BACKGROUND:Restenosis easily occurs after stent implantation,thus it is worthy optimizing the stent design and evaluating its structural safety.OBJECTIVE:To simulate the deformation of balloon-expandable stainless steel stents by the finite element method,and calculated the radial displacements and stresses after expansion in different designs.DESIGN:A comparative calculated analysis.SETTING:Laboratory of Laser Processing Technology,South China Normal University.MATERIALS:The experiment was carried out in the Laboratory of Laser Processing Technology,South China Normal University in October,2006.The model of slotted-tube stent was used.METHODS:The simulations were carried out to expand a stainless steel stent with 2 mm in outer diameter,10 mm in length and 0.09 mm in strut width.Due to the symmetry of the stent by utilizing the correct boundary conditions,a half model was used to simulate the deformation process.①In stent I,the slot length was 2.0,4.0 and 4.0 mm for a,b and c respectively.In stent Ⅱ,the slot length was 1.5,4.5 and 4.0 mm for a,b and c respectively.In stent Ⅲ,the slot length was 1.8,4.2 and 4.0 mm for a,b and c respectively.Three points(A,B and C)in vary strut were selected to study the displacement during the process of deformation.The pressure applied as a surface load on the inner stent surface was 0.5 Mpa.②The dimensions and radial displacements of the three stent designs in the process of expansion were calculated,and the changes of deformation stresses were observed in the third design.MAIN OUTCOME MEASURES:① The dimensions and radial displacements of the three stent designs in the process of expansion were calculated;②The changes of deformation stresses were observed in the third design.RESULTS:The shape of the expended stent I looked like a dumbbell.The maximum radial displacement of point C obtained is found to be 2.1 mm,and the point B obtained the smallest radial displacement of 0.3 mm in the three defined points.In stent Ⅱ,the maximum radial displacement obtained is found to be point B of 2.1 mm,and the point C obtained the smallest radial displacement of 1.20 mm in lhe three defined point,which obtained a spindly shaped stents.In stent Ⅲ,the maximum radial displacement obtained is found to be point B of 2.2 mm,and the point A obtained the smallest radial displacement of 1.85 mm in the three labeled point,which produce more uniform expansion than the last two stent designs.②In stent Ⅲ,the stresses and the radial displacements achieved as the pressure increased gradually.CONCLUSION:The stress concentrations and the uniformity of the expanded stent can be decreased through optimizing the stent design by finite element method,which can be used in optimizing the stent design and evaluating the structural safety of stents.

Objective To study the ratios between several pairs of endogenous androgens in morning urine samples from male and female athletes, so as to define their reference ranges.Also to study the effects of large loading and strengthening exercises on these ratios,which may give a halp to eliminating the misjudgement caused by stimulant misuses.Methods The steroid hormones were detected by GC-MS method through the American made HP5890 and HP5971 GC-MS,with methyl testosterone as an internal standard.The hormone concentrations were calculated by means of integral analysis to each specific ionic peak.Results The ratios An-Etio,5?/5? and T/ET in male athletes were all significantly higher than those in females(P

Objective To explore the protective effect of folic acid supplementation in different ways on lipopolysaccharide-induced external malformations and skeletal malformations in mice.Methods The pregnant mice were divided into six groups randomly,including saline control group,FA control group,LPS group,LPS+FAig group,LPS+FAip group,and LPS+FAdw group.All dams were medicated on gestational day 8～12,and then sacrificed on gestational day 18,for each litter,the number of live fetuses,dead fetuses,resorption fetuses and external malformations of live fetuses were all counted.All fetuses were subsequently evaluated the skeletal malformations.Results A low dose of LPS injection during the second trimester resulted in external and skeletal malformations.Exencephaly and encephalomeningocele were two of the most common external malformations,skeletal malformations consisted mainly of the incompletion of supraoccipital ossification,sternal malformation and rib malformation.FA supplementation by three ways all attenuated the external and skeletal malformations.And the best protective effect was by oral administration.The incidence of external,sternal and rib malformation was all decreased.Conclusions Three ways can prevent the mice during the second trimester from the external and skeletal malformations caused by LPS injection,and the best protective effect was by intragastric administration.

As an important medical instrument in percutaneous transluminal coronary angioplasty, endovascular stents must have excellent biocompatibility. In this paper, after a description of the performance and fabrication process of stents, we analyzed the technology to improve the biocompatibility of stents during the fabrication process which is the effective method for decreasing the rate of restenosis.
Angioplasty, Balloon, Coronary ; Animals ; Coronary Disease ; therapy ; Coronary Restenosis ; prevention & control ; Humans ; Stents

Objective To assess the diet quality of pregnant women during the second trimester using the dietary inflammatory index ( DII) and to explore the correlation between the DII in second trimester of preg-nancy and preterm delivery.Methods A total of 253 women with singleton pregnancy in 16-20 gestational weeks who had received routine prenatal care between August 2014 and April 2015 at the First Affiliated Hospi-tal of Anhui Medical University were enrolled with cluster random sampling.The included women were asked to recall daily dietary intake in the 3 days prior to the survey.All dietary data were analyzed for energy and nutri-ents intake with a nutritional analysis software, followed by calculation of DII according to previous reports. Based on quartiles of the DII scores, the participants were divided into three groups, namely the anti-inflam-matory group (DII<-5.10), intermediate group (DII -5.10--2.55), and the pro-inflammatory group (DII>-2.55).The participants were followed up until delivery and the pregnancy outcomes were recorded. The relationship between the DII in second trimester of pregnancy and preterm delivery were analyzed. Results DII scores of the 253 pregnant women during the second trimester of pregnancy ranged from -7.913 to 3.872.The risks of preterm birth in the anti-inflammatory diet group, the intermediate group, and the pro-inflammatory diet group were 0, 1.6%, and 6.3%, respectively, with statistically significant differences among the groups (P=0.034).The higher DII scores (pro-inflammatory) were associated with higher inci-dence of preterm birth ( P<0.05 ) .Conclusion DII may be used to assess diet quality of pregnant women during the second trimester and to predict the risk of preterm birth.

Osteosarcoma needs to continuously induce angiogenesis to satisfy its own nutritional supply in the process of development. Therefore, the inhibition of osteosarcoma cell-induced angiogenesis as a target has become a research hot in recent years. Currently, vascular inhibitors targeting mRNA-encoded protein have been applied in clinic, but the efficacy is poor. Non-coding RNA (ncRNA) is a type of RNA molecules that do not participate in protein coding. ncRNA can regulate the angiogenesis of osteosarcoma by regulating the secretion of vascular factors such as vascular endothelial growth factor, angiogenin-2 and hypoxia-inducible factor 1 or the interaction between ncRNAs. This article reviews the role of ncRNA in the angiogenesis of osteosarcoma to provide references for clinical targeted therapy strategies for osteosarcoma.

BACKGROUND:Postoperative delirium is one of the serious complications after total knee arthroplasty,usually occurring 1-5 days after surgery,with confusion and cognitive impairment as the main manifestations,which is not conducive to the recovery of joint function in elderly patients.At present,the risk factors affecting delirium after total knee arthroplasty in the elderly are not clear,and there is a lack of clinical prediction studies to directly present them for promotion and application. OBJECTIVE:To explore the risk factors of delirium after total knee arthroplasty in elderly patients and establish a prediction model of nomogram. METHODS:Medical record data of 116 elderly patients receiving total knee arthroplasty treated in Ganzhou Hospital of Traditional Chinese Medicine,Jiangxi University of Chinese Medicine from January 2019 to December 2021 were retrospectively analyzed,of which 29 elderly patients with delirium after total knee arthroplasty were selected as the observation group,and the remaining 87 elderly patients without delirium after total knee arthroplasty were selected as the control group.Preoperative general clinical data,laboratory examination results,and surgical data were compared between the two groups.Multivariate Logistic regression analysis was used to analyze risk factors for delirium after total knee arthroplasty in elderly patients.The receiver operating characteristic curve was used to analyze the independent risk factors and obtain the best cut-off value.The nomogram model was constructed by R software. RESULTS AND CONCLUSION:(1)There were significant differences in age,cerebrovascular accident history,preoperative hospital stay,preoperative albumin,hemoglobin,American Society of Anesthesiologists classification,operation time,anesthesia time,and intraoperative blood transfusion volume between the two groups(P<0.05).(2)Multivariate Logistic regression analysis showed that old age,long hospital stay before surgery,high American Society of Anesthesiologists classification grade,and long operation time were risk factors for postoperative delirium in elderly knee arthroplasty patients,while high albumin and high hemoglobin were protective factors for postoperative delirium in elderly knee arthroplasty patients.(3)The areas under the curve of age,preoperative hospital stay,albumin,hemoglobin,American Society of Anesthesiologists classification grade,and operation time were 0.784,0.706,0.853,0.762,0.617,and 0.542,respectively.The optimal cut-off values were 75 years,7 days,40 g/L,125 g/L,3 and 200 minutes,respectively.(4)After internal data for verification,the consistency index was 0.974.The actual curve of the model was in good agreement with the ideal curve.(5)These results indicate that this nomogram model based on old age,long hospital stay,high American Society of Anesthesiologists classification grade,low albumin,low hemoglobin,and long operation time has far-reaching clinical significance for early identification,early warning and diagnosis of delirium risk in elderly patients after total knee arthroplasty.

Objective:To detect blood samples from clinically confirmed cases infected with the 2019 novel coronavirus (2019-nCoV) by fluorescence immunochromatography, colloidal gold immunoassay and micro neutralization test and compare differences in result and provide useful approaches to clinical and epidemiological investigation.Methods:The 2019-nCoV IgG/IgM antibody kit (Fluorescent immuno-chromatography) and the 2019-nCoV antibody test kit (Colloidal gold immunoassay) from Guangzhou Wanfu biotechnology Limited by Share Ltd, and the micro neutralization test established by a 2019-nCoV strain isolated by the laboratory in Guangdong Provincial Center for Diseases Control and Prevention were used to detect serum samples of clinically confirmed patients, in the Guangdong Province Second People′s Hospital, China.Results:A total of 113 serum samples from clinically confirmed cases infected with the 2019-nCoV were collected in Guangdong 2 nd People′s Hospital. The median age of the patients was 47.50 (32.00, 57.00) years and the gender ratio was 2.77∶1; The highest neutralizing antibody titer of micro neutralization test was 1∶1 024; Taking the result of micro neutralization test as gold standard, the sensitivity for colloidal gold immunoassay was greater than that of fluorescence immunochromatography (94.74% vs 82.46%), and the Kappa value for colloidal gold immunoassay and fluorescence immunochromatography was 85.84% and 75.24% respectively; at the same time, the negative predictive value and the positive predictive value for them were 94.44%, 91.53% and 83.87%, 92.16% respectively. Conclusions:In the serological method for the detection of the 2019-nCoV infection, the sensitivity and Kappa value for colloidal gold immunoassay were higher than those of fluorescent immunochromatography when the result of micro neutralization test was taken as the gold standard, which was more suitable for rapid detection of cases with the 2019-nCoV infection.

BACKGROUND:It has been demonstrated that osteoclast activation plays an important role in skeletal system-related diseases.The mechanism of regulation of osteoclast activation by extracellular vesicles carrying non-coding RNA has not been fully elucidated. OBJECTIVE:To review and summarize relevant literature in and outside China,and to review the regulation of osteoclast activation by different non-coding RNAs in extracellular vesicles in different diseases,so as to provide a certain direction for subsequent research. METHODS:"Non-coding RNA,miRNA,lncRNA,circRNA,snoRNA,osteoclasts,extracellular vesicles,exosome,microparticle,apoptotic bodies"were used as search terms to search the databases of CNKI,WanFang,and VIP."Extracellular vesicles,exosome,microparticle,apoptotic bodies,non-coding RNA,miRNA,lncRNA,circRNA,snoRNA,osteoclast"were used as search terms to search PubMed.Finally,71 articles were included. RESULTS AND CONCLUSION:(1)The activation of osteoclasts is affected by many factors,among which the specific mechanism of non-coding RNA regulating osteoclast activation is not clear.(2)Extracellular vesicles can be secreted by osteoblasts,bone marrow mesenchymal stem cells,tumor cells and other cells.As a carrier of intercellular communication,extracellular vesicles can carry non-coding RNA to regulate osteoclast activation.(3)In the current studies on the regulation of osteoclast activation by extracellular vesicles carrying non-coding RNA,most of the diseases are osteoporosis,followed by tumor bone metastasis,and most types of non-coding RNA are miRNA.(4)There are relatively few studies on the regulation of extracellular vesicles carrying lncRNA and circRNA and snoRNA on osteoclast activation,and the regulatory mechanism is mainly ceRNA mechanism.(5)In conclusion,an in-depth study of the regulatory mechanism of extracellular vesicles carrying non-coding RNA on osteoclast activation is helpful to find key targets for the treatment of skeletal system-related diseases.

Objective:To discuss the therapeutic effect of resveratrol on the temporomandibular joint osteoarthritis(TMJOA),and to clarify the related mechanism.Methods:Forty-five SD rats were randomly divided into control group,model group,and resveratrol group,and there were 15 rats in each group.The rats in model group and resveratrol group were intra-articularly injected with 50 μL of 20 g·L-1 monosodium iodoacetate(MIA)to set TMJOA rat models,while the rats in control group were injected with an equal volume of normal saline.Three weeks after modeling,the rats in resveratrol group received an injection of 80 μL resveratrol solution,once a week for three weeks,while the rats in control and model groups were injected with an equal volume of normal saline.Micro-computed tomography(Micro-CT)system was used to detect the condyle structure and the bone volume fraction(BV/TV),trabecular thickness(Tb.Th),trabecular spacing(Tb.Sp),and trabecular number(Tb.N)of the rats in various groups were calculated;HE staining and toluidine blue staining were used to observe the pathomorphology of temporomandibular joint(TMJ)tissue of the rats in various groups;immunohistochemistry was used to detect the expression levels of SRY-related HMG box(SOX)-9,matrix metalloproteinase(MMP)-13,silent information regulator(Sirt)1,phosphatidylinositol 3-kinase(PI3K),phosphorylated protein kinase B(p-Akt),and phosphorylated mammalian target of rapamycin(p-mTOR)in TMJ tissue of the rats in various groups;real-time quantitative PCR(RT-qPCR)method was used to detect the expression levels of SOX-9,MMP-13,Sirt1,PI3K,mTOR,and Akt mRNA in TMJ tissue of the rats in various groups.Results:Three weeks after modeling,condylar bone was destructed,the surface was roughness,and continuity interruption were observed,indicating TMJOA model of the rats was established successfully.The Micro-CT system results showed that the condylar surface of the rats in control group was smooth and regularly shaped,with continuous bone texture;the rats in model group had significant condylar destruction,disrupted continuity,surface roughness,and varying degrees of bone defects;the rats in resveratrol group showed alleviated condylar lesions and improved appearance.Compared with control group,the BV/TV and Tb.Th of the rats in model group were significantly decreased(P<0.05),and Tb.Sp was significantly increased(P<0.05);compared with model group,the BV/TV and Tb.Th of the rats in resveratrol group were significantly increased(P<0.05),and the Tb.Sp was significantly decreased(P<0.05).The HE staining results showed clear layers and orderly chondrocyte arrangement in condyle of the rats in control group;the rats in model group showed rough uneven surface,obvious defects,and typical TMJOA features;the rats in resveratrol group showed slightly rough surface with generally clear layers and orderly arranged cells.The toluidine blue staining results showed distinct blue-purple staining of chondrocytes in hypertrophic layer of the rats in control group;pale staining or even loss of staining in some areas of the rats in model group;and distinct and relatively uniform staining in hypertrophic layer of the rats in resveratrol group.The immunohistochemistry results showed that compared with control group,the expression levels of MMP-13,PI3K,p-Akt,and p-mTOR proteins in TMJ tissue of the rats in model group were significantly increased(P<0.05),while the expression levels of SOX-9 and Sirt1 proteins in TMJ tissue of the rats were significantly decreased(P<0.05);compared with model group,the expression levels of SOX-9 and Sirt1 proteins in TMJ tissue of the rats in resveratrol group were significantly increased(P<0.05),whereas the expression levels of MMP-13,PI3K,p-Akt,and p-mTOR proteins were significantly decreased(P<0.05).The RT-qPCR results showed that compared with control group,the expression levels of MMP-13,PI3K,Akt,and mTOR mRNA in TMJ tissue of the rats in model group were significantly increased(P<0.05),while the expression levels of SOX-9 and Sirt1 mRNA were significantly decreased(P<0.05);compared with model group,the expression levels of SOX-9 and Sirt1 mRNA in TMJ tissue of the rats in resveratrol group were significantly increased(P<0.05),whereas the expression levels of MMP-13,PI3K,Akt,and mTOR mRNA were significantly decreased(P<0.05).Conclusion:Resveratrol has therapeutic effect on TMJOA,and its mechanism may be related to the activation of Sirt1 and inhibition of the PI3K-Akt-mTOR signaling pathway.