We have reformed our patterns and methods of graduation examination of the medical majors. That is the multi-stage comprehensive graduation examination of the clinical interns, which consists of 70% close written test of clinical theories,20% practical test of clinical skills and also oral test of related theories, and 10% writing of the medical documents. It has proved that these measures have improved the interns' attitude toward practice, aroused their initiative and positivity, and led the practitioners to attach more importance to the combination of clinical practice and theories, thus leading to better clinical education.

Objective To investigate the effects of interlukin-10 (IL-10) on lipopolysaccharide (LPS)-induced liver injury in rats.Methods One hundred male Wistar rats,aged 10-14 weeks,weighing 250-300 g,were randomly divided into 5 groups (n =20 each):control group (C group),LPS group,IL-10 group,HO-1 inducer cobalt protoporphyrin-Ⅸ group (Co group) and HO-1 inhibitor zinc protoporphyrin-Ⅸ group (Zn group).The animals in LPS,IL-10,Co and Zn groups received intraperitoneal LPS 20 mg/kg.IL-10,Co and Zn groups received recombinant human IL-10 1 μg at 3 h before LPS injection.Co and Zn groups received cobalt protoporphyrin-Ⅸ and zinc protoporphyrin-Ⅸ 25 mg/kg at 2 h before administration of recombinant human IL-10.Ten rats in each group were chosen at 24 h after LPS injection and blood samples were collected from the heart for determination of the levels of serum alanine aminotransferase (ALT),aspartate transaminase (AST),tumor necrosis factor-α (TNF-α) and interlukin-1β (IL-1 β).The animals were then sacrificed and lungs removed for determination of glutathione peroxidase (GSH-Px) and superoxide dismutase (SOD) activities,malonodialdehyde (MDA) content and expression of HO-1 mRNA in lung tissues.The left 10 rats in each group were chosen and the survival rates within 72 h after LPS administration were recorded.Results Compared with C group,the levels of serum ALT,AST,TNF-αand IL-1 β and MDA content in lung tissues were significantly increased,and GSH-Px and SOD activities in lung tissues and survival rates were decreased in LPS,IL-10,Co and Zn groups (P ＜ 0.05).Compared with LPS group,the levels of serum ALT,AST,TNF-α,IL-1β and MDA content in lung tissues were significantly decreased,GSH-Px and SOD activities in lung tissues and survival rates were increased,and the expression of HO-1 mRNA was up-regulated (P ＜ 0.05).Compared with IL-10 group,the levels of serum ALT,AST,TNF-α and IL-1β and MDA content in lung tissues were significantly increased,and GSH-Px and SOD activities in lung tissues and survival rates were decreased in group Zn (P ＜ 0.05),and no significant change in the parameters mentioned above was found in Co group (P ＞ 0.05).Conclusion IL-10 can attenuate LPS-induced liver injury in rats by inducing the expression of HO-1.

The interaction of drug and target protein is a critical part of new drug discovery. It is the premise for drugs to exert therapeutic effects by targeting specific binding sites of target proteins and thereby affecting its pharmacological activity. Currently, a variety of techniques are exploited to detect the interaction between drug ligands and target proteins. For example, cellular thermal shift assay (CETSA) and differential scanning fluorimetry (DSF) based on thermodynamics, mass spectrometry and nuclear magnetic resonance technology, etc. In addition, high-throughput ligand screening technology provides technical convenience for the search of specific ligand, and is a powerful tool to efficiently identify the interaction between drug ligand and target protein. Here, we summarize the detection techniques of interaction between small molecules and target proteins, and discuss the application of high-throughput ligand screening technology in drug research.

Target identification and verification of natural products is an important and challenging work in the field of chemical biology. It is also an important job for researchers to apply chemical proteomics technology to biomedicine in order to identify target proteins of natural products. Target identification is critical to understanding its mechanisms and developing natural products as molecular probes and potential therapeutic drugs. Traditional approaches of small molecule target identification based on affinity have been shown to be successful, such as click-chemical probes, radioisotope labeling or photosensitized small-molecule probes. Nevertheless, these technologies require purified candidate target proteins, and modified small molecules with probes or linkers, such as adding agarose beads, biotin labels, fluorescent labeling or photo-affinity labeling. Many structure-activity relationship studies should be performed to ensure that the addition of small molecule labels undisturbed the original biological activity of the small molecules. Unfortunately, all these modifications are likely to alter their biological activity or binding specificity. To overcome the bottleneck of "target recognition", researchers have developed a series of new techniques for unmodified drug target identification. In this article, we reviewed the target identification techniques of natural product without structural modification in order to provide reference for the development of natural products.

Objective To synthesize antimicrobial bioceramic using chitosan and calcium phosphate cements mixed with ceftriaxone sodium. Methods The bioceramic was synthesized through the hardening of chitosan liquid combined with calcium phosphate cements and cefiriaxone sodium.The released ceftriaxone sodium was studied according to the linear equation between UV-VIS absorbance to concentration.The in vitro bactefiostatic effect of the chosen bioceramic was investigated via the microbiological method.The model of rats'contaminated bone defect were deployed to study the antimicrobial performance of the bioceramic. Results The best synthesis condition was chosen at:0.1g calcium phosphate cements and 10.4 mg ceftriaxone sodium combined with 2.4 ml hardening liquid C.then keeping the mixture at 60℃ and 100%humidity for 24 h.In vitro release of the resulting antimicrobial bioceramic remained stable,while that of ceftriaxone sodium lasted for a week,higher than the minimal inhibitory concentration(MIC) of Staphylococcus aureus.As proved by the WBC number and tissue sectioning,a lighter inflammatory response of treatment group was observed as compared with the control group. Conclusion The antimicrobial bioceramic combined with chitosan and ceftriaxone sodium shows promising antimicrobial performance.

OBJECTIVETo study the radiosensitizing effect of resveratrol on hypopharyngeal carcinoma cell line FADU in vitro.

METHODSHypopharyngeal carcinoma cell line FADU was cultured in in vitro DMEM. Its inhibition on cell proliferation was detected using cytotoxicity test (MTT assay). The cell survival curve was drawn using clone formation to obtain sensitive enhancement ratio (SER). Changes of the cell cycle and cell apoptosis were analyzed using flow cytometry (FCM).

RESULTSResults of MTT showed the inhibition of resveratrol on FADU cells increased along with its concentrations (P < 0.05). Results of clone formation indicated the surviving fraction at 2 Gy (SF2) was 0.717 ± 0.062 in the irradiation group, and 0.426 ± 0.035 in the resveratrol plus irradiation group (with SER ranged 1.684 ± 0.178) with statistical difference (P = 0.007). Results of FCM showed that after radiation of 4 Gy radiation, cells at G2/M phase arrest increased, but cells at G1 decreased. After radiation of resveratrol for 24 h, cells at G1 decreased, but cells at G2/M phase and S phase arrest increased. When 4 Gy radiation combined resveratrol was used, cells at G2/M phase arrest significantly increased, but cells at G1 significantly decreased. The apoptosis rate was 1.94% ± 1.65% in the control group, 4.56% ± 0.92% in the irradiation group, 2.03% ± 1.46% in the resveratrol group, and 23.11% ± 7.22% in the resveratrol plus irradiation group. There was statistical difference between the resveratrol plus irradiation group and the rest 3 groups (P < 0.05).

CONCLUSIONResveratrol could enhance the radiosensitivity of hypopharyngeal carcinoma FADU cells in vitro possibly by inducing cell apoptosis and causing changes in the cell cycle distribution.

Apoptosis ; Carcinoma, Squamous Cell ; Cell Cycle ; drug effects ; Cell Line, Tumor ; Cell Proliferation ; Cell Survival ; Head and Neck Neoplasms ; Humans ; Hypopharyngeal Neoplasms ; drug therapy ; Radiation Tolerance ; Radiation-Sensitizing Agents ; therapeutic use ; Stilbenes ; therapeutic use

Objective To investigate the relationship between surfactant associated protein-A(SP-A) in bronchoalveolar lavage fluid(BLAF) and lung function in children with refractory mycoplasma pneumoniae pneumonia(RMPP).Methods Thirty children with RMPP were selected from January 2015 to December 2016 in the People's Hospital of Hebi City.The partial pressure of oxygen in artery (PaO2),partial pressure of carbon dioxide in artery (PaCO2),forced expiratory volume in one second(FEV1) and forced vital capacity (FVC) of the children were detected at acute and convalescent periods.The BALF was collected by bronchoalveolar lavage,and the level of SP-A in BALF was detected by enzyme linked immunosorbent assay.Results The level of SP-A in BALF of children with RMPP at ac ute and convalescent period was (3.63 ± 0.09) and (5.86 ± 0.17)mg · L-1 respectively,the level of SP-A in BALF of children with RMPP at acute phase was significantly lower than that at convalescent period(t =-63.499,P ＜ 0.05).The PaO2 and PaCO2 in children with RMPP at acute phase were (49.25 ±7.32) and (47.16 ±6.48)mmHg respectively,and they were (76.54 ±6.48) and (36.20 ± 5.61)mmHg respectively at convalescent period;the PaO2 in children with RMPP at acute phase was significantly lower than that at convalescent period (t =-15.289,P ＜ 0.05),and the PaO2 in children with RMPP at acute phase was significantly higher than that at convalescent period(t =7.004,P ＜ 0.05).The FEV1,FVC and FEV1/FVC in RMPP children at acute phase were (1.36 ±0.67),(1.68 ± 0.31) L and 69.85 ± 8.34 respectively;and they were (1.89 ± 0.58),(1.99 ± 0.53) L and 87.32 ± 9.52 respectively at convalescent period;the FEV1,FVC and FEV1/FVC in RMPP children at acute phase were significantly lower than those at convalescent period(t =-3.276,-2.765,-7.560;P ＜ 0.05).The level of SP-A in BALF of children with RMPP was positively correlated with PaO2 (r =0.921 6,P ＜ 0.05),but there was no significant correlation between SP-A level and PaCO2 (r =1.211 4,P ＜ 0.05).The level of SP-A in BALF was positively correlated with FEV1,FVC and FEV1/FVC (r =0.831,0.905,0.803;P ＜ 0.05).Conclusion The level of SP-A in BALF was positively correlated with lung function of children with RMPP.The detection of SP-A level in BALF is helpful to assess the lung function and pathogenetic condition of children with RMPP.

Objective To investigate the clinical significance of the expression of pulmonary surfactant associated pro-tein(SP)in bronchoalveolar lavage fluid(BALF)of children with refractory Mycoplasma pneumoniae pneumonia(RMPP). Methods Thirty children with RMPP were selected from January 2015 to December 2016 in the People's Hospital of Hebi City. The lung function of the children was detected in acute and recovery stage,and bronchoalveolar lavage was performed with fiexible bronchofiberscope. The BALF was collected,and the levels of SP-A,SP-B,SP-C and SP-D in BALF were detected by enzyme linked immunosorbent assay. Results The forced expiratory volume in one second (FEV 1 ),forced vital capacity (FVC)and FEV1 / FVC in RMPP children at acute stage were (1. 34 ± 0. 23)L,(1. 75 ± 0. 28)L and (68. 25 ± 6. 21)％respectively;and they were (1. 71 ± 0. 35)L,(1. 98 ± 0. 36)L and (88. 57 ± 8. 16)％ respectively in the children at recov-ery stage. The FEV1 ,FVC and FEV 1 / FVC in RMPP children at recovery stage were significantly higher than those in the chil-dren at acute stage (t = 4. 839,3. 070,14. 859;P < 0. 05). The levels of SP-A,SP-B,SP-C and SP-D in the RMPP children at acute stage were (50. 19 ± 10. 06),(42. 95 ± 12. 42),(36. 81 ± 8. 14)and (21. 57 ± 5. 46)μg·L - 1 respectively;and they were (135. 20 ± 18. 13),(108. 42 ± 20. 33),(142. 63 ± 21. 87)and (72. 69 ± 8. 54)μg·L - 1 respectively in the children at recovery stage. The levels of SP-A,SP-B,SP-C and SP-D in BALF of RMPP children at recovery stage were significantly higher than those in the children at acute stage (t = 22. 457,15. 052,24. 837,27. 623;P < 0. 05). Conclusion The detection of SP-A,SP-B,SP-C and SP-D levels in BALF plays a guiding role in the diagnosis,disease assessment,treatment and prognosis judgment of RMPP.

Aim To develop the in vitro and in vivo models induced by shrimp tropomyosin( ST) and mono-clonal tropomyosin-specific murine IgE antibody ( anti-ST-IgE mAb) . Methods ST was purified from Metap-enaeusensis by an isoelectric precipitation method. The anti-ST-IgE mAb was obtained from hybridomas. After RBL-2 H3 cells were sensitized with anti-ST-IgE mAb and challenged with ST,β-hexosaminidase release was determined. Passive systemic anaphylaxis ( PSA ) was induced in mice and the rectal temperature was recor-ded after ST challenge within 30 min by a thermal probe. Results A significant increase ofβ-hexosamin-idase was observed in sensitized cells after ST chal-lenge. The average temperature drop after ST challenge was 1. 44℃ in PSA mice within 30 min. Conclusion The in vitro and in vivo models induced by ST and anti-ST-IgE mAb are established as an improvement of pres-ent models of type Ⅰ allergy.

Objective:To develop murine models of Th2 response induced by shrimp tropomyosin (ST). Methods:Mice were sensitized with ST for 6 weeks. The serum antigen-special IgE (sIgE),total IgE and sIgG level,Th1/Th2 cytokines production were measured by ELISA. The basophil activation in mice was measured by flow cytometry. Results:The intraperitoneal sensitization with ST for 6 weeks induced significant increase of serum sIgE,total IgE and sIgG (sIgG1,sIgG2a and sIgG2b) level in mice. Th2 cell response was induced and cytokines (IL-4,IL-5,IL-10 and IL-13) production increased in splenocytes stimulated by ST,while Th1 cytokine (IFN-γ) production decreased. As the markers of basophil activation,CD200R and CD41 expression also increased in response to ST. Conclusion:The Th2 response is dominant in ST-induced anaphylaxis in mice.