BACKGROUND: Within the bone marrow stroma there exists a subset of non-hematopoietic stem cells referred to as marrow stromal cells or mesenchymal stem cells. Mesenchymal stem cells (MSCs) are a group of cells with highly capability of self-renew and potential of multilineage differentiation, these properties make them present a promising prospect for clinical practice. Of particular concern is hepatogenic potential that can be used for liver-directed stem cell therapy and transplantation. However, the culture system has not been developed.OBJECTIVE: To explore whether human MSCs are able to differentiate into functional hepatocyte-like cells with hepatocyte growth factor (HGF) and basic fibroblast growth factor (bFGF) in vitro.DESIGN : Open study.SETTING: Department of Infectious Disease and Institute of Urology Surgery, First Affiliated Hospital, Nanchang University.MATERIALS: The study was performed in the Institute of Urolgoy Surgery, the First Affiliated Hospital of Nanchang University from July 2004 to March 2005. Bone marrow was donated by healthy adult with informed consent. DMEM/F12 medium (Gibco); insulin, transferrin, human epidermal growth factor (EGF); human HGF; monoclonal antibodies against human AFP; FITC-conjugated rabbit anti-mouse IgG (Sigma); human bFGF (Invitrogen); monoclonal antibodies against human CK18 and CK19 (Chemicon); fetal bovine serum (Si jiqin, Hangzhou).METHODS: Bone marrow (10 mL) in this study was aspirated from the iliac crest of healthy donors. MSCs were isolated by density gradient centrifugation in combination with plastic adherence. For hepatic differentiation, the 4th- to 8th-passage human MSCs seeded on 24-well tissue culture plates coated with 0.1% gelatin, at 1×104 MSCs/mL, were serum deprived for 2 days, in DMEM/F12 supplemented with 10 μg/L EGF, 10 μg/L bFGF, 5 mg/L insulin and 5 mg/L transferrin. Differentiation was induced by treating MSCs with differentiation medium, consisting of DMEWF12 supplemented with 10 μg/L bFGF, 20 μg/L HGF, 5 mg/L insulin, 5 mg/L transferrin. Medium changes were performed every three days. MSCs without HGF and bFGF in medium served as the control. In the differentiating period, the concentration of AFP in the suernatant was determined dynamically by radioimmunoassay (RIA). The hepatic surface phenotype including AFP, CK18 and CK19 were identified by immunofluorescent staining at day 0, 7, 14, 21 and 28. Glycogen storage was detected by Periodic Acid-Schiff (PAS) staining.MAIN OUTCOME MEASURES: ① the morphological changes of induced MSCs; ② the concentration of AFP in the supernatant; ③ the hepatic surface phenotype; ④ glycogen storage.RESULTS: ① After 14 days ofinduction, the fibroblast-like morphology of human MSCs was lost and cells became broadened and fiattened. After prolonged culture, polygonal cells were seen and further matured hepatocyte-like colonies were seen by day 28. ② The concentration of AFP in the supernatant was first detected on day 14, at a concentration of 0.1 μg/mL, and increased to 0.4 μg/mL by day 17, then decreased to 0.3 μg/mL by day 21. ③ Immunofiuorescent staining showed the expression of AFP and CK18 until day 14. The expression of CK19 was detected by day 28. ④ Glycogen storage could be detected by day 21.CONCLUSION: Human bone marrow MSCs are able to differentiate into functional hepatocyte-like cells and may sere as a new source of cells for cell therapy of hepatic diseases.

Objective To investigate the effects of curcumin on the proliferation, cell cycle distribution, and apoptosis of the acute myeloid leukemic cell line HL 60 and the hepatocarcinoma cell line QGY. Methods MTT method was used to detect the biological activities of curcumin at different concentrations and at different time. The cell cycle distribution was analyzed by flow cytometry, and changes of the cellular ultrastructure were observed by electronic microscopy. Results Curcumin could inhabit the growth of HL 60 and QGY in dose and time dependent manners. IC50 values of curcumin at 72 h to HL 60 and QGY were 24.8 ?mol/L and 49.5 ?mol/L, respectively. The cell growth of HL 60 was arrested at S and G 2/M stages (apoptosis peak: 8.65%), and that of QGY was arrested at S stage (apoptosis peak: 10.84%). Curcumin could lead to fat degeneration in HL 60 cells and cell degeneration and necrosis of QGY cells, resulting in apoptosis of QGY cells. Conclusion Curcumin has inhibitory effect on the growth of HL 60 cells through its anti proliferation and on QGY cells through the induction of apoptosis of QGY cells.

Carrying out the training of critical thinking in pathophysiology teaching is appropriate, and the medical students critical thinking ability can be achieved via construction of the awareness, and diverse teaching methods which include questioning, exploration and discussion.

As the expansion of classroom teaching,the emerging network-aided instruction could provid novel methods to improve pathophysiological teaching.With the methodological superiority of network and information technology,the network-aided pathophysiological teaching protocol should be well designed to attract learning interest and improve comprehensive abilities of the students.

BACKGROUND:Polyvinyl alcohol is a biocompatible and biodegradable polymer. It is widely used in clinical areas because of its water-soluble, film forming, emulsification, adhesiveness, tasteless, and nontoxic.
OBJECTIVE:To review the applications of polyvinyl alcohol and its composite materials in bone, cartilage, skin, vessels and other tissue engineering scaffolds.
METHODS:A computer-based online search of CNKI database from January 2000 to December 2011, PubMed database and Elsevier (ScienceDirect) database from January 1980 to December 2012, was performed by the first author with key words of“poly(vinyl alcohol), composite material, tissue engineering scaffold”both in Chinese and English. Literatures concerning polyvinyl alcohol and its composite materials in bone, cartilage, skin, vessels and other tissue engineering scaffolds were included, and repetitive research was excluded.
RESULTS AND CONCLUSION:Although there are not enough strength, complications and other shortcomings in vivo, due to its good biocompatibility and biodegradable properties, polyvinyl alcohol and its composite
materials have made great progress in tissue engineering applications from the laboratory to the pre-clinical
research. But its long-term effects need further research. It wil be a main research aim of scaffold materials in the future to improve the interaction of cel s with the scaffold materials by surface modification, to prepare biomimetic materials by cel microenvironment simulation, to improve the hydrophilicity, the adhesion of cel s, and cel
differentiation and proliferation, to bionic the structure and function of the natural extracel ular matrix by building three-dimensional porous structure and control ing the release of cel growth factors, to meet the need of tissue regeneration by congruity or harmony of degradation and mechanical strength.

AIM:To evaluate the morphological and functional changes of retinas induced by treatment of tunicamycin with optical coherence tomography (OCT) in rats.METHODS:Totally 60 SD rats were randomly divided into 3 groups (20 in each group), 0.5mg/kg (in low dose group), 1.5mg/kg (in high dose group) tunicamycin were injected into vitreous cavity and saline (9g/L NaCl) were injected in the same dose as a control group.Changes of retinas were observed by OCT on the 1,7 and 14d after treatment of tunicamycin.Then the rats were sacrificed, retinas were taken out and embedded by the paraffin, tissue sections and the HE staining were performed.RESULTS:OCT results suggested that tunicamycin played damage effects on retinal morphology and structure which appeared a time-and dose-dependent.Fundus photography results suggested that 2wk after tunicamycin treatments, with the gradually changing of tunicamycin concentration, peripheral retinal and macular region became pale color gradually, edema occurred in optic disk, retinal vessels appeared thinner in the high dose group, optic nerve came out atrophy.Fluorescein angiography confirmed that tunicamycin injection in vitreous cavity 2wk later, retinal vessels injury occurred, resulted in leaking of intravascular contrast agent from peripheral to the central part of the retinas.Electrophysiological data showed that retinal electrogram occurred disorder induced by tunicamycin, such as the amplitude of a wave, b wave decreased gradually, even closed to zero, which was very different from control significantly (P<0.05).HE staining of paraffin sections showed that retina injuries induced by tunicamycin were in dose-time dependent, which was consistent with the results of OCT.CONCLUSION: Clinical retinal diseases could be simulated by retinal damage animal model induced by tunicamycin treatment.OCT detection offered real-time images of the retinal cross-section, which provided a helpful non-invasive method for detecting and evaluating the retinal damages.

Objective To investigate the effects of BCG ( Bacillus Calmette-Guerin) infection on NKG2D (natural killer group 2, member D) ligands (MICA, MICB, ULBP1 and ULBP2) expressed on macrophages and to further analyze the effects of baicalin on these NKG2D ligands and the cytotoxic activity of NK cells. Methods PMA ( phorbol 12-myristate 13-acetate) was used to induce the differentiation of THP-1 cells into macrophages. The THP-1-derived macrophages were infected with BCG and then treated with baicalin. The expression of MICA, MICB, ULBP1 and ULBP2 at mRNA and protein levels were meas-ured by real-time PCR and Western blot assay. The BCG-infected macrophages were co-cultured with NK cells derived from human PBMC for 4 h. Real-Time Cell Analyzer ( RTCA DP) was used to evaluate the cy-totoxic activity of NK cells. Results The expression of MICA, MICB, ULBP1 and ULBP2 at mRNA level and the expression of MICA and ULBP1 at protein level were upregulated after infecting the macrophages with BCG. The expression of MICA and ULBP1 at mRNA and protein levels and the killing activity of NK cells were significantly enhanced after treating the BCG-infected macrophages with baicalin (1 mg/L) for 72 h. Conclusion BCG infection could induce the expression of NKG2D ligands on human macrophages, but could not effectively active the NK cells. Baicalin could enhance the cytotoxic activity of NK cells by further up-regulating the expression of NKG2D ligands on BCG-infected macrophages.

Objective To explore clinieopathologieal features and prognosis in a high grade malignancy group of colorectal mueinous carcinoma, signet-ring cell carcinoma and low-differentiated carcinoma. Methods Retrospective analysis and follow-up were made on 148 patients with colorectal mucinous carcinoma, 55 patients with signet-ring cell carcinoma and 281 low- differentiated carcinoma treated in our hospital from 1988 to 2006. Obtained data were analyzed by SPSS13.0. Related factors underwent x2 analysis, survival analysis were estimated using Kaplan-Meier method and compared using the Log-rank test. Results Coloreetal signet-ring cell carcinoma were significantly different from mucinous carcinoma and low- differentiated carcinoma in gender, age, tumor location, bowel obstruction, operative modus, tumor embolism, tumor infiltration and lymph node metastasis(x2 = 7, 67,38.4,86.0,14.5,93.7,17.3,62. 1,24. 4,56.17 ,P <0.05). Median survival time was 24 months in signet-ring cell carcinoma, 47 months in mueinous carcinoma and 49 months in low- differentiated carcinoma. The difference is of significance(x2 = 21.3, P < 0.05). Conclusions Clinicopathological characteristics and prognosis of colorectal signet-ring cell carcinoma, mueinous carcinoma and low- differentiated carcinoma is of significant difference(P < 0.05). Malignancy of signet-ring cell carcinoma is higher with worse prognosis.

Objective To explore the clinicopathological characteristics as prognostic factors in patients with colorectal signet-ring cell carcinoma. Methods Clinical data of 62 patients of colorectal signet-ring cell carcinoma and 281 patients of colorectal low-differentiated adenocarcinoma were retrospectively analyzed. COX Proportional Hazards Model was used in multivariate analysis. Results Colorectal signet-ring cell carcinoma occurred more frequently in young patients and most of them located in the rectum. Gender, preoperative CEA, pathological type and liver metastasis were not statistically different from low-differentiated adenocarcinoma (X2=0.07,0.04,0.06,1.79,P>0.05).Bowel obstruction, operative modalities, tumor embolism, infiltration depth, lymph node metastasis were statistically different from low-differentiated adenocarcinoma (X2=8.96,75.1,18.5,72.0,7.44,P<0.05). Median survival time was 28 months in patients of colorectal signet-ring cell carcinoma and 49 months in patients of colorectal low-differentiated adenocarcinoma. The difference was statistically significant (X2=12.51,P<0.05). Infiltration depth, lymph node metastasis, operative modalities and postoperative adjunctive therapy were independent prognostic factors based on a multivariate analysis of the COX Proportional Hazards Model. Conclusions The biological malignancy of colorectal signet-ring cell carcinoma is higher than that of low-differentiated adenocarcinoma in colorectal carcinoma. Radical resection and postoperative adjunctive therapy were effective treatment methods.

Objective To evaluate the clinical presentation,pathologic features,diagnosis and treatment of hepatic angiomyohponm(HAML).Methods Retrospective analysis was made on 22 HAML cases in terms of clinical finding,images,pathologic examination and surgical treatment.Results Of the 22 patients,6 were male and 16 were female.The average age was 48.2 years.Seventeen patients had no clinical symptoms.None had the history of hepatitis virus infection.None of them was complicated with renal AML.None had tlle history of taking oral contraceptives in the sixteen female patients.Serum AFP、CEA、CA19-9、CA242 levels were all within normal limits.The correct diagnostic rate of BUS.CT and MRI was 2l%(4/19)、23.5%(4/17)and 25%(2/8),respectively.All tumorts were single nodule with a diameter of 4～17 cm,without complete capsula.All these 22 patients underwent tumor resection,including partial liver resection in 17 patients,left hemihepatectomy in 5.One patient died of postoperative complication,one patient suffered from temporary bile leak.The HMB45 positive rate by immunohistochemical method was 100%.Extramedullary hemopoiesis was found in 4 patients.Follow up of 6 months to 17 years in 91%(20/22)patients found no tumor recurrence. Conclusions HAML had no specifiC symptoms.The preoperative imaging diagnosis is difficult.Surgical resection is the therapy of choice for HAML.