Objective:To isolate and identify active constituents from Gracilaria chorda extract prepared under subcritical water conditions at 210℃(GCSW210)and evaluate their anti-obesity and anti-diabetic effects in 3T3-L1 adi...Objective:To isolate and identify active constituents from Gracilaria chorda extract prepared under subcritical water conditions at 210℃(GCSW210)and evaluate their anti-obesity and anti-diabetic effects in 3T3-L1 adipocytes and high-fat diet(HFD)-induced obese zebrafish larvae.Methods:GCSW210 was fractionated through solvent partitioning,ion-exchange chromatography,and silica gel medium-pressure liquid chromatography,followed by preparative high performance liquid chromatography.At each step,bioactivities were assessed in 3T3-L1 adipocytes by Oil Red O staining and 2-NBDG uptake assays.The most active fractions were further purified,and isolated compounds were tested in HFD-induced obese zebrafish larvae.Results:Liquid chromatography-hyphenated analysis with reference standards identified two major compounds in GCSW210:5-hydroxymethylfurfural and bis(5-formylfurfuryl)ether.Both compounds significantly inhibited lipid accumulation in 3T3-L1 adipocytes and modulated gene expression associated with adipogenesis,glucose metabolism,and inflammation in zebrafish.They also enhanced glucose uptake,reduced circulating glucose levels,and improved insulin sensitivity.Notably,the effects were comparable to those of the crude GCSW210 extract.In silico docking studies confirmed stable interactions of both compounds with key metabolic and inflammatory targets,with bis(5-formylfurfuryl)ether showing stronger binding affinities.Conclusions:These findings suggest that 5-hydroxymethylfurfural and bis(5-formylfurfuryl)ether are key contributors to the therapeutic activity of Gracilaria chorda,highlighting its potential as a functional food ingredient for the prevention or management of metabolic disorders.展开更多
BACKGROUND The off-label use of various devices has been reported for the transcatheter closure of perimembranous ventricular septal defects(PmVSD) because of serious complications, such as heart block and tricuspid r...BACKGROUND The off-label use of various devices has been reported for the transcatheter closure of perimembranous ventricular septal defects(PmVSD) because of serious complications, such as heart block and tricuspid regurgitation(TR),associated with conventional ventricular septal defect devices. However, whether certain defects such as PmVSD with abnormally attached tricuspid are fit for interventional treatment is still disputable.AIM To explore the feasibility and safety of transcatheter closure of PmVSD with abnormally attached tricuspid chordae tendineae using an improved patent ductus arteriosus(PDA) occluder.METHODS We retrospectively analyzed 20 patients diagnosed with PmVSD with abnormally attached tricuspid chordae tendineae who underwent interventional treatment using an improved PDA occluder at our center from January 2012 to January 2016. Baseline characteristics and procedural and follow-up data were analyzed.RESULTS All 20 patients achieved procedure success. No heart block occurred during the operation. One patient had a transient complete right bundle branch block within48 h post-procedure and reverted to normal rhythm after intravenous injections of dexamethasone for 3 d. For all 20 patients, no residual shunt was observed by transthoracic echocardiography post-procedure. During the average follow-up period of 2.4 years, no severe TR was observed.CONCLUSION Using of the improved PDA occluder for the transcatheter closure of PmVSD with abnormally attached tricuspid chordae tendineae is a safe and promising treatment option. However, long-term follow-up in a large group of patients is still warranted.展开更多
Background: Recently, the concept of “Respect rather than resect” has been proposed in an attempt to restore mitral valve function. We investigated the results of mitral valve repair for posterior leaflet disease. M...Background: Recently, the concept of “Respect rather than resect” has been proposed in an attempt to restore mitral valve function. We investigated the results of mitral valve repair for posterior leaflet disease. Methods: Between April 2008 and July 2017, mitral valve repair was performed in 78 cases at our facility. Among them, 37 cases were analyzed. We divided patients into three groups according to the repair techniques used: artificial chordae technique, which uses the anchoring-technique and measured tube technique (Group A, 23 cases), resection and suture technique (Group R, 10 cases), and artificial chordae together with resection and suture technique (Group AR, 4 cases), and compared their postoperative outcomes. Results: Residual postoperative mitral regurgitation (MR) grade in groups A, R and AR at discharge were 0.3 ± 0.4, 0.8 ± 0.9 and 0.0 ± 0.0 (p = 0.07), respectively. Mitral valve areas (cm2) in groups A, R and AR were 3.2 ± 0.6, 2.9 ± 0.6 and 3.0 ± 0.6 (p = 0.47), respectively. Freedom from severe MR at 5 years postoperatively was seen in 91.7%, 90% and 100% (p = 0.92) in groups A, R and AR, respectively. Conclusions: There was no significant difference in postoperative outcomes, as assessed echocardiographically, between the artificial chordae technique and resection and suture technique. The results of all repair techniques were satisfactory.展开更多
BACKGROUND Mitral valvuloplasty using artificial chordae tendineae represents an effective surgical approach for treating mitral regurgitation.Achieving precise measurements of artificial chordae tendineae length(CL)i...BACKGROUND Mitral valvuloplasty using artificial chordae tendineae represents an effective surgical approach for treating mitral regurgitation.Achieving precise measurements of artificial chordae tendineae length(CL)is an important factor in the procedure;however,no objective index currently exists to facilitate this measurement.Therefore,preoperative assessment of CL is critical for surgical planning and support.Four-dimensional x-ray micro-computed tomography(4D-CT)may be useful for accurate CL measurement considering that it allows for dynamic three-dimensional(3D)evaluation compared to that with transthoracic echocardiography,a conventional inspection method.AIM To investigate the behavior and length of mitral chordae tendineae during systole using 4D-CT.METHODS Eleven adults aged>70 years without mitral valve disease were evaluated.A 64-slice CT scanner was used to capture 20 phases in the cardiac cycle in electrocardiographic synchronization.The length of the primary chordae tendineae was measured from early systole to early diastole using the 3D image.The primary chordae tendineae originating from the anterior papillary muscle and attached to the A1-2 region and those from the posterior papillary muscle and attached to the A2-3 region were designated as cA and cP,respectively.The behavior and maximum lengths[cA(ma),cP(max)]were compared,and the correlation with body surface area(BSA)was evaluated.RESULTS In all cases,the mitral anterior leaflet chordae tendineae could be measured.In most cases,the cA and cP chordae tendineae could be measured visually.The mean cA(max)and cP(max)were 20.2 mm±1.95 mm and 23.5 mm±4.06 mm,respectively.cP(max)was significantly longer.The correlation coefficients(r)with BSA were 0.60 and 0.78 for cA(max)and cP(max),respectively.Both cA and cP exhibited constant variation in CL during systole,with a maximum 1.16-fold increase in cA and a 1.23-fold increase in cP from early to mid-systole.For cP,CL reached a plateau at 15%and remained elongated until end-systole,whereas for cA,after peaking at 15%,CL shortened slightly and then moved toward its peak again as end-systole approached.CONCLUSION The study suggests that 4D-CT is a valuable tool for accurate measurement of both the length and behavior of chordae tendineae within the anterior leaflet of the mitral valve.展开更多
BACKGROUND As left bundle branch pacing(LBBP)is more like physiological pacing,LBBP has emerged as a novel pacing strategy that uses the native conduction system to improve ventricular synchronization with stable paci...BACKGROUND As left bundle branch pacing(LBBP)is more like physiological pacing,LBBP has emerged as a novel pacing strategy that uses the native conduction system to improve ventricular synchronization with stable pacing parameters.LBBP has been revealed associated with a significantly reduced risk of new-onset atrial fibrillation and heart failure compared with conventional permanent pacemaker implantation.CASE SUMMARY A 64-year-old man was admitted with a 24-h history of chest distress and shortness of breath,which continued unabated.The patient had no symptoms of chest pain,dizziness,syncope,nausea nor vomiting.There were no abnormalities found in routine examinations after admission.Twelve-lead electrocardiogram presented a result of 2:1 atrioventricular block.Coronary angiography was performed the next day and no abnormality was found.Finally,the patient agreed to received LBBP and signed the informed consent.During the process of withdrawing the Medtronic Model 3830 lead into sheath,we found the lead helix was wrapped around the chordae tendineae of the septal valve of tricuspid.Attempts to rotate the 3830 lead failed to release the lead helix from the chordae tendineae,and ultimately we used radiofrequency ablation to ablate the wrapped chordae tendineae.CONCLUSION Radiofrequency ablation effectively solved this problem without complications.It is an effective and reliable method to resolve lead winding chordae.展开更多
Objective To investigate the surgical technique and outcomes of replacement of chordae tendineae in mitral valve repair,and evaluate the value of real-time three-di-mensional transesophageal echocardiography in the pe...Objective To investigate the surgical technique and outcomes of replacement of chordae tendineae in mitral valve repair,and evaluate the value of real-time three-di-mensional transesophageal echocardiography in the perioperative period. Methods Thirty-one patients with mitral valve prolapse underwent mitral valve repair using chordae tendineae replacement concomitant with implantation展开更多
Surgical repair with artificial chordae replacement has emerged asa standard treatment for mitral regurgitation. Expanded polytetrafluoroethylene (ePTFE) sutures are commonly employed asartificial chordae;however, the...Surgical repair with artificial chordae replacement has emerged asa standard treatment for mitral regurgitation. Expanded polytetrafluoroethylene (ePTFE) sutures are commonly employed asartificial chordae;however, they have certain limitations, such aspotential long-term rupture and undesired material/tissueresponse. This study introduces a novel approach to artificialchordae design, termed the New Artificial Chordae (NAC), whichincorporates a double-layered structure. The NAC comprises amulti-strand braided core composed of ultra-high molecularweight polyethylene (UHMWPE) fibers as the inner core, and anouter tube made of hydrophobic porous ePTFE. Compared totraditional ePTFE sutures, NAC exhibits increased flexibility,enhanced tensile strength, longer elongation and improved fatigue resistance. Moreover, NAC exhibits a more hydrophobic surface,which contributes to enhanced hemocompatibility. The study also includes in vivo investigations conducted on animal models to evaluate the biocompatibility and functional efficacy of the artificial chordae. These experiments demonstrate the enhanced durability andbiocompatibility of the NAC, characterized by improved mechanical strength, minimal tissue response and reduced thrombus formation.These findings suggest the potential application of NAC as a prosthetic chordae replacement, offering promising prospects to address thelimitations associated with current artificial chordae materials and providing novel ideas and approaches for the development of sustainable and biocompatible regenerative biomaterials.展开更多
Artificial chordae replacement with expanded polytetrafluoroethylene （ePTFE; Gore-Tex, W.L.Gore and Associates Inc., Flagstaff, AZ, USA） is an established technique for mitral valve repair with excellent long-term r...Artificial chordae replacement with expanded polytetrafluoroethylene （ePTFE; Gore-Tex, W.L.Gore and Associates Inc., Flagstaff, AZ, USA） is an established technique for mitral valve repair with excellent long-term results. There is growing interest in the application of artificial chordae to correct mitral valve regurgitation caused by anterior leaflet prolapse. Application of pre-measured artificial chordae facilitates creation of chordae with appropriate length. The aim of this study was to illustrate the technique for creation of pre-measured artificial chordae.展开更多
Background： Right minithoracotomy （RM） has been proven to be a sate and effective approach for mitral valve surgery, but the differences of artificial chordae technique between RM and median sternotomy （MS） were ...Background： Right minithoracotomy （RM） has been proven to be a sate and effective approach for mitral valve surgery, but the differences of artificial chordae technique between RM and median sternotomy （MS） were seldom reported. Here, we compared the outcomes of modified artificial chordae technique for mitral regurgitation （MR） through RM or MS approaches. Methods： One hundred and eighteen consecutive adult patients who received mitral valve repair with artificial chordae and annuloplasty for MR through RM （n = 58） or MS （n = 60） from January 2006 to January 2015 were analyzed. Results： All of the selected patients underwent mitral valve repair successfully without any complication during the surgery. There was no significant difference between RM group and MS group in cardiopuhnonary bypass time, aortic cross-clamp time, and early postoperative complications. However, compared with the MS group, the RM group had shorter hospital stay and taster surgical recovery. At a mean follow-up of 44.8 ± 25.0 months, the freedom from more than moderate MR was 93.9% ± 3.5% in RM group and 94.8% ± 2.9% in MS group at 3 years postoperatively. Log-rank test showed that there was no significant difference in the freedom from recurrent significant MR between the two groups （Х^2= 0.247, P = 0.619）. Multivariate analysis revealed that the presence of mild MR at discharge was the independent risk factor for the recurrent significant MR. Conclusion： Right minithoracotomy can achieve the similar therapeutic effects with MS for the patients who received modified artificial chordae technique for treating MR.展开更多
INTRODUCTION Ear surgeons are increasingly concerned about protecting the chorda tympani nerve while avoiding injury to the facial nerve during cochlear implant surgery.The chorda tympani nerve is the sensory branch o...INTRODUCTION Ear surgeons are increasingly concerned about protecting the chorda tympani nerve while avoiding injury to the facial nerve during cochlear implant surgery.The chorda tympani nerve is the sensory branch of the facial nerve and carries taste information and general sensation （e.g.,pain and temperature） from the anterior two-thirds of the tongue.It supplies efferent vasodilator fibers to the tongue and secretomotor fibers to the salivary glands in the floor of the mouth and parotid gland.展开更多
Mitral valve(MV)tissue engineering is still in its early stage,and one major challenge in MV tissue engineering is to identify appropriate scaffold materials.With the potential of acellular MV scaffolds being demonstr...Mitral valve(MV)tissue engineering is still in its early stage,and one major challenge in MV tissue engineering is to identify appropriate scaffold materials.With the potential of acellular MV scaffolds being demonstrated recently,it is important to have a full understanding of the biomechanics of the native MV components and their acellular scaffolds.In this study,we have successfully characterized the structural and mechanical properties of porcine MV components,including anterior leaflet(AL),posterior leaflet(PL),strut chordae,and basal chordae,before and after decellularization.Quantitative DNA assay showed more than 90%reduction in DNA content,and Griffonia simplicifolia(GS)lectin immunohistochemistry confirmed the complete lack of porcine𝛼-Gal antigen in the acellular MV components.In the acellular AL and PL,the atrialis,spongiosa,and fibrosa trilayered structure,along with its ECM constitutes,i.e.,collagen fibers,elastin fibers,and portion of GAGs,were preserved.Never-theless,the ECM of both AL and PL experienced a certain degree of disruption,exhibiting a less dense,porous ECM morphology.The overall anatomical morphology of the strut and basal chordae were also maintained af-ter decellularization,with longitudinal morphology experiencing minimum disruption,but the cross-sectional morphology exhibiting evenly-distributed porous structure.In the acellular AL and PL,the nonlinear anisotropic biaxial mechanical behavior was overall preserved;however,uniaxial tensile tests showed that the removal of cellular content and the disruption of structural ECM did result in small decreases in maximum tensile modulus,tissue extensibility,failure stress,and failure strain for both MV leaflets and chordae.展开更多
Insomnia affects a large portion of the global population,and the long-term use of conventional hypnotics poses risks such as tolerance and cognitive impairment.As a safer alternative,this study evaluated the hypnotic...Insomnia affects a large portion of the global population,and the long-term use of conventional hypnotics poses risks such as tolerance and cognitive impairment.As a safer alternative,this study evaluated the hypnotic effects and underlying pathways of a standardized Gracilariopsis chorda supplement(SGCS),a red seaweed-derived product developed for functional food use.To investigate these effects,we employed a pentobarbital-induced sleep model and electroencephalogram/electromyogram-based polysomnographic analysis in mice,through which SGCS was found to significantly reduce sleep latency and elevate non-rapid eye movement sleep.Notably,delta activity remained unchanged,suggesting that sleep quality was maintained.Co-administration experiments with receptor-specific antagonists revealed that the hypnotic effects of SGCS were blocked by the adenosine A1 receptor(A1R)antagonist cyclopentyl-1,3-dipropylxanthine,but not by the GABAA receptor antagonist(+)-bicuculline.Subsequent binding and functional assays confirmed SGCS as an A1R agonist with notable affinity(IC_(50)=0.12 mg/mL)and efficacy(EC_(50)=0.0775 mg/mL).Solvent fractionation and total phenolic content(TPC)analysis identified the ethyl acetate fraction as the most potent,with hypnotic activity positively correlating with TPC(R2=0.7436).These findings suggest that SGCS enhances sleep primarily via A1R activation and that polyphenols may be key contributors to its sleep-promoting effect.Altogether,this study highlights the therapeutic potential of red seaweed-derived SGCS as a natural sleep aid and supports its development as a functional food or nutraceutical for managing insomnia and improving sleep quality.展开更多
文摘Objective:To isolate and identify active constituents from Gracilaria chorda extract prepared under subcritical water conditions at 210℃(GCSW210)and evaluate their anti-obesity and anti-diabetic effects in 3T3-L1 adipocytes and high-fat diet(HFD)-induced obese zebrafish larvae.Methods:GCSW210 was fractionated through solvent partitioning,ion-exchange chromatography,and silica gel medium-pressure liquid chromatography,followed by preparative high performance liquid chromatography.At each step,bioactivities were assessed in 3T3-L1 adipocytes by Oil Red O staining and 2-NBDG uptake assays.The most active fractions were further purified,and isolated compounds were tested in HFD-induced obese zebrafish larvae.Results:Liquid chromatography-hyphenated analysis with reference standards identified two major compounds in GCSW210:5-hydroxymethylfurfural and bis(5-formylfurfuryl)ether.Both compounds significantly inhibited lipid accumulation in 3T3-L1 adipocytes and modulated gene expression associated with adipogenesis,glucose metabolism,and inflammation in zebrafish.They also enhanced glucose uptake,reduced circulating glucose levels,and improved insulin sensitivity.Notably,the effects were comparable to those of the crude GCSW210 extract.In silico docking studies confirmed stable interactions of both compounds with key metabolic and inflammatory targets,with bis(5-formylfurfuryl)ether showing stronger binding affinities.Conclusions:These findings suggest that 5-hydroxymethylfurfural and bis(5-formylfurfuryl)ether are key contributors to the therapeutic activity of Gracilaria chorda,highlighting its potential as a functional food ingredient for the prevention or management of metabolic disorders.
文摘BACKGROUND The off-label use of various devices has been reported for the transcatheter closure of perimembranous ventricular septal defects(PmVSD) because of serious complications, such as heart block and tricuspid regurgitation(TR),associated with conventional ventricular septal defect devices. However, whether certain defects such as PmVSD with abnormally attached tricuspid are fit for interventional treatment is still disputable.AIM To explore the feasibility and safety of transcatheter closure of PmVSD with abnormally attached tricuspid chordae tendineae using an improved patent ductus arteriosus(PDA) occluder.METHODS We retrospectively analyzed 20 patients diagnosed with PmVSD with abnormally attached tricuspid chordae tendineae who underwent interventional treatment using an improved PDA occluder at our center from January 2012 to January 2016. Baseline characteristics and procedural and follow-up data were analyzed.RESULTS All 20 patients achieved procedure success. No heart block occurred during the operation. One patient had a transient complete right bundle branch block within48 h post-procedure and reverted to normal rhythm after intravenous injections of dexamethasone for 3 d. For all 20 patients, no residual shunt was observed by transthoracic echocardiography post-procedure. During the average follow-up period of 2.4 years, no severe TR was observed.CONCLUSION Using of the improved PDA occluder for the transcatheter closure of PmVSD with abnormally attached tricuspid chordae tendineae is a safe and promising treatment option. However, long-term follow-up in a large group of patients is still warranted.
文摘Background: Recently, the concept of “Respect rather than resect” has been proposed in an attempt to restore mitral valve function. We investigated the results of mitral valve repair for posterior leaflet disease. Methods: Between April 2008 and July 2017, mitral valve repair was performed in 78 cases at our facility. Among them, 37 cases were analyzed. We divided patients into three groups according to the repair techniques used: artificial chordae technique, which uses the anchoring-technique and measured tube technique (Group A, 23 cases), resection and suture technique (Group R, 10 cases), and artificial chordae together with resection and suture technique (Group AR, 4 cases), and compared their postoperative outcomes. Results: Residual postoperative mitral regurgitation (MR) grade in groups A, R and AR at discharge were 0.3 ± 0.4, 0.8 ± 0.9 and 0.0 ± 0.0 (p = 0.07), respectively. Mitral valve areas (cm2) in groups A, R and AR were 3.2 ± 0.6, 2.9 ± 0.6 and 3.0 ± 0.6 (p = 0.47), respectively. Freedom from severe MR at 5 years postoperatively was seen in 91.7%, 90% and 100% (p = 0.92) in groups A, R and AR, respectively. Conclusions: There was no significant difference in postoperative outcomes, as assessed echocardiographically, between the artificial chordae technique and resection and suture technique. The results of all repair techniques were satisfactory.
文摘BACKGROUND Mitral valvuloplasty using artificial chordae tendineae represents an effective surgical approach for treating mitral regurgitation.Achieving precise measurements of artificial chordae tendineae length(CL)is an important factor in the procedure;however,no objective index currently exists to facilitate this measurement.Therefore,preoperative assessment of CL is critical for surgical planning and support.Four-dimensional x-ray micro-computed tomography(4D-CT)may be useful for accurate CL measurement considering that it allows for dynamic three-dimensional(3D)evaluation compared to that with transthoracic echocardiography,a conventional inspection method.AIM To investigate the behavior and length of mitral chordae tendineae during systole using 4D-CT.METHODS Eleven adults aged>70 years without mitral valve disease were evaluated.A 64-slice CT scanner was used to capture 20 phases in the cardiac cycle in electrocardiographic synchronization.The length of the primary chordae tendineae was measured from early systole to early diastole using the 3D image.The primary chordae tendineae originating from the anterior papillary muscle and attached to the A1-2 region and those from the posterior papillary muscle and attached to the A2-3 region were designated as cA and cP,respectively.The behavior and maximum lengths[cA(ma),cP(max)]were compared,and the correlation with body surface area(BSA)was evaluated.RESULTS In all cases,the mitral anterior leaflet chordae tendineae could be measured.In most cases,the cA and cP chordae tendineae could be measured visually.The mean cA(max)and cP(max)were 20.2 mm±1.95 mm and 23.5 mm±4.06 mm,respectively.cP(max)was significantly longer.The correlation coefficients(r)with BSA were 0.60 and 0.78 for cA(max)and cP(max),respectively.Both cA and cP exhibited constant variation in CL during systole,with a maximum 1.16-fold increase in cA and a 1.23-fold increase in cP from early to mid-systole.For cP,CL reached a plateau at 15%and remained elongated until end-systole,whereas for cA,after peaking at 15%,CL shortened slightly and then moved toward its peak again as end-systole approached.CONCLUSION The study suggests that 4D-CT is a valuable tool for accurate measurement of both the length and behavior of chordae tendineae within the anterior leaflet of the mitral valve.
文摘BACKGROUND As left bundle branch pacing(LBBP)is more like physiological pacing,LBBP has emerged as a novel pacing strategy that uses the native conduction system to improve ventricular synchronization with stable pacing parameters.LBBP has been revealed associated with a significantly reduced risk of new-onset atrial fibrillation and heart failure compared with conventional permanent pacemaker implantation.CASE SUMMARY A 64-year-old man was admitted with a 24-h history of chest distress and shortness of breath,which continued unabated.The patient had no symptoms of chest pain,dizziness,syncope,nausea nor vomiting.There were no abnormalities found in routine examinations after admission.Twelve-lead electrocardiogram presented a result of 2:1 atrioventricular block.Coronary angiography was performed the next day and no abnormality was found.Finally,the patient agreed to received LBBP and signed the informed consent.During the process of withdrawing the Medtronic Model 3830 lead into sheath,we found the lead helix was wrapped around the chordae tendineae of the septal valve of tricuspid.Attempts to rotate the 3830 lead failed to release the lead helix from the chordae tendineae,and ultimately we used radiofrequency ablation to ablate the wrapped chordae tendineae.CONCLUSION Radiofrequency ablation effectively solved this problem without complications.It is an effective and reliable method to resolve lead winding chordae.
文摘Objective To investigate the surgical technique and outcomes of replacement of chordae tendineae in mitral valve repair,and evaluate the value of real-time three-di-mensional transesophageal echocardiography in the perioperative period. Methods Thirty-one patients with mitral valve prolapse underwent mitral valve repair using chordae tendineae replacement concomitant with implantation
基金supported by National Key Research and Development Program 2022YFC2409100Chinese Academy of Medical Sciences(CAMS)Innovation Fund for Medical Sciences[CIFMS,(no.2021-I2M-5-013)]111 Project[The Program of Introducing Talents of Discipline to Universities(no.B16033)].
文摘Surgical repair with artificial chordae replacement has emerged asa standard treatment for mitral regurgitation. Expanded polytetrafluoroethylene (ePTFE) sutures are commonly employed asartificial chordae;however, they have certain limitations, such aspotential long-term rupture and undesired material/tissueresponse. This study introduces a novel approach to artificialchordae design, termed the New Artificial Chordae (NAC), whichincorporates a double-layered structure. The NAC comprises amulti-strand braided core composed of ultra-high molecularweight polyethylene (UHMWPE) fibers as the inner core, and anouter tube made of hydrophobic porous ePTFE. Compared totraditional ePTFE sutures, NAC exhibits increased flexibility,enhanced tensile strength, longer elongation and improved fatigue resistance. Moreover, NAC exhibits a more hydrophobic surface,which contributes to enhanced hemocompatibility. The study also includes in vivo investigations conducted on animal models to evaluate the biocompatibility and functional efficacy of the artificial chordae. These experiments demonstrate the enhanced durability andbiocompatibility of the NAC, characterized by improved mechanical strength, minimal tissue response and reduced thrombus formation.These findings suggest the potential application of NAC as a prosthetic chordae replacement, offering promising prospects to address thelimitations associated with current artificial chordae materials and providing novel ideas and approaches for the development of sustainable and biocompatible regenerative biomaterials.
文摘Artificial chordae replacement with expanded polytetrafluoroethylene （ePTFE; Gore-Tex, W.L.Gore and Associates Inc., Flagstaff, AZ, USA） is an established technique for mitral valve repair with excellent long-term results. There is growing interest in the application of artificial chordae to correct mitral valve regurgitation caused by anterior leaflet prolapse. Application of pre-measured artificial chordae facilitates creation of chordae with appropriate length. The aim of this study was to illustrate the technique for creation of pre-measured artificial chordae.
文摘Background： Right minithoracotomy （RM） has been proven to be a sate and effective approach for mitral valve surgery, but the differences of artificial chordae technique between RM and median sternotomy （MS） were seldom reported. Here, we compared the outcomes of modified artificial chordae technique for mitral regurgitation （MR） through RM or MS approaches. Methods： One hundred and eighteen consecutive adult patients who received mitral valve repair with artificial chordae and annuloplasty for MR through RM （n = 58） or MS （n = 60） from January 2006 to January 2015 were analyzed. Results： All of the selected patients underwent mitral valve repair successfully without any complication during the surgery. There was no significant difference between RM group and MS group in cardiopuhnonary bypass time, aortic cross-clamp time, and early postoperative complications. However, compared with the MS group, the RM group had shorter hospital stay and taster surgical recovery. At a mean follow-up of 44.8 ± 25.0 months, the freedom from more than moderate MR was 93.9% ± 3.5% in RM group and 94.8% ± 2.9% in MS group at 3 years postoperatively. Log-rank test showed that there was no significant difference in the freedom from recurrent significant MR between the two groups （Х^2= 0.247, P = 0.619）. Multivariate analysis revealed that the presence of mild MR at discharge was the independent risk factor for the recurrent significant MR. Conclusion： Right minithoracotomy can achieve the similar therapeutic effects with MS for the patients who received modified artificial chordae technique for treating MR.
文摘INTRODUCTION Ear surgeons are increasingly concerned about protecting the chorda tympani nerve while avoiding injury to the facial nerve during cochlear implant surgery.The chorda tympani nerve is the sensory branch of the facial nerve and carries taste information and general sensation （e.g.,pain and temperature） from the anterior two-thirds of the tongue.It supplies efferent vasodilator fibers to the tongue and secretomotor fibers to the salivary glands in the floor of the mouth and parotid gland.
基金supported in part by NIH R15HL159599,R15HL140503,and AHA GRNT17150041,GRNT959644.
文摘Mitral valve(MV)tissue engineering is still in its early stage,and one major challenge in MV tissue engineering is to identify appropriate scaffold materials.With the potential of acellular MV scaffolds being demonstrated recently,it is important to have a full understanding of the biomechanics of the native MV components and their acellular scaffolds.In this study,we have successfully characterized the structural and mechanical properties of porcine MV components,including anterior leaflet(AL),posterior leaflet(PL),strut chordae,and basal chordae,before and after decellularization.Quantitative DNA assay showed more than 90%reduction in DNA content,and Griffonia simplicifolia(GS)lectin immunohistochemistry confirmed the complete lack of porcine𝛼-Gal antigen in the acellular MV components.In the acellular AL and PL,the atrialis,spongiosa,and fibrosa trilayered structure,along with its ECM constitutes,i.e.,collagen fibers,elastin fibers,and portion of GAGs,were preserved.Never-theless,the ECM of both AL and PL experienced a certain degree of disruption,exhibiting a less dense,porous ECM morphology.The overall anatomical morphology of the strut and basal chordae were also maintained af-ter decellularization,with longitudinal morphology experiencing minimum disruption,but the cross-sectional morphology exhibiting evenly-distributed porous structure.In the acellular AL and PL,the nonlinear anisotropic biaxial mechanical behavior was overall preserved;however,uniaxial tensile tests showed that the removal of cellular content and the disruption of structural ECM did result in small decreases in maximum tensile modulus,tissue extensibility,failure stress,and failure strain for both MV leaflets and chordae.
基金supported by Korea Institute of Marine Science&Technology Promotion(KIMST)funded by the Ministry of Oceans and Fisheries,Korea(RS-2022-KS221637).
文摘Insomnia affects a large portion of the global population,and the long-term use of conventional hypnotics poses risks such as tolerance and cognitive impairment.As a safer alternative,this study evaluated the hypnotic effects and underlying pathways of a standardized Gracilariopsis chorda supplement(SGCS),a red seaweed-derived product developed for functional food use.To investigate these effects,we employed a pentobarbital-induced sleep model and electroencephalogram/electromyogram-based polysomnographic analysis in mice,through which SGCS was found to significantly reduce sleep latency and elevate non-rapid eye movement sleep.Notably,delta activity remained unchanged,suggesting that sleep quality was maintained.Co-administration experiments with receptor-specific antagonists revealed that the hypnotic effects of SGCS were blocked by the adenosine A1 receptor(A1R)antagonist cyclopentyl-1,3-dipropylxanthine,but not by the GABAA receptor antagonist(+)-bicuculline.Subsequent binding and functional assays confirmed SGCS as an A1R agonist with notable affinity(IC_(50)=0.12 mg/mL)and efficacy(EC_(50)=0.0775 mg/mL).Solvent fractionation and total phenolic content(TPC)analysis identified the ethyl acetate fraction as the most potent,with hypnotic activity positively correlating with TPC(R2=0.7436).These findings suggest that SGCS enhances sleep primarily via A1R activation and that polyphenols may be key contributors to its sleep-promoting effect.Altogether,this study highlights the therapeutic potential of red seaweed-derived SGCS as a natural sleep aid and supports its development as a functional food or nutraceutical for managing insomnia and improving sleep quality.
