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1.
World Neurosurg ; 164: e1103-e1110, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35660481

RESUMO

BACKGROUND: Although stereotactic ablation surgery is known to ameliorate involuntary movement dramatically, little is known regarding alterations in whole-brain networks due to disruption of the deep brain nucleus. To explore changes in the whole-brain network after thalamotomy, we analyzed structural and functional connectivity alterations using resting-state functional magnetic resonance imaging and diffusion tensor imaging in patients with essential tremor who had undergone focused ultrasound (FUS) thalamotomy. METHODS: Seven patients with intractable essential tremors and 7 age-matched healthy controls were enrolled in the study. The tremor score in essential tremor patients was assessed, and resting-state functional magnetic resonance imaging and diffusion tensor imaging were performed before and 3 months after left ventral intermediate nucleus thalamotomy using FUS. RESULTS: There was a significant improvement in the tremor of the right hand after FUS thalamotomy. Seed-based functional connectivity analysis revealed a significant increase in functional connectivity between the left thalamus and the caudal part of the dorsal premotor cortex after FUS thalamotomy. Structural connectivity analysis did not detect statistically significant changes between before and after FUS. There was no correlation between the changes in functional connectivity and tremor score. CONCLUSIONS: Although the number of cases is small, our results show that functional connectivity between the thalamus and the premotor cortex increases after the amelioration of tremors by FUS thalamotomy. The lack of correlation between increased functional connectivity and clinical tremor scores suggests that the observed increase in functional connectivity may be a compensatory change in the secondary sensorimotor changes that occur after thalamotomy.


Assuntos
Tremor Essencial , Tálamo , Imagem de Tensor de Difusão , Tremor Essencial/diagnóstico por imagem , Tremor Essencial/cirurgia , Humanos , Imageamento por Ressonância Magnética/métodos , Córtex Motor , Tálamo/diagnóstico por imagem , Tálamo/cirurgia , Resultado do Tratamento
2.
Neuropathology ; 41(4): 324-331, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34219295

RESUMO

Amyotrophic lateral sclerosis (ALS) is a progressive neurodegenerative disease; transactivation response DNA-binding protein of 43 kDa (TDP-43) and iron accumulation are supposed to play a crucial role in the pathomechanism of the disease. Here, we report an unusual case of a patient with ALS who presented with speech apraxia as an initial symptom and upper motor neuron deficiencies. In the early clinical stages, single-photon emission computed tomography visualized focal hypoperfusion of the right frontal operculum, and magnetic resonance imaging identified a hypointense area along the frontal lobe on T2-weighted images. Neuropathological examination revealed that neuronophagia of Betz cells, gliosis, appearance of phosphorylated TDP-43 (p-TDP-43)-positive glial and neuronal inclusions, and prominent iron accumulation were frequently visible in the precentral gyrus. TDP-43 pathology and focal iron accumulation were also visible in the frontal operculum, but only a mild neuronal loss and a few p-TDP-43-positive neuronal and glial inclusions were found in the hypoglossal nucleus of the medulla oblongata and anterior horn of the spinal cord. Immunoblot analysis revealed an atypical band pattern for ALS. In our case, abnormal TDP-43 and iron accumulation might possibly have caused neurodegeneration of the frontal operculum, in tandem or independently; it might then have spread into the primary motor area. Our results suggest a causative association between TDP-43 and iron accumulation in the pathomechanisms of ALS presenting with upper motor neuron signs.


Assuntos
Esclerose Lateral Amiotrófica , Apraxias , Córtex Motor , Doenças Neurodegenerativas , Esclerose Lateral Amiotrófica/complicações , Apraxias/diagnóstico por imagem , Humanos , Ferro , Neurônios Motores , Fala
3.
Sci Rep ; 11(1): 11472, 2021 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-34075153

RESUMO

In post-stroke patients, a decreased adherence to antiplatelet drugs is a major challenge in the prevention of recurrent stroke. Previously, we reported an antiplatelet vaccine against S100A9 in mice, but the use of Freund's adjuvant and the difference in amino acid sequences in epitopes between mice and humans were problematic for clinical use. Here, we redesigned the S100A9 vaccine for the common sequence in both humans and monkeys and examined its effects in cynomolgus monkeys with Alum adjuvant. First, we assessed several candidate epitopes and selected 102 to 112 amino acids as the suitable epitope, which could produce antibodies. When this peptide vaccine was intradermally injected into 4 cynomolgus monkeys with Alum, the antibody against human S100A9 was successfully produced. Anti-thrombotic effects were shown in two monkeys in a mixture of vaccinated serum and fresh whole blood from another cynomolgus monkey. Additionally, the anti-thrombotic effects were partially inhibited by the epitope peptide, indicating the feasibility of neutralizing anti-thrombotic effects of produced antibodies. Prolongation of bleeding time was not observed in vaccinated monkeys. Although further studies on increasing the effect of vaccine and safety are necessary, this vaccine will be a promising approach to improve adherence to antiplatelet drugs in clinical settings.


Assuntos
Calgranulina B , Fibrinolíticos , Peptídeos , Trombose , Vacinas , Animais , Calgranulina B/química , Calgranulina B/imunologia , Calgranulina B/farmacologia , Fibrinolíticos/imunologia , Fibrinolíticos/farmacologia , Humanos , Macaca fascicularis , Macaca mulatta , Peptídeos/química , Peptídeos/imunologia , Peptídeos/farmacologia , Trombose/imunologia , Trombose/terapia , Vacinas/imunologia , Vacinas/farmacologia
4.
Neurology ; 96(21): e2587-e2598, 2021 05 25.
Artigo em Inglês | MEDLINE | ID: mdl-33879597

RESUMO

OBJECTIVE: To test the hypothesis that supplementary motor area (SMA) facilitation with functional near-infrared spectroscopy-mediated neurofeedback (fNIRS-NFB) augments poststroke gait and balance recovery, we conducted a 2-center, double-blind, randomized controlled trial involving 54 Japanese patients using the 3-meter Timed Up and Go (TUG) test. METHODS: Patients with subcortical stroke-induced mild to moderate gait disturbance more than 12 weeks from onset underwent 6 sessions of SMA neurofeedback facilitation during gait- and balance-related motor imagery using fNIRS-NFB. Participants were randomly allocated to intervention (28 patients) or placebo (sham: 26 patients). In the intervention group, the fNIRS signal contained participants' cortical activation information. The primary outcome was TUG improvement 4 weeks postintervention. RESULTS: The intervention group showed greater improvement in the TUG test (12.84 ± 15.07 seconds, 95% confidence interval 7.00-18.68) than the sham group (5.51 ± 7.64 seconds, 95% confidence interval 2.43-8.60; group difference 7.33 seconds, 95% CI 0.83-13.83; p = 0.028), even after adjusting for covariates (group × time interaction; F 1.23,61.69 = 4.50, p = 0.030, partial η2 = 0.083). Only the intervention group showed significantly increased imagery-related SMA activation and enhancement of resting-state connectivity between SMA and ventrolateral premotor area. Adverse effects associated with fNIRS-mediated neurofeedback intervention were absent. CONCLUSION: SMA facilitation during motor imagery using fNIRS neurofeedback may augment poststroke gait and balance recovery by modulating the SMA and its related network. CLASSIFICATION OF EVIDENCE: This study provides Class III evidence that for patients with gait disturbance from subcortical stroke, SMA neurofeedback facilitation improves TUG time (UMIN000010723 at UMIN-CTR; umin.ac.jp/english/).


Assuntos
Transtornos Neurológicos da Marcha/reabilitação , Neurorretroalimentação/métodos , Equilíbrio Postural/fisiologia , Recuperação de Função Fisiológica/fisiologia , Reabilitação do Acidente Vascular Cerebral/métodos , Adulto , Idoso , Método Duplo-Cego , Feminino , Marcha , Transtornos Neurológicos da Marcha/etiologia , Humanos , Imaginação , Masculino , Pessoa de Meia-Idade , Córtex Motor/fisiopatologia , Espectroscopia de Luz Próxima ao Infravermelho/métodos
5.
Front Hum Neurosci ; 15: 615584, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33776667

RESUMO

Mental imagery of movement is a potentially valuable rehabilitation task, but its therapeutic efficacy may depend on the specific cognitive strategy employed. Individuals use two main strategies to perform the hand mental rotation task (HMRT), which involves determining whether a visual image depicts a left or right hand. One is the motor imagery (MI) strategy, which involves mentally simulating one's own hand movements. In this case, task performance as measured by response time (RT) is subject to a medial-lateral effect wherein the RT is reduced when the fingertips are directed medially, presumably as the actual motion would be easier. The other strategy is to employ visual imagery (VI), which involves mentally rotating the picture and is not subject to this medial-lateral effect. The rehabilitative benefits of the HMRT are thought to depend on the MI strategy (mental practice), so it is essential to examine the effects of individual factors such as age, image perspective (e.g., palm or back of the hand), and innate ability (as indicated by baseline RT) on the strategy adopted. When presented with pictures of the palm, all subjects in the current study used the MI strategy, regardless of age and ability. In contrast, when subjects were presented with pictures of the back of the hand, the VI strategy predominated among the young age group regardless of performance, while the strategy used by middle-age and elderly groups depended on performance ability. In the middle-age and elderly groups, the VI approach predominated in those with high performance skill, whereas the MI strategy predominated among those with low performance skill. Thus, higher-skill middle-aged and elderly individuals may not necessarily form a motion image during the HMRT, potentially limiting rehabilitation efficacy.

6.
Neurosurgery ; 88(4): 751-757, 2021 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-33469648

RESUMO

BACKGROUND: Several feasibility studies and a randomized, controlled, multicenter trial have demonstrated the safety and efficacy of unilateral transcranial magnetic resonance-guided focused ultrasound (FUS) lesioning of the ventral intermediate thalamic nucleus in treating essential tremor. OBJECTIVE: To evaluate the safety and efficacy of FUS thalamotomy in a Japanese patient cohort through a prospective, multicenter, single-arm confirmatory trial. METHODS: A total of 35 patients with disabling refractory essential tremor underwent unilateral FUS thalamotomy and were followed up for 12 post-treatment months. Safety was measured as the incidence and severity of treatment-related adverse events. Efficacy was measured as the tremor severity and quality of life improvements using the Clinical Rating Scale for Tremor and Questionnaire for Essential Tremor. RESULTS: The mean skull density ratio (SDR) was 0.47. There was a significant decrease in the mean postural tremor score of the treated hand from baseline to 12 mo by 56.4% (95% CI: 46.7%-66.1%; P < .001), which was maintained at last follow-up. Quality of life improved by 46.3% (mean overall Questionnaire for Essential Tremor score of 17.4 [95% CI: 12.1-22.7]) and there were no severe adverse events. The most frequent adverse event was gait disturbance and all events resolved. CONCLUSION: Unilateral FUS thalamotomy allowed significant and sustained tremor relief and improved the quality of life with an outstanding safety profile. The observed safety and efficacy of FUS thalamotomy were comparable to those reported in a previous multicenter study with a low SDR, and inclusion of the low SDR group did not affect effectiveness.


Assuntos
Tremor Essencial/diagnóstico por imagem , Tremor Essencial/cirurgia , Ablação por Ultrassom Focalizado de Alta Intensidade/métodos , Tálamo/diagnóstico por imagem , Tálamo/cirurgia , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Coortes , Tremor Essencial/epidemiologia , Feminino , Humanos , Japão/epidemiologia , Imageamento por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Inquéritos e Questionários , Resultado do Tratamento
7.
Neurotherapeutics ; 18(1): 460-473, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33083995

RESUMO

Go-sha-jinki-Gan (GJG) is a traditional Japanese herbal medicine. In clinical practice, GJG is effective against neuropathic pain and hypersensitivity induced by chemotherapy or diabetes. In our previous study using a chronic constriction injury mouse model, we showed that GJG inhibited microglia activation by suppressing the expression of tumor necrosis factor-α (TNF-α) and p38 mitogen-activated protein kinase (p38 MAPK) in the peripheral nervous system. To investigate whether GJG can suppress inflammation in the central nervous system (CNS) in the context of neurological disorders, we examined the effect of GJG on the activation of resident glial cells and on p38-TNF signaling in two mouse models of neurological disorders: the experimental autoimmune encephalomyelitis (EAE) model of multiple sclerosis and the 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) model of Parkinson's disease. GJG administration relieved the severity of clinical EAE symptoms and MPTP-induced inflammation by decreasing the number of microglia and the production of TNF-α in the spinal cord of EAE mice and the substantia nigra of MPTP-treated mice. Accordingly, GJG suppressed the phosphorylation of p38 in glial cells of these two mouse models. We conclude that GJG attenuates inflammation of the CNS by suppressing glial cell activation, followed by a decrease in the production of TNF-α via p38-TNF signaling.


Assuntos
Sistema Nervoso Central/metabolismo , Medicamentos de Ervas Chinesas/uso terapêutico , Encefalomielite Autoimune Experimental/tratamento farmacológico , Doenças Neuroinflamatórias/tratamento farmacológico , Transtornos Parkinsonianos/tratamento farmacológico , Transdução de Sinais/efeitos dos fármacos , Fator de Necrose Tumoral alfa/metabolismo , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo , Animais , Sistema Nervoso Central/efeitos dos fármacos , Feminino , Medicina Herbária/métodos , Camundongos , Camundongos Endogâmicos C57BL , Neuroglia/efeitos dos fármacos , Neuroglia/metabolismo , Medula Espinal/efeitos dos fármacos , Medula Espinal/metabolismo , Substância Negra/efeitos dos fármacos , Substância Negra/metabolismo
9.
Front Hum Neurosci ; 13: 252, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31379545

RESUMO

A hand mental rotation task (HMRT) is a task wherein a person judges whether an image of a rotated hand is of the right or left hand. Two performance strategies are expected to come into play when performing these tasks: a visual imagery (VI) strategy, in which an image is mentally rotated, and a motor imagery (MI) strategy, in which the movement of a person's own hand is simulated. Although elderly people generally take some time to perform these tasks, ability differs greatly between individuals. The present study hypothesizes that there is a relationship between differences in task performance strategy and performance ability, and it compares performance strategy among elderly people divided into groups with a short mental rotation time and a long mental rotation time. In response to images of the palm, both groups displayed a medial-lateral effect in which responses were faster for images where the third finger was rotated toward the midline of the body than images rotated in the opposite direction, and we inferred that an MI strategy was primarily employed. Meanwhile, in response to images of the back of the hand, a medial-lateral effect was also observed in the group with a long mental rotation time and not in the group with the shortest mental rotation time (VI strategy). These results suggest that different strategies for performing HMRT task are used by elderly people with a short mental rotation time and those with a long mental rotation time.

10.
PLoS One ; 14(7): e0220414, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31348807

RESUMO

This study explored gender differences in correct response rates and response times on a task involving left or right arrow selection and another involving the transformation of mental rotation of the hand. We recruited 15 healthy, right-handed men (age 24.5 ± 6.4) and 15 healthy, right-handed women (age 21.3 ± 4.9). For the tasks, we used pictures of left and right arrows and 32 hand pictures (left and right, palm and back) placed in cons (each at 45° from 0° to 315°). Hand and arrow pictures alternated and were shown at random. Participants decided as quickly as possible whether each picture was left or right. To compare the time taken for the transformation of mental rotation of the hand, we subtracted the average arrow response time from that for the left and right hand pictures for each participant. Correct response rates did not differ significantly between men and women or left and right for either arrow or hand pictures. Regardless of gender, the response time was longer for the left arrow picture than right arrow picture. The response time for the hand picture was longest for both men and women for pictures at rotation angles that were most difficult to align with participants' hands. While there was no difference between men's responses for left and right hand pictures, the responses of women were longer for left than right hand pictures and also than those of men. These findings suggest that both men and women mainly perform the hand mental rotation task with implicit motor imagery. On the other hand, the gender difference in performance might be explained by the difference in balance with other strategies, such as visual imagery, and by cognitive, neurophysiological, and morphological differences.


Assuntos
Mãos/fisiologia , Orientação/fisiologia , Tempo de Reação/fisiologia , Caracteres Sexuais , Adolescente , Adulto , Feminino , Lateralidade Funcional/fisiologia , Humanos , Masculino , Desempenho Psicomotor , Rotação , Inquéritos e Questionários , Adulto Jovem
11.
Sci Rep ; 9(1): 10104, 2019 07 12.
Artigo em Inglês | MEDLINE | ID: mdl-31300701

RESUMO

Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disease characterized by the progressive loss of motor neurons, for which there is no effective treatment. Previously, we generated a Caenorhabditis elegans model of ALS, in which the expression of dnc-1, the homologous gene of human dynactin-1, is knocked down (KD) specifically in motor neurons. This dnc-1 KD model showed progressive motor defects together with axonal and neuronal degeneration, as observed in ALS patients. In the present study, we established a behavior-based, automated, and quantitative drug screening system using this dnc-1 KD model together with Multi-Worm Tracker (MWT), and tested whether 38 candidate neuroprotective compounds could improve the mobility of the dnc-1 KD animals. We found that 12 compounds, including riluzole, which is an approved medication for ALS patients, ameliorated the phenotype of the dnc-1 KD animals. Nifedipine, a calcium channel blocker, most robustly ameliorated the motor deficits as well as axonal degeneration of dnc-1 KD animals. Nifedipine also ameliorated the motor defects of other motor neuronal degeneration models of C. elegans, including dnc-1 mutants and human TAR DNA-binding protein of 43 kDa overexpressing worms. Our results indicate that dnc-1 KD in C. elegans is a useful model for the screening of drugs against motor neuron degeneration, and that MWT is a powerful tool for the behavior-based screening of drugs.


Assuntos
Esclerose Lateral Amiotrófica/tratamento farmacológico , Avaliação Pré-Clínica de Medicamentos/métodos , Fármacos Neuroprotetores/farmacologia , Nifedipino/farmacologia , Riluzol/farmacologia , Esclerose Lateral Amiotrófica/patologia , Animais , Caenorhabditis elegans/efeitos dos fármacos , Caenorhabditis elegans/genética , Proteínas de Caenorhabditis elegans/genética , Modelos Animais de Doenças , Complexo Dinactina/genética , Humanos , Neurônios Motores/patologia
12.
Hum Mol Genet ; 27(22): 3974-3985, 2018 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-30137437

RESUMO

Parkinson's disease (PD) is a neurodegenerative disorder characterized by dopaminergic neuron loss. At present, there are no drugs that stop the progression of PD. As with other multifactorial genetic disorders, genome-wide association studies (GWASs) found multiple risk loci for PD, although their clinical significance remains uncertain. Here, we report the identification of candidate drugs for PD by a method using GWAS data and in silico databases. We identified 57 Food and Drug Administration-approved drug families as candidate neuroprotective drugs for PD. Among them, dabrafenib, which is known as a B-Raf kinase inhibitor and is approved for the treatment of malignant melanoma, showed remarkable cytoprotective effects in neurotoxin-treated SH-SY5Y cells and mice. Dabrafenib was found to inhibit apoptosis, and to enhance the phosphorylation of extracellular signal-regulated kinase (ERK), and inhibit the phosphorylation of c-Jun NH2-terminal kinase. Dabrafenib targets B-Raf, and we confirmed a protein-protein interaction between B-Raf and Rit2, which is coded by RIT2, a PD risk gene in Asians and Caucasians. In RIT2-knockout cells, the phosphorylation of ERK was reduced, and dabrafenib treatment improved the ERK phosphorylation. These data indicated that dabrafenib exerts protective effects against neurotoxicity associated with PD. By using animal model, we confirmed the effectiveness of this in silico screening method. Furthermore, our results suggest that this in silico drug screening system is useful in not only neurodegenerative diseases but also other common diseases such as diabetes mellitus and hypertension.


Assuntos
Imidazóis/administração & dosagem , Proteínas Monoméricas de Ligação ao GTP/genética , Fármacos Neuroprotetores/administração & dosagem , Oximas/administração & dosagem , Doença de Parkinson/tratamento farmacológico , Proteínas Proto-Oncogênicas B-raf/genética , Animais , Antineoplásicos/administração & dosagem , Apoptose/efeitos dos fármacos , Simulação por Computador , Citoproteção/efeitos dos fármacos , Bases de Dados de Compostos Químicos , Neurônios Dopaminérgicos/efeitos dos fármacos , Neurônios Dopaminérgicos/patologia , Aprovação de Drogas , Avaliação Pré-Clínica de Medicamentos/métodos , Estudo de Associação Genômica Ampla , Humanos , Proteínas Quinases JNK Ativadas por Mitógeno/genética , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Melanoma/tratamento farmacológico , Camundongos , Proteínas Monoméricas de Ligação ao GTP/antagonistas & inibidores , Doença de Parkinson/genética , Doença de Parkinson/patologia , Fosforilação/efeitos dos fármacos , Mapas de Interação de Proteínas , Inibidores de Proteínas Quinases/administração & dosagem , Proteínas Proto-Oncogênicas B-raf/antagonistas & inibidores
13.
PLoS One ; 13(3): e0193986, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29518148

RESUMO

We previously demonstrated that patients with multiple sclerosis (MS) of high serum Sema4A levels are resistant to IFN-ß therapy. To further elucidate the role of serum Sema4A as a biomarker for therapeutic stratification in MS patients, it is important to clarify the efficacy of other disease-modifying drugs (DMD) in those with high serum Sema4A levels. Thus, in this study we investigated whether fingolimod has beneficial effects on MS patients with high Sema4A levels. We retrospectively analyzed annualized relapse rate (ARR) and Expanded Disability Status Scale (EDSS) change in 56 relapsing-remitting multiple sclerosis (RRMS) patients who had been treated with fingolimod, including those who switched from IFN-ß therapy. The levels of Sema4A in the sera were measured by sandwich ELISA. The implications of Sema4A on the efficacy of fingolimod were investigated by administering recombinant Sema4A-Fc and fingolimod to mice with experimental autoimmune encephalomyelitis (EAE). Retrospective analysis of MS cohort (17 high Sema4A and 39 low Sema4A) demonstrated the effectiveness of fingolimod in those with high serum Sema4A levels, showing reduction of ARR (from 1.21 to 0.12) and EDSS progression (from 0.50 to 0.04). Consistent with this observation, improvement in the disease severity of EAE mice receiving recombinant Sema4A-Fc was also observed after fingolimod treatment. These data suggest that fingolimod could serve as a candidate DMD for managing the disease activity of MS patients with high Sema4A levels.


Assuntos
Antirreumáticos/uso terapêutico , Encefalomielite Autoimune Experimental/tratamento farmacológico , Cloridrato de Fingolimode/uso terapêutico , Esclerose Múltipla Recidivante-Remitente/tratamento farmacológico , Semaforinas/sangue , Adulto , Animais , Biomarcadores , Progressão da Doença , Avaliação de Medicamentos , Avaliação Pré-Clínica de Medicamentos , Resistência a Medicamentos , Substituição de Medicamentos , Encefalomielite Autoimune Experimental/sangue , Feminino , Humanos , Fragmentos Fc das Imunoglobulinas/genética , Imunoglobulina G/genética , Interferon beta/uso terapêutico , Contagem de Linfócitos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Pessoa de Meia-Idade , Esclerose Múltipla Recidivante-Remitente/sangue , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/toxicidade , Estudos Retrospectivos , Semaforinas/genética , Semaforinas/toxicidade , Índice de Gravidade de Doença , Organismos Livres de Patógenos Específicos , Resultado do Tratamento
14.
Neurobiol Aging ; 37: 103-116, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26545632

RESUMO

With increased histone deacetylase (HDAC) activity and histone hypoacetylation being implicated in neurodegeneration, HDAC inhibitors have been reported to have considerable therapeutic potential. Yet, existing inhibitors lack specificity and may show substantial adverse effect. In this study, we identified a novel HDAC1/2 isoform-specific inhibitor, K560, with protective effects against 1-methyl-4-phenylpyridinium (MPP(+))- and/or 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-induced neuronal death in both in vitro and in vivo Parkinson's disease model. K560 attenuated cell death induced by MPP(+) in differentiated SH-SY5Y cells through the sustained expression of an antiapoptotic protein, X-linked inhibitor of apoptosis (XIAP). Inhibition of XIAP expression by locked nucleic acid antisense oligonucleotides abolished the protective effect of K560. Inactivation of mitogen-activated protein kinase cascades, reduced p53 phosphorylation, and down-regulation of p53-upregulated modulator of apoptosis on K560 treatment were also observed. Furthermore, pre- and post-oral administration of K560 to mice prevented MPTP-induced loss of dopaminergic neurons in substantia nigra, suggesting that selective inhibition of HDAC1 and HDAC2 by K560 may pave the way to new strategies for Parkinson's disease treatment.


Assuntos
Benzamidas/uso terapêutico , Dicetopiperazinas/uso terapêutico , Inibidores Enzimáticos/uso terapêutico , Histona Desacetilase 1/antagonistas & inibidores , Histona Desacetilase 2/antagonistas & inibidores , Terapia de Alvo Molecular , Fármacos Neuroprotetores/uso terapêutico , Doença de Parkinson/tratamento farmacológico , Acetilação , Administração Oral , Animais , Benzamidas/administração & dosagem , Benzamidas/farmacologia , Morte Celular/efeitos dos fármacos , Morte Celular/genética , Linhagem Celular Tumoral , Dicetopiperazinas/administração & dosagem , Dicetopiperazinas/farmacologia , Modelos Animais de Doenças , Avaliação Pré-Clínica de Medicamentos , Inibidores Enzimáticos/farmacologia , Expressão Gênica/efeitos dos fármacos , Histona Desacetilase 1/fisiologia , Histona Desacetilase 2/fisiologia , Histonas/metabolismo , Humanos , Isoenzimas , Camundongos , Fármacos Neuroprotetores/farmacologia , Doença de Parkinson/etiologia , Doença de Parkinson/patologia , Proteínas Inibidoras de Apoptose Ligadas ao Cromossomo X/genética , Proteínas Inibidoras de Apoptose Ligadas ao Cromossomo X/metabolismo
15.
PLoS One ; 9(8): e106553, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25170608

RESUMO

Previous studies showed that the amplitude and latency of the auditory offset cortical response depended on the history of the sound, which implicated the involvement of echoic memory in shaping a response. When a brief sound was repeated, the latency of the offset response depended precisely on the frequency of the repeat, indicating that the brain recognized the timing of the offset by using information on the repeat frequency stored in memory. In the present study, we investigated the temporal resolution of sensory storage by measuring auditory offset responses with magnetoencephalography (MEG). The offset of a train of clicks for 1 s elicited a clear magnetic response at approximately 60 ms (Off-P50m). The latency of Off-P50m depended on the inter-stimulus interval (ISI) of the click train, which was the longest at 40 ms (25 Hz) and became shorter with shorter ISIs (2.5∼20 ms). The correlation coefficient r2 for the peak latency and ISI was as high as 0.99, which suggested that sensory storage for the stimulation frequency accurately determined the Off-P50m latency. Statistical analysis revealed that the latency of all pairs, except for that between 200 and 400 Hz, was significantly different, indicating the very high temporal resolution of sensory storage at approximately 5 ms.


Assuntos
Córtex Auditivo/fisiologia , Magnetoencefalografia/métodos , Memória/fisiologia , Estimulação Acústica , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
16.
Rinsho Shinkeigaku ; 53(11): 1405-7, 2013.
Artigo em Japonês | MEDLINE | ID: mdl-24292005

RESUMO

By progression of the disease, motor neurons degenerate in patients with amyotrophic lateral sclerosis (ALS) eventually lose nearly all voluntary muscles in the body. They are awake and aware but cannot move or communicate (locked-in state). Since the function of the brain is preserved, one possible measure to support their communication is to interpret their motor intention by decoding (deciphering) brain signals and present it with external devices. This technology called "brain-machine interface (BMI)" is now close to clinical use in Japan and USA.In our system, we record electrocorticogram (ECoG) obtained with subudural electrodes during their motor imagery, decode it and determine the movement they intended. So far, one patient of ALS with severe paralysis, implanted with this electrodes, successfully operated the PC communication tool only by thinking.


Assuntos
Esclerose Lateral Amiotrófica/psicologia , Esclerose Lateral Amiotrófica/reabilitação , Interfaces Cérebro-Computador , Auxiliares de Comunicação para Pessoas com Deficiência , Comunicação , Neurocirurgia/instrumentação , Neurocirurgia/métodos , Pensamento/fisiologia , Eletrodos Implantados , Eletroencefalografia , Desenho de Equipamento , Humanos
17.
J Alzheimers Dis ; 37(2): 325-33, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23948880

RESUMO

Previous studies have shown a high prevalence of obstructive sleep apnea (OSA) among patients with Alzheimer's disease (AD). However, it is poorly assessed whether chronic intermittent hypoxia (CIH), which is a characteristic of OSA, affects the pathophysiology of AD. We aimed to investigate the direct effect of intermittent hypoxia (IH) in pathophysiology of AD in vivo and in vitro. In vivo, 15 male triple transgenic AD mice were exposed to either CIH or normoxia (5% O2 and 21% O2 every 10 min, 8 h/day for 4 weeks). Amyloid-ß (Aß) profile, cognitive brain function, and brain pathology were evaluated. In vitro, human neuroblastoma SH-SY5Y cells stably expressing wild-type amyloid-ß protein precursor were exposed to either IH (8 cycles of 1% O2 for 10 min followed by 21% O2 for 20 min) or normoxia. The Aß profile in the conditioned medium was analyzed. CIH significantly increased levels of Aß42 but not Aß40 in the brains of mice without the increase in hypoxia-inducible factor 1, alpha subunit (HIF-1α) expression. Furthermore, CIH significantly increased intracellular Aß in the brain cortex. There were no significant changes in cognitive function. IH significantly increased levels of Aß42 in the medium of SH-SY5Y cells without the increase in the HIF-1α expression. CIH directly and selectively increased levels of Aß42 in the AD model. Our results suggest that OSA would aggravate AD. Early detection and intervention of OSA in AD may help to alleviate the progression of the disease.


Assuntos
Doença de Alzheimer/metabolismo , Peptídeos beta-Amiloides/metabolismo , Oxigenoterapia Hiperbárica , Hipóxia/metabolismo , Doença de Alzheimer/complicações , Doença de Alzheimer/genética , Secretases da Proteína Precursora do Amiloide/metabolismo , Precursor de Proteína beta-Amiloide/metabolismo , Animais , Ácido Aspártico Endopeptidases/metabolismo , Linhagem Celular Tumoral , Transtornos Cognitivos/etiologia , Modelos Animais de Doenças , Ensaio de Imunoadsorção Enzimática , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Neuroblastoma/patologia
18.
Pain ; 154(10): 1989-1998, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23769719

RESUMO

The imagery of itch and pain evokes emotional responses and covert motor responses (scratching to itch and withdrawal to pain). This suggests some similarity in cerebral mechanisms. However, itch is more socially contagious than pain, as evidenced by the fact that scratching behaviors can be easily initiated by watching itch-inducing situations, whereas withdrawal is less easily initiated by watching painful situations. Thus, we assumed that the cerebral mechanisms of itch imagery partly differ from those of pain imagery in particular with respect to motor regions. We addressed this issue in 18 healthy subjects using functional magnetic resonance imaging. The subjects were instructed to imagine itch and pain sensations in their own bodies while viewing pictures depicting stimuli associated with these sensations. Itch and pain imagery activated the anterior insular cortex (aIC) and motor-related regions such as supplementary motor area, basal ganglia, thalamus, and cerebellum. Activity in these regions was not significantly different between itch and pain imagery. However, functional connectivity between motor-related regions and the aIC showed marked differences between itch and pain imagery. Connectivity with the aIC was stronger in the primary motor and premotor cortices during pain imagery and stronger in the globus pallidus during itch imagery. These findings indicate that brain regions associated with imagery of itch are the same as those involved in imagery of pain, but their functional networks differ. These differences in brain networks may explain why motor responses to itch are more socially contagious than those related to pain.


Assuntos
Córtex Cerebral/fisiologia , Imaginação/fisiologia , Rede Nervosa/fisiologia , Dor/metabolismo , Dor/psicologia , Prurido/metabolismo , Adulto , Mapeamento Encefálico/métodos , Feminino , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Dor/diagnóstico , Estimulação Luminosa/métodos , Projetos Piloto , Prurido/diagnóstico , Prurido/psicologia , Adulto Jovem
19.
Ophthalmology ; 118(10): 2008-13, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21703690

RESUMO

PURPOSE: The mechanism of cupping reversal seen after lowering intraocular pressure (IOP) in pediatric glaucoma is unknown. Theories include forward movement of the lamina cribrosa or shrinkage of a stretched scleral canal. Our study aimed to quantify changes in optic disc size occurring in children who had undergone glaucoma surgery. DESIGN: Retrospective, single-center, observational case series. PARTICIPANTS: Children undergoing incisional surgery for pediatric glaucoma at the University of California, Davis. METHODS: The electronic charts of all patients with pediatric glaucoma were reviewed for the presence of RetCam digital optic nerve photographs (Clarity Medical Systems, Pleasanton, CA). Cases in which the photographs (baseline and follow-up after surgical intervention) were of sufficient quality were analyzed. The optic disc margin was outlined manually using ImageJ software. Inter-session changes in magnification were accounted for by drawing a control polygon joining 4 or 5 fixed landmarks (e.g., vessel crossings) to include a second larger area containing the optic nerve. The optic disc area (in pixels adjusted with the control polygon) was compared between baseline and follow-up images. MAIN OUTCOME MEASURES: Change in disc area between baseline and follow-up after surgery. RESULTS: We identified 29 eyes for which baseline and follow-up images were available for analysis. Fifteen eyes of 9 children showed clinically obvious cupping reversal. Fourteen eyes of 12 children showed no cupping reversal. Disc area decreased by 6.8% (95% confidence interval [CI], -10.0 to -3.3) in the obvious reversal group and increased by 4.3% (95% CI, +1.0 to +7.6) in the no reversal group after surgery (P < 0.0001; Student t test). Percent change in disc area is correlated to percent change in IOP (r=0.540; P=0.0025) and axial length (r=0.534; P=0.0028). CONCLUSIONS: When cupping reversal is clinically apparent after successful IOP-lowering surgery for congenital glaucoma, the scleral canal shrinks in area. In contrast, when cupping reversal is not observed, the scleral ring continues to enlarge, indicating ongoing stress on the optic nerve. Clinically obvious cupping reversal is less frequently observed in adults after surgery, which may reflect a lower elasticity of the scleral ring in adults compared with children. FINANCIAL DISCLOSURE(S): The author(s) have no proprietary or commercial interest in any materials discussed in this article.


Assuntos
Hidroftalmia/cirurgia , Disco Óptico/patologia , Esclera/patologia , Trabeculectomia , Pré-Escolar , Feminino , Humanos , Hidroftalmia/fisiopatologia , Processamento de Imagem Assistida por Computador , Lactente , Pressão Intraocular/fisiologia , Masculino , Fotografação/instrumentação , Estudos Retrospectivos , Tonometria Ocular
20.
Brain Res ; 1172: 82-92, 2007 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-17825803

RESUMO

Several functional imaging studies have demonstrated the importance of fronto-parietal network in dual-task management. However, neural correlates underlying the difference in intensity of dual-task interference between the same and different response modalities remain unknown. Therefore, we investigated the relationship between brain activity associated with dual-task management and the combinations of response modalities. We used the dual-task requiring bilateral finger responses (DT-same condition) and that requiring finger and oral responses (DT-different condition) to visual and auditory stimuli. The right premotor cortex, precuneus and right posterior parietal cortex were significantly activated in the DT-same condition. The neural activities in the right premotor cortex significantly correlated to the delayed responses in the DT-same condition relative to the single-task conditions, indicating that the right premotor cortex is partly associated with dual-task management (i.e., the regulation of information flow). In addition, neural activity in this brain region was significantly higher in the DT-same condition than in the DT-different condition, suggesting that the difference in intensity between the same and different response modalities is partly associated with difference in the load on the premotor cortex between the DT-same and DT-different conditions. The significant activation of the parietal cortex also differed between the DT-same and DT-different conditions. These results demonstrate that brain activity associated with dual-task management differs depending on the combination of response modalities and that such a difference in brain activity, particularly in the right premotor cortex, might be partly associated with the difference in intensity of dual-task interference between the DT-same and DT-different conditions.


Assuntos
Estimulação Acústica/métodos , Mapeamento Encefálico , Encéfalo/fisiologia , Estimulação Luminosa/métodos , Desempenho Psicomotor/fisiologia , Adulto , Análise de Variância , Encéfalo/anatomia & histologia , Circulação Cerebrovascular/fisiologia , Lateralidade Funcional , Humanos , Masculino , Tomografia por Emissão de Pósitrons , Tempo de Reação/fisiologia , Estatística como Assunto
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