BACKGROUND:Polyvinyl alcohol is a biocompatible and biodegradable polymer. It is widely used in clinical areas because of its water-soluble, film forming, emulsification, adhesiveness, tasteless, and nontoxic.
OBJECTIVE:To review the applications of polyvinyl alcohol and its composite materials in bone, cartilage, skin, vessels and other tissue engineering scaffolds.
METHODS:A computer-based online search of CNKI database from January 2000 to December 2011, PubMed database and Elsevier (ScienceDirect) database from January 1980 to December 2012, was performed by the first author with key words of“poly(vinyl alcohol), composite material, tissue engineering scaffold”both in Chinese and English. Literatures concerning polyvinyl alcohol and its composite materials in bone, cartilage, skin, vessels and other tissue engineering scaffolds were included, and repetitive research was excluded.
RESULTS AND CONCLUSION:Although there are not enough strength, complications and other shortcomings in vivo, due to its good biocompatibility and biodegradable properties, polyvinyl alcohol and its composite
materials have made great progress in tissue engineering applications from the laboratory to the pre-clinical
research. But its long-term effects need further research. It wil be a main research aim of scaffold materials in the future to improve the interaction of cel s with the scaffold materials by surface modification, to prepare biomimetic materials by cel microenvironment simulation, to improve the hydrophilicity, the adhesion of cel s, and cel
differentiation and proliferation, to bionic the structure and function of the natural extracel ular matrix by building three-dimensional porous structure and control ing the release of cel growth factors, to meet the need of tissue regeneration by congruity or harmony of degradation and mechanical strength.

Objective:To observe the interventative effect of Ziyin-Huatan Decoction by regulating exosomes on subcutaneous tumor of mice with gastric cancer. Methods:MGC-803 cells were randomly divided into exosome control group, low-dose group and high-dose group. The low-dose group and high-dose group were intervened with Ziyin-Huatan Decoction of 25 μg/ml and 100 μg/ml respectively. After 48 hours, the exosomes secreted by MGC-803 cells in each group were extracted. Twenty BALB/c male mice were randomly divided into exosome control group, low-dose Ziyin-Huatan Decoction group, high-dose Ziyin-Huatan Decoction group and blank control group, with 5 mice in each group. Except for the blank control group, the mice in the other groups were injected with exosomes extracted from the cells of the corresponding group through the orbit, 10 μg/time for each mouse, once every other day, a total of 15 times; the blank control group was injected with the same amount of PBS. Then SGC-7901 cells were inoculated into mice to establish a tumor model. The tumorigenic rate and body weight of mice were observed. The levels of CD31, VEGF and bFGF in tumor tissues were detected by immunohistochemistry. Results:Compared with the blank control group, the tumor weight [(170.00 ± 10.00) mg vs. (343.33 ± 20.82) mg] and the expression of CD31 (37.43 ± 0.55 vs. 63.30 ± 0.85), VEGF (11.37 ± 1.19 vs. 70.30 ± 0.72) and bFGF (43.77 ± 1.53 vs. 84.97 ± 1.86) in the high-dose Ziyin-Huatan Decoction group significantly decreased ( P<0.05). Compared with exosome control group, the expressions of CD31, VEGF and bFGF in low and high dose Ziyin-Huatan Decoction groups were decreased ( P<0.05). Conclusion:Ziyin-Huatan Decoction can significantly inhibit the growth of subcutaneous tumor of gastric cancer in mice by regulating exudation, which may be related to the inhibition of tumor angiogenesis.

BACKGROUND: Multiwaled carbon nanotubes can accelerate the proliferation and differentiation of osteoblasts, and exert a therapeutic effect on steroid-induced necrosis of femoral head (SNFH). OBJECTIVE:To investigate the function of multiwaled carbon nanotubes in the establishment of a rabbit model of SNFH. METHODS:Thirty-six New Zealand white rabbits were divided randomly into three groups. In treatment group, 16 rabbits were given intraglutealy injection of dexamethasone (2.5 mg/kg) every day and injection of 1 mL liquor of multiwaled carbon nanotubes (0.1 g/L) into the bilateral femur medulary space every week. In model group, 16 rabbits were given intraglutealy injection of dexamethasone (2.5 mg/kg) every day and injection of 1 mL normal saline into the bilateral femur medulary space every week. In control group, four rabbits were given intraglutealy injection of 2 mL normal saline every day and injection of 1 mL normal saline into the bilateral femur medulary space every week. RESULTS AND CONCLUSION: Four weeks after hormone injection, the trabeculae began to exhibit a smal amount of thinner fractures, an accumulation of fatty tissue in the bone marrow were obvious, bone marrow fat cels became bigger and microvascular thrombosis appeared in the model group, while there was no positive histopathological manifestation in the treatment group. This indicates that the multiwaled carbon nanotubes can extenuate pathological damage to the femoral head to a certain extent.

Objective To explore the medical care and evacuation equipment at sea in China.Methods The present situation of the medical care and evacuation equipment at sea in China was discussed from the aspects of equipment system,medical service support,mechanism for utilization,management and maintenance as well as informatization.The problems were analyzed in equipment system,support ability,equipment integration and update as well as equipment performances.Results Some measures were put forward from the aspects of equipment system,support ability,equipment integration and update as well as equipment performances.Conclusion The development of medical care and evacuation equipment at sea has to take considerations on medical service requirements at sea,integrated civilian and military uses,personnel,innovation and etc.

With IL-6R as target, a new compound 2460A was identified from fungus using HTS screening model. The taxonomics of the produced strain was confirmed to be Trichoderma hazianum rifai after sequencing analysis of rDNA-ITS (internal transcribed spacer). Results showed that this compound has a binding activity on IL-6R competed with IL-6, thus it is a new ligand of IL-6R originating from microbe. With MTT assay, the anti-tumor activities of 2460A were demonstrated on CM126 and HT-29 cell lines separately, the IC50 are 2.17 x 10(-5) mol x L(-1) and 1.8 x 10(-5) mol x L(-1) respectively. The compound affected lightly the HT-29 cell cycle at S phase. Studies for the anti-tumor activity of 2460A in vivo are in progress in our lab.

Objective To investigate the effect of flipped classroom based on WeChat and mi-crolecture in medical chemistry experiment course in the context of "internet". Methods The classes were randomly divided into 2 groups, experimental group (flipped classroom teaching, n=97) and the control group (traditional teaching, n=98). Comparison of the chemistry experiment test results were performed with the use of t test between the two teaching groups at the end of the semester to evaluate the experimental teaching method. All statistical processing and analyses were performed with SPSS software (version 12.0). Results The chemistry experiment test score of the experimental group was higher than that of the control group [(77.84±8.22) vs. (73.43±10.14), t=3.341, P=0.008), and the difference was statistically significant. The results of the questionnaire showed that the students in the experimental group generally consider that flipped classroom teaching is better than the traditional teaching in terms of the cultivation of comprehen-sive quality and the teaching effect. Conclusion In the context of "internet", flipped classroom teaching with WeChat microlecture can better mobilize the enthusiasm of students to learn and participate in medical chemistry experiment course, which has been welcomed by students and further suggest good application prospects.

In vitro transcription systems with T7 RNA polymerase (T7 RNAP) were widely used in preparation of RNA because of their simplicity and high efficiency. The transcripts would have additional 5' sequence since T7 promoter spans the transcription start site, while deletion of the transcription start site would severely reduce the T7 RNAP transcriptional activity. We successfully developed an in vitro transcription by combining of T7 RNAP high efficient transcription system and highly specific self-splicing technology of ribozymes, in this system, ribozyme self-splices at the designed specific site and releases the aim RNA without affecting transcription efficiency of T7 RNAP, the aminoacylation activity of human mitochondrial tRNA(Trp) (HmtRNA(Trp) (UCA)) is 113.6 pmol/microg. This method with its high efficiency on transcription and good repeatability is very suitable for preparation of accurate RNA in large scale.
Base Sequence ; DNA-Directed RNA Polymerases ; genetics ; Humans ; Molecular Sequence Data ; RNA ; genetics ; RNA Splicing ; RNA, Catalytic ; genetics ; RNA, Transfer, Trp ; genetics ; Transcription, Genetic ; Transfer RNA Aminoacylation ; genetics ; Viral Proteins ; genetics

Objective To explore the effect of Jintiange capsule on treatment of postmenopausal osteoporosis (PMOP) and its mechanism.Method 133 patients diagnosed as PMOP and meeting the standard were collected from Oct.2011 to Aug.2015 in our hospital.They were randomly divided into two groups:treatment group and the control group.The control group received calcium and alendronate,while the treatment group received 3 Jintiange capsules 3 times daily on the basis of the control group.The lumbar bone densit (BMD),greater trochanter BMD,femoral neck BMD,Ward triangle BMD,visual analogue score (VAS) of knee and back,the serum levels of bone glaprotein (BGP),alkaline phosphatase (ALP),β-C-terminal telopeptide of type Ⅰ collagen (β-CTX),N-terminal propeptide of type Ⅰ procollagen (PINP) and adverse reactions were recorded before and after treatment.Results The lumbar BMD,greater trochanter BMD,femoral neck BMD,ward triangle BMD of treatment group after treatment were higher than those before treatment and those of the control group (P＜0.05).VAS score of knee and back of treatment group were lower than those of the control group (P＜0.05).The serum levels of BGP,ALP,β-CTX,PINP of treatment group were lower than those of the control group (P＜0.05).The adverse reactions rate of two groups had no significant difference (P＞0.05).Conclusion Jintiange capsule can significantly reduce bone metabolism level,increasing BMD,reducing bone loss,relieving knee and back pain of PMOP,without increasing complication rates,which is worthy to be promoted due to high safety and efficacy.

Objective    To compare the clinical efficacy between right visual double lumen tube (VDLT) intubation and right common double lumen tube (DLT) intubation in lung isolation technique. Methods    A total of 57 patients undergoing thoracoscopic surgery with right DLT lung isolation technique in the First People's Hospital of Chenzhou City and West China Hospital from June 2020 to June 2021 were randomly divided into two groups: a DLT group (n=29, 16 males and 13 females, with a mean age of 54.3±13.2 years) and a VDLT group (n=28, 18 males and 10 females, with a mean age of 55.1±13.7 years) at 1 : 1 with random number table generated by the computer. The clinical data of the two groups were compared. Results    Compared with the DLT group, the catheter positioning time in the VDLT group was statistically shorter (74.9±47.5 s vs. 151.6±88.9 s, P<0.001), the right upper lung occlusion rate (21.4% vs. 51.7%) and the intraoperative re-adjustment catheterization rate (14.3% vs. 48.3%) were lower (P<0.05). The quality of lung collapses immediately after thoracotomy (67.9% vs. 24.1%) and 20 minutes after thoracotomy (100.0% vs. 75.9%) were improved (P<0.05). There was no significant difference in the rate of fiberoptic bronchoscope assistance for positioning, or the incidence of pharynx pain and hoarseness between the two groups (P>0.05). Conclusion    Compared  with common DLT, VDLT is more efficient, accurate and intuitive in the location of right bronchial intubation.