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.

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.

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.

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.

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 compare the histopathological changes after neo-adjuvant radiotherapy and to elucidate the mechanism of radiotherapy in rectal cancer. Methods: 80 patients with rectal cancer in pTNM stage Ⅱ or Ⅲ were enrolled between April 2000 and December 2002.They were randomly assigned to surgery alone or preoperative neo-adjuvant radiotherapy.The conventional radiotherapy scheme was followed: 40 Gy in 2.0 Gy fractions.The treatment last 4 weeks and it is usually followed by an interval of 1-2 weeks before the operation.Pathological changes including necrosis of tumor and changes of matrix and vessels were graded. Results: Significant tumor regression(RCRG 1) was seen in 14 cases(35 percent) after radiotherapy,while partially tumor regression(RCRG 2) was seen in 18 cases(45 percent).Significant necrosis was observed in 72.5 percent of cases after preoperative radiotherapy,most foci of adenocarcinoma were replaced by fibrosis in 80 percent of cases,and intimal thickening in most of the vessels were seen in 77.5 percent of cases.The frequency of these pathological changes after radiotherapy was significantly more than control group. Conclusion: Necrosis,fibrosis and thickening of vascular intima in the rectal cancer tissue after radiotherapy is more frequent than those without radiotherapy.It may be the potential reason for increased resection rate and sphincter-saving after radiotherapy.

Objective To construct a recombinant expression vector for expression of the function-al domains of dengue virus serotype 1 ( DENV1 ) envelope ( E ) protein in native soluble form. Methods The genes encoding the functional domains of DENV1-E protein (1-394 aa) were amplified with PCR and then cloned into the Psectag2B-Fc eukaryotic expression vector.The 293T cells were transfected with the recombinant vector by cationic lipid-based delivery.The cell clones expressing the fusion DENV1-E-Fc protein were screened out with 2 mg/ml of Zeocin.Immunofluorescence assay ( IFA) was performed to analyze the antigenicity and integrity of the fusion protein.The fusion proteins were purified from cell lysate with Protein-G and further identified by Western blot assay.Results The soluble form of fusion protein with a molecular weight of about 90×103 was obtained at a yield of about 25 μg per 1×107 cells.The results of IFA indicated that the fusion protein kept its integrity with right conformational epitopes.The fusion protein was successfully expressed with the advantage of good specificity as indicated by IFA and Western blot assay. Conclusion The recombinant fusion protein in soluble form was successfully expressed in eukaryotic ex-pression system, which paved the way for further investigation on the function of DENV1 E protein and its protective epitopes.

The chromatographic fingerprint was established by eluting with the mobile phase consisted of acetonitrile and 0.2% formic acid water on an Agilent TC-C18 (2) column (4.6 mm x 250 mm, 5 microm). Six chromatographic peaks were identified by HPLC-MS/MS method. Ten batches of Glycyrrhizea Radix et Rhizoma Praeparata Cum Melle were determined, and the similarity was arranged from 0.72 to 0.99. Good precision, stability and repeatability were obtained, and this study provides a reference for the quality control of Glycyrrhizea Radix et Rhizoma Praeparata Cum Melle.
China ; Chromatography, High Pressure Liquid ; methods ; Drugs, Chinese Herbal ; chemistry ; Glycyrrhiza uralensis ; chemistry ; Mass Spectrometry ; Quality Control ; Rhizome ; chemistry