BACKGROUND:Silk fibroin has excel ent biocompatibility, biodegradability and unique mechanical properties. Its composite, silk fibroin/nano-hydroxyapatite, can simulate the composition and structure of nature bone tissue, contributing to remedying the insufficient mechanical properties of nano-hydroxyapatites. OBJECTIVE:To observe the biological safety of silk fibroin/nano-hydroxyapatite composites. METHODS:Silk fibroin/nano-hydroxyapetite composite biomaterial was synthesized by the coprecipitation method using silk fibroin, calcium chloride and diammonium phosphate as raw materials. According to the demands of International Standard Organization (ISO10993) and Technical Evaluation Standards of Biomedical Materials and Medical Instruments promulgated by Chinese Board of Health (GB/T 16886), experiments of cel toxicity in vitro, acute toxicity and hemolysis were investigated to evaluate the biocompatibility of silk fibroin/nano-hydroxyapetite composite. RESULTS AND CONCLUSION:L929 cel s co-cultured with silk fibroin/nano-hydroxyapatite composite leaching liquor had good cel morphology, metabolism and proliferation. The leaching extract of silk fibroin/nano-hydroxyapatite composite injected into mice intraperitoneal y had no significant adverse reactions. And silk fibroin/nano-hydroxyapatite composite extracts caused 2.39%blood hemolysis, less than the international standards 5%. These experimental results on cel toxicity test in vitro, acute toxicity and hemolysis met the demands of ISO10993 and GB/T, which show the biological safety of the silk fibroin/nano-hydroxyapatite composite for clinical application.

Approximately 20 percent patients with symptomatic lumbar spinal instability, most of which occurs due to symptomatic degenerative lumbar spinal instability, trauma, tumor, and isthmus cleft, have no well results after expectant treatments. So they eventually receive reconstruction treatment to achieve thorough decompression and rebuilding of lumbar spinal stability. There are various kinds of treatments, and each of them has specific features. Therefore, the internal fixation and fusion methods should be selected according to patient condition to improve fusion rate, shorten bed staying duration and reduce complications. This paper summarized indications and features of each kind of operation as well as techniques of the interbody fusion.

Objective To explore the effectiveness of modified Sundaresans method, including exposure through the incision involving both of the sternoclavicular joint and lower cervical region with sternum retention, in the treatment for upper thoracic spinal tumor. Methods From January 1999 to October 2003, 14 patients, 9 males and 5 females, aged from 26 to 65 years with a mean of 43 years underwent the modified Sundaresans procedure. The anterior cervico-thoracic incision was made, the medial part of clavicle close to the sternoclavicular joint was removed. After the exposure of the tumor, the involved vertebral body and contiguous discs were resected, the spinal cord was decompressed, then followed by implanting part of resected clavicle or titanium mesh with an anterior locking plate system. Neurological status was graded according to Frankel grading system. Results The duration of follow-up ranged from 6 months to 2 years with an average of 10 months. This approach displayed the upper thoracic region clearly for removal of the tumor and internal fixation,in avoiding the neurological injury. All patients had their neurological improvement at different level. According to Frankel grading system, one patient improved from grade A pre-operation to B post-operation, while another patient from B to D. Of 2 cases with grade C before operation, one improved to D and the other to E. Of 4 patients with grade D, 2 improved to E, while the other 2 left unchanged. There were 6 cases keeping the same grade before and after operation. Resection of sternoclavicular joint almost had no effect on the movement of shoulder. The abduction of the shoulder joint in 14 patients from 90?-130?(average, 125?) preoperatively became 80?-120?(average, 110?) postoperatively. Conclusion The modified Sundaresans method for the upper thoracic tumors has many advantages, such as satisfactory outcome, less invasion and no loss of the shoulder function. It is especially indicated to the tumors, where the spinal compression is located anteriorly.

[Objective]To evaluate the long-term results of recurrent lumbar disc herniation between different kinds of reoperation.[Method]Seventy-four patients of recurrent lumbar disc herniation after discectomy alone were treated surgically from May 2001 to Augest 2005.They were divided into three groups:nonfusion,posterolateral fusion and intervertebral fusion.After a long term follow-up(≥2y),their clinical data were reviewed to compared their improvement rate of lower back pain,JOA score,subside rate of disc height and chang rate of superior intervertebral space angle.[Result]The long-term results revealed that the improvement rates of lower back pain JOA score in the three groups were increased in sequence.The differences in subside rate of disc height and change rate of superior intervertebral space angle between discectomy and posterolateral fusion groups were insignificant,but much higher than those of posterior lumbar interbody fusion group.[Conclusion]Posterior lumbar interbody fusion is effective in increasing the improvement rates of lower back pain JOA score and maintaining the disc height and the superior intervertebral space angle.

Objective To investigate the association between single nucleotide polymorphism (SNP) of interleukin-12 (IL-12) p40 3'untranslated region rs3212227 site and hepatitis C virus (HCV) infection. Methods Patients with hepatitis C (n=127) were genotyped and analyzed for the SNP of IL-12 p40 rs3212227 using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) and DNA sequencing. The serum HCV RNA levels of patients with hepatitis C were detected using real time fluorescence quantitative-polymerase chain reaction (FQPCR). Inter-group comparisons of genotype and allele frequency were analyzed using chi-square test.Results In patients with hepatitis C, the frequencies of AA, AC and CC genotypes of IL-12 p40 rs3212227 site were 34. 6% ,40. 9% and 24. 4% , respectively,and the frequencies of allele A, C of IL12 p40 rs3212227 site were 55.1% and 44. 9%, respectively. The frequency of rs3212227 C allele in patients with HCV RNA ≥2. 0× 106 copy/mL was higher than that in patients with HCV RNA <2. 0 ×106 copy/mL (χ2 =7. 367, P = 0. 007). The frequency of rs3212227 C allele in responders to interferon (IFN) therapy was lower than that in patients with nonresponse to IFN therapy (χ2 =4. 942,P=0. 026). Conclusions The SNP of rs3212227 is correlated with HCV infection. The carriers with C allele may be susceptible to HCV infection, while resistant to IFN therapy.

Objective To discuss the effect of applying evidence-based medicine (EBM) in orthopedic clinical teaching for eight-year program medical students in military medical university. Methods Totally 50 eight-year medical students in Shanghai Changzheng Hospital were equally divided into two groups:experimental group(EBM teaching group) and control group. The teacher of experimental group selected appropriate cases and set up the questions according to the difficulties encountered in clinical situation. Students retrieved the relevant medical literature and found out the most useful information for EBM system analysis. The results combined with the current cases were discussed. The teachers summarized clinical experiences and data according to the relevant depart-ment. Traditional direct infusion teaching mode was used in control group. Clinical work experiences were used to guide the students . After-department examination was conducted for both group after finishing the internship and questionnaire investigation was made among students in experiment group. Statistical analysis was carried out on the examination results with SPSS 17.0 software. Mea-surement data were expressed as x±s and comparison on mean differences between two groups was analyzed by t test. Results Average scores of subjective topic and military related topic in the theory exam were higher in experimental group than in traditional teaching group, with statistically significant differences(P<0.001). Excellent rate was 80%(20/25) in case discussion in experimental group and 60%(15/25) in control group. Experimental investigation questionnaire showed that: students got enhanced in learning initiative and broadened knowledge. 96%(24/25) students strengthened the learn-ing efficiency of military related chapters. 88%(22/25) students accepted this method and expected to continue. Conclusions Using the method of evidence-based medicine in eight-year program medical students in military medical university can cultivate the spirit of the stu-dents' self-study actively and rigorous earnest attitude. Students can grasp learning methods and sci-entific thinking. It also can strengthen students' awareness of military medicine and research.

BACKGROUND:Ligamentum flavum hypertrophy is one of the most important factors of lumbar spinal stenosis, but the molecular mechanism is stil not very clear. OBJECTIVE:To explore the role of basic fibroblast growth factor, connective tissue growth factor and transforming growth factor β1 in hypertrophy of the lumbar ligamentum flavum. METHODS: The ligamentum flavum samples were divided into three groups according to different diseases: control group (acquired from the patients with lumbar spinal canal tumor,n=6), lumbar disc herniation (LDH) group (acquired from the patients with LDH,n=6) and lumbar spinal stenosis (LSS) group (acquired from the patients with LSS,n=6). Then the mRNA expressions of basic fibroblast growth factor, connective tissue growth factor, transforming growth factor β1 and colagen I, III, V of the ligamentum flavum were detected using real-time quantitative RT-PCR method. The roles of basic fibroblast growth factor, connective tissue growth factor and transforming growth factor β1 were explored. RESULTS AND CONCLUSION:The expression of basic fibroblast growth factor mRNA in the LSS group was significantly higher than that in the LDH and control groups (bothP < 0.05); the expression of connective tissue growth factor mRNA was not found statisticaly different among the three groups, although it was slightly higher in the LSS group (P> 0.05); the expression of transforming growth factor β1 mRNA was significantly higher in the LSS group than in the LDH and control groups (bothP < 0.01). The colagen I mRNA expressed significantly higher in the LSS group than the LDH and control groups (bothP < 0.05), but both the colagen III and V mRNA showed no significant difference among the three groups (P> 0.05). This study indicate that both basic fibroblast growth factor and transforming growth factor β1 play important roles in the formation process of the lumbar ligamentum flavum hypertrophy, and the main type of the colagen in the hypertrophied ligamentum flavum is colagen I.

Objective:To investigate the changes of macular region structure before and after operation in patients with macular epiretinal membrane,and its relationship with the visual function of patients.Methods:The clinical data of 60 patients with macular epiretinal membrane (60 eyes) in our hospital from February 2014 to August 2016 were retrospectively analyzed.All patients were examined with optical coherence tomography (OCT) examination,and observed the changes ofmacula central fovea and retinal each azimuth thickness,and the best corrected visual acuity (BCVA) was recorded before and after operation,and the correlations of them were analysised.Results:The visual acuity was improved in 53 patients (53 eyes) after operation,accounting for 88.33％,and the visual acuity was unchanged in 7 patients (7 eyes),accounting for 11.67％.The preoperative BCVA of patients was (0.18± 0.07),and it was (0.38± 0.12) at 3 months after operation,which was significantly higher than before operation (P＜0.05).Postoperative macular central thickness,inner side of the inner ring thickness,nasal side of the inner ring thickness,above the inner ring thickness,below the inner ring thickness,outer ringtemporal side thickness,external ring nasal side thickness,above the outer ring thickness,below the outer ring thickness in patients compared with the preoperative were significantly lower,the difference was statistically significant (P＜0.05).The Pearson correlation analysis showed that preoperative macular central thickness,preoperative inner side of the inner ring thickness,preoperative outer ring temporal side thickness,the difference of macular fovea thickness before and after operation,the difference of the medial temporal before and after operationwas,the difference of outer ring temporal side before and after operation were negatively correlated with postoperative BCVA (P＜0.05).Conclusion:Vitrectomy can significantly reduce macular retinal thickness in patients with macular epiretinal membrane,and it can improve the visual function of patients,and the shape ofmacular region before operation had some influence on postoperative visual acuity.

Objective To explore the ultrasonographic features of yolk sac tumors of ovary.Methods Totally 12 patients (13 lesions) of the yolk sac tumors of ovary confirmed by pathology were analyzed retrospectively.Two-dimensional ultra sonography,color Doppler and spectral Doppler features were observed and combined with clinical manifestations.Results Ultrasound showed 1 case with bilateral single lesion and 11 cases with unilateral single lesion,the median size of tumors was 11.82 cm × 11.19 cm.Thirteen lesions showed liquid-solid mixed echo,and the blood flows in solid region were ≥ grade Ⅱ according to Adlefs semi quantitative method,the resistance index of blood was 0.37 0.55;Six cases combined with abdominal cavity effusion.Pathology showed 2 cases combined with omentum or rectal pouch metastasis and 1 case was tubal,ovarian artery and vein invasion.Conclusion Ultrasound images in the yolk sac tumors of ovary have characteristics and diagnosis must closely combine with clinical manifestations,some cases still need to be confirmed by pathology and immunohistochemist r y.

Titanium alloy has been used widely in fields of hard tissue replacement and repair,despite its characteristics of bio-inert material.Bio-ceramic coating deposited on Ti-based implants surface using surface modification technique can improve the bioactivity and biocompatibility of Ti-alloy material.The hydroxyapatite coating has been applied in clinic treatment,but this type of coating is still plagued with low crystallinity and poor bonding strength.In order to obtain an implant with excellent integrated properties,some novel bio-ceramic coating materials have been prepared.These materials having excellent bioactivity and biocompatibility and can directly bond with the Ti-based implants and the bone tissue.This review will present research status of the application of bio-ceramic coating on titanium alloy surface in biomedical fields