Ginsenoside Rh2 induced human colorectal cancer cell apoptosis through PI3K/AKT/GSK-3βpathway / 中国药理学通报

Aim To investigate the effect of Ginsen-oside Rh2 on apoptosis in human colorectal cancer cell SW480,and to explore the possible mechanism of it. Methods The proliferation activity of SW480 treated with Ginsenoside Rh2 was measured CCK-8 assay.Ap-optosis rates were evaluated by FCM.Hoechst 33258 staining was used to observe cell nucleus morphologi-cal;change SW480 cells were treated with Ginsenoside Rh2,and the protein expressions of Bcl-2,Bax,p53, cleaved caspase-3 ,PI3 K,AKT,P-AKT,GSK-3β,P-GSK-3βwere detected by Western blot;SW480 cells were treated with LY294002,Rh2,LY294002+Rh2, the expressions of PI3 K,AKT,P-AKT,GSK-3β,P-GSK-3βwere detected by Western blot.Results The proliferation of SW480 cells was significantly inhibited by Ginsenoside Rh2 in dose-dependent and time-de-pendent manner.FCM showed the inducing apoptosis effect of Ginsenoside Rh2 was significantly different from that of control group.Hoechst 33258 staining in-dicated clearly cell apoptosis in Ginsenoside Rh2 treat-ment groups.Western blot showed Ginsenoside Rh2 decreased expression of Bcl-2,increased expression of Bax,p53 and cleaved caspase-3,PI3K/AKT/GSK-3βpathway proteins PI3 K,P-AKT,P-GSK-3βdecreased obviously,AKT and GSK-3βwere not changed signifi-cantly in SW480.SW480 cells were separately treated with LY294002,Rh2,LY294002 +Rh2,there were no significant difference in AKT and GSK-3βprotein a-mong all groups,and the expression of PI3 K,P-AKT, P-GSK-3βdecreased more obviously in LY294002 +Rh2 group compared with LY294002 and Rh2 alone. Conclusion Rh2 induces colorectal cancer cell apop-tosis through PI3 K/AKT/GSK-3βpathway,which ac-tivates p53 and cleaved caspase-3,and destroys the balance of Bcl-2/Bax.

Study on present situation and strategy study on graduate students' scientific ethics and academic atmosphere of 10 colleges and universities in Chongqing / 重庆医学

Objective To understand the academic atmosphere current situation of graduate students and put forward relevant countermeasures to protect the academic integrity of graduate students.Methods The graduate student'scientific ethics and academic atmosphere construction situation of graduate students in 10 colleges and universities in Chongqing were investigated by questionnaire survey and analyzed.Results Through 1555 questionnaires,it was found that the average investment of time on scientific research in gruduate students was insufficient,the motivation of learning was complicated,and the situation of preventing academic misconduct was serious.Conclusion This study suggests that colleges and universities should establish an academic integrity security system for graduate students,including establishment of academic integrity system and specializing academic integrity supervision institutions,and strengthing academic integrity education.

Ribonucleic acid Ⅱ induces apoptosis in human leukemia cells by up-regulating p53 / 中国药理学通报

Aim To investigate the effect of ribonucleic acidⅡon apoptosis in human leukemia cell lines K562 and KG1 a.Methods Cell counting kit-8(CCK-8)as-say was performed to detect proliferation activity of K562 and KG1 a cells treated with ribonucleic acidⅡ. Apoptosis index was assessed by flow cytometry(FCM) and fluorescent Hoechst 33258 staining was used for observing morphologic changes of apoptosis.Expres-sion levels of p53,Bax,Bcl-2 and cleaved caspase-3 were analyzed by Western blot.Results The prolifera-tion of K562 and KG1 a cells was significantly inhibited by ribonucleic acid Ⅱ treatment for 12 h,24 h,48 h at concentrations of 100~300 mg·L-1 ,which indica-ted the inhibitory effect of ribonucleic acid Ⅱ was in dose-dependent and time-dependent manners.FCM re-sults displayed a dose-dependent increase in cell apop-totic rate.Hoechst 33258 staining showed the typical apoptotic morphology in some leukemic cells treated with ribonucleic acid Ⅱ,including increased nuclear chromatin concentration and edge accumulation.West-ern blot analysis showed the increased expression of p53,Bax,cleaved caspase-3 and decreased expression of Bcl-2 in K562 and KG1 a cells treated with ribonu-cleic acid Ⅱ.Conclusions Ribonucleic acid Ⅱ can induce apoptosis of leukemia K562 and KG1 a cells by up-regulating p53,which mediates Bcl-2/Bax balance and activates caspase-3 .

Rh2 weaken effects ofβ-catenin on HepG2 hepatocellular carcinoma through ac-tivating Gsk-3β / 中国免疫学杂志

Objective: To investigate the inhibitory effect of Rh2 on HepG2 cells and explore the underlying mechanism.Methods: We used lentivirus carrying β-catenin to infect HepG2 cell, and detected expression of β-catenin using fluorescence microscopy.The effect of Rh2 on proliferation of HepG2-β-catenin and HepG2 cells was measured by CKK-8 assay,and flow cytometry was used to detect cell cycle and apoptosis.The activity of Gsk-3βwas checked by ELISA kit.The expression of Gsk-3β,β-catenin,Bax,Bcl2,CyclinD1,MMP3 genes were measured by qRT-PCR.In order to checked the relationship between β-catenin and TCF4,CHIP assay kit was used,the expression of Bax,Bcl2,CyclinD1,MMP3 genes were measured by PCR.The expressions of Gsk-3β,β-catenin,Bax,Bcl2,CyclinD1,MMP3 proteins were examined by Western blot.Results:HepG2 cells were successfully infected by pLOV-EF1a-MCS-3FLAG-β-catenin lentivirus,named HepG2-β-catenin.CCK-8 showed that ginsenoside Rh2 could effectively inhibit the proliferation of HepG2 and HepG2-β-catenin cells in vitro,which exhibits a dose-dependent manner at range of 10-160 μmol/L Rh2.The IC50 of Rh2 exposure on HepG2 cell for 48,72 h were 100 μmol/L and 58.12 μmol/L,but the IC50 of Rh2 exposure on HepG2-β-catenin for 48,72 h were 129.2 μmol/L,83.33 μmol/L,respectively.The IC50 of Rh2 exposure on HepG2-β-catenin cell was higher than HepG2 cell, compared with HepG2 group the differences was statistically significant ( P<0.01 ).Flow cytometry indicated that Rh2 could arrest HepG2 and HepG2-β-catenin cells in G0/G1 phase;the cell population in G0/G1 phase of HepG2+Rh2 group was(64.57±0.65)%,HepG2-β-catenin+Rh2 group was(58.61±2.01)%.Flow cytometry indicated that Rh2 could induced early apoptosis in HepG2 and HepG2-β-catenin cells.The apoptosis rate of HepG2 +Rh2 group was (17.27 ±2.77)%,HepG2-β-catenin +Rh2 group(9.02 ±1.76)%.The ELISA results indicated that HepG2 cells was induced by Rh2 for 12,24,48,72 h,the activity of Gsk-3βgradually increased,peak in 48 h,then decreased.Compared with control group,Rh2 induced HepG2 and HepG2-β-catenin cells for 48 hours, Gsk-3βactivity were increased, and their activity reduced after adding Bio, there were no significant differences between HepG2+Rh2 and HepG2-β-catenin+Rh2 groups.The PCR,CHIP and WB results showed that the expression of Gsk-3β,Bax gene and proteins increased,while theβ-catenin,CyclinD1,Bcl2,MMP3 gene and proteins down-regulation in HepG2 and HepG2-β-catenin cell induced by Rh2.Compared with HepG2-β-catenin +Rh2 group, the expression of other gene and proteins changed significantly,however,Gsk-3βwas no significant difference.Conclusion:Over-expression of β-catenin may weaken the phar-macological effects of ginsenoside Rh2 on HepG2 cells.The activity of Gsk-3βwas increased by ginsenoside Rh2 to degradeβ-catenin, affecting the expression of downstream genes,promoting apoptosis of liver cancer cells and inhibiting metastasis.

Mechanism of ginsenoside Rh2 inhibiting HepG2 cells migration / 中国免疫学杂志

Objective:To study the mechanism of ginsenoside Rh2 inhibiting HepG2 cells migration.Methods:HepG2 cells in logarithmic growth phase were cultured in 96-well plates,which were induced by different concentration Rh2,respectively for 24,48,72 hours.The cell inhibition was detected by Cell Counting Kit.Transwell chambers was used to checked HepG2 cell migration ability;luciferase was tested by Luciferase Reporter Assay system reagent;The expressions of P-ERK,ERK,P-P38,P-38,P-JUK,JUK,MMP3 proteins were detect by Western blot;the expression of AP1,MMP3 gene were detected by Quantitative PCR;The expression of AP1, MMP3 fluorescence protein were observed by fluorescence microscopy.Results:Administrated with different concentration of Rh2 after 24 ,48 ,72 h,the proliferation of HepG2 cells were inhibited ( P<0.05) ,and in dose-and time-dependent manner.Transwell assay showed Rh2 could significantly inhibited migration of HepG2 cells.The expressions of P-ERK , MMP3 proteins were significantly decreased,the expressions of P-JUK, P-P38 proteins were significantly increased, expression levels of ERK, P-38, JUK were no significant difference.Expression of AP1,MMP3 gene were significantly decreased,the expressions of AP1,MMP3 fluorescence proteins were significantly decreased.Conclusion:Ginsenoside Rh2 can activate MAPK pathway to inhibit the migration of HepG2 cells.

Integration on postgraduate cultivation model in biomedical engineering based on ‘combination of production-teaching-research, interdisciplinary of medicine-science-engineering, international horizon exploration’ / 中华医学教育探索杂志

This paper discussed on the innovative efforts of establishing production-teaching-research platform and multi-channel international cooperation model by Chongqing Medical University. Measures taken included offering theoretical courses across the first-level disciplines of medicine and engineering and encouraging research tasks that involve the cooperation among hospitals , businesses and universities, creating education environment for postgraduates combing medicine and engineering and launching the cultivation of biomedical engineering postgraduates. The aim of these measures was to incorporate the achievements of scientific research innovation into postgraduate education and to improve its quality.

Study on postgraduate tutor assessment system in medical colleges / 中华医学教育探索杂志

Objective To explore the postgraduate tutor assessment system in order to provide suggestions to improve the quality of postgraduate education. Methods Assessment indexes of post-graduate tutor were screened and assigned by methods of questionnaire investigation, interview, kruskal wallis H-test, taking a total of 109 students and professors in medical colleges in the south-western part as research objects. Results Different populations had different cognitions on the important degree of each index, P<0.05. Primary indexes of assessment system were determined based on the importance of indicators and the influence of different cognitive levels, including tutor personal accom-plishment, teaching ability, scientific research quality and guiding ability (P<0.05). Conclusions Assessment system and method fined by this study covers majority aspects of tutors and can provide feasible suggestions for tutor evaluation.

Inhibitory effect of trichostatin A on HepG2 cell proliferation and the mechanisms / 南方医科大学学报

<p><b>OBJECTIVE</b>To investigate the inhibitory effect of trichostatin A (TSA) on the proliferation of HepG2 cells and explore the underlying mechanism.</p><p><b>METHODS</b>HepG2 cells exposed to different concentrations of TSA for 24, 48, or 72 h were examined for cell growth inhibition using a cell counting kit, changes in cell cycle distribution with flow cytometry, cell apoptosis with annexin V-FTIC/PI double staining, and cell morphology changes under inverted microscope. The expressions of beta-catenin, HDAC1, HDAC3, H3K9, cyclinD1 and Bax proteins in the exposed cells were detected by Western blotting, and the expressions of HDAC1 and HDAC3 mRNAs by quantitative fluorescent PCR.</p><p><b>RESULTS</b>Exposure to TSA caused significant dose- and time-dependent inhibition of HepG2 cell proliferation (P<0.05) and resulted in increased cell percentage in G0/G1 and G2/M phases and decreased cell percentage in S phase. The apoptotic index in the control group was (6.22 ± 0.25)%, which increased to (7.17 ± 0.20)% and (18.14 ± 0.42)% after exposure to 250 and 500 nmol/L TSA, respectively. Exposure to 250 and 500 nmol/L TSA also caused cell morphology changes with numerous floating cells. The expressions of beta-catenin, H3K9 and Bax proteins were significantly increased and CyclinD1, HDAC1, and HDAC3 protein expressions decreased in TSA-treated cells, but the expressions of HDAC1 and HDAC3 mRNAs showed no significant changes.</p><p><b>CONCLUSIONS</b>TSA can inhibit the proliferation of HepG2 cells and induce cell cycle arrest and apoptosis by inhibiting HDAC activity, promoting histone acetylation, and activating Wnt/beta-catenin signaling pathway.</p>

Research on causes and countermeasures for postgraduate academic misconduct in University / 中华医学教育探索杂志

In recent years, problem of postgraduate academic misconduct has become more and more serious and has caused the attention of majority of educators and academics. In this paper , the con-notation of postgraduate academic misconduct was defined based on academic standards and comparison was made between academic misconduct and academic corruption. Meanwhile , this paper pointed out problems existed in the current postgraduate academic ethnic construction and analyzed main causes of academic misconduct. Finally, this paper introduced the success experiences of Chongqing Medical Uni-versity in preventing postgraduate academic misconduct from the aspects of system construction , propa-ganda and education, supervision in postgraduate training process, strict control of graduate thesis,etc.

Reform and practice of medical postgraduate curriculum system / 中华医学教育探索杂志

Curriculum study is a major phase for medical postgraduate education,however,the patterns of the curriculum system are not uniform among domestic medical colleges,not to mention the uniformed patterns for scientific degree and professional degree.Hence,our school has reformed the curriculum system to set up different curriculum systems for both scientific degree and professional degree according to their different educational goals in an aim to improve the quality of education.

On the effects of strengthening the construction of supervisor team on improve the quality of postgraduate education / 中华医学教育探索杂志

Strengthening the construction of supervisor team has great effects on the improvement of the quality of postgraduate education.Some problems exist in China's current situation of the construction of supervisor team.For example,the quality of supervisors needs to be improved,the quantitative evaluation system is not scientific,the quantity of professional degree supervisors is not enough,and the dynamic evaluation mechanism is imperfect and so on.Strengthening the construction of supervisor team from the development of scientific and rational quantitative evaluation index system,the selection of professional degree supervisors,the enhancement of supervisor training and some other aspects,can effectively improve the quality of postgraduate education.

The common problems and solution of graduate education in cilinical medicine professional degree / 中华医学教育探索杂志

With the size of graduate education continues to expand,deepening the reform of graduate education to improve the quality of graduate education has become the core of graduate education.This paper introduces the common problems and solution of graduate education in cilinical medicine professional degree.

Practice of the standardized management of graduate students' experimental records / 中华医学教育探索杂志

It introduced the standardized management of graduate students' experimental records. On the basis of experimental records standardization, 3 level inspection system including tutors, departments and graduate school plays a very important role in setting up the good habit, getting more reliable experimental results and preventing the happening of misconduct in scientific research.

The thinking of graduate medical education of integrity / 中华医学教育探索杂志

Integrity education is not only one of an important aspect of moral education topics for Medical postgraduates,but also an objective requirement in the socialist market economy.Aiming at the modern medical postgraduates'lack of credibility,this paper mainly analyzes its causes such as the limitation of postgraduates'quality and the pressure of employment and dis-cusses how to strengthen integrity education for postgraduate in medical university by bringing supervisors'leading role,enhance the standardized management of employment and upbuilding credibility file etc.

Double Blind Appraisement——the Important Measure to Promote the Doctor Degree Thesis Quality / 中华医学教育探索杂志

The important sign of scaling graduate culture quality is the quality of doctor degree papers.By strengthening the doctor degree management and carrying out the system of outside university experts' double blind judge,the doctor degree papers can be appraised scientifically,reasonably,impersonally and justly so as to achieve the aim of promoting the quality of doctor degree thesis.

Problems and Countermeasures of the Cultivation of Postgraduates in Clinical Medicine / 中华医学教育探索杂志

The clinic ability training is the important tache of cultivating postgraduates with the degree of clinical medicine and the clinic ability training's quality control is the important issue.This paper analyzed the existent problems in cultivation at present and expatiated the steps and countermeasure we ought to adopt in light of the actual condition of our university.

Effects of TSPG combined with EPO or GM-CSF on differentiation of K562 cells / 第三军医大学学报

Objective To investigate the effects of total saponins of Panax ginseng(TSPG) combined with erythropoietin(EPO) or granulocyte macrophage colony stimulating factor(GM CSF) on the differentiation of K562 cells. Methods Cells were cultured in vitro . Morphologic changes of cells were observed with light microscope and electron microscope. The levels of hemoglobin, peroxidase, non specific lipase ? NAE in cells were detected respectively by benzidine staining, peroxidase(POX) staining and ? NAE cytochemical staining. Levels of cell surface differentiation antigens CD15, HIR2, EPO R and GM CSF R were determined by immunocytochemistry. Results TSPG combined with EPO or GM CSF resulted in more mature morphological features of K562, increased expressions of hemoglobin and myeolperoxidase in K562 cells, and enhanced expressions of cell surface differentiation antigens CD15, HIR2, EPO R and GM CSF R. Conclusion TSPG combined with cytokine EPO or GM CSF can induce more mature differentiation of K562 cells.

Analysis and Evaluation of the Test Paper for Histology and Embryology / 中华医学教育探索杂志

We analyzed the final test papers for Histology and Embryology among the seven-year program students from 2000 to 2004 in our university to evaluate the quality of the test paper and teaching effects so as to find the weaknesses and problems in teaching.The results showed that the test papers were reliable because of comprehensive test items,moderate difficulty and reasonable score distribution,and the score could image the level of students in truth.But the gap between good scores and bad scores is rather obvious,Teachers must help the students who have difficulties in learning Histology and Embryology and shorten the gap in the future.

Fixed Quantity Comment on the Doctoral Candidates′ Theses / 中华医学教育探索杂志

We analyzed the result of the fixed quantity comments on 160 doctoral theses of our university in recent 4 years. The result indicates that the total level of the doctoral theses is relatively good , but there are few excellent theses. The doctoral candidates have substantial basic theory and fine quality foe research, but they can rarely bring forth new ideas and they lack writing ability. Aiming at these problems, we put forward 8 item suggestions to promote fostering working and continuously improve the doctoral candidates' training quality.

Experimental study on effect of apoptosis of K562 cells treated with TSPG / 中草药

Object To clarify the mechanism for total saponins of Panax ginseng C.A.Mey. (TSPG) inducing K562 cells to apoptosis, and to provide the theoretical basis and the experimental evidence of TSPG's clinical application. Methods By using in vitro cell culture, morphometry, flow cytometry, morphological investigation and immunocytochemistry, the effects of TSPG on apoptosis in K562 cells were studied. Results The results indicated that TSPG could inhibit the proliferation of K562 cells significantly, and induce K562 cells to apoptosis. It was also showed in the experiments that after induced by TSPG, the ratio of positive K562 cells expressing C-MYC and BCL-2 is decreased. Conclusion The mechanism for TSPG to induce K562 cells to apoptosis may be related to the expression of oncogene in K562 cells.