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.Relationship between recurrence of Barrett esophagus and Helicobacter pylori eradication therapy in the elderly
Chinese Journal of Geriatrics 2010;29(6):495-498
Objective To investigate the relationship between the recurrence of Barrett esophagus (BE) and Helicobacter pylori (Hp) eradication therapy, according to endoscopic follow-up outcomes in the elderly patients with BE after endoscopic argon plasma coagulation (APC). Methods A total of 201 elderly patients were enrolled to be treated with APC, including 53 patients without Hp infection (control group) and 148 cases with Hp infection (infection group), then the infection group was randomly divided into two groups: infection group A (n=74) and infection group B (n=74). After APC, all patients were given acid suppression therapy with omeprazole infusion 40 mg twice daily for 7 days, then omeprazole capsules 20 mg twice a day orally, the overall time was 2months. The patients in infection group B received Hp eradication therapy with two of the following three kinds of antibiotics for 2 weeks: amoxicillin 500 mg twice a day, clarithromycin 500 mg twice a day and tinidazole 500 mg twice a day. All patients received reexamination of endoscopy and pathology, and underwent 24-hour esophageal pH test 1, 3, 6, 12 and 24 months after treatment.Results By APC treatment for an average of 2.4 times (1-3 times), 1 month after treatment, all BE epithelium disappeared and stratified squamous epithelium was repaired completely. Reflux esophagitis (RE) and BE in some cases were found in 3 groups 3 months after therapy. The relapse incidence of RE was significantly increased at 6 months after therapy [control group: 22.6%, infection group A:12.2o%and infection group B: 17. 6%, t = 2.21, 2.17 and 2.30,P<0. 05]. At 12 months after therapy, the relapse incidence of BE was significantly increased [control group: 22.6%, infection group A: 18.9% and infection group B: 23.0%, t=2.11, 2.19 and 2.32, P<0. 05]. All patients presented pathological gastro-esophageal reflux (DeMeester index>14.72) before treatment. At 1 month after therapy, all patients returned to normal DeMeester index[control group: 14.5, infection group A: 15.2 and infection group B: 12.0, t=2.09, 2.22 and 2.15, P<0. 05]. At 6 months after treatment, DeMeester index increased (t=2.29, 2.33 and 2.14, P<0.05). But there were no significant differences among 3 groups (P>0. 05). Conclusions The elderly BE patients with HP infection in gastric antrum can receive APC treatment plus Hp eradication treatment, but it has no significant effect on long-term prognosis for BE patients. APC treatment can completely remove BE epithelium, long-term acid suppression therapy may delay recurrence of BE.
5.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
6.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.
7.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.
8.Initial circumferential pulmonary vein isolation for atrial fibrillation and re-ablation for recurrence: analysis of key target sites
Xinhua WANG ; Xu LIU ; Haifeng SHI
Chinese Journal of Interventional Cardiology 1993;0(03):-
Objective To analyze the distribution of key target sites(KTSs) during initial circumferential pulmonary vein isolation(CPVI) for atrial fibrillation(AF) and during re-ablation.Methods Forty eight cases(30 males,average age 54.3?10.2 years) with recurrent AF were enrolled.AF was paroxysmal in 24 cases and persistent in 24 cases.Re-ablation was performed 37.2?7.4 days after initial CPVI.KTS was defined as the target sites where pulmonary vein potentials(PVPs) delayed,conduction sequence changed,PVPs slowed down or PV isolated during ablation.Circumferential pulmonary vein(PV) lesions were divided eaqually into 8 segments.KTSs were analyzed during initial CPVI and re-ablation.Results One hundred and forty five KTSs were identified during initial CPVI.The mean KTSs per case were 3.02?1.08,compared with 1.58?1.09 during re-ablation,P
9.Electrophysiological mechanisms of early recurrence of atrial tachyarrhythmias and re-ablation after initial ablation for paroxysmal atrial fibrillation
Xinhua WANG ; Xu LIU ; Haifeng SHI
Chinese Journal of Interventional Cardiology 2003;0(05):-
Objective To evaluate the electrophysiological mechanism of early recurrence of atrial tachyarrhythmias(ATa) after initial ablation for paroxysmal atrial fibrillation(AF)and the feasibility of early re-ablation.Methods Forteen cases(8 males,average age of 61.8?8.4 years) presented with early recurrent ATa within 1 month after initial ablation were included.Early recurrence was observed after a mean of 4.9?3.7 days post-ablation.During re-ablation,all pulmonary vein(PV) reconnection was re-isolated,and AF induction was applied to map and ablate non-PV triggers.ECG and Holter monitor was applied to evaluate the effect.Results Re-ablation was performed after a mean follow-up of 24.7?5.5 days after the first ablation.PV re-connection was identified in 13 cases(92.9%) and was re-isolated by closing conduction gaps along initial lesion lines.By AF induction,superior vena cava(SVC) originated AF was detected in 3 cases and was terminated by SVC isolation.Upper crista terminalis(CT) foci was found in 1 case which was eliminated by focal ablation.Typical atrial flutter(AFL) in 3 cases and left atrial AFL in 1 case were terminated by linear ablation.At the end of follow-up of 5.8?1.4 months,13 cases were free from ATa recurrence and anti-arrhythmic drugs.Paroxymal ATa was observed in 1 case which could be suppressed by verapamil.Conclusion PV re-connection is the main influencing factor of early recurrence of ATa after initial ablation for paroxysmal AF.Other factors include foci located in SVC and CT.Early re-ablation is feasible and effective.
10.Catheter ablation for the treatment of atrial fibrillation:transition of complications throughout learning curve
Xinhua WANG ; Xu LIU ; Haifeng SHI
Chinese Journal of Interventional Cardiology 1993;0(03):-
Objective To analyze the prevalence of complications following catheter ablation for atrial fibrillation and to describe the characteristics of transition of complications.Methods From October 2004 to December 2008,2 260 cases(1 265 males)with atrial fibrillation(AF)were admitted for catheter ablation.AF was paroxysmal in 1 449 cases and chronic in 811 cases.Circumferential pulmonary vein isolation(CPVI)was carried out alone for paroxysmal AF and in combination with fractionated electrograms ablation for chronic AF.Complications were summarized and analyzed by dividing the whole duration into three sections:Year 2004-2006,Year 2007 and Year 2008.Results Complications occurred in 61 cases(2.70%).Cardiac tamponade developed in 11 cases,embolism in 18 cases,pulmonary vein stenosis in 14 cases,and vessel access related complications in 18 cases.In Year 2004-2006,cardiac tamponade occurred in 5 cases,cerebral embolism in 3 cases,mesenteric artery embolism in 1 case,pulmonary vein stenosis in 6 cases,and vessel access related complications in 6 cases.In Year 2007,cardiac tamponade occurred in 4 cases,cerebral embolism in 3 cases,Mesenteric artery embolism in 1 case,pulmonary vein stenosis in 4 cases,and vessel access related complications in 5 cases.In Year 2008,cardiac tamponade occurred in 2 cases,cerebral embolism in 7 cases,mesenteric artery embolism in 3 cases,pulmonary vein stenosis in 4 cases,and vessel access related complications in 7 cases.There was no significant difference in the prevalence of complications among three sections.The prevalence of cardiac tamponade was lower in Year 2008 compared with that in the other two sections,P=0.5.However,the prevalence of embolism was higher in Year 2008 compared with that in the other two the sections,P=0.2.Conclusion It is safe to perform catheter ablation for the treatment of AF.Despite the improvement of technical skills,the prevalence of severe complications such as cardial tamponade,pulmonary vein stenosis or stroke did not decrease.