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1.
Opt Lett ; 49(7): 1794-1797, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38560865

RESUMO

In this work, we design and experimentally demonstrate the first, to the best of our knowledge, integrated polarization splitters and rotators at blue wavelengths. We develop compact and efficient designs for both a polarization splitter and rotator at a 422-nm wavelength, an important laser-cooling transition for 88Sr+ ions. These devices are fabricated in a 200-mm wafer-scale process and experimentally demonstrated, resulting in a measured polarization-splitter transverse-electric thru-port coupling of 98.0% and transverse-magnetic tap-port coupling of 77.6% for a compact 16-µm-long device and a polarization-rotator conversion efficiency of 92.2% for a separate compact 111-µm-long device. This work paves the way for more sophisticated integrated control of trapped-ion and neutral-atom quantum systems.

2.
Alzheimers Dement ; 20(3): 1771-1783, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38109286

RESUMO

INTRODUCTION: Associations of cerebellar atrophy with specific neuropathologies in Alzheimer's disease and related dementias (ADRD) have not been systematically analyzed. This study examined cerebellar gray matter volume across major pathological subtypes of ADRD. METHODS: Cerebellar gray matter volume was examined using voxel-based morphometry in 309 autopsy-proven ADRD cases and 80 healthy controls. ADRD subtypes included AD, mixed Lewy body disease and AD (LBD-AD), and frontotemporal lobar degeneration (FTLD). Clinical function was assessed using the Clinical Dementia Rating (CDR) scale. RESULTS: Distinct patterns of cerebellar atrophy were observed in all ADRD subtypes. Significant cerebellar gray matter changes appeared in the early stages of most subtypes and the very early stages of AD, LBD-AD, FTLD-TDP type A, and progressive supranuclear palsy. Cortical atrophy positively predicted cerebellar atrophy across all subtypes. DISCUSSION: Our findings establish pathology-specific profiles of cerebellar atrophy in ADRD and propose cerebellar neuroimaging as a non-invasive biomarker for differential diagnosis and disease monitoring. HIGHLIGHTS: Cerebellar atrophy was examined in 309 patients with autopsy-proven neurodegeneration. Distinct patterns of cerebellar atrophy are found in all pathological subtypes of Alzheimer's disease and related dementias (ADRD). Cerebellar atrophy is seen in early-stage (Clinical Dementia Rating [CDR] ≤1) AD, Lewy body dementia (LBD), frontotemporal lobar degeneration with tau-positive inclusion (FTLD-tau), and FTLD-transactive response DNA binding protein (FTLD-TDP). Cortical atrophy positively predicts cerebellar atrophy across all neuropathologies.


Assuntos
Doença de Alzheimer , Demência Frontotemporal , Degeneração Lobar Frontotemporal , Doença por Corpos de Lewy , Doenças Neurodegenerativas , Humanos , Doença de Alzheimer/patologia , Degeneração Lobar Frontotemporal/genética , Doença por Corpos de Lewy/diagnóstico , Atrofia , Proteínas tau/metabolismo
6.
Front Neurol ; 14: 1197213, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37492849

RESUMO

Introduction: Persons with behavioral variant frontotemporal dementia (bvFTD) can exhibit apparently antisocial behaviors. An example is their tendency to adopt utilitarian choices in sacrificial moral dilemmas, i.e. harmful actions to promote overall welfare. Moral cognition models interpret such tendencies as deriving from a lack of emotional engagement and selective impairment in prosocial sentiments. Methods: We applied a qualitative approach to test those theoretical assumptions and to further explore the emotional experiences and values of people with bvFTD while they contemplate moral scenarios. We conducted semistructured interviews with 14 participants: 7 persons with bvFTD and 7 older healthy controls. Transcripts were coded using ATLAS.ti 5.0. Results: During the moral reasoning task, persons with bvFTD reported more positive emotions than negative and showed significantly less cognitive precision in their moral reasoning compared to controls. Persons with bvFTD also organized their choices predominantly around kindness and altruism, and their responses reflected higher rule compliance. Our study showed that bvFTD persons' utilitarian responses to moral dilemmas did not arise from an emotionally disengaged or antisocial perspective. Instead, they were underpinned by positive emotionality and prosocial values. Discussion: These findings enrich current understandings of moral cognition and highlight the importance of incorporating mixed methods approaches in dementia research that take into consideration the viewpoint of cognitively impaired individuals.

7.
Cereb Cortex ; 33(12): 7627-7641, 2023 06 08.
Artigo em Inglês | MEDLINE | ID: mdl-36939283

RESUMO

The etiology of Alzheimer's dementia has been hypothesized in terms of basal forebrain cholinergic decline, and in terms of reflecting beta-amyloid neuropathology. To study these different biological elements, we activated the basal forebrain in 5xFAD Alzheimer's model mice and littermates. Mice received 5 months of 1 h per day intermittent stimulation of the basal forebrain, which includes cholinergic projections to the cortical mantle. Then, mice were behaviorally tested followed by tissue analysis. The 5xFAD mice performed worse in water-maze testing than littermates. Stimulated groups learned the water maze better than unstimulated groups. Stimulated groups had 2-3-fold increases in frontal cortex immunoblot measures of the neurotrophin receptors for nerve growth factor and brain-derived neurotrophic factor, and a more than 50% decrease in the expression of amyloid cleavage enzyme BACE1. Stimulation also led to lower Aß42 in 5xFAD mice. These data support a causal relationship between basal forebrain activation and both neurotrophin activation and reduced Aß42 generation and accumulation. The observation that basal forebrain activation suppresses Aß42 accumulation, combined with the known high-affinity antagonism of nicotinic receptors by Aß42, documents bidirectional antagonism between acetylcholine and Aß42.


Assuntos
Doença de Alzheimer , Prosencéfalo Basal , Camundongos , Animais , Doença de Alzheimer/patologia , Receptores de Fator de Crescimento Neural , Camundongos Transgênicos , Memória Espacial , Secretases da Proteína Precursora do Amiloide/metabolismo , Ácido Aspártico Endopeptidases/metabolismo , Peptídeos beta-Amiloides/metabolismo , Colinérgicos
8.
Alzheimers Dement ; 19(7): 2842-2852, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-36591730

RESUMO

INTRODUCTION: Empathy relies on fronto-cingular and temporal networks that are selectively vulnerable in behavioral variant frontotemporal dementia (bvFTD). This study modeled when in the disease process empathy changes begin, and how they progress. METHODS: Four hundred thirty-one individuals with asymptomatic genetic FTD (n = 114), genetic and sporadic bvFTD (n = 317), and 163 asymptomatic non-carrier controls were enrolled. In sub-samples, we investigated empathy measured by the informant-based Interpersonal Reactivity Index (IRI) at each disease stage and over time (n = 91), and its correspondence to underlying atrophy (n = 51). RESULTS: Empathic concern (estimate = 4.38, 95% confidence interval [CI] = 2.79, 5.97; p < 0.001) and perspective taking (estimate = 5.64, 95% CI = 3.81, 7.48; p < 0.001) scores declined between the asymptomatic and very mild symptomatic stages regardless of pathogenic variant status. More rapid loss of empathy corresponded with subcortical atrophy. DISCUSSION: Loss of empathy is an early and progressive symptom of bvFTD that is measurable by IRI informant ratings and can be used to monitor behavior in neuropsychiatry practice and treatment trials.


Assuntos
Empatia , Demência Frontotemporal , Humanos , Demência Frontotemporal/diagnóstico , Testes Neuropsicológicos , Atrofia , Imageamento por Ressonância Magnética
9.
Dela J Public Health ; 9(4): 6-10, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-38173959

RESUMO

This paper proposes a quadrilateral approach to advance biopharmaceutical manufacturing by fostering collaboration among biopharma, lab informatics, healthcare systems, and academia. Through a retrospection based on Gary Pisano's analysis and real-world examples like insitro and Spark Therapeutics, we highlight the imperative of continuous process innovation and regulatory collaboration. We emphasize leveraging technological advancements, particularly in machine learning and artificial intelligence (AI), to catalyze a paradigm shift in drug manufacturing and delivery. The discussion extends to fostering academic and business partnerships, akin to Silicon Valley's ecosystem, and engaging healthcare systems in a more integrated role, exemplified by the advent of point-of-care manufacturing. The paper underscores the unique potential of the State of Delaware to propel forward the biopharma manufacturing space, advocating for a coordinated effort to translate scientific advancements into real healthcare benefits.

10.
Brain ; 145(11): 4080-4096, 2022 11 21.
Artigo em Inglês | MEDLINE | ID: mdl-35731122

RESUMO

Focal anterior temporal lobe degeneration often preferentially affects the left or right hemisphere. While patients with left-predominant anterior temporal lobe atrophy show severe anomia and verbal semantic deficits and meet criteria for semantic variant primary progressive aphasia and semantic dementia, patients with early right anterior temporal lobe atrophy are more difficult to diagnose as their symptoms are less well understood. Focal right anterior temporal lobe atrophy is associated with prominent emotional and behavioural changes, and patients often meet, or go on to meet, criteria for behavioural variant frontotemporal dementia. Uncertainty around early symptoms and absence of an overarching clinico-anatomical framework continue to hinder proper diagnosis and care of patients with right anterior temporal lobe disease. Here, we examine a large, well-characterized, longitudinal cohort of patients with right anterior temporal lobe-predominant degeneration and propose new criteria and nosology. We identified individuals from our database with a clinical diagnosis of behavioural variant frontotemporal dementia or semantic variant primary progressive aphasia and a structural MRI (n = 478). On the basis of neuroimaging criteria, we defined three patient groups: right anterior temporal lobe-predominant atrophy with relative sparing of the frontal lobes (n = 46), frontal-predominant atrophy with relative sparing of the right anterior temporal lobe (n = 79) and left-predominant anterior temporal lobe-predominant atrophy with relative sparing of the frontal lobes (n = 75). We compared the clinical, neuropsychological, genetic and pathological profiles of these groups. In the right anterior temporal lobe-predominant group, the earliest symptoms were loss of empathy (27%), person-specific semantic impairment (23%) and complex compulsions and rigid thought process (18%). On testing, this group exhibited greater impairments in Emotional Theory of Mind, recognition of famous people (from names and faces) and facial affect naming (despite preserved face perception) than the frontal- and left-predominant anterior temporal lobe-predominant groups. The clinical symptoms in the first 3 years of the disease alone were highly sensitive (81%) and specific (84%) differentiating right anterior temporal lobe-predominant from frontal-predominant groups. Frontotemporal lobar degeneration-transactive response DNA binding protein (84%) was the most common pathology of the right anterior temporal lobe-predominant group. Right anterior temporal lobe-predominant degeneration is characterized by early loss of empathy and person-specific knowledge, deficits that are caused by progressive decline in semantic memory for concepts of socioemotional relevance. Guided by our results, we outline new diagnostic criteria and propose the name, 'semantic behavioural variant frontotemporal dementia', which highlights the underlying cognitive mechanism and the predominant symptomatology. These diagnostic criteria will facilitate early identification and care of patients with early, focal right anterior temporal lobe degeneration as well as in vivo prediction of frontotemporal lobar degeneration-transactive response DNA binding protein pathology.


Assuntos
Afasia Primária Progressiva , Demência Frontotemporal , Degeneração Lobar Frontotemporal , Humanos , Demência Frontotemporal/patologia , Semântica , Degeneração Lobar Frontotemporal/diagnóstico por imagem , Degeneração Lobar Frontotemporal/patologia , Atrofia , Imageamento por Ressonância Magnética , Afasia Primária Progressiva/diagnóstico por imagem , Afasia Primária Progressiva/patologia , Proteínas de Ligação a DNA , Testes Neuropsicológicos
11.
Brain Res ; 1789: 147947, 2022 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-35597325

RESUMO

In this study a manganese-enhanced magnetic resonance imaging (MEMRI) method was developed for mice for measuring axonal transport (AXT) rates in real time in olfactory receptor neurons, which project from the olfactory epithelium to the olfactory neuronal layer of the olfactory bulb. Using this MEMRI method, two major experiments were conducted: 1) an evaluation of the effects of age on AXT rates and 2) an evaluation of the brain-penetrant, microtubule-stabilizing agent, Epothilone D for effect on AXT rates in aged mice. In these studies, we improved upon previous MEMRI approaches to develop a method where real-time measurements (32 time points) of AXT rates in mice can be determined over a single (approximately 100 min) scanning session. In the age comparisons, AXT rates were significantly higher in young (mean age ∼4.0 months old) versus aged (mean age ∼24.5 months old) mice. Moreover, in aged mice, eight weeks of treatment with Epothilone D, (0.3 and 1.0 mg/kg) was associated with statistically significant increases in AXT rates compared to vehicle-treated subjects. These experiments conducted in a living mammalian model (i.e., wild type, C57BL/6 mice), using a new modified MEMRI method, thus provide further evidence that the process of aging leads to decreases in AXT rates in the brain and they further support the argument that microtubule-based therapeutic strategies designed to improve AXT rates have potential for age-related neurological disorders.


Assuntos
Transporte Axonal , Manganês , Animais , Humanos , Imageamento por Ressonância Magnética/métodos , Mamíferos , Manganês/farmacologia , Camundongos , Camundongos Endogâmicos C57BL , Microtúbulos
12.
Orphanet J Rare Dis ; 17(1): 38, 2022 02 05.
Artigo em Inglês | MEDLINE | ID: mdl-35123544

RESUMO

INTRODUCTION: Individuals with proopiomelanocortin (POMC) or leptin receptor (LEPR) deficiency are young and experience severe obesity, hyperphagia, and comorbidities, which can impair quality of life (QOL). METHODS: Two pivotal Phase 3 trials explored the effect of setmelanotide on body weight and hunger in individuals with obesity due to POMC (NCT02896192) or LEPR (NCT03287960) deficiency. QOL and depression were investigated in parallel using the disease-specific, age-appropriate Impact of Weight on Quality of Life-Lite (IWQOL-Lite), Pediatric Quality of Life Inventory (PedsQL), and Patient Health Questionnaire-9 (PHQ-9). RESULTS: In total, the POMC and LEPR trials enrolled 21 patients. Adults (≥ 18 years old; n = 7) had moderate-to-severe impairment in QOL at baseline, with mean (standard deviation [SD]) IWQOL-Lite total score 60.3 (13.2; maximum IWQOL-Lite total score = 100). The effect of setmelanotide on IWQOL-Lite total score was observed as soon as Week 5. Among those with scores at Week 52, 5 of 6 adults experienced a clinically meaningful improvement, with mean (SD) total scores increased from baseline by 24.2 (12.1) points. Children (6-12 years old; n = 2) and adolescents (13-17 years old; n = 4) had impaired QOL at baseline, with mean (SD) self-reported PedsQL total scores 53.3 (6.2) and 63.3 (29.1), respectively (maximum PedsQL total score = 100). Three of 5 patients experienced clinically meaningful improvement in PedsQL, with 2 children whose PedsQL total score increased by 28.3 and 3.3 points and 3 adolescents whose mean (SD) total score increased from baseline by 5.8 (18.3) points. Baseline mean (SD) PHQ-9 score (in those ≥ 12 years old) was 5.3 (3.8) and was generally maintained through Week 52. CONCLUSIONS: Patients with POMC or LEPR deficiency had impaired, and in some cases severely impaired, QOL before setmelanotide treatment. Setmelanotide improved QOL in patients as early as Week 5, with some patients no longer experiencing impaired QOL at Week 52. Improvements in QOL may be related to a reduction in hunger and body weight associated with setmelanotide. Because of the highly complex psychological consequences of rare genetic diseases of obesity, some patients may require a long period of treatment to improve QOL and benefit from interdisciplinary care.


Assuntos
Pró-Opiomelanocortina , Qualidade de Vida , Adolescente , Adulto , Criança , Humanos , Obesidade/tratamento farmacológico , Receptores para Leptina , Inquéritos e Questionários , alfa-MSH/análogos & derivados
13.
Front Psychol ; 13: 1062452, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36605275

RESUMO

Dementia caregiving, besides encompassing various challenges in tandem to the diagnosis of the care recipient, is associated with decreased psychological well-being and mental health. Accordingly, caregivers' wellbeing has an impact on the quality of care they provide and on the relationship quality with the person in their care. The aim of the present study is to examine the effectiveness of a mindfulness-based intervention on relational and psychological wellbeing, tailored to the needs of dementia caregivers. This clinical trial (NCT04977245) will apply a randomized controlled mixed method design. Caregivers will be randomly allocated to either the mindfulness intervention or the active control group. The intervention arm is based on experiential learning and is targeted to promote caregivers' well-being and empowerment. Assessments will include, standardized self-report questionnaires, task performance measures, and qualitative measures. All assessments will be held at three time points (baseline; t0, 0 months, post-intervention; t1, 2 months, and after maintenance; t2, 3 months) focused on three core domains (1. relational well-being, 2. psychological well-being, and 3. dementia patient's lifestyle/activities). The primary outcome will be relational well-being, and data will be analyzed using linear mixed modelling.

14.
Cell Mol Life Sci ; 78(21-22): 6941-6961, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34580742

RESUMO

Gulf War Illness (GWI), a disorder suffered by approximately 200,000 veterans of the first Gulf War, was caused by exposure to low-level organophosphate pesticides and nerve agents in combination with battlefield stress. To elucidate the mechanistic basis of the brain-related symptoms of GWI, human-induced pluripotent stem cells (hiPSCs) derived from veterans with or without GWI were differentiated into forebrain glutamatergic neurons and then exposed to a Gulf War (GW) relevant toxicant regimen consisting of a sarin analog and cortisol, a human stress hormone. Elevated levels of total and phosphorylated tau, reduced microtubule acetylation, altered mitochondrial dynamics/transport, and decreased neuronal activity were observed in neurons exposed to the toxicant regimen. Some of the data are consistent with the possibility that some veterans may have been predisposed to acquire GWI. Wistar rats exposed to a similar toxicant regimen showed a mild learning and memory deficit, as well as cell loss and tau pathology selectively in the CA3 region of the hippocampus. These cellular responses offer a mechanistic explanation for the memory loss suffered by veterans with GWI and provide a cell-based model for screening drugs and developing personalized therapies for these veterans.


Assuntos
Síndrome do Golfo Pérsico/patologia , Animais , Região CA3 Hipocampal/patologia , Diferenciação Celular/fisiologia , Células Cultivadas , Modelos Animais de Doenças , Guerra do Golfo , Humanos , Células-Tronco Pluripotentes Induzidas/patologia , Masculino , Transtornos da Memória/patologia , Neurônios/patologia , Ratos , Ratos Wistar , Veteranos
15.
Front Neurol ; 12: 683162, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34557141

RESUMO

Neurodegenerative disease syndromes often affect personality and interpersonal behavior in addition to cognition, but there are few structured observational measures of altered social demeanor validated for this population. We developed the Social Behavior Observer Checklist (SBOCL), a 3-min checklist tool, to facilitate identification of patterns of interpersonal behavior that are diagnostically relevant to different neurodegenerative syndromes. Research assistants without formal clinical training in dementia used the SBOCL to describe participants' behavior, including 125 healthy older adults and 357 patients diagnosed with one of five neurodegenerative disease syndromes: 135 behavioral variant frontotemporal dementia (bvFTD), 57 semantic variant primary progressive aphasia (svPPA), 51 non-fluent variant PPA (nfvPPA), 65 progressive supranuclear palsy (PSP), and 49 amyloid-positive Alzheimer's disease syndrome (AD), all of whom had concurrent 3D T1 MRI scans available for voxel-based morphometry analysis. SBOCL item interrater reliability ranged from moderate to very high, and score elevations showed syndrome-specific patterns. Subscale scores derived from a degree*frequency product of the items had excellent positive predictive value for identifying patients. Specifically, scores above 2 on the Disorganized subscale, and above 3 on the Reactive and Insensitive subscales, were not seen in any healthy controls but were found in many patients with bvFTD, svPPA, nfvPPA, PSP, and AD syndromes. Both the Disorganized and Reactive subscale scores showed significant linear relationships with frontal and temporal gray matter volume that generalized across syndromes. With these initial psychometric characteristics, the SBOCL may be a useful measure to help non-experts identify patients who are appropriate for additional specialized dementia evaluation, without adding time to patient encounters or requiring the presence of an informant.

16.
Alzheimers Dement (Amst) ; 13(1): e12183, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34268446

RESUMO

INTRODUCTION: Behavioral variant frontotemporal dementia (bvFTD) can be computationally divided into four distinct anatomic subtypes based on patterns of frontotemporal and subcortical atrophy. To more precisely predict disease trajectories of individual patients, the temporal stability of each subtype must be characterized. METHODS: We investigated the longitudinal stability of the four previously identified anatomic subtypes in 72 bvFTD patients. We also applied a voxel-wise mixed effects model to examine subtype differences in atrophy patterns across multiple timepoints. RESULTS: Our results demonstrate the stability of the anatomic subtypes at baseline and over time. While they had common salience network atrophy, each subtype showed distinctive baseline and longitudinal atrophy patterns. DISCUSSION: Recognizing these anatomically heterogeneous subtypes and their different patterns of atrophy progression in early bvFTD will improve disease course prediction in individual patients. Longitudinal volumetric predictions based on these anatomic subtypes may be used as a more accurate endpoint in treatment trials.

17.
J Am Soc Echocardiogr ; 34(12): 1253-1261.e4, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34284098

RESUMO

BACKGROUND: The authors retrospectively evaluated the impact of ultrasound enhancing agent (UEA) use in the first transthoracic echocardiographic (TTE) examination, regardless of baseline image quality, on the number of repeat TTEs and length of stay (LOS) during a heart failure (HF) admission. METHODS: There were 9,115 HF admissions associated with admission TTE examinations over a 4-year period (5,337 men; mean age, 67.6 ± 15.0 years). Patients were grouped into those who received UEAs (contrast group) in the first TTE study and those who did not (noncontrast group). Repeat TTE examinations were classified as justified if performed for concrete clinical indications during hospitalization. RESULTS: In the 9,115 admissions for HF (5,600 in the contrast group, 3,515 in the noncontrast group), 927 patients underwent repeat TTE studies (505 in the contrast group, 422 in the noncontrast group), which were considered justified in 823 patients. Of the 104 patients who underwent unjustified repeat TTE studies, 80 (76.7%) belonged to the noncontrast group and 24 to the contrast group. Also, UEA use increased from 50.4% in 2014 to 74.3%, and the rate of unjustified repeat studies decreased from 1.3% to 0.9%. The rates of unjustified repeat TTE imaging were 2.3% and 0.4% (in the noncontrast and contrast groups, respectively), and patients in the contrast group were less likely to undergo unjustified repeat examinations (odds ratio, 0.18; 95% CI, 0.12-0.29; P < .0001). The mean LOS was significantly lower in the contrast group (9.5 ± 10.5 vs 11.1 ± 13.7 days). The use of UEA in the first TTE study was also associated with reduced LOS (linear regression, ß1 = -0.47, P = .036), with 20% lower odds for odds of prolonged (>6 days) LOS. CONCLUSIONS: The routine use of UEA in the first TTE examination for HF irrespective of image quality is associated with reduced unjustified repeat TTE testing and may reduce LOS during an index HF admission.


Assuntos
Ecocardiografia , Insuficiência Cardíaca , Idoso , Idoso de 80 Anos ou mais , Insuficiência Cardíaca/diagnóstico por imagem , Insuficiência Cardíaca/epidemiologia , Hospitalização , Humanos , Pessoa de Meia-Idade , Estudos Retrospectivos , Ultrassonografia
18.
Sci Rep ; 11(1): 9843, 2021 05 10.
Artigo em Inglês | MEDLINE | ID: mdl-33972592

RESUMO

Nicotinic acetylcholine receptors (nAChRs) play a critical role in the neuropharmacology of learning and memory. As such, naturally occurring alkaloids that regulate nAChR activity have gained interest for understanding and potentially improving memory function. In this study, we tested the acute effects of three known nicotinic alkaloids, nicotine, cotinine, and anatabine, in suppressing scopolamine-induced memory deficit in rodents by using two classic memory paradigms, Y-maze and novel object recognition (NOR) in mice and rats, respectively. We found that all compounds were able to suppress scopolamine-induced spatial memory deficit in the Y-maze spontaneous alternation paradigm. However, only nicotine was able to suppress the short-term object memory deficit in NOR, despite the higher doses of cotinine and anatabine used to account for their potential differences in nAChR activity. These results indicate that cotinine and anatabine can uniquely regulate short-term spatial memory, while nicotine seems to have more robust and general role in memory regulation in rodents. Thus, nAChR-activating alkaloids may possess distinct procognitive properties in rodents, depending on the memory types examined.


Assuntos
Transtornos da Memória/tratamento farmacológico , Memória de Curto Prazo/efeitos dos fármacos , Agonistas Nicotínicos/administração & dosagem , Receptores Nicotínicos/metabolismo , Memória Espacial/efeitos dos fármacos , Alcaloides/administração & dosagem , Animais , Cotinina/administração & dosagem , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Humanos , Masculino , Aprendizagem em Labirinto/efeitos dos fármacos , Transtornos da Memória/induzido quimicamente , Camundongos , Nicotina/administração & dosagem , Piridinas/administração & dosagem , Ratos , Escopolamina/toxicidade
19.
Neuropharmacology ; 187: 108489, 2021 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-33561449

RESUMO

Rodent models have facilitated major discoveries in neurobiology, however, the low success rate of novel medications in clinical trials have led to questions about their translational value in neuropsychiatric drug development research. For age-related disorders of cognition such as Alzheimer' disease (AD) there is interest in moving beyond transgenic amyloid-ß and/or tau-expressing rodent models and focusing more on natural aging and dissociating "healthy" from "pathological" aging to identify new therapeutic targets and treatments. In complex disorders such as AD, it can also be argued that animals with closer neurobiology to humans (e.g., nonhuman primates) should be employed more often particularly in the later phases of drug development. The purpose of the work described here was to evaluate the cognitive capabilities of rhesus monkeys across a wide range of ages in different delayed response tasks, a computerized delayed match to sample (DMTS) task and a manual delayed match to position (DMTP) task. Based on specific performance criteria and comparisons to younger subjects, the older subjects were generally less proficient, however, some performed as well as young subjects, while other aged subjects were markedly impaired. Accordingly, the older subjects could be categorized as aged "cognitively-unimpaired" or aged "cognitively-impaired" with a third group (aged-other) falling in between. Finally, as a proof of principle, we demonstrated using the DMTP task that aged cognitively-impaired monkeys are sensitive to the pro-cognitive effects of a nicotinic acetylcholine receptor (nAChR) partial agonist, encenicline, suggesting that nAChR ligands remain viable as potential treatments for age-related disorders of cognition.


Assuntos
Envelhecimento/psicologia , Cognição/fisiologia , Disfunção Cognitiva/fisiopatologia , Memória de Curto Prazo/fisiologia , Animais , Cognição/efeitos dos fármacos , Avaliação Pré-Clínica de Medicamentos , Feminino , Macaca mulatta , Masculino , Memória de Curto Prazo/efeitos dos fármacos , Nootrópicos/farmacologia , Quinuclidinas/farmacologia , Tiofenos/farmacologia
20.
ACS Appl Mater Interfaces ; 13(1): 836-847, 2021 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-33216550

RESUMO

We have directly written nanoscale patterns of magnetic ordering in FeRh films using focused helium-ion beam irradiation. By varying the dose, we pattern arrays with metamagnetic transition temperatures that range from the as-grown film temperature to below room temperature. We employ transmission electron microscopy, X-ray diffraction, and temperature-dependent transport measurements to characterize the as-grown film, and magneto-optic Kerr effect imaging to quantify the He+ irradiation-induced changes to the magnetic order. Moreover, we demonstrate temperature-dependent optical microscopy and conductive atomic force microscopy as indirect probes of the metamagnetic transition that are sensitive to the differences in dielectric properties and electrical conductivity, respectively, of FeRh in the antiferromagnetic (AF) and ferromagnetic (FM) states. Using density functional theory, we quantify strain- and defect-induced changes in spin-flip energy to understand their influence on the metamagnetic transition temperature. This work holds promise for in-plane AF-FM spintronic devices, by reducing the need for multiple patterning steps or different materials, and potentially eliminating interfacial polarization losses due to cross material interfacial spin scattering.

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