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1.
bioRxiv ; 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38798487

RESUMO

Tau reduction is a promising therapeutic strategy for Alzheimer's disease. In numerous models, tau reduction via genetic knockout is beneficial, at least in part due to protection against hyperexcitability and seizures, but the underlying mechanisms are unclear. Here we describe the generation and initial study of a new conditional Tau flox model to address these mechanisms. Given the protective effects of tau reduction against hyperexcitability, we compared the effects of selective tau reduction in excitatory or inhibitory neurons. Tau reduction in excitatory neurons mimicked the protective effects of global tau reduction, while tau reduction in inhibitory neurons had the opposite effect and increased seizure susceptibility. Since most prior studies used knockout mice lacking tau throughout development, we crossed Tau flox mice with inducible Cre mice and found beneficial effects of tau reduction in adulthood. Our findings support the effectiveness of tau reduction in adulthood and indicate that excitatory neurons may be a key site for its excitoprotective effects. SUMMARY: A new conditional tau knockout model was generated to study the protective effects of tau reduction against hyperexcitability. Conditional tau reduction in excitatory, but not inhibitory, neurons was excitoprotective, and induced tau reduction in adulthood was excitoprotective without adverse effects.

2.
J Pain Symptom Manage ; 65(6): 532-540, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36801354

RESUMO

CONTEXT: Despite high rates of mortality among infants in the Southern U.S., little is known about the timing of pediatric palliative care (PPC), the intensity of end-of-life care, and whether there are differences among sociodemographic characteristics. OBJECTIVES: To describe PPC patterns and treatment intensity during the last 48 hours of life among neonatal intensive care unit (NICU) patients in the Southern U.S. who received specialized PPC. METHODS: Medical record abstraction of infant decedents who received PPC consultation in two NICUs (in Alabama and Mississippi) from 2009 to 2017 (n = 195) including clinical characteristics, palliative and end-of-life care characteristics, patterns of PPC, and intensive medical treatments in the last 48 hours of life. RESULTS: The sample was racially (48.2% Black) and geographically (35.4% rural) diverse. Most infants died after withdrawal of life-sustaining interventions (58%) and had do not attempt resuscitation orders documented (75.9%); very few infants enrolled in hospice (6.2%). Initial PPC consult occurred a median of 13 days after admission and a median of 17 days before death. Infants with a primary diagnosis of genetic or congenital anomaly received earlier PPC consultation (P = 0.02) compared to other diagnoses. In the last 48 hours of life, NICU patients received intensive interventions including mechanical ventilation (81.5%), CPR (27.7%) and surgeries or invasive procedures (25.1%). Black infants were more likely to receive CPR compared to White infants (P = 0.04). CONCLUSION: Overall, PPC consultation occurred late in NICU hospitalizations, infants received high-intensity medical interventions in the last 48 hours of life, and there are disparities in intensity of treatment interventions at end of life. Further research is needed to explore if these patterns of care reflect parent preferences and goal concordance.


Assuntos
Cuidados Paliativos na Terminalidade da Vida , Assistência Terminal , Lactente , Recém-Nascido , Humanos , Criança , Terapia Intensiva Neonatal , Estudos Retrospectivos , Assistência Terminal/métodos , Cuidados Paliativos/métodos
3.
J Nucl Cardiol ; 29(6): 2812, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36322375
4.
Neurobiol Dis ; 124: 531-543, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30625365

RESUMO

Temporal Lobe Epilepsy (TLE) is frequently associated with changes in protein composition and post-translational modifications (PTM) that exacerbate the disorder. O-linked-ß-N-acetyl glucosamine (O-GlcNAc) is a PTM occurring at serine/threonine residues that is derived from and closely associated with metabolic substrates. The enzymes O-GlcNActransferase (OGT) and O-GlcNAcase (OGA) mediate the addition and removal, respectively, of the O-GlcNAc modification. The goal of this study was to characterize OGT/OGA and protein O-GlcNAcylation in the epileptic hippocampus and to determine and whether direct manipulation of these proteins and PTM's alter epileptiform activity. We observed reduced global and protein specific O-GlcNAcylation and OGT expression in the kainate rat model of TLE and in human TLE hippocampal tissue. Inhibiting OGA with Thiamet-G elevated protein O-GlcNAcylation, and decreased both seizure duration and epileptic spike events, suggesting that OGA may be a therapeutic target for seizure control. These findings suggest that loss of O-GlcNAc homeostasis in the kainate model and in human TLE can be reversed via targeting of O-GlcNAc related pathways.


Assuntos
Epilepsia do Lobo Temporal/metabolismo , Glucosamina/metabolismo , Hipocampo/metabolismo , Homeostase/fisiologia , Processamento de Proteína Pós-Traducional/fisiologia , Animais , Histona Acetiltransferases/metabolismo , Humanos , Masculino , N-Acetilglucosaminiltransferases/metabolismo , Ratos , Ratos Sprague-Dawley
6.
BMJ Support Palliat Care ; 8(4): 468-474, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26310525

RESUMO

BACKGROUND: Despite apparent unmet needs, people with chronic obstructive pulmonary disease (COPD) rarely ask for help. We explored the concept of need from the perspective of patients, their family carers and professionals. METHODS: We recruited inpatients at two National Health Service (NHS) Lothian hospitals to a structured, holistic review of care needs delivered at home by a respiratory nurse 4 weeks postdischarge. Using semistructured interviews and group discussions, review notes and field-notes we explored the views of patients, carers and professionals on perceptions of need and the actions requested. Data were analysed thematically using Bradshaw's classification of need. RESULTS: 14 patients, 3 carers, 28 professionals provided 36 interviews and 2 discussion groups. Few needs were identified by our intervention and few actions planned. Professionals identified 'normative' needs some of which had been addressed during routine discharge planning. Other needs (physical/psychological limitations, social/financial concerns, existential issues) were 'felt' by patients and carers but articulated in response to the researcher's questions rather than actively 'expressed'. Patients often did not wish any action to address the problems, preferring care from family members rather than formal agencies. Many spoke of the over-arching importance of retaining a sense of independence and autonomy, considering themselves as ageing rather than ill. CONCLUSIONS: In contrast to professionally-defined 'normative' needs, patients rarely perceived themselves as needy, accepting their 'felt' needs as the result of a disability to which they had now adapted. Sensitive approaches that foster independence may enable patients to 'express' needs that are amenable to help without disturbing the adaptive equilibrium they have achieved. TRIAL REGISTRATION NUMBER: NCT01650480.


Assuntos
Cuidadores/psicologia , Família/psicologia , Pessoal de Saúde/psicologia , Necessidades e Demandas de Serviços de Saúde , Doença Pulmonar Obstrutiva Crônica/psicologia , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Avaliação das Necessidades , Pesquisa Qualitativa , Escócia
7.
J Neurosci ; 37(34): 8207-8215, 2017 08 23.
Artigo em Inglês | MEDLINE | ID: mdl-28760863

RESUMO

O-GlcNAcylation is a ubiquitous and dynamic post-translational modification involving the O-linkage of ß-N-acetylglucosamine to serine/threonine residues of membrane, cytosolic, and nuclear proteins. This modification is similar to phosphorylation and regarded as a key regulator of cell survival and homeostasis. Previous studies have shown that phosphorylation of serine residues on synaptic proteins is a major regulator of synaptic strength and long-term plasticity, suggesting that O-GlcNAcylation of synaptic proteins is likely as important as phosphorylation; however, few studies have investigated its role in synaptic efficacy. We recently demonstrated that acutely increasing O-GlcNAcylation induces a novel form of LTD at CA3-CA1 synapses, O-GlcNAc LTD. Here, using hippocampal slices from young adult male rats and mice, we report that epileptiform activity at CA3-CA1 synapses, generated by GABAAR inhibition, is significantly attenuated when protein O-GlcNAcylation is pharmacologically increased. This dampening effect is lost in slices from GluA2 KO mice, indicating a requirement of GluA2-containing AMPARs, similar to expression of O-GlcNAc LTD. Furthermore, we find that increasing O-GlcNAcylation decreases spontaneous CA3 pyramidal cell activity under basal and hyperexcitable conditions. This dampening effect was also observed on cortical hyperexcitability during in vivo EEG recordings in awake mice where the effects of the proconvulsant pentylenetetrazole are attenuated by acutely increasing O-GlcNAcylation. Collectively, these data demonstrate that the post-translational modification, O-GlcNAcylation, is a novel mechanism by which neuronal and synaptic excitability can be regulated, and suggest the possibility that increasing O-GlcNAcylation could be a novel therapeutic target to treat seizure disorders and epilepsy.SIGNIFICANCE STATEMENT We recently reported that an acute pharmacological increase in protein O-GlcNAcylation induces a novel form of long-term synaptic depression at hippocampal CA3-CA1 synapses (O-GlcNAc LTD). This synaptic dampening effect on glutamatergic networks suggests that increasing O-GlcNAcylation will depress pathological hyperexcitability. Using in vitro and in vivo models of epileptiform activity, we show that acutely increasing O-GlcNAc levels can significantly attenuate ongoing epileptiform activity and prophylactically dampen subsequent seizure activity. Together, our findings support the conclusion that protein O-GlcNAcylation is a regulator of neuronal excitability, and it represents a promising target for further research on seizure disorder therapeutics.


Assuntos
Acetilglucosamina/metabolismo , Epilepsia/metabolismo , Epilepsia/fisiopatologia , Hipocampo/metabolismo , Hipocampo/fisiopatologia , Depressão Sináptica de Longo Prazo/fisiologia , Animais , Epilepsia/prevenção & controle , Feminino , Glicosilação , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Técnicas de Cultura de Órgãos , Processamento de Proteína Pós-Traducional/fisiologia , Ratos , Ratos Sprague-Dawley
8.
Health Expect ; 19(3): 602-16, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-25523361

RESUMO

BACKGROUND: Sharing the electronic health-care record (EHR) during consultations has the potential to facilitate patient involvement in their health care, but research about this practice is limited. METHODS: We used multichannel video recordings to identify examples and examine the practice of screen-sharing within 114 primary care consultations. A subset of 16 consultations was viewed by the general practitioner and/or patient in 26 reflexive interviews. Screen-sharing emerged as a significant theme and was explored further in seven additional patient interviews. Final analysis involved refining themes from interviews and observation of videos to understand how screen-sharing occurred, and its significance to patients and professionals. RESULTS: Eighteen (16%) of 114 videoed consultations involved instances of screen-sharing. Screen-sharing occurred in six of the subset of 16 consultations with interviews and was a significant theme in 19 of 26 interviews. The screen was shared in three ways: 'convincing' the patient of a diagnosis or treatment; 'translating' between medical and lay understandings of disease/medication; and by patients 'verifying' the accuracy of the EHR. However, patients and most GPs perceived the screen as the doctor's domain, not to be routinely viewed by the patient. CONCLUSIONS: Screen-sharing can facilitate patient involvement in the consultation, depending on the way in which sharing comes about, but the perception that the record belongs to the doctor is a barrier. To exploit the potential of sharing the screen to promote patient involvement, there is a need to reconceptualise and redesign the EHR.


Assuntos
Registros Eletrônicos de Saúde , Participação do Paciente/psicologia , Relações Médico-Paciente , Adulto , Idoso , Idoso de 80 Anos ou mais , Comunicação , Periféricos de Computador , Feminino , Humanos , Entrevistas como Assunto , Masculino , Pessoa de Meia-Idade , Atenção Primária à Saúde , Vitória , Gravação em Vídeo
9.
BMC Fam Pract ; 16: 176, 2015 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-26651488

RESUMO

BACKGROUND: Since 2012, all GP practices across Scotland have been supported to take a systematic approach to end-of-life care, by helping them to identify more patients for palliative care through a Palliative Care Directed Enhanced Service (DES). We aimed to understand the impact of this initiative. METHODS: Routine quantitative data from the 2012/13, and 2013/14 DES were collected from regional health boards, analysed and discussed. Qualitative data were collected from a sample of 2012/13 DES returns and analysed using Thematic Analysis. RESULTS: Data were received from 512 practices in nine Scottish Health boards for the 2012-13 DES and 638 practices in 11 Health boards for 2013-14. A sample of 90 of the returns for 2012-13 was selected for qualitative analysis. In 2012-13, 72 % of patients who died of cancer were listed on the palliative care register (PCR) before death while 27 % of patients who died as a result of non-malignant conditions were listed on the PCR. In 2013-14, cancer identification remained the same but identification of people dying with other long-term conditions had improved to 32.5 %. We identified several key issues needed to improve palliative care in the community. The need for training to identify patients with palliative care needs (particularly non-cancer); communication skills training; improvements in sharing information across the NHS; under-resource of and lack of coordination with district nurses; improvements in information technology; and tools for working with enlarged palliative care registers. CONCLUSIONS: The DES helped more patients with long-term conditions (LTC) receive generalist palliative care. Approaching generalist palliative care as anticipatory care could facilitate communication between GPs and patients/families and remove some barriers to early identification of palliative care needs. Improvement of information technology and use of identification tools like the SPICT™ may improve professionals' communication with each other and help may make identification and management of patients easier.


Assuntos
Atitude do Pessoal de Saúde , Cuidados Paliativos/normas , Atenção Primária à Saúde/normas , Pesquisa Qualitativa , Melhoria de Qualidade/organização & administração , Feminino , Humanos , Masculino , Cuidados Paliativos/tendências , Atenção Primária à Saúde/tendências , Estudos Retrospectivos , Escócia , Medicina Estatal/normas
10.
Hum Mol Genet ; 24(23): 6667-74, 2015 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-26358779

RESUMO

CD2-associated protein (CD2AP) is a leading genetic risk factor for Alzheimer's disease, but little is known about the function of CD2AP in the brain. We studied CD2AP(-/-) mice to address this question. Because CD2AP(-/-) mice normally die by 6 weeks from nephrotic syndrome, we used mice that also express a CD2AP transgene in the kidney, but not brain, to attenuate this phenotype. CD2AP-deficient mice had no behavioral abnormalities except for mild motor and anxiety deficits in a subset of CD2AP(-/-) mice exhibiting severe nephrotic syndrome, associated with systemic illness. Pentylenetetrazol (PTZ)-induced seizures occurred with shorter latency in CD2AP(-/-) mice, but characteristics of these seizures on electroencephalography were not altered. As CD2AP is expressed in brain-adjacent endothelial cells, we hypothesized that the shorter latency to seizures without detectably different seizure characteristics may be due to increased penetration of PTZ related to compromised blood-brain barrier integrity. Using sodium fluorescein extravasation, we found that CD2AP(-/-) mice had reduced blood-brain barrier integrity. Neither seizure severity nor blood-brain barrier integrity was correlated with nephrotic syndrome, indicating that these effects are dissociable from the systemic illness associated with CD2AP deficiency. Confirming this dissociation, wild-type mice with induced nephrotic syndrome maintained an intact blood-brain barrier. Taken together, our results support a role of CD2AP in mediating blood-brain barrier integrity and suggest that cerebrovascular roles of CD2AP could contribute to its effects on Alzheimer's disease risk.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/genética , Barreira Hematoencefálica/metabolismo , Proteínas do Citoesqueleto/genética , Doença de Alzheimer/genética , Animais , Ansiedade/genética , Ansiedade/metabolismo , Eletroencefalografia , Feminino , Deleção de Genes , Masculino , Camundongos , Camundongos Knockout , Atividade Motora/genética , Síndrome Nefrótica/genética , Síndrome Nefrótica/metabolismo
11.
NPJ Prim Care Respir Med ; 25: 15020, 2015 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-26028347

RESUMO

BACKGROUND: Extending palliative care to those with advanced non-malignant disease is advocated, but the implications in specific conditions are poorly understood. AIMS: We piloted a novel nurse-led intervention, HELPing older people with very severe chronic obstructive pulmonary disease (HELP-COPD), undertaken 4 weeks after discharge from hospital, which sought to identify and address the holistic care needs of people with severe COPD. METHODS: This 6-month mixed-method feasibility pilot trial randomised (ratio 3:1) patients to HELP-COPD or usual care. We assessed the feasibility of using validated questionnaires as outcome measures and analysed the needs/actions recorded in the HELP-COPD records. Semi-structured interviews with a purposive sample of patients, carers and professionals explored the perceptions of HELP-COPD. Verbatim transcriptions and field notes were analysed using Normalisation Process Theory as a framework. RESULTS: We randomised 32 patients (24 to HELP-COPD); 19 completed the study (death=3, ill-health=4, declined=6). The HELP-COPD record noted a mean of 1.6 actions/assessment, mostly provision of information or self-help actions: only five referrals were made. Most patients were positive about HELP-COPD, discussing their concerns and coping strategies in all domains, but the questionnaires were burdensome for some patients. Adaptation to their slowly progressive disability and a strong preference to rely on family support was reflected in limited acceptance of formal services. Professionals perceived HELP-COPD as addressing an important aspect of care, although timing overlapped with discharge planning. CONCLUSIONS: The HELP-COPD intervention was well received by patients and the concept resonated with professionals, although delivery post discharge overlapped with existing services. Integration of brief holistic care assessments in the routine primary care management of COPD may be more appropriate.


Assuntos
Doença Pulmonar Obstrutiva Crônica/terapia , Adaptação Psicológica , Estudos de Viabilidade , Saúde Holística , Humanos , Avaliação em Enfermagem , Projetos Piloto , Doença Pulmonar Obstrutiva Crônica/psicologia
12.
Sci Transl Med ; 7(289): 289ra86, 2015 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-26019222

RESUMO

Glioma is the most common malignant primary brain tumor. Its rapid growth is aided by tumor-mediated glutamate release, creating peritumoral excitotoxic cell death and vacating space for tumor expansion. Glioma glutamate release may also be responsible for seizures, which complicate the clinical course for many patients and are often the presenting symptom. A hypothesized glutamate release pathway is the cystine/glutamate transporter System xc (-) (SXC), responsible for the cellular synthesis of glutathione (GSH). However, the relationship of SXC-mediated glutamate release, seizures, and tumor growth remains unclear. Probing expression of SLC7A11/xCT, the catalytic subunit of SXC, in patient and mouse-propagated tissues, we found that ~50% of patient tumors have elevated SLC7A11 expression. Compared with tumors lacking this transporter, in vivo propagated and intracranially implanted SLC7A11-expressing tumors grew faster, produced pronounced peritumoral glutamate excitotoxicity, induced seizures, and shortened overall survival. In agreement with animal data, increased SLC7A11 expression predicted shorter patient survival according to genomic data in the REMBRANDT (National Institutes of Health Repository for Molecular Brain Neoplasia Data) database. In a clinical pilot study, we used magnetic resonance spectroscopy to determine SXC-mediated glutamate release by measuring acute changes in glutamate after administration of the U.S. Food and Drug Administration-approved SXC inhibitor, sulfasalazine (SAS). In nine glioma patients with biopsy-confirmed SXC expression, we found that expression positively correlates with glutamate release, which is acutely inhibited with oral SAS. These data suggest that SXC is the major pathway for glutamate release from gliomas and that SLC7A11 expression predicts accelerated growth and tumor-associated seizures.


Assuntos
Sistema y+ de Transporte de Aminoácidos/metabolismo , Glioma/complicações , Glioma/metabolismo , Convulsões/complicações , Convulsões/metabolismo , Edema/patologia , Genômica , Glioma/classificação , Glutamatos/metabolismo , Humanos , Neurônios/efeitos dos fármacos , Neurônios/patologia , Neurotoxinas/toxicidade , Análise de Sobrevida
13.
J Neurosci ; 35(15): 6221-30, 2015 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-25878292

RESUMO

Neuronal hyperexcitability occurs early in the pathogenesis of Alzheimer's disease (AD) and contributes to network dysfunction in AD patients. In other disorders with neuronal hyperexcitability, dysfunction in the dendrites often contributes, but dendritic excitability has not been directly examined in AD models. We used dendritic patch-clamp recordings to measure dendritic excitability in the CA1 region of the hippocampus. We found that dendrites, more so than somata, of hippocampal neurons were hyperexcitable in mice overexpressing Aß. This dendritic hyperexcitability was associated with depletion of Kv4.2, a dendritic potassium channel important for regulating dendritic excitability and synaptic plasticity. The antiepileptic drug, levetiracetam, blocked Kv4.2 depletion. Tau was required, as crossing with tau knock-out mice also prevented both Kv4.2 depletion and dendritic hyperexcitability. Dendritic hyperexcitability induced by Kv4.2 deficiency exacerbated behavioral deficits and increased epileptiform activity in hAPP mice. We conclude that increased dendritic excitability, associated with changes in dendritic ion channels including Kv4.2, may contribute to neuronal dysfunction in early stages AD.


Assuntos
Doença de Alzheimer/patologia , Região CA1 Hipocampal/patologia , Dendritos/fisiologia , Neurônios/patologia , Canais de Potássio Shal/deficiência , Proteínas tau/deficiência , Potenciais de Ação/efeitos dos fármacos , Potenciais de Ação/genética , Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/genética , Peptídeos beta-Amiloides/farmacologia , Precursor de Proteína beta-Amiloide/genética , Animais , Ondas Encefálicas/efeitos dos fármacos , Ondas Encefálicas/genética , Região CA1 Hipocampal/efeitos dos fármacos , Feminino , Regulação da Expressão Gênica/efeitos dos fármacos , Regulação da Expressão Gênica/genética , Humanos , Técnicas In Vitro , Levetiracetam , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Mutação/genética , Neurônios/efeitos dos fármacos , Nootrópicos/farmacologia , Piracetam/análogos & derivados , Piracetam/farmacologia , Canais de Potássio Shal/genética , Proteínas tau/genética
14.
J Pain Symptom Manage ; 50(2): 216-24, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25828558

RESUMO

CONTEXT: Quality care for people living with life-limiting illnesses is a global priority. A detailed understanding of the varied experiences of people living and dying with different conditions and their family and professional caregivers should help policymakers and clinicians design and deliver more appropriate and person-centered care. OBJECTIVES: To understand how patients with different advanced conditions and their family and professional caregivers perceive their deteriorating health and the services they need. METHODS: We used a narrative framework to synthesize eight methodologically comparable, longitudinal, and multiperspective interview studies. We compared the end-of-life experiences of people dying from cancer (lung, glioma, and colorectal cancer), organ failure (heart failure, chronic obstructive pulmonary disease, and liver failure), and physical frailty and those of their family and professional caregivers in socioeconomically and ethnically diverse populations in Scotland. RESULTS: The data set comprised 828 in-depth interviews with 156 patients, 114 family caregivers, and 170 health professionals. Narratives about cancer typically had a clear beginning, middle, and an anticipated end. Cancer patients gave a well-rehearsed account of their illness, hoping for recovery alongside fear of dying. In contrast, people with organ failure and their family caregivers struggled to pinpoint when their illness began, or to speak openly about death, hoping instead to avoid further deterioration. Frail older people tended to be frustrated by their progressive loss of independence, fearing dementia or nursing home admission more than dying. CONCLUSION: These contrasting illness narratives affect and shape the experiences, thoughts, and fears of patients and their carers in the last months of life. Palliative care offered by generalists or specialists should be provided more flexibly and equitably, responding to the varied concerns and needs of people with different advanced conditions.


Assuntos
Atitude do Pessoal de Saúde , Cuidadores/psicologia , Família/psicologia , Cuidados Paliativos/psicologia , Assistência Terminal/psicologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias Colorretais/terapia , Idoso Fragilizado/psicologia , Idoso Fragilizado/estatística & dados numéricos , Glioma/terapia , Objetivos , Pessoal de Saúde/psicologia , Insuficiência Cardíaca/terapia , Humanos , Entrevistas como Assunto , Falência Hepática/terapia , Estudos Longitudinais , Neoplasias Pulmonares/terapia , Pessoa de Meia-Idade , Cuidados Paliativos/métodos , Doença Pulmonar Obstrutiva Crônica/terapia , Escócia , Assistência Terminal/métodos , Adulto Jovem
15.
Ann Clin Transl Neurol ; 2(4): 401-16, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25909085

RESUMO

OBJECTIVE: Temporal lobe epilepsy (TLE) patients exhibit signs of memory impairments even when seizures are pharmacologically controlled. Surprisingly, the underlying molecular mechanisms involved in TLE-associated memory impairments remain elusive. Memory consolidation requires epigenetic transcriptional regulation of genes in the hippocampus; therefore, we aimed to determine how epigenetic DNA methylation mechanisms affect learning-induced transcription of memory-permissive genes in the epileptic hippocampus. METHODS: Using the kainate rodent model of TLE and focusing on the brain-derived neurotrophic factor (Bdnf) gene as a candidate of DNA methylation-mediated transcription, we analyzed DNA methylation levels in epileptic rats following learning. After detection of aberrant DNA methylation at the Bdnf gene, we investigated functional effects of altered DNA methylation on hippocampus-dependent memory formation in our TLE rodent model. RESULTS: We found that behaviorally driven BdnfDNA methylation was associated with hippocampus-dependent memory deficits. Bisulfite sequencing revealed that decreased BdnfDNA methylation levels strongly correlated with abnormally high levels of BdnfmRNA in the epileptic hippocampus during memory consolidation. Methyl supplementation via methionine (Met) increased BdnfDNA methylation and reduced BdnfmRNA levels in the epileptic hippocampus during memory consolidation. Met administration reduced interictal spike activity, increased theta rhythm power, and reversed memory deficits in epileptic animals. The rescue effect of Met treatment on learning-induced BdnfDNA methylation, Bdnf gene expression, and hippocampus-dependent memory, were attenuated by DNA methyltransferase blockade. INTERPRETATION: Our findings suggest that manipulation of DNA methylation in the epileptic hippocampus should be considered as a viable treatment option to ameliorate memory impairments associated with TLE.

16.
J Neurosci ; 35(8): 3330-45, 2015 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-25716834

RESUMO

Epilepsy is one of the most common chronic neurologic diseases, yet approximately one-third of affected patients do not respond to anticonvulsive drugs that target neurons or neuronal circuits. Reactive astrocytes are commonly found in putative epileptic foci and have been hypothesized to be disease contributors because they lose essential homeostatic capabilities. However, since brain pathology induces astrocytes to become reactive, it is difficult to distinguish whether astrogliosis is a cause or a consequence of epileptogenesis. We now present a mouse model of genetically induced, widespread chronic astrogliosis after conditional deletion of ß1-integrin (Itgß1). In these mice, astrogliosis occurs in the absence of other pathologies and without BBB breach or significant inflammation. Electroencephalography with simultaneous video recording revealed that these mice develop spontaneous seizures during the first six postnatal weeks of life and brain slices show neuronal hyperexcitability. This was not observed in mice with neuronal-targeted ß1-integrin deletion, supporting the hypothesis that astrogliosis is sufficient to induce epileptic seizures. Whole-cell patch-clamp recordings from astrocytes further suggest that the heightened excitability was associated with impaired astrocytic glutamate uptake. Moreover, the relative expression of the cation-chloride cotransporters (CCC) NKCC1 (Slc12a2) and KCC2 (Slc12a5), which are responsible for establishing the neuronal Cl(-) gradient that governs GABAergic inhibition were altered and the NKCC1 inhibitor bumetanide eliminated seizures in a subgroup of mice. These data suggest that a shift in the relative expression of neuronal NKCC1 and KCC2, similar to that observed in immature neurons during development, may contribute to astrogliosis-associated seizures.


Assuntos
Astrócitos/metabolismo , Gliose/metabolismo , Integrina beta1/metabolismo , Convulsões/metabolismo , Potenciais de Ação , Animais , Astrócitos/fisiologia , Barreira Hematoencefálica/metabolismo , Células Cultivadas , Gliose/fisiopatologia , Ácido Glutâmico/metabolismo , Integrina beta1/genética , Camundongos , Neurônios/metabolismo , Neurônios/fisiologia , Convulsões/etiologia , Convulsões/patologia , Convulsões/fisiopatologia , Membro 2 da Família 12 de Carreador de Soluto/genética , Membro 2 da Família 12 de Carreador de Soluto/metabolismo , Simportadores/genética , Simportadores/metabolismo , Cotransportadores de K e Cl-
17.
J Innov Health Inform ; 22(4): 409-25, 2015 Dec 24.
Artigo em Inglês | MEDLINE | ID: mdl-26855275

RESUMO

BACKGROUND: Systematic reviews have suggested that time spent on computer-related tasks increases consultation length. However, these reviews pre-date the current ubiquitous use of computers in U.K. general practice. OBJECTIVE: As part of a U.K. national study of the influence of information technology (IT) on the interaction between patients and healthcare professionals during consultations, we explored how IT functions affected time allocation and styles of computer use during general practitioner (GP) consultations. METHODS: We drew on multichannel video recording of consultations and measured consultation phases and the duration of computer-related tasks. We related measures of actual time to GP's interpretation of computer use elicited in qualitative interviews. RESULTS: Our sample included recordings of 112 consultations from 6 GPs in three practices. The computer was used for about one-third of the greater consultation. However, its use was concentrated pre- and post- the patient consultation. The workflow of consultation was exemplified through six computer use cases. Most functionality was accepted and accommodated within the consultation, though disruptive and time-consuming tasks were generally delegated to administrative staff. Recognised styles of computer use (minimal, block and conversational) were apparent, but applied very flexibly by GPs according to the nature of the consultation. CONCLUSIONS: In contrast to earlier reports, contemporary computer use does not appear to have lengthened consultations. GPs adopted different styles of computer use in different consultations, challenging classifications that seek to stereotype GP computer use. Designing systems that support this versatility require an understanding of the fluid application of computer use within consultation structure.


Assuntos
Registros Eletrônicos de Saúde , Clínicos Gerais , Relações Médico-Paciente , Padrões de Prática Médica , Interface Usuário-Computador , Comunicação , Humanos , Visita a Consultório Médico , Pesquisa Qualitativa , Fatores de Tempo , Gravação em Vídeo/métodos
18.
Glia ; 63(1): 23-36, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25066727

RESUMO

Seizures frequently accompany gliomas and often escalate to peritumoral epilepsy. Previous work revealed the importance of tumor-derived excitatory glutamate (Glu) release mediated by the cystine-glutamate transporter (SXC) in epileptogenesis. We now show a novel contribution of GABAergic disinhibition to disease pathophysiology. In a validated mouse glioma model, we found that peritumoral parvalbumin-positive GABAergic inhibitory interneurons are significantly reduced, corresponding with deficits in spontaneous and evoked inhibitory neurotransmission. Most remaining peritumoral neurons exhibit elevated intracellular Cl(-) concentration ([Cl(-) ]i ) and consequently depolarizing, excitatory gamma-aminobutyric acid (GABA) responses. In these neurons, the plasmalemmal expression of KCC2, which establishes the low [Cl(-) ]i required for GABAA R-mediated inhibition, is significantly decreased. Interestingly, reductions in inhibition are independent of Glu release, but the presence of both decreased inhibition and decreased SXC expression is required for epileptogenesis. We suggest GABAergic disinhibition renders peritumoral neuronal networks hyper-excitable and susceptible to seizures triggered by excitatory stimuli, and propose KCC2 as a therapeutic target.


Assuntos
Neoplasias Encefálicas/metabolismo , Epilepsia/metabolismo , Glioma/metabolismo , Receptores de GABA-A/metabolismo , Simportadores/metabolismo , Ácido gama-Aminobutírico/metabolismo , Animais , Neoplasias Encefálicas/complicações , Epilepsia/etiologia , Feminino , Glioma/complicações , Interneurônios/metabolismo , Masculino , Camundongos , Neurônios/metabolismo , Transmissão Sináptica/fisiologia , Cotransportadores de K e Cl-
19.
Epilepsia ; 55(12): e139-42, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25385326

RESUMO

Studies have demonstrated that the membrane attack complex (MAC) of complement can evoke seizures when injected directly into rodent brain. In the course of studies that examine the role of complement in the development of experimental cerebral malaria (ECM), we observed fewer seizures in mice deficient in C5, a component required for MAC formation. To determine if the MAC contributed to the tonic-clonic seizures characteristic of ECM, we performed long-term video-electroencephalography (EEG) on C5(-/-) mice with Plasmodium berghei ANKA-induced cerebral malaria and observed significantly reduced spike and seizure frequency compared to wild-type mice. Our data suggest a role for the MAC in malaria-induced seizures and that inhibition of the terminal complement pathway may reduce seizures and seizure-related neurocognitive deficits.


Assuntos
Complemento C5/deficiência , Malária Cerebral/complicações , Convulsões , Animais , Modelos Animais de Doenças , Eletroencefalografia , Malária Cerebral/genética , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Plasmodium berghei/patogenicidade , Convulsões/etiologia , Convulsões/genética , Convulsões/prevenção & controle
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