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1.
Sci Rep ; 14(1): 6031, 2024 03 12.
Artigo em Inglês | MEDLINE | ID: mdl-38472404

RESUMO

The dysfunction of ion channels is a causative factor in a variety of neurological diseases, thereby defining the implicated channels as key drug targets. The detection of functional changes in multiple specific ionic currents currently presents a challenge, particularly when the neurological causes are either a priori unknown, or are unexpected. Traditional patch clamp electrophysiology is a powerful tool in this regard but is low throughput. Here, we introduce a single-shot method for detecting alterations amongst a range of ion channel types from subtle changes in membrane voltage in response to a short chaotically driven current clamp protocol. We used data assimilation to estimate the parameters of individual ion channels and from these we reconstructed ionic currents which exhibit significantly lower error than the parameter estimates. Such reconstructed currents thereby become sensitive predictors of functional alterations in biological ion channels. The technique correctly predicted which ionic current was altered, and by approximately how much, following pharmacological blockade of BK, SK, A-type K+ and HCN channels in hippocampal CA1 neurons. We anticipate this assay technique could aid in the detection of functional changes in specific ionic currents during drug screening, as well as in research targeting ion channel dysfunction.


Assuntos
Canais Iônicos , Neurônios , Eletrofisiologia , Canais Iônicos/metabolismo , Neurônios/metabolismo , Membrana Celular/metabolismo , Transporte de Íons
2.
Endocrinology ; 164(12)2023 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-37936337

RESUMO

The mechanism by which arcuate kisspeptin (ARNKISS) neurons co-expressing glutamate, neurokinin B, and dynorphin intermittently synchronize their activity to drive pulsatile hormone secretion remains unclear in females. In order to study spontaneous synchronization within the ARNKISS neuron network, acute brain slices were prepared from adult female Kiss1-GCaMP6 mice. Analysis of both spontaneous synchronizations and those driven by high frequency stimulation of individual ARNKISS neurons revealed that the network exhibits semi-random emergent excitation dependent upon glutamate signaling through AMPA receptors. No role for NMDA receptors was identified. In contrast to male mice, ongoing tachykinin receptor tone within the slice operated to promote spontaneous synchronizations in females. As previously observed in males, we found that ongoing dynorphin transmission in the slice did not contribute to synchronization events. These observations indicate that a very similar AMPA receptor-dependent mechanism underlies ARNKISS neuron synchronizations in the female mouse supporting the "glutamate two-transition" model for kisspeptin neuron synchronization. However, a potentially important sex difference appears to exist with a more prominent facilitatory role for tachykinin transmission in the female.


Assuntos
Dinorfinas , Kisspeptinas , Camundongos , Feminino , Masculino , Animais , Kisspeptinas/metabolismo , Dinorfinas/metabolismo , Núcleo Arqueado do Hipotálamo/metabolismo , Neurocinina B/metabolismo , Encéfalo/metabolismo , Neurônios/metabolismo , Glutamatos , Hormônio Liberador de Gonadotropina/metabolismo
3.
Cell Rep ; 42(1): 111914, 2023 01 31.
Artigo em Inglês | MEDLINE | ID: mdl-36640343

RESUMO

The mechanism by which arcuate nucleus kisspeptin (ARNKISS) neurons co-expressing glutamate, neurokinin B, and dynorphin intermittently synchronize their activity to generate pulsatile hormone secretion remains unknown. An acute brain slice preparation maintaining synchronized ARNKISS neuron burst firing was used alongside in vivo GCaMP GRIN lens microendoscope and fiber photometry imaging coupled with intra-ARN microinfusion. Studies in intact and gonadectomized male mice revealed that ARNKISS neuron synchronizations result from near-random emergent network activity within the population and that this was critically dependent on local glutamate-AMPA signaling. Whereas neurokinin B operated to potentiate glutamate-generated synchronizations, dynorphin-kappa opioid tone within the network served as a gate for synchronization initiation. These observations force a departure from the existing "KNDy hypothesis" for ARNKISS neuron synchronization. A "glutamate two-transition" mechanism is proposed to underlie synchronizations in this key hypothalamic central pattern generator driving mammalian fertility.


Assuntos
Dinorfinas , Neurocinina B , Camundongos , Masculino , Animais , Neurocinina B/metabolismo , Dinorfinas/metabolismo , Kisspeptinas/metabolismo , Núcleo Arqueado do Hipotálamo/metabolismo , Neurônios/metabolismo , Glutamatos , Hormônios , Mamíferos/metabolismo
4.
Gerontol Geriatr Med ; 8: 23337214221093891, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35958034

RESUMO

Aim: This systematic review aims to evaluate changes in Chinese older adults' psychosocial wellbeing after receiving horticultural therapy, and examine existing evidence regarding horticultural therapy's effectiveness in a Chinese setting. Method: Intervention studies measuring relevant outcomes amongst older adults and conducted in China were identified from ASSIA, CIHAHL Plus, PsycINFO, EMBASE, MEDLINE, SCOPUS, Web of Science Core Collection and CNKI. Cochrane risk of bias assessment tools were used to appraise study quality. Result: 16 studies were selected, among which four were published in English and 12 in Chinese. Findings suggested that after receiving horticultural therapy, older adults' psychosocial wellbeing is generally improved, but causal relationships between improvements and horticulture therapy were less clear. Conclusion: Features of horticultural therapy conducted in China is with its cultural and social uniqueness. Existing evidence supports the post-intervention benefits on completion of horticultural therapies, but the limitations in programme design, sample representativeness and methodological robustness limited the quality of the evidence.

5.
Neuropsychol Rehabil ; 32(1): 84-103, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32715913

RESUMO

Traumatic events can be associated with positive change, termed "post-traumatic growth." Existing resesarch suggests some overlap between post-traumatic growth and value-directed living. This study sought to explore the relationship between post-traumatic growth and value-directed living after acquired brain injury. Self-report questionnaires including the Posttraumatic Growth Inventory, Valued Living Questionnaire, Engaged Living Scale, Valuing Questionnaire, Hospital Anxiety and Depression Scale, World Health Organization Well-Being Index, Brief Resilience Scale, Trauma Screening Questionnaire and Glasgow Outcome Scale were posted to 317 individuals who had experienced a head injury, stroke or subarachnoid haemorrhage in the previous 3-13 years, with a hospital admission of minimum 7 days. Questionnaires were completed by 81 participants. Post-traumatic growth was significantly positively associated with two measures of value-directed living (VLQ, r = .269; VQ, r = .215). Higher levels of value-directed living were significantly associated with increased positive outcomes (wellbeing) and reduced negative outcomes (distress, post-traumatic stress symptoms). There was no significant association between post-traumatic growth and any of these outcomes. The association between post-traumatic growth and value-directed living indicates possible common underlying processes. Value-directed living appears to be a more useful concept, as it was associated with clinically relevant outcomes. It is recommended that value-directed living interventions are considered in brain injury rehabilitation.


Assuntos
Lesões Encefálicas Traumáticas , Lesões Encefálicas , Crescimento Psicológico Pós-Traumático , Lesões Encefálicas/complicações , Lesões Encefálicas Traumáticas/complicações , Humanos , Inquéritos e Questionários
6.
Epilepsy Behav Rep ; 16: 100491, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34746733

RESUMO

Idiopathic drop attacks are falls to the floor, without warning, and without loss of consciousness, for which the cause is uncertain. They are poorly studied but recent research suggests that many idiopathic drop attacks may be usefully considered within the spectrum of functional neurological disorder (FND). The aim of this study was to test a cognitive behavioural model of idiopathic drop attacks, in order to inform formulation and treatment. Interviews and diaries were completed by seven individuals experiencing drop attacks, and were analysed using a grounded theory qualitative data approach. Through the coding and synthesis of data into themes, a proposed cognitive behavioural model was identified, with a main precipitating event in all cases being a fall related to another cause, such as a mechanical fall or a fall due to medical reasons. Additional precipitating factors identified included situational triggers, high levels of stress, and dissociation. A maintaining cycle of thoughts, emotion and behaviour is outlined. Our proposed theory is consistent with current cognitive behavioural models of FND. A cognitive behavioural understanding of drop attacks when considered part of FND aids formulation in clinical practice, and suggests that cognitive behavioural therapy interventions for FND may also be applicable in this population.

7.
Nat Commun ; 10(1): 5309, 2019 12 03.
Artigo em Inglês | MEDLINE | ID: mdl-31796727

RESUMO

Bioelectronic medicine is driving the need for neuromorphic microcircuits that integrate raw nervous stimuli and respond identically to biological neurons. However, designing such circuits remains a challenge. Here we estimate the parameters of highly nonlinear conductance models and derive the ab initio equations of intracellular currents and membrane voltages embodied in analog solid-state electronics. By configuring individual ion channels of solid-state neurons with parameters estimated from large-scale assimilation of electrophysiological recordings, we successfully transfer the complete dynamics of hippocampal and respiratory neurons in silico. The solid-state neurons are found to respond nearly identically to biological neurons under stimulation by a wide range of current injection protocols. The optimization of nonlinear models demonstrates a powerful method for programming analog electronic circuits. This approach offers a route for repairing diseased biocircuits and emulating their function with biomedical implants that can adapt to biofeedback.


Assuntos
Neurônios/fisiologia , Animais , Tronco Encefálico/fisiologia , Hipocampo/fisiologia , Ativação do Canal Iônico , Canais Iônicos/metabolismo , Masculino , Modelos Neurológicos , Células Piramidais/fisiologia , Ratos Wistar , Respiração
8.
Front Cell Neurosci ; 12: 354, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30364232

RESUMO

N-methyl-D-aspartate receptors (NMDARs) are ubiquitously expressed in the mammalian brain and are essential for neuronal development, survival and plasticity. GluN2 subunit composition has a profound effect on the properties of NMDARs. In substantia nigra dopaminergic (SNc-DA) neurons, pharmacological experiments suggest that the relatively rare GluN2D subunits form functional synaptic and extrasynaptic NMDARs. Given the importance of establishing this point, mice lacking the GluN2D subunit (Grin2D-null) were used in this study to further explore the contribution of the GluN2D subunit to NMDAR responses. Significantly less DQP-1105-sensitive NMDAR-EPSC and significantly more ifenprodil-sensitive NMDAR-EPSC was observed in SNc-DA neurons from Grin2D-null mice, indicating that in these animals a small population of synaptic GluN2D subunits is replaced with GluN2B. Significantly larger currents were seen in response to higher concentrations (1-10 mM) of NMDA in SNc-DA neurons from Grin2D-null mice, as well as significantly more desensitization: these data are consistent with the presence of GluN2D-containing whole-cell NMDARs in SNc-DA neurons, with low conductance and little desensitization. Brief applications of NMDA evoked responses that were significantly less sensitive to DQP-1105 in slices from Grin2D-null mice. Tonic NMDAR activity in response to ambient extracellular glutamate, determined by the sensitivity of tonic current to D-AP5 (50 µM), was significantly less in SNc-DA neurons from Grin2D-null mice. In the presence of the glutamate transporter blocker TBOA (30 µM), the D-AP5-sensitive current was also significantly less in Grin2D-null mice. Taken together, these data support the evidence for GluN2D subunit expression in functional NMDARs at both synaptic and extrasynaptic locations in SNc-DA neurons.

9.
Arch Clin Neuropsychol ; 32(5): 507-518, 2017 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-28453602

RESUMO

OBJECTIVE: Cognitive deficits following stroke are well documented, but less is known about problems with social skills such as understanding others' thoughts and feelings. This study investigated the effect of stroke on a visual-affective measure of social understanding: the Reading the Mind in the Eyes test (RMET). The aims were to investigate whether right hemisphere stroke was particularly detrimental to this aspect of Theory of Mind (ToM), and investigate the relationship between ToM ability and executive function following stroke. METHODS: Performance of stroke patients (right hemisphere stroke, n = 15; left hemisphere stroke, n = 15) was compared to that of controls (n = 40) matched for age, years of education, and IQ on tasks measuring ToM and executive functioning. RESULTS: Right hemisphere stroke was associated with impaired ToM ability, but left hemisphere stroke was not. There was no effect of stroke on a matched non-ToM control task. High correlations were found between performance on the RMET and some measures of executive functioning in participants with right hemisphere stroke only. Further analyses suggested that deficits in executive functioning could not statistically explain all of the difficulties shown by stroke participants on the RMET. CONCLUSIONS: A reduction in the ability to attribute mental states to others following right hemisphere stroke may adversely affect psychosocial functioning, disrupt interpersonal relationships, and lead to reduced quality of life. The clinical importance of these findings, implications for clinical practice and future research are discussed.


Assuntos
Disfunção Cognitiva/fisiopatologia , Função Executiva/fisiologia , Lateralidade Funcional/fisiologia , Percepção Social , Acidente Vascular Cerebral/fisiopatologia , Teoria da Mente/fisiologia , Idoso , Idoso de 80 Anos ou mais , Disfunção Cognitiva/etiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Acidente Vascular Cerebral/complicações
10.
PLoS One ; 11(6): e0157004, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27300768

RESUMO

BACKGROUND: 3D cell cultures are emerging as more physiologically meaningful alternatives to monolayer cultures for many biological applications. They are attractive because they more closely mimic in vivo morphology, especially when co-cultured with stromal fibroblasts. METHODOLOGY/PRINCIPAL FINDINGS: We compared the efficacy of 3 different 3D cell culture systems; collagen I, low attachment culture vessels and a modification of Fibrolife®, a specialised humanised cell culture medium devoid of animal-derived components, using breast cancer cell lines representative of the different molecular subtypes of breast cancer, cultured alone or with human mammary fibroblasts with a view to developing matrix-free humanised systems. 3D collagen I culture supported the growth of a range of breast cancer cell lines. By modifying the composition of Fibrolife® to epiFL, matrix-free cell culture was possible. During sequential transfer to epiFL breast cancer cells gradually detached from the flask, growing progressively as spheroids. Phenotype was stable and reversible with cells remaining actively proliferating and easily accessible throughout culture. They could also be revived from frozen stocks. To achieve co-culture with fibroblasts in epiFL required use of low attachment culture vessels instead of standard plastic as fibroblasts remained adherent in epiFL. Here, cancer cell spheroids were allowed to form before adding fibroblasts. Immunohistochemical examination showed fibroblasts scattered throughout the epithelial spheroid, not dissimilar to the relationship of tumour stroma in human breast cancer. CONCLUSIONS: Because of its ease of handling, matrix-free 3D cell culture may be a useful model to study the influence of fibroblasts on breast cancer epithelial cells with use of epiFL culture medium taking this a step further towards a fully humanised 3D model. This methodology could be applied to other types of cancer cell lines, making this a versatile technique for cancer researchers wishing to use in vitro systems that better reflect cancer in vivo.


Assuntos
Neoplasias da Mama/patologia , Mama/citologia , Técnicas de Cocultura/métodos , Fibroblastos/citologia , Materiais Biocompatíveis/química , Mama/patologia , Adesão Celular , Linhagem Celular Tumoral , Sobrevivência Celular , Colágeno Tipo I/análise , Feminino , Fibroblastos/patologia , Humanos , Esferoides Celulares , Células Tumorais Cultivadas
11.
J Health Psychol ; 21(1): 16-27, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24505059

RESUMO

This qualitative study aimed to explore experiences of women currently undergoing specialist inpatient treatment for anorexia nervosa. Interviews were carried out with 21 women with a diagnosis of anorexia nervosa from a specialist adult inpatient eating disorder unit. Five master themes emerged using thematic analysis: (1) shifts in control, (2) experience of transition, (3) importance of supportive staff relationships, (4) sharing with peers and (5) process of recovery and self-discovery. Findings suggest that patients experience a process of change and adjustment in relation to levels of perceived personal control, attachment to the treatment environment and a sense of self-identity.


Assuntos
Anorexia Nervosa/terapia , Hospitalização , Relações Profissional-Paciente , Adolescente , Adulto , Anorexia Nervosa/psicologia , Feminino , Humanos , Pacientes Internados/psicologia , Pesquisa Qualitativa , Autocontrole/psicologia , Adulto Jovem
12.
CMAJ ; 184(7): E373-82, 2012 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-22431898

RESUMO

BACKGROUND: Cerebral glioma has a devastating impact on cognitive, physical, social, psychological and spiritual well-being. We sought to understand the multidimensional experience of patients with this form of cancer as they progressed from receiving a diagnosis to the terminal phase of the disease. METHODS: We recruited patients with a suspected brain tumour from a tertiary referral centre in the United Kingdom. We interviewed patients and their caregivers at key stages of the illness: before receiving a formal diagnosis, at the start of initial treatment, after initial treatment was completed and at six months' follow-up; caregivers were also interviewed postbereavement. We interviewed the patients' general practitioners once, after treatment had been completed. We transcribed the interviews and analyzed them thematically using the constant comparative method of a grounded theory approach. RESULTS: We conducted in-depth interviews with 26 patients, 23 of their relatives and 19 general practitioners. We saw evidence of physical, social, psychological and existential distress even before a diagnosis was confirmed. Social decline followed a similar trajectory to that of physical decline, whereas psychological and existential distress were typically acute around diagnosis and again after initial treatment. Each patient's individual course varied according to other factors including the availability of support and individual and family resources (e.g., personal resilience and emotional support). INTERPRETATION: There are practical ways that clinicians can care for patients with glioma and their caregivers, starting from before a diagnosis is confirmed. Understanding the trajectories of physical, social, psychological and existential well-being for these patients allows health care professionals to predict their patients' likely needs so they can provide appropriate support and sensitive and effective communication.


Assuntos
Cuidadores/psicologia , Família/psicologia , Glioma/psicologia , Saúde Mental , Apoio Social , Adulto , Idoso , Estudos Transversais , Existencialismo , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Psicologia Social , Pesquisa Qualitativa , Estresse Psicológico , Inquéritos e Questionários , Adulto Jovem
13.
Neuropsychiatr Dis Treat ; 3(3): 373-88, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19300568

RESUMO

OBJECTIVE: To develop a measure to assess post-acute outcome following from traumatic brain injury (TBI) with particular emphasis on the emotional and the behavioral outcome. The second objective was to assess the test-retest reliability, internal consistency, and factor structure of the newly developed patient version of the Head Injury Participation Scale (P-HIPS) and Patient-Head Injury Neurobehavioral Scale (P-HINAS). METHOD: Thirty-two TBI individuals and 27 carers took part in in-depth qualitative interviews exploring the consequences of the TBI. Interview transcripts were analyzed and key themes and concepts were used to construct the 49-item P-HIPS. A postal survey was then conducted on a cohort of 113 TBI patients to 'field test' the P-HIPS and the P-HINAS. RESULTS: All individual 49 items of the P-HIPS and their total score showed good test-retest reliability (0.93) and internal consistency (0.95). The P-HIPS showed a very good correlations with the Mayo Portland Adaptability Inventory-3 (MPAI-3) (0.87) and a moderate negative correlation with the Glasgow Outcome Scale-Extended (GOSE) (-0.51). Factor analysis extracted the following domains: 'Emotion/Behavior,' 'Independence/Community Living,' 'Cognition' and 'Physical'. The 'Emotion/Behavior' factor constituted the P-HINAS, which showed good internal consistency (0.93), test-retest reliability (0.91) and concurrent validity with MPAI subscale (0.82). CONCLUSIONS: Both the P-HIPS and the P-HINAS show strong psychometric properties. The qualitative methodology employed in the construction stage of the questionnaires provided good evidence of face and content validity.

14.
Neuropsychiatr Dis Treat ; 3(3): 389-408, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19300569

RESUMO

OBJECTIVE: Develop and assess the psychometric properties of the Carer - Head Injury Participation Scale (C-HIPS) and its biggest factor the Carer - Head Injury Neurobehavioral Assessment Scale (C-HINAS). Furthermore, the aim was to examine the inter-informant reliability by comparing the self reports of individuals with traumatic brain injury (TBI) with the carer reports on the C-HIPS and the C-HINAS. METHOD: Thirty-two TBI individuals and 27 carers took part in in-depth qualitative interviews exploring the consequences of the TBI. Interview transcripts were analysed and key themes and concepts were used to construct a 49-item and 58-item patient (Patient - Head Injury Participation Scale [P-HIPS]) and carer outcome measure (C-HIPS) respectively, of which 49 were parallel items and nine additional items were used to assess carer burden. Postal versions of the P-HIPS, C-HIPS, Mayo Portland Adaptability Inventory-3 (MPAI-3), and the Glasgow Outcome Scale-Extended (GOSE) were completed by a cohort of 113 TBI individuals and 80 carers. Data from a sub-group of 66 patient/carer pairs were used to compare inter-informant reliability between the P-HIPS and the C-HIPS, and the P-HINAS and the C-HINAS respectively. RESULTS: All individual 49 items of the C-HIPS and their total score showed good test-retest reliability (0.95) and internal consistency (0.95). Comparisons with the MPAI-3 and GOSE found a good correlation with the MPAI-3 (0.7) and a moderate negative correlation with the GOSE (-0.6). Factor analysis of these items extracted a 4-factor structure which represented the domains 'Emotion/Behavior' (C-HINAS), 'Independence/Community Living', 'Cognition', and 'Physical'. The C-HINAS showed good internal consistency (0.92), test-retest reliability (0.93), and concurrent validity with one MPAI subscale (0.7). Assessment of inter-informant reliability revealed good correspondence between the reports of the patients and the carers for both the C-HIPS (0.83) and the C-HINAS (0.82). CONCLUSION: Both the C-HINAS and the C-HIPS show strong psychometric properties. The qualitative methodology employed in the construction stage of the questionnaires provided good evidence of face and content validity. Comparisons between the P-HIPS and the C-HIPS, and the P-HINAS and the C-HINAS indicated high levels of agreement suggesting that in situations where the patient is unable to provide self-reports, information provided by the carer could be used.

15.
Am J Hum Biol ; 5(2): 237-241, 1993.
Artigo em Inglês | MEDLINE | ID: mdl-28524335

RESUMO

Plotting somatotypes is a convenient method for displaying variation in somatotype distributions. A program for drawing the somatochart and plotting somatotype data using SAS/GRAPH on the IBM mainframe is described. © 1993 Wiley-Liss, Inc.

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