RESUMEN
Progressive decline of the adaptive immune system with increasing age coincides with a sharp increase in cancer incidence. In this study, we set out to understand whether deficits in antitumor immunity with advanced age promote tumor progression and/or drive resistance to immunotherapy. We found that multiple syngeneic cancers grew more rapidly in aged versus young adult mice, driven by dysfunctional CD8+ T-cell responses. By systematically mapping immune cell profiles within tumors, we identified loss of tumor antigen-specific CD8+ T cells as a primary feature accelerating the growth of tumors in aged mice and driving resistance to immunotherapy. When antigen-specific T cells from young adult mice were administered to aged mice, tumor outgrowth was delayed and the aged animals became sensitive to PD-1 blockade. These studies reveal how age-associated CD8+ T-cell dysfunction may license tumorigenesis in elderly patients and have important implications for the use of aged mice as pre-clinical models of aging and cancer.
RESUMEN
At homeostasis, a substantial proportion of Foxp3+ T regulatory cells (Tregs) have an activated phenotype associated with enhanced TCR signals and these effector Treg cells (eTregs) co-express elevated levels of PD-1 and CTLA-4. Short term in vivo blockade of the PD-1 or CTLA-4 pathways results in increased eTreg populations, while combination blockade of both pathways had an additive effect. Mechanistically, combination blockade resulted in a reduction of suppressive phospho-SHP2 Y580 in eTreg cells which was associated with increased proliferation, enhanced production of IL-10, and reduced dendritic cell and macrophage expression of CD80 and MHC-II. Thus, at homeostasis, PD-1 and CTLA-4 function additively to regulate eTreg function and the ability to target these pathways in Treg cells may be useful to modulate inflammation.
Asunto(s)
Receptor de Muerte Celular Programada 1 , Linfocitos T Reguladores , Linfocitos T Reguladores/metabolismo , Antígeno CTLA-4/genética , Receptor de Muerte Celular Programada 1/metabolismo , Antígeno B7-1/metabolismo , HomeostasisRESUMEN
Dispositional capacity assessment, which evaluates a patient's ability for self-care after hospital discharge, is a novel concept with important implications for work in consultation-liaison, inpatient, and emergency psychiatric settings. In this Open Forum, the authors present an illustrative case, review literature relevant to dispositional capacity, and explore social theory that elucidates the concept. Psychiatrists are specifically positioned to provide leadership in this area. Psychiatrists should consider further developing and formalizing criteria for dispositional capacity assessment.
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Liderazgo , Psiquiatría , Humanos , Pacientes Internos , Alta del Paciente , Derivación y ConsultaRESUMEN
PURPOSE OF REVIEW: Autism spectrum disorder (ASD) is a neurodevelopmental disorder characterized by core deficits in social communication and restricted, repetitive patterns of behavior. This article aims to review the recent literature pertaining to psychopharmacology for the core and associated symptoms of ASD including social impairment, repetitive behaviors, irritability, and language impairment. RECENT FINDINGS: Recent medication trials targeting social impairment in ASD have focused on neuropeptides (oxytocin and vasopressin) and memantine. None of these three medications has demonstrated consistent benefit for social impairment in ASD; however, additional studies are underway. Two double-blind, placebo-controlled studies on selective serotonin reuptake inhibitors (SSRIs) provide evidence against the use of SSRIs for repetitive behaviors in youth with ASD. Preliminary studies have investigated cannabidiol (CBD) for irritability in ASD but further studies are needed to demonstrate safety and efficacy. Finally, three double-blind, placebo-controlled studies provide preliminary evidence for folinic acid for the treatment of verbal language deficits in children with ASD. The identification of safe and effective pharmacological treatments to ameliorate the core and associated symptoms of ASD has proven difficult.
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Trastorno del Espectro Autista , Psicofarmacología , Adolescente , Trastorno del Espectro Autista/tratamiento farmacológico , Niño , Comunicación , Humanos , Genio Irritable , Ensayos Clínicos Controlados Aleatorios como Asunto , Inhibidores Selectivos de la Recaptación de SerotoninaRESUMEN
BACKGROUND: Despite the growing number of patients with limited English proficiency in the United States, not all medical schools offer medical language courses to train future physicians in practicing language-concordant care. Little is known about the long-term use of non-English languages among physicians who took language courses in medical school. We conducted a cross-sectional study to characterize the professional language use of Harvard Medical School (HMS) alumni who took a medical language course at HMS and identify opportunities to improve the HMS Medical Language Program. METHODS: Between October and November 2019, we sent an electronic survey to 803 HMS alumni who took a medical language course at HMS between 1991 and 2019 and collected responses. The survey had questions about the language courses and language use in the professional setting. We analyzed the data using descriptive statistics and McNemar's test for comparing proportions with paired data. The study was determined not to constitute human subjects research. RESULTS: The response rate was 26% (206/803). More than half of respondents (n = 118, 57%) cited their desire to use the language in their future careers as the motivation for taking the language courses. Twenty-eight (14%) respondents indicated a change from not proficient before taking the course to proficient at the time of survey whereas only one (0.5%) respondent changed from proficient to not proficient (McNemar's p-value < 0.0001). Respondents (n = 113, 56%) reported that clinical electives abroad influenced their cultural understanding of the local in-country population and their language proficiency. Only 13% (n = 27) of respondents have worked in a setting that required formal assessments of non-English language proficiency. CONCLUSIONS: HMS alumni of the Medical Language Program reported improved language proficiency after the medical language courses' conclusion, suggesting that the courses may catalyze long-term language learning. We found that a majority of respondents reported that the medical language courses influenced their desire to work with individuals who spoke the language of the courses they took. Medical language courses may equip physicians to practice language-concordant care in their careers.
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Médicos , Facultades de Medicina , Comprensión , Estudios Transversales , Humanos , Lenguaje , Estados UnidosRESUMEN
Currently, there is a pandemic forcing social distancing and, consequently, traditional in-person education must shift to a virtual curriculum to protect all parties and continue professional development. Recognizing that not all emergency medicine (EM) content can be taught through a virtual platform, we propose a model for nearly all EM resident didactic conference adaptation to a virtual format to meet the needs of the adult learner while protecting all participants from the current coronavirus pandemic.
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The objectives of this study were to characterize the sleep habits of 50 clinically referred individuals with Angelman syndrome (AS) and to retrospectively compare the effectiveness/tolerability of the three most commonly prescribed sleep medications in the sample. An experienced physician assigned a Clinical Global Impressions-Severity scale (CGI-S) score for each subject's AS-specific symptoms. Caregivers completed the Child Sleep Habits Questionnaire (CSHQ; screen for sleep problems in school-aged [4-10 years] children), a screening assessment for sleep problems. Caregivers provided information about medication trials targeting disturbed sleep, with the physician assigning a CGI-Improvement scale (CGI-I) score for each trial. Linear regression showed significant negative association between age and CSHQ score. In their lifetime, 72% of participants had taken a medication for sleep, most commonly melatonin, clonidine and trazodone. The majority continued these for 6 months or longer. With these medications, many demonstrated significant improvement in sleep disturbances, with no difference in odds of improvement between medications. Disturbed sleep was common in this cohort and significantly worse in younger-aged participants. The majority received at least one medication trial for disturbed sleep and each of the most commonly prescribed medication was effective for a substantial percentage of participants. Most participants remained on medication for at least 6 months, suggesting favorable tolerability.
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Síndrome de Angelman/tratamiento farmacológico , Trastornos del Sueño-Vigilia/tratamiento farmacológico , Sueño/efectos de los fármacos , Adolescente , Adulto , Síndrome de Angelman/complicaciones , Síndrome de Angelman/genética , Síndrome de Angelman/patología , Niño , Preescolar , Clonidina/administración & dosificación , Femenino , Humanos , Masculino , Melatonina/administración & dosificación , Sueño/fisiología , Trastornos del Sueño-Vigilia/complicaciones , Trastornos del Sueño-Vigilia/patología , Encuestas y Cuestionarios , Trazodona/administración & dosificación , Adulto JovenRESUMEN
BACKGROUND: The frequently cited Early Overgrowth Hypothesis of autism spectrum disorder (ASD) postulates that there is overgrowth of the brain in the first 2 years of life, which is followed by a period of arrested growth leading to normalized brain volume in late childhood and beyond. While there is consistent evidence for early brain overgrowth, there is mixed evidence for normalization of brain volume by middle childhood. The outcome of this debate is important to understanding the etiology and neurodevelopmental trajectories of ASD. METHODS: Brain volume was examined in two very large single-site samples of children, adolescents, and adults. The primary sample comprised 456 6-25-year-olds (ASD n = 240, typically developing controls (TDC) n = 216), including a large number of females (n = 102) and spanning a wide IQ range (47-158). The replication sample included 175 males. High-resolution T1-weighted anatomical MRI images were examined for group differences in total brain, cerebellar, ventricular, gray, and white matter volumes. RESULTS: The ASD group had significantly larger total brain, cerebellar, gray matter, white matter, and lateral ventricular volumes in both samples, indicating that brain volume remains enlarged through young adulthood, rather than normalizing. There were no significant age or sex interactions with diagnosis in these measures. However, a significant diagnosis-by-IQ interaction was detected in the larger sample, such that increased brain volume was related to higher IQ in the TDCs, but not in the ASD group. Regions-of-significance analysis indicated that total brain volume was larger in ASD than TDC for individuals with IQ less than 115, providing a potential explanation for prior inconsistent brain size results. No relationships were found between brain volume and measures of autism symptom severity within the ASD group. LIMITATIONS: Our cross-sectional sample may not reflect individual changes over time in brain volume and cannot quantify potential changes in volume prior to age 6. CONCLUSIONS: These findings challenge the "normalization" prediction of the brain overgrowth hypothesis by demonstrating that brain enlargement persists across childhood into early adulthood. The findings raise questions about the clinical implications of brain enlargement, since we find that it neither confers cognitive benefits nor predicts increased symptom severity in ASD.
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Trastorno Autístico/patología , Encéfalo/crecimiento & desarrollo , Encéfalo/patología , Modelos Biológicos , Adolescente , Adulto , Trastorno Autístico/diagnóstico , Trastorno Autístico/diagnóstico por imagen , Encéfalo/diagnóstico por imagen , Niño , Escolaridad , Femenino , Sustancia Gris/diagnóstico por imagen , Sustancia Gris/patología , Humanos , Inteligencia , Imagen por Resonancia Magnética , Masculino , Tamaño de los Órganos , Padres , Grupos Raciales , Índice de Severidad de la Enfermedad , Sustancia Blanca/diagnóstico por imagen , Sustancia Blanca/patología , Adulto JovenRESUMEN
The influence of alphaVbeta3 integrin on MT1-MMP functionality was studied in human breast cancer cells of differing beta3 integrin status. Overexpression of beta3 integrin caused increased cell surface expression of alphaV integrin and increased cellular adhesion to extracellular matrix (ECM) substrates in BT-549, MDA-MB-231 and MCF-7 cells. beta3 integrin expression also enhanced the migration of breast cancer cells on ECM substrates and enhanced collagen gel contraction. In vivo, alphaVbeta3 cooperated with MT1-MMP to increase the growth of MCF-7 cells after orthotopic inoculation in immunocompromised mice, but had no influence on in vitro proliferation. Despite these stimulatory effects, overexpression of beta3 integrin suppressed the type I collagen (Col I) induced MMP-2 activation in all breast cancer cell lines analyzed. This was also evident in extracts from the MCF-7 tumors in vivo, where MMP-2 activation was stimulated by MT1-MMP transfection, but attenuated with beta3 integrin expression. Although our studies confirm important biological effects of alphaVbeta3 integrin on enhancing cell adhesion and migration, ECM remodeling and tumor growth, beta3 integrin caused reduced MMP-2 activation in response to Col I in vitro, which appears to be physiologically relevant, as it was also seen in tumor xenografts in vivo. The reduction of MMP-2 activation (and thus MT1-MMP activity) by alphaVbeta3 in response to Col I may be important in scenarios where cells which are activated for matrix degradation need to preserve some pericellular collagen, perhaps as a substrate for cell adhesion and migration, thus maintaining a balanced level of proteolysis required for efficient tumor growth.
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Neoplasias de la Mama/metabolismo , Colágeno Tipo I/metabolismo , Regulación Enzimológica de la Expresión Génica , Regulación Neoplásica de la Expresión Génica , Integrina alfaVbeta3/metabolismo , Metaloproteinasa 14 de la Matriz/metabolismo , Metaloproteinasa 2 de la Matriz/metabolismo , Animales , Neoplasias de la Mama/patología , Línea Celular Tumoral , Activación Enzimática , Matriz Extracelular/metabolismo , Humanos , Ratones , Ratones Endogámicos BALB C , Trasplante de NeoplasiasRESUMEN
Both the integrin and insulin-like growth factor binding protein (IGFBP) families independently play important roles in modulating tumor cell growth and progression. We present evidence for a specific cell surface localization and a bimolecular interaction between the alpha v beta 3 integrin and IGFBP-2. The interaction, which could be specifically perturbed using vitronectin and alpha v beta 3 blocking antibodies, was shown to modulate IGF-mediated cellular migration responses. Moreover, this interaction was observed in vivo and correlated with reduced tumor size of the human breast cancer cells, MCF-7 beta 3, which overexpressed the alpha v beta 3 integrin. Collectively, these results indicate that alpha v beta 3 and IGFBP-2 act cooperatively in a negative regulatory manner to reduce tumor growth and the migratory potential of breast cancer cells.