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1.
Genes Dev ; 30(22): 2527-2537, 2016 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-27920087

RESUMO

The master tumor suppressor p53 activates transcription in response to various cellular stresses in part by facilitating recruitment of the transcription machinery to DNA. Recent studies have documented a direct yet poorly characterized interaction between p53 and RNA polymerase II (Pol II). Therefore, we dissected the human p53/Pol II interaction via single-particle cryo-electron microscopy, structural docking, and biochemical analyses. This study reveals that p53 binds Pol II via the Rpb1 and Rpb2 subunits, bridging the DNA-binding cleft of Pol II proximal to the upstream DNA entry site. In addition, the key DNA-binding surface of p53, frequently disrupted in various cancers, remains exposed within the assembly. Furthermore, the p53/Pol II cocomplex displays a closed conformation as defined by the position of the Pol II clamp domain. Notably, the interaction of p53 and Pol II leads to increased Pol II elongation activity. These findings indicate that p53 may structurally regulate DNA-binding functions of Pol II via the clamp domain, thereby providing insights into p53-regulated Pol II transcription.


Assuntos
Modelos Moleculares , RNA Polimerase II/química , RNA Polimerase II/metabolismo , Proteína Supressora de Tumor p53/química , Proteína Supressora de Tumor p53/metabolismo , Microscopia Crioeletrônica , Exodesoxirribonucleases/metabolismo , Humanos , Ligação Proteica , Domínios Proteicos , Estrutura Quaternária de Proteína , Elongação da Transcrição Genética
2.
J Cell Biochem ; 124(7): 943-960, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37210727

RESUMO

Cardiovascular diseases (CVDs) are associated with vascular smooth muscle cell (VSMC) and endothelial cell (EC) damage. Angiotensin1-7 (Ang1-7) and B-type natriuretic peptide (BNP) are responsible for vasodilation and regulation of blood flow. These protective effects of BNP are primarily mediated by the activation of sGCs/cGMP/cGKI pathway. Conversely, Ang1-7 inhibits Angiotensin II-induced contraction and oxidative stress via Mas receptor activation. Thus, the aim of the study was to determine the effect of co-activation of MasR and particulate guanylate cyclase receptor (pGCA) pathways by synthesized novel peptide (NP) in oxidative stress-induced VSMCs and ECs. MTT and Griess reagent assay kits were used for the standardization of the oxidative stress (H2 O2 ) induced model in VSMCs. The expression of targeted receptors in VSMC was done by RT-PCR and Western blot analysis. Protective effect of NP in VSMC and EC was determined by immunocytochemistry, FACS analysis, and Western blot analysis. Underlying mechanisms of EC-dependent VSMC relaxation were done by determining downstream mRNA gene expression and intracellular calcium imaging of cells. Synthesized NP significantly improved oxidative stress-induced injury in VSMCs. Remarkably, the actions of NP were superior to that of the Ang1-7 and BNP alone. Further, a mechanistic study in VSMC and EC suggested the involvement of upstream mediators of calcium inhibition for the therapeutic effect. NP is reported to possess vascular protective activities and is also involved in the improvement of endothelial damage. Moreover, it is highly effective than that of individual peptides BNP and Ang1-7 and therefore it may represent a promising strategy for CVDs.


Assuntos
Cálcio , Músculo Liso Vascular , Músculo Liso Vascular/metabolismo , Cálcio/metabolismo , Células Endoteliais/metabolismo , Miócitos de Músculo Liso/metabolismo , Estresse Oxidativo , Peptídeo Natriurético Encefálico/metabolismo , Células Cultivadas
3.
Chembiochem ; 24(7): e202200533, 2023 04 03.
Artigo em Inglês | MEDLINE | ID: mdl-36449557

RESUMO

Inhibiting the formation of a tight junction between two malaria parasite proteins, apical membrane antigen 1 and rhoptry neck protein 2, crucial for red blood cell invasion, prevents progression of the disease. In this work, we have used a unique approach to design a chimeric peptide, prepared by fusion of the best features of two peptide inhibitors, that has displayed parasite growth inhibition ex vivo with nanomolar IC50 , which is 100 times better than any of its parent peptides. Furthermore, to gain structural insights, we computationally modelled the hybrid peptide on its receptor.


Assuntos
Plasmodium falciparum , Proteínas de Protozoários , Plasmodium falciparum/metabolismo , Proteínas de Protozoários/metabolismo , Antígenos de Protozoários/química , Antígenos de Protozoários/metabolismo , Proteínas de Membrana/química , Peptídeos/química , Eritrócitos/metabolismo
4.
Pediatr Cardiol ; 2023 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-38041710

RESUMO

The need for right ventricular outflow tract reconstruction is common and growing in congenital heart surgery given expanding indications for the repair of congenital as well as acquired heart disease. Various valved conduit options currently exist including homografts, xenograft pulmonary valved conduits (Contegra™), and porcine valved conduits. The major limitation for all conduits is implant durability, which requires reoperation. Currently, cryopreserved homografts are often used given their superiority shown in long-term data. Significant limitations remain in the cost and availability of the graft, particularly for smaller sizes. Contegra conduits are available in a variety of sizes. Nonetheless, the data regarding long-term durability are less robust and studies comparing durability with homografts have been conflicting. Additionally, there is concern for increased rates of late endocarditis in this conduit. Porcine valved conduits offer a reliable option but are limited by structural valve degeneration associated with all types of bioprosthetic heart valve replacements. New developments in the field of tissue engineering have produced promising bio-restorative valved conduits that may overcome many of the limitations of previous conduit technologies. These remain in the early stages of clinical testing. This review summarizes the clinical data surrounding the conduits used most commonly in clinical practice today and explores emerging technologies that may bring us closer to developing the ideal conduit.

5.
Environ Monit Assess ; 195(8): 958, 2023 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-37453030

RESUMO

This study examines hilly terrain's effect on black carbon (BC) dispersion. The apportionment of distinct sources obtained by a two-component mixing model (Aethalometer: AE-33) using improved radiative transfer equations showed the dominance of traffic-derived black carbon (BCFF) emissions in the study region. The AERMOD was used to model BC emissions from moving traffic as a line source and parking lot as area source using observational and WRF-processed meteorology for the winter (January to March 2020). The model results showed that the BC levels substantially vary with local meteorological conditions, traffic volume, and composition. The hilly terrain obstructs the winds and develops a negative pressure loading to a vacuum on the other side of the hills, which promotes the accumulation of emissions, causing high BC concentrations. The pockets of higher concentration were seen at the locations where steep slopes were associated with low winds (<1 m s-1) and hill fogs. The AERMOD model, after statistical evaluation against the observational datasets, has been applied to study the reduction in BCFF concentrations due to the implementation of Indian emission norms as mitigation measures, i.e., BS-IV (equivalent to Euro 4) and BS-VI (equivalent to Euro 6). It was found that the BCFF concentrations for BS-IV and BS-VI reduced by 35% and 75%, respectively. The model was also used to study the contribution of the different vehicular categories to BC concentration.


Assuntos
Poluentes Atmosféricos , Poluentes Atmosféricos/análise , Monitoramento Ambiental/métodos , Carbono/análise , Estações do Ano , Fuligem/análise , Emissões de Veículos/análise
6.
J Card Surg ; 37(4): 930-936, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35094436

RESUMO

OBJECTIVES: Postoperative hyperglycemia occurs in up to 80% of cardiac surgery patients and is associated with poor outcomes. We sought to determine if case-based diabetes workshops for providers would improve postoperative glycemic control and outcomes in patients undergoing coronary artery bypass grafting  (CABG). METHODS: Healthcare providers taking care of patients in the cardiothoracic step-down unit underwent 30-min weekly case-based diabetes workshops over 6 months. Workshops focused on initiation of insulin treatment, titration of insulin dosing, and transitioning from insulin drips to subcutaneous insulin. Isolated-CABG patients were recorded during 29-month periods before (Jan 2013-June 2015) and after training (Jan 2016-June 2018). Glycemic control and outcomes were compared between groups balanced for preoperative risk factors using inverse probability treatment weights. RESULTS: A total of 938 and 1032 patients were included in pre- and posttraining groups, respectively. Compared to the pretraining period, the posttraining period had a lower median of mean patient day glucose levels (151 vs. 144 mg/dl, p < .001) and percentage of patient days with a glucose level >250 mg/dl (20% vs. 14%, p < .001). The percentage of patient days with mean glucose values in the target range (80-180 mg/dl) increased from 71% to 77% (p < .001). The incidence of hypoglycemic events did not significantly change after training (p = .15). The incidence of sepsis was significantly lower in the posttraining period (1.7% vs. 0.2%, p < .001). CONCLUSIONS: Weekly diabetes workshops for healthcare providers were associated with improved glycemic control and reduced postoperative sepsis among isolated CABG patients.


Assuntos
Glicemia , Diabetes Mellitus , Ponte de Artéria Coronária/efeitos adversos , Diabetes Mellitus/epidemiologia , Humanos , Hipoglicemiantes/uso terapêutico , Insulina/efeitos adversos , Resultado do Tratamento
7.
J Am Chem Soc ; 143(44): 18766-18776, 2021 11 10.
Artigo em Inglês | MEDLINE | ID: mdl-34724378

RESUMO

Protein-folding can go wrong in vivo and in vitro, with significant consequences for the living organism and the pharmaceutical industry, respectively. Here we propose a design principle for small-peptide-based protein-specific folding modifiers. The principle is based on constructing a "xenonucleus", which is a prefolded peptide that mimics the folding nucleus of a protein. Using stopped-flow kinetics, NMR spectroscopy, Förster resonance energy transfer, single-molecule force measurements, and molecular dynamics simulations, we demonstrate that a xenonucleus can make the refolding of ubiquitin faster by 33 ± 5%, while variants of the same peptide have little or no effect. Our approach provides a novel method for constructing specific, genetically encodable folding catalysts for suitable proteins that have a well-defined contiguous folding nucleus.


Assuntos
Ubiquitina/química , Modelos Moleculares , Conformação Proteica , Dobramento de Proteína , Ubiquitina/metabolismo
8.
J Artif Organs ; 24(2): 199-206, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33459913

RESUMO

BACKGROUND: Acute myocardial infarction with refractory cardiogenic shock (AMI-RCS) is associated with poor outcomes. Several percutaneous mechanical circulatory support devices exist; however, limitations exist regarding long-term use. Herein, we describe our experience with the temporary surgical CentriMag VAD. METHODS: We reviewed 74 patients with AMI-RCS who underwent CentriMag VAD insertion as bridge-to-decision device from 2007 to 2020. Patients were divided into groups based on introduction of the "shock team" model: Era 1 (2007-2014, n = 51) and Era 2 (2015-2020, n = 23). RESULTS: Era 2 had higher proportion of patients with INTERMACS Profile I. The use of percutaneous MCS as bridge to VAD and the use of minimally invasive VAD were higher in Era 2. There were fewer postoperative bleeding events in Era 2 (80% vs 61%, p = .07). Thirty-day mortality was 23% and 1-year survival was 55%, which were no differences between eras. Destinations after CentriMag VAD included myocardial recovery (39%), durable LVAD (27%), and transplantation (5%). CONCLUSION: CentriMag VAD device represents a viable bridge-to-decision device with acceptable short- and long-term outcomes for patients with AMI-RCS. Stable outcomes in a progressively sicker population may be related to changes in practice patterns as well as introduction of the "shock team" concept.


Assuntos
Coração Auxiliar , Infarto do Miocárdio/cirurgia , Choque Cardiogênico/cirurgia , Adulto , Feminino , Implante de Prótese de Valva Cardíaca/efeitos adversos , Implante de Prótese de Valva Cardíaca/instrumentação , Implante de Prótese de Valva Cardíaca/métodos , Coração Auxiliar/efeitos adversos , História do Século XXI , Humanos , Japão/epidemiologia , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/complicações , Infarto do Miocárdio/epidemiologia , Intervenção Coronária Percutânea/efeitos adversos , Intervenção Coronária Percutânea/instrumentação , Intervenção Coronária Percutânea/métodos , Estudos Retrospectivos , Choque Cardiogênico/epidemiologia , Fatores de Tempo , Resultado do Tratamento
9.
J Artif Organs ; 23(4): 394-396, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32803543

RESUMO

Extracorporeal membrane oxygenation (ECMO) is becoming a key tool for bridge to heart, lung, or heart-lung transplantation, and ambulatory ECMO support offers many advantages to prepare the patients. We here present a case of successful en bloc heart and lung transplantation after long-term ambulatory support with a minimally invasive central venoarterial ECMO approach as bridge to transplant.


Assuntos
Cardiomiopatias/terapia , Oxigenação por Membrana Extracorpórea , Transplante de Coração-Pulmão , Pneumonia/terapia , Cardiomiopatias/cirurgia , Humanos , Masculino , Pessoa de Meia-Idade , Pneumonia/cirurgia , Resultado do Tratamento
10.
Angew Chem Int Ed Engl ; 59(35): 14796-14801, 2020 08 24.
Artigo em Inglês | MEDLINE | ID: mdl-32333711

RESUMO

We report an operationally simple method to facilitate chemical protein synthesis by fully convergent and one-pot native chemical ligations utilizing the fluorenylmethyloxycarbonyl (Fmoc) moiety as an N-masking group of the N-terminal cysteine of the middle peptide thioester segment(s). The Fmoc group is stable to the harsh oxidative conditions frequently used to generate peptide thioesters from peptide hydrazide or o-aminoanilide. The ready availability of Fmoc-Cys(Trt)-OH, which is routinely used in Fmoc solid-phase peptide synthesis, where the Fmoc group is pre-installed on cysteine residue, minimizes additional steps required for the temporary protection of the N-terminal cysteinyl peptides. The Fmoc group is readily removed after ligation by short exposure (<7 min) to 20 % piperidine at pH 11 in aqueous conditions at room temperature. Subsequent native chemical ligation reactions can be performed in presence of piperidine in the same solution at pH 7.


Assuntos
Cisteína/química , Peptídeos/síntese química , Técnicas de Síntese em Fase Sólida/métodos , Humanos
11.
Am J Otolaryngol ; 39(4): 378-382, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29605236

RESUMO

PURPOSE: Assess the quality of information on obstructive sleep apnea (OSA) presented on YouTube for patients. MATERIALS AND METHODS: "Obstructive sleep apnea" was entered into the YouTube search. Two independent reviewers categorized and analyzed videos utilizing a customized scoring-system along with search position, likes, and views. RESULTS: Forty-eight videos were analyzed. Most were educational (52.1%). Educational and news videos had significantly higher scores, but had no significant differences in search position, likes/day, or views/day. Most videos mentioned positive airway pressure (65%), and nearly half (44%) mentioned mandibular devices in the management of OSA. Few videos discussed surgery (13%) or otolaryngology (15%). CONCLUSION: YouTube is a promising source of information for OSA patients. Educational and news videos are of highest quality. General quality measures like search position, views, and likes are not correlated with formally scored value. Sleep surgery and otolaryngologists are minimally mentioned, representing an opportunity for improvement.


Assuntos
Internet , Educação de Pacientes como Assunto , Apneia Obstrutiva do Sono , Gravação em Vídeo , Confiabilidade dos Dados , Humanos , Apneia Obstrutiva do Sono/diagnóstico , Apneia Obstrutiva do Sono/etiologia , Apneia Obstrutiva do Sono/terapia
12.
Biochim Biophys Acta Mol Basis Dis ; 1870(4): 167110, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38462025

RESUMO

BACKGROUND: The aortic endothelium is crucial in preserving vascular tone through endothelium-derived vasodilators and vasoconstrictors. Dysfunction in the endothelium is an early indicator of cardiovascular diseases. Our study explores the therapeutic potential of a dual-acting peptide (DAP) to co-activate Mas and pGCA receptors and restore the balance between vasodilators and vasoconstrictors on endothelial dysfunction in DOCA-salt-induced hypertensive rats. METHODS: DOCA-salt was administered to male wistar rats to induce hypertension, and various parameters, including blood pressure (BP), water intake and body weight were monitored. DAP, Ang1-7, BNP, and losartan were administered to hypertensive rats for three weeks. Histological analysis and isometric tension studies were carried out to assess endothelial function. In addition to this, we used primary aortic endothelial cells for detailed mechanistic investigations. RESULTS: DOCA-salt administration significantly elevated systolic, diastolic, mean arterial BP, and water intake whereas, downregulated the gene expression of Mas and pGCA receptors. However, DAP co-administration attenuated BP increase, upregulated the gene expression of Mas and pGCA receptors, normalized serum and urinary parameters, and effectively reduced fibrosis, inflammation, and vascular calcification. Notably, DAP outperformed the standard drug, Losartan. Our findings indicate that DAP restores aortic function by balancing the NO and ET1-induced pathways. CONCLUSION: Co-activating Mas and pGCA receptors with DAP mitigates vascular damage and enhances endothelial function, emphasizing its potential to maintain a delicate balance between vasodilatory NO and vasoconstrictor ET1 in endothelial dysfunction.


Assuntos
Acetato de Desoxicorticosterona , Hipertensão , Ratos , Masculino , Animais , Endotelina-1/metabolismo , Endotelina-1/farmacologia , Endotelina-1/uso terapêutico , Losartan/farmacologia , Losartan/uso terapêutico , Óxido Nítrico/metabolismo , Acetato de Desoxicorticosterona/efeitos adversos , Células Endoteliais/metabolismo , Vasodilatadores/efeitos adversos , Endotélio Vascular/metabolismo , Ratos Wistar , Vasoconstritores/efeitos adversos , Cloreto de Sódio na Dieta/efeitos adversos
13.
J Thorac Cardiovasc Surg ; 167(3): 1123-1131.e2, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37385527

RESUMO

OBJECTIVE: Primary aortic insufficiency (AI) is a risk factor for autograft reintervention in adults undergoing the Ross procedure. We sought to examine the influence of preoperative AI on autograft durability in children and adolescents. METHODS: From 1993 to 2020, 125 consecutive patients between ages 1 and 18 underwent a Ross procedure. The autograft was implanted using a full-root technique in 123 (98.4%) and included in a polyethelene terephthalate graft in 2 (1.6%). Patients with aortic stenosis (aortic stenosis group) (n = 85) were retrospectively compared with those with AI or mixed disease (AI group) (n = 40). Median length of follow-up was 8.2 years (interquartile range, 3.3-15.4 years). The primary end point was the incidence of severe AI or autograft reintervention. Secondary end points included changes in autograft dimensions analyzed using mixed-effect models. RESULTS: The incidence of severe AI or autograft reintervention was 39.0% ± 13.0% in the AI group and 8.8% ± 4.4% in the aortic stenosis group at 15 years (P = .02). Annulus z scores increased in both aortic stenosis and AI groups over time (P < .001). However, the annulus dilated at a faster rate in the AI group (absolute difference, 3.8 ± 2.0 vs 2.5 ± 1.7; P = .03). Sinus of Valsalva z scores increased in both groups as well (P < .001), but at similar rates over time (P = .11). CONCLUSIONS: Children and adolescents with AI undergoing the Ross procedure have higher rates of autograft failure. Patients with preoperative AI have more pronounced dilatation at the annulus. Akin to adults, a surgical aortic annulus stabilization technique that modulates growth is needed in children.


Assuntos
Insuficiência da Valva Aórtica , Estenose da Valva Aórtica , Valva Pulmonar , Criança , Adulto , Humanos , Adolescente , Insuficiência da Valva Aórtica/cirurgia , Seguimentos , Estudos Retrospectivos , Autoenxertos , Dilatação , Estenose da Valva Aórtica/cirurgia , Transplante Autólogo , Dilatação Patológica , Valva Pulmonar/transplante , Valva Aórtica/cirurgia
14.
J Thorac Cardiovasc Surg ; 167(2): 535-543.e3, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37330208

RESUMO

OBJECTIVE: Since the heart transplant allocation policy change in 2018, there has been an increase in temporary mechanical circulatory support for Status 2 patients. We sought to examine the temporal pattern of waitlist and posttransplant outcomes for Status 2 patients. METHODS: Adult patients in the United Network for Organ Sharing registry who were listed as Status 2 from January 2019 to June 2022 were included. Temporal trends in waitlist time, waitlist events, and posttransplant outcomes were assessed. Probability of transplant or death after being listed was compared over time. Multivariable regression was performed to identify risk factors for mortality after transplant. RESULTS: A total of 6310 patients were included. From 2019 to 2022, the number of Status 2 patients listed increased from 4.2 to 5.9 per day. Microaxial ventricular assist devices at Status 2 listing increased over time (P < .001). During the study period, median waitlist time (18 days vs 23 days, P < .001) as well as Status 2 days (8 days vs 12 days, P < .001) increased. Waitlist mortality remained stable (5.5%); however, probability of transplant within 90 days of Status 2 listing progressively declined (P < .001). Finally, longer waitlist duration was independently associated with 30-day posttransplant mortality (odds ratio, 1.01; 95% confidence interval, 1.00-1.01, P = .02). CONCLUSIONS: Since the allocation policy change there has been a steady rise in the number of patients listed for Status 2. This has led to increasing waitlist times and lower probability of transplantation for Status 2 patients, which may have negative consequences for posttransplant outcomes.


Assuntos
Insuficiência Cardíaca , Transplante de Coração , Coração Auxiliar , Obtenção de Tecidos e Órgãos , Adulto , Humanos , Listas de Espera , Fatores de Risco , Fatores de Tempo , Estudos Retrospectivos
15.
Ann Thorac Surg ; 117(5): 932-939, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38302051

RESUMO

BACKGROUND: This study aimed to describe the use of perioperative mechanical circulatory support (MCS) and its impact on outcomes in patients with ischemic cardiomyopathy who were undergoing surgical revascularization. METHODS: Patients with an ejection fraction <35% who underwent isolated coronary artery bypass grafting (CABG) from 2015 to 2021 were identified (N = 378). Patients were divided into no MCS, preoperative MCS, and postoperative MCS groups on the basis of timing of MCS initiation, which included intraaortic balloon pump, extracorporeal membrane oxygenation, or Impella device (Abiomed) use. The primary outcome of interest was operative mortality. RESULTS: The median Society of Thoracic Surgeons Predicted Risk of Mortality was 2.4%. Sixty-six percent (n = 246) of patients had a previous myocardial infarction, and 61.8% of these patients were within 21 days of CABG. Twenty-one patients (5.6%) presented in cardiogenic shock. The preoperative MCS cohort consisted of 31 patients (8.2%) who underwent CABG a median of 2 days after MCS initiation. Thirty (7.9%) patients required postoperative MCS. Independent risk factors for requiring postoperative MCS included the preoperative ejection fraction (odds ratio, 0.93; P = .01 and the presence of preoperative MCS (odds ratio, 3.06; P = .02). Overall, operative mortality was 3.4%, and 3-year survival was 87.0%. Operative mortality in patients who did and did not receive preoperative MCS was 7.7% and 2.9% (P = .12) with no difference in long-term survival (P = .80), whereas patients requiring postoperative MCS had significantly increased operative (16.7%) and late mortality (63%; P <.01). CONCLUSIONS: CABG can be performed safely in patients with ischemic cardiomyopathy with selective use of perioperative MCS. Despite advanced disease severity, patients requiring preoperative MCS demonstrate acceptable short- and long-term survival. Patients requiring postoperative MCS have increased postoperative morbidity and mortality.


Assuntos
Coração Auxiliar , Isquemia Miocárdica , Humanos , Masculino , Feminino , Pessoa de Meia-Idade , Isquemia Miocárdica/cirurgia , Isquemia Miocárdica/mortalidade , Estudos Retrospectivos , Idoso , Ponte de Artéria Coronária/métodos , Balão Intra-Aórtico , Cardiomiopatias/cirurgia , Cardiomiopatias/mortalidade , Resultado do Tratamento , Oxigenação por Membrana Extracorpórea/métodos
16.
Artigo em Inglês | MEDLINE | ID: mdl-38266983

RESUMO

OBJECTIVE: Preoperative aortic insufficiency (AI) is associated with inferior autograft durability after the Ross procedure. However, many patients with aortic stenosis (AS) undergo balloon aortic valvuloplasty (BAV) early and present with longstanding AI before Ross. We studied how BAV and subsequent valvular pathology impacts autograft durability. METHODS: Patients undergoing the Ross operation from 1993 to 2020 were identified. Those who underwent BAV before Ross were compared with patients who did not undergo BAV and underwent Ross for predominant AI (AI group) or AS (AS group). Those who underwent previous open surgical aortic valve intervention were excluded. Primary outcome of interest was autograft failure, defined as a composite of autograft reintervention or severe insufficiency. RESULTS: A total of 198 patients were included. Seventy-nine (39.9%) underwent BAV and subsequently underwent the Ross for predominant AI (45.6%) or AS (54.4%). Of patients who did not undergo BAV, 66 (33.3%) presented with predominant AI and 53 (26.8%) with AS. Freedom from autograft failure at 15 years was 90%, 92%, and 62% in BAV, AS, and AI groups, respectively. The AI group was at significantly increased risk of long-term autograft failure (hazard ratio, 5.6; P = .01), whereas the AS and BAV groups had similar, low risk (hazard ratio, 1.1; P = .91). Autograft durability was similar among patients who received BAV and presented with AS or AI before the Ross (P = .84). CONCLUSIONS: BAV before the Ross procedure is common in patients with AS. These patients have excellent long-term autograft durability regardless of preoperative valvular pathology and should strongly be considered for the Ross operation.

17.
Artigo em Inglês | MEDLINE | ID: mdl-38266984

RESUMO

BACKGROUND: Autograft durability and remodeling are thought to be superior in younger pediatric patients after the Ross operation. We sought to delineate the fate of autografts across the pediatric age spectrum in patients with primary aortic stenosis (AS). METHODS: We retrospectively reviewed patients age ≤18 years with primary AS who underwent the Ross operation between 1993 and 2020. Patients were categorized by age. The primary endpoint was autograft dimensional change, and secondary endpoints were severe neo-aortic insufficiency (AI) and autograft reintervention. RESULTS: A total of 119 patients underwent the Ross operation, including 37 (31.1%) in group I (age <18 months), 24 (20.2%) in group II (age 18 months-8 years), and 58 (48.7%) in group III (age 8-18 years). All groups exhibited similar annular growth rates within the first 5 postoperative years, followed by a collective decrease in annulus growth rates from year 5 to year 10. Group III experienced rapid sinus dilation in the first 5 years, followed by stabilization of the sinus z-score from year 5 to year 10, whereas groups I and II demonstrated stable sinus z-scores over 10 years. There were 4 early deaths (3.4%) and 2 late deaths (1.7%) at a median follow-up of 8.1 years (range, 0.01-26.3 years). At 15 years, the incidences of severe neo-AI (0.0 ± 0.0% vs 0.0 ± 0.0% vs 3.9 ± 3.9%; P = .52) and autograft reintervention (8.4 ± 6.0% vs 0.0 ± 0.0% vs 2.4 ± 2.4%; P = .47) were similar in the 3 groups. CONCLUSIONS: Age at the time of Ross operation for primary AS does not influence long-term autograft remodeling or durability. Other physiologic or technical factors are likely greater determinants of autograft fate.

18.
J Thorac Cardiovasc Surg ; 167(4): 1229-1238.e7, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37156363

RESUMO

OBJECTIVE: Studies of reintervention after valve-sparing aortic root replacement (VSRR) are limited by sample size and failure to evaluate all types of reinterventions, including distal aorta and transcatheter interventions. In this report, reintervention after VSRR using a large patient cohort was comprehensively analyzed. METHODS: In a series involving 2 academic aortic centers, 781 consecutive patients from 2005 to 2020 undergoing David V VSRR for aortic aneurysm (91%) or dissection (9%) were included. Median age was 50 years, and 23% had a bicuspid aortic valve (AV). Median follow-up was 7.0 years. Open or transcatheter reintervention on the AV, proximal, or distal thoracic aorta was identified. Cumulative incidence was calculated, and subdistribution hazard models identified factors associated with reintervention. Time-dependent incidence of reintervention was plotted using risk-hazard functions. RESULTS: Sixty-eight reinterventions (57 open, 11 transcatheter) were performed. Reinterventions were divided by indication into degenerative AV (n = 26, including 1 transcatheter aortic valve replacement), endocarditis (n = 11), proximal aorta (n = 8), and distal aorta (n = 23, including 10 thoracic endovascular aortic repairs). Risk of reintervention for endocarditis peaked 1 to 3 years after VSRR, whereas other indications had stable, low rates of occurrence throughout the follow-up period. The cumulative incidence of reintervention was 12.5% whereas the cumulative incidence of AV reintervention was 7.0% at 10 years and was associated with residual postoperative aortic insufficiency. In-hospital mortality after reintervention was 3%. CONCLUSIONS: Reintervention rates after VSRR are relatively low in long-term follow-up and can be performed with acceptable operative risk. The majority of reinterventions are performed for indications other than AV degeneration, with the timing of reintervention varying by the specific clinical indication.


Assuntos
Aneurisma Aórtico , Endocardite , Implante de Prótese de Valva Cardíaca , Humanos , Pessoa de Meia-Idade , Valva Aórtica/diagnóstico por imagem , Valva Aórtica/cirurgia , Estudos Retrospectivos , Aorta/cirurgia , Aneurisma Aórtico/cirurgia , Implante de Prótese de Valva Cardíaca/métodos , Endocardite/cirurgia , Resultado do Tratamento
19.
J Thorac Dis ; 16(1): 26-39, 2024 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-38410607

RESUMO

Background: Systolic anterior motion (SAM) of the mitral valve can result in mitral regurgitation (MR) and adverse outcomes in patients with obstructive hypertrophic cardiomyopathy (HCM). However, the mechanism and characteristics of MR severity mediated by SAM are unresolved. This study aimed to elucidate the anatomic and hemodynamic associations of MR and the impact of septal myectomy on changes in MR severity in patients with HCM. Methods: We retrospectively reviewed patients who underwent septal myectomy with SAM and interpretable imaging between 2017-2022. Significant MR was defined as moderate or more MR. The mitral valve, papillary muscle, and left ventricular geometry were quantitatively evaluated via echocardiography and cardiac computed tomography. Results: Out of 34 patients, two groups were identified: those with preoperative significant MR (n=16) and those without significant MR (n=18). Patients with significant preoperative MR exhibited worse heart failure symptoms at baseline than those without. Following myectomy, these patients showed higher residual left ventricular outflow tract (LVOT) gradients at rest and with provocative measures than those without preoperative MR. Multivariate regression analysis revealed a significant association between the tenting area and MR severity. Additionally, the chordal cutting procedure alleviated the tenting area [2.1 (1.8-2.6) vs. 1.4 (1.2-1.6) cm2] compared to those without it. Conclusions: Our preliminary data suggested that chordal cutting with septal myectomy was associated with an improvement in the tenting area, contributing to MR severity. This procedure may serve as an effective therapy for patients with SAM and significant MR.

20.
Sci Rep ; 13(1): 1719, 2023 01 31.
Artigo em Inglês | MEDLINE | ID: mdl-36720908

RESUMO

One of the challenges faced by current CRISPR/Cas9 editing strategies is the difficulty in rapidly selecting clonal populations of biallelically edited cells. Here we present Surface engiNeered fluorEscence Assisted Kit with Protein Epitope Enhanced Capture (SNEAK PEEC), a platform that combines human genome editing with cell-surface display, which enables the direct identification of biallelically edited clones with minimal screening.


Assuntos
Sistemas CRISPR-Cas , Edição de Genes , Humanos , Sistemas CRISPR-Cas/genética , Membrana Celular , Células Clonais , Epitopos
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