The application of genetic engineering technology in modern agriculture shows its outstanding role in dealing with food shortage. Traditional medicinal plant cultivation and collection have also faced with challenges, such as lack of resources, deterioration of environment, germplasm of recession and a series of problems. Genetic engineering can be used to improve the disease resistance, insect resistance, herbicides resistant ability of medicinal plant, also can improve the medicinal plant yield and increase the content of active substances in medicinal plants. Thus, the potent biotechnology can play an important role in protection and large area planting of medicinal plants. In the development of medicinal plant genetic engineering, the safety of transgenic medicinal plants should also be paid attention to. A set of scientific safety evaluation and judgment standard which is suitable for transgenic medicinal plants should be established based on the recognition of the particularity of medicinal plants.
Genetic Engineering ; Plant Diseases ; genetics ; prevention & control ; Plants, Genetically Modified ; chemistry ; genetics ; growth & development ; metabolism ; Plants, Medicinal ; chemistry ; genetics ; growth & development ; metabolism

AIM: To study the protective effect of bone marrow stromal cells (MSCs) on ischemia /reperfusion hippocampal slices. METHODS: Ischemia/reperfusion models of hippocampal slices from newborn rats were established. MSCs obtained from adult bone marrow were cultured, isolated and purified. Cell death was assessed using propidium iodide fluorescence. And brain-derived neurotrophic factor (BDNF) expression in MSCs was determined by immunocytochemistry and Western blot. RESULTS: Maximal dead cells appeared in hippocampal slices 3 to 7 days after reperfusion. When the slices were co-cultured with MSCs, only a few cells were dead. The protective effect of MSCs on the slices was diminished significantly when anti-BDNF antibody was added to the medium. The protein of BDNF was faintly expressed in MSCs under normal conditions. When MSCs were co-cultured with ischemia /reperfusion hippocampal slices, the expression of BDNF in MSCs was increased gradually especially when co-cultured for 3 to 7 days. However, MSCs co-cultured with normal hippocampal slices expressed BDNF at a lower level at any times of co-culture. CONCLUSIONS: In an in vitro model of simulated ischemia, MSCs reduce cell death. Ischemia/reperfusion hippocampal slices co-cultured with MSCs promote the expression of BDNF in MSCs, which in turn protect the ischemic neurons.

China ; Death ; Humans ; Tissue and Organ Procurement

Objective　To investigate the effect of amniotic membrane on the proliferation of YAC-1 in vitro. Methods　The YAC-1 cells were cultured with amniotic membrane and their proliferation were observed by MTT automated colorimetry on the lst day， the 3rd day and the 7th day respectively.Results　Amniotic membrane could significantly enhance the proliferation of YAC-1 on the lst day, the 3rd day and the 7th day respectively after having been seeded (P＜0.01).Conclusion　Amniotic membrane can enhance the proliferation of tumor cells (YAC-1), which should be paid attention to during amniotic membrane transplantation for treating ocular surface lesion caused by epibulbar tumors. ［Rec Adv Ophthalmol 2000;20(5)∶317-318］

Objective To investigate the expression of CD133 in human nasopharyngeal carcinoma cell line SUNE,and to detect proliferative and differential ability of CD133+ tumor cells in vitro,and to identify tumor-like stem cells in SUNE.Methods Immunocytochemical staining method and flow cytometry were used to detect the expression of putative tumor-initiated cell marker CD133 in nasopharyngeal carcinoma cell line SUNE,and the isolation technique with immunomagnetic beads was applied to purify CD133+ cells.The proliferative ability of CD133+ tumor cells in vitro was estimated by MTT assay,and the proliferative ability of CD133+,CD133-and control SUNE cells were statistically compared.Finally,the immunocytochemical staining method and flow cytometry were used to detect differential ability of CD133+ tumor cells in vitro.Results CD133 was positively expressed only in 0.35% of the cells in nasopharyngeal carcinoma cell line SUNE.In the serum-free medium RPM I1640,the UV optical density of the CD133+ tumor cells enriched with immunomagnetic beads was 0.317?0.007,0.370?0.002 and 0.558?0.004 at 3,5 and 7 days,respectively.Compared with CD133-cells and control SUNE cells,CD133+ cells showed increased proliferative capacity(P

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.

0.05).The recurrence of pterygium was related to the age.If the age increased five years,the risk of recurrence decreased 18.1%. Conclusion The application of MMC(during) the operation could decrease the recurrence rate of pterygium.The recurrence rate of pterygium was not related to the time of application of 0.02% MMC,and detainment for 3 min was enough during the operation.

Evidence-based medicine emphasizes making project of diagnosis and therapy on the basis of the most objective research results. The current condition in which domestic medicine is dominant in hepatobiliary surgery and teaching needs to be changed urgently. The procedure of application of evidence-based medicine in teaching of hepatobiliary surgery is explained by an actual example. Evidence-based medicine plays an important role in teaching and quick progress in all of the hepatobiliary surgery.

Biological performances of Ni-Cr porcelain alloy are highly correlated with released metallic ions. Released metal ions from Ni-Cr porcelain alloy, particularly Ni, Be can induce inflammation of the adjacent periodontal tissue and oral mucosa. In vitro evidence has indicated that the immune response can be altered by various metal ions. Allergic reactions due to metallic dental restorations have been documented. Ni has especially been identified as being highly allergenic. The cytotoxicity and corrosion level of Ni-Cr porcelain alloy is increased after recasting. The Ni-Cr porcelain alloy produced according to technology requirements has good biological safety. Ni-Cr porcelain alloy released a few of metal ions which might induce allergy and density of adjacent periodontal tissues, for the stimulation effect of these metal ions. There is no evidence to suggest that Ni-Cr porcelain alloy restorations has systemic toxicity or carcinogenic/genotoxic effect to human.

Objective To explore the value of endoscopic nasopancreatic drainage (NPD) in the prevention of post-endoscopic retrograde cholangiopancreatography pancreatitis (PEP) in a high-risk population.Methods From April 2009 to February 2012,a total of 105 cases of PEP high risk population were collected and divided into non NPD group (n=58) and NPD group (n=47) according to the situation during the endoscopic retrograde cholangiopancreatography(ERCP) operation.NPD was placed in NPD group,the head of the drainage passed the neck of pancreas under X-ray.Nasobiliary drainage or no drainage was assigned to the group of non NPD group according to the situation during operation.x2 test and t-test were performed for comparing and analyzing the clinical data before and post operation,the incidence and risk ratio of PEP between the two groups.Results Twenty-four hours after ERCP,the mean level of serum amylase at 24 h (t=2.419),the degree of abdominal pain (t3h=2.585,t24h=7.236) and relief time (t=4.996) of NPD group were better than those of non NPD group (all P＜0.05).The incidence of PEP in NPD group was 6.7％(3/45) and non NPD group was 29.3 ％ (17/58),the incidence of PEP in the NPD group was significantly lower than that in the non NPD group (x2 =8.304,P＜0.01),and the relative risk was 0.172 (95％CI:0.047 to 0.632,P＜0.01).Conclusion The regular placement of endoscopic NPD is a practical,effective and easy way to prevent PEP in high risk population.