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1.
J Appl Res Intellect Disabil ; 36(6): 1326-1336, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37620292

RESUMO

BACKGROUND: While epilepsy can decrease quality of life and self-determination in individuals without intellectual disabilities, the impact of epilepsy on experienced self-determination in people with intellectual disabilities remains unclear. METHOD: We conducted semi-structured interviews with six adults (four men, two women) aged 30-61 with mild intellectual disabilities and drug-resistant epilepsy to investigate their experiences of self-determination. The data were analysed using Interpretative Phenomenological Analysis. RESULTS: Three main themes were identified: (A) I am a competent person with epilepsy; (B) My social needs: being accepted as I am and stability in relationships; and (C) Being in control. CONCLUSIONS: In this study, the impact of epilepsy on experienced self-determination of people with mild intellectual disabilities outweighs the influence of intellectual disabilities. Identity formation, friendships with peers, and autonomy support in risk management are identified as important topics in supporting this group.

2.
J Appl Res Intellect Disabil ; 35(2): 506-518, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34761490

RESUMO

BACKGROUND: The reported prevalence of insomnia symptoms in people with intellectual disabilities varies greatly, possibly due to the lack of a common definition. This article provides an overview of the different definitions used and formulates key points for a general definition. METHODS: A literature search was performed. An overview of the definitions used was given and compared to the third edition of the international classification of sleep disorders. RESULTS: The search yielded 16 studies. No uniform definition was used. Terminology and cut-off points of insomnia symptoms differed. Insomnia symptoms were mostly described as night-time problems. A minority of studies incorporated daytime consequences. CONCLUSION: An insomnia disorder entails more than merely night-time complaints and should include daytime consequences. A general definition is warranted. This definition should focus on night-time and daytime insomnia symptoms, incorporate subjective features, and discuss the use of objective measurements and influence of environmental circumstances.


Assuntos
Deficiência Intelectual , Distúrbios do Início e da Manutenção do Sono , Humanos , Deficiência Intelectual/epidemiologia , Prevalência , Distúrbios do Início e da Manutenção do Sono/epidemiologia
3.
J Synchrotron Radiat ; 28(Pt 5): 1662-1668, 2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-34475313

RESUMO

The new Brain Imaging Beamline (BIB) of the Taiwan Photon Source (TPS) has been commissioned and opened to users. The BIB and in particular its endstation are designed to take advantage of bright unmonochromatized synchrotron X-rays and target fast 3D imaging, ∼1 ms exposure time plus very high ∼0.3 µm spatial resolution. A critical step in achieving the planned performances was the solution to the X-ray induced damaging problems of the detection system. High-energy photons were identified as their principal cause and were solved by combining tailored filters/attenuators and a high-energy cut-off mirror. This enabled the tomography acquisition throughput to reach >1 mm3 min-1, a critical performance for large-animal brain mapping and a vital mission of the beamline.


Assuntos
Encéfalo/diagnóstico por imagem , Imageamento Tridimensional , Lesões por Radiação/prevenção & controle , Microtomografia por Raio-X/instrumentação , Animais , Desenho de Equipamento , Fótons , Síncrotrons , Taiwan
4.
BMC Anesthesiol ; 20(1): 69, 2020 03 25.
Artigo em Inglês | MEDLINE | ID: mdl-32213162

RESUMO

BACKGROUND: Chronic osteoarthritic pain is not well understood in terms of its pathophysiological mechanism. Activated glial cells are thought to play a role in the maintenance of chronic pain. T98G glioblastoma cell line was previously observed to release higher amounts of interleukin-6 (IL-6) when treated with cerebrospinal fluid (CSF) from patients with another chronic pain condition, post-herpetic neuralgia. In this study, we investigated the ability of CSF from patients diagnosed with knee osteoarthritis suffering from chronic pain, to trigger the release of pro-inflammatory cytokines, IL-6, IL-1beta and tumour necrosis factor alpha (TNF-α) from T98G. Characterization of upstream signalling was also explored. METHODS: Fifteen osteoarthritis patients undergoing total knee replacement due to chronic knee pain and 15 patients without pain undergoing other surgeries with spinal anaesthesia were prospectively recruited. CSF was collected during anaesthesia. CSF were added to cultured T98G cells in the presence of lipopolysaccharide. IL-6, IL-1ß and TNF-α release from T98G cells were measured using enzyme immunoassay. Antibody array and western blotting were performed using CSF-triggered T98G cell lysates to identify possible signalling targets. Age, gender and pain scores were recorded. Mann-Whitney U test was used to compare IL-6 release and protein expression between groups. Association between IL-6 and pain score was analysed using linear regression. RESULTS: Significant higher levels of IL-6 were released by T98G cells when induced by osteoarthritis patients' CSF in the presence of LPS. The IL-6 levels showed positive association with pain score (adjusted B estimate = 10.1 (95% Confidence Interval 4.3-15.9); p = 0.001). Antibody array conducted with 6 pooled T98G cell lysate induced with osteoarthritis pain patient CSF identified greater than 2-fold proteins including STE20-related kinase adaptor protein and spleen tyrosine kinase. Further validation done using western blotting of individual CSF-triggered T98G cell lysate showed non-significant increase. CONCLUSION: Higher IL-6 release from T98G when triggered by OA-CSF, in the presence of LPS, suggest the presence of "unknown molecule" in CSF that may be crucial in the maintenance phase of chronic pain in our osteoarthritis population. Further studies on the signalling pathways involved in pain and relevance of IL-6 release from T98G cells in other pain models are needed.


Assuntos
Dor Crônica/líquido cefalorraquidiano , Interleucina-6/metabolismo , Neuroglia/metabolismo , Osteoartrite do Joelho/líquido cefalorraquidiano , Artroplastia do Joelho , Linhagem Celular , Células Cultivadas , Feminino , Humanos , Interleucina-1beta/metabolismo , Masculino , Pessoa de Meia-Idade , Osteoartrite do Joelho/cirurgia , Estudos Prospectivos , Fator de Necrose Tumoral alfa/metabolismo
5.
J Biol Chem ; 290(19): 12048-57, 2015 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-25767117

RESUMO

Amyloid precursor protein (APP) is commonly associated with Alzheimer disease, but its physiological function remains unknown. Nav1.6 is a key determinant of neuronal excitability in vivo. Because mouse models of gain of function and loss of function of APP and Nav1.6 share some similar phenotypes, we hypothesized that APP might be a candidate molecule for sodium channel modulation. Here we report that APP colocalized and interacted with Nav1.6 in mouse cortical neurons. Knocking down APP decreased Nav1.6 sodium channel currents and cell surface expression. APP-induced increases in Nav1.6 cell surface expression were Go protein-dependent, enhanced by a constitutively active Go protein mutant, and blocked by a dominant negative Go protein mutant. APP also regulated JNK activity in a Go protein-dependent manner. JNK inhibition attenuated increases in cell surface expression of Nav1.6 sodium channels induced by overexpression of APP. JNK, in turn, phosphorylated APP. Nav1.6 sodium channel surface expression was increased by T668E and decreased by T668A, mutations of APP695 mimicking and preventing Thr-668 phosphorylation, respectively. Phosphorylation of APP695 at Thr-668 enhanced its interaction with Nav1.6. Therefore, we show that APP enhances Nav1.6 sodium channel cell surface expression through a Go-coupled JNK pathway.


Assuntos
Precursor de Proteína beta-Amiloide/metabolismo , Membrana Celular/metabolismo , Canal de Sódio Disparado por Voltagem NAV1.6/metabolismo , Animais , Biotinilação , Córtex Cerebral/metabolismo , Eletrofisiologia , Células HEK293 , Humanos , Imuno-Histoquímica , MAP Quinase Quinase 4/metabolismo , Camundongos , Camundongos Knockout , Camundongos Transgênicos , Microscopia Confocal , Mutação , Doenças Neurodegenerativas/genética , Doenças Neurodegenerativas/metabolismo , Neurônios/metabolismo , Fenótipo , Fosforilação , RNA Interferente Pequeno/metabolismo
6.
Neurochem Res ; 41(1-2): 290-7, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26700428

RESUMO

N-Methyl-D-aspartate receptors are localized to synaptic and extrasynaptic sites of dendritic spines and shafts. Here, the ontogenic profiles of GluN3A and GluN3B subunits in the rat brain were determined. A developmental switch from GluN3A to GluN3B proteins was detected within the first two postnatal weeks of crude synaptosomes prepared from forebrain and midbrain. Further fractionation of crude synaptosomes revealed the preferential localization of GluN3B to synaptic regions from P7 onwards. Immunolabeling and biochemical fractionation of rat P7 cultured hippocampal neurons showed that GluN3B was predominantly at synaptic sites. Unlike GluN2A and GluN2B, both GluN3 subunits were mostly associated with peripheral components of the postsynaptic density (PSD) rather than its core. When considering the non-PSD fraction, the overall extrasynaptic/synaptic spatial profile of GluN3B differed from GluN3A. Heterologous expression of GluN3B with GluN1 in HEK293FT cells could not be co-immunoprecipitated with PSD-95 unless co-expressed with a PSD-95-interacting GluN2 subunit, suggesting that anchoring of GluN3B at synaptic sites may require co-assembly with another scaffold-interacting NMDAR subunit.


Assuntos
Encéfalo/metabolismo , Hipocampo/metabolismo , Neurônios/metabolismo , Receptores de N-Metil-D-Aspartato/metabolismo , Sinapses/metabolismo , Animais , Encéfalo/citologia , Células HEK293 , Hipocampo/citologia , Humanos , Neurônios/citologia , Ratos , Ratos Sprague-Dawley
7.
Epilepsy Behav ; 62: 180-5, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27490905

RESUMO

UNLABELLED: We evaluated the performance of audio-based detection of major seizures (tonic-clonic and long generalized tonic) in adult patients with intellectual disability living in an institute for residential care. METHODS: First, we checked in a random sample (n=17, 102 major seizures) how many patients have recognizable sounds during these seizures. In the second part of this trial, we followed 10 patients (who had major seizures with recognizable sounds) during four weeks with an acoustic monitoring system developed by CLB ('CLB-monitor') and video camera. In week 1, we adapted the sound detection threshold until, per night, a maximum of 20 sounds was found. During weeks 2-4, we selected the epilepsy-related sounds and performed independent video verification and labeling ('snoring', 'laryngeal contraction') of the seizures. The video images were also fully screened for false negatives. In the third part, algorithms in the CLB-monitor detected one specific sound (sleep-related snoring) to illustrate the value of automatic sound recognition. RESULTS: Part 1: recognizable sounds (louder than whispering) occurred in 23 (51%) of the 45 major seizures, 20 seizures (45%) were below this threshold, and 2 (4%) were without any sound. Part 2: in the follow-up group (n=10, 112 major seizures; mean: 11.2, range: 1-30), we found a mean sensitivity of 0.81 (range: 0.33-1.00) and a mean positive predictive value of 0.40 (range: 0.06-1.00). All false positive alarms (mean value: 1.29 per night) were due to minor seizures. We missed 4 seizures (3%) because of lack of sound and 10 (9%) because of sounds below the system threshold. Part 3: the machine-learning algorithms in the CLB-monitor resulted in an overall accuracy for 'snoring' of 98.3%. CONCLUSIONS: Audio detection of major seizures is possible in half of the patients. Lower sound detection thresholds may increase the proportion of suitable candidates. Human selection of seizure-related sounds has a high sensitivity and moderate positive predictive value because of minor seizures which do not need intervention. Algorithms in the CLB-monitor detect seizure-related sounds and may be used alone or in multimodal systems.


Assuntos
Epilepsia/diagnóstico , Deficiência Intelectual/complicações , Monitorização Fisiológica/métodos , Convulsões/diagnóstico , Adolescente , Adulto , Algoritmos , Epilepsia/complicações , Epilepsia/fisiopatologia , Feminino , Humanos , Masculino , Convulsões/complicações , Convulsões/fisiopatologia , Sono , Adulto Jovem
8.
J Clin Gastroenterol ; 49(2): 150-7, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25569223

RESUMO

PURPOSE: Up to 25% of chronic hepatitis B (CHB) patients eventually develop hepatocellular carcinoma (HCC), a disease with poor prognosis unless detected early. This study identifies a blood-based RNA biomarker panel for early HCC detection in CHB. MATERIALS AND METHODS: A genome-wide RNA expression study was performed using RNA extracted from blood samples from Malaysian patients (matched HCC, CHB, controls). Genes differentiating HCC from controls were selected for further testing using quantitative real-time polymerase chain reaction. Finally, a 6-gene biomarker panel was identified and characterized using a training set (cohort I = 126), and tested against 2 test sets (cohort II = 222; cohort III = 174). The total number of samples used for each group is: HCC + CHB = 143, CHB = 211, control = 168. RESULTS: Our gene panel displays a consistent trend distinguishing HCC from controls in our test sets, with an area under receiver-operating characteristic curve of 0.9 in cohort III. Our independent test set (cohort III) showed that the gene panel had a sensitivity of 70% with a specificity of 92%. The biomarker profile for HCC was consistently detected in a small subgroup of CHB patients, thus potentially predicting early, preclinical cases of cancer that should be screened more intensively. CONCLUSION: The biomarkers identified in this study can be used as the basis of a blood-based test for the detection of early HCC in CHB.


Assuntos
Biomarcadores Tumorais/genética , Carcinoma Hepatocelular/diagnóstico , Carcinoma Hepatocelular/genética , Detecção Precoce de Câncer/métodos , Testes Genéticos , Hepatite B Crônica/complicações , Neoplasias Hepáticas/diagnóstico , Neoplasias Hepáticas/genética , RNA Neoplásico/genética , Adulto , Área Sob a Curva , Biomarcadores Tumorais/sangue , Carcinoma Hepatocelular/sangue , Carcinoma Hepatocelular/virologia , Estudos de Casos e Controles , Bases de Dados Genéticas , Feminino , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Redes Reguladoras de Genes , Estudo de Associação Genômica Ampla , Hepatite B Crônica/diagnóstico , Humanos , Neoplasias Hepáticas/sangue , Neoplasias Hepáticas/virologia , Malásia , Masculino , Pessoa de Meia-Idade , Análise de Sequência com Séries de Oligonucleotídeos , Valor Preditivo dos Testes , RNA Neoplásico/sangue , Curva ROC , Reação em Cadeia da Polimerase em Tempo Real , Reprodutibilidade dos Testes , Reação em Cadeia da Polimerase Via Transcriptase Reversa
10.
Epilepsia Open ; 7(3): 406-413, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35666848

RESUMO

OBJECTIVE: To assess the performance of a multimodal seizure detection device, first tested in adults (sensitivity 86%, PPV 49%), in a pediatric cohort living at home or residential care. METHODS: In this multicenter, prospective, video-controlled cohort-study, nocturnal seizures were detected by heartrate and movement changes in children with epilepsy and intellectual disability. Participants with a history of >1 monthly major motor seizure wore Nightwatch bracelet at night for 3 months. Major seizures were defined as tonic-clonic, generalized tonic >30 s, hyperkinetic, or clusters (>30 min) of short myoclonic or tonic seizures. The video of all events (alarms and nurse diaries) and about 10% of whole nights were reviewed to classify major seizures, and minor or no seizures. RESULTS: Twenty-three participants with focal or generalized epilepsy and nightly motor seizures were evaluated during 1511 nights, with 1710 major seizures. First 1014 nights, 4189 alarms occurred with average of 1.44/h, showing average sensitivity of 79.9% (median 75.4%) with mean PPV of 26.7% (median 11.1%) and false alarm rate of 0.2/hour. Over 90% of false alarms in children was due to heart rate (HR) part of the detection algorithm. To improve this rate, an adaptation was made such that the alarm was only triggered when the wearer was in horizontal position. For the remaining 497 nights, this was tested prospectively, 384 major seizures occurred. This resulted in mean PPV of 55.5% (median 58.1%) and a false alarm rate 0.08/h while maintaining a comparable mean sensitivity of 79.4% (median 93.2%). SIGNIFICANCE: Seizure detection devices that are used in bed which depend on heartrate and movement show similar sensitivity in children and adults. However, children do show general higher false alarm rate, mostly triggered while awake. By correcting for body position, the false alarms can be limited to a level that comes close to that in adults.


Assuntos
Epilepsia Tônico-Clônica , Epilepsia , Adulto , Algoritmos , Criança , Eletroencefalografia , Epilepsia/diagnóstico , Humanos , Estudos Prospectivos , Convulsões/diagnóstico
11.
Sci Rep ; 12(1): 9668, 2022 06 11.
Artigo em Inglês | MEDLINE | ID: mdl-35690597

RESUMO

Microscopy by Achromatic X-rays With Emission of Laminar Light (MAXWELL) is a new X-ray/visible technique with attractive characteristics including isotropic resolution in all directions, large-volume imaging and high throughput. An ultrathin, laminar X-ray beam produced by a Wolter type I mirror irradiates the sample stimulating the emission of visible light by scintillating nanoparticles, captured by an optical system. Three-dimensional (3D) images are obtained by scanning the specimen with respect to the laminar beam. We implemented and tested the technique with a high-brightness undulator at SPring-8, demonstrating its validity for a variety of specimens. This work was performed under the Synchrotrons for Neuroscience-an Asia-Pacific Strategic Enterprise (SYNAPSE) collaboration.


Assuntos
Microscopia , Síncrotrons , Imageamento Tridimensional , Luz , Microscopia/métodos , Tomografia Computadorizada por Raios X/métodos , Raios X
12.
Acta Neurol Belg ; 109(2): 81-90, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19681439

RESUMO

Action research is a form of research that enables practitioners to investigate and evaluate their own work. It is increasingly used in health care research; it is a research strategy in which the researcher and practitioners from the setting under study work together in projects aimed at generating new knowledge and simultaneously improving practice. This article gives an overview of the theoretical background of action research, its international historical development and explanations of its varied forms and related practical applications. Ethical problems are discussed as are questions of rigour The article shows that action research can be used to bridge the gap between theory and practice by generating knowledge fitting the particular circumstances in the practical setting, thereby avoiding problems of implementation of research findings due to lack of fit or lack of motivation. Action research lastingly increases the capacities of practitioners to solve problems encountered in practice.


Assuntos
Atenção à Saúde , Difusão de Inovações , Pesquisa sobre Serviços de Saúde/métodos , Pesquisa sobre Serviços de Saúde/ética , Pesquisa sobre Serviços de Saúde/história , História do Século XX , História do Século XXI , Humanos , Cooperação Internacional
13.
F1000Res ; 82019.
Artigo em Inglês | MEDLINE | ID: mdl-31807283

RESUMO

Rapid advances in sequencing technology have led to an explosive increase in the number of genetic variants identified in patients with neurological disease and have also enabled the assembly of a robust database of variants in healthy individuals. A surprising number of variants in the GRIN genes that encode N-methyl-D-aspartate (NMDA) glutamatergic receptor subunits have been found in patients with various neuropsychiatric disorders, including autism spectrum disorders, epilepsy, intellectual disability, attention-deficit/hyperactivity disorder, and schizophrenia. This review compares and contrasts the available information describing the clinical and functional consequences of genetic variations in GRIN2A and GRIN2B. Comparison of clinical phenotypes shows that GRIN2A variants are commonly associated with an epileptic phenotype but that GRIN2B variants are commonly found in patients with neurodevelopmental disorders. These observations emphasize the distinct roles that the gene products serve in circuit function and suggest that functional analysis of GRIN2A and GRIN2B variation may provide insight into the molecular mechanisms, which will allow more accurate subclassification of clinical phenotypes. Furthermore, characterization of the pharmacological properties of variant receptors could provide the first opportunity for translational therapeutic strategies for these GRIN-related neurological and psychiatric disorders.


Assuntos
Epilepsia , Transtornos Mentais/genética , Transtornos do Neurodesenvolvimento , Receptores de N-Metil-D-Aspartato , Esquizofrenia , Humanos , Transtornos do Neurodesenvolvimento/genética , Fenótipo , Receptores de N-Metil-D-Aspartato/genética
14.
J Adv Nurs ; 61(3): 261-72, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18197861

RESUMO

AIM: This paper is a report of an action research study aimed at improving decision-making concerning risks in people with epilepsy and intellectual disability and the empowerment of participants to sustain this improvement. BACKGROUND: Residents of long-stay units in specialized epilepsy centres suffer severe epilepsy and are often intellectually disabled. Professional caregivers have to find a balance between risk-taking and protection, as both can have a negative effect on quality of life. Clients, their representatives and caregivers are involved in this decision-making process. METHOD: A participative action research project was conducted. Data were gathered continuously over a 22-month period in 2004-2006 by interviews, observation, written reports of meetings and personal stories. FINDINGS: The action research resulted in an ongoing process of improvement. Problems in decision-making about risk were clarified. The importance of consensus about risks and commitment to risk management between all involved became apparent. Phases in risk management were discerned and used to adjust caregiving to clients' needs and capacities Assessment of client risk became more systematic and 'steps to an individual framework for decision-making' were developed as a tool for a systematic approach. CONCLUSION: Using an action research model to improve decision-making provided the preconditions for improving decision-making and risk management and suggesting a way to improve this process in this and other institutions.


Assuntos
Tomada de Decisões Gerenciais , Epilepsia/enfermagem , Deficiência Intelectual/enfermagem , Desenvolvimento de Programas , Atitude do Pessoal de Saúde , Epilepsia/psicologia , Feminino , Pesquisa sobre Serviços de Saúde , Humanos , Masculino , Relações Enfermeiro-Paciente/ética , Qualidade de Vida/psicologia , Gestão de Riscos/normas
15.
Neurology ; 91(21): e2010-e2019, 2018 11 20.
Artigo em Inglês | MEDLINE | ID: mdl-30355702

RESUMO

OBJECTIVE: To develop and prospectively evaluate a method of epileptic seizure detection combining heart rate and movement. METHODS: In this multicenter, in-home, prospective, video-controlled cohort study, nocturnal seizures were detected by heart rate (photoplethysmography) or movement (3-D accelerometry) in persons with epilepsy and intellectual disability. Participants with >1 monthly major seizure wore a bracelet (Nightwatch) on the upper arm at night for 2 to 3 months. Major seizures were tonic-clonic, generalized tonic >30 seconds, hyperkinetic, or others, including clusters (>30 minutes) of short myoclonic/tonic seizures. The video of all events (alarms, nurse diaries) and 10% completely screened nights were reviewed to classify major (needing an alarm), minor (needing no alarm), or no seizure. Reliability was tested by interobserver agreement. We determined device performance, compared it to a bed sensor (Emfit), and evaluated the caregivers' user experience. RESULTS: Twenty-eight of 34 admitted participants (1,826 nights, 809 major seizures) completed the study. Interobserver agreement (major/no major seizures) was 0.77 (95% confidence interval [CI] 0.65-0.89). Median sensitivity per participant amounted to 86% (95% CI 77%-93%); the false-negative alarm rate was 0.03 per night (95% CI 0.01-0.05); and the positive predictive value was 49% (95% CI 33%-64%). The multimodal sensor showed a better sensitivity than the bed sensor (n = 14, median difference 58%, 95% CI 39%-80%, p < 0.001). The caregivers' questionnaire (n = 33) indicated good sensor acceptance and usability according to 28 and 27 participants, respectively. CONCLUSION: Combining heart rate and movement resulted in reliable detection of a broad range of nocturnal seizures.


Assuntos
Deficiência Intelectual/complicações , Instituições Residenciais , Convulsões/diagnóstico , Dispositivos Eletrônicos Vestíveis , Acelerometria/instrumentação , Adolescente , Adulto , Idoso , Estudos de Coortes , Epilepsia/complicações , Feminino , Frequência Cardíaca/fisiologia , Humanos , Masculino , Pessoa de Meia-Idade , Movimento/fisiologia , Fotopletismografia/instrumentação , Estudos Prospectivos , Reprodutibilidade dos Testes , Convulsões/etiologia , Sono , Adulto Jovem
16.
Cryo Letters ; 28(6): 445-60, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-18183325

RESUMO

We compared cryopreservation of mammalian neural stem cells (NSCs) cultured as neurospheres by slow-cooling (1 C/min) in 10% (v/v) DMSO and cryopreservation by immersion into liquid nitrogen in ethylene glycol (EG)-sucrose solutions that support vitrification (40% (v/v) EG, 0.6 M sucrose) or that do not (37% v/v) EG, 0.6 M sucrose and 30% (v/v) EG, 0.6 M sucrose); the concentration of penetrating cryoprotectant in the last two solutions was lowered with the intention to reduce their toxicity towards NSCs. To protect against contamination a straw-in-straw technique was employed. Vitrification offered the best combination of preservation of structural integrity of neurospheres, cell viability (>96%), multipotency and karyotype. Rapid cooling in 37% (v/v) EG, 0.6 M sucrose afforded good viability but did not preserve structural integrity. Rapid cooling in 30% (v/v) EG, 0.6 M sucrose additionally reduced cell viability to 77%. Slow-cooling reduced cell viability to 65% and damaged the neurospheres. This study suggests that, in contrast to freezing, vitrification has immense potential for the cryopreservation of stem cells cultured as neurospheres or in other structured cultures.


Assuntos
Criopreservação/normas , Células-Tronco Multipotentes , Animais , Técnicas de Cultura de Células , Diferenciação Celular , Sobrevivência Celular , Criopreservação/métodos , Congelamento , Cariotipagem , Camundongos , Nitrogênio , Fatores de Tempo
17.
Chem Commun (Camb) ; 53(11): 1813-1816, 2017 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-28106899

RESUMO

Arachidonic acid derivatives equipped with either one or two fluorescent groups attached to the tip of the alkyl chains were synthesized and shown to function as inhibitor and substrate probes of cPLA2. The inhibitor probe was demonstrated to perform dual functions of inhibition and imaging while the substrate probe could be used for activity assay.


Assuntos
Citosol/enzimologia , Corantes Fluorescentes/química , Fosfolipases A2/análise , Fosfolipases A2/metabolismo , Ácido Araquidônico/metabolismo , Linhagem Celular , Corantes Fluorescentes/análise , Corantes Fluorescentes/síntese química , Humanos , Estrutura Molecular
18.
Sci Rep ; 7(1): 13683, 2017 10 20.
Artigo em Inglês | MEDLINE | ID: mdl-29057981

RESUMO

Cytosolic phospholipase A2 (cPLA2) is an enzyme that releases arachidonic acid (AA) for the synthesis of eicosanoids and lysophospholipids which play critical roles in the initiation and modulation of oxidative stress and neuroinflammation. In the central nervous system, cPLA2 activation is implicated in the pathogenesis of various neurodegenerative diseases that involves neuroinflammation, thus making it an important pharmacological target. In this paper, a new class of arachidonic acid (AA) analogues was synthesized and evaluated for their ability to inhibit cPLA2. Several compounds were found to inhibit cPLA2 more strongly than arachidonyl trifluoromethyl ketone (AACOCF3), an inhibitor that is commonly used in the study of cPLA2-related neurodegenerative diseases. Subsequent experiments concluded that one of the inhibitors was found to be cPLA2-selective, non-cytotoxic, cell and brain penetrant and capable of reducing reactive oxygen species (ROS) and nitric oxide (NO) production in stimulated microglial cells. Computational studies were employed to understand how the compound interacts with cPLA2.


Assuntos
Ácidos Araquidônicos/farmacologia , Inibidores de Fosfolipase A2/farmacologia , Fosfolipases A2/metabolismo , Animais , Ácidos Araquidônicos/química , Barreira Hematoencefálica/efeitos dos fármacos , Barreira Hematoencefálica/metabolismo , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Avaliação Pré-Clínica de Medicamentos , Humanos , Camundongos , Microglia/efeitos dos fármacos , Microglia/metabolismo , Simulação de Acoplamento Molecular , Óxido Nítrico/metabolismo , Inibidores de Fosfolipase A2/química , Espécies Reativas de Oxigênio/metabolismo
19.
Epilepsia Open ; 2(4): 424-431, 2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-29588973

RESUMO

Objective: Automated seizure detection and alarming could improve quality of life and potentially prevent sudden, unexpected death in patients with severe epilepsy. As currently available systems focus on tonic-clonic seizures, we want to detect a broader range of seizure types, including tonic, hypermotor, and clusters of seizures. Methods: In this multicenter, prospective cohort study, the nonelectroencephalographic (non-EEG) signals heart rate and accelerometry were measured during the night in patients undergoing a diagnostic video-EEG examination. Based on clinical video-EEG data, seizures were classified and categorized as clinically urgent or not. Seizures included for analysis were tonic, tonic-clonic, hypermotor, and clusters of short myoclonic/tonic seizures. Features reflecting physiological changes in heart rate and movement were extracted. Detection algorithms were developed based on stepwise fulfillment of conditions during increases in either feature. A training set was used for development of algorithms, and an independent test set was used for assessing performance. Results: Ninety-five patients were included, but due to sensor failures, data from only 43 (of whom 23 patients had 86 seizures, representing 402 h of data) could be used for analysis. The algorithms yield acceptable sensitivities, especially for clinically urgent seizures (sensitivity = 71-87%), but produce high false alarm rates (2.3-5.7 per night, positive predictive value = 25-43%). There was a large variation in the number of false alarms per patient. Significance: It seems feasible to develop a detector with high sensitivity, but false alarm rates are too high for use in clinical practice. For further optimization, personalization of algorithms may be necessary.

20.
Peptides ; 84: 44-57, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27498038

RESUMO

Relaxin-3 or insulin-like peptide 7 (INSL7) is the most recently discovered relaxin/insulin-like family peptide. Mature relaxin-3 consists of an A chain and a B chain held by disulphide bonds. According to structure activity relationship studies, the relaxin-3 B chain is more important in binding and activating the receptor. RXFP3 (also known as Relaxin-3 receptor 1, GPCR 135, somatostatin- and angiotensin- like peptide receptor or SALPR) was identified as the cognate receptor for relaxin-3 by expression profiles and binding studies. Recent studies imply roles of this system in mediating stress and anxiety, feeding, metabolism and cognition. Stapling of peptides is a technique used to develop peptide drugs for otherwise undruggable targets. The main advantages of stapling include, increased activity due to reduced proteolysis, increased affinity to receptors and increased cell permeability. Stable agonists and antagonists of RXFP3 are crucial for understanding the physiological significance of this system. So far, agonists and antagonists of RXFP3 are peptides. In this study, for the first time, we have introduced stapling of the relaxin-3 B chain at 14th and 18th positions (14s18) and 18th and 22nd position (18s22). These stapled peptides showed greater helicity than the unstapled relaxin-3 B chain in circular dichroism analysis. Both stapled peptides bound RXFP3 and activated RXFP3 as observed in an inhibition of forskolin-induced cAMP assay and a ERK1/2 activation assay, although with different potencies. Therefore, we conclude that stapling of the relaxin3 B chain does not compromise its ability to activate RXFP3 and is a promising method for developing stable peptide agonists and antagonists of RXFP3 to aid relaxin-3/RXFP3 research.


Assuntos
Peptídeos/genética , Receptores Acoplados a Proteínas G/genética , Relaxina/genética , Colforsina/farmacologia , AMP Cíclico/biossíntese , Células HEK293 , Humanos , Hidrocarbonetos/química , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Peptídeos/química , Ligação Proteica , Receptores Acoplados a Proteínas G/química , Receptores Acoplados a Proteínas G/metabolismo , Relaxina/química , Relaxina/metabolismo , Relação Estrutura-Atividade
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