Objective To investigate the influence of cyclooxygenase-2 (COX-2) knock-down on cell proliferation and apoptosis in gastric cancer cell line SGC7901.Methods The mRNA levels of COX-2 in SGC7901 and gastric epithelium cells (GES) were determined by quantitative real-time polymerase chain reaction (qRT-PCR) assays.The influence of COX-2 on the proliferation and apoptosis of cell line SGC7901 was evaluated with methyl thiazolyl tetrazolium (MTT) and fluorescence-activated cell sorter (FACS) assay.Results qRT-PCR assay indicated that the mRNA level of COX-2 in SGC7901 was significantly higher than that in GES (P ＜ 0.01).MTT and FACS assays showed that the proliferation was reversed by COX-2 knock-down in SGC7901 cells.Up-regulated Bax and down-regulated Bcl-2 can inhibit the expression of COX-2.Conclusions COX-2 could contribute to the proliferation of gastric cancer cell line SGC7901.

Objective　To study the viability and histological change of encapsulated rat hepatocytes after being transplanted into abdominal cavity of rat. Methods　The two-step collagenase perfusing method was used to separate hepatocytes from Wistar rat liver. The separated hepatocytes were purified with Percoll density gradient centrifugation and encapsulated by the alginate-barium method. Then the purified hepatocytes were transplanted into abdominal cavity of SD rats (group 1) and the encapsulated hepatocytes were transplanted into abdominal cavity of SD rats (group 2) and Wistar rats (group 3). At different time points post-transplantation, trypan blue stain exclusion was used to determine the viability of recovered hepatocytes. The histological changes of transplanted microencapsulated hepatocytes was examined using HE stain. Results　Twenty-four h after transplantation, the viability of hepatocytes between group 1 and group 2 showed significant difference (P<0.01), but there was no significant difference between group 2 and group 3 (P>0.05). At day 4 and day 7 after transplantation, the viability of hepatocytes showed significant difference between group 1 and group 2, and group 2 and group 3 (P<0.01). At day 14 after transplantation, no significant difference was found in the viability of hepatocytes between group 2 and group 3 (P>0.05). From day 4 post-transplantation, fibrosis overgrowth was found around some microencapsules, and it was more obvious in group 2 than in group 3. Conclusions　 Microencapsulation can provide protection to transplanted hepatocytes from host immunorejection, and thus increase the viability of hepatocytes post transplantation. The existence of inadequately encapsulated microencapsule cause the fibrosis overgrowth around these capsules, resulting in ischemia and subsequent necrosis of the hepatocytes and decreasing hepatocyte viability.

OBJECTIVE:To establish a method for the determination of4major caffeine metabolites and to discuss the significance of which in the evaluation of the activity of drug-metabolizing enzyme CYP1A2.METHODS:The caffeine metabolites in the urine like5-acetylamino-6-formamido-3-methyluric acid(AFMU),1-methyluric acid(1U),1-methylxanthine(1X)and1,7-dimethyluricacid(17U)were determined by RP-HPLC gradient elution method,the ratios of metabolins(AFMU+1X+1U)/17U was calculated,the frequency distribution histogram was drawn and the activity of CYP1A2was evaluated.RESULTS:The mean value of the ratio of the metabolins in the subjects was4.27,which was in normal distribution.CONCLUSION:The method is simple,accurate and rapid,which is suitable for the determination of caffeine metabolites in urine and the study of the activities of CYP1A2.

ObjectiveTo observe the e ff ect of NO precursor or/and NOS inhibitor on the survival of acute liver failure( ALF) rats.MethodsModel of ALF rat was established by resecting 90% of the rat liver and the effect of NO prec ursor or/and NOS inhibitor was observed.Resu ltsAdministration of NO precursor significantly improved the liver, lung, kidney and bowel function. The rats′ survival rate at 24 h, and 72 h increased significantly, whereas NOS inhibitor deteriorated fu nctions of important organs(P

Objective To investigate the timing of endoscopic treatment for acute cholangitis of severe type(ACST) accompanying multiple organ dysfunction syndrome(MODS).Methods On the basis of routine medical measures,such as oxygen inhalation and antishock treatment,9 patients with ACST accompanying MODS were given endoscopic retrograde cholangiopancreatography(ERCP) with endoscopic sphincterotomy(EST),or endoscopic nasobiliary drainage(ENBD) after needle electrode fenestration and stone removal with basket,or endoscopic retrograde biliary drainage(ERBD) with internal stent.Results The endoscopic treatment was successfully accomplished within 35 min in all the 9 patients.Seven patients at stage 1~2 of MODS rehabilitated at 1~2 weeks after treatment,while 2 patients at stage 3 of MODS died in 2 weeks.Conclusions Endoscopic treatment should be applied to patients with ACST at stage 1~2 of MODS as early as possible.For patients with ACST at stage 3~4 of MODS,however,emphasis should be laid on the prevention of organ failure and the reversion of organ functions.

0 05); the increased degree of only AST activity reduced in PE group(P

ObjectiveTo investigate the renal protective effect of recombinant lentivirus encoding adiponectin gene on streptozocin-induced early diabetic nephropathy(DN) mice,and to explore its potential mechanism.Methods Forty C57BL/6 mice were randomly divided into normal control group(NC group,n=10),diabetic nephropathy group(DN group,n=10),LentiIRES-EGFP treatment group(DL group,n=10) and Lenti-Acdc-IRES-EGFP treatment group (DA group,n=10).After 8 weeks of recombinant lentivirus injection,kidney to body weight ratio (KW/BW),mean glomerular volume(MGV),fractional mesangial area(FMA),24 h urinary protein excretion(UTP),Scr,BUN,serum albumin and adiponectin were measured.Renal pathological changes were evaluated by electron microscopy.Proliferation of glomendar and tubulointerstitial cells was assessed by immunohistochemistry using PCNA antibody.The phosphorylation of AMP-activated protein kinase(AMPK) and mammalian target of rapamycin protein(mTOR) were detected by Western blotting.Results Adiponectin was successfully over-expressed in STZ-induced DN mice after lentivirus injection.KW/BW,MGV,FMA and UTP were significantly decreased in DA group as compared to DN group and DL group(P＜0.05),but were increased as compared to NC group(P＜0.05).DA group animals had significantly fewer PCNA-positive cells than DN group and DL group(P＜0.01).DA group mice had higher p-AMPK level and lower p-mTOR level as compared to DN group and DL group(P＜0.01).Conclusion Over-expression of adiponectin has beneficial effect on early DN and attenuates aberrant proliferation of renal cells via AMPKmTOR pathway.

Objective To establish Walker-256 transplantation tumor model in SD Rats.To study of R2 * signal changes on murine Walker-256 tumor after inhaling Carbogen by blood oxygen level dependent (BOLD)-MR,and to explore the feasibility of BOLD-MRI on detecting tumor hypoxia.Methods Walker-256 tumor cell implanted subcutaneously in right lower abdomen of 95 female SD rats.MR was performed on the tumor-forming rats when the maximum diameter of tumor reached 1-3 cm,using a 3.0 T MR scanner equipped with a 3 inch animal surface coil BOLD-MRI was done by using a multiecho SPGR sequence during inhaling air and at 10 minute after inhaling Carbogen,respectively.All images were transferred to GE ADW 4.3 workstation,then a baseline R2* (R2 * a) and R2 * (R2 * b) after inhaling Carbogen of tumor was calculated using R2 Star analysis software and △R2 * was calculated through △R2 * =R2 * b-R2 * a,meanwhile the volume of tumor were calculated as well.The difference of R2 * signal preand post-inhaling of Carbogen was compared with a paired t test,Pearson correlation was calculated between R2 * a,△R2 * and the volume of tumor,respectively.The correlation between △R2 * and R2 * a was also assessed by Pearson correlation.Results Sixty-eight of ninety-five female SD rats formed the tumor (71.6％).The volume of tumor was from 352 to 13 173 mm3.Mean △R2* decreased significantly (-2.26 ±3.90) s-1 from (41.18 ±22.29) s-1 during breathing air to(38.91 ±21.35) s-1 10 min after inhaling Carbogen (t =4.01,P ＜ 0.01).△R2 * was inversely correlated with R2 * (r =-0.32,P ＜ 0.05).The △R2 * was well correlated with volume of tumor (r =0.35,P ＜ 0.05),but R2 * a was not correlated with volume of tumor(r =-0.03,P ＞ 0.05).Conclusions BOLD-MRI can detect the R2 * signal change of murine Walker-256 tumor pre-and post-inhaling of Carbogen.The R2 * signal showed significant decrease after inhaling Carbogen,however,the individual variation was remarkable.

Objective To evaluate the effects of recombinant lentivirus encoding human apM1 gene ( LentiapM1-EGFP) on platelet-derived growth factor (PDGF) induced human mesangial cell (HMC) proliferation and intracellular AMP-activated protein kinase(AMPK) signaling pathway.Methods Protein expression of apM1 in cell culture supernatant of HMC transfected with Lenti-apM1-EGFP was detected by ELISA.The effect of human adiponectin on cell proliferation and cell cycle was assessed by [ 3 H ] thymidine incorporation assay and Flow cytometry respectively.The phosphorylation of AMPK was detected by Western blotting.Results Lenti-apM1-EGFP had no significant toxicity on HMC.The 50 multiplicity of infection (MOI) of the Lenti-apM1-EGFP efficiently infected HMC,and made it stable expression of adiponectin protein ( 149.6 ± 12.8 ) μg/L.PDGF-induced HMCs proliferation was significantly inhibited by adiponectin.When co-treatment with compound C,an AMPK inhibitor,the inhibitory effort was reversed.The phosphorylation level of AMPK was increased in HMC transfected Lenti-apM1-EGFP compared to that of control.Conclusions Adiponectin antagonizes stimulatory effect of platelet-derived growth factor on mesangial cell proliferation by AMPK signaling.

Research on osteoporosis diagnosis has always been a critical isuue in the field of international academia and medicine. Recent progress in quantitative ultrasound (QUS) has suggested that ultrasound, due to its obvious advantages, be considered as an effective and noninvasive tool for assessment of bone status and diagnosis of osteoporosis. This paper presents the principle and recent development in the ultrasonic assessment of bone status and osteoporosis including assessment with through-transmission and backscattering measurement, and also introduces the latest progress in ultrasonic axial transmission technique.Limitations of current research are discussed and suggestions are proposed for future research.