Objective To evaluate the effects of mild hypothermia performed at different times on the levels of glutamate, Bcl-2 and Bax during global cerebral ischemia-reperfsusion (I/R) in rats. Methods Twenty-four male SD rats weighing 230-270 g were randomly divided into 4 groups according to the time at which mild hypothermia was performed ( n =6 each): group A, B, C and D. Global cerebral ischemia was produced by occlusion of 4 vessels (cauterization of bilateral vertebral arteries and occlusion of bilateral common carotid arteries) in the 4 groups. In group B, C and D, the nasopharyngeal temperature was reduced to 32.5-33.5 ℃ and maintained for 1 h. Ischemia was performed after termination of cooling in group B. While ischemia was performed, cooling was started in group C. While reperfusion was performed, cooling was started in group D. Rewarming was started after termination of cooling in group B, C and D. Samples of dialysate in hippocampal CA1 area were collected every 10 min during 100 min reperfusion for determination of glutamate concentrations by high-performance capillary electrophoresis with laser-induced fluorescence detection ( HPCE-LIF). The brain tissues were taken at 3 h of reperfusion for determination of the expression of Bax and Bcl-2 in hippocampal CA1 area, and the ratio of Bcl-2/Bax was calculated. Results Compared with group A, the glutamate concentrations were significantly decreased, the Bcl-2 expression was up-regulated, the Bax expression was down-regulated and the ratio of Bcl-2/Bax was increased in the other thee groups ( P ＜ 0.05). Compared with group B, the Bcl-2 expression was significantly down-regulated, the Bax expression was up-regulated and the ratio of Bcl-2/Bax was decreased in group C ( P ＜0.05). The glutamate concentrations were significantly increased, the Bax expression was up-regulated and the ratio of Bcl-2/Bax was decreased in group D compared with group C ( P ＜ 0.05 ). Conclusion The earlier cooling is performed, the better the cerebral protective effect is during global cerebral I/R in rats.

We prepared gold nanostar (GNS) through seed growth method firstly,then formation of COX-2 siRNA(siCOX-2) and GNS composite modified with polyethylene glyco (PEG),2-amino-2-deoxy-D-glucos (DG) and 9-D-arginin (9R) was prepared.Mterwords,paclitaxel temperature sensitive liposome (PTX-TSL) was prepared by film dispersion method.Finally,siCOX-2 delivery systerm (PTX-TSL-(siCOX-2(9R/DG-GNS)))was obtained by hydrosulfuryl ligand reaction between siCOX-2 (9R/DG-GNS) and PTX-TSL The successful build of siCOX-2 (9R/DG-GNS) was vetified by nuclear magnetic resonance (NMR),sodium dodecyl sulfate polyacryl amide gel electrophoresis (SDS-PAGE),and ultraviolet spectrophotometry and agarose gel electrophoresis method.Particle size of PTX-TSL-(siCOX-2(9R/DG-GNS)) was (292 ± 14) nm and Zeta potential was about -(2.59 ± 0.12) mV,which were measured by Zetasizer Nano ZS90.The morphology of PTX-TSL-(siCOX-2 (9R/DG-GNS)) measured by transmissionelectronmicroscopy showed homogeneous star structure with phospholipid bilayer on the surface,and it showed good thermal conversion efficiency under radiation of 808 nm laser.Differential scanning calorimetry test showed that PTX-TSL phase transition temperature is about 42.6 ℃.The drug loading content(using dialysis method) and encapsulation efficiency of PTX-TSL were about 7.5％ and 95.4％,at the same time,the release process experiment of PTX-TSL showed that it had a good temperature sensitive release performance.It is hopeful that this siCOX-2 system can be used for reducing drug resistance of PTX and improving the treatment effect of PTX through the synergistic antitumor drug resistance effect of siCOX-2.

OBJECTIVE: To explore the effect of telmisartan on the expression of metadherin in the kidney of mice with unilateral ureter obstruction. METHODS: Eighteen male C57 mice were randomized into sham-operated group, model group and telmisartan treatment group. In the latter two groups, renal interstitial fibrosis as the result of unilateral ureter obstruction (UUO) was induced by unilateral ureteral ligation with or without telmisartan intervention. Renal pathological changes of the mice were assessed using Masson staining, and immunohistochemistry and Western blotting were used to detect the expression of extracellular matrix proteins and metadherin in the kidney of the mice. In the experiment, cultured mouse renal tubular epithelial cells (mTECs) were stimulated with transforming growth factor-β1 (TGF-β1) and transfected with a siRNA targeting metadherin, and the changes in the expressions of extracellular matrix proteins and metadherin were detected using Western blotting. RESULTS: The expressions of extracellular matrix proteins and metadherin increased significantly in the kidney of mice with UUO ( < 0.05). Intervention with telmisartan significantly lowered the expressions of extracellular matrix proteins and metadherin and alleviated the pathology of renal fibrosis in mice with UUO ( < 0.05). In cultured mTECs, siRNA-mediated knockdown of metadherin obviously reversed TGF-β1-induced increase in the expressions of extracellular matrix proteins and metadherin. CONCLUSIONS Telmisartan can suppress the production of extracellular matrix proteins and the expression of metadhein to attenuate UUO-induced renal fibrosis in mice.
Angiotensin II Type 1 Receptor Blockers ; Animals ; Antihypertensive Agents ; Extracellular Matrix Proteins ; metabolism ; Fibrosis ; Kidney ; drug effects ; metabolism ; pathology ; Male ; Membrane Proteins ; genetics ; metabolism ; Mice ; Mice, Inbred C57BL ; RNA, Small Interfering ; Random Allocation ; Telmisartan ; pharmacology ; Transforming Growth Factor beta1 ; pharmacology ; Ureteral Obstruction ; complications ; metabolism