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Regeneration, relying mainly on resident adult stem cells, is widespread. However, the mechanism by which stem cells initiate proliferation during this process in vivo is unclear. Using planarian as a model, we screened 46 transcripts showing potential function in the regulation of local stem cell proliferation following 48 h regeneration. By analyzing the regeneration defects and the mitotic activity of animals under administration of RNA interference (RNAi), we identified factor for initiating regeneration 1 (Fir1) required for local proliferation. Our findings reveal that Fir1, enriched in neoblasts, promotes planarian regeneration in any tissue-missing context. Further, we demonstrate that DIS3 like 3'-5' exoribonuclease 2 (Dis3l2) is required for Fir1 phenotype. Besides, RNAi knockdown of Fir1 causes a decrease of neoblast wound response genes following amputation. These findings suggest that Fir1 recognizes regenerative signals and promotes DIS3L2 proteins to trigger neoblast proliferation following amputation and provide a mechanism critical for stem cell response to injury.
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Objectives: To analyze the relationship between cardiac troponin I autoantibody (cTnIAAb) and left ventricular remodeling in patients with acute myocardial infarction (AMI). Methods: A total of 131 AMI patients were enrolled. Serum levels of cTnIAAb were measured by ELISA. Echocardiography was examined at the onset of AMI and 1 year follow-up evaluation. Taking left ventricular end systolic volume (LVESV) increasing>15% as left ventricular remodeling, 2-classified logistic stepwise regression analysis was conducted to screen 12 risk factors related to left ventricular remodeling. Results: 23/131(17.6%) patients were with positive cTnIAAb and 82.4% with negative cTnIAAb. 49 patients lost contact and in the rest 91 patients, 21.1% were with positive cTnIAAb. Clinical information was similar between cTnIAAb positive and negative patients upon admission, P>0.05; echocardiography showed that 28 (42.2%) patients had LVESV increasing>15% by 1 year follow-up study whom including 10 (52.6%) patients with cTnIAAb positive and 18 (25.4%) negative. 2-classified logistic stepwise regression analysis indicated that BNP peak and positive cTnIAAb were the risk factors for left ventricular remodeling (OR=1.001, 95% CI 1.001-1.002) and (OR=3.552, 95% CI 1.148-10.989), both P=0.028. Conclusions: Serum cTnIAAb was positive in part of AMI patients which was related to increased risk of left ventricular remodeling; cTnIAAb might be involved in pathophysiological process of left ventricular remodeling in AMI patients.
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Objective To introduce a self-developed left atrial appendage occluder,LACBES,and to explore the clinical feasibility of using it for the occlusion of left atrial appendage (LAA).Methods Eight healthy canines were used in this experimental study.The LAA of each canine was occluded with LACBES occluder through trans-femoral vein approach.After the procedure of occlusion,the compression ratio of the occluder was calculated,the residual shunt was assessed by left atrial angiography.The left atrium pressure was monitored before and after the procedure,and the immediate effect of LAA occlusion on the left atrium pressure was statistically analyzed.Results Implantation of LACBES occluder was successfully accomplished in all the eight canines.The compression ratio of the occluders ranged from 10% to 15%.Small amount of postoperative residual shunt was detected in one canine.After occlusion two canines died of procedure-related complications,including shifting of occluder and formation of hematoma at puncturing site.No device-associated death occurred.After occlusion,the left atrial systolic pressure increased instantly,which went up from preoperative (25.4±2.8) mmHg to postoperative (27.5±3.4) mmHg (P<0.05),but it returned to the baseline of (25.4±2.8) mmHg within 15 minutes.Conclusion For the occlusion of LAA,the use of LACBES occluder carries higher instant success rate and lower residual shunt rate with less device-associated complications,although the left atrial systolic pressure has a transient rising immediately after the occlusion.Therefore,it is expected that LACBES will be able to be applied in clinical practice.
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<p><b>BACKGROUND</b>Permanent atrial fibrillation (AF) is the most common form of dysrhythmia associated with atrial septal defects (ASDs) in patients older than 40 years. However, little is known about cardiac remodeling after transcatheter closure in patients with permanent AF. This study was designed to compare cardiac events and remodeling effects after transcatheter closure in such patients.</p><p><b>METHODS</b>Clinical data of 289 adult patients older than 40 years who underwent ASD closure at our center were analyzed retrospectively. Of them, 63 patients with permanent AF were assigned to the case group, and the other 226 patients without permanent AF were assigned to the control group. Cardiac events and changes in left and right cardiac cavity dimensions before the procedure and 6 months after the procedure were compared between the two groups.</p><p><b>RESULTS</b>Patients in the case group were significantly older than those in the control group. The right ventricular (RV) volume and right atrial (RA) volume were decreased significantly in both the groups during a median follow-up period of 6 months after closure (P < 0.001). The left atrial dimensions, left ventricular end-systolic dimensions, left ventricular end-diastolic dimensions and left ventricular ejection fraction showed no significant change before and after the procedure in both the groups. Changes of the RV volume and RA volume in the case group were significantly smaller than those in the control group (P = 0.005 and P < 0.001). The New York Heart Association cardiac function was improved in both the groups during the 6 months follow-up period.</p><p><b>CONCLUSIONS</b>The transcatheter closure of ASD can improve the cardiac remodeling and cardiac function in patients with or without AF.</p>
Subject(s)
Aged , Aged, 80 and over , Female , Humans , Male , Middle Aged , Atrial Fibrillation , Therapeutics , Cardiac Catheterization , Methods , Heart Septal Defects, Atrial , Therapeutics , Retrospective StudiesABSTRACT
<p><b>BACKGROUND</b>Lack of fluoroscopic landmarks can make valve deployment more difficult in patients with absent aortic valve (AV) calcification. The goal of this article was to evaluate the feasibility and effectiveness of transcatheter implantation of a valved stent into the AV position of a goat, assisted with a microcatheter which provides accurate positioning of coronary artery ostia to help valved stent deployment.</p><p><b>METHODS</b>The subjects were 10 healthy goats in this study. A microcatheter was introduced into the distal site of right coronary artery (RCA) through femoral artery sheath. A minimal thoracic surgery approach was used to access the apex of the heart. The apex of the left ventricle was punctured; a delivery catheter equipped with the valved stent was introduced over a stiff guidewire into the aorta arch. We could accurately locate the RCA ostia through the microcatheter placed in the RCA under fluoroscopy. After correct valve position was confirmed, the valved stent was implanted after rapid inflation of the balloon. The immediate outcome of the function of the valved stents was evaluated after implantation.</p><p><b>RESULTS</b>All ten devices were successfully implanted into the AV position of the goats. Immediate observation after the procedure showed that the valved stents were in the desired position after implantation by angiography, echocardiogram. No obstruction of coronary artery ostia occurred, and no moderate to severe aortic regurgitation was observed.</p><p><b>CONCLUSIONS</b>When the procedure of transcatheter implantation of a balloon-expandable valved stent into the AV position of goats is assisted with microcatheter positioning coronary artery ostia, the success rate of operation can be increased in those with noncalcified AV.</p>
Subject(s)
Animals , Female , Male , Aortic Valve , General Surgery , Goats , Heart Valve Prosthesis Implantation , Methods , Transcatheter Aortic Valve Replacement , MethodsABSTRACT
<p><b>OBJECTIVE</b>To evaluate the safety and efficacy of transcatheter closure of ruptured aneurysm of the sinus of Valsalva (RAVS) using a domestic made small-waist ventricular septal defect occluder.</p><p><b>METHODS</b>Between September 2005 and December 2010, transcatheter closure of RAVS was randomly performed in 7 patients of (43.5 ± 13.0) years old using domestic made small-waist ventricular septal defect occluder in our department. RAVS was diagnosed by color Doppler echocardiography. The size of the small-waist double-disk occlude selected was 4 to 6 mm larger than the narrowest diameter of the opening of aneurysm. After establishment of the arteriovenous wire loop, the device was deployed by retrograde venous approach in all patients. All patients were followed up in terms of rhythm change, residual shunt, shape of occlude, and possible valve regurgitation by echocardiography for 6 to 12 months.</p><p><b>RESULTS</b>All RAVS were confirmed by aortography. Aortography showed rupture of right coronary sinus into the right ventricle in 6 patients and non-coronary sinus ruptured into right ventricle in another patient. The estimated size of the defect was 4 to 7 (5.0 ± 1.3) mm by aortogram. Ventricular septal defect was evidenced in 2 patients. All defects were successfully occluded without complication. Two patients with ventricular septal defect received combined percutaneous ventricular septal defect closure. After transcatheter RAVS occlusion, pulmonary artery systolic pressure decreased from (35.6 ± 12.7) mm Hg (1 mm Hg = 0.133 kPa) to (27.4 ± 6.2) mm Hg (P < 0.05), and mean pulmonary artery pressure decreased from (21.9 ± 8.0) mm Hg to (16.1 ± 5.3) mm Hg (P < 0.05). Cardiac murmur disappeared right after successful occlusion. Echocardiography detected a trace of residual shunt in one patient after occlusion which disappeared the next day. There was no aortic regurgitation, hemolysis and arrhythmia during hospitalization. There was no device embolization, infective endocarditis, right heart failure and death during the 6 to 12 months follow-up.</p><p><b>CONCLUSION</b>Transcatheter closure of RAVS with the domestic made small-waist ventricular septal defect occluder is safe and effective.</p>
Subject(s)
Adult , Aged , Female , Humans , Male , Middle Aged , Young Adult , Aneurysm, Ruptured , General Surgery , Cardiac Catheterization , Methods , Heart Aneurysm , Septal Occluder Device , Sinus of Valsalva , Pathology , Treatment OutcomeABSTRACT
<p><b>BACKGROUND</b>Off-label application of drug-eluting stents (DES) during percutaneous coronary intervention (PCI) was not uncommon in daily practice, however DES in treating Chinese patients with complex lesion subset was under-investigated. The primary objective of the FIREMAN registry was to evaluate the long term efficacy and safety of the Firebird sirolimus-eluting stent (SES) in treating patients with complex coronary lesions. Here we report the mid-term of one-year clinical outcomes and eight-month angiographic follow-up results of FIREMAN registry.</p><p><b>METHODS</b>The FIREMAN registry was a prospective multi-center registry, which included 1029 consecutive patients undergoing PCI with Firebird SES implantation between September 2006 and July 2007 in 45 centers in China. The clinical follow-up was designed to be performed at 1, 6, 12, 18, 24, 30 and 36 months post index procedure, and non-mandatory angiographic follow-up at 8 months was planned. One hundred percent site monitoring was conducted.</p><p><b>RESULTS</b>Long lesions (59.2%), multi-vessel disease (50.4%), and small vessel disease (31.6%) were mostly found in angiography. Major adverse cardiac events (MACE) occurred in 51 (5.1%) patients at 1 year clinical follow-up, including cardiac mortality in 6 (0.6%), non-fatal myocardial infarction in 11 (1.1%), and target lesion revascularization in 36 (3.5%) of the patients. Definite and probable stent thrombosis (ST) by Academic Research Consortium (ARC) definition occurred in 12 (1.36%) patients at one-year clinical follow-up. The 8-month binary restenosis rate was 5.7% in-segment and 4.3% in-stent, respectively. Late lumen loss was (0.21 ± 0.40) mm in-segment and (0.23 ± 0.36) mm in-stent, respectively. Furthermore, Cox regression analysis revealed that diabetes, small vessel diameter, and chronic total occlusion were independent predictors of ST.</p><p><b>CONCLUSIONS</b>The results showed that the Firebird SES was effective and safe in treating Chinese patients with complex coronary lesions and occurrence of ST rate at one-year clinical follow-up was acceptable, however further long-term follow-up was still necessary. (NCT00552656)</p>
Subject(s)
Aged , Female , Humans , Male , Middle Aged , Angioplasty, Balloon, Coronary , Methods , Asian People , Coronary Angiography , Coronary Disease , Diagnostic Imaging , Therapeutics , Drug-Eluting Stents , Prospective Studies , Sirolimus , Therapeutic Uses , Treatment OutcomeABSTRACT
<p><b>OBJECTIVE</b>To investigate the role of miRNA-199a on cardiac hypertrophy.</p><p><b>METHODS</b>(1) Male Sprague-Dawley rats were subjected to pressure overload induced by abdominal aortic constriction (AAC, n = 6) and quantitative real-time polymerase chain reaction (qRT-PCR) was used to detect the change of microRNAs (miRNAs). (2) Neonatal rat ventricular myocytes were isolated from 2-day old Sprague-Dawley rats. The myocytes were divided into two groups: adenovirus miRNA-199a (Ad-miRNA-199a) or adenovirus vector (Ad-vector). They were transfected in cardiomyocytes for 48 h using Lipofectamine 2000. qRT-PCR was used to detect the change of myocardial hypertrophy markers α-myosin heavy chain (αMHC, myh6), β-myosin heavy chain (βMHC, myh7) and atrial natriuretic peptide (ANP, Nppa). Software Axio Vision was used to detect the change of cardiomyocytes surface areas. (3) Neonatal rat ventricular myocytes were divided into two groups: antisense oligonucleotide-miRNA-199a (As-miRNA-199a) and scramble oligonucleotides (As-ctl). They were transfected to cardiomyocytes respectively for 48 h. qRT-PCR was used to detect the change of miRNA-199a. (4) Neonatal rat ventricular myocytes were divided into four groups: A: control (ctl), B: phenylephrine (PE), C: PE + As-ctl, D: PE + As-miRNA-199a. qRT-PCR was used to detect the change of myh6, myh7 and Nppa. Software Axio Vision was used to detect the change of cardiomyocytes surface areas.</p><p><b>RESULTS</b>(1) qRT-PCR results showed that miRNA-1, miRNA-133, miRNA-181a and miRNA-499 were significantly decreased, while the miRNA-199a was significantly increased at 1 week post AAC hearts compared with the sham group. (2) qRT-PCR results showed that miRNA-199a and myh7 were increased and myh6 was decreased significantly in Ad-miRNA-199a group compared with Ad-vector group. The cardiomyocytes surface area was increased in Ad-miRNA-199a group detected by immunofluorescence. (3) qRT-PCR results showed that miRNA-199a was significantly decreased in As-miRNA-199a group compared with Ad-vector group. (4) The Nppa and myh7 were significantly increased and myh6 was decreased in cardiomyocytes stimulated by PE for 48 h. The cardiomyocytes surface area determined by immunofluorescence was increased in PE + As-miRNA-199a groups compared with PE + As-ctl groups.</p><p><b>CONCLUSION</b>miRNA-199a may play a regulatory role in cardiac hypertrophy.</p>
Subject(s)
Animals , Male , Rats , Animals, Newborn , Atrial Natriuretic Factor , Metabolism , Cardiomegaly , Metabolism , Pathology , MicroRNAs , Myosin Heavy Chains , Metabolism , RNA, Messenger , Genetics , Rats, Sprague-DawleyABSTRACT
<p><b>BACKGROUND</b>Pulmonary regurgitation leads to progressive right ventricular dysfunction, susceptibility to arrhythmias, and sudden cardiac death. Percutaneous valve replacement has been developed in recent years, providing patients with an alternative option. Percutaneous pulmonary valve replacement has been recently introduced into clinical practice. The goal of this study was to evaluate the feasibility of percutaneous valve stent insertion to correct the pulmonary regurgitation in sheep using a cup-shaped valve stent.</p><p><b>METHODS</b>Pulmonary regurgitation was created by percutaneous cylindrical stent insertion in native pulmonary annulus of 8 sheep. One month after the initial procedure, the sheep with previous cylindrical stent implanted underwent the same implantation procedure of pulmonary valve stent. The valve stent consisted of a cup-shaped stent and pericardial valves. Hemodynamic assessments of the bioprosthetic pulmonary valve were obtained by echocardiography at immediately post-implant and at 2 months follow up.</p><p><b>RESULTS</b>Successful transcatheter cylindrical stent insertion was performed in 7 sheep but failed in 1 sheep because the cylindrical stent was released to right ventricle outflow tract. After one month the 7 sheep with pulmonary regurgitation underwent valve stent implantation successfully. Echocardiography confirmed the stents were in desired position during the follow-up. No evidence of pulmonary valve insufficiency occurred in any animals. Echocardiography showed all heart function markers were normal.</p><p><b>CONCLUSIONS</b>Percutaneous cylindrical stent insertion to induce significant pulmonary regurgitation in sheep was feasible, simple and reproducible. Percutaneous pulmonary valve stent implantation can reduce pulmonary regurgitation in a sheep model. Further development of animal model and clinical trials are warranted.</p>
Subject(s)
Animals , Female , Male , Feasibility Studies , Heart Valve Prosthesis , Heart Valve Prosthesis Implantation , Pulmonary Valve Insufficiency , General Surgery , SheepABSTRACT
<p><b>BACKGROUND</b>Valve replacement or repair is recommended in patients with tricuspid regurgitation when deterioration of their clinical status occurs as a consequence of right ventricular dysfunction. Percutaneous valve replacement was developed in recent years. To investigate the feasibility, effectiveness and long-term results of percutaneous tricuspid valve replacement, an experimental model with tricuspid regurgitation is needed. We developed a simple and reproducible percutaneous approach for the creation of tricuspid regurgitation in sheep.</p><p><b>METHODS</b>A specially designed grasping forceps were used to grasp chordae tendineae or the tricuspid valve leaflets through a catheter. Transcatheter creation of tricuspid regurgitation was performed on 7 healthy sheep. These sheep were followed up shortly after the procedure and at 6th month post-procedure with echocardiography. Additionally, all the sheep were sacrificed for anatomic evaluation at 6th month after the procedure.</p><p><b>RESULTS</b>Creation of tricuspid regurgitation was successfully accomplished in all sheep. Necropsy confirmed that damage was done to the tricuspid valve apparatus in all animals (tearing of the anterior leaflet of the tricuspid valve in five animals and posterior leaflet of the tricuspid valve in two animals). At the six-month follow-up, there was no significant increase in the right ventricle dimension and ejection fraction measured by echocardiography. Autopsy examinations demonstrated the tearing of tricuspid valve leaflets.</p><p><b>CONCLUSIONS</b>The creation of an animal model of tricuspid regurgitation via a percutaneous approach using forceps to sever one or more tricuspid leaflets is feasible and will allow investigation of devices designed replace the tricuspid valve via a percutaneous approach. Despite significant tricuspid regurgitation, the hemodynamics did not change during the follow-up period in this model.</p>
Subject(s)
Animals , Female , Male , Catheterization , Disease Models, Animal , Echocardiography , Heart Valve Prosthesis Implantation , Methods , Sheep , Tricuspid Valve Insufficiency , TherapeuticsABSTRACT
<p><b>OBJECTIVE</b>To evaluate the efficacy and adverse effects of transcatheter closure of perimembranous ventricular septal defect (pmVSD) with modified double-disk occluder device (MDVO).</p><p><b>METHODS</b>Clinical data including clinical examination, electrocardiography daily after the procedure for a week, chest-X-rays and TTE before discharge and at 3-5 days after the procedure were analyzed from 604 patients underwent percutaneous closure of a pmVSD with MDVO at our department between December 2001 and December 2008.</p><p><b>RESULTS</b>Procedure was successful in 576 out of 604 patients (95.4%) and 583 VSD occluders were placed. Endocarditis, thromboembolism, or deaths were not observed after procedure. Conduction block occurred in 81 patients (56 RBBB, 14 LBBB) and transient nonparoxysmal ventricular tachycardia in 31 patients after the procedure. Complete heart block occurred in 11 patients, 9 of them recovered in 3 weeks, permanent pacemaker was implanted in 2 patients (one had transient III degrees AVB before the procedure, the other underwent simultaneous closure of ventricular septal defect and atrial septal defect). Trivial/small residual shunts were found in 69 patients (12.0%). The residual shunts disappeared in 31 patients and remained unchanged in 38 patients (6.6%) 7 days after procedures. Aortic regurgitation developed in 5 patients (2 trivial/small, 3 small/moderate), and tricuspid regurgitation was present in 35 patients (32 trivial/small, 3 moderate). Five patients developed haemolysis (device retrieved via catheter in 1 patient due to persistent haemolysis, the other 4 patients recovered 3-14 days post procedure). Pseudoaneurysm of femoral artery occurred in 1 patient, and disappeared by pressure dressing. Device was successfully replaced in 2 patients with either device embolization (n = 1) or device misplacement (n = 1) after device retrieval by catheter.</p><p><b>CONCLUSION</b>It is safe and effective to close congenital perimembranous ventricular septal defect with domestic-made occluder device.</p>
Subject(s)
Adolescent , Adult , Aged , Child , Child, Preschool , Female , Humans , Infant , Male , Middle Aged , Young Adult , Balloon Occlusion , Cardiac Catheterization , Echocardiography , Heart Septal Defects, Ventricular , Therapeutics , Treatment OutcomeABSTRACT
<p><b>BACKGROUND</b>Percutaneous aortic valve replacement is a promising strategy in the treatment of patients with aortic valve stenosis. And many kinds of valved stents have been implanted in selected patients worldwide. However, the clinical experience is still limited. We developed a W-model valved stent and evaluated the feasibility and safety of percutaneous implantation of the device in the native aortic valve position.</p><p><b>METHODS</b>A self expanding nitinol stent with W-model, containing porcine pericardium valves in its proximal part, was implanted in six sheep by means of a 14 French catheter through the right common iliac artery under guidance of fluoroscopy. During stent deployment the original aortic valve was pushed against the aortic wall by the self expanding force of the stent while the new valve was expanded. These sheep were followed up shortly after procedure with supra-aortic angiogram and left ventriculography. Additionally, one sheep was sacrificed after the procedure for anatomic evaluation.</p><p><b>RESULTS</b>It was possible to replace the aortic valve in the beating heart in four sheep. The procedure failed in two sheep due to coronary orifice occlusion in one case and severe aortic valve regurgitation in the other case. One sheep was killed one hour after percutaneous aortic valve replacement for anatomic evaluation. There were no signs of damage of the aortic intima, or of obstruction of the coronary orifice.</p><p><b>CONCLUSIONS</b>Percutaneous aortic valve replacement with a W-model valved stent in the beating heart is possible. Further studies are mandatory to assess safety and efficacy of this kind of valved stent in larger sample size and by longer follow-up period.</p>
Subject(s)
Animals , Female , Male , Aortic Valve , Pathology , General Surgery , Aortic Valve Stenosis , General Surgery , Feasibility Studies , Fluoroscopy , Heart Valve Prosthesis Implantation , Methods , Sheep , StentsABSTRACT
<p><b>OBJECTIVE</b>To evaluate the efficacy and safety of a fixed dose combination of telmisartan 80 mg plus hydrochlorothiazide (HCTZ) 12.5 mg (TH) to telmisartan 80 mg (T) in Chinese patients who failed to respond adequately to treatment with T.</p><p><b>METHOD</b>This is a multi-center, randomized, double-blind, double-dummy clinical study. A total of 699 eligible hypertensive patients entered a one-week screening phase prior to the eight-week open-label T period. At the end of eight weeks, 345 patients who failed to respond to T (DBP > or = 90 mm Hg, 1 mm Hg = 0.133 kPa) were randomized to receive either TH (175 patients) or T (170 patients) for another eight weeks. Sitting and standing BP were taken 24 hours post-dose and adverse events were documented at visit with 4 weeks interval. Laboratory, ECG and physical examination were performed at screening, at baseline and at the final visit.</p><p><b>RESULTS</b>After 8 weeks treatment, (1) The mean trough reduction in sitting diastolic blood pressure (SiDBP) from baseline in TH group was greater than that in T group (10.1 mm Hg vs 7.7 mm Hg, P = 0.0017). The mean trough reduction in sitting systolic blood pressure (SiSBP) from baseline was 14.2 mm Hg in TH group and 7.4 mm Hg in T group (P < 0.0001). (2) The mean trough reduction in standing DBP and standing SBP from baseline were significantly greater in TH group (8.7 mm Hg and 12.9 mm Hg) compared those in T group (7.3 mm Hg and 7.0 mmHg, P = 0.0350, P < 0.0001). (3) The number and percentage of responders in TH group (129, 74.6%) were significantly higher than in T group (100, 59.2%, P = 0.0016). (4) The incidence of the study drug-related adverse events was similar between TH and T group (3.5% vs. 3.6%, P > 0.05).</p><p><b>CONCLUSION</b>TH was more effective than T in patients not responded adequately to T in Chinese hypertensive patients.</p>
Subject(s)
Adult , Aged , Aged, 80 and over , Female , Humans , Male , Middle Aged , Angiotensin II Type 1 Receptor Blockers , Therapeutic Uses , Benzimidazoles , Therapeutic Uses , Benzoates , Therapeutic Uses , Double-Blind Method , Drug Therapy, Combination , Hydrochlorothiazide , Therapeutic Uses , Hypertension , Drug Therapy , Treatment OutcomeABSTRACT
<p><b>OBJECTIVE</b>The purpose of this study was to determine the feasibility of transcatheter pulmonary valve replacement in sheep up to 6 months post procedure.</p><p><b>METHODS</b>Fresh sheep pericardium treated with a 0.6% glutaraldehyde solution for 36 hours was sutured to a valvular ring and then fixed onto a newly designed nitinol self-expandable stent. Thoracotomy was performed in sheep (23.5 +/- 3.1) kg under general anesthesia and the device was delivered into the native pulmonary valve of the sheep via the anterior wall of right ventricle by catheter and fooled for 6 months.</p><p><b>RESULTS</b>One sheep died 4 months after the procedure due to in-stent thrombosis. Another 4 animals survived the 6-month observing period. Angiographic and hemodynamic measurements confirmed good positioning and function of the stents with a competent valve immediately post procedure and 6 months post the procedure in surviving animals.</p><p><b>CONCLUSION</b>Implantation of the nitinol self-expandable stent in the pulmonary valve position by a transcatheter approach is feasible and good function of transcatheter implanted memory nitinol valved stents was shown after 6 months of implantation in sheep.</p>
Subject(s)
Animals , Female , Male , Disease Models, Animal , Heart Valve Prosthesis , Heart Valve Prosthesis Implantation , Methods , Pulmonary Valve , General Surgery , Sheep , StentsABSTRACT
<p><b>BACKGROUND</b>Recent studies have showed that the fine mesh stents are associated with a significant reduction in both clinical and angiographic re-stenosis of the coronary arteries. To maintain a very satisfactory radio-opacity using the stents, Guidant of the USA has designed a new type of bare metal stents (BMS)-Multi-link (ML) Vision/ML MiniVision stents. The clinical outcomes of Asian patients with coronary artery disease (CAD) after implanting the Multi-link Vision or MiniVision stent were investigated in this study.</p><p><b>METHODS</b>An observational, prospective, multi-center, non-randomized post marketing registry was conducted to demonstrate the efficacy of the BMS-ML Vision/ML MiniVision stents. The primary end point of the registry was clinical target lesion revascularization (TLR) at a 6-month follow-up. The major secondary end points included the rate of major adverse cardiac events (MACE) and serious adverse events (SAE) in hospital and at 6 months; and the rate of clinical TLR as a function of the type of angina. A total of 429 Asian people with 449 lesions from 14 centers were selected for this study. The average reference diameter of the lesions was (3.0 +/- 0.5) mm, and the mean length was (15.7 +/- 5.0) mm.</p><p><b>RESULTS</b>The successful rate of the procedure was 99.3%. Twenty-five percent of the lesions were treated by direct stenting without pre-dilation. Eighty-six percent of the lesions were implanted with ML Vision stent. After the 6-month follow-up, the rate of clinical TLR was 1.4%. The MACE, SAE and target vessel revascularization (TVR) were 6.8%, 3.5% and 1.4% respectively.</p><p><b>CONCLUSION</b>The current registry showed the excellent 6-month clinical outcomes of ML Vision/ML MiniVision stents in Asian patients with CAD.</p>
Subject(s)
Aged , Female , Humans , Male , Middle Aged , Angioplasty, Balloon, Coronary , Methods , Chromium Alloys , Coronary Disease , Therapeutics , Follow-Up Studies , Prospective Studies , Registries , StentsABSTRACT
Objective To evaluate the safety,biocompatibility and efficacy of transcatheter closure of atrial septal defect(ASD)with no stainless-steel-screw occluder in canine model.Methods The device was constructed from superelastic Nitinol wires tightly woven into two flat disks and sewed with polyester fibers inside,with a pliable loop on the right-atrial-disk of the device,connecting to the delivery cable.ASD was created by transcatheter puncture and balloon dilatation and then closed by occluder under fluoroscopy in the catheterization laboratory.The location and the influence of the implanted device on function of tricuspid valve and mitral valve were evaluated by echocardiography.At 1,2,3 and 6 months after the operation,the animals were killed and autopsy was conducted.Results Eight dogs with puncture-produced ASD underwent ASD closing procedure successfully.The occluder showed no influence on the function of MV and AV demonstrated by echocardiogram.The two disks of the implanted device were covered with a smooth intact neogenesis layer in all dogs.Endocardial cells fully covered the surface of the two disk without inflammating reaction 3 months later. There was no evidence of corrosion on the surface of the nitinol wire removed from the dog after 6 months.Light microscopic examination of the liver,kidney,lung and spleen showed no evidence of embolization and inflammation.Conclusion Transcatheter ASD occlusion with new-type occluder is safe,feasible,effective and good biocompatibility with a good prospective clinical application.
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To investigate the effect of GST-KGDX (glutathione S-transferase-Lys-Gly-Asp-X) fusion protein, GP IIb/IIIa receptor antagonist, on platelet function in vitro. The KGDX (Lys-Gly-Asp-X) gene was assembled from 2 synthetic oligonucleotides, 36 bp in length, using BamH I and Xho I restriction enzyme sites at the end of the gene for cloning into the expression vector pGEX4T-1. Expression of fusion protein was directed by the tac promoter. The Escherichia coli DH5a contained the plasmid pGEX-4T-1-KGDX was expressed by 37 degrees C heat induction. The fusion protein of KGDX with glutathione S-transferase (GST-KGDX) was purified in one step from the bacterial lysate by glutathione-agarose beads for affinity chromatography. GST-KGDX was found to be soluble and abundant, the yield of 35 mg/L of cultures was obtained. The GST-KGDX was expressed in E. coli to a level of 48.02% of total cellular protein. GST-KGDX inhibited ADP-induced human platelet aggregation stronger than GST (P < 0.05 or < 0.01). In flow cytometry assay for fibrinogen binding, both GST and GST-KGDX inhibited platelet aggregation by binding with high affinity to GPIIb/IIIa. Mean fluorescence intensity of GST-KGDX fusion protein was significantly higher than that of GST. It is concluded that the GST-KGDX fusion protein can be produced by E. coli and used as an antiplatelet agent.
Subject(s)
Adult , Female , Humans , Male , Escherichia coli , Genetics , Fibrinogen , Metabolism , Flow Cytometry , Glutathione Transferase , Pharmacology , Oligopeptides , Pharmacology , Platelet Aggregation , Platelet Aggregation Inhibitors , Pharmacology , Platelet Glycoprotein GPIIb-IIIa Complex , Metabolism , Recombinant Fusion Proteins , PharmacologyABSTRACT
Objective: To investigate the effect of human vascular endothelial growth factor on restenosis after angioplasty. Methods: A rabbit model of injured carotid artery was established using percutaneous transluminal angioplasty. The pcDNA3/hVEGF165(500 μg,n=12) and pcDNA3 (500 μg,n=12) were separately transfected into injured arterial wall with 30 min incubation. The carotid artery was imaged by arotic angiography at the end of week 2 and week 4. Pathology analysis and Northern blot analysis were performed for harvested injured artery segment. Results: Arotic angiography showed carotid artery diameter narrowness were obviously lessened at week 2 and week 4 in experimental group than that in control group; H-E stains showed lumina narrow ratio were obviously reduced at week 2 and week 4 in experimental group than that in control group[(9.58±1.35)% vs (31.72±1.72)%;(18.09±2.93)% vs (44.05±3.28)%, P<0.01 ]; By Northern blot analysis, the expression of hVEGF165mRNA in experimental group were upregulated than in contol group. Conclusion: pcDNA3/hVEGF165 can be transfected into smooth muscle cell and continue to secret bioactivity protein at least for 4 weeks; it can accelerate reendothelialization and prevent restenosis.
ABSTRACT
Objective: To investigate the effect of human vascular endothelial growth factor on restenosis after angioplasty. Methods: A rabbit model of injured carotid artery was established using percutaneous transluminal angioplasty. The pcDNA3/hVEGF165(500 μg,n=12) and pcDNA3 (500 μg,n=12) were separately transfected into injured arterial wall with 30 min incubation. The carotid artery was imaged by arotic angiography at the end of week 2 and week 4. Pathology analysis and Northern blot analysis were performed for harvested injured artery segment. Results: Arotic angiography showed carotid artery diameter narrowness were obviously lessened at week 2 and week 4 in experimental group than that in control group; H-E stains showed lumina narrow ratio were obviously reduced at week 2 and week 4 in experimental group than that in control group[(9.58±1.35)% vs (31.72±1.72)%;(18.09±2.93)% vs (44.05±3.28)%, P<0.01 ]; By Northern blot analysis, the expression of hVEGF165mRNA in experimental group were upregulated than in contol group. Conclusion: pcDNA3/hVEGF165 can be transfected into smooth muscle cell and continue to secret bioactivity protein at least for 4 weeks; it can accelerate reendothelialization and prevent restenosis.
ABSTRACT
Objective:To compare the tissue biocompatibility of domestically manufactured NiTi alloy before and after thermal surface oxidation under 3 different temperatures.Methods:Domestically manufactured NiTi alloy was oxidized in air (group A)and subjected to 30 min heat treatment at 400℃(group B),500℃(group C),and 600℃(group D)to form different protective oxide surface layers in presence of argon(607.95 kPa).Wire samples from A,B,C and I3 groups were subcutaneously implanted in guinea pigs.Guinea pigs received 317L stainless steel transplantation(group E)and sham-operation group(F)were taken as control.The order of inflammatory cell infiltration and tissue hyperplasia around implanted materials were observed 1,2,4,and 8 weeks after implantation.Results:The peak time of inflammatory cell infiltration and fibrous hyperplasia were at the first and fourth week after implantation.The inflammatory cell infiltration and fibrous hyperplasia were both slight and all met the GB/T 16886.6-1997 in vivo implantation standard.The order of inflammatory cell infiltration and thickness of capsule walls from low to high was F