MiR-338-3p Enhances Ovarian Cancer Cell Sensitivity to Cisplatin by Downregulating WNT2B

PURPOSE: Chemoresistance is a concern in ovarian cancer patients, in whom survival remains. MicroRNA, a novel class of small RNAs, have frequently been found to be dysregulated in human malignancies and to act as negative regulators of gene expression. This study aimed to explore the function of miR-338-3p in cisplatin resistance in ovarian cancer and potential molecular mechanisms thereof. MATERIALS AND METHODS: The expression levels of miR-338-3p and WNT2B in ovarian cancer tissues and cells were estimated by real-time quantitative polymerase chain reaction (RT-qPCR). In addition, 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-2H-tetrazol-3-ium bromide (MTT), transwell, and flow cytometry assays were used to assess biological role of miR-338-3p in vitro. Western blot assay was conducted to measure protein expression of WNT2B, epithelial-mesenchymal transition (EMT)-related proteins, and apoptosis-related proteins. The relationship between miR-338-3p and WNT2B was confirmed by dual-luciferase reporter. Finally, a xenograft tumor model was developed to explore the effects of overexpression of miR-338-3p on tumor growth in ovarian cancer in vivo. RESULTS: MiR-338-3p was downregulated in cisplatin resistant ovarian cancer tissues and cells. Mechanistically, high expression of miR-338-3p enhanced cell sensitivity to cisplatin by inhibiting proliferation, motility, and EMT and by promoting apoptosis via targeting WNT2B expression in vitro. Furthermore, overexpression of miR-338-3p increased cisplatin sensitivity among ovarian cancer in an in vivo xenograft tumor model. CONCLUSION: MiR-338-3p enhances the sensitivity of ovarian cancer cells to cisplatin by downregulating WNT2B.

Application of low-concentration contrast agent and low-dose technology in 320-slice CT pulmonary angiography / 医疗卫生装备

Objective To explore the feasibility of low-concentration contrast agent and low-dose technology for pulmonary angiography by comparing the image quality and radiation doses to the patient by different tube voltages and concentrations of contrast agents.Methods Totally 60 patients suspected with pulmonary embolism were divided into C, L1 and L2 groups, of which,Group C had the scanning parameters of 120 kV and 350 mgI/ml,Group L1 had the parameters as 100 kV and 350 mgI/ml and Group L2 had the parameters of 100 kV and 270 mgI/ml.The three groups had the tube voltage as 500 mA, the contrast agent dose as 25 ml,physiological saline dose as 40 ml and flow rate as 4.5 ml/s.SPSS 19.0 software was used to compare and analyze the CT values of pulmonary artery segment,superior vena cava and ascending aorta,main pulmonary artery noises,the image quality as well as the radiation doses of volume scanning. Results The three groups had the main pulmonary aortas and their branches display clearly to meet clinical requirements.When compared with Group C,Group L1 had higher CT values of the main pulmonary aorta and its branches,higher image noise while lower radiation dose (P<0.01);Group L2 had equivalent CT values of the main pulmonary aorta and its branches (P>0.05),higher image noise while lower radiation dose (P<0.01).When compared with Group L1,Group L2 had lower CT values of the main pulmonary aorta and its branches (P<0.01),and equivalent image noise and radiation dose (P>0.05).Conclusion Low-concentration contrast agent and low-dose technology gains feasibility and advantages when used in 320-slice CT pulmonary angiography.

Vasorelaxational effects of procyanidins on rabbit aorta in vitro and decreasing arterial blood pressure in vivo / 中国中药杂志

<p><b>OBJECTIVE</b>To study the vasodilation effect of the procyanidin (PC) extracted from grape seeds on rabbit thoracic aortic rings in vitro, decreasing blood pressure in vivo and the possible mechanism.</p><p><b>METHOD</b>Rabbits aortic rings were isolated and were divided into six groups including removal of endothelium, integrity of endothelium, 1 x 10(-5) mol X L(-1) indomethacin (Indo), 1 x 10(-5) mol x L(-1) propranolol (Prop), 1 x 10(-4) mol x L(-1) N(omega)-nitro-L-arginine (L-NNA) and 1 x 10(-5) mol x L(-1) methylene blue (MB). Then the thoracic aortic rings were treated with PC with cumulative concentrations of 1.25, 2.5, 5.0 mg x L(-1) respectively and the changes of tension were recorded, and investigate the effect of 40 mg x L(-1) PC on the contraction of aortic smooth muscles, thoracic aortic rings were pre-treated with NA (1 x 10(-8) to approximately 1 x 10(-5) mol x L(-1)), KCl (6.3 to approximately 100 mmol x L(-1)) and CaCl2 (1 x 10(-5) to approximately 1 x 10(-5) mol x L(-1)) followed by treatment with PC. Then, rabbits common carotid artery was intubated and arterial blood pressure in vivo was recorded. PC with cumulative concentrations of 4.0, 8.0, 16, 32, 64, 84 mg x kg(-1) was injected into vein and the changes of arterial blood pressure were observed.</p><p><b>RESULT</b>PC could relax isolated rabbit aorta and showedan obvious concentration-dependent relaxation (r = 0. 63, P < 0.001). The relaxant effect of PC was significantly reduced by removal of endothelium and by treatment with nitric oxide synthase inhibitor L-NNA, or guanylyl cyclase inhibitor MB. In addition PC could decrease the dose response curves of aortic rings to NA, KCl and CaCl2. PC has a significant concentration-dependent negative effect on arterial blood pressure in vivo (r = 0.92, P < 0.001).</p><p><b>CONCLUSION</b>PC has a vasodilation effect not only in an endothelium-dependent, nitric oxide involved manner, but in inhibition of calcium release and blockage of potential-dependent calcium channels. PC could decrease the rabbit's arterial blood pressure significantly in vivo.</p>

Preparation and in vitro targeting of sterically stabilized liposomes modified with chimeric TNT-3 monoclonal antibody / 药学学报

<p><b>AIM</b>To prepare sterically stabilized liposomes modified with chimeric TNT-3 monoclonal antibody (chTNT-3) and investigate their immunoreactivity and in vitro targeting.</p><p><b>METHODS</b>An end-group functionalized polyethylene glycol-lipid derivative (pyridylthiopropionoylamino-polyethylene glycol-hydrogenated soy phosphatidylethanolamine, PDP-PEG-HSPE) was synthesized and incorporated to sterically stabilized liposomes. After mild thiolysis of the PDP groups by dithiothreitol, liposomes were covalently linked with maleimide-derivatized chTNT-3 and formed sterically stabilized immunoliposomes. Coupling efficiency, antibody density, size distribution, immunoreactivity of chTNT-3-modified sterically stabilized liposomes (chTNT-3-SLs) and specific binding properties of the chTNT-3-SLs to fixed Raji cells were determined, separately.</p><p><b>RESULTS</b>Higher initial Ab/PDP-PEG-HSPE molar ratios resulted in higher antibody density on the surface of liposomes but lower coupling efficiency. The optimal coupling efficiency of 71% was obtained while antibody density in liposome was 106 microg antibody/micromol phospholipids (as initial antibody/PDP-PEG-HSPE = 1 : 10). The chTNT-3-SLs had a narrow size distribution after extrusion and the mean size of this immunoliposomes was (115 +/- 33) nm. The immunoreactivity of chTNT-3 can be preserved after efficient attachment of maleimide-derivatized chTNT-3 to the surface of liposomes. But calculated per antibody concentration, the immunoreactivity of chTNT-3-SLs would obviously decrease compared to that of chTNT-3 or chTNT-3 derivatives. Significantly higher binding of chTNT-3-SLs to fixed Raji cells directed by chTNT-3 was obtained compared to other preparations in serial dilutions (P < 0.01).</p><p><b>CONCLUSION</b>chTNT-3-SLs prepared by PDP-PEG-HSPE method remained most immunoreactivity of chTNT-3 and was able to bind nuclear antigens in vitro.</p>

Spectrophotometry on measuring the size of liposomes / 药学学报

<p><b>AIM</b>To establish a spectrophotometric method for measurement of the sizes of liposomes for evaluating physical stability of liposomes.</p><p><b>METHODS</b>The sterically stabilized liposomes (SLs) were prepared by ethanol injection method and extrusion method. The mean cumulant diameters (D) of the vesicles were determined by electron microscopy and dynamic light scattering. On the basis of Rayleigh-Gans-Debye theory, the absorbance at 436 nm per unit lipid concentration (A436 nm/Cp) was measured as a function of vesicle diameter.</p><p><b>RESULTS</b>log(A436 nm/Cp) was closely related to logD (r2 > or = 0.93, n = 5).</p><p><b>CONCLUSION</b>The absorbance of liposomes reflect their relative sizes and can be used to evaluate physical stability of liposomes.</p>