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1.
Semin Cell Dev Biol ; 139: 55-72, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-35292192

RESUMO

The presubiculum (PRS) is an integral component of the perforant pathway that has recently been recognised as a relatively unscathed region in clinical Alzheimer's disease (AD), despite neighbouring components of the perforant pathway, CA1 and the entorhinal cortex, responsible for formation of episodic memory and storage, showing severe hallmarks of AD including, amyloid-beta (Aß) plaques, tau tangles and marked gliosis. However, the question remains whether this anatomical resilience translates into functional resilience of the PRS neurons. Using neuroanatomy combined with whole-cell electrophysiological recordings, we investigated whether the unique spatial profile of the PRS was replicable in two knock-in mouse models of AD, APPNL-F/NL-F, and APPNL-F/MAPTHTAU and whether the intrinsic properties and morphological integrity of the PRS principal neurons was maintained compared to the lateral entorhinal cortex (LEC) and hippocampal CA1 principal cells. Our data revealed an age-dependent Aß and tau pathology with neuroinflammation in the LEC and CA1, but a presence of fleece-like Aß deposits with an absence of tau tangles and cellular markers of gliosis in the PRS of the mouse models at 11-16 and 18-22 months. These observations were consistent in human post-mortem AD tissue. This spatial profile also correlated with functional resilience of strong burst firing PRS pyramidal cells that showed unaltered sub- and suprathreshold intrinsic biophysical membrane properties and gross morphology in the AD models that were similar to the properties of pyramidal cells recorded in age-matched wild-type mice (11-14 months). This was in contrast to the LEC and CA1 principal cells which showed altered subthreshold intrinsic properties such as a higher input resistance, longer membrane time constants and hyperexcitability in response to suprathreshold stimulation that correlated with atrophied dendrites in both AD models. In conclusion, our data show for the first time that the unique anatomical profile of the PRS constitutes a diffuse AD pathology that is correlated with the preservation of principal pyramidal cell intrinsic biophysical and morphological properties despite alteration of LEC and CA1 pyramidal cells in two distinct genetic models of AD. Understanding the underlying mechanisms of this resilience could be beneficial in preventing the spread of disease pathology before cognitive deficits are precipitated in AD.


Assuntos
Doença de Alzheimer , Camundongos , Humanos , Animais , Lactente , Doença de Alzheimer/metabolismo , Gliose/metabolismo , Gliose/patologia , Camundongos Transgênicos , Giro Para-Hipocampal/metabolismo , Giro Para-Hipocampal/patologia , Peptídeos beta-Amiloides/genética , Peptídeos beta-Amiloides/metabolismo , Placa Amiloide/metabolismo , Placa Amiloide/patologia , Modelos Animais de Doenças , Precursor de Proteína beta-Amiloide/genética , Precursor de Proteína beta-Amiloide/metabolismo
2.
Psychol Med ; 54(7): 1294-1308, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-37877259

RESUMO

BACKGROUND: People with borderline intellectual functioning (BIF) encounter greater social adversities than the general population and have an increased prevalence of mental illness. However, little is known about the socio-demographic characteristics and mental health of parents with BIF. METHODS: A secondary data analysis of the Adult Psychiatric Morbidity Survey 2014 was conducted. Logistic regression models were fitted to compare differences in socio-demographic, mental health and service-use characteristics between parents and non-parents with and without BIF, and to investigate if the relationship between parent status and mental health outcomes was modified by BIF status, sex, and employment. RESULTS: Data from 6872 participants was analyzed; 69.1% were parents. BIF parents had higher odds of common mental disorder, severe mental illness, post-traumatic stress disorder, self-harm/suicide and were more likely to see their General Practitioner (GP) and to receive mental health treatment than non-BIF parents. BIF parents did not have a higher prevalence of mental health problems than BIF non-parents. Being a parent, after adjusting for BIF status and other confounders, was associated with increased odds of having a common mental disorder, visits to see a GP and treatment for mental health. Female parents had higher odds of treatment for mental health problems. CONCLUSIONS: Being a parent is associated with elevated rates of common mental disorders. There is a higher burden of mental health problems and service use in people with BIF. A greater provision of specialist support services including ascertainment is indicated for this group.


Assuntos
Deficiência Intelectual , Deficiências da Aprendizagem , Transtornos Psicóticos , Transtornos de Estresse Pós-Traumáticos , Adulto , Humanos , Feminino , Saúde Mental , Inquéritos e Questionários , Deficiência Intelectual/epidemiologia , Deficiências da Aprendizagem/psicologia
3.
Aging Ment Health ; 28(3): 385-395, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-37811724

RESUMO

OBJECTIVES: As the life expectancy of individuals with intellectual disabilities (ID) continues to increase, there is an increased risk of developing dementia. While psychosocial interventions are gaining prominence, evidence is limited for people with both dementia and ID. This review discusses the effectiveness of direct psychosocial interventions and adaptations to facilitate delivery within this population. METHODS: The review followed the PRISMA guidelines. Five electronic databases, grey literature, and reference lists of included articles were searched for relevant studies. 10 eligible studies were appraised and analysed by narrative synthesis. RESULTS: Ten distinct interventions were identified and categorised based on their purpose and delivery. All interventions were beneficial in improving a range of outcomes, though some studies were of low quality and most had small samples. Common adaptations included simplification of tasks and material, higher staff-to-client ratio, and alternative communication methods. CONCLUSION: There is emerging evidence for several psychosocial interventions for people with ID and dementia, though further research is required on effectiveness and generalisability. The adaptations discussed may guide implementation into routine care and contribute to current policies and guidelines on improving ID and dementia care.


Assuntos
Demência , Deficiência Intelectual , Humanos , Intervenção Psicossocial , Deficiência Intelectual/terapia , Narração , Demência/terapia , Demência/psicologia
4.
Int J Mol Sci ; 25(10)2024 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-38791206

RESUMO

Dementia exists as a 'progressive clinical syndrome of deteriorating mental function significant enough to interfere with activities of daily living', with the most prevalent type of dementia being Alzheimer's disease (AD), accounting for about 80% of diagnosed cases. AD is associated with an increased risk of comorbidity with other clinical conditions such as hypertension, diabetes, and neuropsychiatric symptoms (NPS) including, agitation, anxiety, and depression as well as increased mortality in late life. For example, up to 70% of patients diagnosed with AD are affected by anxiety. As aging is the major risk factor for AD, this represents a huge global burden in ageing populations. Over the last 10 years, significant efforts have been made to recognize the complexity of AD and understand the aetiology and pathophysiology of the disease as well as biomarkers for early detection. Yet, earlier treatment options, including acetylcholinesterase inhibitors and glutamate receptor regulators, have been limited as they work by targeting the symptoms, with only the more recent FDA-approved drugs being designed to target amyloid-ß protein with the aim of slowing down the progression of the disease. However, these drugs may only help temporarily, cannot stop or reverse the disease, and do not act by reducing NPS associated with AD. The first-line treatment options for the management of NPS are selective serotonin reuptake inhibitors/selective noradrenaline reuptake inhibitors (SSRIs/SNRIs) targeting the monoaminergic system; however, they are not rational drug choices for the management of anxiety disorders since the GABAergic system has a prominent role in their development. Considering the overall treatment failures and side effects of currently available medication, there is an unmet clinical need for rationally designed therapies for anxiety disorders associated with AD. In this review, we summarize the current status of the therapy of AD and aim to highlight novel angles for future drug therapy in our ongoing efforts to alleviate the cognitive deficits and NPS associated with this devastating disease.


Assuntos
Doença de Alzheimer , Disfunção Cognitiva , Humanos , Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/etiologia , Disfunção Cognitiva/tratamento farmacológico , Disfunção Cognitiva/etiologia , Animais , Inibidores da Colinesterase/uso terapêutico
5.
Cochrane Database Syst Rev ; 2: CD003406, 2023 02 06.
Artigo em Inglês | MEDLINE | ID: mdl-36745863

RESUMO

BACKGROUND: Outwardly directed aggressive behaviour in people with intellectual disabilities is a significant issue that may lead to poor quality of life, social exclusion and inpatient psychiatric admissions. Cognitive and behavioural approaches have been developed to manage aggressive behaviour but the effectiveness of these interventions on reducing aggressive behaviour and other outcomes are unclear. This is the third update of this review and adds nine new studies, resulting in a total of 15 studies in this review. OBJECTIVES: To evaluate the efficacy of behavioural and cognitive-behavioural interventions on outwardly directed aggressive behaviour compared to usual care, wait-list controls or no treatment in people with intellectual disability. We also evaluated enhanced interventions compared to non-enhanced interventions. SEARCH METHODS: We used standard, extensive Cochrane search methods. The latest search date was March 2022. We revised the search terms to include positive behaviour support (PBS). SELECTION CRITERIA: We included randomised and quasi-randomised trials of children and adults with intellectual disability of any duration, setting and any eligible comparator. DATA COLLECTION AND ANALYSIS: We used standard Cochrane methods. Our primary outcomes were change in 1. aggressive behaviour, 2. ability to control anger, and 3. adaptive functioning, and 4. ADVERSE EFFECTS: Our secondary outcomes were change in 5. mental state, 6. medication, 7. care needs and 8. quality of life, and 9. frequency of service utilisation and 10. user satisfaction data. We used GRADE to assess certainty of evidence for each outcome. We expressed treatment effects as mean differences (MD) or odds ratios (OR), with 95% confidence intervals (CI). Where possible, we pooled data using a fixed-effect model. MAIN RESULTS: This updated version comprises nine new studies giving 15 included studies and 921 participants. The update also adds new interventions including parent training (two studies), mindfulness-based positive behaviour support (MBPBS) (two studies), reciprocal imitation training (RIT; one study) and dialectical behavioural therapy (DBT; one study). It also adds two new studies on PBS. Most studies were based in the community (14 studies), and one was in an inpatient forensic service. Eleven studies involved adults only. The remaining studies involved children (one study), children and adolescents (one study), adolescents (one study), and adolescents and adults (one study). One study included boys with fragile X syndrome. Six studies were conducted in the UK, seven in the USA, one in Canada and one in Germany. Only five studies described sources of funding. Four studies compared anger management based on cognitive behaviour therapy to a wait-list or no treatment control group (n = 263); two studies compared PBS with treatment as usual (TAU) (n = 308); two studies compared carer training on mindfulness and PBS with PBS only (n = 128); two studies involving parent training on behavioural approaches compared to wait-list control or TAU (n = 99); one study of mindfulness to a wait-list control (n = 34); one study of adapted dialectal behavioural therapy compared to wait-list control (n = 21); one study of RIT compared to an active control (n = 20) and one study of modified relaxation compared to an active control group (n = 12). There was moderate-certainty evidence that anger management may improve severity of aggressive behaviour post-treatment (MD -3.50, 95% CI -6.21 to -0.79; P = 0.01; 1 study, 158 participants); very low-certainty evidence that it might improve self-reported ability to control anger (MD -8.38, 95% CI -14.05 to -2.71; P = 0.004, I2 = 2%; 3 studies, 212 participants), adaptive functioning (MD -21.73, 95% CI -36.44 to -7.02; P = 0.004; 1 study, 28 participants) and psychiatric symptoms (MD -0.48, 95% CI -0.79 to -0.17; P = 0.002; 1 study, 28 participants) post-treatment; and very low-certainty evidence that it does not improve quality of life post-treatment (MD -5.60, 95% CI -18.11 to 6.91; P = 0.38; 1 study, 129 participants) or reduce service utilisation and costs at 10 months (MD 102.99 British pounds, 95% CI -117.16 to 323.14; P = 0.36; 1 study, 133 participants). There was moderate-certainty evidence that PBS may reduce aggressive behaviour post-treatment (MD -7.78, 95% CI -15.23 to -0.32; P = 0.04, I2 = 0%; 2 studies, 275 participants) and low-certainty evidence that it probably does not reduce aggressive behaviour at 12 months (MD -5.20, 95% CI -13.27 to 2.87; P = 0.21; 1 study, 225 participants). There was low-certainty evidence that PBS does not improve mental state post-treatment (OR 1.44, 95% CI 0.83 to 2.49; P = 1.21; 1 study, 214 participants) and very low-certainty evidence that it might not reduce service utilisation at 12 months (MD -448.00 British pounds, 95% CI -1660.83 to 764.83; P = 0.47; 1 study, 225 participants). There was very low-certainty evidence that mindfulness may reduce incidents of physical aggression (MD -2.80, 95% CI -4.37 to -1.23; P < 0.001; 1 study; 34 participants) and low-certainty evidence that MBPBS may reduce incidents of aggression post-treatment (MD -10.27, 95% CI -14.86 to -5.67; P < 0.001, I2 = 87%; 2 studies, 128 participants). Reasons for downgrading the certainty of evidence were risk of bias (particularly selection and performance bias); imprecision (results from single, often small studies, wide CIs, and CIs crossing the null effect); and inconsistency (statistical heterogeneity). AUTHORS' CONCLUSIONS: There is moderate-certainty evidence that cognitive-behavioural approaches such as anger management and PBS may reduce outwardly directed aggressive behaviour in the short term but there is less certainty about the evidence in the medium and long term, particularly in relation to other outcomes such as quality of life. There is some evidence to suggest that combining more than one intervention may have cumulative benefits. Most studies were small and there is a need for larger, robust randomised controlled trials, particularly for interventions where the certainty of evidence is very low. More trials are needed that focus on children and whether psychological interventions lead to reductions in the use of psychotropic medications.


Assuntos
Terapia Cognitivo-Comportamental , Deficiência Intelectual , Masculino , Adulto , Adolescente , Criança , Humanos , Qualidade de Vida , Terapia Cognitivo-Comportamental/métodos , Agressão , Cognição
6.
Int J Mol Sci ; 24(19)2023 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-37834366

RESUMO

Alzheimer's disease (AD) is the most common form of dementia, which disproportionately affects women. AD symptoms include progressive memory loss associated with amyloid-ß (Aß) plaques and dismantled synaptic mechanisms. Perineuronal nets (PNNs) are important components of the extracellular matrix with a critical role in synaptic stabilisation and have been shown to be influenced by microglia, which enter an activated state during AD. This study aimed to investigate whether sex differences affected the density of PNNs alongside the labelling of microglia and Aß plaques density.We performed neurochemistry experiments using acute brain slices from both sexes of the APPNL-F/NL-F mouse model of AD, aged-matched (2-5 and 12-16 months) to wild-type mice, combined with a weighted gene co-expression network analysis (WGCNA). The lateral entorhinal cortex (LEC) and hippocampal CA1, which are vulnerable during early AD pathology, were investigated and compared to the presubiculum (PRS), a region unscathed by AD pathology. The highest density of PNNs was found in the LEC and PRS regions of aged APPNL-F/NL-F mice with a region-specific sex differences. Analysis of the CA1 region using multiplex-fluorescent images from aged APPNL-F/NL-F mice showed regions of dense Aß plaques near clusters of CD68, indicative of activated microglia and PNNs. This was consistent with the results of WGCNA performed on normalised data on microglial cells isolated from age-matched, late-stage male and female wild-type and APP knock-in mice, which revealed one microglial module that showed differential expression associated with tissue, age, genotype, and sex, which showed enrichment for fc-receptor-mediated phagocytosis. Our data are consistent with the hypothesis that sex-related differences contribute to a disrupted interaction between PNNs and microglia in specific brain regions associated with AD pathogenesis.


Assuntos
Doença de Alzheimer , Feminino , Masculino , Camundongos , Humanos , Animais , Idoso , Doença de Alzheimer/metabolismo , Caracteres Sexuais , Camundongos Transgênicos , Peptídeos beta-Amiloides/metabolismo , Encéfalo/metabolismo , Placa Amiloide/metabolismo , Modelos Animais de Doenças , Precursor de Proteína beta-Amiloide/genética , Precursor de Proteína beta-Amiloide/metabolismo
7.
Aging Ment Health ; 26(4): 698-708, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33393364

RESUMO

OBJECTIVES: To examine the feasibility, acceptability and fidelity of individual Cognitive Stimulation Therapy (iCST) in people with intellectual disability (ID) and dementia. METHOD: We aimed to recruit forty dyads (carer and individual with dementia and ID) who were randomised to iCST or a waiting list control group. Both groups received treatment as usual. Family and paid carers delivered the manualised intervention (40 sessions over 20 weeks). Recruitment and retention of participants, intervention adherence, fidelity and acceptability were assessed. Outcome measures of cognition, adaptive functioning, quality of life (QoL) and carer outcomes were collected at baseline, midpoint (11 weeks) and at 21 weeks. Qualitative interviews were conducted with six carers about their experience of iCST. RESULTS: Forty dyads were recruited over 10 months from 12 National Health Service trusts. One dyad dropped out and 87.5% and 97.5% completed the midpoint and end-point assessments respectively. Assessment of fidelity indicated that the correct session structure was not followed; 70% completed at least 20 sessions and there was a high level of satisfaction with iCST. QoL was significantly higher in the iCST arm at 21 weeks (adjusted mean difference: 3.11; 95% CI: 0.64 to 5.58). There were no differences in the other outcome measures. CONCLUSION: The intervention was feasible and acceptable. A full-scale trial is warranted but some modifications are needed, including improved training and supervision for carers to improve fidelity.


Assuntos
Demência , Deficiência Intelectual , Cognição , Demência/psicologia , Demência/terapia , Estudos de Viabilidade , Humanos , Deficiência Intelectual/terapia , Qualidade de Vida , Medicina Estatal
8.
J Appl Res Intellect Disabil ; 35(6): 1297-1306, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35785506

RESUMO

BACKGROUND: People with intellectual disabilities are at risk of experiencing stigma and require the skills and confidence to deal with stigma in their daily lives. METHOD: Development and piloting of a 5-session manualised psychosocial group intervention designed to increase the capacity of people with intellectual disabilities aged 16+ to manage and resist stigma. Ten pre-existing groups (N = 67) in third sector and education settings participated. Interviews with participants (n = 26), facilitators (n = 9) and significant others (n = 7) 2-4 months after the intervention assessed perceived impact. RESULTS: Perceived benefits of the intervention for participants included increased understanding, improved connections with others, drive for advocacy, increased activity and self-efficacy, and opportunity to process difficult events and emotions. Differential impact depending on individuals' pre-existing self-advocacy skills was noted. CONCLUSIONS: This early-stage study indicates that further evaluation is merited to examine feasibility and outcomes of the STORM intervention.


Assuntos
Deficiência Intelectual , Intervenção Psicossocial , Estigma Social , Emoções , Direitos Humanos , Humanos , Deficiência Intelectual/psicologia
9.
Cereb Cortex ; 30(3): 1272-1290, 2020 03 14.
Artigo em Inglês | MEDLINE | ID: mdl-31407772

RESUMO

To understand the pathogenesis of specific neuronal circuit dysfunction in Alzheimer's disease (AD), we investigated the fate of three subclasses of "modulatory interneurons" in hippocampal CA1 using the AppNL-F/NL-F knock-in mouse model of AD. Cholecystokinin- and somatostatin-expressing interneurons were aberrantly hyperactive preceding the presence of the typical AD hallmarks: neuroinflammation and amyloid-ß (Aß) accumulation. These interneurons showed an age-dependent vulnerability to Aß penetration and a reduction in density and coexpression of the inhibitory neurotransmitter GABA synthesis enzyme, glutamic acid decarboxylase 67 (GAD67), suggesting a loss in their inhibitory function. However, calretinin (CR) interneurons-specialized to govern only inhibition, showed resilience to Aß accumulation, preservation of structure, and displayed synaptic hyperinhibition, despite the lack of inhibitory control of CA1 excitatory pyramidal cells from midstages of the disease. This aberrant inhibitory homeostasis observed in CA1 CR cells and pyramidal cells was "normalized" by blocking P2Y1 purinoreceptors, which were "upregulated" and strongly expressed in CR cells and astrocytes in AppNL-F/NL-F mice in the later stages of AD. In summary, AD-associated cell-type selective destruction of inhibitory interneurons and disrupted inhibitory homeostasis rectified by modulation of the upregulated purinoreceptor system may serve as a novel therapeutic strategy to normalize selective dysfunctional synaptic homeostasis during pathogenesis of AD.


Assuntos
Doença de Alzheimer/fisiopatologia , Região CA1 Hipocampal/fisiopatologia , Calbindina 2/fisiologia , Interneurônios/fisiologia , Inibição Neural , Receptores Purinérgicos P2Y1/fisiologia , Doença de Alzheimer/patologia , Peptídeos beta-Amiloides/metabolismo , Precursor de Proteína beta-Amiloide/genética , Animais , Região CA1 Hipocampal/patologia , Modelos Animais de Doenças , Técnicas de Introdução de Genes , Interneurônios/patologia , Masculino , Camundongos Endogâmicos C57BL , Regulação para Cima
10.
J Intellect Disabil ; : 17446295211002349, 2021 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-33896241

RESUMO

BACKGROUND: People with intellectual disability are among the most stigmatised groups in society. There is a paucity of studies reporting on how stigma is experienced in low- and middle-income countries. This study aims to explore the experience of stigma among adults with mild/moderate intellectual disability and the extent of their inclusion in Indonesian society. METHOD: Fifteen adults with mild/moderate intellectual disability were purposively recruited from three service providers and were interviewed using a semi-structured interview schedule. The data were analysed using thematic analysis. RESULTS: The findings suggest that adults with intellectual disability experience stigma in multiple settings (family, school, community), have limited access to social activities, and internalised the experienced stigma. CONCLUSION: This study adds to the international understanding of stigma experienced by adults with mild/moderate intellectual disability in daily life and their inclusion in society in a middle-income country.

11.
Cereb Cortex ; 29(4): 1834-1850, 2019 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-30766992

RESUMO

Synaptic dysfunction is widely proposed as an initial insult leading to the neurodegeneration observed in Alzheimer's disease (AD). We hypothesize that the initial insult originates in the lateral entorhinal cortex (LEC) due to deficits in key interneuronal functions and synaptic signaling mechanisms, in particular, Wnt (Wingless/integrated). To investigate this hypothesis, we utilized the first knock-in mouse model of AD (AppNL-F/NL-F), expressing a mutant form of human amyloid-ß (Aß) precursor protein. This model shows an age-dependent accumulation of Aß, neuroinflammation, and neurodegeneration. Prior to the typical AD pathology, we showed a decrease in canonical Wnt signaling activity first affecting the LEC in combination with synaptic hyperexcitation and severely disrupted excitatory-inhibitory inputs onto principal cells. This synaptic imbalance was consistent with a reduction in the number of parvalbumin-containing (PV) interneurons, and a reduction in the somatic inhibitory axon terminals in the LEC compared with other cortical regions. However, targeting GABAA receptors on PV cells using allosteric modulators, diazepam, zolpidem, or a nonbenzodiazepine, L-838,417 (modulator of α2/3 subunit-containing GABAA receptors), restored the excitatory-inhibitory imbalance observed at principal cells in the LEC. These data support our hypothesis, providing a rationale for targeting the synaptic imbalance in the LEC for early stage therapeutic intervention to prevent neurodegeneration in AD.


Assuntos
Doença de Alzheimer/fisiopatologia , Córtex Entorrinal/fisiopatologia , Neurônios/fisiologia , Sinapses/fisiologia , Doença de Alzheimer/patologia , Precursor de Proteína beta-Amiloide/genética , Precursor de Proteína beta-Amiloide/metabolismo , Animais , Modelos Animais de Doenças , Córtex Entorrinal/patologia , Humanos , Inflamação/patologia , Inflamação/fisiopatologia , Masculino , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Inibição Neural/fisiologia , Neurônios/patologia , Receptores de GABA-A/metabolismo , Sinapses/patologia , Técnicas de Cultura de Tecidos , Via de Sinalização Wnt
12.
Mol Psychiatry ; 23(9): 1851-1867, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-29904150

RESUMO

Benzodiazepines facilitate the inhibitory actions of GABA by binding to γ-aminobutyric acid type A receptors (GABAARs), GABA-gated chloride/bicarbonate channels, which are the key mediators of transmission at inhibitory synapses in the brain. This activity underpins potent anxiolytic, anticonvulsant and hypnotic effects of benzodiazepines in patients. However, extended benzodiazepine treatments lead to development of tolerance, a process which, despite its important therapeutic implications, remains poorly characterised. Here we report that prolonged exposure to diazepam, the most widely used benzodiazepine in clinic, leads to a gradual disruption of neuronal inhibitory GABAergic synapses. The loss of synapses and the preceding, time- and dose-dependent decrease in surface levels of GABAARs, mediated by dynamin-dependent internalisation, were blocked by Ro 15-1788, a competitive benzodiazepine antagonist, and bicuculline, a competitive GABA antagonist, indicating that prolonged enhancement of GABAAR activity by diazepam is integral to the underlying molecular mechanism. Characterisation of this mechanism has revealed a metabotropic-type signalling downstream of GABAARs, involving mobilisation of Ca2+ from the intracellular stores and activation of the Ca2+/calmodulin-dependent phosphatase calcineurin, which, in turn, dephosphorylates GABAARs and promotes their endocytosis, leading to disassembly of inhibitory synapses. Furthermore, functional coupling between GABAARs and Ca2+ stores was sensitive to phospholipase C (PLC) inhibition by U73122, and regulated by PLCδ, a PLC isoform found in direct association with GABAARs. Thus, a PLCδ/Ca2+/calcineurin signalling cascade converts the initial enhancement of GABAARs by benzodiazepines to a long-term downregulation of GABAergic synapses, this potentially underpinning the development of pharmacological and behavioural tolerance to these widely prescribed drugs.


Assuntos
Diazepam/metabolismo , Diazepam/farmacologia , Receptores de GABA-A/metabolismo , Animais , Benzodiazepinas/farmacologia , Calcineurina/metabolismo , Tolerância a Medicamentos/genética , Tolerância a Medicamentos/fisiologia , Antagonistas GABAérgicos/farmacologia , Moduladores GABAérgicos/metabolismo , Células HEK293 , Hipocampo/metabolismo , Humanos , Masculino , Neurônios/metabolismo , Fosfoinositídeo Fosfolipase C/metabolismo , Ratos , Ratos Sprague-Dawley , Receptores de GABA/metabolismo , Transdução de Sinais , Sinapses/metabolismo , Ácido gama-Aminobutírico/metabolismo
13.
Proc Natl Acad Sci U S A ; 113(8): E1108-15, 2016 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-26858411

RESUMO

Communication between neurons at chemical synapses is regulated by hundreds of different proteins that control the release of neurotransmitter that is packaged in vesicles, transported to an active zone, and released when an input spike occurs. Neurotransmitter can also be released asynchronously, that is, after a delay following the spike, or spontaneously in the absence of a stimulus. The mechanisms underlying asynchronous and spontaneous neurotransmitter release remain elusive. Here, we describe a model of the exocytotic cycle of vesicles at excitatory and inhibitory synapses that accounts for all modes of vesicle release as well as short-term synaptic plasticity (STSP). For asynchronous release, the model predicts a delayed inertial protein unbinding associated with the SNARE complex assembly immediately after vesicle priming. Experiments are proposed to test the model's molecular predictions for differential exocytosis. The simplicity of the model will also facilitate large-scale simulations of neural circuits.


Assuntos
Exocitose/fisiologia , Condução Nervosa/fisiologia , Plasticidade Neuronal/fisiologia , Neurotransmissores/metabolismo , Vesículas Sinápticas/metabolismo , Animais , Ratos
14.
J Appl Res Intellect Disabil ; 31(5): 643-658, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29441708

RESUMO

BACKGROUND: The aim of the study was to conduct the first systematic review investigating the prevalence of loneliness in people with intellectual developmental disabilities (IDD) and the interventions targeting loneliness. METHOD: A search across five databases was conducted (May 2016-June 2016). One reviewer (A. P.) selected the articles for inclusion and assessed their risk of bias using a standardized tool. The second reviewer (A. H.) examined the list of included/excluded articles and the ratings of the studies. RESULTS: Five prevalence studies met the inclusion criteria and provided an average loneliness prevalence of 44.74%. Only one intervention study was included, and it demonstrated that there was not any significant group difference for loneliness outcomes (p = .21). The majority of the studies had a weak quality rating. CONCLUSION: The systematic review evidenced that loneliness is a common experience in people with IDD and there is a need to extend current research.


Assuntos
Deficiências do Desenvolvimento/psicologia , Deficiência Intelectual/psicologia , Solidão/psicologia , Humanos
15.
J Urol ; 197(3 Pt 1): 647-654, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-27697580

RESUMO

PURPOSE: Irreversible electroporation has attractive attributes for focal ablation, namely nonthermal effect, precise demarcation of treatment and tissue selectivity. We report a prospective development study investigating focal irreversible electroporation. MATERIALS AND METHODS: A total of 20 men with certain characteristics were recruited for study, including a visible index lesion on anterior magnetic resonance imaging that was concordant with transperineal targeted and template prostate mapping biopsy, absent clinically significant disease noted elsewhere (University College London definition 2) and prostate specific antigen 15 ng/ml or less. Our primary objective was to determine the side effect profile at 12 months. Secondary objectives included the domain specific toxicity profile using patient reported outcomes and early disease control using magnetic resonance imaging targeted biopsy. RESULTS: A total of 19 patients with median age of 60 years (IQR 53-66) and median prostate specific antigen 7.75 ng/ml (IQR 5.5-10.03) were treated. Of the patients 16 were available for estimating the first outcome as 1 was lost to followup and 2 had received another form of treatment by study end. All 16 men had pad-free/leak-free continence at 12 months. The proportion of men with erection sufficient for penetration decreased from 12 of 16 (75%) to 11 of 16 (69%). No serious adverse events were recorded. There was a statistically significant improvement in urinary symptoms according to changes in UCLA-EPIC (UCLA Expanded Prostate Cancer Index Composite) and I-PSS (International Prostate Symptom Score) (p = 0.039 and 0.001, respectively). Erectile function remained stable according to the change in IIEF-15 (15-Item International Index of Erectile Function) (p = 0.572). Median prostate specific antigen significantly decreased to 1.71 ng/ml (p = 0.001). One man refused followup biopsy. No residual disease was found in 11 patients (61.1%). One man (5.6%) harbored clinically insignificant disease and the remaining 6 (33.3%) harbored clinically significant disease. CONCLUSIONS: Focal irreversible electroporation has low genitourinary toxicity. Additional studies are needed to optimize patient selection and treatment parameters.


Assuntos
Técnicas de Ablação , Eletroporação , Neoplasias da Próstata/cirurgia , Idoso , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Medidas de Resultados Relatados pelo Paciente , Estudos Prospectivos , Antígeno Prostático Específico , Neoplasias da Próstata/diagnóstico por imagem , Neoplasias da Próstata/patologia
16.
Soc Psychiatry Psychiatr Epidemiol ; 51(3): 465-74, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26498927

RESUMO

PURPOSE: The aim of this study was to investigate whether socio-demographic variables and physical disability (e.g. sensory impairment and mobility problems) were associated with self-reported stigma in people with intellectual disabilities (ID), and to examine whether age, sex and ethnicity modified the relationship between severity of intellectual disability and self-reported stigma. METHODS: 229 participants with mild or moderate intellectual disabilities were recruited from 12 centres/sites in England from community intellectual disability services, day centres, supported housing schemes, voluntary organisations and invitation letters. Information on physical disability and socio-demographic variables were obtained using a structured data collection form. Self-reported stigma was measured using a validated questionnaire. RESULTS: Age was associated with self-reported stigma, with older adults reporting more stigmatising experiences. Participants with moderate intellectual disabilities were more likely to report being treated differently such as being made fun of and being treated like children. Physical disability such as sensory, mobility and speech problems were not associated with self-reported stigma. Gender modified the relationship between severity of ID and self-reported stigma as participants who were male and had moderate ID were more likely to report stigma compared to females with moderate ID. Categorical age also modified the relationship between severity of ID and self-reported stigma as older participants who had moderate ID were more likely to report stigma compared to younger people with moderate ID. CONCLUSIONS: Older adults and those with moderate ID are potentially at higher risk of being targets of public stigma or are more likely to report stigma. Interventions to help individuals cope with stigma could be targeted to this group.


Assuntos
Pessoas com Deficiência/psicologia , Deficiência Intelectual/psicologia , Estigma Social , Adulto , Idoso , População Negra/psicologia , População Negra/estatística & dados numéricos , Estudos Transversais , Pessoas com Deficiência/estatística & dados numéricos , Inglaterra , Etnicidade/psicologia , Etnicidade/estatística & dados numéricos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Autorrelato , Índice de Gravidade de Doença , Fatores Socioeconômicos , População Branca/psicologia , População Branca/estatística & dados numéricos , Adulto Jovem
17.
Cochrane Database Syst Rev ; (4): CD003406, 2015 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-25847633

RESUMO

BACKGROUND: Outwardly-directed aggressive behaviour is a significant part of problem behaviours presented by people with intellectual disabilities. Prevalence rates of up to 50% have been reported in the literature, depending on the population sampled. Such behaviours often run a long-term course and are a major cause of social exclusion. This is an update of a previously published systematic review (see Hassiotis 2004; Hassiotis 2008). OBJECTIVES: To evaluate the efficacy of behavioural and cognitive-behavioural interventions on outwardly-directed aggressive behaviour in people with intellectual disabilities when compared to standard intervention or wait-list controls. SEARCH METHODS: In April 2014 we searched CENTRAL, Ovid MEDLINE, Embase, and eight other databases. We also searched two trials registers, checked reference lists, and handsearched relevant journals to identify any additional trials. SELECTION CRITERIA: We included studies if more than four participants (children or adults) were allocated by random or quasi-random methods to either intervention, standard treatment, or wait-list control groups. DATA COLLECTION AND ANALYSIS: Two review authors independently identified studies and extracted and assessed the quality of the data. MAIN RESULTS: We deemed six studies (309 participants), based on adult populations with intellectual disabilities, suitable for inclusion in the current version of this review. These studies examined a range of cognitive-behavioural therapy (CBT) approaches: anger management (three studies (n = 235); one individual therapy and two group-based); relaxation (one study; n = 12), mindfulness based on meditation (one study; n = 34), problem solving and assertiveness training (one study; n = 28). We were unable to include any studies using behavioural interventions. There were no studies of children.Only one study reported moderate quality of evidence for outcomes of interest as assessed by the Grades of Recommendations, Assessment, Development and Evaluation (GRADE) approach. We judged the evidence for the remaining studies to be of very low to low quality. Most studies were at risk of bias in two or more domains: one study did not randomly allocate participants and in two studies the process of randomisation was unclear; in one study there was no allocation concealment and in three studies this was unclear; blinding of assessors did not occur in three studies; incomplete outcome data were presented in one study and unclear in two studies; there was selective reporting in one study; and other biases were present in one study and unclear in four studies.Three of the six studies showed some benefit of the intervention on improving anger ratings. We did not conduct a meta-analysis, as we considered the studies too heterogeneous to combine (e.g. due to differences in the types of participants, sample size interventions, and outcome measures).Follow-up data for anger ratings for both the treatment and control groups were available for two studies. Only one of these studies (n = 161) had adequate long-term data (10 months), which found some benefit of treatment at follow-up (continued improvement in anger coping skills as rated by key workers; moderate-quality evidence).Two studies (n = 192) reported some evidence that the intervention reduces the number of incidents of aggression and one study (n = 28) reported evidence that the intervention improved mental health symptoms.One study investigated the effects of the intervention on quality of life and cost of health and social care utilisation. This study provided moderate-quality evidence, which suggests that compared to no treatment, behavioural or cognitive-behavioural interventions do not improve quality of life at 16 weeks (n = 129) or at 10 months follow-up (n = 140), or reduce the cost of health service utilisation (n = 133).Only one study (n = 28) assessed adaptive functioning. It reported evidence that assertiveness and problem-solving training improved adaptive behaviour.No studies reported data on adverse events. AUTHORS' CONCLUSIONS: The existing evidence on the effectiveness of behavioural and cognitive-behavioural interventions on outwardly-directed aggression in children and adults with intellectual disabilities is limited. There is a paucity of methodologically sound clinical trials and a lack of long-term follow-up data. Given the impact of such behaviours on the individual and his or her support workers, effective interventions are essential. We recommend that randomised controlled trials of sufficient power are carried out using primary outcomes that include reduction in outward-directed aggressive behaviour, improvement in quality of life, and cost effectiveness.


Assuntos
Agressão , Terapia Comportamental/métodos , Deficiências da Aprendizagem/psicologia , Transtornos do Comportamento Social/terapia , Adulto , Ira , Assertividade , Terapia Cognitivo-Comportamental , Humanos , Atenção Plena , Resolução de Problemas , Psicoterapia de Grupo , Ensaios Clínicos Controlados Aleatórios como Assunto , Violência
18.
Br J Pharmacol ; 2024 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-38886118

RESUMO

BACKGROUND: Alzheimer's disease (AD) is associated with gradual memory loss and anxiety which affects ~75% of AD patients. This study investigated whether AD-associated anxiety correlated with modulation of extrasynaptic δ-subunit-containing GABAA receptors (δ-GABAARs) in experimental mouse models of AD. EXPERIMENTAL APPROACH: We combined behavioural experimental paradigms to measure cognition performance, and anxiety with neuroanatomy and molecular biology, using familial knock-in (KI) mouse models of AD that harbour ß-amyloid (Aß) precursor protein App (AppNL-F) with or without humanized microtubule-associated protein tau (MAPT), age-matched to wild-type control mice at three different age windows. RESULTS: AppNL-F KI and AppNL-F/MAPT AD models showed a similar magnitude of cognitive decline and elevated magnitude of anxiety correlated with neuroinflammatory hallmarks, including triggering receptor expressed on myeloid cells 2 (TREM2), reactive astrocytes and activated microglia consistent with accumulation of Aß, tau and down-regulation of Wnt/ß-catenin signalling compared to aged-matched WT controls. In both the CA1 region of the hippocampus and dentate gyrus, there was an age-dependent decline in the expression of δ-GABAARs selectively expressed in parvalbumin (PV)-expressing interneurons, encapsulated by perineuronal nets (PNNs) in the AD mouse models compared to WT mice. In vivo positive allosteric modulation of the δ-GABAARs, using a δ-selective-compound DS2, decreased the level of anxiety in the AD mouse models, which was correlated with reduced hallmarks of neuroinflammation, and 'normalisation' of the expression of δ-GABAARs. CONCLUSIONS: Our data show that the δ-GABAARs could potentially be targeted for alleviating symptoms of anxiety, which would greatly improve the quality of life of AD individuals.

19.
Public Health Res (Southampt) ; 12(1): 1-111, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38327175

RESUMO

Background: Stigma contributes to the negative social conditions persons with intellectual disabilities are exposed to, and it needs tackling at multiple levels. Standing Up for Myself is a psychosocial group intervention designed to enable individuals with intellectual disabilities to discuss stigmatising encounters in a safe and supportive setting and to increase their self-efficacy in managing and resisting stigma. Objectives: To adapt Standing Up for Myself to make it suitable as a digital intervention; to evaluate the feasibility and acceptability of Digital Standing Up for Myself and online administration of outcome measures in a pilot; to describe usual practice in the context of the coronavirus disease 2019 pandemic to inform future evaluation. Design: Adaptation work followed by a single-arm pilot of intervention delivery. Setting and participants: Four third and education sector organisations. Individuals with mild-to-moderate intellectual disabilities, aged 16+, members of existing groups, with access to digital platforms. Intervention: Digital Standing Up for Myself intervention. Adapted from face-to-face Standing Up for Myself intervention, delivered over four weekly sessions, plus a 1-month follow-up session. Outcomes: Acceptability and feasibility of delivering Digital Standing Up for Myself and of collecting outcome and health economic measures at baseline and 3 months post baseline. Outcomes are mental well-being, self-esteem, self-efficacy in rejecting prejudice, reactions to discrimination and sense of social power. Results: Adaptation to the intervention required changes to session duration, group size and number of videos; otherwise, the content remained largely the same. Guidance was aligned with digital delivery methods and a new group member booklet was produced. Twenty-two participants provided baseline data. The intervention was started by 21 participants (four groups), all of whom were retained at 3 months. Group facilitators reported delivering the intervention as feasible and suggested some refinements. Fidelity of the intervention was good, with over 90% of key components observed as implemented by facilitators. Both facilitators and group members reported the intervention to be acceptable. Group members reported subjective benefits, including increased confidence, pride and knowing how to deal with difficult situations. Digital collection of all outcome measures was feasible and acceptable, with data completeness ≥ 95% for all measures at both time points. Finally, a picture of usual practice has been developed as an intervention comparator for a future trial. Limitations: The pilot sample was small. It remains unclear whether participants would be willing to be randomised to a treatment as usual arm or whether they could be retained for 12 months follow-up. Conclusions: The target number of groups and participants were recruited, and retention was good. It is feasible and acceptable for group facilitators with some training and supervision to deliver Digital Standing Up for Myself. Further optimisation of the intervention is warranted. Future work: To maximise the acceptability and reach of the intervention, a future trial could offer the adapted Digital Standing Up for Myself, potentially alongside the original face-to-face version of the intervention. Study registration: This study was registered as ISRCTN16056848. Funding: This award was funded by the National Institute for Health and Care Research (NIHR) Public Health Research programme (NIHR award ref: 17/149/03) and is published in full in Public Health Research; Vol. 12, No. 1. See the NIHR Funding and Awards website for further award information.


People with intellectual disabilities (or 'learning disabilities' in United Kingdom language) are more likely to experience poor physical and mental health than the general population. Stigma (negative stereotypes, prejudice and discrimination) has been linked to lower self-esteem, quality of life, and mental and physical ill health. Efforts to empower people with intellectual disabilities themselves to challenge stigma with a view to improving well-being, health and self-esteem are lacking. In 2017, we developed Standing Up for Myself, a brief group-based programme for people with mild-to-moderate intellectual disabilities aged 16+ to address this gap. As this study got underway, face-to-face meetings were suspended due to the coronavirus disease 2019 pandemic. We used the opportunity to assess whether Standing Up for Myself could be delivered through web-based meetings. We adapted Standing Up for Myself for digital delivery, with close input from advisors with intellectual disabilities and experienced group facilitators. We then tested the digital version in charity and education settings to evaluate if Digital Standing Up for Myself could be delivered as planned and how acceptable it was to group facilitators and participants. Four groups, with a total of 22 members, signed up to try Digital Standing Up for Myself. One participant dropped out before starting Standing Up for Myself, and the other 21 continued until the end of the programme. Retention and attendance were good; participants on average attended four of the five sessions. Ninety per cent of the core programme requirements were fully delivered as detailed in the Digital Standing Up for Myself manual. Problems with technology were manageable, although facilitators found using the Standing Up for Myself Wiki platform (an online platform for storage and sharing of resources) difficult, particularly when sharing video content. Facilitators felt acceptable levels of privacy were achieved and there were no reports of undue distress. All facilitators and many group members said they would recommend Digital Standing Up for Myself to others. Group members shared how the programme benefitted them, noting increased awareness about disabilities, and for some increased confidence, pride and independence. Some had learnt how to stand up for themselves and manage difficult situations and took pride in this. Completing outcome and health cost measures via web-based meetings was acceptable and data were largely fully complete and useable.


Assuntos
Deficiência Intelectual , Humanos , Adulto , Adolescente , Estudos de Viabilidade , Avaliação de Resultados em Cuidados de Saúde , Autoeficácia , Emoções
20.
J Neurophysiol ; 109(1): 216-24, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23054605

RESUMO

Endogenous cannabinoid type 1 (CB1) receptors demonstrate a cell type-specific expression and are potent modulators of synaptic transmission within the central nervous system. We aimed to investigate whether two classes of multipolar interneuron in the neocortex displayed a form of short-term synaptic plasticity, depolarization-induced suppression of inhibition (DSI), and whether the DSI was mediated by a common receptor. Paired whole cell recordings combined with biocytin labeling were performed between pyramidal cells and either multipolar adapting or multipolar nonadapting interneurons in layers II-IV of male Wistar rat (postnatal day 17-22) somatosensory cortex. Inhibitory postsynaptic potentials elicited by multipolar adapting interneurons were sensitive to DSI, which was blocked by the CB1 receptor antagonist AM-251 (8 µM), indicating that the suppression of inhibition was mediated by CB1 receptors. Two subpopulations of multipolar nonadapting interneuron-to-pyramidal cell connections were discovered on the basis of their susceptibility to DSI. Whereas 50% were insensitive to DSI, the remaining half were sensitive to DSI, which could not be prevented by AM-251. DSI at these connections was also insensitive to the group I (mGluRIa) and III metabotropic glutamate receptor antagonists (RS)-1-aminoindan-1,5-dicarboxylic acid (100 µM) and (RS)-α-cyclopropyl-4-phosphonophenylglycine (100 µM) and the group III agonist l-2-amino-4-phosphonobutanoate (50 µM). However, multipolar nonadapting interneuron-to-pyramidal cell connections were sensitive to the endocannabinoid anandamide (9 µM), mimicking the effects of DSI, which also could not be prevented by AM-251, implying a CB1 receptor-independent suppression of inhibition. These results reveal an interneuron type-specific modulation of synaptic transmission via CB receptors in the neocortex.


Assuntos
Potenciais Pós-Sinápticos Inibidores/fisiologia , Interneurônios/fisiologia , Neocórtex/fisiologia , Inibição Neural/fisiologia , Células Piramidais/fisiologia , Receptor CB1 de Canabinoide/fisiologia , Animais , Ácidos Araquidônicos/farmacologia , Agonistas de Receptores de Canabinoides/farmacologia , Antagonistas de Receptores de Canabinoides/farmacologia , Endocanabinoides/farmacologia , Potenciais Pós-Sinápticos Inibidores/efeitos dos fármacos , Interneurônios/efeitos dos fármacos , Masculino , Neocórtex/efeitos dos fármacos , Inibição Neural/efeitos dos fármacos , Técnicas de Patch-Clamp , Piperidinas/farmacologia , Alcamidas Poli-Insaturadas/farmacologia , Células Piramidais/efeitos dos fármacos , Pirazóis/farmacologia , Ratos , Ratos Wistar , Transmissão Sináptica/efeitos dos fármacos , Transmissão Sináptica/fisiologia
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