This paper discusses the problem of the periods of Medical Ethics. The writers suggest that Medical Ethics should be distingwished three periods: Medical Ethics, Biomedical Ethics and Bioethics.

[Objective] To explore the possible interest of therapeutic approaches including nitrogen-containing biphosphonate zoledronic acid using osteosarcoma cell lines MG63,and to investigate whether there is a synergism between zoledronic acid and methotrexate.[Method]Zoledronic acid alone or combined with methotrexate was used to treat human ostoesarcoma cells line MG63.The cell growth inhibition was assessed by MTT.[Result]There was a dose-dependent and time-dependent(1-100?mol/L)inhibition of cell proliferation by zoledronic acid.IC50 value of zoledronic acid for therapy of MG63 after 72h was 9.39 ?mol/L.The cell growth inhibition rates of MG63 at 72 h was 48.95% in zoledronic acid(10 ?mol/L)group,and 37.68%,45.93% and 52.42% in methotrexate groups MTX(1,10 and 100 mg/L).When combined treatment of zoledronic acid(10?mol/L)and methotrexate(1,10 and 100 mg/L)was used,the cell growth inhibition rates were 51.96%,66.77% and 69.23%,respectively.The combination of zoledronic acid and methotrexate demonstrated a synergistic effect.The differences were significant(P

100 d),and the histological grade of rejection was significantly lower than that in group Ⅱ(P

AIM: To investigate the effect of mycophenolate acid(MPA) on hepatitis B virus(HBV) replication in vitro.METHODS: In the presence or absence of guanosine,the HepG2.2.15 cells were treated with different concentrations of MPA(1-20 mg/L) for 4 days.Hepatitis B surface antigen(HBsAg) and hepatitis Be antigen(HBeAg) in supernatant were detected by ELISA.Intracellular HBV core mRNA and HBV DNA were analyzed by reverse transcription-polymerase chain reaction(RT-PCR) and slot blot hybridization,respectively.RESULTS: MPA suppressed the expression of HBsAg and HBeAg,and inhibited the replication of HBV DNA.The effect of MPA on HBV replication was reversed by addition of exogenous guanosine.CONCLUSION: MPA suppresses the expression of HBsAg,HBeAg and replication of HBV DNA in HepG2.2.15 cells.Reducing the synthesis of guanosine nucleotides may be involved in the mechanism of the inhibitory activity of MPA on HBV replication.

AIM: To investigate the possible role of nuclear transcription factor kappa B (NF-?B), Bcl-2, Bax and caspase-3 in etodolac-induced apoptosis of liver tumor SMMC7721 cell line. METHODS: Cell apoptosis was determined by flow cytometry analysis with PI staining and DNA laddering. Expression of Bcl-2 and Bax protein was measured by Western blotting. Caspase-3 activity was evaluated by active caspase-3 apoptosis kit with flow cytometry. NF-?B activation was detected by ELISA-based TransAM~(TM) NF-?B p65/p50 kit. RESULTS: Etodolac, a selective COX-2 inhibitor, stimulated apoptosis in liver tumor SMMC7721 cell line significantly. Flow cytometry showed that the apoptotic rate was 16.3%?3.1%, 19.9%?3.6%, 22.9%?3.2%, 31.2%?3.3% with different concentrations of etodolac (0.25, 0.50, 1.0 or 2.0 mmol/L), while the apoptotic peak did not appear in the control group (0 mmol/L) (P

AIM: To investigate lymphotactin (Lptn) gene transcription during acute cardiac allograft rejection and the inhibitory effect of cyclosporine A (CsA). METHODS: Graft specimens were harvested at indicated time to determine morphological changes by pathological examination. The grade of acute cardiac allograft rejection was evaluated by using modified Banff scoring system. Reverse transcription-polymerase chain reaction (RT-PCR) was used to determine the Lptn mRNA expression in cardiac grafts. NFATc1 activity of splenocytes after transplantation was assessed by enzyme-linked immunoabsordent assay (ELISA). RESULTS: Prominent splenomegaly on day 3 posttransplantation was found in C57BL/6-Balb/c group. The extent of myocardial inflammatory infiltration was scored 2.667?0.577 at day 5 and 2.333?0.577 at day 7, respectively. Splenomegaly was ameliorated by CsA treatment, and the extent of myocardial infiltrate was scored 1.000?0.000 at day 5 and 1.333?0.577 at day 7, respectively. Lymphotactin mRNA was undetectable in cardiac isografts. Lymphotactin mRNA, which was inhibited partially by CsA, was upregulated strongly in acutely rejecting cardiac allografts at day 5 and day 7. Further studies demonstrated that NFATc1 activity in splenocytes, which markedly upregulated during acute rejection, was completely inhibited by CsA. CONCLUSION: Lptn appears to be a key chemokine of lymphocyte infiltration during acute allograft rejection. Inhibition of NFATc1 activity by CsA seems to decrease Lptn expression incompletely, suggesting that there was else mechanism to regulate Lptn expression other than NFAT pathway.

AIM: To evaluate the effects of NS-398, a cyclooxygenase-2(COX-2) inhibitor, on the proliferation and apoptosis in HepG2 cells. METHODS: The effects of NS-398 on the proliferation of HepG2 cells was evaluated by MTT. DNA fragmentation gel analysis was used to analyze the apoptotic cells; DNA ploidy and apoptotic cell percentage were examined by flow cytometry. Furthermore, the expression of COX-2 and Bcl-2 mRNA was identified by competitive RT-PCR. RESULTS: NS-398 inhibited cell proliferation and induced apoptosis in HepG2 in a concentration-dependent manner. DNA ploidy analysis showed that S phase cells were significantly decreased with NS-398 concentration increasing. The quiescent G_0/G_1 phase was accumulated with decreasing of Bcl-2 mRNA. Whereas NS-398 had no effect on the expression of COX-2 mRNA, no correlations were found between COX-2 mRNA and the HepG2 cell proliferation and apoptosis induced by NS-398 (r=0.056 and r=0.119, respectively). CONCLUSION: NS-398 significantly inhibits the proliferation and induces apoptosis in HepG2. Mechanisms may be involved in accumulation of quiescent G_0/G_1 phase and decrease in Bcl-2 mRNA expression, but independent to COX-2 mRNA expression. [

AIM: To investigate whether viable apoptotic cells and phagocytosis of them affect the activation of T lymphocytes. METHODS: Ultraviolet irradiation was used to induce apoptotic cells in vitro and the model of phagocytosis of these cells was established. Cytokine TGF ?1 was detected by ELISA. The rate of apoptotic cells and phagocytosis of them were assessed by flow cytometry. Furthermore, flow cytometry was also employed to examine the expression of activation signs, such as CD69, CD25, CD71, of T lymphocytes under the intervention of apoptotic cells and macrophage which ingested apoptotic cells, to reflect whether the apoptotic cells and the phagocytosis of these cells could influence the activation of lymphocytes stimulated by Con A. RESULTS: Ingestion of apoptotic cells increased TGF ?1 secretion. Only the macrophages that had ingested apoptotic cells could suppress the activation of lymphocytes. The expression of the markers of lymphocytes activation such as CD69, CD25, CD71 had been restrained. These inhibition effects were abolished by monoclonal anti-TGF ?1 antibody. CONCLUSION: The macrophages that have ingested apoptotic cells inhibit expression of CD69, CD25 and CD71 of T lymphocytes stimulated by ConA. This effect is dependent on the increase in TGF ?1 secretion in local site. [

AIM: To evaluate the effects of lactacystin (LAC) and ?-lactacystin (?-LAC), proteasome inhibitor, on the proliferation and activation of T lymphocytes. METHODS: Flow cytometry was used to analyse the proliferation and the expression of CD69, CD25 and CD3 in PHA activated T-lymphocytes. Furthermore, the expression of PA28 and IL-2 mRNA were assayed by competitive RT-PCR. RESULTS: (1) LAC and ?-LAC significantly decreased the incorporation in PHA activated T-lymphocytes. (2) Although LAC and ?-LAC did not affect the expression of CD69 at any time, they significantly inhibited the expression of CD25 (48 h, 72 h, P

AIM:To explore the effect of the pretreatment of hypertonic saline(HTS) in hepatic ischemia reperfusion(I/R) injury.METHODS:The rats were divided into sham group(sham group),ischemia reperfusion group(IR group) and pretreatment of hypertonic saline group(HTS group).Partial hepatic ischemia reperfusion model was used.The rats were sacrificed at the time of 1 h,3 h,6 h,12 h and 24 h after reperfusion in each group,respectively.Blood samples were obtained to examine ALT.The expression of the CD11b/CD18(Mac-1) on the neutrophils was analyzed by flow cytometry.RT-PCR and Western blotting were used to examine the expression of intercellular adhesion molecule-1(ICAM-1) in livers and chromatometry was performed to detect the activity of myeloperoxidase(MPO) in livers.The morphology of hepatocytes and the structure of sinusoid were observed by histological examinations.RESULTS:① HTS pretreatment decreased the level of ALT at the time points of 3 h,6 h and 12 h after reperfusion(P