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1.
Mol Cell ; 71(1): 89-102.e5, 2018 07 05.
Artigo em Inglês | MEDLINE | ID: mdl-29979971

RESUMO

Accessible chromatin is important for RNA polymerase II recruitment and transcription initiation at eukaryotic promoters. We investigated the mechanistic links between promoter DNA sequence, nucleosome positioning, and transcription. Our results indicate that positioning of the transcription start site-associated +1 nucleosome in yeast is critical for efficient TBP binding and is driven by two key factors, the essential chromatin remodeler RSC and a small set of ubiquitous general regulatory factors (GRFs). Our findings indicate that the strength and directionality of RSC action on promoter nucleosomes depends on the arrangement and proximity of two specific DNA motifs. This, together with the effect on nucleosome position observed in double depletion experiments, suggests that, despite their widespread co-localization, RSC and GRFs predominantly act through independent signals to generate accessible chromatin. Our results provide mechanistic insight into how the promoter DNA sequence instructs trans-acting factors to control nucleosome architecture and stimulate transcription initiation.


Assuntos
Montagem e Desmontagem da Cromatina , Nucleossomos/metabolismo , RNA Polimerase II/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/metabolismo , Transcrição Gênica , Nucleossomos/genética , RNA Polimerase II/genética , Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/genética
2.
Genes Dev ; 32(17-18): 1252-1265, 2018 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-30108132

RESUMO

The transcriptional coactivators Mediator and two histone acetyltransferase (HAT) complexes, NuA4 and SAGA, play global roles in transcriptional activation. Here we explore the relative contributions of these factors to RNA polymerase II association at specific genes and gene classes by rapid nuclear depletion of key complex subunits. We show that the NuA4 HAT Esa1 differentially affects certain groups of genes, whereas the SAGA HAT Gcn5 has a weaker but more uniform effect. Relative dependence on Esa1 and Tra1, a shared component of NuA4 and SAGA, distinguishes two large groups of coregulated growth-promoting genes. In contrast, we show that the activity of Mediator is particularly important at a separate, small set of highly transcribed TATA-box-containing genes. Our analysis indicates that at least three distinct combinations of coactivator deployment are used to generate moderate or high transcription levels and suggests that each may be associated with distinct forms of regulation.


Assuntos
Regulação Fúngica da Expressão Gênica , Histona Acetiltransferases/fisiologia , Complexo Mediador/fisiologia , Proteínas de Saccharomyces cerevisiae/fisiologia , Saccharomyces cerevisiae/genética , Ativação Transcricional , Acetilação , Histonas/metabolismo , Complexo Mediador/metabolismo , Estresse Oxidativo/genética , Regiões Promotoras Genéticas , Saccharomyces cerevisiae/enzimologia , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Proteína de Ligação a TATA-Box/metabolismo , Transcrição Gênica
3.
Mol Cell ; 65(3): 578-580, 2017 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-28157510

RESUMO

In this issue of Molecular Cell, Chereji et al. (2017) present new data on MNase-sensitive particles previously identified upstream of transcription start sites at many promoters in budding yeast, and they argue, based upon negative histone-ChIP results, that they are non-nucleosomal signals generated by transcription factors (TFs). We show instead, based upon functional experiments where the relevant TFs are rapidly depleted, that this explanation does not hold, and we argue instead that histone ChIP and chemical cleavage assays have a limited capacity to capture these highly dynamic, MNase-sensitive "fragile" nucleosomes.


Assuntos
Histonas/genética , Nucleossomos , Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/genética , Sítio de Iniciação de Transcrição
4.
Eur J Neurol ; 31(6): e16266, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38469975

RESUMO

BACKGROUND AND PURPOSE: Thalamic alterations have been reported as a major feature in presymptomatic and symptomatic patients carrying the C9orf72 mutation across the frontotemporal dementia-amyotrophic lateral sclerosis (ALS) spectrum. Specifically, the pulvinar, a high-order thalamic nucleus and timekeeper for large-scale cortical networks, has been hypothesized to be involved in C9orf72-related neurodegenerative diseases. We investigated whether pulvinar volume can be useful for differential diagnosis in ALS C9orf72 mutation carriers and noncarriers and how underlying functional connectivity changes affect this region. METHODS: We studied 19 ALS C9orf72 mutation carriers (ALSC9+) accurately matched with wild-type ALS (ALSC9-) and ALS mimic (ALSmimic) patients using structural and resting-state functional magnetic resonance imaging data. Pulvinar volume was computed using automatic segmentation. Seed-to-voxel functional connectivity analyses were performed using seeds from a pulvinar functional parcellation. RESULTS: Pulvinar structural integrity had high discriminative values for ALSC9+ patients compared to ALSmimic (area under the curve [AUC] = 0.86) and ALSC9- (AUC = 0.77) patients, yielding a volume cutpoint of approximately 0.23%. Compared to ALSmimic, ALSC9- showed increased anterior, inferior, and lateral pulvinar connections with bilateral occipital-temporal-parietal regions, whereas ALSC9+ showed no differences. ALSC9+ patients when compared to ALSC9- patients showed reduced pulvinar-occipital connectivity for anterior and inferior pulvinar seeds. CONCLUSIONS: Pulvinar volume could be a differential biomarker closely related to the C9orf72 mutation. A pulvinar-cortical circuit dysfunction might play a critical role in disease progression and development, in both the genetic phenotype and ALS wild-type patients.


Assuntos
Esclerose Lateral Amiotrófica , Proteína C9orf72 , Imageamento por Ressonância Magnética , Mutação , Pulvinar , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Esclerose Lateral Amiotrófica/genética , Esclerose Lateral Amiotrófica/diagnóstico por imagem , Esclerose Lateral Amiotrófica/fisiopatologia , Esclerose Lateral Amiotrófica/patologia , Proteína C9orf72/genética , Demência Frontotemporal/genética , Demência Frontotemporal/fisiopatologia , Demência Frontotemporal/diagnóstico por imagem , Demência Frontotemporal/patologia , Heterozigoto , Pulvinar/diagnóstico por imagem , Pulvinar/fisiopatologia , Pulvinar/patologia
5.
Semin Neurol ; 44(2): 130-146, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38537703

RESUMO

The burden of epilepsy in the Latin America and the Caribbean (LAC) region causes a profound regional impact on the health care system and significantly contributes to the global epilepsy burden. As in many other resource-limited settings worldwide, health care professionals and patients with epilepsy in LAC countries face profound challenges due to a combination of factors, including high disease prevalence, stigmatization of epilepsy, disparities in access to care, limited resources, substantial treatment gaps, insufficient training opportunities for health care providers, and a diverse patient population with varying needs. This article presents an overview of the epidemiology of epilepsy and discusses the principal obstacles to epilepsy care and key contributors to the epilepsy diagnosis and treatment gap in the LAC region. We conclude by highlighting various initiatives across different LAC countries to improve epilepsy care in marginalized communities, listing strategies to mitigate treatment gaps and facilitate better health care access for patients with epilepsy by enhancing the epilepsy workforce.


Assuntos
Epilepsia , Acessibilidade aos Serviços de Saúde , Humanos , Região do Caribe/epidemiologia , América Latina/epidemiologia , Prevalência
6.
Anesth Analg ; 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-39088366

RESUMO

Postoperative delirium (POD) is frequent in older adults and is associated with adverse cognitive and functional outcomes. In the last several decades, there has been an increased interest in exploring tools that easily allow the early recognition of patients at risk of developing POD. The electroencephalogram (EEG) is a widely available tool used to understand delirium pathophysiology, and its use in the perioperative setting has grown exponentially, particularly to predict and detect POD. We performed a systematic review to investigate the use of EEG in the pre-, intra-, and postoperative settings. We identified 371 studies, and 56 met the inclusion criteria. A range of techniques was used to obtain EEG data, from limited 1-4 channel setups to complex 256-channel systems. Power spectra were often measured preoperatively, yet the outcomes were inconsistent. During surgery, the emphasis was primarily on burst suppression (BS) metrics and power spectra, with a link between the frequency and timing of BS, and POD. The EEG patterns observed in POD aligned with those noted in delirium in different contexts, suggesting a reduction in EEG activity. Further research is required to investigate preoperative EEG indicators that may predict susceptibility to delirium.

7.
Mol Cell ; 64(4): 720-733, 2016 11 17.
Artigo em Inglês | MEDLINE | ID: mdl-27818142

RESUMO

Cell growth potential is determined by the rate of ribosome biogenesis, a complex process that requires massive and coordinated transcriptional output. In the yeast Saccharomyces cerevisiae, ribosome biogenesis is highly regulated at the transcriptional level. Although evidence for a system that coordinates ribosomal RNA (rRNA) and ribosomal protein gene (RPG) transcription has been described, the molecular mechanisms remain poorly understood. Here we show that an interaction between the RPG transcriptional activator Ifh1 and the rRNA processing factor Utp22 serves to coordinate RPG transcription with that of rRNA. We demonstrate that Ifh1 is rapidly released from RPG promoters by a Utp22-independent mechanism following growth inhibition, but that its long-term dissociation requires Utp22. We present evidence that RNA polymerase I activity inhibits the ability of Utp22 to titrate Ifh1 from RPG promoters and propose that a dynamic Ifh1-Utp22 interaction fine-tunes RPG expression to coordinate RPG and rRNA transcription.


Assuntos
Regulação Fúngica da Expressão Gênica , RNA Ribossômico/genética , Proteínas Ribossômicas/genética , Proteínas de Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/genética , Transativadores/genética , Biogênese de Organelas , Regiões Promotoras Genéticas , Ligação Proteica , RNA Polimerase I/genética , RNA Polimerase I/metabolismo , RNA Ribossômico/biossíntese , Proteínas Ribossômicas/biossíntese , Proteínas Ribossômicas/metabolismo , Ribossomos/genética , Ribossomos/metabolismo , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Transativadores/metabolismo , Transcrição Gênica
8.
Artigo em Espanhol | MEDLINE | ID: mdl-38352034

RESUMO

Objective: Conduct an analysis to determine the existence and updating of national essential medicines lists (EMLs) and clinical practice guidelines (CPGs) for the treatment of diabetes in Latin America and the Caribbean (LAC); and compare the medicines included in each country's list and guidelines both with each other and with those of the World Health Organization (WHO). Methods: Cross-sectional study. EMLs and CPGs for diabetes were found on the websites of the Pan American Health Organization and national health authorities. Medicines were noted and analyzed according to pharmacological group, based on the fourth level of nomenclature of the Anatomical Therapeutic Chemical (ATC) classification system. F1 scoring was used to assess the proximity of EMLs to the WHO Model List of Essential Medicines (MLEM). Results: Of the total number of countries, 87.2% have EMLs, and 91% have CPGs (78% and 45% updated in the last five years, respectively). Compared to the six hypoglycemic groups of the MLEM, the EMLs had a median (range) of 6 (4-13) and an F1 score of 0.80; This indicates proper alignment. CPGs had a median (range) of 12 (1-12) hypoglycemic drugs compared to eight in the WHO guidelines. CPGs had a median of 15 more drugs than their respective EMLs. Conclusions: While most LAC countries have EMLs and CPGs for diabetes, the lack of concordance among them limits their effectiveness. It is necessary to align the processes and criteria for the development of these two tools for policymaking on medicines.


Objetivos: Analisar a existência e a atualização das listas nacionais de medicamentos (LNMs) e guias de prática clínica (GPCs) para o tratamento do diabetes na América Latina e no Caribe (ALC). Comparar os medicamentos incluídos nas listas e nas diretrizes de cada país entre si e com as da Organização Mundial da Saúde (OMS). Métodos: Estudo transversal. Foram identificadas LMNs e GPCs para o diabetes nos sites da Organização Pan-Americana da Saúde e das autoridades sanitárias nacionais. Os medicamentos foram pesquisados e analisados por grupo farmacológico de acordo com o quarto nível da classificação ATC. A pontuação F1 foi utilizada para avaliar o grau de proximidade das LMNs com a lista-modelo de medicamentos essenciais (LMME) da OMS. Resultados: Do total de países, 87,2% dispõem de uma LNM e 91%, de GPCs (78% e 45%, respectivamente, atualizadas nos últimos 5 anos). Em comparação com os seis grupos de agentes hipoglicemiantes da LMME, as LMNs tinham uma mediana (intervalo) de 6 (4 a 13) e uma pontuação F1 de 0,80, o que indica uma conformidade adequada. As GPCs tinham uma mediana (intervalo) de 12 (1 a 12) agentes hipoglicemiantes, em comparação com 8 nos guias da OMS. As GPCs tinham uma mediana de 15 medicamentos a mais do que as respectivas LNMs. Conclusões: Embora a maioria dos países da América Latina e do Caribe disponha de LNMs e GPCs para o diabetes, a falta de concordância entre elas limita sua eficácia. É necessário alinhar os processos e os critérios de desenvolvimento dessas duas ferramentas da política de medicamentos.

9.
J Headache Pain ; 25(1): 97, 2024 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-38858629

RESUMO

BACKGROUND: Mindfulness practice has gained interest in the management of Chronic Migraine associated with Medication Overuse Headache (CM-MOH). Mindfulness is characterized by present-moment self-awareness and relies on attention control and emotion regulation, improving headache-related pain management. Mindfulness modulates the Default Mode Network (DMN), Salience Network (SN), and Fronto-Parietal Network (FPN) functional connectivity. However, the neural mechanisms underlying headache-related pain management with mindfulness are still unclear. In this study, we tested neurofunctional changes after mindfulness practice added to pharmacological treatment as usual in CM-MOH patients. METHODS: The present study is a longitudinal phase-III single-blind Randomized Controlled Trial (MIND-CM study; NCT03671681). Patients had a diagnosis of CM-MOH, no history of neurological and severe psychiatric comorbidities, and were attending our specialty headache centre. Patients were divided in Treatment as Usual (TaU) and mindfulness added to TaU (TaU + MIND) groups. Patients underwent a neuroimaging and clinical assessment before the treatment and after one year. Longitudinal comparisons of DMN, SN, and FPN connectivity were performed between groups and correlated with clinical changes. Vertex-wise analysis was performed to assess cortical thickness changes. RESULTS: 177 CM-MOH patients were randomized to either TaU group or TaU + MIND group. Thirty-four patients, divided in 17 TaU and 17 TaU + MIND, completed the neuroimaging follow-up. At the follow-up, both groups showed an improvement in most clinical variables, whereas only TaU + MIND patients showed a significant headache frequency reduction (p = 0.028). After one year, TaU + MIND patients showed greater SN functional connectivity with the left posterior insula (p-FWE = 0.007) and sensorimotor cortex (p-FWE = 0.026). In TaU + MIND patients only, greater SN-insular connectivity was associated with improved depression scores (r = -0.51, p = 0.038). A longitudinal increase in cortical thickness was observed in the insular cluster in these patients (p = 0.015). Increased anterior cingulate cortex thickness was also reported in TaU + MIND group (p-FWE = 0.02). CONCLUSIONS: Increased SN-insular connectivity might modulate chronic pain perception and the management of negative emotions. Enhanced SN-sensorimotor connectivity could reflect improved body-awareness of painful sensations. Expanded cingulate cortex thickness might sustain improved cognitive processing of nociceptive information. Our findings unveil the therapeutic potential of mindfulness and the underlying neural mechanisms in CM-MOH patients. TRIAL REGISTRATION: Name of Registry; MIND-CM study; Registration Number ClinicalTrials.gov identifier: NCT0367168; Registration Date: 14/09/2018.


Assuntos
Transtornos da Cefaleia Secundários , Atenção Plena , Humanos , Atenção Plena/métodos , Transtornos da Cefaleia Secundários/terapia , Transtornos da Cefaleia Secundários/psicologia , Feminino , Masculino , Adulto , Pessoa de Meia-Idade , Estudos Longitudinais , Método Simples-Cego , Imageamento por Ressonância Magnética , Rede de Modo Padrão/diagnóstico por imagem , Rede de Modo Padrão/fisiopatologia , Córtex Cerebral/diagnóstico por imagem , Córtex Cerebral/fisiopatologia
10.
J Headache Pain ; 25(1): 7, 2024 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-38212704

RESUMO

BACKGROUND: Despite hypothalamus has long being considered to be involved in the pathophysiology of cluster headache, the inconsistencies of previous neuroimaging studies and a limited understanding of the hypothalamic areas involved, impede a comprehensive interpretation of its involvement in this condition. METHODS: We used an automated algorithm to extract hypothalamic subunit volumes from 105 cluster headache patients (57 chronic and 48 episodic) and 59 healthy individuals; after correcting the measures for the respective intracranial volumes, we performed the relevant comparisons employing logist regression models. Only for subunits that emerged as abnormal, we calculated their correlation with the years of illness and the number of headache attacks per day, and the effects of lithium treatment. As a post-hoc approach, using the 7 T resting-state fMRI dataset from the Human Connectome Project, we investigated whether the observed abnormal subunit, comprising the paraventricular nucleus and preoptic area, shows robust functional connectivity with the mesocorticolimbic system, which is known to be modulated by oxytocin neurons in the paraventricular nucleus and that is is abnormal in chronic cluster headache patients. RESULTS: Patients with chronic (but not episodic) cluster headache, compared to control participants, present an increased volume of the anterior-superior hypothalamic subunit ipsilateral to the pain, which, remarkably, also correlates significantly with the number of daily attacks. The post-hoc approach showed that this hypothalamic area presents robust functional connectivity with the mesocorticolimbic system under physiological conditions. No evidence of the effects of lithium treatment on this abnormal subunit was found. CONCLUSIONS: We identified the ipsilateral-to-the-pain antero-superior subunit, where the paraventricular nucleus and preoptic area are located, as the key hypothalamic region of the pathophysiology of chronic cluster headache. The significant correlation between the volume of this area and the number of daily attacks crucially reinforces this interpretation. The well-known roles of the paraventricular nucleus in coordinating autonomic and neuroendocrine flow in stress adaptation and modulation of trigeminovascular mechanisms offer important insights into the understanding of the pathophysiology of cluster headache.


Assuntos
Cefaleia Histamínica , Humanos , Cefaleia Histamínica/terapia , Dor , Cefaleia , Hipotálamo/diagnóstico por imagem , Compostos de Lítio
11.
Neuroimage ; 270: 119961, 2023 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-36848970

RESUMO

Intracranial electroencephalography (iEEG) presents a unique opportunity to extend human neuroscientific understanding. However, typically iEEG is collected from patients diagnosed with focal drug-resistant epilepsy (DRE) and contains transient bursts of pathological activity. This activity disrupts performances on cognitive tasks and can distort findings from human neurophysiology studies. In addition to manual marking by a trained expert, numerous IED detectors have been developed to identify these pathological events. Even so, the versatility and usefulness of these detectors is limited by training on small datasets, incomplete performance metrics, and lack of generalizability to iEEG. Here, we employed a large annotated public iEEG dataset from two institutions to train a random forest classifier (RFC) to distinguish data segments as either 'non-cerebral artifact' (n = 73,902), 'pathological activity' (n = 67,797), or 'physiological activity' (n = 151,290). We found our model performed with an accuracy of 0.941, specificity of 0.950, sensitivity of 0.908, precision of 0.911, and F1 score of 0.910, averaged across all three event types. We extended the generalizability of our model to continuous bipolar data collected in a task-state at a different institution with a lower sampling rate and found our model performed with an accuracy of 0.789, specificity of 0.806, and sensitivity of 0.742, averaged across all three event types. Additionally, we created a custom graphical user interface to implement our classifier and enhance usability.


Assuntos
Artefatos , Eletroencefalografia , Humanos , Eletrocorticografia , Neurofisiologia , Cognição
12.
Semin Neurol ; 43(5): 675-688, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37832589

RESUMO

Electroencephalography (EEG) is a noninvasive tool that allows the monitoring of cerebral brain function in critically ill patients, aiding with diagnosis, management, and prognostication. Specific EEG features have shown utility in the prediction of outcomes in critically ill patients with status epilepticus, acute brain injury (ischemic stroke, intracranial hemorrhage, subarachnoid hemorrhage, and traumatic brain injury), anoxic brain injury, and toxic-metabolic encephalopathy. Studies have also found an association between particular EEG patterns and long-term functional and cognitive outcomes as well as prediction of recovery of consciousness following acute brain injury. This review summarizes these findings and demonstrates the value of utilizing EEG findings in the determination of prognosis.


Assuntos
Lesões Encefálicas , Estado Terminal , Humanos , Eletroencefalografia , Lesões Encefálicas/diagnóstico , Prognóstico , Biomarcadores
13.
Epilepsy Behav ; 144: 109279, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37271018

RESUMO

BACKGROUND: The ketogenic diet (KD) is a high-fat, low-carbohydrate diet with therapeutic potential in refractory seizures, both in outpatient and inpatient settings. Successful implementation of KD involves a multifaceted, interdisciplinary approach to address anticipated challenges. We sought to characterize the utilization of KD among healthcare providers caring for adults with status epilepticus (SE). METHODS: We distributed a web-based survey through professional societies, including the American Academy of Neurology (AAN), Neurocritical Care Society (NCS), American Epilepsy Society (AES), Neuro Anesthesia and Critical Care Society (NACCS), and the Academy of Nutrition and Dietetics (AND), and via research contacts. We asked respondents about practice experience and experience using KD as a treatment for SE. Descriptive statistics and Chi-square tests were used to analyze the results. RESULTS: Of 156 respondents, 80% of physicians and 18% of non-physicians reported experience with KD for SE. Anticipated difficulty in achieving ketosis (36.3%), lack of expertise (24.2%), and lack of resources (20.9%) were identified as the most important barriers limiting the utilization of KD. The absence of dietitians (37.1%) or pharmacists (25.7%) support was the most important missing resource. Reasons for stopping KD included perceived ineffectiveness (29.1%), difficulty achieving ketosis (24.6%), and side effects (17.3%). Academic centers had more experience with the use of KD and greater EEG monitoring availability and fewer barriers to its implementation. The need for randomized clinical trials supporting efficacy (36.5%) and better practice guidelines for implementation and maintenance of KD (29.6%) were cited most frequently as factors to increase utilization of KD. CONCLUSION: This study identifies important barriers to the utilization of KD as a treatment for SE despite evidence supporting its efficacy in the appropriate clinical context, namely lack of resources and interdisciplinary support, and lack of established practice guidelines. Our results highlight the need for future research to improve understanding of the efficacy and safety of KD along with better interdisciplinary collaborations to increase its utilization.


Assuntos
Dieta Cetogênica , Epilepsia , Cetose , Estado Epiléptico , Humanos , Adulto , Dieta Cetogênica/métodos , Estado Epiléptico/tratamento farmacológico , Dieta com Restrição de Carboidratos/métodos , Resultado do Tratamento
14.
Mol Cell ; 60(3): 422-34, 2015 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-26545077

RESUMO

Previous studies indicate that eukaryotic promoters display a stereotypical chromatin landscape characterized by a well-positioned +1 nucleosome near the transcription start site and an upstream -1 nucleosome that together demarcate a nucleosome-free (or -depleted) region. Here we present evidence that there are two distinct types of promoters distinguished by the resistance of the -1 nucleosome to micrococcal nuclease digestion. These different architectures are characterized by two sequence motifs that are broadly deployed at one set of promoters where a nuclease-sensitive ("fragile") nucleosome forms, but concentrated in a narrower, nucleosome-free region at all other promoters. The RSC nucleosome remodeler acts through the motifs to establish stable +1 and -1 nucleosome positions, while binding of a small set of general regulatory (pioneer) factors at fragile nucleosome promoters plays a key role in their destabilization. We propose that the fragile nucleosome promoter architecture is adapted for regulation of highly expressed, growth-related genes.


Assuntos
Regulação Fúngica da Expressão Gênica/fisiologia , Nucleossomos/metabolismo , Regiões Promotoras Genéticas/fisiologia , Proteínas de Saccharomyces cerevisiae/biossíntese , Saccharomyces cerevisiae/metabolismo , Nucleossomos/genética , Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/genética
15.
Neurocrit Care ; 38(1): 41-51, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36071331

RESUMO

BACKGROUND: The objective of this study was to determine the prevalence of pyridoxine deficiency, measured by pyridoxal phosphate (PLP) levels, in patients admitted to the hospital with established (benzodiazepine-resistant) status epilepticus (SE) (eSE) and to compare to three control groups: intensive care unit (ICU) patients without SE (ICU-noSE), non-ICU inpatients without SE (non-ICU), and outpatients with or without a history of epilepsy (outpatient). METHODS: This retrospective cohort study was conducted at the University of North Carolina Hospitals and Yale New Haven Hospital. Participants included inpatients and outpatients who had serum PLP levels measured during clinical care between January 2018 and March 2021. The first PLP level obtained was categorized as normal (> 30 nmol/L), marginal (≤ 30 nmol/L), deficient (≤ 20 nmol/L), and severely deficient (≤ 5 nmol/L). RESULTS: A total of 293 patients were included (52 eSE, 40 ICU-noSE, 44 non-ICU, and 157 outpatient). The median age was 55 (range 19-99) years. The median PLP level of the eSE group (12 nmol/L) was lower than that of the ICU-noSE (22 nmol/L, p = 0.003), non-ICU (16 nmol/L, p = 0.05), and outpatient groups (36 nmol/L, p < 0.001). Patients with eSE had a significantly higher prevalence of marginal and deficient PLP levels (90 and 80%, respectively) than patients in each of the other three groups (ICU-noSE: 70, 50%; non-ICU: 63, 54%; outpatient: 38, 21%). This significantly higher prevalence persisted after correcting for critical illness severity and timing of PLP level collection. CONCLUSIONS: Our study confirms previous findings indicating a high prevalence of pyridoxine deficiency (as measured by serum PLP levels) in patients with eSE, including when using a more restricted definition of pyridoxine deficiency. Prevalence is higher in patients with eSE than in patients in all three control groups (ICU-noSE, non-ICU, and outpatient). Considering the role of pyridoxine, thus PLP, in the synthesis of γ-aminobutyric acid and its easy and safe administration, prospective studies on pyridoxine supplementation in patients with eSE are needed.


Assuntos
Estado Epiléptico , Deficiência de Vitamina B 6 , Humanos , Adulto Jovem , Adulto , Pessoa de Meia-Idade , Idoso , Idoso de 80 Anos ou mais , Piridoxal , Piridoxina , Fosfato de Piridoxal , Deficiência de Vitamina B 6/epidemiologia , Estudos Prospectivos , Estudos Retrospectivos , Estado Epiléptico/tratamento farmacológico , Estado Epiléptico/epidemiologia
16.
Hum Brain Mapp ; 43(3): 998-1010, 2022 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-34734458

RESUMO

Neurobiological pain models propose that chronic pain is accompanied by neurofunctional changes that mediate pain processing dysfunctions. In contrast, meta-analyses of neuroimaging studies in chronic pain conditions have not revealed convergent evidence for robust alterations during experimental pain induction. Against this background, the present neuroimaging meta-analysis combined three different meta-analytic approaches with stringent study selection criteria for case-control functional magnetic resonance imaging experiments during acute pain processing with a focus on chronic pain disorders. Convergent neurofunctional dysregulations in chronic pain patients were observed in the left anterior insula cortex. Seed-based resting-state functional connectivity based on a large publicly available dataset combined with a meta-analytic task-based approach identified the anterior insular region as a key node of an extended bilateral insula-fronto-cingular network, resembling the salience network. Moreover, the meta-analytic decoding showed that this region presents a high probability to be specifically activated during pain-related processes, although we cannot exclude an involvement in autonomic processes. Together, the present findings indicate that dysregulated left anterior insular activity represents a robust neurofunctional maladaptation and potential treatment target in chronic pain disorders.


Assuntos
Dor Crônica/diagnóstico por imagem , Dor Crônica/fisiopatologia , Neuroimagem Funcional , Córtex Insular/diagnóstico por imagem , Córtex Insular/fisiopatologia , Humanos
17.
Genet Med ; 24(1): 29-40, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34906452

RESUMO

PURPOSE: This study aimed to unravel the genetic factors underlying missing heritability in spinocerebellar ataxia type 17 (SCA17) caused by polyglutamine-encoding CAG/CAA repeat expansions in the TBP gene. Alleles with >49 CAG/CAA repeats are fully penetrant. Most patients, however, carry intermediate TBP41-49 alleles that show incomplete penetrance. METHODS: Using next-generation sequencing approaches, we investigated 40 SCA17/TBP41-54 index patients, their affected (n = 55) and unaffected (n = 51) relatives, and a cohort of patients with ataxia (n = 292). RESULTS: All except 1 (30/31) of the index cases with TBP41-46 alleles carried a heterozygous pathogenic variant in the STUB1 gene associated with spinocerebellar ataxias SCAR16 (autosomal recessive) and SCA48 (autosomal dominant). No STUB1 variant was found in patients carrying TBP47-54 alleles. TBP41-46 expansions and STUB1 variants cosegregate in all affected family members, whereas the presence of either TBP41-46 expansions or STUB1 variants individually was never associated with the disease. CONCLUSION: Our data reveal an unexpected genetic interaction between STUB1 and TBP in the pathogenesis of SCA17 and raise questions on the existence of SCA48 as a monogenic disease with crucial implications for diagnosis and counseling. They provide a convincing explanation for the incomplete penetrance of intermediate TBP alleles and demonstrate a dual inheritance pattern for SCA17, which is a monogenic dominant disorder for TBP≥47 alleles and a digenic TBP/STUB1 disease (SCA17-DI) for intermediate expansions.


Assuntos
Peptídeos , Ataxias Espinocerebelares , Proteína de Ligação a TATA-Box , Ubiquitina-Proteína Ligases , Humanos , Penetrância , Peptídeos/genética , Ataxias Espinocerebelares/genética , Ataxias Espinocerebelares/patologia , Proteína de Ligação a TATA-Box/genética , Expansão das Repetições de Trinucleotídeos/genética , Ubiquitina-Proteína Ligases/genética
18.
Mov Disord ; 37(11): 2289-2295, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36036203

RESUMO

BACKGROUND: Magnetic resonance-guided focused ultrasound (MRgFUS) thalamotomy is a safe and effective procedure for drug-resistant tremor in Parkinson's disease (PD). OBJECTIVE: The aim of this study was to demonstrate that MRgFUS ventralis intermedius thalamotomy in early-stage tremor-dominant PD may prevent an increase in dopaminergic medication 6 months after treatment compared with matched PD control subjects on standard medical therapy. METHODS: We prospectively enrolled patients with early-stage PD who underwent MRgFUS ventralis intermedius thalamotomy (PD-FUS) and patients treated with oral dopaminergic therapy (PD-ODT) with a 1:2 ratio. We collected demographic and clinical data at baseline and 6 and 12 months after thalamotomy. RESULTS: We included 10 patients in the PD-FUS group and 20 patients in the PD-ODT group. We found a significant increase in total levodopa equivalent daily dose and levodopa plus monoamine oxidase B inhibitors dose in the PD-ODT group 6 months after thalamotomy. CONCLUSIONS: In early-stage tremor-dominant PD, MRgFUS thalamotomy may be useful to reduce tremor and avoid the need to increase dopaminergic medications. © 2022 The Authors. Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society.


Assuntos
Tremor Essencial , Doença de Parkinson , Humanos , Tremor/tratamento farmacológico , Tremor/etiologia , Tremor/cirurgia , Doença de Parkinson/tratamento farmacológico , Doença de Parkinson/cirurgia , Tremor Essencial/tratamento farmacológico , Tremor Essencial/cirurgia , Projetos Piloto , Levodopa/uso terapêutico , Tálamo/diagnóstico por imagem , Tálamo/cirurgia , Imageamento por Ressonância Magnética/métodos , Espectroscopia de Ressonância Magnética , Resultado do Tratamento
19.
Psychol Med ; 52(8): 1491-1500, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-32962777

RESUMO

BACKGROUND: Despite a growing understanding of disorders of consciousness following severe brain injury, the association between long-term impairment of consciousness, spontaneous brain oscillations, and underlying subcortical damage, and the ability of such information to aid patient diagnosis, remains incomplete. METHODS: Cross-sectional observational sample of 116 patients with a disorder of consciousness secondary to brain injury, collected prospectively at a tertiary center between 2011 and 2013. Multimodal analyses relating clinical measures of impairment, electroencephalographic measures of spontaneous brain activity, and magnetic resonance imaging data of subcortical atrophy were conducted in 2018. RESULTS: In the final analyzed sample of 61 patients, systematic associations were found between electroencephalographic power spectra and subcortical damage. Specifically, the ratio of beta-to-delta relative power was negatively associated with greater atrophy in regions of the bilateral thalamus and globus pallidus (both left > right) previously shown to be preferentially atrophied in chronic disorders of consciousness. Power spectrum total density was also negatively associated with widespread atrophy in regions of the left globus pallidus, right caudate, and in the brainstem. Furthermore, we showed that the combination of demographics, encephalographic, and imaging data in an analytic framework can be employed to aid behavioral diagnosis. CONCLUSIONS: These results ground, for the first time, electroencephalographic presentation detected with routine clinical techniques in the underlying brain pathology of disorders of consciousness and demonstrate how multimodal combination of clinical, electroencephalographic, and imaging data can be employed in potentially mitigating the high rates of misdiagnosis typical of this patient cohort.


Assuntos
Lesões Encefálicas , Estado de Consciência , Atrofia , Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Lesões Encefálicas/patologia , Estudos Transversais , Eletroencefalografia , Humanos , Imageamento por Ressonância Magnética/métodos
20.
Cerebellum ; 21(1): 133-144, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34106418

RESUMO

Spinocerebellar ataxias type 1 (SCA1) is an autosomal dominant disease usually manifesting in adulthood. We performed a prospective 1-year longitudinal study in 14 presymptomatic mutation carriers (preSCA1), 11 ataxic patients, and 21 healthy controls. SCA1 patients had a median disease duration of 6 years (range 2-16) and SARA score of 7 points (range 3.5-20). PreSCA1 had an estimated time before disease onset of 9.7 years (range 4-30), and no signs of ataxia. At baseline, SCA1 patients significantly differed from controls in SARA score (Scale for Assessment and Rating of Ataxia), cognitive tests, and structural MRI measures. Significant volume loss was found in cerebellum, brainstem, basal ganglia, and cortical thinning in frontal, temporal, and occipital regions. PreSCA1 did not differ from controls. At 1-year follow-up, SCA1 patients showed significant increase in SARA score, and decreased volume of cerebellum (- 0.6%), pons (- 5.5%), superior cerebellar peduncles (- 10.7%), and midbrain (- 3.0%). Signs of disease progression were also observed in preSCA1 subjects, with increased SARA score and reduced total cerebellar volume. Our exploratory study suggests that clinical scores and MRI measures provide valuable data to monitor and quantify the earliest changes associated with the preclinical and the symptomatic phases of SCA1 disease.


Assuntos
Ataxias Espinocerebelares , Adulto , Progressão da Doença , Humanos , Estudos Longitudinais , Imageamento por Ressonância Magnética , Estudos Prospectivos , Ataxias Espinocerebelares/complicações , Ataxias Espinocerebelares/diagnóstico por imagem , Ataxias Espinocerebelares/genética
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