Decellularized tissues and organs have been widely used in tissue engineering and regenerative medicine applications. The efficiency of cell removal from a tissue depends on the origin of the tissue and the methods applied. Each of these treatment affects the biochemical composition, tissue ultrastructure, and mechanical behavior of the remaining scaffold, which in turn, affect the host response to the material. Herein, we made a review about the most commonly used decellularization methods and their effects upon biologic scaffolds.

Objective To analyze the survival statistics and perioperative parameters of clinical stage Ⅰ non-small cell lung cancer patients who received systemic or selective mediastinal lymphadenectomy,and explore the value of selective mediastinal lymphadenectomy for clinical stage Ⅰ non-small cell lung cancer.Methods The clinical data of 984 patients with clinical stage Ⅰ non-small cell lung cancer who underwent lobectomy and systemic/selective lymph node dissection in Zhongshan Hospital from January 2005 to December 2010 were analyzed retrospectively.There were 581 males and 403 females with an average age of(59.6 ± 10.2) (24-84) years.786 patients received systemic mediastinal lymphadenectomy,and 198 patients received selective mediastinal lymphadenectomy.Results Average operation time of selective mediastinal lymphadenectomy group was(132.3 ±30.3) minutes,and that of systemic mediastinal lymphadenectomy group was(150.7 ±41.8) minutes with significant difference(P ＜ 0.01).Average amount of intraoperative bleeding of selective mediastinal lymphadenectomy group was (96.2 ± 53.5) ml,and that of systemic mediastinal lymphadenectomy group was (124.4 ± 65.4) ml with significant difference(P ＜0.01).There was no significant difference in overall survival rate between two groups(P =0.844).Recurrence rates were 25.3 ％ and 27.5 ％,respectively (P =0.533).Subgroup analysis showed no significant difference of 5-year survival rates between the two groups.Conclusion For patients with clinical stage Ⅰ non-small cell lung cancer,selective mediastinal lymphadenectomy can reduce operation time and amount of intraoperative bleeding.Survival of patients who received selective mediastinal lymphadenectomy was no worse than that of patients who received systemic mediastinal lymphadenectomy.

Anthrax is a fulminating infectious disease .Bacillus anthracis, as the pathogen of anthrax , is a potential ma-terial for biological warfare agents and biological terrors .Immunoprophylaxis and specific theraphies play key roles in cop-ing with anthrax threats.Researches on the mechanism of B.anthracis infection, especially the process of infection , can fa-cilitate the development of novel drugs for anthrax prevention and therapy .Herein, by reviewing research progress , the in-fection process of B.anthracis is introduced and the potential mechanism of anthrax infection is described .Furthermore, the relationship between researches on anthrax infection mechanisms and the development of drugs for anthrax prevention and therapy is also discussed .

Objective To observe and analyse the application effect and value of problem based learning (PBL) combined evidence-based learning (EBL) in emergency medicine clinical teaching.Methods A total of 53 clinical medicine students were selected.The combined teaching method was applied in emergency clinical teaching.After the end of the teaching,the teaching effectiveness survey and theory test of the combined teaching group was performed,and the theory test scores was compared with the traditional teaching group.Results The combined teaching method could stimulate learning enthusiasm,improve learning efficiency,the abilities of selfstudy,literature retrieval,and the ability to analyze and solve problems.77.4％ of students thought this new teaching method had good application value in clinical teaching.Furthermore,the excellent rate of the theory test scores combined teaching group was better than traditional teaching group (41.5％ vs 15.6％,x2 =7.868,P =0.007).Conclusions The PBL joint EBL pedagogy can overcome diadvantages of tradional teaching and provide higher interest,ability of self-study as well as higher teaching quality of the medical students.It will be worth to spread in medical clinical teaching.

0.05)in sex,age and volume of lesions.Over a course of treatment the average volume of thyroid adenomas of each group significantly(P

Recently the research of vaccines and drugs against anthrax is one of hot spots. The efficacy of anthrax vaccines and drugs can't be experimented in human, therefore the testing model is very important. The cell models mainly include CHO and J774A.1. Now, various kinds of animals including mice, rats, rabbits, and nonhuman primates were experimented as animal models. Because the models are different, the results of experiments are significantly different, sometimes they are contrary. Many experiments of Bacillus anthracis in different cell and animal models are reviewed, and the principles of choosing animal models of anthrax are discussed. In order to analyze the different results of experiments in different models, the pathogenesis of Bacillus anthracis and the researching progress of anthrax vaccines and drugs are also simply introduced .

The RD-1 locus has been considered crucial in the pathogenesis of M.tuberculosis, the RD-1 locus is 9.5 kb and spanning open reading frames Rv3871 to Rv3879c encoding 9 different proteins separately.The RD-1 locus is missing in all bacillus Calmette-Guerin(BCG) strains, and is one of the key virulence factor in M.tuberculosis.The RD-1 locus participates in a new secreting system named ESX-1, which can facilitate the secretion of some special proteins.The two important proteins encoded by the RD-1 locus named CFP-10 and ESAT-6 can form a tight 1∶1 complex, and has been shown to be coordinately secreted and lead to a strong T cell response, which suggests that these two proteins may act as ideal target antigens in diagnosis and prevention of tuberculosis(TB).

BACKGROUND:Oligo(poly(ethylene glycol)fumarate) (OPF) hydrogel is a kind of biomaterial with good biocompatibility, injectability, and biodegradability. It is known that there are differences in the characteristics of hydrogels with different molecular weights. Under osteogenic induction, bone marrow mesenchymal stem cels encapsulated in the suitable molecular weight hydrogel have better proliferation and differentiation. Therefore, the use of OPF hydrogel provides new options for bone tissue-engineered scaffold.
OBJECTIVE:To investigate the effect of OPF hydrogel with different molecular weights on the proliferation and differentiation of encapsulated rat bone marrow mesenchymal stem celsin vitro.
METHODS: Four kinds of OPF hydrogels with molecular weights of 1 000, 3 000, 10 000 and 35 000 were developed by OPF crosslinking with a redox radical initiation system. Hydrogel sweling and degradation properties were detected. Afterwards, bone marrow mesenchymal stem cels encapsulated in different hydrogels were cultured in osteogenic medium for 1-3 weeks. The effects of hydrogels on morphplogy of bone marrow mesenchymal stem cels and osteogenic differentiation were detectedvia histological staining (hematoxylin-eosin staining and alizarin red staining) and immunofluorescence staining.
RESULTS AND CONCLUSION: With the increase of molecular weight of hydrogels, the gelation time was shortened, the sweling ratio significantly increased, and the hydrogel degradation rate was proportional to the molecular weight. In addition, the number of mineralized nodules formed in 3 000 and 10 000 molecular weight hydrogels was more than that in the other hydrogels, indicating that hydrogels with appropriate sweling and degradation properties are beneficial to cel proliferation and differentiation. In conclusion, OPF hydrogels have good biocompatibility and hydrogels with 3 000 and 10 000 molecular weight play active regulatory roles in osteogenic differentiation of mesenchymal stem cels.

Objective To investigate an X-ray total body irradiation (TBI) technique using anterior-posterior opposed fields with patients at the side-lying position,and to analyze the real-time in vivo dosimetry results.Methods The accelerator with 10 MV X-rays of Varian Trilogy was used for the TBI with the extended source to skin distance of 390 cm.The percent depth dose,off axis factors and absolute dose output were measured.The dose accuracy and homogeneity was monitored real-time using multichannel diode dosimeter for 10 patients.The monitored sites included forehead,mandible,suprasternal fossae,xiphoid,umbilicus,pelvis,middle of thigh,knee,middle of leg and ankle.The patients were irradiated at the side-lying position,with the prescription dose of 1 200 cGy/6 f during 3 days,the middle line dose rate of 5.0 cGy/min.Solid water was used for the compensation of the dose homogeneity.Results The off axis dose homogeneity was less than ± 5.0％ for the TBI geometry.The absolute dose output was 0.072 1 cGy/MU at the maximum dose point.The total body irradiation was finished smoothly for the 10 patients lying on side.The deviation of monitored total dose from the total prescription dose was within -4.9％ to 6.7％ for the 10 monitored sites.The monitored dose homogeneity was less than 5.0％.Conclusions The fractionated anterior-posterior opposed parallel TBI can be finished smoothly with patients side-lying.Accurate and homogenous dose distribution can be obtained using real-time dose monitoring and compensation with solid water.

Objective To analyze the safety, feasibility and operative technique details of non-grasping en bloc mediastinal lymph nodes dissection technique in uniportal video-assisted thoracic surgery(VATS) for lung cancer.Methods From April, 2014 to March, 2015,46 patients with lung cancer received non-grasping en bloc mediastinal lymph nodes dissection after uniportal VATS lobectomy.Clinical data of the cases were analyzed retrospectively.There were 19 males and 27 females.The age was(57.2 ± 9.0) (38-73) years.The first 6 cases were performed in the lateral decubitus position while the later 40 cases were all performed in the semiprone position.Results All cases accepted uniportal VATS non-grasping en bloc mediastinal lymph nodes dissection successfully.Arm fatigue of surgeon and assistant was obviously relieved when the patient was placed in the semiprone position.The thoracic drainage time was(3.2 ± 2.1) (1-12)days and the postoperative length of hospital-stay was(6.0 ± 4.5) (2-27) days.The number of dissected mediastinal lymph nodes stations was (4.3 ± 0.8) (3-6)and the number of dissected mediastinal lymph nodes was (11.8 ± 4.9) (4-30).There were 42 cases with stage No , lease wit stage N1, and 3 cases with stage N2 in pathological examination.Five patients developed minor postoperative complications.No perioperative death occurred.Conclusion Uniportal VATS non-grasping en bloc mediastinal lymph nodes dissection for lung cancer was safe and feasible, which could decrease the interference of the instruments and help to keep the surgical field clear.Non-grasping en bloc mediastinal lymph nodes dissection would be performed more smoothly in the semiprone position with less damage to lung and better ergonomics.