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1.
Brain ; 2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38954651

RESUMO

The ability to initiate volitional action is fundamental to human behaviour. Loss of dopaminergic neurons in Parkinson's disease is associated with impaired action initiation, also termed akinesia. Both dopamine and subthalamic deep brain stimulation (DBS) can alleviate akinesia, but the underlying mechanisms are unknown. An important question is whether dopamine and DBS facilitate de novo build-up of neural dynamics for motor execution or accelerate existing cortical movement initiation signals through shared modulatory circuit effects. Answering these questions can provide the foundation for new closed-loop neurotherapies with adaptive DBS, but the objectification of neural processing delays prior to performance of volitional action remains a significant challenge. To overcome this challenge, we studied readiness potentials and trained brain signal decoders on invasive neurophysiology signals in 25 DBS patients (12 female) with Parkinson's disease during performance of self-initiated movements. Combined sensorimotor cortex electrocorticography (ECoG) and subthalamic local field potential (LFP) recordings were performed OFF therapy (N = 22), ON dopaminergic medication (N = 18) and ON subthalamic deep brain stimulation (N = 8). This allowed us to compare their therapeutic effects on neural latencies between the earliest cortical representation of movement intention as decoded by linear discriminant analysis classifiers and onset of muscle activation recorded with electromyography (EMG). In the hypodopaminergic OFF state, we observed long latencies between motor intention and motor execution for readiness potentials and machine learning classifications. Both, dopamine and DBS significantly shortened these latencies, hinting towards a shared therapeutic mechanism for alleviation of akinesia. To investigate this further, we analysed directional cortico-subthalamic oscillatory communication with multivariate granger causality. Strikingly, we found that both therapies independently shifted cortico-subthalamic oscillatory information flow from antikinetic beta (13-35 Hz) to prokinetic theta (4-10 Hz) rhythms, which was correlated with latencies in motor execution. Our study reveals a shared brain network modulation pattern of dopamine and DBS that may underlie the acceleration of neural dynamics for augmentation of movement initiation in Parkinson's disease. Instead of producing or increasing preparatory brain signals, both therapies modulate oscillatory communication. These insights provide a link between the pathophysiology of akinesia and its' therapeutic alleviation with oscillatory network changes in other non-motor and motor domains, e.g. related to hyperkinesia or effort and reward perception. In the future, our study may inspire the development of clinical brain computer interfaces based on brain signal decoders to provide temporally precise support for action initiation in patients with brain disorders.

2.
Mov Disord ; 38(12): 2185-2196, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37823518

RESUMO

BACKGROUND: Deep brain stimulation (DBS) is an effective treatment option for patients with Parkinson's disease (PD). However, clinical programming remains challenging with segmented electrodes. OBJECTIVE: Using novel sensing-enabled neurostimulators, we investigated local field potentials (LFPs) and their modulation by DBS to assess whether electrophysiological biomarkers may facilitate clinical programming in chronically implanted patients. METHODS: Sixteen patients (31 hemispheres) with PD implanted with segmented electrodes in the subthalamic nucleus and a sensing-enabled neurostimulator were included in this study. Recordings were conducted 3 months after DBS surgery following overnight withdrawal of dopaminergic medication. LFPs were acquired while stimulation was turned OFF and during a monopolar review of both directional and ring contacts. Directional beta power and stimulation-induced beta power suppression were computed. Motor performance, as assessed by a pronation-supination task, clinical programming and electrode placement were correlated to directional beta power and stimulation-induced beta power suppression. RESULTS: Better motor performance was associated with stronger beta power suppression at higher stimulation amplitudes. Across directional contacts, differences in directional beta power and the extent of stimulation-induced beta power suppression predicted motor performance. However, within individual hemispheres, beta power suppression was superior to directional beta power in selecting the contact with the best motor performance. Contacts clinically activated for chronic stimulation were associated with stronger beta power suppression than non-activated contacts. CONCLUSIONS: Our results suggest that stimulation-induced ß power suppression is superior to directional ß power in selecting the clinically most effective contact. In sum, electrophysiological biomarkers may guide programming of directional DBS systems in PD patients. © 2023 The Authors. Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society.


Assuntos
Estimulação Encefálica Profunda , Doença de Parkinson , Núcleo Subtalâmico , Humanos , Doença de Parkinson/terapia , Estimulação Encefálica Profunda/métodos , Ritmo beta/fisiologia , Núcleo Subtalâmico/fisiologia , Biomarcadores
3.
Mov Disord ; 38(4): 692-697, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36718788

RESUMO

BACKGROUND: Subthalamic nucleus (STN) beta (13 - 35 Hz) activity is a biomarker reflecting motor state in Parkinson's disease (PD). Adaptive deep brain stimulation (DBS) aims to use beta activity for therapeutic adjustments, but many aspects of beta activity in real-life situations are unknown. OBJECTIVE: The aim was to investigate Christmas-related influences on beta activity in PD. METHODS: Differences in Christmas Day to nonfestive daily averages in chronic biomarker recordings in 4 PD patients with a sensing-enabled STN DBS implant were retrospectively analyzed. Sweet-spot and whole-brain network connectomic analyses were performed. RESULTS: Beta activity was significantly reduced on Christmas Eve in all patients (4.00-9.00 p.m.: -12.30 ± 10.78%, P = 0.015). A sweet spot in the dorsolateral STN connected recording sites to motor, premotor, and supplementary motor cortices. CONCLUSIONS: We demonstrate that festive events can reduce beta biomarker activity. We conclude that circadian and holiday-related changes should be considered when tailoring adaptive DBS algorithms to patient demands. © 2023 The Authors. Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society.


Assuntos
Estimulação Encefálica Profunda , Córtex Motor , Doença de Parkinson , Núcleo Subtalâmico , Humanos , Doença de Parkinson/terapia , Estudos Retrospectivos , Núcleo Subtalâmico/fisiologia
4.
Sensors (Basel) ; 23(11)2023 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-37299968

RESUMO

Bradykinesia is a cardinal hallmark of Parkinson's disease (PD). Improvement in bradykinesia is an important signature of effective treatment. Finger tapping is commonly used to index bradykinesia, albeit these approaches largely rely on subjective clinical evaluations. Moreover, recently developed automated bradykinesia scoring tools are proprietary and are not suitable for capturing intraday symptom fluctuation. We assessed finger tapping (i.e., Unified Parkinson's Disease Rating Scale (UPDRS) item 3.4) in 37 people with Parkinson's disease (PwP) during routine treatment follow ups and analyzed their 350 sessions of 10-s tapping using index finger accelerometry. Herein, we developed and validated ReTap, an open-source tool for the automated prediction of finger tapping scores. ReTap successfully detected tapping blocks in over 94% of cases and extracted clinically relevant kinematic features per tap. Importantly, based on the kinematic features, ReTap predicted expert-rated UPDRS scores significantly better than chance in a hold out validation sample (n = 102). Moreover, ReTap-predicted UPDRS scores correlated positively with expert ratings in over 70% of the individual subjects in the holdout dataset. ReTap has the potential to provide accessible and reliable finger tapping scores, either in the clinic or at home, and may contribute to open-source and detailed analyses of bradykinesia.


Assuntos
Doença de Parkinson , Humanos , Doença de Parkinson/diagnóstico , Doença de Parkinson/terapia , Hipocinesia/diagnóstico , Dedos , Fenômenos Biomecânicos
5.
Behav Res Methods ; 54(2): 649-662, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-34341962

RESUMO

Timed picture naming is a common psycholinguistic paradigm. In this task, participants are asked to label visually depicted objects or actions. Naming performance can be influenced by several picture and verb characteristics which demands fully characterized normative data. In this study, we provide a first German normative data set of picture and verb characteristics associated with a compilation of 283 freely available action pictures and 600 action verbs including naming latencies from 55 participants. We report standard measures for pictures and verbs such as name agreement indices, visual complexity, word frequency, word length, imageability and age of acquisition. In addition, we include less common parameters, such as orthographic Levenshtein distance, transitivity, reflexivity, morphological complexity, and motor content of the pictures and their associated verbs. We use repeated measures correlations in order to investigate associations between picture and word characteristics and linear mixed effects modeling for the prediction of naming latency. Our analyses reveal comparable results to previous studies in other languages, indicating high construct validity. We found that naming latency varied as a function of entropy of responses, word frequency and motor content of pictures and words. In summary, we provide first German normative data for action pictures and their associated verbs and identify variables influencing naming latency.


Assuntos
Idioma , Nomes , Humanos , Psicolinguística
6.
Forensic Sci Med Pathol ; 18(2): 125-132, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35091897

RESUMO

To explore if the shutdown of Danish nightlife during the Covid-19 pandemic caused a decrease in the number of clinical forensic examinations of victims of sexual assault in Eastern Denmark. Secondarily, to investigate, if there was a change in criminological characteristics, e.g. scene and time of crime, relation to the perpetrator and the proportion of possible drug-facilitated sexual assaults. 130 case files from clinical forensic examinations of individuals of alleged sexual assault in the period 1st of April to 30th of June in both 2019 and 2020 were included. 67 and 63 examinations were performed in 2019 and 2020, respectively. 125 cases were female and five were male. Approximately 70% were 15-25 years of age. Pre- and post-lockdown victim profiles were similar regarding assailant relation, location of crime and time of assault. Voluntary intake of alcohol prior to the assault was registered with 46.3% in 2019 and 62% in 2020. The ratio of possible drug-facilitated sexual assault (DFSA) was approximately 50% each year. The lockdown did not seem to change the overall number of examinations or the demographic and criminological characteristics of the sexual assault victims. No decrease in cases of possible DFSA was found despite the lockdown of nightlife venues.


Assuntos
COVID-19 , Vítimas de Crime , Delitos Sexuais , Controle de Doenças Transmissíveis , Dinamarca/epidemiologia , Feminino , Humanos , Masculino , Pandemias , Estudos Retrospectivos
7.
Int J Legal Med ; 135(4): 1395-1405, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33973092

RESUMO

Cardiac diseases and sudden cardiac death (SCD) are more prevalent in individuals diagnosed with schizophrenia compared to the general population, with especially coronary artery disease (CAD) as the major cardiovascular cause of death. Antipsychotic medications, genetics, and lifestyle factors may contribute to the increased SCD in individuals with schizophrenia. The role of antipsychotic medications and lifestyle factors have been widely investigated, while the genetic predisposition to inherited cardiac diseases in schizophrenia is poorly understood. In this study, we examined 100 genes associated with inherited cardiomyopathies and cardiac channelopathies in 97 deceased individuals diagnosed with schizophrenia for the prevalence of genetic variants associated with SCD. The deceased individuals had various causes of death and were included in the SURVIVE project, a prospective, autopsy-based study of mentally ill individuals in Denmark. This is the first study of multiple inherited cardiac disease-related genes in deceased individuals with diagnosed schizophrenia to shed light on the genetic predisposition to SCD in individuals with schizophrenia. We found no evidence for an overrepresentation of rare variants with high penetrance in inherited cardiac diseases, following the American College of Medical Genetics and Genomics and the Association for Molecular Pathology (ACMG) consensus guidelines. However, we found that the deceased individuals had a statistically significantly increased polygenic burden caused by variants in the investigated heart genes compared to the general population. This indicates that common variants with smaller effects in heart genes may play a role in schizophrenia.


Assuntos
Morte Súbita Cardíaca , Predisposição Genética para Doença , Cardiopatias/complicações , Cardiopatias/genética , Esquizofrenia/complicações , Esquizofrenia/genética , Adulto , Idoso , Dinamarca/epidemiologia , Feminino , Medicina Legal , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Masculino , Pessoa de Meia-Idade , Análise de Sequência de DNA
8.
Arch Virol ; 166(1): 281-285, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33216214

RESUMO

Feline morbillivirus infections have gained increased attention due to repeated reports of their association with urinary tract disease in cats. In the present study, 112 serum samples from free-roaming domestic cats in Chile were tested for antibodies against feline morbillivirus genotypes 1 and 2 (FeMV-1 and FeMV-2) using an indirect immunofluorescence assay. In total, 63% of the animals showed antibodies against one or both FeMV genotypes. Antibodies directed exclusively against FeMV-2 were significantly more prevalent in male cats. The correlation of sex and FeMV-2 infection might give insight into potential routes of transmission. We provide, for the first time, serological data on FeMV in Chile.


Assuntos
Doenças do Gato/imunologia , Doenças do Gato/virologia , Infecções por Morbillivirus/imunologia , Infecções por Morbillivirus/virologia , Morbillivirus/imunologia , Animais , Anticorpos Antivirais/imunologia , Gatos , Chile , Feminino , Genótipo , Masculino , Morbillivirus/genética , Estudos Soroepidemiológicos , Infecções Urinárias/imunologia , Infecções Urinárias/virologia
9.
Stress ; 23(1): 69-76, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31322461

RESUMO

Severe mental illness (SMI) is associated with a reduced life expectancy of up to 20 years. One possible contributor to this fact is dysregulation of the hypothalamus-pituitary-adrenal (HPA)-axis. Looking at the morphology of effector organs, such as the adrenal glands themselves, could reveal insights into organ function and response to possible HPA-dysregulation. This forensic autopsy-based study investigated if there were any morphological changes in adrenal glands between decedents who had previously been submitted to a psychiatric hospital with a diagnosis of schizophrenia (n = 34), bipolar (n = 5), or depressive disorder (n = 20), any other psychiatric diagnosis (n = 36) compared with decedents who had no previous psychiatric admission (n = 40). Length of admissions to psychiatric wards and admission in the 180 days preceding death was included in regression as proxy variables for severity of illness. On the macroscopic level, we found no difference in gland weight or volume. On the microscopic level, we found a 25% increase in cross-sectional area of the zona fasciculata (ZF) in decedents who had a diagnosis of schizophrenia compared with controls (p = 0.033). Other diagnosis groups did not differ from controls. Total admission length was positively correlated with area of the ZF.Lay SummaryPeople with a severe mental disorder may be in a constant state of increased stress, which is harmful. This study looked at the adrenal gland, which produces stress hormones, to see if they were different in deceased persons who had suffered from a severe mental illness. We found that the part of the adrenal gland that produces stress hormones is larger in deceased patients who suffered from schizophrenia, but not other types of psychiatric illnesses, compared to deceased persons with no history of psychiatric illness.


Assuntos
Transtornos Mentais/patologia , Zona Fasciculada/patologia , Adulto , Animais , Autopsia , Peso Corporal , Doença Crônica , Feminino , Humanos , Sistema Hipotálamo-Hipofisário , Masculino , Sistema Hipófise-Suprarrenal , Esquizofrenia/patologia
10.
Int J Legal Med ; 134(3): 1195-1201, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-31270603

RESUMO

Autopsies continue to be the most reliable source of mortality statistics; however, more and more death certificates are based on the post-mortem external examination (PME) alone. Forensic PMEs differ from clinical PMEs, because the forensic pathologist usually has no preceding knowledge of the health of the decedent and must rely on information from authorities in the form of the police report. It is useful at the forensic PME to know whether the decedent suffered from a mental illness; however, it is unknown how valid such a diagnosis is, when based upon information in the police report alone. This study compared tentative diagnoses of schizophrenia from 500 forensic PMEs with a reference database based on the Danish National Patient Registry. We found that 19.3% of schizophrenia cases were missed, and 9.1 % of identified cases were false positives. Overall, 11.4% of all assessments were incorrect. Subgroup analysis showed that marital status as 'single' and the finding of illegal substances at the scene were predictors for both correctly identified and overlooked schizophrenia cases. The most reliable source of information was the decedent's general practitioner, whereas friends and neighbors were the most unreliable. Future studies should be aware of the risk of assigning a wrong diagnosis and use as many sources of information as possible. Taking the decedent's social history and observations about the scene into account may add to the diagnostic accuracy.


Assuntos
Autopsia/normas , Medicina Legal/normas , Polícia , Esquizofrenia/diagnóstico , Adulto , Dinamarca/epidemiologia , Feminino , Humanos , Aplicação da Lei , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Sistema de Registros/estatística & dados numéricos
11.
Int J Legal Med ; 134(1): 135-147, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31773318

RESUMO

Schizophrenia patients have higher mortality rates and lower life expectancy than the general population. However, forensic investigations of their deaths often fail to determine the cause of death, hindering prevention. As schizophrenia is a highly heritable condition and given recent advances in our understanding of the genetics of schizophrenia, it is now possible to investigate how genetic factors may contribute to mortality. We made use of findings from genome-wide association studies (GWAS) to design a targeted panel (PsychPlex) for sequencing of exons of 451 genes near index single nucleotide polymorphisms (SNPs) identified with GWAS. We sequenced the DNA of 95 deceased schizophrenia patients included in SURVIVE, a prospective, autopsy-based study of mentally ill persons in Denmark. We compared the allele frequencies of 1039 SNPs in these cases with the frequencies of 2000 Danes without psychiatric diseases and calculated their deleteriousness (CADD) scores. For 81 SNPs highly associated with schizophrenia and CADD scores above 15, expression profiles in the Genotype-Tissue Expression (GTEx) Project indicated that these variants were in exons, whose expressions are increased in several types of brain tissues, particularly in the cerebellum. Molecular pathway analysis indicated the involvement of 163 different pathways. As for rare SNP variants, most variants were scored as either benign or likely benign with an average of 17 variants of unknown significance per individual and no pathogenic variant. Our results highlight the potential of DNA sequencing of an exon panel to discover genetic factors that may be involved in the development of schizophrenia.


Assuntos
Éxons , Frequência do Gene , Variação Genética , Polimorfismo de Nucleotídeo Único , Esquizofrenia/genética , Análise de Sequência de DNA/métodos , Adulto , Idoso , Causas de Morte , Dinamarca , Feminino , Perfilação da Expressão Gênica , Estudo de Associação Genômica Ampla , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Esquizofrenia/mortalidade
12.
Forensic Sci Med Pathol ; 16(1): 119-122, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31667731

RESUMO

We present an autopsy-validated, non-invasive, magnetic resonance imaging (MRI) based segmentation algorithm, for determining hippocampal volume. A segmentation algorithm was developed to assess the volume of the hippocampus. Deceased individuals with severe mental illness were used to evaluate the use of MRI imaging to determine hippocampal volume as this group has previously been associated with altered hippocampal volume diagnosed on MRI. The accuracy of the MR- scanning protocol for volume measurement was tested on a water filled phantom control with a known volume of 500 ml, and a difference of 0.08% was found. Thus the scanning protocol was deemed to have produced acceptable results when comparing volume measures of a pair of segmented hippocampi obtained at the 1 T MR scanner and a 3 T MR scanner using the software program Mimics®. The segmentation algorithm was tested by a volume comparison obtained using anterior and posterior landmarks (in situ) and the exact volume of the dissected hippocampus (ex situ). The in situ and ex situ hippocampal volumes were highly correlated; R2 was 96%, with a mean difference of 4-5%. Cases were also examined for intra- and inter-observer agreement. This study presents a validated segmentation algorithm that can be used to determine the hippocampal volume using post-mortem MR and anatomical landmarks.


Assuntos
Hipocampo/diagnóstico por imagem , Hipocampo/patologia , Imageamento por Ressonância Magnética , Algoritmos , Pontos de Referência Anatômicos , Autopsia , Humanos , Processamento de Imagem Assistida por Computador , Imageamento Tridimensional , Tomografia Computadorizada por Raios X
13.
Cell Tissue Res ; 373(2): 487-498, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29549435

RESUMO

The morphology and neurophysin expression of the magnocellular accessory neuroendocrine system located in the rostral human hypothalamus is investigated in a series of brains obtained at autopsy. The hypothalami were fixed in formalin and embedded in paraffin, or after cryoprotection, frozen for cryostat sectioning. Paraffin sections were either stained with Luxol Fast blue or immunoreacted for neurophysin I or neurophysin II, the precursor molecule for oxytocin and vasopressin. Further, 50-µm-thick serial cryostat sections were immunoreacted with the same antibodies. Both the paraventricular and supraoptic nuclei as well as the hypothalamo-hypophysial tracts exhibited strong immunoreactivity for the neurophysin antibodies. In addition, large collections of immunoreactive accessory magnocellular nuclei and single scattered neurophysin-positive neurons were located in the preoptic region between the paraventricular and supraoptic nucleus among the hypothalamo-hypophysial nerve fibers. In addition, smaller collections of neurophysin-immunoreactive neurons were located in the basal part of this region. Among the accessory magnocellular nuclei, the classical circular nucleus was identified. Accessory magnocellular neurons were often located along the blood vessels and projections of some of these neurons penetrated the vascular endothelium. The accessory magnocellular cell bodies expressed either neurophysin I or neurophysin II immunoreactivity. Summarizing, the accessory magnocellular system in the human brain is large and differs in morphology compared to the system seen in other vertebrates. The neurons of this system contain both vasopressin and oxytocin. Some neurons of the accessory neuronal systems might secrete vasopressin or oxytocin directly into the blood stream.


Assuntos
Hipotálamo/citologia , Fenômenos Magnéticos , Sistemas Neurossecretores/citologia , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
14.
Forensic Sci Med Pathol ; 11(4): 504-8, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26499953

RESUMO

Reports by minors of sexual relations against their will are not rare, and in some cases pornographic photography is a part of the abuse. Such material can be used to help identify the perpetrator. In this study we examined the efficacy of visual comparison between two databases. One consisted of blinded still images of the back of the right hand of 51 males from video recordings, the other of blinded high quality camera images of the back of the right hand from the same 51 individuals. The images were compared in pairs (2601 combinations) and a judgment was made about whether they were a highly likely, possible or unlikely match, using several anatomical features as markers for comparison. Using this method all 51 high quality images were correctly matched with the video image from the same person, though in some cases there was up to 5 other samples that could not be excluded as possible matches. In total there were no false positive "highly possible" matches, but there were 50 false positive "possible" matches. Visual comparison of the back of the hand is a valuable addition to the burden of evidence in a judicial setting, but should not be used as a standalone method to establish proof of identity. The applicability of the method is dependent on the existence of a database of images; the degree of certainty of the identification is directly correlated to the size of the database.


Assuntos
Identificação Biométrica/métodos , Mãos/anatomia & histologia , Fotografação , Gravação em Vídeo , Algoritmos , Pontos de Referência Anatômicos , Ciências Forenses , Humanos , Masculino
15.
Methods Mol Biol ; 2808: 153-165, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38743369

RESUMO

Domestic cats are the natural host of feline morbilliviruses (FeMV). Although other species can also be infected (such as dogs and opossums), no laboratory animal infection model is established so far. In vitro models for studying the molecular pathogenesis are therefore needed. For this purpose, propagation and titration of FeMV are key techniques. Unlike other morbilliviruses, such as canine distemper virus (CDV) or measles virus (MV), FeMV is a slow growing virus in cell culture and is difficult to titrate using classical plaque techniques. Here we describe methods for the efficient isolation of FeMV from natural sources (e.g., urine), the propagation of viral stocks, and their titration. In addition, we establish the generation of a three-dimensional infection model mimicking the feline tubular epithelium.


Assuntos
Infecções por Morbillivirus , Morbillivirus , Animais , Gatos , Morbillivirus/patogenicidade , Morbillivirus/genética , Morbillivirus/fisiologia , Infecções por Morbillivirus/veterinária , Infecções por Morbillivirus/virologia , Rim/virologia , Rim/citologia , Doenças do Gato/virologia , Células Cultivadas , Cultura de Vírus/métodos , Modelos Animais de Doenças , Cultura Primária de Células/métodos
16.
Brain Stimul ; 17(1): 125-133, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38266773

RESUMO

BACKGROUND: Deep brain stimulation (DBS) is an invasive treatment option for patients with Parkinson's disease. Recently, adaptive DBS (aDBS) systems have been developed, which adjust stimulation timing and amplitude in real-time. However, it is unknown how changes in parameters, movement states and the controllability of subthalamic beta activity affect aDBS performance. OBJECTIVE: To characterize how parameter choice, movement state and controllability interactively affect the electrophysiological and behavioral response to single threshold aDBS. METHODS: We recorded subthalamic local field potentials in 12 patients with Parkinson's disease receiving single threshold aDBS in the acute post-operative state. We investigated changes in two aDBS parameters: the onset time and the smoothing of real-time beta power. Electrophysiological patterns and motor performance were assessed while patients were at rest and during a simple motor task. We further studied the impact of controllability on aDBS performance by comparing patients with and without beta power modulation during continuous stimulation. RESULTS: Our findings reveal that changes in the onset time control the extent of beta power suppression achievable with single threshold adaptive stimulation during rest. Behavioral data indicate that only specific parameter combinations yield a beneficial effect of single threshold aDBS. During movement, action induced beta power suppression reduces the responsivity of the closed loop algorithm. We further demonstrate that controllability of beta power is a prerequisite for effective parameter dependent modulation of subthalamic beta activity. CONCLUSION: Our results highlight the interaction between single threshold aDBS parameter selection, movement state and controllability in driving subthalamic beta activity and motor performance. By this means, we identify directions for the further development of closed-loop DBS algorithms.


Assuntos
Estimulação Encefálica Profunda , Doença de Parkinson , Núcleo Subtalâmico , Humanos , Doença de Parkinson/terapia , Estimulação Encefálica Profunda/métodos , Movimento/fisiologia , Fenômenos Eletrofisiológicos
17.
Lancet Digit Health ; 5(2): e59-e70, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36528541

RESUMO

BACKGROUND: Deep brain stimulation (DBS) of the subthalamic nucleus (STN) is highly effective in controlling motor symptoms in patients with Parkinson's disease. However, correct selection of stimulation parameters is pivotal to treatment success and currently follows a time-consuming and demanding trial-and-error process. We aimed to assess treatment effects of stimulation parameters suggested by a recently published algorithm (StimFit) based on neuroimaging data. METHODS: This double-blind, randomised, crossover, non-inferiority trial was carried out at Charité - Universitätsmedizin, Berlin, Germany, and enrolled patients with Parkinson's disease treated with directional octopolar electrodes targeted at the STN. All patients had undergone DBS programming according to our centre's standard of care (SoC) treatment before study recruitment. Based on perioperative imaging data, DBS electrodes were reconstructed and StimFit was applied to suggest optimal stimulation settings. Patients underwent motor assessments using the Movement Disorder Society-Sponsored Revision of the Unified Parkinson's Disease Rating Scale part III (MDS-UPDRS-III) during OFF-medication and in OFF-stimulation and ON-stimulation states under both conditions, StimFit and SoC parameter settings. Patients were randomly assigned (1:1) to receive either StimFit-programmed DBS first and SoC-programmed DBS second, or SoC-programmed DBS first and StimFit-programmed DBS second. The allocation schedule was generated using a computerised random number generator. Both the rater and patients were masked to the sequence of SoC and StimFit stimulation conditions. All patients who participated in the study were included in the analysis. The primary endpoint of this study was the absolute mean difference between MDS-UPDRS-III scores under StimFit and SoC stimulation, with a non-inferiority margin of 5 points. The study was registered at the German Register for Clinical Trials (DRKS00023115), and is complete. FINDINGS: Between July 10, 2020, and Oct 28, 2021, 35 patients were enrolled in the study; 18 received StimFit followed by SoC stimulation, and 17 received SoC followed by StimFit stimulation. Mean MDS-UPDRS-III scores improved from 47·3 (SD 17·1) at OFF-stimulation baseline to 24·7 (SD 12·4) and 26·3 (SD 12·4) under SoC and StimFit stimulation, respectively. Mean difference between motor scores was -1·6 (SD 7·1; 95% CI -4·0 to 0·9; superiority test psuperiority=0·20; n=35), establishing non-inferiority of StimFit stimulation at a margin of -5 points (non-inferiority test pnon-inferiority=0·0038). In six patients (17%), initial programming of StimFit settings resulted in acute side-effects and amplitudes were reduced until side-effects disappeared. INTERPRETATION: Automated data-driven algorithms can predict stimulation parameters that lead to motor symptom control comparable to SoC treatment. This approach could significantly decrease the time necessary to obtain optimal treatment parameters. FUNDING: Deutsche Forschungsgemeinschaft through NeuroCure Clinical Research Center and TRR 295.


Assuntos
Estimulação Encefálica Profunda , Doença de Parkinson , Núcleo Subtalâmico , Humanos , Doença de Parkinson/tratamento farmacológico , Estimulação Encefálica Profunda/métodos , Estudos Cross-Over , Núcleo Subtalâmico/fisiologia , Núcleo Subtalâmico/cirurgia , Eletrodos
18.
Res Sq ; 2023 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-37790428

RESUMO

Brain computer interfaces (BCI) provide unprecedented spatiotemporal precision that will enable significant expansion in how numerous brain disorders are treated. Decoding dynamic patient states from brain signals with machine learning is required to leverage this precision, but a standardized framework for identifying and advancing novel clinical BCI approaches does not exist. Here, we developed a platform that integrates brain signal decoding with connectomics and demonstrate its utility across 123 hours of invasively recorded brain data from 73 neurosurgical patients treated for movement disorders, depression and epilepsy. First, we introduce connectomics-informed movement decoders that generalize across cohorts with Parkinson's disease and epilepsy from the US, Europe and China. Next, we reveal network targets for emotion decoding in left prefrontal and cingulate circuits in DBS patients with major depression. Finally, we showcase opportunities to improve seizure detection in responsive neurostimulation for epilepsy. Our platform provides rapid, high-accuracy decoding for precision medicine approaches that can dynamically adapt neuromodulation therapies in response to the individual needs of patients.

19.
Forensic Sci Int ; 335: 111283, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35397360

RESUMO

Estimation of the time of death (TOD) is a central task to forensic pathologists. The current gold standard method for TOD-estimation is only applicable in the first 24 h post-mortem and it is advisable to employ multiple methods, if possible. A wristwatch found on the decedent can be a valuable additional tool for TOD-estimation. This technical report provides a brief overview of the two major watch types - mechanical and quartz-based timepieces - and a step-by-step guide to using these for TOD-estimation. The methods are demonstrated using case illustrations.


Assuntos
Joias , Mudanças Depois da Morte , Punho , Humanos , Patologistas
20.
Exp Neurol ; 347: 113869, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34563510

RESUMO

A recent advancement in the field of neuromodulation is to adapt stimulation parameters according to pre-specified biomarkers tracked in real-time. These markers comprise short and transient signal features, such as bursts of elevated band power. To capture these features, instantaneous measures of phase and/or amplitude are employed, which inform stimulation adjustment with high temporal specificity. For adaptive neuromodulation it is therefore necessary to precisely estimate a signal's phase and amplitude with minimum delay and in a causal way, i.e. without depending on future parts of the signal. Here we demonstrate a method that utilizes oscillation theory to estimate phase and amplitude in real-time and compare it to a recently proposed causal modification of the Hilbert transform. By simulating real-time processing of human LFP data, we show that our approach almost perfectly tracks offline phase and amplitude with minimum delay and is computationally highly efficient.


Assuntos
Simulação por Computador , Estimulação Encefálica Profunda/métodos , Doença de Parkinson/terapia , Processamento de Sinais Assistido por Computador , Adulto , Idoso , Encéfalo/fisiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
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