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1.
N Engl J Med ; 387(5): 421-432, 2022 08 04.
Artículo en Inglés | MEDLINE | ID: mdl-35921451

RESUMEN

BACKGROUND: Aggregated α-synuclein plays an important role in the pathogenesis of Parkinson's disease. The monoclonal antibody prasinezumab, directed at aggregated α-synuclein, is being studied for its effect on Parkinson's disease. METHODS: In this phase 2 trial, we randomly assigned participants with early-stage Parkinson's disease in a 1:1:1 ratio to receive intravenous placebo or prasinezumab at a dose of 1500 mg or 4500 mg every 4 weeks for 52 weeks. The primary end point was the change from baseline to week 52 in the sum of scores on parts I, II, and III of the Movement Disorder Society-sponsored revision of the Unified Parkinson's Disease Rating Scale (MDS-UPDRS; range, 0 to 236, with higher scores indicating greater impairment). Secondary end points included the dopamine transporter levels in the putamen of the hemisphere ipsilateral to the clinically more affected side of the body, as measured by 123I-ioflupane single-photon-emission computed tomography (SPECT). RESULTS: A total of 316 participants were enrolled; 105 were assigned to receive placebo, 105 to receive 1500 mg of prasinezumab, and 106 to receive 4500 mg of prasinezumab. The baseline mean MDS-UPDRS scores were 32.0 in the placebo group, 31.5 in the 1500-mg group, and 30.8 in the 4500-mg group, and mean (±SE) changes from baseline to 52 weeks were 9.4±1.2 in the placebo group, 7.4±1.2 in the 1500-mg group (difference vs. placebo, -2.0; 80% confidence interval [CI], -4.2 to 0.2; P = 0.24), and 8.8±1.2 in the 4500-mg group (difference vs. placebo, -0.6; 80% CI, -2.8 to 1.6; P = 0.72). There was no substantial difference between the active-treatment groups and the placebo group in dopamine transporter levels on SPECT. The results for most clinical secondary end points were similar in the active-treatment groups and the placebo group. Serious adverse events occurred in 6.7% of the participants in the 1500-mg group and in 7.5% of those in the 4500-mg group; infusion reactions occurred in 19.0% and 34.0%, respectively. CONCLUSIONS: Prasinezumab therapy had no meaningful effect on global or imaging measures of Parkinson's disease progression as compared with placebo and was associated with infusion reactions. (Funded by F. Hoffmann-La Roche and Prothena Biosciences; PASADENA ClinicalTrials.gov number, NCT03100149.).


Asunto(s)
Anticuerpos Monoclonales Humanizados , Antiparkinsonianos , Enfermedad de Parkinson , alfa-Sinucleína , Anticuerpos Monoclonales Humanizados/uso terapéutico , Antiparkinsonianos/uso terapéutico , Proteínas de Transporte de Dopamina a través de la Membrana Plasmática/uso terapéutico , Método Doble Ciego , Humanos , Enfermedad de Parkinson/tratamiento farmacológico , Resultado del Tratamiento , alfa-Sinucleína/antagonistas & inhibidores
2.
Mov Disord ; 37(3): 585-597, 2022 03.
Artículo en Inglés | MEDLINE | ID: mdl-34897818

RESUMEN

BACKGROUND: Evaluating the discrepancies between patient-reported measures and clinician examination has implications for formulating individual treatment regimens. OBJECTIVE: This study investigated the association between health outcomes and level of self-reported motor-related function impairment relative to clinician-examined motor signs. METHODS: Recently diagnosed PD patients were evaluated using the Parkinson's Progression Marker Initiative (PPMI, N = 420) and the PASADENA phase II clinical trial (N = 316). We calculated the average normalized difference between each participant's part II and III MDS-UPDRS (Movement Disorder Society Unified Parkinson's Disease Rating Scale) scores. Individuals with score differences <25th or >75th percentiles were labeled as low- and high-self-reporters, respectively (those between ranges were labeled intermediate-self-reporters). We compared a wide range of clinical/biomarker readouts among these three groups, using Kruskal-Wallis nonparametric and Pearson's χ2 tests. Spearman's correlations were tested for associations between MDS-UPDRS subscales. RESULTS: In both cohorts, high-self-reporters reported the largest impairment/symptom experience for most motor and nonmotor patient-reported variables. By contrast, these high-self-reporters were similar to or less impaired on clinician-examined and biomarker measures. Patient-reported nonmotor symptoms on MDS-UPDRS part IB showed the strongest positive correlation with self-reported motor-related impairment (PPMI rs  = 0.54, PASADENA rs  = 0.52). This correlation was numerically stronger than the part II and clinician-examined MDS-UPDRS part III correlation (PPMI rs  = 0.38, PASADENA rs  = 0.28). CONCLUSION: Self-reported motor-related impairments reflect not only motor signs/symptoms but also other self-reported nonmotor measures. This may indicate (1) a direct impact of nonmotor symptoms on motor-related functioning and/or (2) the existence of general response tendencies in how patients self-rate symptoms. Our findings suggest further investigation into the suitability of MDS-UPDRS II to assess motor-related impairments. © 2021 The Authors. Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society.


Asunto(s)
Enfermedad de Parkinson , Humanos , Pruebas de Estado Mental y Demencia , Enfermedad de Parkinson/diagnóstico , Autoinforme , Índice de Severidad de la Enfermedad
3.
Mov Disord ; 36(8): 1972-1978, 2021 08.
Artículo en Inglés | MEDLINE | ID: mdl-33942926

RESUMEN

BACKGROUND: Cerebrospinal fluid (CSF) levels of monoamine metabolites may represent biomarkers of Parkinson's disease (PD). OBJECTIVE: The aim of this study was quantification of multiple metabolites in CSF from PD versus healthy control subjects (HCs), including longitudinal analysis. METHODS: Absolute levels of multiple monoamine metabolites in CSF were quantified by liquid chromatography coupled with tandem mass spectrometry from 161 individuals with early PD and 115 HCs from the Parkinson's Progression Marker Initiative and de novo PD (DeNoPA) studies. RESULTS: Baseline levels of homovanillic acid (HVA) and 3,4-dihydroxyphenylacetic acid (DOPAC) were lower in individuals with PD compared with HCs. HVA levels correlated with Movement Disorder Society Unified Parkinson's Disease Rating Scale total scores (P < 0.01). Both HVA/dopamine and DOPAC/dopamine levels correlated with caudate nucleus and raw DOPAC with putamen dopamine transporter single-photon emission computed tomography uptake ratios (P < 0.01). No metabolite changed over 2 years in drug-naive individuals, but some changed on starting levodopa treatment. CONCLUSIONS: HVA and DOPAC CSF levels mirrored nigrostriatal pathway damage, confirming the central role of dopaminergic degeneration in early PD. © 2021 The Authors. Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society.


Asunto(s)
Enfermedad de Parkinson , Ácido 3,4-Dihidroxifenilacético , Ácido Homovanílico , Humanos , Levodopa , Neurotransmisores , Enfermedad de Parkinson/diagnóstico por imagen , Enfermedad de Parkinson/tratamiento farmacológico
4.
Mov Disord ; 36(4): 895-904, 2021 04.
Artículo en Inglés | MEDLINE | ID: mdl-33232556

RESUMEN

BACKGROUND: Recent studies reported abnormal alpha-synuclein deposition in biopsy-accessible sites of the peripheral nervous system in Parkinson's disease (PD). This has considerable implications for clinical diagnosis. Moreover, if deposition occurs early, it may enable tissue diagnosis of prodromal PD. OBJECTIVE: The aim of this study was to develop and test an automated bright-field immunohistochemical assay of cutaneous pathological alpha-synuclein deposition in patients with idiopathic rapid eye movement sleep behavior disorder, PD, and atypical parkinsonism and in control subjects. METHODS: For assay development, postmortem skin biopsies were taken from 28 patients with autopsy-confirmed Lewy body disease and 23 control subjects. Biopsies were stained for pathological alpha-synuclein in automated stainers using a novel dual-immunohistochemical assay for serine 129-phosphorylated alpha-synuclein and pan-neuronal marker protein gene product 9.5. After validation, single 3-mm punch skin biopsies were taken from the cervical 8 paravertebral area from 79 subjects (28 idiopathic rapid eye movement sleep behavior disorder, 20 PD, 10 atypical parkinsonism, and 21 control subjects). Raters blinded to clinical diagnosis assessed the biopsies. RESULTS: The immunohistochemistry assay differentiated alpha-synuclein pathology from nonpathological-appearing alpha-synuclein using combined phosphatase and protease treatments. Among autopsy samples, 26 of 28 Lewy body samples and none of the 23 controls were positive. Among living subjects, punch biopsies were positive in 23 (82%) subjects with idiopathic rapid eye movement sleep behavior disorder, 14 (70%) subjects with PD, 2 (20%) subjects with atypical parkinsonism, and none (0%) of the control subjects. After a 3-year follow-up, eight idiopathic rapid eye movement sleep behavior disorder subjects phenoconverted to defined neurodegenerative syndromes, in accordance with baseline biopsy results. CONCLUSION: Even with a single 3-mm punch biopsy, there is considerable promise for using pathological alpha-synuclein deposition in skin to diagnose both clinical and prodromal PD. © 2020 International Parkinson and Movement Disorder Society.


Asunto(s)
Enfermedad por Cuerpos de Lewy , Enfermedad de Parkinson , Trastorno de la Conducta del Sueño REM , Humanos , Piel , alfa-Sinucleína
5.
Clin J Sport Med ; 31(1): 70-77, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-30300143

RESUMEN

OBJECTIVE: To examine rates of concussion and more severe concussion (time loss of greater than 10 days) in elite 13- to 17-year-old ice hockey players. METHODS: This is a prospective cohort study (Alberta, Canada). Bantam (13-14 years) and Midget (15-17 years) male and female elite (top 20% by division of play) youth ice hockey players participated in this study. Players completed a demographic and medical history questionnaire and clinical test battery at the beginning of the season. A previously validated injury surveillance system was used to document exposure hours and injury during one season of play (8 months). Players with a suspected ice hockey-related concussion were referred to the study sport medicine physicians for assessment. Time loss from hockey participation was documented on an injury report form. RESULTS: Overall, 778 elite youth ice hockey players (659 males and 119 females; aged 13-17 years) participated in this study. In total, 143 concussions were reported. The concussion incidence rate (IR) was 17.60 concussions/100 players (95% CI, 15.09-20.44). The concussion IR was 1.31 concussions/1000 player-hours (95% CI, 1.09-1.57). Time loss of greater than 10 days was reported in 74% of cases (106/143), and 20% (n = 28) had time loss of greater than 30 days. CONCLUSIONS: Concussion is a common injury in elite youth ice hockey players. In this study population, a large proportion of concussions (74%) resulted in a time loss of greater than 10 days, possibly reflecting more conservative management or longer recovery in youth athletes.


Asunto(s)
Traumatismos en Atletas/epidemiología , Conmoción Encefálica/epidemiología , Hockey/lesiones , Adolescente , Alberta/epidemiología , Femenino , Humanos , Incidencia , Masculino , Estudios Prospectivos , Deportes Juveniles/lesiones
6.
J Wound Care ; 30(5): 420-422, 2021 May 02.
Artículo en Inglés | MEDLINE | ID: mdl-33979223

RESUMEN

A cohort of patients presented to Queen Victoria Hospital, UK, with iatrogenic toe ischaemia following application of a different, newly available post-procedure dressing with different properties to those usually used. This resulted in ischaemia with extensive skin and soft tissue damage, requiring debridement surgery and, in some cases, skin grafting. We aim to highlight the risk of morbidity from dressing application to the digits. This is a key learning skill for anyone who may either perform dressings or evaluate dressings on digits in the community and across multiple specialties in hospital. This article follows a thorough root cause analysis and addresses other possible causes of an acutely painful erythematous toe post-Zadek's procedure.


Asunto(s)
Vendajes , Isquemia/etiología , Infección de la Herida Quirúrgica , Dedos del Pie/fisiopatología , Cicatrización de Heridas , Humanos , Piel , Trasplante de Piel
7.
Mov Disord ; 33(8): 1287-1297, 2018 08.
Artículo en Inglés | MEDLINE | ID: mdl-29701258

RESUMEN

BACKGROUND: Ubiquitous digital technologies such as smartphone sensors promise to fundamentally change biomedical research and treatment monitoring in neurological diseases such as PD, creating a new domain of digital biomarkers. OBJECTIVES: The present study assessed the feasibility, reliability, and validity of smartphone-based digital biomarkers of PD in a clinical trial setting. METHODS: During a 6-month, phase 1b clinical trial with 44 Parkinson participants, and an independent, 45-day study in 35 age-matched healthy controls, participants completed six daily motor active tests (sustained phonation, rest tremor, postural tremor, finger-tapping, balance, and gait), then carried the smartphone during the day (passive monitoring), enabling assessment of, for example, time spent walking and sit-to-stand transitions by gyroscopic and accelerometer data. RESULTS: Adherence was acceptable: Patients completed active testing on average 3.5 of 7 times/week. Sensor-based features showed moderate-to-excellent test-retest reliability (average intraclass correlation coefficient = 0.84). All active and passive features significantly differentiated PD from controls with P < 0.005. All active test features except sustained phonation were significantly related to corresponding International Parkinson and Movement Disorder Society-Sponsored UPRDS clinical severity ratings. On passive monitoring, time spent walking had a significant (P = 0.005) relationship with average postural instability and gait disturbance scores. Of note, for all smartphone active and passive features except postural tremor, the monitoring procedure detected abnormalities even in those Parkinson participants scored as having no signs in the corresponding International Parkinson and Movement Disorder Society-Sponsored UPRDS items at the site visit. CONCLUSIONS: These findings demonstrate the feasibility of smartphone-based digital biomarkers and indicate that smartphone-sensor technologies provide reliable, valid, clinically meaningful, and highly sensitive phenotypic data in Parkinson's disease. © 2018 The Authors. Movement Disorders published by Wiley Periodicals, Inc. on behalf of International Parkinson and Movement Disorder Society.


Asunto(s)
Antiparkinsonianos/uso terapéutico , Actividad Motora/fisiología , Evaluación de Resultado en la Atención de Salud/métodos , Enfermedad de Parkinson/diagnóstico , Enfermedad de Parkinson/fisiopatología , Teléfono Inteligente , Anciano , Estudios de Casos y Controles , Estudios de Factibilidad , Femenino , Humanos , Masculino , Persona de Mediana Edad , Examen Neurológico , Enfermedad de Parkinson/psicología , Cooperación del Paciente/psicología , Desempeño Psicomotor , Reproducibilidad de los Resultados , Índice de Severidad de la Enfermedad , Factores de Tiempo
8.
Neurobiol Learn Mem ; 141: 53-59, 2017 May.
Artículo en Inglés | MEDLINE | ID: mdl-28347876

RESUMEN

The parietal lobe is important for successful recognition memory, but its role is not yet fully understood. We investigated the parietal lobes' contribution to immediate paired-associate memory and delayed item-recognition memory separately for hits (targets) and correct rejections (distractors). We compared the behavioral performance of 56 patients with known parietal and medial temporal lobe dysfunction (i.e. early Alzheimer's Disease) to 56 healthy control participants in an immediate paired and delayed single item object memory task. Additionally, we performed voxel-based morphometry analyses to investigate the functional-neuroanatomic relationships between performance and voxel-based estimates of atrophy in whole-brain analyses. Behaviorally, all participants performed better identifying targets than rejecting distractors. The voxel-based morphometry analyses associated atrophy in the right ventral parietal cortex with fewer correct responses to familiar items (i.e. hits) in the immediate and delayed conditions. Additionally, medial temporal lobe integrity correlated with better performance in rejecting distractors, but not in identifying targets, in the immediate paired-associate task. Our findings suggest that the parietal lobe critically supports successful immediate and delayed target recognition memory, and that the ventral aspect of the parietal cortex and the medial temporal lobe may have complementary preferences for identifying targets and rejecting distractors, respectively, during recognition memory.


Asunto(s)
Amnesia/fisiopatología , Disfunción Cognitiva/fisiopatología , Lóbulo Parietal/fisiología , Reconocimiento en Psicología/fisiología , Anciano , Anciano de 80 o más Años , Amnesia/diagnóstico por imagen , Mapeo Encefálico , Disfunción Cognitiva/diagnóstico por imagen , Femenino , Humanos , Procesamiento de Imagen Asistido por Computador , Imagen por Resonancia Magnética , Masculino , Pruebas Neuropsicológicas , Lóbulo Parietal/diagnóstico por imagen
9.
Cereb Cortex ; 23(1): 187-97, 2013 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-22275484

RESUMEN

To recognize visual objects, our sensory perceptions are transformed through dynamic neural interactions into meaningful representations of the world but exactly how visual inputs invoke object meaning remains unclear. To address this issue, we apply a regression approach to magnetoencephalography data, modeling perceptual and conceptual variables. Key conceptual measures were derived from semantic feature-based models claiming shared features (e.g., has eyes) provide broad category information, while distinctive features (e.g., has a hump) are additionally required for more specific object identification. Our results show initial perceptual effects in visual cortex that are rapidly followed by semantic feature effects throughout ventral temporal cortex within the first 120 ms. Moreover, these early semantic effects reflect shared semantic feature information supporting coarse category-type distinctions. Post-200 ms, we observed the effects along the extent of ventral temporal cortex for both shared and distinctive features, which together allow for conceptual differentiation and object identification. By relating spatiotemporal neural activity to statistical feature-based measures of semantic knowledge, we demonstrate that qualitatively different kinds of perceptual and semantic information are extracted from visual objects over time, with rapid activation of shared object features followed by concomitant activation of distinctive features that together enable meaningful visual object recognition.


Asunto(s)
Envejecimiento/fisiología , Corteza Cerebral/fisiología , Reconocimiento Visual de Modelos/fisiología , Reconocimiento en Psicología/fisiología , Semántica , Adulto , Femenino , Humanos , Masculino
10.
Nat Med ; 30(4): 1096-1103, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38622249

RESUMEN

Prasinezumab, a monoclonal antibody that binds aggregated α-synuclein, is being investigated as a potential disease-modifying therapy in early-stage Parkinson's disease. Although in the PASADENA phase 2 study, the primary endpoint (Movement Disorder Society Unified Parkinson's Disease Rating Scale (MDS-UPDRS) sum of Parts I + II + III) was not met, prasinezumab-treated individuals exhibited slower progression of motor signs than placebo-treated participants (MDS-UPDRS Part III). We report here an exploratory analysis assessing whether prasinezumab showed greater benefits on motor signs progression in prespecified subgroups with faster motor progression. Prasinezumab's potential effects on disease progression were assessed in four prespecified and six exploratory subpopulations of PASADENA: use of monoamine oxidase B inhibitors at baseline (yes versus no); Hoehn and Yahr stage (2 versus 1); rapid eye movement sleep behavior disorder (yes versus no); data-driven subphenotypes (diffuse malignant versus nondiffuse malignant); age at baseline (≥60 years versus <60 years); sex (male versus female); disease duration (>12 months versus <12 months); age at diagnosis (≥60 years versus <60 years); motor subphenotypes (akinetic-rigid versus tremor-dominant); and motor subphenotypes (postural instability gait dysfunction versus tremor-dominant). In these subpopulations, the effect of prasinezumab on slowing motor signs progression (MDS-UPDRS Part III) was greater in the rapidly progressing subpopulations (for example, participants who were diffuse malignant or taking monoamine oxidase B inhibitors at baseline). This exploratory analysis suggests that, in a trial of 1-year duration, prasinezumab might reduce motor progression to a greater extent in individuals with more rapidly progressing Parkinson's disease. However, because this was a post hoc analysis, additional randomized clinical trials are needed to validate these findings.


Asunto(s)
Enfermedad de Parkinson , Humanos , Masculino , Femenino , Persona de Mediana Edad , Temblor/tratamiento farmacológico , Antiparkinsonianos/uso terapéutico , Monoaminooxidasa/uso terapéutico , Progresión de la Enfermedad
11.
J Cogn Neurosci ; 25(10): 1723-35, 2013 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-23662861

RESUMEN

Recognizing an object involves more than just visual analyses; its meaning must also be decoded. Extensive research has shown that processing the visual properties of objects relies on a hierarchically organized stream in ventral occipitotemporal cortex, with increasingly more complex visual features being coded from posterior to anterior sites culminating in the perirhinal cortex (PRC) in the anteromedial temporal lobe (aMTL). The neurobiological principles of the conceptual analysis of objects remain more controversial. Much research has focused on two neural regions-the fusiform gyrus and aMTL, both of which show semantic category differences, but of different types. fMRI studies show category differentiation in the fusiform gyrus, based on clusters of semantically similar objects, whereas category-specific deficits, specifically for living things, are associated with damage to the aMTL. These category-specific deficits for living things have been attributed to problems in differentiating between highly similar objects, a process that involves the PRC. To determine whether the PRC and the fusiform gyri contribute to different aspects of an object's meaning, with differentiation between confusable objects in the PRC and categorization based on object similarity in the fusiform, we carried out an fMRI study of object processing based on a feature-based model that characterizes the degree of semantic similarity and difference between objects and object categories. Participants saw 388 objects for which feature statistic information was available and named the objects at the basic level while undergoing fMRI scanning. After controlling for the effects of visual information, we found that feature statistics that capture similarity between objects formed category clusters in fusiform gyri, such that objects with many shared features (typical of living things) were associated with activity in the lateral fusiform gyri whereas objects with fewer shared features (typical of nonliving things) were associated with activity in the medial fusiform gyri. Significantly, a feature statistic reflecting differentiation between highly similar objects, enabling object-specific representations, was associated with bilateral PRC activity. These results confirm that the statistical characteristics of conceptual object features are coded in the ventral stream, supporting a conceptual feature-based hierarchy, and integrating disparate findings of category responses in fusiform gyri and category deficits in aMTL into a unifying neurocognitive framework.


Asunto(s)
Reconocimiento Visual de Modelos/fisiología , Reconocimiento en Psicología/fisiología , Corteza Visual/fisiología , Vías Visuales/fisiología , Adulto , Mapeo Encefálico , Femenino , Humanos , Procesamiento de Imagen Asistido por Computador , Imagen por Resonancia Magnética , Masculino , Nombres , Oxígeno/sangre , Tiempo de Reacción , Corteza Visual/irrigación sanguínea , Vías Visuales/irrigación sanguínea , Adulto Joven
12.
Hippocampus ; 23(9): 832-41, 2013 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-23609914

RESUMEN

Animal models agree that the perirhinal cortex plays a critical role in object recognition memory, but qualitative aspects of this mnemonic function are still debated. A recent model claims that the perirhinal cortex is required to recognize the novelty of confusable distractor stimuli, and that damage here results in an increased propensity to judge confusable novel objects as familiar (i.e., false positives). We tested this model in healthy participants and patients with varying degrees of perirhinal cortex damage, i.e., amnestic mild cognitive impairment and very early Alzheimer's disease (AD), with a recognition memory task with confusable and less confusable realistic object pictures, and from whom we acquired high-resolution anatomic MRI scans. Logistic mixed-model behavioral analyses revealed that both patient groups committed more false positives with confusable than less confusable distractors, whereas healthy participants performed comparably in both conditions. A voxel-based morphometry analysis demonstrated that this effect was associated with atrophy of the anteromedial temporal lobe, including the perirhinal cortex. These findings suggest that also the human perirhinal cortex recognizes the novelty of confusable objects, consistent with its border position between the hierarchical visual object processing and medial temporal lobe memory systems, and explains why AD patients exhibit a heightened propensity to commit false positive responses with inherently confusable stimuli.


Asunto(s)
Enfermedad de Alzheimer/complicaciones , Enfermedad de Alzheimer/patología , Disfunción Cognitiva/complicaciones , Disfunción Cognitiva/patología , Confusión/etiología , Lóbulo Temporal/patología , Anciano , Anciano de 80 o más Años , Atrofia/diagnóstico , Atrofia/patología , Confusión/patología , Femenino , Humanos , Modelos Logísticos , Masculino , Escala del Estado Mental , Persona de Mediana Edad
13.
Brain ; 135(Pt 12): 3757-69, 2012 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-23250887

RESUMEN

Our brain disambiguates the objects in our cluttered visual world seemingly effortlessly, enabling us to understand their significance and to act appropriately. The role of anteromedial temporal structures in this process, particularly the perirhinal cortex, is highly controversial. In some accounts, the perirhinal cortex is necessary for differentiating between perceptually and semantically confusable objects. Other models claim that the perirhinal cortex neither disambiguates perceptually confusable objects nor plays a unique role in semantic processing. One major hurdle to resolving this central debate is the fact that brain damage in human patients typically encompasses large portions of the anteromedial temporal lobe, such that the identification of individual substructures and precise neuroanatomical locus of the functional impairments has been difficult. We tested these competing accounts in patients with Alzheimer's disease with varying degrees of atrophy in anteromedial structures, including the perirhinal cortex. To assess the functional contribution of each anteromedial temporal region separately, we used a detailed region of interest approach. From each participant, we obtained magnetic resonance imaging scans and behavioural data from a picture naming task that contrasted naming performance with living and non-living things as a way of manipulating perceptual and semantic confusability; living things are more similar to one another than non-living things, which have more distinctive features. We manually traced neuroanatomical regions of interest on native-space cortical surface reconstructions to obtain mean thickness estimates for the lateral and medial perirhinal cortex and entorhinal cortex. Mean cortical thickness in each region of interest, and hippocampal volume, were submitted to regression analyses predicting naming performance. Importantly, atrophy of the medial perirhinal cortex, but not lateral perirhinal cortex, entorhinal cortex or hippocampus, significantly predicted naming performance on living relative to non-living things. These findings indicate that one specific anteromedial temporal lobe region-the medial perirhinal cortex-is necessary for the disambiguation of perceptually and semantically confusable objects. Taken together, these results support a hierarchical account of object processing, whereby the perirhinal cortex at the apex of the ventral object processing system is required to bind properties of not just perceptually, but also semantically confusable objects together, enabling their disambiguation from other similar objects and thus comprehension. Significantly, this model combining a hierarchical object processing architecture with a semantic feature statistic account explains why category-specific semantic impairments for living things are associated with anteromedial temporal lobe damage, and pinpoints the root of this syndrome to perirhinal cortex damage.


Asunto(s)
Enfermedad de Alzheimer/patología , Asociación , Mapeo Encefálico , Disfunción Cognitiva/patología , Corteza Entorrinal/patología , Reconocimiento Visual de Modelos/fisiología , Anciano , Anciano de 80 o más Años , Análisis de Varianza , Atrofia/patología , Comprensión , Femenino , Lateralidad Funcional , Humanos , Procesamiento de Imagen Asistido por Computador , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Pruebas Neuropsicológicas , Estimulación Luminosa , Tiempo de Reacción , Semántica
14.
Sci Rep ; 12(1): 12081, 2022 07 15.
Artículo en Inglés | MEDLINE | ID: mdl-35840753

RESUMEN

Digital health technologies enable remote and therefore frequent measurement of motor signs, potentially providing reliable and valid estimates of motor sign severity and progression in Parkinson's disease (PD). The Roche PD Mobile Application v2 was developed to measure bradykinesia, bradyphrenia and speech, tremor, gait and balance. It comprises 10 smartphone active tests (with ½ tests administered daily), as well as daily passive monitoring via a smartphone and smartwatch. It was studied in 316 early-stage PD participants who performed daily active tests at home then carried a smartphone and wore a smartwatch throughout the day for passive monitoring (study NCT03100149). Here, we report baseline data. Adherence was excellent (96.29%). All pre-specified sensor features exhibited good-to-excellent test-retest reliability (median intraclass correlation coefficient = 0.9), and correlated with corresponding Movement Disorder Society-Unified Parkinson's Disease Rating Scale items (rho: 0.12-0.71). These findings demonstrate the preliminary reliability and validity of remote at-home quantification of motor sign severity with the Roche PD Mobile Application v2 in individuals with early PD.


Asunto(s)
Aplicaciones Móviles , Enfermedad de Parkinson , Tecnología de Sensores Remotos , Humanos , Enfermedad de Parkinson/fisiopatología , Reproducibilidad de los Resultados , Teléfono Inteligente , Temblor/fisiopatología
15.
J Cogn Neurosci ; 23(8): 1887-99, 2011 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-20617883

RESUMEN

Research on the spatio-temporal dynamics of visual object recognition suggests a recurrent, interactive model whereby an initial feedforward sweep through the ventral stream to prefrontal cortex is followed by recurrent interactions. However, critical questions remain regarding the factors that mediate the degree of recurrent interactions necessary for meaningful object recognition. The novel prediction we test here is that recurrent interactivity is driven by increasing semantic integration demands as defined by the complexity of semantic information required by the task and driven by the stimuli. To test this prediction, we recorded magnetoencephalography data while participants named living and nonliving objects during two naming tasks. We found that the spatio-temporal dynamics of neural activity were modulated by the level of semantic integration required. Specifically, source reconstructed time courses and phase synchronization measures showed increased recurrent interactions as a function of semantic integration demands. These findings demonstrate that the cortical dynamics of object processing are modulated by the complexity of semantic information required from the visual input.


Asunto(s)
Mapeo Encefálico , Lóbulo Occipital/fisiología , Reconocimiento Visual de Modelos/fisiología , Reconocimiento en Psicología/fisiología , Semántica , Lóbulo Temporal/fisiología , Adulto , Ondas Encefálicas , Femenino , Humanos , Imagenología Tridimensional , Magnetoencefalografía , Masculino , Nombres , Vías Nerviosas/fisiología , Dinámicas no Lineales , Estimulación Luminosa/métodos , Tiempo de Reacción/fisiología , Adulto Joven
16.
Front Neurosci ; 15: 765765, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34966256

RESUMEN

Currently, no treatments available for Parkinson's disease (PD) can slow PD progression. At the early stage of the disease, only a subset of individuals with PD progress quickly, while the majority have a slowly progressive form of the disease. In developing treatments that aim to slow PD progression, clinical trials aim to include individuals who are likely to progress faster, such that a treatment effect, if one exists, can be identified easier and earlier. The aim of the present study was to identify baseline predictors of clinical progression in early PD. We analyzed 12-month data acquired from the PASADENA trial Part 1 (NCT03100149, n = 76 participants who were allocated to the placebo arm and did not start symptomatic therapy) and the Parkinson's Progression Markers Initiative (PPMI) study (n = 139 demographically and clinically matched participants). By using ridge regression models including clinical characteristics, imaging, and non-imaging biomarkers, we found that Hoehn and Yahr stage and dopamine transporter single-photon emission computed tomography specific binding ratios (Dat-SPECT SBR) in putamen ipsilateral to the side of motor symptom onset predicted PD progression at the early stage of the disease. Further studies are needed to confirm the validity of these predictors to identify with high accuracy individuals with early PD with a faster progression phenotype.

17.
Plast Reconstr Surg Glob Open ; 9(6): e3612, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-34104616

RESUMEN

The aim of this study was to examine for the presence of implicit bias within the field of plastic surgery using a gender-specific Implicit Association Test (IAT), specifically looking at gender and career stereotypes. METHODS: A Gender-Career/Family Implicit Association Test was developed and distributed to the international plastic surgery community. Mean scores were calculated. Respondents were provided with an automated summary interpretation of their results, categorizing association for a particular grouping of gender and career/family as a little or no, slight, moderate, or strong. Respondents were also asked a series of demographic and post-IAT questions. RESULTS: Ninety-five responses were available for analysis. Overall, respondents showed a moderate-to-strong association of male + career / female + family compared with the reverse, which was statistically significant. Nearly half of the respondents thought they might have an implicit gender-related bias; however, 50% post-test would not change their behavior based on results, while 9.5% would. CONCLUSIONS: Plastics surgeons may have an unconscious tendency to associate men with a career and women with a family. Further steps must be taken to increase awareness and mitigate the impact of implicit gender bias.

18.
BMJ Open ; 11(2): e045162, 2021 02 11.
Artículo en Inglés | MEDLINE | ID: mdl-33574155

RESUMEN

INTRODUCTION: Human amniotic fluid (hAF) has been shown to reduce inflammation in multiple experimental models. hAF has previously been approved by the US Food and Drug Administration (FDA) as a human cellular and tissue product for tissue injury for human administration, and used safely in thousands of patients as a therapeutic treatment for diverse conditions. Given the profound inflammatory response observed in patients with COVID-19, and the successful completion of 10-patient pilot study of intravenous hAF, we present a trial design for a larger clinical trial of intravenous hAF for the treatment of COVID-19. METHODS AND ANALYSIS: This paper describes the methodology of a phase I/II randomised, double-blinded, placebo-controlled clinical trial to determine the safety and feasibility of using acellular sterile filtered amniotic fluid as a treatment for patients with COVID-19. Primary outcome will be the change in C-reactive protein. Secondary outcomes include safety, biomarker inflammatory levels and clinically relevant outcomes at 30 days, including mortality, ventilator-free days and hospital and intensive care unit length of stay. Exploratory outcomes of health-related quality-of-life patient-reported outcomes will be collected. Hospitalised patients with laboratory-confirmed COVID-19 will be recruited. ETHICS AND DISSEMINATION: This study was approved by the University of Utah Institutional Review Board (IRB_0013292), approved by the US FDA under Investigational New Drug (No 23369) and is registered on ClinicalTrials.gov. Results will be disseminated via peer-reviewed publications and conference presentations. TRIAL REGISTRATION NUMBER: NCT04497389; Pre-results.


Asunto(s)
Líquido Amniótico , Productos Biológicos/uso terapéutico , COVID-19/terapia , Proteína C-Reactiva/análisis , Método Doble Ciego , Estudios de Factibilidad , Humanos , Inflamación/terapia , Proyectos Piloto , Ensayos Clínicos Controlados Aleatorios como Asunto , Resultado del Tratamiento
19.
J Assoc Nurses AIDS Care ; 32(6): 640-651, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33273157

RESUMEN

ABSTRACT: People living with HIV (PLWH) are at increased risk for cardiovascular disease. Physical activity, exercise, and controlled diet can mitigate this risk, yet these behaviors are understudied in sub-Saharan Africa. Our objective was to describe and compare the meaning, value, and patterns of physical activity, exercise, and diet among PLWH and older adults without HIV in Uganda. This mixed methods, observational study included 30 adult PLWH and 29 adults without HIV who (a) wore an accelerometer to measure physical activity; (b) had weight, height, and waist and hip circumference measured; (c) completed physical fitness measures; and (d) used digital cameras to record photographs and videos of their typical diet and physical activities. Participants were approximately 58 years old and 68% female. Approximately 20% of PLWH and 40% of adults without HIV met physical activity guidelines (p > .05). Qualitative themes included engaging in a variety of exercise, structural barriers to exercising, and typical meals. Older adults in Uganda have low levels of physical activity and homogenous diets, increasing their risk for cardiovascular disease.


Asunto(s)
Enfermedades Cardiovasculares , Infecciones por VIH , Anciano , Dieta , Ejercicio Físico , Femenino , Humanos , Masculino , Persona de Mediana Edad , Uganda
20.
Arch Clin Neuropsychol ; 36(5): 838-843, 2021 Jul 19.
Artículo en Inglés | MEDLINE | ID: mdl-33237317

RESUMEN

OBJECTIVE: Reduced semantic memory performance is a known neuropsychological marker of very early Alzheimer's disease (AD), but the task format that best predicts disease status is an open question. The present study aimed to identify the semantic fluency task and measure that best discriminates early-stage AD patients (PATs) from cognitively healthy controls. METHOD: Semantic fluency performance for animals, fruits, tools, and vehicles was assessed in 70 early-stage AD PATs and 67 cognitively healthy participants. Logistic regressions and receiver operating characteristics were calculated for five total score semantic fluency measures. RESULTS: Compared with all other measures, living things (i.e., total correct animals + total correct fruits) achieved highest z-statistics, highest area under the curve and smallest difference between the upper and lower 95% confidence intervals. CONCLUSION: Living things total correct is a powerful tool to detect the earliest signs of incipient AD.


Asunto(s)
Enfermedad de Alzheimer , Semántica , Enfermedad de Alzheimer/diagnóstico , Humanos , Pruebas Neuropsicológicas , Conducta Verbal
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