1.Preparation of amphiphilic superparamagnetic composite particles with tumor targeted MRI contrast agent
Junheng GU ; Qingyun ZHANG ; Wei ZHANG ; Xinlin YANG
Chinese Journal of Tissue Engineering Research 2014;(30):4823-4830
BACKGROUND:Superparamagnetic iron oxide nanoparticles (Fe3O4 NPs) have been widely used in MRI. It is vital to prepare the superparamagnetic MRI contrast agent with high stability, biocompatibility and tumor targeting in order to prevent the aggregation of Fe 3 O 4 NPs and realize the high-precision diagnose of tumor. OBJECTIVE:To prepare the amphiphilic superparamagnetic composite particles with tumor targeting mediated by folate receptor. METHODS:The stable amphiphilic superparamagnetic composite particles with tumor targeting function were prepared by coating the Fe3O4 NPs with a Pluronic F127-folic acid conjugate, which was synthesized via an esterification reaction between the carboxyl group of the tumor targeting molecule, folic acid and the hydroxyl group of an amphiphilic triblock copolymer, Pluronic F127. The resultant Pluronic F127-folic acid-Fe3O4 composite particles were characterized by transmission electron microscopy, Fourier transform infrared-spectra, UV-vis absorption spectra, thermal gravimetric analysis, vibrating sample magnetometer and T2-weighted imaging. WST assay was used to characterize their cytotoxicity preliminarily. RESULTS AND CONCLUSION:The Pluronic F127-folic acid conjugates were prepared via esterification reaction. Then Fe 3 O 4 NPs were wrapped with Pluronic F127-folic acid to result in the superparamagnetic composite particles with wel dispersion and biocompatibility. The size of most superparamagnetic composite particles was less than 200 nm and the size of Fe 3 O 4 core was 10-20 nm from the observation of transmission electron microscopy. The results from the Fourier transform infrared-spectra and UV-vis absorption spectroscop confirmed that folic acid molecules were modified on the surface of the superparamagnetic composite particles successful y. The mass ratio of Pluronic F127-folic acid conjugate was determined by thermal gravimetric analysis as 27.2 wt%in the resultant Pluronic F127-folic acid-Fe 3 O 4 composite particles. The saturated magnetic intensity of the superparamagnetic composite particles was 47.35 emu/g by vibrating sample magnetometer and the relaxation rate was 0.025×106 mol/s from MRI. The WST assay showed the negligible cellcytotoxicity of Pluronic F127-folic acid-Fe3O4. The superparamagnetic composite particles have potential application as the MRI contrast agents with tumor targeting, and the Pluronic F127-folic acid-Fe 3 O 4 composite particles is expected to be used as a MRI contrast agent for tumor targeting.
2.Changes of skin perfusion after photodynamic therapy for port wine stain
Lan JIANG ; Ying GU ; Xianghong LI ; Xiumei ZHAO ; Junheng LI ; Kai WANG ; Jie LIANG ; Yuming PAN ; Yu ZHANG
Chinese Medical Journal 1998;111(2):136-138
Objective To obtain an objective assessment of the curative effectiveness of photodynamic therapy (PDT) for port wine stain (PWS), we investigate the relationship between the microvascular perfusion changes of PWS and the blanching of the lesions before and after PDT. Methods Twenty-four patients (18 females and 6 males with a total of 28 lesions) suffering from PWS were treated with PDT. The lesions of various extents were located on the face and neck. After intravenous injection of photosensitizer hepatoporphyrin derivative (HpD), the copper vapor laser was adopted as light source and the lesions of PWS were irradiated. The laser Doppler perfusion imager (LDI) was used to measure the microcirculatory perfusion of PWS before and after PDT and comparison with the normal skin was done.Results All the lesions showed remarkable decrease of tissue perfusion after PDT. It was shown that the mean, maximal and minimal values of tissue perfusion in the pre-treatment group were significantly higher than those in control group (P<0.01). Six months after PDT, the mean, maximal and minimal values of perfusion with the lesions were reduced, with significant difference from pre-treatment group (P<0.01), but no significant difference from control's. The colors of lesions were correlated with decrease of microcirculatory perfusion, which became lightened close to normal skin color without causing any scarring.Conclusions PDT is one of the most effective modalities for PWS. The microcirculation perfusion can reflect the degrees of PWS objectively. The curative effectiveness of PDT for PWS is due to tissue microcirculation response.
3.Blood pressure management and chronic complications in type 2 diabetes
Junheng ZHANG ; Siyu WANG ; Le CAI ; Wanting XIE ; Haoqing GU ; Qianqian YANG ; Xiaoyun ZHANG ; Xiaoli XU ; Xuan ZHAO ; Yu XU ; Jie CHENG
Chinese Journal of Endocrinology and Metabolism 2024;40(8):710-715
Hypertension heightens the risk of cardiovascular and renal complications in individuals with type 2 diabetes mellitus. Optimal blood pressure (BP) management is crucial for preventing these complications. This review consolidates evidence from clinical trials and major BP management guidelines to shed light on key aspects of hypertension management in diabetes. It addresses BP thresholds to initiate antihypertensive treatment, optimal BP control targets, recommended first-line antihypertensive edications, and BP monitoring plan for the prevention of chronic complications in type 2 diabetes.