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1.
Brain ; 145(7): 2518-2527, 2022 07 29.
Artículo en Inglés | MEDLINE | ID: mdl-35094057

RESUMEN

Cancer and Alzheimer's disease are common diseases in ageing populations. Previous research has reported a lower incidence of Alzheimer's disease-type (amnestic) dementia among individuals with a diagnosis of cancer. Both cancer and amnestic dementia are prevalent and potentially lethal clinical syndromes. The current study was conducted to investigate the association of cancer diagnosis with neuropathological and cognitive features of dementia. Data were analysed from longitudinally evaluated participants in a community-based cohort study of brain ageing who came to autopsy at the University of Kentucky Alzheimer's Disease Research Center. These data were linked to the Kentucky Cancer Registry, a population-based state cancer surveillance system, to obtain cancer-related data. We examined the relationship between cancer diagnosis, clinical dementia diagnosis, Mini-Mental State Examination scores and neuropathological features using inverse probability weighting to address bias due to confounding and missing data. To address bias due to inclusion of participants with dementia at cohort baseline, we repeated all analyses restricted to the participants who were cognitively normal at baseline. Included participants (n = 785) had a mean ± standard deviation age of death of 83.8 ± 8.6 years; 60.1% were female. Cancer diagnosis was determined in 190 (24.2%) participants, and a diagnosis of mild cognitive impairment or dementia was determined in 539 (68.7%). APOE ɛ4 allele dosage was lower among participants with cancer diagnosis compared to cancer-free participants overall (P = 0.0072); however, this association was not observed among those who were cognitively normal at baseline. Participants with cancer diagnosis had lower odds of mild cognitive impairment or dementia, and higher cognitive test scores (e.g. Mini-Mental State Examination scores evaluated 6 and ≤2 years ante-mortem, P < 0.001 for both comparisons). Cancer diagnosis also associated with lower odds of higher Braak neurofibrillary tangle stages (III/IV) or (V/VI), moderate/frequent neuritic plaques, moderate/frequent diffuse plaques and moderate/severe cerebral amyloid angiopathy (all P < 0.05). By contrast, TDP-43, α-synuclein and cerebrovascular pathologies were not associated with cancer diagnosis. Cancer diagnosis was associated with a lower burden of Alzheimer's disease pathology and less cognitive impairment. These findings from a community-based cohort with neuropathological confirmation of substrates support the hypothesis that there is an inverse relationship between cancer and Alzheimer's disease.


Asunto(s)
Enfermedad de Alzheimer , Neoplasias , Anciano , Anciano de 80 o más Años , Enfermedad de Alzheimer/diagnóstico , Enfermedad de Alzheimer/epidemiología , Enfermedad de Alzheimer/genética , Estudios de Cohortes , Femenino , Humanos , Masculino , Neoplasias/diagnóstico , Neoplasias/epidemiología , Neoplasias/genética , Ovillos Neurofibrilares/patología , Neuropatología , Placa Amiloide/patología
2.
Lifetime Data Anal ; 29(4): 752-768, 2023 10.
Artículo en Inglés | MEDLINE | ID: mdl-37210470

RESUMEN

The Nun study is a well-known longitudinal epidemiology study of aging and dementia that recruited elderly nuns who were not yet diagnosed with dementia (i.e., incident cohort) and who had dementia prior to entry (i.e., prevalent cohort). In such a natural history of disease study, multistate modeling of the combined data from both incident and prevalent cohorts is desirable to improve the efficiency of inference. While important, the multistate modeling approaches for the combined data have been scarcely used in practice because prevalent samples do not provide the exact date of disease onset and do not represent the target population due to left-truncation. In this paper, we demonstrate how to adequately combine both incident and prevalent cohorts to examine risk factors for every possible transition in studying the natural history of dementia. We adapt a four-state nonhomogeneous Markov model to characterize all transitions between different clinical stages, including plausible reversible transitions. The estimating procedure using the combined data leads to efficiency gains for every transition compared to those from the incident cohort data only.


Asunto(s)
Demencia , Monjas , Humanos , Anciano , Estudios Longitudinales , Factores de Riesgo , Demencia/epidemiología
3.
Am J Occup Ther ; 77(4)2023 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-37624998

RESUMEN

IMPORTANCE: Supporting community residency of adults with Alzheimer's disease (AD) is a critical public health initiative. Occupational therapy can contribute to this goal. OBJECTIVE: To assess the feasibility of a novel telehealth intervention to support occupational engagement in community-residing people with AD. DESIGN: Single-blind, three-arm, parallel, randomized controlled trial. SETTING: Occupational therapy delivered through telehealth in participants' homes. PARTICIPANTS: People with AD who reside in the community with behavioral symptoms and their care partners (dyads). INTERVENTIONS: (1) HARMONY (Helping older Adults cReate & Manage OccupatioNs successfully), a telehealth intervention that applies principles of individualized guided discovery with environmental cueing for caregivers of persons with AD to promote activity participation and manage behavioral symptoms; (2) standardized training regarding the use of a sensory-based approach in dementia care; and (3) a control, including home safety education and weekly monitoring of behaviors. OUTCOMES AND MEASURES: Feasibility was assessed as the primary outcome measured by completion of at least 75% of the telehealth sessions. Secondary outcomes included change in functional activity performance and neuropsychiatric behavioral symptoms. RESULTS: Twenty-eight dyads participated. The intervention was feasible, with high adherence to weekly visits (M number of visits = 5.4 for HARMONY, 4.9 for standardized training, and 4.6 for control), with high participant retention in the intervention arms. HARMONY demonstrated promise in improving patient performance and behavioral symptoms. CONCLUSIONS AND RELEVANCE: HARMONY is feasibly delivered through telehealth service and has a positive effect on occupational performance and behavioral symptoms of AD. Additional studies are needed to explore effectiveness in a broader population. What This Article Adds: Use of HARMONY for community-residing adults with AD is feasible and has promise for improving functional activity performance and behavioral symptoms, as well as caregiver satisfaction.


Asunto(s)
Enfermedad de Alzheimer , Terapia Ocupacional , Telemedicina , Humanos , Anciano , Estudios de Factibilidad , Método Simple Ciego , Síntomas Conductuales
4.
Stat Neerl ; 77(3): 304-321, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-39309275

RESUMEN

Finite Markov chains with absorbing states are popular tools for analyzing longitudinal data with categorical responses. The one step transition probabilities can be defined in terms of fixed and random effects but it is difficult to estimate these effects due to many unknown parameters. In this article we propose a three-step estimation method. In the first step the fixed effects are estimated by using a marginal likelihood function, in the second step the random effects are estimated after substituting the estimated fixed effects into a joint likelihood function defined as a h-likelihood, and in the third step the covariance matrix for the vector of random effects is estimated using the Hessian matrix for this likelihood function. An application involving an analysis of longitudinal cognitive data is used to illustrate the method.

5.
BMC Cancer ; 22(1): 844, 2022 Aug 03.
Artículo en Inglés | MEDLINE | ID: mdl-35922758

RESUMEN

Glioblastoma (GBM) is one of the deadliest cancers. Treatment options are limited, and median patient survival is only several months. Translation of new therapies is hindered by a lack of GBM models that fully recapitulate disease heterogeneity. Here, we characterize two human GBM models (U87-luc2, U251-RedFLuc). In vitro, both cell lines express similar levels of luciferase and show comparable sensitivity to temozolomide and lapatinib exposure. In vivo, however, the two GBM models recapitulate different aspects of the disease. U87-luc2 cells quickly grow into large, well-demarcated tumors; U251-RedFLuc cells form small, highly invasive tumors. Using a new method to assess GBM invasiveness based on detecting tumor-specific anti-luciferase staining in brain slices, we found that U251-RedFLuc cells are more invasive than U87-luc2 cells. Lastly, we determined expression levels of ABC transporters in both models. Our findings indicate that U87-luc2 and U251-RedFLuc GBM models recapitulate different aspects of GBM heterogeneity that need to be considered in preclinical research.


Asunto(s)
Neoplasias Encefálicas , Glioblastoma , Neoplasias Encefálicas/tratamiento farmacológico , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/metabolismo , Línea Celular Tumoral , Proliferación Celular , Glioblastoma/tratamiento farmacológico , Glioblastoma/genética , Glioblastoma/metabolismo , Humanos , Temozolomida/farmacología , Temozolomida/uso terapéutico
6.
Stat Med ; 40(11): 2650-2664, 2021 05 20.
Artículo en Inglés | MEDLINE | ID: mdl-33694178

RESUMEN

Finite Markov chains are useful tools for studying transitions among health states; these chains can be complex consisting of a mix of transient and absorbing states. The transition probabilities, which are often affected by covariates, can be difficult to estimate due to the presence of many covariates and/or a subset of transitions that are rarely observed. The purpose of this article is to show how to estimate the effect of a subset of covariates of interest after adjusting for the presence of multiple other covariates by applying multidimensional dimension reduction to the latter. The case in which transitions within each row of the one-step transition probability matrix are estimated by multinomial logistic regression is discussed in detail. Dimension reduction for the adjustment covariates involves estimating the effect of the covariates by a product of matrices iteratively; at each iteration one matrix in the product is fixed while the second is estimated using either standard software or nonlinear estimation, depending on which of the matrices in the product is fixed. The algorithm is illustrated by an application where the effect of at least one Apolipoprotein-E (APOE) gene ϵ4 allele on transition probability is estimated in a Markov Chain that includes adjustment for eight covariates and focuses on transitions from normal cognition to several forms of mild cognitive impairment, with possible absorption into dementia. Data were drawn from annual cognitive assessments of 649 participants enrolled in the BRAiNS cohort at the University of Kentucky's Alzheimer's Disease Research Center.


Asunto(s)
Disfunción Cognitiva , Cognición , Estudios de Cohortes , Humanos , Modelos Logísticos , Cadenas de Markov
7.
Alzheimers Dement ; 17(4): 704-715, 2021 04.
Artículo en Inglés | MEDLINE | ID: mdl-33480172

RESUMEN

The concept of vascular contributions to cognitive impairment and dementia (VCID) derives from more than two decades of research indicating that (1) most older individuals with cognitive impairment have post mortem evidence of multiple contributing pathologies and (2) along with the preeminent role of Alzheimer's disease (AD) pathology, cerebrovascular disease accounts for a substantial proportion of this contribution. Contributing cerebrovascular processes include both overt strokes caused by etiologies such as large vessel occlusion, cardioembolism, and embolic infarcts of unknown source, and frequently asymptomatic brain injuries caused by diseases of the small cerebral vessels. Cerebral small vessel diseases such as arteriolosclerosis and cerebral amyloid angiopathy, when present at moderate or greater pathologic severity, are independently associated with worse cognitive performance and greater likelihood of dementia, particularly in combination with AD and other neurodegenerative pathologies. Based on this evidence, the US National Alzheimer's Project Act explicitly authorized accelerated research in vascular and mixed dementia along with frontotemporal and Lewy body dementia and AD itself. Biomarker development has been consistently identified as a key step toward translating scientific advances in VCID into effective prevention and treatment strategies. Validated biomarkers can serve a range of purposes in trials of candidate interventions, including (1) identifying individuals at increased VCID risk, (2) diagnosing the presence of cerebral small vessel disease or specific small vessel pathologies, (3) stratifying study participants according to their prognosis for VCID progression or treatment response, (4) demonstrating an intervention's target engagement or pharmacodynamic mechanism of action, and (5) monitoring disease progression during treatment. Effective biomarkers allow academic and industry investigators to advance promising interventions at early stages of development and discard interventions with low success likelihood. The MarkVCID consortium was formed in 2016 with the goal of developing and validating fluid- and imaging-based biomarkers for the cerebral small vessel diseases associated with VCID. MarkVCID consists of seven project sites and a central coordinating center, working with the National Institute of Neurologic Diseases and Stroke and National Institute on Aging under cooperative agreements. Through an internal selection process, MarkVCID has identified a panel of 11 candidate biomarker "kits" (consisting of the biomarker measure and the clinical and cognitive data used to validate it) and established a range of harmonized procedures and protocols for participant enrollment, clinical and cognitive evaluation, collection and handling of fluid samples, acquisition of neuroimaging studies, and biomarker validation. The overarching goal of these protocols is to generate rigorous validating data that could be used by investigators throughout the research community in selecting and applying biomarkers to multi-site VCID trials. Key features of MarkVCID participant enrollment, clinical/cognitive testing, and fluid biomarker procedures are summarized here, with full details in the following text, tables, and supplemental material, and a description of the MarkVCID imaging biomarker procedures in a companion paper, "MarkVCID Cerebral small vessel consortium: II. Neuroimaging protocols." The procedures described here address a range of challenges in MarkVCID's design, notably: (1) acquiring all data under informed consent and enrollment procedures that allow unlimited sharing and open-ended analyses without compromising participant privacy rights; (2) acquiring the data in a sufficiently wide range of study participants to allow assessment of candidate biomarkers across the various patient groups who might ultimately be targeted in VCID clinical trials; (3) defining a common dataset of clinical and cognitive elements that contains all the key outcome markers and covariates for VCID studies and is realistically obtainable during a practical study visit; (4) instituting best fluid-handling practices for minimizing avoidable sources of variability; and (5) establishing rigorous procedures for testing the reliability of candidate fluid-based biomarkers across replicates, assay runs, sites, and time intervals (collectively defined as the biomarker's instrumental validity). Participant Enrollment Project sites enroll diverse study cohorts using site-specific inclusion and exclusion criteria so as to provide generalizable validation data across a range of cognitive statuses, risk factor profiles, small vessel disease severities, and racial/ethnic characteristics representative of the diverse patient groups that might be enrolled in a future VCID trial. MarkVCID project sites include both prospectively enrolling centers and centers providing extant data and samples from preexisting community- and population-based studies. With approval of local institutional review boards, all sites incorporate MarkVCID consensus language into their study documents and informed consent agreements. The consensus language asks prospectively enrolled participants to consent to unrestricted access to their data and samples for research analysis within and outside MarkVCID. The data are transferred and stored as a de-identified dataset as defined by the Health Insurance Portability and Accountability Act Privacy Rule. Similar human subject protection and informed consent language serve as the basis for MarkVCID Research Agreements that act as contracts and data/biospecimen sharing agreements across the consortium. Clinical and Cognitive Data Clinical and cognitive data are collected across prospectively enrolling project sites using common MarkVCID instruments. The clinical data elements are modified from study protocols already in use such as the Alzheimer's Disease Center program Uniform Data Set Version 3 (UDS3), with additional focus on VCID-related items such as prior stroke and cardiovascular disease, vascular risk factors, focal neurologic findings, and blood testing for vascular risk markers and kidney function including hemoglobin A1c, cholesterol subtypes, triglycerides, and creatinine. Cognitive assessments and rating instruments include the Clinical Dementia Rating Scale, Geriatric Depression Scale, and most of the UDS3 neuropsychological battery. The cognitive testing requires ≈60 to 90 minutes. Study staff at the prospectively recruiting sites undergo formalized training in all measures and review of their first three UDS3 administrations by the coordinating center. Collection and Handling of Fluid Samples Fluid sample types collected for MarkVCID biomarker kits are serum, ethylenediaminetetraacetic acid-plasma, platelet-poor plasma, and cerebrospinal fluid (CSF) with additional collection of packed cells to allow future DNA extraction and analyses. MarkVCID fluid guidelines to minimize variability include fasting morning fluid collections, rapid processing, standardized handling and storage, and avoidance of CSF contact with polystyrene. Instrumental Validation for Fluid-Based Biomarkers Instrumental validation of MarkVCID fluid-based biomarkers is operationally defined as determination of intra-plate and inter-plate repeatability, inter-site reproducibility, and test-retest repeatability. MarkVCID study participants both with and without advanced small vessel disease are selected for these determinations to assess instrumental validity across the full biomarker assay range. Intra- and inter-plate repeatability is determined by repeat assays of single split fluid samples performed at individual sites. Inter-site reproducibility is determined by assays of split samples distributed to multiple sites. Test-retest repeatability is determined by assay of three samples acquired from the same individual, collected at least 5 days apart over a 30-day period and assayed on a single plate. The MarkVCID protocols are designed to allow direct translation of the biomarker validation results to multicenter trials. They also provide a template for outside groups to perform analyses using identical methods and therefore allow direct comparison of results across studies and centers. All MarkVCID protocols are available to the biomedical community and intended to be shared. In addition to the instrumental validation procedures described here, each of the MarkVCID kits will undergo biological validation to determine whether the candidate biomarker measures important aspects of VCID such as cognitive function. Analytic methods and results of these validation studies for the 11 MarkVCID biomarker kits will be published separately. The results of this rigorous validation process will ultimately determine each kit's potential usefulness for multicenter interventional trials aimed at preventing or treating small vessel disease related VCID.


Asunto(s)
Biomarcadores , Enfermedades de los Pequeños Vasos Cerebrales/diagnóstico , Disfunción Cognitiva/diagnóstico , Selección de Paciente , Proyectos de Investigación , Anciano , Demencia/etiología , Progresión de la Enfermedad , Femenino , Humanos , Difusión de la Información , Masculino , Pruebas Neuropsicológicas , Accidente Cerebrovascular/etiología
8.
Acta Neuropathol ; 140(5): 659-674, 2020 11.
Artículo en Inglés | MEDLINE | ID: mdl-32797255

RESUMEN

To better understand clinical and neuropathological features of TDP-43 proteinopathies, data were analyzed from autopsied research volunteers who were followed in the National Alzheimer's Coordinating Center (NACC) data set. All subjects (n = 495) had autopsy-proven TDP-43 proteinopathy as an inclusion criterion. Subjects underwent comprehensive longitudinal clinical evaluations yearly for 6.9 years before death on average. We tested whether an unsupervised clustering algorithm could detect coherent groups of TDP-43 immunopositive cases based on age at death and extensive neuropathologic data. Although many of the brains had mixed pathologies, four discernible clusters were identified. Key differentiating features were age at death and the severity of comorbid Alzheimer's disease neuropathologic changes (ADNC), particularly neuritic amyloid plaque densities. Cluster 1 contained mostly cases with a pathologic diagnosis of frontotemporal lobar degeneration (FTLD-TDP), consistent with enrichment of frontotemporal dementia clinical phenotypes including appetite/eating problems, disinhibition and primary progressive aphasia (PPA). Cluster 2 consisted of elderly limbic-predominant age-related TDP-43 encephalopathy (LATE-NC) subjects without severe neuritic amyloid plaques. Subjects in Cluster 2 had a relatively slow cognitive decline. Subjects in both Clusters 3 and 4 had severe ADNC + LATE-NC; however, Cluster 4 was distinguished by earlier disease onset, swifter disease course, more Lewy body pathology, less neocortical TDP-43 proteinopathy, and a suggestive trend in a subgroup analysis (n = 114) for increased C9orf72 risk SNP rs3849942 T allele (Fisher's exact test p value = 0.095). Overall, clusters enriched with neocortical TDP-43 proteinopathy (Clusters 1 and 2) tended to have lower levels of neuritic amyloid plaques, and those dying older (Clusters 2 and 3) had far less PPA or disinhibition, but more apathy. Indeed, 98% of subjects dying past age 85 years lacked clinical features of the frontotemporal dementia syndrome. Our study revealed discernible subtypes of LATE-NC and underscored the importance of age of death for differentiating FTLD-TDP and LATE-NC.


Asunto(s)
Demencia Frontotemporal/clasificación , Demencia Frontotemporal/patología , Proteinopatías TDP-43/clasificación , Proteinopatías TDP-43/patología , Factores de Edad , Anciano , Anciano de 80 o más Años , Análisis por Conglomerados , Femenino , Humanos , Masculino
9.
FASEB J ; 33(12): 14281-14295, 2019 12.
Artículo en Inglés | MEDLINE | ID: mdl-31661303

RESUMEN

Blood-brain barrier dysfunction in epilepsy contributes to seizures and resistance to antiseizure drugs. Reports show that seizures increase brain glutamate levels, leading to barrier dysfunction. One component of barrier dysfunction is overexpression of the drug efflux transporters P-glycoprotein (P-gp) and breast cancer resistance protein (BCRP). Based on our previous studies, we hypothesized that glutamate released during seizures activates cytosolic phospholipase A2 (cPLA2), resulting in P-gp and BCRP overexpression. We exposed isolated rat brain capillaries to glutamate ex vivo and used an in vivo-ex vivo approach of isolating brain capillaries from rats after status epilepticus (SE) and in chronic epileptic (CE) rats. Glutamate increased cPLA2, P-gp, and BCRP protein and activity levels in isolated brain capillaries. We confirmed the role of cPLA2 in the signaling pathway in brain capillaries from male and female mice lacking cPLA2. We also demonstrated, in vivo, that cPLA2 inhibition prevents overexpression of P-gp and BCRP at the blood-brain barrier in rats after status epilepticus and in CE rats. Our data support the hypothesis that glutamate signals cPLA2 activation, resulting in overexpression of blood-brain barrier P-gp and BCRP.-Hartz, A. M. S., Rempe, R. G., Soldner, E. L. B., Pekcec, A., Schlichtiger, J., Kryscio, R., Bauer, B. Cytosolic phospholipase A2 is a key regulator of blood-brain barrier function in epilepsy.


Asunto(s)
Barrera Hematoencefálica/enzimología , Epilepsia/enzimología , Fosfolipasas A2 Grupo IV/metabolismo , Animales , Barrera Hematoencefálica/metabolismo , Encéfalo/irrigación sanguínea , Encéfalo/enzimología , Capilares/enzimología , Epilepsia/genética , Regulación Enzimológica de la Expresión Génica/efectos de los fármacos , Regulación Enzimológica de la Expresión Génica/fisiología , Genotipo , Ácido Glutámico/farmacología , Fosfolipasas A2 Grupo IV/genética , Masculino , Ratones , Ratas , Ratas Sprague-Dawley
10.
FASEB J ; 33(12): 13966-13981, 2019 12.
Artículo en Inglés | MEDLINE | ID: mdl-31638830

RESUMEN

The cause of antiseizure drug (ASD) resistance in epilepsy is poorly understood. Here, we focus on the transporter P-glycoprotein (P-gp) that is partly responsible for limited ASD brain uptake, which is thought to contribute to ASD resistance. We previously demonstrated that cyclooxygenase-2 (COX-2) and the prostaglandin E receptor, prostanoid E receptor subtype 1, are involved in seizure-mediated P-gp up-regulation. Thus, we hypothesized that inhibiting microsomal prostaglandin E2 (PGE2) synthase-1 (mPGES-1), the enzyme generating PGE2, prevents blood-brain barrier P-gp up-regulation after status epilepticus (SE). To test our hypothesis, we exposed isolated brain capillaries to glutamate ex vivo and used a combined in vivo-ex vivo approach by isolating brain capillaries from humanized mPGES-1 mice to study P-gp levels. We demonstrate that glutamate signaling through the NMDA receptor, cytosolic phospholipase A2, COX-2, and mPGES-1 increases P-gp protein expression and transport activity levels. We show that mPGES-1 is expressed in human, rat, and mouse brain capillaries. We show that BI1029539, an mPGES-1 inhibitor, prevented up-regulation of P-gp expression and transport activity in capillaries exposed to glutamate and in capillaries from humanized mPGES-1 mice after SE. Our data provide key signaling steps underlying seizure-induced P-gp up-regulation and suggest that mPGES-1 inhibitors could potentially prevent P-gp up-regulation in epilepsy.-Soldner, E. L. B., Hartz, A. M. S., Akanuma, S.-I., Pekcec, A., Doods, H., Kryscio, R. J., Hosoya, K.-I., Bauer, B. Inhibition of human microsomal PGE2 synthase-1 reduces seizure-induced increases of P-glycoprotein expression and activity at the blood-brain barrier.


Asunto(s)
Miembro 1 de la Subfamilia B de Casetes de Unión a ATP/metabolismo , Barrera Hematoencefálica/metabolismo , Dinoprostona/metabolismo , Microsomas/metabolismo , Prostaglandina-E Sintasas/metabolismo , Convulsiones/metabolismo , Animales , Transporte Biológico/fisiología , Encéfalo/metabolismo , Capilares/metabolismo , Ciclooxigenasa 2/metabolismo , Epilepsia/metabolismo , Femenino , Ácido Glutámico/metabolismo , Humanos , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Transgénicos , Ratas , Ratas Sprague-Dawley , Transducción de Señal/fisiología , Regulación hacia Arriba/fisiología
11.
J Clin Periodontol ; 47(4): 442-450, 2020 04.
Artículo en Inglés | MEDLINE | ID: mdl-31860742

RESUMEN

AIM: To investigate the role of Epstein-Barr virus (EBV), cytomegalovirus (CMV), and anaerobic bacteria in the progression of periodontitis. METHODS: Eighty-one adults with generalized moderate to severe periodontitis were randomly assigned to: oral hygiene or scaling and root planning ± placebo or polyunsaturated fatty acids fish oil. Subgingival plaque samples collected from three healthy and three disease sites at weeks 0, 16, and 28 and from sites demonstrating disease progression were analysed for EBV, CMV, P. gingivalis (Pg), T. forsythia (Tf), and T. denticola (Td) DNA using quantitative polymerase chain reaction. RESULTS: Cytomegalovirus was detected in 0.3% (4/1454) sites. EBV was present in 12.2% of healthy sites (89/728) and 27.6% disease sites (201/726; p < .0001), but was in low copy number. Disease progression occurred in 28.4% of participants (23/81) and developed predominantly at sites identified as diseased (75/78; 96.2%). CMV and EBV were not associated with disease progression (p = .13) regardless of treatment. In contrast, disease sites were associated with higher levels of Pg, Td, Tf, and total bacteria, and sites that exhibited disease progression were associated with an abundance of Td and Tf (p < .04). CONCLUSION: Disease progression was associated with Gram-negative anaerobic bacteria; not EBV or CMV.


Asunto(s)
Herpesviridae , Periodontitis , Adulto , Citomegalovirus , Progresión de la Enfermedad , Herpesvirus Humano 4 , Humanos
12.
J Neurosci ; 38(18): 4301-4315, 2018 05 02.
Artículo en Inglés | MEDLINE | ID: mdl-29632167

RESUMEN

The blood-brain barrier is dysfunctional in epilepsy, thereby contributing to seizure genesis and resistance to antiseizure drugs. Previously, several groups reported that seizures increase brain glutamate levels, which leads to barrier dysfunction. One critical component of barrier dysfunction is brain capillary leakage. Based on our preliminary data, we hypothesized that glutamate released during seizures mediates an increase in matrix-metalloproteinase (MMP) expression and activity levels, thereby contributing to barrier leakage. To test this hypothesis, we exposed isolated brain capillaries from male Sprague Dawley rats to glutamate ex vivo and used an in vivo/ex vivo approach of isolated brain capillaries from female Wistar rats that experienced status epilepticus as an acute seizure model. We found that exposing isolated rat brain capillaries to glutamate increased MMP-2 and MMP-9 protein and activity levels, and decreased tight junction protein levels, which resulted in barrier leakage. We confirmed these findings in vivo in rats after status epilepticus and in brain capillaries from male mice lacking cytosolic phospholipase A2 Together, our data support the hypothesis that glutamate released during seizures signals an increase in MMP-2 and MMP-9 protein expression and activity levels, resulting in blood-brain barrier leakage.SIGNIFICANCE STATEMENT The mechanism leading to seizure-mediated blood-brain barrier dysfunction in epilepsy is poorly understood. In the present study, we focused on defining this mechanism in the brain capillary endothelium. We demonstrate that seizures trigger a pathway that involves glutamate signaling through cytosolic phospholipase A2, which increases MMP levels and decreases tight junction protein expression levels, resulting in barrier leakage. These findings may provide potential therapeutic avenues within the blood-brain barrier to limit barrier dysfunction in epilepsy and decrease seizure burden.


Asunto(s)
Barrera Hematoencefálica/patología , Epilepsia/patología , Metaloproteinasas de la Matriz/metabolismo , Animales , Capilares/efectos de los fármacos , Femenino , Masculino , Metaloproteinasa 2 de la Matriz/metabolismo , Metaloproteinasa 9 de la Matriz/metabolismo , Ratones , Ratas , Ratas Sprague-Dawley , Ratas Wistar , Convulsiones/patología , Estado Epiléptico/metabolismo , Estado Epiléptico/patología , Proteínas de Uniones Estrechas/metabolismo
14.
Stat Med ; 38(12): 2103-2114, 2019 05 30.
Artículo en Inglés | MEDLINE | ID: mdl-30680767

RESUMEN

The Nun Study, a longitudinal study to examine risk factors for the progression of dementia, consists of subjects who were already diagnosed with dementia (ie, prevalent cohort) and those who do not have dementia (ie, incident cohort) at study enrollment. When assessing the risk factors' effects on the survival time from dementia diagnosis until death, utilizing data from both cohorts supports more efficient statistical inference because the two cohorts provide valuable complementary information. A major challenge in analyzing the combined cohort data is that the prevalent cases are not representative of the target population. Moreover, the dates of dementia diagnosis are not ascertained for the prevalent cohort in the Nun Study. Hence, the survival time for the prevalent cohort is only partially observed from study enrollment until death or censoring, with the time from dementia diagnosis to study enrollment missing. In this paper, we propose an efficient estimation method that uses both incident and prevalent cohorts under the proportional mean residual life model. By assuming proportionality of the mean residual life time with covariates in the incident cohort, we can utilize the natural relationship between the mean residual life function and the hazard function of the survival time measured from enrollment until death for the prevalent cohort. We evaluate the efficiency gain from using the combined cohort data through simulations and demonstrate that the proposed method is valid and efficient.


Asunto(s)
Estudios de Cohortes , Incidencia , Prevalencia , Modelos de Riesgos Proporcionales , Anciano , Anciano de 80 o más Años , Simulación por Computador , Demencia , Progresión de la Enfermedad , Femenino , Humanos
15.
Cerebrovasc Dis ; 48(3-6): 251-256, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31851968

RESUMEN

INTRODUCTION: Mechanical thrombectomy has become standard of care for emergent large vessel occlusive stroke. Estimates of incidence for thrombectomy eligibility vary significantly. National Institutes of Health Stroke Scale (NIHSS) of 10 or greater is highly predictive of large vessel occlusion. Using our Kentucky Appalachian Stroke Registry (KApSR), we evaluated temporal trends in stroke admissions with NIHSS ≥10 to determine patient characteristics among that group along with effects and needs in thrombectomy utilization. METHODS: Using the KApSR database that captures patients throughout the Appalachian region in our stroke network, we evaluated patients admitted with ischemic stroke with NIHSS ≥10. We recorded demographics, comorbidities, treatment (thrombectomy, decompressive craniectomy), and county of origin. Change in NIHSS from admission to discharge was used as an indicator of inpatient outcome. RESULTS: Between 2010 and 2016, 1,510 patients were admitted with NIHSS ≥10. 87.2% had high blood pressure, 69.6% had dyslipidemia, and 41.7% used tobacco. There were significant sex differences in the types of patients presenting with NIHSS ≥10 with females being older on average and having more atrial fibrillation and obesity. There was an increase in thrombectomy utilization from 2010 to 2016, but only 7.5% of the potentially eligible patients underwent the procedure. In comparison to the period 2010-2014, the 2015-2016 period had higher rates of obesity and tobacco abuse. CONCLUSION: Among patients with significant burden of ischemic stroke, the most common coexisting medical condition was high blood pressure. Patients who underwent thrombectomy had significantly better inpatient clinical improvement. These data support the need to maximize utilization of thrombectomy along with need to devote increased resources on modifiable stroke risk factors.


Asunto(s)
Isquemia Encefálica/terapia , Toma de Decisiones Clínicas , Técnicas de Apoyo para la Decisión , Evaluación de la Discapacidad , Selección de Paciente , Accidente Cerebrovascular/terapia , Trombectomía , Factores de Edad , Anciano , Anciano de 80 o más Años , Región de los Apalaches/epidemiología , Isquemia Encefálica/diagnóstico , Isquemia Encefálica/epidemiología , Isquemia Encefálica/fisiopatología , Comorbilidad , Estudios Transversales , Femenino , Estado de Salud , Humanos , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Sistema de Registros , Estudios Retrospectivos , Medición de Riesgo , Factores de Riesgo , Factores Sexuales , Accidente Cerebrovascular/diagnóstico , Accidente Cerebrovascular/epidemiología , Accidente Cerebrovascular/fisiopatología , Trombectomía/efectos adversos , Resultado del Tratamiento
16.
Clin Infect Dis ; 66(6): 886-892, 2018 03 05.
Artículo en Inglés | MEDLINE | ID: mdl-29069328

RESUMEN

Background: Tuberculosis has been associated with an increased risk of cardiovascular disease (CVD), including acute myocardial infarction (AMI). We investigated whether latent tuberculosis infection (LTBI) is associated with AMI. Methods: We conducted a case-control study in 2 large national public hospital networks in Lima, Peru, between July 2015 and March 2017. Case patients were patients with a first time diagnosis of type 1 (spontaneous) AMI. Controls were patients without a history of AMI. We excluded patients with known human immunodeficiency virus infection, tuberculosis disease, or prior LTBI treatment. We used the QuantiFERON-TB Gold In-Tube assay to identify LTBI. We used logistic regression modeling to estimate the odds ratio (OR) of LTBI in AMI case patients versus non-AMI controls. Results: We enrolled 105 AMI case patients and 110 non-AMI controls during the study period. Overall, the median age was 62 years (interquartile range, 56-70 years); 69% of patients were male; 64% had hypertension, 40% dyslipidemia, and 39% diabetes mellitus; 30% used tobacco; and 24% were obese. AMI case patients were more likely than controls to be male (80% vs 59%; P < .01) and tobacco users (41% vs 20%; P < .01). LTBI was more frequent in AMI case patients than in controls (64% vs 49% [P = .03]; OR, 1.86; 95% confidence interval [CI], 1.08-3.22). After adjustment for age, sex, hypertension, dyslipidemia, diabetes mellitus, tobacco use, obesity, and family history of coronary artery disease, LTBI remained independently associated with AMI (adjusted OR, 1.90; 95% CI, 1.05-3.45). Conclusions: LTBI was independently associated with AMI. Our results suggest a potentially important role of LTBI in CVD.


Asunto(s)
Tuberculosis Latente/complicaciones , Infarto del Miocardio/complicaciones , Anciano , Estudios de Casos y Controles , Femenino , Humanos , Tuberculosis Latente/diagnóstico , Modelos Logísticos , Masculino , Persona de Mediana Edad , Perú , Factores de Riesgo
17.
Ann Neurol ; 81(4): 549-559, 2017 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-28224671

RESUMEN

OBJECTIVE: To determine clinical and neuropathological outcomes following a clinical diagnosis of mild cognitive impairment (MCI). METHODS: Data were drawn from a large autopsy series (N = 1,337) of individuals followed longitudinally from normal or MCI status to death, derived from 4 Alzheimer Disease (AD) Centers in the United States. RESULTS: Mean follow-up was 7.9 years. Of the 874 individuals ever diagnosed with MCI, final clinical diagnoses were varied: 39.2% died with an MCI diagnosis, 46.8% with a dementia diagnosis, and 13.9% with a diagnosis of intact cognition. The latter group had pathological features resembling those with a final clinical diagnosis of MCI. In terms of non-AD pathologies, both primary age-related tauopathy (p < 0.05) and brain arteriolosclerosis pathology (p < 0.001) were more severe in MCI than cognitively intact controls. Among the group that remained MCI until death, mixed AD neuropathologic changes (ADNC; ≥1 comorbid pathology) were more frequent than "pure" ADNC pathology (55% vs 22%); suspected non-Alzheimer pathology comprised the remaining 22% of cases. A majority (74%) of subjects who died with MCI were without "high"-level ADNC, Lewy body disease, or hippocampal sclerosis pathologies; this group was enriched in cerebrovascular pathologies. Subjects who died with dementia and were without severe neurodegenerative pathologies tended to have cerebrovascular pathology and carry the MCI diagnosis for a longer interval. INTERPRETATION: MCI diagnosis usually was associated with comorbid neuropathologies; less than one-quarter of MCI cases showed "pure" AD at autopsy. Ann Neurol 2017;81:549-559.


Asunto(s)
Arterioloesclerosis/patología , Disfunción Cognitiva/patología , Demencia/patología , Arteriosclerosis Intracraneal/patología , Tauopatías/patología , Anciano , Anciano de 80 o más Años , Enfermedad de Alzheimer/patología , Arterioloesclerosis/clasificación , Autopsia , Disfunción Cognitiva/clasificación , Demencia/clasificación , Femenino , Estudios de Seguimiento , Humanos , Arteriosclerosis Intracraneal/clasificación , Masculino , Tauopatías/clasificación
18.
J Pediatr Orthop ; 38(8): 430-435, 2018 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-27636913

RESUMEN

BACKGROUND: Idiopathic clubfoot treatment is treated by manipulation and casting utilizing the Ponseti technique which can make the infant fussy and irritable. The goal of this study was to determine which intervention could decrease this pain response in infants undergoing Ponseti casting for idiopathic clubfeet. Our hypothesis was that the administration of oral sucrose solution or milk would be the most effective in accomplishing that goal. METHODS: We conducted a double-blinded randomized controlled trial at a tertiary pediatric orthopaedic center on 33 children (average age=17.94 d; SD=20.51 d) undergoing clubfoot manipulation and casting and their guardians. Each cast was considered a new event and was randomized to an oral 20% sucrose solution (S), water (W), or milk (M) in a bottle (breast or nonbreast). We assessed the Neonatal Infant Pain Scale (NIPS), heart rate, and oxygen saturation before, during, and after the casting. RESULTS: A total of 131 casts were randomized and 118 analyzed (37 M, 42 S, 39 W). Each child underwent an average of 3.97 casts (SD=1.74). There were no significant differences seen between the groups before casting in their mean NIPS score (M=2.2; SD=2.38, S=1.84, SD=2.18, W=1.61, SD=2.12). However during casting, mean NIPS score for both milk, 0.91 (SD=1.26, P=0.0005) and sucrose, 0.64 (SD=1.27, P<0.0001) were significantly less than water, 2.27 (SD=2.03) but not different from each other (P=0.33). Postcasting, the sucrose NIPS score, 0.69 (SD=1.53) continued to be significantly less than milk, 2.11 (SD=2.37, P=0.0065. There was no correlation between heart rate or oxygen saturation and NIPS. CONCLUSIONS: Sucrose solution and milk during Ponseti casting and manipulation were effective in decreasing the pain response in children undergoing manipulation and casting for clubfeet. The sucrose solution administration continued the pain relief into the postcasting period. In addition to the benefits of improving the patient experience during casting, a less irritable child may result in better casting. LEVEL OF EVIDENCE: Level 1 evidence.


Asunto(s)
Moldes Quirúrgicos , Pie Equinovaro/terapia , Manejo del Dolor/métodos , Dolor Asociado a Procedimientos Médicos/prevención & control , Sacarosa/administración & dosificación , Edulcorantes/administración & dosificación , Administración Oral , Método Doble Ciego , Femenino , Frecuencia Cardíaca/fisiología , Humanos , Lactante , Recién Nacido , Masculino , Dimensión del Dolor/métodos , Padres/psicología , Resultado del Tratamiento
19.
Stat Med ; 36(18): 2935-2946, 2017 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-28513091

RESUMEN

In environmental exposure studies, it is common to observe a portion of exposure measurements to fall below experimentally determined detection limits (DLs). The reverse Kaplan-Meier estimator, which mimics the well-known Kaplan-Meier estimator for right-censored survival data with the scale reversed, has been recommended for estimating the exposure distribution for the data subject to DLs because it does not require any distributional assumption. However, the reverse Kaplan-Meier estimator requires the independence assumption between the exposure level and DL and can lead to biased results when this assumption is violated. We propose a kernel-smoothed nonparametric estimator for the exposure distribution without imposing any independence assumption between the exposure level and DL. We show that the proposed estimator is consistent and asymptotically normal. Simulation studies demonstrate that the proposed estimator performs well in practical situations. A colon cancer study is provided for illustration. Copyright © 2017 John Wiley & Sons, Ltd.


Asunto(s)
Exposición a Riesgos Ambientales/análisis , Modelos Estadísticos , Región de los Apalaches/epidemiología , Bioestadística , Neoplasias del Colon/química , Neoplasias del Colon/etiología , Simulación por Computador , Exposición a Riesgos Ambientales/efectos adversos , Humanos , Estimación de Kaplan-Meier , Límite de Detección , Estadísticas no Paramétricas , Análisis de Supervivencia , Oligoelementos/efectos adversos , Oligoelementos/análisis
20.
BMC Ophthalmol ; 17(1): 78, 2017 May 22.
Artículo en Inglés | MEDLINE | ID: mdl-28532424

RESUMEN

BACKGROUND: The purpose of this study is to evaluate the number of eyedrops available per bottle of a variety of commonly prescribed glaucoma medications. METHODS: Six bottles of each glaucoma medication were tested: three each in the vertical and horizontal orientations. Bottles were housed in a customized force gauge apparatus designed to mimic ballpoint fingertip contact with a bottle. At a standard rate, all drops were expressed from each bottle and counted with an automated drop counter. Simultaneously, bottle volume was measured and drop size and number were also estimated. The main outcome measures were: total number of drops, volume per bottle and drops per milliliter (mL) of glaucoma medication. RESULTS: A total of 192 bottles from 32 bottle designs and manufacturers were tested. Twenty-two of the 32 bottle designs had a significantly different mean number of drops in the vertical and horizontal positions, with 10 designs have more drops dispensed in the horizontal orientation and 12 in the vertical orientation. Six of the 32 bottle designs had a significantly different mean total bottle volume in the vertical and horizontal positions, with all designs having greater volume in the vertical position. An adjusted ratio of mean number of drops/mean bottle volume demonstrated a range from 20.9 drops/mL to 40.8 drops/mL. CONCLUSIONS: There is significant variability in drops and volume available per bottle of glaucoma medication depending on both the bottle position and manufacturer. These data point to the need for circumspection in prescribing glaucoma medications and caution in evaluating therapeutic outcomes.


Asunto(s)
Antihipertensivos/administración & dosificación , Embalaje de Medicamentos , Presión Intraocular/efectos de los fármacos , Glaucoma/tratamiento farmacológico , Glaucoma/fisiopatología , Humanos , Soluciones Oftálmicas
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