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1.
Cell ; 142(1): 52-64, 2010 Jul 09.
Artículo en Inglés | MEDLINE | ID: mdl-20603014

RESUMEN

Cancer is influenced by its microenvironment, yet broader, environmental effects also play a role but remain poorly defined. We report here that mice living in an enriched housing environment show reduced tumor growth and increased remission. We found this effect in melanoma and colon cancer models, and that it was not caused by physical activity alone. Serum from animals held in an enriched environment (EE) inhibited cancer proliferation in vitro and was markedly lower in leptin. Hypothalamic brain-derived neurotrophic factor (BDNF) was selectively upregulated by EE, and its genetic overexpression reduced tumor burden, whereas BDNF knockdown blocked the effect of EE. Mechanistically, we show that hypothalamic BDNF downregulated leptin production in adipocytes via sympathoneural beta-adrenergic signaling. These results suggest that genetic or environmental activation of this BDNF/leptin axis may have therapeutic significance for cancer.


Asunto(s)
Factor Neurotrófico Derivado del Encéfalo/metabolismo , Neoplasias del Colon/metabolismo , Hipotálamo/metabolismo , Leptina/metabolismo , Melanoma/metabolismo , Transducción de Señal , Medio Social , Adipocitos/metabolismo , Animales , Factor Neurotrófico Derivado del Encéfalo/genética , Neoplasias del Colon/genética , Neoplasias del Colon/fisiopatología , Genes APC , Vivienda para Animales , Hipotálamo/citología , Inmunocompetencia , Melanoma/genética , Melanoma/fisiopatología , Ratones , Ratones Endogámicos C57BL , Procesos Neoplásicos , Distribución Aleatoria , Receptores Adrenérgicos beta/metabolismo
2.
Telemed J E Health ; 28(9): 1261-1269, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-35049402

RESUMEN

Introduction: The COVID-19 pandemic accelerated the adoption of telehealth as an alternative to in-person hospital visits. To understand the factors impacting the quality of telehealth services, there is a need for validated survey instruments and conceptual frameworks. The objective of this study is to validate a telehealth patient satisfaction survey by structural equation modeling (SEM) and determine the relationship between the factors in the proposed telehealth patient satisfaction model (TPSM). Methods: We conducted a cross-sectional survey of pediatric patients and families receiving care from a comprehensive pediatric hospital in the Midwest between September 2020 and January 2021. In total, 2,039 usable responses were collected. We used an SEM approach by performing confirmatory factor analysis with Diagonally Weighted Least Squares modeling and Partial Least Squares-Path Modeling to establish the structural validity and examined the relationships among the constructs of "Admission Process" (AP), "Perceived Quality of Service" (PQS), and "Telehealth Satisfaction" (TS). Results: Participants were predominantly White (75%) and English-speaking (95%) parents (85%) of patients (mean age of patients was 10.2 years old). The survey responses were collected from patients visiting 43 department specialties, whereas 50% were behavioral and occupational therapy patients. The structural model showed that the admission process (AP) had a strong positive impact on perceived quality of service (PQS) (p = 0.67, t = 36.1, p < 0.001). The PQS had a strong positive impact on telehealth satisfaction (TS) (p = 0.66, t = 31.8, p < 0.001). The AP had a low positive direct impact on TS (p = 0.16, t = 7.46, p < 0.05). Overall, AP and PQS explained 61% variances (R2) of TS. Conclusions: We validated a newly proposed TS assessment model by using SEM. The TPSM will inform researchers to better understand the influencing factors in TS and help health care systems to improve telehealth patient satisfaction through a validated model.


Asunto(s)
COVID-19 , Telemedicina , COVID-19/epidemiología , Niño , Estudios Transversales , Humanos , Análisis de Clases Latentes , Pandemias , Satisfacción del Paciente
3.
Telemed J E Health ; 28(9): 1270-1279, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-35049390

RESUMEN

Introduction: The COVID-19 pandemic has hastened the adoption of telehealth and the drastic shift to an unfamiliar process may impose significant impact to the quality-of-care delivery. Many providers are interested in understanding the quality of their telehealth services from the patients' experience. Materials and Methods: A telehealth patient satisfaction survey (TPSS) was developed by using an iterative stakeholder-centered design approach, incorporating elements from validated telemedicine and customer service survey instruments, and meeting the operational needs and constraints. A cross-sectional study design was employed to collect survey responses from patients and families of a large pediatric hospital. Finally, we performed exploratory factor analysis (EFA) to extract latent constructs and factor loadings of the survey items to further explain relationships. Results: A 22-item TPSS closely matched the existing in-person patient satisfaction survey and mapped to a revised SERVPERF conceptual model that was proposed by the interdisciplinary committee. Survey was implemented in the HIPAA-compliant online platform REDCap® with survey link embedded in an automated Epic MyChart (Verona, WI) visit follow-up message. In total, 2,394 survey responses were collected between July 7, 2020, and September 2, 2020. EFA revealed three constructs (with factor loadings >0.30): admission process, perceived quality of services, and telehealth satisfaction. Conclusions: We reported the development of TPSS that met the operational needs of compatibility with existing data and possible comparison to in-person survey. The survey is short and yet covers both the clinical experience and telehealth usability, with acceptable survey validity.


Asunto(s)
COVID-19 , Telemedicina , COVID-19/epidemiología , Niño , Estudios Transversales , Humanos , Pandemias , Satisfacción del Paciente
4.
Nat Med ; 13(11): 1333-40, 2007 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-17982462

RESUMEN

Anorexia and weight loss are part of the wasting syndrome of late-stage cancer, are a major cause of morbidity and mortality in cancer, and are thought to be cytokine mediated. Macrophage inhibitory cytokine-1 (MIC-1) is produced by many cancers. Examination of sera from individuals with advanced prostate cancer showed a direct relationship between MIC-1 abundance and cancer-associated weight loss. In mice with xenografted prostate tumors, elevated MIC-1 levels were also associated with marked weight, fat and lean tissue loss that was mediated by decreased food intake and was reversed by administration of antibody to MIC-1. Additionally, normal mice given systemic MIC-1 and transgenic mice overexpressing MIC-1 showed hypophagia and reduced body weight. MIC-1 mediates its effects by central mechanisms that implicate the hypothalamic transforming growth factor-beta receptor II, extracellular signal-regulated kinases 1 and 2, signal transducer and activator of transcription-3, neuropeptide Y and pro-opiomelanocortin. Thus, MIC-1 is a newly defined central regulator of appetite and a potential target for the treatment of both cancer anorexia and weight loss, as well as of obesity.


Asunto(s)
Anorexia/metabolismo , Citocinas/fisiología , Familia de Multigenes/inmunología , Neoplasias de la Próstata/metabolismo , Pérdida de Peso , Animales , Anorexia/genética , Anorexia/inmunología , Anorexia/fisiopatología , Anticuerpos/administración & dosificación , Anticuerpos/fisiología , Línea Celular Tumoral , Citocinas/sangre , Citocinas/genética , Citocinas/inmunología , Factor 15 de Diferenciación de Crecimiento , Humanos , Masculino , Ratones , Ratones Endogámicos BALB C , Ratones Endogámicos C57BL , Ratones Desnudos , Ratones Transgénicos , Neoplasias de la Próstata/sangre , Neoplasias de la Próstata/inmunología , Neoplasias de la Próstata/fisiopatología , Factor de Crecimiento Transformador beta/genética , Factor de Crecimiento Transformador beta/inmunología , Factor de Crecimiento Transformador beta/fisiología , Pérdida de Peso/genética , Pérdida de Peso/inmunología
5.
Appl Clin Inform ; 13(1): 230-241, 2022 01.
Artículo en Inglés | MEDLINE | ID: mdl-35172372

RESUMEN

BACKGROUND: The rapid, large-scale deployment of new health technologies can introduce challenges to clinicians who are already under stress. The novel coronavirus disease 19 (COVID-19) pandemic transformed health care in the United States to include a telehealth model of care delivery. Clarifying paths through which telehealth technology use is associated with change in provider well-being and interest in sustaining virtual care delivery can inform planning and optimization efforts. OBJECTIVE: This study aimed to characterize provider-reported changes in well-being and daily work associated with the pandemic-accelerated expansion of telehealth and assess the relationship of provider perceptions of telehealth effectiveness, efficiency, and work-life balance with desire for future telehealth. METHODS: A cross-sectional survey study was conducted October through November 2020, 6 months after the outbreak of COVID-19 at three children's hospitals. Factor analysis and structural equation modeling (SEM) were used to examine telehealth factors associated with reported change in well-being and desire for future telehealth. RESULTS: A total of 947 nontrainee physicians, advanced practice providers, and psychologists were surveyed. Of them, 502 (53.0%) providers responded and 467 (49.3%) met inclusion criteria of telehealth use during the study period. Of these, 325 (69.6%) were female, 301 (65.6%) were physicians, and 220 (47.1%) were medical subspecialists. Providers were 4.77 times as likely (95% confidence interval [CI]: 3.29-7.06) to report improved versus worsened well-being associated with telehealth. Also, 95.5% of providers (95% CI: 93.2-97.2%) wish to continue performing telehealth postpandemic. Our model explains 66% of the variance in telehealth-attributed provider well-being and 59% of the variance for future telehealth preference and suggests telehealth resources significantly influence provider-perceived telehealth care effectiveness which in turn significantly influences provider well-being and desire to perform telehealth. CONCLUSION: Telehealth has potential to promote provider well-being; telehealth-related changes in provider well-being are associated with both provider-perceived effectiveness of telemedicine for patients and adequacy of telehealth resources.


Asunto(s)
COVID-19 , Telemedicina , Niño , Estudios Transversales , Femenino , Personal de Salud , Humanos , SARS-CoV-2 , Estados Unidos
6.
iScience ; 25(8): 104709, 2022 Aug 19.
Artículo en Inglés | MEDLINE | ID: mdl-35813875

RESUMEN

Post-translational modifications (PTMs), such as glycosylation and palmitoylation, are critical to protein folding, stability, intracellular trafficking, and function. Understanding regulation of PTMs of SARS-CoV-2 spike (S) protein could help the therapeutic drug design. Herein, the VSV vector was used to produce SARS-CoV-2 S pseudoviruses to examine the roles of the 611LYQD614 and cysteine-rich motifs in S protein maturation and virus infectivity. Our results show that 611LY612 mutation alters S protein intracellular trafficking and reduces cell surface expression level. It also changes S protein glycosylation pattern and decreases pseudovirus infectivity. The S protein contains four cysteine-rich clusters with clusters I and II as the main palmitoylation sites. Mutations of clusters I and II disrupt S protein trafficking from ER-to-Golgi, suppress pseudovirus production, and reduce spike-mediated membrane fusion activity. Taken together, glycosylation and palmitoylation orchestrate the S protein maturation processing and are critical for S protein-mediated membrane fusion and infection.

7.
Front Immunol ; 13: 872047, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35585971

RESUMEN

An effective COVID-19 vaccine against broad SARS-CoV-2 variants is still an unmet need. In the study, the vesicular stomatitis virus (VSV)-based vector was used to express the SARS-CoV-2 Spike protein to identify better vaccine designs. The replication-competent of the recombinant VSV-spike virus with C-terminal 19 amino acid truncation (SΔ19 Rep) was generated. A single dose of SΔ19 Rep intranasal vaccination is sufficient to induce protective immunity against SARS-CoV-2 infection in hamsters. All the clones isolated from the SΔ19 Rep virus contained R682G mutation located at the Furin cleavage site. An additional S813Y mutation close to the TMPRSS2 cleavage site was identified in some clones. The enzymatic processing of S protein was blocked by these mutations. The vaccination of the R682G-S813Y virus produced a high antibody response against S protein and a robust S protein-specific CD8+ T cell response. The vaccinated animals were protected from the lethal SARS-CoV-2 (delta variant) challenge. The S antigen with resistance to enzymatic processes by Furin and TMPRSS2 will provide better immunogenicity for vaccine design.


Asunto(s)
COVID-19 , Furina , SARS-CoV-2 , Serina Endopeptidasas , Animales , COVID-19/inmunología , COVID-19/prevención & control , COVID-19/virología , Vacunas contra la COVID-19 , Furina/genética , Furina/metabolismo , Humanos , Inmunidad Celular , SARS-CoV-2/inmunología , Serina Endopeptidasas/genética , Serina Endopeptidasas/inmunología , Glicoproteína de la Espiga del Coronavirus/inmunología
8.
J Dent Educ ; 85(6): 856-865, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-33638168

RESUMEN

PURPOSE: Social determinants of health (SDOH) significantly impact individuals' engagement with the healthcare system. To address SDOH-related oral health disparities, providers must be equipped with knowledge, skills, and attitudes (KSAs) to understand how SDOH affect patients and how to mitigate these effects. Traditional dental school curricula provide limited training on recognizing SDOH or developing empathy for those with SDOH-related access barriers. This study describes the design and evaluation of such a virtual reality (VR)-based simulation in dental training. We hypothesize the simulation will increase post-training KSAs. METHODS: We developed "MPATHI" (Making Professionals Able THrough Immersion), a scripted VR simulation where participants take the role of an English-speaking caregiver with limited socioeconomic resources seeking dental care for a child in a Spanish-speaking country. The simulation is a combination of 360° video recording and virtual scenes delivered via VR headsets. A pilot was conducted with 29 dental residents/faculty, utilizing a pre-post design to evaluate effectiveness in improving immediate and retention of KSAs toward care delivery for families facing barriers. RESULTS: MPATHI led to increased mean scores for cognitive (pre = 3.48 ± 0.80, post = 4.56 ± 0.51, p < 0.001), affective (pre = 4.20 ± 0.4, post = 4.47 ± 0.44, p < 0.001), and skill-based learning (pre = 4.00 ± 0.47, post = 4.52 ± 0.37, p < 0.001) immediately post-training. There was not a significant difference between skills measured immediately post-training and in the 1-month post-training survey (p = 0.41). Participants reported high satisfaction with the content and methods used in this training. CONCLUSIONS: This pilot study supports using VR SDOH training in dental education. VR technology provides new opportunities for innovative content design.


Asunto(s)
Entrenamiento Simulado , Realidad Virtual , Niño , Competencia Clínica , Empatía , Estudios de Factibilidad , Humanos , Proyectos Piloto
9.
JMIR Serious Games ; 8(3): e16947, 2020 Aug 25.
Artículo en Inglés | MEDLINE | ID: mdl-32447275

RESUMEN

BACKGROUND: Traumatic brain injury (TBI) poses a significant threat to children's health. Cognitive rehabilitation for pediatric TBI has the potential to improve the quality of life following the injury. Virtual reality (VR) can provide enriched cognitive training in a life-like but safe environment. However, existing VR applications for pediatric TBIs have primarily focused on physical rehabilitation. OBJECTIVE: This study aims to design and develop an integrative hardware and software VR system to provide rehabilitation of executive functions (EF) for children with TBI, particularly in 3 core EF: inhibitory control, working memory, and cognitive flexibility. METHODS: The VR training system was developed by an interdisciplinary team with expertise in best practices of VR design, developmental psychology, and pediatric TBI rehabilitation. Pilot usability testing of this novel system was conducted among 10 healthy children and 4 children with TBIs. RESULTS: Our VR-based interactive cognitive training system was developed to provide assistive training on core EF following pediatric TBI. Pilot usability testing showed adequate user satisfaction ratings for both the hardware and software components of the VR system. CONCLUSIONS: This project designed and tested a novel VR-based system for executive function rehabilitation that is specifically adapted to children following TBI.

10.
Mol Cell Neurosci ; 39(2): 229-37, 2008 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-18652899

RESUMEN

Neuropeptide Y (NPY) gene transduction of the brain using viral vectors in epileptogenic regions can effectively suppress seizures in animals, and is being considered as a promising alternative treatment strategy for epilepsy. Therefore, it is fundamental to understand the detailed mechanisms governing the release and action of transgene NPY in neuronal circuitries. Using whole-cell recordings from subicular neurons, we show that in animals transduced by recombinant adeno-associated viral (rAAV) vector carrying the NPY gene, transgene NPY is released during high-frequency activation of CA1-subicular synapses. Released transgene NPY attenuates excitatory synaptic transmission not only in activated, but also in neighboring, non-activated synapses. Such broad action of transgene NPY may prevent recruitment of excitatory synapses in epileptic activity and could play a key role in limiting the spread and generalization of seizures.


Asunto(s)
Ácido Glutámico/metabolismo , Hipocampo/fisiología , Potenciación a Largo Plazo/genética , Neuropéptido Y/genética , Transgenes/fisiología , Animales , Animales Recién Nacidos , Arginina/análogos & derivados , Arginina/farmacología , Benzazepinas/farmacología , Fenómenos Biofísicos , Distribución de Chi-Cuadrado , Estimulación Eléctrica/métodos , Potenciales Postsinápticos Excitadores/fisiología , Femenino , Antagonistas del GABA/farmacología , Vectores Genéticos/genética , Proteínas Fluorescentes Verdes/genética , Hipocampo/citología , Técnicas In Vitro , Potenciación a Largo Plazo/fisiología , Masculino , Neuronas/fisiología , Neuropéptido Y/metabolismo , Técnicas de Placa-Clamp/métodos , Fosfopiruvato Hidratasa/genética , Fosfopiruvato Hidratasa/metabolismo , Picrotoxina/farmacología , Ratas , Ratas Sprague-Dawley , Receptores de Neuropéptido Y/antagonistas & inhibidores , Tetrodotoxina/farmacología
11.
Am J Manag Care ; 25(10): e310-e315, 2019 10 01.
Artículo en Inglés | MEDLINE | ID: mdl-31622071

RESUMEN

OBJECTIVES: Current models for patient risk prediction rely on practitioner expertise and domain knowledge. This study presents a deep learning model-a type of machine learning that does not require human inputs-to analyze complex clinical and financial data for population risk stratification. STUDY DESIGN: A comparative predictive analysis of deep learning versus other popular risk prediction modeling strategies using medical claims data from a cohort of 112,641 pediatric accountable care organization members. METHODS: "Skip-Gram," an unsupervised deep learning approach that uses neural networks for prediction modeling, used data from 2014 and 2015 to predict the risk of hospitalization in 2016. The area under the curve (AUC) of the deep learning model was compared with that of both the Clinical Classifications Software and the commercial DxCG Intelligence predictive risk models, each with and without demographic and utilization features. We then calculated costs for patients in the top 1% and 5% of hospitalization risk identified by each model. RESULTS: The deep learning model performed the best across 6 predictive models, with an AUC of 75.1%. The top 1% of members selected by the deep learning model had a combined healthcare cost $5 million higher than that of the group identified by the DxCG Intelligence model. CONCLUSIONS: The deep learning model outperforms the traditional risk models in prospective hospitalization prediction. Thus, deep learning may improve the ability of managed care organizations to perform predictive modeling of financial risk, in addition to improving the accuracy of risk stratification for population health management activities.


Asunto(s)
Organizaciones Responsables por la Atención/estadística & datos numéricos , Aprendizaje Profundo , Servicios de Salud/estadística & datos numéricos , Factores de Edad , Niño , Recursos en Salud , Humanos , Redes Neurales de la Computación , Estudios Prospectivos , Reproducibilidad de los Resultados , Características de la Residencia , Medición de Riesgo , Factores de Riesgo , Factores Sexuales , Factores Socioeconómicos
12.
Mol Endocrinol ; 21(7): 1722-35, 2007 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-17456788

RESUMEN

Endogenous opioids, particularly dynorphins, have been implicated in regulation of energy balance, but it is not known how they mediate this in vivo. We investigated energy homeostasis in dynorphin knockout mice (Dyn(-/-) mice) and probed the interactions between dynorphins and the neuropeptide Y (NPY) system. Dyn(-/-) mice were no different from wild types with regards to body weight and basal and fasting-induced food intake, but fecal output was increased, suggesting decreased nutrient absorption, and they had significantly less white fat and lost more weight during a 24-h fast. The neuroendocrine and thermal responses to fasting were at least as pronounced in Dyn(-/-) as in wild types, and there was no stimulatory effect of dynorphin knockout on 24-h energy expenditure (kilocalories of heat produced) or physical activity. However, Dyn(-/-) mice showed increased circulating concentrations of 3,4-dihydroxyphenlacetic acid and 3,4-dihydroxyphenylglycol, suggesting increased activity of the sympathetic nervous system. The respiratory exchange ratio of male but not female Dyn(-/-) mice was reduced, demonstrating increased fat oxidation. Interestingly, expression of the orexigenic acting NPY in the hypothalamic arcuate nucleus was reduced in Dyn(-/-) mice. However, fasting-induced increases in pre-prodynorphin expression in the arcuate nucleus, the paraventricular nucleus, and the ventromedial hypothalamus but not the lateral hypothalamus were abolished by deletion of Y(1) but not Y(2) receptors. Therefore, ablation of dynorphins results in increases in fatty acid oxidation in male mice, reductions in adiposity, and increased weight loss during fasting, possibly via increases in sympathetic activity, decreases in intestinal nutrient absorption, and interactions with the NPYergic system.


Asunto(s)
Dinorfinas/deficiencia , Dinorfinas/genética , Pérdida de Peso/fisiología , Tejido Adiposo/patología , Animales , Peso Corporal/fisiología , Dinorfinas/fisiología , Ingestión de Alimentos/fisiología , Metabolismo Energético , Ayuno/metabolismo , Femenino , Glucosa/metabolismo , Homeostasis , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Neuropéptido Y/genética , Sistemas Neurosecretores/fisiología , Esfuerzo Físico , ARN Mensajero/genética , ARN Mensajero/metabolismo
13.
J Glaucoma ; 17(2): 105-10, 2008 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-18344755

RESUMEN

PURPOSE: To study the retinal nerve fiber layer thickness difference between high-tension primary open angle glaucoma (HT-POAG) and primary angle closure glaucoma (PACG) eyes using scanning laser polarimetry-variable corneal compensation (GDx VCC) in Taiwan-Chinese population; to evaluate the usefulness of the GDx VCC for detecting POAG and PACG eyes in Taiwan-Chinese population. PATIENTS AND METHODS: The study comprised 88 early to moderate glaucomatous eyes (one randomly selected eye from 47 HT-POAG patients and 41 PACG patients) and the control group consisted of 45 age-matched eyes from 45 normal individuals. Each subject underwent retinal nerve fiber layer thickness measurement by GDx VCC and Humphrey Field Analyzer visual field testing. Measured GDx VCC parameters were compared among groups. We also calculated the area under the receive operator characteristic (AROC) curve, corresponding sensitivity/specificity and best cut off value for each parameter in differentiating normal from POAG and PACG eyes. RESULTS: There was no significant difference between HT-POAG and PACG eyes in each parameter. The parameter with the best AROC curve for differentiating normal from POAG eye was nerve fiber indicator (AROC, 0.779; sensitivity=57.4%, specificity=100%; best cut off value >27). The parameter with the best AROC curves for differentiating normal from PACG eyes was temporal-superior-nasal-inferior-temporal average (AROC, 0.829; sensitivity=46.3%, specificity=100%, best cut off value <51.7). CONCLUSIONS: There was no significant difference between the HT-POAG and PACG eyes as far as the various parameters were concerned. GDx VCC shows fair discriminating ability in distinguishing normal from POAG and PACG eyes in Taiwan Chinese population.


Asunto(s)
Técnicas de Diagnóstico Oftalmológico , Glaucoma de Ángulo Cerrado/diagnóstico , Glaucoma de Ángulo Abierto/diagnóstico , Fibras Nerviosas/patología , Enfermedades del Nervio Óptico/diagnóstico , Células Ganglionares de la Retina/patología , Área Bajo la Curva , Birrefringencia , Córnea/fisiología , Estudios Transversales , Humanos , Presión Intraocular , Rayos Láser , Persona de Mediana Edad , Estudios Prospectivos , Curva ROC , Sensibilidad y Especificidad , Pruebas del Campo Visual/métodos , Campos Visuales
14.
Endocrinology ; 148(5): 2056-65, 2007 May.
Artículo en Inglés | MEDLINE | ID: mdl-17272395

RESUMEN

Neuropeptide Y, a neuropeptide abundantly expressed in the brain, has been implicated in the regulation of the hypothalamo-pituitary-somatotropic axis and the hypothalamo-pituitary-gonadotropic axis. Elevated hypothalamic neuropeptide Y expression, such as that occurs during fasting, is known to inhibit both of these axes. However, it is not known which Y receptor(s) mediate these effects. Here we demonstrate, using Y receptor knockout mice, that Y2 and Y4 receptors are separately involved in the regulation of these axes. Fasting-induced inhibition of hypothalamic GHRH mRNA expression and reduction of circulating IGF-I levels were observed in wild-type and Y4(-/-) mice but not Y2(-/-) or Y2(-/-)Y4(-/-) mice. In contrast, fasting-induced reduction of GnRH expression in the medial preoptic area and testis testosterone content were abolished in the absence of Y4 receptors. Colocalization of Y2 receptors and GHRH in the arcuate nucleus (Arc) suggests that GHRH mRNA expression in this region might be directly regulated by Y2 receptors. Indeed, hypothalamic-specific deletion of Y2 receptors in conditional knockout mice prevented the fasting-induced reduction in Arc GHRH mRNA expression. On the other hand, fasting-induced decrease in GnRH mRNA expression in the medial preoptic area is more likely indirectly influenced by Y4 receptors because no Y4 receptors could be detected on GnRH neurons in this region. Together these data show that fasting inhibits the somatotropic axis via direct action on Y2 receptors in the Arc and indirectly inhibits the gonadotropic axis via Y4 receptors.


Asunto(s)
Ayuno/fisiología , Sistema Hipotálamo-Hipofisario/crecimiento & desarrollo , Sistema Hipotálamo-Hipofisario/fisiología , Receptores de Neuropéptido Y/metabolismo , Reproducción/fisiología , Animales , Núcleo Arqueado del Hipotálamo/crecimiento & desarrollo , Núcleo Arqueado del Hipotálamo/fisiología , Gónadas/crecimiento & desarrollo , Gónadas/fisiología , Hormona del Crecimiento/metabolismo , Células Intersticiales del Testículo/metabolismo , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Hipófisis/crecimiento & desarrollo , Hipófisis/fisiología , Área Preóptica/crecimiento & desarrollo , Área Preóptica/fisiología , ARN Mensajero/metabolismo , Receptores de Neuropéptido/genética , Receptores de Neuropéptido Y/genética , Receptores de Hormona Reguladora de Hormona Hipofisaria/genética , Testículo/citología , Testículo/crecimiento & desarrollo , Testículo/fisiología , Testosterona/metabolismo
15.
Endocrinology ; 147(11): 5094-101, 2006 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-16873543

RESUMEN

Neuropeptide Y (NPY) is a key regulator of energy homeostasis and is implicated in the development of obesity and type 2 diabetes. Whereas it is known that hypothalamic administration of exogenous NPY peptides leads to increased body weight gain, hyperphagia, and many hormonal and metabolic changes characteristic of an obesity syndrome, the Y receptor(s) mediating these effects is disputed and unclear. To investigate the role of different Y receptors in the NPY-induced obesity syndrome, we used recombinant adeno-associated viral vector to overexpress NPY in mice deficient of selective single or multiple Y receptors (including Y1, Y2, and Y4). Results from this study demonstrated that long-term hypothalamic overexpression of NPY lead to marked hyperphagia, hypogonadism, body weight gain, enhanced adipose tissue accumulation, hyperinsulinemia, and other hormonal changes characteristic of an obesity syndrome. NPY-induced hyperphagia, hypogonadism, and obesity syndrome persisted in all genotypes studied (Y1(-/-), Y2(-/-), Y2Y4(-/-), and Y1Y2Y4(-/-) mice). However, triple deletion of Y1, Y2, and Y4 receptors prevented NPY-induced hyperinsulinemia. These findings suggest that Y1, Y2, and Y4 receptors under this condition are not crucially involved in NPY's hyperphagic, hypogonadal, and obesogenic effects, but they are responsible for the central regulation of circulating insulin levels by NPY.


Asunto(s)
Hiperinsulinismo/prevención & control , Hiperfagia/etiología , Hipotálamo/fisiología , Neuropéptido Y/fisiología , Obesidad/etiología , Receptores de Neuropéptido Y/fisiología , Tejido Adiposo/metabolismo , Animales , Glucemia/análisis , Peso Corporal , Femenino , Humanos , Hiperinsulinismo/etiología , Hiperfagia/sangre , Ratones , Ratones Endogámicos C57BL , Obesidad/sangre
16.
Neuropharmacology ; 51(7-8): 1129-36, 2006 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-16919686

RESUMEN

Antipsychotic drugs have been used effectively for the treatment of schizophrenia symptoms, but they are often associated with metabolic side effects such as weight gain and endocrine disruptions. To investigate the possible mechanisms of antipsychotic-induced metabolic effects, we studied the impact of chronic administration of a typical antipsychotic drug (haloperidol) and an atypical antipsychotic (risperidone) to male rats on food intake, body weight, adiposity, and the circulating concentrations of hormones and metabolites that can influence energy homeostasis. Chronic (28days) haloperidol administration had no effect on food intake, weight gain or adiposity in male rats, whereas risperidone treatment resulted in a transient reduction in food intake and significantly reduced body weight gain compared to vehicle-treated control rats. Whereas neither antipsychotic had any effect on serum lipid profiles, glucose tolerance or the circulating concentrations of hormones controlled by the hypothalamo-pituitary-thyroid (free T4), -adrenal (corticosterone), -somatotropic (IGF-1), or -gonadotropic axes (testosterone), haloperidol increased circulating insulin levels and risperidone increased serum glucagon levels. This finding suggests that haloperidol or risperidone induce distinct metabolic effects. Since metabolic disorders such as obesity and type 2 diabetes mellitus represent serious health issues, understanding antipsychotic-induced endocrine and metabolic effects may ultimately allow better control of these side effects.


Asunto(s)
Antipsicóticos/toxicidad , Sistema Endocrino/efectos de los fármacos , Haloperidol/toxicidad , Hiperinsulinismo/inducido químicamente , Risperidona/toxicidad , Tejido Adiposo/efectos de los fármacos , Animales , Antipsicóticos/administración & dosificación , Antipsicóticos/farmacología , Apetito/efectos de los fármacos , Peso Corporal/efectos de los fármacos , Corticosterona/metabolismo , Diabetes Mellitus Tipo 2/inducido químicamente , Diabetes Mellitus Tipo 2/prevención & control , Ingestión de Energía/efectos de los fármacos , Glucagón/metabolismo , Haloperidol/administración & dosificación , Haloperidol/farmacología , Insulina/metabolismo , Resistencia a la Insulina , Secreción de Insulina , Metabolismo de los Lípidos/efectos de los fármacos , Masculino , Obesidad/inducido químicamente , Obesidad/prevención & control , Ratas , Ratas Sprague-Dawley , Risperidona/administración & dosificación , Risperidona/farmacología , Especificidad de la Especie , Testosterona/metabolismo , Aumento de Peso/efectos de los fármacos
17.
Clin Cancer Res ; 11(18): 6431-41, 2005 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-16166417

RESUMEN

PURPOSE: Persistent interleukin-8 (IL-8) production contributes to chronic inflammation of the stomach. The proinflammatory IL-1beta polymorphisms, which enhance the cytokine production, are associated with increased risk of gastric cancer. The -251A/T polymorphism of the IL-8 promoter is involved in several human diseases. Particularly, the -251A is associated with decreased risk of colorectal cancer. We aimed to determine whether the -251 allele resulting in high IL-8 expression was associated with increased risk of gastric carcinoma. EXPERIMENTAL DESIGN: The -251A/T promoters were cloned and analyzed by luciferase assay. Binding of nuclear proteins to the -251A/T promoters was analyzed by electrophoretic mobility shift assay. The -251A/T promoters were differentiated by PCR-RFLP. Comparison of gastric cancer risk between the -251A/T promoters was done by a case-control study. RESULTS: The -251T allele possessed transcriptional activity 2- to 5-fold stronger than the -251A counterpart. Electrophoretic mobility shift assay showed that the -251A promoter had strong ability to bind to an unknown protein or multiprotein complex. The -251T allele was associated with increased risk of noncardia (P(trend) = 0.012) and cardia (P(trend) = 0.029) carcinomas. Gastric carcinoma patients with the low-risk AA genotype had a tendency to sustain intestinal-type carcinomas (chi(2) = 6.816; P = 0.033); however, the high-risk -251T allele was associated with >2-fold increased risk of diffuse-type (AA versus AT + TT: odds ratio, 2.52; 95% confidence interval, 1.16-5.49; P = 0.017) and mixed-type (AA versus AT + TT: odds ratio, 2.22; 95% confidence interval, 1.12-4.40; P = 0.019) carcinomas. CONCLUSIONS: The IL-8 -251T allele is significantly associated with increased risk of gastric carcinoma, particularly the diffuse and mixed types in Chinese population.


Asunto(s)
Interleucina-8/genética , Regiones Promotoras Genéticas/genética , Neoplasias Gástricas/patología , Adulto , Anciano , Alelos , Secuencia de Bases , Estudios de Casos y Controles , Línea Celular Tumoral , Distribución de Chi-Cuadrado , China , Femenino , Frecuencia de los Genes , Genotipo , Infecciones por Helicobacter/genética , Infecciones por Helicobacter/microbiología , Helicobacter pylori , Humanos , Masculino , Persona de Mediana Edad , Oportunidad Relativa , Polimorfismo de Nucleótido Simple , Factores de Riesgo , Neoplasias Gástricas/genética , Neoplasias Gástricas/microbiología , Células Tumorales Cultivadas
18.
Cancer Immunol Res ; 4(6): 488-497, 2016 06.
Artículo en Inglés | MEDLINE | ID: mdl-27045020

RESUMEN

Macroenvironmental factors, including a patient's physical and social environment, play a role in cancer risk and progression. Our previous studies show that living in an enriched environment (EE) providing complex stimuli confers an anticancer phenotype in mice mediated, in part by a specific neuroendocrine axis, with brain-derived neurotrophic factor (BDNF) as the key brain mediator. Here, we investigated how an EE modulated T-cell immunity and its role in the EE-induced anticancer effects. Our data demonstrated that CD8 T cells were required to mediate the anticancer effects of an EE in an orthotropic model of melanoma. In secondary lymphoid tissue (SLT), an EE induced early changes in the phenotype of T-cell populations, characterized by a decrease in the ratio of CD4 T helper to CD8 cytotoxic T lymphocytes (CTL). Overexpression of hypothalamic BDNF reproduced EE-induced T-cell phenotypes in SLT, whereas knockdown of hypothalamic BDNF inhibited EE-induced immune modulation in SLT. Both propranolol and mifepristone blocked the EE-associated modulation of CTLs in SLT, suggesting that both the sympathetic nervous system and the hypothalamic-pituitary-adrenal axis were involved. Our results demonstrated that enhanced anticancer effect of an EE was mediated at least in part through modulation of T-cell immunity and provided support to the emerging concept of manipulating a single gene in the brain to improve cancer immunotherapy. Cancer Immunol Res; 4(6); 488-97. ©2016 AACR.


Asunto(s)
Factor Neurotrófico Derivado del Encéfalo/metabolismo , Interacción Gen-Ambiente , Hipotálamo/metabolismo , Melanoma Experimental/inmunología , Subgrupos de Linfocitos T/inmunología , Antagonistas Adrenérgicos beta/farmacología , Animales , Factor Neurotrófico Derivado del Encéfalo/deficiencia , Linfocitos T CD8-positivos/inmunología , Vivienda para Animales , Inmunidad Celular/efectos de los fármacos , Inmunidad Celular/genética , Inmunidad Celular/inmunología , Inmunofenotipificación , Masculino , Melanoma Experimental/genética , Melanoma Experimental/patología , Ratones Endogámicos C57BL , Trasplante de Neoplasias , Propranolol/farmacología , Transducción de Señal/inmunología , Linfocitos T Citotóxicos/inmunología
19.
J Bone Miner Res ; 20(10): 1851-7, 2005 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-16160743

RESUMEN

UNLABELLED: Leptin and Y2 receptors on hypothalamic NPY neurons mediate leptin effects on energy homeostasis; however, their interaction in modulating osteoblast activity is not established. Here, direct testing of this possibility indicates distinct mechanisms of action for leptin anti-osteogenic and Y2-/- anabolic pathways in modulating bone formation. INTRODUCTION: Central enhancement of bone formation by hypothalamic neurons is observed in leptin-deficient ob/ob and Y2 receptor null mice. Similar elevation in central neuropeptide Y (NPY) expression and effects on osteoblast activity in these two models suggest a shared pathway between leptin and Y2 receptors in the central control of bone physiology. The aim of this study was to test whether the leptin and Y2 receptor pathways regulate bone by the same or distinct mechanisms. MATERIALS AND METHODS: The interaction of concomitant leptin and Y2 receptor deficiency in controlling bone was examined in Y2-/- ob/ob double mutant mice, to determine whether leptin and Y2 receptor deficiency have additive effects. Interaction between leptin excess and Y2 receptor deletion was examined using recombinant adeno-associated viral vector overproduction of NPY (AAV-NPY) to produce weight gain and thus leptin excess in adult Y2-/- mice. Cancellous bone volume and bone cell function were assessed. RESULTS: Osteoblast activity was comparably elevated in ob/ob, Y2-/-, and Y2-/- ob/ob mice. However, greater bone resorption in ob/ob and Y2-/- ob/ob mice reduced cancellous bone volume compared with Y2-/-. Both wildtype and Y2-/- AAV-NPY mice exhibited marked elevation of white adipose tissue accumulation and hence leptin expression, thereby reducing osteoblast activity. Despite this anti-osteogenic leptin effect in the obese AAV-NPY model, osteoblast activity in Y2-/- AAV-NPY mice remained significantly greater than in wildtype AAV-NPY mice. CONCLUSIONS: This study suggests that NPY is not a key regulator of the leptin-dependent osteoblast activity, because both the leptin-deficient stimulation of bone formation and the excess leptin inhibition of bone formation can occur in the presence of high hypothalamic NPY. The Y2-/- pathway acts consistently to stimulate bone formation; in contrast, leptin continues to suppress bone formation as circulating levels increase. As a result, they act increasingly in opposition as obesity becomes more marked. Thus, in the absence of leptin, the cancellous bone response to loss of Y2 receptor and leptin activity can not be distinguished. However, as leptin levels increase to physiological levels, distinct signaling pathways are revealed.


Asunto(s)
Metabolismo Energético/fisiología , Hipotálamo/metabolismo , Leptina/metabolismo , Osteogénesis/fisiología , Receptores de Neuropéptido Y/metabolismo , Transducción de Señal/fisiología , Animales , Leptina/deficiencia , Ratones , Ratones Noqueados , Neuropéptido Y/metabolismo , Osteoblastos/metabolismo , Receptores de Leptina , Receptores de Neuropéptido Y/genética
20.
J Neurosci ; 24(12): 3051-9, 2004 Mar 24.
Artículo en Inglés | MEDLINE | ID: mdl-15044544

RESUMEN

Neuropeptide Y (NPY) inhibits seizures in experimental models and reduces excitability in human epileptic tissue. We studied the effect of long-lasting NPY overexpression in the rat hippocampus with local application of recombinant adeno-associated viral (AAV) vectors on acute kainate seizures and kindling epileptogenesis. Transgene expression was significantly increased by 7 d, reached maximal expression by 2 weeks, and persisted for at least 3 months. Serotype 2 AAV vector increased NPY expression in hilar interneurons, whereas the chimeric serotype 1/2 vector caused far more widespread expression, also including mossy fibers, pyramidal cells, and the subiculum. EEG seizures induced by intrahippocampal kainate were reduced by 50-75%, depending on the vector serotype, and seizure onset was markedly delayed. In rats injected with the chimeric serotype 1/2 vector, status epilepticus was abolished, and kindling acquisition was significantly delayed. Thus, targeted NPY gene transfer provides a potential therapeutic principle for the treatment of drug-resistant partial epilepsies.


Asunto(s)
Epilepsia/terapia , Terapia Genética/métodos , Vectores Genéticos/administración & dosificación , Hipocampo/fisiopatología , Neuropéptido Y/biosíntesis , Animales , Dependovirus/genética , Modelos Animales de Enfermedad , Electroencefalografía/efectos de los fármacos , Epilepsia/fisiopatología , Epilepsia/prevención & control , Expresión Génica , Técnicas de Transferencia de Gen , Vectores Genéticos/genética , Hipocampo/efectos de los fármacos , Hipocampo/metabolismo , Inyecciones Intraventriculares , Ácido Kaínico , Excitación Neurológica , Masculino , Neuropéptido Y/genética , Neuropéptido Y/uso terapéutico , Ratas , Ratas Sprague-Dawley , Convulsiones/inducido químicamente , Convulsiones/fisiopatología , Convulsiones/prevención & control , Resultado del Tratamiento
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