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1.
EMBO Rep ; 24(1): e55429, 2023 01 09.
Artículo en Inglés | MEDLINE | ID: mdl-36382770

RESUMEN

Developing B cells generate DNA double-stranded breaks (DSBs) to assemble immunoglobulin receptor (Ig) genes necessary for the expression of a mature B cell receptor. These physiologic DSBs are made by the RAG endonuclease, which is comprised of the RAG1 and RAG2 proteins. In pre-B cells, RAG-mediated DSBs activate the ATM kinase to coordinate canonical and non-canonical DNA damage responses (DDR) that trigger DSB repair and B cell developmental signals, respectively. Whether this broad cellular response is distinctive to RAG DSBs is poorly understood. To delineate the factors that direct DDR signaling in B cells, we express a tetracycline-inducible Cas9 nuclease in Rag1-deficient pre-B cells. Both RAG- and Cas9-mediated DSBs at Ig genes activate canonical DDR. In contrast, RAG DSBs, but not Cas9 DSBs, induce the non-canonical DDR-dependent developmental program. This unique response to RAG DSBs is, in part, regulated by non-core regions of RAG1. Thus, B cells trigger distinct cellular responses to RAG DSBs through unique properties of the RAG endonuclease that promotes activation of B cell developmental programs.


Asunto(s)
Roturas del ADN de Doble Cadena , Proteínas de Homeodominio , Proteínas de Homeodominio/genética , Proteínas de Homeodominio/metabolismo , Linfocitos B/metabolismo , Transducción de Señal , Células Precursoras de Linfocitos B , Daño del ADN
2.
J Immunol ; 210(7): 991-1003, 2023 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-36881882

RESUMEN

Checkpoint blockade immunotherapy has failed in pancreatic cancer and other poorly responsive tumor types in part due to inadequate T cell priming. Naive T cells can receive costimulation not only via CD28 but also through TNF superfamily receptors that signal via NF-κB. Antagonists of the ubiquitin ligases cellular inhibitor of apoptosis protein (cIAP)1/2, also called second mitochondria-derived activator of caspases (SMAC) mimetics, induce degradation of cIAP1/2 proteins, allowing for the accumulation of NIK and constitutive, ligand-independent activation of alternate NF-κB signaling that mimics costimulation in T cells. In tumor cells, cIAP1/2 antagonists can increase TNF production and TNF-mediated apoptosis; however, pancreatic cancer cells are resistant to cytokine-mediated apoptosis, even in the presence of cIAP1/2 antagonism. Dendritic cell activation is enhanced by cIAP1/2 antagonism in vitro, and intratumoral dendritic cells show higher expression of MHC class II in tumors from cIAP1/2 antagonism-treated mice. In this study, we use in vivo mouse models of syngeneic pancreatic cancer that generate endogenous T cell responses ranging from moderate to poor. Across multiple models, cIAP1/2 antagonism has pleiotropic beneficial effects on antitumor immunity, including direct effects on tumor-specific T cells leading to overall increased activation, increased control of tumor growth in vivo, synergy with multiple immunotherapy modalities, and immunologic memory. In contrast to checkpoint blockade, cIAP1/2 antagonism does not increase intratumoral T cell frequencies. Furthermore, we confirm our previous findings that even poorly immunogenic tumors with a paucity of T cells can experience T cell-dependent antitumor immunity, and we provide transcriptional clues into how these rare T cells coordinate downstream immune responses.


Asunto(s)
FN-kappa B , Neoplasias Pancreáticas , Ratones , Animales , FN-kappa B/metabolismo , Línea Celular Tumoral , Linfocitos T/metabolismo , Proteínas Inhibidoras de la Apoptosis , Apoptosis , Inmunidad
3.
Nature ; 565(7738): 186-191, 2019 01.
Artículo en Inglés | MEDLINE | ID: mdl-30626941

RESUMEN

We describe a de novo computational approach for designing proteins that recapitulate the binding sites of natural cytokines, but are otherwise unrelated in topology or amino acid sequence. We use this strategy to design mimics of the central immune cytokine interleukin-2 (IL-2) that bind to the IL-2 receptor ßγc heterodimer (IL-2Rßγc) but have no binding site for IL-2Rα (also called CD25) or IL-15Rα (also known as CD215). The designs are hyper-stable, bind human and mouse IL-2Rßγc with higher affinity than the natural cytokines, and elicit downstream cell signalling independently of IL-2Rα and IL-15Rα. Crystal structures of the optimized design neoleukin-2/15 (Neo-2/15), both alone and in complex with IL-2Rßγc, are very similar to the designed model. Neo-2/15 has superior therapeutic activity to IL-2 in mouse models of melanoma and colon cancer, with reduced toxicity and undetectable immunogenicity. Our strategy for building hyper-stable de novo mimetics could be applied generally to signalling proteins, enabling the creation of superior therapeutic candidates.


Asunto(s)
Diseño de Fármacos , Interleucina-15/inmunología , Interleucina-2/inmunología , Imitación Molecular , Receptores de Interleucina-2/agonistas , Receptores de Interleucina-2/inmunología , Secuencia de Aminoácidos , Animales , Sitios de Unión , Neoplasias del Colon/tratamiento farmacológico , Neoplasias del Colon/inmunología , Simulación por Computador , Cristalografía por Rayos X , Modelos Animales de Enfermedad , Humanos , Interleucina-15/uso terapéutico , Interleucina-2/uso terapéutico , Subunidad alfa del Receptor de Interleucina-2/inmunología , Subunidad alfa del Receptor de Interleucina-2/metabolismo , Melanoma/tratamiento farmacológico , Melanoma/inmunología , Ratones , Modelos Moleculares , Estabilidad Proteica , Receptores de Interleucina-2/metabolismo , Transducción de Señal/inmunología
4.
Artículo en Inglés | MEDLINE | ID: mdl-38650085

RESUMEN

Individuals with severe and treatment-resistant obsessive-compulsive disorder (trOCD) represent a small but severely disabled group of patients. Since trOCD cases eligible for deep brain stimulation (DBS) probably comprise the most severe end of the OCD spectrum, we hypothesize that they may be more likely to have a strong genetic contribution to their disorder. Therefore, while the worldwide population of DBS-treated cases may be small (~300), screening these individuals with modern genomic methods may accelerate gene discovery in OCD. As such, we have begun to collect DNA from trOCD cases who qualify for DBS, and here we report results from whole exome sequencing and microarray genotyping of our first five cases. All participants had previously received DBS in the bed nucleus of stria terminalis (BNST), with two patients responding to the surgery and one showing a partial response. Our analyses focused on gene-disruptive rare variants (GDRVs; rare, predicted-deleterious single-nucleotide variants or copy number variants overlapping protein-coding genes). Three of the five cases carried a GDRV, including a missense variant in the ion transporter domain of KCNB1, a deletion at 15q11.2, and a duplication at 15q26.1. The KCNB1 variant (hg19 chr20-47991077-C-T, NM_004975.3:c.1020G>A, p.Met340Ile) causes substitution of methionine for isoleucine in the trans-membrane region of neuronal potassium voltage-gated ion channel KV2.1. This KCNB1 substitution (Met340Ile) is located in a highly constrained region of the protein where other rare missense variants have previously been associated with neurodevelopmental disorders. The patient carrying the Met340Ile variant responded to DBS, which suggests that genetic factors could potentially be predictors of treatment response in DBS for OCD. In sum, we have established a protocol for recruiting and genomically characterizing trOCD cases. Preliminary results suggest that this will be an informative strategy for finding risk genes in OCD.

5.
Hum Mutat ; 20232023.
Artículo en Inglés | MEDLINE | ID: mdl-38084291

RESUMEN

Germline pathogenic variants in DICER1 predispose individuals to develop a variety of benign and malignant tumors. Accurate variant curation and classification is essential for reliable diagnosis of DICER1-related tumor predisposition and identification of individuals who may benefit from surveillance. Since 2015, most labs have followed the American College of Medical Genetics and Genomics and the Association for Molecular Pathology (ACMG/AMP) sequence variant classification guidelines for DICER1 germline variant curation. However, these general guidelines lack gene-specific nuances and leave room for subjectivity. Consequently, a group of DICER1 experts joined ClinGen to form the DICER1 and miRNA-Processing Genes Variant Curation Expert Panel (VCEP), to create DICER1- specific ACMG/AMP guidelines for germline variant curation. The VCEP followed the FDA-approved ClinGen protocol for adapting and piloting these guidelines. A diverse set of 40 DICER1 variants were selected for piloting, including 14 known Pathogenic/Likely Pathogenic (P/LP) variants, 12 known Benign/Likely Benign (B/LB) variants, and 14 variants classified as variants of uncertain significance (VUS) or with conflicting interpretations in ClinVar. Clinically meaningful classifications (i.e., P, LP, LB, or B) were achieved for 82.5% (33/40) of the pilot variants, with 100% concordance among the known P/LP and known B/LB variants. Half of the VUS or conflicting variants were resolved with four variants classified as LB and three as LP. These results demonstrate that the DICER1-specific guidelines for germline variant curation effectively classify known pathogenic and benign variants while reducing the frequency of uncertain classifications. Individuals and labs curating DICER1 variants should consider adopting this classification framework to encourage consistency and improve objectivity.


Asunto(s)
Pruebas Genéticas , Neoplasias , Humanos , Pruebas Genéticas/métodos , Variación Genética , Genoma Humano , Genómica/métodos , Neoplasias/genética , Células Germinativas , Ribonucleasa III/genética , ARN Helicasas DEAD-box/genética
6.
EMBO J ; 38(14): e101260, 2019 07 15.
Artículo en Inglés | MEDLINE | ID: mdl-31304630

RESUMEN

Tissue-resident iNKT cells maintain tissue homeostasis and peripheral surveillance against pathogens; however, studying these cells is challenging due to their low abundance and poor recovery from tissues. We here show that iNKT transnuclear mice, generated by somatic cell nuclear transfer, have increased tissue resident iNKT cells. We examined expression of PLZF, T-bet, and RORγt, as well as cytokine/chemokine profiles, and found that both monoclonal and polyclonal iNKT cells differentiated into functional subsets that faithfully replicated those seen in wild-type mice. We detected iNKT cells from tissues in which they are rare, including adipose, lung, skin-draining lymph nodes, and a previously undescribed population in Peyer's patches (PP). PP-NKT cells produce the majority of the IL-4 in Peyer's patches and provide indirect help for B-cell class switching to IgG1 in both transnuclear and wild-type mice. Oral vaccination with α-galactosylceramide shows enhanced fecal IgG1 titers in iNKT cell-sufficient mice. Transcriptional profiling reveals a unique signature of PP-NKT cells, characterized by tissue residency. We thus define PP-NKT as potentially important for surveillance for mucosal pathogens.


Asunto(s)
Perfilación de la Expresión Génica/métodos , Cambio de Clase de Inmunoglobulina , Inmunoglobulina G/genética , Células T Asesinas Naturales/metabolismo , Ganglios Linfáticos Agregados/inmunología , Animales , Diferenciación Celular , Células Cultivadas , Femenino , Galactosilceramidas/administración & dosificación , Galactosilceramidas/inmunología , Interleucina-4/genética , Ratones , Células T Asesinas Naturales/citología , Miembro 3 del Grupo F de la Subfamilia 1 de Receptores Nucleares/genética , Técnicas de Transferencia Nuclear , Proteína de la Leucemia Promielocítica con Dedos de Zinc/genética , Proteínas de Dominio T Box/genética , Vacunación
7.
Am J Hum Genet ; 107(4): 596-611, 2020 10 01.
Artículo en Inglés | MEDLINE | ID: mdl-32853555

RESUMEN

Newborn screening (NBS) was established as a public health program in the 1960s and is crucial for facilitating detection of certain medical conditions in which early intervention can prevent serious, life-threatening health problems. Genomic sequencing can potentially expand the screening for rare hereditary disorders, but many questions surround its possible use for this purpose. We examined the use of exome sequencing (ES) for NBS in the North Carolina Newborn Exome Sequencing for Universal Screening (NC NEXUS) project, comparing the yield from ES used in a screening versus a diagnostic context. We enrolled healthy newborns and children with metabolic diseases or hearing loss (106 participants total). ES confirmed the participant's underlying diagnosis in 15 out of 17 (88%) children with metabolic disorders and in 5 out of 28 (∼18%) children with hearing loss. We discovered actionable findings in four participants that would not have been detected by standard NBS. A subset of parents was eligible to receive additional information for their child about childhood-onset conditions with low or no clinical actionability, clinically actionable adult-onset conditions, and carrier status for autosomal-recessive conditions. We found pathogenic variants associated with hereditary breast and/or ovarian cancer in two children, a likely pathogenic variant in the gene associated with Lowe syndrome in one child, and an average of 1.8 reportable variants per child for carrier results. These results highlight the benefits and limitations of using genomic sequencing for NBS and the challenges of using such technology in future precision medicine approaches.


Asunto(s)
Neoplasias de la Mama/diagnóstico , Pruebas Genéticas/estadística & datos numéricos , Pérdida Auditiva/diagnóstico , Enfermedades Metabólicas/diagnóstico , Síndrome Oculocerebrorrenal/diagnóstico , Neoplasias Ováricas/diagnóstico , Neoplasias de la Mama/genética , Preescolar , Femenino , Genoma Humano , Pérdida Auditiva/genética , Heterocigoto , Humanos , Lactante , Recién Nacido , Masculino , Enfermedades Metabólicas/genética , Tamizaje Neonatal , North Carolina , Síndrome Oculocerebrorrenal/genética , Neoplasias Ováricas/genética , Salud Pública/métodos , Secuenciación del Exoma
8.
Behav Sleep Med ; 21(1): 97-116, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-35014925

RESUMEN

OBJECTIVE/BACKGROUND: Beyond sleep duration, the regularity of sleep patterns (e.g., sleep consistency), including variability in sleep timing (e.g., bedtime, wake time) and duration, is a critical marker of sleep health. Sleep consistency is captured using a variety of methods within the literature (e.g., sleep intraindividual variability, social jetlag), but most of the research focuses on adolescents. METHODS: Drawing on a developmental perspective, this narrative review highlights how normative changes at the individual (e.g., biological, cognitive, and social) and contextual (e.g., home, school, sociocultural) levels may contribute to inconsistent sleep patterns across development. RESULTS AND CONCLUSIONS: This review emphasizes how inconsistent sleep may increase across pivotal transitions throughout development (e.g., elimination of naps, puberty, summertime, entering college). Finally, recommendations for measuring sleep consistency and areas to address in future research are discussed.


Asunto(s)
Instituciones Académicas , Sueño , Adolescente , Preescolar , Humanos , Adulto , Síndrome Jet Lag , Duración del Sueño , Universidades
9.
Hum Mutat ; 42(3): 223-236, 2021 03.
Artículo en Inglés | MEDLINE | ID: mdl-33300245

RESUMEN

Germline pathogenic variants in TP53 are associated with Li-Fraumeni syndrome, a cancer predisposition disorder inherited in an autosomal dominant pattern associated with a high risk of malignancy, including early-onset breast cancers, sarcomas, adrenocortical carcinomas, and brain tumors. Intense cancer surveillance for individuals with TP53 germline pathogenic variants is associated with reduced cancer-related mortality. Accurate and consistent classification of germline variants across clinical and research laboratories is important to ensure appropriate cancer surveillance recommendations. Here, we describe the work performed by the Clinical Genome Resource TP53 Variant Curation Expert Panel (ClinGen TP53 VCEP) focused on specifying the American College of Medical Genetics and Genomics and the Association for Molecular Pathology (ACMG/AMP) guidelines for germline variant classification to the TP53 gene. Specifications were developed for 20 ACMG/AMP criteria, while nine were deemed not applicable. The original strength level for the 10 criteria was also adjusted due to current evidence. Use of TP53-specific guidelines and sharing of clinical data among experts and clinical laboratories led to a decrease in variants of uncertain significance from 28% to 12% compared with the original guidelines. The ClinGen TP53 VCEP recommends the use of these TP53-specific ACMG/AMP guidelines as the standard strategy for TP53 germline variant classification.


Asunto(s)
Variación Genética , Síndrome de Li-Fraumeni , Proteína p53 Supresora de Tumor , Pruebas Genéticas , Células Germinativas , Humanos , Síndrome de Li-Fraumeni/diagnóstico , Síndrome de Li-Fraumeni/genética , Proteína p53 Supresora de Tumor/genética , Estados Unidos
10.
Int J Behav Nutr Phys Act ; 18(1): 94, 2021 07 12.
Artículo en Inglés | MEDLINE | ID: mdl-34247639

RESUMEN

OBJECTIVES AND BACKGROUND: Social demands of the school-year and summer environment may affect children's sleep patterns and circadian rhythms during these periods. The current study examined differences in children's sleep and circadian-related behaviors during the school-year and summer and explored the association between sleep and circadian parameters and change in body mass index (BMI) during these time periods. METHODS: This was a prospective observational study with 119 children ages 5 to 8 years with three sequential BMI assessments: early school-year (fall), late school-year (spring), and beginning of the following school-year in Houston, Texas, USA. Sleep midpoint, sleep duration, variability of sleep midpoint, physical activity, and light exposure were estimated using wrist-worn accelerometry during the school-year (fall) and summer. To examine the effect of sleep parameters, physical activity level, and light exposure on change in BMI, growth curve modeling was conducted controlling for age, race, sex, and chronotype. RESULTS: Children's sleep midpoint shifted later by an average of 1.5 h during summer compared to the school-year. After controlling for covariates, later sleep midpoints predicted larger increases in BMI during summer, (γ = .0004, p = .03), but not during the school-year. Sleep duration, sleep midpoint variability, physical activity levels, and sedentary behavior were not associated with change in BMI during the school-year or summer. Females tended to increase their BMI at a faster rate during summer compared to males, γ = .06, p = .049. Greater amounts of outdoor light exposure (γ = -.01, p = .02) predicted smaller increases in school-year BMI. CONCLUSIONS: Obesity prevention interventions may need to target different behaviors depending on whether children are in or out of school. Promotion of outdoor time during the school-year and earlier sleep times during the summer may be effective obesity prevention strategies during these respective times.


Asunto(s)
Instituciones Académicas , Sueño , Aumento de Peso , Índice de Masa Corporal , Niño , Preescolar , Femenino , Humanos , Masculino , Estaciones del Año , Conducta Sedentaria
11.
Proc Natl Acad Sci U S A ; 115(15): 3912-3917, 2018 04 10.
Artículo en Inglés | MEDLINE | ID: mdl-29581255

RESUMEN

Ipilimumab, a monoclonal antibody that recognizes cytotoxic T lymphocyte antigen (CTLA)-4, was the first approved "checkpoint"-blocking anticancer therapy. In mouse tumor models, the response to antibodies against CTLA-4 depends entirely on expression of the Fcγ receptor (FcγR), which may facilitate antibody-dependent cellular phagocytosis, but the contribution of simple CTLA-4 blockade remains unknown. To understand the role of CTLA-4 blockade in the complete absence of Fc-dependent functions, we developed H11, a high-affinity alpaca heavy chain-only antibody fragment (VHH) against CTLA-4. The VHH H11 lacks an Fc portion, binds monovalently to CTLA-4, and inhibits interactions between CTLA-4 and its ligand by occluding the ligand-binding motif on CTLA-4 as shown crystallographically. We used H11 to visualize CTLA-4 expression in vivo using whole-animal immuno-PET, finding that surface-accessible CTLA-4 is largely confined to the tumor microenvironment. Despite this, H11-mediated CTLA-4 blockade has minimal effects on antitumor responses. Installation of the murine IgG2a constant region on H11 dramatically enhances its antitumor response. Coadministration of the monovalent H11 VHH blocks the efficacy of a full-sized therapeutic antibody. We were thus able to demonstrate that CTLA-4-binding antibodies require an Fc domain for antitumor effect.


Asunto(s)
Antígeno CTLA-4/inmunología , Fragmentos Fc de Inmunoglobulinas/administración & dosificación , Fragmentos de Inmunoglobulinas/administración & dosificación , Neoplasias/terapia , Animales , Anticuerpos Monoclonales/administración & dosificación , Anticuerpos Monoclonales/química , Anticuerpos Monoclonales/inmunología , Antígeno CTLA-4/química , Línea Celular Tumoral , Modelos Animales de Enfermedad , Humanos , Fragmentos Fc de Inmunoglobulinas/química , Fragmentos Fc de Inmunoglobulinas/inmunología , Fragmentos de Inmunoglobulinas/química , Fragmentos de Inmunoglobulinas/inmunología , Inmunoglobulina G/administración & dosificación , Inmunoglobulina G/inmunología , Inmunoterapia , Ratones , Ratones Endogámicos C57BL , Neoplasias/inmunología , Dominios Proteicos
12.
Genet Med ; 21(7): 1497-1506, 2019 07.
Artículo en Inglés | MEDLINE | ID: mdl-30504931

RESUMEN

PURPOSE: Several genes on hereditary breast and ovarian cancer susceptibility test panels have not been systematically examined for strength of association with disease. We employed the Clinical Genome Resource (ClinGen) clinical validity framework to assess the strength of evidence between selected genes and breast or ovarian cancer. METHODS: Thirty-one genes offered on cancer panel testing were selected for evaluation. The strength of gene-disease relationship was systematically evaluated and a clinical validity classification of either Definitive, Strong, Moderate, Limited, Refuted, Disputed, or No Reported Evidence was assigned. RESULTS: Definitive clinical validity classifications were made for 10/31 and 10/32 gene-disease pairs for breast and ovarian cancer respectively. Two genes had a Moderate classification whereas, 6/31 and 6/32 genes had Limited classifications for breast and ovarian cancer respectively. Contradictory evidence resulted in Disputed or Refuted assertions for 9/31 genes for breast and 4/32 genes for ovarian cancer. No Reported Evidence of disease association was asserted for 5/31 genes for breast and 11/32 for ovarian cancer. CONCLUSION: Evaluation of gene-disease association using the ClinGen clinical validity framework revealed a wide range of classifications. This information should aid laboratories in tailoring appropriate gene panels and assist health-care providers in interpreting results from panel testing.


Asunto(s)
Neoplasias de la Mama/genética , Neoplasias Ováricas/genética , Femenino , Estudios de Asociación Genética , Predisposición Genética a la Enfermedad , Pruebas Genéticas , Humanos
13.
J Pediatr ; 209: 68-76, 2019 06.
Artículo en Inglés | MEDLINE | ID: mdl-30851990

RESUMEN

OBJECTIVE: To assess the performance of a standardized, age-based metric for scoring clinical actionability to evaluate conditions for inclusion in newborn screening and compare it with the results from other contemporary methods. STUDY DESIGN: The North Carolina Newborn Exome Sequencing for Universal Screening study developed an age-based, semiquantitative metric to assess the clinical actionability of gene-disease pairs and classify them with respect to age of onset or timing of interventions. This categorization was compared with the gold standard Recommended Uniform Screening Panel and other methods to evaluate gene-disease pairs for newborn genomic sequencing. RESULTS: We assessed 822 gene-disease pairs, enriched for pediatric onset of disease and suspected actionability. Of these, 466 were classified as having childhood onset and high actionability, analogous to conditions selected for the Recommended Uniform Screening Panel core panel. Another 245 were classified as having childhood onset and low to no actionability, 25 were classified as having adult onset and high actionability, 19 were classified as having adult onset and low to no actionability, and 67 were excluded due to controversial evidence and/or prenatal onset. CONCLUSIONS: This study describes a novel method to facilitate decisions about the potential use of genomic sequencing for newborn screening. These categories may assist parents and physicians in making informed decisions about the disclosure of results from voluntary genomic sequencing in children.


Asunto(s)
Mapeo Cromosómico/métodos , Enfermedades Genéticas Congénitas/diagnóstico , Pruebas Genéticas/métodos , Tamizaje Neonatal/métodos , Análisis de Secuencia de ADN/métodos , Toma de Decisiones Conjunta , Femenino , Enfermedades Genéticas Congénitas/epidemiología , Genoma Humano , Humanos , Recién Nacido , Masculino , North Carolina , Secuenciación del Exoma
14.
Int J Behav Nutr Phys Act ; 16(1): 25, 2019 03 07.
Artículo en Inglés | MEDLINE | ID: mdl-30845969

RESUMEN

Children gain weight at an accelerated rate during summer, contributing to increases in the prevalence of overweight and obesity in elementary-school children (i.e., approximately 5 to 11 years old in the US). Int J Behav Nutr Phys Act 14:100, 2017 explained these changes with the "Structured Days Hypothesis" suggesting that environmental changes in structure between the school year and the summer months result in behavioral changes that ultimately lead to accelerated weight gain. The present article explores an alternative explanation, the circadian clock, including the effects of circannual changes and social demands (i.e., social timing resulting from societal demands such as school or work schedules), and implications for seasonal patterns of weight gain. We provide a model for understanding the role circadian and circannual rhythms may play in the development of child obesity, a framework for examining the intersection of behavioral and biological causes of obesity, and encouragement for future research into bio-behavioral causes of obesity in children.


Asunto(s)
Peso Corporal/fisiología , Ritmo Circadiano/fisiología , Obesidad Infantil/epidemiología , Estudiantes/estadística & datos numéricos , Niño , Preescolar , Humanos , Estaciones del Año
15.
Behav Sleep Med ; 17(3): 291-301, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-28617043

RESUMEN

BACKGROUND: Eveningness is associated with greater depressive symptoms in the general population. Depression and type 2 diabetes (T2D) commonly coexist. We aimed to explore the association between morningness-eveningness and depressive symptoms in T2D patients in the United States and in Thailand. PARTICIPANTS: T2D patients (n = 182) from an endocrinology clinic in Chicago, Illinois, and six hospitals in Thailand (n = 251) were enrolled. METHODS: Diabetes history was collected. Depressive symptoms were assessed by the Center for Epidemiologic Studies Depression scale (CES-D). The Chicago cohort completed the Morningness-Eveningness Questionnaire (MEQ) and the Thai cohort completed the Composite Scale of Morningness (CSM). Sleep quality was assessed using the Pittsburg Sleep Quality Index (PSQI). RESULTS: The mean (SD) CES-D score was 13.7 (9.1) in Chicago and 11.9 (6.4) in Thailand. In Chicago participants, after adjusting for age, sex, ethnicity, hemoglobin A1c, insulin use, and PSQI score, greater eveningness (lower MEQ scores) was associated with higher CESD scores (B = -0.117, p = 0.048). In Thai participants, after adjusting for age, sex, and PSQI score, eveningness (lower CSM score) was associated with higher CES-D score (B = -0.147, p = 0.016). In both cohorts, however, eveningness was not independently associated with the likelihood of being in the at-risk range for clinical depression (CES-D ≥ 16). CONCLUSIONS: Eveningness is independently associated with greater depressive symptoms in T2D in two different ethnic cohorts. The results support the association between individual differences in circadian rhythms and psychological functioning in T2D.


Asunto(s)
Ritmo Circadiano/fisiología , Depresión/psicología , Diabetes Mellitus Tipo 2/psicología , Etnicidad/psicología , Estudios de Cohortes , Diabetes Mellitus Tipo 2/patología , Femenino , Humanos , Masculino , Persona de Mediana Edad
16.
J Sleep Res ; 27(5): e12678, 2018 10.
Artículo en Inglés | MEDLINE | ID: mdl-29516556

RESUMEN

Sleep timing shifts later during adolescence (second decade). This trend reverses at ~20 years and continues to shift earlier into adulthood. The current analysis examined the hypothesis that a longer free-running circadian period during late adolescence (14-17 years) compared with adulthood (30-45 years) accounts for sleep timing differences. Sex and ancestry were also examined because previous reports find that women and those with African-American ancestry have shorter free-running periods. Circadian period was measured using an ultradian dark-light protocol (2 hr dark/sleep, 2 hr dim room light [~20 lux]/wake) over 3.4 days. Dim light melatonin onsets were measured before and after the ultradian protocol, from which the circadian period was derived. In contrast to our hypothesis, we found that free-running circadian period was similar in adolescents and adults. African-American adults had shorter free-running circadian periods compared with adults of other ancestries. This ancestry difference was not seen in the adolescent group. Finally, we observed a non-significant trend for shorter free-running circadian periods in females compared with males. These data suggest that age-related changes in circadian period after late adolescence do not account for sleep timing differences. These data provide further support for ancestry-related differences in period, particularly in adults. Whether the large difference in circadian period between African-American and other ancestries emerges later in development should be explored.


Asunto(s)
Ritmo Circadiano/fisiología , Sueño/fisiología , Adolescente , Adulto , Femenino , Humanos , Masculino , Persona de Mediana Edad
17.
J Adolesc ; 67: 55-65, 2018 08.
Artículo en Inglés | MEDLINE | ID: mdl-29908393

RESUMEN

The maturation of sleep regulatory systems during adolescence in combination with psychosocial and societal pressures culminate in a "Perfect Storm" of short and ill-timed sleep and the associated consequences for many youngsters. This model, first described by Carskadon in 2011, guides our current thinking of adolescent sleep behavior. Since the original description, the field has moved forward with remarkable pace, and this review aims to summarize recent progress and describe how this new work informs our understanding of sleep regulation and sleep behavior during this developmental time frame.


Asunto(s)
Conducta del Adolescente/fisiología , Desarrollo del Adolescente/fisiología , Sueño/fisiología , Adolescente , Ritmo Circadiano/fisiología , Femenino , Homeostasis/fisiología , Humanos , Masculino
18.
J Sleep Res ; 26(5): 547-550, 2017 10.
Artículo en Inglés | MEDLINE | ID: mdl-28332253

RESUMEN

The endogenous, free-running circadian period (τ) determines the phase relationship that an organism assumes when entrained to the 24-h day. We found a shorter circadian period in African Americans compared to non-Hispanic European Americans (24.07 versus 24.33 h). We speculate that a short circadian period, closer to 24 h, was advantageous to humans living around the equator, but when humans migrated North out of Africa, where the photoperiod changes with seasons, natural selection favoured people with longer circadian periods. Recently, in evolutionary terms, immigrants came from Europe and Africa to America ('the New World'). The Europeans were descendents of people who had lived in Europe for thousands of years with changing photoperiods (and presumably longer periods), whereas Africans had ancestors who had always lived around the equator (with shorter periods). It may have been advantageous to have a longer circadian period while living in Europe early in the evolution of humans. In our modern world, however, it is better to have a shorter period, because it helps make our circadian rhythms earlier, which is adaptive in our early-bird-dominated society. European American women had a shorter circadian period than men (24.24 versus 24.41), but there was no sex difference in African Americans (24.07 for both men and women). We speculate that selection pressures in Europe made men develop a slightly longer period than women to help them track dawn which could be useful for hunters, but less important for women as gatherers.


Asunto(s)
Ritmo Circadiano/genética , Ritmo Circadiano/fisiología , Caracteres Sexuales , África/etnología , Negro o Afroamericano , Europa (Continente)/etnología , Femenino , Migración Humana , Humanos , Masculino , Fotoperiodo , Estaciones del Año , Factores de Tiempo , Población Blanca
19.
J Sleep Res ; 26(6): 764-772, 2017 12.
Artículo en Inglés | MEDLINE | ID: mdl-28548389

RESUMEN

The circadian system plays a role in regulating metabolism. Night-shift work, a form of circadian misalignment, is associated with increased type 2 diabetes risk. This study aimed to determine if night-shift workers with type 2 diabetes experience poorer glycaemic control than non-shift workers. Patients with type 2 diabetes (104 unemployed, 85 day workers and 60 night-shift workers) participated. Sleep duration, sleep quality, morningness-eveningness preference, depressive symptoms and dietary intake were assessed using standardized questionnaires. Haemoglobin A1c levels were measured. Night-shift workers had significantly higher haemoglobin A1c levels compared with others, while there were no differences between day workers and unemployed participants (median 7.86% versus 7.24% versus 7.09%, respectively). Additionally, night-shift workers were younger, had a higher body mass index, and consumed more daily calories than others. Among night-shift workers, there were no significant differences in haemoglobin A1c levels between those performing rotating versus non-rotating shifts (P = 0.856), or those with clockwise versus counterclockwise shift rotation (P = 0.833). After adjusting for age, body mass index, insulin use, sleep duration, morningness-eveningness preference and percentage of daily intake from carbohydrates, night-shift work, compared with day work, was associated with significantly higher haemoglobin A1c (B = 0.059, P = 0.044), while there were no differences between unemployed participants and day workers (B = 0.016, P = 0.572). In summary, night-shift work is associated with poorer glycaemic control in patients with type 2 diabetes.


Asunto(s)
Glucemia/metabolismo , Diabetes Mellitus Tipo 2/complicaciones , Diabetes Mellitus Tipo 2/fisiopatología , Hemoglobina Glucada/metabolismo , Horario de Trabajo por Turnos , Tolerancia al Trabajo Programado/fisiología , Adulto , Factores de Edad , Índice de Masa Corporal , Ritmo Circadiano/fisiología , Depresión/complicaciones , Diabetes Mellitus Tipo 2/metabolismo , Dieta , Ingestión de Energía , Femenino , Hemoglobina Glucada/análisis , Humanos , Masculino , Persona de Mediana Edad , Sueño/fisiología , Encuestas y Cuestionarios , Factores de Tiempo
20.
Appetite ; 79: 91-6, 2014 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-24751916

RESUMEN

Night eating is a complex behavior associated with disruptions in eating, sleep, and mood regulation. While night eating has been associated with alterations in neuroendocrine functioning, night eating and Night Eating Syndrome (NES) are not well understood in patients with prevalent metabolic conditions, such as diabetes. In this study, 194 adults with Type 2 diabetes completed questionnaires assessing night eating symptoms as well as eating, sleep, and depressive symptoms. Glycemic control data, as measured by hemoglobin A1c (HbA1c), were gathered from patient medical charts. Results indicated that 7% of participants met criteria for NES. Increased symptoms of night eating were associated with poorer glycemic control and disruptions in eating, sleep, and mood, including significantly increased likelihood of having HbA1c levels >7% and endorsing clinical levels of depressive symptoms. Increasing understanding of the relationship between night eating and metabolic and psychosocial functioning in patients with diabetes may provide new avenues for treatment of these patients.


Asunto(s)
Afecto , Glucemia/metabolismo , Depresión/etiología , Diabetes Mellitus Tipo 2/complicaciones , Conducta Alimentaria , Trastornos de Alimentación y de la Ingestión de Alimentos/complicaciones , Sueño/fisiología , Anciano , Ritmo Circadiano , Trastorno Depresivo/etiología , Diabetes Mellitus Tipo 2/sangre , Diabetes Mellitus Tipo 2/psicología , Ingestión de Alimentos , Conducta Alimentaria/fisiología , Trastornos de Alimentación y de la Ingestión de Alimentos/epidemiología , Trastornos de Alimentación y de la Ingestión de Alimentos/psicología , Femenino , Intolerancia a la Glucosa/sangre , Intolerancia a la Glucosa/etiología , Hemoglobina Glucada/metabolismo , Humanos , Masculino , Persona de Mediana Edad , Prevalencia , Trastornos del Sueño-Vigilia/etiología , Encuestas y Cuestionarios , Síndrome
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