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1.
Proc Natl Acad Sci U S A ; 120(1): e2219054120, 2023 01 03.
Artigo em Inglês | MEDLINE | ID: mdl-36574676

RESUMO

Bioprosthetic heart valves (BHV), made from glutaraldehyde-fixed xenografts, are widely used for surgical and transcatheter valve interventions but suffer from limited durability due to structural valve degeneration (SVD). We focused on metabolic syndrome (MetS), a risk factor for SVD and a highly prevalent phenotype in patients affected by valvular heart disease with a well-recognized cluster of comorbidities. Multicenter patient data (N = 251) revealed that patients with MetS were at significantly higher risk of accelerated SVD and required BHV replacement sooner. Using a next-generation proteomics approach, we identified significantly differential proteomes from leaflets of explanted BHV from MetS and non-MetS patients (N = 24). Given the significance of protein infiltration in MetS-induced SVD, we then demonstrated the protective effects of polyoxazoline modification of BHV leaflets to mitigate MetS-induced BHV biomaterial degeneration (calcification, tissue cross-linking, and microstructural changes) in an ex vivo serum model and an in vivo with MetS rat subcutaneous implants.


Assuntos
Bioprótese , Próteses Valvulares Cardíacas , Síndrome Metabólica , Humanos , Animais , Ratos , Síndrome Metabólica/complicações , Valvas Cardíacas , Fatores de Risco , Valva Aórtica/cirurgia
2.
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.

3.
Pediatr Surg Int ; 38(3): 399-407, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34837497

RESUMO

PURPOSE: The significance and management of pediatric pneumatosis intestinalis (PI) remains poorly defined. We sought to add clarity in children beyond the neonatal period. METHODS: Pediatric patients 3 months-18 years admitted to a quaternary children's hospital with a diagnosis of PI were included in this retrospective study. Pathologic PI was defined as irreversible, transmural intestinal ischemia. RESULTS: 167 children were identified with PI. Of these children, 155 (92.8%) had benign PI and 12 (7.2%) developed pathologic PI. The most common underlying diagnosis for pathologic PI was global developmental delay (75%), although we identified a spectrum of underlying diagnoses at risk for PI. Physical exam notable for abdominal distension (p = 0.023) or guarding (p = 0.028), and imaging with portal venous gas (p < 0.001) or bowel distension (p = 0.001) were significantly associated with pathologic PI. Only 6.6% of all children underwent an operation. For those undergoing non-surgical management of benign PI, 75% of children received antibiotics and average duration of bowel rest was 6.8 days. CONCLUSIONS: PI in children is primarily a benign phenomenon and often does not warrant surgical intervention. Bowel rest and antibiotics are therapeutic strategies frequently used in the treatment of this finding.


Assuntos
Pneumatose Cistoide Intestinal , Criança , Humanos , Recém-Nascido , Intestinos , Pneumatose Cistoide Intestinal/diagnóstico por imagem , Pneumatose Cistoide Intestinal/terapia , Veia Porta , Estudos Retrospectivos
4.
Opt Lett ; 45(9): 2576-2579, 2020 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-32356820

RESUMO

For the first time, we report on the fabrication of a bend-insensitive single-mode bismuth (Bi)-doped $ {{\rm P}_2}{{\rm O}_5} {-} {{\rm SiO}_2} $P2O5-SiO2 fiber having a depressed cladding design and study its gain characteristics at a spectral region of 1.3-1.4 µm. It was shown that the obtained Bi-doped fiber can efficiently operate in the spectral band even at a bend radius of 1.5 cm. In addition, it was shown that this type of fiber has a smaller mode-field diameter in comparison with a step-index single-mode Bi-doped $ {{\rm P}_2}{{\rm O}_5} {-} {{\rm SiO}_2} $P2O5-SiO2 fiber with $ \Delta {n} \approx 0.006 $Δn≈0.006 that resulted in a decrease of saturation power and, as a consequence, in a reduction of the total pump power required to a high-level-gain operation. The laser and gain experiments show the possibility of the construction of a compact high-performance optical amplifier for O-band based on the depressed-cladding Bi-doped fiber.

5.
JMIR Biomed Eng ; 9: e48497, 2024 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-38875691

RESUMO

BACKGROUND: Venovenous extracorporeal membrane oxygenation (VV-ECMO) is a therapy for patients with refractory respiratory failure. The decision to decannulate someone from extracorporeal membrane oxygenation (ECMO) often involves weaning trials and clinical intuition. To date, there are limited prognostication metrics to guide clinical decision-making to determine which patients will be successfully weaned and decannulated. OBJECTIVE: This study aims to assist clinicians with the decision to decannulate a patient from ECMO, using Continuous Evaluation of VV-ECMO Outcomes (CEVVO), a deep learning-based model for predicting success of decannulation in patients supported on VV-ECMO. The running metric may be applied daily to categorize patients into high-risk and low-risk groups. Using these data, providers may consider initiating a weaning trial based on their expertise and CEVVO. METHODS: Data were collected from 118 patients supported with VV-ECMO at the Columbia University Irving Medical Center. Using a long short-term memory-based network, CEVVO is the first model capable of integrating discrete clinical information with continuous data collected from an ECMO device. A total of 12 sets of 5-fold cross validations were conducted to assess the performance, which was measured using the area under the receiver operating characteristic curve (AUROC) and average precision (AP). To translate the predicted values into a clinically useful metric, the model results were calibrated and stratified into risk groups, ranging from 0 (high risk) to 3 (low risk). To further investigate the performance edge of CEVVO, 2 synthetic data sets were generated using Gaussian process regression. The first data set preserved the long-term dependency of the patient data set, whereas the second did not. RESULTS: CEVVO demonstrated consistently superior classification performance compared with contemporary models (P<.001 and P=.04 compared with the next highest AUROC and AP). Although the model's patient-by-patient predictive power may be too low to be integrated into a clinical setting (AUROC 95% CI 0.6822-0.7055; AP 95% CI 0.8515-0.8682), the patient risk classification system displayed greater potential. When measured at 72 hours, the high-risk group had a successful decannulation rate of 58% (7/12), whereas the low-risk group had a successful decannulation rate of 92% (11/12; P=.04). When measured at 96 hours, the high- and low-risk groups had a successful decannulation rate of 54% (6/11) and 100% (9/9), respectively (P=.01). We hypothesized that the improved performance of CEVVO was owing to its ability to efficiently capture transient temporal patterns. Indeed, CEVVO exhibited improved performance on synthetic data with inherent temporal dependencies (P<.001) compared with logistic regression and a dense neural network. CONCLUSIONS: The ability to interpret and integrate large data sets is paramount for creating accurate models capable of assisting clinicians in risk stratifying patients supported on VV-ECMO. Our framework may guide future incorporation of CEVVO into more comprehensive intensive care monitoring systems.

6.
Surg Obes Relat Dis ; 2024 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-39152058

RESUMO

BACKGROUND: While the lasting effect of the COVID-19 pandemic continues to unfold, the impact on adolescents undergoing bariatric surgery remains unseen. OBJECTIVE: We examined the impact of the pandemic on adolescents undergoing metabolic bariatric surgery. SETTING: Academic hospital, New York, NY. METHODS: A single-institution review of prospectively collected data evaluated adolescents who underwent laparoscopic sleeve gastrectomy between 2010 and 2023, forming two cohorts: pre-COVID (before March 1, 2019) and COVID (after March 1, 2020). Absolute and percent weight loss and body mass index (BMI) change at 6 and 12 months postsurgery were compared between cohorts. Multivariable linear regression models were constructed to estimate the association between weight loss, adjusting for age, gender, ethnicity, and BMI. RESULTS: A total of 358 patients were included: 245 in the pre-COVID cohort and 113 in the COVID cohort. There were no significant differences in baseline characteristics. There were no significant differences between cohorts at 6 months in weight loss (21.6 kg vs. 22.5 kg, P = .43), percent weight loss (18% vs. 18%, P = .63), and BMI change (8.0 vs. 8.4, P = .39) which was maintained at 12 months. In multivariate models, after adjusting for age, gender, ethnicity, and baseline BMI, undergoing surgery during the pandemic was not associated with a difference in weight loss or BMI change at 6 and 12 months postoperatively. CONCLUSION: Despite the severe societal impact of the COVID-19 pandemic, laparoscopic sleeve gastrectomy remained a durable intervention for adolescent obesity, with no observed differences in weight loss in patients undergoing surgery during the pandemic compared to prepandemic.

7.
Genes (Basel) ; 14(7)2023 07 19.
Artigo em Inglês | MEDLINE | ID: mdl-37510376

RESUMO

In recent years, the number of mole species with species status confirmed by genetic methods has been continuously increasing. Unfortunately, cytogenetic data are not yet available for all species. Here, for the first time, a GTG-banded karyotype of the small-toothed mole from Vietnam, Euroscaptor parvidens, a representative of the Eastern clade of the genus Euroscaptor, has been described. Through comparative analysis of available Euroscaptor (Euroscaptor parvidens, Euroscaptor klossi, and Euroscaptor malayana) and Oreoscaptor (Oreoscaptor mizura) karyotypes, we found cytogenetic signatures for each of the studied species. Zoo-FISH with sorted chromosomes of the Siberian mole (Talpa altaica) on chromosome sets of the small-toothed mole (E. parvidens), the small Japanese mole (Mogera imaizumii) from the closely related genus, and the Japanese shrew mole (Urotrichus talpoides) from the tribe Urotrichini made it possible to identify syntenic regions between these species. We propose a possible ancestral karyotype of the tribe and, based on it, traced the features of chromosomal rearrangements accompanying the divergence of moles. The low rates of chromosomal evolution within the species of the genus Talpa-T. altaica and T. europaea-and the high rates of karyotypic reshuffling within the Asian genera of the tribe were confirmed. The karyotype of the Japanese mountain mole O. mizura seems to be the most conserved among the Asian moles. The most frequently occurring types of chromosomal rearrangements in moles are the pericentric inversions and amplification of heterochromatin. The pericentric inversions on four pairs of autosomes are shared between the closely related genera Euroscaptor, Oreoscaptor, and Mogera, while many more apomorphic rearrangements have occurred in each lineage additionally. The highest rate of chromosomal changes, with five rearrangements occurring over approximately 7 million years, was recorded in the lineage of the small-toothed mole.


Assuntos
Toupeiras , Animais , Toupeiras/genética , Cariotipagem , Citogenética , Cariótipo , Musaranhos/genética
8.
Cardiovasc Res ; 119(1): 302-315, 2023 03 17.
Artigo em Inglês | MEDLINE | ID: mdl-35020813

RESUMO

AIMS: Bioprosthetic heart valves (BHVs), made from glutaraldehyde-fixed heterograft materials, are subject to more rapid structural valve degeneration (SVD) in paediatric and young adult patients. Differences in blood biochemistries and propensity for disease accelerate SVD in these patients, which results in multiple re-operations with compounding risks. The goal of this study is to investigate the mechanisms of BHV biomaterial degeneration and present models for studying SVD in young patients and juvenile animal models. METHODS AND RESULTS: We studied SVD in clinical BHV explants from paediatric and young adult patients, juvenile sheep implantation model, rat subcutaneous implants, and an ex vivo serum incubation model. BHV biomaterials were analysed for calcification, collagen microstructure (alignment and crimp), and crosslinking density. Serum markers of calcification and tissue crosslinking were compared between young and adult subjects. We demonstrated that immature subjects were more susceptible to calcification, microstructural changes, and advanced glycation end products formation. In vivo and ex vivo studies comparing immature and mature subjects mirrored SVD in clinical observations. The interaction between host serum and BHV biomaterials leads to significant structural and biochemical changes which impact their functions. CONCLUSIONS: There is an increased risk for accelerated SVD in younger subjects, both experimental animals and patients. Increased calcification, altered collagen microstructure with loss of alignment and increased crimp periods, and increased crosslinking are three main characteristics in BHV explants from young subjects leading to SVD. Together, our studies establish a basis for assessing the increased susceptibility of BHV biomaterials to accelerated SVD in young patients.


Assuntos
Bioprótese , Calcinose , Próteses Valvulares Cardíacas , Animais , Ratos , Ovinos , Valvas Cardíacas , Materiais Biocompatíveis , Colágeno
9.
ASAIO J ; 68(12): e224-e229, 2022 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-36368023

RESUMO

Revised guidelines clarify indications for extracorporeal membrane oxygenation (ECMO) support in Coronavirus disease 2019 (COVID-19) patients with acute respiratory distress syndrome (ARDS). Limited data exist to compare clinical outcomes of COVID-19 ARDS patients to non-COVID-19-related ARDS patients when supported with ECMO. An observational propensity-matched study was performed to compare clinical and ECMO-related complications between COVID-19-related ARDS patients (COVID) and non-COVID-19-related ARDS (Control). COVID- patients cannulated from March 1st, 2020, through June 1st, 2021, were included and matched to patients from the historical cohort at our center from 2012 to 2020 based on age, body mass index (BMI), acute physiology and chronic health evaluation (APACHE) II score, and duration ECMO run. The primary outcome was complications during ECMO therapy. A total of 56 patients were propensity matched 1:1 with a mean age of 40.9 years, BMI 32.1 kg/m2, APACHE II score of 26.6, and duration of ECMO support of 22.6 days. In total 18 COVID-19 patients were observed to have more major bleeding complications (18 vs. 9, p = 0.03). Although not statistically significant, they also had more strokes (6 vs. 3) and required more chest tubes (13 vs. 8). Inpatient mortality was not different. ECMO support in COVID-19 patients is associated with more major bleeding complications, strokes, and chest tube placements. The use of ECMO in patients with COVID-19-related ARDS appears to be associated with an increased risk of complications.


Assuntos
COVID-19 , Oxigenação por Membrana Extracorpórea , Síndrome do Desconforto Respiratório , Humanos , Adulto , Oxigenação por Membrana Extracorpórea/efeitos adversos , COVID-19/complicações , COVID-19/terapia , Pontuação de Propensão , Síndrome do Desconforto Respiratório/etiologia , Síndrome do Desconforto Respiratório/terapia , Hemorragia , Estudos Retrospectivos
10.
J Pediatr Surg ; 56(11): 2045-2051, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34034882

RESUMO

BACKGROUND/PURPOSE: We sought to analyze the use of angioembolization (AE) after pediatric splenic injuries at adult and pediatric trauma centers (ATCs/PTCs). METHODS: The National Trauma Data Bank (2010-2015) was queried for patients (<18 years) who experienced blunt splenic trauma. Multivariate logistic regression was used to determine the association of AE with splenectomy. Propensity score matching was used to explore the relationship between trauma center designation and AE utilization. RESULTS: 14,027 encounters met inclusion criteria. 514 (3.7%) patients underwent AE. When compared to PTCs, patients were older, had a higher ISS, and more often presented in shock at ATCs (p<0.001 for all). Regression models demonstrated no difference in mortality between cohorts. Odds of splenectomy were lower for patients undergoing AE (OR 0.16 [CI: 0.08-0.31]), however this effect was mostly driven by utilization at ATCs. Using a 1:1 propensity score matching model, patients treated at ATCs were 4 times more likely to undergo AE and 7 times more likely to require a splenectomy compared to PTCs (p<0.001). Over 6 years, PTCs performed only 27 splenectomies and 23 AEs (1.1% and 0.9%, respectively). CONCLUSIONS: AE was associated with improved splenic salvage at ATCs in select patients but appeared overutilized when compared to outcomes at PTCs. PTCs accomplished a higher splenic salvage rate with a lower AE utilization. LEVEL OF EVIDENCE: III - Retrospective cohort study.


Assuntos
Traumatismos Abdominais , Embolização Terapêutica , Traumatismo Múltiplo , Ferimentos não Penetrantes , Traumatismos Abdominais/terapia , Adulto , Criança , Humanos , Escala de Gravidade do Ferimento , Traumatismo Múltiplo/terapia , Estudos Retrospectivos , Baço/lesões , Esplenectomia , Centros de Traumatologia , Ferimentos não Penetrantes/complicações , Ferimentos não Penetrantes/terapia
11.
J Pediatr Surg ; 55(1): 33-38, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31677822

RESUMO

BACKGROUND: Congenital diaphragmatic hernia (CDH) occurs in 1 out of 2500-3000 live births. Right-sided CDHs (R-CDHs) comprise 25% of all CDH cases, and data are conflicting on outcomes of these patients. The aim of our study was to compare outcomes in patients with right versus left CDH (L-CDH). METHODS: We analyzed a multicenter prospectively enrolled database to compare baseline characteristics and outcomes of neonates enrolled from January 2005 to January 2019 with R-CDH vs. L-CDH. RESULTS: A total of 588, 495 L-CDH, and 93 R-CDH patients with CDH were analyzed. L-CDHs were more frequently diagnosed prenatally (p=0.011). Lung-to-head ratio was similar in both cohorts. R-CDHs had a lower frequency of primary repair (p=0.022) and a higher frequency of need for oxygen at discharge (p=0.013). However, in a multivariate analysis, need for oxygen at discharge was no longer significantly different. There were no differences in long-term neurodevelopmental outcomes assessed at two year follow up. There was no difference in mortality, need for ECMO, pulmonary hypertension, or hernia recurrence. CONCLUSION: In this large series comparing R to L-CDH patients, we found no significant difference in mortality, use of ECMO, or pulmonary complications. Our study supports prior studies that R-CDHs are relatively larger and more often require a patch or muscle flap for repair. TYPE OF STUDY: Prognosis study LEVEL OF EVIDENCE: Level II.


Assuntos
Hérnias Diafragmáticas Congênitas , Oxigenação por Membrana Extracorpórea , Hérnias Diafragmáticas Congênitas/complicações , Hérnias Diafragmáticas Congênitas/epidemiologia , Hérnias Diafragmáticas Congênitas/mortalidade , Hérnias Diafragmáticas Congênitas/terapia , Humanos , Hipertensão Pulmonar , Recém-Nascido , Estudos Retrospectivos
12.
Opt Express ; 17(16): 13487-92, 2009 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-19654756

RESUMO

IR luminescence and optical gain in a Pb-doped fiber have been observed for the first time. Absorption, luminescence and pump on/pump off optical gain spectra, as well as luminescence decay time, have been measured in these fibers. Comparison of optical active center characteristics in Pb-doped and Bi-doped fibers of the same composition indicates an essential difference of optical active centers in these two types of fibers.


Assuntos
Amplificadores Eletrônicos , Tecnologia de Fibra Óptica/instrumentação , Chumbo/química , Medições Luminescentes/instrumentação , Dispositivos Ópticos , Dióxido de Silício/química , Simulação por Computador , Desenho Assistido por Computador , Desenho de Equipamento , Análise de Falha de Equipamento , Luz , Modelos Teóricos , Espalhamento de Radiação
13.
Biomed Res Int ; 2018: 3561962, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29998132

RESUMO

We aimed to characterize female athlete's heart in elite competitors in the International Federation of Bodybuilding and Fitness (IFBB) Bikini Fitness category and compare them to athletes of a more dynamic sport discipline and healthy, sedentary volunteers using 3D echocardiography. Fifteen elite female fitness athletes were recruited and compared to 15 elite, age-matched female water polo athletes and 15 age-matched healthy, nontrained controls. Using 3D echocardiography, left ventricular (LV) and right ventricular (RV) end-diastolic volume index (EDVi) and LV mass index (LVMi) were measured. Fitness athletes presented similar LV and RV EDVi compared to healthy, sedentary volunteers. Water polo athletes, however, had higher LV and also RV EDVi (fitness versus water polo versus control; LVEDVi: 76 ± 13 versus 84 ± 8 versus 73 ± 8 ml/m2, ANOVA p = 0.045; RVEDVi: 61 ± 12 versus 86 ± 14 versus 55 ± 9 ml/m2, p < 0.0001). LVMi was significantly higher in the athlete groups; the hypertrophy, however, was even more prominent in water polo athletes (78 ± 13 versus 91 ± 10 versus 57 ± 10 g/m2, p < 0.0001). To the best of our knowledge, this is the first study to characterize female athlete's heart of IFBB Bikini Fitness competitors. The predominantly static exercise regime induced a mild, concentric-type LV hypertrophy, while in water polo athletes higher ventricular volumes and eccentric LV hypertrophy developed.


Assuntos
Atletas , Ecocardiografia , Coração/anatomia & histologia , Adulto , Estudos de Casos e Controles , Ecocardiografia Tridimensional , Exercício Físico , Feminino , Coração/diagnóstico por imagem , Ventrículos do Coração , Humanos , Esportes , Adulto Jovem
14.
Leg Med (Tokyo) ; 23: 59-70, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27890106

RESUMO

Craniofacial superimposition has the potential to be used as an identification method when other traditional biological techniques are not applicable due to insufficient quality or absence of ante-mortem and post-mortem data. Despite having been used in many countries as a method of inclusion and exclusion for over a century it lacks standards. Thus, the purpose of this research is to provide forensic practitioners with standard criteria for analysing skull-face relationships. Thirty-seven experts from 16 different institutions participated in this study, which consisted of evaluating 65 criteria for assessing skull-face anatomical consistency on a sample of 24 different skull-face superimpositions. An unbiased statistical analysis established the most objective and discriminative criteria. Results did not show strong associations, however, important insights to address lack of standards were provided. In addition, a novel methodology for understanding and standardizing identification methods based on the observation of morphological patterns has been proposed.


Assuntos
Face/anatomia & histologia , Antropologia Forense/métodos , Imageamento Tridimensional , Fotografação , Crânio/anatomia & histologia , Autopsia , Humanos
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