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1.
Neurobiol Dis ; 178: 106012, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36696792

RESUMEN

Tau protein pathology is a hallmark of many neurodegenerative diseases, including Alzheimer's Disease or frontotemporal dementia. Synaptic dysfunction and abnormal visual evoked potentials have been reported in murine models of tauopathy, but little is known about the state of the network activity on a single neuronal level prior to brain atrophy. In the present study, oscillatory rhythms and single-cell calcium activity of primary visual cortex pyramidal neuron population were investigated in basal and light evoked states in the rTg4510 tauopathy mouse model prior to neurodegeneration. We found a decrease in their responsivity and overall activity which was insensitive to GABAergic modulation. Despite an enhancement of basal state coactivation of cortical pyramidal neurons, a loss of input-output synchronicity was observed. Dysfunction of cortical pyramidal function was also reflected in a reduction of basal theta oscillations and enhanced susceptibility to a sub-convulsive dose of pentylenetetrazol in rTg4510 mice. Our results unveil impairments in visual cortical pyramidal neuron processing and define aberrant oscillations as biomarker candidates in early stages of neurodegenerative tauopathies.


Asunto(s)
Enfermedad de Alzheimer , Tauopatías , Ratones , Animales , Potenciales Evocados Visuales , Ratones Transgénicos , Tauopatías/patología , Proteínas tau/genética , Proteínas tau/metabolismo , Neuronas/metabolismo , Enfermedad de Alzheimer/metabolismo , Modelos Animales de Enfermedad
2.
J Neurophysiol ; 127(1): 225-238, 2022 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-34936519

RESUMEN

It has been hypothesized that to perform sensorimotor transformations efficiently, somatosensory information being fed back to a particular motor circuit is organized in accordance with the mechanical loading patterns of the skin that result from the motor activity generated by that circuit. Rearrangements of sensory information to different motor circuits could in this respect constitute a key component of sensorimotor learning. We here explored whether the organization of tactile input from the plantar forepaw of the rat to cortical and striatal circuits is affected by a period of extensive sensorimotor training in a skilled reaching and grasping task. Our data show that the representation of tactile stimuli in terms of both temporal and spatial response patterns changes as a consequence of the training and that spatial changes particularly involve the primary motor cortex. Based on the observed reorganization, we propose that reshaping of the spatiotemporal representation of the tactile afference to motor circuits is an integral component of the learning process that underlies skill acquisition in reaching and grasping.NEW & NOTEWORTHY Sensorimotor transformations are fundamental to the function of the nervous system and determine how patterns of sensory input are converted into appropriate movements. We here investigated the extent to which experience-dependent processes can reshape the organization of somatosensory input feeding into cortico-basal ganglia motor structures. Our data point to a particularly important role for the primary motor cortex in the functional adaptions associated with skilled motor learning.


Asunto(s)
Corteza Cerebral/fisiología , Cuerpo Estriado/fisiología , Actividad Motora/fisiología , Destreza Motora/fisiología , Red Nerviosa/fisiología , Práctica Psicológica , Percepción del Tacto/fisiología , Animales , Conducta Animal/fisiología , Miembro Anterior/fisiología , Corteza Motora/fisiología , Ratas , Percepción Espacial/fisiología , Percepción del Tiempo/fisiología
3.
BMC Psychiatry ; 19(1): 205, 2019 07 03.
Artículo en Inglés | MEDLINE | ID: mdl-31266488

RESUMEN

BACKGROUND: Expert psychiatrists conducting work disability evaluations often disagree on work capacity (WC) when assessing the same patient. More structured and standardised evaluations focusing on function could improve agreement. The RELY studies aimed to establish the inter-rater reproducibility (reliability and agreement) of 'functional evaluations' in patients with mental disorders applying for disability benefits and to compare the effect of limited versus intensive expert training on reproducibility. METHODS: We performed two multi-centre reproducibility studies on standardised functional WC evaluation (RELY 1 and 2). Trained psychiatrists interviewed 30 and 40 patients respectively and determined WC using the Instrument for Functional Assessment in Psychiatry (IFAP). Three psychiatrists per patient estimated WC from videotaped evaluations. We analysed reliability (intraclass correlation coefficients [ICC]) and agreement ('standard error of measurement' [SEM] and proportions of comparisons within prespecified limits) between expert evaluations of WC. Our primary outcome was WC in alternative work (WCalternative.work), 100-0%. Secondary outcomes were WC in last job (WClast.job), 100-0%; patients' perceived fairness of the evaluation, 10-0, higher is better; usefulness to psychiatrists. RESULTS: Inter-rater reliability for WCalternative.work was fair in RELY 1 (ICC 0.43; 95%CI 0.22-0.60) and RELY 2 (ICC 0.44; 0.25-0.59). Agreement was low in both studies, the 'standard error of measurement' for WCalternative.work was 24.6 percentage points (20.9-28.4) and 19.4 (16.9-22.0) respectively. Using a 'maximum acceptable difference' of 25 percentage points WCalternative.work between two experts, 61.6% of comparisons in RELY 1, and 73.6% of comparisons in RELY 2 fell within these limits. Post-hoc secondary analysis for RELY 2 versus RELY 1 showed a significant change in SEMalternative.work (- 5.2 percentage points WCalternative.work [95%CI - 9.7 to - 0.6]), and in the proportions on the differences ≤ 25 percentage points WCalternative.work between two experts (p = 0.008). Patients perceived the functional evaluation as fair (RELY 1: mean 8.0; RELY 2: 9.4), psychiatrists as useful. CONCLUSIONS: Evidence from non-randomised studies suggests that intensive training in functional evaluation may increase agreement on WC between experts, but fell short to reach stakeholders' expectations. It did not alter reliability. Isolated efforts in training psychiatrists may not suffice to reach the expected level of agreement. A societal discussion about achievable goals and readiness to consider procedural changes in WC evaluations may deserve considerations.


Asunto(s)
Trastornos Mentales/diagnóstico , Psiquiatría/métodos , Evaluación de Capacidad de Trabajo , Femenino , Humanos , Masculino , Persona de Mediana Edad , Variaciones Dependientes del Observador , Reproducibilidad de los Resultados
4.
Eur J Neurosci ; 47(3): 236-250, 2018 02.
Artículo en Inglés | MEDLINE | ID: mdl-29250896

RESUMEN

The basal ganglia are thought to be particularly sensitive to changes in dopaminergic tone, and the realization that reduced dopaminergic signaling causes pronounced motor dysfunction is the rationale behind dopamine replacement therapy in Parkinson's disease. It has, however, proven difficult to identify which neurophysiological changes that ultimately lead to motor dysfunctions. To clarify this, we have here recorded neuronal activity throughout the cortico-basal ganglia-thalamic circuits in freely behaving rats during periods of immobility following acute dopaminergic manipulations, involving both vesicular dopamine depletion and antagonism of D1 and D2 type dopamine receptors. Synchronized and rhythmic activities were detected in the form of betaband oscillations in local field potentials and as cortical entrainment of action potentials in several basal ganglia structures. Analyses of the temporal development of synchronized oscillations revealed a spread from cortex to gradually also include deeper structures. In addition, firing rate changes involving neurons in all parts of the network were observed. These changes were typically relatively balanced within each structure, resulting in negligible net rate changes. Animals treated with D1 receptor antagonist showed a rapid onset of hypokinesia that preceded most of the neurophysiological changes, with the exception of these balanced rate changes. Parallel rate changes in functionally coupled ensembles of neurons in different structures may therefore be the first step in a cascade of neurophysiological changes underlying motor symptoms in the parkinsonian state. We suggest that balanced rate changes in distributed networks are possible mechanism of disease that should be further investigated in conditions involving dopaminergic dysfunction.


Asunto(s)
Ganglios Basales/efectos de los fármacos , Ritmo beta/efectos de los fármacos , Dopamina/farmacología , Neuronas/efectos de los fármacos , Potenciales de Acción/efectos de los fármacos , Animales , Ganglios Basales/fisiopatología , Ritmo beta/fisiología , Corteza Cerebral/efectos de los fármacos , Corteza Cerebral/fisiopatología , Femenino , Enfermedad de Parkinson/fisiopatología , Ratas Sprague-Dawley , Receptores de Dopamina D2/efectos de los fármacos
5.
J Occup Rehabil ; 27(2): 268-283, 2017 06.
Artículo en Inglés | MEDLINE | ID: mdl-27393558

RESUMEN

Purpose Unintentional injuries occur frequently and many of the accident survivors suffer from temporary or permanent disabilities. Although most accident victims recover quickly, a significant fraction of them shows a complicated recovery process and accounts for the majority of disability costs. Thus, early identification of vulnerable persons may be beneficial for compensation schemes, government bodies, as well as for the worker themselves. Here we present the Work and Health Questionnaire (WHQ), a screening tool that is already implemented in the case management process of the Swiss Accident Insurance Fund (Suva). Moreover, we demonstrate its prognostic value for identifying workers at risk of a complicated recovery process. Methods A total of 1963 injured workers answered the WHQ within the first 3 months after their accident. All of them had minor to moderate accidental injuries; severely injured workers were excluded from the analyses. The anonymized individual-level data were extracted from insurance databases. We examined construct validity by factorial analyses, and prognostic validity by hierarchical multiple regression analyses on days of work disability. Further, we evaluated well-being and job satisfaction 18 months post-injury in a subsample of 192 injured workers (9.8 %) Results Factor analyses supported five underlying factors (Job Design, Work Support, Job Strain, Somatic Condition/Pain, and Anxiety/Worries). These subscales were moderately correlated, thus indicating that different subscales measured different aspects of work and health-related risk factors of injured workers. Item analysis and reliability analysis showed accurate psychometric properties. Each subscale was predictive at least for one of the evaluated outcomes 18 months post-injury. Conclusion The WHQ shows good psychometric qualities with high clinical utility to identify injured persons with multiple psychosocial risk factors. Thus, the questionnaire appears to be suitable for exploring different rehabilitation needs among minor to moderate injured workers.


Asunto(s)
Evaluación de la Discapacidad , Personas con Discapacidad/estadística & datos numéricos , Traumatismos Ocupacionales/rehabilitación , Indemnización para Trabajadores/economía , Adulto , Bases de Datos Factuales , Personas con Discapacidad/rehabilitación , Femenino , Humanos , Satisfacción en el Trabajo , Modelos Lineales , Masculino , Persona de Mediana Edad , Evaluación de Resultado en la Atención de Salud , Reproducibilidad de los Resultados , Factores de Riesgo , Ausencia por Enfermedad/economía , Ausencia por Enfermedad/estadística & datos numéricos , Indemnización para Trabajadores/estadística & datos numéricos
6.
J Neurophysiol ; 115(3): 1713-29, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-26740532

RESUMEN

Disorders affecting the central nervous system have proven particularly hard to treat, and disappointingly few novel therapies have reached the clinics in recent decades. A better understanding of the physiological processes in the brain underlying various symptoms could therefore greatly improve the rate of progress in this field. We here show how systems-level descriptions of different brain states reliably can be obtained through a newly developed method based on large-scale recordings in distributed neural networks encompassing several different brain structures. Using this technology, we characterize the neurophysiological states associated with parkinsonism and levodopa-induced dyskinesia in a rodent model of Parkinson's disease together with pharmacological interventions aimed at reducing dyskinetic symptoms. Our results show that the obtained electrophysiological data add significant information to conventional behavioral evaluations and hereby elucidate the underlying effects of treatments in greater detail. Taken together, these results potentially open up for studies of neurophysiological mechanisms underlying symptoms in a wide range of neurological and psychiatric conditions that until now have been very hard to investigate in animal models of disease.


Asunto(s)
Antiparkinsonianos/efectos adversos , Ondas Encefálicas/efectos de los fármacos , Evaluación Preclínica de Medicamentos/métodos , Discinesia Inducida por Medicamentos/tratamiento farmacológico , Levodopa/efectos adversos , Animales , Antiparkinsonianos/farmacología , Antiparkinsonianos/uso terapéutico , Modelos Animales de Enfermedad , Neuronas Dopaminérgicas/efectos de los fármacos , Neuronas Dopaminérgicas/fisiología , Discinesia Inducida por Medicamentos/etiología , Discinesia Inducida por Medicamentos/fisiopatología , Electroencefalografía/instrumentación , Electroencefalografía/métodos , Femenino , Ratas , Ratas Sprague-Dawley
7.
BMC Psychiatry ; 16: 271, 2016 07 29.
Artículo en Inglés | MEDLINE | ID: mdl-27474008

RESUMEN

BACKGROUND: Work capacity evaluations by independent medical experts are widely used to inform insurers whether injured or ill workers are capable of engaging in competitive employment. In many countries, evaluation processes lack a clearly structured approach, standardized instruments, and an explicit focus on claimants' functional abilities. Evaluation of subjective complaints, such as mental illness, present additional challenges in the determination of work capacity. We have therefore developed a process for functional evaluation of claimants with mental disorders which complements usual psychiatric evaluation. Here we report the design of a study to measure the reliability of our approach in determining work capacity among patients with mental illness applying for disability benefits. METHODS/DESIGN: We will conduct a multi-center reliability study, in which 20 psychiatrists trained in our functional evaluation process will assess 30 claimants presenting with mental illness for eligibility to receive disability benefits [Reliability of Functional Evaluation in Psychiatry, RELY-study]. The functional evaluation process entails a five-step structured interview and a reporting instrument (Instrument of Functional Assessment in Psychiatry [IFAP]) to document the severity of work-related functional limitations. We will videotape all evaluations which will be viewed by three psychiatrists who will independently rate claimants' functional limitations. Our primary outcome measure is the evaluation of claimant's work capacity as a percentage (0 to 100 %), and our secondary outcomes are the 12 mental functions and 13 functional capacities assessed by the IFAP-instrument. Inter-rater reliability of four psychiatric experts will be explored using multilevel models to estimate the intraclass correlation coefficient (ICC). Additional analyses include subgroups according to mental disorder, the typicality of claimants, and claimant perceived fairness of the assessment process. DISCUSSION: We hypothesize that a structured functional approach will show moderate reliability (ICC ≥ 0.6) of psychiatric evaluation of work capacity. Enrollment of actual claimants with mental disorders referred for evaluation by disability/accident insurers will increase the external validity of our findings. Finding moderate levels of reliability, we will continue with a randomized trial to test the reliability of a structured functional approach versus evaluation-as-usual.


Asunto(s)
Evaluación Médica Independiente , Trastornos Mentales/diagnóstico , Evaluación de Capacidad de Trabajo , Humanos , Seguro por Discapacidad , Psiquiatría , Reproducibilidad de los Resultados , Proyectos de Investigación
8.
PLoS Pathog ; 9(10): e1003640, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-24146614

RESUMEN

Kaposi sarcoma-associated herpesvirus (KSHV) establishes a lifelong latent infection and causes several malignancies in humans. Murine herpesvirus 68 (MHV-68) is a related γ2-herpesvirus frequently used as a model to study the biology of γ-herpesviruses in vivo. The KSHV latency-associated nuclear antigen (kLANA) and the MHV68 mLANA (orf73) protein are required for latent viral replication and persistence. Latent episomal KSHV genomes and kLANA form nuclear microdomains, termed 'LANA speckles', which also contain cellular chromatin proteins, including BRD2 and BRD4, members of the BRD/BET family of chromatin modulators. We solved the X-ray crystal structure of the C-terminal DNA binding domains (CTD) of kLANA and MHV-68 mLANA. While these structures share the overall fold with the EBNA1 protein of Epstein-Barr virus, they differ substantially in their surface characteristics. Opposite to the DNA binding site, both kLANA and mLANA CTD contain a characteristic lysine-rich positively charged surface patch, which appears to be a unique feature of γ2-herpesviral LANA proteins. Importantly, kLANA and mLANA CTD dimers undergo higher order oligomerization. Using NMR spectroscopy we identified a specific binding site for the ET domains of BRD2/4 on kLANA. Functional studies employing multiple kLANA mutants indicate that the oligomerization of native kLANA CTD dimers, the characteristic basic patch and the ET binding site on the kLANA surface are required for the formation of kLANA 'nuclear speckles' and latent replication. Similarly, the basic patch on mLANA contributes to the establishment of MHV-68 latency in spleen cells in vivo. In summary, our data provide a structural basis for the formation of higher order LANA oligomers, which is required for nuclear speckle formation, latent replication and viral persistence.


Asunto(s)
Antígenos Virales/metabolismo , Cromatina/metabolismo , Herpesvirus Humano 8/fisiología , Proteínas Nucleares/metabolismo , Proteínas Serina-Treonina Quinasas/metabolismo , Rhadinovirus/fisiología , Factores de Transcripción/metabolismo , Proteínas Virales/metabolismo , Animales , Antígenos Virales/química , Antígenos Virales/genética , Proteínas de Ciclo Celular , Cromatina/genética , Cromatina/virología , Proteínas Cromosómicas no Histona , Cristalografía por Rayos X , Células HEK293 , Células HeLa , Herpesvirus Humano 8/química , Humanos , Ratones , Proteínas Nucleares/química , Proteínas Nucleares/genética , Multimerización de Proteína , Proteínas Serina-Treonina Quinasas/química , Proteínas Serina-Treonina Quinasas/genética , Estructura Cuaternaria de Proteína , Rhadinovirus/química , Bazo/metabolismo , Bazo/virología , Relación Estructura-Actividad , Factores de Transcripción/química , Factores de Transcripción/genética , Proteínas Virales/química , Proteínas Virales/genética , Latencia del Virus/fisiología
9.
Nature ; 452(7189): 864-7, 2008 Apr 17.
Artículo en Inglés | MEDLINE | ID: mdl-18421351

RESUMEN

Past atmospheric methane concentrations show strong fluctuations in parallel to rapid glacial climate changes in the Northern Hemisphere superimposed on a glacial-interglacial doubling of methane concentrations. The processes driving the observed fluctuations remain uncertain but can be constrained using methane isotopic information from ice cores. Here we present an ice core record of carbon isotopic ratios in methane over the entire last glacial-interglacial transition. Our data show that the carbon in atmospheric methane was isotopically much heavier in cold climate periods. With the help of a box model constrained by the present data and previously published results, we are able to estimate the magnitude of past individual methane emission sources and the atmospheric lifetime of methane. We find that methane emissions due to biomass burning were about 45 Tg methane per year, and that these remained roughly constant throughout the glacial termination. The atmospheric lifetime of methane is reduced during cold climate periods. We also show that boreal wetlands are an important source of methane during warm events, but their methane emissions are essentially shut down during cold climate conditions.


Asunto(s)
Biomasa , Incendios/estadística & datos numéricos , Cubierta de Hielo , Metano/análisis , Metano/química , Temperatura , Árboles/metabolismo , Atmósfera/química , Carbono/análisis , Isótopos de Carbono , Clima Frío , Groenlandia , Historia Antigua , Hidrógeno/análisis , Metano/metabolismo , Método de Montecarlo , Humedales
10.
J Neurosci ; 32(47): 16541-51, 2012 Nov 21.
Artículo en Inglés | MEDLINE | ID: mdl-23175810

RESUMEN

The standard pharmacological treatment for Parkinson's disease using the dopamine precursor levodopa is unfortunately limited by gradual development of disabling involuntary movements for which the underlying causes are poorly understood. Here we show that levodopa-induced dyskinesia in hemiparkinsonian rats is strongly associated with pronounced 80 Hz local field potential oscillations in the primary motor cortex following levodopa treatment. When this oscillation is interrupted by application of a dopamine antagonist onto the cortical surface the dyskinetic symptoms disappear. The finding that abnormal cortical oscillations are a key pathophysiological mechanism calls for a revision of the prevailing hypothesis that links levodopa-induced dyskinesia to an altered sensitivity to dopamine only in the striatum. Apart from having important implications for the treatment of Parkinson's disease, the discovered pathophysiological mechanism may also play a role in several other psychiatric and neurological conditions involving cortical dysfunction.


Asunto(s)
Antiparkinsonianos/toxicidad , Corteza Cerebral/fisiopatología , Discinesia Inducida por Medicamentos/fisiopatología , Electroencefalografía/efectos de los fármacos , Levodopa/toxicidad , Algoritmos , Animales , Corteza Cerebral/efectos de los fármacos , Electrodos Implantados , Potenciales Evocados/efectos de los fármacos , Potenciales Evocados/fisiología , Femenino , Técnica del Anticuerpo Fluorescente , Microelectrodos , Neostriado/efectos de los fármacos , Neostriado/fisiología , Neuronas/clasificación , Oxidopamina , Enfermedad de Parkinson Secundaria/inducido químicamente , Enfermedad de Parkinson Secundaria/fisiopatología , Proteínas Proto-Oncogénicas c-fos/metabolismo , Ratas , Ratas Sprague-Dawley , Receptores de Dopamina D1/metabolismo , Tirosina 3-Monooxigenasa/metabolismo
11.
Rev Neurosci ; 24(4): 415-29, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23907419

RESUMEN

A common observation in recordings of neuronal activity from the cerebral cortex is that populations of neurons show patterns of synchronized oscillatory activity. However, it has been suggested that neuronal synchronization can, in certain pathological conditions, become excessive and possibly have a pathogenic role. In particular, aberrant oscillatory activation patterns have been implicated in conditions involving cortical dysfunction. We here review the mechanisms thought to be involved in the generation of cortical oscillations and discuss their relevance in relation to a recent finding indicating that high-frequency oscillations in the cerebral cortex have an important role in the generation of levodopa-induced dyskinesia. On the basis of these insights, it is suggested that the identification of physiological changes associated with symptoms of disease is a particularly important first step toward a more rapid development of novel treatment strategies.


Asunto(s)
Antiparkinsonianos/efectos adversos , Corteza Cerebral/fisiopatología , Discinesia Inducida por Medicamentos/etiología , Discinesia Inducida por Medicamentos/patología , Levodopa/efectos adversos , Animales , Humanos , Enfermedad de Parkinson/tratamiento farmacológico
12.
J Psychopharmacol ; 37(8): 822-835, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37165655

RESUMEN

BACKGROUND: Understanding the effects of the N-methyl-D-aspartate receptor (NMDA-R) antagonist ketamine on brain function is of considerable interest due to the discovery of its fast-acting antidepressant properties. It is well known that gamma oscillations are increased when ketamine is administered to rodents and humans, and increases in the auditory steady-state response (ASSR) have also been observed. AIMS: To elucidate the cellular substrate of the increase in network activity and synchrony observed by sub-anesthetic doses of ketamine, the aim was to investigate spike timing and regularity and determine how this is affected by the animal's motor state. METHODS: Single unit activity and local field potentials from the auditory cortex of awake, freely moving rats were recorded with microelectrode arrays during an ASSR paradigm. RESULTS: Ketamine administration yielded a significant increase in ASSR power and phase locking, both significantly modulated by motor activity. Before drug administration, putative fast-spiking interneurons (FSIs) were significantly more entrained to the stimulus than putative pyramidal neurons (PYRs). The degree of entrainment significantly increased at lower doses of ketamine (3 and 10 mg/kg for FSIs, 10 mg/kg for PYRs). At the highest dose (30 mg/kg), a strong increase in tonic firing of PYRs was observed. CONCLUSIONS: These findings suggest an involvement of FSIs in the increased network synchrony and provide a possible cellular explanation for the well-documented effects of ketamine-induced increase in power and synchronicity during ASSR. The results support the importance to evaluate different motor states separately for more translational preclinical research.


Asunto(s)
Anestésicos , Corteza Auditiva , Ketamina , Humanos , Ratas , Animales , Ketamina/farmacología , Corteza Auditiva/fisiología , Potenciales Evocados Auditivos , Estimulación Acústica/métodos , Anestésicos/farmacología
13.
Front Psychiatry ; 13: 737295, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35153870

RESUMEN

Ketamine is a non-competitive N-Methyl-D-aspartate receptor (NMDAR) antagonist used in the clinic to initiate and maintain anaesthesia; it induces dissociative states and has emerged as a breakthrough therapy for major depressive disorder. Using local field potential recordings in freely moving rats, we studied resting state EEG profiles induced by co-administering ketamine with either: clozapine, a highly efficacious antipsychotic; or naltrexone, an opioid receptor antagonist reported to block the acute antidepressant effects of ketamine. As human electroencephalography (EEG) is predominantly recorded in a passive state, head-mounted accelerometers were used with rats to determine active and passive states at a high temporal resolution to offer the highest translatability. In general, pharmacological effects for the three drugs were more pronounced in (or restricted to) the passive state. Specifically, during inactive periods clozapine induced increases in delta (0.1-4 Hz), gamma (30-60 Hz) and higher frequencies (>100 Hz). Importantly, it reversed the ketamine-induced reduction in low beta power (10-20 Hz) and potentiated ketamine-induced increases in gamma and high frequency oscillations (130-160 Hz). Naltrexone inhibited frequencies above 50 Hz and significantly reduced the ketamine-induced increase in high frequency oscillations. However, some frequency band changes, such as clozapine-induced decreases in delta power, were only seen in locomoting rats. These results emphasise the potential in differentiating between activity states to capture drug effects and translate to human resting state EEG. Furthermore, the differential reversal of ketamine-induced EEG effects by clozapine and naltrexone may have implications for the understanding of psychotomimetic as well as rapid antidepressant effects of ketamine.

14.
Disabil Rehabil ; 44(20): 6055-6064, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-34343051

RESUMEN

PURPOSE: To investigate the efficacy of a tailored counselling intervention for injured workers regarding different aspects of subjective well-being. MATERIALS AND METHODS: Prospective randomized controlled trial with 192 mildly-to-moderately injured workers who were on sick leave for at least 18 weeks and showed a high-risk profile for a complicated rehabilitation process in a screening. Patients were assessed at baseline, 12 and 18 months post-injury. The outcome variables concerned five aspects of subjective well-being (negative feelings, life and job satisfaction, satisfaction related to family and health). Both the control and the experimental group received conventional case management. Participants in the intervention group additionally received tailored workplace interventions and/or mental health counselling sessions. RESULTS: Participants in the intervention group received an average of 2.23 (SD = 6.94) counselling sessions. Both groups showed a significant reduction (mean (95% CI) of negative feelings control group 2.6 (2.3-3.4), intervention group 2.4 (1.6-3.4)), with a significant difference in negative feelings between the groups (p = 0.01). CONCLUSIONS: Our results suggest that a tailored counselling intervention has a modest long-term effect (d = 0.74) on negative feelings for mildly-to-moderately injured workers. However, future studies should evaluate the feasibility of this study's treatment approach.Implications for rehabilitationAccidents and the resulting injuries often cause a wide range of burdens including psychosocial and emotional distress as well as long-time sick leaves.Tailored counselling led to significant reductions of negative feelings in mildly-to-moderately injured workers over time.By showing that even conventional case management can have a beneficial effect on subjective wellbeing, the results of this study reaffirm the holistic biopsychosocial nature of injury rehabilitation.


Asunto(s)
Consejo , Ausencia por Enfermedad , Humanos , Satisfacción en el Trabajo , Estudios Prospectivos , Lugar de Trabajo
15.
Neuropharmacology ; 158: 107745, 2019 11 01.
Artículo en Inglés | MEDLINE | ID: mdl-31445017

RESUMEN

Non-competitive N-methyl-d-aspartate receptor antagonists mimic schizophrenia symptoms and produce immediate and persistent antidepressant effects. We investigated the effects of ketamine and phencyclidine (PCP) on thalamo-cortical network activity in awake, freely-moving male Wistar rats to gain new insight into the neuronal populations and brain circuits involved in the effects of NMDA-R antagonists. Single unit and local field potential (LFP) recordings were conducted in mediodorsal/centromedial thalamus and in medial prefrontal cortex (mPFC) using microelectrode arrays. Ketamine and PCP moderately increased the discharge rates of principal neurons in both areas while not attenuating the discharge of mPFC GABAergic interneurons. They also strongly affected LFP activity, reducing beta power and increasing that of gamma and high-frequency oscillation bands. These effects were short-lasting following the rapid pharmacokinetic profile of the drugs, and consequently were not present at 24 h after ketamine administration. The temporal profile of both drugs was remarkably different, with ketamine effects peaking earlier than PCP effects. Although this study is compatible with the glutamate hypothesis for fast-acting antidepressant action, it does not support a local disinhibition mechanism as the source for the increased pyramidal neuron activity in mPFC. The short-lasting increase in thalamo-cortical activity is likely associated with the rapid psychotomimetic action of both agents but could also be part of a cascade of events ultimately leading to the persistent antidepressant effects of ketamine. Changes in spectral contents of high-frequency bands by the drugs show potential as translational biomarkers for target engagement of NMDA-R modulators.


Asunto(s)
Potenciales de Acción/efectos de los fármacos , Antagonistas de Aminoácidos Excitadores/farmacología , Neuronas GABAérgicas/efectos de los fármacos , Núcleos Talámicos Intralaminares/efectos de los fármacos , Ketamina/farmacología , Núcleo Talámico Mediodorsal/efectos de los fármacos , Fenciclidina/farmacología , Corteza Prefrontal/efectos de los fármacos , Animales , Neuronas GABAérgicas/metabolismo , Interneuronas/efectos de los fármacos , Interneuronas/metabolismo , Núcleos Talámicos Intralaminares/citología , Núcleos Talámicos Intralaminares/metabolismo , Núcleo Talámico Mediodorsal/citología , Núcleo Talámico Mediodorsal/metabolismo , Neuronas/efectos de los fármacos , Neuronas/metabolismo , Corteza Prefrontal/citología , Corteza Prefrontal/metabolismo , Ratas , Ratas Wistar , Receptores de N-Metil-D-Aspartato/antagonistas & inhibidores , Tálamo , Vigilia
16.
J Electrocardiol ; 41(2): 165-72, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-18328340

RESUMEN

BACKGROUND: The present study investigates spatial properties of atrial fibrillation (AF) by analyzing vectorcardiogram loops synthesized from 12-lead electrocardiograms (ECGs). METHODS: After atrial signal extraction, spatial properties are characterized through analysis of successive, fixed-length signal segments and expressed in loop orientation, that is, azimuth and elevation, as well as in loop morphology, that is, planarity and planar geometry. It is hypothesized that more organized AF, expressed by a lower AF frequency, is associated with decreased variability in loop morphology. Atrial fibrillation frequency is determined using spectral analysis. RESULTS: Twenty-six patients with chronic AF were analyzed using 60-second ECG recordings. Loop orientation was similar when determined from either entire 60- or 1-second segments. For 1-second segments, the correlation between AF frequency and the parameters planarity and planar geometry were 0.608 (P < .001) and 0.543 (P < .005), respectively. CONCLUSIONS: Quantification of AF organization based on AF frequency and spatial characteristics from the ECG is possible. The results suggested a relatively weak coupling between loop morphology and AF frequency when determined from the surface ECG.


Asunto(s)
Algoritmos , Fibrilación Atrial/diagnóstico , Mapeo del Potencial de Superficie Corporal/métodos , Diagnóstico por Computador/métodos , Vectorcardiografía/métodos , Humanos , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
17.
Front Syst Neurosci ; 10: 26, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27065818

RESUMEN

We simultaneously recorded local field potentials (LFPs) in the primary motor cortex and sensorimotor striatum in awake, freely behaving, 6-OHDA lesioned hemi-parkinsonian rats in order to study the features directly related to pathological states such as parkinsonian state and levodopa-induced dyskinesia. We analyzed the spectral characteristics of the obtained signals and observed that during dyskinesia the most prominent feature was a relative power increase in the high gamma frequency range at around 80 Hz, while for the parkinsonian state it was in the beta frequency range. Here we show that during both pathological states effective connectivity in terms of Granger causality is bidirectional with an accent on the striatal influence on the cortex. In the case of dyskinesia, we also found a high increase in effective connectivity at 80 Hz. In order to further understand the 80-Hz phenomenon, we performed cross-frequency analysis and observed characteristic patterns in the case of dyskinesia but not in the case of the parkinsonian state or the control state. We noted a large decrease in the modulation of the amplitude at 80 Hz by the phase of low frequency oscillations (up to ~10 Hz) across both structures in the case of dyskinesia. This may suggest a lack of coupling between the low frequency activity of the recorded network and the group of neurons active at ~80 Hz.

18.
Swiss Med Wkly ; 145: w14160, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26295715

RESUMEN

QUESTIONS: In Switzerland, evaluation of work capacity in individuals with mental disorders has come under criticism. We surveyed stakeholders about their concerns and expectations of the current claim process. METHODS: We conducted a nationwide online survey among five stakeholder groups. We asked 37 questions addressing the claim process and the evaluation of work capacity, the maximum acceptable disagreement in judgments on work capacity, and its documentation. RESULTS: Response rate among 704 stakeholders (95 plaintiff lawyers, 285 treating psychiatrists, 129 expert psychiatrists evaluating work capacity, 64 social judges, 131 insurers) varied between 71% and 29%. Of the lawyers, 92% were dissatisfied with the current claim process, as were psychiatrists (73%) and experts (64%), whereas the majority of judges (72%) and insurers (81%) were satisfied. Stakeholders agreed in their concerns, such as the lack of a transparent relationship between the experts' findings and their conclusions regarding work capacity, medical evaluations inappropriately addressing legal issues, and the experts' delay in finalising the report. Findings mirror the characteristics that stakeholders consider important for an optimal work capacity evaluation. For a scenario where two experts evaluate the same claimant, stakeholders considered an inter-rater difference of 10%‒20% in work capacity at maximum acceptable. CONCLUSIONS: Plaintiff lawyers, treating psychiatrists and experts perceive major problems in work capacity evaluation of psychiatric claims whereas judges and insurers see the process more positively. Efforts to improve the process should include clarifying the basis on which judgments are made, restricting judgments to areas of expertise, and ensuring prompt submission of evaluations.


Asunto(s)
Actitud , Determinación de la Elegibilidad/normas , Seguro por Discapacidad/normas , Trastornos Mentales/diagnóstico , Evaluación de Capacidad de Trabajo , Adulto , Femenino , Humanos , Masculino , Persona de Mediana Edad , Encuestas y Cuestionarios , Suiza
19.
Gene Expr Patterns ; 4(2): 199-204, 2004 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-15161100

RESUMEN

Ezrin is a member of the ERM- (Ezrin-Radixin-Moesin-) family of actin binding proteins, which function as linkers of the cortical cytoskeleton to components of the plasma membrane. Additional roles for Ezrin in intracellular signalling and ion channel regulation were suggested. We found Ezrin mRNA in the anterior endo- and mesoderm of chick gastrula stage embryos. In these tissues Ezrin message is strongly expressed throughout early development of the foregut (pharynx) and heart tube. During later stages of development, highly restricted expression domains of Ezrin mRNA were detected in the endodermal lining of the pharyngeal pouches, the mesonephric duct and tubuli, and in the ectodermal placodes giving rise to the inner ear, eye lens and olfactory epithelium.


Asunto(s)
Epitelio/metabolismo , Expresión Génica/fisiología , Fosfoproteínas/genética , Fosfoproteínas/metabolismo , Animales , Embrión de Pollo , Proteínas del Citoesqueleto , Ectodermo/metabolismo , Endodermo/metabolismo , Ganglios Espinales/metabolismo , Perfilación de la Expresión Génica , Mesodermo/metabolismo
20.
Suicide Life Threat Behav ; 33(2): 192-200, 2003.
Artículo en Inglés | MEDLINE | ID: mdl-12882420

RESUMEN

In the course of a large epidemiological study in the region of Basle, Switzerland, from 1992 to 1996, a considerable rise in suicides assisted by the right-to-die society EXIT was uncovered after wide press coverage of an assisted double suicide of a prominent couple in that region in March 1995. Further investigation revealed that the rise of assisted suicides for a period of 2 years after the critical event was statistically significant compared to the 2 years previous to the double suicide. This was especially true for women older than 65 years. Hence, the almost enthusiastic kind of reporting about this event was apt to induce imitation suicides or a "Werther-effect."


Asunto(s)
Conducta Imitativa , Periódicos como Asunto , Derecho a Morir , Sociedades , Suicidio Asistido/tendencias , Anciano , Estudios Transversales , Femenino , Humanos , Incidencia , Masculino , Suicidio Asistido/psicología , Suicidio Asistido/estadística & datos numéricos , Suiza/epidemiología
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