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1.
Osteoporos Int ; 32(3): 515-527, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32930851

RESUMO

The associations between objective measures of sleep duration and bone outcomes in older men are unknown. No consistent, significant association was identified between sleep duration and bone mineral density (BMD) in the current analysis. However, future research should determine if vitamin D status modifies this relationship. INTRODUCTION: Prior studies, predominantly in women, reported that long and short self-reported sleep duration are associated with lower BMD. Associations between actigraphy-determined sleep duration and BMD or bone turnover markers (BTMs) in older men are unknown. METHODS: Men in The Osteoporotic Fractures in Men (MrOS) Study with wrist actigraphy and concurrent BMD assessment but without comorbidities affecting bone health were included. Sleep duration was considered as a continuous (N = 1926) and dichotomized variable where men were classified as getting the recommended (7-8 h/night; N = 478) or short (< 6 h/night; N = 577) sleep. The cross-sectional association between BMD, BTMs, and sleep duration was examined using a t test or linear regression, where appropriate, in unadjusted and adjusted models. RESULTS: There were no clinically or statistically significant differences in BMD at the L-spine, total hip, or femoral neck between men getting the recommended vs. short sleep duration, using actigraphy or self-reported sleep duration (all p ≥ 0.07). When sleep duration was considered as a continuous variable, femoral neck BMD was higher in men with longer self-reported sleep duration (ß = 0.006 ±0.003, p = 0.02), but this was not significant after further adjustment. In men with low 25OHD (< 20 ng/mL), longer actigraphy-determined sleep duration was associated with higher total hip BMD (ß = 0.016 ± 0.008; p = 0.04). Sleep duration and BTMs were not associated. CONCLUSION: Sleep duration was not associated with hip or L-spine BMD or BTMs in older men. Future research should determine if vitamin D status or other factors modify this relationship.


Assuntos
Densidade Óssea , Colo do Fêmur , Idoso , Estudos Transversais , Feminino , Humanos , Masculino , Sono , Vitamina D
2.
Geophys Res Lett ; 48(22): e2021GL095232, 2021 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-35864979

RESUMO

The 2015 and 2020 ozone holes set record sizes in October-December. We show that these years, as well as other recent large ozone holes, still adhere to a fundamental recovery metric: the later onset of early spring ozone depletion as chlorine and bromine diminishes. This behavior is also captured in the Whole Atmosphere Chemistry Climate Model. We quantify observed recovery trends of the onset of the ozone hole and in the size of the September ozone hole, with good model agreement. A substantial reduction in ozone hole depth during September over the past decade is also seen. Our results indicate that, due to dynamical phenomena, it is likely that large ozone holes will continue to occur intermittently in October-December, but ozone recovery will still be detectable through the later onset, smaller, and less deep September ozone holes: metrics that are governed more by chemical processes.

3.
BMC Med ; 18(1): 221, 2020 07 22.
Artigo em Inglês | MEDLINE | ID: mdl-32693800

RESUMO

BACKGROUND: Involving adults lacking capacity (ALC) in research on end of life care (EoLC) or serious illness is important, but often omitted. We aimed to develop evidence-based guidance on how best to include individuals with impaired capacity nearing the end of life in research, by identifying the challenges and solutions for processes of consent across the capacity spectrum. METHODS: Methods Of Researching End of Life Care_Capacity (MORECare_C) furthers the MORECare statement on research evaluating EoLC. We used simultaneous methods of systematic review and transparent expert consultation (TEC). The systematic review involved four electronic databases searches. The eligibility criteria identified studies involving adults with serious illness and impaired capacity, and methods for recruitment in research, implementing the research methods, and exploring public attitudes. The TEC involved stakeholder consultation to discuss and generate recommendations, and a Delphi survey and an expert 'think-tank' to explore consensus. We narratively synthesised the literature mapping processes of consent with recruitment outcomes, solutions, and challenges. We explored recommendation consensus using descriptive statistics. Synthesis of all the findings informed the guidance statement. RESULTS: Of the 5539 articles identified, 91 met eligibility. The studies encompassed people with dementia (27%) and in palliative care (18%). Seventy-five percent used observational designs. Studies on research methods (37 studies) focused on processes of proxy decision-making, advance consent, and deferred consent. Studies implementing research methods (30 studies) demonstrated the role of family members as both proxy decision-makers and supporting decision-making for the person with impaired capacity. The TEC involved 43 participants who generated 29 recommendations, with consensus that indicated. Key areas were the timeliness of the consent process and maximising an individual's decisional capacity. The think-tank (n = 19) refined equivocal recommendations including supporting proxy decision-makers, training practitioners, and incorporating legislative frameworks. CONCLUSIONS: The MORECare_C statement details 20 solutions to recruit ALC nearing the EoL in research. The statement provides much needed guidance to enrol individuals with serious illness in research. Key is involving family members early and designing study procedures to accommodate variable and changeable levels of capacity. The statement demonstrates the ethical imperative and processes of recruiting adults across the capacity spectrum in varying populations and settings.


Assuntos
Tomada de Decisões/ética , Consentimento Livre e Esclarecido/ética , Transtornos Mentais/psicologia , Projetos de Pesquisa/normas , Assistência Terminal/métodos , Adulto , Consenso , Humanos , Encaminhamento e Consulta , Adulto Jovem
4.
Osteoporos Int ; 30(10): 2087-2098, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31139855

RESUMO

Methodological limitations preclude determination of the association between sleep duration and bone mineral density (BMD) from existing literature. This was the first study to use objective sleep duration to determine its association with BMD. Nocturnal sleep duration, assessed objectively (actigraphy) or subjectively (questionnaire), was not independently associated with BMD in postmenopausal women. INTRODUCTION: Both long and short self-reported sleep durations are associated with low bone mineral density (BMD) in men and women. The association between sleep duration measured by actigraphy and BMD in postmenopausal women is unknown. METHODS: The Study of Osteoporotic Fractures (SOF) ancillary sleep study was used to determine the association between sleep duration and BMD at the total hip and femoral neck in postmenopausal women ≥ 75 years old. Sleep duration was assessed by wrist actigraphy (average 4 nights) and questionnaire. BMD was compared between postmenopausal women with short (< 6 h/night) vs. NIH-recommended (7-8 h/night) sleep durations. Data were analyzed using a 2-sample t test (unadjusted) and multivariate regression model (adjusted). Simple linear regression was used to estimate the difference in BMD per additional hour of sleep when sleep duration was considered as a continuous, rather than dichotomized, variable. RESULTS: Total hip BMD was higher in women with actigraphically assessed shorter sleep duration in unadjusted models only. No clinically or statistically significant differences in total hip or femoral neck BMD were observed according to nocturnal sleep duration after adjusting for body mass index (BMI) in dichotomized (N = 874) or continuous (N = 1624) sleep duration models or when subjective sleep duration was used. When sleep duration included daytime naps, longer sleep duration was associated with lower total hip BMD (ß = - 0.005, p = 0.04). CONCLUSIONS: Nocturnal sleep duration, whether assessed objectively (actigraphy) or subjectively (questionnaire), was not independently associated with BMD in older postmenopausal women.


Assuntos
Densidade Óssea/fisiologia , Pós-Menopausa/fisiologia , Sono/fisiologia , Absorciometria de Fóton/métodos , Actigrafia/métodos , Idoso , Idoso de 80 Anos ou mais , Índice de Massa Corporal , Feminino , Colo do Fêmur/fisiologia , Articulação do Quadril/fisiologia , Humanos , Osteoporose Pós-Menopausa/fisiopatologia , Autorrelato , Inquéritos e Questionários , Fatores de Tempo
5.
Philos Trans A Math Phys Eng Sci ; 377(2151): 20180181, 2019 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-31230570

RESUMO

A current challenge that is facing the plasma wakefield accelerator (PWFA) community is transverse beam emittance preservation. This can be achieved by balancing the natural divergence of the beam against the strong focusing force provided by the PWFA plasma source in a scheme referred to as beam matching. One method to accomplish beam matching is through the gradual focusing of a beam with a plasma density ramp leading into the bulk plasma. Here, the beam dynamics in a Gaussian plasma density ramp are considered, and an empirical formula is identified that gives the ramp length and beam vacuum waist location needed to achieve near-perfect matching. The method uses only the beam vacuum waist beta function as an input. Numerical studies show that the Gaussian ramp focusing formula is robust for beta function demagnification factors spanning more than an order of magnitude with experimentally favourable tolerances for future PWFA research facilities. This article is part of the Theo Murphy meeting issue 'Directions in particle beam-driven plasma wakefield acceleration'.

6.
J Sports Sci ; 37(11): 1235-1241, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30558476

RESUMO

Intermittent exposure to hypoxia can lead to improved endurance performance. Currently, it is unclear whether peripheral adaptions play a role in improving oxygen delivery and utilization following both training and detraining. This study aimed to characterize skeletal muscle blood flow (mBF), oxygen consumption (mV̇O2), and perfusion adaptations to i) 4-weeks handgrip training in hypoxic and normoxic conditions, and ii) following 4-weeks detraining. Using a randomised crossover design, 9 males completed 30-min handgrip training four times a week in hypoxic (14% FiO2 ~ 3250m altitude) and normoxic conditions. mBF, mV̇O2 and perfusion were assessed pre, post 4-weeks training, and following 4-weeks detraining. Hierarchical linear modelling found that mV̇O2 increased at a significantly faster rate (58%) with hypoxic training (0.09 mlO2·min-1 · 100g-1 per week); perfusion increased at a significantly (69%) faster rate with hypoxic training (3.72 µM per week). mBF did not significantly change for the normoxic condition, but there was a significant increase of 0.38 ml· min-1 · 100ml-1 per week (95% CI: 0.35, 0.40) for the hypoxic condition. During 4-weeks detraining, mV̇O2 and perfusion significantly declined at similar rates for both conditions, whereas mBF decreased significantly faster following hypoxic training. Four weeks hypoxic training increases the delivery and utilisation of oxygen in the periphery.


Assuntos
Antebraço/irrigação sanguínea , Hipóxia , Microcirculação , Músculo Esquelético/irrigação sanguínea , Consumo de Oxigênio , Condicionamento Físico Humano/métodos , Adaptação Fisiológica , Estudos Cross-Over , Antebraço/fisiologia , Força da Mão , Hemodinâmica , Humanos , Modelos Lineares , Masculino , Músculo Esquelético/fisiologia , Espectroscopia de Luz Próxima ao Infravermelho , Adulto Jovem
7.
Exp Brain Res ; 236(1): 161-173, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-29098315

RESUMO

Neurophysiological investigations in non-human primates have shown that bi- and tri-modal fronto-parietal neurons exist that respond to touch on the body and visual (and/or auditory) stimuli near the body. The receptive fields of these neurons extend into space around the body, producing a zone wherein multisensory information is readily integrated. This space around the body, known as peripersonal space (PPS), has also been investigated behaviourally in humans. Some studies have focused on how far into depth the spatial boundaries of PPS extend. Most of these investigations have focused on the upper body (e.g., hands, face, trunk), while little is known about the size of PPS for the lower body (i.e. legs and feet). Thus, the aim of the current study was to delineate a PPS boundary around the lower limbs in healthy participants using a multisensory interaction task. Participants made speeded responses to the presence of vibrations applied to the toes while a task-irrelevant visual stimulus approached towards (Experiment 1) or receded from (Experiment 2) the feet. Participants responded significantly faster to tactile stimuli when the visual stimulus was within approximately 73 cm from the feet, but only when it approached (and not receded from) the legs. This is the first study, to our knowledge, to outline the size of PPS for the lower limbs. These findings could provide insight into the mechanisms underlying multisensory integration in the lower limbs, and add to the current body of knowledge on PPS representations.


Assuntos
Pé/fisiologia , Espaço Pessoal , Desempenho Psicomotor/fisiologia , Percepção Espacial/fisiologia , Percepção do Tato/fisiologia , Percepção Visual/fisiologia , Adulto , Feminino , Humanos , Masculino , Adulto Jovem
8.
Transfus Med ; 28(6): 405-412, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30325081

RESUMO

OBJECTIVES: Using a multidisciplinary approach and simulation, a massive transfusion process (MTP) was developed to care for patients in need of emergency transfusion. It was then assessed for effectiveness. BACKGROUND: After a series of sentinel emergency bleeding events, a reliable process for hospital staff to deliver appropriate blood products and obtain relevant laboratory tests to guide therapy for patients with emergency bleeding was needed. METHODS: To determine the feasibility of the new MTP, multidisciplinary teams participated in simulation events. Each simulation event helped refine the MTP. A special laboratory testing panel was devised. To judge the effectiveness and timeliness of the MTP, process measures and patient survival was retrospectively evaluated during the time period before and after MTP implementation. RESULTS: A new emergency bleeding panel of laboratory tests significantly decreased the turn-around time for fibrinogen, haematocrit, International normalised ratio (INR) and platelet count. The speed of commencing the first red blood cells transfusion was also improved (2:00 h vs 0:20 min, P = 0·001). Of 78 patients, there was no change in survival before (n = 31, 48·4%) and after (n = 47, 42·6%; P = 0·6478) MTP implementation. However, there was significant improvement in survival associated with MTP events on the weekdays. CONCLUSIONS: A reliable emergency transfusion process consists of an automatic chain of events that keeps decision-making to a minimum and leads to the fast procurement of blood products and salient test results. This work shows that a multidisciplinary iterative process using simulation increases the efficiency of clinical care delivery for bleeding paediatric and neonatal patients.


Assuntos
Serviços Médicos de Emergência , Transfusão de Eritrócitos , Hemorragia/terapia , Qualidade da Assistência à Saúde , Treinamento por Simulação , Pré-Escolar , Feminino , Hemorragia/sangue , Humanos , Lactente , Recém-Nascido , Coeficiente Internacional Normatizado , Masculino
9.
Skin Res Technol ; 23(4): 500-513, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28295674

RESUMO

BACKGROUND: Experimental work on skin hydration is technologically challenging, and mostly limited to observations where environmental conditions are constant. In some cases, like diapered baby skin, such work is practically unfeasible, yet it is important to understand potential effects of diapering on skin condition. To overcome this challenge, in part, we developed a computer simulation model of reversible transient skin hydration effects. METHODS: Skin hydration model by Li et al. (Chem Eng Sci, 138, 2015, 164) was further developed to simulate transient exposure conditions where relative humidity (RH), wind velocity, air, and skin temperature can be any function of time. Computer simulations of evaporative water loss (EWL) decay after different occlusion times were compared with experimental data to calibrate the model. Next, we used the model to investigate EWL and SC thickness in different diapering scenarios. RESULTS: Key results from the experimental work were: (1) For occlusions by RH=100% and free water longer than 30 minutes the absorbed amount of water is almost the same; (2) Longer occlusion times result in higher water absorption by the SC. The EWL decay and skin water content predictions were in agreement with experimental data. Simulations also revealed that skin under occlusion hydrates mainly because the outflux is blocked, not because it absorbs water from the environment. Further, simulations demonstrated that hydration level is sensitive to time, RH and/or free water on skin. In simulated diapering scenarios, skin maintained hydration content very close to the baseline conditions without a diaper for the entire duration of a 24 hours period. CONCLUSION: Different diapers/diaper technologies are known to have different profiles in terms of their ability to provide wetness protection, which can result in consumer-noticeable differences in wetness. Simulation results based on published literature using data from a number of different diapers suggest that diapered skin hydrates within ranges considered reversible.


Assuntos
Fraldas para Adultos , Fraldas Infantis , Estado de Hidratação do Organismo/fisiologia , Fenômenos Fisiológicos da Pele , Perda Insensível de Água/fisiologia , Simulação por Computador , Desidratação/fisiopatologia , Humanos , Concentração Osmolar , Absorção Cutânea/fisiologia , Água/análise
10.
Int J Obes (Lond) ; 40(12): 1856-1863, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-27534842

RESUMO

BACKGROUND/OBJECTIVES: Androgen deprivation therapy (ADT) is commonly used for treatment of prostate cancer but is associated with side effects, such as sarcopenia and insulin resistance. The role of lifestyle factors such as diet and exercise on insulin sensitivity and body composition in testosterone-deficient males is poorly understood. The aim of the present study was to examine the relationships between androgen status, diet and insulin sensitivity. SUBJECTS/METHODS: Middle-aged (11-12 years old) intact and orchidectomized male rhesus macaques were maintained for 2 months on a standard chow diet and then exposed for 6 months to a Western-style, high-fat/calorie-dense diet (WSD) followed by 4 months of caloric restriction (CR). Body composition, insulin sensitivity, physical activity, serum cytokine levels and adipose biopsies were evaluated before and after each dietary intervention. RESULTS: Both intact and orchidectomized animals gained similar proportions of body fat, developed visceral and subcutaneous adipocyte hypertrophy and became insulin resistant in response to the WSD. CR reduced body fat in both groups but reversed insulin resistance only in intact animals. Orchidectomized animals displayed progressive sarcopenia, which persisted after the switch to CR. Androgen deficiency was associated with increased levels of interleukin-6 and macrophage-derived chemokine (C-C motif chemokine ligand 22), both of which were elevated during CR. Physical activity levels showed a negative correlation with body fat and insulin sensitivity. CONCLUSIONS: Androgen deficiency exacerbated the negative metabolic side effects of the WSD such that CR alone was not sufficient to improve altered insulin sensitivity, suggesting that ADT patients will require additional interventions to reverse insulin resistance and sarcopenia.


Assuntos
Androgênios/deficiência , Composição Corporal/fisiologia , Hipogonadismo/patologia , Resistência à Insulina/fisiologia , Obesidade/patologia , Androgênios/fisiologia , Animais , Restrição Calórica , Dieta Hiperlipídica , Modelos Animais de Doenças , Interleucina-6 , Lipídeos , Macaca mulatta , Masculino , Condicionamento Físico Animal , Receptores Androgênicos
11.
Eur J Appl Physiol ; 116(8): 1479-84, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27255506

RESUMO

UNLABELLED: Rock-climbing performance is largely dependent on the endurance of the forearm flexors. Recently, it was reported that forearm flexor endurance in elite climbers is independent of the ability to regulate conduit artery (brachial) blood flow, suggesting that endurance is not primarily dependent on the ability of the brachial artery to deliver oxygen, but rather the ability of the muscle to perfuse and use oxygen, i.e., skeletal muscle oxidative capacity. PURPOSE: The aim of the study was to determine whether an index of oxidative capacity in the flexor digitorum profundus (FDP) predicts the best sport climbing red-point grade within the last 6 months. Participants consisted of 46 sport climbers with a range of abilities. METHODS: Using near-infrared spectroscopy, the oxidative capacity index of the FDP was assessed by calculating the half-time for tissue oxygen resaturation (O2HTR) following 3-5 min of ischemia. RESULTS: Linear regression, adjusted for age, sex, BMI, and training experience, revealed a 1-s decrease in O2HTR was associated with an increase in red-point grade by 0.65 (95 % CI 0.35-0.94, Adj R (2)  = 0.53). CONCLUSIONS: Considering a grade of 0.4 separated the top four competitors in the 2015 International Federation Sport Climbing World Cup, this finding suggests that forearm flexor oxidative capacity index is an important determinant of rock-climbing performance.


Assuntos
Desempenho Atlético/fisiologia , Tolerância ao Exercício/fisiologia , Antebraço/fisiologia , Montanhismo/fisiologia , Músculo Esquelético/fisiologia , Oxigênio/metabolismo , Adulto , Simulação por Computador , Feminino , Antebraço/irrigação sanguínea , Humanos , Masculino , Microcirculação/fisiologia , Modelos Biológicos , Oxirredução , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Distribuição Tecidual
12.
BMC Neurol ; 15: 218, 2015 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-26499867

RESUMO

BACKGROUND: There is emerging research detailing the relationship between balance/gait/falls and cognition. Imaging studies also suggest a link between structural and functional changes in the frontal lobe (a region commonly associated with cognitive function) and mobility. People with Parkinson's disease have important changes in cognitive function that may impact rehabilitation efficacy. Our underlying hypothesis is that cognitive function and frontal lobe connections with the basal ganglia and brainstem posture/locomotor centers are responsible for postural deficits in people with Parkinson's disease and play a role in rehabilitation efficacy. The purpose of this study is to 1) determine if people with Parkinson's disease can improve mobility and/or cognition after partaking in a cognitively challenging mobility exercise program and 2) determine if cognition and brain circuitry deficits predict responsiveness to exercise rehabilitation. METHODS/DESIGN: This study is a randomized cross-over controlled intervention to take place at a University Balance Disorders Laboratory. The study participants will be people with Parkinson's disease who meet inclusion criteria for the study. The intervention will be 6 weeks of group exercise (case) and 6 weeks of group education (control). The exercise is a cognitively challenging program based on the Agility Boot Camp for people with PD. The education program is a 6-week program to teach people how to better live with a chronic disease. The primary outcome measure is the MiniBESTest and the secondary outcomes are measures of mobility, cognition and neural imaging. DISCUSSION: The results from this study will further our understanding of the relationship between cognition and mobility with a focus on brain circuitry as it relates to rehabilitation potential. TRIAL REGISTRATION: This trial is registered at clinical trials.gov (NCT02231073).


Assuntos
Encéfalo/patologia , Transtornos Cognitivos , Terapia por Exercício/métodos , Avaliação de Resultados em Cuidados de Saúde , Doença de Parkinson , Equilíbrio Postural/fisiologia , Idoso , Idoso de 80 Anos ou mais , Transtornos Cognitivos/diagnóstico , Transtornos Cognitivos/etiologia , Transtornos Cognitivos/reabilitação , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Doença de Parkinson/complicações , Doença de Parkinson/diagnóstico , Doença de Parkinson/reabilitação , Educação de Pacientes como Assunto , Prognóstico
13.
Zoo Biol ; 34(6): 565-75, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26335927

RESUMO

Plant secondary compounds are diverse structurally, and associated biological effects can vary depending on multiple factors including chemical structure and reaction conditions. Phenolic compounds such as tannins can chelate dietary iron, and supplementation of animal species sensitive to iron overload with tannins may prevent/treat iron overload disorder. We assessed the nutrient and phenolic composition and iron-binding capacity of Carolina willow (Salix caroliniana), a plant fed to zoo-managed browsing herbivores. Based on studies in other plant species and the chemical structures of phenolic compounds, we hypothesized that the concentration of condensed tannins in willow would be inversely related to the concentration of phenolic glycosides and directly related to iron-binding capacity. Our results indicated that willow nutrient composition varied by year, season, and plant part, which could be taken into consideration when formulating animal diets. We also found that the predominant plant secondary compounds were condensed tannins with minimal phenolic glycosides. Instead of binding to iron, the willow leaf extracts reduced iron from the ferric to ferrous form, which may have prooxidative effects and increase the bioavailability of iron depending on animal species, gastrointestinal conditions, and whole animal processes. We recommend identifying alternative compounds that effectively chelate iron in vitro and conducting chelation therapy trials in vivo to assess potential effects on iron balance and overall animal health.


Assuntos
Ração Animal/análise , Animais de Zoológico , Dieta/veterinária , Herbivoria , Ferro/metabolismo , Salix/química , Animais , Folhas de Planta/química , Caules de Planta/química
14.
J Pharmacol Exp Ther ; 348(3): 410-20, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24385388

RESUMO

Nicotine, the primary psychoactive component in tobacco smoke, produces its behavioral effects through interactions with neuronal nicotinic acetylcholine receptors (nAChRs). α4ß2 nAChRs are the most abundant in mammalian brain, and converging evidence shows that this subtype mediates the rewarding and reinforcing effects of nicotine. A number of rare variants in the CHRNA4 gene that encode the α4 nAChR subunit have been identified in human subjects and appear to be underrepresented in a cohort of smokers. We compared three of these variants (α4R336C, α4P451L, and α4R487Q) to the common variant to determine their effects on α4ß2 nAChR pharmacology. We examined [(3)H]epibatidine binding, interacting proteins, and phosphorylation of the α4 nAChR subunit with liquid chromatography and tandem mass spectrometry (LC-MS/MS) in HEK 293 cells and voltage-clamp electrophysiology in Xenopus laevis oocytes. We observed significant effects of the α4 variants on nAChR expression, subcellular distribution, and sensitivity to nicotine-induced receptor upregulation. Proteomic analysis of immunopurified α4ß2 nAChRs incorporating the rare variants identified considerable differences in the intracellular interactomes due to these single amino acid substitutions. Electrophysiological characterization in X. laevis oocytes revealed alterations in the functional parameters of activation by nAChR agonists conferred by these α4 rare variants, as well as shifts in receptor function after incubation with nicotine. Taken together, these experiments suggest that genetic variation at CHRNA4 alters the assembly and expression of human α4ß2 nAChRs, resulting in receptors that are more sensitive to nicotine exposure than those assembled with the common α4 variant. The changes in nAChR pharmacology could contribute to differences in responses to smoked nicotine in individuals harboring these rare variants.


Assuntos
Receptores Nicotínicos/metabolismo , Animais , Compostos Bicíclicos Heterocíclicos com Pontes/farmacologia , Membrana Celular/metabolismo , Feminino , Células HEK293 , Humanos , Nicotina/farmacologia , Agonistas Nicotínicos/farmacologia , Oócitos/fisiologia , Fosforilação , Polimorfismo Genético , Subunidades Proteicas/genética , Subunidades Proteicas/metabolismo , Piridinas/farmacologia , Receptores Nicotínicos/genética , Regulação para Cima , Xenopus laevis
15.
Int J Obes (Lond) ; 38(9): 1159-64, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24458262

RESUMO

BACKGROUND: Reduced sleep duration has been increasingly reported to predict obesity. However, timing and regularity of sleep may also be important. In this study, the cross-sectional association between objectively measured sleep patterns and obesity was assessed in two large cohorts of older individuals. METHODS: Wrist actigraphy was performed in 3053 men (mean age: 76.4 years) participating in the Osteoporotic Fractures in Men Study and 2985 women (mean age: 83.5 years) participating in the Study of Osteoporotic Fractures. Timing and regularity of sleep patterns were assessed across nights, as well as daytime napping. RESULTS: Greater night-to-night variability in sleep duration and daytime napping were associated with obesity independent of mean nocturnal sleep duration in both men and women. Each 1 h increase in the standard deviation of nocturnal sleep duration increased the odds of obesity 1.63-fold (95% confidence interval: 1.31-2.02) among men and 1.22-fold (95% confidence interval: 1.01-1.47) among women. Each 1 h increase in napping increased the odds of obesity 1.23-fold (95% confidence interval: 1.12-1.37) in men and 1.29-fold (95% confidence interval: 1.17-1.41) in women. In contrast, associations between later sleep timing and night-to-night variability in sleep timing with obesity were less consistent. CONCLUSIONS: In both older men and women, variability in nightly sleep duration and daytime napping were associated with obesity, independent of mean sleep duration. These findings suggest that characteristics of sleep beyond mean sleep duration may have a role in weight homeostasis, highlighting the complex relationship between sleep and metabolism.


Assuntos
Obesidade/etiologia , Privação do Sono/complicações , Sono , Distribuição por Idade , Idoso , Idoso de 80 Anos ou mais , Análise de Variância , Índice de Massa Corporal , Ritmo Circadiano , Estudos Transversais , Feminino , Humanos , Masculino , Obesidade/epidemiologia , Obesidade/metabolismo , Obesidade/fisiopatologia , Estudos Prospectivos , Fatores de Risco , Privação do Sono/metabolismo , Privação do Sono/fisiopatologia , Fatores de Tempo , Estados Unidos/epidemiologia
16.
Osteoporos Int ; 24(1): 111-9, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22461074

RESUMO

UNLABELLED: In this prospective cohort study, depressive symptoms were associated with higher rates of bone loss in older men. Poorer performance on physical function tests partly explained the association between depressive symptoms and bone loss, suggesting that efforts to increase exercise and improve physical performance in depressed men may be beneficial. INTRODUCTION: The aim of this study was to ascertain whether depressive symptoms are associated with increased rates of bone loss at the hip in older men. METHODS: A population-based prospective cohort study of 2,464 community-dwelling men, aged 68 and older, enrolled in the Osteoporosis in Men Sleep Ancillary Study had depressive symptoms assessed by the Geriatric Depression Scale (GDS). Subjects were categorized as depressed if GDS ≥6 at the initial examination. Bone mineral density (BMD) at the hip was measured using dual-energy X-ray absorptiometry at the initial and follow-up examination (average 3.4 years between exams). Use of antidepressant medications was assessed by interview and verified from medication containers at the two examinations. A computerized dictionary was used to categorize type of medication. RESULTS: In a base model adjusted for age, race/ethnicity, and clinic site, the mean total hip BMD decreased 0.70 %/year in 136 men with a GDS score of ≥6 compared to 0.39 %/year in 2,328 men with a GDS score of <6 (p = 0.001). Walking speed and timed chair stand partly explained the association between depressive symptoms and rates of bone loss. CONCLUSION: Depression, as defined by a score of 6 or greater on the Geriatric Depression Scale, is associated with an increased rate of bone loss at the hip in this cohort of older men. Adjustment for walking speed and timed chair stand attenuated the strength of the association, suggesting that differences in physical functioning do partially explain the observed association.


Assuntos
Depressão/complicações , Osteoporose/etiologia , Absorciometria de Fóton , Idoso , Idoso de 80 Anos ou mais , Antidepressivos/administração & dosagem , Densidade Óssea/fisiologia , Depressão/tratamento farmacológico , Depressão/epidemiologia , Depressão/fisiopatologia , Uso de Medicamentos/estatística & dados numéricos , Fêmur/fisiopatologia , Colo do Fêmur/fisiopatologia , Articulação do Quadril/fisiopatologia , Humanos , Masculino , Osteoporose/epidemiologia , Osteoporose/fisiopatologia , Aptidão Física/fisiologia , Aptidão Física/psicologia , Estudos Prospectivos , Escalas de Graduação Psiquiátrica , Fatores de Risco , Estados Unidos/epidemiologia
17.
Osteoporos Int ; 24(5): 1637-46, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-22996743

RESUMO

UNLABELLED: Our randomized controlled trial in prematurely menopausal breast cancer survivors showed that impact + resistance training prevented increases in percentage of body fat compared with controls and also improved BMD at the hip and prevented BMD loss at the spine among exercise-trained women who were menopausal for >1 year. INTRODUCTION: Cancer treatment-related menopause worsens bone health and body composition in breast cancer survivors (BCS). We investigated whether impact + resistance training could improve bone mineral density (BMD), reduce bone turnover, build muscle, and decrease fat mass in BCS with premature menopause. METHODS: We conducted a randomized controlled trial in 71 BCS (mean age, 46.5 years) within 5 years of treatment-related menopause. Women were randomly assigned to one of two groups: (1) impact + resistance training (prevent osteoporosis with impact + resistance (POWIR)) or (2) exercise placebo (FLEX) 3×/week for 1 year. Outcomes were hip and spine BMD (in grams per square centimeter) and body composition (percent body fat (%BF) and lean and fat mass (in kilograms)) by DXA and bone turnover markers (serum osteocalcin (in nanograms per milliliter) and urinary deoxypryrodinoline (in nanomoles per milliliter). RESULTS: There were no significant group × time interactions for bone outcomes when using an intent-to-treat approach on the full sample. In analyses restricted to BCS who were menopausal for ≥1 year, POWIR increased BMD at the hip and slowed BMD loss at the spine compared with FLEX (femoral neck-POWIR, 0.004 ± 0.093 g/cm(2) vs. FLEX, -0.010 ± 0.089 g/cm(2); p < 0.01; spine-POWIR, -0.003 ± 0.114 g/cm(2) vs. FLEX, -0.020 ± 0.110 g/cm(2); p = 0.03). POWIR prevented increases in %BF (POWIR, 0.01 % vs. FLEX, 1.3 %; p < 0.04). Women with attendance to POWIR at ≥64 % had better improvements in %BF than women attending less often (p < 0.03). CONCLUSION: Impact + resistance training may effectively combat bone loss and worsening body composition from premature menopause in BCS.


Assuntos
Densidade Óssea/fisiologia , Neoplasias da Mama/tratamento farmacológico , Terapia por Exercício/métodos , Menopausa Precoce/fisiologia , Osteoporose Pós-Menopausa/prevenção & controle , Adulto , Antineoplásicos/efeitos adversos , Composição Corporal/fisiologia , Neoplasias da Mama/fisiopatologia , Feminino , Colo do Fêmur/fisiopatologia , Humanos , Vértebras Lombares/fisiopatologia , Pessoa de Meia-Idade , Osteoporose Pós-Menopausa/etiologia , Osteoporose Pós-Menopausa/fisiopatologia , Cooperação do Paciente , Treinamento Resistido/métodos , Sobreviventes , Resultado do Tratamento
18.
Aust Vet J ; 101(8): 296-301, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37082941

RESUMO

A 6-month-old male neutered Domestic Shorthair cat was assessed for a 24-h history of anorexia, lethargy, depressed mentation, mild abdominal pain and persistent bradycardia. Abdominal ultrasound revealed marked thickening of the gastric wall, gastric distension, free abdominal fluid, distension and corrugation of the small intestine. Full-thickness histopathological biopsy of the gastric wall demonstrated intralesional chitinous structures whose morphology (size and presence of obvious barbs) supports these structures being urticating hairs (setae). A processionary caterpillar is considered most likely as these are the most common urticating caterpillars in Australia. This is the first case of suspected severe gastroenteritis associated with the ingestion of caterpillar setae fragments in a cat.


Assuntos
Doenças do Gato , Gastroenterite , Mariposas , Masculino , Gatos , Animais , Sensilas/anatomia & histologia , Mariposas/anatomia & histologia , Gastroenterite/veterinária , Austrália , Ingestão de Alimentos , Doenças do Gato/diagnóstico por imagem , Doenças do Gato/etiologia
19.
Clin Oncol (R Coll Radiol) ; 35(6): e352-e361, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37031075

RESUMO

AIMS: Clinical equipoise exists regarding early-stage lung cancer treatment among patients as trials comparing stereotactic body radiation therapy (SBRT) and surgical resection are unavailable. Given the potential differences in treatment effectiveness and side-effects, we sought to determine the associations between treatment type, decision regret and depression. MATERIALS AND METHODS: A multicentre, prospective study of patients with stage IA-IIA non-small cell lung cancer (NSCLC) with planned treatment with SBRT or surgical resection was conducted. Decision regret and depression were measured using the Decision Regret Scale (DRS) and Patient Health Questionnaire-4 (PHQ-4) at 3, 6 and 12 months post-treatment, respectively. Mixed linear regression modelling examined associations between treatment and decision regret adjusting for patient sociodemographics. RESULTS: Among 211 study participants with early-stage lung cancer, 128 (61%) patients received SBRT and 83 (39%) received surgical resection. The mean age was 73 years (standard deviation = 8); 57% were female; 79% were White non-Hispanic. In the entire cohort at 3 months post-treatment, 72 (34%) and 57 (27%) patients had mild and severe decision regret, respectively. Among patients who received SBRT or surgery, 71% and 46% of patients experienced at least mild decision regret at 3 months, respectively. DRS scores increased at 6 months and decreased slightly at 12 months of follow-up in both groups. Higher DRS scores were associated with SBRT treatment (adjusted mean difference = 4.18, 95% confidence interval 0.82 to 7.54) and depression (adjusted mean difference = 3.49, 95% confidence interval 0.52 to 6.47). Neither patient satisfaction with their provider nor decision-making role concordance was associated with DRS scores. CONCLUSIONS: Most early-stage lung cancer patients experienced at least mild decision regret, which was associated with SBRT treatment and depression symptoms. Findings suggest patients with early-stage lung cancer may not be receiving optimal treatment decision-making support. Therefore, opportunities for improved patient-clinician communication probably exist.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Radiocirurgia , Humanos , Feminino , Idoso , Masculino , Carcinoma Pulmonar de Células não Pequenas/radioterapia , Carcinoma Pulmonar de Células não Pequenas/cirurgia , Carcinoma Pulmonar de Células não Pequenas/patologia , Neoplasias Pulmonares/radioterapia , Neoplasias Pulmonares/cirurgia , Neoplasias Pulmonares/patologia , Estudos Prospectivos , Resultado do Tratamento , Radiocirurgia/efeitos adversos , Emoções , Estadiamento de Neoplasias
20.
Br J Dermatol ; 167(2): 440-2, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22835024

RESUMO

Olmsted syndrome (OS) is a rare genodermatosis that is often difficult to diagnose because of clinical overlap with other disorders and its uncertain mode of inheritance. The molecular basis of OS was investigated in an Indian boy using comparative exome sequencing and Sanger sequencing data. Sequencing identified a G-to-A transition at position c.573 in the TRPV3 gene, producing the missense mutation p.Gly573Ser in the proband. This mutation was not identified in the mother. This study supports the recent finding of TRPV3 as the gene implicated in OS and suggests that the mutation p.Gly573Ser may be a recurrent abnormality in this genodermatosis.


Assuntos
Heterozigoto , Ceratodermia Palmar e Plantar/genética , Mutação de Sentido Incorreto/genética , Canais de Cátion TRPV/genética , Criança , Humanos , Masculino , Linhagem , Recidiva , Síndrome
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