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1.
Sleep Breath ; 26(3): 1087-1096, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-34448065

RESUMO

PURPOSE: To develop a novel non-invasive technique to quantify upper airway inflammation using positron emission tomography/magnetic resonance imaging (PET/MRI) in patients with obstructive sleep apnea (OSA). METHODS: Patients with treatment naïve moderate-to-severe OSA underwent [18F]-fluoro-2-deoxy-D-glucose (FDG) PET/MRI. Three readers independently performed tracings of the pharyngeal soft tissue on MRI. Standardized uptake values (SUV) were generated from region of interest (ROI) tracings on corresponding PET images. Background SUV was measured from the sternocleidomastoid muscle. SUV and target-to-background (TBR) were compared across readers using intraclass correlation coefficient (ICC) analyses. SUV from individual image slices were compared between each reader using Bland-Altman plots and Pearson correlation coefficients. All tracings were repeated by one reader for assessment of intra-reader reliability. RESULTS: Five participants completed our imaging protocol and analysis. Median age, body mass index, and apnea-hypopnea index were 41 years (IQR 40.5-68.5), 32.7 kg/m2 (IQR 28.1-38.1), and 30.7 event per hour (IQR 19.5-48.1), respectively. The highest metabolic activity regions were consistently localized to palatine or lingual tonsil adjacent mucosa. Twenty-five ICC met criteria for excellent agreement. The remaining three were TBR measurements which met criteria for good agreement. Head-to-head comparisons revealed strong correlation between each reader. CONCLUSIONS: Our novel imaging technique demonstrated reliable quantification of upper airway FDG avidity. This technology has implications for future work exploring local airway inflammation in individuals with OSA and exposure to pollutants. It may also serve as an assessment tool for response to OSA therapies.


Assuntos
Fluordesoxiglucose F18 , Apneia Obstrutiva do Sono , Adulto , Idoso , Humanos , Inflamação , Imageamento por Ressonância Magnética , Pessoa de Meia-Idade , Tomografia por Emissão de Pósitrons , Reprodutibilidade dos Testes
2.
Ann Oper Res ; : 1-31, 2021 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-34848908

RESUMO

The procurement of food grains from farmers is one of the biggest challenges under the COVID-19 outbreak due to country-wise lockdowns. The present study aims to reconfigure the existing food grain supply chain network. The study advances the extant literature by proposing a novel mathematical model that considers the government guidelines issued to procure food grains from farmers under the COVID-19 situation. The model includes personal distancing, a key parameter relevant in the COVID-19 crisis, and has remained unaddressed in the existing literature. The proposed model is tested in India. The effect of different parameters like personal distancing cost, carbon emission cost, fixed cost, and transportation cost is also investigated under a given set of procurement centers. Finally, the procurement schedule for each procurement center is generated, which is especially useful for managing its activities and is also helpful to farmers to streamline the process. Results indicate that the proposed model is highly effective under pandemic emergencies like the current COVID-19 crisis. Policymakers and the government will find this model helpful in drafting relevant policies regarding food grain procurement under emergencies such as the COVID-19 outbreak. The distribution segment of the supply chain network is not part of the present research work. In future studies, this part could be then added to the whole of the procurement process, and both procurement and distribution can be assessed together again.

3.
Ann Oper Res ; : 1-29, 2021 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-34776573

RESUMO

Credit risk imposes itself as a significant barrier of agriculture 4.0 investments in the supply chain finance (SCF) especially for Small and Medium-sized Enterprises. Therefore, it is important for financial service providers (FSPs) to differentiate between low- and high-quality SMEs to accurately forecast the credit risk. This study proposes a novel hybrid ensemble machine learning approach to forecast the credit risk associated with SMEs' agriculture 4.0 investments in SCF. Two core approaches were used, i.e., Rotation Forest algorithm and Logit Boosting algorithm. Key variables influencing the credit risk of agriculture 4.0 investments in SMEs were identified and evaluated using data collected from 216 agricultural SMEs, 195 Leading Enterprises and 104 FSPs operating in African agriculture sector. Besides the classical measures of credit risk assessment without involving SCF, the findings indicate that current ratio, financial leverage, profit margin on sales and growth rate of the agricultural SME are the upmost important variables that SCF actors need to focus on, in order to accurately and optimistically forecast and alleviate credit risk. The output of our study provides useful guidelines for SMEs, as it highlights the conditions under which they would be seen as creditworthy by FSPs. On the other hand, this study encourages the wide application of SCF in financing agriculture 4.0 investments. Due to the model's performance, credit risk forecasting accuracy is improved, which results in future savings and credit risk mitigation in agriculture 4.0 investments of SMEs in SCF.

5.
Sleep Breath ; 22(4): 1125-1135, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29508121

RESUMO

PURPOSE: Evidence suggests that the inflammatory state of an atherosclerotic plaque is important in predicting future risk of plaque rupture. This study aims to investigate the feasibility of measuring plaque inflammation in patients with obstructive sleep apnea (OSA) utilizing advanced vascular imaging - hybrid positron-emission tomography/magnetic resonance imaging (PET/MRI) with fluorodeoxyglucose (FDG) tracer-before and after continuous positive airway pressure (CPAP). METHODS: Patients with newly diagnosed moderate to severe OSA underwent baseline PET/MRI for assessment of vascular inflammation of the carotid arteries and thoracic aorta prior to initiation of CPAP. Those adherent to CPAP returned for repeat imaging after 3-6 months of CPAP use. Atherosclerotic plaque activity, as measured by arterial wall FDG uptake, was calculated using target-to-background ratios (TBR) before and after CPAP. RESULTS: Five patients were recruited as part of a focused project. Mean age was 52 years (80% male), and mean apnea-hypopnea index (AHI) was 33. Three patients were objectively adherent with CPAP. In the pre-CPAP phase, all patients had focal FDG uptake in the carotid arteries and aorta. After CPAP, there was an average reduction in TBR of 5.5% (TBRmean) and 6.2% (TBRmax) in carotid and aortic plaque inflammation, similar in magnitude to the reduction observed with statin therapy alone in non-OSA patients (previously reported by others). CONCLUSIONS: We demonstrate the feasibility of using hybrid PET/MRI to assess atherosclerotic plaque inflammation in patients with OSA before and after CPAP. Use of the vascular PET/MRI platform in patients with OSA may provide better insight into the role of OSA and its treatment in reducing atherosclerotic inflammation.


Assuntos
Pressão Positiva Contínua nas Vias Aéreas/métodos , Vasos Coronários/fisiopatologia , Placa Aterosclerótica/diagnóstico por imagem , Apneia Obstrutiva do Sono/fisiopatologia , Apneia Obstrutiva do Sono/terapia , Estudos de Viabilidade , Feminino , Humanos , Masculino , Imagem Multimodal , Placa Aterosclerótica/patologia , Placa Aterosclerótica/terapia , Tomografia por Emissão de Pósitrons , Índice de Gravidade de Doença , Apneia Obstrutiva do Sono/complicações , Resultado do Tratamento
6.
Am Heart J ; 187: 170-181, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28454800

RESUMO

BACKGROUND: The 2020 American Heart Association Impact Goal aims to improve cardiovascular health of all Americans by 20% while reducing deaths from cardiovascular disease and stroke by 20%. A large step toward this goal would be to better understand and take advantage of the significant intersection between behavior and biology across the entire life-span. In the proposed FAMILIA studies, we aim to directly address this major knowledge and clinical health gap by implementing an integrated family-centric health promotion intervention and focusing on the intersection of environment and behavior, while understanding the genetic and biologic basis of cardiovascular disease. METHODS: We plan to recruit 600 preschool children and their 600 parents or caregivers from 12-15 Head Start schools in Harlem, NY, and perform a 2:1 (2 intervention/1 control) cluster randomization of the schools. The preschool children will receive our intensive 37-hour educational program as the intervention for 4 months. For the adults, those in the "intervention" group will be randomly assigned to 1 of 2 intervention programs: an "individual-focused" or "peer-to-peer based." The primary outcome in children will be a composite score of knowledge (K), attitudes (A), habits (H), related to body mass index Z score (B), exercise (E), and alimentation (A) (KAH-BEA), using questionnaires and anthropometric measurements. For adults, the primary outcome will be a composite score for behaviors/outcomes related to blood pressure, exercise, weight, alimentation (diet) and tobacco (smoking; Fuster-BEWAT score). Saliva will be collected from the children for SNP genotyping, and blood will be collected from adults for RNA sequencing to identify network models and predictors of primary prevention outcomes. CONCLUSION: The FAMILIA studies seek to demonstrate that targeting a younger age group (3-5 years) and using a family-based approach may be a critical strategy in promoting cardiovascular health across the life-span.


Assuntos
Doenças Cardiovasculares/etnologia , Doenças Cardiovasculares/prevenção & controle , Promoção da Saúde/métodos , Grupos Minoritários/educação , Adulto , Índice de Massa Corporal , Pré-Escolar , Aconselhamento , Dieta Saudável , Intervenção Educacional Precoce , Exercício Físico , Educação em Saúde , Conhecimentos, Atitudes e Prática em Saúde , Humanos , New York , Projetos Piloto , Inquéritos e Questionários
7.
Nat Clin Pract Cardiovasc Med ; 6(3): 219-28, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19174763

RESUMO

BACKGROUND: The reliability of imaging techniques to assess early atherosclerosis remains unclear. We did a cross-sectional, prospective study to test reproducibility of MRI when imaging arteries, to assess risk of cardiovascular disease and correlations with age and sex. METHODS: Between January 2003 and December 2006 we performed black-blood MRI of both common carotid arteries and the thoracic descending aorta in patients with cardiovascular risk factors who were referred from clinics in New York, NY, USA. Mean wall area, wall thickness, lumen area, total vessel area, and ratio of the mean wall area to the mean total vessel area (WA/TVA) were manually measured. Reproducibility within and between readers was tested on subsets of images from randomly chosen patients. RESULTS: MRI was performed on 300 patients. Intrareader reproducibility, assessed in images from 20 patients, was high for all parameters (intraclass correlation coefficients >0.8), except WA/TVA ratio in the descending aorta. The inter-reader reproducibility, assessed in images from 187 patients, was acceptable (intraclass correlation coefficients >0.7) for the mean wall, lumen, and total vessel areas. Values for all MRI parameters in all vessels increased with increasing age for both sexes (all P <0.0005) but were always significantly higher in men than in women, except for aortic mean wall thickness and WA/TVA ratio in the carotid arteries. Mean wall area values correlated well between the carotid arteries and aorta, reflecting the systemic nature of atherosclerosis. CONCLUSIONS: Our findings support MRI as a reproducible measurement of plaque burden and demonstrate the systemic distribution of atherosclerosis.


Assuntos
Aorta Torácica , Doenças da Aorta/diagnóstico , Doenças das Artérias Carótidas/diagnóstico , Artéria Carótida Primitiva , Adolescente , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Criança , Estudos Transversais , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Reprodutibilidade dos Testes , Fatores de Risco
8.
J Cardiovasc Magn Reson ; 8(3): 529-34, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16755842

RESUMO

The aim of this study was to correlate carotid black blood MRI based measurements with those obtained by ultrasound intima-media thickness (IMT). Seventeen patients with intermediate to high Framingham cardiovascular risk score underwent both carotid ultrasound and rapid extended coverage double inversion recovery black blood carotid MRI. Overall, there was good correlation between wall area, wall thickness, and plaque index measured by MRI and the IMT measurements obtained from the ultrasound images (max r2 = 0.72, p < 0.05). Patients with mean IMT > or = 1.2 mm had significantly higher values of wall area, plaque index and wall thickness compared to patients with mean IMT < 1.2 mm. Vessel wall measurements assessed by black-blood MRI may be potentially used clinically to evaluate plaque progression and regression.


Assuntos
Arteriosclerose/patologia , Estenose das Carótidas/patologia , Imageamento por Ressonância Magnética/métodos , Túnica Íntima/diagnóstico por imagem , Túnica Média/diagnóstico por imagem , Idoso , Arteriosclerose/diagnóstico por imagem , Estenose das Carótidas/diagnóstico por imagem , Feminino , Humanos , Masculino , Medição de Risco , Fatores de Risco , Estatísticas não Paramétricas , Túnica Íntima/patologia , Túnica Média/patologia , Ultrassonografia
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