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1.
Heliyon ; 10(4): e25845, 2024 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-38384560

RESUMO

Purpose: Timely diagnosis of diabetic retinopathy is important in preventing vision loss. This study aims to determine if remote retinal imaging enables earlier eye care access among newly-diagnosed diabetic patients. Design: Retrospective cohort study. Methods: Using the OptumLabs® Data Warehouse - a longitudinal, real-world dataset containing deidentified administrative claims and electronic health record (EHR) data, we included 968 846 adults with newly diagnosed type 2 diabetes and at least 1 year of continuous enrollment. We compared time from initial diabetes diagnosis to first eye exam by remote screening or in-person eye exam. Results: We found that at year 1 after diagnosis, 5459 (0.56%) patients underwent remote imaging and 208 023 (21.5%) underwent in-person exam. The mean (95% CI) time to eye exam was 3.48 (3.38-3.58) months for remote imaging and 4.22 (4.20-4.23) months for in-person visits (p < 0.0001). Interestingly, 27.5% of remote screenings were performed on the same day of diabetes diagnosis. Excluding same-day encounters, mean time to eye exam was 4.80 (4.68-4.91) months for remote imaging and 4.85 (4.83-4.86) months for in-person eyecare (p = 0.4). Conclusions: Thus, teleophthalmology may enable earlier eye care access among patients with newly-diagnosed diabetes, primarily with same-day screenings. Increased adoption of teleretinal screening may enable earlier detection of diabetic retinopathy and prevent vision loss.

2.
Telemed J E Health ; 29(1): 81-86, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-35612464

RESUMO

Introduction: Lower insurance reimbursements have limited the financial sustainability of remote eye screening programs. Greater utilization and insurance coverage for teleophthalmology screening during the coronavirus disease 2019 (COVID-19) pandemic in 2020 may enhance awareness and expand remote retinal imaging services. This retrospective cross-sectional study evaluates utilization and insurance coverage for remote retinal imaging in the United States in 2020. Methods: We analyzed teleretinal imaging utilization and insurance payments from January 1 to December 31, 2020, using the Optum Labs Data Warehouse, a comprehensive national database of deidentified administrative claims for commercial and Medicare Advantage enrollees in the United States. We evaluated frequency of claims and insurance payment for services using the Current Procedural Terminology codes 92227 and 92228 for remote eye imaging by any provider, and 92250 for fundus photography by non-eye care providers. Results: The use of remote retinal imaging in the United States declined rapidly during the initial COVID-19 lockdown from 3,627 claims in February 2020 to 1,414 claims in April 2020, but returned to 3,133 claims by December 2020, similar to mean prepandemic levels in 2019 (2,841 ± 174.8 claims). The proportion of insurance payments for remote imaging increased temporarily from 47.4% in February to 56.7% in April, and then returned to 45.9% in December of 2020. Discussion: Utilization of remote retinal imaging declined steeply, while the insurance coverage increased during the initial COVID-19 lockdown in 2020, but returned to prepandemic levels by end of the year. Changes in utilization and relaxed restrictions on insurance reimbursements for teleophthalmology during the COVID-19 pandemic were not sustained.


Assuntos
COVID-19 , Oftalmologia , Telemedicina , Idoso , Humanos , Estados Unidos , COVID-19/epidemiologia , Pandemias , Oftalmologia/métodos , Estudos Retrospectivos , Estudos Transversais , Medicare , Controle de Doenças Transmissíveis
3.
J Am Assoc Lab Anim Sci ; 61(3): 226-233, 2022 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-35512995

RESUMO

Providing effective contraception for nonhuman primates (NHP) is challenging. Deslorelin acetate is a commercially available gonadotropin-releasing hormone (GnRH) agonist that may provide a relatively noninvasive, long-lasting, and potentially reversible alternative to standard NHP contraception methods. This study evaluated the duration of suppression of progesterone and estradiol in 6 adult female rhesus macaques (Macaca mulatta) that received a single subcutaneous 4.7 mg deslorelin implant. We hypothesized that deslorelin would suppress production of these hormones for 6 mo with a correspond- ing cessation of menses. Prior to implantation, blood was collected over 1 mo for baseline hormone analyses. Macaques were sedated at the onset of the next menstrual cycle and a 4.7 mg deslorelin implant was placed in the interscapular region. Blood was collected over the subsequent month at the same intervals used for the baseline collection schedule, and then every 7 d thereafter. Results showed that estradiol and progesterone transiently increased 1 to 3 d after implantation, then fell to basal levels within 6 d of implantation. The duration of hormone suppression (progesterone <0.5 ng/mL) varied among animals. Two macaques returned to cyclicity by 96 d and 113 d after implantation, while hormones remained suppressed in the other 4 macaques at 6 mo after implantation. Cessation of menses correlated with hormone suppression except in 1 animal that continued to have sporadic vaginal bleeding despite progesterone remaining below 0.5 ng/mL. This study indicates that deslorelin is a noninvasive and long-lasting contraceptive method in female rhesus macaques. However, individual variation should be considered when determining reimplantation intervals.


Assuntos
Hormônio Liberador de Gonadotropina , Progesterona , Animais , Implantes de Medicamento , Estradiol , Feminino , Macaca mulatta , Pamoato de Triptorrelina/análogos & derivados
4.
Cancer Causes Control ; 33(5): 711-726, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35107724

RESUMO

PURPOSE: The Risk of Pediatric and Adolescent Cancer Associated with Medical Imaging (RIC) Study is quantifying the association between cumulative radiation exposure from fetal and/or childhood medical imaging and subsequent cancer risk. This manuscript describes the study cohorts and research methods. METHODS: The RIC Study is a longitudinal study of children in two retrospective cohorts from 6 U.S. healthcare systems and from Ontario, Canada over the period 1995-2017. The fetal-exposure cohort includes children whose mothers were enrolled in the healthcare system during their entire pregnancy and followed to age 20. The childhood-exposure cohort includes children born into the system and followed while continuously enrolled. Imaging utilization was determined using administrative data. Computed tomography (CT) parameters were collected to estimate individualized patient organ dosimetry. Organ dose libraries for average exposures were constructed for radiography, fluoroscopy, and angiography, while diagnostic radiopharmaceutical biokinetic models were applied to estimate organ doses received in nuclear medicine procedures. Cancers were ascertained from local and state/provincial cancer registry linkages. RESULTS: The fetal-exposure cohort includes 3,474,000 children among whom 6,606 cancers (2394 leukemias) were diagnosed over 37,659,582 person-years; 0.5% had in utero exposure to CT, 4.0% radiography, 0.5% fluoroscopy, 0.04% angiography, 0.2% nuclear medicine. The childhood-exposure cohort includes 3,724,632 children in whom 6,358 cancers (2,372 leukemias) were diagnosed over 36,190,027 person-years; 5.9% were exposed to CT, 61.1% radiography, 6.0% fluoroscopy, 0.4% angiography, 1.5% nuclear medicine. CONCLUSION: The RIC Study is poised to be the largest study addressing risk of childhood and adolescent cancer associated with ionizing radiation from medical imaging, estimated with individualized patient organ dosimetry.


Assuntos
Leucemia , Adolescente , Adulto , Criança , Feminino , Humanos , Estudos Longitudinais , Ontário/epidemiologia , Gravidez , Radiografia , Estudos Retrospectivos , Adulto Jovem
5.
J Neuroophthalmol ; 42(1): 73-78, 2022 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-33870951

RESUMO

BACKGROUND: Optical coherence tomography angiography (OCTA) is a new noninvasive imaging modality that provides high resolution images of the optic nerve head and peripapillary retinal capillary vasculature which can be affected by optic nerve or retinal pathologies. High repeatability of peripapillary capillary density measurement using OCTA has been demonstrated in normal eyes and eyes with glaucoma. The purpose of our study was to quantify the repeatability of peripapillary capillary density measurement using OCTA in both normal eyes and eyes with optic atrophy, optic disc edema, and retinal vasculopathy. METHODS: This prospective cross-sectional study enrolled 31 patients (59 eyes) including 16 eyes with optic nerve pathology (7 with disc edema from papilledema and 9 with optic atrophy), 35 eyes with retinal vascular disease, and 8 normal eyes. All eyes were imaged twice (30 minutes apart) with the Optovue AngioVue OCTA instrument to obtain 4.5 × 4.5 mm peripapillary scans. Scans were considered good quality if signal strength was 6 or greater. The OCTA parameters obtained include the radial peripapillary capillary (RPC) density of the whole disc, inside the disc, peripapillary region, and the 4 quadrants of the disc (superior, nasal, inferior, and temporal). A Student's t test was used to compare means. Intraclass correlation coefficient (ICC) was calculated to measure repeatability. RESULTS: Repeatability of RPC density measurements for all regions analyzed demonstrated good to excellent repeatability for the whole cohort {ICC for the whole image was 0.915 (95% confidence interval [CI] = 0.855-0.951)}; ICC for the peripapillary region was 0.945 (95% CI = 0.905-0.969). In the subset of eyes with good image quality (i.e., signal strength ≥ 6), ICC was slightly higher for all regions, with excellent repeatability of the peripapillary region (ICC was 0.971 [95% CI = 0.943-0.986]). Conversely, for eyes with poor image quality scans (i.e., signal strength < 6), ICC was lower, corresponding to moderate to good repeatability for most parameters. For the subset of eyes with optic atrophy, disc edema from papilledema or retinal vasculopathy, all had good to excellent repeatability of the vessel density of the entire disc (ICC values were 0.954 [95% CI = 0.804-0.990], 0.921 [95% CI = 0.711-0.982], and 0.895 [95% CI = 0.788-0.951, respectively]) and of the peripapillary region (ICC values were 0.980 [95% CI = 0.904-0.996], 0.966 [95% CI = 0.854-0.993], and 0.916 [95% CI = 0.827-0.961], respectively). CONCLUSIONS: The peripapillary capillary density measurement obtained using a commercial OCTA instrument is highly repeatable in eyes with optic nerve atrophy, disc edema from papilledema, or retinal vasculopathy.


Assuntos
Atrofia Óptica , Disco Óptico , Papiledema , Estudos Transversais , Angiofluoresceinografia/métodos , Humanos , Disco Óptico/irrigação sanguínea , Estudos Prospectivos , Vasos Retinianos/diagnóstico por imagem , Vasos Retinianos/patologia , Tomografia de Coerência Óptica/métodos
8.
Cancer ; 121(17): 2951-9, 2015 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-25946376

RESUMO

BACKGROUND: Ethnic minorities, especially African Americans and Latinos, bear a disproportionate burden of colorectal cancer (CRC), as reflected in incidence, cancer stage, and mortality statistics. In all ethnic groups, first-degree relatives (FDRs) of CRC cases are at an elevated disease risk. However, underuse of CRC screening persists and is particularly evident among minority groups. The current study tested a stepped intervention to increase CRC screening among an ethnically diverse sample of FDRs of CRC cases. METHODS: A statewide cancer registry was used to recruit CRC cases and through them their FDRs. Relatives who were not current on CRC screening were randomized to intervention or usual-care control arms. The stepped intervention consisted of ethnically targeted and individually tailored print materials followed by telephone counseling for those unscreened at 6 months. RESULTS: The study sample of 1280 individuals consisted of 403 Latino, 284 African American, 242 Asian, and 351 white FDRs. Statistically significant effects were observed for the cumulative print plus telephone intervention at 12 months (26% in the intervention vs 18% in the control group) and the print intervention alone at 6 months (15% in the intervention vs 10% in the control group). The effect of the print intervention alone versus the cumulative interventions was not statistically significantly different. Stratified analyses indicated that the intervention was effective among white, Latino, and Asian individuals, but not among African-Americans. CONCLUSIONS: Overall, the intervention was effective in increasing screening rates. Oversampling racial/ethnic minorities allowed for the examination of effects within subgroups, revealing no effect among African American individuals. This finding illustrates the importance of including sufficient numbers of participants from diverse ethnic subgroups in intervention research to enable such stratified analyses.


Assuntos
Neoplasias Colorretais/diagnóstico , Detecção Precoce de Câncer/estatística & dados numéricos , Adulto , Negro ou Afro-Americano , Idoso , Asiático , Feminino , Hispânico ou Latino , Humanos , Masculino , Pessoa de Meia-Idade
9.
J Stat Comput Simul ; 85(15): 3108-3128, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-28670022

RESUMO

For a normal model with a conjugate prior, we provide an in depth examination of the effects of the hyperparameters on the long-run frequentist properties of posterior point and interval estimates. Under an assumed sampling model for the data generating mechanism, we examine how hyperparameter values affect the mean squared error (MSE) of posterior means and the true coverage of credible intervals. We develop two types of hyperparameter optimality. MSE optimal hyperparameters minimize the MSE of posterior point estimates. Credible interval optimal hyperparameters result in credible intervals that have minimum length while still retaining nominal coverage. A poor choice of hyperparameters has a worse consequence on the credible interval coverage than on the MSE of posterior point estimates. We give an example to demonstrate how our results can be used to evaluate the potential consequences of hyperparameter choices.

10.
Stat Med ; 28(13): 1821-40, 2009 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-19387975

RESUMO

An alternative to analysis of variance is a model selection approach where every partition of the treatment means into clusters with equal value is treated as a separate model. The null hypothesis that all treatments are equal corresponds to the partition with all means in a single cluster. The alternative hypothesis correspond to the set of all other partitions of treatment means. A model selection approach can also be used for a treatment by covariate interaction, where the null hypothesis and each alternative correspond to a partition of treatments into clusters with equal covariate effects. We extend the partition-as-model approach to simultaneous inference for both treatment main effect and treatment interaction with a continuous covariate with separate partitions for the intercepts and treatment-specific slopes. The model space is the Cartesian product of the intercept partition and the slope partition, and we develop five joint priors for this model space. In four of these priors the intercept and slope partition are dependent. We advise on setting priors over models, and we use the model to analyze an orthodontic data set that compares the frictional resistance created by orthodontic fixtures.


Assuntos
Análise de Variância , Modelos Estatísticos , Teorema de Bayes , Biometria , Análise por Conglomerados , Metodologias Computacionais , Bases de Dados Factuais , Humanos , Ortodontia/estatística & dados numéricos , Resultado do Tratamento
11.
Am J Orthopsychiatry ; 79(1): 51-9, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19290725

RESUMO

The impact of parental substance use on the emotional and behavioral adjustment of their adolescent children was examined over 5 years. A representative sample of 220 parents with HIV (PWH) and 330 adolescent children in New York City were repeatedly assessed. Some parents never used marijuana or hard drugs over the 5 years (nonusers). Among those who were users, substance use varied over time. PWH who used substances during a specific 3-month period were classified as active users and those who abstained from substance use were classified as inactive users. Longitudinal regression analyses were used to analyze the impact of variations in patterns of substance use over time on their adolescent children's emotional adjustment and behavioral problems. PWH relapse exacerbated adolescent substance use, trouble with peers, and adolescent emotional distress. Even time-limited reductions in parents' substance abuse can have a significant positive impact on their adolescent children's emotional and behavioral adjustment. Interventions that address parental substance use among PWH should be developed to ameliorate the impact of substance use relapse on their adolescents.


Assuntos
Síndrome da Imunodeficiência Adquirida/complicações , Comportamento do Adolescente/psicologia , Relações Pais-Filho , Transtornos Relacionados ao Uso de Substâncias/complicações , Adaptação Psicológica , Adolescente , Adulto , Sintomas Afetivos , Transtornos do Comportamento Infantil , Terapia Cognitivo-Comportamental , Feminino , Humanos , Estudos Longitudinais , Masculino , Transtornos Relacionados ao Uso de Substâncias/terapia , Fatores de Tempo
12.
Chem Res Toxicol ; 22(5): 863-74, 2009 May.
Artigo em Inglês | MEDLINE | ID: mdl-19326901

RESUMO

4-Hydroxy-2(E)-nonenal (HNE), a reactive aldehyde derived from oxidized lipids, has been implicated in the pathogenesis of cardiovascular and neurological diseases, in part by its ability to induce oxidative stress and by protein carbonylation in target cells. The effects of intracellular ascorbic acid (vitamin C) on HNE-induced cytotoxicity and protein carbonylation were investigated in human THP-1 monocytic leukemia cells. HNE treatment of these cells resulted in apoptosis, necrosis, and protein carbonylation. Ascorbic acid accumulated in the cells at concentrations of 6.4 or 8.9 mM after treatment with 0.1 or 1 mM ascorbate in the medium for 18 h. Pretreatment of cells with 1.0 mM ascorbate decreased HNE-induced formation of reactive oxygen species and formation of protein carbonyls. The protective effects of ascorbate were associated with an increase in the formation of GSH-HNE conjugate and its phase 1 metabolites, measured by LC-MS/MS, and with increased transport of GSH conjugates from the cells into the medium. Ascorbate pretreatment enhanced the efflux of the multidrug resistant protein (MRP) substrate, carboxy-2',7'-dichlorofluorescein (CDF), and it prevented the HNE-induced inhibition of CDF export from THP-1 cells, suggesting that the protective effect of ascorbate against HNE cytotoxicity is through modulation of MRP-mediated transport of GSH-HNE conjugate metabolites. The formation of ascorbate adducts of HNE was observed in the cell exposure experiments, but it represented a minor pathway contributing to the elimination of HNE and to the protective effects of ascorbate.


Assuntos
Aldeídos/toxicidade , Ácido Ascórbico/metabolismo , Aldeídos/farmacologia , Apoptose , Transporte Biológico , Caspase 3/metabolismo , Fluoresceínas/metabolismo , Glutationa/metabolismo , Humanos , Inativação Metabólica , Leucemia , Carbonilação Proteica , Células Tumorais Cultivadas
13.
J Agric Food Chem ; 57(5): 1821-6, 2009 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-19170637

RESUMO

Meadowfoam ( Limnanthes alba ) is an oilseed crop grown in western Oregon. After extraction of the oil from the seeds, the remaining seed meal contains 2-4% of the glucosinolate glucolimnanthin. This study investigated the effect of fermentation of seed meal on its chemical composition and the effect of the altered composition on downy brome ( Bromus tectorum ) coleoptile emergence. Incubation of enzyme-inactive seed meal with enzyme-active seeds (1% by weight) resulted in complete degradation of glucolimnanthin and formation of 3-methoxybenzyl isothiocyanate in 28% yield. Fermentation in the presence of an aqueous solution of FeSO(4) (10 mM) resulted in the formation of 3-methoxyphenylacetonitrile and 2-(3-methoxyphenyl)ethanethioamide, a novel natural product. The formation of the isothiocyanate, the nitrile, and the thioamide, as a total, correlated with an increase of herbicidal potency of the seed meal (r(2) = 0.96). The results of this study open new possibilities for the refinement of glucosinolate-containing seed meals for use as bioherbicides.


Assuntos
Fermentação , Herbicidas/metabolismo , Magnoliopsida/metabolismo , Tiocianatos/metabolismo , Tioglucosídeos/metabolismo , Bromus/efeitos dos fármacos , Herbicidas/química , Herbicidas/farmacologia , Magnoliopsida/química , Sementes/química , Sementes/metabolismo , Tiocianatos/química , Tiocianatos/farmacologia , Tioglucosídeos/química , Tioglucosídeos/farmacologia
14.
J Stat Plan Inference ; 139(12): 4111-4122, 2009 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-25554718

RESUMO

A challenge for implementing performance based Bayesian sample size determination is selecting which of several methods to use. We compare three Bayesian sample size criteria: the average coverage criterion (ACC) which controls the coverage rate of fixed length credible intervals over the predictive distribution of the data, the average length criterion (ALC) which controls the length of credible intervals with a fixed coverage rate, and the worst outcome criterion (WOC) which ensures the desired coverage rate and interval length over all (or a subset of) possible datasets. For most models, the WOC produces the largest sample size among the three criteria, and sample sizes obtained by the ACC and the ALC are not the same. For Bayesian sample size determination for normal means and differences between normal means, we investigate, for the first time, the direction and magnitude of differences between the ACC and ALC sample sizes. For fixed hyperparameter values, we show that the difference of the ACC and ALC sample size depends on the nominal coverage, and not on the nominal interval length. There exists a threshold value of the nominal coverage level such that below the threshold the ALC sample size is larger than the ACC sample size, and above the threshold the ACC sample size is larger. Furthermore, the ACC sample size is more sensitive to changes in the nominal coverage. We also show that for fixed hyperparameter values, there exists an asymptotic constant ratio between the WOC sample size and the ALC (ACC) sample size. Simulation studies are conducted to show that similar relationships among the ACC, ALC, and WOC may hold for estimating binomial proportions. We provide a heuristic argument that the results can be generalized to a larger class of models.

15.
J Consult Clin Psychol ; 73(2): 221-8, 2005 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-15796629

RESUMO

The impact of HIV-related parental death on 414 adolescents was examined over a period of 6 years. The adjustment of bereaved adolescents was compared over 4 time periods relative to parental death and was also compared with the adjustment of nonbereaved adolescents. Bereaved adolescents had significantly more emotional distress, negative life events, and contact with the criminal justice system than nonbereaved youths; these behaviors did not remain significantly higher after parental death. Depressive symptoms and passive problem solving increased soon after parental death, as compared with nonbereaved adolescents. One year subsequent to parental death, depression and passive problem solving were similar to the levels of nonbereaved peers. Only sexual risk behaviors increased following parental death. These results suggest the importance of early family intervention soon after parental HIV diagnosis, prior to parental death, and sustained over time.


Assuntos
Adaptação Psicológica , Atitude Frente a Morte , Luto , Soropositividade para HIV , Pais , Adolescente , Criança , Feminino , Seguimentos , Humanos , Acontecimentos que Mudam a Vida , Masculino , Fatores de Tempo
16.
J Nutr ; 133(11 Suppl 2): 3965S-3971S, 2003 11.
Artigo em Inglês | MEDLINE | ID: mdl-14672297

RESUMO

Previous observational studies in developing countries have suggested that diet quality, particularly increased animal source food (ASF) consumption, is positively associated with child cognitive development. This report presents findings from a study in rural Kenya, designed to test the impact of three different diets on the cognitive development of school children. Twelve schools with a total of 555 Standard 1 children (equivalent to U.S. Grade 1) were randomized to one of four feeding interventions: Meat, Milk, Energy or Control (no feeding). Feeding continued for seven school terms (21 mo), and cognitive tests were administered before the commencement of feeding and during every other term of feeding. Hierarchical linear random effects models and associated methods were used to examine the effects of treatment group on changes in cognitive performance over time. Analyses revealed that children receiving supplemental food with meat significantly outperformed all other children on the Raven's Progressive Matrices. Children supplemented with meat, and children supplemented with energy, outperformed children in the Control group on tests of arithmetic ability. There were no group differences on tests of verbal comprehension. Results suggest that supplementation with animal source food has positive effects on Kenyan children's cognitive performance. However, these effects are not equivalent across all domains of cognitive functioning, nor did different forms of animal source foods produce the same beneficial effects. Implications of these findings for supplementation programs in developing countries are discussed.


Assuntos
Cognição/fisiologia , Dieta/normas , Suplementos Nutricionais , Animais , Criança , Países em Desenvolvimento , Humanos , Quênia , Carne , População Rural
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