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1.
Opt Express ; 32(5): 7720-7730, 2024 Feb 26.
Artículo en Inglés | MEDLINE | ID: mdl-38439447

RESUMEN

Hollow-core optical fibers can offer broadband, single mode guidance in the UV-visible-NIR wavelength range, with the potential for low-loss, solarization-free operation, making them desirable and potentially disruptive for a wide range of applications. To achieve this requires the fabrication of fibers with <300nm anti-resonant membranes, which is technically challenging. Here we investigate the underlying fluid dynamics of the fiber fabrication process and demonstrate a new three-stage fabrication approach, capable of delivering long (∼350m) lengths of fiber with the desired thin-membranes.

2.
Curr Opin Cardiol ; 39(3): 202-209, 2024 05 01.
Artículo en Inglés | MEDLINE | ID: mdl-38375816

RESUMEN

PURPOSE OF REVIEW: This review addresses the evolving intersection of sleep-disordered breathing (SDB) and heart failure, a topic of increasing clinical significance due to the high prevalence of SDB in heart failure patients and its impact on morbidity and mortality. It reflects recent advancements in diagnostic methodologies and therapeutic strategies. It emphasizes the need for heightened awareness among healthcare providers about the complex relationship between SDB and various forms of heart failure. RECENT FINDINGS: Recent studies underscore the high incidence of SDB in heart failure patients, varying with the cause of heart failure. Emerging diagnostic tools, including home sleep tests and advanced inpatient screening methods, have improved the early detection and accurate diagnosis of SDB. Novel treatment modalities, like hypoglossal and phrenic nerve stimulation, are promising, especially where conventional therapies are inadequate. The review also discusses the complexities of managing SDB in the context of different heart failure subtypes. SUMMARY: Findings from recent literature suggest that improved screening, diagnosis, and innovative treatment of SDB in heart failure patients can reduce morbidity, mortality, and healthcare costs. This review emphasizes the need for personalized treatment approaches tailored to individual patient profiles, highlighting the potential of new technologies and multidisciplinary strategies in clinical practice.


Asunto(s)
Insuficiencia Cardíaca , Síndromes de la Apnea del Sueño , Humanos , Síndromes de la Apnea del Sueño/complicaciones , Síndromes de la Apnea del Sueño/diagnóstico , Síndromes de la Apnea del Sueño/epidemiología , Insuficiencia Cardíaca/complicaciones , Insuficiencia Cardíaca/terapia
3.
Artif Organs ; 48(2): 191-196, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37974550

RESUMEN

Sleep-disordered breathing, including obstructive sleep apnea (OSA) and central sleep apnea (CSA), is common in severe heart failure (HF) patients. There is limited data on the effect of left ventricular assist devices (LVAD) on sleep apnea. We performed a retrospective review of 350 durable LVAD patients and found 5 with a history of pre- and post-LVAD sleep studies. All five patients had OSA, and three had concomitant CSA. We observed reduced apnea-hypopnea index following LVAD placement. This was due to a near abolishment of CSA in three mixed sleep apnea patients-as seen by a central apnea index improvement from an average of 25.9 ± 13.1 to 1.4 ± 2.5 events per hour (p = 0.063). LVAD placement was associated with an increase in thermodilution cardiac output from 2.7 ± 0.6 to 4.1 ± 1.1 L/min (p = 0.014). These findings support chemoreception physiology seen in patients with poor circulation and the effect of restoring this circulation with LVAD support.


Asunto(s)
Insuficiencia Cardíaca , Corazón Auxiliar , Síndromes de la Apnea del Sueño , Apnea Central del Sueño , Apnea Obstructiva del Sueño , Humanos , Encéfalo , Insuficiencia Cardíaca/complicaciones , Insuficiencia Cardíaca/cirugía , Corazón Auxiliar/efectos adversos , Síndromes de la Apnea del Sueño/complicaciones , Síndromes de la Apnea del Sueño/terapia , Apnea Central del Sueño/complicaciones , Apnea Obstructiva del Sueño/complicaciones , Apnea Obstructiva del Sueño/terapia
4.
J Card Fail ; 29(9): 1288-1295, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37230313

RESUMEN

BACKGROUND: Heart transplantation is the gold-standard therapy for end-stage heart failure, but rates of donor-heart use remain low due to various factors that are often not evidence based. The impact of donor hemodynamics obtained via right-heart catheterization on recipient survival remains unclear. METHODS: The United Network for Organ Sharing registry was used to identify donors and recipients from September 1999-December 2019. Donor hemodynamics data were obtained and analyzed using univariate and multivariable logistical regression, with the primary endpoints being 1- and 5-year post-transplant survival. RESULTS: Of the 85,333 donors who consented to heart transplantation during the study period, 6573 (7.7%) underwent right-heart catheterization, of whom 5531 eventually underwent procurement and transplantation. Donors were more likely to undergo right-heart catheterization if they had high-risk criteria. Recipients who had donor hemodynamic assessment had 1- and 5-year survival rates similar to those without donor hemodynamic assessment (87% vs 86%, 1 year). Abnormal hemodynamics were common in donor hearts but did not impact recipient survival rates, even when risk-adjusted in multivariable analysis. CONCLUSIONS: Donors with abnormal hemodynamics may represent an opportunity to expand the pool of viable donor hearts.


Asunto(s)
Insuficiencia Cardíaca , Trasplante de Corazón , Humanos , Donantes de Tejidos , Insuficiencia Cardíaca/cirugía , Hemodinámica , Sistema de Registros , Estudios Retrospectivos
5.
Sensors (Basel) ; 23(20)2023 Oct 11.
Artículo en Inglés | MEDLINE | ID: mdl-37896489

RESUMEN

Hand-function recovery is often a goal for stroke survivors undergoing therapy. This work aimed to design, build, and verify a pneumatic hand training device for its eventual use in post-stroke rehabilitation. The system was built considering prior research in the field of robotic hand rehabilitation as well as specifications and design constraints developed with physiotherapists. The system contained pneumatic airbag actuators for the fingers and thumb of the hand, a set of flex, pressure, and flow sensors, and software and hardware controls. An experiment with the system was carried out on 30 healthy individuals. The sensor readings were analyzed for repeatability and reliability. Position sensors and an approximate biomechanical model of the index finger were used to estimate joint angles during operation. A survey was also issued to the users to evaluate their comfort levels with the device. It was found that the system was safe and comfortable when moving the fingers of the hand into an extension.


Asunto(s)
Dispositivo Exoesqueleto , Procedimientos Quirúrgicos Robotizados , Rehabilitación de Accidente Cerebrovascular , Humanos , Reproducibilidad de los Resultados , Diseño de Equipo , Mano , Dedos
6.
Biomed Instrum Technol ; 55(3): 103-111, 2021 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-34460906

RESUMEN

OBJECTIVE: We sought to explore the technical and legal readiness of healthcare institutions for novel data-sharing methods that allow clinical information to be extracted from electronic health records (EHRs) and submitted securely to the Food and Drug Administration's (FDA's) blockchain through a secure data broker (SDB). MATERIALS AND METHODS: This assessment was divided into four sections: an institutional EHR readiness assessment, legal consultation, institutional review board application submission, and a test of healthcare data transmission over a blockchain infrastructure. RESULTS: All participating institutions reported the ability to electronically extract data from EHRs for research. Formal legal agreements were deemed unnecessary to the project but would be needed in future tests of real patient data exchange. Data transmission to the FDA blockchain met the success criteria of data connection from within the four institutions' firewalls, externally to the FDA blockchain via a SDB. DISCUSSION: The readiness survey indicated advanced analytic capability in hospital institutions and highlighted inconsistency in Fast Healthcare Interoperability Resources format utilitzation across institutions, despite requirements of the 21st Century Cures Act. Further testing across more institutions and annual exercises leveraging the application of data exchange over a blockchain infrastructure are recommended actions for determining the feasibility of this approach during a public health emergency and broaden the understanding of technical requirements for multisite data extraction. CONCLUSION: The FDA's RAPID (Real-Time Application for Portable Interactive Devices) program, in collaboration with Discovery, the Critical Care Research Network's PREP (Program for Resilience and Emergency Preparedness), identified the technical and legal challenges and requirements for rapid data exchange to a government entity using the FDA blockchain infrastructure.


Asunto(s)
Cadena de Bloques , Registros Electrónicos de Salud , Urgencias Médicas , Humanos , Salud Pública , Evaluación de la Tecnología Biomédica , Estados Unidos
7.
J Card Fail ; 26(12): 1096-1099, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-33035683

RESUMEN

BACKGROUND: The physiologic factors leading to pulmonary arterial wedge pressure respiratory variation (PAWPvar) are underexplored. We hypothesized that PAWPvar is associated with baseline PAWP and would predict response to sodium nitroprusside (SNP). METHODS AND RESULTS: We performed a retrospective study of right heart catheterization studies in 51 subjects with SNP challenge at our institution from 2012 to 2019. PAWPvar was defined as expiratory minus inspiratory PAWP. Baseline %PAWPvar was inversely correlated with baseline PAWP (R = -0.5). SNP administration led to increased %PAWPvar (+27%, P < .01). Subjects with low baseline PAWPvar (less than the median) had an increase in PAWPvar with SNP (3 ± 4 mm Hg), whereas those with a high baseline PAWPvar (greater than the median) did not (-0.6 ± 4 mm Hg, P = .003). Those who had a greater than the median PAWPvar increase with SNP had greater cardiac output augmentation compared with those who had less than a median increase in PAWPvar (1.7 ± 1.5 L/min vs 0.9 ± 0.7 L/min, P = .02). An increasing PAWPvar after SNP was associated with significant discrepancy in the number of subjects achieving transplant-acceptable pulmonary vascular resistance (<2.5 Wood units) when calculated by expiratory versus mean PAWP (37 vs 27 subjects, 20% discrepancy rate). Subjects with a higher PAWPvar after SNP were more likely to demonstrate discrepant transplant-acceptable pulmonary vascular resistance calculations comparing expiratory versus mean PAWP than those with lower PAWPvar post-SNP (47% vs 13%, odds ratio 5.5, P = .03). CONCLUSIONS: Our findings indicate that PAWPvar is a meaningful physiologic parameter that is influenced by the compliance of the left heart/pulmonary vascular system and its relative preload and afterload states.


Asunto(s)
Insuficiencia Cardíaca , Vasodilatadores , Hemodinámica , Humanos , Nitroprusiato/farmacología , Arteria Pulmonar , Presión Esfenoidal Pulmonar , Estudios Retrospectivos , Resistencia Vascular , Vasodilatadores/farmacología
8.
Bioorg Med Chem Lett ; 30(21): 127575, 2020 11 01.
Artículo en Inglés | MEDLINE | ID: mdl-32980511

RESUMEN

ß-Lactam antibiotics have for long been a mainstay in antimicrobial chemotherapy. However, due to its ubiquitous usage, bacteria have evolved multiple concerted pathways to evade its actions, underscoring the complexity of resistance to this class of drug. Current strategies to mitigate this problem are geared towards developing inhibitors that can shield the ß-lactam core from enzymatic hydrolysis. In reality, a combination of factors including porin loss, overexpressed efflux pumps, expression of ß-lactamases, reduced outer membrane permeability, and target modifications are characteristics of phenotypes that are microbiologically resistant to ß-lactam antibiotics, especially Pseudomonas aeruginosa. Herein, we describe a strategy that may simultaneously address multiple mechanisms of resistance to ß-lactams. A triple combination with ß-lactam/ß-lactamase inhibitors offers better microbiological response against carbapenem-resistant P. aeruginosa than the current standard of care. The observed interactions are also unaffected by efflux pumps. We conclude that a multicomponent combination therapy may be the way forward in addressing the myriads of emerging therapy failure associated with ß-lactam resistance.


Asunto(s)
Antibacterianos/farmacología , Pseudomonas aeruginosa/efectos de los fármacos , Tobramicina/farmacología , Resistencia betalactámica/efectos de los fármacos , Antibacterianos/síntesis química , Antibacterianos/química , Relación Dosis-Respuesta a Droga , Pruebas de Sensibilidad Microbiana , Estructura Molecular , Relación Estructura-Actividad , Tobramicina/síntesis química , Tobramicina/química , beta-Lactamas/farmacología
9.
Phys Chem Chem Phys ; 22(1): 136-143, 2019 Dec 18.
Artículo en Inglés | MEDLINE | ID: mdl-31793940

RESUMEN

Three BaZr0.9Y0.1O3-δ (BZY10) pellets were prepared using different sintering processes, resulting in samples with different grain sizes, from 0.3 to 5 microns. Ambient pressure X-ray photoelectron spectra were recorded in argon, steam and oxygen atmospheres (100 mTorr) in the 300-500 °C temperature range. Deconvolution of O 1s peaks reveals 4 distinct contributions: sub-surface lattice oxide, termination layer oxides, OH- and gas-phase steam in wet environments. The OH- contribution of the O 1s peak includes sub-surface incorporation of protonic defects in the lattice related to hydration as well as surface hydroxylation and molecular water adsorption. The OH- concentration increases with grain size and with decreasing the analysis depth. These results suggest that grain boundaries associated with the larger grains adsorbed water more effectively. Thus, larger grains, which increase proton conductivity in BZY10, may also enhance catalytic activity for carbonaceous fuel oxidation by facilitating increased hydration and surface carbon removal.

10.
Retina ; 37(7): 1329-1336, 2017 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-28633153

RESUMEN

PURPOSE: To examine the association between subretinal drusenoid deposits (SDDs) identified by multimodal retinal imaging and visual function in older eyes with normal macular health or in the earliest phases of age-related macular degeneration (AMD). METHODS: Age-related macular degeneration status for each eye was defined according to the Age-Related Eye Disease Study (AREDS) 9-step classification system (normal = Step 1, early AMD = Steps 2-4) based on color fundus photographs. Visual functions measured were best-corrected photopic visual acuity, contrast and light sensitivity, mesopic visual acuity, low-luminance deficit, and rod-mediated dark adaptation. Subretinal drusenoid deposits were identified through multimodal imaging (color fundus photographs, infrared reflectance and fundus autofluorescence images, and spectral domain optical coherence tomography). RESULTS: The sample included 1,202 eyes (958 eyes with normal health and 244 eyes with early AMD). In normal eyes, SDDs were not associated with any visual function evaluated. In eyes with early AMD, dark adaptation was markedly delayed in eyes with SDDs versus no SDD (a 4-minute delay on average), P = 0.0213. However, this association diminished after age adjustment, P = 0.2645. Other visual functions in early AMD eyes were not associated with SDDs. CONCLUSION: In a study specifically focused on eyes in normal macular health and in the earliest phases of AMD, early AMD eyes with SDDs have slower dark adaptation, largely attributable to the older ages of eyes with SDD; they did not exhibit deficits in other visual functions. Subretinal drusenoid deposits in older eyes in normal macular health are not associated with any visual functions evaluated.


Asunto(s)
Adaptación a la Oscuridad , Mácula Lútea/patología , Drusas Retinianas/etiología , Tomografía de Coherencia Óptica/métodos , Agudeza Visual , Degeneración Macular Húmeda/complicaciones , Anciano , Anciano de 80 o más Años , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Drusas Retinianas/diagnóstico , Drusas Retinianas/fisiopatología , Degeneración Macular Húmeda/diagnóstico , Degeneración Macular Húmeda/fisiopatología
11.
Ophthalmology ; 123(2): 344-351, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26522707

RESUMEN

PURPOSE: To examine whether slowed rod-mediated dark adaptation (DA) in adults with normal macular health at baseline is associated with the incidence of age-related macular degeneration (AMD) 3 years later. DESIGN: Prospective cohort. PARTICIPANTS: Adults aged ≥60 years were recruited from primary care ophthalmology clinics. Both eyes were required to be step 1 (normal) on the Age-Related Eye Disease Study 9-step AMD classification system based on color fundus photographs graded by experienced and masked evaluators. METHODS: Rod-mediated DA was assessed at baseline in 1 eye after a photobleach using a computerized dark adaptometer with targets centered at 5° on the inferior vertical meridian. Speed of DA was characterized by the rod-intercept value, with abnormal DA defined as rod-intercept ≥12.3 minutes. Demographic characteristics, best-corrected visual acuity, and smoking status were also assessed. Log-binomial regression was used to calculate unadjusted and adjusted risk ratios (RRs) and associated 95% confidence intervals (CIs) for the association between baseline DA and incident AMD. MAIN OUTCOME MEASURES: Presence of AMD at the 3-year follow-up visit for the eye tested for DA at baseline. RESULTS: Both baseline and follow-up visits were completed by 325 persons (mean age, 67.8 years). At baseline, 263 participants had normal DA with mean rod-intercept of 9.1 (standard deviation [SD], 1.5), and 62 participants had abnormal DA with mean rod-intercept of 15.1 (SD, 4.0). After adjustment for age and smoking, those with abnormal DA in the tested eye at baseline were approximately 2 times more likely to have AMD in that eye (RR, 1.92; 95% CI, 1.03-3.62) by the time of the follow-up visit, compared with those who had normal DA at baseline. CONCLUSIONS: Delayed rod-mediated DA in older adults with normal macular health is associated with incident early AMD 3 years later, and thus is a functional biomarker for early disease. The biological relevance of this test is high, because it assesses translocation of vitamin A derivatives across the retinal pigment epithelium and Bruch's membrane, 2 tissues with prominent age- and AMD-related pathology.


Asunto(s)
Biomarcadores , Adaptación a la Oscuridad/fisiología , Degeneración Macular/diagnóstico , Degeneración Macular/fisiopatología , Células Fotorreceptoras Retinianas Bastones/fisiología , Anciano , Anciano de 80 o más Años , Diagnóstico Precoz , Femenino , Humanos , Degeneración Macular/clasificación , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Agudeza Visual/fisiología
12.
BMC Ophthalmol ; 16: 105, 2016 Jul 11.
Artículo en Inglés | MEDLINE | ID: mdl-27401722

RESUMEN

BACKGROUND: Dark adaptation is an energy-requiring process in the outer retina nourished by the profusely perfused choroid. We hypothesized that variations in choroidal thickness might affect the rate of dark adaptation. METHOD: Cross-sectional, observational study of 42 healthy university students (mean age 25 ± 2.0 years, 29 % men) who were examined using an abbreviated automated dark adaptometry protocol with a 2° diameter stimulus centered 5° above the point of fixation. The early, linear part of the rod-mediated dark adaptation curve was analyzed to extract the time required to reach a sensitivity of 5.0 × 10(-3) cd/m2 (time to rod intercept) and the slope (rod adaptation rate). The choroid was imaged using enhanced-depth imaging spectral-domain optical coherence tomography (EDI-OCT). RESULTS: The time to the rod intercept was 7.3 ± 0.94 (range 5.1 - 10.2) min. Choroidal thickness 2.5° above the fovea was 348 ± 104 (range 153-534) µm. There was no significant correlation between any of the two measures of rod-mediated dark adaptation and choroidal thickness (time to rod intercept versus choroidal thickness 0.072 (CI95 -0.23 to 0.38) min/100 µm, P = 0.64, adjusted for age and sex). There was no association between the time-to-rod-intercept or the dark adaptation rate and axial length, refraction, gender or age. CONCLUSION: Choroidal thickness, refraction and ocular axial length had no detectable effect on rod-mediated dark adaptation in healthy young subjects. Our results do not support that variations in dark adaptation can be attributed to variations in choroidal thickness.


Asunto(s)
Coroides/anatomía & histología , Adaptación a la Oscuridad/fisiología , Adulto , Factores de Edad , Longitud Axial del Ojo/fisiología , Presión Sanguínea/fisiología , Estudios Transversales , Femenino , Humanos , Masculino , Refracción Ocular/fisiología , Células Fotorreceptoras Retinianas Bastones/fisiología , Umbral Sensorial/fisiología , Factores Sexuales , Factores de Tiempo , Tomografía de Coherencia Óptica/métodos , Agudeza Visual , Adulto Joven
13.
Socioecon Rev ; 19(1): 1-6, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34393661
14.
Ophthalmology ; 122(5): 957-67, 2015 May.
Artículo en Inglés | MEDLINE | ID: mdl-25601533

RESUMEN

PURPOSE: To identify changes in retinal function and structure in persons with proliferative diabetic retinopathy (PDR), including the effects of panretinal photocoagulation (PRP). DESIGN: Cross-sectional study. PARTICIPANTS: Thirty adults who underwent PRP for PDR, 15 adults with untreated PDR, and 15 age-matched controls. METHODS: Contrast sensitivity, frequency doubling perimetry (FDP), Humphrey visual fields, photostress recovery, and dark adaptation were assessed. Fundus photography and macular spectral-domain optical coherence tomography (SD OCT) were performed. To quantify retinal layer thicknesses, SD OCT scans were segmented semiautomatically. MAIN OUTCOME MEASURES: Visual function measures were compared among patients with PDR and PRP, untreated patients with PDR, and controls. Mean retinal layer thicknesses were compared between groups. Correlation analyses were performed to evaluate associations between visual function measures and retinal layer thicknesses. RESULTS: A significant reduction of FDP mean deviation (MD) was exhibited in PRP-treated patients with PDR (MD ± standard deviation, -8.20±5.76 dB; P < 0.0001) and untreated patients (-5.48±4.48 dB; P < 0.0001) relative to controls (1.07±2.50 dB). Reduced log contrast sensitivity compared with controls (1.80±0.14) also was observed in both PRP-treated patients (1.42±0.17; P < 0.0001) and untreated patients (1.56±0.20; P = 0.001) with PDR. Compared with controls, patients treated with PRP demonstrated increased photostress recovery time (151.02±104.43 vs. 70.64±47.14 seconds; P = 0.001) and dark adaptation speed (12.80±5.15 vs. 9.74±2.56 minutes; P = 0.022). Patients who underwent PRP had diffusely thickened nerve fiber layers (P = 0.024) and diffusely thinned retinal pigment epithelium (RPE) layers (P = 0.009) versus controls. Untreated patients with PDR also had diffusely thinned RPE layers (P = 0.031) compared with controls. CONCLUSIONS: Patients with untreated PDR exhibited inner retinal dysfunction, as evidenced by reduced contrast sensitivity and FDP performance, accompanied by alterations in inner and outer retinal structure. Patients who underwent PRP had more profound changes in outer retinal structure and function. Distinguishing the effects of PDR and PRP may guide the development of restorative vision therapies for patients with advanced diabetic retinopathy.


Asunto(s)
Retinopatía Diabética/diagnóstico , Retina/fisiopatología , Neovascularización Retiniana/diagnóstico , Sensibilidad de Contraste/fisiología , Estudios Transversales , Adaptación a la Oscuridad , Diabetes Mellitus Tipo 1/complicaciones , Diabetes Mellitus Tipo 2/complicaciones , Retinopatía Diabética/fisiopatología , Retinopatía Diabética/cirugía , Femenino , Humanos , Coagulación con Láser , Masculino , Persona de Mediana Edad , Imagen Multimodal , Neovascularización Retiniana/fisiopatología , Neovascularización Retiniana/cirugía , Tomografía de Coherencia Óptica , Agudeza Visual/fisiología , Pruebas del Campo Visual , Campos Visuales/fisiología
15.
Am J Perinatol ; 32(10): 944-51, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-25738788

RESUMEN

OBJECTIVE: The aim of this study is to determine whether a transcutaneous bilirubin (TcB) value obtained within 6 hours of birth (early transcutaneous bilirubin [ETcB]) either alone, or used to calculate an early rate of rise (E-ROR) in TcB, will identify those neonates who are at a higher risk for subsequent jaundice. STUDY DESIGN: ETcB values were obtained from a convenience sample of neonates admitted to the newborn nursery. E-ROR was calculated as the average hourly increase between ETcB and subsequent TcB obtained at 18 to 36 hours of age. TcB percentile values at various ages were obtained from a previously published and cross-validated nomogram. The predictive values relating ETcB, E-ROR, and TcB at 18 to 36 hours of age to TcB at 42 to 66 hours of age were determined, and receiver-operator characteristic curves were compared. RESULTS: A total of 516 late preterm and term neonates were studied. ETcB was higher (p = 0.003) in those neonates who subsequently received phototherapy (n = 15), and negative predictive value was always ≥ 0.96; positive predictive value (PPV) ranged from 0.04 to 0.06. Compared with ETcB, TcB at 18 to 36 hours was more likely to predict significant jaundice at 42 to 66 hours of age. CONCLUSION: Given the observed low PPV, ETcB is not useful in identifying infants who develop subsequent hyperbilirubinemia. However, it may be helpful in identifying those neonates at a low risk of subsequent hyperbilirubinemia.


Asunto(s)
Bilirrubina/análisis , Hiperbilirrubinemia Neonatal/diagnóstico , Estudios de Cohortes , Diagnóstico Precoz , Femenino , Humanos , Hiperbilirrubinemia Neonatal/terapia , Recién Nacido , Masculino , Tamizaje Neonatal/métodos , Fototerapia , Valor Predictivo de las Pruebas , Curva ROC , Medición de Riesgo
16.
Phys Chem Chem Phys ; 16(27): 14271-80, 2014 Jul 21.
Artículo en Inglés | MEDLINE | ID: mdl-24914875

RESUMEN

Zirconium-doped ceria (Ce(1-x)Zr(x)O2) was synthesized through a controlled electrospinning process as a promising approach to cost-effective, sinter-resistant material structures for high-temperature, solar-driven thermochemical redox cycles. To approximate a two-step redox cycle for solar fuel production, fibrous Ce(1-x)Zr(x)O2 with relatively low levels of Zr-doping (0 < x < 0.1) were cycled in an infrared-imaging furnace with high-temperature (up to 1500 °C) partial reduction and lower-temperature (∼800 °C) reoxidation via CO2 splitting to produce CO. Increases in Zr content improve reducibility and sintering resistance, and, for x≤ 0.05, do not significantly slow reoxidation kinetics for CO production. Cycle stability of the fibrous Ce(1-x)Zr(x)O2 (with x = 0.025) was assessed for a range of conditions by measuring rates of O2 release during reduction and CO production during reoxidation and by assessing post-cycling fiber crystallite sizes and surface areas. Sintering increases with reduction temperature but occurs primarily along the fiber axes. Even after 108 redox cycles with reduction at 1400 °C and oxidation with CO2 at 800 °C, the fibers maintain their structure with surface areas of ∼0.3 m(2) g(-1), higher than those observed in the literature for other ceria-based structures operating at similarly high temperature conditions. Total CO production and peak production rate stabilize above 3.0 mL g(-1) and 13.0 mL min(-1) g(-1), respectively. The results show the potential for electrospun oxides as sinter-resistant material structures with adequate surface area to support rapid CO2 splitting in solar thermochemical redox cycles.

17.
Optom Vis Sci ; 91(8): 925-31, 2014 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-24705482

RESUMEN

PURPOSE: A sensitive endpoint is required for clinical trials evaluating preventative therapies for early age-related macular degeneration (AMD). Dark adaptation (DA) is a sensitive marker of AMD and has been proposed as a potential endpoint. This study evaluated whether significant changes in DA speed could be detected in participants with early to intermediate AMD at 12 months following baseline DA measurement. METHODS: Dark adaptation, visual acuity (VA), and fundus photography were obtained at baseline and at 6 and 12 months in 26 subjects with AMD and in 6 subjects with normal retinal health. Disease severity was assessed by the Nine-Step Age-Related Eye Disease Study AMD severity scale. RESULTS: At 12 months, significant progression of DA impairment occurred in 5 of 26 (19%) participants with AMD. None of the participants with AMD exhibited a significant worsening of fundus grade or decrease of acuity related to disease progression. The normal group exhibited stable DA and VA during the observation period. CONCLUSIONS: Significant worsening of DA was observed in 19% of subjects with AMD in 12 months of observation, despite stable VA and fundus appearance. This study suggests that DA may be a suitable functional endpoint for early clinical studies evaluating novel treatments for early to intermediate AMD.


Asunto(s)
Adaptación a la Oscuridad/fisiología , Degeneración Macular/fisiopatología , Retina/fisiopatología , Trastornos de la Visión/fisiopatología , Agudeza Visual/fisiología , Anciano , Anciano de 80 o más Años , Progresión de la Enfermedad , Determinación de Punto Final , Femenino , Humanos , Degeneración Macular/diagnóstico , Masculino , Persona de Mediana Edad , Umbral Sensorial
18.
ASAIO J ; 70(2): 99-106, 2024 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-37816019

RESUMEN

Right ventricular failure contributes significantly to morbidity and mortality after left ventricular assist device implantation. Recent data suggest a less invasive strategy (LIS) via thoracotomy may be associated with less right ventricular failure than conventional median sternotomy (CMS). However, the impact of these approaches on load-independent right ventricular (RV) contractility and RV-pulmonary arterial (RV-PA) coupling remains uncertain. We hypothesized that the LIS approach would be associated with preserved RV contractility and improved RV-PA coupling compared with CMS. We performed a retrospective study of patients who underwent durable, centrifugal left ventricular assist device implantation and had paired hemodynamic assessments before and after implantation. RV contractility (end-systolic elastance [Ees]), RV afterload (pulmonary effective arterial elastance [Ea]), and RV-PA coupling (Ees/Ea) were determined using digitized RV pressure waveforms. Forty-two CMS and 21 LIS patients were identified. Preimplant measures of Ees, Ea, and Ees/Ea were similar between groups. After implantation, Ees declined significantly in the CMS group (0.60-0.40, p = 0.008) but not in the LIS group (0.67-0.58, p = 0.28). Coupling (Ees/Ea) was unchanged in CMS group (0.54-0.59, p = 0.80) but improved significantly in the LIS group (0.58-0.71, p = 0.008). LIS implantation techniques may better preserve RV contractility and improve RV-PA coupling compared with CMS.


Asunto(s)
Insuficiencia Cardíaca , Corazón Auxiliar , Hipertensión Pulmonar , Disfunción Ventricular Derecha , Humanos , Estudios Retrospectivos , Arteria Pulmonar , Ventrículos Cardíacos , Insuficiencia Cardíaca/cirugía
19.
J Am Heart Assoc ; 13(6): e031029, 2024 Mar 19.
Artículo en Inglés | MEDLINE | ID: mdl-38471835

RESUMEN

BACKGROUND: Recurrence after atrial fibrillation (AF) ablation remains common. We evaluated the association between recurrence and levels of biomarkers of cardiac remodeling, and their ability to improve recurrence prediction when added to a clinical prediction model. METHODS AND RESULTS: Blood samples collected before de novo catheter ablation were analyzed. Levels of bone morphogenetic protein-10, angiopoietin-2, fibroblast growth factor-23, insulin-like growth factor-binding protein-7, myosin-binding protein C3, growth differentiation factor-15, interleukin-6, N-terminal pro-brain natriuretic peptide, and high-sensitivity troponin T were measured. Recurrence was defined as ≥30 seconds of an atrial arrhythmia 3 to 12 months postablation. Multivariable logistic regression was performed using biomarker levels along with clinical covariates: APPLE score (Age >65 years, Persistent AF, imPaired eGFR [<60 ml/min/1.73m2], LA diameter ≥43 mm, EF <50%; which includes age, left atrial diameter, left ventricular ejection fraction, persistent atrial fibrillation, and estimated glomerular filtration rate), preablation rhythm, sex, height, body mass index, presence of an implanted continuous monitor, year of ablation, and additional linear ablation. A total of 1873 participants were included. A multivariable logistic regression showed an association between recurrence and levels of angiopoietin-2 (odds ratio, 1.08 [95% CI, 1.02-1.15], P=0.007) and interleukin-6 (odds ratio, 1.02 [95% CI, 1.003-1.03]; P=0.02). The area under the receiver operating characteristic curve of a model that only contained clinical predictors was 0.711. The addition of any of the 9 studied biomarkers to the predictive model did not result in a statistically significant improvement in the area under the receiver operating characteristic curve. CONCLUSIONS: Higher angiopoietin-2 and interleukin-6 levels were associated with recurrence after atrial fibrillation ablation in multivariable modeling. However, the addition of biomarkers to a clinical prediction model did not significantly improve recurrence prediction.


Asunto(s)
Fibrilación Atrial , Remodelación Atrial , Ablación por Catéter , Humanos , Anciano , Fibrilación Atrial/diagnóstico , Fibrilación Atrial/cirugía , Angiopoyetina 2 , Interleucina-6 , Modelos Estadísticos , Volumen Sistólico , Remodelación Ventricular , Factores de Riesgo , Pronóstico , Recurrencia , Función Ventricular Izquierda , Biomarcadores , Ablación por Catéter/efectos adversos , Ablación por Catéter/métodos , Resultado del Tratamiento
20.
Artículo en Inglés | MEDLINE | ID: mdl-39243256

RESUMEN

BACKGROUND: Patients with rare, pathogenic cardiomyopathy (CM) and arrhythmia variants can present with atrial fibrillation (AF). The efficacy of AF ablation in these patients is unknown. OBJECTIVE: This study tested the hypotheses that: 1) patients with a pathogenic variant in any CM or arrhythmia gene have increased recurrence following AF ablation; and 2) patients with a pathogenic variant associated with a specific gene group (arrhythmogenic left ventricular CM [ALVC], arrhythmogenic right ventricular CM, dilated CM, hypertrophic CM, or a channelopathy) have increased recurrence. METHODS: We performed a prospective, observational, cohort study of patients who underwent AF catheter ablation and whole exome sequencing. The primary outcome measure was ≥30 seconds of any atrial tachyarrhythmia that occurred after a 90-day blanking period. RESULTS: Among 1,366 participants, 109 (8.0%) had a pathogenic or likely pathogenic (P/LP) variant in a CM or arrhythmia gene. In multivariable analysis, the presence of a P/LP variant in any gene was not significantly associated with recurrence (HR 1.15; 95% CI 0.84-1.60; P = 0.53). P/LP variants in the ALVC gene group, predominantly LMNA, were associated with increased recurrence (n = 10; HR 3.75; 95% CI 1.84-7.63; P < 0.001), compared with those in the arrhythmogenic right ventricular CM, dilated CM, hypertrophic CM, and channelopathy gene groups. Participants with P/LP TTN variants (n = 46) had no difference in recurrence compared with genotype-negative-controls (HR 0.93; 95% CI 0.54-1.59; P = 0.78). CONCLUSIONS: Our results support the use of AF ablation for most patients with rare pathogenic CM or arrhythmia variants, including TTN. However, patients with ALVC variants, such as LMNA, may be at a significantly higher risk for arrhythmia recurrence.

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