BACKGROUND:How to effectively promote bone regeneration and bone reconstruction after bone injury has always been a key issue in clinical bone repair research.The use of biological and degradable materials loaded with bioactive factors to treat bone defects has excellent application prospects in bone repair. OBJECTIVE:To investigate the effect of polylactic acid-glycolic acid copolymer(PLGA)composite scaffold modified by lysine-grafted graphene oxide nanoparticles(LGA-g-GO)on osteogenic differentiation and new bone formation. METHODS:PLGA was dissolved in dichloromethane and PLGA scaffold was prepared by solvent evaporation method.PLGA/GO composite scaffolds were prepared by dispersing graphene oxide uniformly in PLGA solution.LGA-g-GO nanoparticles were prepared by chemical grafting method,and the PLGA/LGA-g-GO composite scaffolds were constructed by blending LGA-g-GO nanoparticles at different mass ratios(1%,2%,and 3%)with PLGA.The micromorphology,hydrophilicity,and protein adsorption capacity of scaffolds of five groups were characterized.MC3T3 cells were inoculated on the surface of scaffolds of five groups to detect cell proliferation and osteogenic differentiation. RESULTS AND CONCLUSION:(1)The surface of PLGA scaffolds was smooth and flat under scanning electron microscope,while the surface of the other four scaffolds was rough.The surface roughness of the composite scaffolds increased with the increase of the addition of LGA-g-GO nanoparticles.The water contact angle of PLGA/LGA-g-GO(3%)composite scaffolds was lower than that of the other four groups(P<0.05).The protein adsorption capacity of PLGA/LGA-g-GO(1%,2%,and 3%)composite scaffolds was stronger than PLGA and PLGA/GO scaffolds(P<0.05).(2)CCK-8 assay showed that PLGA/LGA-g-GO(2%,3%)composite scaffold could promote the proliferation of MC3T3 cells.Alkaline phosphatase staining and alizarin red staining showed that the cell alkaline phosphatase activity in PLGA/LGA-g-GO(2%,3%)group was higher than that in the other three groups(P<0.05).The calcium deposition in the PLGA/GO and PLGA/LGA-g-GO(1%,2%,and 3%)groups was higher than that in the PLGA group(P<0.05).(3)In summary,PLGA/LGA-g-GO composite scaffold can promote the proliferation and osteogenic differentiation of osteoblasts,and is conducive to bone regeneration and bone reconstruction after bone injury.

Abstract Prevention and control of myopia requires comprehensive measures. Based on the system established earlier, the system is revised and upgraded. The original system emphasizes comprehensive measures and proposes to focus on both the symptoms and root causes. These measures are summarized into six aspects, three address the root cause measures including health education, glasses optics and visual environment, and three address symptoms measures including eye exercises, physical therapy and drugs. The paper is comprehensively supplemented and analyzes the primary and the secondary, and promotes physical therapy from treating the symptoms to treat both the symptoms and the root causes. These improvement measures will help promote the prevention and control of myopia in children and adolescents.

Objective To elucidate the protein expression and gene expression status and the relationship between epidermal growth factor receptor (EGFR) protein expression and EGFR gene status.Methods Tissue microarray containing 72 cervical squamous cell carcinoma tissues was constructed,and EGFR protein expression and gene status were evaluated by immunohistochemical and fluorescence in situ hybridization (FISH) techniques.Results Protein expression of EGFR:69 of 72 cervical squamous cell carcinomas were observed.The results demonstrated it was significant association with invasion depth,lymphnode metastasis and lymph-vessel invasion (x2 =4.998,P ＜ 0.05 ; x2 =4.299,P ＜ 0.05 ; x2 =4.686,P ＜ 0.05) in cervical squamous cell carcinomas.For FISH assessing EGFR gene,64 of 72 carcinomas were observed; 7 of 64 cases showed EGFR gene amplification,and 25 disomy,23 trisomy and 9 polysomy were detected.There were high levels of protein expression in all the EGFR gene amplification cases,and there were significant association between EGFR protein expression and the gene copy number (x2 =13.564,P ＜ 0.05).Conclusions EGFR may participate in the occurrence,progression and metastasis of cervical squamous cell carcinoma.Overexpression of EGFR protein may result from gene amplification and gene copy number increases,which showed that EGFR gene expression status may be a more effective biological indicator of cervical squamous cell carcinoma targeted therapy.

ObjectiveTo explore the clinical and pathological features of hypomyopathic dermatomyositis(HDM).MethodsSix cases of HDM among 62 cases of dermatomyositis diagnosed between January 2008 and June 2010 were collected and analyzed.Four were women and 2 were men.The age of onset was between 45 and 65 years old,with disease duration of more than 6 months.All HDM patients presented with DM-specific skin lesions,but without muscle weakness.Serum creatine kinase(CK) level was within normal limits in 5 and mild elevated in 1.Electromyogram showed myogenic changes in 4 cases and normal in the other 2 patients.Muscle biopsies were carried out in the left biceps branchii in all of them.The muscle sectionswereprocessedwithstandardhistologicalprocedures,enzymehistochemistricaland immunohistochemical stains were carried out.The antibodies used for immunohistochemical stains were antiCD8,anti-CD20,anti-CD68,and anti-MHC-Ⅰ monoclonal antibodies.ResultsMuscle biopsies showed a variable amount of macrophages and B-lymphocytes infiltrating in the peri-mysium and fascicle area.Three of them presented with mild peri-fascicular fiber atrophy with fiber necrosis and regeneration.Lipid droplets increased mildly in muscle fibers.Capillaries distributing around perifascicular regions were darkly stained in nonspecific esterase stain.Perifascicular fibers showed immune-reactivity to MHC-Ⅰantibody.Conclusion The myopathological changes of HDM mimic classical dermatomyositis in some cases.HDM might be an intermediate presentation between pure amyopathic dermatomyositis and classical dermatomyositis.

Objective To Explore the effect of Cassia Seed budding transforming organic vanadium. Methods Separate organic vanadium from inorganic vanadium in Cassia Seed sprouts by dislysis bag. The content of total vanadium and inorganic vanadium were determined by using the method of Graphite Atomic Absorption Spectrophotometry. The transformation efficiency of organic vanadium in the Cassia Seed spouts was calculated. Results The seed coat of Cassia Seed could accumulate massive inorganic vanadium existing in environment during the process of its natural growing period,but the transformation efficiency of organic vanadium mainly occurred inside seed coat of Cassia Seed. Condusion Cassia Seed budding is one pathway of the biologic organification of vanadium.

Objective To explore the determination of elements selenium content in Se Semen Cassiae. Method Selenium content in Se Semen Cassiae was measured by graphite atomic absorption spectrophotometer. Result and Conclusion An appropriate extraction method and digesting condition were screened out. The determined results were accurate when the digested sample was dissolved and metered volume with 1% HNO3 which containing 0.1% Tween 80.

AIM To determine the effect of L-arginin e on cerebral blood perfusion following subarachnoid hemorrhage(SAH) in rats. METHODS Endovascular perforating SAH models were replicated in Wista r rats, and animals were divided into sham-operated group, SAH group and SAH+ L-arginine group. Dynamic changes of regional cerebral blood flow (rCBF) with in 24 hours were measured and serum nitric oxide(NO, NO - 2/NO - 3)levels at different time points within 24 hours were detected. Mean arterial blood pre ssure and blood gas were monitored during the experiment. RESULTS No obvious change in physiological parameters in the three groups was observed . rCBF and serum nitric oxide level at every time point after operation in SAH g roup were lower than those in sham-operated group. Pathological alterations abo ve in SAH+L-arginine group were less obvious than those in SAH group. CONCLUSION L-arginine, by antagonizing the decrease of nitric oxi de, exerts protective effect on secondary cerebral ischemia following SAH.

The impairment of learning and memory function in the central nervous system(CNS)is one of the main features of aging and Alzheimer' s disease (AD). Many experimental results have showed that long- term memory(LTM) is related to long- term potentiation(LTP) and long- term depression (LTD). They intluenee each other. The relationship between LTP and LTD is complex. Therefore, it is important to study the learning and memory mechanism from LTP、LTD and gene expression in the CNS.

The purpose of the present work is to observe cGMP positive cells after cerebral ischemia-reperfusion in the gerbil hip-pocampus. Immunofluorescent methods were used in gerbil hippocampal tissue slices. The results showed that after cerebral is-chemia cGMP synthesis in the CAi-a subfields was increased, cGMP positive cells were distributed mainly in CA1 subfield. Mostof cGMP positive cells were astrocytes. The number of small round cGMP positive cells were increased after recirculation follow-ing ischemia in the dentate gyrus. These results indicate that after cerebral ischemia cGMP synthesis was increased in the CA1-asubfield, It is possible that astrocytes play an important role in the regulation of metabolism in the early stage after ischemia-reperfusion.