Colorectal cancer (CRC) is one of the most common digestive system neoplasms in China. Recently, the morbidity and mortality rates of CRC continue to increase with the improvement of people's living standard and the change of the dietary structure. It was accepted that the etiology of colorectal cancer is a multi-factor and multi-step process. However, the mechanism of CRC is still unclear. MicroRNAs (miRNAs) are a class of -21 nucleotide non-coding RNAs and function as a negative regulator of gene expression after transcription, participating in tumor angiogenesis, tumor cell proliferation and invasion. MicroRNA-21 (miR-21), as an important oncogenic RNA, plays a vital role in the development and progression of CRC. This review summarizes the advances in research on miR-21 in colorectal cancer.

Objective:To investigate the present situation of medical students′medical ethics education and fur-ther to put forward countermeasures for medical colleges and universities. Method:With the methods of question-naire, literature and interview, medical students of the second grade and above in Xi′an Jiaotong University, Xin-jiang University and Xinjiang Medical University were investigated. SPSS 20. 0 was used to establish a database and frequency analysis method was used to analyze data. Results:It is suggested that some medical students′ motiva-tion to be a doctor is pure and the professional ethical identity is correct. There exist problems in the evaluation of ethics anomie behaviors. The students lack of cognition of medical ethics but pay more attention to medical technol-ogy. Most of the medical students think that clinical practice education and the model demonstration of teachers are conducive to medical ethics education. Conclusion: Universities can develop their own medical ethics education mode through various forms of classroom education, the involvement of old professors in teaching, strengthening learning of medical laws, daily ideological education by counselors and the construction of campus spiritual civiliza-tion.

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Objective To investigate the effect of running exercise on cartilage in rats with an unstable knee joint.Methods Twenty 8-week-old Sprague-Dawley rats had their left anterior cruciate ligament cut to model an unstable knee.They were randomly divided into a control group and an experimental group,10 rats in each group.The control group was given no intervention,while the experimental group accepted running exercise training on na animal treadmill at a velocity of 15 m/min for an hour every day.After 3 and 6 weeks of training,5 rats were sacrificed and cartilage from the medial condyle of the femur was sampled,decalcificated,embedded and sliced on the sagittal plane.After hematoxylin-eosin staining,toluidine blue staining and immunohistochemical staining,the cartilage thickness,Mankin' score,the content of matrix collagen and the proteoglycan content of the cartilage matrix were assessed,and the shape and structure of the unstable knee joints were observed under a transmission electron microscope.Results The cartilage thicknesses and Mankin's scores at 6 weeks were significantly different from those at 3 weeks in both groups.In the experimental group the average thickness of cartilage was 154 ± 13 μm at 3 weeks and 131 ± 15 μm at 6 weeks.The corresponding Mankin's scores were 9.93 ± 1.36 and 11.23 ± 1.57,respectively.Both were significantly different from the control group averages at the same time points.There was also a significant difference in the positive rate of toluidine blue and collagen type Ⅱ staining between the experimental group and the control group at both time points,and in the experimental group between 3 and 6 weeks of training.After 3 weeks of training,fewer chondrocytes were observed under the transmission electron microscope in the experimental group,and fissures were seen on the surface of the cartilages.However,3 weeks later,quite a few ruptures and a lot of necrotic cells could be seen.Conclusions Running exercise can damage the cartilage of unstable knee joints and speed up the development of osteoarthritis.Even moderate exercise could aggravate damage to unstable joints and the cartilage matrix,and accelerate chondrocyte degeneration.

Objective To prepare the solid dispersion of ginsenoside Rg3 with different carriers and measure their solubility and dissolution characterisitics. Methods The solid dispersion of ginsenoside Rg3 was prepared by the melted and dissolved methods with Poloxamer 188(F68), PVP k29/32, and PEG 6000 as carriers, respectively. The equilibrium solubility and dissolution characteristics of the solid dispersion in vitro were measured by HPLC. The existing state of ginsenoside Rg3 in the solid dispersion was identified by the differential scanning calorimetery. Results The ginsenoside Rg3 was completely dispersed in carrier and formed a mixture with carriers. The solubility and dissolution rates of all solid dispersion were increased obviously. Conclusion The solid dispersion of ginsenoside Rg3 with Poloxamer 188 as carriers is better on improving dissolution and solubility than those with PVP and PEG 6000 as carriers.

Objectives To establish a reliable method for isolating and purifying soluble collagen type Ⅱ(SCⅡ)by optimizing preparative procedure.Method The chicken sternal cartilage was selected as raw material.Guanidine hydrochloride was used to remove the proteoglycans.The digestion manners of pepsin,sodium chloride concentrations for salting,types of DEAE anion resin were studied for extracting SCⅡ.The SCⅡ identification was made by SDS-PAGE,absorption spectrum and amino acid analysis.Result It was convenient for pre-treatments of chicken sternal cartilage.The proteoglycans could be efficiently removed by 4 mol/L guanidine hydrochloride.The satisfied results were obtained by limited enzyme digestion of pepsin added by two steps.The optimizing concentration of sodium chloride for salting was 2.4mol/L.SDS-PAGE maps revealed that the bands of purified SCⅡand standard CⅡ were at the same location.The absorption peak of SCⅡ was at 230nm.The concentrations of Gly,Pro and Ala were the highest in 15 amino acids.Conclusion The improved method has significant advantages of simple working process,result reliability and convenient source of raw material.It is suitable for purifying the SCⅡ at variable scales in research works and clinic application.The SCⅡ product obtained has high purity and accords with the characteristics of collagen type Ⅱ.

Objective: To study the changes of andrographolides in the drying process of the extract of Andrographis paniculata Nees. Methods: HPLC method was applied to analyze andrographolide and 14 deoxy 11, 12 didehydroandrographolide in the process. Results: The content of andrographolide descended rapidly in the whole drying process, while the content of 14 deoxy 11, 12 didehydroandrographolide ascended at first 12 hours, declined in content was slowly to follow. Conclusion: Baking temperature is not the only main factor to stimulate the transformation of andrographolide and 14 deoxy 11, 12 didehydroandrographolide.

To study the chemical constituents of Drynariae Rhizoma, nine phenolic acids were isolated from a 70% ethanol extract by using a combination of various chromatographic techniques including column chromatography over silica gel, ODS, Sephadex LH-20, and semi-preparative HPLC. By spectroscopic techniques including 1H NMR, 13C NMR, 2D NMR, and HR-ESI-MS, these compounds were identified as 4, 4'-dihydroxy-3, 3'-imino-di-benzoic acid (1), protocatechuic acid (2), gallic acid (3), p-hydroxybenzoic acid (4), (E)-caffeic acid (5), ethyl trans-3, 4-dihydroxycinnamate (6), caffeic acid 4-O-beta-D-glucopyranoside (7), p-coumaric acid 4-O-beta-D-glucopyranoside (8), and 23(S)-12-O-caffeoyl-12-hydroxyllauric acid glycerol ester (9), separately. Among them, 1 and 9 are new compounds, and 3, 4, and 6 were isolated from Drynaria species for the first time.

ObjectiveTo investigate the influence of cobalt chloride ( CoCl2 )-mimetic hypoxia on theproliferation,apoptosis and migration of human pancreatic cancer cell fine PANC1.MethodsPANC1 cells were treated with 0(control),100,200,400,800 μmol/L CoCl2 respectively for 24 h.Real-time RT-PCR and Western blot were used to determine hypoxia induced factor ( HIF)-1o mRNA and protein expression respectively,and cell counting kit-8(CCK-8) assays,flow cytometry and cell scratch test were used to examine the proliferation,apoptosis and migration of PANC1 cells,respectively.ResultsIn the control group and 100,200,400 and 800 μmol/L CoCl-2 groups,the expressions of HIF-1t mRNA were 1,1.08 ±0.12,1.12 ± 0.09,1.04±0.11,0.66 ±0.07,and the expressions of VEGF mRNA were 1,2.69±0.35,4.81 ±0.54,2.19 ± 0.21,0.79 ± 0.08,while the expressions of HIF-1 α protein were 0.23 ± 0.03,0.36 ± 0.04,1.15 ± 0.11,1.08 ± 0.09,0.44 ± 0.04; and the expressions of VEGF protein were 0.14 ± 0.02,0.12 ± 0.01,0.95 ±0.09,0.87 ±0.09,0.55 ±0.06; and cell viability rates were 100％,(98.43 ±2.88)％,(76.15 ± 0.70)％,(53.87 ±0.77)％,(35.23 ±0.67)％ ; while cell apoptotic rates were (5.2 ±1.12)％,(5.74 ± 1.07)％,(6.82 ± 1.85)％,(12.09 ±3.53)％,(31.88 ±6.95)％ ; the cell migration distance of PANC1 cells were (43.24 ±3.67)％,(59.46 ±5.39)％,(80.56 ±8.05)％,(63.89 ±5.96)％,(9.09 ± 1.59 ) ％.Compared with those of control group,the expressions of VEGF mRNA,VEGF and HIF-1 α protein,cell migration distance showed a two-way variation ( ascending first and descending later) (P ＜0.05 ),and the expression of HIF-1α mRNA and cell proliferation rate was decreased in a dose-dependent manner,while the cell apoptosis was increased in a dose-dependent manner.Conclusions CoCl2 significantly inhibits the proliferation and promotes apoptosis of PANC1 cells at certain level.CoCl2 has a two-way effect on the migration of PANC1 cells,and it may be related to the direct injury of high concentration of CoCl2 on cells.

Objective To discuss effect of fasting and taking food on hemostasis effect of patients with gastric ulcer and bleeding. Methods 160 patients with gastric ulcer and bleeding were divided in-to the experimental group and the control group, the experimental group was allowed to take lower ho-moiothermy water gruel (liquid), the control group was required absolute fasting (not medication), until bleeding stop. The two groups adopted identical treatment and nursing. The lienable stomach tube was placed respectively, everyday pH value monitor and occult blood test were carried out by taking out gas-tric juice when fasting and 2 hours after meals. Continuous monitoring tests continued till occult blood test of gastric liquid became negative for 3 times. Stool was kept for occult blood test, at the same time the gastrointestinal tract symptom and bleeding condition were observed, routine blood test was carried out one every other day. The data underwent statistical analysis with SPSS13.0 statistics software package, compari-son between two groups used t test. Results The inner stomach pH value of the experimental group in-creased obviously, the average pH value and percentage of pH above 4 was evidently higher than those of the control group. The time of occult blood test of gastric liquid and stool turning to negative in the experi-mental group was shorter than those of the control group. Conclusions Taking food can elevate pH of gastric liquid, reduce damage caused by gastric acid to gastric mucosa, thus hasten hemostasis process and promote healing.