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1.
J Neurol Neurosurg Psychiatry ; 95(1): 44-51, 2023 Dec 14.
Artículo en Inglés | MEDLINE | ID: mdl-37558399

RESUMEN

OBJECTIVES: Alzheimer's disease (AD) is characterised by amyloid-beta accumulation (A), tau aggregation (T) and neurodegeneration (N). Vascular (V) burden has been found concomitantly with AD pathology and has synergistic effects on cognitive decline with AD biomarkers. We determined whether cognitive trajectories of AT(N) categories differed according to vascular (V) burden. METHODS: We prospectively recruited 205 participants and classified them into groups based on the AT(N) system using neuroimaging markers. Abnormal V markers were identified based on the presence of severe white matter hyperintensities. RESULTS: In A+ category, compared with the frequency of Alzheimer's pathological change category (A+T-), the frequency of AD category (A+T+) was significantly lower in V+ group (31.8%) than in V- group (64.4%) (p=0.004). Each AT(N) biomarker was predictive of cognitive decline in the V+ group as well as in the V- group (p<0.001). Additionally, the V+ group showed more severe cognitive trajectories than the V- group in the non-Alzheimer's pathological changes (A-T+, A-N+; p=0.002) and Alzheimer's pathological changes (p<0.001) categories. CONCLUSION: The distribution and longitudinal outcomes of AT(N) system differed according to vascular burdens, suggesting the importance of incorporating a V biomarker into the AT(N) system.


Asunto(s)
Enfermedad de Alzheimer , Disfunción Cognitiva , Humanos , Enfermedad de Alzheimer/patología , Péptidos beta-Amiloides , Neuroimagen/métodos , Disfunción Cognitiva/complicaciones , Biomarcadores , Proteínas tau
2.
Proc Natl Acad Sci U S A ; 117(39): 24144-24153, 2020 09 29.
Artículo en Inglés | MEDLINE | ID: mdl-32934147

RESUMEN

Voluntary physical distancing is essential for preventing the spread of COVID-19. We assessed the role of political partisanship in individuals' compliance with physical distancing recommendations of political leaders using data on mobility from a sample of mobile phones in 3,100 counties in the United States during March 2020, county-level partisan preferences, information about the political affiliation of state governors, and the timing of their communications about COVID-19 prevention. Regression analyses examined how political preferences influenced the association between governors' COVID-19 communications and residents' mobility patterns. Governors' recommendations for residents to stay at home preceded stay-at-home orders and led to a significant reduction in mobility that was comparable to the effect of the orders themselves. Effects were larger in Democratic- than in Republican-leaning counties, a pattern more pronounced under Republican governors. Democratic-leaning counties also responded more strongly to recommendations from Republican than from Democratic governors. Political partisanship influences citizens' decisions to voluntarily engage in physical distancing in response to communications by their governor.


Asunto(s)
Infecciones por Coronavirus/prevención & control , Adhesión a Directriz , Liderazgo , Pandemias/prevención & control , Neumonía Viral/prevención & control , Política , Betacoronavirus , COVID-19 , Comunicación , Infecciones por Coronavirus/epidemiología , Gobierno , Adhesión a Directriz/estadística & datos numéricos , Humanos , Neumonía Viral/epidemiología , Política Pública , SARS-CoV-2 , Factores de Tiempo , Viaje/estadística & datos numéricos , Estados Unidos/epidemiología
3.
AIDS Behav ; 25(9): 2793-2800, 2021 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-34076813

RESUMEN

Although considerable research has examined the influence of parent-adolescent relationships on the sexual health of adolescents, there is a great need for research to understand the influence of fathers on their children's HIV sexual risk behavior, particularly in sub-Saharan Africa. We examined how the residence and the involvement of fathers are related to their children's HIV sexual risk and alcohol consumption behaviors. A cross-sectional survey was completed by 175 sixth-grade adolescents in the Eastern Cape Province, South Africa. Analyses showed that adolescents living with their fathers had fewer sexual partners (B = - 0.606, SE = 0.299, p = .043) and consumed alcohol less frequently (B = - 0.642, SE = 0.294, p = .029). Adolescents who spent more quality days with their fathers in the past 30 days had fewer sexual partners (B = - 0.103, SE = 0.039, p = .008) and had condomless sex less frequently (B = - 0.097, SE = 0.047, p = 0.041). It was also found that there were significant father-residence × child-gender interactions on sexual debut (B = 1.132, SE = 0.564, p = .045) and on frequency of condomless sex (B = - 2.140, SE = 0.924, p = .021). These interactions indicate that boys living with their fathers were less likely to have had vaginal intercourse than girls and that girls living with their fathers were less likely to have unprotected sex than boys. This study highlights the importance of South African fathers' roles in their adolescent children's HIV sexual risk and alcohol drinking behaviors and the need to promote father-child relationships for adolescent health. The results suggest that health programs aiming to reduce South African adolescents' HIV sexual risk behaviors and alcohol consumption consider strategies that target their fathers.


Asunto(s)
Conducta del Adolescente , Infecciones por VIH , Adolescente , Consumo de Bebidas Alcohólicas/epidemiología , Estudios Transversales , Padre , Femenino , Infecciones por VIH/epidemiología , Infecciones por VIH/prevención & control , Humanos , Masculino , Asunción de Riesgos , Conducta Sexual , Sudáfrica/epidemiología
4.
Health Educ Res ; 36(2): 224-238, 2021 04 12.
Artículo en Inglés | MEDLINE | ID: mdl-33638647

RESUMEN

Parent-child sexual-health communication is critical. Religious involvement is important in many African-American families, but can be a barrier to sexual-health communication. We tested a theory-based, culturally tailored intervention to increase sexual-abstinence communication among church-attending African-American parent-child dyads. In a randomized controlled trial, 613 parent-child dyads were randomly assigned to one of three 3-session interventions: (i) faith-based abstinence-only; (ii) non-faith-based abstinence-only; or (iii) attention-matched health-promotion control. Data were collected pre- and post-intervention, and 3-, 6-, 12- and 18-months post-intervention. Generalized-estimating-equations Poisson-regression models revealed no differences in communication by intervention arm. However, three-way condition � sex-of-child � sex-of-parent interactions on children's reports of parent-child communication about puberty [IRR=0.065, 95% CI: (0.010, 0.414)], menstruation or wet dreams [IRR=0.103, 95% CI: (0.013, 0.825)] and dating [IRR=0.102, 95% CI: (0.016, 0.668)] indicated that the non-faith-based abstinence intervention's effect on increasing communication was greater with daughters than with sons, when the parent was the father. This study highlights the importance of considering parent and child gender in the efficacy of parent-child interventions and the need to tailor interventions to increase fathers' comfort with communication.


Asunto(s)
Negro o Afroamericano , Salud Sexual , Cuidadores , Niño , Comunicación , Femenino , Humanos , Relaciones Padres-Hijo , Conducta Sexual
5.
J Community Health ; 46(6): 1099-1106, 2021 12.
Artículo en Inglés | MEDLINE | ID: mdl-33963984

RESUMEN

African American men living with HIV are at high risk of colorectal cancer (CRC). Screening to detect CRC is associated with a reduced risk of CRC mortality. However, little is known about CRC screening predictors in this population. This study examined the relation of self-efficacy, a potential mediator of screening that interventions could target, to CRC screening. It also investigated several variables that might identify subpopulations of African American men non-adherent to CRC screening recommendations. We report a secondary analysis on baseline data from a randomized controlled trial of a health promotion intervention for African American men living with HIV. Before their intervention, they completed measures of CRC screening, self-efficacy, marital status, age, education, and adherence to physical activity guidelines and were assessed for obesity. A total of 270 African American men aged 45 to 88 (Mean = 55.07; SD = 6.46) living with HIV participated. About 30% reported CRC screening in the past six months. Multiple logistic regression revealed greater CRC screening self-efficacy and meeting physical activity guidelines were associated with receiving CRC screening. Obese men and men reporting higher education were less likely to report screening. Age and marital status were unrelated to screening. The results of this study suggest CRC screening rates may be low among African American men living with HIV, and interventions targeting self-efficacy may improve their screening uptake. Moreover, public-health efforts to increase screening should prioritize interventions with subpopulations of African American men living with HIV who are physically inactive and obese.


Asunto(s)
Neoplasias Colorrectales , Infecciones por VIH , Negro o Afroamericano , Neoplasias Colorrectales/diagnóstico , Detección Precoz del Cáncer , Infecciones por VIH/diagnóstico , Humanos , Masculino , Tamizaje Masivo
6.
Neurol Sci ; 40(2): 311-317, 2019 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-30415448

RESUMEN

INTRODUCTION: Patients with Parkinson's disease (PD) present a variety of non-motor symptoms. However, it remains unclear whether dopamine depletion is related to non-motor symptoms, and which non-motor symptoms are significantly dependent on dopaminergic deficit. METHODS: Forty-one patients with PD who underwent positron emission tomography imaging of dopamine transporters (DATs) were recruited for this study. The striatum was divided into 12 subregions, and DAT activity, as striatal dopaminergic concentration, was calculated in each subregion. In addition to measuring motor symptoms using the Unified Parkinson's Disease Rating Scale-part III (UPDRS-III), various non-motor symptoms were assessed using the Montreal cognitive assessment, frontal assessment battery, Beck depression inventory (BDI), Beck anxiety inventory, PD sleep scale (PDSS), PD fatigue scale, and non-motor symptoms scale (NMSS) for PD. RESULTS: For simple linear regression analyses, dopaminergic depletion in all striatal subregions was negatively correlated with the UPDRS-III score. The most relevant non-motor symptom assessment related to dopaminergic loss in the 12 subregions was NMSS, followed by BDI and PDSS. However, following multiple linear regression analyses, dopaminergic depletion in the 12 striatal subregions was not related with any of the non-motor symptoms. Conversely, dopaminergic deficit in the right anterior and posterior putamen was associated with the UPDRS-III score. CONCLUSIONS: Striatal dopaminergic depletion was not significantly correlated with any of the various non-motor symptoms in PD. Our findings suggest that non-dopaminergic systems are significantly implicated in the pathogenesis of non-motor symptoms in patients with PD.


Asunto(s)
Cuerpo Estriado/diagnóstico por imagen , Cuerpo Estriado/metabolismo , Proteínas de Transporte de Dopamina a través de la Membrana Plasmática/metabolismo , Enfermedad de Parkinson/diagnóstico por imagen , Enfermedad de Parkinson/metabolismo , Tomografía de Emisión de Positrones , Anciano , Antiparkinsonianos/uso terapéutico , Mapeo Encefálico , Dopamina/deficiencia , Dopaminérgicos/uso terapéutico , Femenino , Humanos , Imagen por Resonancia Magnética , Masculino , Enfermedad de Parkinson/tratamiento farmacológico , Enfermedad de Parkinson/psicología , Escalas de Valoración Psiquiátrica , Radiofármacos , Estudios Retrospectivos , Índice de Severidad de la Enfermedad , Tropanos
7.
Ann Neurol ; 82(5): 850-854, 2017 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-29059491

RESUMEN

This study analyzed data from dopamine transporter (DAT) positron emission tomographic scans of 282 male patients with de novo Parkinson disease to investigate whether smoking impacts striatal dopamine neuronal degeneration. Mean DAT activity in the posterior (p = 0.016) and ventral putamen (p = 0.028) was higher in 44 current smokers in comparison to 105 ex-smokers and 133 never-smokers. The severity of baseline motor deficits and the longitudinal increases in levodopa-equivalent doses during follow-up were similar among the 3 groups. These results suggest that current smoking, but not past smoking, protects dopamine neuronal degeneration in the sensorimotor striatum with no additional clinical benefits. Ann Neurol 2017;82:850-854.


Asunto(s)
Neuronas Dopaminérgicas/patología , Degeneración Nerviosa/inducido químicamente , Enfermedad de Parkinson/patología , Fumar/patología , Anciano , Estudios de Casos y Controles , Cuerpo Estriado/patología , Proteínas de Transporte de Dopamina a través de la Membrana Plasmática/metabolismo , Neuroimagen Funcional , Humanos , Masculino , Persona de Mediana Edad , Tomografía de Emisión de Positrones , Factores Protectores , Tropanos/metabolismo
8.
Eur J Nucl Med Mol Imaging ; 45(9): 1585-1595, 2018 07.
Artículo en Inglés | MEDLINE | ID: mdl-29728749

RESUMEN

PURPOSE: The purpose of this study was to evaluate whether the pattern of striatal dopamine transporter (DAT) availability could differentiate between progressive supranuclear palsy (PSP) and frontotemporal dementia (FTD) in the first few years of the disease. METHODS: We enrolled patients who had Parkinsonism and frontal dysfunction and/or language deficit, visited the clinic within 2 years of the onset of symptoms, and had been followed-up for longer than 5 years; thus resulting in 26 patients with PSP and 24 patients with FTD. By quantitatively analyzing N-(3-[18F]fluoropropyl)-2ß-carbon ethoxy-3ß-(4-iodophenyl) nortropane PET, we compared the pattern of DAT availability at the time of the baseline evaluation between the two groups. The discriminatory power of variables including DAT activity and clinical parameters was investigated by receiver operating characteristics (ROC) analyses. Additionally, we analyzed the correlation between striatal subregional DAT availability and cognitive profiles. RESULTS: Patients with PSP and FTD had significantly lower DAT availability than normal controls in the whole striatum and in each striatal subregion. When comparing the two groups, DAT availability was significantly lower in patients with PSP than those with FTD in all striatal subregions. The PSP and FTD groups had generally similar subregional patterns of DAT activity in terms of the anteroposterior and ventrodorsal gradients and asymmetry, except for a different preferential involvement in the caudate. The ROC analysis showed that the DAT activity of the whole striatum had an excellent discriminatory power relative to Parkinsonism or neurocognitive profiles. Correlation analysis showed that verbal memory was significantly correlated with DAT availability in the whole striatum and the putaminal subregion only in patients with PSP. CONCLUSIONS: DAT scans have prognostic value in determining whether patients with Parkinsonism and behavioral and/or language dysfunction will develop features of PSP or FTD later in the disease course.


Asunto(s)
Demencia Frontotemporal/diagnóstico por imagen , Parálisis Supranuclear Progresiva/diagnóstico por imagen , Tomografía Computarizada de Emisión de Fotón Único , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Tropanos
9.
J Surg Oncol ; 118(4): 644-650, 2018 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-30132891

RESUMEN

BACKGROUND: Recurrent laryngeal/hypopharyngeal squamous cell carcinoma (LHSCC) is commonly associated with poor survival outcomes. We evaluated the prognostic role of 18 F-fluorodeoxyglucose positron emission tomography/computed tomography (18 F-FDG PET/CT) parameters quantitatively measured in patients who underwent salvage treatments for recurrent LHSCC. METHODS: This study involved 100 consecutive LHSCC patients who underwent 18 F-FDG PET/CT for recurrent staging and subsequent salvage treatments. Maximum standardized uptake value (SUVmax ), metabolic tumor volume (MTV), and total lesion glycolysis (TLG) were measured using 18 F-FDG PET/CT. Cox proportional hazards regression analyses were used to assess the associations between quantitative 18 F-FDG PET/CT parameters and other clinicopathological factors with progression-free survival (PFS) and overall survival (OS). RESULTS: Two-year postsalvage PFS and OS rates were 67.9% and 74.3%, respectively. All 18 F-FDG PET parameters of SUVmax , MTV, and TLG were significantly associated with poor PFS and OS outcomes after salvage treatment (all P < 0.05). Multivariate analyses revealed that recurrence site, MTV (>6.5 mL), and TLG (>17.1 g) were independent variables predictive of PFS. Karnofsky score, SUVmax (>4.0), and TLG (>17.1 g) were the independent prognostic factors for OS. CONCLUSIONS: 18 F-FDG PET/CT can be useful in predicting postsalvage recurrence and survival in patients with recurrent LHSCC.


Asunto(s)
Carcinoma de Células Escamosas/patología , Fluorodesoxiglucosa F18/metabolismo , Neoplasias Hipofaríngeas/patología , Neoplasias Laríngeas/patología , Recurrencia Local de Neoplasia/patología , Tomografía Computarizada por Tomografía de Emisión de Positrones/métodos , Terapia Recuperativa , Anciano , Carcinoma de Células Escamosas/diagnóstico por imagen , Carcinoma de Células Escamosas/metabolismo , Carcinoma de Células Escamosas/terapia , Terapia Combinada , Femenino , Estudios de Seguimiento , Humanos , Neoplasias Hipofaríngeas/diagnóstico por imagen , Neoplasias Hipofaríngeas/metabolismo , Neoplasias Hipofaríngeas/terapia , Neoplasias Laríngeas/diagnóstico por imagen , Neoplasias Laríngeas/metabolismo , Neoplasias Laríngeas/terapia , Masculino , Persona de Mediana Edad , Imagen Multimodal , Recurrencia Local de Neoplasia/diagnóstico por imagen , Recurrencia Local de Neoplasia/metabolismo , Recurrencia Local de Neoplasia/terapia , Pronóstico , Radiofármacos/metabolismo , Estudios Retrospectivos , Tasa de Supervivencia , Carga Tumoral
11.
Prev Med Rep ; 42: 102723, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38659997

RESUMEN

Objective: Vaccination has engendered a spectrum of public opinions, with social media acting as a crucial platform for health-related discussions. The emergence of artificial intelligence technologies, such as large language models (LLMs), offers a novel opportunity to efficiently investigate public discourses. This research assesses the accuracy of ChatGPT, a widely used and freely available service built upon an LLM, for sentiment analysis to discern different stances toward Human Papillomavirus (HPV) vaccination. Methods: Messages related to HPV vaccination were collected from social media supporting different message formats: Facebook (long format) and Twitter (short format). A selection of 1,000 human-evaluated messages was input into the LLM, which generated multiple response instances containing its classification results. Accuracy was measured for each message as the level of concurrence between human and machine decisions, ranging between 0 and 1. Results: Average accuracy was notably high when 20 response instances were used to determine the machine decision of each message: .882 (SE = .021) and .750 (SE = .029) for anti- and pro-vaccination long-form; .773 (SE = .027) and .723 (SE = .029) for anti- and pro-vaccination short-form, respectively. Using only three or even one instance did not lead to a severe decrease in accuracy. However, for long-form messages, the language model exhibited significantly lower accuracy in categorizing pro-vaccination messages than anti-vaccination ones. Conclusions: ChatGPT shows potential in analyzing public opinions on HPV vaccination using social media content. However, understanding the characteristics and limitations of a language model within specific public health contexts remains imperative.

12.
Neurology ; 102(1): e207806, 2024 Jan 09.
Artículo en Inglés | MEDLINE | ID: mdl-38165363

RESUMEN

BACKGROUND AND OBJECTIVE: We aimed to investigate the association between glycemic variability (GV) and neuroimaging markers of white matter hyperintensities (WMH), beta-amyloid (Aß), brain atrophy, and cognitive impairment. METHODS: This was a retrospective cohort study that included participants without dementia from a memory clinic. They all had Aß PET, brain MRI, and standardized neuropsychological tests and had fasting glucose (FG) levels tested more than twice during the study period. We defined GV as the intraindividual visit-to-visit variability in FG levels. Multivariable linear regression and logistic regression were used to identify whether GV was associated with the presence of severe WMH and Aß uptake with DM, mean FG levels, age, sex, hypertension, and presence of APOE4 allele as covariates. Mediation analyses were used to investigate the mediating effect of WMH and Aß uptake on the relationship between GV and brain atrophy and cognition. RESULTS: Among the 688 participants, the mean age was 72.2 years, and the proportion of female participants was 51.9%. Increase in GV was predictive of the presence of severe WMH (coefficient [95% CI] 1.032 [1.012-1.054]; p = 0.002) and increased Aß uptake (1.005 [1.001-1.008]; p = 0.007). Both WMH and increased Aß uptake partially mediated the relationship between GV and frontal-executive dysfunction (GV → WMH → frontal-executive; direct effect, -0.319 [-0.557 to -0.080]; indirect effect, -0.050 [-0.091 to -0.008]) and memory dysfunction (GV → Aß â†’ memory; direct effect, -0.182 [-0.338 to -0.026]; indirect effect, -0.067 [-0.119 to -0.015]), respectively. In addition, increased Aß uptake completely mediated the relationship between GV and hippocampal volume (indirect effect, -1.091 [-2.078 to -0.103]) and partially mediated the relationship between GV and parietal thickness (direct effect, -0.00101 [-0.00185 to -0.00016]; indirect effect, -0.00016 [-0.00032 to -0.000002]). DISCUSSION: Our findings suggest that increased GV is related to vascular and Alzheimer risk factors and neurodegenerative markers, which in turn leads to subsequent cognitive impairment. Furthermore, GV can be considered a potentially modifiable risk factor for dementia prevention.


Asunto(s)
Enfermedades del Sistema Nervioso Central , Disfunción Cognitiva , Demencia , Leucoaraiosis , Enfermedades Neurodegenerativas , Femenino , Humanos , Anciano , Estudios Retrospectivos , Disfunción Cognitiva/diagnóstico por imagen , Neuroimagen , Péptidos beta-Amiloides , Hipocampo , Atrofia
13.
Clin Nucl Med ; 49(1): 1-8, 2024 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-38048354

RESUMEN

PURPOSE: The CT-based regional direct comparison Centiloid (dcCL) method was developed to harmonize and quantify regional ß-amyloid (Aß) burden. In the present study, we aimed to investigate correlations between the CT-based regional dcCL scales and Aß pathological burdens and to validate the clinical utility using thresholds derived from pathological assessment. PATIENTS AND METHODS: We included a pathological cohort of 63 cases and a clinical cohort of 4062 participants, and obtained modified Consortium to Establish a Registry for Alzheimer's Disease criteria (mCERAD) scores by assessment of neuritic plaque burdens in multiple areas of each cortical region. PET and CT images were processed using the CT-based regional dcCL method to calculate scales in 6 distinct regions. RESULTS: The CT-based regional dcCL scales were correlated with neuritic plaque burdens represented by mCERAD scores, globally and regionally ( r = 0.56~0.76). In addition, striatum dcCL scales reflected Aß involvement in the striatum ( P < 0.001). The regional dcCL scales could predict significant Aß deposition in specific brain regions with high accuracy: area under the receiver operating characteristic curve of 0.81-0.97 with an mCERAD cutoff of 1.5 and area under the receiver operating characteristic curve of 0.88-0.93 with an mCERAD cutoff of 0.5. When applying the dcCL thresholds of 1.5 mCERAD scores, the G(-)R(+) group showed lower performances in memory and global cognitive functions and had less hippocampal volume compared with the G(-)R(-) group ( P < 0.001). However, when applying the dcCL thresholds of 0.5 mCERAD scores, there were no differences in the global cognitive functions between the 2 groups. CONCLUSIONS: The thresholds of regional dcCL scales derived from pathological assessments might provide clinicians with a better understanding of biomarker-guided diagnosis and distinguishable clinical phenotypes, which are particularly useful when harmonizing different PET ligands with only PET/CT.


Asunto(s)
Enfermedad de Alzheimer , Tomografía Computarizada por Tomografía de Emisión de Positrones , Humanos , Placa Amiloide/patología , Enfermedad de Alzheimer/diagnóstico , Amiloide/metabolismo , Péptidos beta-Amiloides/metabolismo , Encéfalo/metabolismo , Tomografía de Emisión de Positrones/métodos
14.
Heliyon ; 9(12): e22409, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38076046

RESUMEN

Background: Bone scans are often used to identify bone metastases, but their low specificity may necessitate further studies. Deep learning models may improve diagnostic accuracy but require both medical and programming expertise. Therefore, we investigated the feasibility of constructing a deep learning model employing ChatGPT for the diagnosis of bone metastasis in bone scans and to evaluate its diagnostic performance. Method: We examined 4626 consecutive cancer patients (age, 65.1 ± 11.3 years; 2334 female) who had bone scans for metastasis assessment. A nuclear medicine physician developed a deep learning model using ChatGPT 3.5 (OpenAI). We employed ResNet50 as the backbone network and compared the diagnostic performance of four strategies (original training set, original training set with 1:10 class weight, 10-fold data augmentation for positive images only, and 10-fold data augmentation for all images) to address the class imbalance. We used a class activation map algorithm for visualization. Results: Among the four strategies, the deep learning model with 10-fold data augmentation for positive cases only, using a batch size of 16 and an epoch size of 150, achieved the area under curve of 0.8156, the sensitivity of 56.0 %, and specificity of 88.7 %. The class activation map indicated that the model focused on disseminated bone metastases within the spine but might confuse them with benign spinal lesions or intense urinary activity. Conclusions: Our study illustrates that a clinical physician with rudimentary programming skills can develop a deep learning model for medical image analysis, such as diagnosing bone metastasis in bone scans using ChatGPT. Model visualization may offer guidance in enhancing deep learning model development, including preprocessing, and potentially support clinical decision-making processes.

15.
J Racial Ethn Health Disparities ; 10(1): 168-175, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-35048309

RESUMEN

Little is known about the predictors of blood pressure (BP) among African American men living with HIV. We examined whether age and body mass index (BMI) are associated with higher blood pressure (BP) and whether being married and muscular endurance are associated with lower BP among African American men living with HIV. Second, we examined whether being married moderated the effects of the other predictors on BP. Finally, we examined whether BMI mediated the relationship between muscular endurance and BP. This article is a prospective secondary analysis of data from a randomized controlled trial of a health-promotion intervention for African American men living with HIV. We measured the participants' BP pre-intervention and three, six, and 12 months post-intervention. Generalized estimating equations linear regression analyses examined whether marital status, age, BMI, and muscular endurance predicted BP post-intervention, adjusting for pre-intervention BP and the intervention. Older age, higher BMI, and lower muscular endurance predicted higher BP post-intervention, adjusting for the intervention and baseline BP. Although marital status did not predict post-intervention BP, it moderated the negative effect of higher BMI. The positive relation of BMI to BP was weaker among married men than unmarried men. Muscular endurance had an indirect impact on BP mediated through BMI. Public health efforts targeting older African American men with HIV should focus on increasing muscular endurance in this population to lower BMI as a strategy to reduce cardiovascular disease risk in this population.


Asunto(s)
Infecciones por VIH , Hipertensión , Masculino , Humanos , Presión Sanguínea/fisiología , Negro o Afroamericano , Promoción de la Salud , Infecciones por VIH/epidemiología
16.
Front Aging Neurosci ; 15: 1209027, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37771522

RESUMEN

Background and objectives: Alzheimer's disease (AD) is more prevalent in women than in men; however, there is a discrepancy in research on sex differences in AD. The human brain is a large-scale network with hub regions forming a central core, the rich-club, which is vital to cognitive functions. However, it is unknown whether alterations in the rich-clubs in AD differ between men and women. We aimed to investigate sex differences in the rich-club organization in the brains of patients with AD. Methods: In total, 260 cognitively unimpaired individuals with negative amyloid positron emission tomography (PET) scans, 281 with prodromal AD (mild cognitive impairment due to AD) and 285 with AD dementia who confirmed with positive amyloid PET scans participated in the study. We obtained high-resolution T1-weighted and diffusion tensor images and performed network analysis. Results: We observed sex differences in the rich-club and feeder connections in patients with AD, suggesting lower structural connectivity strength in women than in men. We observed a significant group-by-sex interaction in the feeder connections, particularly in the thalamus. In addition, the connectivity strength of the thalamus in the feeder connections was significantly correlated with general cognitive function in only men with prodromal AD and women with AD dementia. Conclusion: Our findings provide important evidence for sex-specific alterations in the structural brain network related to AD.

17.
Health Psychol ; 42(11): 810-821, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37883037

RESUMEN

OBJECTIVE: Black adolescents in South Africa are disproportionately affected by HIV. A cluster-randomized controlled experiment examining the effects of a sexual risk-reduction intervention successfully reduced self-reported intercourse and unprotected intercourse. Based on long-term follow-up assessments, the present research examines theoretical constructs that could potentially mediate the intervention effects and how time and gender, respectively, moderated the mediation. METHOD: The behavioral outcome was measured by asking whether participants had had any vaginal sex in the past 3 months. Mediation and moderated mediation were tested based on the 3-, 6-, 12-, 42-, and 54-month postintervention outcomes. RESULTS: Three variables through which the sexual risk-reduction intervention had a significant mediated effect on the behavioral outcome were identified: abstinence career opportunities outcome expectancy (α × ß product = -0.086, 95% asymmetric confidence interval [ACI] [-0.126, -0.047]), expected parental approval of sexual intercourse (α × ß product = -0.061, [-0.102, -0.025]), and self-efficacy to avoid sexual-risk situations (α × ß product = -0.022, [-0.049, -0.001]). The moderated mediation analysis showed that gender moderated the intervention's effects on abstinence prevention outcome expectancy (B = -0.186, SEB = 0.079, p = .019), expected parental approval of sexual intercourse (B = 0.143, SEB = 0.058, p = .013), and self-efficacy to avoid sexual-risk situations (B = -0.293, SEB = 0.112, p = .009). The moderated mediation analysis also revealed that time moderated the effects of the intervention on abstinence career opportunities outcome expectancy (B = -0.293, SEB = 0.106, p = .006), self-efficacy to avoid sexual-risk situations (B = 0.335, SEB = 0.060, p < .001), and cultural myths regarding HIV transmission (B = 0.138, SEB = 0.042, p = .001); and the association between four theoretical constructs and the behavioral outcome: abstinence career opportunities outcome expectancy (B = -0.267, SEB = 0.104, p = .001), self-efficacy to refuse sex (B = -0.132, SEB = 0.043, p = .002), self-efficacy to avoid sexual-risk situations (B = -0.093, SEB = 0.055, p = .009), and HIV risk-reduction knowledge (B = -0.286, SEB = 0.134, p = .003). CONCLUSIONS: The present study identifies theoretical constructs that mediated the intervention effects on the sexual behavior among South African adolescents for an extended period of time. The findings also reveal gender differences in psychological mechanisms initiated by a sexual risk-reduction intervention and the long-term temporal dynamics of the intervention. (PsycInfo Database Record (c) 2023 APA, all rights reserved).


Asunto(s)
Infecciones por VIH , Femenino , Humanos , Adolescente , Sudáfrica , Infecciones por VIH/prevención & control , Promoción de la Salud , Conducta Sexual/psicología , Conducta de Reducción del Riesgo
18.
Alzheimers Res Ther ; 15(1): 197, 2023 11 10.
Artículo en Inglés | MEDLINE | ID: mdl-37950256

RESUMEN

BACKGROUND: Cholesterol plays important roles in ß-amyloid (Aß) metabolism and atherosclerosis. However, the relationships of plasma cholesterol levels with Aß and cerebral small vessel disease (CSVD) burdens are not fully understood in Asians. Herein, we investigated the relationships between plasma cholesterol profile components and Aß and CSVD burdens in a large, non-demented Korean cohort. METHODS: We enrolled 1,175 non-demented participants (456 with unimpaired cognition [CU] and 719 with mild cognitive impairment [MCI]) aged ≥ 45 years who underwent Aß PET at the Samsung Medical Center in Korea. We performed linear regression analyses with each cholesterol (low-density lipoprotein cholesterol [LDL-c], high-density lipoprotein cholesterol [HDL-c], and triglyceride) level as a predictor and each image marker (Aß uptake on PET, white matter hyperintensity [WMH] volume, and hippocampal volume) as an outcome after controlling for potential confounders. RESULTS: Increased LDL-c levels (ß = 0.014 to 0.115, p = 0.013) were associated with greater Aß uptake, independent of the APOE e4 allele genotype and lipid-lowering medication. Decreased HDL-c levels (ß = - 0.133 to - 0.006, p = 0.032) were predictive of higher WMH volumes. Increased LDL-c levels were also associated with decreased hippocampal volume (direct effect ß = - 0.053, p = 0.040), which was partially mediated by Aß uptake (indirect effect ß = - 0.018, p = 0.006). CONCLUSIONS: Our findings highlight that increased LDL-c and decreased HDL-c levels are important risk factors for Aß and CSVD burdens, respectively. Furthermore, considering that plasma cholesterol profile components are potentially modified by diet, exercise, and pharmacological agents, our results provide evidence that regulating LDL-c and HDL-c levels is a potential strategy to prevent dementia.


Asunto(s)
Enfermedades de los Pequeños Vasos Cerebrales , Disfunción Cognitiva , Humanos , LDL-Colesterol , Disfunción Cognitiva/diagnóstico por imagen , Cognición , Colesterol , Péptidos beta-Amiloides/metabolismo , Amiloide
19.
Am J Mens Health ; 16(6): 15579883221130664, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36484304

RESUMEN

People living with HIV on antiretroviral therapy have an increased risk of developing metabolic disturbances and central adiposity. Adequate engagement in physical activity (PA) could reduce the risk of chronic diseases associated with central adiposity. We conducted a secondary analysis of data from a randomized controlled trial of a PA intervention with 302 African American men aged 40 or older (53.9±7.2 years) living with HIV to assess whether the intervention reduced the waist-to-hip ratio (WHR). Generalized estimating equation analyses tested whether the PA intervention reduced WHR compared with the control group and whether age moderated its effect, adjusting for follow-up assessment time (3, 6, and 12 months postintervention) and baseline WHR and age. The analysis revealed that the intervention's effect on WHR was not significant (B = -0.008, p = .097). However, a significant interaction between age and the intervention (B = 0.001, p = .046) indicated that the intervention's effect in reducing WHR waned with increasing age. For instance, when dividing participants into three age subgroups, the intervention reduced WHR for men ages 40 to 50 (B = -0.020, p = .013) and ages 50 and 60 (B = -0.007, p = .315) but increased it among those older than 60 (B = 0.013, p = .252). The intervention's effects on WHR differed by participants' age, suggesting that different PA strategies may be needed based on age to improve the metabolic profile and reduce chronic disease risk in African American men living with HIV.


Asunto(s)
Negro o Afroamericano , Infecciones por VIH , Humanos , Relación Cintura-Cadera , Ejercicio Físico , Infecciones por VIH/tratamiento farmacológico
20.
Front Aging Neurosci ; 14: 829202, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35197846

RESUMEN

PURPOSE: Previously, sex and apolipoprotein E (APOE) genotype had distinct effects on the cognitive trajectory across the Alzheimer's disease (AD) continuum. We therefore aimed to investigate whether these trajectory curves including ß-amyloid (Aß) accumulation in the cortex and striatum, and tau accumulation would differ according to sex and APOE genotype. METHODS: We obtained 534 subjects for 18F-florbetapir (AV45) PET analysis and 163 subjects for 18F-flortaucipir (AV1451) PET analysis from the Alzheimer's Disease Neuroimaging Initiative database. For cortical Aß, striatal Aß, and tau SUVR, we fitted penalized splines to model the slopes of SUVR value as a non-linear function of baseline SUVR value. By integrating the fitted splines, we obtained the predicted SUVR curves as a function of time. RESULTS: The time from initial SUVR to the cutoff values were 14.9 years for cortical Aß, 18.2 years for striatal Aß, and 22.7 years for tau. Although there was no difference in cortical Aß accumulation rate between women and men, striatal Aß accumulation was found to be faster in women than in men, and this temporal difference according to sex was more pronounced in tau accumulation. However, APOE ε4 carriers showed faster progression than non-carriers regardless of kinds of AD biomarkers' trajectories. CONCLUSION: Our temporal trajectory models illustrate that there is a distinct progression pattern of AD biomarkers depending on sex and APOE genotype. In this regard, our models will be able to contribute to designing personalized treatment and prevention strategies for AD in clinical practice.

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