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1.
J Hum Nutr Diet ; 2024 Aug 04.
Artículo en Inglés | MEDLINE | ID: mdl-39099188

RESUMEN

BACKGROUND: To improve the healthfulness of foods offered while accelerating the use of environmental sustainability practices, it is important to engage hospital food service operators in the adoption of such practices. The purpose of this study was to explore barriers, facilitators and best practices for implementing environmental sustainability standards in food service among veterans affairs (VA) hospitals in the United States. METHODS: We conducted an online survey with 14 VA hospital food service directors and then 11 qualitative interviews. The survey assessed motivations for initiating sustainability standards and included a self-rating of implementation for each of five standards: increasing plant-forward dishes, procuring and serving sustainable foods that meet organic/fair trade and other certifications, procuring and serving locally produced foods, reducing food waste and reducing energy consumption. Interviews were transcribed verbatim. Qualitative analysis, including coding of themes and subthemes, was conducted by two coders to determine barriers, facilitators and best practices for each of these five standards. Quantitative methods (counts and frequencies) were used to analyse the survey data. RESULTS: Participants had an average of 5 years of experience implementing sustainability standards. The top three motivators cited were reducing food waste, serving healthier foods and increasing efficiency or cost savings. Barriers revolved around patient preferences, contractual difficulties and costs related to reducing waste. Facilitators included taste testing new recipes that include more sustainable food options and easy access to sustainable products from the prime vendor. Best practices included making familiar dishes plant-forward and plate waste studies to prevent overproduction. CONCLUSIONS: Although there were many barriers to implementation, food service directors had solutions for overcoming challenges and implementing food service sustainability standards, which can be tested in future sustainability initiatives.

2.
Early Child Res Q ; 68: 99-111, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38855311

RESUMEN

Young children rapidly learn facts about the world. One mechanism supporting knowledge acquisition is memory integration: derivation of new knowledge by combining separate, yet related facts accumulated over time. There are both developmental changes and individual differences in young children's learning through memory integration. However, there is little research on how everyday social interactions may promote memory integration and contribute to individual differences. Accordingly, we investigated how the everyday social interactions of caregiver-child shared book reading support 5- to 6-year-olds' memory integration (N = 82 parent-child dyads; 47 female children; M age 6.10; 56.5% White non-Latinx, 15% Black, 6% White Latinx, 5.5% Asian, 17% more than one race). Caregivers read a narrative book that included opportunities to integrate facts. Half the dyads were assigned to an embedded questions condition (questions on facts included throughout the book) and half to a no embedded questions condition (statements only). We measured dyads' extratextual talk while reading for the extent to which they integrated the facts (integration talk). Children's learning was tested with both memory integration and fact recall questions. Dyads in the embedded questions condition had more integration talk. The extent to which the dyads integrated while reading predicted children's integration performance, above and beyond condition effects. This effect was specific to memory integration: integration talk nor condition accounted for fact recall. These results suggest that shared book reading can support young children's integration, especially when books engage dyads through embedded questions and dyads integrate facts while reading.

3.
BMC Med Ethics ; 24(1): 49, 2023 07 08.
Artículo en Inglés | MEDLINE | ID: mdl-37422629

RESUMEN

BACKGROUND: It has been argued that ethics review committees-e.g., Research Ethics Committees, Institutional Review Boards, etc.- have weaknesses in reviewing big data and artificial intelligence research. For instance, they may, due to the novelty of the area, lack the relevant expertise for judging collective risks and benefits of such research, or they may exempt it from review in instances involving de-identified data. MAIN BODY: Focusing on the example of medical research databases we highlight here ethical issues around de-identified data sharing which motivate the need for review where oversight by ethics committees is weak. Though some argue for ethics committee reform to overcome these weaknesses, it is unclear whether or when that will happen. Hence, we argue that ethical review can be done by data access committees, since they have de facto purview of big data and artificial intelligence projects, relevant technical expertise and governance knowledge, and already take on some functions of ethical review. That said, like ethics committees, they may have functional weaknesses in their review capabilities. To strengthen that function, data access committees must think clearly about the kinds of ethical expertise, both professional and lay, that they draw upon to support their work. CONCLUSION: Data access committees can undertake ethical review of medical research databases provided they enhance that review function through professional and lay ethical expertise.


Asunto(s)
Inteligencia Artificial , Investigación Biomédica , Humanos , Revisión Ética , Comités de Ética , Comités de Ética en Investigación , Difusión de la Información
4.
J Med Internet Res ; 25: e38039, 2023 04 24.
Artículo en Inglés | MEDLINE | ID: mdl-37093631

RESUMEN

BACKGROUND: There is increasing interest in the use of artificial intelligence (AI) in pathology to increase accuracy and efficiency. To date, studies of clinicians' perceptions of AI have found only moderate acceptability, suggesting the need for further research regarding how to integrate it into clinical practice. OBJECTIVE: The aim of the study was to determine contextual factors that may support or constrain the uptake of AI in pathology. METHODS: To go beyond a simple listing of barriers and facilitators, we drew on the approach of realist evaluation and undertook a review of the literature to elicit stakeholders' theories of how, for whom, and in what circumstances AI can provide benefit in pathology. Searches were designed by an information specialist and peer-reviewed by a second information specialist. Searches were run on the arXiv.org repository, MEDLINE, and the Health Management Information Consortium, with additional searches undertaken on a range of websites to identify gray literature. In line with a realist approach, we also made use of relevant theory. Included documents were indexed in NVivo 12, using codes to capture different contexts, mechanisms, and outcomes that could affect the introduction of AI in pathology. Coded data were used to produce narrative summaries of each of the identified contexts, mechanisms, and outcomes, which were then translated into theories in the form of context-mechanism-outcome configurations. RESULTS: A total of 101 relevant documents were identified. Our analysis indicates that the benefits that can be achieved will vary according to the size and nature of the pathology department's workload and the extent to which pathologists work collaboratively; the major perceived benefit for specialist centers is in reducing workload. For uptake of AI, pathologists' trust is essential. Existing theories suggest that if pathologists are able to "make sense" of AI, engage in the adoption process, receive support in adapting their work processes, and can identify potential benefits to its introduction, it is more likely to be accepted. CONCLUSIONS: For uptake of AI in pathology, for all but the most simple quantitative tasks, measures will be required that either increase confidence in the system or provide users with an understanding of the performance of the system. For specialist centers, efforts should focus on reducing workload rather than increasing accuracy. Designers also need to give careful thought to usability and how AI is integrated into pathologists' workflow.


Asunto(s)
Inteligencia Artificial , Narración , Humanos , Aprendizaje Automático , Patología
5.
Diabet Med ; 39(12): e14963, 2022 12.
Artículo en Inglés | MEDLINE | ID: mdl-36256487

RESUMEN

INTRODUCTION: Fibrosis of renal tubules is the final common pathway in diabetic nephropathy and develops in the face of tubular injury and fibroblast activation. Aberrant connexin 43 (Cx43) hemichannel activity has been linked to this damage under euglycaemic conditions, however, its role in glycaemic injury is unknown. This study investigated the effect of a Cx43 blocker (Tonabersat) on hemichannel activity and cell-cell interactions within and between tubular epithelial cells and fibroblasts in an in vitro model of diabetic nephropathy. METHODS: Human kidney (HK2) proximal tubule epithelial cells and medullary fibroblasts (TK173) were treated in low (5 mM) or high (25 mM) glucose ± transforming growth factor beta-1 (TGFß1) ± Tonabersat in high glucose. Carboxyfluorescein dye uptake and ATPlite luminescence assessed changes in hemichannel-mediated ATP release, while immunoblotting determined protein expression. Co-incubation with the ATP-diphosphohydrolase apyrase or a P2X7R inhibitor (A438079) assessed ATP-P2X7R signalling. Indirect co-culture with conditioned media from the alternate cell type evaluated paracrine-mediated heterotypic interactions. RESULTS: Tonabersat partially negated glucose/TGFß1-induced increases in Cx43 hemichannel-mediated ATP release and downstream changes in adherens junction and extracellular matrix (ECM) protein expression in HK2 and TK173 cells. Apyrase and A438079 highlighted the role for ATP-P2X7R in driving changes in protein expression in TK173 fibroblasts. Indirect co-culture studies suggest that epithelial cell secretome increases Tonabersat-sensitive hemichannel-mediated dye uptake in fibroblasts and downstream protein expression. CONCLUSION: Tonabersat-sensitive hemichannel-mediated ATP release enhances TGFß1-driven heterotypic cell-cell interaction and favours myofibroblast activation. The data supports the potential benefit of Cx43 inhibition in reducing tubulointerstitial fibrosis in late-stage diabetic nephropathy.


Asunto(s)
Diabetes Mellitus , Nefropatías Diabéticas , Humanos , Adenosina Trifosfato/metabolismo , Adenosina Trifosfato/farmacología , Apirasa/metabolismo , Apirasa/farmacología , Comunicación , Conexina 43/metabolismo , Diabetes Mellitus/metabolismo , Nefropatías Diabéticas/metabolismo , Células Epiteliales/metabolismo , Fibroblastos/metabolismo , Fibrosis , Glucosa/farmacología
6.
Public Health Nutr ; : 1-14, 2022 Feb 07.
Artículo en Inglés | MEDLINE | ID: mdl-35125128

RESUMEN

OBJECTIVE: Describe nutrition and physical activity practices, nutrition self-efficacy and barriers and food programme knowledge within Family Child Care Homes (FCCH) and differences by staffing. DESIGN: Baseline, cross-sectional analyses of the Happy Healthy Homes randomised trial (NCT03560050). SETTING: FCCH in Oklahoma, USA. PARTICIPANTS: FCCH providers (n 49, 100 % women, 30·6 % Non-Hispanic Black, 2·0 % Hispanic, 4·1 % American Indian/Alaska Native, 51·0 % Non-Hispanic white, 44·2 ± 14·2 years of age. 53·1 % had additional staff) self-reported nutrition and physical activity practices and policies, nutrition self-efficacy and barriers and food programme knowledge. Differences between providers with and without additional staff were adjusted for multiple comparisons (P < 0·01). RESULTS: The prevalence of meeting all nutrition and physical activity best practices ranged from 0·0-43·8 % to 4·1-16·7 %, respectively. Average nutrition and physical activity scores were 3·2 ± 0·3 and 3·0 ± 0·5 (max 4·0), respectively. Sum nutrition and physical activity scores were 137·5 ± 12·6 (max 172·0) and 48·4 ± 7·5 (max 64·0), respectively. Providers reported high nutrition self-efficacy and few barriers. The majority of providers (73·9-84·7 %) felt that they could meet food programme best practices; however, knowledge of food programme best practices was lower than anticipated (median 63-67 % accuracy). More providers with additional staff had higher self-efficacy in family-style meal service than did those who did not (P = 0·006). CONCLUSIONS: Providers had high self-efficacy in meeting nutrition best practices and reported few barriers. While providers were successfully meeting some individual best practices, few met all. Few differences were observed between FCCH providers with and without additional staff. FCCH providers need additional nutrition training on implementation of best practices.

7.
BMC Public Health ; 22(1): 1487, 2022 08 05.
Artículo en Inglés | MEDLINE | ID: mdl-35927692

RESUMEN

BACKGROUND: Guidelines promoting healthy lifestyles are cornerstones of chronic disease prevention and treatment. The purpose of this study is to investigate independent and joint associations of five key health behaviors with health outcomes (body mass index (BMI kg/m2) and depressive symptoms) in adult twins. METHODS: We included 6,048 twin pairs from a community-based registry. Five key health behaviors were: (1) ≥ 8 h of sleep per night, (2) ≥ 5 servings of fruits and vegetables daily, (3) ≤ 2 h sedentary time per day, (4) ≥ 150 min of moderate-to-vigorous physical activity (MVPA) per week, and (5) no smoking. We analyzed phenotypic associations between behaviors and outcomes; whether phenotypic associations were confounded by additive genetic and shared environmental factors within twin pairs ("quasi-causal" associations); and which behaviors, considered simultaneously, had the largest associations with outcomes. RESULTS: We found negative phenotypic associations between number of behaviors achieved with BMI and depressive symptoms score (ps < 0.05). Associations remained significant, though attenuated, when controlling for genetic and shared environmental factors, and demographics, for depressive symptoms score but not BMI (p < 0.05). Quantitative variable importance measures derived from regression tree models showed sedentary time and MVPA were the most important variables in partitioning twins with different BMI, and smoking and sedentary time for partitioning twins with different depressive symptoms score. CONCLUSIONS: Achievement of commonly endorsed health behaviors is associated with lower BMI (especially sedentary and MVPA targets) and depressive symptoms score (especially sedentary and smoking targets). This provides further support of health behavior promotion to improve health outcomes.


Asunto(s)
Depresión , Conducta Sedentaria , Adulto , Índice de Masa Corporal , Estudios Transversales , Depresión/epidemiología , Humanos , Estilo de Vida
8.
Int J Mol Sci ; 23(2)2022 Jan 06.
Artículo en Inglés | MEDLINE | ID: mdl-35054783

RESUMEN

Of increasing prevalence, diabetes is characterised by elevated blood glucose and chronic inflammation that precedes the onset of multiple secondary complications, including those of the kidney and the eye. As the leading cause of end stage renal disease and blindness in the working population, more than ever is there a demand to develop clinical interventions which can both delay and prevent disease progression. Connexins are membrane bound proteins that can form pores (hemichannels) in the cell membrane. Gated by cellular stress and injury, they open under pathophysiological conditions and in doing so release 'danger signals' including adenosine triphosphate into the extracellular environment. Linked to sterile inflammation via activation of the nod-like receptor protein 3 inflammasome, targeting aberrant hemichannel activity and the release of these danger signals has met with favourable outcomes in multiple models of disease, including secondary complications of diabetes. In this review, we provide a comprehensive update on those studies which document a role for aberrant connexin hemichannel activity in the pathogenesis of both diabetic eye and kidney disease, ahead of evaluating the efficacy of blocking connexin-43 specific hemichannels in these target tissues on tissue health and function.


Asunto(s)
Conexina 43/metabolismo , Complicaciones de la Diabetes/terapia , Ojo/patología , Inflamación/metabolismo , Inflamación/terapia , Riñón/patología , Animales , Humanos , Microvasos/patología
9.
Toxicol Pathol ; 49(4): 720-737, 2021 06.
Artículo en Inglés | MEDLINE | ID: mdl-33297858

RESUMEN

With advancements in whole slide imaging technology and improved understanding of the features of pathologist workstations required for digital slide evaluation, many institutions are investigating broad digital pathology adoption. The benefits of digital pathology evaluation include remote access to study or diagnostic case materials and integration of analysis and reporting tools. Diagnosis based on whole slide images is established in human medical pathology, and the use of digital pathology in toxicologic pathology is increasing. However, there has not been broad adoption in toxicologic pathology, particularly in the context of regulatory studies, due to lack of precedence. To address this topic, as well as practical aspects, the European Society of Toxicologic Pathology coordinated an expert international workshop to assess current applications and challenges and outline a set of minimal requirements needed to gain future regulatory acceptance for the use of digital toxicologic pathology workflows in research and development, so that toxicologic pathologists can benefit from digital slide technology.

10.
J Paediatr Child Health ; 57(7): 1031-1036, 2021 07.
Artículo en Inglés | MEDLINE | ID: mdl-33571379

RESUMEN

AIM: This study aimed to assess the relationship between the family environment and behaviours with objective child sleep quality. METHODS: Twenty-four children (aged 2-5 years) and their parents participated. Child sleep was assessed by accelerometer. Health of the family environment was quantified using the Family Nutrition and Physical Activity Screening Tool (FNPA). Exact Wilcoxon rank sum tests and linear regression were used to determine associations between FNPA scores and child sleep. RESULTS: Healthier Total FNPA, Physical Activity FNPA, and Sleep Routine scores were associated with earlier bedtime. Healthier Sleep Routine score was associated with more total minutes of sleep per night. Healthier screen time-related FNPA construct scores were associated with earlier bedtime. CONCLUSIONS: A composite score of family environment and behaviours, including physical activity- and nutrition-related constructs, was related to child sleep quality. Focus should be placed on the obesogenic family environment and healthy sleep routines to promote overall health among pre-school-aged populations.


Asunto(s)
Ejercicio Físico , Estado Nutricional , Índice de Masa Corporal , Niño , Preescolar , Familia , Humanos , Sueño
11.
Int J Mol Sci ; 22(6)2021 Mar 10.
Artículo en Inglés | MEDLINE | ID: mdl-33802083

RESUMEN

Chronic kidney disease (CKD) is a global health problem associated with a number of comorbidities. Recent evidence implicates increased hemichannel-mediated release of adenosine triphosphate (ATP) in the progression of tubulointerstitial fibrosis, the main underlying pathology of CKD. Here, we evaluate the effect of danegaptide on blocking hemichannel-mediated changes in the expression and function of proteins associated with disease progression in tubular epithelial kidney cells. Primary human proximal tubule epithelial cells (hPTECs) were treated with the beta1 isoform of the pro-fibrotic cytokine transforming growth factor (TGFß1) ± danegaptide. qRT-PCR and immunoblotting confirmed mRNA and protein expression, whilst a cytokine antibody array assessed the expression/secretion of proinflammatory and profibrotic cytokines. Carboxyfluorescein dye uptake and ATP biosensing measured hemichannel activity and ATP release, whilst transepithelial electrical resistance was used to assess paracellular permeability. Danegaptide negated carboxyfluorescein dye uptake and ATP release and protected against protein changes associated with tubular injury. Blocking Cx43-mediated ATP release was paralleled by partial restoration of the expression of cell cycle inhibitors, adherens and tight junction proteins and decreased paracellular permeability. Furthermore, danegaptide inhibited TGFß1-induced changes in the expression and secretion of key adipokines, cytokines, chemokines, growth factors and interleukins. The data suggest that as a gap junction modulator and hemichannel blocker, danegaptide has potential in the future treatment of CKD.


Asunto(s)
Dipéptidos/farmacología , Células Epiteliales , Túbulos Renales Proximales , Insuficiencia Renal Crónica , Factor de Crecimiento Transformador beta1/metabolismo , Línea Celular , Células Epiteliales/metabolismo , Células Epiteliales/patología , Humanos , Túbulos Renales Proximales/lesiones , Túbulos Renales Proximales/metabolismo , Túbulos Renales Proximales/patología , Insuficiencia Renal Crónica/tratamiento farmacológico , Insuficiencia Renal Crónica/metabolismo , Insuficiencia Renal Crónica/patología
12.
Pathologica ; 113(5): 305-306, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-34837088

RESUMEN

Juan Rosai, the "Maradona" of surgical pathology, played a role not only as a diagnostician but also as a researcher, a consultant and a teacher, distinguishing himself as a real icon at all levels of modern pathology. He was an innovative promoter of emerging technologies including digital pathology.These few lines commemorate the digital side of the "Maestro" Juan Rosai from a junior's perspective highlighting how Rosai supported digital pathology and remembering that, according to his own words, digital pathology "will revolutionize the field of pathology, if it is not doing that already".


Asunto(s)
Patólogos , Telepatología , Humanos , Masculino
13.
Histopathology ; 76(7): 968-975, 2020 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-31994224

RESUMEN

AIM: The rate of deployment of digital pathology (DP) systems for primary diagnosis in the UK is accelerating. The flexibility and resilience of digital versus standard glass slides could be of great benefit in the NHS breast screening programme (NHSBSP). This study aims to document the safety and benefits of DP for preoperative tissue diagnosis of screen-detected breast lesions. METHODS AND RESULTS: Concordance data for glass and digital slides of the same cases from four sites were subjected to detailed concordance-discordance analysis. A literature review of DP in the primary diagnosis of breast lesions is presented, making this the most comprehensive synthesis of digital breast cancer histopathological diagnostic data to date. Detailed concordance analysis of experimental data from two histopathology departments reveals clinical concordance rates for breast biopsies of 96% (216 of 225) and 99.6% (249 of 250). Data from direct comparison validation studies in two histopathology departments, utilising the protocol recommended by the Royal College of Pathologists, found concordance rates for breast histology cases of 99.4% (180 of 181) and 99.0% (887 of 896). An intraobserver variation study for glass versus digital slides for difficult cases from the NHSBSP yielded a kappa statistic of 0.80, indicating excellent agreement. Discordances encountered in the studies most frequently concerned discrepancies in grading attributable to mitotic count-scoring and identification of weddelite. CONCLUSIONS: The experience of four histopathology laboratories and our review of pre-existing literature suggests that DP is safe for the primary diagnosis of NHSBSP breast histology specimens, and does not increase the risk of misclassification.


Asunto(s)
Neoplasias de la Mama/diagnóstico , Interpretación de Imagen Asistida por Computador/métodos , Patología Clínica/métodos , Femenino , Humanos
14.
Exp Physiol ; 105(2): 219-229, 2020 02.
Artículo en Inglés | MEDLINE | ID: mdl-31785013

RESUMEN

The ability of cells to communicate and synchronise their activity is essential for the maintenance of tissue structure, integrity and function. A family of membrane-bound proteins called connexins are largely responsible for mediating the local transfer of information between cells. Assembled in the cell membrane as a hexameric connexon, they either function as a conduit for paracrine signalling, forming a transmembrane hemi-channel, or, if aligned with connexons on neighbouring cells, form a continuous aqueous pore or gap junction, which allows for the direct transmission of metabolic and electrical signals. Regulation of connexin synthesis and activity is critical to cellular function, and a number of diseases are attributed to changes in the expression and/or function of these important proteins. A link between hyperglycaemia, connexin expression, altered nucleotide concentrations and impaired function highlights a potential role for connexin-mediated cell communication in complications of diabetes. In the diabetic kidney, glycaemic injury is the leading cause of end-stage renal failure, reflecting multiple aetiologies including glomerular hyperfiltration, albuminuria, increased deposition of extracellular matrix and tubulointerstitial fibrosis. Loss of connexin-mediated cell-to-cell communication in diabetic nephropathy may represent an early sign of disease progression, but our understanding of the process remains severely limited. This review focuses on recent evidence demonstrating that glucose-evoked changes in connexin-mediated cell communication and associated purinergic signalling may contribute to the pathogenesis of kidney disease in diabetes, highlighting the tantalising potential of targeting these proteins as a novel therapeutic intervention.


Asunto(s)
Distinciones y Premios , Comunicación Celular/fisiología , Conexinas/metabolismo , Nefropatías Diabéticas/tratamiento farmacológico , Nefropatías Diabéticas/metabolismo , Sistemas de Liberación de Medicamentos/tendencias , Animales , Comunicación Celular/efectos de los fármacos , Sistemas de Liberación de Medicamentos/métodos , Humanos , Hipoglucemiantes/administración & dosificación , Hipoglucemiantes/metabolismo , Riñón/citología , Riñón/efectos de los fármacos , Riñón/metabolismo
15.
Histopathology ; 72(4): 662-671, 2018 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-28940580

RESUMEN

AIM: To train and individually validate a group of breast pathologists in specialty-specific digital primary diagnosis by using a novel protocol endorsed by the Royal College of Pathologists' new guideline for digital pathology. The protocol allows early exposure to live digital reporting, in a risk-mitigated environment, and focuses on patient safety and professional development. METHODS AND RESULTS: Three specialty breast pathologists completed training in the use of a digital microscopy system, and were exposed to a training set of 20 challenging cases, designed to help them identify personal digital diagnostic pitfalls. Following this, the three pathologists viewed a total of 694 live, entire breast cases. All primary diagnoses were made on digital slides, with immediate glass slide review and reconciliation before final case sign-out. There was complete clinical concordance between the glass and digital impression of the case in 98.8% of cases. Only 1.2% of cases had a clinically significant difference in diagnosis/prognosis on glass and digital slide reads. All pathologists elected to continue using the digital microscope as the standard for breast histopathology specimens, with deferral to glass for a limited number of clinical/histological scenarios as a safety net. CONCLUSION: Individual training and validation for digital primary diagnosis allows pathologists to develop competence and confidence in their digital diagnostic skills, and aids safe and responsible transition from the light microscope to the digital microscope.


Asunto(s)
Neoplasias de la Mama/diagnóstico , Educación Médica/métodos , Interpretación de Imagen Asistida por Computador/normas , Patología Clínica/educación , Patología Clínica/normas , Femenino , Humanos , Interpretación de Imagen Asistida por Computador/métodos , Patología Clínica/métodos
16.
Res Sports Med ; 26(2): 147-157, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29376410

RESUMEN

Body mass index (BMI) continues to be used as a marker of health due its strong correlation with adiposity and health. Physical activity (PA) has been shown to be favourably associated with a desirable BMI. Few studies have examined mode of PA participation across BMI indices with a mutually exclusive underweight BMI range. The purpose of this study was to examine the relationship between modes of PA and BMI. Data from the 2015 Behavioral Risk Factor Surveillance System was analysed. Underweight, overweight, and obese BMI categories possessed 35, 20, and 46% lower odds of meeting current PA guidelines. The obese BMI group was found to have lower odds of meeting the aerobic only and strength only guidelines. Underweight, overweight, and obese groups possessed 63, 18, and 76% greater odds of meeting neither PA guideline, respectively.


Asunto(s)
Sistema de Vigilancia de Factor de Riesgo Conductual , Índice de Masa Corporal , Ejercicio Físico , Conductas Relacionadas con la Salud , Adolescente , Adulto , Anciano , Femenino , Adhesión a Directriz , Humanos , Masculino , Persona de Mediana Edad , Obesidad , Sobrepeso , Delgadez , Estados Unidos , Adulto Joven
17.
J Neurophysiol ; 118(6): 3132-3143, 2017 12 01.
Artículo en Inglés | MEDLINE | ID: mdl-28855292

RESUMEN

Self-referencing H+-selective electrodes were used to measure extracellular H+ fluxes from Müller (glial) cells isolated from the tiger salamander retina. A novel chamber enabled stable recordings using H+-selective microelectrodes in a self-referencing format using bicarbonate-based buffer solutions. A small basal H+ flux was observed from the end foot region of quiescent cells bathed in 24 mM bicarbonate-based solutions, and increasing extracellular potassium induced a dose-dependent increase in H+ flux. Barium at 6 mM also increased H+ flux. Potassium-induced extracellular acidifications were abolished when bicarbonate was replaced by 1 mM HEPES. The carbonic anhydrase antagonist benzolamide potentiated the potassium-induced extracellular acidification, while 300 µM DIDS, 300 µM SITS, and 30 µM S0859 significantly reduced the response. Potassium-induced extracellular acidifications persisted in solutions lacking extracellular calcium, although potassium-induced changes in intracellular calcium monitored with Oregon Green were abolished. Exchange of external sodium with choline also eliminated the potassium-induced extracellular acidification. Removal of extracellular sodium by itself induced a transient alkalinization, and replacement of sodium induced a transient acidification, both of which were blocked by 300 µM DIDS. Recordings at the apical portion of the cell showed smaller potassium-induced extracellular H+ fluxes, and removal of the end foot region further decreased the H+ flux, suggesting that the end foot was the major source of acidifications. These studies demonstrate that self-referencing H+-selective electrodes can be used to monitor H+ fluxes from retinal Müller cells in bicarbonate-based solutions and confirm the presence of a sodium-coupled bicarbonate transporter, the activity of which is largely restricted to the end foot of the cell.NEW & NOTEWORTHY The present study uses self-referencing H+-selective electrodes for the first time to measure H+ fluxes from Müller (glial) cells isolated from tiger salamander retina. These studies demonstrate bicarbonate transport as a potent regulator of extracellular levels of acidity around Müller cells and point toward a need for further studies aimed at addressing how such glial cell pH regulatory mechanisms may shape neuronal signaling.


Asunto(s)
Células Ependimogliales/fisiología , Electrodos de Iones Selectos/normas , Microelectrodos/normas , Protones , Ambystoma , Animales , Bario/farmacología , Benzolamida/farmacología , Señalización del Calcio , Células Cultivadas , Células Ependimogliales/efectos de los fármacos , Células Ependimogliales/metabolismo , Concentración de Iones de Hidrógeno , Potasio/farmacología , Sodio/farmacología
18.
BMC Evol Biol ; 16: 16, 2016 Jan 19.
Artículo en Inglés | MEDLINE | ID: mdl-26787507

RESUMEN

BACKGROUND: At a global scale, the temperate zone is highly fragmented both between and within hemispheres. This paper aims to investigate how the world's disjunct temperate zones have been colonised by the pan-temperate plant group Convolvuleae, sampling 148 of the c. 225 known species. We specifically determine the number and timing of amphitropical and transoceanic disjunctions, investigate the extent to which disjunctions in Convolvuleae are spatio-temporally congruent with those in other temperate plant groups and determine the impact of long-distance dispersal events on diversification rates. RESULTS: Eight major disjunctions are observed in Convolvuleae: two Northern Hemisphere, two Southern Hemisphere and four amphitropical. Diversity in the Southern Hemisphere is largely the result of a single colonisation of Africa 3.1-6.4 Ma, and subsequent dispersals from Africa to both Australasia and South America. Speciation rates within this monophyletic, largely Southern Hemisphere group (1.38 species Myr(-1)) are found to be over twice those of the tribe as a whole (0.64 species Myr(-1)). Increased speciation rates are also observed in Calystegia (1.65 species Myr(-1)). CONCLUSIONS: The Convolvuleae has colonised every continent of the world with a temperate biome in c. 18 Myr and eight major range disjunctions underlie this broad distribution. In keeping with other temperate lineages exhibiting disjunct distributions, long-distance dispersal is inferred as the main process explaining the patterns observed although for one American-Eurasian disjunction we cannot exclude vicariance. The colonisation of the temperate zones of the three southern continents within the last c. 4 Myr is likely to have stimulated high rates of diversification recovered in this group, with lineage accumulation rates comparable to those reported for adaptive radiations.


Asunto(s)
Convolvulaceae/fisiología , África , Especies Introducidas , Filogenia , Filogeografía , América del Sur
19.
Ecology ; 97(6): 1518-29, 2016 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-27459782

RESUMEN

Intraspecific diversity, particularly of foundation species, can significantly affect population, community, and ecosystem processes. Examining how genetic diversity relates to demographic traits provides a key mechanistic link from genotypic and phenotypic variation of taxa with complex life histories to their population dynamics. We conducted a field experiment to assess how two metrics of intraspecific diversity (cohort diversity, the number of independent juvenile cohorts created from different adult source populations, and genetic relatedness, genetic similarity among individuals within and across cohorts) affect the survivorship, growth, and recruitment of the foundation species Crassostrea virginica. To assess the effects of both cohort diversity and genetic relatedness on oyster demographic traits under different environmental conditions, we manipulated juvenile oyster diversity and predator exposure (presence/absence of a cage) at two sites differing in resource availability and predation intensity. Differences in predation pressure between sites overwhelmingly determined post-settlement survivorship of oysters. However, in the absence of predation (i.e., cage treatment), one or both metrics of intraspecific diversity, in addition to site, influenced long-term survivorship, growth, and recruitment. While both cohort diversity and genetic relatedness were negatively associated with long-term survivorship, genetic relatedness alone showed a positive association with growth and cohort diversity alone showed a positive association with recruitment. Thus, our results demonstrate that in the absence of predation, intraspecific diversity can affect multiple demographic traits of a foundation species, but the relative importance of these effects depends on the environmental context. Moreover, the magnitude and direction of these effects vary depending on the diversity metric, cohort diversity or genetic relatedness, suggesting that although they are inversely related in this system, each captures sufficiently different components of intraspecific diversity. Given the global loss of oyster reef habitat and rapid decline in oyster population size, our results are particularly relevant to management and restoration. In addition, aquaculture, which commonly excludes predators during early life history stages, may benefit from incorporation of oyster cohort diversity into standard practice.


Asunto(s)
Variación Genética , Ostreidae/fisiología , Animales , Ostreidae/genética , Dinámica Poblacional , Especificidad de la Especie
20.
South Med J ; 109(10): 615-619, 2016 10.
Artículo en Inglés | MEDLINE | ID: mdl-27706496

RESUMEN

OBJECTIVES: Examine the odds of adults reporting physical inactivity (PI) across six body mass index (BMI) categories. METHODS: We used data from the 2013 Behavioral Risk Factor Surveillance System. Six BMI categories were used. RESULTS: The odds of reporting PI in underweight men and men in the class I, II, and III obesity categories were 1.65 (95% confidence interval [CI] 1.35-2.02), 1.30 (95% CI 1.21-1.39), 1.73 (95% CI 1.58-1.90), and 2.44 (95% CI 2.17-2.75), respectively, compared with men of desirable weight (odds ratio [OR] 1.00, 18.5-24.9 kg/m2; referent, OR 1.00). The odds of reporting PI in underweight men were similar to class II and class III obese men. The odds of reporting PI in underweight women, overweight women, and women in the class I, II, and III obesity categories were 1.57 (95% CI 1.36-1.81), 1.20 (95% CI 1.14-1.27), 1.65 (95% CI 1.56-1.75), 2.23 (95% CI 2.07-2.40), and 2.89 (95% CI 2.66-3.15), respectively, compared with women of desirable weight (≥18.5-24.9 kg/m2; referent, OR 1.00). The odds of reporting PI were similar in underweight and class I obese women. Women were found to have greater odds than men of reporting PI in four of the five nondesirable BMI categories (P < 0.05). CONCLUSIONS: The within- and between-sex differences in the odds of reporting PI vary significantly by BMI category. Future research needs to include the underweight BMI category when investigating PI and sedentary time because of the potential clinical relevance.


Asunto(s)
Índice de Masa Corporal , Sobrepeso/epidemiología , Conducta Sedentaria , Delgadez/epidemiología , Adolescente , Adulto , Anciano , Sistema de Vigilancia de Factor de Riesgo Conductual , Femenino , Humanos , Masculino , Persona de Mediana Edad , Factores Sexuales , Estados Unidos/epidemiología , Adulto Joven
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