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1.
Comput Med Imaging Graph ; 109: 102294, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37713999

RESUMO

BACKGROUND: Brain stroke is a leading cause of disability and death worldwide, and early diagnosis and treatment are critical to improving patient outcomes. Current stroke diagnosis methods are subjective and prone to errors, as radiologists rely on manual selection of the most important CT slice. This highlights the need for more accurate and reliable automated brain stroke diagnosis and localization methods to improve patient outcomes. PURPOSE: In this study, we aimed to enhance the vision transformer architecture for the multi-slice classification of CT scans of each patient into three categories, including Normal, Infarction, Hemorrhage, and patient-wise stroke localization, based on end-to-end vision transformer architecture. This framework can provide an automated, objective, and consistent approach to stroke diagnosis and localization, enabling personalized treatment plans based on the location and extent of the stroke. METHODS: We modified the Vision Transformer (ViT) in combination with neural network layers for the multi-slice classification of brain CT scans of each patient into normal, infarction, and hemorrhage classes. For stroke localization, we used the ViT architecture and convolutional neural network layers to detect stroke and localize it by bounding boxes for infarction and hemorrhage regions in a patient-wise manner based on multi slices. RESULTS: Our proposed framework achieved an overall accuracy of 87.51% in classifying brain CT scan slices and showed high precision in localizing the stroke patient-wise. Our results demonstrate the potential of our method for accurate and reliable stroke diagnosis and localization. CONCLUSION: Our study enhanced ViT architecture for automated stroke diagnosis and localization using brain CT scans, which could have significant implications for stroke management and treatment. The use of deep learning algorithms can provide a more objective and consistent approach to stroke diagnosis and potentially enable personalized treatment plans based on the location and extent of the stroke. Further studies are needed to validate our method on larger and more diverse datasets and to explore its clinical utility in real-world settings.


Assuntos
Encéfalo , Acidente Vascular Cerebral , Humanos , Encéfalo/diagnóstico por imagem , Acidente Vascular Cerebral/diagnóstico por imagem , Tomografia Computadorizada por Raios X , Hemorragia , Infarto
2.
Comput Med Imaging Graph ; 109: 102295, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37717365

RESUMO

BACKGROUND: Medical image classification is crucial for accurate and efficient diagnosis, and deep learning frameworks have shown significant potential in this area. When a general learning deep model is directly deployed to a new dataset with heterogeneous features, the effect of domain shifts is usually ignored, which degrades the performance of deep learning models and leads to inaccurate predictions. PURPOSE: This study aims to propose a framework that utilized the cross-modality domain adaptation and accurately diagnose and classify MRI scans and domain knowledge into stable and vulnerable plaque categories by a modified Vision Transformer (ViT) model for the classification of MRI scans and transformer model for domain knowledge classification. METHODS: This study proposes a Hybrid Vision Inspired Transformer (HViT) framework that employs a convolutional layer for image pre-processing and normalization and a 3D convolutional layer to enable ViT to classify 3D images. Our proposed HViT framework introduces a slim design with a multi-branch network and channel attention, improving patch embedding extraction and information learning. Auxiliary losses target shallow features, linking them with deeper ones, enhancing information gain, and model generalization. Furthermore, replacing the MLP Head with RNN enables better backpropagation for improved performance. Moreover, we utilized a modified transformer model with LSTM positional encoding and Golve word vector to classify domain knowledge. By using ensemble learning techniques, specifically stacking ensemble learning with hard and soft prediction, we combine the predictive power of both models to address the cross-modality domain adaptation problem and improve overall performance. RESULTS: The proposed framework achieved an accuracy of 94.32% for carotid artery plaque classification into stable and vulnerable plaque by addressing the cross-modality domain adaptation problem and improving overall performance. CONCLUSION: The model was further evaluated using an independent dataset acquired from different hardware protocols. The results demonstrate that the proposed deep learning model significantly improves the generalization ability across different MRI scans acquired from different hardware protocols without requiring additional calibration data.


Assuntos
Estenose das Carótidas , Humanos , Estenose das Carótidas/diagnóstico por imagem , Imageamento por Ressonância Magnética , Calibragem , Processamento de Imagem Assistida por Computador
3.
J Am Med Dir Assoc ; 24(5): 664-671.e7, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36574953

RESUMO

OBJECTIVES: To determine the impact of depressive symptoms on health service use and catastrophic health expenditure, and whether it varied by per-capita household consumption, health insurance schemes, and physical comorbidities. DESIGN: Population-based panel data analysis. SETTING AND PARTICIPANTS: Participants were 8585 adults aged 45 years and older in 2011, and had completed a follow-up survey in 2013, 2015, and 2018 from the China Health and Retirement Longitudinal Study (CHARLS). METHODS: Depressive symptoms were assessed using the short form of the Center for Epidemiologic Studies Depression Scale. The number of outpatient visits and inpatient hospital days were used as proxies for health service use. When households' out-of-pocket spending on health was 40% or above its total expenditure, it was defined as a catastrophic health expenditure. With the panel data approach, random-effects negative binomial regression and logistic regression were used to analyze the effect of depressive symptoms on health service use and health care expenditure, respectively. RESULTS: Depressive symptoms were associated with increased number of outpatient visits (incidence rate ratio 1.52; 95% CI 1.44-1.60) and days spent in the hospital as an inpatient (1.52; 1.43-1.62). Depressive symptoms were also associated with a significantly increased likelihood of catastrophic health expenditure (odds ratio 1.54; 95% CI 1.43-1.66). Their effect on outpatient visits, inpatient hospital days, and catastrophic health expenditure persisted in different age, per-capita household consumption, and physical comorbidities groups, and across all health insurance programs. CONCLUSIONS AND IMPLICATIONS: Depressive symptoms were risk indicators that can drive health service use and household financial stress. Given the rapidly aging population in China, there is an urgent need to integrate mental health care into routine physical examinations to alleviate the economic impacts of depressive symptoms on individuals in China. specifically for individuals with physical comorbidities and in poorer socioeconomic conditions.


Assuntos
Depressão , Gastos em Saúde , Pessoa de Meia-Idade , Humanos , Adulto , Idoso , Depressão/epidemiologia , Estudos Longitudinais , População do Leste Asiático , China/epidemiologia , Aceitação pelo Paciente de Cuidados de Saúde
4.
Cancer Rep (Hoboken) ; 6(2): e1688, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-35892165

RESUMO

The postoperative recurrence of neuroblastoma (NB) patients is an essential reason for the high mortality of NB due to the lack of early, non-invasive, and dynamic strategies for monitoring NB recurrence. Therefore, whether the plasma circulating cell-free MYCN gene as an indicator for monitoring of NB recurrence was systematically evaluated. The MYCN copy number and NAGK (reference gene) copy number (M/N) ratio in plasma and corresponding tumor tissues of NB patients was detected using an economical, sensitive, and specific single-tube dual RT-PCR approach developed in this study. The plasma M/N ratio of the MYCN gene amplification (MNA) group (N = 25, median M/N ratio = 4.90) was significantly higher than that of the non-MNA group (N = 71, median M/N ratio = 1.22), p < .001. The M/N ratio in NB plasma (N = 60) was positively correlated with the M/N ratio in NB tumor tissue (N = 60), with a correlation coefficient of 0.9496. In particular, the results of dynamic monitoring of postoperative plasma M/N ratio of NB patients showed that an abnormal increase in M/N ratio could be detected 1-2 months before recurrence in NB patients. In summary, the single-tube double RT-PCR approach can be used to quantitatively detect MYCN copy number. The copy number of MYCN in the tissue and plasma of NB patients is consistent with each other. More importantly, the circulating cell-free MYCN gene of NB patients can be used as a monitoring indicator for early, non-invasive, and dynamic monitoring of NB recurrence.


Assuntos
Neuroblastoma , Proteínas Nucleares , Humanos , Proteína Proto-Oncogênica N-Myc/genética , Proteínas Nucleares/genética , Proteínas Oncogênicas/genética , Proteínas Oncogênicas/metabolismo , Neuroblastoma/genética , Regulação Neoplásica da Expressão Gênica
5.
Environ Pollut ; 266(Pt 2): 115119, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32623072

RESUMO

The extensive use of neonicotinoids (NEOs) has caused the release of wide-ranging of residues to the environment and food, and their potential health risks are now receiving more attention. In this study, three surveys were conducted to obtain the overall profiles of NEO residue levels (seven NEOs and one metabolite) in Chinese tea over a period of seven years. A total of 726 tea samples were tested, and nearly 87% of the samples were found to have detectable NEO residues. The overall average detection frequency of acetamiprid was the highest, reaching 73%. Imidacloprid residues in 4.6% of the samples exceeded the Chinese maximum residue limits, whereas clothianidin and nitenpyram had been detected in Chinese tea samples since 2014. The applications of thiacloprid and thiamethoxam gradually increased, and some tea samples with high residue levels appeared in China. These findings signal the replacement of new and old varieties of NEOs in China. Both long- and short-term cumulative exposures to NEOs were calculated based on optimistic and pessimistic models recommended in the EFSA guidelines. In the three survey periods, the average total imidacloprid-equivalent concentrations were 484.63, 1713.36, and 1148.34 µg/kg, respectively. Combined with the refined point estimates and probabilistic models used in this study, the hazard quotients of NEO residues in tea for Chinese tea consumers were found to be low and within the bounds of safety.


Assuntos
Inseticidas/análise , China , Neonicotinoides , Nitrocompostos/análise , Medição de Risco , Chá
6.
Food Chem ; 328: 127113, 2020 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-32474239

RESUMO

In view of the high polarity and ubiquitous occurrence of perchlorate, achieving an ultra-trace analysis has become a challenging task. The present study aimed to develop a simple and generic pretreatment protocol based on cold-induced liquid-liquid extraction to efficiently extract perchlorate from tea and dairy products and remarkably decrease potential matrix interferences and laborious cleanup. By optimizing the pretreatment conditions, the enrichment factor of perchlorate increased by 7.79 times under the compromise between the matrix effect and extraction recovery. The validated method presented satisfactory selectivity, linearity, accuracy, precision, and matrix effect, providing recoveries of 78.2%-106.2% with RSDr ranging from 1.2% to 7.9% and RSDR less than 10.7% for tea and dairy products. This pretreatment protocol depended only on shaking, freezing, and centrifugation in one step, without additional equipment or tedious operations, which will be explored to a greater extent in complex biological or food matrices.


Assuntos
Laticínios/análise , Análise de Alimentos/métodos , Contaminação de Alimentos/análise , Extração Líquido-Líquido/métodos , Percloratos/análise , Chá/química , Centrifugação/métodos , Análise Custo-Benefício , Análise de Alimentos/economia , Congelamento , Extração Líquido-Líquido/economia , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Fatores de Tempo
7.
Alcohol Clin Exp Res ; 39(11): 2179-88, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26463727

RESUMO

BACKGROUND: In the current report, we ask if targeting a cognitive behavioral therapy (CBT)-based intervention aimed at reducing hazardous alcohol consumption to HIV-infected persons in East Africa would have a favorable value at costs that are feasible for scale-up. METHODS: Using a computer simulation to inform HIV prevention decisions in East Africa, we compared 4 different strategies for targeting a CBT intervention-(i) all HIV-infected persons attending clinic; (ii) only those patients in the pre-antiretroviral therapy (ART) stages of care; (iii) only those patients receiving ART; and (iv) only those patients with detectable viral loads (VLs) regardless of disease stage. We define targeting as screening for hazardous alcohol consumption (e.g., using the Alcohol Use Disorders Identification Test and offering the CBT intervention to those who screen positive). We compared these targeting strategies to a null strategy (no intervention) or a hypothetical scenario where an alcohol intervention was delivered to all adults regardless of HIV status. RESULTS: An intervention targeted to HIV-infected patients could prevent 18,000 new infections, add 46,000 quality-adjusted life years (QALYs), and yield an incremental cost-effectiveness ratio of $600/QALY compared to the null scenario. Narrowing the prioritized population to only HIV-infected patients in pre-ART phases of care results in 15,000 infections averted, the addition of 21,000 QALYs and would be cost-saving, while prioritizing based on an unsuppressed HIV-1 VL test results in 8,300 new infections averted, adds 6,000 additional QALYs, and would be cost-saving as well. CONCLUSIONS: Our results suggest that targeting a cognitive-based treatment aimed at reducing hazardous alcohol consumption to subgroups of HIV-infected patients provides favorable value in comparison with other beneficial strategies for HIV prevention and control in this region. It may even be cost-saving under certain circumstances.


Assuntos
Consumo de Bebidas Alcoólicas/economia , Consumo de Bebidas Alcoólicas/epidemiologia , Simulação por Computador , Análise Custo-Benefício/métodos , Infecções por HIV/economia , Infecções por HIV/epidemiologia , Síndrome da Imunodeficiência Adquirida/diagnóstico , Síndrome da Imunodeficiência Adquirida/economia , Síndrome da Imunodeficiência Adquirida/epidemiologia , Adulto , África Oriental/epidemiologia , Consumo de Bebidas Alcoólicas/terapia , Intervenção Médica Precoce/economia , Intervenção Médica Precoce/métodos , Feminino , Infecções por HIV/diagnóstico , Humanos , Masculino , Ensaios Clínicos Controlados Aleatórios como Assunto/economia , Ensaios Clínicos Controlados Aleatórios como Assunto/métodos
8.
J Phys Act Health ; 11(2): 303-12, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23363569

RESUMO

BACKGROUND: Physical activity (PA) has been routinely linked to lower all-cause mortality, yet extant research in the United States is primarily based on nonrepresentative samples. Evidence is scant on the relative and independent merits of leisure-time (LTPA) versus non-leisure-time (NLTPA) activities and how the PA-mortality link may vary across racial-ethnic-gender groups. METHODS: Data were from Health and Retirement Study which began in 1992 collecting data on individuals aged 51-61 years who were subsequently surveyed once every 2 years. The current study assessed group-specific effects of LTPA and NLTPA measured in 1992 on mortality that occurred during the 1992-2008 follow-up period. Cox proportional hazard analyses were performed to examine the PA-mortality link. RESULTS: Net of a wide range of controls, both LTPA and NLTPA showed a gradient negative relation with mortality. No gender-PA interaction effects were evident. Some interaction effects of PA with race-ethnicity were found but they were weak and inconsistent. The mortality reduction effects of PA seemed robust across racial-ethnic-gender groups. CONCLUSIONS: Regardless of personal background, PA is a major health promoting factor and should be encouraged in aging populations. More research is needed to assess relative merits of different types and domains of PA.


Assuntos
Envelhecimento/etnologia , Etnicidade/estatística & dados numéricos , Atividades de Lazer , Mortalidade/etnologia , Atividade Motora , Feminino , Seguimentos , Humanos , Entrevistas como Assunto , Masculino , Pessoa de Meia-Idade , Vigilância da População , Modelos de Riscos Proporcionais , Estudos Prospectivos , Fatores Socioeconômicos , Estados Unidos/epidemiologia
9.
J Biosoc Sci ; 44(4): 417-32, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22214551

RESUMO

Using recent pooled data from the World Health Organization Global Infobase and the World Factbook compiled by the Central Intelligence Agency of the United States, this study assesses the relation between income inequality and obesity prevalence among 31 OECD countries through a series of bivariate and multivariate linear regressions. The United States and Mexico well lead OECD countries in both obesity prevalence and income inequality. A sensitivity analysis suggests that the inclusion or exclusion of these two extreme cases can fundamentally change the findings. When the two countries are included, the results reveal a positive correlation between income inequality and obesity prevalence. This correlation is more salient among females than among males. Income inequality alone is associated with 16% and 35% of the variations in male and female obesity rates, respectively, across OECD countries in 2010. Higher levels of income inequality in the 2005-2010 period were associated with a more rapid increase in obesity prevalence from 2002 to 2010. These associations, however, virtually disappear when the US and Mexico have been excluded from the analysis. Findings from this study underscore the importance of assessing the impact of extreme cases on the relation between income inequality and health outcomes. The potential pathways from income inequality to the alarmingly high rates of obesity in the cases of the US and Mexico warrant further research.


Assuntos
Disparidades nos Níveis de Saúde , Renda/estatística & dados numéricos , Obesidade/epidemiologia , Classe Social , Fatores Socioeconômicos , Índice de Massa Corporal , Países em Desenvolvimento , Feminino , Humanos , Modelos Lineares , Masculino , Análise Multivariada , Prevalência , Fatores de Risco , Fatores Sexuais , Estatística como Assunto
10.
J Health Care Poor Underserved ; 22(1): 296-310, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21317523

RESUMO

In this study we seek to assess recent trends in complementary and alternative medicine (CAM) use based on a comparative analysis of data from the 2002 and 2007 National Health Interview Survey (NHIS). The findings suggest that CAM use, in particular the use of provider-based CAM therapies such as chiropractic care, massage, and acupuncture, have grown significantly in the U.S. This growth was more pronounced among non-Hispanic Whites than among racial and ethnic minorities, increasing an already existing White-minority gap in CAM use. Findings from this study also reveal that CAM use becomes more likely when access to conventional care has been restricted. In both 2002 and 2007, having unmet needs in medical care or having delayed care due to cost were associated with a higher chance of CAM use.


Assuntos
Terapias Complementares/estatística & dados numéricos , Grupos Minoritários/psicologia , Aceitação pelo Paciente de Cuidados de Saúde/etnologia , População Branca/psicologia , Negro ou Afro-Americano/psicologia , Negro ou Afro-Americano/estatística & dados numéricos , Asiático/psicologia , Asiático/estatística & dados numéricos , Terapias Complementares/tendências , Pesquisas sobre Atenção à Saúde , Necessidades e Demandas de Serviços de Saúde , Disparidades em Assistência à Saúde/economia , Disparidades em Assistência à Saúde/etnologia , Hispânico ou Latino/psicologia , Hispânico ou Latino/estatística & dados numéricos , Humanos , Grupos Minoritários/estatística & dados numéricos , Fatores de Tempo , Estados Unidos , População Branca/estatística & dados numéricos
11.
J Opt Soc Am A Opt Image Sci Vis ; 24(4): 1085-96, 2007 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17361296

RESUMO

This work reduces the computation cost of the C method by taking into account the symmetries of grating grooves. All one-dimensionally periodic, single-interface, surface-relief gratings are classified into five categories according to the symmetries of the planar periodic curves describing the interface. The five categories are reflection symmetry, inversion symmetry, reflection-translation symmetry, complete symmetry (i.e., simultaneous existence of all three aforementioned symmetries), and no symmetry. Reductions of the eigenvalue problem in the C method are first carried out in real space and then in Fourier space by taking advantage of the four types of symmetries. The reflection-translation symmetry can be used without any restriction on the incident angle, but the other symmetries require a Littrow mounting; simultaneous use of the reflection-translation symmetry with any other symmetry further requires an even-order Littrow mounting. The types of eigenfunctions to be solved and boundary conditions to be matched, as well as the time reduction ratios in solving the eigenvalue problem, are given for all possible combinations of groove symmetries and incident configurations. The time reduction ratios range from 1/4 to 1/64.


Assuntos
Algoritmos , Aumento da Imagem/métodos , Interpretação de Imagem Assistida por Computador/métodos , Modelos Teóricos , Refratometria/métodos , Simulação por Computador , Análise Numérica Assistida por Computador
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