38 research outputs found
Para-infectious brain injury in COVID-19 persists at follow-up despite attenuated cytokine and autoantibody responses
To understand neurological complications of COVID-19 better both acutely and for recovery, we measured markers of brain injury, inflammatory mediators, and autoantibodies in 203 hospitalised participants; 111 with acute sera (1–11 days post-admission) and 92 convalescent sera (56 with COVID-19-associated neurological diagnoses). Here we show that compared to 60 uninfected controls, tTau, GFAP, NfL, and UCH-L1 are increased with COVID-19 infection at acute timepoints and NfL and GFAP are significantly higher in participants with neurological complications. Inflammatory mediators (IL-6, IL-12p40, HGF, M-CSF, CCL2, and IL-1RA) are associated with both altered consciousness and markers of brain injury. Autoantibodies are more common in COVID-19 than controls and some (including against MYL7, UCH-L1, and GRIN3B) are more frequent with altered consciousness. Additionally, convalescent participants with neurological complications show elevated GFAP and NfL, unrelated to attenuated systemic inflammatory mediators and to autoantibody responses. Overall, neurological complications of COVID-19 are associated with evidence of neuroglial injury in both acute and late disease and these correlate with dysregulated innate and adaptive immune responses acutely
Autonomic Nervous System Reactivity and Addiction Vulnerability in the African American Community
Background: African Americans experience disproportionate rates of morbidity and mortality with regard to drug use, but the mechanisms underlying this association remain poorly understood. Increasing evidence suggests that exposure to chronic stress and the subsequent activation of the physiological stress systems have been linked to the development of addiction. To date, no research exists that focuses on the influence of autonomic reactivity on prospective drug use among African American emerging adults. Purpose: The present study aimed to: (1) investigate the association between ANS reactivity and prospective drug use among a sample of African American emerging adults (18-25 years old) in the southwestern U.S.; (2) characterize the impact of chronic environmental stress exposure on regulatory mechanisms of the ANS; and (3) identify socially- and culturally-specific risk and resilience factors associated with physiological stress reactivity in this population. Methods: Participants (N = 277) were assessed across three different time points over a period of four-months. They completed measures of self-reported chronic and race-related stress exposure, behavioral and emotional coping styles, and past 90-day marijuana and alcohol use. They also underwent a laboratory-based stressor to derive measures of autonomic reactivity to acute stress, including heart rate (HR), heart rate variability (HRV), and skin conductance levels (SCL). Results: Higher SCL reactivity to acute stress was associated with higher rates of subsequent alcohol and marijuana use at 90-day follow-up. There was no significant association between autonomic reactivity and chronic, nor race-related stress exposure. However, there was a significant interaction effect, such that active coping moderated the relationship between race-related stress exposure and HRV reactivity to acute stress. Conclusions: These results highlight the role of ANS (dys)regulation as a putative link between environmental stress exposure and subsequent drug use vulnerability among African American emerging adults.Psychological, Health, and Learning Sciences, Department o
Effects of evaluative context in implicit cognitions associated with alcohol and violent behaviors
A large body of literature has substantiated the relationship between alcohol use and violent behaviors, but little consideration has been given to implicit interactions between the two. This study examines the implicit attitudes associated with alcoholic drinks and violent behaviors, and their relationship to explicit reports of problematic behaviors associated with alcohol use. The Go/No-Go Association Task (GNAT, Nosek & Banaji, 2001) was used to test the effect of distracters (noise) on implicit cognitions associated with alcoholic drinks and violent behaviors. Data was collected from 148 students enrolled in a Midwestern university. Irrespective of contextual distractions, participants consistently exhibited negative implicit cognitions associated with violent behaviors. However, context impacted the valence of cognitions associated with alcoholic beverages. Implicit cognitions associated with alcoholic beverages were negative when nonalcoholic beverages were used as distracters, but were positive when licit and illicit drugs were used as distracters. Implicit cognitions associated with alcoholic drinks were correlated with implicit cognitions associated with violent behaviors and explicit measures of problem drinking, problem drug-related behaviors, and measures of craving, to name a few. Evaluative context can have an effect on the expressed appraisal of implicit attitudes. Implications, limitations, and future directions for using the GNAT in addictions research are discussed
Prior Neurosurgery Decreases fMRI Estimates of Language Laterality in Patients with Gliomas within Anterior Language Sites
The impact of previous surgery on the assessment of language dominance with preoperative fMRI remains inconclusive in patients with recurrent brain tumors. Samples in this retrospective study included 17 patients with prior brain surgery and 21 patients without prior surgery (38 patients total; mean age 43.2, SD = 11.9; 18 females; seven left-handed). All the patients were left language dominant, as determined clinically. The two samples were matched on 10 known confounds, including, for example, tumor laterality and location (all tumors affected Brodmann areas 44/45/47). We calculated fMRI language dominance with laterality indices using a whole-brain and region of interest approach (ROI; Broca’s and Wernicke’s area). Patients with prior surgery had decreased fMRI language dominance (p = 0.03) with more activity in the right hemisphere (p = 0.03) than patients without surgery. Patients with prior brain surgery did not display less language activity in the left hemisphere than patients without surgery. These results were replicated using an ROI approach in the affected Broca’s area. Further, we observed no differences between our samples in the unaffected Wernicke’s area. In sum, prior brain surgery affecting Broca’s area could be a confounding factor that needs to be considered when evaluating fMRI language dominance
Tumor location and reduction in functional MRI estimates of language laterality
ObjectiveBrain tumors located close to the language cortex may distort functional MRI (fMRI)-based estimates of language dominance. The nature of this distortion, and whether this is an artifact of numerous confounders, remains unknown. The authors hypothesized tumor bias based on laterality estimates independent of confounders and that the effects are the greatest for tumors proximal to Broca's area.MethodsTo answer this question, the authors reviewed more than 1113 patients who underwent preoperative fMRI to match samples on 11 known confounders (tumor location, size, type, and grade; seizure history; prior neurosurgery; aphasia presence and severity; and patient age, sex, and handedness). The samples included 30 patients with left hemisphere tumors (15 anterior and 15 posterior) and 30 with right hemisphere tumors (15 anterior and 15 posterior), thus totaling 60 patients (25 women; 18 left-handed and 4 ambidextrous; mean age 47 [SD 14.1] years). Importantly, the authors matched not only patients with left and right hemisphere tumors but also those with anterior and posterior tumors. Standard fMRI laterality indices (LIs) were calculated using whole-brain and region of interest (ROI) approaches (Broca's and Wernicke's areas).ResultsTumors close to Broca's area in the left hemisphere decreased LIs independently of known confounders. At the whole-brain level, this appeared to reflect a decrease in LI values in patients with left anterior tumors compared with patients with right anterior tumors. ROI analysis replicated these findings. Broca's area LIs were significantly lower (p = 0.02) in patients with left anterior tumors (mean LI 0.28) when compared with patients with right anterior tumors (mean LI 0.70). Changes in Wernicke's area-based LIs did not differ as a function of the tumor hemisphere. Therefore, in patients with left anterior tumors, it is essential to assess language laterality using left posterior ROIs. In all remaining tumor groups (left posterior tumors and right hemisphere tumors), language laterality derived from the anterior language ROI was the most robust measure of language dominance.ConclusionsPatients with tumors close to Broca's area showed more bilateral fMRI language maps independent of known confounders. The authors caution against the assumption that this reduced language laterality suggests no or little risk to language function following tumor resection in the left inferior frontal gyrus. Their results address how to interpret fMRI data for neurosurgical purposes, along with theoretical questions of contralesional functional compensation and disinhibition
Field-work and geographer training: some contributions for its reflection
Del 15 al 17 de noviembre del 2011, en el Departamento de Geografía de la Facultad de Filosofía y Humanidades de la Universidad Nacional de Córdoba, se llevaron a cabo las I Jornadas “Formación del geógrafo y trabajo de campo. Reflexiones acerca de su abordaje, articulación y reconocimiento curricular en la carrera de grado”. Recuperar esta experiencia, los aportes y reflexiones dadas en el marco de ese espacio, se vuelve el objetivo central de este artículo.From 15 to 17 November 2011, in the Department of Geography at the Facultad de Filosofía y Humanidades de la Universidad Nacional de Córdoba, were held the First Conference “Formación del geógrafo y trabajo de campo. Reflexiones acerca de su abordaje, articulación y reconocimiento curricular en la carrera de grado”.Recapture this experience, contributions and reflections given in that context, becomes the central objective of this article.Fil: Aichino, Gina Lucia. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de Córdoba; ArgentinaFil: Arancibia, Lorena. Universidad Nacional de Córdoba; ArgentinaFil: Astegiano, Natalia. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de Córdoba; ArgentinaFil: Asis, Yamila. Universidad Nacional de Córdoba; ArgentinaFil: Barrera, Emanuel. Universidad Nacional de Córdoba; ArgentinaFil: Cavanagh, Eugenia. Universidad Nacional de Córdoba; ArgentinaFil: Cisterna, Carolina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de Córdoba; ArgentinaFil: González, Diana. Universidad Nacional de Córdoba; ArgentinaFil: Luna, Lucía. Universidad Nacional de Córdoba; ArgentinaFil: Palladino, Lucas. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de Córdoba; ArgentinaFil: Pedrazzani, Carla Eleonora. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de Córdoba; ArgentinaFil: Rodigou, Jeremías. Universidad Nacional de Córdoba; Argentin
Muscle free fatty-acid uptake associates to mechanical efficiency during exercise in humans
Intrinsic factors related to muscle metabolism may explain the differences in mechanical efficiency (ME) during exercise. Therefore, this study aimed to investigate the relationship between muscle metabolism and ME. Totally 17 healthy recreationally active male subjects were recruited and divided into efficient (EF; n=8) and inefficient (IE; n=9) groups, which were matched for age (mean±SD 24±2 vs. 23±2 yrs), BMI (23±1 vs. 23±2 kg m-2), physical acitivity levels (3.4±1.0 vs. 4.1±1.0 sessions/week), and V ̇O2peak (53±3 vs. 52±3 mL kg-1 min-1), respectively, but differed for ME at 45% of VO2peak intensity during submaximal bicycle ergometer test (EF 20.5±3.5 vs. IE 15.4±0.8 %, P < 0.001). Using Positron Emission Tomography, muscle blood flow (BF) and uptakes of oxygen (mVO2), fatty acids (FAU) and glucose (GU) were measured during dynamic submaximal knee-extension exercise. Workload-normalized BF (EF 35±14 vs. IE 34±11 mL 100g-1 min-1, P = 0.896), mVO2 (EF 4.1±1.2 vs. IE 3.9±1.2 mL 100g-1 min-1, P = 0.808), and GU (EF 3.1±1.8 vs. IE 2.6±2.3 μmol 100g-1 min-1, P = 0.641) as well as the delivery of oxygen, glucose, and fatty acids, as well as respiratory quotient were not different between the groups. However, FAU was significantly higher in EF than IE (3.1±1.7 vs. 1.7±0.6 μmol 100g-1 min-1, P < 0.047) and it also correlated with ME (r=0.56, P < 0.024) in the entire study group. EF group also demonstrated higher use of plasma fatty acids than IE, but no differences in use of plasma glucose and intramuscular energy sources were observed between the groups. These findings suggest that the effective use of plasma fatty acids is an important determinant of mechanical efficiency during exercise
Rationale and Design of the National Neuropsychology Network.
Objective.The National Neuropsychology Network (NNN) is a multicenter clinical research initiative funded by the National Institute of Mental Health (NIMH; R01 MH118514) to facilitate neuropsychology's transition to contemporary psychometric assessment methods with resultant improvement in test validation and assessment efficiency.MethodThe NNN includes four clinical research sites (Emory University; Medical College of Wisconsin; University of California, Los Angeles (UCLA); University of Florida) and Pearson Clinical Assessment. Pearson Q-interactive (Q-i) is used for data capture for Pearson published tests; web-based data capture tools programmed by UCLA, which serves as the Coordinating Center, are employed for remaining measures.ResultsNNN is acquiring item-level data from 500-10,000 patients across 47 widely used Neuropsychology (NP) tests and sharing these data via the NIMH Data Archive. Modern psychometric methods (e.g., item response theory) will specify the constructs measured by different tests and determine their positive/negative predictive power regarding diagnostic outcomes and relationships to other clinical, historical, and demographic factors. The Structured History Protocol for NP (SHiP-NP) helps standardize acquisition of relevant history and self-report data.ConclusionsNNN is a proof-of-principle collaboration: by addressing logistical challenges, NNN aims to engage other clinics to create a national and ultimately an international network. The mature NNN will provide mechanisms for data aggregation enabling shared analysis and collaborative research. NNN promises ultimately to enable robust diagnostic inferences about neuropsychological test patterns and to promote the validation of novel adaptive assessment strategies that will be more efficient, more precise, and more sensitive to clinical contexts and individual/cultural differences