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Targeting synthetic lethal interactions between genes has emerged as a promising strategy for cancer therapy. This study explores the intricate interplay between terminal uridyltransferase 4 (TUT4) and terminal uridyltransferase 7 (TUT7), the 3'-5' exoribonuclease DIS3L2, and the SKI complex-interacting factor Focadhesin (FOCAD) in the context of cancer vulnerability. Using CRISPR and public functional genomics data, we show impairment of cell proliferation upon knockout of TUT7 or DIS3L2, but not TUT4, on cancer cells with FOCAD loss. Moreover, we report the characterization of the first potent and selective TUT4/7 inhibitors that substantially reduce uridylation and demonstrate in vitro and in vivo antiproliferative activity specifically in FOCAD-deleted cancer. FOCAD deficiency post-transcriptionally disrupts the stability of the SKI complex, whose role is to safeguard cells against aberrant RNA. Re-introduction of FOCAD restores the SKI complex and makes these cells less sensitive to TUT4/7 inhibitors, indicating that TUT7 dependency is FOCAD loss-driven. We propose a model where, in absence of FOCAD, TUT7 and DIS3L2 function as a salvage mechanism that degrades aberrant RNA, and genetic or pharmacological inhibition of this pathway leads to cell death. Our findings underscore the significance of FOCAD loss as a genetic driver of TUT7 vulnerability and provide insights into the potential utility of TUT4/7 inhibitors for cancer treatment.
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This study describes decentralized recruitment and enrollment for a COVID-19 treatment trial, while comparing 5 primary recruitment methods: search engine ads, paid advertising within a national testing company, paid advertising within a regional testing company, electronic health record messages, and word of mouth. These are compared across patient demographics, efficiency, and cost. Clinical Trials Registration: NCT04510194.
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BACKGROUND: Postacute sequelae of SARS-CoV-2 infection (PASC) is an increasingly recognized phenomenon and manifested by long-lasting cognitive, mental, and physical symptoms beyond the acute infection period. We aimed to estimate the frequency of PASC symptoms in solid organ transplant (SOT) recipients and compared their frequency between those with SARS-CoV-2 infection requiring hospitalization and those who did not require hospitalization. METHODS: A survey consisting of 7 standardized questionnaires was administered to 111 SOT recipients with history of SARS-CoV-2 infection diagnosed >4 wk before survey administration. RESULTS: Median (interquartile range) time from SARS-CoV-2 diagnosis was 167 d (138-221). Hospitalization for SARS-CoV-2 infection was reported in 33 (30%) participants. Symptoms after the COVID episode were perceived as following: significant trauma (53%), cognitive decline (50%), fatigue (41%), depression (36%), breathing problems (35%), anxiety (23%), dysgeusia (22%), dysosmia (21%), and pain (19%). Hospitalized patients had poorer median scores in cognition (Quick Dementia Rating System survey score: 2.0 versus 0.5, P = 0.02), quality of life (Health-related Quality of Life survey: 2.0 versus 1.0, P = 0.015), physical health (Global physical health scale: 10.0 versus 11.0, P = 0.005), respiratory status (Breathlessness, Cough and Sputum Scale: 1.0 versus 0.0, P = 0.035), and pain (Pain score: 3 versus 0 out of 10, P = 0.003). Among patients with infection >6 mo prior, some symptoms were still present as following: abnormal breathing (42%), cough (40%), dysosmia (29%), and dysgeusia (34%). CONCLUSIONS: SOT recipients reported a high frequency of PASC symptoms. Multidisciplinary approach is needed to care for these patients beyond the acute phase.
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COVID-19 , Transplante de Órgãos , Humanos , Autorrelato , COVID-19/epidemiologia , SARS-CoV-2 , Qualidade de Vida , Teste para COVID-19 , Transplantados , Tosse , Dor , Transplante de Órgãos/efeitos adversosRESUMO
Widespread introduced species can be leveraged to investigate the genetic, ecological and adaptive processes underlying rapid evolution and range expansion, particularly the contributions of genetic diversity to adaptation. Rhinella marina, the cane toad, has been a focus of invasion biology for decades in Australia. However, their introduction history in North America is less clear. Here, we investigated the roles of introduction history and genetic diversity in establishment success of cane toads across their introduced range. We used reduced representation sequencing (ddRAD) to obtain 34,000 SNPs from 247 toads in native (French Guiana, Guyana, Ecuador, Panama, Texas) and introduced (Bermuda, southern Florida, northern Florida, Hawai'i, Puerto Rico) populations. Unlike all other cane toad introductions, we found that Florida populations were more closely related to native Central American lineages (R. horribilis), than to native Southern American lineages (R. marina). Furthermore, we found high levels of diversity and population structure in the native range, corroborating suggestions that R. marina is a species complex. We also found that introduced populations exhibit only slightly lower genetic diversity than native populations. Together with demographic analyses, this indicates founding populations of toads in Florida were larger than previously reported. Lastly, within R. marina, only one of 245 putatively adaptive SNPs showed fixed differences between native and introduced ranges, suggesting that putative selection in these introduced populations is based upon existing genetic variation. Our findings highlight the importance of genetic sequencing in understanding biological introductions and hint at the role of standing genetic variation in range expansion.
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Variação Genética , Espécies Introduzidas , Animais , Bufo marinus/genética , Austrália , Variação Genética/genética , TexasRESUMO
Introduction: Few studies have been published to date exploring the effectiveness of ketamine for treatment-resistant depression (TRD) in large clinical samples. We report on the clinical outcomes of a large cohort treated with ketamine as part of clinical practice.Methods: Deidentified electronic chart data were obtained from a multisite private ketamine infusion clinic for 424 patients with TRD seen from November 9, 2017, to May 4, 2021. Ketamine infusions were administered at a starting dose of 0.5 mg/kg/40 minutes for 6 infusions within 21 days. Maintenance infusions were offered based on clinical response. Changes in outcome measures (scores on the Patient Health Questionnaire-9 [PHQ-9] and Generalized Anxiety Disorder-7 [GAD-7]) within subjects were analyzed using longitudinal multilevel modeling with Kaplan-Meier estimates. Logistic regression was used to analyze for a priori theorized potential moderators of response.Results: Significant improvements from baseline were observed over time on the main outcomes (all P < .001). Based on PHQ-9 self-report data, within 6 weeks of infusion initiation, a 50% response rate and 20% remission rate for depressive symptoms were observed. Response and remission rates were 72% and 38%, respectively, after 10 infusions, and there was a 50% reduction in self-harm/suicidal ideation (SI) symptom scores within 6 weeks. Half of patients with SI at baseline no longer had it after 6 infusions. A 30% reduction in anxiety symptoms (per the GAD-7) was observed.Conclusions: Ketamine was effective at reducing symptoms of SI, depression, and anxiety. The high rates of response and remission were similar to those for interventional treatments in community samples of TRD. Comparative efficacy trials with other interventions and randomized controlled trials of racemic ketamine infusion as the primary treatment for SI are needed.
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Transtorno Depressivo Maior , Ketamina , Ansiedade , Depressão , Transtorno Depressivo Maior/tratamento farmacológico , Humanos , Ketamina/efeitos adversos , Estudos Retrospectivos , Ideação Suicida , Resultado do TratamentoRESUMO
Cocaine use disorder (CUD) patients display heterogenous symptoms and unforeseeable responses to available treatment approaches, highlighting the need to identify objective, accessible biobehavioral signatures to predict clinical trial success in this population. In the present experiments, we employed a task-based behavioral and pharmacogenetic-fMRI approach to address this gap. Craving, an intense desire to take cocaine, can be evoked by exposure to cocaine-associated stimuli which can trigger relapse during attempted recovery. Attentional bias towards cocaine-associated words is linked to enhanced effective connectivity (EC) from the anterior cingulate cortex (ACC) to hippocampus in CUD participants, an observation which was replicated in a new cohort of participants in the present studies. Serotonin regulates attentional bias to cocaine and the serotonergic antagonist mirtazapine decreased activated EC associated with attentional bias, with greater effectiveness in those CUD participants carrying the wild-type 5-HT2CR gene relative to a 5-HT2CR single nucleotide polymorphism (rs6318). These data suggest that the wild-type 5-HT2CR is necessary for the efficacy of mirtazapine to decrease activated EC in CUD participants and that mirtazapine may serve as an abstinence enhancer to mitigate brain substrates of craving in response to cocaine-associated stimuli in participants with this pharmacogenetic descriptor. These results are distinctive in outlining a richer "fingerprint" of the complex neurocircuitry, behavior and pharmacogenetics profile of CUD participants which may provide insight into success of future medications development projects.
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Transtornos Relacionados ao Uso de Cocaína , Cocaína , Transtornos Relacionados ao Uso de Substâncias , Transtornos Relacionados ao Uso de Cocaína/tratamento farmacológico , Transtornos Relacionados ao Uso de Cocaína/genética , Giro do Cíngulo , Humanos , Mirtazapina , SerotoninaRESUMO
BACKGROUND: The US incarcerates more individuals than any other country. Prisoners are the only population guaranteed health care by the US constitution, but little is known about their surgical needs. This multicenter study aimed to describe the acute care surgery (ACS) needs of incarcerated individuals. METHODS: Twelve centers prospectively identified incarcerated patients evaluated in their emergency department by the ACS service. Centers collected diagnosis, treatment, and complications from chart review. Patients were classified as either emergency general surgery (EGS) patients or trauma patients and their characteristics and outcomes were investigated. Poisson regression accounting for clustering by center was used to calculate the relative risk (RR) of readmission, representation within 90 days, and failure to follow-up as an outpatient within 90 days for each cohort. RESULTS: More than 12 months, ACS services evaluated 943 patients, 726 (80.3%) from jail, 156 (17.3%) from prison, and 22 (2.4%) from other facilities. Most were men (89.7%) with a median age of 35 years (interquartile range, 27-47). Trauma patients comprised 54.4% (n = 513) of the cohort. Admission rates were similar for trauma (61.5%) and EGS patients (60.2%). Head injuries and facial fractures were the most common injuries, while infections were the most common EGS diagnosis. Self-harm resulted in 102 trauma evaluations (19.9%). Self-inflicted injuries were associated with increased risk of readmission (RR, 4.3; 95% confidence interval, 3.02-6.13) and reevaluation within 90 days (RR, 4.96; 95% confidence interval, 3.07-8.01). CONCLUSION: Incarcerated patients who present with a range of trauma and EGS conditions frequently require admission, and follow-up after hospitalization was low at the treating center. Poor follow-up coupled with high rates of assault, self-harm, mental health, and substance use disorders highlight the vulnerability of this population. Hospital and correctional facility interventions are needed to decrease self-inflicted injuries and assaults while incarcerated. LEVEL OF EVIDENCE: Prognostic and epidemiological, Level III.
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Serviços Médicos de Emergência , Cirurgia Geral , Prisioneiros , Adulto , Estabelecimentos Correcionais , Cuidados Críticos , Serviço Hospitalar de Emergência , Feminino , Hospitalização , Humanos , MasculinoRESUMO
BACKGROUND: As the first wave of the COVID-19 pandemic stabilized and resources became more readily available, elective surgery was reinitiated and hospitals realized that there was little guidance on how to prioritize elective cases. METHODS: A prioritization tool was formulated based on clinically relevant elements and previous literature. Nine pediatric orthopaedic surgeons from North American institutions evaluated 25 clinical scenarios on 2 occasions separated in time. Intra-rater and inter-rater reliability were calculated [intraclass correlation coefficient (ICC)]. Surgeons also ranked the importance of each element and how confident they were with scoring each factor. RESULTS: Intra-rater ICC for total score showed good to excellent consistency; highest at 0.961 for length of stay (LOS) and lowest at 0.705 for acuity. Inter-rater ICC showed good to excellent agreement for American Society of Anesthesiologists score, LOS, duration of surgery, and transfusion risk and moderate agreement for surgical acuity and personal protective equipment (PPE) use. Transfusion risk and duration of surgery were deemed least important, and surgeons were least confident in scoring PPE and transfusion risk. Based on findings, the novel Elective-Pediatric Orthopedic Surgical Timing (E-POST) score for prioritizing elective cases was developed, consisting of 5 factors: surgical acuity, global health status, LOS, duration of surgery, and PPE requirement. CONCLUSIONS: The E-POST numeric total score or subscore may help objectively prioritize elective cases during a global crisis. LEVEL OF EVIDENCE: Level V.
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COVID-19 , Pandemias , Criança , Procedimentos Cirúrgicos Eletivos , Humanos , Reprodutibilidade dos Testes , SARS-CoV-2RESUMO
PURPOSE: Standard treatment for skeletally immature adolescents with moderate Adolescent Idiopathic Scoliosis (AIS) is a full-time spinal orthosis. However, adherence to full-time wear (≥ 18 h/day) is often challenging for these patients. Nighttime bracing is an alternative option that may improve patient adherence and/or satisfaction. This systematic review and meta-analysis assessed the effectiveness of nighttime bracing in patients with AIS. METHODS: A systematic review of studies evaluating nighttime bracing was performed. PubMed, Medline, Embase, CINAHL and Cochrane library databases were searched (01/1975-03/2020); two reviewers assessed eligibility. Eligible articles were peer reviewed, in English, and reported outcomes for patients who met Scoliosis Research Society (SRS) criteria. The primary outcome was curve progression ≥ 6°. Pooled progression rates were calculated from random effects meta-analyses with inverse-variance weights; 95% CIs were calculated. RESULTS: Nine studies (n = 595) were included. The overall pooled progression rate to ≥ 6° was 40.7% (95% CI: 30.4-51.5%). The pooled progression rate to surgical magnitude was 24.8% (95% CI: 4.5-53.6%). The most successful outcomes were in subjects with thoracolumbar/lumbar curves and subjects who initiated bracing at Risser 1/2 (pooled progression rates were 27.8% (95% CI: 17.0-40.0%) and 16.5% (95% CI: 11.7-21.8%), respectively). Univariate sub-analyses were conducted due to sample sizes. CONCLUSIONS: Progression rates in patients with primary thoracolumbar/lumbar curves and in patients who initiated nighttime bracing at Risser 1/2 were comparable to published progression rates for full-time bracing, indicating that nighttime bracing may be equally effective for these patients. However, the strength of these conclusions is limited by the sample size and the overall quality of included studies.
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Cifose , Procedimentos Ortopédicos , Escoliose , Adolescente , Braquetes , Humanos , Guias de Prática Clínica como Assunto , Escoliose/terapia , Resultado do TratamentoRESUMO
Background: Severe innate immune suppression, termed immunoparalysis, is associated with increased risks of nosocomial infection and mortality in children with septic shock. Currently, immunoparalysis cannot be clinically diagnosed in children, and mechanisms remain unclear. Transcriptomic studies identify subsets of septic children with downregulation of genes within adaptive immune pathways, but assays of immune function have not been performed as part of these studies, and little is known about transcriptomic profiles of children with immunoparalysis. Methods: We performed a nested case-control study to identify differences in RNA expression patterns between children with septic shock with immunoparalysis (defined as lipopolysaccharide (LPS)-induced tumor necrosis factor (TNF)α response < 200 pg/ml) vs those with normal LPS-induced TNFα response. Children were enrolled within 48 hours of the onset of septic shock and divided into two groups based on LPS-induced TNFα response. RNA was extracted from whole blood for RNAseq, differential expression analyses using DESeq2 software, and pathway analyses using Ingenuity Pathway Analysis. Results: 32 children were included in analyses. Comparing those with immunoparalysis (n =19) to those with normal TNFα response (n = 13), 2,303 transcripts were differentially expressed with absolute value fold change ≥ 1.5 and false discovery rate ≤ 0.05. The majority of downregulated pathways in children with immunoparalysis were pathways that involved interactions between innate and adaptive immune cells necessary for cell-mediated immunity, crosstalk between dendritic cells and natural killer cells, and natural killer cell signaling pathways. Upregulated pathways included those involved in humoral immunity (T helper cell type 2), corticotropin signaling, platelet activation (GP6 signaling), and leukocyte migration and extravasation. Conclusions: Our study suggests that gene expression data might be useful to identify children with immunoparalysis and identifies several key differentially regulated pathways involved in both innate and adaptive immunity. Our ongoing work in this area aims to dissect interactions between innate and adaptive immunity in septic children and to more fully elucidate patient-specific immunologic pathophysiology to guide individualized immunotherapeutic targets.
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Células Dendríticas/fisiologia , Choque Séptico/imunologia , Células Th2/imunologia , Imunidade Adaptativa/genética , Adolescente , Estudos de Casos e Controles , Criança , Pré-Escolar , Infecção Hospitalar , Feminino , Perfilação da Expressão Gênica , Humanos , Tolerância Imunológica , Imunidade Inata/genética , Lipopolissacarídeos/imunologia , Masculino , Choque Séptico/genética , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/metabolismoRESUMO
Dynamic causal modeling (DCM) is a method for analyzing functional magnetic resonance imaging (fMRI) and other functional neuroimaging data that provides information about directionality of connectivity between brain regions. A review of the neuropsychiatric fMRI DCM literature suggests that there may be a historical trend to under-report self-connectivity (within brain regions) compared to between brain region connectivity findings. These findings are an integral part of the neurologic model represented by DCM and serve an important neurobiological function in regulating excitatory and inhibitory activity between regions. We reviewed the literature on the topic as well as the past 13 years of available neuropsychiatric DCM literature to find an increasing (but still, perhaps, and inadequate) trend in reporting these results. The focus of this review is fMRI as the majority of published DCM studies utilized fMRI and the interpretation of the self-connectivity findings may vary across imaging methodologies. About 25% of articles published between 2007 and 2019 made any mention of self-connectivity findings. We recommend increased attention toward the inclusion and interpretation of self-connectivity findings in DCM analyses in the neuropsychiatric literature, particularly in forthcoming effective connectivity studies of substance use disorders.
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Past investigations utilizing diffusion tensor imaging (DTI) have demonstrated that cocaine use disorder (CUD) yields white matter changes, primarily in the corpus callosum. By applying Bayesian model averaging using multiple linear regression in DTI, we demonstrate there may exist relationships between the impaired white matter and glutamic acid decarboxylase (GAD) polymorphisms. This work explored the two-way and three-way interactions between GAD1a (SNP: rs1978340) and GAD1b (SNP: rs769390) polymorphisms and years of cocaine use (YCU). GAD1a was associated with more frontal white matter changes on its own but GAD1b was associated with more midbrain and cerebellar changes as well as a greater increase in white matter changes in the context of chronic cocaine use. The three-way interaction GAD1a|GAD1b|YCU appeared to be roughly an average of the polymorphism two-way interactions GAD1a|YCU and GAD1b|YCU. The three-way interaction demonstrated multiple regions including corpus callosum which featured fewer significant voxel changes, perhaps suggesting a small protective effect of having both polymorphisms on corpus callosum and cerebellar peduncle.
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Transtornos Relacionados ao Uso de Cocaína/genética , Cocaína/efeitos adversos , Predisposição Genética para Doença , Glutamato Descarboxilase/genética , Substância Branca/diagnóstico por imagem , Adulto , Teorema de Bayes , Encéfalo/diagnóstico por imagem , Encéfalo/efeitos dos fármacos , Cerebelo/diagnóstico por imagem , Cerebelo/efeitos dos fármacos , Transtornos Relacionados ao Uso de Cocaína/epidemiologia , Transtornos Relacionados ao Uso de Cocaína/patologia , Corpo Caloso/diagnóstico por imagem , Corpo Caloso/efeitos dos fármacos , Imagem de Tensor de Difusão , Feminino , Estudos de Associação Genética , Humanos , Masculino , Pessoa de Meia-Idade , Substância Branca/efeitos dos fármacos , Adulto JovemRESUMO
BACKGROUND: Abnormalities of reward sensitivity and impulsivity are known to be correlated with each other and alcohol use disorder (AUD) risk, but the underlying aberrant neural circuitry involved is not clearly defined. We sought to extend the current knowledge of AUD pathophysiology by studying incentive processing in persons with AUD using functional neuroimaging data. METHODS: We utilized functional MRI data from the Human Connectome Project Database obtained during performance of a number-guessing incentive-processing task with win, loss, and neutral feedback conditions in 78 participants with either DSM-IV alcohol abuse or dependence (combined as the AUD group) and 78 age- and sex-matched control (CON) participants. Within a network consisting of anterior cingulate cortex (ACC), dorsolateral prefrontal cortex (DLPFC), insula, ventral striatum, and dorsal striatum (DS) in the right hemisphere, we performed dynamic causal modeling analysis to test group-level differences (AUD vs. CON) in effective directional connectivity (EC) as modulated by "win" and "loss" conditions. We used linear regression analyses to characterize the relations between each EC outcome and measures of cumulative alcohol exposure and impulsivity. RESULTS: During wins, AUD participants had lower ECs from ACC to the other four nodes, greater ECs from insula to the other four nodes, greater ECs from DLPFC to the other four nodes, and greater DS to DS self-connection EC than CON participants. In the total sample, EC from the insula to the DLPFC (insula â DLPFC) during wins was positively correlated with both impulsivity (as measured by the delay-discounting task) and cumulative alcohol exposure. The DS to DS self-connection EC during wins was positively correlated with impulsivity. Many of the altered ECs from the ACC and insula to other nodes were correlated with cumulative alcohol exposure. CONCLUSIONS: Individuals with AUD have disrupted EC in both instrumentally driven and automatized corticostriatal reward circuits during non-alcohol reward feedback. These results point to disrupted corticostriatal EC in both "top-down" and "bottom-up" pathways among individuals with AUD.
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Alcoolismo/fisiopatologia , Córtex Cerebral/fisiopatologia , Corpo Estriado/fisiopatologia , Desvalorização pelo Atraso/fisiologia , Adulto , Alcoolismo/diagnóstico por imagem , Alcoolismo/psicologia , Estudos de Casos e Controles , Córtex Cerebral/diagnóstico por imagem , Corpo Estriado/diagnóstico por imagem , Feminino , Humanos , Comportamento Impulsivo , Imageamento por Ressonância Magnética , Masculino , RecompensaRESUMO
The human hs1.2 enhancer within the Ig heavy chain gene (IGH) is polymorphic and associated with a number of autoimmune diseases. The polymorphic region is characterized by tandem repeats of an â¼53-bp invariant sequence containing possible binding sites for several transcription factors. Our previous studies suggest the human hs1.2 enhancer is sensitive to 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), an environmental toxicant and high affinity ligand of the aryl hydrocarbon receptor (AhR). TCDD induced hs1.2 enhancer activity in an AhR-dependent manner and the number of invariant sequences influenced the magnitude of activity. To better understand the regulation of human hs1.2 enhancer activity, the objective of the current study was to utilize mutational analysis and luciferase reporter constructs to evaluate the contribution of putative transcription factor binding sites to overall hs1.2 enhancer activity and modulation by TCDD. Basal and LPS-induced activity of the hs1.2 enhancer appeared to be most affected by mutation of sites outside of the invariant sequence or deletion of the entire invariant sequence; whereas sites influencing the effect of TCDD were dependent on the cellular activation state (i.e. unstimulated vs. LPS stimulation) and relatively independent of the putative AhR binding site within the invariant sequence. These results suggest that AhR activation affects human hs1.2 activity through an as yet undetermined non-canonical pathway. A better understanding regarding the role of the hs1.2 enhancer in human Ig expression and how AhR ligands modulate its activity may lead to insights into overall Ig regulation and mechanisms of dysfunction.
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Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Genes de Cadeia Pesada de Imunoglobulina , Receptores de Hidrocarboneto Arílico/metabolismo , Animais , Sequência de Bases , Fatores de Transcrição Hélice-Alça-Hélice Básicos/química , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Sítios de Ligação/genética , Linhagem Celular , Elementos Facilitadores Genéticos/efeitos dos fármacos , Humanos , Camundongos , Mutagênese Sítio-Dirigida , Mutação , Dibenzodioxinas Policloradas/metabolismo , Dibenzodioxinas Policloradas/toxicidade , Receptores de Hidrocarboneto Arílico/química , Receptores de Hidrocarboneto Arílico/genética , Ativação Transcricional/efeitos dos fármacosRESUMO
The activity of the transcription factor nuclear factor-erythroid 2 p45-derived factor 2 (NRF2) is orchestrated and amplified through enhanced transcription of antioxidant and antiinflammatory target genes. The present study has characterized a triazole-containing inducer of NRF2 and elucidated the mechanism by which this molecule activates NRF2 signaling. In a highly selective manner, the compound covalently modifies a critical stress-sensor cysteine (C151) of the E3 ligase substrate adaptor protein Kelch-like ECH-associated protein 1 (KEAP1), the primary negative regulator of NRF2. We further used this inducer to probe the functional consequences of selective activation of NRF2 signaling in Huntington's disease (HD) mouse and human model systems. Surprisingly, we discovered a muted NRF2 activation response in human HD neural stem cells, which was restored by genetic correction of the disease-causing mutation. In contrast, selective activation of NRF2 signaling potently repressed the release of the proinflammatory cytokine IL-6 in primary mouse HD and WT microglia and astrocytes. Moreover, in primary monocytes from HD patients and healthy subjects, NRF2 induction repressed expression of the proinflammatory cytokines IL-1, IL-6, IL-8, and TNFα. Together, our results demonstrate a multifaceted protective potential of NRF2 signaling in key cell types relevant to HD pathology.
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Doença de Huntington/metabolismo , Proteína 1 Associada a ECH Semelhante a Kelch/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo , Adulto , Idoso , Animais , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Células Cultivadas , Citocinas/metabolismo , Modelos Animais de Doenças , Feminino , Células HEK293 , Humanos , Doença de Huntington/genética , Proteína 1 Associada a ECH Semelhante a Kelch/química , Intoxicação por MPTP/metabolismo , Intoxicação por MPTP/prevenção & controle , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Microglia/efeitos dos fármacos , Microglia/metabolismo , Pessoa de Meia-Idade , Fator 2 Relacionado a NF-E2/química , Células-Tronco Neurais/metabolismo , Fármacos Neuroprotetores/farmacologia , Conformação Proteica/efeitos dos fármacos , Ratos , Transdução de SinaisRESUMO
Inhibitor of DNA binding or inhibitor of differentiation (Id) proteins are up regulated in a variety of neoplasms, particularly in association with high-grade, poorly differentiated tumors, while differentiated tissues show little or no Id expression. The four Id genes are members of the helix-loop-helix (HLH) family of transcription factors and act as negative regulators of transcription by binding to and sequestering HLH complexes. We tested the hypothesis that Id proteins are overexpressed in medulloblastoma by performing immunohistochemistry using a medulloblastoma tissue microarray with 45 unique medulloblastoma and 11 normal control cerebella, and antibodies specific for Id1, Id2, Id3, and Id4. A semi-quantitative staining score that took staining intensity and the proportion of immunoreactive cells into account was used. Id1 was not detected in normal cerebella or in medulloblastoma cells, but 78 % of tumors showed strong Id1 expression in endothelial nuclei of tumor vessels. Id2 expression was scant in normal cerebella and increased in medulloblastoma (median staining score: 4). Id3 expression was noted in some neurons of the developing cerebellar cortex, but it was markedly up regulated in medulloblastoma (median staining score: 12) and in tumor endothelial cells. Id4 was not expressed in normal cerebella or in tumor cells. Id2 or Id3 overexpression drove proliferation in medulloblastoma cell lines by altering the expression of critical cell cycle regulatory proteins in favor of cell proliferation. This study shows that Id1 expression in endothelial cells may contribute to angiogenic processes and that increased expression of Id2 and Id3 in medulloblastoma is potentially involved in tumor cell proliferation and survival.
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Neoplasias Cerebelares/metabolismo , Proteínas Inibidoras de Diferenciação/biossíntese , Meduloblastoma/metabolismo , Adolescente , Linhagem Celular Tumoral , Cerebelo/metabolismo , Criança , Pré-Escolar , Quinases Ciclina-Dependentes/metabolismo , Feminino , Humanos , Imuno-Histoquímica , Lactente , Masculino , Especificidade de Órgãos , Estatísticas não ParamétricasRESUMO
Myotubular myopathy (MTM) is a severe congenital muscle disease characterized by profound weakness, early respiratory failure and premature lethality. MTM is defined by muscle biopsy findings that include centralized nuclei and disorganization of perinuclear organelles. No treatments currently exist for MTM. We hypothesized that aberrant neuromuscular junction (NMJ) transmission is an important and potentially treatable aspect of the disease pathogenesis. We tested this hypothesis in two murine models of MTM. In both models we uncovered evidence of a disorder of NMJ transmission: fatigable weakness, improved strength with neostigmine, and electrodecrement with repetitive nerve stimulation. Histopathological analysis revealed abnormalities in the organization, appearance and size of individual NMJs, abnormalities that correlated with changes in acetylcholine receptor gene expression and subcellular localization. We additionally determined the ability of pyridostigmine, an acetylcholinesterase inhibitor, to ameliorate aspects of the behavioral phenotype related to NMJ dysfunction. Pyridostigmine treatment resulted in significant improvement in fatigable weakness and treadmill endurance. In all, these results describe a newly identified pathological abnormality in MTM, and uncover a potential disease-modifying therapy for this devastating disorder.