Urban and periurban agriculture (UPA) is the important part of modern agriculture. It can resolve the food supply to city residents, increase employments and improve the urban ecosystem. But without proper management and reasonable programming, UPA also can carry heavy burden to urban environment and impact people's health. This paper specifically analyzed the potential risks of urban agriculture and suggested preventive and control measures.

Objective To observe the effect of PKB gene silencing on the growth of gastric cancer cell line SGC-7901 in vitro.Methods Gene transfection technique was used to transfect AKt2 siRNA into gastric cancer cells.Akt2 expression was detected by RNAi technique,Akt2 protein level was detected by Western blot,and the change of cell cycle distribution and apoptosis of SGC-7901 cells were detected by flow-cytometry,SGC-7901 proliferation was measured by MTT method.Results After SGC-7901 cells transfected with Akt2 siRNA,the expression of protein level decreased obviously(P

Background and purpose: Locoregional infusion chemotherapy such as hepatic artery, or hepaticportal vein infusion is one of the most important treatments for hepatocelluar carcinoma. This study was aimed to investigate the distribution of fluorouracil(5-FU) in rat hepatoma, liver tissue and plasma after administrated by caudal vein or locoregional routes of hepatic artery, hepaticportal vein, and hepaticportal vein with ligated hepatic artery. Methods:Twenty-four tumor-bearing rats were divided into 4 groups randomly, and they were infused with 5-FU through peripheral vein(caudal vein), hepatic artery, hepaticportal vein or hepaticportal vein with ligated hepatic artery, which dose was 20 mg/kg. High performance liquid chromatography was adopted to measure the content of 5-FU in hepatoma, liver tissue and plasma, and the drug penetration rate among them were calculated. Results:The group of hepaticportal vein with ligated hepatic artery reached the highest concentrations of 5-FU in live tissue and hepatoma, which concentrations were (22.1±9.5)μg/g and (16.4±7.2)μg/g. Then was the hepatic artery group, and the concentration of the hepaticportal vein group in the hepatoma focus was much smaller than the former 2 groups, which was (8.9±3.7)μg/g. The peripheral vein group got the lowest concentrations both in the liver tissue and hepatoma, which were (9.4±3.7) and (4.3±2.2)μg/g. The concentrations of 5-FU in the plasma in the peripheral vein group, the hepatic artery group, the group of hepaticportal vein with ligated hepatic artery and the hepaticportal vein group were (26.8±12.5), (16.4±9.7), (15.9±10.1) and (14.9±8.5)μg/mL, which indicated that the drug concentrations of the latter 3 groups were much lower than the former group. The hepatoma/plasma penetration rate of 5-FU in the group of hepaticportal vein with ligated hepatic artery, the hepatic artery group, the hepaticportal vein group and the peripheral vein group were 103.47%, 92.94%, 59.58% and 16.08%. Conclusion: Compared to the peripheral venous bolus injection, locoregional infusion could significantly increase the concentrations of chemotherapy agent in hepatoma focus and liver tissue, and decrease the drug distributions in peripheral blood. And the infusion through hepaticportal vein with ligated hepatic artery and through hepatic artery reaches higher concentrations in the hepatoma focuses, which indicate that they are 2 practical and promising routes for the locoregional chemotherapy of hepatoma.

Objective To investigate the expression of miR-218 in cervical cancer tissues and bioinformatically analyze the target genes of miR-218 to provide theoretical basis on further studies of miR-218 functions in cervical cancer.Methods miRNA array was applied to detect miRNA expression profile in cervical cancer tissues,and real-time RT-PCR was used for validation.The bioinformatic analysis of the target genes of miR-218 involved gene ontology and signal transduction pathway enrichment was performed.Results miR-218 expression significantly decreased in cervical cancer tissues compared with that of normal cervical tissues.The functions of predicted target genes of miR-218 were enriched in biological regulation,adhesion and motion,proteometabolism,cellular differentiation,protein binding and other biological processes and molecular functions.According KEGG pathway database,the predicted target genes involved in pathway in cancer,adherent junction,focal adhesion,prostate cancer,chronic myeloid leukemia,melanoma,and other signal transduction pathways.Conclusions miR-218 expression significantly decreases in cervical cancer tissues.Some of the predicted target genes of miR-218 are significantly enriched in tumor related with signaling pathways.

Military hygiene is one of compulsory courses for undergraduates majored in clinical medicine in military colleges. Aiming at the disconnection between theoretical and practical ability in the traditional teaching process and combining with professional features of military hygiene, teaching reform should give priority to curriculum standards, human resource construction, teaching content and method, teaching quality assessment and feedback system. Meanwhile, teaching idea of‘learning to use’ should be strengthened and teaching scheme in line with the actual needs of military health service security work should be put forward in order to provide new ideas for training military health personnel.

OBJECTIVE: To investigate the effects of episodic hypoxia(EHYP) on liver CYP3A2 and CYP2E1. METHODS: Healthy masculinity rats were divided randomly into five groups: control group, 3 -day EHYP group, 7 -day EHYP group, 14 -day EHYP group, and 28 -day EHYP group. 24 h after the management of EHYP, the rats were anesthetized by intraperitoneal injection, and the eyeball blood 2ml was drawn to prepare serum. The activities of ALT and AST in the serum were determined by enzymatic methods. The activities of liver microsomal erythromycin demethylase(ERD) and aniline hydroxylase(ANH) were detected by spectrophotography. The levels of mRNA expression of CYP3A2,CYP2E1 were assayed with RT-PCR. RESULTS: The serum activities of ALT,AST showed no remarkable change. However, after 7 days of hypoxia, ERD and ANH activities were remarkably elevated, and at 28 days induction rates reached up to155.5% and 42.2%, respectively. Meanwhile, the levels of mRNA expression of CYP3A2,CYP2E1 also increased by 220.5% and 102.8%, respectively. CONCLUSION: Chronic EHYP can remarkably increase the activities of ERD and ANH, whose mechanism is probably related to up-regulating of CYP3A2 and CYP2E1 expression at the transcriptive level.

Objective To investigate microRNA(miRNA)expression profiles in peripheral blood and skin lesions of patients with psoriasis vulgaris(PV), and to seek miRNAs consistently expressed in peripheral blood and skin lesions. Methods A miRNA microarray was used to screen differentially expressed miRNAs in skin lesions and peripheral blood samples between 17 patients with PV and 4 healthy human controls, and real?time fluorescence?based quantitative PCR(RT?qPCR)to verify the differentially expressed miRNAs. The correlations of these differentially expressed miRNAs with psoriasis area and severity index(PASI)score were assessed by Pearson correlation analysis. Results The Agilent human miRNA microarray profiling revealed 15 miRNAs consistently expressed in skin lesions and peripheral blood of patients with PV. Of the 15 miRNAs, 7 were verified as consistently expressed miRNAs by RT?qPCR. Among the 7 miRNAs, the expression intensity of miR?30e?5p, miR?192?5p, miR?17?3p and miR?1227?5p was negatively correlated with PASI scores(all P<0.05), while that of miR?125b?5p, miR?642a?5p and miR?29a?5p was uncorrelated with PASI scores(all P>0.05). Conclusion Some miRNAs are consistently expressed in skin lesions and plasma of PV patients, which are expected to serve as biomarkers for evaluation of psoriasis severity.

Objective To analyze the papers published by domestic scientific research workers in order to improve the academic level of their papers. Methods The papers published by over 3000 domestic scientific research workers were investigated with questionnaires. Their motives to publish papers and the relation between the number of pub-lished papers and the assessment of their performance were analyzed. Results The number of papers published by domestic scientific research workers was increased. However, their academic level was to be further improved. Over quantization of the assessment mechanisms for scientific research increased the external motives to publish papers, thus leading to the insufficient internal motives of them to engage in scientific research. Conclusion A loose and comfortable academic environment should be created for the scientific research workers in order to initiate their in-ternal motives to publish papers. Over quantization of the assessment mechanisms for scientific research should be changed in order to reduce the external motives of domestic scientific research workers to publish papers. Innovative and cultural environment should be created in order to improve the soft power of scientific research in our country.

AIM: To explore the effects of homocysteine on the apoptosis in PC12 cells and the relationship between the apoptosis and the expression of the bcl-2 as well as bax gene. METHODS: Cell viability was determined by MTT assay. Cell apoptosis was assessed by phase-contrast microscope, fluorescence microscopy and flow cytometry (FCM). The expression of bcl-2 and bax mRNA was measured by semiquantitative reverse transcription polymerse chain reaction (RT-PCR). RESULTS: Treatment of PC12 cells with Hcy plus 10 ?mol/L copper for 12 h, in the range of 0.125, 0.25, 0.5, 1.0 mmol/L, caused a great decrease in cell viability: 81%, 79%, 69%, 57%, and induced typical morphological changes of apoptosis in a dose-dependent manner. The apoptosis ratios were respectively 8.00%, 10.37%, 17.26% and 20.19%, respectively. The expression of bcl-2 was significantly decreased (from 0.517 to 0.198) whereas bax was significantly increased (from 0.302 to 0.619). CONCLUSION: Homocysteine plus copper may induce apoptosis in PC12 cells through the down-regulation of bcl-2 and the up-regulation of bax gene expression.

Objective To investigate the effects of cytarabine(Ara-C) on expression of B7 molecules and immunogenicity of acute leukemia (AL) cells. Methods The expression of B7 molecules on fresh AL ceils and on the Ara-C exposed leukemia ceils was detected by FACS cytometer. B7 mRNA in Ara-C treated HL-60 cells were detected by reverse RT-PCR. The stimulation of proliferation of allogeneic PBMC by Ara-C treated HL-60 cells was detected by MTT method. Results B7-2 was weakly expressed in four and positive in three, whereas BT-1 was positive in only one of fourty AL patiens. Ara-C significantly enhanced B7 molecules expression on AL cells. Ara-C could induce higher expression of B7 mRNAs on HL-60 cells.Ara-C treated HL-60 cells could stimulate PBMC proliferation and promote their IFN -γ production.Conclusion Fresh AL cells express low level of B7 molecules. Ara-C enhances the B7 molecules expression on AL cells. The Ara-C treated leukemia cells can significantly stimulate the proliferation of allogeneic PBMC and induce their secretion of IFN-γ.