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1.
Br J Ophthalmol ; 106(3): 388-395, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-33243829

RESUMO

BACKGROUND/AIMS: To develop a convolutional neural network (CNN) to detect symptomatic Alzheimer's disease (AD) using a combination of multimodal retinal images and patient data. METHODS: Colour maps of ganglion cell-inner plexiform layer (GC-IPL) thickness, superficial capillary plexus (SCP) optical coherence tomography angiography (OCTA) images, and ultra-widefield (UWF) colour and fundus autofluorescence (FAF) scanning laser ophthalmoscopy images were captured in individuals with AD or healthy cognition. A CNN to predict AD diagnosis was developed using multimodal retinal images, OCT and OCTA quantitative data, and patient data. RESULTS: 284 eyes of 159 subjects (222 eyes from 123 cognitively healthy subjects and 62 eyes from 36 subjects with AD) were used to develop the model. Area under the receiving operating characteristic curve (AUC) values for predicted probability of AD for the independent test set varied by input used: UWF colour AUC 0.450 (95% CI 0.282, 0.592), OCTA SCP 0.582 (95% CI 0.440, 0.724), UWF FAF 0.618 (95% CI 0.462, 0.773), GC-IPL maps 0.809 (95% CI 0.700, 0.919). A model incorporating all images, quantitative data and patient data (AUC 0.836 (CI 0.729, 0.943)) performed similarly to models only incorporating all images (AUC 0.829 (95% CI 0.719, 0.939)). GC-IPL maps, quantitative data and patient data AUC 0.841 (95% CI 0.739, 0.943). CONCLUSION: Our CNN used multimodal retinal images to successfully predict diagnosis of symptomatic AD in an independent test set. GC-IPL maps were the most useful single inputs for prediction. Models including only images performed similarly to models also including quantitative data and patient data.


Assuntos
Doença de Alzheimer , Doença de Alzheimer/diagnóstico por imagem , Angiofluoresceinografia/métodos , Humanos , Redes Neurais de Computação , Retina/diagnóstico por imagem , Vasos Retinianos , Tomografia de Coerência Óptica/métodos
2.
Lancet Neurol ; 20(7): 537-547, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34146512

RESUMO

BACKGROUND: The identification of people at risk of cognitive impairment is essential for improving recruitment in secondary prevention trials of Alzheimer's disease. We aimed to test and qualify a biomarker risk assignment algorithm (BRAA) to identify participants at risk of developing mild cognitive impairment due to Alzheimer's disease within 5 years, and to evaluate the safety and efficacy of low-dose pioglitazone to delay onset of mild cognitive impairment in these at-risk participants. METHODS: In this phase 3, multicentre, randomised, double-blind, placebo-controlled, parallel-group study, we enrolled cognitively healthy, community living participants aged 65-83 years from 57 academic affiliated and private research clinics in Australia, Germany, Switzerland, the UK, and the USA. By use of the BRAA, participants were grouped as high risk or low risk. Participants at high risk were randomly assigned 1:1 to receive oral pioglitazone (0·8 mg/day sustained release) or placebo, and all low-risk participants received placebo. Study investigators, site staff, sponsor personnel, and study participants were masked to genotype, risk assignment, and treatment assignment. The planned study duration was the time to accumulate 202 events of mild cognitive impairment due to Alzheimer's disease in White participants who were at high risk (the population on whom the genetic analyses that informed the BRAA development was done). Primary endpoints were time-to-event comparisons between participants at high risk and low risk given placebo (for the BRAA objective), and between participants at high risk given pioglitazone or placebo (for the efficacy objective). The primary analysis included all participants who were randomly assigned, received at least one dose of study drug, and had at least one valid post-baseline visit, with significance set at p=0·01. The safety analysis included all participants who were randomly assigned and received at least one dose of study medication. An efficacy futility analysis was planned for when approximately 33% of the anticipated events occurred in the high-risk, White, non-Hispanic or Latino group. This trial is registered with ClinicalTrials.gov, NCT01931566. FINDINGS: Between Aug 28, 2013, and Dec 21, 2015, we enrolled 3494 participants (3061 at high risk and 433 at low risk). Of those participants, 1545 were randomly assigned to pioglitazone and 1516 to placebo. 1104 participants discontinued treatment (464 assigned to the pioglitazone group, 501 in the placebo high risk group, and 139 in the placebo low risk group). 3399 participants had at least one dose of study drug or placebo and at least one post-baseline follow-up visit, and were included in the efficacy analysis. 3465 participants were included in the safety analysis (1531 assigned to the pioglitazone group, 1507 in the placebo high risk group, and 427 in the placebo low risk group). In the full analysis set, 46 (3·3%) of 1406 participants at high risk given placebo had mild cognitive impairment due to Alzheimer's disease, versus four (1·0%) of 402 participants at low risk given placebo (hazard ratio 3·26, 99% CI 0·85-12·45; p=0·023). 39 (2·7%) of 1430 participants at high risk given pioglitazone had mild cognitive impairment, versus 46 (3·3%) of 1406 participants at high risk given placebo (hazard ratio 0·80, 99% CI 0·45-1·40; p=0·307). In the safety analysis set, seven (0·5%) of 1531 participants at high risk given pioglitazone died versus 21 (1·4%) of 1507 participants at high risk given placebo. There were no other notable differences in adverse events between groups. The study was terminated in January, 2018, after failing to meet the non-futility threshold. INTERPRETATION: Pioglitazone did not delay the onset of mild cognitive impairment. The biomarker algorithm demonstrated a 3 times enrichment of events in the high risk placebo group compared with the low risk placebo group, but did not reach the pre-specified significance threshold. Because we did not complete the study as planned, findings can only be considered exploratory. The conduct of this study could prove useful to future clinical development strategies for Alzheimer's disease prevention studies. FUNDING: Takeda and Zinfandel.


Assuntos
Disfunção Cognitiva/tratamento farmacológico , Pioglitazona/uso terapêutico , Medição de Risco/métodos , Idoso , Idoso de 80 Anos ou mais , Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/metabolismo , Biomarcadores Farmacológicos , Disfunção Cognitiva/metabolismo , Método Duplo-Cego , Feminino , Humanos , Masculino , Pioglitazona/metabolismo , Prognóstico , Fatores de Risco , Resultado do Tratamento
3.
Ophthalmic Surg Lasers Imaging Retina ; 52(6): 336-344, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-34185588

RESUMO

BACKGROUND AND OBJECTIVE: To evaluate retinal microvascular changes in early and late-onset Alzheimer's disease (AD). PATIENTS AND METHODS: Eighty-six eyes of 50 late-onset AD participants, 27 eyes of 15 early onset AD participants, and 111 eyes of 57 cognitively normal controls were included. Optical coherence tomography angiography (OCTA) vessel density (VD) and perfusion density (PD) in Early Treatment Diabetic Retinopathy Study 3-mm and 6-mm circles and rings were assessed. RESULTS: There was decreased PD in early onset AD 3-mm circle (P = .026) and ring (P = .026) versus controls as well as in late-onset AD 3-mm circle (P = .023) and ring (P = .023) versus controls. There was decreased VD in late-onset AD 3-mm circle (P = .012) and ring (P = .006). No parameters differed between early and late-onset AD (P > .05). CONCLUSIONS: AD eyes exhibited decreased retinal microvascular density compared to controls. Retinal parameters may not differ between early onset AD and late-onset AD after adjusting for age. [Ophthalmic Surg Lasers Imaging Retina. 2021;52:336-344.].


Assuntos
Doença de Alzheimer , Retinopatia Diabética , Doença de Alzheimer/diagnóstico , Angiofluoresceinografia , Humanos , Microvasos , Retina/diagnóstico por imagem , Vasos Retinianos , Tomografia de Coerência Óptica
4.
J Med Chem ; 64(1): 677-694, 2021 01 14.
Artigo em Inglês | MEDLINE | ID: mdl-33370104

RESUMO

A search for structurally diversified Tyk2 JH2 ligands from 6 (BMS-986165), a pyridazine carboxamide-derived Tyk2 JH2 ligand as a clinical Tyk2 inhibitor currently in late development for the treatment of psoriasis, began with a survey of six-membered heteroaryl groups in place of the N-methyl triazolyl moiety in 6. The X-ray co-crystal structure of an early lead (12) revealed a potential new binding pocket. Exploration of the new pocket resulted in two frontrunners for a clinical candidate. The potential hydrogen bonding interaction with Thr599 in the pocket was achieved with a tertiary amide moiety, confirmed by the X-ray co-crystal structure of 29. When the diversity search was extended to nicotinamides, a single fluorine atom addition was found to significantly enhance the permeability, which directly led to the discovery of 7 (BMS-986202) as a clinical Tyk2 inhibitor that binds to Tyk2 JH2. The preclinical studies of 7, including efficacy studies in mouse models of IL-23-driven acanthosis, anti-CD40-induced colitis, and spontaneous lupus, will also be presented.


Assuntos
Ciclopropanos/farmacologia , Descoberta de Drogas , Oxazóis/farmacologia , Inibidores de Proteínas Quinases/farmacologia , TYK2 Quinase/antagonistas & inibidores , Animais , Catálise , Cristalografia por Raios X , Ciclopropanos/química , Humanos , Camundongos , Oxazóis/química , Ligação Proteica , Inibidores de Proteínas Quinases/química , Psoríase/tratamento farmacológico , Relação Estrutura-Atividade , TYK2 Quinase/metabolismo
5.
J Med Chem ; 63(23): 15050-15071, 2020 12 10.
Artigo em Inglês | MEDLINE | ID: mdl-33261314

RESUMO

Scaffold hopping and structure-based drug design were employed to identify substituted 4-aminoquinolines and 4-aminonaphthyridines as potent, small molecule inhibitors of tumor necrosis factor alpha (TNFα). Structure-activity relationships in both the quinoline and naphthyridine series leading to the identification of compound 42 with excellent potency and pharmacokinetic profile are discussed. X-ray co-crystal structure analysis and ultracentrifugation experiments clearly demonstrate that these inhibitors distort the TNFα trimer upon binding, leading to aberrant signaling when the trimer binds to TNF receptor 1 (TNFR1). Pharmacokinetic-pharmacodynamic activity of compound 42 in a TNF-induced IL-6 mouse model and in vivo activity in a collagen antibody-induced arthritis model, where it showed biologic-like in vivo efficacy, will be discussed.


Assuntos
Naftiridinas/farmacologia , Quinolinas/farmacologia , Fator de Necrose Tumoral alfa/antagonistas & inibidores , Animais , Artrite Experimental/tratamento farmacológico , Artrite Reumatoide/tratamento farmacológico , Desenho de Fármacos , Feminino , Humanos , Camundongos Endogâmicos C57BL , Microssomos Hepáticos/metabolismo , Estrutura Molecular , Naftiridinas/síntese química , Naftiridinas/farmacocinética , Naftiridinas/uso terapêutico , Estudo de Prova de Conceito , Quinolinas/síntese química , Quinolinas/farmacocinética , Quinolinas/uso terapêutico , Relação Estrutura-Atividade , Fator de Necrose Tumoral alfa/metabolismo
6.
Ophthalmic Surg Lasers Imaging Retina ; 51(12): 706-714, 2020 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-33339052

RESUMO

BACKGROUND AND OBJECTIVE: To evaluate the association of changes in retinal anatomy and microvasculature with age and sex in cognitively healthy older adults. PATIENTS AND METHODS: Cross-sectional study of cognitively healthy subjects aged 50 years and older who underwent optical coherence tomography angiography (OCTA) to estimate the association between age and sex with ganglion cell layer-inner plexiform layer (GC-IPL); central subfield thickness (CST); subfoveal choroidal thickness (CT); foveal avascular zone (FAZ) size; and superficial (SCP), deep (DCP), and whole capillary plexus (WCP) vessel density (VD) and perfusion density (PD) measured in the ETDRS 3-mm and 6-mm circle and rings. RESULTS: Among 141 older adults (72.9% female; median age: 69 years), 282 eyes were imaged. Females had a greater CT, GC-IPL thickness, and FAZ size and a lower CST than males. After controlling for sex, both CT (P = .001) and GC-IPL thickness (P < .001) decreased with age, whereas FAZ size and CST did not. There was a reduction in VD and PD in SCP, DCP, and WCP with age in the 3-mm circle, 3-mm ring, and 6-mm circle (all P < .05). CONCLUSIONS: There is a significant reduction in both VD and PD, as well as decreased choroidal and GC-IPL thickness associated with aging, even beyond the fifth decade, in cognitively healthy adults. [Ophthalmic Surg Lasers Imaging Retina. 2020;51:706-714.].


Assuntos
Macula Lutea , Tomografia de Coerência Óptica , Fatores Etários , Idoso , Estudos Transversais , Feminino , Angiofluoresceinografia , Humanos , Masculino , Pessoa de Meia-Idade , Vasos Retinianos/diagnóstico por imagem
7.
ACS Med Chem Lett ; 11(11): 2195-2203, 2020 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-33214829

RESUMO

Bruton's tyrosine kinase (BTK) has been shown to play a key role in the pathogenesis of autoimmunity. Therefore, the inhibition of the kinase activity of BTK with a small molecule inhibitor could offer a breakthrough in the clinical treatment of many autoimmune diseases. This Letter describes the discovery of BMS-986143 through systematic structure-activity relationship (SAR) development. This compound benefits from defined chirality derived from two rotationally stable atropisomeric axes, providing a potent and selective single atropisomer with desirable efficacy and tolerability profiles.

8.
J Alzheimers Dis ; 77(4): 1793-1803, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32925039

RESUMO

BACKGROUND: Previous studies have demonstrated that aerobic exercise (AE) and the Dietary Approaches to Stop Hypertension (DASH) diet can improve neurocognition. However, the mechanisms by which lifestyle improves neurocognition have not been widely studied. We examined the associations between changes in metabolic, neurotrophic, and inflammatory biomarkers with executive functioning among participants from the Exercise and Nutritional Interventions for Neurocognitive Health Enhancement (ENLIGHTEN) trial. OBJECTIVE: To examine the association between changes in metabolic function and neurocognition among older adults with cognitive impairment, but without dementia (CIND) participating in a comprehensive lifestyle intervention. METHODS: ENLIGHTEN participants were randomized using a 2×2 factorial design to receive AE, DASH, both AE+DASH, or a health education control condition (HE) for six months. Metabolic biomarkers included insulin resistance (homeostatic model assessment [HOMA-IR]), leptin, and insulin-like growth factor (IGF-1); neurotrophic biomarkers included brain derived neurotrophic factor (BDNF) and vascular endothelial growth factor (VEGF); and inflammatory biomarkers included interleukin-6 (IL-6) and C-Reactive Protein (CRP). RESULTS: Participants included 132 sedentary older adults (mean age = 65 [SD = 7]) with CIND. Results demonstrated that both AE (d = 0.48, p = 0.015) and DASH improved metabolic function (d = 0.37, p = 0.039), without comparable improvements in neurotrophic or inflammatory biomarkers. Greater improvements in metabolic function, including reduced HOMA-IR (B = -2.3 [-4.3, -0.2], p = 0.033) and increased IGF-1 (B = 3.4 [1.2, 5.7], p = 0.004), associated with increases in Executive Function. CONCLUSION: Changes in neurocognition after lifestyle modification are associated with improved metabolic function.


Assuntos
Disfunção Cognitiva/metabolismo , Abordagens Dietéticas para Conter a Hipertensão/tendências , Exercício Físico/fisiologia , Comportamento de Redução do Risco , Comportamento Sedentário , Idoso , Biomarcadores/metabolismo , Disfunção Cognitiva/prevenção & controle , Disfunção Cognitiva/psicologia , Registros de Dieta , Dieta Saudável/psicologia , Dieta Saudável/tendências , Abordagens Dietéticas para Conter a Hipertensão/psicologia , Exercício Físico/psicologia , Teste de Esforço/psicologia , Teste de Esforço/tendências , Feminino , Humanos , Masculino , Testes de Estado Mental e Demência , Pessoa de Meia-Idade , Estado Nutricional/fisiologia
9.
Med Care ; 58(9): 842-849, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32826749

RESUMO

BACKGROUND: The CAregiver Perceptions About CommunIcaTion with Clinical Team members (CAPACITY) instrument measures how care partners perceive themselves to be supported by the patient's health care team and their experiences communicating with the team. OBJECTIVES: The objective of this study was to assess the measurement properties (ie, structural validity of the construct and internal consistency) of the CAPACITY instrument in care partners of patients with cognitive impairment, and to examine whether care partner health literacy and patient cognitive impairment are associated with a higher or lower CAPACITY score. RESEARCH DESIGN: This was a retrospective cohort study. SUBJECTS: A total of 1746 dyads of community-dwelling care partners and older adults in the United States with cognitive impairment who obtained an amyloid positron emission tomography scan. MEASURES: The CAPACITY instrument comprises 12 items that can be combined as a total score or examined as subdomain scores about communication with the team and care partner capacity-assessment by the team. The 2 covariates of primary interest in the regression model are health literacy and level of cognitive impairment of the patient (Modified Telephone Interview Cognitive Status). RESULTS: Confirmatory factor analysis showed the CAPACITY items fit the expected 2-factor structure (communication and capacity). Higher cognitive functioning of patients and higher health literacy among care partners was associated with lower communication domain scores, lower capacity domain scores, and lower overall CAPACITY scores. CONCLUSIONS: The strong psychometric validity of the CAPACITY measure indicates it could have utility in other family caregivers or care partner studies assessing the quality of interactions with clinical teams. Knowing that CAPACITY differs by care partner health literacy and patient impairment level may help health care teams employ tailored strategies to achieve high-quality care partner interactions.


Assuntos
Cuidadores/psicologia , Disfunção Cognitiva/epidemiologia , Comunicação , Pesquisas sobre Serviços de Saúde/normas , Letramento em Saúde/estatística & dados numéricos , Equipe de Assistência ao Paciente/organização & administração , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Análise Fatorial , Feminino , Nível de Saúde , Humanos , Masculino , Psicometria , Reprodutibilidade dos Testes , Estudos Retrospectivos , Índice de Gravidade de Doença , Fatores Sexuais , Fatores Socioeconômicos
10.
Alzheimers Dement ; 16(8): 1107-1114, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32543781

RESUMO

INTRODUCTION: The Alzheimer's Disease Prevention Registry (ADPR) of the Joseph and Kathleen Bryan Alzheimer's Disease Research Center at Duke University has been successful in achieving a racially diverse and "research ready" cohort of cognitively healthy volunteers. METHODS: The ADPR is based on an infrastructure that includes: (1) an administrative leadership team; (2) a coordinating center; (3) an IT management team; (4) a community engagement team; and (5) collaborations with study partners across disciplines. RESULTS: The ADPR currently has more than 4677 members, 26% of whom are African American. The ADPR has supported 21 studies including 8 biomarker studies, 7 clinical trials, 4 cognitive neuroscience studies, and 2 studies assessing novel computerized measures. DISCUSSION: We describe our experiences establishing and maintaining a diverse ADPR as well as insights on recruitment strategies to increase the representation of African Americans in Alzheimer's disease studies.


Assuntos
Afro-Americanos , Doença de Alzheimer , Seleção de Pacientes , Sistema de Registros , Feminino , Voluntários Saudáveis , Humanos , Masculino
11.
J Alzheimers Dis ; 74(2): 625-636, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32065790

RESUMO

BACKGROUND: Amyloid-ß PET scans will likely become an integral part of the diagnostic evaluation for Alzheimer's disease if Medicare approves reimbursement for the scans. However, little is known about patients' and their care partners' interpretation of scan results. OBJECTIVE: This study seeks to understand how accurately patients with mild cognitive impairment (MCI) or dementia and their care partners report results of amyloid-ß PET scans and factors related to correct reporting. METHODS: A mixed-methods approach was used to analyze survey data from 1,845 patient-care partner dyads and responses to open-ended questions about interpretation of scan results from a sub-sample of 200 dyads. RESULTS: Eighty-three percent of patients and 85% of care partners correctly reported amyloid-ß PET scan results. Patients' higher cognitive function was associated with a small but significant decrease in the predicted probability of not only patients accurately reporting scan results (ME: -0.004, 95% CI: -0.007, -0.000), but also care partners accurately reporting scan results (ME: -0.006, 95% CI: -0.007, -0.001), as well as decreased concordance between patient and care partner reports (ME: -0.004, 95% CI: -0.007, -0.001). Content analysis of open-ended responses found that participants who reported the scan results incorrectly exhibited more confusion about diagnostic terminology than those who correctly reported the scan results. CONCLUSION: Overall, patients with MCI or dementia showed high rates of accurate reporting of amyloid-ß PET scan results. However, responses to questions about the meaning of the scan results highlight the need for improved provider communication, including providing written explanations and better prognostic information.


Assuntos
Doença de Alzheimer/psicologia , Peptídeos beta-Amiloides , Cuidadores/psicologia , Disfunção Cognitiva/psicologia , Participação do Paciente/psicologia , Tomografia por Emissão de Pósitrons/psicologia , Idoso , Idoso de 80 Anos ou mais , Doença de Alzheimer/diagnóstico por imagem , Doença de Alzheimer/metabolismo , Peptídeos beta-Amiloides/metabolismo , Cuidadores/normas , Disfunção Cognitiva/diagnóstico por imagem , Disfunção Cognitiva/metabolismo , Estudos de Coortes , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Tomografia por Emissão de Pósitrons/normas
12.
J Am Geriatr Soc ; 68(3): 559-568, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31755550

RESUMO

OBJECTIVES: To evaluate the longer term changes in executive functioning among participants with cardiovascular disease (CVD) risk factors and cognitive impairments with no dementia (CIND) randomized to a diet and exercise intervention. DESIGN: A 2 (Exercise) × 2 (Dietary Approaches to Stop Hypertension [DASH] eating plan) factorial randomized clinical trial. SETTING: Academic tertiary care medical center. PARTICIPANTS: Volunteer sample of 160 older sedentary adults with CIND and at least one additional CVD risk factor enrolled in the ENLIGHTEN trial between December 2011 and March 2016. INTERVENTIONS: Six months of aerobic exercise (AE), DASH diet counseling, combined AE + DASH, or health education (HE) controls. MEASUREMENTS: Neurocognitive battery recommended by the Neuropsychological Working Group for Vascular Cognitive Disorders including measures of executive function, memory, and language/verbal fluency. Secondary outcomes included the Clinical Dementia Rating-Sum of Boxes (CDR-SB), Six-Minute Walk Distance (6MWD), and CVD risk including blood pressure, body weight, and CVD medication burden. RESULTS: Despite discontinuation of lifestyle changes, participants in the exercise groups retained better executive function 1 year post-intervention (P = .041) compared with non-exercise groups, with a similar, albeit weaker, pattern in the DASH groups (P = .054), without variation over time (P's > .867). Participants in the exercise groups also achieved greater sustained improvements in 6MWD compared with non-Exercise participants (P < .001). Participants in the DASH groups exhibited lower CVD risk relative to non-DASH participants (P = .032); no differences in CVD risk were observed for participants in the Exercise groups compared with non-Exercise groups (P = .711). In post hoc analyses, the AE + DASH group had better performance on executive functioning (P < .001) and CDR-SB (P = .011) compared with HE controls. CONCLUSION: For participants with CIND and CVD risk factors, exercise for 6 months promoted better executive functioning compared with non-exercisers through 1-year post-intervention, although its clinical significance is uncertain. J Am Geriatr Soc 68:559-568, 2020.


Assuntos
Cognição , Abordagens Dietéticas para Conter a Hipertensão , Exercício Físico/fisiologia , Tempo , Idoso , Pressão Sanguínea/fisiologia , Doenças Cardiovasculares/prevenção & controle , Doenças Cardiovasculares/terapia , Função Executiva/fisiologia , Feminino , Seguimentos , Educação em Saúde , Humanos , Masculino , Pessoa de Meia-Idade
13.
Ophthalmic Surg Lasers Imaging Retina ; 50(11): 709-718, 2019 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-31755970

RESUMO

BACKGROUD AND OBJECTIVE: To evaluate the relationship between retinal microvascular parameters on optical coherence tomography angiography (OCTA) and neurodegenerative changes assessed by measurement of brain volume on volumetric magnetic resonance imaging (MRI) in Alzheimer's disease (AD) and mild cognitive impairment (MCI). PATIENTS AND METHODS: Sixteen subjects with AD and MCI underwent OCTA imaging (3 mm × 3 mm and 6 mm × 6 mm scans) and volumetric brain MRI imaging with automated volumetric segmentation and quantification. Spearman's correlation (ρ) was performed between forebrain parenchyma, cortical gray matter, inferolateral ventricle (ILV), lateral ventricle (LV), and hippocampus (HP) MRI volumes and vessel density (VD), along with perfusion density (PD) for the 6-mm circle, 6-mm ring, 3-mm circle, and 3-mm ring Early Treatment Diabetic Retinopathy Study regions of the superficial capillary plexus. RESULTS: Thirty eyes of 16 patients (seven MCI and nine AD) with good-quality OCTA images were analyzed. ILV volume inversely correlated with the VD in the 6-mm circle (ρ = -0 .565, P = .028) and 3-mm ring (ρ = -0.569, P = .027) and PD in the 3-mm ring (ρ = -0.605, P = .0169). Forebrain, cortical gray matter, LV, and HP volumes did not significantly correlate with either VD or PD (P > .05). CONCLUSIONS: In this pilot investigation, the authors found a significant correlation between reduction in the superficial capillary plexus VD and PD on OCTA and expansion of the ILV in MCI and AD. This relationship between the retinal microvasculature and cerebral volumetric changes deserves further investigation. [Ophthalmic Surg Lasers Imaging Retina. 2019;50:709-718.].


Assuntos
Doença de Alzheimer/patologia , Encéfalo/patologia , Disfunção Cognitiva/patologia , Vasos Retinianos/patologia , Idoso , Idoso de 80 Anos ou mais , Estudos Transversais , Feminino , Angiofluoresceinografia/métodos , Humanos , Imageamento por Ressonância Magnética , Masculino , Microvasos/patologia , Pessoa de Meia-Idade , Projetos Piloto , Fluxo Sanguíneo Regional , Tomografia de Coerência Óptica/métodos
14.
Alzheimers Dement (N Y) ; 5: 254-263, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31304231

RESUMO

Introduction: Mitochondrial dysfunction is implicated in the pathophysiology of Alzheimer's disease (AD). Accordingly, drugs that positively influence mitochondrial function are being evaluated in delay-of-onset clinical trials with at-risk individuals. Such ongoing clinical research can be advanced by developing a better understanding of how these drugs affect intermediate brain phenotypes associated with both AD risk and pathophysiology. Methods: Using a randomized, parallel-group, placebo-controlled design in 55 healthy elderly volunteers, we explored the effects of oral, low-dose pioglitazone, a thiazolidinedione with promitochondrial effects, on hippocampal activity measured with functional magnetic resonance imaging during the encoding of novel face-name pairs. Results: Compared with placebo, 0.6 mg of pioglitazone (but not 2.1 mg, 3.9 mg, or 6.0 mg) administered daily for 14 days was associated with significant increases in right hippocampal activation during encoding of novel face-name pairs at day 7 and day 14, relative to baseline. Discussion: Our exploratory analyses suggest that low-dose pioglitazone has measurable effects on mnemonic brain function associated with AD risk and pathophysiology.

15.
J Med Chem ; 62(20): 8973-8995, 2019 10 24.
Artigo em Inglês | MEDLINE | ID: mdl-31318208

RESUMO

Small molecule JAK inhibitors have emerged as a major therapeutic advancement in treating autoimmune diseases. The discovery of isoform selective JAK inhibitors that traditionally target the catalytically active site of this kinase family has been a formidable challenge. Our strategy to achieve high selectivity for TYK2 relies on targeting the TYK2 pseudokinase (JH2) domain. Herein we report the late stage optimization efforts including a structure-guided design and water displacement strategy that led to the discovery of BMS-986165 (11) as a high affinity JH2 ligand and potent allosteric inhibitor of TYK2. In addition to unprecedented JAK isoform and kinome selectivity, 11 shows excellent pharmacokinetic properties with minimal profiling liabilities and is efficacious in several murine models of autoimmune disease. On the basis of these findings, 11 appears differentiated from all other reported JAK inhibitors and has been advanced as the first pseudokinase-directed therapeutic in clinical development as an oral treatment for autoimmune diseases.


Assuntos
Doenças Autoimunes/tratamento farmacológico , Descoberta de Drogas , Compostos Heterocíclicos/farmacologia , Inibidores de Proteínas Quinases/farmacologia , TYK2 Quinase/antagonistas & inibidores , Regulação Alostérica/efeitos dos fármacos , Animais , Cristalografia por Raios X , Compostos Heterocíclicos/química , Compostos Heterocíclicos/farmacocinética , Compostos Heterocíclicos/uso terapêutico , Humanos , Camundongos , Inibidores de Proteínas Quinases/química , Inibidores de Proteínas Quinases/farmacocinética , Inibidores de Proteínas Quinases/uso terapêutico
16.
Sci Transl Med ; 11(502)2019 07 24.
Artigo em Inglês | MEDLINE | ID: mdl-31341059

RESUMO

TYK2 is a nonreceptor tyrosine kinase involved in adaptive and innate immune responses. A deactivating coding variant has previously been shown to prevent receptor-stimulated activation of this kinase and provides high protection from several common autoimmune diseases but without immunodeficiency. An agent that recapitulates the phenotype of this deactivating coding variant may therefore represent an important advancement in the treatment of autoimmunity. BMS-986165 is a potent oral agent that similarly blocks receptor-stimulated activation of TYK2 allosterically and with high selectivity and potency afforded through optimized binding to a regulatory domain of the protein. Signaling and functional responses in human TH17, TH1, B cells, and myeloid cells integral to autoimmunity were blocked by BMS-986165, both in vitro and in vivo in a phase 1 clinical trial. BMS-986165 demonstrated robust efficacy, consistent with blockade of multiple autoimmune pathways, in murine models of lupus nephritis and inflammatory bowel disease, supporting its therapeutic potential for multiple immune-mediated diseases.


Assuntos
Autoimunidade/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , TYK2 Quinase/química , Animais , Feminino , Voluntários Saudáveis , Compostos Heterocíclicos/farmacologia , Humanos , Interferon alfa-2/farmacologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos SCID , Inibidores de Proteínas Quinases/farmacologia , TYK2 Quinase/antagonistas & inibidores
17.
J Med Chem ; 62(20): 8953-8972, 2019 10 24.
Artigo em Inglês | MEDLINE | ID: mdl-31314518

RESUMO

As a member of the Janus (JAK) family of nonreceptor tyrosine kinases, TYK2 plays an important role in mediating the signaling of pro-inflammatory cytokines including IL-12, IL-23, and type 1 interferons. The nicotinamide 4, identified by a SPA-based high-throughput screen targeting the TYK2 pseudokinase domain, potently inhibits IL-23 and IFNα signaling in cellular assays. The described work details the optimization of this poorly selective hit (4) to potent and selective molecules such as 47 and 48. The discoveries described herein were critical to the eventual identification of the clinical TYK2 JH2 inhibitor (see following report in this issue). Compound 48 provided robust inhibition in a mouse IL-12-induced IFNγ pharmacodynamic model as well as efficacy in an IL-23 and IL-12-dependent mouse colitis model. These results demonstrate the ability of TYK2 JH2 domain binders to provide a highly selective alternative to conventional TYK2 orthosteric inhibitors.


Assuntos
Niacinamida/análogos & derivados , Ácidos Nicotínicos/farmacologia , Inibidores de Proteínas Quinases/farmacologia , TYK2 Quinase/antagonistas & inibidores , Regulação Alostérica , Animais , Humanos , Ligantes , Camundongos , Niacinamida/metabolismo , Niacinamida/farmacologia , Ácidos Nicotínicos/metabolismo , Inibidores de Proteínas Quinases/metabolismo , Relação Estrutura-Atividade
18.
Ophthalmol Retina ; 3(6): 489-499, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31174670

RESUMO

PURPOSE: Evaluate and compare the retinal microvasculature in the superficial capillary plexus (SCP) in Alzheimer's disease (AD), mild cognitive impairment (MCI), and cognitively intact controls using OCT angiography. OCT parameters were also compared. DESIGN: Cross-sectional study. PARTICIPANTS: Seventy eyes from 39 AD participants, 72 eyes from 37 MCI participants, and 254 eyes from 133 control participants were enrolled. METHODS: Participants were imaged using Zeiss Cirrus HD-5000 with AngioPlex (Carl Zeiss Meditec, Dublin, CA) and underwent cognitive evaluation with Mini-Mental State Examination. MAIN OUTCOME MEASURES: Vessel density (VD) and perfusion density (PD) in the SCP within the Early Treatment Diabetic Retinopathy Study 6-mm circle, 3-mm circle, and 3-mm ring were compared between groups. Foveal avascular zone (FAZ) area, central subfield thickness (CST), macular ganglion cell-inner plexiform layer (GC-IPL) thickness, and peripapillary retinal nerve fiber layer (RNFL) thickness were also compared. RESULTS: Alzheimer's participants showed significantly decreased SCP VD and PD in the 3-mm ring (P = 0.001 and P = 0.002, respectively) and 3-mm circle (P = 0.003 and P = 0.004, respectively) and decreased SCP VD in the 6-mm circle (P = 0.047) compared with MCI and significantly decreased SCP VD and PD in the 3-mm ring (P = 0.008 and P = 0.004, respectively) and 3-mm circle (P = 0.015 and P = 0.009, respectively) and SCP PD in the 6-mm circle (P = 0.033) when compared with cognitively intact controls. There was no difference in SCP VD or PD between MCI and controls (P > 0.05). FAZ area and CST did not differ significantly between groups (P > 0.05). Alzheimer's participants showed significantly decreased GC-IPL thickness over the inferior (P = 0.032) and inferonasal (P = 0.025) sectors compared with MCI and significantly decreased GC-IPL thickness over the entire (P = 0.012), superonasal (P = 0.041), inferior (P = 0.004), and inferonasal (P = 0.006) sectors compared to controls. MCI participants showed significantly decreased temporal RNFL thickness (P = 0.04) compared with controls. CONCLUSIONS: Alzheimer's participants showed significantly reduced macular VD, PD, and GC-IPL thickness compared with MCI and controls. Changes in the retinal microvasculature may mirror small vessel cerebrovascular changes in AD.


Assuntos
Doença de Alzheimer/complicações , Disfunção Cognitiva/complicações , Angiofluoresceinografia/métodos , Microvasos/patologia , Degeneração Retiniana/diagnóstico , Vasos Retinianos/patologia , Tomografia de Coerência Óptica/métodos , Idoso , Doença de Alzheimer/diagnóstico , Doença de Alzheimer/fisiopatologia , Circulação Cerebrovascular , Disfunção Cognitiva/diagnóstico , Disfunção Cognitiva/fisiopatologia , Estudos Transversais , Feminino , Fundo de Olho , Humanos , Masculino , Fibras Nervosas/patologia , Neuroimagem/métodos , Degeneração Retiniana/etiologia , Células Ganglionares da Retina/patologia , Acuidade Visual
19.
Anal Chem ; 91(13): 8443-8452, 2019 07 02.
Artigo em Inglês | MEDLINE | ID: mdl-31247719

RESUMO

We report a novel immunocapture (IC)-LC-MS/MS methodology to directly measure real time in vivo receptor occupancy (RO) for a covalent binding drug in blood lysate. A small molecule quencher was added immediately after sample collection to convert the free receptor to a quencher-bound receptor (QB-R) which was measured with the drug-bound receptor (DB-R) simultaneously by LC-MS/MS after immunocapture enrichment, followed by trypsin digestion. Addition of the quencher is necessary to prevent the free receptor from ex vivo binding with the drug. The real time RO was calculated based on the concentrations of DB-R and the free receptor (which is now QB-R) that were obtained from each sample. This strategy has been successfully applied to the measurement of the RO for Bruton's tyrosine kinase (BTK) in the blood lysate of monkeys after dosing with branebrutinib (BMS-986195), a covalent BTK inhibitor being evaluated to treat rheumatoid arthritis. A custom-made quencher, which is more reactive to BTK than branebrutinib, was added in excess amount to bind with all available free BTK to form quencher-bound BTK (QB-BTK) during blood sample collection. To measure a wide range of % BTK RO, including those of <5% or >95%, the required LLOQ at 0.125 nM for QB-BTK and 0.250 nM for drug-bound BTK (DB-BTK) in blood lysate were successfully achieved by using this IC-LC-MS/MS strategy. This proof-of-concept assay demonstrated its suitability with high throughput for real time in vivo BTK RO measurement as a pharmacodynamic (PD) biomarker for clinical drug development.


Assuntos
Tirosina Quinase da Agamaglobulinemia/metabolismo , Anticorpos Imobilizados/imunologia , Biomarcadores/metabolismo , Cromatografia Líquida/métodos , Inibidores de Proteínas Quinases/metabolismo , Receptores de Droga/metabolismo , Espectrometria de Massas em Tandem/métodos , Tirosina Quinase da Agamaglobulinemia/imunologia , Animais , Anticorpos Imobilizados/metabolismo , Bioensaio , Macaca fascicularis
20.
ACS Med Chem Lett ; 10(3): 383-388, 2019 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-30891145

RESUMO

In sharp contrast to a previously reported series of 6-anilino imidazopyridazine based Tyk2 JH2 ligands, 6-((2-oxo-N1-substituted-1,2-dihydropyridin-3-yl)amino)imidazo[1,2-b]pyridazine analogs were found to display dramatically improved metabolic stability. The N1-substituent on 2-oxo-1,2-dihydropyridine ring can be a variety of alkyl, aryl, and heteroaryl groups, but among them, 2-pyridyl provided much enhanced Caco-2 permeability, attributed to its ability to form intramolecular hydrogen bonds. Further structure-activity relationship studies at the C3 position led to the identification of highly potent and selective Tyk2 JH2 inhibitor 6, which proved to be highly effective in inhibiting IFNγ production in a rat pharmacodynamics model and fully efficacious in a rat adjuvant arthritis model.

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