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1.
Neuroimage ; 273: 120067, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-36997134

RESUMEN

Both the primate visual system and artificial deep neural network (DNN) models show an extraordinary ability to simultaneously classify facial expression and identity. However, the neural computations underlying the two systems are unclear. Here, we developed a multi-task DNN model that optimally classified both monkey facial expressions and identities. By comparing the fMRI neural representations of the macaque visual cortex with the best-performing DNN model, we found that both systems: (1) share initial stages for processing low-level face features which segregate into separate branches at later stages for processing facial expression and identity respectively, and (2) gain more specificity for the processing of either facial expression or identity as one progresses along each branch towards higher stages. Correspondence analysis between the DNN and monkey visual areas revealed that the amygdala and anterior fundus face patch (AF) matched well with later layers of the DNN's facial expression branch, while the anterior medial face patch (AM) matched well with later layers of the DNN's facial identity branch. Our results highlight the anatomical and functional similarities between macaque visual system and DNN model, suggesting a common mechanism between the two systems.


Asunto(s)
Expresión Facial , Macaca , Animales , Redes Neurales de la Computación , Primates , Imagen por Resonancia Magnética/métodos , Reconocimiento Visual de Modelos
3.
J Neuroophthalmol ; 38(2): 202-209, 2018 06.
Artículo en Inglés | MEDLINE | ID: mdl-29750734

RESUMEN

: BACKGROUND:: The visual pathways are increasingly recognized as an ideal model to study neurodegeneration in multiple sclerosis (MS). Low-contrast letter acuity (LCLA) and optical coherence tomography (OCT) are validated measures of function and structure in MS. In fact, LCLA was the topic of a recent review by the Multiple Sclerosis Outcome Assessments Consortium (MSOAC) to qualify this visual measure as a primary or secondary clinical trial endpoint with the Food and Drug Administration (FDA) and other regulatory agencies. This review focuses on the use of LCLA and OCT measures as outcomes in clinical trials to date of MS disease-modifying therapies. METHODS: A Pubmed search using the specific key words "optical coherence tomography," "low-contrast letter acuity," "multiple sclerosis," and "clinical trials" was performed. An additional search on the clinicaltrials.gov website with the same key words was used to find registered clinical trials of MS therapies that included these visual outcome measures. RESULTS: As demonstrated by multiple clinical trials, LCLA and OCT measures are sensitive to treatment effects in MS. LCLA has been used in many clinical trials to date, and findings suggest that 7 letters of LCLA at the 2.5% contrast level are meaningful change. Few clinical trials using the benefits of OCT have been performed, although results of observational studies have solidified the ability of OCT to assess change in retinal structure. Continued accrual of clinical trial and observational data is needed to validate the use of OCT in clinical trials, but preliminary work suggests that an intereye difference in retinal nerve fiber layer thickness of 5-6 µm is a clinically meaningful threshold that identifies an optic nerve lesion in MS. CONCLUSIONS: Visual impairment represents a significant component of overall disability in MS. LCLA and OCT enhance the detection of visual pathway injury and can be used as measures of axonal and neuronal integrity. Continued investigation is ongoing to further incorporate these vision-based assessments into clinical trials of MS therapies.


Asunto(s)
Ensayos Clínicos como Asunto , Esclerosis Múltiple/fisiopatología , Trastornos de la Visión/fisiopatología , Agudeza Visual/fisiología , Humanos , Esclerosis Múltiple/tratamiento farmacológico , Fibras Nerviosas/patología , Neuritis Óptica/tratamiento farmacológico , Neuritis Óptica/fisiopatología , Evaluación de Resultado en la Atención de Salud , Células Ganglionares de la Retina/patología , Perfil de Impacto de Enfermedad , Tomografía de Coherencia Óptica , Trastornos de la Visión/tratamiento farmacológico
4.
J Neuroophthalmol ; 38(4): 494-501, 2018 12.
Artículo en Inglés | MEDLINE | ID: mdl-30418332

RESUMEN

BACKGROUND: The International Multiple Sclerosis Visual System Consortium (IMSVISUAL) was formed in November 2014 with the primary goal of improving research, care, and education regarding the role of the visual system in multiple sclerosis (MS) and related disorders. METHODS: In this review, we describe the formation, goals, activities, and structure of IMSVISUAL, as well as the relationship of IMSVISUAL with the Americas Committee for Treatment and Research in MS (ACTRIMS). Finally, we provide an overview of the work IMSVISUAL has completed to date, as well as an outline of research projects ongoing under the auspices of IMSVISUAL. RESULTS: IMSVISUAL has 140 members worldwide and continues to grow. Through IMSVISUAL-related research, optical coherence tomography (OCT)-derived peripapillary retinal nerve fiber layer (pRNFL) thinning has been established as a predictor of future disability in MS. IMSVISUAL has also developed guidelines for reporting OCT studies in MS. Moreover, a systematic review performed by IMSVISUAL found that not only are pRNFL and ganglion cell + inner plexiform layer (GCIPL) thicknesses reduced in patients with MS (particularly in eyes with prior optic neuritis [ON]), but that inner nuclear layer measures may be higher among MS ON eyes, relative to healthy control eyes. Currently, there are several ongoing IMSVISUAL projects that will establish a role for visual outcomes in diagnosing MS and quantifying the effects of emerging therapies in clinical trials. CONCLUSIONS: The development of IMSVISUAL represents a major collaborative commitment to defining the role of visual outcomes in high-quality, large-scale studies that generate definitive and instructive findings in the field of MS. As a consortium, IMSVISUAL has completed several international collaborative projects, is actively engaged in numerous ongoing research studies, and is committed to expanding the role of vision research in MS and related disorders.


Asunto(s)
Investigación Biomédica/normas , Manejo de la Enfermedad , Oftalmopatías , Esclerosis Múltiple/terapia , Oftalmología , Guías de Práctica Clínica como Asunto , Agudeza Visual , Oftalmopatías/diagnóstico , Oftalmopatías/etiología , Oftalmopatías/terapia , Humanos , Esclerosis Múltiple/complicaciones , Esclerosis Múltiple/diagnóstico
5.
J Neuroophthalmol ; 38(4): 451-458, 2018 12.
Artículo en Inglés | MEDLINE | ID: mdl-29384802

RESUMEN

BACKGROUND: The optic nerve is a frequent site for involvement in multiple sclerosis (MS). Optical coherence tomography (OCT) detects thinning of the retinal nerve fiber layer (RNFL) in eyes of patients with MS and in those meeting criteria for clinically or radiologically isolated demyelinating syndromes. Current international diagnostic criteria for MS do not include the optic nerve as an imaging lesion site despite the high prevalence of acute optic neuritis (ON), or occult optic neuropathy, among early MS and clinically isolated syndrome patients; as well as most MS patients over the course of the disease. We sought to determine optimal thresholds for intereye difference in peripapillary RNFL thickness that are most predictive of a unilateral optic nerve lesion. METHODS: We analyzed spectral domain OCT data of 31 healthy volunteers and 124 patients with MS at a single center as part of an ongoing collaborative investigation of visual outcomes. Intereye differences in peripapillary (360°) RNFL thickness were calculated as the absolute value of the difference. First, we determined the 95th percentile value of intereye difference for the healthy volunteers. This value was applied to the convenience sample group of MS patients as a validation cohort determining how well this threshold could distinguish patients with vs without a history of unilateral ON. The relation of intereye differences in peripapillary RNFL thickness to binocular low-contrast letter acuity scores was also examined. RESULTS: Among healthy volunteer participants (n = 31), the 95th percentile value for intereye difference (upper boundary of expected for normal controls) was 6.0 µm. This value was applied to the convenience sample group of MS patients (n = 124, validation cohort). Positive predictive value, negative predictive value, sensitivity, and specificity for identifying MS patients with a history of unilateral ON were calculated for the 6-µm threshold value in a 2 × 2 table analysis with the application of χ tests (P < 0.0001). The 6-µm threshold was predictive of worse binocular low-contrast acuity scores at 2.5% (P = 0.03) and 1.25% (P = 0.002 by linear regression analyses). A receiver operating characteristic curve analysis demonstrated an optimal intereye difference threshold of 5 µm for identifying unilateral ON in the MS cohort. CONCLUSIONS: An intereye difference of 5-6 µm in RNFL thickness is a robust structural threshold for identifying the presence of a unilateral optic nerve lesion in MS.


Asunto(s)
Esclerosis Múltiple/complicaciones , Nervio Óptico/patología , Neuritis Óptica/diagnóstico , Células Ganglionares de la Retina/patología , Tomografía de Coherencia Óptica/métodos , Agudeza Visual , Adulto , Femenino , Humanos , Masculino , Esclerosis Múltiple/diagnóstico , Fibras Nerviosas/patología , Neuritis Óptica/etiología , Pronóstico
6.
J Neuroophthalmol ; 38(1): 24-29, 2018 03.
Artículo en Inglés | MEDLINE | ID: mdl-28746058

RESUMEN

BACKGROUND: The King-Devick (K-D) test of rapid number naming is a reliable visual performance measure that is a sensitive sideline indicator of concussion when time scores worsen (lengthen) from preseason baseline. Within cohorts of youth athletes <18 years old, baseline K-D times become faster with increasing age. We determined the relation of rapid number-naming time scores on the K-D test to electronic measurements of saccade performance during preseason baseline assessments in a collegiate ice hockey team cohort. Within this group of young adult athletes, we also sought to examine the potential role for player age in determining baseline scores. METHODS: Athletes from a collegiate ice hockey team received preseason baseline testing as part of an ongoing study of rapid rink-side performance measures for concussion. These included the K-D test (spiral-bound cards and tablet computer versions). Participants also performed a laboratory-based version of the K-D test with simultaneous infrared-based video-oculographic recordings using an EyeLink 1000+. This allowed measurement of the temporal and spatial characteristics of eye movements, including saccadic velocity, duration, and intersaccadic interval (ISI). RESULTS: Among 13 male athletes, aged 18-23 years (mean 20.5 ± 1.6 years), prolongation of the ISI (a combined measure of saccade latency and fixation duration) was the measure most associated with slower baseline time scores for the EyeLink-paired K-D (mean 38.2 ± 6.2 seconds, r = 0.88 [95% CI 0.63-0.96], P = 0.0001), the K-D spiral-bound cards (36.6 ± 5.9 seconds, r = 0.60 [95% CI 0.08-0.87], P = 0.03), and K-D computerized tablet version (39.1 ± 5.4 seconds, r = 0.79 [95% CI 0.42-0.93], P = 0.001). In this cohort, older age was a predictor of longer (worse) K-D baseline time performance (age vs EyeLink-paired K-D: r = 0.70 [95% CI 0.24-0.90], P = 0.008; age vs K-D spiral-bound cards: r = 0.57 [95% CI 0.03-0.85], P = 0.04; age vs K-D tablet version: r = 0.59 [95% CI 0.06-0.86], P = 0.03) as well as prolonged ISI (r = 0.62 [95% CI 0.11-0.87], P = 0.02). Slower baseline K-D times were not associated with greater numbers of reported prior concussions. CONCLUSIONS: Rapid number-naming performance using the K-D at preseason baseline in this small cohort of collegiate ice hockey players is best correlated with ISI among eye movement-recording measures. Baseline K-D scores notably worsened with increasing age, but not with numbers of prior concussions in this small cohort. While these findings require further investigation by larger studies of contact and noncontact sports athletes, they suggest that duration of contact sports exposure may influence preseason test performance.


Asunto(s)
Traumatismos en Atletas/diagnóstico , Conmoción Encefálica/diagnóstico , Hockey/lesiones , Pruebas Neuropsicológicas , Movimientos Sacádicos/fisiología , Pruebas de Visión/métodos , Adolescente , Traumatismos en Atletas/fisiopatología , Conmoción Encefálica/fisiopatología , Humanos , Masculino , Universidades , Adulto Joven
7.
Mult Scler ; 23(5): 734-747, 2017 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-28206829

RESUMEN

Low-contrast letter acuity (LCLA) has emerged as the leading outcome measure to assess visual disability in multiple sclerosis (MS) research. As visual dysfunction is one of the most common manifestations of MS, sensitive visual outcome measures are important in examining the effect of treatment. Low-contrast acuity captures visual loss not seen in high-contrast visual acuity (HCVA) measurements. These issues are addressed by the MS Outcome Assessments Consortium (MSOAC), including representatives from advocacy organizations, Food and Drug Administration (FDA), European Medicines Agency (EMA), National Institute of Neurological Disorders and Stroke (NINDS), academic institutions, and industry partners along with persons living with MS. MSOAC goals are acceptance and qualification by regulators of performance outcomes that are highly reliable and valid, practical, cost-effective, and meaningful to persons with MS. A critical step is elucidation of clinically relevant benchmarks, well-defined degrees of disability, and gradients of change that are clinically meaningful. This review shows that MS and disease-free controls have similar median HCVA, while MS patients have significantly lower LCLA. Deficits in LCLA and vision-specific quality of life are found many years after an episode of acute optic neuritis, even when HCVA has recovered. Studies reveal correlations between LCLA and the Expanded Disability Status Score (EDSS), Multiple Sclerosis Functional Composite (MSFC), retinal nerve fiber layer (RNFL) and ganglion cell layer plus inner plexiform layer (GCL + IPL) thickness on optical coherence tomography (OCT), brain magnetic resonance imaging (MRI), visual evoked potential (VEP), electroretinogram (ERG), pupillary function, and King-Devick testing. This review also concludes that a 7-point change in LCLA is clinically meaningful. The overall goal of this review is to describe and characterize the LCLA metric for research and clinical use among persons with MS.


Asunto(s)
Potenciales Evocados Visuales/fisiología , Esclerosis Múltiple/diagnóstico , Examen Neurológico , Evaluación de Resultado en la Atención de Salud , Agudeza Visual/fisiología , Humanos , Esclerosis Múltiple/patología , Examen Neurológico/métodos , Evaluación de Resultado en la Atención de Salud/métodos , Calidad de Vida
8.
Neuroimage ; 130: 77-90, 2016 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-26826513

RESUMEN

Recognition of facial expressions is crucial for effective social interactions. Yet, the extent to which the various face-selective regions in the human brain classify different facial expressions remains unclear. We used functional magnetic resonance imaging (fMRI) and support vector machine pattern classification analysis to determine how well face-selective brain regions are able to decode different categories of facial expression. Subjects participated in a slow event-related fMRI experiment in which they were shown 32 face pictures, portraying four different expressions: neutral, fearful, angry, and happy and belonging to eight different identities. Our results showed that only the amygdala and the posterior superior temporal sulcus (STS) were able to accurately discriminate between these expressions, albeit in different ways: the amygdala discriminated fearful faces from non-fearful faces, whereas STS discriminated neutral from emotional (fearful, angry and happy) faces. In contrast to these findings on the classification of emotional expression, only the fusiform face area (FFA) and anterior inferior temporal cortex (aIT) could discriminate among the various facial identities. Further, the amygdala and STS were better than FFA and aIT at classifying expression, while FFA and aIT were better than the amygdala and STS at classifying identity. Taken together, our findings indicate that the decoding of facial emotion and facial identity occurs in different neural substrates: the amygdala and STS for the former and FFA and aIT for the latter.


Asunto(s)
Encéfalo/fisiología , Discriminación en Psicología/fisiología , Reconocimiento Visual de Modelos/fisiología , Adulto , Mapeo Encefálico , Emociones/fisiología , Expresión Facial , Femenino , Humanos , Procesamiento de Imagen Asistido por Computador , Imagen por Resonancia Magnética , Masculino , Máquina de Vectores de Soporte
9.
J Neuroophthalmol ; 36(4): 369-376, 2016 12.
Artículo en Inglés | MEDLINE | ID: mdl-27472185

RESUMEN

BACKGROUND: Although patients with acute optic neuritis (ON) recover high-contrast visual acuity (HCVA) to 20/40 or better in 95% of affected eyes, patients with a history of ON continue to note subjective abnormalities of vision. Furthermore, substantial and permanent thinning of the retinal nerve fiber layer (RNFL) and the ganglion cell layer (GCL) is now known to occur early in the course of ON. We measured vision-specific quality of life (QOL) in patients with a history of acute ON and recovery of VA to 20/40 or better in their affected eyes to determine how these QOL scores relate to RNFL and GCL thickness and low-contrast letter acuity (LCLA) across the spectrum of visual recovery. METHODS: Data from an ongoing collaborative study of visual outcomes in multiple sclerosis and ON were analyzed for this cross-sectional observational cohort. Patients and disease-free control participants completed the 25-Item National Eye Institute Visual Functioning Questionnaire (NEI-VFQ-25) and 10-Item Neuro-Ophthalmic Supplement to the NEI-VFQ-25, as well as VA and LCLA testing for each eye separately and binocularly. Optical coherence tomography measures for each eye included peripapillary RNFL thickness and macular GCL + inner plexiform layer (GCL + IPL) thickness. RESULTS: Patients with a history of acute ON and recovery to 20/40 or better VA (n = 113) had significantly reduced scores for the NEI-VFQ-25 (83.7 ± 15.4) and 10-Item Neuro-Ophthalmic Supplement (74.6 ± 17.4) compared with disease-free controls (98.2 ± 2.1 and 96.4 ± 5.2, P < 0.001, linear regression models, accounting for age and within-patient, intereye correlations). Most patients with 20/40 or better visual recovery (98/112, 88%) had monocular HCVA in their affected eye of 20/20 or better. Although patients with 20/50 or worse HCVA recovery demonstrated the worst performance on low-contrast acuity, affected eye RNFL and GCL + IPL thickness, and QOL scales, these measures were also significantly reduced among those with 20/40 or better HCVA recovery compared with controls. CONCLUSIONS: Patients with a history of ON and "good" visual recovery, defined in the literature as 20/40 or better HCVA, are left with clinically meaningful reductions in vision-specific QOL. Such patient-observed deficits reflect the underlying significant degrees of retinal axonal and neuronal loss and visual dysfunction that are now known to characterize ON even in the setting of maximal HCVA recovery. There remains an unmet therapeutic need for patients with ON.


Asunto(s)
Fibras Nerviosas/patología , Neuritis Óptica/fisiopatología , Recuperación de la Función , Células Ganglionares de la Retina/patología , Tomografía de Coherencia Óptica/métodos , Agudeza Visual , Enfermedad Aguda , Adulto , Estudios Transversales , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Neuritis Óptica/diagnóstico , Factores de Tiempo
10.
Semin Neurol ; 35(5): 564-77, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-26444402

RESUMEN

Optical coherence tomography (OCT) is a relatively new technology that is now routinely and very widely used by ophthalmologists for structural documentation of the optic nerve and retina. In neuro-ophthalmology and neurology, the value of OCT is ever expanding; its role in an increasing number of conditions is being reported in parallel with the advances of the technology. Currently, as a clinical tool, OCT is particularly useful for the structural measurement of peripapillary retinal nerve fiber layer thickness, optic nerve head volumetric analysis, and macular anatomy. Optic neuropathies of varied etiology (particularly from multiple sclerosis) may be the most common clinical indications for neurologists to obtain OCT imaging. Documentation and follow-up of disc edema of varied etiology (papilledema and idiopathic intracranial hypertension), discriminating true disc swelling from pseudopapilledema, and differentiating optic neuropathy from maculopathy are some other examples from clinical practice.


Asunto(s)
Enfermedades del Sistema Nervioso/diagnóstico , Neurología/métodos , Oftalmología/métodos , Tomografía de Coherencia Óptica/métodos , Humanos
11.
bioRxiv ; 2024 Jun 10.
Artículo en Inglés | MEDLINE | ID: mdl-38915663

RESUMEN

The catecholamine neurotransmitter dopamine is classically known for regulation of central nervous system (CNS) functions such as reward, movement, and cognition. Increasing evidence also indicates that dopamine regulates critical functions in peripheral organs and is an important immunoregulatory factor. We have previously shown that dopamine increases NF-κB activity, inflammasome activation, and the production of inflammatory cytokines such as IL-1ß in human macrophages. As myeloid lineage cells are central to the initiation and resolution of acute inflammatory responses, dopamine-mediated dysregulation of these functions could both impair the innate immune response and exacerbate chronic inflammation. However, the exact pathways by which dopamine drives myeloid inflammation are not well defined, and studies in both rodent and human systems indicate that dopamine can impact the production of inflammatory mediators through both D1-like dopamine receptors (DRD1, DRD5) and D2-like dopamine receptors (DRD2, DRD3, and DRD4). Therefore, we hypothesized that dopamine-mediated production of IL-1ß in myeloid cells is regulated by the ratio of different dopamine receptors that are activated. Our data in primary human monocyte-derived macrophages (hMDM) indicate that DRD1 expression is necessary for dopamine-mediated increases in IL-1ß, and that changes in the expression of DRD2 and other dopamine receptors can alter the magnitude of the dopamine-mediated increase in IL-1ß. Mature hMDM have a high D1-like to D2-like receptor ratio, which is different relative to monocytes and peripheral blood mononuclear cells (PBMCs). We further confirm in human microglia cell lines that a high ratio of D1-like to D2-like receptors promotes dopamine-induced increases in IL-1ß gene and protein expression using pharmacological inhibition or overexpression of dopamine receptors. RNA-sequencing of dopamine-treated microglia shows that genes encoding functions in IL-1ß signaling pathways, microglia activation, and neurotransmission increased with dopamine treatment. Finally, using HIV as an example of a chronic inflammatory disease that is substantively worsened by comorbid substance use disorders (SUDs) that impact dopaminergic signaling, we show increased effects of dopamine on inflammasome activation and IL-1ß in the presence of HIV in both human macrophages and microglia. These data suggest that use of addictive substances and dopamine-modulating therapeutics could dysregulate the innate inflammatory response and exacerbate chronic neuroimmunological conditions like HIV. Thus, a detailed understanding of dopamine-mediated changes in inflammation, in particular pathways regulating IL-1ß, will be critical to effectively tailor medication regimens.

12.
Bipolar Disord ; 15(4): 365-76, 2013 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-23621705

RESUMEN

OBJECTIVES: A broad range of subtle and markedly heterogenous neuroanatomical abnormalities of grey matter and white matter have been reported in bipolar disorder. Euthymic bipolar disorder patients represent a clinically homogenous group in which to identify trait-based biomarkers of bipolar disorder. In this study, we sought to clarify the nature and extent of neuroanatomical differences in a large, clinically homogeneous group of euthymic bipolar disorder patients. METHODS: Structural magnetic resonance imaging (sMRI) was obtained for 60 patients with prospectively confirmed euthymic bipolar I disorder and 60 individually age- and gender-matched healthy volunteers. High angular resolution diffusion tensor imaging (DTI) scans were obtained for a subset of this sample comprising 35 patients and 43 controls. Voxel-based analysis of both sMRI and DTI data sets was performed. RESULTS: Bipolar disorder patients displayed global reductions in white matter volume and fractional anisotropy reductions in the corpus callosum, posterior cingulum, and prefrontal white matter compared with controls. There were corresponding increases in radial diffusivity in the callosal splenium in patients compared with controls. No significant group differences were detected in grey matter. In patients, lithium was associated with a bilateral increase in grey matter volume in the temporal lobes, but not with any DTI parameter. CONCLUSIONS: Euthymic bipolar I disorder is characterized by both diffuse global white matter deficits and potential regional disorganization in interhemispheric and longitudinal tracts, while grey matter appears to be preserved.


Asunto(s)
Trastorno Bipolar , Compuestos de Litio/farmacología , Adulto , Afecto/clasificación , Afecto/fisiología , Antimaníacos/farmacología , Trastorno Bipolar/tratamiento farmacológico , Trastorno Bipolar/patología , Trastorno Bipolar/psicología , Imagen de Difusión por Resonancia Magnética/métodos , Imagen de Difusión Tensora/métodos , Sustancia Gris/efectos de los fármacos , Sustancia Gris/patología , Humanos , Masculino , Persona de Mediana Edad , Tamaño de los Órganos/efectos de los fármacos , Evaluación de Resultado en la Atención de Salud , Escalas de Valoración Psiquiátrica , Sustancia Blanca/patología
13.
Brain ; 135(Pt 6): 1786-93, 2012 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-22539259

RESUMEN

Macular oedema typically results from blood-retinal barrier disruption. It has recently been reported that patients with multiple sclerosis treated with FTY-720 (fingolimod) may exhibit macular oedema. Multiple sclerosis is not otherwise thought to be associated with macular oedema except in the context of comorbid clinical uveitis. Despite a lack of myelin, the retina is a site of inflammation and microglial activation in multiple sclerosis and demonstrates significant neuronal and axonal loss. We unexpectedly observed microcystic macular oedema using spectral domain optical coherence tomography in patients with multiple sclerosis who did not have another reason for macular oedema. We therefore evaluated spectral domain optical coherence tomography images in consecutive patients with multiple sclerosis for microcystic macular oedema and examined correlations between macular oedema and visual and ambulatory disability in a cross-sectional analysis. Participants were excluded if there was a comorbidity that could account for the presence of macular oedema, such as uveitis, diabetes or other retinal disease. A microcystic pattern of macular oedema was observed on optical coherence tomography in 15 of 318 (4.7%) patients with multiple sclerosis. No macular oedema was identified in 52 healthy controls assessed over the same period. The microcystic oedema predominantly involved the inner nuclear layer of the retina and tended to occur in small, discrete patches. Patients with multiple sclerosis with microcystic macular oedema had significantly worse disability [median Expanded Disability Score Scale 4 (interquartile range 3-6)] than patients without macular oedema [median Expanded Disability Score Scale 2 (interquartile range 1.5-3.5)], P = 0.0002. Patients with multiple sclerosis with microcystic macular oedema also had higher Multiple Sclerosis Severity Scores, a measure of disease progression, than those without oedema [median of 6.47 (interquartile range 4.96-7.98) versus 3.65 (interquartile range 1.92-5.87), P = 0.0009]. Microcystic macular oedema occurred more commonly in eyes with prior optic neuritis than eyes without prior optic neuritis (50 versus 27%) and was associated with lower visual acuity (median logMAR acuity of 0.17 versus -0.1) and a thinner retinal nerve fibre layer. The presence of microcystic macular oedema in multiple sclerosis suggests that there may be breakdown of the blood-retinal barrier and tight junction integrity in a part of the nervous system that lacks myelin. Microcystic macular oedema may also contribute to visual dysfunction beyond that explained by nerve fibre layer loss. Microcystic changes need to be assessed, and potentially adjusted for, in clinical trials that evaluate macular volume as a marker of retinal ganglion cell survival. These findings also have implications for clinical monitoring in patients with multiple sclerosis on sphingosine 1-phosphate receptor modulating agents.


Asunto(s)
Edema Macular/complicaciones , Edema Macular/diagnóstico , Esclerosis Múltiple/complicaciones , Adulto , Distribución de Chi-Cuadrado , Estudios Transversales , Evaluación de la Discapacidad , Femenino , Estudios de Seguimiento , Humanos , Edema Macular/epidemiología , Masculino , Persona de Mediana Edad , Esclerosis Múltiple/diagnóstico , Esclerosis Múltiple/epidemiología , Índice de Severidad de la Enfermedad , Tomografía de Coherencia Óptica , Agudeza Visual
14.
Food Chem Toxicol ; 174: 113685, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-36813153

RESUMEN

Parkinson's Disease (PD) and Alcohol Use Disorder (AUD) are disorders that involve similar dopaminergic neurobiological pathways and dysregulations in motivation- and reward-related behaviors. This study explored whether exposure to a PD-related neurotoxicant, paraquat (PQ), alters binge-like alcohol drinking and striatal monoamines in mice selectively bred for high alcohol preference (HAP), and whether these effects are sex-dependent. Previous studies found female mice are less susceptible to PD-related toxicants compared to male mice. Mice were treated with PQ or vehicle over 3 weeks (10 mg/kg, i.p. once per week) and binge-like alcohol [20% (v/v)] drinking was assessed. Mice were euthanized and brains were microdissected for monoamine analyses by high performance liquid chromatography with electrochemical detection (HPLC-ECD). PQ-treated HAP male mice showed significantly decreased binge-like alcohol drinking and ventral striatal 3,4-Dihydroxyphenylacetic acid (DOPAC) levels compared to vehicle-treated HAP mice. These effects were absent in female HAP mice. These findings suggest that male HAP mice may be more susceptible than female mice to PQ's disruptive effects on binge-like alcohol drinking and associated monoamine neurochemistry and may be relevant for understanding neurodegenerative processes implicated in PD and AUD.


Asunto(s)
Consumo Excesivo de Bebidas Alcohólicas , Enfermedad de Parkinson , Ratones , Animales , Masculino , Femenino , Paraquat , Ratones Endogámicos C57BL , Consumo de Bebidas Alcohólicas , Etanol
15.
JCI Insight ; 7(4)2022 02 22.
Artículo en Inglés | MEDLINE | ID: mdl-35015729

RESUMEN

Monocyte-derived macrophages (MDMs) are key players in tissue homeostasis and diseases regulated by a variety of signaling molecules. Recent literature has highlighted the ability for biogenic amines to regulate macrophage functions, but the mechanisms governing biogenic amine signaling in and around immune cells remain nebulous. In the CNS, biogenic amine transporters are regarded as the master regulators of neurotransmitter signaling. While we and others have shown that macrophages express these transporters, relatively little is known of their function in these cells. To address these knowledge gaps, we investigated the function of norepinephrine transporter (NET) and dopamine transporter (DAT) on human MDMs. We found that both NET and DAT are present and can uptake substrate from the extracellular space at baseline. Not only was DAT expressed in cultured MDMs, but it was also detected in a subset of intestinal macrophages in situ. Surprisingly, we discovered a NET-independent, DAT-mediated immunomodulatory mechanism in response to LPS. LPS induced reverse transport of dopamine through DAT, engaging an autocrine/paracrine signaling loop that regulated the macrophage response. Removing this signaling loop enhanced the proinflammatory response to LPS. Our data introduce a potential role for DAT in the regulation of innate immunity.


Asunto(s)
Aminas Biogénicas/metabolismo , Transporte Biológico/genética , Proteínas de Transporte de Dopamina a través de la Membrana Plasmática/genética , Regulación de la Expresión Génica , Macrófagos/metabolismo , ARN/genética , Adulto , Anciano , Proteínas de Transporte de Dopamina a través de la Membrana Plasmática/biosíntesis , Proteínas de Transporte de Dopamina a través de la Membrana Plasmática/metabolismo , Femenino , Humanos , Macrófagos/patología , Masculino , Persona de Mediana Edad , Adulto Joven
16.
BMJ Open ; 11(9): e044394, 2021 09 06.
Artículo en Inglés | MEDLINE | ID: mdl-34489264

RESUMEN

INTRODUCTION: Diabetes is common (about 20 million patients in Europe) and patients with diabetes have more surgical interventions than the general population. There are plausible pathophysiological and clinical mechanisms suggesting that patients with diabetes are at an increased risk of postoperative complications. When postoperative complications occur in the general population, they increase major adverse events and subsequently increase 1-year mortality. This is likely to be worse in patients with diabetes. There is variation in practice guidelines in different countries in the perioperative management of patients with diabetes undergoing major surgery and whether this may affect postoperative outcome has not been investigated on a large scale. Neither is it known whether different strata of preoperative glycaemic control affects outcome. METHODS AND ANALYSIS: A prospective, observational, international, multicentre cohort study, recruiting 5000 patients with diabetes undergoing elective or emergency surgery in at least n=50 centres. Inclusion criteria are any patient with diabetes undergoing surgery under any substantive anaesthetic technique. Exclusion criteria are not being a confirmed diabetic patient and patients with diabetes undergoing procedures under monitored sedation or local anaesthetic infiltration only. Follow-up duration is 30 days after surgery. Primary outcome is days at home at 30 days. Secondary outcomes are Comprehensive Complications Index, Quality of Recovery (QoR-15) score on Day 1 postoperatively, 30-day mortality, length of hospital stay and incidence of specific major adverse events (Myocardial Infarction (MI), Myocardial Injury after Non-cardiac Surgery (MINS), Acute Kidney Injury (AKI), Postoperative Pulmonary Complications (PPC), Cerebrovascular Accident (CVA), Pulmonary Embolism (PE), DVT, surgical site infection, postoperative pulmonary infection). Tertiary outcomes include time to resumption of normal diabetes therapy, incidence of diabetic ketoacidosis or hypoglycaemia, incidence and duration of use of intravenous insulin infusion therapy and change in diabetic management at 30 days. ETHICS AND DISSEMINATION: This study will adhere to the principles of the Declaration of Helsinki (amendment 2013) by the World Medical Association and the ICH-Good Clinical Practice (GCP) Guidelines E6(R2). Specific national and local regulatory authority requirements will be followed as applicable. Ethical approval has been granted by the Institutional Review Board of the Mater Misericordiae University Hospital, Dublin, Ireland (Reference: 1/378/2167). As enrolment for this study is ongoing, ethical approval from additional centres is being added continuously. The main results of Management and Outcomes of Perioperative Care among European Diabetic Patients and its substudies will be published in peer-reviewed international medical journals and presented at Euroanaesthesia congress and other international and national meetings. TRIAL REGISTRATION NUMBER: NCT04511312.


Asunto(s)
Diabetes Mellitus , Motocicletas , Anestesia Local , Estudios de Cohortes , Diabetes Mellitus/tratamiento farmacológico , Diabetes Mellitus/epidemiología , Humanos , Atención Perioperativa , Complicaciones Posoperatorias/epidemiología , Estudios Prospectivos
17.
Mult Scler J Exp Transl Clin ; 5(3): 2055217319871582, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31523449

RESUMEN

BACKGROUND: The association of peripapillary retinal nerve fibre layer (pRNFL) and ganglion cell-inner plexiform layer (GCIPL) thickness with neurodegeneration in multiple sclerosis (MS) is well established. The relationship of the adjoining inner nuclear layer (INL) with inflammatory disease activity is less well understood. OBJECTIVE: The objective of this paper is to investigate the relationship of INL volume changes with inflammatory disease activity in MS.Methods In this longitudinal, multi-centre study, optical coherence tomography (OCT) and clinical data (disability status, relapses and MS optic neuritis (MSON)) were collected in 785 patients with MS (68.3% female) and 92 healthy controls (63.4% female) from 11 MS centres between 2010 and 2017 and pooled retrospectively. Data on pRNFL, GCIPL and INL were obtained at each centre. RESULTS: There was a significant increase in INL volume in eyes with new MSON during the study (N = 61/1562, ß = 0.01 mm3, p < .001). Clinical relapses (other than MSON) were significantly associated with increased INL volume (ß = 0.005, p = .025). INL volume was independent of disease progression (ß = 0.002 mm3, p = .474). CONCLUSION: Our data demonstrate that an increase in INL volume is associated with MSON and the occurrence of clinical relapses. Therefore, INL volume changes may be useful as an outcome marker for inflammatory disease activity in MSON and MS treatment trials.

18.
Neurol Neuroimmunol Neuroinflamm ; 5(3): e449, 2018 May.
Artículo en Inglés | MEDLINE | ID: mdl-29552598

RESUMEN

OBJECTIVE: To evaluate the inter-rater reliability of semiautomated segmentation of spectral domain optical coherence tomography (OCT) macular volume scans. METHODS: Macular OCT volume scans of left eyes from 17 subjects (8 patients with MS and 9 healthy controls) were automatically segmented by Heidelberg Eye Explorer (v1.9.3.0) beta-software (Spectralis Viewing Module v6.0.0.7), followed by manual correction by 5 experienced operators from 5 different academic centers. The mean thicknesses within a 6-mm area around the fovea were computed for the retinal nerve fiber layer, ganglion cell layer (GCL), inner plexiform layer (IPL), inner nuclear layer, outer plexiform layer (OPL), and outer nuclear layer (ONL). Intraclass correlation coefficients (ICCs) were calculated for mean layer thickness values. Spatial distribution of ICC values for the segmented volume scans was investigated using heat maps. RESULTS: Agreement between raters was good (ICC > 0.84) for all retinal layers, particularly inner retinal layers showed excellent agreement across raters (ICC > 0.96). Spatial distribution of ICC showed highest values in the perimacular area, whereas the ICCs were poorer for the foveola and the more peripheral macular area. The automated segmentation of the OPL and ONL required the most correction and showed the least agreement, whereas differences were less prominent for the remaining layers. CONCLUSIONS: Automated segmentation with manual correction of macular OCT scans is highly reliable when performed by experienced raters and can thus be applied in multicenter settings. Reliability can be improved by restricting analysis to the perimacular area and compound segmentation of GCL and IPL.

19.
J Neurol Sci ; 394: 1-5, 2018 11 15.
Artículo en Inglés | MEDLINE | ID: mdl-30193154

RESUMEN

OBJECTIVE: The Mobile Universal Lexicon Evaluation System (MULES) is a test of rapid picture naming that is under investigation for concussion. MULES captures an extensive visual network, including pathways for eye movements, color perception, memory and object recognition. The purpose of this study was to introduce the MULES to visual assessment of patients with MS, and to examine associations with other tests of afferent and efferent visual function. METHODS: We administered the MULES in addition to binocular measures of low-contrast letter acuity (LCLA), high-contrast visual acuity (VA) and the King-Devick (K-D) test of rapid number naming in an MS cohort and in a group of disease-free controls. RESULTS: Among 24 patients with MS (median age 36 years, range 20-72, 64% female) and 22 disease-free controls (median age 34 years, range 19-59, 57% female), MULES test times were greater (worse) among the patients (60.0 vs. 40.0 s). Accounting for age, MS vs. control status was a predictor of MULES test times (P = .01, logistic regression). Faster testing times were noted among patients with MS who had greater (better) performance on binocular LCLA at 2.5% contrast (P < .001, linear regression, accounting for age), binocular high-contrast VA (P < .001), and K-D testing (P < .001). Both groups demonstrated approximately 10-s improvements in MULES test times between trials 1 and 2 (P < .0001, paired t-tests). CONCLUSION: The MULES test, a complex task of rapid picture naming involves an extensive visual network that captures eye movements, color perception and the characterization of objects. Color recognition, a key component of this novel assessment, is early in object processing and requires area V4 and the inferior temporal projections. MULES scores reflect performance of LCLA, a widely-used measure of visual function in MS clinical trials. These results provide evidence that the MULES test can add efficient visual screening to the assessment of patients with MS.


Asunto(s)
Lenguaje , Aplicaciones Móviles , Esclerosis Múltiple/fisiopatología , Nombres , Adulto , Factores de Edad , Anciano , Femenino , Humanos , Modelos Lineales , Masculino , Persona de Mediana Edad , Estimulación Luminosa , Pruebas de Visión , Agudeza Visual , Adulto Joven
20.
J Neurol Sci ; 387: 199-204, 2018 04 15.
Artículo en Inglés | MEDLINE | ID: mdl-29571863

RESUMEN

OBJECTIVE: Measures of rapid automatized naming (RAN) have been used for over 50 years to capture vision-based aspects of cognition. The Mobile Universal Lexicon Evaluation System (MULES) is a test of rapid picture naming under investigation for detection of concussion and other neurological disorders. MULES was designed as a series of 54 grouped color photographs (fruits, random objects, animals) that integrates saccades, color perception and contextual object identification. Recent changes to the MULES test have been made to improve ease of use on the athletic sidelines. Originally an 11 × 17-inch single-sided paper, the test has been reduced to a laminated 8.5 × 11-inch double-sided version. We identified performance changes associated with transition to the new, MULES, now sized for the sidelines, and examined MULES on the sideline for sports-related concussion. METHODS: We administered the new laminated MULES to a group of adult office volunteers as well as youth and collegiate athletes during pre-season baseline testing. Athletes with concussion underwent sideline testing after injury. Time scores for the new laminated MULES were compared to those for the larger version (big MULES). RESULTS: Among 501 athletes and office volunteers (age 16 ±â€¯7 years, range 6-59, 29% female), average test times at baseline were 44.4 ±â€¯14.4 s for the new laminated MULES (n = 196) and 46.5 ±â€¯16.3 s for big MULES (n = 248). Both versions were completed by 57 participants, with excellent agreement (p < 0.001, linear regression, accounting for age). Age was a predictor of test times for both MULES versions, with longer times noted for younger participants (p < 0.001). Among 6 athletes with concussion thus far during the fall sports season (median age 15 years, range 11-21) all showed worsening of MULES scores from pre-season baseline (median 4.0 s, range 2.1-16.4). CONCLUSION: The MULES test has been converted to an 11 × 8.5-inch laminated version, with excellent agreement between versions across age groups. Feasibly administered at pre-season and in an office setting, the MULES test shows preliminary evidence of capacity to identify athletes with sports-related concussion.


Asunto(s)
Traumatismos en Atletas/complicaciones , Conmoción Encefálica/diagnóstico , Conmoción Encefálica/etiología , Nombres , Movimientos Sacádicos/fisiología , Semántica , Adolescente , Adulto , Traumatismos en Atletas/diagnóstico , Niño , Femenino , Humanos , Masculino , Persona de Mediana Edad , Aplicaciones Móviles , Pruebas Neuropsicológicas , Estimulación Luminosa , Adulto Joven
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