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Many efforts have been made to understand excitotoxicity and develop neuroprotectants for the therapy of ischemic stroke. The narrow treatment time window is still to be solved. Given that the ischemic core expanded over days, treatment with an extended time window is anticipated. Bestrophin 1 (BEST1) belongs to a bestrophin family of calcium-activated chloride channels. We revealed an increase in neuronal BEST1 expression and function within the peri-infarct from 8 to 48 h after ischemic stroke in mice. Interfering the protein expression or inhibiting the channel function of BEST1 by genetic manipulation displayed neuroprotective effects and improved motor functional deficits. Using electrophysiological recordings, we demonstrated that extrasynaptic glutamate release through BEST1 channel resulted in delayed excitotoxicity. Finally, we confirmed the therapeutic efficacy of pharmacological inhibition of BEST1 during 6-72 h post-ischemia in rodents. This delayed treatment prevented the expansion of infarct volume and the exacerbation of neurological functions. Our study identifies the glutamate-releasing BEST1 channel as a potential therapeutic target against ischemic stroke with a wide time window.
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OBJECTIVE: To improve the standard detection method for acetaldehyde, butyraldehyde and isobutyraldehyde in the air of workplace. METHODS: Acetaldehyde, butyraldehyde and isobutyraldehyde in the air of workplace were collected using silica gel tube, desorbed with 45.0% ethanol, separated by a capillary column and detected by a flame ionization detector. RESULTS: The linear range of this method for detecting acetaldehyde, butyraldehyde and isobutyraldehyde were 1.57-1 568.00, 1.60-1 600.00 and 1.59-1 588.00 mg/L, respectively. All the correlation coefficients were greater than 0.999. The detection limits were 0.52, 0.46 and 0.54 mg/L, respectively. The desorption efficiency was 91.0%-103.0%. The within-run relative standard deviation(RSD) was 0.7%-1.7%.The between-run RSD was 2.0%-3.7%. The samples could be stored for at least 10 days at room temperature. CONCLUSION: This method can be used for simultaneous detection of acetaldehyde, butyraldehyde and isobutyraldehyde in the air of workplace.
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OBJECTIVE: To improve the standard detection method for acetonitrile in workplace air. METHODS: Acetonitrile in the air of workplace was collected by silica gel, eluted with methanol, separated and determined by gas chromatography with flame ionization detection. RESULTS: After the improvement of the method, the linear range of acetonitrile was 1.57-1 574.00 mg/L, and the correlation coefficient was 0.999 98. The detection limit was 0.29 mg/L and the minimum detection concentration was 0.19 mg/m~(3 )(collected sample volume was 1.5 L). The average desorption efficiency was 93.1%-98.9%. The within-run and between-run precision was 2.6%-3.3% and 1.7%-3.6%, respectively. The samples could be stored at room temperature for at least 10 days. CONCLUSION: The improved method is precisied, accurate and simple to operate, which is suitable for determination of acetonitrile in workplace air.
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@#To synthesize the folic acid-alliinase conjugate(FA-Alliinase), and to study its targeting and antitumor activity on cervical cancer HeLa cells. FA-Alliinase I and FA-Alliinase II were synthesized by two methods. The couping ratios of two conjugates measured were 12 and 31, respectively. The FA-Alliinase II with high coupling ratio was selected and its structure was characterized preliminarily. The activity of alliinase retained about 50% in FA-Alliinase II determined by HPLC. The specific effect of FA-Alliinase II on HeLa cells was observed by confocal laser and flow cytometry. The antitumor activity of conjugate combined with alliin was determined by MTT, and IC50 of alliin was(127. 6±2. 3)μmol/L. This study provides a direct evaluation method for the synthesis and optimization of FA-Alliinase.
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Objective To evaluate 16-SCT in diagnosing aeute appendicitis.Methods The CT findings of 34 cases were retrospectively analyzed.These cases were all proved acute appendicitis by surgical-pathology.Results 30 cases were confirmed by CT,with accuracy 88% (30/34).The diameter of 28 appendix was more than 6mm;2 collapsed with thickening wall.Periappendiceal fat stranding could be seen in 25 cases.Perforated appendicitis happened in 4 cases.Abscess performed in 2 cases.3 cases were missed,1 misdiagnosed.Conclusion 16-SCT could confirm acute appendicitis and its complication timely and accurately.
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Objective To evaluate the value of 16-slice spiral computed tomography(SCT)in diagnosing acute aortic syndrome.Methods Thirty-four cases with acute aortic syndrome underwent 16-slice SCT,performed with unenhanced,contrast-enhanced scanning of bolus tracking and three-dimensional reconstruction.The CT findings of these cases were analysed.Results Twenty-three of them were confirmed Aortic Dessection(AD),the true and false lumen,intimal flap,extent involved and complications of which were all revealed.Six cases were confirmed intramural aortic hematoma(IMH),with features of ring or crescent-shaped non-enhanced thickening wall around the aorta.Five cases were confirmed penetrating atherosclerotic ulcer(PAU),with features of niche sign outstanding the lumen of the aorta.Conclusion Acute aortic syndrome can he diagnosed exactly and completely by 16-slice SCT,which can provide valuable information to select therapeutic methods.
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Objective To observe the effect of ecdysterone(EDS)on the level of VEGF protein in the brain,angiogenesis and neurologic function after focal cerebral ischemia in rats.Methods Rat with focal cerebral ischemia were established by occluding their middle cerebral artery.The established rats(n=36)were randomly and equally divided into EDS treatment group and ischemia group.EDS(20 mg?kg-1?d-1 for 7 d)was intraperitoneally injected into the rats of EDS treatment group 2 h after operation,and the animal of ischemia group received an intraperitoneal injection of the same solvent as in EDS group.Another 6 rats served as normal control.Rats were sacrificed in 7,14 and 21 d after operation,and the VEGF protein level and microvessel density(MVD)was detected with immunohistochemical methods and analyzed quantitatively with image system.Effect of EDS on neurologic recovery following brain ischemia were assessed using the neurologic severity scores(NSS).Results VEGF expression was not seen in normal control,and was higher in ischemia group than in the EDS treatment group at day 7 and 14,but the significant difference was only observed at day 7(P
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Objective To analyze the change of the shear stress in atherosclerotic carotid artery of rabbits and its effect on the plaque and intimia-media pathological morphology. Methods Totally 36 male Japanese White rabbits were randomly divided into blank control group (n=6), sham operation control group (n=6) and the surgery group (n=24). The blank control group was fed by normal diet. The sham operation control group was fed by the high-cholesterol diet. The surgery group was fed by high-cholesterol diet and treated by air-drying. In the 2nd, 4th, 8th and 12th week after operation, the hemodynamic parameters were measured using Color Doppler Flow Imaging. Blood viscosity was determined and the degree of artery stenosis was showed by digital subtraction angiography (DSA). The stenosis rate, mean shear stress, intimia-media ratio and mean integrated optical densities (IOD) of media smooth muscle cells (SMC) were calculated respectively. Results The typical atherosclerotic plaque was presented in surgery group. The thickness of media and mean IOD of SMC were increased at the 2nd week after operation. However, following the increase of the stenosis rate and shear stress, the flow field was changed on the stenotic artery. The pathological morphology showed the character of vulnerable plaque such a large lipid core, thin fibrous cap, and plaque rupture at 4th, 8th week after operation. The media showed atrophy and became thin, mean IOD of SMC was decreased. Statistic analysis showed significant difference in the 2 week group compared with other group. Conclusion Following the increase in the degree of stenosis, the flow shear stress is increased, turbulent flow presents, and flow field changes on the stenotic artery. Thus the plaque become unstable , and the vessel occurs remodeling.
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Objective: To investigate the inhibitory effects of Ad K5 on the proliferation of endothelial cells and the growth of mammary cancer. Methods: Kringle 5 of human plasminogen was constructed by PCR, and then cloned to plasmid pCA13. Recombinant adenovirus Ad K5 was obtained through homologous recombination in 293 cells. The inhibition effect of Ad K5 on cell proliferation was observed in vitro . The tumor size was measured at different intervals to observe the antitumoral effect of Ad K5 in vivo .Results: The mRNA expression of K5 gene was detected in Ad K5 infected B Cap 37 cells. Ad K5 inhibited the growth of ECV 304 cells, but had almost no effects on B Cap 37 cells. It seemed that Ad K5 could inhibit endothelial cells but not kill the cancer cells directly. Ad K5 could also inhibit the tumor growth in vivo. Conclusion: Ad K5 could inhibit the growth of solid mammary tumor.
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Aim To explore the effect of nNOS specific inhibitor 7-nitrioindazole(7-NI) on the neurogenesis after focal cerebral ischemia in the adult mice dentate gyrus.Methods Focal cerebral ischemia was induced by middle cerebral artery occlusion(MCAO).A bromodeoxyuridine(BrdU) method was used to identify the proliferated cells in hippocampal dentate gyrus.Step-down test was performed to assay the learning and memory function.Results The number of BrdU~+ cells was increased in the ipsilateral but not contralateral dentate gyrus after focal cerebral ischemia.7-NI promoted the increment in the ipsilateral dentate gyrus significantly.7-NI also improved the survival of the new-born cells,as well as the learning and memory function of ischemic mice.Conclusion Our results indicate that nNOS down-regulates the neurogenesis after focal cerebral ischemia.