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1.
Cell ; 186(2): 305-326.e27, 2023 01 19.
Artigo em Inglês | MEDLINE | ID: mdl-36638792

RESUMO

All living things experience an increase in entropy, manifested as a loss of genetic and epigenetic information. In yeast, epigenetic information is lost over time due to the relocalization of chromatin-modifying proteins to DNA breaks, causing cells to lose their identity, a hallmark of yeast aging. Using a system called "ICE" (inducible changes to the epigenome), we find that the act of faithful DNA repair advances aging at physiological, cognitive, and molecular levels, including erosion of the epigenetic landscape, cellular exdifferentiation, senescence, and advancement of the DNA methylation clock, which can be reversed by OSK-mediated rejuvenation. These data are consistent with the information theory of aging, which states that a loss of epigenetic information is a reversible cause of aging.


Assuntos
Envelhecimento , Epigênese Genética , Animais , Envelhecimento/genética , Metilação de DNA , Epigenoma , Mamíferos/genética , Nucleoproteínas , Saccharomyces cerevisiae/genética
3.
Alzheimers Dement ; 19(5): 1865-1875, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36331050

RESUMO

INTRODUCTION: Potentially inappropriate medications (PIMs) cause adverse events and death. We evaluate the Care Ecosystem (CE) collaborative dementia care program on medication use among community-dwelling persons living with dementia (PLWD). METHODS: Secondary analysis of a randomized clinical trial (RCT) comparing CE to usual care (UC) on changes in PIMs, over 12 months between March 2015 and May 2020. Secondary outcomes included change in number of medications, clinically relevant PIMs, and anti-dementia medications. RESULTS: Of 804 PLWD, N = 490 had complete medication data. The CE resulted in significantly fewer PIMs compared to UC (-0.35; 95% CI, -0.49 to -0.20; P < 0.0001). Number needed to prevent an increase in 1 PIM was 3. Total medications, PIMs for dementia or cognitive impairment, CNS-active PIMs, anticholinergics, benzodiazepines, and opioids were also fewer. Anti-dementia medication regimens were modified more frequently. CONCLUSION: The CE medication review intervention embedded in collaborative dementia care optimized medication use among PLWD. HIGHLIGHTS: Compared to usual care (UC), the Care Ecosystem (CE) medication review intervention prevented increases in potentially inappropriate medications (PIMs). Use of anticholinergics, benzodiazepines, and opioids were significantly reduced, with a trend for antipsychotics. Anti-dementia medications were adjusted more frequently. The CE medication review intervention embedded in collaborative dementia care optimized medication use.


Assuntos
Prescrição Inadequada , Lista de Medicamentos Potencialmente Inapropriados , Humanos , Vida Independente , Antagonistas Colinérgicos , Benzodiazepinas , Polimedicação
4.
J Biol Chem ; 295(32): 10988-11001, 2020 08 07.
Artigo em Inglês | MEDLINE | ID: mdl-32554807

RESUMO

The development of the dendritic arbor in pyramidal neurons is critical for neural circuit function. Here, we uncovered a pathway in which δ-catenin, a component of the cadherin-catenin cell adhesion complex, promotes coordination of growth among individual dendrites and engages the autophagy mechanism to sculpt the developing dendritic arbor. Using a rat primary neuron model, time-lapse imaging, immunohistochemistry, and confocal microscopy, we found that apical and basolateral dendrites are coordinately sculpted during development. Loss or knockdown of δ-catenin uncoupled this coordination, leading to retraction of the apical dendrite without altering basolateral dendrite dynamics. Autophagy is a key cellular pathway that allows degradation of cellular components. We observed that the impairment of the dendritic arbor resulting from δ-catenin knockdown could be reversed by knockdown of autophagy-related 7 (ATG7), a component of the autophagy machinery. We propose that δ-catenin regulates the dendritic arbor by coordinating the dynamics of individual dendrites and that the autophagy mechanism may be leveraged by δ-catenin and other effectors to sculpt the developing dendritic arbor. Our findings have implications for the management of neurological disorders, such as autism and intellectual disability, that are characterized by dendritic aberrations.


Assuntos
Autofagia , Cateninas/metabolismo , Células Dendríticas/metabolismo , Animais , Proteína 7 Relacionada à Autofagia/genética , Cateninas/genética , Células Cultivadas , Técnicas de Silenciamento de Genes , Hipocampo/citologia , Hipocampo/metabolismo , Camundongos , Células Piramidais/metabolismo , Ratos , delta Catenina
5.
Alzheimers Dement ; 15(7): 899-906, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31175026

RESUMO

INTRODUCTION: Dementia is among the costliest of medical conditions, but it is not known how these costs vary by dementia subtype. METHODS: The effect of dementia diagnosis subtype on direct health care costs and utilization was estimated using 2015 California Medicare fee-for-service data. Potential drivers of increased costs in Lewy body dementia (LBD), in comparison to Alzheimer's disease, were tested. RESULTS: 3,001,987 Medicare beneficiaries were identified, of which 8.2% had a dementia diagnosis. Unspecified dementia was the most common diagnostic category (59.6%), followed by Alzheimer's disease (23.2%). LBD was the costliest subtype to Medicare, on average, followed by vascular dementia. The higher costs in LBD were explained in part by falls, urinary incontinence or infection, depression, anxiety, dehydration, and delirium. DISCUSSION: Dementia subtype is an important predictor of health care costs. Earlier identification and targeted treatment might mitigate the costs associated with co-occurring conditions in LBD.


Assuntos
Demência , Planos de Pagamento por Serviço Prestado/economia , Custos de Cuidados de Saúde , Serviços de Saúde para Idosos/estatística & dados numéricos , Medicare/economia , Idoso , Idoso de 80 Anos ou mais , California , Demência/classificação , Demência/economia , Demência Vascular , Feminino , Serviços de Saúde para Idosos/economia , Humanos , Doença por Corpos de Lewy/economia , Masculino , Estados Unidos
6.
BMC Neurosci ; 19(1): 27, 2018 05 02.
Artigo em Inglês | MEDLINE | ID: mdl-29716523

RESUMO

BACKGROUND: Galectins are a large family of proteins evolved to recognize specific carbohydrate moieties. Given the importance of pattern recognition processes for multiple biological tasks, including CNS development and immune recognition, we examined the home cage behavioral phenotype of mice lacking galectin-3 (Lgals3) function. Using a sophisticated monitoring apparatus capable of examining feeding, drinking, and movement at millisecond temporal and 0.5 cm spatial resolutions, we observed daily behavioral patterns from 10 wildtype male C57BL/6J and 10 Lgals3 constitutive knockout (Lgals3-/-; both cohorts aged 2-3 months) mice over 17 consecutive days. We performed a second behavioral assessment of this cohort at age 6-7 months. RESULTS: At both ages, Lgals3-/- mice demonstrated less movement compared to wildtype controls. Both forward locomotion and movement-in-place behaviors were decreased in Lgals3-/- mice, due to decreased bout numbers, initiation rates, and durations. We additionally noted perturbation of behavioral circadian rhythms in Lgals3-/- mice, with mice at both ages demonstrating greater variability in day-to-day performance of feeding, drinking, and movement (as assessed by Lomb-Scargle analysis) compared to wildtype. CONCLUSION: Carbohydrate recognition tasks performed by Lgals3 may be required for appropriate development of CNS structures involved in the generation and control of locomotor behavior.


Assuntos
Comportamento Animal/fisiologia , Ritmo Circadiano/fisiologia , Galectina 3/deficiência , Locomoção/genética , Animais , Camundongos Endogâmicos C57BL , Camundongos Knockout , Reconhecimento Psicológico/fisiologia
8.
HIV Clin Trials ; 14(4): 165-74, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23924589

RESUMO

OBJECTIVES: Emerging data suggest that HIV disease and its treatment affect the aging process. Accurate and reliable measures of functional status are needed to investigate this further. DESIGN: A pilot study in groups of younger and older HIV-infected adults using objective measures of function. METHODS: Evaluations included neuropsychological testing, grip strength, balance assessed by the Wii Balance Board, and actigraphy. Surveys were used for depression, fatigue, loneliness, self-reported activity level, and sexual function. Two-samplet test or Wilcoxon rank sum tests were used for continuous variables and exact chi-square tests were used for comparison between groups. RESULTS: Twenty-one participants were 20 to 40 years old (younger; mean age, 31.5), and 20 were more than 50 years old (older; mean age, 56.5). There was no difference between groups for depression, fatigue, or loneliness. Overall, there was a trend to lower scores in the older age group for neuropsychologicalz score (P = .11) and for verbal learning (P = .09). Functioning in the memory domain was significantly lower in older subjects (P = .007). There was no difference in executive function, speed of processing, memory, motor skills, or total activity. Gender differences in sexual function were observed. Four older and 3 younger participants met the definition of frailty. Total activity by actigraphy did not correlate well with self-reported activity. CONCLUSIONS: Objective tests were well accepted and feasible to perform, although not all are suitable for widespread clinical or research use. Objective measurements of activity did not correlate well with patient self-report, which has implications for future studies in this area.


Assuntos
Infecções por HIV/psicologia , Adulto , Fatores Etários , Idoso , Estudos Transversais , Função Executiva , Feminino , Humanos , Masculino , Memória , Pessoa de Meia-Idade , Destreza Motora , Testes Neuropsicológicos , Projetos Piloto , Caracteres Sexuais
9.
Environ Plann B Plann Des ; 40(2): 350-361, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28819332

RESUMO

Life-space is a promising method for estimating older adults' functional status. However, traditional life-space measures are costly and time consuming because they often rely on active subject participation. This study assesses the feasibility of using the global positioning system (GPS) function of smart phones to generate life-space indicators. We first evaluated the location accuracy of smart phone collected GPS points versus those acquired by a commercial GPS unit. We then assessed the specificity of the smart phone processed life-space information against the traditional diary method. Our results suggested comparable location accuracy between the smart phone and the standard GPS unit in most outdoor situations. In addition, the smart phone method revealed more comprehensive life-space information than the diary method, which leads to higher and more consistent life-space scores. We conclude that the smart phone method is more reliable than traditional methods for measuring life-space. Further improvements will be required to develop a robust application of this method that is suitable for health-related practices.

10.
Dev Neurobiol ; 83(5-6): 184-204, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37433012

RESUMO

Fetal alcohol spectrum disorders are one of the leading causes of developmental abnormalities worldwide. Maternal consumption of alcohol during pregnancy leads to a diverse range of cognitive and neurobehavioral deficits. Although moderate-to-heavy levels of prenatal alcohol exposure (PAE) have been associated with adverse offspring outcomes, there is limited data on the consequences of chronic low-level PAE. Here, we use a model of maternal voluntary alcohol consumption throughout gestation in a mouse model to investigate the effects of PAE on behavioral phenotypes during late adolescence and early adulthood in male and female offspring. Body composition was measured by dual-energy X-ray absorptiometry. Baseline behaviors, including feeding, drinking, and movement, were examined by performing home cage monitoring studies. The impact of PAE on motor function, motor skill learning, hyperactivity, acoustic reactivity, and sensorimotor gating was investigated by performing a battery of behavioral tests. PAE was found to be associated with altered body composition. No differences in overall movement, food, or water consumption were observed between control and PAE mice. Although PAE offspring of both sexes exhibited deficits in motor skill learning, no differences were observed in basic motor skills such as grip strength and motor coordination. PAE females exhibited a hyperactive phenotype in a novel environment. PAE mice exhibited increased reactivity to acoustic stimuli, and PAE females showed disrupted short-term habituation. Sensorimotor gating was not altered in PAE mice. Collectively, our data show that chronic low-level exposure to alcohol in utero results in behavioral impairments.


Assuntos
Transtornos do Espectro Alcoólico Fetal , Efeitos Tardios da Exposição Pré-Natal , Humanos , Camundongos , Gravidez , Animais , Feminino , Masculino , Aprendizagem , Etanol/toxicidade , Fenótipo
11.
J Am Geriatr Soc ; 71(7): 2172-2183, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-36917135

RESUMO

BACKGROUND: Dementia can impede the relationship and connection between the person with dementia (PWD) and their caregiver. Yet, caregiving in dementia also offers opportunities for connection, which has implications for caregiver and PWD well-being. In this qualitative study, we describe and characterize ways caregivers felt connected to the person with dementia they care for. METHODS: We conducted a telephone-based survey with caregivers of people with dementia. For this paper, we analyzed responses to an open-ended question focused on when caregivers feel most connected to the person they are caring for. Responses were analyzed and coded and themes were identified through an iterative process involving a multidisciplinary team of researchers and clinicians. RESULTS: 437 caregivers participated in this study. We identified two domains of connection: activity-based and emotion-based connections. Within activity-based connections, the following themes emerged: everyday activities; reminiscing; activities of caregiving; novel experiences; and time with family and friends. Within emotional connections, the following themes emerged: expressions of love, appreciation, and gratitude; physical affection; sharing an emotion or emotional experience; and times when the PWD seems like "themself" again. CONCLUSIONS: Findings provide insights into ways caregivers experience a sense of connection with the person they care for. There is a call to shift away from focusing on reducing stress and toward optimizing positive experiences as a way to better support caregivers' health and well-being. Interventions that leverage these insights to foster caregiver - PWD connection could lead to better health and well-being for both members of the dyad. The amplification of a positive experience may be particularly important for caregivers who are struggling with limited support or respite. Clinicians may be interested in using a question about connection as a way to more fully understand a caregiver's current experience.


Assuntos
Demência , Amor , Feminino , Humanos , Cuidadores/psicologia , Demência/psicologia , Emoções , Satisfação Pessoal
12.
JAMA Intern Med ; 183(11): 1222-1228, 2023 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-37721734

RESUMO

Importance: Collaborative dementia care programs are effective in addressing the needs of patients with dementia and their caregivers. However, attempts to consider effects on health care spending have been limited, leaving a critical gap in the conversation around value-based dementia care. Objective: To determine the effect of participation in collaborative dementia care on total Medicare reimbursement costs compared with usual care. Design, Setting, and Participants: This was a prespecified secondary analysis of the Care Ecosystem trial, a 12-month, single-blind, parallel-group randomized clinical trial conducted from March 2015 to March 2018 at 2 academic medical centers in California and Nebraska. Participants were patients with dementia who were living in the community, aged 45 years or older, and had a primary caregiver and Medicare fee-for-service coverage for the duration of the trial. Intervention: Telehealth dementia care program that entailed assignment to an unlicensed dementia care guide who provided caregiver support, standardized education, and connection to licensed dementia care specialists. Main Outcomes and Measures: Primary outcome was the sum of all Medicare claim payments during study enrollment, excluding Part D (drugs). Results: Of the 780 patients in the Care Ecosystem trial, 460 (59.0%) were eligible for and included in this analysis. Patients had a median (IQR) age of 78 (72-84) years, and 256 (55.7%) identified as female. Participation in collaborative dementia care reduced the total cost of care by $3290 from 1 to 6 months postenrollment (95% CI, -$6149 to -$431; P = .02) and by $3027 from 7 to 12 months postenrollment (95% CI, -$5899 to -$154; P = .04), corresponding overall to a mean monthly cost reduction of $526 across 12 months. An evaluation of baseline predictors of greater cost reduction identified trends for recent emergency department visit (-$5944; 95% CI, -$10 336 to -$1553; interaction P = .07) and caregiver depression (-$6556; 95% CI, -$11 059 to -$2052; interaction P = .05). Conclusions and Relevance: In this secondary analysis of a randomized clinical trial among Medicare beneficiaries with dementia, the Care Ecosystem model was associated with lower total cost of care compared with usual care. Collaborative dementia care programs are a cost-effective, high-value model for dementia care. Trial Registration: ClinicalTrials.gov Identifier: NCT02213458.


Assuntos
Demência , Medicare , Humanos , Idoso , Feminino , Estados Unidos , Ecossistema , Método Simples-Cego , Custos de Cuidados de Saúde , Demência/terapia
13.
Proc Natl Acad Sci U S A ; 106(6): 2018-22, 2009 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-19164761

RESUMO

Apolipoprotein epsilon4 (apoE4) has been strongly linked with Alzheimer's disease (AD) and contributes to several other neurological disorders. We investigated the influence of epsilon4 allele carrier status on the pattern of gray matter atrophy and disease severity in 51 patients with probable AD and 31 patients with behavioral variant frontotemporal dementia (bvFTD), compared with 56 healthy controls. Voxel-based morphometry was performed by using statistical parametric mapping. The epsilon4 allele frequency was higher in the AD group (P < 0.001) than the controls but not in the bvFTD group. No differences in demographic or cognitive profiles were observed between epsilon4 allele carriers and noncarriers within any of the diagnostic groups. However, epsilon4 carrier status was associated with more severe brain atrophy in disease-specific regions compared with noncarriers in both AD and bvFTD. AD epsilon4 carriers showed greater atrophy in the bilateral parietal cortex and right hippocampus, and bvFTD epsilon4 carriers demonstrated greater atrophy in the bilateral medial, dorsolateral, and orbital frontal cortex, anterior insula, and cingulate cortex with right predominance. This regional epsilon4 effect is consistent with the hypothesis that apoE may affect the morphologic expression uniquely in different neurodegenerative diseases. The atrophy patterns in epsilon4 carriers may indicate that they are at greater risk for clinical progression.


Assuntos
Doença de Alzheimer/patologia , Apolipoproteína E4/genética , Encéfalo/patologia , Demência/patologia , Lobo Temporal/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Atrofia , Mapeamento Encefálico , Estudos de Casos e Controles , Frequência do Gene , Hipocampo/patologia , Humanos , Pessoa de Meia-Idade , Lobo Parietal/patologia , Prognóstico
14.
Brain ; 133(Pt 2): 512-28, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20080878

RESUMO

Patients with early age-of-onset Alzheimer's disease show more rapid progression, more generalized cognitive deficits and greater cortical atrophy and hypometabolism compared to late-onset patients at a similar disease stage. The biological mechanisms that underlie these differences are not well understood. The purpose of this study was to examine in vivo whether metabolic differences between early-onset and late-onset Alzheimer's disease are associated with differences in the distribution and burden of fibrillar amyloid-beta. Patients meeting criteria for probable Alzheimer's disease (National Institute of Neurological and Communicative Disorders and Stroke and the Alzheimer's; Disease and Related Disorders Association criteria) were divided based on estimated age at first symptom (less than or greater than 65 years) into early-onset (n = 21, mean age-at-onset 55.2 +/- 5.9 years) and late-onset (n = 18, 72.0 +/- 4.7 years) groups matched for disease duration and severity. Patients underwent positron emission tomography with the amyloid-beta-ligand [(11)C]-labelled Pittsburgh compound-B and the glucose analogue [(18)F]-labelled fluorodeoxyglucose. A group of cognitively normal controls (n = 30, mean age 73.7 +/- 6.4) was studied for comparison. [(11)C]-labelled Pittsburgh compound-B images were analysed using Logan graphical analysis (cerebellar reference) and [(18)F]-labelled fluorodeoxyglucose images were normalized to mean activity in the pons. Group differences in tracer uptake were assessed on a voxel-wise basis using statistical parametric mapping, and by comparing mean values in regions of interest. To account for brain atrophy, analyses were repeated after applying partial volume correction to positron emission tomography data. Compared to normal controls, both early-onset and late-onset Alzheimer's disease patient groups showed increased [(11)C]-labelled Pittsburgh compound-B uptake throughout frontal, parietal and lateral temporal cortices and striatum on voxel-wise and region of interest comparisons (P < 0.05). However, there were no significant differences in regional or global [(11)C]-labelled Pittsburgh compound-B binding between early-onset and late-onset patients. In contrast, early-onset patients showed significantly lower glucose metabolism than late-onset patients in precuneus/posterior cingulate, lateral temporo-parietal and occipital corticies (voxel-wise and region of interest comparisons, P < 0.05). Similar results were found for [(11)C]-labelled Pittsburgh compound-B and [(18)F]-labelled fluorodeoxyglucose using atrophy-corrected data. Age-at-onset correlated positively with glucose metabolism in precuneus, lateral parietal and occipital regions of interest (controlling for age, education and Mini Mental State Exam, P < 0.05), while no correlations were found between age-at-onset and [(11)C]-labelled Pittsburgh compound-B binding. In summary, a comparable burden of fibrillar amyloid-beta was associated with greater posterior cortical hypometabolism in early-onset Alzheimer's disease. Our data are consistent with a model in which both early amyloid-beta accumulation and increased vulnerability to amyloid-beta pathology play critical roles in the pathogenesis of Alzheimer's disease in young patients.


Assuntos
Doença de Alzheimer/diagnóstico por imagem , Doença de Alzheimer/metabolismo , Peptídeos beta-Amiloides/metabolismo , Idoso , Idoso de 80 Anos ou mais , Doença de Alzheimer/patologia , Encéfalo/diagnóstico por imagem , Encéfalo/metabolismo , Encéfalo/patologia , Metabolismo Energético/fisiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Testes Neuropsicológicos , Tomografia por Emissão de Pósitrons/métodos , Compostos Radiofarmacêuticos/metabolismo
15.
Nat Neurosci ; 10(1): 77-86, 2007 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17159989

RESUMO

Transforming growth factor beta (TGFbeta) is a potent trophic factor for midbrain dopamine (DA) neurons, but its in vivo function and signaling mechanisms are not entirely understood. We show that the transcriptional cofactor homeodomain interacting protein kinase 2 (HIPK2) is required for the TGFbeta-mediated survival of mouse DA neurons. The targeted deletion of Hipk2 has no deleterious effect on the neurogenesis of DA neurons, but leads to a selective loss of these neurons that is due to increased apoptosis during programmed cell death. As a consequence, Hipk2(-/-) mutants show an array of psychomotor abnormalities. The function of HIPK2 depends on its interaction with receptor-regulated Smads to activate TGFbeta target genes. In support of this notion, DA neurons from Hipk2(-/-) mutants fail to survive in the presence of TGFbeta3 and Tgfbeta3(-/-) mutants show DA neuron abnormalities similar to those seen in Hipk2(-/-) mutants. These data underscore the importance of the TGFbeta-Smad-HIPK2 pathway in the survival of DA neurons and its potential as a therapeutic target for promoting DA neuron survival during neurodegeneration.


Assuntos
Proteínas de Transporte/fisiologia , Dopamina/metabolismo , Regulação da Expressão Gênica no Desenvolvimento/fisiologia , Mesencéfalo/citologia , Neurônios/fisiologia , Proteínas Serina-Treonina Quinases/fisiologia , Fator de Crescimento Transformador beta/fisiologia , Anfetamina/farmacologia , Análise de Variância , Animais , Animais Recém-Nascidos , Apoptose/fisiologia , Comportamento Animal , Benzazepinas/farmacologia , Calbindinas , Proteínas de Ligação ao Cálcio/metabolismo , Sobrevivência Celular/fisiologia , Células Cultivadas , Estimulantes do Sistema Nervoso Central/farmacologia , Agonistas de Dopamina/farmacologia , Embrião de Mamíferos , Proteínas de Homeodomínio/metabolismo , Imuno-Histoquímica , Camundongos , Camundongos Knockout , Atividade Motora/efeitos dos fármacos , Atividade Motora/genética , Proteínas do Tecido Nervoso/metabolismo , Proteínas Serina-Treonina Quinases/deficiência , Proteína G de Ligação ao Cálcio S100 , Fator de Crescimento Transformador beta/genética , Tirosina 3-Mono-Oxigenase/metabolismo
16.
Mol Neurobiol ; 58(11): 5857-5875, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34415487

RESUMO

Complement component 3 (C3) expression is increased in the cerebellum of aging mice that demonstrate locomotor impairments and increased excitatory synapse density. However, C3 regulation of locomotion, as well as C3 roles in excitatory synapse function, remains poorly understood. Here, we demonstrate that constitutive loss of C3 function in mice evokes a locomotor phenotype characterized by decreased speed, increased active state locomotor probability, and gait ataxia. C3 loss does not alter metabolism or body mass composition. No evidence of significant muscle weakness or degenerative arthritis was found in C3 knockout mice to explain decreased gait speeds. In an enriched primary cerebellar granule cell culture model, loss of C3 protein results in increased excitatory synaptic density and increased response to KCl depolarization. Our analysis of excitatory synaptic density in the cerebellar internal granule cell and molecular layers did not demonstrate increased synaptic density in vivo, suggesting the presence of compensatory mechanisms regulating synaptic development. Functional deficits in C3 knockout mice are therefore more likely to result from altered synaptic function and/or connectivity than gross synaptic deficits. Our data demonstrate a novel role for complement proteins in cerebellar regulation of locomotor output and control.


Assuntos
Cerebelo/patologia , Complemento C3/deficiência , Marcha Atáxica/etiologia , Proteínas do Tecido Nervoso/biossíntese , Sinapses/metabolismo , Animais , Apoptose , Composição Corporal , Cálcio/análise , Calorimetria Indireta , Células Cultivadas , Cerebelo/metabolismo , Complemento C3/fisiologia , Marcha Atáxica/metabolismo , Regulação da Expressão Gênica , Força da Mão , Articulação do Joelho/diagnóstico por imagem , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Proteínas do Tecido Nervoso/genética , Microtomografia por Raio-X
17.
J Neurosci ; 29(25): 8156-65, 2009 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-19553455

RESUMO

The impact of serotonergic neurotransmission on brain dopaminergic pathways has substantial relevance to many neuropsychiatric disorders. A particularly prominent role has been ascribed to the inhibitory effects of serotonin 2C receptor (5-HT(2C)R) activation on physiology and behavior mediated by the mesolimbic dopaminergic pathway, particularly in the terminal region of the nucleus accumbens. The influence of this receptor subtype on functions mediated by the nigrostriatal dopaminergic pathway is less clear. Here we report that a null mutation eliminating expression of 5-HT(2C)Rs produces marked alterations in the activity and functional output of this pathway. 5-HT(2C)R mutant mice displayed increased activity of substantia nigra pars compacta (SNc) dopaminergic neurons, elevated baseline extracellular dopamine concentrations in the dorsal striatum (DSt), alterations in grooming behavior, and enhanced sensitivity to the stereotypic behavioral effects of d-amphetamine and GBR 12909. These psychostimulant responses occurred in the absence of phenotypic differences in drug-induced extracellular dopamine concentration, suggesting a phenotypic alteration in behavioral responses to released dopamine. This was further suggested by enhanced behavioral responses of mutant mice to the D(1) receptor agonist SKF 81297. Differences in DSt D(1) or D(2) receptor expression were not found, nor were differences in medium spiny neuron firing patterns or intrinsic membrane properties following dopamine stimulation. We conclude that 5-HT(2C)Rs regulate nigrostriatal dopaminergic activity and function both at SNc dopaminergic neurons and at a locus downstream of the DSt.


Assuntos
Comportamento Animal/fisiologia , Corpo Estriado/fisiologia , Dopamina/metabolismo , Vias Neurais/fisiologia , Neurônios/fisiologia , Receptor 5-HT2C de Serotonina/fisiologia , Substância Negra/fisiologia , Anfetamina/administração & dosagem , Anfetamina/farmacologia , Animais , Autorradiografia , Comportamento Animal/efeitos dos fármacos , Benzazepinas/administração & dosagem , Benzazepinas/farmacologia , Corpo Estriado/efeitos dos fármacos , Corpo Estriado/metabolismo , Dopaminérgicos/administração & dosagem , Dopaminérgicos/farmacologia , Agonistas de Dopamina/administração & dosagem , Agonistas de Dopamina/farmacologia , Inibidores da Captação de Dopamina/administração & dosagem , Inibidores da Captação de Dopamina/farmacologia , Eletrofisiologia , Asseio Animal/fisiologia , Locomoção/fisiologia , Camundongos , Camundongos Endogâmicos C57BL , Mutação , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Piperazinas/administração & dosagem , Piperazinas/farmacologia , Receptor 5-HT2C de Serotonina/deficiência , Receptor 5-HT2C de Serotonina/genética , Comportamento Estereotipado/fisiologia , Substância Negra/efeitos dos fármacos , Substância Negra/metabolismo
18.
Alzheimers Dement (N Y) ; 6(1): e12017, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32548234

RESUMO

INTRODUCTION: Informal caregiving is an essential element of health-care delivery. Little data describes how caregivers structure care recipients' lives and impact their functional status. METHODS: We performed observational studies of community dwelling persons with dementia (PWD) to measure functional status by simultaneous assessment of physical activity (PA) and lifespace (LS). We present data from two caregiver/care-recipient dyads representing higher and average degrees of caregiver involvement. RESULTS: We acquired >42,800 (subject 1); >41,300 (subject 2) PA data points and >154,500 (subject 1); >119,700 (subject 2) LS data points over 15 months of near continuous observation. PA and LS patterns provided insights into the caregiver's role in structuring the PWD's day-to-day function and change in function over time. DISCUSSION: We show that device-enabled functional monitoring (FM) can successfully gather and display data at resolutions required for dementia care studies. Objective quantification of individual caregiver/care-recipient dyads provides opportunities to implement patient-centered care.

19.
Alzheimers Dement (N Y) ; 6(1): e12010, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32377557

RESUMO

INTRODUCTION: Many caregivers of people with dementia experience burden and resulting health effects due to the intensive nature of caregiving. Phone- and web-based care navigation is an innovative model of care that may be useful in addressing caregiver burden in dementia. METHODS: Qualitative methods (interviews, focus groups, and case study analysis) were used to identify care navigator approaches used to address caregiver burden in dementia as part of a dementia care navigation program. RESULTS: Care navigators targeted caregiver burden by focusing on strategies to reduce caregiver guilt and frustration, manage patient-related behavior, address caregiver depression, and improve the relationship between the caregiver and person with dementia. The case studies presented demonstrate the ways that care navigators identified patient and caregiver needs and tailored their approaches to meet the specific social, cultural, economic, and geographic contexts of the dyads with which they worked. DISCUSSION: Findings provide insights into strategies used to address caregiver burden through care navigation. Care navigators who speak the same language as the caregivers with whom they work and who have an in-depth understanding of the symptoms of different dementia syndromes may be particularly effective.

20.
Dementia (London) ; 19(6): 1955-1973, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30497302

RESUMO

OBJECTIVES: To illustrate specific psychosocial interventions aimed at improving self-efficacy among family caregivers enrolled in the Care Ecosystem, a model of navigated care designed to support persons with dementia and their primary caregivers. Enrolled family caregivers work with unlicensed care team navigators who are trained in dementia care and provide information, linkages to community resources, and emotional support by phone and email. METHOD: We conducted focus groups and interviews with the care team navigators to identify the approaches they used to target caregiver self-efficacy. We assessed mean self-efficacy scores in a sample of 780 family caregivers and selected three exemplary cases in which the caregivers had low self-efficacy scores at baseline with significantly higher scores after six months of participation in the Care Ecosystem intervention. RESULTS: Multiple psychosocial strategies were utilized by care team navigators working with patients with dementia and their family caregivers. Using thematic coding we identified three categories of Care Team Navigator intervention: emotional, informational, and instrumental support. These are consistent with a psychosocial approach to building self-efficacy. DISCUSSION: Self-efficacy represents a family caregiver's knowledge and preparedness in managing the challenges of care. Psychosocial support shows benefit in improving caregiver self-efficacy that in turn, may positively influence caregiver health and well-being. The findings in this manuscript demonstrate how a model of navigated care can positively impact self-efficacy among dementia family caregivers.


Assuntos
Cuidadores , Autoeficácia , Idoso , Cuidadores/psicologia , Demência/terapia , Feminino , Humanos , Masculino , Medicare , Estados Unidos
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