1.Mechanical effect of calcium polyphosphate fiber on reinforcing calcium phosphate bone cement composites
Lixin XU ; Xueting SHI ; Yanping WANG ; Zongli SHI
Chinese Journal of Tissue Engineering Research 2009;13(38):7474-7476
AIM: To prepare α-tricalcium phosphate (α-TCP)/calcium polyphosphate (CPP) fiber and to study the feasibility of CPP fiber to reinforce calcium phosphate bone cement composites. METHODS: Firstly,α-TCP powder was synthesized using chemical sediment method. Secondly, the α-TCP was mixed with CPP fiber according to different contents and lengths. Finally, bone cement was tempered with firming agent. Solidification time and mechanical property of the samples were measured. Microstructure of hardened sample was observed with scanning electron microscope. RESULTS: When the amount of CPP fibers was 10% and the length was 2 mm, the compressive strength reached 62.5 MPa and the rupture strength reached 12.4 MPa. Scanning electron microscope suggested that CPP fibers with great associativity were well distributed in bone cement. After immersing in Ringer fluid for two months, the CPP fibers did not biodegrade obviously and still had certain function to increase strength and toughness. CONCLUSION: To a certain extent, the CPP fiber can increase strength and toughness of bone cement. Furthermore, α-TCP/CPP composites have good mechanical properties and biocompatibility.
2.Performance of calcium phosphate bone cement using chitosan and gelatin as well as citric acid as hardening liquid
Lixin XU ; Xueting SHI ; Yanping WANG ; Zongli SHI
Chinese Journal of Tissue Engineering Research 2008;12(32):6381-6384
BACKGROUND:When bone cement solidifies fast,the bone cement consistency will be decreased.resulting in difficulty in molding.DESIGN,TIME AND SETTING:Open experiment,performed in the Laboratory of Department of Materials,Lanzhou Jiaotong University between March 2005 and August 2006.gelatin were mixed with citric acid to produce hardening liquid.Then bone cement power and hardening liquid were mixed to form a paste,I.e.,bone cement.METHODS:Setting time of bone cement was determined using a Vicat apparatus.The compressive strength of bone cement at different proportions was tested using MTS-810 material tester.After 2 months of physiological saline soaking at 37℃.the microstructure of solidified bone cement was observed using scanning electron microscope.MAIN OUTCOME MEASURES:Setting time and compressive strength of bone cement,pH value of hydrated bone cement and the microstructure.RESULTS:After adding chitosan and gelatin in the hardening liquid.the consistency of the concoction obviously increased,the setting time became a little longer and the water-resistance of samples was enhanced.therefore the samples could be easily molded.But the compressive strength of the bone cement decreased a little.The pH value of the hydrated bone cement increased gradually with time and was close to the pH value of physiological saline at hour 24.The compressive strength of bone cement was achieyed at 24 hours and it almost did not change after 48 hours.the drawback of ceramic HA,including sintering and difficulties in shaping.It has the characteristics of simple-producing,easy application and low heat energy.
3.Effect of enteral nutrition treatment on metabolism and serum adiponectin level in elderly patients with metabolic syndrome
Linping SHI ; Wei WANG ; Lei SHI ; Le XU
Chinese Journal of Geriatrics 2017;36(2):190-194
Objective To observe the effect of enteral nutrition therapy on metabolic status and adiponectin levels in elderly patients with metabolic syndrome (MS) complicated with nonalcoholic fatty liver disease (NAFLD).Methods 92 elderly hospitalized patients with mild to moderate non-alcoholic fatty liver disease underwent enteral nutrition (EN,n=46) and total parenteral nutrition (TPN,n=46) for 2 months.Body mass index,triceps skin-fold thickness,waist hip ratio,serum high-molecular weight (HMW) form of adiponectin,fasting blood glucose,postprandial 2-hour blood glucose,glycosylated hemoglobin,plasma insulin,alanine aminotransferase,aspartate aminotransferase,γ-glutamyltransferase,total bilirubin,direct bilirubin,total cholesterol,triglyceride,low density lipoprotein cholesterol,high density lipoprotein cholesterol,the blood pressure and liver ultrasound test were detected.The insulin resistance (HOMA-IR) was used to assess insulin resistance.Results In pre-versus post-treatment,serum level of HMW adiponectin [(6.8 ± 4.0) μg/L vs.(7.1 ± 3.9) μg/L,P > 0.05 in enteral nutrition],and [(6.8 ± 3.5) μg/L vs.(5.0 ± 1.1)μg/L(P<0.05)] in parenteral nutrition were found.The significantly decreased body mass index in the obese patients (P<0.05),significantly improved values of 2-hour blood glucose,glycated hemoglobin,liver function,triglycerides,low-density lipoprotein cholesterol levels (all P<0.05),and no obvious change in HOMA-IR were found after two months of enteral nutrition treatment.There were no significant changes in indicators mentioned above in TPN group after 2 months of treatment.Conclusions Enteral nutrition therapy can improve the glucose metabolism,lipid metabolism,the non-alcoholic fatty liver disease and body mass index,affect the level of adiponectin in the elderly patients with MS and NAFLD.It is vital to body metabolism.
4.The Design Method of Introduction in Medical Organic Chemistry Course
Xu WANG ; Jingfen LI ; Weiguo SHI
Chinese Journal of Medical Education Research 2003;0(02):-
In medical organic chemistry education, seven design method of introduction are put forward by using teaching art in educational segment, allowing students to enhance the study activity in lively atmosphere.
5.Clinical observation on a correlation between Helicobacter pylori infection and reflux esophagitis in the elderly
Chinese Journal of Geriatrics 2017;36(7):773-776
Objectives To study a correlation between Helicobacter pylori Infection and reflux esophagitis in the elderly.Methods In a prospective study,180 cases of elderly patients with confirmed diagnosis of reflux esophagitis were consecutively recruited in our hospital from 2010-2016 years.180 reflux esophagitis patients were divided into three groups:non-HP infection group(group A,n=78),and 102 HP infection patients were subdivided into B1 group(n=51)with single-drug therapy and B2 group(n=51)with multiple drugs therapy.The groups A and B1 were treated with only esomeprazole 20 mg/bid for 8 weeks.The group B2 was treated with esomeprazole 20 mg/bid for 8 weeks,colloidal bismuth 200 mg/bid for 2 weeks plus two kinds of antibiotics(taking any 2 of the following 3:Amoxicillin 1 000 mg/bid,Clarithromycin 500 mg/bid and tinidazole 500 mg/bid)for 2 weeks.Gastroscope and cognate biopsy,helicobacter pylori detection,and 24 h esophagus pH monitoring was performed before and after the therapy.Results Group A,B1 and B2 showed that the total effective rate of symptoms improvement were more than 95.0% in post-versus pre-treatment(P<0.05),the gastro scope evidence-based total effective rate of reflux esophagitis were 84.6%、80.4%、82.4%(66/78,41/51,42/51)after therapy(P<0.05),and 24 h esophagus pH was significantly improved(P<0.05)after therapy.But the differences in above indexes showed no statistical significance between three groups(P>0.05).After HP eradication therapy,HP negative rate was 90.2%(46/51)in multiple drugs group.Conclusions Reflux esophagitis in elderly patients with Helicobacter pylori infection can be treated with anti-HP drugs,but the treatment should include drugs inhibiting gastric acid,so as to effectively prevent the progress of reflux esophagitis.There is no clear correlation between irritation of esophagus by reflux contents and Helicobacter pylori infection.
6.QUANTITATIVE STUDY ON THE CAPILLARIES OF THE HUMAN THALAMUS AND ITS ADJACENT STRUCTURES
Tiejun XU ; Pingyu WANG ; Zhongliang SHI
Acta Anatomica Sinica 1953;0(01):-
The brains from four newborns were used in this study. After continuous artery-vein injection with coloured materials, the brains were embedded in nitrocellulose. and coronal sections of 500?m, 100?m and 30?m in thickness were prepared in alternative and successive sequence. The 500?m sections were cleared in wintergreen oil and mounted, and the 100?m and 30?m sections were stained with thionin. The diameter and density of capillaries in thalamus and its adjacent structures were measured by means of Leitz MPV-Tasplus multifunction image analyser. All the data were dealt with variance and correlation analysis statistically. The capillary density of the thalamus and its adjacent structures varied obviously. The value in putamen, cellular layers of lateral geniculate body, anterior thalamic nucleus and subthalamic nucleus was the highest; while the value in dorsomedial nucleus, ventral lateral nucleus, pulvinar nucleus, ventral posterior lateral nucleus, lateral posterior nucleus, centromedian nucleus, medial geniculate body, ventral anterior nucleus and internal medullary lamina was the intermediate; however, the value in internal capsule and fibrous layers of lateral geniculate body was the lowest. The capillary diameter of ventral anterior nucleus and internal capsule was the widest; that of putamen and cellular layers of lateral geniculate body was the smallest; the rest was the intermediate. In the same measured structures, negtive correlation was shown between the capillary diameter and density.
7.THE DISTRIBUTION OF INTRATHALAMIC VESSELS IN HUMAN BRAIN
Tiejun XU ; Pingyu WANG ; Zhongliang SHI
Acta Anatomica Sinica 1955;0(03):-
The course, distribution of the intrathalamic vessels on 8 sides of newborn brains were studied by means of the continuous artery-vein infusion, Spalteholz's clearing and Nissl's staining. The brains were all cut into the coronal sections of 500 ?m, 100?m and 30?m thickness in alternate and successive order. The main arteries supplying thalamic nuclei were: 1. The thalamoperforating artery; 2. The geniculothalamic artery; 3. The medial posterior choroidal artery; 4. The medial inferior pulvinar artery; 5. The lateral ventricular choroidal artery. The thalamic veins opened respectively into the internal cerebral vein, the veins of the lateral ventricle, the veins of the interpeduncular fossa and the basal vein. There were three patterns of course relation between thalamic arteries and veins. They were solitariness, accompanying and one vein surrounded by several arteries.
8.Comparison of different catheter ablation strategies for patients with chronic atrial fibrillation
Haifeng SHI ; Xu LIU ; Xinhua WANG
Chinese Journal of Interventional Cardiology 1993;0(03):-
Objective To compare the clinical outcomes of 2 different catheter ablation strategies for patients with chronic atrial fibrillation(CAF).Methods One hundred and thirty four consecutive patients(77 males,mean age 56.8?12.3 yrs)were randomized into 2 groups of different catheter ablation strategies.All the patients suffered from frequent attacks(more than 3 times per month),drug refractory and symptomatic CAF.One group received circumferential pulmonary rein ablation(CPVA group,n=68)and the other group received complex fractionated electrogram ablation additional to CPVA(CPVA+CFEA group,n=66).All ablation was guided by 3 dimensional mapping system(CARTO).Follow-up ECG,Holter and clinical outcomes of the 2 groups within 6 months after the procedures were analyzed.Results The baseline characteristics were comparable between the 2 groups.The mean procedure time in the CPVA+CFEA group was longer than that in the CPVA group but the mean fluoroscopy time between two groups had no significant difference.After the first procedure,60%of patients in the CPVA group and 77% of patients in the CPVA +CFEA group were free from symptomatic atrial tachycardia without any use of antiarrhythmic drugs for at least 3 months(P
9.Transcatheter Ablation for Atrial Fibrillation Therapy Guided by 3-D Mapping Systems:Experience of 800 cases from single center
Xu LIU ; Xinhua WANG ; Haifeng SHI
Chinese Journal of Interventional Cardiology 1993;0(03):-
Objective To evaluate the safety and effectiveness of catheter ablation for atrial fibrillation(AF)therapy guided by 3-D mapping systems.Methods Eight hundred cases(482 male,mean age 62.1?15.6 years)were enrolled.AF was paroxysmal in 611 cases,and persistent in 189 cases.The mean left atrium diameter was 38.4 9.2 mm.Ablation was guided by EnSite-NavX in 260 cases and by CARTO in 540 cases.Circumferential pulmonary vein isolation(CPVI)was performed for paroxysmal AF,and CPVI combined with complex fractionated atrial electrograms(CFAEs)and mitral isthmus ablation was applied for persistent AF.Every case received oral anticoagulation with warfarin and class IC and class III antiarrhythmic drugs for 1 to 3 months.ECG and Holter were applied every month during follow-up.Results Seven hundred and ninty-five cases underwent the procedure successfully,with the mean procedural time 161 33 min and fluoroscopic time 17 13 min.PV isolation was achieved in 96.5% of cases for left-sided PVs,and in 98.6% of cases for right-sided PVs.Radiofrequency application terminated paroxysmal AF in 90 out of 98 cases.AF recurred in 137 cases within 2 weeks post-ablation,and subsided in 103 cases during subsequent follow-up.Fifty-seven cases underwent re-ablation and 6 cases required third ablation.Persistent AF was terminated in 30 cases(16.1%)and was converted to atrial tachycardia in 15 cases(8.1%)by CPVI.For patients receiving CFAEs ablation,persistent AF was terminated in 20 cases(10.8%)and was converted to atrial tachycardia in 23 cases(12.4%).AF recurred in 78 cases(41.9%)early after ablation and 65 cases underwent re-ablation(10 cases received third ablation).Atrial tachycardia/flutter developed in 104 cases(13.1%)after ablation,and remitted in 68 cases.Atrial tachycardia/flutter was mapped and ablated in 30 cases,and was eliminated in 23 cases.Complications:Cardiac tamponade developed in 5 cases,requiring pericardiocentesis in 3 cases and surgical repair in 2 cases.PV stenosis was present in 6(0.7%)cases,TIA in 1 case,cerebral embolism in 2 cases,mesentery artery embolism in 1 case,hemothorax in 1 case and pneumothorax in 1 case.There were femoral artery pseudo-aneurysm in 3 cases and femoral artery-vein fistula in 1 case.All the patients were cured by conservative therapy.During a mean follow-up of 16.2?5.7 months,550 cases(9.4% of them received re-ablation and 11.5% received antiarrhythmic drugs)with paroxysmal AF and 159 cases(34.9% of them received re-ablation and 28.5% received antiarrhythmic drugs)with persistent AF were free of atrial tachyarrhythmias recurrence.Conclusion Catheter ablation guided by 3-D mapping systems were safe and effective for AF therapy.CPVI alone was enough for paroxysmal AF treatment,while CPVI combined with CFAEs and isthmus ablation were preferable for persistent AF treatment,and re-ablation were needed in 40% of the patients to improve effectiveness.
10.Clinical analysis of failure factors in root canal therapy
Qiong XU ; Adan WANG ; Ying SHI
Journal of Practical Stomatology 2001;0(03):-
Objective:To analyze the failure factors in root canal therapy(RCT)by analysis of the failed cases.Methods:215 teeth of 206 patients were analyzed according to former treatment records,clinical examination,pretreatment radiographs,and root canal exploration during endodontic retreatment.Results:67.9% of failed teeth showed apical radiolucency,12.6% showed under-filled canal material without apical radiolucent area,and 8.4% involved coronal leakage.When examined with X ray,84.2% of teeth indicated under-filling,and most canals of premolars and molars had poor taper.Most missed root canals were found in maxillary first molars and premolars.18.1% of teeth had complications such as ledge and apical transportation.Conclusions:The factors associated with RCT failure involve cleaning,obturation and poor seal of root canal system resulted from inadequate shaping.Coronal leakage and missed canals also contribute to the endodontic treatment failure.