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1.
Invest Ophthalmol Vis Sci ; 65(8): 29, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-39023441

RESUMO

Purpose: To longitudinally investigate the changes in intraretinal microvascular abnormalities (IRMAs) over time, employing swept-source optical coherence tomography angiography in eyes with diabetic retinopathy. Methods: In this retrospective, longitudinal study, we evaluated 12 × 12-mm swept-source optical coherence tomography angiography centered on the macula at baseline and last available follow-up visit for (1) IRMA changes during follow-up, defined as (a) stable, (b) regressed, (c) obliterated, and (d) progressed; and the (2) development of new neovascularization (NV) and their origins. Competing-risk survival analysis was used to assess the factors associated with these changes. Results: In total, 195 eyes from 131 participants with diabetic retinopathy were included. Stable, regressed, obliterated, and progressed IRMA were observed in 65.1%, 12.8%, 11.3%, and 19% of eyes with diabetic retinopathy, respectively. Anti-VEGF injections during the follow-up periods and a slower increase of foveal avascular zone were associated with IRMA regression (P < 0.001 and P = 0.039). Obliterated IRMA were correlated with previous panretinal photocoagulation (P < 0.001) and a lower deep capillary plexus vessel density at baseline (P = 0.007), as well as with follow-up anti-VEGF injections (P = 0.025). A higher baseline ischemia index (ISI) and panretinal photocoagulation during the follow-up periods were associated with IRMA progression (P = 0.049 and P < 0.001). A faster increase in ISI predicted the development of NV elsewhere (NVE) from veins (P < 0.001). No significant factors were found to be associated with NVE originating from IRMA. Conclusions: Changes in IRMA closely correlated with the severity of retinal ischemia and treatment. Notably, our study confirmed the potential, yet relatively rare, development of NVE from IRMA in a large cohort; however, the risk factors associated with this transformation require further exploration.


Assuntos
Retinopatia Diabética , Angiofluoresceinografia , Vasos Retinianos , Tomografia de Coerência Óptica , Humanos , Tomografia de Coerência Óptica/métodos , Retinopatia Diabética/diagnóstico , Masculino , Estudos Retrospectivos , Feminino , Pessoa de Meia-Idade , Vasos Retinianos/patologia , Vasos Retinianos/diagnóstico por imagem , Angiofluoresceinografia/métodos , Seguimentos , Idoso , Neovascularização Retiniana/diagnóstico , Neovascularização Retiniana/diagnóstico por imagem , Acuidade Visual , Microvasos/patologia , Microvasos/diagnóstico por imagem , Fundo de Olho , Progressão da Doença , Estudos Longitudinais , Adulto
2.
Invest Ophthalmol Vis Sci ; 65(8): 21, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38990069

RESUMO

Purpose: We investigated the association between inner choroid flow deficit percentage (IC-FD%) using swept-source optical coherence tomography angiography (SS-OCTA) and progression of AMD. Methods: Retrospective, observational study including 64 eyes (42 participants) with early or intermediate AMD at baseline. Participants had two or more consecutive swept-source optical coherence tomography angiography covering a period of at least 18 months. Demographics, visual acuity, and AMD staging based on Beckman classification were reviewed. OCT was analyzed for hyperreflective foci, subretinal drusenoid deposits, hyporeflective drusen cores, and subfoveal choroidal thickness. IC-FD% was measured within the central 3- and 6-mm using a 16-µm slab, after compensation and binarization (Phansalkar method). Mixed-effects Cox regression models assessed the association between imaging biomarkers and AMD progression. Results: During follow-up (37 ± 9 months), 4 eyes with early AMD (31%) progressed to intermediate AMD and 30 (59%) eyes with intermediate AMD developed late AMD (19 geographic atrophy; 11 wet AMD). Baseline hyporeflective drusen core was associated with geographic atrophy development (P < 0.01), whereas greater IC-FD% (3-mm) was associated with wet AMD (P = 0.03). Time-varying analysis showed that faster subfoveal choroidal thickness reduction and IC-FD% (6-mm) increase were associated with geographic atrophy onset (P < 0.05), whereas IC-FD% (3-mm) increase was associated with wet AMD (P = 0.03). Notably, greater IC-FD% increases in the 3 mm (area under the curve = 0.72) and 6 mm (area under the curve = 0.89) were better predictive of wet AMD and geographic atrophy development, respectively. Conclusions: Our longitudinal IC-FD% assessment emphasizes the role of progressive choriocapillaris changes as a biomarker for AMD progression. Our findings support that widespread choriocapillaris alterations (6 mm) may precede progression to geographic atrophy, whereas more central choriocapillaris loss (3 mm) may provide an ischemic stimulus for wet AMD.


Assuntos
Corioide , Progressão da Doença , Angiofluoresceinografia , Tomografia de Coerência Óptica , Acuidade Visual , Humanos , Tomografia de Coerência Óptica/métodos , Corioide/irrigação sanguínea , Corioide/diagnóstico por imagem , Corioide/patologia , Masculino , Feminino , Estudos Retrospectivos , Idoso , Angiofluoresceinografia/métodos , Acuidade Visual/fisiologia , Idoso de 80 Anos ou mais , Pessoa de Meia-Idade , Seguimentos , Atrofia Geográfica/diagnóstico , Atrofia Geográfica/fisiopatologia , Atrofia Geográfica/diagnóstico por imagem , Drusas Retinianas/diagnóstico , Drusas Retinianas/diagnóstico por imagem , Degeneração Macular Exsudativa/diagnóstico , Degeneração Macular Exsudativa/fisiopatologia , Fundo de Olho
3.
Artigo em Inglês | MEDLINE | ID: mdl-38917397

RESUMO

BACKGROUND AND OBJECTIVE: To evaluate the association between widefield swept-source optical coherence tomography angiography (WF SS-OCTA) and visual function in healthy eyes. PATIENTS AND METHODS: Fifty-seven eyes of 45 patients were evaluated with visual acuity (VA), contrast sensitivity (CS), and WF SS-OCTA (3 × 3, 6 × 6, and 12 × 12 mm images) on the same day. Mixed-effects multivariable regression analyses were performed. RESULTS: Contrast sensitivity metrics, including CS between 6 to 18 cycles per degree (cpd) and area under the logarithm CS function, were significantly associated with vessel density (VD) and vessel skeletonized density (VSD), whereas VA was not. The largest effect size was between CS at 18 cpd and VD (ß = 0.41, P = 0.007) and VSD (ß = 0.42, P = 0.006) on 12 × 12 mm images. CONCLUSIONS: Reduced VSD and VD on WF SSOCTA was significantly associated with decreased CS, whereas VA was not. These results suggest CS could serve as a screening tool for early stage retinal and neurologic disorders. [Ophthalmic Surg Lasers Imaging Retina 2024;55:XX-XX.].

4.
Eur J Ophthalmol ; : 11206721241257553, 2024 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-38815990

RESUMO

PURPOSE: To report a case of progressive ischemic retinopathy and optic neuropathy in a patient with heavy chain deposition disease (HCDD), a rare form of monoclonal immunoglobulin deposition disease (MIDD). OBSERVATIONS: Our case describes a 74-year-old woman diagnosed with IgG1 lambda HCDD. After treatment with daratumumab and intravenous IVIG therapy, the patient developed worsening ischemic retinopathy and optic neuropathy, neovascular glaucoma, and bilateral sequential vitreous hemorrhages, necessitating surgical intervention. We present multimodal imaging from the onset of ischemic retinopathy to end-stage maculopathy illustrated by optical coherence tomography (OCT) angiography. Despite discontinuing treatment with daratumumab and providing maximal ocular interventions to control the complications of neovascular disease, the patient's condition progressed, resulting in profound vision loss. CONCLUSIONS AND IMPORTANCE: Our case illustrates the potential for HCDD to cause end-organ disease, including ischemic retinopathy and optic neuropathy, possibly worsened by the patient's underlying cardiovascular risk factor status and medications. Daratumumab, a humanized IgG1 kappa monoclonal antibody that binds to CD38 used to treat specific blood cancers, has been reported to cause disturbances in retinal blood flow, including retinal artery and vein occlusions. It remains to be determined whether careful patient selection or dose adjustments and timing of HCDD treatments could protect vision by reducing the risk of these rare yet severe ocular complications.

5.
Ophthalmic Surg Lasers Imaging Retina ; 55(7): 374-382, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38531003

RESUMO

BACKGROUND AND OBJECTIVE: Our objective was to assess baseline widefield swept-source optical coherence tomography angiography (WF SSOCTA) microvascular metrics as predictors for the number of anti-vascular endothelial growth factor (VEGF) injections and visual acuity (VA) at 12-months follow-up in patients with retinal vein occlusion (RVO). PATIENTS AND METHODS: This was a prospective study including 49 RVO eyes from 49 patients who had not received an anti-VEGF injection for at least 3 months prior to imaging. Microvascular metrics from 6×6-mm and 12×12-mm angiograms were assessed using linear regression models, adjusting for age. RESULTS: Reductions in the vessel density (VD) and vessel skeletonized density (VSD) vascular metrics were associated both with a higher number of anti-VEGF injections at all follow-up time points and reduced VA 12 months after imaging in all RVO eyes. CONCLUSIONS: WF SS-OCTA VD and VSD micro-vascular metrics at baseline can prognosticate VA and number of anti-VEGF injections required at 3, 6, and 12 months in RVO eyes. [Ophthalmic Surg Lasers Imaging Retina 2024;55:374-382.].


Assuntos
Inibidores da Angiogênese , Angiofluoresceinografia , Injeções Intravítreas , Oclusão da Veia Retiniana , Tomografia de Coerência Óptica , Fator A de Crescimento do Endotélio Vascular , Acuidade Visual , Humanos , Oclusão da Veia Retiniana/tratamento farmacológico , Oclusão da Veia Retiniana/diagnóstico , Tomografia de Coerência Óptica/métodos , Estudos Prospectivos , Inibidores da Angiogênese/uso terapêutico , Inibidores da Angiogênese/administração & dosagem , Masculino , Feminino , Fator A de Crescimento do Endotélio Vascular/antagonistas & inibidores , Angiofluoresceinografia/métodos , Idoso , Pessoa de Meia-Idade , Seguimentos , Vasos Retinianos/diagnóstico por imagem , Fundo de Olho , Ranibizumab/administração & dosagem , Ranibizumab/uso terapêutico , Idoso de 80 Anos ou mais
6.
Ophthalmic Surg Lasers Imaging Retina ; 55(4): 212-219, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38319059

RESUMO

BACKGROUND AND OBJECTIVE: We sought to establish normative quantitative contrast sensitivity function (qCSF) values in healthy adult eyes and investigate the effect of age on qCSF. PATIENTS AND METHODS: Healthy eyes underwent qCSF testing (adaptive sensory technology) and Snellen's visual acuity (VA). Descriptive statistics and mixed-effects multivariable linear regressions were evaluated. RESULTS: A total of 334 eyes (290 patients) with median age 61 years (range 21 to 88) had qCSF values as follows: area under the log contrast sensitivity function curve: 1.18; contrast acuity: 1.32; contrast sensitivity (CS) at 1 cycle per degree (cpd): 1.32; CS at 1.5 cpd: 1.37; CS at 3 cpd: 1.38; CS at 6 cpd: 1.20; CS at 12 cpd: 0.69; CS at 18 cpd: 0.22. Linear reductions in qCSF values per decade of age ranged from -0.02 to -0.07 vs 0.01 for visual acuity (VA). Age had a greater effect on the majority of qCSF values than VA (beta standardized regression coefficient ranged from -0.309 to -0.141 for qCSF values vs 0.177 for VA). CONCLUSIONS: We herein establish a normative database for qCSF and quantify the effect of age on qCSF values, adding evidence towards the validation of qCSF as a clinical endpoint. [Ophthalmic Surg Lasers Imaging Retina 2024;55:212-219.].


Assuntos
Envelhecimento , Sensibilidades de Contraste , Acuidade Visual , Humanos , Sensibilidades de Contraste/fisiologia , Adulto , Feminino , Masculino , Pessoa de Meia-Idade , Acuidade Visual/fisiologia , Idoso , Adulto Jovem , Idoso de 80 Anos ou mais , Envelhecimento/fisiologia , Voluntários Saudáveis , Valores de Referência , Bases de Dados Factuais
7.
JACC Heart Fail ; 12(7): 1179-1192, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38206234

RESUMO

BACKGROUND: Interventricular interactions may be responsible for the decline in ventricular performance observed in various disease states that primarily affect the contralateral ventricle. OBJECTIVES: This study sought to quantify the impact of such interactions on right ventricular (RV) size and function using clinically stable individuals with left ventricular assist devices (LVADs) as a model for assessing RV hemodynamics while LV loading conditions were acutely manipulated by changing device speed during hemodynamic optimization studies (ie, ramp tests). METHODS: The investigators recorded RV pressure-volume loops with a conductance catheter at various speeds during ramp tests in 20 clinically stable HeartMate3 recipients. RESULTS: With faster LVAD speeds and greater LV unloading, indexed RV end-diastolic volume increased (72.28 ± 15.07 mL at low speed vs 75.95 ± 16.90 at high speed; P = 0.04) whereas indexed end-systolic volumes remained neutral. This resulted in larger RV stroke volumes and shallower end-diastolic pressure-volume relationships. Concurrently, RV end-systolic pressure decreased (31.58 ± 9.75 mL at low speed vs 29.58 ± 9.41 mL at high speed; P = 0.02), but contractility, as measured by end-systolic elastance, did not change significantly. The reduction in RV end-systolic pressure was associated with a reduction in effective arterial elastance from 0.65 ± 0.43 mm Hg/mL at low speed to 0.54 ± 0.33 mm Hg/mL at high speed (P = 0.02). CONCLUSIONS: Interventricular interactions resulted in improved RV compliance, diminished afterload, and did not reduce RV contractility. These data challenge the prevailing view that interventricular interactions compromise RV function, which has important implications for the understanding of RV-LV interactions in various disease states, including post-LVAD RV dysfunction.


Assuntos
Insuficiência Cardíaca , Coração Auxiliar , Volume Sistólico , Função Ventricular Direita , Humanos , Masculino , Pessoa de Meia-Idade , Feminino , Função Ventricular Direita/fisiologia , Volume Sistólico/fisiologia , Insuficiência Cardíaca/fisiopatologia , Insuficiência Cardíaca/terapia , Ventrículos do Coração/fisiopatologia , Disfunção Ventricular Direita/fisiopatologia , Pressão Ventricular/fisiologia , Idoso , Adulto , Hemodinâmica/fisiologia
8.
Graefes Arch Clin Exp Ophthalmol ; 262(3): 813-822, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37955702

RESUMO

PURPOSE: The purpose of this study is to investigate test-retest reliability and agreement of the quantitative contrast sensitivity function test (qCSF) in the retina clinic. METHODS: A total of 121 right eyes of 121 patients were tested and consecutively re-tested with qCSF in the retina clinic. Outcomes included area under the logarithm of contrast sensitivity function curve (AULCSF), contrast acuity, and contrast sensitivity thresholds at 1-18 cycles per degree (cpd). Test-retest means were compared with paired t-test, variability was compared with the Brown-Forsythe test, and intraclass correlation coefficient (ICC) and Bland Altman plots evaluated reliability and agreement. RESULTS: Mean test-retest differences for all qCSF metrics ranged from 0.02 to 0.05 log units without statistically significant differences in variability. Standard deviations ranged from 0.08 to 0.14. Coefficients of repeatability ranged from 0.16 to 0.27 log units. ICC > 0.9 for all metrics except 1cpd (ICC = 0.84, all p < 0.001); AULCSF ICC = 0.971. CONCLUSION: qCSF-measured contrast sensitivity shows great test-retest repeatability and agreement in the retina clinic.


Assuntos
Sensibilidades de Contraste , Testes Visuais , Humanos , Reprodutibilidade dos Testes , Retina
9.
Clin Breast Cancer ; 24(2): e71-e79.e4, 2024 02.
Artigo em Inglês | MEDLINE | ID: mdl-37981475

RESUMO

BACKGROUND: Cardiovascular disease is the leading cause of noncancer mortality for breast cancer survivors. Data are limited regarding patient-level atherosclerotic cardiovascular disease (ASCVD) risk estimation and preventive medication use. This study aimed to characterize ASCVD risk and longitudinal preventive medication use for a cohort of patients with nonmetastatic breast cancer. PATIENTS AND METHODS: This retrospective cohort study included 326 patients at an academic medical center in Boston, Massachusetts diagnosed with nonmetastatic breast cancer or ductal carcinoma in situ from January 2009 through December 2015. Patient demographics, clinical characteristics, laboratory studies, medication exposure, and incident cardiovascular outcomes were collected. Estimated 10-year ASCVD risk was calculated for all patients from nonlaboratory clinical parameters. RESULTS: Median follow up time was 6.5 years (IQR 5.0, 8.1). At cancer diagnosis, 23 patients (7.1%) had established ASCVD. Among those without ASCVD, 10-year estimated ASCVD risk was ≥20% for 77 patients (25.4%) and 7.5% to <20% for 114 patients (37.6%). Two-hundred and sixteen patients (66.3%) had an indication for lipid-lowering therapy at cancer diagnosis, 123 of whom (57.0%) received a statin during the study. Among 100 patients with ASCVD or estimated 10-year ASCVD risk ≥20%, 92 (92.0%) received an antihypertensive medication during the study. Clinic blood pressure >140/90 mmHg was observed in 33.0% to 55.6% of these patients at each follow up assessment. CONCLUSION: A majority of patients in this breast cancer cohort had an elevated risk of ASCVD at the time of cancer diagnosis. Modifiable ASCVD risk factors were frequently untreated or uncontrolled in the years following cancer treatment.


Assuntos
Aterosclerose , Neoplasias da Mama , Doenças Cardiovasculares , Humanos , Feminino , Estudos Retrospectivos , Neoplasias da Mama/epidemiologia , Neoplasias da Mama/complicações , Aterosclerose/epidemiologia , Aterosclerose/tratamento farmacológico , Fatores de Risco , Medição de Risco
10.
Br J Ophthalmol ; 2023 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-37844999

RESUMO

BACKGROUND/AIMS: We sought to evaluate widefield swept-source optical coherence tomography angiography (WF SS-OCTA) among eyes with concomitant age-related macular degeneration (AMD) and diabetes mellitus or diabetic retinopathy (DM/DR). METHODS: This cross-sectional, comparative study consisted of three study groups: eyes with (1) AMD and DM/DR, (2) AMD alone and (3) DM/DR alone. WF SS-OCTA (3×3, 6×6 and 12×12 mm) images were captured. Vascular metrics included foveal avascular zone (FAZ), vessel density (VD) and vessel skeletonised density (VSD). Mixed-effects multivariable regression models adjusted for age were performed by cohort and subgroup based on AMD and DR stages. RESULTS: Our cohort included 287 eyes from 186 patients with an average age of 64±14.0 years old. Results revealed significantly reduced vascular metrics in concomitant AMD and DM/DR eyes (N=68) compared with AMD-only eyes (N=71) on all angiograms but not compared with DM/DR-only eyes (N=148). For example, when compared with AMD-only eyes, AMD and DM/DR eyes had significantly reduced VD (ß=-0.03, p=0.016) and VSD (ß=-1.09, p=0.022) on 12×12 mm angiograms, increased FAZ perimeter (ß=0.51, p=0.025) and FAZ area (ß=0.11, p=0.015) on 6×6 mm angiogram, and reductions in all VD and VSD metrics on 3×3 and 6×6 mm angiograms. However, only 3×3 mm angiogram FAZ metrics were significantly different when comparing DM/DR eyes with concomitant AMD and DM/DR eyes. CONCLUSION: WF SS-OCTA revealed significant reductions in retinal microvasculature metrics in AMD and DM/DR eyes compared with AMD-only eyes but not compared with DM/DR-only eyes.

11.
Future Cardiol ; 19(3): 127-135, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-37334764

RESUMO

Paclitaxel drug-coated balloons (DCBs) have been shown to improve patency and lower revascularization rates compared with plain old balloon angioplasty. DCBs continue to evolve by improving balloon-coating techniques that minimize the quantity of particles washed off into the bloodstream while maximizing drug retention and vascular-healing profile. Against this backdrop, it is clear that the future of antiproliferatives for the superficial femoral artery will focus on enhancements in device coating materials that will improve the efficiency of drug delivery. The Ranger DCB system recently gained US FDA approval for use. This review discusses the background of DCBs and how the Ranger DCB builds on these previous platforms based on experimental and clinical data.


Drug-coated balloons are medical devices used to open blocked arteries (a procedure called angioplasty) in patients who have atherosclerotic disease. The drug coating is provided to help keep the arteries open after treatment with the balloon. This is thought to occur through several mechanisms. In this review, we discuss recent advances in technology related to drug-coated balloons focusing on the recently introduced Ranger drug-coated Balloon.


Assuntos
Angioplastia com Balão , Antineoplásicos Fitogênicos , Paclitaxel , Doença Arterial Periférica , Sistemas de Liberação de Medicamentos , Humanos , Artéria Femoral , Materiais Revestidos Biocompatíveis , Paclitaxel/administração & dosagem , Paclitaxel/uso terapêutico , Antineoplásicos Fitogênicos/administração & dosagem , Antineoplásicos Fitogênicos/uso terapêutico , Doença Arterial Periférica/tratamento farmacológico
13.
J Phys Chem Lett ; 13(41): 9777-9785, 2022 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-36226837

RESUMO

Titanium (Ti), aluminum (Al), and boron (B) reactive mixed-metal nanopowders (Ti-Al-B RMNPs) represent attractive additives to hydrocarbon fuels such as exo-tetrahydrodicyclopentadiene (C10H16; JP-10) enhancing the limited volumetric energy densities of traditional hydrocarbons, but fundamental mechanisms and combustion stages in the oxidation have been obscure. This understanding is of vital significance in the development of next-generation propulsion systems and energy-generation technologies. Here, we expose distinct oxidation stages of single droplets of JP-10 doped with Ti-Al-B-RMNP exploiting innovative ultrasonic levitator technology coupled with time-resolved spectroscopic (UV-vis) and imaging diagnostics (optical and infrared). Two spatially and temporally distinct stages of combustion define a glow flame stage in which JP-10 and nanoparticles combust via a homogeneous gas phase (Al) and heterogeneous gas-surface oxidation (Ti, B) and a slower diffusion flame stage associated with the oxidation of JP-10. These findings enable the development of next-generation RMNP fuel additives with superior payload delivery capabilities.

14.
ACS Omega ; 7(28): 24705-24713, 2022 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-35874240

RESUMO

The electronic effects of supports on immobilized organometallic complexes impact their activity and lifetime, yet remain poorly understood. Here we describe a systematic study of the support effects experienced by an organometallic complex immobilized on doped hydrotalcite-like materials. To that end, we describe the synthesis and characterization of the first organometallic species immobilized on a palette of doped hydrotalcites via sulfonate linkers. The organometallic species consists of iridium N-heterocyclic carbene (NHC) carbonyl complex ([Na][Ir-(NHC-Ph-SO3)2(CO)2]), a highly active molecular catalyst for transfer hydrogenation of glycerol. The hydrotalcite supports are composed of Al, Mg, and a compatible transition-metal dopant (Fe, Cu, Ni, Zn). The materials were characterized extensively by STEM, XPS, TGA, PXRD, FT-IR, N2 desorption, ICP-AES, TPD, and microcalorimetry to probe the morphology and electronic properties of the support and elucidate structure-property relationships.

15.
Proc Natl Acad Sci U S A ; 119(5)2022 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-35091469

RESUMO

Sirt6 is a multifunctional enzyme that regulates diverse cellular processes such as metabolism, DNA repair, and aging. Overexpressing Sirt6 extends lifespan in mice, but the underlying cellular mechanisms are unclear. Drosophila melanogaster are an excellent model to study genetic regulation of lifespan; however, despite extensive study in mammals, very little is known about Sirt6 function in flies. Here, we characterized the Drosophila ortholog of Sirt6, dSirt6, and examined its role in regulating longevity; dSirt6 is a nuclear and chromatin-associated protein with NAD+-dependent histone deacetylase activity. dSirt6 overexpression (OE) in flies produces robust lifespan extension in both sexes, while reducing dSirt6 levels shortens lifespan. dSirt6 OE flies have normal food consumption and fertility but increased resistance to oxidative stress and reduced protein synthesis rates. Transcriptomic analyses reveal that dSirt6 OE reduces expression of genes involved in ribosome biogenesis, including many dMyc target genes. dSirt6 OE partially rescues many effects of dMyc OE, including increased nuclear size, up-regulation of ribosome biogenesis genes, and lifespan shortening. Last, dMyc haploinsufficiency does not convey additional lifespan extension to dSirt6 OE flies, suggesting dSirt6 OE is upstream of dMyc in regulating lifespan. Our results provide insight into the mechanisms by which Sirt6 OE leads to longer lifespan.


Assuntos
Longevidade/genética , Sirtuínas/metabolismo , Envelhecimento/fisiologia , Animais , Proteínas de Drosophila/metabolismo , Drosophila melanogaster/metabolismo , Feminino , Expressão Gênica/genética , Regulação da Expressão Gênica/genética , Haploinsuficiência/genética , Histona Desacetilases/economia , Histona Desacetilases/metabolismo , Masculino , Sirtuínas/genética
16.
EuroIntervention ; 17(13): 1053-1060, 2022 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-34483095

RESUMO

BACKGROUND: Moderate or worse paravalvular regurgitation (PVR) post transcatheter aortic valve replacement (TAVR) is associated with increased mortality. The mechanisms by which this occurs are not fully understood. AIMS: The aim of this study was to determine the mechanism by which PVR leads to worse outcomes. METHODS: A total of 1,974 intermediate-risk patients who received TAVR in the PARTNER 2 trial and registries were grouped by PVR severity. Clinical and echocardiographic outcomes were compared. RESULTS: Overall 1,176 (60%) patients had none/trace, 680 (34%) had mild, and 118 (6%) had ≥moderate PVR. At two years, ≥moderate PVR patients had increased risks of all-cause (HR 2.33 [1.41-3.85], p-value=0.001) and cardiovascular death (HR 3.30 [1.74-6.28], p-value <0.001), rehospitalisation (HR 2.68 [1.57-4.58], p-value <0.001), and reintervention (HR 14.72 [3.13-69.32], p-value <0.001). Moderate or worse PVR was associated with larger increases in left ventricular (LV) end-diastolic and systolic dimensions and volumes, LV mass indices, and reductions in LV ejection fractions (LVEFs) from 30 days to two years. Mild PVR was not associated with worse outcomes. Adjusting for LV dimensions and LVEF from the one-year echocardiogram, patients with ≥moderate PVR still had an increased risk of all-cause death or rehospitalisation at two years (HR 2.84 [1.25-5.78], p-value=0.009). CONCLUSIONS: Moderate or worse PVR, but not mild PVR, is associated with an increased risk of all-cause and cardiovascular death, rehospitalisation, and reintervention at two years. Moderate or worse PVR is also associated with adverse LV remodelling, which partially mediates how ≥moderate PVR leads to worse outcomes. These results provide dual insights on the deleterious impact of ≥moderate PVR and the contributing mechanisms of poor clinical outcomes.


Assuntos
Insuficiência da Valva Aórtica , Estenose da Valva Aórtica , Substituição da Valva Aórtica Transcateter , Valva Aórtica/diagnóstico por imagem , Valva Aórtica/cirurgia , Insuficiência da Valva Aórtica/diagnóstico por imagem , Insuficiência da Valva Aórtica/etiologia , Insuficiência da Valva Aórtica/cirurgia , Estenose da Valva Aórtica/cirurgia , Humanos , Fatores de Risco , Índice de Gravidade de Doença , Substituição da Valva Aórtica Transcateter/efeitos adversos , Resultado do Tratamento
17.
J Phys Chem A ; 126(1): 125-144, 2022 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-34935392

RESUMO

We report the results on the combustion of single, levitated droplets of exo-tetrahydrodicyclopentadiene (JP-10) doped with titanium-aluminum-boron (Ti-Al-B) reactive metal nanopowders (RMNPs) in an oxygen (60%)-argon (40%) atmosphere by exploiting an ultrasonic levitator with droplets ignited by a carbon dioxide laser. Ultraviolet-visible (UV-vis) emission spectroscopy revealed the presence of gas-phase aluminum (Al) and titanium (Ti) atoms. These atoms can be oxidized in the gas phase by molecular oxygen to form spectroscopically detected aluminum monoxide (AlO) and titanium monoxide (TiO) transients. Analysis of the optical ignition videos supports that the nanoparticles are ignited before JP-10. The detection of boron monoxide (BO) further proposes an active surface chemistry through the oxidation of the RMNPs and the release of at least BO into the gas phase. The oxidation of gas-phase BO by molecular oxygen to boron dioxide (BO2) plus atomic oxygen might operate in the gas phase, although the involvement of surface oxidation processes of RMNPs to BO2 cannot be discounted. The UV-vis emission spectra also revealed the key reactive intermediates (OH, CH, C2, and HCO) of the oxidation of JP-10. Electronic structure calculations reveal that the presence of reactive radicals has a profound impact on the oxidation of JP-10. Although titanium monoxide (TiO) reacts to produce titanium dioxide (TiO2), it does not engage in an active JP-10 chemistry as all abstraction pathways are endoergic by more than 217 kJ mol-1. This is similar for atomic aluminum and titanium, whose hydrogen abstraction reactions from JP-10 were revealed to be endoergic by at least 77 kJ mol-1. Therefore, aluminum and titanium react preferentially with molecular oxygen to produce their monoxides. However, the formation of BO, AlO, and BO2 supplies a pool of highly reactive radicals, which can abstract hydrogen from JP-10 via transition states ranging from only 1 to 5 kJ mol-1 above the separated reactants, forming JP-10 radicals along with the hydrogen abstraction products (boron hydride oxide, aluminum monohydroxide, and metaboric acid) in the overall exoergic reactions. These abstraction barriers are well below the barriers of abstractions for ground-state atomic oxygen and molecular oxygen. In this sense, gas-phase BO, AlO, and BO2 catalyze the oxidation of gas-phase JP-10 via hydrogen abstraction, forming highly reactive JP-10 radicals. Overall, the addition of RMNPs to JP-10 not only provides a higher energy density fuel but is also expected to lead to shorter ignition delays compared to pure JP-10 due to the highly reactive pool of radicals (BO, AlO, and BO2) formed in the initial stage of the oxidation process.

18.
JACC Case Rep ; 4(24): 101667, 2022 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-36684029

RESUMO

Intraprocedural embolization has been described as a potential complication of catheter thrombectomy for acute pulmonary embolism and may be under-recognized. We describe 2 case examples of "Lollipopping" during thrombectomy, which may be a mechanism of intraprocedural embolization and describe our treatment approach. (Level of Difficulty: Advanced.).

19.
Circ Cardiovasc Interv ; 14(11): e009374, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34784236

RESUMO

BACKGROUND: Women have a higher rate of adverse events after mitral valve surgery. We sought to evaluate whether outcomes after transcatheter edge-to-edge repair intervention by sex have similar trends to mitral valve surgery. METHODS: The primary outcome was 1-year major adverse events defined as a composite of all-cause mortality, stroke, and any bleeding in the overall study cohort. Patients who underwent transcatheter edge-to-edge repair for mitral regurgitation with the MitraClip system in the Society of Thoracic Surgery/American College of Cardiology Transcatheter Valve Therapy registry were evaluated. Linked administrative claims from the Centers for Medicare and Medicaid Services were used to evaluate 1-year clinical outcomes. Associations between sex and outcomes were evaluated using a multivariable logistic regression model for in-hospital outcomes and Cox model for 1-year outcomes. RESULTS: From November 2013 to March 2017, 5295 patients, 47.6% (n=2523) of whom were female, underwent transcatheter edge-to-edge repair. Females were less likely to have >1 clip implanted (P<0.001) and had a lower adjusted odds ratio of device success (adjusted odds ratio, 0.78 [95% CI, 0.67-0.90]), driven by lower odds of residual mitral gradient <5 mm Hg (adjusted odds ratio, 0.54 [CI, 0.46-0.63]) when compared with males. At 1-year follow-up, the primary outcome did not differ by sex. Female sex was associated with lower adjusted 1-year risk of all-cause mortality (adjusted hazard ratio, 0.80 [CI, 0.68-0.94]), but the adjusted 1-year risk of stroke and any bleeding did not differ by sex. CONCLUSIONS: No difference in composite outcome of all-cause mortality, stroke, and any bleeding was observed between females and males. Adjusted 1-year all-cause mortality was lower in females compared with males.


Assuntos
Implante de Prótese de Valva Cardíaca , Insuficiência da Valva Mitral , Idoso , Feminino , Implante de Prótese de Valva Cardíaca/efeitos adversos , Humanos , Masculino , Medicare , Insuficiência da Valva Mitral/diagnóstico por imagem , Insuficiência da Valva Mitral/epidemiologia , Insuficiência da Valva Mitral/cirurgia , Sistema de Registros , Resultado do Tratamento , Estados Unidos/epidemiologia
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