Objective To prepare nifedipine( NF)sustained-release pellet tablets,and study of its release behavior in vitro. Methods Soluplus was selected as a carrier to prepare solid dispersion of NF by hot melt extrusion technique( HME), and the ratio of the drug to carrier was 1:1. The samples were validated as the solid dispersion by differential scanning calorimetry(DSC). Extrusion-spheronization technique was introduced to prepare NF pellets and EudragitRS 30D was used as the coating material. The NF sustained-release tablets were prepared by direct compression of the coated pellets and suitable excipients. Results The release data in vitro proved that the drug release from the tablets was steady and complete over 24 hours. Conclusion The release of NF from sustained-release tablets is slow and steady. The method is easy to operate. The in vitro drug release pattern follows first-order kinetics.

Purpose To evaluate the differential diagnostic value of conventional ultrasound in the ureteral polyps and ureteral carcinoma via continuous observation.Materials and Methods The conventional ultrasound of patients with ureteral polyps and ureteral carcinoma treated in Shaanxi Provincial People's Hospital were retrospectively analyzed from June 2015 to June 2022.According to the pathological results,all participants were divided into the ureteral polyp group(98 cases)and the ureteral carcinoma group(151 cases).All clinical and ultrasound data were recorded,and the differences of echo,blood flow and peristalsis were compared between the two groups.Results There were significant differences in ureteral peristalsis,color Doppler flow distribution,periureteral tissue thickening,increased echo,and hydronephrosis(χ2=197.50,138.89,26.97,36.13,all P<0.05)between the two groups.Low echo was predominant in both groups[67(68.37)vs.114(75.50)],with no significant difference(χ2=1.52,P>0.05).In the ureteral polyp group,67 cases were found in the upper ureter,89 cases were observed continuously with common peristalsis,and 73 cases with color blood flow were mostly central blood flow,while in the ureteral cancer group,85 cases were found in the middle and lower ureter,148 cases showed almost no peristalsis,and 122 cases with color blood flow were mostly peripheral blood flow.Conclusion There are some differences in clinical features such as the location as well as whether hydronephrosis between ureteral polyps and carcinoma.Peristalsis can provide the differential diagnosis for ureteral polyps and ureteral carcinoma via continuous observation.

Objective:To assess the combination of conventional ultrasound with contrast-enhanced ultrasound(CEUS)in the diagnosis of urothelial carcinoma(UC)of the renal pelvis in elderly patients.Methods:Sixty-seven elderly patients with a histopathologic diagnosis of UC of the renal pelvis and surgically treated at our hospital between April 2015 and March 2023 were retrospectively analyzed.Characteristics of regular preoperative 2D ultrasound, color Doppler flow imaging(CDFI)and CEUS were examined.Results:Of 67 patients, 49(73.13%)were found to have localized lesions in the renal pelvis and renal calyces.Lesions in 53 patients(79.10%)could be clearly identified by conventional ultrasound, with 46(86.79%)being isoechoic or hypoechoic, and 7(13.21%)being hyperechoic.Analysis of tumor blood flow by CDFI found 22 cases(41.51%)with avascular lesions, 21(39.62%)with hypovascular lesions and 10(18.87%)with hypervascular lesions.The average value of the resistance index(RI)was 0.64.Enhancement was seen in 62 lesions(92.54%)by CEUS after injection of SonoVue.Compared with the cortex of the ipsilateral kidney, a slow enhancement pattern was observed in 46(74.19%), 14(22.58%)showed simultaneous enhancement, and 2(3.23%)showed fast enhancement.At peak enhancement, 43 lesions(69.35%)had hypo-enhancement, 10(16.13%)had iso-enhancement, and 9(14.52%)had hyper-enhancement, compared with the cortex.Concerning the homogeneity of enhancement, 16(25.81%)displayed heterogeneous enhancement, with tumor necrosis or hemorrhage, and 46(74.19%)had homogeneous enhancement.When the contrast agent washout rate was assessed, a fast washout pattern was observed in 53(85.48%), synchronous washout in 6(9.68%), and slow washout in 3(4.84%).Conclusions:UC of the renal pelvis mostly shows isoechoic and hypoechoic lesions on conventional ultrasound, avascular or hypo-vascular lesions on CDFI, and slow-in, fast-out and hypo-enhancement on CEUS, compared with the cortex.Conventional ultrasound combined with CEUS can help improve the diagnostic accuracy of UC of the renal pelvis.

Background::Carotid intima-media thickness (IMT) and diameter, stiffness, and wave reflections, are independent and important clinical biomarkers and risk predictors for cardiovascular diseases. The purpose of the present study was to establish nationwide reference values of carotid properties for healthy Chinese adults and to explore potential clinical determinants.Methods::A total of 3053 healthy Han Chinese adults (1922 women) aged 18-79 years were enrolled at 28 collaborating tertiary centers throughout China between April 2021 and July 2022. The real-time tracking of common carotid artery walls was achieved by the radio frequency (RF) ultrasound system. The IMT, diameter, compliance coefficient, β stiffness, local pulse wave velocity (PWV), local systolic blood pressure, augmented pressure (AP), and augmentation index (AIx) were then automatically measured and reported. Data were stratified by age groups and sex. The relationships between age and carotid property parameters were analyzed by Jonckheere-Terpstra test and simple linear regressions. The major clinical determinants of carotid properties were identified by Pearson’s correlation, multiple linear regression, and analyses of covariance.Results::All the parameters of carotid properties demonstrated significantly age-related trajectories. Women showed thinner IMT, smaller carotid diameter, larger AP, and AIx than men. The β stiffness and PWV were significantly higher in men than women before forties, but the differences reversed after that. The increase rate of carotid IMT (5.5 μm/year in women and 5.8 μm/year in men) and diameter (0.03 mm/year in both men and women) were similar between men and women. For the stiffness and wave reflections, women showed significantly larger age-related variations than men as demonstrated by steeper regression slopes (all P for age by sex interaction <0.05). The blood pressures, body mass index (BMI), and triglyceride levels were identified as major clinical determinants of carotid properties with adjustment of age and sex. Conclusions::The age- and sex-specific reference values of carotid properties measured by RF ultrasound for healthy Chinese adults were established. The blood pressures, BMI, and triglyceride levels should be considered for clinical application of corresponding reference values.