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1.
J Neurosci ; 43(11): 2002-2020, 2023 03 15.
Artículo en Inglés | MEDLINE | ID: mdl-36759195

RESUMEN

Cyclin-dependent kinase-like 5 (CDKL5) deficiency disorder (CDD) is a severe early-onset epileptic encephalopathy resulting mainly from de novo mutations in the X-linked CDKL5 gene. To determine whether loss of presynaptic CDKL5 function contributes to CDD, we examined synaptic vesicle (SV) recycling in primary hippocampal neurons generated from Cdkl5 knockout rat males. Using a genetically encoded reporter, we revealed that CDKL5 is selectively required for efficient SV endocytosis. We showed that CDKL5 kinase activity is both necessary and sufficient for optimal SV endocytosis, since kinase-inactive mutations failed to correct endocytosis in Cdkl5 knockout neurons, whereas the isolated CDKL5 kinase domain fully restored SV endocytosis kinetics. Finally, we demonstrated that CDKL5-mediated phosphorylation of amphiphysin 1, a putative presynaptic target, is not required for CDKL5-dependent control of SV endocytosis. Overall, our findings reveal a key presynaptic role for CDKL5 kinase activity and enhance our insight into how its dysfunction may culminate in CDD.SIGNIFICANCE STATEMENT Loss of cyclin-dependent kinase like 5 (CDKL5) function is a leading cause of monogenic childhood epileptic encephalopathy. However, information regarding its biological role is scarce. In this study, we reveal a selective presynaptic role for CDKL5 in synaptic vesicle endocytosis and that its protein kinase activity is both necessary and sufficient for this role. The isolated protein kinase domain is sufficient to correct this loss of function, which may facilitate future gene therapy strategies if presynaptic dysfunction is proven to be central to the disorder. It also reveals that a CDKL5-specific substrate is located at the presynapse, the phosphorylation of which is required for optimal SV endocytosis.


Asunto(s)
Espasmos Infantiles , Vesículas Sinápticas , Animales , Masculino , Ratas , Quinasas Ciclina-Dependientes/metabolismo , Endocitosis/fisiología , Espasmos Infantiles/genética , Espasmos Infantiles/metabolismo , Vesículas Sinápticas/metabolismo
2.
J Neurochem ; 2024 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-39091022

RESUMEN

Following exocytosis, the recapture of plasma membrane-stranded vesicular proteins into recycling synaptic vesicles (SVs) is essential for sustaining neurotransmission. Surface clustering of vesicular proteins has been proposed to act as a 'pre-assembly' mechanism for endocytosis that ensures high-fidelity retrieval of SV cargo. Here, we used single-molecule imaging to examine the nanoclustering of synaptotagmin-1 (Syt1) and synaptic vesicle protein 2A (SV2A) in hippocampal neurons. Syt1 forms surface nanoclusters through the interaction of its C2B domain with SV2A, which are sensitive to mutations in this domain (Syt1K326A/K328A) and SV2A knockdown. SV2A co-clustering with Syt1 is reduced by blocking SV2A's cognate interaction with Syt1 (SV2AT84A). Surprisingly, impairing SV2A-Syt1 nanoclustering enhanced the plasma membrane recruitment of key endocytic protein dynamin-1, causing accelerated Syt1 endocytosis, altered intracellular sorting and decreased trafficking of Syt1 to Rab5-positive endocytic compartments. Therefore, SV2A and Syt1 are segregated from the endocytic machinery in surface nanoclusters, limiting dynamin recruitment and negatively regulating Syt1 entry into recycling SVs.

3.
Europace ; 25(5)2023 05 19.
Artículo en Inglés | MEDLINE | ID: mdl-37208301

RESUMEN

Remote monitoring is beneficial for the management of patients with cardiovascular implantable electronic devices by impacting morbidity and mortality. With increasing numbers of patients using remote monitoring, keeping up with higher volume of remote monitoring transmissions creates challenges for device clinic staff. This international multidisciplinary document is intended to guide cardiac electrophysiologists, allied professionals, and hospital administrators in managing remote monitoring clinics. This includes guidance for remote monitoring clinic staffing, appropriate clinic workflows, patient education, and alert management. This expert consensus statement also addresses other topics such as communication of transmission results, use of third-party resources, manufacturer responsibilities, and programming concerns. The goal is to provide evidence-based recommendations impacting all aspects of remote monitoring services. Gaps in current knowledge and guidance for future research directions are also identified.


Asunto(s)
Monitoreo Fisiológico , Telemetría , Humanos
4.
MMWR Morb Mortal Wkly Rep ; 71(43): 1366-1373, 2022 Oct 28.
Artículo en Inglés | MEDLINE | ID: mdl-36302226

RESUMEN

Introduction: CDC estimates that influenza resulted in 9-41 million illnesses, 140,000-710,000 hospitalizations, and 12,000-52,000 deaths annually during 2010-2020. Persons from some racial and ethnic minority groups have historically experienced higher rates of severe influenza and had lower influenza vaccination coverage compared with non-Hispanic White (White) persons. This report examines influenza hospitalization and vaccination rates by race and ethnicity during a 12-13-year period (through the 2021-22 influenza season). Methods: Data from population-based surveillance for laboratory-confirmed influenza-associated hospitalizations in selected states participating in the Influenza-Associated Hospitalization Surveillance Network (FluSurv-NET) from the 2009-10 through 2021-22 influenza seasons (excluding 2020-21) and influenza vaccination coverage data from the Behavioral Risk Factor Surveillance System (BRFSS) from the 2010-11 through 2021-22 influenza seasons were analyzed by race and ethnicity. Results: From 2009-10 through 2021-22, age-adjusted influenza hospitalization rates (hospitalizations per 100,000 population) were higher among non-Hispanic Black (Black) (rate ratio [RR] = 1.8), American Indian or Alaska Native (AI/AN; RR = 1.3), and Hispanic (RR = 1.2) adults, compared with the rate among White adults. During the 2021-22 season, influenza vaccination coverage was lower among Hispanic (37.9%), AI/AN (40.9%), Black (42.0%), and other/multiple race (42.6%) adults compared with that among White (53.9%) and non-Hispanic Asian (Asian) (54.2%) adults; coverage has been consistently higher among White and Asian adults compared with that among Black and Hispanic adults since the 2010-11 season. The disparity in vaccination coverage by race and ethnicity was present among those who reported having medical insurance, a personal health care provider, and a routine medical checkup in the past year. Conclusions and Implications for Public Health Practice: Racial and ethnic disparities in influenza disease severity and influenza vaccination coverage persist. Health care providers should assess patient vaccination status at all medical visits and offer (or provide a referral for) all recommended vaccines. Tailored programmatic efforts to provide influenza vaccination through nontraditional settings, along with national and community-level efforts to improve awareness of the importance of influenza vaccination in preventing illness, hospitalization, and death among racial and ethnic minority communities might help address health care access barriers and improve vaccine confidence, leading to decreases in disparities in influenza vaccination coverage and disease severity.


Asunto(s)
Vacunas contra la Influenza , Gripe Humana , Adulto , Estados Unidos/epidemiología , Humanos , Gripe Humana/epidemiología , Gripe Humana/prevención & control , Etnicidad , Estaciones del Año , Cobertura de Vacunación , Grupos Minoritarios , Vacunación , Hospitalización , Signos Vitales
5.
J Immunol ; 205(1): 78-89, 2020 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-32414808

RESUMEN

Class I PI3K enzymes are critical for the maintenance of effective immunity. In T cells, PI3Kα and PI3Kδ are activated by the TCR and costimulatory receptors, whereas PI3Kγ is activated by G protein-coupled chemokine receptors. PI3Kδ is a key regulator of regulatory T (Treg) cell function. PI3K isoform-selective inhibitors are in development for the treatment of diseases associated with immune dysregulation, including chronic inflammatory conditions, cancer, and autoimmune diseases. Idelalisib (PI3Kδ), alpelisib (PI3Kα), duvelisib (PI3Kδ/γ), and copanlisib (pan-PI3K) have recently been approved for use in cancer treatment. Although effective, these therapies often have severe side effects associated with immune dysregulation and, in particular, loss of Treg cells. Therefore, it is important to gain a better understanding of the relative contribution of different PI3K isoforms under homeostatic and inflammatory conditions. Experimental autoimmune encephalitis is a mouse model of T cell-driven CNS inflammation, in which Treg cells play a key protective role. In this study, we show that PI3Kδ is required to maintain normal Treg cell development and phenotype under homeostatic conditions but that loss of PI3Kδ alone in Treg cells does not lead to autoimmunity. However, combined loss of PI3Kα and PI3Kδ signaling resulted in increased experimental autoimmune encephalitis disease severity. Moreover, mice lacking PI3Kα and PI3Kδ in Treg cells developed spontaneous peripheral nerve inflammation. These results show a key role for PI3K signaling in Treg cell-mediated protection against CNS inflammation.


Asunto(s)
Fosfatidilinositol 3-Quinasa Clase I/metabolismo , Fosfatidilinositol 3-Quinasa Clase Ib/metabolismo , Encefalomielitis Autoinmune Experimental/inmunología , Nervios Periféricos/inmunología , Linfocitos T Reguladores/inmunología , Animales , Autoinmunidad/genética , Fosfatidilinositol 3-Quinasa Clase I/genética , Fosfatidilinositol 3-Quinasa Clase Ib/genética , Encefalomielitis Autoinmune Experimental/sangre , Encefalomielitis Autoinmune Experimental/diagnóstico , Encefalomielitis Autoinmune Experimental/patología , Femenino , Humanos , Masculino , Ratones , Ratones Transgénicos , Glicoproteína Mielina-Oligodendrócito/administración & dosificación , Glicoproteína Mielina-Oligodendrócito/inmunología , Fragmentos de Péptidos/administración & dosificación , Fragmentos de Péptidos/inmunología , Nervios Periféricos/patología , Índice de Severidad de la Enfermedad , Transducción de Señal/genética , Transducción de Señal/inmunología , Linfocitos T Reguladores/metabolismo
6.
J Neurosci ; 40(23): 4586-4595, 2020 06 03.
Artículo en Inglés | MEDLINE | ID: mdl-32341095

RESUMEN

The epilepsy-linked gene SV2A, has a number of potential roles in the synaptic vesicle (SV) life cycle. However, how loss of SV2A function translates into presynaptic dysfunction and ultimately seizure activity is still undetermined. In this study, we examined whether the first SV2A mutation identified in human disease (R383Q) could provide information regarding which SV2A-dependent events are critical in the translation to epilepsy. We utilized a molecular replacement strategy in which exogenous SV2A was expressed in mouse neuronal cultures of either sex, which had been depleted of endogenous SV2A to mimic the homozygous human condition. We found that the R383Q mutation resulted in a mislocalization of SV2A from SVs to the plasma membrane, but had no effect on its activity-dependent trafficking. This SV2A mutant displayed reduced mobility when stranded on the plasma membrane and reduced binding to its interaction partner synaptotagmin-1 (Syt1). Furthermore, the R383Q mutant failed to rescue reduced expression and dysfunctional activity-dependent trafficking of Syt1 in the absence of endogenous SV2A. This suggests that the inability to control Syt1 expression and trafficking at the presynapse may be key in the transition from loss of SV2A function to seizure activity.SIGNIFICANCE STATEMENT SV2A is a synaptic vesicle (SV) protein, the absence or dysfunction of which is linked to epilepsy. However, the series of molecular events that result in this neurological disorder is still undetermined. We demonstrate here that the first human mutation in SV2A identified in an individual with epilepsy displays reduced binding to synaptotagmin-1 (Syt1), an SV protein essential for synchronous neurotransmitter release. Furthermore, this mutant cannot correct alterations in both Syt1 expression and trafficking when expressed in the absence of endogenous SV2A (to mimic the homozygous human condition). This suggests that the inability to control Syt1 expression and trafficking may be key in the transition from loss of SV2A function to seizure activity.


Asunto(s)
Epilepsia/genética , Glicoproteínas de Membrana/genética , Mutación Missense/fisiología , Proteínas del Tejido Nervioso/genética , Transporte de Proteínas/fisiología , Sinaptotagmina I/biosíntesis , Sinaptotagmina I/genética , Animales , Células Cultivadas , Epilepsia/metabolismo , Femenino , Expresión Génica , Células HEK293 , Humanos , Masculino , Glicoproteínas de Membrana/deficiencia , Ratones , Ratones Endogámicos C57BL , Proteínas del Tejido Nervioso/deficiencia
7.
Neuroimage ; 241: 118402, 2021 11 01.
Artículo en Inglés | MEDLINE | ID: mdl-34274419

RESUMEN

Magnetoencephalography (MEG) is a functional neuroimaging tool that records the magnetic fields induced by neuronal activity; however, signal from non-neuronal sources can corrupt the data. Eye-blinks, saccades, and cardiac activity are three of the most common sources of non-neuronal artifacts. They can be measured by affixing eye proximal electrodes, as in electrooculography (EOG), and chest electrodes, as in electrocardiography (ECG), however this complicates imaging setup, decreases patient comfort, and can induce further artifacts from movement. This work proposes an EOG- and ECG-free approach to identify eye-blinks, saccades, and cardiac activity signals for automated artifact suppression. The contribution of this work is three-fold. First, using a data driven, multivariate decomposition approach based on Independent Component Analysis (ICA), a highly accurate artifact classifier is constructed as an amalgam of deep 1-D and 2-D Convolutional Neural Networks (CNNs) to automate the identification and removal of ubiquitous whole brain artifacts including eye-blink, saccade, and cardiac artifacts. The specific architecture of this network is optimized through an unbiased, computer-based hyperparameter random search. Second, visualization methods are applied to the learned abstraction to reveal what features the model uses and to bolster user confidence in the model's training and potential for generalization. Finally, the model is trained and tested on both resting-state and task MEG data from 217 subjects, and achieves a new state-of-the-art in artifact detection accuracy of 98.95% including 96.74% sensitivity and 99.34% specificity on the held out test-set. This work automates MEG processing for both clinical and research use, adapts to the acquired acquisition time, and can obviate the need for EOG or ECG electrodes for artifact detection.


Asunto(s)
Artefactos , Encéfalo/fisiología , Magnetoencefalografía/métodos , Redes Neurales de la Computación , Procesamiento de Señales Asistido por Computador , Adolescente , Adulto , Anciano , Parpadeo/fisiología , Niño , Femenino , Humanos , Magnetoencefalografía/normas , Masculino , Persona de Mediana Edad , Adulto Joven
8.
J Neurochem ; 157(2): 179-207, 2021 04.
Artículo en Inglés | MEDLINE | ID: mdl-32378740

RESUMEN

The activity-dependent fusion, retrieval and recycling of synaptic vesicles is essential for the maintenance of neurotransmission. Until relatively recently it was believed that most mutations in genes that were essential for this process would be incompatible with life, because of this fundamental role. However, an ever-expanding number of mutations in this very cohort of genes are being identified in individuals with neurodevelopmental disorders, including autism, intellectual disability and epilepsy. This article will summarize the current state of knowledge linking mutations in presynaptic genes to neurodevelopmental disorders by sequentially covering the various stages of the synaptic vesicle life cycle. It will also discuss how perturbations of specific stages within this recycling process could translate into human disease. Finally, it will also provide perspectives on the potential for future therapy that are targeted to presynaptic function.


Asunto(s)
Terminales Presinápticos/metabolismo , Sinapsis/metabolismo , Transmisión Sináptica/fisiología , Vesículas Sinápticas/metabolismo , Animales , Endocitosis/fisiología , Exocitosis/fisiología , Humanos
9.
Hum Brain Mapp ; 42(8): 2529-2545, 2021 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-33734521

RESUMEN

Repetitive head impact (RHI) exposure in collision sports may contribute to adverse neurological outcomes in former players. In contrast to a concussion, or mild traumatic brain injury, "subconcussive" RHIs represent a more frequent and asymptomatic form of exposure. The neural network-level signatures characterizing subconcussive RHIs in youth collision-sport cohorts such as American Football are not known. Here, we used resting-state functional MRI to examine default mode network (DMN) functional connectivity (FC) following a single football season in youth players (n = 50, ages 8-14) without concussion. Football players demonstrated reduced FC across widespread DMN regions compared with non-collision sport controls at postseason but not preseason. In a subsample from the original cohort (n = 17), players revealed a negative change in FC between preseason and postseason and a positive and compensatory change in FC during the offseason across the majority of DMN regions. Lastly, significant FC changes, including between preseason and postseason and between in- and off-season, were specific to players at the upper end of the head impact frequency distribution. These findings represent initial evidence of network-level FC abnormalities following repetitive, non-concussive RHIs in youth football. Furthermore, the number of subconcussive RHIs proved to be a key factor influencing DMN FC.


Asunto(s)
Traumatismos en Atletas/fisiopatología , Conmoción Encefálica/fisiopatología , Corteza Cerebral/fisiopatología , Conectoma , Red en Modo Predeterminado/fisiopatología , Adolescente , Traumatismos en Atletas/diagnóstico por imagen , Conmoción Encefálica/diagnóstico por imagen , Corteza Cerebral/diagnóstico por imagen , Niño , Red en Modo Predeterminado/diagnóstico por imagen , Femenino , Fútbol Americano , Humanos , Imagen por Resonancia Magnética , Masculino
10.
J Am Pharm Assoc (2003) ; 60(3S): S20-S28.e4, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32094038

RESUMEN

OBJECTIVES: The study aim was to characterize the Indiana community-based pharmacist preceptors' knowledge and perceptions of medication-assisted treatment (MAT) for opioid use disorder (OUD). The secondary objectives were to explore the desired resources, dispensing concerns, and preceptors' involvement in precepting students. DESIGN: A 38-item survey was used to collect respondent demographics, knowledge, and perceptions of MAT for OUD. Perception questions were developed using the social cognitive theory and were adapted from previously published surveys with investigators' permission. SETTING: Community-based Indiana pharmacist preceptors were eligible to complete an electronic survey in February and March 2019. OUTCOME MEASURES: Descriptive statistics were used to characterize preceptor knowledge and perceptions of MAT for OUD. Desired MAT resources, dispensing concerns, and level of involvement in precepting students were collected. Respondent demographics were collected to characterize the study sample. RESULTS: Of the 116 survey responses, 104 were eligible, and 79 community-based pharmacist preceptors completed the survey, yielding a response rate of 76.0%. For knowledge questions, the overall correct score was 56.2%. Respondents had high correct scores on questions related to medication access. However, respondents either self-identified or performed poorly on the following knowledge items: Food and Drug Administration-approved MAT products for OUD, the need to provide an opioid-free interval before initiating treatment with buprenorphine and naltrexone, pregnancy recommendations, and treatment of severe OUD. Respondents reported positive perceptions on MAT for OUD, but identified concerns regarding diversion and misuse of MAT. Most respondents reported a desire for additional education on different aspects of MAT for OUD. Dispensing concerns and preceptors' involvement with students in MAT ranged from no concern and lack of involvement to many different concerns and full student involvement. CONCLUSION: Opportunities exist to fill identified gaps in knowledge, enhance perceptions, and provide desired continuing education for community-based pharmacist preceptors on MAT for OUD.


Asunto(s)
Farmacéuticos , Preceptoría , Educación Continua , Humanos , Indiana , Percepción , Encuestas y Cuestionarios
11.
Magn Reson Med ; 80(6): 2402-2414, 2018 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-29707813

RESUMEN

PURPOSE: To compare the recently introduced inhomogeneous magnetization transfer (ihMT) technique with more established MRI techniques including myelin water imaging (MWI) and diffusion tensor imaging (DTI), and to evaluate the microstructural attributes correlating with this new contrast method in the human brain white matter. METHODS: Eight adult healthy volunteers underwent T1 -weighted, ihMT, MWI, and DTI imaging on a 3T human scanner. The ihMT ratio (ihMTR), myelin water fraction (MWF), fractional anisotropy (FA), radial diffusivity (RD), axial diffusivity (AD), and mean diffusivity (MD) values were calculated from different white matter tracts. The angle ( θ ) between the directions of the principal eigenvector, as measured by DTI, and the main magnetic field was calculated for all voxels from various fiber tracts. The ihMTR was correlated with MWF and DTI metrics. RESULTS: A strong correlation was found between ihMTR and MWF (ρ = 0.77, P < 0.0001). This was followed by moderate to weak correlations between ihMTR and DTI metrics: RD (ρ = -0.30, P < 0.0001), FA (ρ = 0.20, P < 0.0001), MD (ρ = -0.19, P < 0.0001), AD (ρ = 0.02, P < 0.0001). A strong correlation was found between ihMTR and θ (ρ = -0.541, P < 0.0001). CONCLUSION: The strong correlation with myelin water imaging and its low coefficient of variation suggest that ihMT has the potential to become a new structural imaging marker of myelin. The substantial orientational dependence of ihMT should be taken into account when evaluating and quantitatively interpreting ihMT results.


Asunto(s)
Encéfalo/diagnóstico por imagen , Imagen de Difusión por Resonancia Magnética , Imagenología Tridimensional/métodos , Vaina de Mielina/química , Sustancia Blanca/diagnóstico por imagen , Adulto , Anisotropía , Mapeo Encefálico/métodos , Simulación por Computador , Imagen de Difusión Tensora , Femenino , Voluntarios Sanos , Humanos , Procesamiento de Imagen Asistido por Computador , Magnetismo , Masculino , Reconocimiento de Normas Patrones Automatizadas , Programas Informáticos , Agua , Adulto Joven
12.
J Neurochem ; 137(4): 518-27, 2016 05.
Artículo en Inglés | MEDLINE | ID: mdl-26865271

RESUMEN

Mint/X11 is one of the four neuronal trafficking adaptors that interact with amyloid precursor protein (APP) and are linked with its cleavage to generate ß-amyloid peptide, a key player in the pathology of Alzheimer's disease. How APP switches between adaptors at different stages of the secretory pathway is poorly understood. Here, we show that tyrosine phosphorylation of Mint1 regulates the destination of APP. A canonical SH2-binding motif ((202) YEEI) was identified in the N-terminus of Mint1 that is phosphorylated on tyrosine by C-Src and recruits the active kinase for sequential phosphorylation of further tyrosines (Y191 and Y187). A single Y202F mutation in the Mint1 N-terminus inhibits C-Src binding and tyrosine phosphorylation. Previous studies observed that co-expression of wild-type Mint1 and APP causes accumulation of APP in the trans-Golgi. Unphosphorylatable Mint1 (Y202F) or pharmacological inhibition of Src reduced the accumulation of APP in the trans-Golgi of heterologous cells. A similar result was observed in cultured rat hippocampal neurons where Mint1(Y202F) permitted the trafficking of APP to more distal neurites than the wild-type protein. These data underline the importance of the tyrosine phosphorylation of Mint1 as a critical switch for determining the destination of APP. The regulation of amyloid precursor protein (APP) trafficking is poorly understood. We have discovered that the APP adapter, Mint1, is phosphorylated by C-Src kinase. Mint1 causes APP accumulation in the trans-Golgi network, whereas inhibition of Src or mutation of Mint1-Y202 permits APP recycling. The phosphorylation status of Mint1 could impact on the pathological trafficking of APP in Alzheimer's disease.


Asunto(s)
Proteínas Adaptadoras Transductoras de Señales/metabolismo , Precursor de Proteína beta-Amiloide/metabolismo , Proteínas del Tejido Nervioso/metabolismo , Tirosina/metabolismo , Familia-src Quinasas/metabolismo , Red trans-Golgi/metabolismo , Proteínas Adaptadoras Transductoras de Señales/genética , Secuencia de Aminoácidos , Precursor de Proteína beta-Amiloide/genética , Animales , Células COS , Células Cultivadas , Chlorocebus aethiops , Femenino , Células HeLa , Humanos , Masculino , Ratones , Proteínas del Tejido Nervioso/genética , Fosforilación/fisiología , Transporte de Proteínas/fisiología , Ratas , Ratas Wistar , Tirosina/genética , Familia-src Quinasas/genética , Red trans-Golgi/genética
13.
Radiology ; 281(3): 919-926, 2016 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-27775478

RESUMEN

Purpose To examine the effects of subconcussive impacts resulting from a single season of youth (age range, 8-13 years) football on changes in specific white matter (WM) tracts as detected with diffusion-tensor imaging in the absence of clinically diagnosed concussions. Materials and Methods Head impact data were recorded by using the Head Impact Telemetry system and quantified as the combined-probability risk-weighted cumulative exposure (RWECP). Twenty-five male participants were evaluated for seasonal fractional anisotropy (FA) changes in specific WM tracts: the inferior fronto-occipital fasciculus (IFOF), inferior longitudinal fasciculus, and superior longitudinal fasciculus (SLF). Fiber tracts were segmented into a central core and two fiber terminals. The relationship between seasonal FA change in the whole fiber, central core, and the fiber terminals with RWECP was also investigated. Linear regression analysis was conducted to determine the association between RWECP and change in fiber tract FA during the season. Results There were statistically significant linear relationships between RWEcp and decreased FA in the whole (R2 = 0.433; P = .003), core (R2 = 0.3649; P = .007), and terminals (R2 = 0.5666; P < .001) of left IFOF. A trend toward statistical significance (P = .08) in right SLF was observed. A statistically significant correlation between decrease in FA of the right SLF terminal and RWECP was also observed (R2 = 0.2893; P = .028). Conclusion This study found a statistically significant relationship between head impact exposure and change of FA fractional anisotropy value of whole, core, and terminals of left IFOF and right SLF's terminals where WM and gray matter intersect, in the absence of a clinically diagnosed concussion. © RSNA, 2016.


Asunto(s)
Conmoción Encefálica/patología , Fútbol Americano/lesiones , Traumatismos Cerrados de la Cabeza/patología , Sustancia Blanca/patología , Adolescente , Niño , Imagen de Difusión Tensora , Lóbulo Frontal/patología , Humanos , Masculino , Fibras Nerviosas Mielínicas/patología , Vías Nerviosas/patología , Lóbulo Occipital/patología
14.
Neuroimage ; 96: 88-94, 2014 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-24699016

RESUMEN

Interhemispheric connectivity with resting state MEG has been elusive, and demonstration of the default mode network (DMN) yet more challenging. Recent seed-based MEG analyses have shown interhemispheric connectivity using power envelope correlations. The purpose of this study is to compare graph theoretic maps of brain connectivity generated using MEG with and without signal leakage correction to evaluate for the presence of interhemispheric connectivity. Eight minutes of resting state eyes-open MEG data were obtained in 22 normal male subjects enrolled in an IRB-approved study (ages 16-18). Data were processed using an in-house automated MEG processing pipeline and projected into standard (MNI) source space at 7mm resolution using a scalar beamformer. Mean beta-band amplitude was sampled at 2.5second epochs from the source space time series. Leakage correction was performed in the time domain of the source space beam formed signal prior to amplitude transformation. Graph theoretic voxel-wise source space correlation connectivity analysis was performed for leakage corrected and uncorrected data. Degree maps were thresholded across subjects for the top 20% of connected nodes to identify hubs. Additional degree maps for sensory, visual, motor, and temporal regions were generated to identify interhemispheric connectivity using laterality indices. Hubs for the uncorrected MEG networks were predominantly symmetric and midline, bearing some resemblance to fMRI networks. These included the cingulate cortex, bilateral inferior frontal lobes, bilateral hippocampal formations and bilateral cerebellar hemispheres. These uncorrected networks however, demonstrated little to no interhemispheric connectivity using the ROI-based degree maps. Leakage corrected MEG data identified the DMN, with hubs in the posterior cingulate and biparietal areas. These corrected networks demonstrated robust interhemispheric connectivity for the ROI-based degree maps. Graph theoretic analysis of MEG resting state data without signal leakage correction can demonstrate symmetric networks with some resemblance to fMRI networks. These networks however, are an artifact of high local correlation from signal leakage and lack interhemispheric connectivity. Following signal leakage correction, MEG hubs emerge in the DMN, with strong interhemispheric connectivity.


Asunto(s)
Algoritmos , Cerebro/fisiología , Conectoma/métodos , Interpretación de Imagen Asistida por Computador/métodos , Magnetoencefalografía/métodos , Red Nerviosa/fisiología , Descanso/fisiología , Adolescente , Femenino , Humanos , Aumento de la Imagen/métodos , Masculino , Vías Nerviosas/fisiología , Análisis Numérico Asistido por Computador , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
15.
Front Neurosci ; 18: 1368172, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38817913

RESUMEN

Introduction: Transcranial photobiomodulation (tPBM) is a non-invasive neuromodulation technique that improves human cognition. The effects of tPBM of the right forehead on neurophysiological activity have been previously investigated using EEG in sensor space. However, the spatial resolution of these studies is limited. Magnetoencephalography (MEG) is known to facilitate a higher spatial resolution of brain source images. This study aimed to image post-tPBM effects in brain space based on both MEG and EEG measurements across the entire human brain. Methods: MEG and EEG scans were concurrently acquired for 6 min before and after 8-min of tPBM delivered using a 1,064-nm laser on the right forehead of 25 healthy participants. Group-level changes in both the MEG and EEG power spectral density with respect to the baseline (pre-tPBM) were quantified and averaged within each frequency band in the sensor space. Constrained modeling was used to generate MEG and EEG source images of post-tPBM, followed by cluster-based permutation analysis for family wise error correction (p < 0.05). Results: The 8-min tPBM enabled significant increases in alpha (8-12 Hz) and beta (13-30 Hz) powers across multiple cortical regions, as confirmed by MEG and EEG source images. Moreover, tPBM-enhanced oscillations in the beta band were located not only near the stimulation site but also in remote cerebral regions, including the frontal, parietal, and occipital regions, particularly on the ipsilateral side. Discussion: MEG and EEG results shown in this study demonstrated that tPBM modulates neurophysiological activity locally and in distant cortical areas. The EEG topographies reported in this study were consistent with previous observations. This study is the first to present MEG and EEG evidence of the electrophysiological effects of tPBM in the brain space, supporting the potential utility of tPBM in treating neurological diseases through the modulation of brain oscillations.

16.
Brain Sci ; 14(2)2024 Feb 09.
Artículo en Inglés | MEDLINE | ID: mdl-38391747

RESUMEN

Drug-resistant epilepsy (DRE) is often treated with surgery or neuromodulation. Specifically, responsive neurostimulation (RNS) is a widely used therapy that is programmed to detect abnormal brain activity and intervene with tailored stimulation. Despite the success of RNS, some patients require further interventions. However, having an RNS device in situ is a hindrance to the performance of neuroimaging techniques. Magnetoencephalography (MEG), a non-invasive neurophysiologic and functional imaging technique, aids epilepsy assessment and surgery planning. MEG performed post-RNS is complicated by signal distortions. This study proposes an independent component analysis (ICA)-based approach to enhance MEG signal quality, facilitating improved assessment for epilepsy patients with implanted RNS devices. Three epilepsy patients, two with RNS implants and one without, underwent MEG scans. Preprocessing included temporal signal space separation (tSSS) and an automated ICA-based approach with MNE-Python. Power spectral density (PSD) and signal-to-noise ratio (SNR) were analyzed, and MEG dipole analysis was conducted using single equivalent current dipole (SECD) modeling. The ICA-based noise removal preprocessing method substantially improved the signal-to-noise ratio (SNR) for MEG data from epilepsy patients with implanted RNS devices. Qualitative assessment confirmed enhanced signal readability and improved MEG dipole analysis. ICA-based processing markedly enhanced MEG data quality in RNS patients, emphasizing its clinical relevance.

17.
Brain Imaging Behav ; 2024 May 30.
Artículo en Inglés | MEDLINE | ID: mdl-38814546

RESUMEN

Several magnetic resonance imaging (MRI) studies have reported that antidepressant medications are strongly linked to brain microstructural alterations. Notably, external capsule alterations have been reported to be a biological marker for therapeutic response. However, prior studies did not investigate whether a change in the neurite density or directional coherence of white matter (WM) fibers underlies the observed microstructural alterations. This MRI-based case-control study examined the relationship between patients' current use of antidepressant medications and advanced measurements of external capsule WM microstructure derived from multishell diffusion imaging using neurite orientation dispersion and density imaging (NODDI). The study compared a group of thirty-five participants who were taking antidepressant medications comprising selective serotonin reuptake inhibitors (SSRIs) (n = 25) and serotonin and norepinephrine reuptake inhibitors (SNRIs) with a control group of thirty-five individuals matched in terms of age, sex, race, and atherosclerotic cardiovascular risk factors. All participants were selected from the Dallas Heart Study phase 2, a multi-ethnic, population-based cohort study. A series of multiple linear regression analyses were conducted to predict microstructural characteristics of the bilateral external capsule using age, sex, and antidepressant medications as predictor variables. There was significantly reduced neurite density in the bilateral external capsules of patients taking SSRIs. Increased orientation dispersion in the external capsule was predominantly seen in patients taking SNRIs. Our findings suggest an association between specific external capsule microstructural changes and antidepressant medications, including reduced neurite density for SSRIs and increased orientation dispersion for SNRIs.

18.
Ecology ; 105(2): e4235, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38185479

RESUMEN

Outbreaks of environmentally transmitted parasites require that susceptible hosts encounter transmission stages in the environment and become infected, but we also know that transmission stages can be in the environment without triggering disease outbreaks. One challenge in understanding the relationship between environmental transmission stages and disease outbreaks is that the distribution and abundance of transmission stages outside of their hosts have been difficult to quantify. Thus, we have limited data about how changes in transmission stage abundance influence disease dynamics; moreover, we do not know whether the relationship between transmission stages and outbreaks differs among parasite species. We used digital PCR to quantify the environmental transmission stages of five parasites in six lakes in southeastern Michigan every 2 weeks from June to November 2021. At the same time, we quantified infection prevalence in hosts and host density. Our study focused on eight zooplankton host species (Daphnia spp. and Ceriodaphnia dubia) and five of their parasites from diverse taxonomic groups (bacteria, yeast, microsporidia, and oomycete) with different infection mechanisms. We found that parasite transmission stage concentration increased prior to disease outbreaks for all parasites. However, parasites differed significantly in the relative timing of peaks in transmission stage concentration and infection outbreaks. The "continuous shedder" parasites had transmission stage peaks at the same time as or slightly after the outbreak peaks. In contrast, parasites relying on host death for transmission ("obligate killers") had transmission stage peaks before outbreak peaks. For most parasites, lakes with outbreaks had higher spore concentrations than those without outbreaks, especially once an outbreak began; the exception was for a parasite, Pasteuria ramosa, with very strong genotypic specificity of infection. Overall, our results show that disease outbreaks are tightly linked to transmission stage concentration; outbreaks were preceded by increases in transmission stage concentration in the environment and then were fueled by the production of more transmission stages during the outbreak itself, with concentrations decreasing to pre-outbreak levels as outbreaks waned. Thus, tracking transmission stages in the environment improves our understanding of the drivers of disease outbreaks and reveals how parasite traits may affect these dynamics.


Asunto(s)
Parásitos , Animales , Daphnia/parasitología , Especificidad del Huésped , Brotes de Enfermedades/veterinaria , Lagos , Interacciones Huésped-Parásitos
19.
J Interv Card Electrophysiol ; 67(5): 1173-1179, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38194120

RESUMEN

BACKGROUND: With increasing constraints on healthcare resources, greater attention is being focused on improved resource utilization. Prior studies have demonstrated safety of same-day discharge following CIED implantation but are limited by vague protocols with long observation periods. In this study, we evaluate the safety of an expedited 2 hour same-day discharge protocol following CIED implantation. METHODS: Patients undergoing CIED implantation at three centers between 2015 and 2021 were included. Procedural, demographic, and adverse event data were abstracted from the electronic health record. Patients were divided into same-day discharge (SDD) and delayed discharge (DD) cohorts. The primary outcome was complications including lead malfunction requiring revision, pneumothorax, hemothorax, lead dislodgement, lead perforation with tamponade, and mortality within 30 days of procedure. Outcomes were compared between the two cohorts using the χ2 test. RESULTS: A total of 4543 CIED implantation procedures were included with 1557 patients (34%) in the SDD cohort. SDD patients were comparatively younger, were more likely to be male, and had fewer comorbidities than DD patients. Among SDD patients, the mean time to post-operative chest X-ray was 2.6 h. SDD had lower rates of complications (1.3% vs 2.1%, p = 0.0487) and acute care utilization post-discharge (9.6% vs 14.0%, p < 0.0001). There was no difference in the 90-day infection rate between the cohorts. CONCLUSIONS: An expedited 2 hour same-day discharge protocol is safe and effective with low rates of complications, infection, and post-operative acute care utilization.


Asunto(s)
Desfibriladores Implantables , Alta del Paciente , Complicaciones Posoperatorias , Humanos , Masculino , Femenino , Anciano , Complicaciones Posoperatorias/epidemiología , Marcapaso Artificial , Persona de Mediana Edad , Estudios Retrospectivos , Estudios de Cohortes , Factores de Tiempo
20.
J Imaging ; 10(4)2024 Mar 28.
Artículo en Inglés | MEDLINE | ID: mdl-38667978

RESUMEN

Magnetoencephalography (MEG) is a noninvasive neuroimaging technique widely recognized for epilepsy and tumor mapping. MEG clinical reporting requires a multidisciplinary team, including expert input regarding each dipole's anatomic localization. Here, we introduce a novel tool, the "Magnetoencephalography Atlas Viewer" (MAV), which streamlines this anatomical analysis. The MAV normalizes the patient's Magnetic Resonance Imaging (MRI) to the Montreal Neurological Institute (MNI) space, reverse-normalizes MNI atlases to the native MRI, identifies MEG dipole files, and matches dipoles' coordinates to their spatial location in atlas files. It offers a user-friendly and interactive graphical user interface (GUI) for displaying individual dipoles, groups, coordinates, anatomical labels, and a tri-planar MRI view of the patient with dipole overlays. It evaluated over 273 dipoles obtained in clinical epilepsy subjects. Consensus-based ground truth was established by three neuroradiologists, with a minimum agreement threshold of two. The concordance between the ground truth and MAV labeling ranged from 79% to 84%, depending on the normalization method. Higher concordance rates were observed in subjects with minimal or no structural abnormalities on the MRI, ranging from 80% to 90%. The MAV provides a straightforward MEG dipole anatomic localization method, allowing a nonspecialist to prepopulate a report, thereby facilitating and reducing the time of clinical reporting.

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