Objective To study the pretreatment with prostaglandin E1 ( PGE1 ) on acute superior mesenteric ar-tery ( SMA) ischemia reperfusion injury of intestinal cell in rats. Methods 18 healthy male SD rats were randomly divided into control group, sham operation group and experimental group. IRI of SMA model was made by clamping the SMA for one hour and two hours after reperfusion in the control group and the experimental group,respectively. PGE1(20 μg/kg) was injected from the tail vein in the control group and the experimental group. Character of pa-thology of small intestine was examined. The expression of Bax and Bcl-2 in small intestine cells and change of IF-ABP and DAO in serum were detected. Results Pathologic changes showed that there was no change in the control group;while in the sham operation group,chorionic epithelium mucosa ulceration and hemorrhage and necrosis oc-curred more seriously than that in the experimental group. Expression of Bax and Bcl-2 was higher in the sham op-eration group and the experimental group than that in the control group(P<0. 05), and it was obviously lower in the experimental group than in the sham operation group(P<0. 05). The content of IFABP and DAO in blood ser-um:it was higher in the sham operation group and the experimental group than in the control group ( P<0. 05 ) , and it was lower in the experimental group than in the sham operation group(P<0. 05). Conclusion PGE1 can relieve the alvine necrosis caused by rats' mesenteric reperfusion injury after acute artery ischemia and thus protect damaged mucosa of small intestine.

Objective To investigate the genotype distribution of hepatitis C virus (HCV) in Guangdong Province by linear probe assay (LiPA) and core,non-structural protein 5B (NS5B) sequence analysis,and to evaluate the accuracy of LiPA for genotyping.MethodsOne hundred and ten HCV specimens from chronic hepatitis C (CHC) patients in Guangdong Province were genotyped by both core,NS5B sequence analysis and INNO-LiPA 2.0.The data were then analyzed with SPSS 10.0 software.ResultsAmong the 110 specimens,core and NS5B fragment could be amplified from 97 and 62 specimens,respectively,while both fragments were obtained from 57 specimens. The results of genotyping by core sequence analysis were completely consistent with the results of NS5B sequencing.One hundred and two specimens were classified into five subtypes,i.e.genotype 1a,2a,3a,3b,6a,with frequencies of 61.8％ (64),9.8％ (10),3.9％ (4),3.9％ (4),20.6％ (21),respectively.All but genotype 6 strains can be genotyped correctly by using INNO-LiPA 2.0.However,only subtype 1b and 3b could be genotyped accurately.81.5％ genotype 6a strains were genotyped as 1b by mistake. Conclusions Genotype 6a has become the second most prevalent genotype in Guangdong Province.The LiPA cannot distinguish genotype 6a from 1b strains accurately which needs further investigation.

BACKGROUND: Schwann cells are the seed cells of neural repair, and it is a key to harvest a large number of Schwann cells with high purity and activity. OBJECTIVE: To compare the in vitro culture, purification, and morphology of Schwann cells between neonatal and adult rats, and investigate a simple and feasible culture method to harvest high-purity Schwann cells. METHODS: Totally 30 Sprague-Dawley rats, comprising 20 neonatal (1-3 days after birth, neonatal group) and 10 adult (weighing 150-200 g, adult group) rats, were included. Following double-enzyme digestion and two incubations, Schwann cells were isolated and purified by differential attachment. Cell morphology and attaching speed were determined through the use of inverted microscope. Cells were counted and cell purity was calculated. Cell proliferative ability was detected by MTT microcolorimetry. Curves of cell proliferation in each group were depicted to determine proliferative speed. Schwann cells were identified by S-100 immunochemistry.RESULTS AND CONCLUSION: Compared with fibroblasts, neonatal rat Schwann cells exhibited faster, while adult rat Schwann cells showed slower, attaching speed. Both neonatal and adult groups yielded over 96% cell purity. MTT microcolorimetry results revealed that Schwann cells proliferated actively in neonatal and adult groups. Cell proliferative curves show that neonatal rat Schwann cells proliferated faster than adult rat Schwann cells (P < 0.05). S-100 immunochemistry results showed positive results in both groups. All these findings suggest that double-enzyme digestion and two incubations followed by differential attachment is a satisfactory method to harvest considerable Schwann cells with high purity and activity. Neonatal rat Schwann cells show stronger proliferative, attaching capacities than adult rat Schwann cells.

Chinese materia medica (CMM) plays an important role both in the disease prevention and therapy system and also in natural drug screening. Biotechnology exhibits applicable prospects in modern research of CMM with progress of natural science and technologies. Amplification fragment length polymorphism (AFLP), restriction fragment length polymorphism (RFLP), random amplification polymorphism of DNA (RAPD), and microsatellite DNA have been used to discriminate and breed herbal varieties. Genetic transformation and techniques of tissue and cell culture are explored to protect herbal resouces and to produce active components or parts on a commercial scale. High throughput technologies of proteome and biochip are expected to probe molecular targets and routes of CMM with the changes of proteome and gene expression. The results can be helpful to novel drug development and secondary exploitation, so as to promote the modernization process of CMM.

BACKGROUND:Schwann cells transplantation can change the local micro-environment and help to repair the injured neural tissue, so getting a large number of highly purified and active Schwann cells is the key of the study. OBJECTIVE: To search for a simple and rapid method to extract and purify the Schwann cells.METHODS: Rats were divided randomly into two groups, namely, in vivo pre-degeneration of sciatic nerve resection group and untreated control group, with 20 rats in each group. Under sterile conditions, the rat sciatic nerves were cut off at post-operative 7 days, Schwann cells were extracted by using mixed enzyme digestion and tissue mass transplantation; through low enzyme digestion and twice inoculation to differential adhesion, Schwann cells were purified. Cell morphology was observed under phase contrast microscope and identified by mmunofluorescence staining; cell purity was calculated; MTT method assay was used to determine the capacity of cell proliferation.RESULTS AND CONCLUSION: At 7 days of the culture, the experimental group showed the typical bipolar or bipolar Schwann cells, with connections between cells; in control group, cell processes were shorter and less associated with the surrounding cells. Following S-100 immunofluorescence staining, cells were positive for green expression.Cells proliferated rapidly in the experimental group and formed a swirling shape at 15 days, there were a relatively small number of fibroblasts, at the purity of 96.1%; in the control group, the cells proliferated slowly, with many fibroblasts at a low purity. MTT assay showed that primary cultured Schwann cell proliferated weakly in both groups; compared with the control group, the proliferation of subcultured Schwann cells in the experimental group was markedly increased (P < 0.05 or 0.01), and reached a peak 3 4 days later. The results confirmed that in vivo denaturing, in vitro hybrid enzyme digestion, tissue mass transplantation combined with low enzyme digestion, separation of double-differential adhesion of Schwann cells is a simple and rapid method to extract and purify Schwann cells.

It has been 4 years since Natural Health Products Regulations(NHPRs)was enforced by Health Canada in January of 2004.In the past time,how will it affect the marketed Traditional Chinese Medicines(TCM) in Canadian market? Recently,The two TCM products Carditionic Pill (Fufang Danshen Diwan)and Chaihu Pill from Tasly have been newly certificated by Health Canada recently.Taking them as examples,this article introduces the current status.opportunities and challenges for the regulation of TCM in Canada.and suggests that the domestic TCM corporations push the product registration as soon as possible.

Objective To study the clinical application value of multi-slice spiral CT iliac venography.Methods The iliac venography with multi-slice spiral CT was performed in 50 cases.150 mgI/ml contrast medium at 2.5～3.0 ml/s was administered via the veins of dorsum of foot and the delayed time was 16～22 s,the images were reconstructed by several methods.The imaging quality and imaging characteristic of iliac vein disease were analyzed.Results Helical CT venography was performed successfully in all patients.Venography showed vein complete occlusion in 31 cases,vessel stenosis or filling defect in 9 cases,normally in 10 cases.The quality of images included:excellent 24%(12/50),good 60%(30/50),bad 16%(8/50),the collectivity was 84%(42/50).Conclusion The multi-slice spiral CT iliac venography is of certain clinical applied value.

Objective:To study the effect of CsA on CD4+CD25+T cells from DO11.10 mice after immunization with OVA.Methods:The amount of spleen CD4+CD25+T cells and Foxp3+T cells was detected by means of flow cytometry (FCM).Results:After immunization with OVA,the ratios of CD4+CD25+T cells to CD4+T cells and Foxp3+T cells to CD4+CD25+T cells elevated in spleen,but CsA significantly decreased the percentage of CD4+CD25+T cells and CD4+CD25+Foxp3+T cells under either naive state or immune reaction state.Conclusion:CsA inhibits immune responses,while it also suppresses immune tolerance.

Objective To investigate the guidance of the endoscopic ultrasonography for the surgery selec-tion of patients with low rectal cancerthrough analyzing the accuracy of endoscopic ultrasonography in preoperative TN staging. Methods Eighty-seven cases with low rectal cancer received preoperative endoscopic ultrasonography examination,the preoperative staging and the postoperative pathologic comparison. The EUS accuracy of preopera-tive staging of rectal cancer was evaluated. Results The preoperative staging with endoscopic ultrasonography for patients with low rectal cancer,100% in T1 stage,96.0% in T2 stage,85.7% inT3 stage,and 100% in T4 stage. The preoperative staging and the postoperative pathologic comparison in T stage were consistent(Kappa = 0.903, P < 0.05). The preoperative staging with endoscopic ultrasonography for patients with low rectal cancer ,87.0% in N0 stage,78.6% in N1 stage,and 100% in N2. The preoperative and the postoperative pathologic comparisons in N stage were consistent(Kappa = 0.768,P < 0.05). Conclusion The endoscopic ultrasonography had a certain advantage in the clinical preoperative evaluation for patients with low rectal cancer ,especially for invasion depth and the judgment of lymph node metastasis ,with a higher accuracy.