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1.
Cell ; 178(6): 1362-1374.e16, 2019 09 05.
Artigo em Inglês | MEDLINE | ID: mdl-31447178

RESUMO

TRPA1 is a chemosensory ion channel that functions as a sentinel for structurally diverse electrophilic irritants. Channel activation occurs through an unusual mechanism involving covalent modification of cysteine residues clustered within an amino-terminal cytoplasmic domain. Here, we describe a peptidergic scorpion toxin (WaTx) that activates TRPA1 by penetrating the plasma membrane to access the same intracellular site modified by reactive electrophiles. WaTx stabilizes TRPA1 in a biophysically distinct active state characterized by prolonged channel openings and low Ca2+ permeability. Consequently, WaTx elicits acute pain and pain hypersensitivity but fails to trigger efferent release of neuropeptides and neurogenic inflammation typically produced by noxious electrophiles. These findings provide a striking example of convergent evolution whereby chemically disparate animal- and plant-derived irritants target the same key allosteric regulatory site to differentially modulate channel activity. WaTx is a unique pharmacological probe for dissecting TRPA1 function and its contribution to acute and persistent pain.


Assuntos
Venenos de Escorpião/farmacologia , Canal de Cátion TRPA1/metabolismo , Animais , Células HEK293 , Humanos , Camundongos Endogâmicos C57BL , Ratos Sprague-Dawley , Escorpiões/metabolismo
2.
Nature ; 599(7883): 152-157, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34646016

RESUMO

Molecular switch proteins whose cycling between states is controlled by opposing regulators1,2 are central to biological signal transduction. As switch proteins function within highly connected interaction networks3, the fundamental question arises of how functional specificity is achieved when different processes share common regulators. Here we show that functional specificity of the small GTPase switch protein Gsp1 in Saccharomyces cerevisiae (the homologue of the human protein RAN)4 is linked to differential sensitivity of biological processes to different kinetics of the Gsp1 (RAN) switch cycle. We make 55 targeted point mutations to individual protein interaction interfaces of Gsp1 (RAN) and show through quantitative genetic5 and physical interaction mapping that Gsp1 (RAN) interface perturbations have widespread cellular consequences. Contrary to expectation, the cellular effects of the interface mutations group by their biophysical effects on kinetic parameters of the GTPase switch cycle and not by the targeted interfaces. Instead, we show that interface mutations allosterically tune the GTPase cycle kinetics. These results suggest a model in which protein partner binding, or post-translational modifications at distal sites, could act as allosteric regulators of GTPase switching. Similar mechanisms may underlie regulation by other GTPases, and other biological switches. Furthermore, our integrative platform to determine the quantitative consequences of molecular perturbations may help to explain the effects of disease mutations that target central molecular switches.


Assuntos
Regulação Alostérica/genética , Proteínas Monoméricas de Ligação ao GTP/genética , Proteínas Monoméricas de Ligação ao GTP/metabolismo , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Mutação Puntual , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae , Sítios de Ligação/genética , Domínio Catalítico/genética , Proteínas Ativadoras de GTPase/metabolismo , Fatores de Troca do Nucleotídeo Guanina/metabolismo , Guanosina Trifosfato/metabolismo , Cinética , Ligação Proteica/genética , Saccharomyces cerevisiae/enzimologia , Saccharomyces cerevisiae/genética
3.
Alzheimer Dis Assoc Disord ; 37(1): 88-91, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-35969849

RESUMO

Posterior cortical atrophy (PCA) is a clinico-radiological syndrome characterised by progressive decline in visual processing and other posterior cognitive functions, relatively preserved memory and language in the early stages, and atrophy of posterior brain regions. Often considered a "visual variant" of Alzheimer's disease, a number of other pathological substrates are recognised. Dementia with Lewy Bodies is the second most common neurodegenerative dementia and there is increasing recognition of presentations with little or no parkinsonism, highlighting significant under-recognition of this condition. To complicate matters, some patients with PCA exhibit additional features consistent with other neurodegenerative conditions. We present a series of three such patients presenting with features satisfying the recent consensus criteria for "PCA-Plus (DLB)". We review the current classification of PCA and highlight the importance of deep clinico-radiological phenotyping in neurodegenerative disease to guide targeted interventions and establish future trial-ready cohorts.


Assuntos
Doença de Alzheimer , Doença por Corpos de Lewy , Doenças Neurodegenerativas , Humanos , Doença por Corpos de Lewy/diagnóstico , Árvores , Doença de Alzheimer/patologia , Atrofia/complicações
4.
Cerebellum ; 21(2): 280-296, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34228323

RESUMO

Inherited ataxias are a heterogenous group of neurodegenerative disorders characterised by progressive impairment of balance and coordination, typically leading to permanent and progressive disability. Diagnosis and management of these disorders incurs a range of direct and indirect financial costs. The aim of this study was to collect individual ataxia-related healthcare resources in a large cohort of individuals with different subtypes of inherited ataxia and calculate the associated cost of illness in the Republic of Ireland. One hundred twenty-nine respondents completed a cross-sectional study on healthcare resource utilisation for progressive ataxia in Ireland. Costs were calculated using a prevalence-based approach and bottom-up methodology. The COI for inherited ataxia in 2016 was €59,993 per person per year. Results were similar between participants with Friedreich's ataxia (FRDA, n = 56), non-FRDA (n = 18) and those with undetermined ataxia (n = 55). Indirect costs, based on productivity losses by participants or caregivers, accounted for 52% of the cost of illness. Inherited ataxia is associated with significant health and social care costs. Further funding for inherited ataxia to ease the financial burden on patients, caregivers and healthcare system and improve standards of care compliance is warranted.


Assuntos
Ataxia Cerebelar , Ataxia de Friedreich , Degenerações Espinocerebelares , Estudos Transversais , Ataxia de Friedreich/epidemiologia , Ataxia de Friedreich/genética , Ataxia de Friedreich/terapia , Humanos , Irlanda/epidemiologia , Degenerações Espinocerebelares/diagnóstico , Degenerações Espinocerebelares/epidemiologia , Degenerações Espinocerebelares/genética
5.
Mov Disord ; 34(8): 1174-1183, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31283854

RESUMO

OBJECTIVE: The objective of this study was to identify clinical predictors of motor complications (dyskinesia and motor fluctuations) of levodopa in a prospectively recruited PD cohort using longitudinal analysis. METHODS: An inception cohort (Oxford Discovery) of 734 patients was followed to a maximum of 10 years from diagnosis using a discrete-time survival analysis. A subset analysis was used to validate an online dyskinesia-risk calculator developed from the results of the Stalevo Reduction in Dyskinesia Evaluation PD trial. RESULTS: A total of 186 cases of dyskinesia and 254 cases of motor fluctuations were observed. Dyskinesia incidence increased with time (risk per 100 participants [95% confidence interval] 13 [11-16] <3.5 years, 16 [13-21] 3.5-5.0 years, 19 [14-26] 5-6.5 years, and 23 [16-33] >6.5 years from diagnosis). Motor complication predictors were grouped as medication predictors, disease predictors and patient predictors. Baseline nonmotor feature severity, low mood, anxiety, and age at symptom onset were associated with motor complications among a number of previously identified predictors. Replication of the Stalevo Reduction in Dyskinesia Evaluation PD calculator was reasonable with the area under the curve for dyskinesia risk score as a predictor of dyskinesia being 0.68 (95% confidence interval, 0.55-0.81). CONCLUSIONS: This study quantifies risk of motor complications, finds consistent predictors, and demonstrates the novel finding that nonmotor features of PD, particularly low mood and anxiety, are significant risk factors for motor complications. Further validation of dyskinesia risk scores are required as well as evidence to determine if the routine use of such scores can be clinically valuable in enhancing patient care and quality of life. © 2019 The Authors. Movement Disorders published by Wiley Periodicals, Inc. on behalf of International Parkinson and Movement Disorder Society.


Assuntos
Antiparkinsonianos/efeitos adversos , Ansiedade/epidemiologia , Depressão/epidemiologia , Discinesia Induzida por Medicamentos/epidemiologia , Levodopa/efeitos adversos , Doença de Parkinson/tratamento farmacológico , Adulto , Idade de Início , Idoso , Idoso de 80 Anos ou mais , Estudos de Coortes , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/epidemiologia , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/etiologia , Discinesia Induzida por Medicamentos/etiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Doença de Parkinson/epidemiologia , Doença de Parkinson/fisiopatologia , Modelos de Riscos Proporcionais , Estudos Prospectivos , Medição de Risco , Índice de Gravidade de Doença
7.
Proc Natl Acad Sci U S A ; 112(47): E6436-45, 2015 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-26554011

RESUMO

Actin filament networks assemble on cellular membranes in response to signals that locally activate neural Wiskott-Aldrich-syndrome protein (N-WASP) and the Arp2/3 complex. An inactive conformation of N-WASP is stabilized by intramolecular contacts between the GTPase binding domain (GBD) and the C helix of the verprolin-homology, connector-helix, acidic motif (VCA) segment. Multiple SH3 domain-containing adapter proteins can bind and possibly activate N-WASP, but it remains unclear how such binding events relieve autoinhibition to unmask the VCA segment and activate the Arp2/3 complex. Here, we have used purified components to reconstitute a signaling cascade driven by membrane-localized Src homology 3 (SH3) adapters and N-WASP, resulting in the assembly of dynamic actin networks. Among six SH3 adapters tested, Nck was the most potent activator of N-WASP-driven actin assembly. We identify within Nck a previously unrecognized activation motif in a linker between the first two SH3 domains. This linker sequence, reminiscent of bacterial virulence factors, directly engages the N-WASP GBD and competes with VCA binding. Our results suggest that animals, like pathogenic bacteria, have evolved peptide motifs that allosterically activate N-WASP, leading to localized actin nucleation on cellular membranes.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/química , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Proteínas Oncogênicas/química , Proteínas Oncogênicas/metabolismo , Proteína Neuronal da Síndrome de Wiskott-Aldrich/metabolismo , Domínios de Homologia de src , Actinas/metabolismo , Regulação Alostérica , Motivos de Aminoácidos , Sequência de Aminoácidos , Animais , Humanos , Interações Hidrofóbicas e Hidrofílicas , Espectroscopia de Ressonância Magnética , Proteínas de Membrana/metabolismo , Camundongos , Dados de Sequência Molecular , Proteínas Mutantes/química , Ligação Proteica , Estrutura Secundária de Proteína , Ratos , Relação Estrutura-Atividade
9.
RSC Chem Biol ; 5(3): 209-215, 2024 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-38456036

RESUMO

PHD fingers are a type of chromatin reader that primarily recognize chromatin as a function of lysine methylation state. Dysregulated PHD fingers are implicated in various human diseases, including acute myeloid leukemia. Targeting PHD fingers with small molecules is considered challenging as their histone tail binding pockets are often shallow and surface-exposed. The KDM5A PHD1 finger regulates the catalytic activity of KDM5A, an epigenetic enzyme often misregulated in cancers. To identify ligands that disrupt the PHD1-histone peptide interaction, we conducted a high-throughput screen and validated hits by orthogonal methods. We further elucidated structure-activity relationships in two classes of compounds to identify features important for binding. Our investigation offers a starting point for further optimization of small molecule PHD1 ligands.

10.
JAMA Neurol ; 81(5): 525-533, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38497971

RESUMO

Importance: Rapid and accurate diagnosis of autoimmune encephalitis encourages prompt initiation of immunotherapy toward improved patient outcomes. However, clinical features alone may not sufficiently narrow the differential diagnosis, and awaiting autoantibody results can delay immunotherapy. Objective: To identify simple magnetic resonance imaging (MRI) characteristics that accurately distinguish 2 common forms of autoimmune encephalitis, LGI1- and CASPR2-antibody encephalitis (LGI1/CASPR2-Ab-E), from 2 major differential diagnoses, viral encephalitis (VE) and Creutzfeldt-Jakob disease (CJD). Design, Setting, and Participants: This cross-sectional study involved a retrospective, blinded analysis of the first available brain MRIs (taken 2000-2022) from 192 patients at Oxford University Hospitals in the UK and Mayo Clinic in the US. These patients had LGI1/CASPR2-Ab-E, VE, or CJD as evaluated by 2 neuroradiologists (discovery cohort; n = 87); findings were validated in an independent cohort by 3 neurologists (n = 105). Groups were statistically compared with contingency tables. Data were analyzed in 2023. Main Outcomes and Measures: MRI findings including T2 or fluid-attenuated inversion recovery (FLAIR) hyperintensities, swelling or volume loss, presence of gadolinium contrast enhancement, and diffusion-weighted imaging changes. Correlations with clinical features. Results: Among 192 participants with MRIs reviewed, 71 were female (37%) and 121 were male (63%); the median age was 66 years (range, 19-92 years). By comparison with VE and CJD, in LGI1/CASPR2-Ab-E, T2 and/or FLAIR hyperintensities were less likely to extend outside the temporal lobe (3/42 patients [7%] vs 17/18 patients [94%] with VE; P < .001, and 3/4 patients [75%] with CJD; P = .005), less frequently exhibited swelling (12/55 [22%] with LGI1/CASPR2-Ab-E vs 13/22 [59%] with VE; P = .003), and showed no diffusion restriction (0 patients vs 16/22 [73%] with VE and 8/10 [80%] with CJD; both P < .001) and rare contrast enhancement (1/20 [5%] vs 7/17 [41%] with VE; P = .01). These findings were validated in an independent cohort and generated an area under the curve of 0.97, sensitivity of 90%, and specificity of 95% among cases with T2/FLAIR hyperintensity in the hippocampus and/or amygdala. Conclusions and Relevance: In this study, T2 and/or FLAIR hyperintensities confined to the temporal lobes, without diffusion restriction or contrast enhancement, robustly distinguished LGI1/CASPR2-Ab-E from key differential diagnoses. These observations should assist clinical decision-making toward expediting immunotherapy. Their generalizability to other forms of autoimmune encephalitis and VE should be examined in future studies.


Assuntos
Autoanticorpos , Encefalite , Peptídeos e Proteínas de Sinalização Intracelular , Imageamento por Ressonância Magnética , Proteínas de Membrana , Proteínas do Tecido Nervoso , Humanos , Masculino , Feminino , Idoso , Peptídeos e Proteínas de Sinalização Intracelular/imunologia , Pessoa de Meia-Idade , Imageamento por Ressonância Magnética/métodos , Estudos Transversais , Autoanticorpos/imunologia , Encefalite/diagnóstico por imagem , Encefalite/imunologia , Encefalite/patologia , Estudos Retrospectivos , Proteínas do Tecido Nervoso/imunologia , Proteínas de Membrana/imunologia , Adulto , Idoso de 80 Anos ou mais , Síndrome de Creutzfeldt-Jakob/diagnóstico por imagem , Síndrome de Creutzfeldt-Jakob/imunologia , Síndrome de Creutzfeldt-Jakob/patologia , Diagnóstico Diferencial , Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Doença de Hashimoto/diagnóstico por imagem , Doença de Hashimoto/imunologia , Adulto Jovem
11.
Anesthesiology ; 119(5): 1120-36, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23748856

RESUMO

BACKGROUND: Mild brain hypothermia (32°-34°C) after human neonatal asphyxia improves neurodevelopmental outcomes. Astrocytes but not neurons have pyruvate carboxylase and an acetate uptake transporter. C nuclear magnetic resonance spectroscopy of rodent brain extracts after administering [1-C]glucose and [1,2-C]acetate can distinguish metabolic differences between glia and neurons, and tricarboxylic acid cycle entry via pyruvate dehydrogenase and pyruvate carboxylase. METHODS: Neonatal rat cerebrocortical slices receiving a C-acetate/glucose mixture underwent a 45-min asphyxia simulation via oxygen-glucose-deprivation followed by 6 h of recovery. Protocols in three groups of N=3 experiments were identical except for temperature management. The three temperature groups were: normothermia (37°C), hypothermia (32°C for 3.75 h beginning at oxygen--glucose deprivation start), and delayed hypothermia (32°C for 3.75 h, beginning 15 min after oxygen-glucose deprivation start). Multivariate analysis of nuclear magnetic resonance metabolite quantifications included principal component analyses and the L1-penalized regularized regression algorithm known as the least absolute shrinkage and selection operator. RESULTS: The most significant metabolite difference (P<0.0056) was [2-C]glutamine's higher final/control ratio for the hypothermia group (1.75±0.12) compared with ratios for the delayed (1.12±0.12) and normothermia group (0.94±0.06), implying a higher pyruvate carboxylase/pyruvate dehydrogenase ratio for glutamine formation. Least Absolute Shrinkage and Selection Operator found the most important metabolites associated with adenosine triphosphate preservation: [3,4-C]glutamate-produced via pyruvate dehydrogenase entry, [2-C]taurine-an important osmolyte and antioxidant, and phosphocreatine. Final principal component analyses scores plots suggested separate cluster formation for the hypothermia group, but with insufficient data for statistical significance. CONCLUSIONS: Starting mild hypothermia simultaneously with oxygen-glucose deprivation, compared with delayed starting or no hypothermia, has higher pyruvate carboxylase throughput, suggesting that better glial integrity is one important neuroprotection mechanism of earlier hypothermia.


Assuntos
Córtex Cerebral/fisiologia , Glucose/deficiência , Hipotermia Induzida , Hipóxia Encefálica/metabolismo , Acetatos/metabolismo , Difosfato de Adenosina/metabolismo , Trifosfato de Adenosina/metabolismo , Animais , Biomarcadores/metabolismo , Temperatura Corporal , Química Encefálica , Feminino , Proteína Glial Fibrilar Ácida/metabolismo , Hipóxia Encefálica/terapia , Técnicas In Vitro , Espectroscopia de Ressonância Magnética , Masculino , Metabolômica , Neuroglia/fisiologia , Neurônios/fisiologia , Fosfocreatina/metabolismo , Ratos , Ratos Sprague-Dawley , Análise de Regressão , Ácidos Tricarboxílicos/metabolismo
12.
Pediatr Res ; 74(2): 170-9, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23708689

RESUMO

BACKGROUND: Mild brain hypothermia (31-34 °C) after neonatal hypoxia-ischemia (HI) improves neurodevelopmental outcomes in human and animal neonates. Using an asphyxia model with neonatal mice treated with mild hypothermia after HI, we investigated whether (1)H nuclear magnetic resonance (NMR) metabolomics of brain extracts could suggest biomarkers and distinguish different treatments and outcome groups. METHODS: At postnatal day 7 (P7), CD1 mice underwent right carotid artery occlusion, 30 min of HI (8% oxygen), and 3.5 h of either hypothermia (31 °C) or normothermia (37 °C). Whole brains were frozen immediately after HI, immediately after 3.5 h of hypothermia or normothermia treatments, and 24 h later. Perchloric acid extractions of 36 metabolites were quantified by 900 MHz (1)H NMR spectroscopy. Multivariate analyses included principal component analyses (PCA) and a novel regression algorithm. Histological injury was quantified after HI at 5 d. RESULTS: PCA scores plots separated normothermia/HI animals from hypothermia/HI and control animals, but more data are required for multivariate models to be predictive. Loadings plots identified 11 significant metabolites, whereas the regression algorithm identified 6. Histological injury scores were significantly reduced by hypothermia. CONCLUSION: Different treatment and outcome groups are identifiable by (1)H NMR metabolomics in a neonatal mouse model of mild hypothermia treatment of HI.


Assuntos
Hipotermia Induzida/métodos , Hipóxia-Isquemia Encefálica/metabolismo , Hipóxia-Isquemia Encefálica/terapia , Metaboloma/fisiologia , Animais , Animais Recém-Nascidos , Espectroscopia de Ressonância Magnética , Metaboloma/genética , Metabolômica , Camundongos , Análise de Componente Principal , Análise de Regressão
13.
Nature ; 449(7159): 233-7, 2007 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-17767153

RESUMO

Among the many surprises to arise from studies of prion biology, perhaps the most unexpected is the strain phenomenon whereby a single protein can misfold into structurally distinct, infectious states that cause distinguishable phenotypes. Similarly, proteins can adopt a spectrum of conformations in non-infectious diseases of protein folding; some are toxic and others are well tolerated. However, our understanding of the structural differences underlying prion strains and how these differences alter their physiological impact remains limited. Here we use a combination of solution NMR, amide hydrogen/deuterium (H/D) exchange and mutagenesis to study the structural differences between two strain conformations, termed Sc4 and Sc37 (ref. 5), of the yeast Sup35 prion. We find that these two strains have an overlapping amyloid core spanning most of the Gln/Asn-rich first 40 amino acids that is highly protected from H/D exchange and very sensitive to mutation. These features indicate that the cores are composed of tightly packed beta-sheets possibly resembling 'steric zipper' structures revealed by X-ray crystallography of Sup35-derived peptides. The stable structure is greatly expanded in the Sc37 conformation to encompass the first 70 amino acids, revealing why this strain shows increased fibre stability and decreased ability to undergo chaperone-mediated replication. Our findings establish that prion strains involve large-scale conformational differences and provide a structural basis for understanding a broad range of functional studies, including how conformational changes alter the physiological impact of prion strains.


Assuntos
Príons/química , Príons/classificação , Dobramento de Proteína , Proteínas de Saccharomyces cerevisiae/química , Proteínas de Saccharomyces cerevisiae/classificação , Saccharomyces cerevisiae/química , Saccharomyces cerevisiae/genética , Cristalografia por Raios X , Medição da Troca de Deutério , Mutagênese , Mutação , Ressonância Magnética Nuclear Biomolecular , Fatores de Terminação de Peptídeos , Fenótipo , Príons/genética , Príons/patogenicidade , Estrutura Secundária de Proteína , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/genética
14.
Cochrane Database Syst Rev ; (7): CD009445, 2013 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-23832767

RESUMO

BACKGROUND: Achieving informed consent is a core clinical procedure and is required before any surgical or invasive procedure is undertaken.  However, it is a complex process which requires patients be provided with information which they can understand and retain, opportunity to consider their options, and to be able to express their opinions and ask questions.  There is evidence that at present some patients undergo procedures without informed consent being achieved. OBJECTIVES: To assess the effects on patients, clinicians and the healthcare system of interventions to promote informed consent for patients undergoing surgical and other invasive healthcare treatments and procedures. SEARCH METHODS: We searched the following databases using keywords and medical subject headings: Cochrane Central Register of Controlled Trials (CENTRAL, The Cochrane Library, Issue 5, 2012), MEDLINE (OvidSP) (1950 to July 2011), EMBASE (OvidSP) (1980 to July 2011) and PsycINFO (OvidSP) (1806 to July 2011). We applied no language or date restrictions within the search. We also searched reference lists of included studies. SELECTION CRITERIA: Randomised controlled trials and cluster randomised trials of interventions to promote informed consent for patients undergoing surgical and other invasive healthcare procedures. We considered an intervention to be intended to promote informed consent when information delivery about the procedure was enhanced (either by providing more information or through, for example, using new written materials), or if more opportunity to consider or deliberate on the information was provided. DATA COLLECTION AND ANALYSIS: Two authors assessed the search output independently to identify potentially-relevant studies, selected studies for inclusion, and extracted data. We conducted a narrative synthesis of the included trials, and meta-analyses of outcomes where there were sufficient data. MAIN RESULTS: We included 65 randomised controlled trials from 12 countries involving patients undergoing a variety of procedures in hospitals. Nine thousand and twenty one patients were randomised and entered into these studies. Interventions used various designs and formats but the main data for results were from studies using written materials, audio-visual materials and decision aids. Some interventions were delivered before admission to hospital for the procedure while others were delivered on admission.Only one study attempted to measure the primary outcome, which was informed consent as a unified concept, but this study was at high risk of bias.  More commonly, studies measured secondary outcomes which were individual components of informed consent such as knowledge, anxiety, and satisfaction with the consent process.  Important but less commonly-measured outcomes were deliberation, decisional conflict, uptake of procedures and length of consultation.Meta-analyses showed statistically-significant improvements in knowledge when measured immediately after interventions (SMD 0.53 (95% CI 0.37 to 0.69) I(2) 73%), shortly afterwards (between 24 hours and 14 days) (SMD 0.68 (95% CI 0.42 to 0.93) I(2) 85%) and at a later date (15 days or more) (SMD 0.78 (95% CI 0.50 to 1.06) I(2) 82%). Satisfaction with decision making was also increased (SMD 2.25 (95% CI 1.36 to 3.15) I(2) 99%) and decisional conflict was reduced (SMD -1.80 (95% CI -3.46 to -0.14) I(2) 99%). No statistically-significant differences were found for generalised anxiety (SMD -0.11 (95% CI -0.35 to 0.13) I(2) 82%), anxiety with the consent process (SMD 0.01 (95% CI -0.21 to 0.23) I(2) 70%) and satisfaction with the consent process (SMD 0.12 (95% CI -0.09 to 0.32) I(2) 76%). Consultation length was increased in those studies with continuous data (mean increase 1.66 minutes (95% CI 0.82 to 2.50) I(2) 0%) and in the one study with non-parametric data (control 8.0 minutes versus intervention 11.9 minutes, interquartile range (IQR) of 4 to 11.9 and 7.2 to 15.0 respectively). There were limited data for other outcomes.In general, sensitivity analyses removing studies at high risk of bias made little difference to the overall results.  AUTHORS' CONCLUSIONS: Informed consent is an important ethical and practical part of patient care.  We have identified efforts by researchers to investigate interventions which seek to improve information delivery and consideration of information to enhance informed consent.  The interventions used consistently improve patient knowledge, an important prerequisite for informed consent.  This is encouraging and these measures could be widely employed although we are not able to say with confidence which types of interventions are preferable. Our results should be interpreted with caution due to the high levels of heterogeneity associated with many of the main analyses although we believe there is broad evidence of beneficial outcomes for patients with the pragmatic application of interventions. Only one study attempted to measure informed consent as a unified concept.


Assuntos
Consentimento Livre e Esclarecido/estatística & dados numéricos , Procedimentos Cirúrgicos Operatórios , Técnicas de Apoio para a Decisão , Endoscopia , Humanos , Folhetos , Educação de Pacientes como Assunto/métodos , Ensaios Clínicos Controlados Aleatórios como Assunto , Materiais de Ensino
15.
ACS Chem Biol ; 18(9): 1915-1925, 2023 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-33621062

RESUMO

PHD reader domains are chromatin binding modules often responsible for the recruitment of large protein complexes that contain histone modifying enzymes, chromatin remodelers, and DNA repair machinery. A majority of PHD domains recognize N-terminal residues of histone H3 and are sensitive to the methylation state of Lys4 in histone H3 (H3K4). Histone demethylase KDM5A, an epigenetic eraser enzyme that contains three PHD domains, is often overexpressed in various cancers, and its demethylation activity is allosterically enhanced when its PHD1 domain is bound to the H3 tail. The allosteric regulatory function of PHD1 expands roles of reader domains, suggesting unique features of this chromatin interacting module. Our previous studies determined the H3 binding site of PHD1, although it remains unclear how the H3 tail interacts with the N-terminal residues of PHD1 and how PHD1 discriminates against H3 tails with varying degrees of H3K4 methylation. Here, we have determined the solution structure of apo and H3 bound PHD1. We observe conformational changes occurring in PHD1 in order to accommodate H3, which interestingly binds in a helical conformation. We also observe differential interactions of binding residues with differently methylated H3K4 peptides (me0, me1, me2, or me3), providing a rationale for PHD1's preference for lower methylation states of H3K4. We further assessed the contributions of various H3 interacting residues in the PHD1 domain to the binding of H3 peptides. The structural details of the H3 binding site could provide useful information to aid the development of allosteric small molecule modulators of KDM5A.


Assuntos
Cromatina , Histonas , Histonas/metabolismo , Metilação , Peptídeos/química , Domínios Proteicos , Ligação Proteica
16.
J Mol Biol ; 435(2): 167913, 2023 01 30.
Artigo em Inglês | MEDLINE | ID: mdl-36495919

RESUMO

The H3K4me3 chromatin modification, a hallmark of promoters of actively transcribed genes, is dynamically removed by the KDM5 family of histone demethylases. The KDM5 demethylases have a number of accessory domains, two of which, ARID and PHD1, lie between the segments of the catalytic domain. KDM5C, which has a unique role in neural development, harbors a number of mutations adjacent to its accessory domains that cause X-linked intellectual disability (XLID). The roles of these accessory domains remain unknown, limiting an understanding of how XLID mutations affect KDM5C activity. Through in vitro binding and kinetic studies using nucleosomes, we find that while the ARID domain is required for efficient nucleosome demethylation, the PHD1 domain alone has an inhibitory role in KDM5C catalysis. In addition, the unstructured linker region between the ARID and PHD1 domains interacts with PHD1 and is necessary for nucleosome binding. Our data suggests a model in which the PHD1 domain inhibits DNA recognition by KDM5C. This inhibitory effect is relieved by the H3 tail, enabling recognition of flanking DNA on the nucleosome. Importantly, we find that XLID mutations adjacent to the ARID and PHD1 domains break this regulation by enhancing DNA binding, resulting in the loss of specificity of substrate chromatin recognition and rendering demethylase activity lower in the presence of flanking DNA. Our findings suggest a model by which specific XLID mutations could alter chromatin recognition and enable euchromatin-specific dysregulation of demethylation by KDM5C.


Assuntos
Cromatina , Histona Desmetilases , Deficiência Intelectual Ligada ao Cromossomo X , Humanos , Cromatina/genética , Cromatina/metabolismo , DNA/química , DNA/metabolismo , Histona Desmetilases/química , Histona Desmetilases/genética , Histona Desmetilases/metabolismo , Cinética , Deficiência Intelectual Ligada ao Cromossomo X/genética , Mutação , Nucleossomos/genética , Nucleossomos/metabolismo , Ligação Proteica , Domínios Proteicos
17.
Ir J Med Sci ; 192(6): 3051-3062, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37081289

RESUMO

BACKGROUND/AIMS: Data are limited on the frequency of 'consensus decisions' between sub-specialists attending a neurovascular multidisciplinary meeting (MDM) regarding management of patients with extracranial carotid/vertebral stenoses and post-MDM 'adherence' to such advice. METHODS: This prospective audit/quality improvement project collated prospectively-recorded data from a weekly Neurovascular/Stroke Centre MDM documenting the proportion of extracranial carotid/vertebral stenosis patients in whom 'consensus management decisions' were reached by neurologists, vascular surgeons, stroke physicians-geriatricians and neuroradiologists. Adherence to MDM advice was analysed in asymptomatic carotid stenosis (ACS), symptomatic carotid stenosis (SCS), 'indeterminate symptomatic status stenosis' (ISS) and vertebral artery stenosis (VAS) patients, including intervals between index event to MDM + / - intervention. RESULTS: One hundred fifteen patients were discussed: 108 with carotid stenosis and 7 with VAS. Consensus regarding management was noted in 96.5% (111/115): 100% with ACS and VAS, 96.2% with SCS and 92.9% with ISS. Adherence to MDM management advice was 96.4% (107/111): 100% in ACS, ISS and VAS patients; 92% (46/50) in SCS patients. The median interval from index symptoms to revascularisation in 50-99% SCS patients was 12.5 days (IQR: 9-18.3 days; N = 26), with a median interval from MDM to revascularisation of 5.5 days (IQR: 1-7 days). Thirty patients underwent revascularisation. Two out of twenty-nine patients (6.9%) with either SCS or ISS had a peri-procedural ipsilateral ischaemic stroke, with no further strokes/deaths during 3-months follow-up. CONCLUSIONS: The high frequency of inter-specialty consensus regarding management and adherence to proposed treatment supports a collaborative/multidisciplinary model of care in patients with extracranial arterial stenoses. Service development should aim to shorten times between MDM discussion-intervention and optimise prevention of stroke/death.


Assuntos
Isquemia Encefálica , Estenose das Carótidas , Endarterectomia das Carótidas , Acidente Vascular Cerebral , Humanos , Estenose das Carótidas/cirurgia , Acidente Vascular Cerebral/prevenção & controle , Constrição Patológica/etiologia , Consenso , Resultado do Tratamento , Fatores de Risco
18.
Cochrane Database Syst Rev ; 10: CD007825, 2012 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-23076937

RESUMO

BACKGROUND: In many countries, national, regional and local inter- and intra-agency collaborations have been introduced to improve health outcomes. Evidence is needed on the effectiveness of locally developed partnerships which target changes in health outcomes and behaviours. OBJECTIVES: To evaluate the effects of interagency collaboration between local health and local government agencies on health outcomes in any population or age group. SEARCH METHODS: We searched the Cochrane Public Health Group Specialised Register, AMED, ASSIA, CENTRAL, CINAHL, DoPHER, EMBASE, ERIC, HMIC, IBSS, MEDLINE, MEDLINE In-Process, OpenGrey, PsycINFO, Rehabdata, Social Care Online, Social Services Abstracts, Sociological Abstracts, TRoPHI and Web of Science from 1966 through to January 2012. 'Snowballing' methods were used, including expert contact, citation tracking, website searching and reference list follow-up. SELECTION CRITERIA: Randomized controlled trials (RCTs), controlled clinical trials (CCTs), controlled before-and-after studies (CBAs) and interrupted time series (ITS) where the study reported individual health outcomes arising from interagency collaboration between health and local government agencies compared to standard care. Studies were selected independently in duplicate, with no restriction on population subgroup or disease. DATA COLLECTION AND ANALYSIS: Two authors independently conducted data extraction and assessed risk of bias for each study. MAIN RESULTS: Sixteen studies were identified (28,212 participants). Only two were considered to be at low risk of bias. Eleven studies contributed data to the meta-analyses but a narrative synthesis was undertaken for all 16 studies. Six studies examined mental health initiatives, of which one showed health benefit, four showed modest improvement in one or more of the outcomes measured but no clear overall health gain, and one showed no evidence of health gain. Four studies considered lifestyle improvements, of which one showed some limited short-term improvements, two failed to show health gains for the intervention population, and one showed more unhealthy lifestyle behaviours persisting in the intervention population. Three studies considered chronic disease management and all failed to demonstrate health gains. Three studies considered environmental improvements and adjustments, of which two showed some health improvements and one did not.Meta-analysis of three studies exploring the effect of collaboration on mortality showed no effect (pooled relative risk of 1.04 in favour of control, 95% CI 0.92 to 1.17). Analysis of five studies (with high heterogeneity) looking at the effect of collaboration on mental health resulted in a standardised mean difference of -0.28, a small effect favouring the intervention (95% CI -0.51 to -0.06). From two studies, there was a statistically significant but clinically modest improvement in the global assessment of function symptoms score scale, with a pooled mean difference (on a scale of 1 to 100) of -2.63 favouring the intervention (95% CI -5.16 to -0.10).For physical health (6 studies) and quality of life (4 studies) the results were not statistically significant, the standardised mean differences were -0.01 (95% CI -0.10 to 0.07) and -0.08 (95% CI -0.44 to 0.27), respectively. AUTHORS' CONCLUSIONS: Collaboration between local health and local government is commonly considered best practice. However, the review did not identify any reliable evidence that interagency collaboration, compared to standard services, necessarily leads to health improvement. A few studies identified component benefits but these were not reflected in overall outcome scores and could have resulted from the use of significant additional resources. Although agencies appear enthusiastic about collaboration, difficulties in the primary studies and incomplete implementation of initiatives have prevented the development of a strong evidence base. If these weaknesses are addressed in future studies (for example by providing greater detail on the implementation of programmes; using more robust designs, integrated process evaluations to show how well the partners of the collaboration worked together, and measurement of health outcomes) it could provide a better understanding of what might work and why. It is possible that local collaborative partnerships delivering environmental Interventions may result in health gain but the evidence base for this is very limited.Evaluations of interagency collaborative arrangements face many challenges. The results demonstrate that collaborative community partnerships can be established to deliver interventions but it is important to agree goals, methods of working, monitoring and evaluation before implementation to protect programme fidelity and increase the potential for effectiveness.


Assuntos
Órgãos Governamentais/organização & administração , Promoção da Saúde/organização & administração , Órgãos dos Sistemas de Saúde/organização & administração , Relações Interinstitucionais , Governo Local , Humanos , Mortalidade , Ensaios Clínicos Controlados Aleatórios como Assunto
19.
Cell Rep Med ; 3(7): 100696, 2022 07 19.
Artigo em Inglês | MEDLINE | ID: mdl-35858588

RESUMO

The cholinergic anti-inflammatory pathway is the efferent arm of the inflammatory reflex, a neural circuit through which the CNS can modulate peripheral immune responses. Signals communicated via the vagus and splenic nerves use acetylcholine, produced by Choline acetyltransferase (ChAT)+ T cells, to downregulate the inflammatory actions of macrophages expressing α7 nicotinic receptors. Pre-clinical studies using transgenic animals, cholinergic agonists, vagotomy, and vagus nerve stimulation have demonstrated this pathway's role and therapeutic potential in numerous inflammatory diseases. In this review, we summarize what is understood about the inflammatory reflex. We also demonstrate how pre-clinical findings are being translated into promising clinical trials, and we draw particular attention to innovative bioelectronic methods of harnessing the cholinergic anti-inflammatory pathway for clinical use.


Assuntos
Neuroimunomodulação , Estimulação do Nervo Vago , Animais , Neuroimunomodulação/fisiologia , Reflexo/fisiologia , Nervo Vago , Receptor Nicotínico de Acetilcolina alfa7/metabolismo
20.
ACS Chem Biol ; 17(10): 2710-2715, 2022 10 21.
Artigo em Inglês | MEDLINE | ID: mdl-36166818

RESUMO

While there has been recent success in the development of KRasG12C inhibitors, unmet needs for selective inhibitors of KRasG12D and the remaining oncogenic KRas proteins remain. Here, we applied trifluoromethyl-containing ligands of KRas proteins as competitive probe ligands to assay the occupancy of the switch II pocket by 19F NMR spectroscopy. Structure-activity-relationship studies of probe ligands increased the sensitivity of the assay and identified structures that differentially detected each nucleotide state of KRasG12D. These differences in selectivity, combined with the high resolution of 19F NMR spectroscopy, enabled this method to be expanded to assay both nucleotide states of the protein simultaneously.


Assuntos
Flúor , Genes ras , Ligantes , Espectroscopia de Ressonância Magnética , Nucleotídeos , Proteínas Proto-Oncogênicas p21(ras)/genética , Mutação
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