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1.
Lancet ; 403(10436): 1543-1553, 2024 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-38604209

RESUMO

BACKGROUND: The coronary sinus reducer (CSR) is proposed to reduce angina in patients with stable coronary artery disease by improving myocardial perfusion. We aimed to measure its efficacy, compared with placebo, on myocardial ischaemia reduction and symptom improvement. METHODS: ORBITA-COSMIC was a double-blind, randomised, placebo-controlled trial conducted at six UK hospitals. Patients aged 18 years or older with angina, stable coronary artery disease, ischaemia, and no further options for treatment were eligible. All patients completed a quantitative adenosine-stress perfusion cardiac magnetic resonance scan, symptom and quality-of-life questionnaires, and a treadmill exercise test before entering a 2-week symptom assessment phase, in which patients reported their angina symptoms using a smartphone application (ORBITA-app). Patients were randomly assigned (1:1) to receive either CSR or placebo. Both participants and investigators were masked to study assignment. After the CSR implantation or placebo procedure, patients entered a 6-month blinded follow-up phase in which they reported their daily symptoms in the ORBITA-app. At 6 months, all assessments were repeated. The primary outcome was myocardial blood flow in segments designated ischaemic at enrolment during the adenosine-stress perfusion cardiac magnetic resonance scan. The primary symptom outcome was the number of daily angina episodes. Analysis was done by intention-to-treat and followed Bayesian methodology. The study is registered with ClinicalTrials.gov, NCT04892537, and completed. FINDINGS: Between May 26, 2021, and June 28, 2023, 61 patients were enrolled, of whom 51 (44 [86%] male; seven [14%] female) were randomly assigned to either the CSR group (n=25) or the placebo group (n=26). Of these, 50 patients were included in the intention-to-treat analysis (24 in the CSR group and 26 in the placebo group). 454 (57%) of 800 imaged cardiac segments were ischaemic at enrolment, with a median stress myocardial blood flow of 1·08 mL/min per g (IQR 0·77-1·41). Myocardial blood flow in ischaemic segments did not improve with CSR compared with placebo (difference 0·06 mL/min per g [95% CrI -0·09 to 0·20]; Pr(Benefit)=78·8%). The number of daily angina episodes was reduced with CSR compared with placebo (OR 1·40 [95% CrI 1·08 to 1·83]; Pr(Benefit)=99·4%). There were two CSR embolisation events in the CSR group, and no acute coronary syndrome events or deaths in either group. INTERPRETATION: ORBITA-COSMIC found no evidence that the CSR improved transmural myocardial perfusion, but the CSR did improve angina compared with placebo. These findings provide evidence for the use of CSR as a further antianginal option for patients with stable coronary artery disease. FUNDING: Medical Research Council, Imperial College Healthcare Charity, National Institute for Health and Care Research Imperial Biomedical Research Centre, St Mary's Coronary Flow Trust, British Heart Foundation.


Assuntos
Angina Estável , Doença da Artéria Coronariana , Seio Coronário , Intervenção Coronária Percutânea , Humanos , Masculino , Feminino , Doença da Artéria Coronariana/terapia , Angina Estável/tratamento farmacológico , Seio Coronário/diagnóstico por imagem , Teorema de Bayes , Resultado do Tratamento , Intervenção Coronária Percutânea/efeitos adversos , Método Duplo-Cego , Isquemia , Adenosina
2.
BMC Plant Biol ; 24(1): 624, 2024 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-38951758

RESUMO

Drought poses significant risks to maize cultivation by impairing plant growth, water uptake and yield; nano priming offers a promising avenue to mitigate these effects by enhancing plant water relations, stress tolerance and overall productivity. In the current experiment, we tested a hypothesis that seed priming with iron oxide nanoparticles (n-Fe2O3) can improve maize performance under water stress by improving its growth, water relations, yield and biochemical attributes. The experiment was conducted on a one main plot bisected into two subplots corresponding to the water and drought environments. Within each subplot, maize plants were raised from n-Fe2O3 primed seeds corresponding to 0 mg. L- 1 (as control treatment), 25, 50, 75, and 100 mg. L- 1 (as trial treatments). Seed priming with n-Fe2O3 at a concentration of 75 mg. L- 1 improved the leaf relative water content, water potential, photosynthetic water use efficiency, and leaf intrinsic water use efficiency of maize plants by 13%, 44%, 64% and 17%, respectively compared to control under drought stress. The same treatments improved plant biochemical attributes such as total chlorophyll content, total flavonoids and ascorbic acid by 37%, 22%, and 36%, respectively. Seed priming with n-Fe2O3 accelerated the functioning of antioxidant enzymes such as SOD and POD and depressed the levels of leaf malondialdehyde and hydrogen peroxide significantly. Seed priming with n-Fe2O3 at a concentration of 75 mg. L- 1 improved cob length, number of kernel rows per cob, and 100 kernel weight by 59%, 27% and 33%, respectively, under drought stress. Seed priming with n-Fe2O3 can be used to increase maize production under limited water scenarios.


Assuntos
Desidratação , Sementes , Água , Zea mays , Zea mays/efeitos dos fármacos , Zea mays/fisiologia , Zea mays/crescimento & desenvolvimento , Zea mays/metabolismo , Sementes/efeitos dos fármacos , Sementes/crescimento & desenvolvimento , Sementes/fisiologia , Água/metabolismo , Secas , Fotossíntese/efeitos dos fármacos , Compostos Férricos , Clorofila/metabolismo , Folhas de Planta/efeitos dos fármacos , Folhas de Planta/fisiologia
3.
J Magn Reson Imaging ; 58(6): 1797-1812, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-36929232

RESUMO

BACKGROUND: Biological heart age estimation can provide insights into cardiac aging. However, existing studies do not consider differential aging across cardiac regions. PURPOSE: To estimate biological age of the left ventricle (LV), right ventricle (RV), myocardium, left atrium, and right atrium using magnetic resonance imaging radiomics phenotypes and to investigate determinants of aging by cardiac region. STUDY TYPE: Cross-sectional. POPULATION: A total of 18,117 healthy UK Biobank participants including 8338 men (mean age = 64.2 ± 7.5) and 9779 women (mean age = 63.0 ± 7.4). FIELD STRENGTH/SEQUENCE: A 1.5 T/balanced steady-state free precession. ASSESSMENT: An automated algorithm was used to segment the five cardiac regions, from which radiomic features were extracted. Bayesian ridge regression was used to estimate biological age of each cardiac region with radiomics features as predictors and chronological age as the output. The "age gap" was the difference between biological and chronological age. Linear regression was used to calculate associations of age gap from each cardiac region with socioeconomic, lifestyle, body composition, blood pressure and arterial stiffness, blood biomarkers, mental well-being, multiorgan health, and sex hormone exposures (n = 49). STATISTICAL TEST: Multiple testing correction with false discovery method (threshold = 5%). RESULTS: The largest model error was with RV and the smallest with LV age (mean absolute error in men: 5.26 vs. 4.96 years). There were 172 statistically significant age gap associations. Greater visceral adiposity was the strongest correlate of larger age gaps, for example, myocardial age gap in women (Beta = 0.85, P = 1.69 × 10-26 ). Poor mental health associated with large age gaps, for example, "disinterested" episodes and myocardial age gap in men (Beta = 0.25, P = 0.001), as did a history of dental problems (eg LV in men Beta = 0.19, P = 0.02). Higher bone mineral density was the strongest associate of smaller age gaps, for example, myocardial age gap in men (Beta = -1.52, P = 7.44 × 10-6 ). DATA CONCLUSION: This work demonstrates image-based heart age estimation as a novel method for understanding cardiac aging. EVIDENCE LEVEL: 1. TECHNICAL EFFICACY: Stage 1.


Assuntos
Ventrículos do Coração , Coração , Masculino , Humanos , Feminino , Pessoa de Meia-Idade , Idoso , Estudos Transversais , Teorema de Bayes , Coração/diagnóstico por imagem , Ventrículos do Coração/diagnóstico por imagem , Envelhecimento/fisiologia , Imageamento por Ressonância Magnética , Função Ventricular Esquerda/fisiologia
4.
Eur Radiol ; 2023 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-37987834

RESUMO

OBJECTIVES: To use pericardial adipose tissue (PAT) radiomics phenotyping to differentiate existing and predict future heart failure (HF) cases in the UK Biobank. METHODS: PAT segmentations were derived from cardiovascular magnetic resonance (CMR) studies using an automated quality-controlled model to define the region-of-interest for radiomics analysis. Prevalent (present at time of imaging) and incident (first occurrence after imaging) HF were ascertained using health record linkage. We created balanced cohorts of non-HF individuals for comparison. PyRadiomics was utilised to extract 104 radiomics features, of which 28 were chosen after excluding highly correlated ones (0.8). These features, plus sex and age, served as predictors in binary classification models trained separately to detect (1) prevalent and (2) incident HF. We tested seven modeling methods using tenfold nested cross-validation and examined feature importance with explainability methods. RESULTS: We studied 1204 participants in total, 297 participants with prevalent (60 ± 7 years, 21% female) and 305 with incident (61 ± 6 years, 32% female) HF, and an equal number of non-HF comparators. We achieved good discriminative performance for both prevalent (voting classifier; AUC: 0.76; F1 score: 0.70) and incident (light gradient boosting machine: AUC: 0.74; F1 score: 0.68) HF. Our radiomics models showed marginally better performance compared to PAT area alone. Increased PAT size (maximum 2D diameter in a given column or slice) and texture heterogeneity (sum entropy) were important features for prevalent and incident HF classification models. CONCLUSIONS: The amount and character of PAT discriminate individuals with prevalent HF and predict incidence of future HF. CLINICAL RELEVANCE STATEMENT: This study presents an innovative application of pericardial adipose tissue (PAT) radiomics phenotyping as a predictive tool for heart failure (HF), a major public health concern. By leveraging advanced machine learning methods, the research uncovers that the quantity and characteristics of PAT can be used to identify existing cases of HF and predict future occurrences. The enhanced performance of these radiomics models over PAT area alone supports the potential for better personalised care through earlier detection and prevention of HF. KEY POINTS: •PAT radiomics applied to CMR was used for the first time to derive binary machine learning classifiers to develop models for discrimination of prevalence and prediction of incident heart failure. •Models using PAT area provided acceptable discrimination between cases of prevalent or incident heart failure and comparator groups. •An increased PAT volume (increased diameter using shape features) and greater texture heterogeneity captured by radiomics texture features (increased sum entropy) can be used as an additional classifier marker for heart failure.

5.
Hepatobiliary Pancreat Dis Int ; 22(6): 554-569, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36973111

RESUMO

BACKGROUND: Post-hepatectomy liver failure (PHLF) is a leading cause of postoperative mortality after liver surgery. Due to its significant impact, it is imperative to understand the risk stratification and preventative strategies for PHLF. The main objective of this review is to highlight the role of these strategies in a timeline centered way around curative resection. DATA SOURCES: This review includes studies on both humans and animals, where they addressed PHLF. A literature search was conducted across the Cochrane Library, Embase, MEDLINE/PubMed, and Web of Knowledge electronic databases for English language studies published between July 1997 and June 2020. Studies presented in other languages were equally considered. The quality of included publications was assessed using Downs and Black's checklist. The results were presented in qualitative summaries owing to the lack of studies qualifying for quantitative analysis. RESULTS: This systematic review with 245 studies, provides insight into the current prediction, prevention, diagnosis, and management options for PHLF. This review highlighted that liver volume manipulation is the most frequently studied preventive measure against PHLF in clinical practice, with modest improvement in the treatment strategies over the past decade. CONCLUSIONS: Remnant liver volume manipulation is the most consistent preventive measure against PHLF.


Assuntos
Falência Hepática , Neoplasias Hepáticas , Humanos , Hepatectomia/efeitos adversos , Neoplasias Hepáticas/cirurgia , Falência Hepática/diagnóstico , Falência Hepática/etiologia , Falência Hepática/prevenção & controle , Testes de Função Hepática , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/cirurgia , Estudos Retrospectivos
6.
J Magn Reson Imaging ; 55(1): 154-163, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34189804

RESUMO

BACKGROUND: The mechanisms driving primary progressive and relapsing-remitting multiple sclerosis (PPMS/RRMS) phenotypes are unknown. Magnetic resonance imaging (MRI) studies support the involvement of gray matter (GM) in the degeneration, highlighting its damage as an early feature of both phenotypes. However, the role of GM microstructure is unclear, calling for new methods for its decryption. PURPOSE: To investigate the morphometric and microstructural GM differences between PPMS and RRMS to characterize GM tissue degeneration using MRI. STUDY TYPE: Prospective cross-sectional study. SUBJECTS: Forty-five PPMS (26 females) and 45 RRMS (32 females) patients. FIELD STRENGTH/SEQUENCE: 3T scanner. Three-dimensional (3D) fast field echo T1-weighted (T1-w), 3D turbo spin echo (TSE) T2-w, 3D TSE fluid-attenuated inversion recovery, and spin echo-echo planar imaging diffusion MRI (dMRI). ASSESSMENT: T1-w and dMRI data were employed for providing information about morphometric and microstructural features, respectively. For dMRI, both diffusion tensor imaging and 3D simple harmonics oscillator based reconstruction and estimation models were used for feature extraction from a predefined set of regions. A support vector machine (SVM) was used to perform patients' classification relying on all these measures. STATISTICAL TESTS: Differences between MS phenotypes were investigated using the analysis of covariance and statistical tests (P < 0.05 was considered statistically significant). RESULTS: All the dMRI indices showed significant microstructural alterations between the considered MS phenotypes, for example, the mode and the median of the return to the plane probability in the hippocampus. Conversely, thalamic volume was the only morphometric feature significantly different between the two MS groups. Ten of the 12 features retained by the selection process as discriminative across the two MS groups regarded the hippocampus. The SVM classifier using these selected features reached an accuracy of 70% and a precision of 69%. DATA CONCLUSION: We provided evidence in support of the ability of dMRI to discriminate between PPMS and RRMS, as well as highlight the central role of the hippocampus. LEVEL OF EVIDENCE: 2 TECHNICAL EFFICACY STAGE: 3.


Assuntos
Esclerose Múltipla Recidivante-Remitente , Esclerose Múltipla , Estudos Transversais , Imagem de Tensor de Difusão , Humanos , Imageamento por Ressonância Magnética , Esclerose Múltipla Recidivante-Remitente/diagnóstico por imagem , Fenótipo , Estudos Prospectivos
7.
Pancreatology ; 22(7): 1041-1045, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35931645

RESUMO

BACKGROUND: Exocrine pancreatic insufficiency (EPI) is a known complication of upper gastrointestinal surgery and has recently been associated with bariatric surgery. Our objectives were to determine the incidence of EPI in patients who underwent bariatric surgery and to identify the type of bariatric procedure most associated with EPI. METHODS: This retrospective cohort analysis included patients age ≥18 years who underwent bariatric surgery at Mayo Clinic between 2010 and 2020. Patients with a history of other gastrointestinal or hepatobiliary resection, revision of bariatric surgery, EPI prior to surgery, and surgery greater than >10 years earlier were excluded from the study. Characteristics were compared between two groups based on type of bariatric surgery including Roux-en-Y gastric bypass (RYGB) or gastric sleeve (GS). Characteristics were also analyzed between patients with RYGB who developed post-operative steatorrhea and those who did not. RESULTS: Of 150 patients, 126 underwent RYGB while 24 patients had GS. Thirty-one (20.6%) patients developed post-operative steatorrhea and 14 (9.3%) were diagnosed with EPI. Mean pancreatic elastase level was 287 ± 156 mcg/g and fecal fat level 31 ± 22 g/d. There was a significantly higher proportion of post-operative steatorrhea in patients who underwent RYGB compared to gastric sleeve surgery (p = 0.029). CONCLUSION: The incidence of EPI after bariatric surgery in our cohort was 9.3%. Overall, patients who underwent RYGB had higher rates of EPI (10.3%) than those who had GS (4.2%). Clinicians should be aware of EPI as a cause for steatorrhea in patients who underwent bariatric surgery and consider treatment with enzyme replacement therapy.


Assuntos
Cirurgia Bariátrica , Insuficiência Pancreática Exócrina , Obesidade Mórbida , Esteatorreia , Humanos , Adolescente , Obesidade Mórbida/cirurgia , Obesidade Mórbida/complicações , Estudos Retrospectivos , Esteatorreia/epidemiologia , Esteatorreia/etiologia , Cirurgia Bariátrica/efeitos adversos , Cirurgia Bariátrica/métodos , Insuficiência Pancreática Exócrina/epidemiologia , Insuficiência Pancreática Exócrina/etiologia , Resultado do Tratamento
8.
Scand J Gastroenterol ; 57(3): 298-304, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34859738

RESUMO

OBJECTIVES: Patients with microscopic colitis may have subtle macroscopic findings on colonoscopy such as erythema, edema, or altered vascular pattern; however, radiographic abnormalities on cross-sectional imaging have not been investigated. We aimed at identifying the abdominopelvic radiographic abnormalities in patients with microscopic colitis, as well as possible correlation with endoscopic findings and the need for extended duration of treatment. MATERIALS AND METHODS: This was a retrospective study of patients with biopsy-proven microscopic colitis at two tertiary centers between 1 January 2010 and 30 April 2020. Patients underwent computed tomography scan or magnetic resonance imaging within 30 days of a diagnostic flexible sigmoidoscopy or colonoscopy. Patients with colon ischemia and other causes of colitis were excluded. Radiographic abnormalities from imaging reports included bowel wall thickening, mucosal hyperenhancement and mesenteric fat stranding. Univariate and multivariable logistic regression models were used to identify predictors of radiographic abnormalities. RESULTS: 498 patients with microscopic colitis underwent abdominopelvic cross-sectional imaging within 30 days of flexible sigmoidoscopy/colonoscopy. Lymphocytic colitis was diagnosed in 54.6% of patients, and collagenous colitis in 45.4%. Endoscopic and radiographic abnormalities were identified in 16.1% and 12.4% of patients, respectively. Radiographic abnormalities were associated with the need for budesonide therapy (p = .029) and budesonide therapy long-term (p = .0028). Budesonide therapy long-term (p = .047) was associated with radiographic abnormalities in multivariate analysis. CONCLUSIONS: Radiographic abnormalities may be present on abdominopelvic cross-sectional imaging in a minority of patients with biopsy-proven microscopic colitis, suggesting cross-sectional imaging has low clinical value in the evaluation and treatment of this disease.


Assuntos
Colite Colagenosa , Colite Linfocítica , Colite Microscópica , Biópsia , Colite Colagenosa/patologia , Colite Linfocítica/patologia , Colite Microscópica/diagnóstico , Colo/patologia , Colonoscopia/métodos , Humanos , Estudos Retrospectivos , Sigmoidoscopia
9.
Small ; 17(51): e2102876, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34605152

RESUMO

Commercial implantable continuous glucose monitoring devices are invasive and discomfort. Here, a minimally-invasive glucose detection system is developed to provide quantitative glucose measurements continually based on bifocal contact lenses. A glucose-sensitive phenylboronic acid derivative is immobilized in a hydrogel matrix and the surface of the hydrogel is imprinted with a Fresnel lens. The glucose-responsive hydrogel is attached to a commercial soft contact lens to be transformed into a bifocal contact lens. The contact lens showed bifocal lengths; far-field focal length originated from the contact lens' curvature, and near-field focal length resulting from the Fresnel lens. When tear glucose increased, the refractive index and groove depth of the Fresnel lens changed, shifting the near-field focal length and the light focusing efficiency. The recorded optical signals are detected at an identical distance far from the contact lens change. The bifocal contact lens allowed for detecting the tear glucose concentration within the physiological range of healthy individuals and diabetics (0.0-3.3 mm). The contact lens rapidly responded to glucose concentration changes and reached 90% of equilibrium within 40 min. The bifocal contact lens is a wearable diagnostic platform for continual biomarker detection at point-of-care settings.


Assuntos
Lentes de Contato Hidrofílicas , Dispositivos Eletrônicos Vestíveis , Glicemia , Automonitorização da Glicemia , Glucose , Humanos , Smartphone , Acuidade Visual
10.
Paediatr Anaesth ; 29(2): 169-174, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30521078

RESUMO

BACKGROUND: Surgical wound infiltration with local anesthetics is common as part of multimodal analgesia and enhanced recovery pathways in pediatric surgical patients. Liposomal bupivacaine can provide up to 92 hours of pain relief, and was approved by the U.S Food and Drug Administration for local infiltration in adults. It is also commonly used by pediatric surgeons, but its safety profile in this age group has not been described. AIMS: The aim of this study was to describe the incidence of local anesthetic systemic toxicity syndrome in pediatric surgical patients receiving liposomal bupivacaine compared to plain bupivacaine for surgical wound infiltration. METHODS: We conducted a retrospective, single center, assessor blinded cohort study of pediatric surgical inpatients having open or laparoscopic surgery in the Cleveland Clinic between 2013 and 2017 and receiving wound infiltration with local anesthetics. We compared the incidence of local anesthetic systemic toxicity among those who received any dose of liposomal bupivacaine and those who received plain bupivacaine. Groups were matched 1:2 according to procedure type, age, and physical status score. Local anesthetic systemic toxicity was primarily defined as at least two signs or symptoms possibly related to anesthetic toxicity, as judged by two independent adjudicators blinded to the type of local anesthetic. A sensitivity analysis compared the incidence of a single sign/symptom possibly related to anesthetic toxicity. RESULTS: A total of 924 surgical cases were included in the final analysis (356 liposomal bupivacaine and 568 plain bupivacaine cases). The primary outcome did not occur in any patient. The sensitivity analysis found three cases in the liposomal bupivacaine group and two cases in the plain bupivacaine group having a single sign/symptom possibly related to local anesthetic administration (relative risk 2.4, 95% CI 0.4-14.0, P = 0.38). CONCLUSION: In a cohort of pediatric surgical patients receiving wound infiltration with either plain or liposomal bupivacaine, we identified no cases of local anesthetic systemic toxicity syndrome, and only few patients with any sign or symptom that could potentially be related to local anesthetic toxicity.


Assuntos
Anestésicos Locais/administração & dosagem , Anestésicos Locais/efeitos adversos , Bupivacaína/administração & dosagem , Bupivacaína/efeitos adversos , Dor Pós-Operatória/tratamento farmacológico , Adolescente , Anestesia Local/efeitos adversos , Anestesia Local/métodos , Criança , Pré-Escolar , Estudos de Coortes , Feminino , Humanos , Incidência , Lactente , Laparoscopia , Lipossomos/administração & dosagem , Masculino , Manejo da Dor/métodos , Estudos Retrospectivos , Suspensões/administração & dosagem
11.
J Am Heart Assoc ; 13(3): e032708, 2024 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-38293941

RESUMO

BACKGROUND: Existing research demonstrates the association of shorter leukocyte telomere length with increased risk of age-related health outcomes including cardiovascular diseases. However, the direct causality of these relationships has not been definitively established. Cardiovascular aging at an organ level may be captured using image-derived phenotypes of cardiac anatomy and function. METHODS AND RESULTS: In the current study, we use 2-sample Mendelian randomization to assess the causal link between leukocyte telomere length and 54 cardiac magnetic resonance imaging measures representing structure and function across the 4 cardiac chambers. Genetically predicted shorter leukocyte telomere length was causally linked to smaller ventricular cavity sizes including left ventricular end-systolic volume, left ventricular end-diastolic volume, lower left ventricular mass, and pulmonary artery. The association with left ventricular mass (ß =0.217, Pfalse discovery rate=0.016) remained significant after multiple testing adjustment, whereas other associations were attenuated. CONCLUSIONS: Our findings support a causal role for shorter leukocyte telomere length and faster cardiac aging, with the most prominent relationship with left ventricular mass.


Assuntos
Coração , Análise da Randomização Mendeliana , Análise da Randomização Mendeliana/métodos , Leucócitos , Telômero/genética , Estudo de Associação Genômica Ampla
12.
Artigo em Inglês | MEDLINE | ID: mdl-38696291

RESUMO

Explainable Artificial Intelligence (XAI) provides tools to help understanding how AI models work and reach a particular decision or outcome. It helps to increase the interpretability of models and makes them more trustworthy and transparent. In this context, many XAI methods have been proposed to make black-box and complex models more digestible from a human perspective. However, one of the main issues that XAI methods have to face especially when dealing with a high number of features is the presence of multicollinearity, which casts shadows on the robustness of the XAI outcomes, such as the ranking of informative features. Most of the current XAI methods either do not consider the collinearity or assume the features are independent which, in general, is not necessarily true. Here, we propose a simple, yet useful, proxy that modifies the outcome of any XAI feature ranking method allowing to account for the dependency among the features, and to reveal their impact on the outcome. The proposed method was applied to SHAP, as an example of XAI method which assume that the features are independent. For this purpose, several models were exploited for a well-known classification task (males versus females) using nine cardiac phenotypes extracted from cardiac magnetic resonance imaging as features. Principal component analysis and biological plausibility were employed to validate the proposed method. Our results showed that the proposed proxy could lead to a more robust list of informative features compared to the original SHAP in presence of collinearity.

13.
ACS Appl Nano Mater ; 7(6): 5956-5966, 2024 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-38544505

RESUMO

Constant exposure to blue light emanating from screens, lamps, digital devices, or other artificial sources at night can suppress melatonin secretion, potentially compromising both sleep quality and overall health. Daytime exposure to elevated levels of blue light can also lead to permanent damage to the eyes. Here, we have developed blue light protective plasmonic contact lenses (PCLs) to mitigate blue light exposure. Crafted from poly(hydroxyethyl methacrylate) (pHEMA) and infused with silver nanoparticles, these contact lenses serve as a protective barrier to filter blue light. Leveraging the plasmonic properties of silver nanoparticles, the lenses effectively filtered out the undesirable blue light (400-510 nm), demonstrating substantial protection (22-71%) while maintaining high transparency (80-96%) for the desirable light (511-780 nm). The maximum protection level reaches a peak of 79% at 455 nm, aligned with the emission peak for the blue light sourced from LEDs in consumer displays. The presence of silver nanoparticles was found to have an insignificant impact on the water content of the developed contact lenses. The lenses maintained high water retention levels within the range of 50-70 wt %, comparable to commercial contact lenses. The optical performance of the developed lenses remains unaffected in both artificial tears and contact lens storage solution over a month with no detected leakage of the nanoparticles. Additionally, the MTT assay confirmed that the lenses were biocompatible and noncytotoxic, maintaining cell viability at over 85% after 24 h of incubation. These lenses could be a potential solution to protect against the most intense wavelengths emitted by consumer displays and offer a remedy to counteract the deleterious effects of prolonged blue light exposure.

14.
JACC Cardiovasc Imaging ; 17(5): 533-551, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38597854

RESUMO

Population aging is one of the most important demographic transformations of our time. Increasing the "health span"-the proportion of life spent in good health-is a global priority. Biological aging comprises molecular and cellular modifications over many years, which culminate in gradual physiological decline across multiple organ systems and predispose to age-related illnesses. Cardiovascular disease is a major cause of ill health and premature death in older people. The rate at which biological aging occurs varies across individuals of the same age and is influenced by a wide range of genetic and environmental exposures. The authors review the hallmarks of biological cardiovascular aging and their capture using imaging and other noninvasive techniques and examine how this information may be used to understand aging trajectories, with the aim of guiding individual- and population-level interventions to promote healthy aging.


Assuntos
Envelhecimento , Doenças Cardiovasculares , Sistema Cardiovascular , Valor Preditivo dos Testes , Humanos , Envelhecimento/metabolismo , Doenças Cardiovasculares/fisiopatologia , Doenças Cardiovasculares/diagnóstico por imagem , Doenças Cardiovasculares/metabolismo , Sistema Cardiovascular/fisiopatologia , Sistema Cardiovascular/metabolismo , Fatores Etários , Idoso , Envelhecimento Saudável , Prognóstico , Pessoa de Meia-Idade , Feminino , Masculino , Idoso de 80 Anos ou mais , Animais , Senescência Celular
15.
JBMR Plus ; 8(6): ziae058, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38784722

RESUMO

This study examined the association of estimated heel bone mineral density (eBMD, derived from quantitative ultrasound) with: (1) prevalent and incident cardiovascular diseases (CVDs: ischemic heart disease (IHD), myocardial infarction (MI), heart failure (HF), non-ischemic cardiomyopathy (NICM), arrhythmia), (2) mortality (all-cause, CVD, IHD), and (3) cardiovascular magnetic resonance (CMR) measures of left ventricular and atrial structure and function and aortic distensibility, in the UK Biobank. Clinical outcomes were ascertained using health record linkage over 12.3 yr of prospective follow-up. Two-sample Mendelian randomization (MR) was conducted to assess causal associations between BMD and CMR metrics using genetic instrumental variables identified from published genome-wide association studies. The analysis included 485 257 participants (55% women, mean age 56.5 ± 8.1 yr). Higher heel eBMD was associated with lower odds of all prevalent CVDs considered. The greatest magnitude of effect was seen in association with HF and NICM, where 1-SD increase in eBMD was associated with 15% lower odds of HF and 16% lower odds of NICM. Association between eBMD and incident IHD and MI was non-significant; the strongest relationship was with incident HF (SHR: 0.90 [95% CI, 0.89-0.92]). Higher eBMD was associated with a decreased risk in all-cause, CVD, and IHD mortality, in the fully adjusted model. Higher eBMD was associated with greater aortic distensibility; associations with other CMR metrics were null. Higher heel eBMD is linked to reduced risk of a range of prevalent and incident CVD and mortality outcomes. Although observational analyses suggest associations between higher eBMD and greater aortic compliance, MR analysis did not support a causal relationship between genetically predicted BMD and CMR phenotypes. These findings support the notion that bone-cardiovascular associations reflect shared risk factors/mechanisms rather than direct causal pathways.

16.
JACC Cardiovasc Imaging ; 17(7): 746-762, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38613554

RESUMO

BACKGROUND: The absence of population-stratified cardiovascular magnetic resonance (CMR) reference ranges from large cohorts is a major shortcoming for clinical care. OBJECTIVES: This paper provides age-, sex-, and ethnicity-specific CMR reference ranges for atrial and ventricular metrics from the Healthy Hearts Consortium, an international collaborative comprising 9,088 CMR studies from verified healthy individuals, covering the complete adult age spectrum across both sexes, and with the highest ethnic diversity reported to date. METHODS: CMR studies were analyzed using certified software with batch processing capability (cvi42, version 5.14 prototype, Circle Cardiovascular Imaging) by 2 expert readers. Three segmentation methods (smooth, papillary, anatomic) were used to contour the endocardial and epicardial borders of the ventricles and atria from long- and short-axis cine series. Clinically established ventricular and atrial metrics were extracted and stratified by age, sex, and ethnicity. Variations by segmentation method, scanner vendor, and magnet strength were examined. Reference ranges are reported as 95% prediction intervals. RESULTS: The sample included 4,452 (49.0%) men and 4,636 (51.0%) women with average age of 61.1 ± 12.9 years (range: 18-83 years). Among these, 7,424 (81.7%) were from White, 510 (5.6%) South Asian, 478 (5.3%) mixed/other, 341 (3.7%) Black, and 335 (3.7%) Chinese ethnicities. Images were acquired using 1.5-T (n = 8,779; 96.6%) and 3.0-T (n = 309; 3.4%) scanners from Siemens (n = 8,299; 91.3%), Philips (n = 498; 5.5%), and GE (n = 291, 3.2%). CONCLUSIONS: This work represents a resource with healthy CMR-derived volumetric reference ranges ready for clinical implementation.


Assuntos
Voluntários Saudáveis , Imagem Cinética por Ressonância Magnética , Valor Preditivo dos Testes , Humanos , Pessoa de Meia-Idade , Masculino , Feminino , Adulto , Idoso , Valores de Referência , Adolescente , Adulto Jovem , Idoso de 80 Anos ou mais , Imagem Cinética por Ressonância Magnética/normas , Fatores Sexuais , Fatores Etários , Átrios do Coração/diagnóstico por imagem , Ventrículos do Coração/diagnóstico por imagem , Reprodutibilidade dos Testes , Etnicidade , Função Ventricular Esquerda , Fatores Raciais
17.
Light Sci Appl ; 12(1): 271, 2023 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-37957141

RESUMO

Smart contact lenses have recently gained traction due to their functionalization as noninvasive diagnostic and therapeutic wearables that can address several ocular diseases. Herein, multifunctional contact lenses exhibiting UV-transition and temperature-responsive capabilities were developed utilizing chromogenic materials that were integrated simultaneously into poly(2-hydroxyethyl methacrylate) (pHEMA) contact lenses. The functionalities of the contact lenses were optically evaluated in both their activated and non-activated states. Transition contact lenses offered excellent UV and blue light blocking capabilities (~45%) at their inactive states. When activated via UV exposure, the transparent lenses darkened instantaneously and absorbed portions of the visible light spectrum. The absorption intensity and transient discoloration of the transition lenses relied primarily on the utilized photochromic material. Likewise, the temperature-responsive contact lenses exhibited distinct colorimetric variations in response to temperature changes within the physiological range (33-38 °C). The maximum sensitivity of the thermochromic lens was 8% transmitted light per Celsius degree shift. Physiochemical and morphological analysis indicated the adequacy of the contact lenses. Hence, the multifunctional contact lenses can be deployed as smart wearables to manage ophthalmic deficiencies that are deterred by UV radiations and variations in ocular surface temperature.

18.
Heliyon ; 9(1): e12840, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36685372

RESUMO

Background: Although antiretroviral therapy (ART) is well accepted to increase survival of patients with HIV/AIDS, AIDS related deaths continue to be a major problem in sub-Saharan Africa like Ethiopia. Studies have showed variable findings in the survival status of patients with HIV/AIDS initiating ART, and there was no such study in the study area. Therefore, purpose of this study was to determine the survival and predictors of mortality among HIV/AIDS patients starting taking ART in Dubti General Hospital, Afar, Ethiopia. Methods: A 5 year retrospective cohort study was performed among 702 HIV/AIDS patients aged ≥15 years that started ART between December 31, 2010, and December 31, 2015 in Dubti General Hospital, Afar, Ethiopia. A simple random sampling technique was used to select the study subjects from each WHO stage based stratum. Socio-demographic, clinical and survival status data were extracted by reviewing patients' records. Data were analyzed by using SPSS Version 21. Kaplan-Meier and Cox-regression models were used to estimate survival, and explore predictors of mortality. Variables with a p value of <0.05 in multivariate Cox regression analysis were considered statistically significant. Results: Among 702 study participants, 82 (11.7%) died during follow up, and the overall incidence rate of mortality was 5.81 per 100 person-years. Identified predictors of mortality were being not married (AHR = 3.71, 95% CI: 1.97-6.99), had no formal education (AHR = 2.33, 95% CI: 1.33-4.38), bedridden functional status (AHR = 5.91, 95% CI: 2.71-12.88), advanced WHO stage III and IV (AHR = 4.36, 95% CI: 2.20-8.64), BMI 16-18.4 kg/m2 (AHR = 3.03, 95% CI: 1.50-6.13), and BMI<16.0 kg/m2 (AHR = 5.47; 95% CI: 2.85-10.50), CD4 count ≤50 cells/mm3 (AHR = 6.62, 95% CI: 4.73-8.52), hemoglobin <8 g/dl (AHR = 5.21; 95% CI: 2.64-10.26), not used cotrimoxazole prophylaxis therapy (AHR = 2.78, 95% CI: 1.61-4.73), stavudine based regimen (AHR = 2.34, 95% CI: 1.32-4.13), and zidovudine based regimen (AHR = 2.49, 95% CI: 1.41-4.39). Conclusion: High mortality was observed in this cohort, and participants with stage III and IV, low CD4 count, low hemoglobin level, bed ridden functional status, low BMI should be closely monitored even with the scarce resources. In addition, the use of cotrimoxazole prophylaxis therapy should be more encouraged to increase survival.

19.
ACS Biomater Sci Eng ; 9(7): 4381-4391, 2023 07 10.
Artigo em Inglês | MEDLINE | ID: mdl-37364228

RESUMO

3D printing of multimaterial objects is an emerging field with promising applications. The layer-by-layer material addition technique used in 3D printing enables incorporation of distinct functionalized materials into the specialized devices. However, very few studies have been performed on the usage of multimaterial 3D printing for printable photonic and wearable devices. Here, we employ vat photopolymerization-based 3D printing to produce multimaterial contact lenses, offering enhanced multiband optical filtration, which can be valuable for tackling ocular conditions such as color blindness. A combination of hydroxyethyl methacrylate (HEMA) and polyethylene glycol diacrylate (PEGDA) was used as the base hydrogel for 3D printing. Atto565 and Atto488 dyes were added to the hydrogel for wavelength filtering, each dye suitable for a different type of color blindness. Multimaterial disks and contact lenses, with separate sections containing distinct dyes, were 3D-printed, and their optical properties were studied. The characteristics of multimaterial printing were analyzed, focusing on the formation of a uniform multimaterial interface. In addition, a novel technique was developed for printing multiple dyed materials in complex lateral geometrical patterns, by employing suitable variations in CAD models and the UV curing time. It was observed that the multimaterial printing process does not negatively affect the optical properties of the contact lenses. The printed multimaterial contact lenses offered a combined multi-band color blindness correction due to the two dyes used. The resulting optical spectrum was a close match to the commercially available color blindness correction glasses.


Assuntos
Lentes de Contato , Impressão Tridimensional , Hidrogéis/química , Software , Teste de Materiais
20.
Aging Dis ; 14(3): 583-588, 2023 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-37191413

RESUMO

Chronological age is an imperfect measure of the aging process, which is affected by a wide range of genetic and environmental exposures. Biological age estimates may be derived using mathematical modelling with biomarkers set as predictors and chronological age as the output. The difference between biological and chronological age is denoted the "age gap" and considered a complementary indicator of aging. The utility of the "age gap" metric is assessed through examination of its associations with exposures of interest and the demonstration of additional information provided by this metric over chronological age alone. This paper reviews the key concepts of biological age estimation, the age gap metric, and approaches to assessment of model performance in this context. We further discuss specific challenges for the field, in particular the limited generalisability of effect sizes across studies owing to dependency of the age gap metric on pre-processing and model building methods. The discussion will be centred on brain age estimation, but the concepts are transferable to all biological age estimation.

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