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1.
BMC Psychiatry ; 23(1): 771, 2023 10 23.
Artigo em Inglês | MEDLINE | ID: mdl-37872497

RESUMO

BACKGROUND: The role of inflammation in the aetiology of schizophrenia has gained wide attention and research on the association shows an exponential growth in the last 15 years. Autoimmune diseases and severe infections are risk factors for the later development of schizophrenia, elevated inflammatory markers in childhood or adolescence are associated with a greater risk of schizophrenia in adulthood, individuals with schizophrenia have increased levels of pro-inflammatory cytokines compared to healthy controls, and autoimmune diseases are overrepresented in schizophrenia. However, treatments with anti-inflammatory agents are so far of doubtful clinical relevance. The primary objective of this study is to test whether the monoclonal antibody rituximab, directed against the B-cell antigen CD20 ameliorates psychotic symptoms in adults with schizophrenia or schizoaffective disorder and to examine potential mechanisms. A secondary objective is to examine characteristics of inflammation-associated psychosis and to identify pre-treatment biochemical characteristics of rituximab responders. A third objective is to interview a subset of patients and informants on their experiences of the trial to obtain insights that rating scales may not capture. METHODS: A proof-of-concept study employing a randomised, parallel-group, double-blind, placebo-controlled design testing the effect of B-cell depletion in patients with psychosis. 120 participants with a diagnosis of schizophrenia spectrum disorders (SSD) (ICD-10 codes F20, F25) will receive either one intravenous infusion of rituximab (1000 mg) or saline. Psychiatric measures and blood samples will be collected at baseline, week 12, and week 24 post-infusion. Brief assessments will also be made in weeks 2 and 7. Neuroimaging and lumbar puncture, both optional, will be performed at baseline and endpoints. Approximately 40 of the patients and their informants will be interviewed for qualitative analyses on the perceived changes in well-being and emotional qualities, in addition to their views on the research. DISCUSSION: This is the first RCT investigating add-on treatment with rituximab in unselected SSD patients. If the treatment is helpful, it may transform the treatment of patients with psychotic disorders. It may also heighten the awareness of immune-psychiatric disorders and reduce stigma. TRIAL REGISTRATION: NCT05622201, EudraCT-nr 2022-000220-37 version 2.1. registered 14th of October 2022.


Assuntos
Doenças Autoimunes , Transtornos Psicóticos , Adulto , Humanos , Método Duplo-Cego , Inflamação , Transtornos Psicóticos/tratamento farmacológico , Ensaios Clínicos Controlados Aleatórios como Assunto , Rituximab/uso terapêutico , Resultado do Tratamento
2.
Neuroimage ; 225: 117500, 2021 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-33169699

RESUMO

BACKGROUND: Regular physical activity is beneficial for cognitive performance in older age. A single bout of aerobic physical exercise can transiently improve cognitive performance. Researchers have advanced improvements in cerebral circulation as a mediator of long-term effects of aerobic physical exercise on cognition, but the immediate effects of exercise on cognition and cerebral perfusion are not well characterized and the effects in older adults are largely unknown. METHODS: Forty-nine older adults were randomized to a 30-min aerobic exercise at moderate intensity or relaxation. Groups were matched on age and cardiovascular fitness (VO2 max). Average Grey Matter Blood Flow (GMBF), measured by a pulsed arterial-spin labeling (pASL) magnetic resonance imaging (MRI) acquisition, and working memory performance, measured by figurative n-back tasks with increasing loads were assessed before and 7 min after exercising/resting. RESULTS: Accuracy on the n-back task increased from before to after exercising/resting regardless of the type of activity. GMBF decreased after exercise, relative to the control (resting) group. In the exercise group, higher n-back performance after exercise was associated with lower GMBF in the right hippocampus, left medial frontal cortex and right orbitofrontal cortex, and higher cardiovascular fitness was associated with lower GMBF. CONCLUSION: The decrease of GMBF reported in younger adults shortly after exercise also occurs in older adults and relates to cardiovascular fitness, potentially supporting the link between cardiovascular fitness and cerebrovascular reactivity in older age.


Assuntos
Encéfalo/diagnóstico por imagem , Circulação Cerebrovascular/fisiologia , Cognição/fisiologia , Exercício Físico/fisiologia , Memória de Curto Prazo , Idoso , Aptidão Cardiorrespiratória , Feminino , Neuroimagem Funcional , Humanos , Imageamento por Ressonância Magnética , Masculino , Imagem de Perfusão
3.
Hum Brain Mapp ; 42(7): 2292-2304, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33635603

RESUMO

Genetic and hormonal factors have been suggested to influence human sexual orientation. Previous studied proposed brain differences related to sexual orientation and that these follow cross-sex shifted patterns. However, the neurobiological correlates of sexual orientation and how genetic factors relate to brain structural variation remains largely unexplored. Using the largest neuroimaging-genetics dataset available on same-sex sexual behavior (SSB) (n = 18,645), we employed a data-driven multivariate classification algorithm (PLS) on magnetic resonance imaging data from two imaging modalities to extract brain covariance patterns related to sex. Through analyses of latent variables, we tested for SSB-related cross-sex shifts in such patterns. Using genotype data, polygenic scores reflecting the genetic predisposition for SSB were computed and tested for associations with neuroimaging outcomes. Patterns important for classifying between males and females were less pronounced in non-heterosexuals. Predominantly in non-heterosexual females, multivariate brain patterns as represented by latent variables were shifted toward the opposite sex. Complementary univariate analyses revealed region specific SSB-related differences in both males and females. Polygenic scores for SSB were associated with volume of lateral occipital and temporo-occipital cortices. The present large-scale study demonstrates multivariate neuroanatomical correlates of SSB, and tentatively suggests that genetic factors related to SSB may contribute to structural variation in certain brain structures. These findings support a neurobiological basis to the differences in human sexuality.


Assuntos
Encéfalo/anatomia & histologia , Homossexualidade/fisiologia , Herança Multifatorial , Comportamento Sexual/fisiologia , Idoso , Bancos de Espécimes Biológicos , Encéfalo/diagnóstico por imagem , Bases de Dados Factuais , Imagem de Tensor de Difusão , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Reino Unido
4.
Acta Psychiatr Scand ; 143(4): 363-374, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33355922

RESUMO

OBJECTIVE: Pedophilic disorder (PD) is characterized bypersistent, intense sexual attraction to prepubertal children that the individual has acted on, or causes marked distress or interpersonal difficulty. Although prior research suggests that PD has neurodevelopmental underpinnings, the evidence remains sparse. To aid the understanding of etiology and treatment development, we quantified neurobiological and clinical correlates of PD. METHOD: We compared 55 self-referred, help-seeking, non-forensic male patients with DSM-5 PD with 57 age-matched, healthy male controls (HC) on clinical, neuropsychological, and structural brain imaging measures (cortical thickness and surface area, subcortical and white matter volumes). Structural brain measures were related to markers for aberrant neurodevelopment including IQ, and the 2nd to 4th digit ratio (2D:4D). RESULTS: PD was associated with psychiatric disorder comorbidity and ADHD and autism spectrum disorder symptoms. PD patients had lower total IQ than HC. PD individuals exhibited cortical surface area abnormalities in regions belonging to the brain's default mode network and showed abnormal volume of white matter underlying those regions. PD subjects had smaller hippocampi and nuclei accumbens than HC. Findings were not related to history of child-related sexual offending. IQ correlated negatively with global expression of PD-related brain features and 2D:4D correlated with surface area in PD. CONCLUSIONS: In the largest single-center study to date, we delineate psychiatric comorbidity, neurobiological and cognitive correlates of PD. Our morphometric findings, their associations with markers of aberrant neurodevelopment, and psychiatric comorbidities suggest that neurodevelopmental mechanisms are involved in PD. The findings may need consideration in future development of clinical management of PD patients.


Assuntos
Transtorno do Espectro Autista , Substância Branca , Encéfalo/diagnóstico por imagem , Humanos , Imageamento por Ressonância Magnética , Masculino , Substância Branca/diagnóstico por imagem
5.
BMC Neurol ; 19(1): 280, 2019 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-31718583

RESUMO

BACKGROUND: Parkinson's disease (PD) affects many physiological systems essential for balance control. Recent studies suggest that intensive and cognitively demanding physical exercise programs are capable of inducing plastic brain changes in PD. We have developed a highly challenging balance training (the HiBalance) program that emphasizes critical aspects of balance control through progressively introducing more challenging exercises which incorporates dual-tasking. Earlier studies have shown it to be effective in improving balance, gait and dual-tasking. The study design has thereafter been adjusted to link intervention-induced behavioral changes to brain morphology and function. Specifically, in this randomized controlled trial, we will determine the effects of the HiBalance program on balance, gait and cognition and relate this to task-evoked functional MRI (fMRI), as well as brain-derived neurotrophic factor (BDNF) in participants with mild-moderate PD. METHODS: One hundred participants with idiopathic PD, Hoehn & Yahr stage 2 or 3, ≥ 60 years of age, ≥ 21 on Montreal Cognitive Assessment will be recruited in successive waves and randomized into either the HiBalance program or to an active control group (the HiCommunication program, targeting speech and communication). Both interventions will be performed in small groups, twice a week with 1 h sessions for 10 weeks. In addition, a 1 h, once a week, home exercise program will also be performed. A double-blinded design will be used. At the pre- and post-assessments, participants will be assessed on balance (main outcome), gait, cognitive functions, physical activity, voice/speech function, BDNF in serum and fMRI (3 T Philips) during performance of motor-cognitive tasks. DISCUSSION: Since there is currently no cure for PD, findings of neuroplastic brain changes in response to exercise would revolutionize the way we treat PD, and, in turn, provide new hope to patients for a life with better health, greater independence and improved quality of life. TRIAL REGISTRATION: ClincalTrials.gov: NCT03213873, first posted July 11, 2017.


Assuntos
Terapia por Exercício/métodos , Plasticidade Neuronal , Doença de Parkinson/reabilitação , Projetos de Pesquisa , Idoso , Encéfalo/fisiopatologia , Método Duplo-Cego , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Doença de Parkinson/fisiopatologia , Equilíbrio Postural/fisiologia , Qualidade de Vida
6.
J Cogn Neurosci ; 30(7): 1033-1046, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29561235

RESUMO

Researchers have proposed that solving complex reasoning problems, a key indicator of fluid intelligence, involves the same cognitive processes as solving working memory tasks. This proposal is supported by an overlap of the functional brain activations associated with the two types of tasks and by high correlations between interindividual differences in performance. We replicated these findings in 53 older participants but also showed that solving reasoning and working memory problems benefits from different configurations of the functional connectome and that this dissimilarity increases with a higher difficulty load. Specifically, superior performance in a typical working memory paradigm ( n-back) was associated with upregulation of modularity (increased between-network segregation), whereas performance in the reasoning task was associated with effective downregulation of modularity. We also showed that working memory training promotes task-invariant increases in modularity. Because superior reasoning performance is associated with downregulation of modular dynamics, training may thus have fostered an inefficient way of solving the reasoning tasks. This could help explain why working memory training does little to promote complex reasoning performance. The study concludes that complex reasoning abilities cannot be reduced to working memory and suggests the need to reconsider the feasibility of using working memory training interventions to attempt to achieve effects that transfer to broader cognition.


Assuntos
Envelhecimento , Encéfalo/fisiologia , Aprendizagem/fisiologia , Memória de Curto Prazo/fisiologia , Modelos Neurológicos , Dinâmica não Linear , Resolução de Problemas/fisiologia , Idoso , Encéfalo/diagnóstico por imagem , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Inteligência , Imageamento por Ressonância Magnética , Masculino , Testes Neuropsicológicos , Oxigênio/sangue
7.
Psychol Sci ; 28(7): 907-920, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28509625

RESUMO

The promise of transcranial direct-current stimulation (tDCS) as a modulator of cognition has appealed to researchers, media, and the general public. Researchers have suggested that tDCS may increase effects of cognitive training. In this study of 123 older adults, we examined the interactive effects of 20 sessions of anodal tDCS over the left prefrontal cortex (vs. sham tDCS) and simultaneous working memory training (vs. control training) on change in cognitive abilities. Stimulation did not modulate gains from pre- to posttest on latent factors of either trained or untrained tasks in a statistically significant manner. A supporting meta-analysis ( n = 266), including younger as well as older individuals, showed that, when combined with training, tDCS was not much more effective than sham tDCS at changing working memory performance ( g = 0.07, 95% confidence interval, or CI = [-0.21, 0.34]) and global cognition performance ( g = -0.01, 95% CI = [-0.29, 0.26]) assessed in the absence of stimulation. These results question the general usefulness of current tDCS protocols for enhancing the effects of cognitive training on cognitive ability.


Assuntos
Cognição/fisiologia , Terapia Cognitivo-Comportamental/instrumentação , Aprendizagem/fisiologia , Memória de Curto Prazo/fisiologia , Córtex Pré-Frontal/fisiologia , Estimulação Transcraniana por Corrente Contínua/métodos , Transferência de Experiência/fisiologia , Idoso , Feminino , Humanos , Masculino , Testes Neuropsicológicos , Resultado do Tratamento
8.
Phys Chem Chem Phys ; 18(27): 18342-52, 2016 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-27334549

RESUMO

The interweave of competing individual relaxations influenced by the presence of temperature and concentration dependent correlations is an intrinsic feature of superparamagnetic nanoparticle suspensions. This unique combination gives rise to multiple applications of such suspensions in medicine, nanotechnology and microfluidics. Here, using theory and experiment, we investigate dynamic magnetic susceptibility in a broad range of temperatures and frequencies. Our approach allows, for the first time to our knowledge, to separate clearly the effects of superparamagnetic particle polydispersity and interparticle magnetic interactions on the dynamic spectra of these systems. In this way, we not only provide a theoretical model that can predict well the dynamic response of magnetic nanoparticles systems, but also deepen the understanding of the dynamic nanoparticle self-assembly, opening new perspectives in tuning and controlling the magnetic behaviour of such systems in AC fields.

9.
Hum Brain Mapp ; 36(8): 3137-53, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26010878

RESUMO

Ego-disturbances have been a topic in schizophrenia research since the earliest clinical descriptions of the disorder. Manifesting as a feeling that one's "self," "ego," or "I" is disintegrating or that the border between one's self and the external world is dissolving, "ego-disintegration" or "dissolution" is also an important feature of the psychedelic experience, such as is produced by psilocybin (a compound found in "magic mushrooms"). Fifteen healthy subjects took part in this placebo-controlled study. Twelve-minute functional MRI scans were acquired on two occasions: subjects received an intravenous infusion of saline on one occasion (placebo) and 2 mg psilocybin on the other. Twenty-two visual analogue scale ratings were completed soon after scanning and the first principal component of these, dominated by items referring to "ego-dissolution", was used as a primary measure of interest in subsequent analyses. Employing methods of connectivity analysis and graph theory, an association was found between psilocybin-induced ego-dissolution and decreased functional connectivity between the medial temporal lobe and high-level cortical regions. Ego-dissolution was also associated with a "disintegration" of the salience network and reduced interhemispheric communication. Addressing baseline brain dynamics as a predictor of drug-response, individuals with lower diversity of executive network nodes were more likely to experience ego-dissolution under psilocybin. These results implicate MTL-cortical decoupling, decreased salience network integrity, and reduced inter-hemispheric communication in psilocybin-induced ego disturbance and suggest that the maintenance of "self"or "ego," as a perceptual phenomenon, may rest on the normal functioning of these systems.


Assuntos
Encéfalo/efeitos dos fármacos , Encéfalo/fisiologia , Alucinógenos/farmacologia , Percepção/efeitos dos fármacos , Percepção/fisiologia , Psilocibina/farmacologia , Adulto , Mapeamento Encefálico , Ego , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Vias Neurais/efeitos dos fármacos , Vias Neurais/fisiologia , Análise de Componente Principal , Autoimagem
10.
Hum Brain Mapp ; 36(8): 2980-95, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25950288

RESUMO

The aim of this study was to assess whether mild cognitive impairment (MCI) is associated with disruption in large-scale structural networks in newly diagnosed, drug-naïve patients with Parkinson's disease (PD). Graph theoretical analyses were applied to 3T MRI data from 123 PD patients and 56 controls from the Parkinson's progression markers initiative (PPMI). Thirty-three patients were classified as having Parkinson's disease with mild cognitive impairment (PD-MCI) using the Movement Disorders Society Task Force criteria, while the remaining 90 PD patients were classified as cognitively normal (PD-CN). Global measures (clustering coefficient, characteristic path length, global efficiency, small-worldness) and regional measures (regional clustering coefficient, regional efficiency, hubs) were assessed in the structural networks that were constructed based on cortical thickness and subcortical volume data. PD-MCI patients showed a marked reduction in the average correlation strength between cortical and subcortical regions compared with controls. These patients had a larger characteristic path length and reduced global efficiency in addition to a lower regional efficiency in frontal and parietal regions compared with PD-CN patients and controls. A reorganization of the highly connected regions in the network was observed in both groups of patients. This study shows that the earliest stages of cognitive decline in PD are associated with a disruption in the large-scale coordination of the brain network and with a decrease of the efficiency of parallel information processing. These changes are likely to signal further cognitive decline and provide support to the role of aberrant network topology in cognitive impairment in patients with early PD.


Assuntos
Encéfalo/patologia , Encéfalo/fisiopatologia , Disfunção Cognitiva/patologia , Disfunção Cognitiva/fisiopatologia , Doença de Parkinson/patologia , Doença de Parkinson/fisiopatologia , Mapeamento Encefálico , Disfunção Cognitiva/etiologia , Progressão da Doença , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Testes Neuropsicológicos , Doença de Parkinson/complicações
11.
Mov Disord ; 29(14): 1802-8, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25284687

RESUMO

Cognitive impairment in Parkinson's disease (PD) is common and does directly impact patients' everyday functioning. However, the underlying mechanisms of early cognitive decline are not known. This study explored the association between striatal dopaminergic deficits and cognitive impairment within a large cohort of early, drug-naïve PD patients and tested the hypothesis that executive dysfunction in PD is associated with striatal dopaminergic depletion. A cross-sectional multicenter cohort of 339 PD patients and 158 healthy controls from the Parkinson's Progression Markers Initiative study was analyzed. Each individual underwent cerebral single-photon emission CT (SPECT) and a standardized neuropsychological assessment with tests of memory as well as visuospatial and executive function. SPECT imaging was performed with [(123) I]FP-CIT, and specific binding ratios in left and right putamen and caudate nucleus were calculated. The association between specific binding ratios, cognitive domain scores, and age was analyzed using Pearson's correlations, partial correlation, and conditional process analysis. A small, but significant, positive association between total striatal dopamine transporter binding and the attention/executive domain was found (r = 0.141; P = 0.009) in PD, but this was not significant after adjusting for age. However, in a moderated mediation model, we found that cognitive executive differences between controls and patients with PD were mediated by an age-moderated striatal dopaminergic deficit. Our findings support the hypothesis that nigrostriatal dopaminergic deficit is associated with executive impairment, but not to memory or visuospatial impairment, in early PD.


Assuntos
Transtornos Cognitivos/diagnóstico , Dopamina/metabolismo , Doença de Parkinson/fisiopatologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Transtornos Cognitivos/metabolismo , Corpo Estriado/metabolismo , Estudos Transversais , Proteínas da Membrana Plasmática de Transporte de Dopamina/metabolismo , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Doença de Parkinson/diagnóstico , Tomografia Computadorizada de Emissão de Fóton Único/métodos , Tropanos
12.
Am J Geriatr Psychiatry ; 22(1): 4-13.e1, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23880336

RESUMO

CONTEXT: Depression is common in dementia, especially in the early stages, with important clinical implications, but the etiology is unknown and most likely heterogeneous. Antidepressant use in the elderly without dementia has previously been shown to be associated with high risks of adverse events and with structural brain alterations. OBJECTIVE: To investigate cortical changes associated with depression and antidepressant use in patients with mild Alzheimer's disease (AD) and Lewy body dementia (LBD). METHODS: 74 subjects with mild AD and LBD from geriatric and psychiatry outpatient clinics in Western Norway were included. The Montgomery-Asberg Depression Rating Scale (MADRS) was used to assess depression. Automatic preprocessing using Freesurfer included steps for white and grey matter surface reconstruction. The resulting cortical thickness was analyzed using linear modeling. RESULTS: Clusters of depression-associated thinning were found in prefrontal and temporal areas. Treatment-associated thinning was observed in the parahippocampal region and was significant even after correction for age, sex, AD/LBD diagnosis, and MADRS scores. CONCLUSION: Depression in mild AD and LBD is associated with cortical thinning in prefrontal and temporal areas. The findings suggest that depressive symptoms in mild dementia could develop due to neurodegeneration in the same neural circuits that are critical for depression across different brain disorders. Antidepressant use in patients with mild AD and LBD is associated with parahippocampal thinning. Taken together with low efficacy of antidepressants in cognitively impaired patients and high risks of adverse events, our results suggest a need to re-evaluate the treatment approaches for depression and the role of antidepressants in patients with dementia.


Assuntos
Doença de Alzheimer/patologia , Antidepressivos/efeitos adversos , Antidepressivos/uso terapêutico , Córtex Cerebral/patologia , Depressão/tratamento farmacológico , Depressão/patologia , Doença por Corpos de Lewy/patologia , Idoso , Doença de Alzheimer/complicações , Doença de Alzheimer/tratamento farmacológico , Atrofia/induzido quimicamente , Atrofia/patologia , Depressão/complicações , Feminino , Humanos , Doença por Corpos de Lewy/complicações , Doença por Corpos de Lewy/tratamento farmacológico , Imageamento por Ressonância Magnética , Masculino , Neuroimagem
13.
J Affect Disord ; 351: 194-201, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38280572

RESUMO

It has long been speculated that psychedelic use could provoke the onset of psychosis, but there is little evidence to support this conjecture. Using a longitudinal research design with samples representative of the US and UK adult populations with regard to sex, age, and ethnicity (n = 9732), we investigated associations between psychedelic use and change in the number of psychotic symptoms during the two-month study period. In covariate-adjusted regression models, psychedelic use during the study period was not associated with a change in the number of psychotic symptoms unless it interacted with a personal or family history of bipolar disorder, in which case the number of symptoms increased, or with a personal (but not family) history of psychotic disorders, in which case the number of symptoms decreased. Taken together, these findings indicate that psychedelic use may affect psychotic symptoms in individuals with a personal or family history of certain disorders characterized by psychotic symptomatology.


Assuntos
Transtorno Bipolar , Alucinógenos , Transtornos Psicóticos , Adulto , Humanos , Estados Unidos/epidemiologia , Alucinógenos/efeitos adversos , Transtornos Psicóticos/tratamento farmacológico , Transtornos Psicóticos/epidemiologia , Transtornos Psicóticos/complicações , Transtorno Bipolar/tratamento farmacológico , Transtorno Bipolar/epidemiologia , Transtorno Bipolar/complicações , Reino Unido/epidemiologia
14.
J Cardiovasc Electrophysiol ; 24(8): 888-93, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23574390

RESUMO

INTRODUCTION: Many patients with atrial fibrillation (AF) receive amiodarone. Amiodarone-induced hyperthyroidism (AIH) may develop as a complication. We hypothesized that pulmonary vein (PV) isolation in patients with paroxysmal AF and history of AIH may yield a lower success rate. METHODS AND RESULTS: Among 704 patients who underwent AF ablation in our center between 2007 and 2010, we identified 20 patients (mean age 58.3 ± 5.0 years; 11 males) with paroxysmal AF and overt AIH in the past. The control group consisted of 40 patients with amiodarone-refractory AF and no thyroid dysfunction. All patients underwent circumferential PV isolation. During redo procedures all tachycardias were targeted for ablation. During a 12-month follow-up, in the AIH group 6 (30%) patients were arrhythmia free after a single procedure, in comparison to 25 (62.5%) controls (P = 0.01). Atrial tachycardia (AT) was registered in 7 (35%) AIH patients and in 1 (2.5%) control patient (P = 0.001). AF recurred in 10 (50%) AIH versus 15 (37.5%) control patients (P = 0.2). Redo ablation was performed in 7 (35%) AIH patients and in 3 (7.5%) non-AIH patients (P = 0.01). During a redo procedure a PV-unrelated tachycardia was diagnosed in 5 (25%) AIH patients (vs 0 in the controls, P = 0.003). After the last performed ablation, 12 (60%) AIH patients and 28 (70%) controls had no recurrence, P = 0.56. AIH was an independent predictor of ATs. CONCLUSION: PV isolation alone has a lower efficacy for preventing recurrence in paroxysmal AF in AIH patients. After repeat ablations, overall freedom from tachyarrhythmias is similar to patients with no history of thyroid dysfunction.


Assuntos
Amiodarona/efeitos adversos , Antiarrítmicos/efeitos adversos , Fibrilação Atrial/tratamento farmacológico , Fibrilação Atrial/cirurgia , Ablação por Cateter/métodos , Hipertireoidismo/induzido quimicamente , Anticoagulantes/uso terapêutico , Estudos de Casos e Controles , Técnicas Eletrofisiológicas Cardíacas , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Modelos de Riscos Proporcionais , Veias Pulmonares/cirurgia , Recidiva , Reoperação , Estatísticas não Paramétricas , Análise de Sobrevida , Resultado do Tratamento
15.
Opt Express ; 21(11): 13617-25, 2013 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-23736614

RESUMO

We experimentally investigate the performance of 60 GHz double sideband (DSB) radio over fiber (RoF) links that employ dispersion compensating fiber (DCF). Error free transmission of 3 Gbps signals over 1 m of wireless distance is reported. In order to overcome experimentally observed chromatic dispersion (CD) induced power fading of radio frequency (RF) signal, we propose a method for improvement of RF carrier-to-noise (C/N) ratio through introduction of a degree of RF frequency tunability. Overall results improve important aspects of directly modulated RoF systems and demonstrate the feasibility of high carrier frequency and wide bandwidth RF signals delivery in RoF links including DCF fiber. Error free performance that we obtain for 3 Gbps amplitude shift-keying (ASK) signals enables uncompressed high-definition 1080p video delivery.

16.
Opt Express ; 21(21): 24574-81, 2013 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-24150301

RESUMO

We present an experimental investigation of the 60 GHz optical carrier suppressed radio over fiber systems with less than 5 dB carrier suppression. As a case study, the 60 GHz RoF signal is generated using a 12.5 Gb/s commercially available Mach-Zehnder modulator biased at its minimum point. We report on error free transmission over 20 km of standard single mode fiber and 1 m of wireless distance. Furthermore, the efficiency of photonic RF generation depending on the value of carrier suppression is reported. We argue that transport of RoF signals with low carrier suppression assisted with simplified techniques of lightwave generation, baseband data modulation, and RF downconversion might be a promising enabling technology for fiber support of close-proximity wireless terminals.

17.
Biosensors (Basel) ; 13(1)2023 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-36671952

RESUMO

The utilizations of microfluidic chips for single RBC (red blood cell) studies have attracted great interests in recent years to filter, trap, analyze, and release single erythrocytes for various applications. Researchers in this field have highlighted the vast potential in developing micro devices for industrial and academia usages, including lab-on-a-chip and organ-on-a-chip systems. This article critically reviews the current state-of-the-art and recent advances of microfluidics for single RBC analyses, including integrated sensors and microfluidic platforms for microscopic/tomographic/spectroscopic single RBC analyses, trapping arrays (including bifurcating channels), dielectrophoretic and agglutination/aggregation studies, as well as clinical implications covering cancer, sepsis, prenatal, and Sickle Cell diseases. Microfluidics based RBC microarrays, sorting/counting and trapping techniques (including acoustic, dielectrophoretic, hydrodynamic, magnetic, and optical techniques) are also reviewed. Lastly, organs on chips, multi-organ chips, and drug discovery involving single RBC are described. The limitations and drawbacks of each technology are addressed and future prospects are discussed.


Assuntos
Anemia Falciforme , Técnicas Analíticas Microfluídicas , Humanos , Microfluídica/métodos , Eritrócitos , Testes Hematológicos , Dispositivos Lab-On-A-Chip
18.
Sci Rep ; 13(1): 16432, 2023 09 30.
Artigo em Inglês | MEDLINE | ID: mdl-37777572

RESUMO

Previous research has suggested that classical psychedelics can foster significant and enduring changes in personality traits and subjective wellbeing. Despite the lack of evidence for adverse effects on mental health stemming from psychedelic use, concerns persist regarding the capacity of these substances to modulate information processing and attitudes towards factual data. The aim of the present study was to investigate the propensity for accepting alternative facts and the general treatment of knowledge within a sample of 392 participants, 233 of whom reported at least a single incidence of psychedelic use in their lifetime. To do this, we leveraged step-wise methods of linear modelling investigating effects of demographics, psychiatric conditions and concomitant drug use. Our findings revealed a moderate positive association between psychedelic use and beliefs in alternative facts, as well as the specific belief that facts are politically influenced. However, no links were found for favouring intuition over evidence when confirming facts. Among other investigated drugs, only alcohol was negatively associated with beliefs in alternative facts. Taken together, our results support the link between psychedelic use and non-conformist thinking styles, which can be attributed to the psychological effects of the drugs themselves, but may also mirror a common trait related to unconventional beliefs and illicit substance use.


Assuntos
Usuários de Drogas , Alucinógenos , Transtornos Relacionados ao Uso de Substâncias , Humanos , Alucinógenos/efeitos adversos , Transtornos Relacionados ao Uso de Substâncias/psicologia , Atitude , Saúde Mental
19.
Materials (Basel) ; 16(16)2023 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-37629919

RESUMO

The quality of graphene intended for use in biosensors was assessed on manufactured chips using a set of methods including atomic force microscopy (AFM), Raman spectroscopy, and low-frequency noise investigation. It is shown that local areas of residues on the graphene surface, formed as a result of the interaction of graphene with a photoresist at the initial stage of chip development, led to a spread of chip resistance (R) in the range of 1-10 kOhm and to an increase in the root mean square (RMS) roughness up to 10 times, which can significantly worsen the reproducibility of the parameters of graphene chips for biosensor applications. It was observed that the control of the photoresist residues after photolithography (PLG) using AFM and subsequent additional cleaning reduced the spread of R values in chips to 1-1.6 kOhm and obtained an RMS roughness similar to the roughness in the graphene film before PLG. Monitoring of the spectral density of low-frequency voltage fluctuation (SU), which provides integral information about the system of defects and quality of the material, makes it possible to identify chips with low graphene quality and with inhomogeneously distributed areas of compressive stresses by the type of frequency dependence SU(f).

20.
Sci Rep ; 12(1): 4646, 2022 03 17.
Artigo em Inglês | MEDLINE | ID: mdl-35301376

RESUMO

The stock market is a bellwether of socio-economic changes that may directly affect individual well-being. Using large-scale UK-biobank data generated over 14 years, we applied specification curve analysis to rigorously identify significant associations between the local stock market index (FTSE100) and 479,791 UK residents' mood, as well as their alcohol intake and blood pressure adjusting the results for a large number of potential confounders, including age, sex, linear and non-linear effects of time, research site, other stock market indexes. Furthermore, we found similar associations between FTSE100 and volumetric measures of affective brain regions in a subsample (n = 39,755; measurements performed over 5.5 years), which were particularly strong around phase transitions characterized by maximum volatility in the market. The main findings did not depend on applied effect-size estimation criteria (linear methods or mutual information criterion) and were replicated in two independent US-based studies (Parkinson's Progression Markers Initiative; n = 424; performed over 2.5 years and MyConnectome; n = 1; 81 measurements over 1.5 years). Our results suggest that phase transitions in the society, indexed by stock market, exhibit close relationships with human mood, health and the affective brain from an individual to population level.


Assuntos
Encéfalo , Investimentos em Saúde , Humanos
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