol/L,LDL-C:2.48[1.86,3.14]vs.2.30[1.79,2.80];all P<0.01).With the increase of TC and LDL-C levels,there was significant differences between the severe stenosis group and the mild-moderate stenosis group (all P<0.05),and the proportions of TC >5.80 mmol/L (7.3%[43/586]vs.0.4%[4/974]) and LDL-C>3.12 mmol/L (26.3%[154/586]vs.10.0%[97/974]) in patients of the severe stenosis group were higher than those in the mild-moderate stenosis group (26.3%[154/586]vs.10.0%[97/974]).Conclusion The high LDL-C and TC levels may increase the incidence of severe carotid artery stenosis or occlusion.

Objective To investigate the differences of distribution characteristics and risk factors of large artery lesions in patients with ischemic cerebrovascular disease in different age groups in order to provide the basis for the prevention and treatment of stroke in different age groups.Methods From June 2015 to May 2016,a total of 10 711 consecutive inpatients with transient ischemic attack (TIA) and ischemic stroke from 20 centers nationwide were enrolled.Each 10 years was used as an age group from 40 years.All the patients were divided into 5 age groups.The differences of the different risk factors for cerebrovascular disease among the 5 groups were compared.All patients were separated by gender.The chi square test was used to compare the incidences of large artery stenosis of the intracranial and external and anterior and posterior circulation,and the number of vascular lesions in the same sex in different age groups.Results (1) The risk factors of elderly patients were mainly hypertension,diabetes mellitus,and atrial fibrillation (χ2=61.938,χ2=13.349,and χ2=55.940;all P<0.01).The smoking history,family history of cerebrovascular disease,and obesity were more frequent among the young and middle-aged people (χ2=131.505,χ2=7.298,and χ2=100.911,all P<0.01).(2) The linear trend chi square test results showed that the proportion of multivessel diseases in female and male extracranial arterial lesions increased gradually with the increase of age.(χ2=54.799,χ2=161.370,all P<0.01).The proportion of multivessel diseases in the intracranial artery in female decreased gradually (χ2=5.328,P=0.021),and that in male did not have obvious trend of change (χ2=0.289,P=0.591).(3) The linear trend chi square test results showed that the incidence of simple intracranial arterial stenosis in female and male intracranial arterial stenosis decreased gradually with the increase of age (χ2=20.090,χ2=42.351,all P<0.01),and the incidence of simple extracranial arterial stenosis increased gradually (χ2=40.311,χ2=90.698,all P<0.01).The incidence of both intracranial and extracranial artery stenoses increased gradually (χ2=12.077,χ2=45.887,all P<0.01).The incidence of simple posterior circulation vascular stenosis increased gradually in female (χ2=16.434,P<0.01),but that did not have obvious trend of change in male (χ2=1.701,P=0.192).The incidence of stenosis of both anterior and posterior arteries in female and male increased gradually (χ2=4.587,P=0.032;χ2=35.156,P<0.01).Conclusions The distribution of atherosclerotic lesions in ischemic cerebrovascular disease of the different age groups was different.No matter female or male patients,the majority of the young and middle-aged patients were intracranial artery lesions,and the elderly patients were mainly extracranial artery lesions.The majority of elderly women had posterior circulation artery lesions.Understanding the characteristics in patients with intracranial arterial lesion in different age groups will help to develop individualized stroke prevention and treatment strategies for the population of different age groups.