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1.
Ann Biomed Eng ; 2022 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-35428905

RESUMO

Accurate reconstruction of transcatheter aortic valve (TAV) geometries and other stented cardiac devices from computed tomography (CT) images is challenging, mainly associated with blooming artifacts caused by the metallic stents. In addition, bioprosthetic leaflets of TAVs are difficult to segment due to the low signal strengths of the tissues. This paper describes a method that exploits the known device geometry and uses an image registration-based reconstruction method to accurately recover the in vivo stent and leaflet geometries from patient-specific CT images. Error analyses have shown that the geometric error of the stent reconstruction is around 0.1mm, lower than 1/3 of the stent width or most of the CT scan resolutions. Moreover, the method only requires a few human inputs and is robust to input biases. The geometry and the residual stress of the leaflets can be subsequently computed using finite element analysis (FEA) with displacement boundary conditions derived from the registration. Finally, the stress distribution in self-expandable stents can be reasonably estimated by an FEA-based simulation. This method can be used in pre-surgical planning for TAV-in-TAV procedures or for in vivo assessment of surgical outcomes from post-procedural CT scans. It can also be used to reconstruct other medical devices such as coronary stents.

3.
J Biol Chem ; 298(4): 101813, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35278429

RESUMO

High plasma lipid levels have been demonstrated to increase cardiovascular disease risk. Despite advances in treatments to decrease plasma lipids, additional therapeutics are still needed because many people are intolerant or nonresponsive to these therapies. We previously showed that increasing cellular levels of microRNA-30c (miR-30c) using viral vectors or liposomes reduces plasma lipids and atherosclerosis. In this study, we aimed to synthesize potent miR-30c analogs that can be delivered to hepatoma cells without the aid of viral vectors and lipid emulsions. We hypothesized that modification of the passenger strand of miR-30c would increase the stability of miR-30c and augment its delivery to liver cells. Here, we report the successful synthesis of a series of miR-30c analogs by using different chemically modified nucleosides. In these analogs, we left the active sense strand untouched so that its biological activity remained unaltered, and we modified the passenger strand of miR-30c to enhance the stability and uptake of miR-30c by hepatoma cells through phosphorothiorate linkages and the addition of GalNAc. We show that these analogs significantly reduced apolipoprotein B secretion in Huh-7 human hepatoma cells and human primary hepatocytes without affecting apolipoprotein A1 secretion and cellular lipid levels. Our results provide a proof of concept that the passenger strand of miR-30c can be modified to increase its stability and delivery to cells while retaining the potency of the sense strand. We anticipate these miR-30c analogs will be useful in the development of more efficacious analogs for the treatment of hyperlipidemias and cardiovascular diseases.


Assuntos
Apolipoproteínas B , Carcinoma Hepatocelular , Hepatócitos , Neoplasias Hepáticas , Apolipoproteínas B/metabolismo , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/metabolismo , Células Cultivadas , Hepatócitos/efeitos dos fármacos , Humanos , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , MicroRNAs/genética , MicroRNAs/metabolismo , MicroRNAs/farmacologia
5.
Curr Cardiol Rep ; 24(1): 33-41, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-35099762

RESUMO

PURPOSE OF REVIEW: Bicuspid aortic valve (BAV) disease is the most common congenital heart defect worldwide. When severe, symptomatic aortic stenosis ensues, the treatment has increasingly become transcatheter aortic valve replacement (TAVR). The purpose of this review is to identify BAV classification and imaging methods, outline TAVR outcomes in BAV anatomy, and discuss how computational modeling can enhance TAVR treatment in BAV patients. RECENT FINDINGS: TAVR use in BAV patients, when compared to use in tricuspid aortic valves, showed lower device success rate, and there remains no long-term randomized trial data. It has been reported that BAV patients with severe calcification increase the rate of complications. Additionally, the asymmetrical morphology of BAVs often results in asymmetric stent geometries which have implications for increased thrombosis risk and decreased durability. These adverse outcomes are currently very difficult to predict from routine pre-procedural imaging alone. Recently developed patient specific experimental and computational techniques have the potential to assist in filling knowledge gaps in the mechanisms of these complications and provide more information during preclinical planning for better TAVR selection in low surgical risk BAV patients. Efficacy of TAVR for irregular BAV anatomies remains concerning due to the lack of a long-term randomized trial data, their increased rate of short-term complications, and signs that long-term durability could be an issue. More knowledge on identifying which BAV anatomies are at greater risk for these adverse outcomes can potentially improve patient selection for TAVR versus SAVR in low surgical risk BAV patients.


Assuntos
Estenose da Valva Aórtica , Doença da Válvula Aórtica Bicúspide , Doenças das Valvas Cardíacas , Estenose da Valva Mitral , Substituição da Valva Aórtica Transcateter , Valva Aórtica/anormalidades , Valva Aórtica/diagnóstico por imagem , Valva Aórtica/cirurgia , Estenose da Valva Aórtica/etiologia , Estenose da Valva Aórtica/cirurgia , Constrição Patológica , Doenças das Valvas Cardíacas/complicações , Doenças das Valvas Cardíacas/cirurgia , Humanos , Estenose da Valva Mitral/cirurgia , Substituição da Valva Aórtica Transcateter/efeitos adversos , Substituição da Valva Aórtica Transcateter/métodos , Resultado do Tratamento
6.
Interv Cardiol Clin ; 11(1): 81-86, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34838299

RESUMO

Tricuspid valve surgery has high mortality for first-time operations and repeat surgery is fraught with even higher rates. When failed tricuspid surgical prostheses and repairs are present, physicians look toward transcatheter tricuspid valve replacement (TTVR) as a tangible solution. Using balloon-expandable bioprosthetic valves in an off-label fashion, tricuspid valve-in-valve (TViV) procedures can be performed reliably; however, valve-in-ring cases are more nuanced and have higher risks of paravalvular leak and valve malpositioning. TTVR specific issues include THV anchoring, management of preexisting pacing leads, postprocedure thromboembolic prophylaxis, and possible tricuspid reintervention.


Assuntos
Implante de Prótese de Valva Cardíaca , Insuficiência da Valva Tricúspide , Humanos , Reoperação , Resultado do Tratamento , Valva Tricúspide/diagnóstico por imagem , Valva Tricúspide/cirurgia , Insuficiência da Valva Tricúspide/cirurgia
7.
Ann Thorac Surg ; 2021 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-34785247

RESUMO

BACKGROUND: The relationship between institutional volume and operative mortality after surgical aortic valve replacement (SAVR) remains unclear. METHODS: From January 2013 to June 2018, 234 556 patients underwent isolated SAVR (n = 144 177) or SAVR with coronary artery bypass grafting (CABG) (n = 90 379) within the Society of Thoracic Surgeons Adult Cardiac Surgery Database. The association between annualized SAVR volume (group 1 [1-25 SAVRs], group 2 [26-50 SAVRs], group 3 [51-100 SAVRs], and group 4 [>100 SAVRs]) and operative mortality and composite major morbidity or mortality was assessed. Random effects models were used to evaluate whether historical (2013-2015) SAVR volume or risk-adjusted outcomes explained future (2016-2018) risk-adjusted outcomes. RESULTS: The annualized median number of SAVRs per site was 35 (interquartile range, 22-59; isolated aortic valve replacement [AVR], 20; AVR with CABG, 13). Among isolated SAVR cases, the mean operative mortality and composite morbidity or mortality were 1.5% and 9.7%, respectively, at the highest-volume sites (group 4), with significantly higher rates among progressively lower-volume groups (P trend < .001). After adjustment, lower-volume centers had increased odds of operative mortality (group 1 vs group 4 [reference]: adjusted odds ratio [AOR] for SAVR, 2.24 [95% CI, 1.91-2.64]; AOR for SAVR with CABG, 1.96 [95% CI, 1.67-2.30]) and major morbidity or mortality (AOR for SAVR, 1.53 [95% CI, 1.39-1.69]; AOR for SAVR with CABG, 1.46 [95% CI, 1.32-1.61]) compared with the highest-volume institutions. Substantial variation in outcomes was observed across hospitals within each volume category, and prior outcomes explained a greater proportion of hospital operative outcomes than did prior volume. CONCLUSIONS: Operative outcomes after SAVR with or without CABG is inversely associated with institutional procedure volumes; however, prior outcomes are more predictive of future outcomes than is prior volume. Given the excellent outcomes observed at many lower-volume hospitals, procedural outcomes may be preferable to procedural volumes as a quality metric.

8.
J Oral Biol Craniofac Res ; 11(4): 581-595, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34540578

RESUMO

INTRODUCTION: TMJ ankylosis (TMJa) management by arthroplasty alone fails to address the deformity and the compromised airway. Distraction osteogenesis (DO) can offer a pragmatic solution to TMJa. The aim of the study was to generate evidence towards the role of DO in TMJa, evaluate its efficiency and develop an algorithm for use of DO in TMJa. MATERIAL AND METHODS: The research question was formulated using the PICOS statement for reporting guidelines in systematic reviews, where the efficiency of DO was evaluated in terms of mouth opening, correction of facial deformity and asymmetry, airway correction, and its long term effects. RESULTS: 1130 articles reported DO as a treatment modality for TMJ ankylosis, of which 32 prospective studies, 16 retrospective and 2 RCTs were included in the study. DO was used for mandibular distraction in 45 studies and for simultaneous maxillamandibular distraction in only five studies. An algorithm for use of DO in TMJa was developed. CONCLUSION: Although DO has proven its application in TMJ ankylosis cases, its best use is for correction of obstructive sleep apnoea. Relapse causing loss of posterior ramal height is a concern after transport DO. Prearthroplastic DO appears to best correct mandibular deformity. A maxillomandibular deformity requires simultaneous maxillomandibular distraction. However, a metanalysis is still awaited for effectiveness of DO in TMJ ankylosis.

9.
J Biomol Struct Dyn ; : 1-11, 2021 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-34427179

RESUMO

Corona Virus Disease (COVID-19) caused by Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) is a pandemic that has claimed so far over half a million human life across the globe. Researchers all over the world are exploring various molecules including phytochemicals to get a potential anti-COVID-19 drug. Certain phytochemicals present in some spices are claimed to possess antiviral, anti-bacterial, and anti-fungal properties. Hence, an in-silico study was done by selecting eighteen well reported antiviral phytochemicals from some spices commonly used in Indian kitchen viz. Curcuma longa (Turmeric), Nigella sativa (Black cumin), Piper nigrum (Black pepper), Trachyspermum ammi (Carom) and Zingiber officinale (Ginger) to find out whether they can prevent SARS-CoV-2 infection. Firstly, we predicted the structure of TMPRSS2 (transmembrane protease serine 2), a host protein that truncates spike protein of SARS-CoV-2 thereby facilitating its endocytosis, and then docked against its catalytic domain the selected phytochemicals and camostat (a well-known synthetic inhibitor of TMPRSS2). Thereafter, stability of seven best docked phytochemicals and camostat were scrutinized by Molecular Dynamic Simulation (MDS). MDS analysis indicated bisdemethoxycurcumin (BDMC), carvacrol and thymol as better inhibitors than the camostat due to their stable binding with TMPRSS2 in its oxyanion hole and inducing subtle modification in the spatial arrangement of the catalytic triad residues. Among these three phytochemicals, carvacrol appeared to be the best inhibitor, followed by BDMC, whereas thymol was least effective.Communicated by Ramaswamy H. Sarma.

12.
JACC Cardiovasc Interv ; 14(5): 541-550, 2021 03 08.
Artigo em Inglês | MEDLINE | ID: mdl-33663781

RESUMO

OBJECTIVES: The purpose of this study was to evaluate tip-to-base intentional laceration of the anterior mitral leaflet to prevent left ventricular outflow tract obstruction (LAMPOON) in patients undergoing transcatheter mitral valve replacement (TMVR) in annuloplasty rings or surgical mitral valves. BACKGROUND: LAMPOON is an effective adjunct to TMVR that prevents left ventricular outflow tract obstruction (LVOTO). Laceration is typically performed from the base to the tip of the anterior mitral leaflet. A modified laceration technique from leaflet tip to base may be effective in patients with a prosthesis that protects the aortomitral curtain. METHODS: This is a multicenter, 21-patient, consecutive retrospective observational cohort. Patients underwent tip-to-base LAMPOON to prevent LVOTO and leaflet overhang, or therapeutically to lacerate a long anterior mitral leaflet risking or causing LVOTO. Outcomes were compared with findings from patients in the LAMPOON investigational device exemption trial with a prior mitral annuloplasty. RESULTS: Twenty-one patients with a annuloplasty or valve prosthesis-protected mitral annulus underwent tip-to-base LAMPOON (19 preventive, 2 rescue). Leaflet laceration was successful in all and successfully prevented or treated LVOTO in all patients. No patients had significant LVOTO upon discharge. There were 2 cases of unintentional aortic valve injury (1 patient underwent emergency transcatheter aortic valve replacement and 1 patient underwent urgent surgical aortic valve replacement). In both cases, the patients had a supra-annular ring annuloplasty, and the retrograde aortic guiding catheter failed to insulate the guidewire lacerating surface from the aortic root. All patients survived to 30 days. Compared with classic retrograde LAMPOON, there was a trend toward shorter procedure time. CONCLUSIONS: Tip-to-base laceration is a simple, effective, and safe LAMPOON variant applicable to patients with an appropriately positioned mitral annular ring or bioprosthetic valve. Operators should take care to insulate the lacerating surface from adjacent structures.


Assuntos
Implante de Prótese de Valva Cardíaca , Próteses Valvulares Cardíacas , Insuficiência da Valva Mitral , Obstrução do Fluxo Ventricular Externo , Cateterismo Cardíaco/efeitos adversos , Implante de Prótese de Valva Cardíaca/efeitos adversos , Humanos , Valva Mitral/diagnóstico por imagem , Valva Mitral/cirurgia , Insuficiência da Valva Mitral/diagnóstico por imagem , Insuficiência da Valva Mitral/cirurgia , Estudos Retrospectivos , Resultado do Tratamento
13.
JACC Cardiovasc Imaging ; 14(1): 112-127, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33413881

RESUMO

There has been rapid progress in transcatheter therapies for mitral regurgitation. These developments have elevated the need for the imager to have a core understanding of the functional mitral valve anatomy. Pre- and intraoperative echocardiography for surgical mitral valve repair for mitral regurgitation has defined contemporary interventional imaging in many ways. The central tenets of these principles apply to interventional imaging of transcatheter mitral valve interventions. However, the heightened emphasis on procedural planning and procedural imaging is one of the new challenges posed by transcatheter interventions. This need for accurate and reliable information has required the imager to be agnostic to the imaging modality. Cardiac computed tomography has become critical in procedural planning in this new paradigm. The expanded use of pre-procedural cardiac magnetic resonance to quantify mitral regurgitation and characterize the left ventricle is another illustration of this newer approach. Other illustrations of the new world of interventional imaging include the expanded use of 3-dimensional (3D) transesophageal echocardiography and real-time fusion of echocardiography and fluoroscopy images. Imaging data are also the basis for computational modeling, 3D printing, and artificial intelligence. These technologies are being increasingly explored to improve therapy selection and prediction of procedural outcomes. This review provides an update of the essentials in present interventional imaging for surgical and transcatheter interventions for mitral regurgitation.


Assuntos
Implante de Prótese de Valva Cardíaca , Insuficiência da Valva Mitral , Valva Mitral , Inteligência Artificial , Cateterismo Cardíaco , Humanos , Valva Mitral/cirurgia , Insuficiência da Valva Mitral/cirurgia , Valor Preditivo dos Testes
14.
Ann Thorac Surg ; 111(2): 390-397, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-32798455

RESUMO

BACKGROUND: The presence of mitral annular calcification (MAC) in patients with mitral valve (MV) stenosis or regurgitation is a difficult scenario for surgeons and the heart team. Patients with MAC most often have a significant number of comorbidities that exclude them as surgical candidates. This review highlights the various contemporary techniques available to manage MAC during treatment of the MV. METHODS: This study is a focused review of the anatomy, pathology, and management of MAC. The review describes the surgical and transcatheter techniques with outcomes, where available. RESULTS: The incidence of MAC is between 5% and 42% in patients with severe MV disease. The pathophysiology underlying MAC is not yet clear, but it most likely is related to processes of inflammation and atherosclerosis. Surgical techniques can be grouped into those in which the MAC is completely resected en bloc and those in which the MAC is incompletely resected or left in situ. Transcatheter therapies are feasible in some patients, but they have been limited by the anatomic constraints of MAC; most importantly left ventricular outflow tract obstruction and paravalvular regurgitation. CONCLUSIONS: Surgeons as part of the heart team now have a range of techniques to manage MAC in those patients with severe MV disease. Transcatheter therapies may increase the options for patients whose surgical risk is too high.


Assuntos
Calcinose/cirurgia , Cateterismo Cardíaco/métodos , Doenças das Valvas Cardíacas/cirurgia , Implante de Prótese de Valva Cardíaca/métodos , Valva Mitral/cirurgia , Humanos , Resultado do Tratamento
18.
Anal Bioanal Chem ; 412(15): 3753-3763, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32300842

RESUMO

Here, a fast and eco-friendly one-pot hydrothermal technique is utilized for the synthesis of nitrogen/sulfur-co-doped fluorescent carbon quantum dots (NS-CQDs) from a simple precursor of citric acid (CA) and thiosemicarbazide (TSC). The obtained NS-CQDs exhibited strong blue emission under UV light, with fluorescence quantum yield (QY) of ~37.8%. The Commission internationale de l'eclairage (CIE) coordinates originated at (0.15, 0.07), which confirmed the blue fluorescence of the synthesized NS-CQDs. Interestingly, the prepared NS-CQDs were successfully used as a selective nanoprobe for the monitoring of environmentally hazardous explosive picric acid (PA) in different nitro- and non-nitro-aromatic derivatives of PA. The mechanism of the NS-CQDs was also explored, and was posited to occur via the fluorescence resonance electron transfer (FRET) process and non-fluorescent complex formation. Importantly, this system possesses excellent biocompatibility and low cytotoxicity in HeLa cervical cancer cells; hence, it can potentially be used for PA detection in analytical, environmental, and pathological applications. Furthermore, the practical applicability of the proposed sensing system to pond water demonstrated the feasibility of our system along with good recovery. Graphical abstract.


Assuntos
Carbono/química , Nitrogênio/química , Picratos/análise , Pontos Quânticos/química , Materiais Biocompatíveis/química , Corantes Fluorescentes/química , Células HeLa , Humanos , Espectrometria de Fluorescência/métodos , Água/análise
19.
Luminescence ; 35(6): 913-923, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32198843

RESUMO

In this study, we prepared carbon dots (CDs) from wheat bran via hydrothermal treatment at 180°C for 3 h. The prepared CDs showed blue-green fluorescence under UV light. The fluorescence emission study of the CDs revealed that they showed maximum fluorescence emission at 500 nm. The prepared CDs showed a high quantum yield of 33.23%. Solvent-dependent fluorescence emission analysis of the CDs was performed to study the variation in fluorescence emission characteristics with solvent polarity. The prepared CDs were conjugated with amoxicillin (AMX) to explore its potential for use as a drug delivery agent for AMX. The drug release profile of the CD-AMX conjugates was analyzed at different pH (5.0, 6.8 and 7.2) to study drug release kinetics. CD-AMX conjugates showed notable bacterial inhibition against Gram-positive (S. aureus) and Gram-negative (E. coli) strains with minimal cytotoxic effects, indicating its potential as a promising antibacterial drug delivery system.


Assuntos
Carbono , Pontos Quânticos , Fibras na Dieta , Sistemas de Liberação de Medicamentos , Escherichia coli , Corantes Fluorescentes , Staphylococcus aureus
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