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1.
Proc Natl Acad Sci U S A ; 119(4)2022 01 25.
Artículo en Inglés | MEDLINE | ID: mdl-35074918

RESUMEN

MeCP2 is associated with Rett syndrome (RTT), MECP2 duplication syndrome, and a number of conditions with isolated features of these diseases, including autism, intellectual disability, and motor dysfunction. MeCP2 is known to broadly bind methylated DNA, but the precise molecular mechanism driving disease pathogenesis remains to be determined. Using proximity-dependent biotinylation (BioID), we identified a transcription factor 20 (TCF20) complex that interacts with MeCP2 at the chromatin interface. Importantly, RTT-causing mutations in MECP2 disrupt this interaction. TCF20 and MeCP2 are highly coexpressed in neurons and coregulate the expression of key neuronal genes. Reducing Tcf20 partially rescued the behavioral deficits caused by MECP2 overexpression, demonstrating a functional relationship between MeCP2 and TCF20 in MECP2 duplication syndrome pathogenesis. We identified a patient exhibiting RTT-like neurological features with a missense mutation in the PHF14 subunit of the TCF20 complex that abolishes the MeCP2-PHF14-TCF20 interaction. Our data demonstrate the critical role of the MeCP2-TCF20 complex for brain function.


Asunto(s)
Proteína 2 de Unión a Metil-CpG/metabolismo , Complejos Multiproteicos/metabolismo , Trastornos del Neurodesarrollo/etiología , Trastornos del Neurodesarrollo/metabolismo , Factores de Transcripción/metabolismo , Alelos , Animales , Biomarcadores , Encéfalo/metabolismo , Modelos Animales de Enfermedad , Susceptibilidad a Enfermedades , Proteína 2 de Unión a Metil-CpG/genética , Ratones , Ratones Noqueados , Ratones Transgénicos , Modelos Biológicos , Mutación , Neuronas/metabolismo , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Unión Proteica , Sinapsis/metabolismo , Factores de Transcripción/genética
2.
Hum Mol Genet ; 29(5): 705-715, 2020 03 27.
Artículo en Inglés | MEDLINE | ID: mdl-31600777

RESUMEN

Bosch-Boonstra-Schaaf optic atrophy syndrome (BBSOAS) has been identified as an autosomal-dominant disorder characterized by a complex neurological phenotype, with high prevalence of intellectual disability and optic nerve atrophy/hypoplasia. The syndrome is caused by loss-of-function mutations in NR2F1, which encodes a highly conserved nuclear receptor that serves as a transcriptional regulator. Previous investigations to understand the protein's role in neurodevelopment have mostly used mouse models with constitutive and tissue-specific homozygous knockout of Nr2f1. In order to represent the human disease more accurately, which is caused by heterozygous NR2F1 mutations, we investigated a heterozygous knockout mouse model and found that this model recapitulates some of the neurological phenotypes of BBSOAS, including altered learning/memory, hearing defects, neonatal hypotonia and decreased hippocampal volume. The mice showed altered fear memory, and further electrophysiological investigation in hippocampal slices revealed significantly reduced long-term potentiation and long-term depression. These results suggest that a deficit or alteration in hippocampal synaptic plasticity may contribute to the intellectual disability frequently seen in BBSOAS. RNA-sequencing (RNA-Seq) analysis revealed significant differential gene expression in the adult Nr2f1+/- hippocampus, including the up-regulation of multiple matrix metalloproteases, which are known to be critical for the development and the plasticity of the nervous system. Taken together, our studies highlight the important role of Nr2f1 in neurodevelopment. The discovery of impaired hippocampal synaptic plasticity in the heterozygous mouse model sheds light on the pathophysiology of altered memory and cognitive function in BBSOAS.


Asunto(s)
Factor de Transcripción COUP I/fisiología , Depresión/patología , Hipocampo/patología , Trastornos de la Memoria/patología , Plasticidad Neuronal , Atrofias Ópticas Hereditarias/patología , Animales , Conducta Animal , Depresión/etiología , Depresión/metabolismo , Femenino , Hipocampo/metabolismo , Masculino , Trastornos de la Memoria/etiología , Trastornos de la Memoria/metabolismo , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Atrofias Ópticas Hereditarias/etiología , Atrofias Ópticas Hereditarias/metabolismo
3.
MMWR Morb Mortal Wkly Rep ; 71(11): 422-428, 2022 Mar 18.
Artículo en Inglés | MEDLINE | ID: mdl-35298453

RESUMEN

The BNT162b2 (Pfizer-BioNTech) mRNA COVID-19 vaccine was recommended by CDC's Advisory Committee on Immunization Practices for persons aged 12-15 years (referred to as adolescents in this report) on May 12, 2021, and for children aged 5-11 years on November 2, 2021 (1-4). Real-world data on vaccine effectiveness (VE) in these age groups are needed, especially because when the B.1.1.529 (Omicron) variant became predominant in the United States in December 2021, early investigations of VE demonstrated a decline in protection against symptomatic infection for adolescents aged 12-15 years and adults* (5). The PROTECT† prospective cohort of 1,364 children and adolescents aged 5-15 years was tested weekly for SARS-CoV-2, irrespective of symptoms, and upon COVID-19-associated illness during July 25, 2021-February 12, 2022. Among unvaccinated participants (i.e., those who had received no COVID-19 vaccine doses) with any laboratory-confirmed SARS-CoV-2 infection, those with B.1.617.2 (Delta) variant infections were more likely to report COVID-19 symptoms (66%) than were those with Omicron infections (49%). Among fully vaccinated children aged 5-11 years, VE against any symptomatic and asymptomatic Omicron infection 14-82 days (the longest interval after dose 2 in this age group) after receipt of dose 2 of the Pfizer-BioNTech vaccine was 31% (95% CI = 9%-48%), adjusted for sociodemographic characteristics, health information, frequency of social contact, mask use, location, and local virus circulation. Among adolescents aged 12-15 years, adjusted VE 14-149 days after dose 2 was 87% (95% CI = 49%-97%) against symptomatic and asymptomatic Delta infection and 59% (95% CI = 22%-79%) against Omicron infection. Fully vaccinated participants with Omicron infection spent an average of one half day less sick in bed than did unvaccinated participants with Omicron infection. All eligible children and adolescents should remain up to date with recommended COVID-19 vaccinations.


Asunto(s)
Vacuna BNT162/administración & dosificación , Vacuna BNT162/uso terapéutico , COVID-19/prevención & control , SARS-CoV-2/inmunología , Eficacia de las Vacunas , Adolescente , Niño , Preescolar , Estudios de Cohortes , Femenino , Humanos , Masculino , Estudios Prospectivos , Estados Unidos
4.
Am J Gastroenterol ; 109(6): 867-75, 2014 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-24732869

RESUMEN

OBJECTIVES: Adherence to the American Association for the Study of Liver Disease (AASLD) guidelines for the management of chronic hepatitis B (CHB) has not been systematically assessed. We sought to comprehensively evaluate adherence to five key areas of these guidelines. We also evaluated physician and patient factors underlying nonadherence, and predictors of nonadherence such as physician type, patient demographic factors, and phase of CHB infection. METHODS: Nine hundred and sixty-two adult patients were retrospectively identified. Each patient chart was reviewed in detail. The primary outcome was adherence to five areas of the AASLD guidelines: (i) timely alanine aminotransferase (ALT)/hepatitis B virus DNA level checks needed to monitor inactive carrier and immune-tolerant phases; (ii) liver biopsy to guide decisions on initiating treatment; (iii) treatment initiation when indicated; (iv) hepatocellular carcinoma (HCC) screening; (v) testing for hepatitis A virus (HAV) immunity, HIV, and hepatitis C virus (HCV) co-infections. RESULTS: Sixty percent did not undergo clinically indicated liver biopsies, largely owing to physician nonadherence. Eighty-nine percent of these missed biopsies were needed to further assess possible e-antigen-negative CHB. A high treatment initiation rate was found for the treatment eligible, but 121 patients had unclear treatment eligibility as they warranted, but did not undergo, liver biopsy. Forty-five percent did not have timely HCC screening, although gastroenterology physicians had the highest odds of adherence, and 29% did not have timely CHB lab assessment; patients seen by gastroenterologists had twice the odds compared with primary care physicians of undergoing timely lab monitoring. Thirty-five, 24, and 54% were not tested for HAV, HCV, and HIV co-infections. CONCLUSIONS: Our findings show remarkably poor adherence to AASLD guidelines, particularly in the areas of liver biopsy, timely HCC and ALT monitoring, and testing for co-infection. These findings call for greater efforts to meet physician knowledge gaps, incorporation of decision support tools, and improved communication among providers.


Asunto(s)
Antivirales/uso terapéutico , Adhesión a Directriz/estadística & datos numéricos , Hepatitis B Crónica/tratamiento farmacológico , Pautas de la Práctica en Medicina/estadística & datos numéricos , Centros Médicos Académicos , Adulto , Anciano , Alanina Transaminasa , Biopsia , ADN Viral , Femenino , Hepatitis B Crónica/diagnóstico , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos
5.
Therap Adv Gastroenterol ; 15: 17562848221079162, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35356362

RESUMEN

Background: The impact of social determinants of health in inflammatory bowel disease (IBD) remains understudied. We evaluated the impact of social barriers on IBD outcomes within a diverse cohort of patients. Methods: We performed a cross-sectional study on adult IBD patients and assessed known social determinants of health. We calculated the total prevalence of these barriers in the sample as a whole and within each ethnic group. We summed the number of barriers present for each individual to create a cumulative social barrier score (SBS), and we evaluated the relationship of each barrier and of the cumulative SBS with IBD outcomes, including disease activity and depressive symptoms. Results: A total of 316 patients were included in the study. Disparities in the prevalence of social barriers emerged by ethnicity: non-Hispanic Blacks reported the greatest number of social barriers, followed by Hispanic patients. Prevalent social barriers included financial strains (38.4%), such as food insecurity, medical care delays (~30%), and low educational attainment (26.8%). Social barriers associated with poor IBD outcomes included low educational attainment, poor health literacy, and financial insecurity. High SBS was associated with greater depressive symptoms [odds ratio (OR) 1.94, 95% confidence interval (CI) 1.21-2.9, p = 0.001] and lower reported use of medications. Greater ulcerative colitis (UC) disease activity was observed in patients with greater SBS. No associations were identified between SBS and IBD surgeries, hospitalizations, or disease location. Conclusion: Our study identifies social barriers that may impact IBD care and are disproportionately higher in non-Hispanic Blacks and Hispanics in the United States. Future studies should focus on implementing interventions to reduce these barriers and improve delivery of care.

6.
JMIR Res Protoc ; 11(7): e37929, 2022 Jul 28.
Artículo en Inglés | MEDLINE | ID: mdl-35635842

RESUMEN

BACKGROUND: Assessing the real-world effectiveness of COVID-19 vaccines and understanding the incidence and severity of SARS-CoV-2 illness in children are essential to inform policy and guide health care professionals in advising parents and caregivers of children who test positive for SARS-CoV-2. OBJECTIVE: This report describes the objectives and methods for conducting the Pediatric Research Observing Trends and Exposures in COVID-19 Timelines (PROTECT) study. PROTECT is a longitudinal prospective pediatric cohort study designed to estimate SARS-CoV-2 incidence and COVID-19 vaccine effectiveness (VE) against infection among children aged 6 months to 17 years, as well as differences in SARS-CoV-2 infection and vaccine response between children and adolescents. METHODS: The PROTECT multisite network was initiated in July 2021, which aims to enroll approximately 2305 children across four US locations and collect data over a 2-year surveillance period. The enrollment target was based on prospective power calculations and accounts for expected attrition and nonresponse. Study sites recruit parents and legal guardians of age-eligible children participating in the existing Arizona Healthcare, Emergency Response, and Other Essential Workers Surveillance (HEROES)-Research on the Epidemiology of SARS-CoV-2 in Essential Response Personnel (RECOVER) network as well as from surrounding communities. Child demographics, medical history, COVID-19 exposure, vaccination history, and parents/legal guardians' knowledge and attitudes about COVID-19 are collected at baseline and throughout the study. Mid-turbinate nasal specimens are self-collected or collected by parents/legal guardians weekly, regardless of symptoms, for SARS-CoV-2 and influenza testing via reverse transcription-polymerase chain reaction (RT-PCR) assay, and the presence of COVID-like illness (CLI) is reported. Children who test positive for SARS-CoV-2 or influenza, or report CLI are monitored weekly by online surveys to report exposure and medical utilization until no longer ill. Children, with permission of their parents/legal guardians, may elect to contribute blood at enrollment, following SARS-CoV-2 infection, following COVID-19 vaccination, and at the end of the study period. PROTECT uses electronic medical record (EMR) linkages where available, and verifies COVID-19 and influenza vaccinations through EMR or state vaccine registries. RESULTS: Data collection began in July 2021 and is expected to continue through the spring of 2023. As of April 13, 2022, 2371 children are enrolled in PROTECT. Enrollment is ongoing at all study sites. CONCLUSIONS: As COVID-19 vaccine products are authorized for use in pediatric populations, PROTECT study data will provide real-world estimates of VE in preventing infection. In addition, this prospective cohort provides a unique opportunity to further understand SARS-CoV-2 incidence, clinical course, and key knowledge gaps that may inform public health. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): RR1-10.2196/37929.

7.
Elife ; 92020 03 11.
Artículo en Inglés | MEDLINE | ID: mdl-32159514

RESUMEN

Methylated cytosine is an effector of epigenetic gene regulation. In the brain, Dnmt3a is the sole 'writer' of atypical non-CpG methylation (mCH), and MeCP2 is the only known 'reader' for mCH. We asked if MeCP2 is the sole reader for Dnmt3a dependent methylation by comparing mice lacking either protein in GABAergic inhibitory neurons. Loss of either protein causes overlapping and distinct features from the behavioral to molecular level. Loss of Dnmt3a causes global loss of mCH and a subset of mCG sites resulting in more widespread transcriptional alterations and severe neurological dysfunction than MeCP2 loss. These data suggest that MeCP2 is responsible for reading only part of the Dnmt3a dependent methylation in the brain. Importantly, the impact of MeCP2 on genes differentially expressed in both models shows a strong dependence on mCH, but not Dnmt3a dependent mCG, consistent with mCH playing a central role in the pathogenesis of Rett Syndrome.


Asunto(s)
ADN (Citosina-5-)-Metiltransferasas/metabolismo , Neuronas GABAérgicas/fisiología , Regulación del Desarrollo de la Expresión Génica/fisiología , Proteína 2 de Unión a Metil-CpG/metabolismo , Síndrome de Rett/metabolismo , Animales , ADN (Citosina-5-)-Metiltransferasas/genética , ADN Metiltransferasa 3A , Femenino , Predisposición Genética a la Enfermedad , Masculino , Proteína 2 de Unión a Metil-CpG/genética , Ratones , Síndrome de Rett/genética
8.
Elife ; 82019 09 16.
Artículo en Inglés | MEDLINE | ID: mdl-31524598

RESUMEN

Neurexophilins are secreted neuropeptide-like glycoproteins, and neurexophilin1 and neurexophilin3 are ligands for the presynaptic cell adhesion molecule α-neurexin. Neurexophilins are more selectively expressed in the brain than α-neurexins, however, which led us to ask whether neurexophilins modulate the function of α-neurexin in a context-specific manner. We characterized the expression and function of neurexophilin4 in mice and found it to be expressed in subsets of neurons responsible for feeding, emotion, balance, and movement. Deletion of Neurexophilin4 caused corresponding impairments, most notably in motor learning and coordination. We demonstrated that neurexophilin4 interacts with α-neurexin and GABAARs in the cerebellum. Loss of Neurexophilin4 impaired cerebellar Golgi-granule inhibitory neurotransmission and synapse number, providing a partial explanation for the motor learning and coordination deficits observed in the Neurexophilin4 null mice. Our data illustrate how selectively expressed Neurexophilin4, an α-neurexin ligand, regulates specific synapse function and modulates cerebellar motor control.


Asunto(s)
Cerebelo/fisiología , Glicoproteínas/metabolismo , Actividad Motora , Neuronas Motoras/fisiología , Neuropéptidos/metabolismo , Animales , Eliminación de Gen , Regulación de la Expresión Génica , Glicoproteínas/deficiencia , Ratones Endogámicos C57BL , Ratones Noqueados , Neuropéptidos/deficiencia
9.
Gastroenterol Hepatol (N Y) ; 12(6): 374-9, 2016 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-27493597

RESUMEN

The gut bacterial microbiome, particularly its role in disease and inflammation, has gained international attention with the successful use of fecal microbiota transplantation (FMT) in the treatment of Clostridium difficile infection. This success has led to studies exploring the role of FMT in other conditions, including inflammatory bowel disease (IBD). Both Crohn's disease and ulcerative colitis are chronic inflammatory conditions of the gastrointestinal system that have multifactorial etiologies. A shift in gut microbial composition in genetically susceptible individuals, an altered immune system, and environmental factors are all hypothesized to have a role in the pathogenesis of IBD. While numerous case reports and cohort studies have described the use of FMT in patients with IBD over the last 2 decades, the development of new sequencing techniques and results from 2 recent randomized, controlled trials have allowed for a better understanding of the relationship between the microbiome and the human host. However, despite these efforts, knowledge remains limited and the role of FMT in the management of IBD remains uncertain. Further investigation is necessary before FMT joins the current armamentarium of treatment options in clinical practice.

10.
Inflamm Bowel Dis ; 20(7): 1236-41, 2014 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-24859297

RESUMEN

BACKGROUND: Crohn's disease (CD) requires surgical management in up to two-thirds of patients. Few studies have addressed the issue of ileal recurrence after colectomy and permanent ileostomy. The aims of our study were to assess the rate and predictors of postoperative recurrence of CD in patients with permanent ileostomy. METHODS: In a retrospective study from a tertiary referral center, we analyzed the natural history of patients with CD who underwent total colectomy and permanent ileostomy. Our primary outcomes were (1) overall disease recurrence including luminal recurrence, perianal disease or peristomal lesions requiring therapy, and (2) luminal recurrence alone defined as endoscopic and clinical recurrence within the terminal ileum. We examined if patient characteristics predicted recurrence using multivariate Cox proportional hazard models. RESULTS: Our study included 73 patients with CD followed for a mean of 28 months (range, 0-168 mo) after total colectomy and permanent ileostomy. Twenty patients had overall disease recurrence within 10 years after surgery, at rates of 15% and 50% at 1 and 5 years, respectively. Rate of luminal recurrence was 8% and 35% at 1 and 5 years, respectively. Diagnosis at age less than 18 years (hazard ratio, 2.94; 95% confidence interval, 1.14-7.62) and anti-tumor necrosis factor therapy before surgery (hazard ratio, 4.75; 95% confidence interval, 1.25-18.13) were the only independent predictive factors for overall disease recurrence. CONCLUSIONS: Up to one-third of patients with CD have overall recurrence of disease after treatment with total colectomy and permanent ileostomy. There is need to develop algorithms for surveillance and management of this select subgroup of patients.


Asunto(s)
Colectomía/métodos , Enfermedad de Crohn/diagnóstico , Enfermedad de Crohn/cirugía , Ileostomía/métodos , Adulto , Estudios de Cohortes , Intervalos de Confianza , Enfermedad de Crohn/mortalidad , Progresión de la Enfermedad , Femenino , Estudios de Seguimiento , Humanos , Estimación de Kaplan-Meier , Masculino , Persona de Mediana Edad , Análisis Multivariante , Valor Predictivo de las Pruebas , Modelos de Riesgos Proporcionales , Recurrencia , Estudios Retrospectivos , Medición de Riesgo , Índice de Severidad de la Enfermedad , Análisis de Supervivencia , Centros de Atención Terciaria , Factores de Tiempo , Resultado del Tratamiento , Adulto Joven
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