Nicotinamide N-methyltransferase (NNMT) is a S-adenosyl-L-methionine (SAM) dependent cytoplasm enzyme,which plays a vital role in the biotransformation and detoxification of many drugs and xenobiotic compounds.Recent studies have revealed abnormal expression of NNMT in many tumors,which may contribute to tumorigenesis and tumor development and radiotherapy or chemotherapy resistance.

Objective To investigate the mRNA expression of secondary lymphoid tissue chemokine (SLC) in human gastric carcinoma. Method The study was designed to investigate semi-quantitatively the expression of SLC mRNA in gastric carcinoma and metastatic lymph nodes by reverse transcription-polymerase chain reaction.Result The expression of SLC mRNA in the gastric cancer tissues was markedly reduced compared with that in adjacent noncancer tissues. The average tumor/normal (T/N) ratio determined by RT-PCR was 0.43?0.08 in 29 patients.Metastatic lymph node/normal ratio was 0.63?0.07.Negative lymph node/normal ratio was 1.19?0.11. As a control,the mean G3PDH T/N ratio was 1.16?0.06,there was no correlation between SLC mRNA expression and clinicopathological characteristics in gastric cancer.ConclusionSLC mRNA expression is suppressed in the gastric tumours. SLC may play an important role in the early stage of carcinogenesis.

Objective To investigate the effect of transabdominal gastroesophageal stapling in management of variceal bleeding in portal hypertension with Hassabi operation and sum up our clinical experience.Methods Retrospective analysis of 48 cases with portal hypertension operated by transabdominal gastroesophageal stapling between May,1998 and Oct.2005.The elimination of oesophagus venous、the rebleeding rate、the operation mortality、the stricture and the fistula rate and the index that influences the liver function were maily observed.Results No case suffered rebleeding and hepatal encephalopathy during the hospitaligation of the patients.Esophageal varices disappeared or reduced in all cases.One case resulted from stricture and one case died of multiple organ failure.Conclusions Transabdominal extensive oesophagogastric devascularization combined with gastrooesophageal stapling is an effective and safe procedure for control of acute variceal haemorrhage with satisfactory short-term control,but the long-term effect needs to be long follow-up for the patients.

AIM:To observe the effect of docosahexaenoic acid ( DHA) on H2 O2-induced apoptosis in human retinal pigment epithelium cells and its molecular mechanism .METHODS: Human retinal pigment epithelium cell line ARPE-19 was cultured in vitro, and 12.5 mmol/L H2 O2 was used to mimic the oxidative stress condition .The cells were treated with 30~100μmol/L DHA for 4~24 h.The expression of heme oxygenase-1 (HO-1) at mRNA and protein levels was detected by real-time PCR and Western blot , respectively .The enzymic activity of HO-1 was measured by colorimetry . Production of reactive oxygen species ( ROS) was determined by fluorescent probe .Activation of NF-E2-related factor 2 (Nrf2) was examined by immunofluorescence method .Apoptosis of ARPE-19 cells was analyzed by flow cytometry .RE-SULTS:The mRNA and protein expression and the enzymic activity of HO-1 were significantly increased in the ARPE-19 cells after DHA treatment .Meanwhile , nuclear translocation of Nrf 2 was also observed .Apoptosis appeared and ROS was produced upon H2O2 incubation.In contrast, DHA at 100 μmol/L significantly abrogated H2O2-induced apoptosis and ROS production.Furthermore, silencing of HO-1 by specific siRNA, or treatment with ZnPP, an inhibitor of HO-1, partly counteracted the protective effect against H 2 O2-induced apoptosis and ROS production .CONCLUSION: DHA protects retinal pigment epithelial cells against oxidative stress via induction of heme oxygenase -1 expression after Nrf2 activation .

Background and purpose:A large number of studies have showed that retinoblastoma gene 1 (RB1) can inhibit the occurrence and development of many tumors, including neuroblastoma, small cell lung cancer, osteosar-coma, pancreatic cancer, breast cancer and so on. RB1 is also closely related to the regulation of cell cycle, differentia-tion, senescence, apoptosis, growth inhibition, etc. The goal of this article is to elucidate whether miR-222 promotes cell proliferation and invasion by targeting RB1, further to explore the molecular mechanism that miR-222 functions as an oncogene in retinoblastoma cells.Methods:miR-222 (miR-222 mimics) and RB1-wt, miR-NC and RB1-wt, miR-222 and RB1-mut, miR-NC (a controlled miR-222 mimics) and RB1-mut were co-transfected into Y79 cells, and luciferase activity was detected by single photon. Retinoblastoma cells were transfected with miR-222 mimics and miR-NC, and the expressions of RB1 protein were detected by Western blot. Retinoblastoma cell proliferation assays were performed by MTS assay when miR-222, miR-NC, RB1 (pcDNA3.1-RB1), vector (pcDNA3.1), miR-222+RB1 and miR-NC+vec-tor were transfected into Y79 cells. The growth and invasion ability of Y79 cells with ectopic expression of miR-222 were evaluated by MTS and Transwell invasion assays.Results:This study demonstrated that miR-222 could promote the luciferase activity of RB1-wt. The expression levels of luciferase reporter gene activity in Y79 cells after transfection with miR-222+RB1-wt were higher than those in the negative control cells (miR-NC+RB1-wt) (P<0.05). The protein expression levels of RB1 in Y79 cells after transfection with miR-222 were lower than those in miR-NC (P<0.05). Overexpression of RB1 inhibited the proliferation of retinoblastoma cells. miR-222 promoted the prolifera-tion of retinoblastoma cells through targeting RB1 (P<0.05). Moreover, there was no signiifcant difference between the cell survival rates of Y79 which were transfected with miR-222+pcDNA3.1-RB1 and miR-NC+pcDNA3.1 (P>0.05). After transfection with miR-222 mimics for 48 h, Transwell invasion assay showed that the number of cells through the basement membrane was (193±10). Compared with the control group (144±11), it could signiifcantly accelerate the invasion of Y79 cells (P<0.01). There was no signiifcant difference between the number of cells through the basement membrane which were transfected with miR-222+pcDNA3.1-RB1 and miR-NC+pcDNA3.1 (P>0.05).Conclusion:miR-222 promotes cell proliferation and invasion by targeting RB1 expression in retinoblastoma cells.

Background Oxydative stress is an important pathogenesis of age-related macular degeneration.Resent evidences indicate that docosahexaenoic acid (DHA) plays an important role during the development of retinal photoreceptor cells and protect the cells against oxydative stress by inducing the expression of heme oxygenase-1 (HO-1).However,whether DHA can induce the expression of HO-1 in human retinal pigment epithelium (RPE) cells is unelucidated.Objective This study was to investigate the effect of DHA on the expression of HO-1 in RPE cells and its molecular mechanism.Methods Human RPE cell line ARPE-19 was cultured in vitro and treated with 30,50,100 and 120 μmol/L DHA for 4 to 24 hours,respectively,and the cells were cultured without DHA as the control group.The cytotoxicity of DHA was detected by lactate dehydrogenase(LDH),and the expression of HO-1 mRNA and protein were detected by real-time PCR and Western blot assay,respectively.The enzymatic activity of HO-1 was detected by colorimetry.The reactive oxygen species (ROS) proportion in the cells was detected using fluorescence probe H2 DCFDA,and immunofluorescence technology was adopted to detect the nuclear translocation of nuclear facotor-E2-related factor 2 (Nrf2).The expression of Nrt2 protein in the cells was detected by Western blot after intervention of ROS inhibitor N-acetylcysteine (NAC) and transfection of Nrf2 small interfering RNA (siRNA).Results The LDH leakage rate was significantly different after 0,3,50,100 and 120 μmol/L DHA treated the cells for 24 hours (F=8.14,P＜0.05),and the LDH leakage rate in the 120 μmol/L DHA group was significantly higher than that of 0,30,50 and 100 μmol/L DHA group (all at P＜0.05).The relative expression levels of HO-1 mRNA and HO-1 protein or HO-1 enzymatic activity in the cells were significantly different among different concentrations of DHA group in 8 hours after treatment (F=16.24,P＜0.05;F=11.34,P＜0.05;F=11.81,P＜0.05),and the expressions of these factors were considerably higher in the 30,50 and 100 μ mol/L DHA group than those in the 0 μmol/L DHA group (all at P＜0.05).The ROS relative fluorescence intensity and nuclear Nrf2 positive cells proportion were statistically significant among different concentrations of DHA groups (F =11.08,P ＜ 0.05;F=16.42,P＜0.05),and the ROS relative fluorescence intensity and nuclear Nrf2 positive cells proportion were evidently higher in the 30,50 and 100 μmol/L DHA group than those in the 0 μmol/L DHA group (all at P＜0.05).The relative expression levels of HO-1 protein and the proportion of nuclear Nrf2 positive cells were significantly lower in the NAC pretreated 100 μmol/L DHA group than those in the 100 μmol/L DHA group.In addition,the HO-1 relative expression level and the positive cells proportion of nuclear Nrf2 were significantly lower in the of Nrf2 siRNA transfection group than those in the blank siRNA transfection group (both at P＜0.05).Conclusions DHA with concentration below 100 μ mol/L can protect RPE cells from oxidative stress by inducting the expression of HO-1 in the cells via ROS/Nrf2 pathway.

Objective To determine the correlation between the expression of interleukin 8 (IL 8) and vascularity in human gastric carcinoma speciemens,and to provide a possible new clinical way for anti angiogenesis of tumor . Methods IL 8 mRNA expression was examined with reverse transcription polymerase chain reaction (RT PCR).IL 8 protein secretion level and its specific expression were determined by enzyme linked immunosorbent assay (ELISA).The number of blood vessels in the gastric carcinoma was determined by antibody against factor Ⅷ associated antigen and immunohistochemical analysis. Results Most of the tumors (26/29,89.7%) and metastatic lymph nodes (17/20,85%) expressed IL 8 at higher levels than that in corresponding normal mucosa of resection end of stomach and negative metastatic lymph node.The expression of IL 8 protein and IL 8 mRNA were at the same level.The level of IL 8 mRNA in the gastric carcinoma tissue correlated strongly and positively with vascularization (P= 0.001).Conclusions There is a positive correlation between IL 8 mRNA expression and the vascularity of gastric carcinoma.IL 8 produced by tumor cells may up regulate the microvascularization in the gastric cancer, and enhance the growth,spreading and lymph node metastasis in human gastric carcinoma.So decreasing the IL 8 expression might inhibit the microvascularization,growth and metastasis of gastric cancer.

Objective To investigate the myocardial protective effects of“integrated strategy”with HOE-642 plus modified K/Mg on canine heart grafts.Methods Sixteen donors-recipient pairs of adult canines were divided into the“integrated strategy”group,i.e.,donor hearts were protected with HOE-642 plus K/Mg(IS,n=8)and the routine method(RM,n=8)group.Both groups un- derwent hypothermia stored for 4 h,followed by orthotopic transplantation.Cardiac heamodynamics was measured and myocardial ultrastructure and myocardial water content were evaluated.Results One of 8 animal died of aortic anastomoses leakage in each group,and the rest could wean from car- diopulmonary bypass successfully.Preservation of left ventricular contractility,as well as left ventric- ular compliance was significantly better in the IS group than in the RM group(P＜0.05),also,per- centage of myocardial water content was significantly lower in the IS group than in the RM group(P＜0.05).Myocardial ultrastructures were not damaged significantly in both groups,however,better myocardial preservation were seen in the IS group.Conclusion Both the clinically used“routine meth- od”and“integrated strategy”might provide safe donor heart preservation for 4 h,but the later scheme conferred more optimal effects with alleviating the myocardial swelling,preserving myocardial ultra- structure integrity and enhancing postischemic-reperfusion cardiac functional recovery.

The web-based PBL teaching plan in pediatrics embodies the network learning environment and learning requirements.The basic design unit is a complete real case with certain width and depth,which can stimulate the students' interests of participation and guide students into a predetermined learning area to achieve desired learning objectives.The article dwelled on the compilation and implementation of the teaching plan of children bronchopneumonia.The first part:teachers showed the case in PBL site and proposed the questions.Students made the Powerpoint after studying and discussing in groups by PBL teaching website,QQ group,SMS platform,etc.The second part:students reported and discussed in groups; the teacher provided the new information and put forward the following-up problems; students consulted the documents and materials through the network again; finally teachers made comments on the results.During the teaching,network should be fully utilized and the questions should be proposed progressively at different levels.Teacher should play a guiding role and emphasize the students' autonomous learning.

Objective To investigate the clinical and pathological features of sacral nerve root lesions and the diagnosis and treatment for these clinical entities.Methods The clinical data of the patients with urine retention or refractory lower urinary tract symptoms (LUTS) caused by sacral nerve root lesions were retrospectively analyzed.Totally 27 patients were included in this study,including 4 cases of acute retention,6 chronic retention and 17 refractory LUTS.All patients had urodynamic disorders and sacral nerve root space-occupying lesions demonstrated by magnetic resonance imaging.All the patients received surgical treatment and were followed up one year or more.Results The pathological findings included simple cyst in 3 cases,ganglioneuroma in 5,cyst wall inflammation in 15,cyst wall hyaline degeneration in 15,and neurodegeneration in 15.Postoperatively,9 of the 10 patients with retention could voluntarily void and 1 remained suprapubic catheter drainage.All 17 patients with refractory LUTS improved significantly in terms of international prostate symptom score,visual analogue scale pain score,quality of life,maximal urinary flow rate and post void residual (P＜0.01).Conclusions Sacral nerve root lesions can be the causes of urinary retention or refractory LUTS.Surgical treatment can improve patient's voiding function and quality of life.