BACKGROUND:Biliary stent restenosis is one of the main long-term complications following biliary stent restenosis implantation,which affects its application.OBJECTIVE:To evaluate the reasons for the biliary stent restenosis and to explore corresponding prevention methods.METHODS:A computer-based online search of MEDLINE,Cochrane library,CNKI and VIP between January 1989 and August 2009 was performed to search related articles with the key words of "biliary metal stent,reobstruction,and interventional therapy".Literatures related to biliary stent restenosis were selected,in the same field,the articles published lately or published by authoritative journals were preferred.A total of 171 articles were searched and 22 documents were included according to inclusion and exclusion criteria.RESULTS AND CONCLUSION:Tumor growth,gallstone formation and inflammatory hyperplasia are the main reasons for restenosis following biliary metal stent implantation.The interventional therapy is an effective way for the patients of stent restenosis.Simultaneously,the therapeutic efficacy and living quality of patients can be improved by noticing preoperative conditions,in-time detecting and controlling biliary infection,reducing complications as well as strengthening postoperative combined therapy.

BACKGROUND:It generally thought that based on cholangiography,biliary tract stents implantation can achieve a same long-term therapeutic efficacy as resection,and obtain good clinical outcomes in treating hilar cholangiocarcinoma when combined with percutaneous portcatheter system.OBJECTIVE:To evaluate the clinical methods of double interventional therapy and the biocompatibility between stent and host in hilar cholangiocarcinoma following stant implantation.METHODS:The databases of MEDLINE,Cochrane library,CNKI and VIP were retrieved with deadline of August 2009.Medium survival time and jaundice decrease rate,complication rate as well as biocompatibility between stent and host were sewed as assessment index.Clinical studies addressing double interventional therapy for treating proximal bile duct cancer were included,and animal studies were excluded.A total of 156 literatures were obtained initially by computer,and 25 literatures were included in further analysis.RESULTS AND CONCLUSION:In vitro test showed that stents carrying antibiotic,silver,or Escherichia coil,which may prevent adhesion of bacteria,however,it obtained poor clinical results.Chitosan is a natural cationic polymer and possess good biocompatibility,antibiosis and biodegradability.For the compare of the therapeutic effectiveness among different surgical procedure,it found that the decrease of total bilirubin were more faster in the internal and external drainage group than the resection group,however,the difference had no statistically significance.According to the Kaplan-Meier survival analysis,the medium survival time of 7 patients in the resection group was 16 months.The 1,3,5 years survival rate were 57.1%(4/7),28.6%(2/7),14.3%(1/7),respectively.Among the double interventional therapy group,the medium survival time of 19 patients was 18 months,and the 1,3,5 years survival rate were 52.6%(10/19),27.8%(5/19),15.8%(3/19),respectively.The medium survival time was 12 months in 14 patients of the control group,with 1,3,5 years survival rate of 57.1%,28.6%,14.2%,respectively.The results demonstrated that biliary tract stents implantation combined with percutaneous portcatheter system can improve life quality and prolong survival time of patients with hilar cholangiocarcinoma.

Objective To evaluate the stability of U6 and let-7a as internal reference genes of miRNAs in RTqPCR by using femoral head samples of cartilage tissue from inbred DA rats.Methods Total RNA was extracted from femoral head cartilage tissues of female DA rats at three different time points,i.e.at birth (D0),ablactation (D21) and maturation (D42).The expressions of different miRNAs (miR-1,-25,-26a,-140,-146a,-150,-181a,-195,-223 and-337) were detected by RT-qPCR using U6 or let-7a as the internal reference.The two sets of miR expression were compared with the results from Solexa sequencing in our pioneer work to evaluate the stability of the two internal references.Results The relative values of U6 (P =0.045) and let-7a (P =0.021 5) revealed significant difference in the D42 sample.Both in U6 and let-7a systems,miR-26a,-140,-223,and-337 showed a similar tendency in expression and quantification but miR-1 and-146a did not have significant differences.miR-25,-150,-181a and-195 differed significantly (P＜0.05).Comparison of absolute quantification results between the two generations' sequencing showed that let-7a is more stable than U6.Conclusion Let-7a is more suitable to be used as the internal reference gene in RT-qPCR for miRNAs in cartilage tissue.

Objective:To evaluate and screen the anti-atrial ifbrillation drug with multiion channel targets by micro-electrode chip technology in a rapid atrial pacing (RAP) rabbit model.
Methods:A total of 32 rabbits were randomly divided into 4 groups, n=8 in each group. Potassium channel blocker (TEA) group, Potassium channel blocker (BaCl2) group, Potassium channel blocker (CdCl2) group and Amiodarone group.
The electrode was inserted into right atrium via internal jugular vein with rapid right atrial pacing (600 beat/min) and the effect of each anti-atrial ifbrillation drug on ifeld action potential (fAPD) were measured in different groups.
Results:With 24 hour RAP, the fAPD was prolonged from (176.67 ± 8.66) ms to (196.11 ± 10.76) ms, P=0.012 in TEA group;from (182.22 ± 12.87) ms to (191.11 ± 13.09) ms, P=0.039 in BaCl2 group;from (178.33±7.85) ms to (206.67 ± 9.70) ms, P=0.0015 in CdCl2 group;from (167.38 ± 13.67) ms to (185 ± 15.14) ms, P=0.002 in Amiodarone group.
Conclusion: RAP induced atrial fibrillation in experimental rabbit model is a simple and feasible method for screening the anti-atrial fibrillation drugs, combining with micro-electrode chip technology, it might be used for developing the new product.

Objective:This study introduces a novel approach utilizing a self-made drug delivery cannula implanted into the cerebellomedullary cistern(CMC)of rats to allow repeated administrations in conscious subjects.Methods:A self-made medication cannula is inserted through a drilled hole at the midpoint of the occipital crest of the rat's skull,de-scending along the inner wall of the occipital bone until reaching the CMC,and securing it in place with skull screws and self-curing resin.Lipopolysaccharide(LPS)is injected into the CMC to induce neuroinflammation,and the feasibility of this method is assessed using X-ray imaging,behavioral testing,and immunofluorescence staining.Results:The place-ment of the brain cannula was confirmed using X-ray film and pontamine sky blue staining.Rats in the LPS group exhib-ited a lower facial mechanical pain threshold compared to the Control group(P＜0.001),along with reduced residence time in the open field center(P＜0.01).Immunofluorescence staining revealed LPS-induced activation of caudal spinal trigeminal nucleus(SpVc)microglia.Conclusion:This method proves to be suitable for multiple administrations to the cerebellomedullary cistern of conscious rats,enabling the study of the SpVc's role in pain modulation.

Objective:To explore the occurrence time and risk factors of deep vein thrombosis (DVT) in patients with acute cerebral infarction, so as to guide clinical prevention and treatment.Methods:1 129 patients with acute cerebral infarction treated in Beijing Tiantan Hospital from May 2014 to May 2016 were selected as the research objects. According to whether DVT occurred, the patients were divided into DVT group ( n=22) and non DVT group ( n=1 107); The information was analyzed retrospectively and the occurrence time of DVT was counted. The independent risk factors of acute cerebral infarction complicated with DVT were analyzed by univariate and multivariate logistic regression. Results:The time of DVT in patients with acute cerebral infarction was 10.5 (4-14) days. Univariate analysis showed that there were significant differences in age, gender, atrial fibrillation, smoking, drinking, chronic obstructive pulmonary disease, peripheral artery disease, renal failure, anticoagulants, BMI, white blood cell, blood glucose at admission and length of stay between the DVT group and the non DVT group ( P<0.05). Multiple factors further confirmed that renal failure [odds ratio ( OR)=57.421; 95% confidence interval ( CI), 5.792-569.314)] and length of hospital stay ( OR=1.148; 95% CI: 1.071-1.232) were independent risk factors for DVT. Conclusions:The median time of DVT in patients with acute cerebral infarction was 10.5 days. Renal failure and hospital stay were independent influencing factors of DVT in patients with acute cerebral infarction. This is helpful to determine the best prevention and treatment duration of DVT in patients with acute cerebral infarction, make rational use of medical resources and formulate personalized prevention and treatment strategies.

Two strains of porcine reproductive and respiratory syndrome virus (PRRSV) were isolated in 2006 and 2016 and designated as FZ06A and FZ16A, respectively. Inoculation experiments showed that FZ06A caused 100% morbidity and 60% mortality, while FZ16A caused 100% morbidity without death. By using genomic sequence and phylogenetic analyses, close relationships between a Chinese highly pathogenic PRRSV strain and the FZ06A and FZ16A strains were observed. Based on the achieved results, multiple genomic variations in Nsp2, a unique N-glycosylation site (N³³→K³³), and a K151 amino acid (AA) substitution for virulence in the GP5 of FZ16A were detected; except the 30 AA deletion in the Nsp2-coding region. Inoculation experiments were conducted and weaker virulence of FZ16A than FZ06A was observed. Based on our results, a 30 AA deletion in the Nsp2-coding region is an unreliable genomic indicator of a high virulence PRRSV strain. The Nsp2 and GP5 differences, in addition to the virulence difference between these two highly pathogenic PRRSV strains, have the potential to be used to establish a basis for further study of PRRSV virulence determinants and to provide data useful in the development of vaccines against this economically devastating disease.
Asian Continental Ancestry Group ; China ; Genomics ; Humans ; Mortality ; Phylogeny ; Porcine Reproductive and Respiratory Syndrome ; Porcine respiratory and reproductive syndrome virus ; Vaccines ; Virulence

Objective:To explore the feasibility and accuracy of three-dimensional (3D) modeling methods based on ultrasound imaging data for normal and abnormal fetal cardiac structures, and to construct a methodology system for 3D printing of fetal heart based on ultrasound.Methods:A total of 93 fetuses examined in Tangdu Hospital of Air Force Military Medical University from January to December 2019 were selected. Fetal echocardiography was obtained using spatio-temporal image correlation (STIC). Ninety-three hearts were 3D modeled by blood flow modeling, blood pool modeling and cavity modeling, and printed by stereolithography technique. The data measured on the 3D digital models and 3D printed solid models were compared with the corresponding fetal echocardiographic images respectively in order to evaluate the accuracy of the modeling methods.Results:The fetal cardiac blood flow models based on Doppler flow image data showed the malformation and trend of small blood vessels. The fetal cardiac structure models printed based on blood pool modeling displayed the malformation of heart and large blood vessels. Models printed based on cavity modeling method accurately displayed valve and structural defects.For 83 normal fetal hearts, the long diameters of left and right ventricles measured on echocardiography [(15.3±1.9)mm, (13.2±1.9)mm] were compared with those measured on digital models [(15.1±1.9)mm, (12.9±1.9)mm] and 3D printed models[(15.1±1.9)mm, (13.0±1.9)mm], respectively, and there were no significant differences between any two groups of them ( P>0.05). Bland-Altman showed good consistency for all measurements within and between operators. Conclusions:The three modeling methods, including blood flow modeling, blood pool modeling and cavity modeling, have their own advantages in displaying different types of fetal heart malformations. Appropriate modeling methods should be selected for 3D modeling and printing to make up for the limitations of single modeling method. The consistency between measurements on 3D models and those on echocardiography is high, and the repeatability between operators is good.

Anaplastic thyroid carcinoma(ATC)is the most aggressive malignancy with poor prognosis.The pathogenesis of ATC is complex,and there is no effective treatment at present.In recent years,with the deep understanding of the genetic(such as BRAF V600E,TP53,TERT,PIK3CA mutations,etc.)and epigenetic(such as histone methylation,histone deacetylation,microRNA regulatory pathways,etc.)changes driving ATC,molecular targeted therapy has brought new hope to ATC patients.This article reviews the molecular mechanisms of ATC and the latest achievements in targeted therapy and other therapies.

Objective:To investigate the expression of HBB in anaplastic thyroid cancer(ATC)cells and its regulatory effect on proliferation,invasion,migration and apoptosis of ATC cells and its potential mechanism.Methods:The expression of HBB in thyroid cancer and paracancerous tissues was analyzed through TIMER database.The correlation between the expression of HBB and the overall survival time of thyroid cancer patients was analyzed through KM-plotter database.The expression of HBB mRNA in ATC cells was detected by RT-qPCR.The HBB knockout or overexpression plasmid was transfected into ATC cells.The expression of HBB protein was detected by Western blot.The proliferation activity was detected by CCK-8 assay.The migration and invasion ability was detected by Transwell assay.The apoptosis was detected by flow cytometry.The expression of β-catenin was detected by Western blot.Results:The expression of HBB was low in thyroid cancer,and the overall survival time of patients with high expression of HBB was high.The expression of HBB protein was down-regulated in ATC cells.Knockout of HBB increased the ability of proliferation,migration and invasion of ATC cells and the expression of β-catenin protein,and inhibited apoptosis.However,overexpression of HBB decreased the ability of proliferation,migration and invasion of ATC cells and the expression of β-catenin protein,and promoted apoptosis.Conclusions:High HBB expression is associated with higher overall survival in patients with thyroid cancer.It may inhibit the proliferation,migration and invasion of ATC cells and promote apoptosis through Wnt/β-catenin signal pathway.