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1.
Med Educ Online ; 28(1): 2241182, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37519051

RESUMO

Undergraduate medical learners from historically marginalized groups face significant barriers, which was made concrete at our institution when a student presented her research indicating that Black students felt unsure about which faculty members to approach. To better support our students, we used Kern's model for curriculum development and a critical pedagogy approach to create a Faculty Allyship Curriculum (FAC). A total of 790 individuals attended 90 workshops across 16 months and 20 individuals have completed the FAC. A majority of participants reported they felt at least moderately confident in their ability to teach learners who are underrepresented in medicine, mentor learners who are different than they are, and teach allyship topics. An informal content analysis of open-ended responses indicated changes in awareness, attitude, insight, and use of language and being more likely to display advocacy. For others considering creating a similar program, partnering with an existing program allows for rapid implementation and reach to a wide audience. We also recommend: beginning with a coalition of willing learners to quickly build community and culture change; ensuring that the curriculum supports ongoing personal commitment and change for the learners; and supporting facilitators in modeling imperfection and upstanding, 'calling in' rather than 'calling out' learners.


Assuntos
Currículo , Diversidade, Equidade, Inclusão , Docentes de Medicina , Estudantes , Humanos , Mentores , Estudantes/psicologia
2.
Adv Nutr ; 14(5): 948-958, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37270030

RESUMO

Achieving optimal health is an aspirational goal for the population, yet the definition of health remains unclear. The role of nutrition in health has evolved beyond correcting malnutrition and specific deficiencies and has begun to focus more on achieving and maintaining 'optimal' health through nutrition. As such, the Council for Responsible Nutrition held its October 2022 Science in Session conference to advance this concept. Here, we summarize and discuss the findings of their Optimizing Health through Nutrition - Opportunities and Challenges workshop, including several gaps that need to be addressed to advance progress in the field. Defining and evaluating various indices of optimal health will require overcoming these key gaps. For example, there is a strong need to develop better biomarkers of nutrient status, including more accurate markers of food intake, as well as biomarkers of optimal health that account for maintaining resilience-the ability to recover from or respond to stressors without loss to physical and cognitive performance. In addition, there is a need to identify factors that drive individualized responses to nutrition, including genotype, metabotypes, and the gut microbiome, and to realize the opportunity of precision nutrition for optimal health. This review outlines hallmarks of resilience, provides current examples of nutritional factors to optimize cognitive and performance resilience, and gives an overview of various genetic, metabolic, and microbiome determinants of individualized responses.


Assuntos
Microbioma Gastrointestinal , Ciências da Nutrição , Humanos , Estado Nutricional , Biomarcadores
3.
J Nutr Educ Behav ; 55(5): 331-342, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-37164549

RESUMO

OBJECTIVE: Identify factors influencing eating behaviors among emerging adults in the military. DESIGN: Focused ethnography using interviews, observations, and artifacts for data. SETTING: Three US Naval installations. PARTICIPANTS: Thirty-two active-duty Sailors aged 18-25 years. ANALYSIS: Qualitative data were organized in NVivo and analyzed sequentially to categorize culturally relevant domains and themes using a social ecological model (SEM). Descriptive statistics were used to describe questionnaire data in SPSS (version 27.0, IBM, 2020). RESULTS: Leaders encouraged healthy eating through policies and messages, but cultural contradictions and environmental barriers undermined Sailors' efforts to eat healthily. Stress and resource constraints (intrapersonal), peer pressure (social), unhealthy food environments and lack of access to food preparation (environmental), and eating on the go because of mission-first norms (cultural) promoted unhealthy eating behaviors. Nutrition and culinary literacy (intrapersonal); peer support and leadership engagement (social); access to healthy, convenient, and low-cost foods (environmental); and indoctrination to healthy eating during recruit training (cultural) positively influenced eating behaviors. CONCLUSION AND IMPLICATIONS: The eating behaviors of service members are influenced by many modifiable factors. Targeted education, leadership engagement, and policies that make nutritious foods easily accessible, appealing, and preferred are needed.


Assuntos
Militares , Humanos , Adulto , Adolescente , Adulto Jovem , Comportamento Alimentar , Estado Nutricional , Dieta Saudável
4.
Nutrients ; 15(5)2023 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-36904203

RESUMO

Optimal nutrition is imperative for psychological health. Oxidative stress and inflammation are underlying etiologies for alterations in psychological health. Warfighters are at risk of health concerns such as depression due to increased stress in austere environments and family separation while deployed. Over the last decade, research has demonstrated the health benefits of flavonoids found in fruits and berries. Berry flavonoids have potent antioxidant and anti-inflammatory properties by inhibiting oxidative stress and inflammation. In this review, the promising effects of various berries rich in bioactive flavonoids are examined. By inhibiting oxidative stress, berry flavonoids have the potential to modulate brain, cardiovascular, and intestinal health. There is a critical need for targeted interventions to address psychological health concerns within the warfighter population, and a berry flavonoid-rich diet and/or berry flavonoid dietary supplement intervention may prove beneficial as an adjunctive therapy. Structured searches of the literature were performed in the PubMed, CINAHL, and EMBASE databases using predetermined keywords. This review focuses on berry flavonoids' critical and fundamental bioactive properties and their potential effects on psychological health in investigations utilizing cell, animal, and human model systems.


Assuntos
Dieta , Flavonoides , Animais , Humanos , Flavonoides/farmacologia , Frutas , Antioxidantes/farmacologia , Inflamação
5.
J Spec Oper Med ; 23(1): 88-91, 2023 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-36827684

RESUMO

Full-spectrum Human Performance Optimization (HPO) is essential for Special Operations Forces (SOF). Adequate hydration is essential to all aspects of performance (physical and cognitive) and recovery. Water losses occur as a result of physical activity and can increase further depending on clothing and environmental conditions. Without intentional and appropriate strategic hydration planning, Operators are at increased risk for degradation in performance and exertional heat illness. The purpose of this article is to highlight current best practices for maintaining hydration before, during, and after activity, while considering various environmental conditions. Effective leadership and planning are necessary for preparing Operators for successful military operations.


Assuntos
Militares , Humanos , Militares/psicologia , Exercício Físico , Liderança
6.
BMJ Mil Health ; 2023 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-36792226

RESUMO

The role of nutrition and performance is well established. Service members' physical and cognitive performance, sleep and mood are impacted by nutritional choices. Although many eating patterns have emerged, consensus among experts recommend a dietary pattern focused on predominantly whole plant-based foods. Adequate intakes of fruits, vegetables, whole grains, beans, legumes, nuts and seeds should be prioritised. Implementation of strategic and intentional fuelling strategies around times of activity maintain adequate energy stores, enhance recovery and protect against training injuries. Carbohydrates are prioritised before, during and after activity or a mission, although the type and amount will vary based on duration and intensity of activity. Protein is generally the focus after activity or a mission and may be included before activity depending on individual tolerance. There are no specific recommendations for fat consumption before, during and after exercise that will improve performance. That said, Service members generally tolerate low-fat meals/snacks prior to exercise, limit fat intake during exercise, may include fat as part of the post exercise meal/snack, and generally consume most fat during the maintenance and growth phase. Careful consideration and planning for food and fluid requirements should be made when Service members are exposed to heat, cold and/or altitude. Operational rations are formulated to meet the nutritional needs of all Service members across a variety of diverse climates, environments and altitudes. Service members may use dietary supplements to improve their performance and need to be aware of available resources to help them make informed decisions.

7.
Neuroimage Clin ; 37: 103328, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36696808

RESUMO

BACKGROUND: Aging and dementia involve the disruption of brain molecular pathways leading to the alterations in tissue composition and gross morphology of the brain. Phenotypic and biomarker overlap between various etiologies of dementia supports a need for new modes of information to more accurately distinguish these disorders. Brain mechanical properties, which can be measured noninvasively by MR elastography, represent one understudied feature that are sensitive to neurodegenerative processes. In this study, we used two stiffness estimation schemes to test the hypothesis that different etiologies of dementia are associated with unique patterns of mechanical alterations across the cerebral cortex. METHODS: MR elastography data were acquired for six clinical groups including amyloid-negative cognitively unimpaired (CU), amyloid-positive cognitively unimpaired (A + CU), amyloid-positive participants with mild cognitive impairment (A + MCI), amyloid-positive participants with Alzheimer's clinical syndrome (A + ACS), dementia with Lewy bodies (DLB), and frontotemporal dementia (FTD). Stiffness maps were computed using two neural network inversions with the objective to at least partially separate the parenchyma-specific and morphological effects of neurodegeneration on mechanical property estimates. A tissue-confined inversion algorithm was designed to obtain the best estimate of stiffness in the brain parenchyma itself, while a regionally-aware inversion algorithm was used to measure the tissue stiffness along with the surroundings. Mean stiffness of 15 bilateral gray matter cortical regions were considered for statistical analysis. First, we tested the hypothesis that cortical stiffness changes in the aging brain. Next, we tested the overall study hypothesis by first comparing stiffness in each clinical group to the CU group, and then comparing the clinical groups against one another. Finally, we assessed the spatial and statistical overlap between atrophy and stiffness changes for both inversions. RESULTS: Cortical brain regions become softer with age for both inversions with larger effects observed using regionally-aware stiffness. Stiffness decreases in the range 0.010-0.027 kPa per year were observed. Pairwise comparisons of each clinical group with cognitively unimpaired participants demonstrated 5 statistically significant differences in stiffness for tissue-confined measurements and 19 statistically different stiffness changes for the regionally-aware stiffness measurements. Pairwise comparisons between clinical groups further demonstrated unique patterns of stiffness differences. Analysis of the atrophy-versus-stiffness relationship showed that regionally-aware stiffness measurements exhibit higher sensitivity to neurodegeneration with findings that are not fully explained by partial volume effects or atrophy. CONCLUSIONS: Both tissue-confined and regionally-aware stiffness estimates exhibited unique and complementary stiffness differences in various etiologies of dementia. Our results suggest that mechanical alterations measured by MRE reflect both tissue-specific differences as well as environmental effects. Multi-inversion schemes in MRE may provide new insights into the relationships between neuropathology and brain biomechanics.


Assuntos
Doença de Alzheimer , Técnicas de Imagem por Elasticidade , Demência Frontotemporal , Humanos , Técnicas de Imagem por Elasticidade/métodos , Demência Frontotemporal/patologia , Córtex Cerebral/patologia , Atrofia/patologia , Doença de Alzheimer/diagnóstico por imagem , Doença de Alzheimer/patologia , Imageamento por Ressonância Magnética/métodos
8.
Molecules ; 27(9)2022 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-35566133

RESUMO

Oxidative stress is a key underlying factor in cognitive decline and atherosclerosis. Oxidative stress occurs at the cellular level with an imbalance between reactive oxygen species and reactive nitrogen species and a deficiency in antioxidants. Mounting evidence suggests that berry flavonoids may promote cellular health by exerting antioxidant properties. Black currant and various berry extracts were tested in microglia (BV-2) and cardiomyocyte (HL-1) cell lines to study their biological effects. The principal ingredients in black currant and cranberry extract-delphinidin 3-rutinoside (D3R) and cyanidin 3-glucoside (C3G), were also assessed. A menadione-induced oxidative stressor was used, and its output was quantified to detect oxidative stress (CellROXTM). Black currant extract had similar antioxidant effects as N-acetylcysteine (NAC) in HL-1 cells with regard to cellular protection, whereas cranberry extract was ineffective. In contrast, cranberry extract was comparable in effectiveness to black currant extract in BV-2 cells. D3R and C3G also reduced oxidative stress similarly to whole berry extracts, which indicates that these ingredients may confer the antioxidant effects of berries. Black currant and cranberry extracts inhibit oxidative stress in microglial and cardiomyocyte cell lines. Black currant extract was more effective in reducing oxidative stress in the HL-1 cells, whereas cranberry extract was comparable in reducing oxidative stress in the BV-2 cells. The results suggest that berry flavonoids exert neuro- and cardioprotective effects.


Assuntos
Ribes , Vaccinium macrocarpon , Antocianinas/farmacologia , Antioxidantes/farmacologia , Frutas , Microglia , Miócitos Cardíacos , Estresse Oxidativo , Extratos Vegetais/farmacologia
9.
Magn Reson Med ; 88(2): 916-929, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35381121

RESUMO

PURPOSE: Inversion algorithms used to convert acquired MR elastography wave data into material property estimates often assume that the underlying materials are locally homogeneous. Here we evaluate the impact of that assumption on stiffness estimates in gray-matter regions of interest in brain MR elastography. METHODS: We describe an updated neural network inversion framework using finite-difference model-derived data to train convolutional neural network inversion algorithms. Neural network inversions trained on homogeneous simulations (homogeneous learned inversions [HLIs]) or inhomogeneous simulations (inhomogeneous learned inversions [ILIs]) are generated with a variety of kernel sizes. These inversions are evaluated in a brain MR elastography simulation experiment and in vivo in a test-retest repeatability experiment including 10 healthy volunteers. RESULTS: In simulation and in vivo, HLI and ILI with small kernels produce similar results. As kernel size increases, the assumption of homogeneity has a larger effect, and HLI and ILI stiffness estimates show larger differences. At each inversion's optimal kernel size in simulation (7 × 7 × 7 for HLI, 11 × 11 × 11 for ILI), ILI is more sensitive to true changes in stiffness in gray-matter regions of interest in simulation. In vivo, there is no difference in the region-level repeatability of stiffness estimates between the inversions, although ILI appears to better maintain the stiffness map structure as kernel size increases, while decreasing the spatial variance in stiffness estimates. CONCLUSIONS: This study suggests that inhomogeneous inversions provide small but significant benefits even when large stiffness gradients are absent.


Assuntos
Técnicas de Imagem por Elasticidade , Algoritmos , Encéfalo/diagnóstico por imagem , Técnicas de Imagem por Elasticidade/métodos , Substância Cinzenta , Humanos , Imageamento por Ressonância Magnética/métodos , Redes Neurais de Computação
10.
Br J Nutr ; 128(8): 1518-1525, 2022 10 28.
Artigo em Inglês | MEDLINE | ID: mdl-34758890

RESUMO

In the USA, as many as 20 % of recruits sustain stress fractures during basic training. In addition, approximately one-third of female recruits develop Fe deficiency upon completion of training. Fe is a cofactor in bone collagen formation and vitamin D activation, thus we hypothesised Fe deficiency may be contributing to altered bone microarchitecture and mechanics during 12-weeks of increased mechanical loading. Three-week old female Sprague Dawley rats were assigned to one of four groups: Fe-adequate sedentary, Fe-deficient sedentary, Fe-adequate exercise and Fe-deficient exercise. Exercise consisted of high-intensity treadmill running (54 min 3×/week). After 12-weeks, serum bone turnover markers, femoral geometry and microarchitecture, mechanical properties and fracture toughness and tibiae mineral composition and morphometry were measured. Fe deficiency increased the bone resorption markers C-terminal telopeptide type I collagen and tartate-resistant acid phosphatase 5b (TRAcP 5b). In exercised rats, Fe deficiency further increased bone TRAcP 5b, while in Fe-adequate rats, exercise increased the bone formation marker procollagen type I N-terminal propeptide. In the femur, exercise increased cortical thickness and maximum load. In the tibia, Fe deficiency increased the rate of bone formation, mineral apposition and Zn content. These data show that the femur and tibia structure and mechanical properties are not negatively impacted by Fe deficiency despite a decrease in tibiae Fe content and increase in serum bone resorption markers during 12-weeks of high-intensity running in young growing female rats.


Assuntos
Reabsorção Óssea , Deficiências de Ferro , Corrida , Ratos , Feminino , Animais , Tíbia , Fosfatase Ácida Resistente a Tartarato , Densidade Óssea , Ratos Sprague-Dawley , Fêmur
11.
J Spec Oper Med ; 21(2): 92-97, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34105130

RESUMO

Nutritional fitness is a key goal of every Special Operations Forces (SOF) Operator, and nutrition is one way of potentially gaining a necessary edge. Although fad diets are popular among SOF Operators, many have no evidence with regard to military-specific tasks. One fad diet-intermittent fasting (IF)-is clearly the rage across the United States (US) and popular as a dietary pattern. Most fad diets are studied in the context of various chronic diseases, in particular, cardiovascular disease, diabetes, and obesity, and there are no data on the benefits among SOF or any military population. Thus, evidence demonstrating improvements in performance is typically lacking. Despite no clear evidence, many still devote their lives to popular fad diets. We address whether IF confers performance improvements in SOF by first discussing the concepts of metabolic flexibility and metabolic shifting, then describing IF and its subtypes, after which we summarize the literature with regard to cardiovascular disease and obesity. We close with how IF impacts performance and discuss who should use consider using IF as a dietary pattern.


Assuntos
Jejum , Militares , Dieta , Exercício Físico , Humanos , Estado Nutricional , Obesidade , Estados Unidos
12.
Med Image Anal ; 63: 101710, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32442867

RESUMO

PURPOSE: To test the hypothesis that removing the assumption of material homogeneity will improve the spatial accuracy of stiffness estimates made by Magnetic Resonance Elastography (MRE). METHODS: An artificial neural network was trained using synthetic wave data computed using a coupled harmonic oscillator model. Material properties were allowed to vary in a piecewise smooth pattern. This neural network inversion (Inhomogeneous Learned Inversion (ILI)) was compared against a previous homogeneous neural network inversion (Homogeneous Learned Inversion (HLI)) and conventional direct inversion (DI) in simulation, phantom, and in-vivo experiments. RESULTS: In simulation experiments, ILI was more accurate than HLI and DI in predicting the stiffness of an inclusion in noise-free, low-noise, and high-noise data. In the phantom experiment, ILI delineated inclusions ≤ 2.25 cm in diameter more clearly than HLI and DI, and provided a higher contrast-to-noise ratio for all inclusions. In a series of stiff brain tumors, ILI shows sharper stiffness transitions at the edges of tumors than the other inversions evaluated. CONCLUSION: ILI is an artificial neural network based framework for MRE inversion that does not assume homogeneity in material stiffness. Preliminary results suggest that it provides more accurate stiffness estimates and better contrast in small inclusions and at large stiffness gradients than existing algorithms that assume local homogeneity. These results support the need for continued exploration of learning-based approaches to MRE inversion, particularly for applications where high resolution is required.


Assuntos
Técnicas de Imagem por Elasticidade , Algoritmos , Simulação por Computador , Humanos , Imageamento por Ressonância Magnética , Redes Neurais de Computação , Imagens de Fantasmas
13.
J Acad Nutr Diet ; 120(9): 1469-1483, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32273242

RESUMO

BACKGROUND: Health trends, which promote performance enhancement and maintaining or increasing muscle strength, may appeal to soldiers looking to maintain health standards set by the US Army, but often these trends require further investigation to assess safety and efficacy. High-intensity interval training (HIIT) and use of weight loss and/or performance-enhancing/body-building dietary supplements (WL/PES DS) are two such trends that, if implemented inappropriately, can negatively impact soldier health and readiness. OBJECTIVE: Our aim was to establish health/psychosocial profiles of US Army soldiers who participate in HIIT and/or use WL/PES DS. DESIGN: This cross-sectional observational study used data from the 2016 US Army Global Assessment Tool. PARTICIPANTS: Data were analyzed from respondents to the 2016 US Army Global Assessment Tool (n=299,996) who consented to have their data used for research purposes. RESULTS: Soldiers were classified into four groups based on HIIT and/or WL/PES DS use. Thirty-five percent of soldiers participated in HIIT and 10% took WL/PES DS at least once per month in the last year. HIIT participation was associated with higher reported odds of healthy behaviors and higher emotional and social fitness. In contrast to HIIT, WL/PES DS use was associated with higher reported odds of risky behaviors (hazardous drinking and tobacco use) and lower psychosocial fitness. The group participating in HIIT but not using WL/PES DS reported fewer unhealthy behaviors compared to the HIIT+WL/PES DS and WL/PES DS-only groups. CONCLUSIONS: Engaging in HIIT is associated with higher reported odds of healthy behaviors and increased psychosocial fitness. However, soldiers who engaged in HIIT also have increased odds of WL/PES DS use, which is associated with greater reported risky behaviors and reduced fitness. Although HIIT and WL/PES DS use are related, they are associated with different reported health/risky behaviors and different psychosocial attributes.


Assuntos
Suplementos Nutricionais/estatística & dados numéricos , Comportamentos Relacionados com a Saúde , Treinamento Intervalado de Alta Intensidade/psicologia , Militares/psicologia , Substâncias para Melhoria do Desempenho/uso terapêutico , Adolescente , Adulto , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estados Unidos , Redução de Peso , Adulto Jovem
14.
Mil Med ; 184(9-10): 198, 2019 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-31318418
15.
Scand J Med Sci Sports ; 29(9): 1322-1330, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31099085

RESUMO

Vitamin D's role in regulating immune responses may increase during periods of elevated psychological and physiological stress. Due to the high demands placed on US Marine Corps recruits undergoing 12 weeks of basic military training, we hypothesized that vitamin D status would be related to markers of innate mucosal immunity, and daily vitamin D supplementation would augment immune responses during training. Males (n = 75) and females (n = 74) entering recruit basic training during the summer and winter volunteered to participate in a randomized, double-blind, placebo-controlled study. Subjects received either 1000 IU vitamin D3  + 2000 mg calcium/d (n = 73) or placebo (n = 76) for 12 weeks. Saliva samples were collected pre-training, during (weeks 4 and 8), and post-training (week 12) in order to determine salivary SIgA and cathelicidin (indices of mucosal immunity) and α-amylase (indicator of stress). Initial (baseline) and post-training serum 25(OH)D levels were measured. Results were as follows: serum 25(OH)D levels were 37% higher in recruits entering training in summer compared with winter. A positive relationship was observed between baseline 25(OH)D levels and SIgA secretion rates (-SR). When stress levels were high during summer training, baseline 25(OH)D levels contributed to an increase in salivary secretory immunoglobulin A secretion rates (SIgA-SR) and cathelicidin-SR, the latter only in males. Vitamin D supplementation contributed to the changes in SIgA-SR and cathelicidin-SR, specifically SIgA-SR was higher in the treatment group. These data highlight the importance of vitamin D and mucosal immune responses during arduous basic military training when stress levels are increased.


Assuntos
Colecalciferol/administração & dosagem , Suplementos Nutricionais , Imunidade nas Mucosas , Condicionamento Físico Humano , Saliva/imunologia , Estações do Ano , Adolescente , Peptídeos Catiônicos Antimicrobianos/análise , Cálcio/administração & dosagem , Método Duplo-Cego , Feminino , Humanos , Imunoglobulina A/análise , Masculino , Militares , Vitamina D/análogos & derivados , Vitamina D/sangue , Adulto Jovem , alfa-Amilases/análise , Catelicidinas
16.
Bone ; 123: 224-233, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30902791

RESUMO

Stress fractures are common overuse injuries caused by repetitive bone loading. These fractures are of particular concern for military recruits and athletes resulting in attrition in up to 60% of recruits that sustain a fracture. Army and Navy recruits supplemented with daily calcium and vitamin D (Ca + D) demonstrated improved bone strength and reduced stress fractures. The aim of the current study was to evaluate whether Ca + D supplementation improves measures of bone health in recruits undergoing United States Marine Corps initial military training (IMT), and whether the effect of supplementation on indices of bone health varied by season. One-hundred ninety-seven Marine recruits (n = 107 males, n = 90 females, mean age = 18.9 ±â€¯1.6 y) were randomized to receive either Ca + D fortified snack bars (2000 mg Ca and 1000 IU vitamin D per day) or placebo divided into twice daily doses during 12 weeks of IMT. Anthropometrics, fasted blood samples, and peripheral quantitative computed tomography (pQCT) scans of the tibial metaphysis and diaphysis were collected upon entrance to- and post-training (12 weeks later). Half of the volunteers entered training in July and the other half started in February. Time-by-group interactions were observed for vitamin D status (25OHD) and the bone turnover markers, BAP, TRAP and OCN. 25OHD increased and BAP, TRAP and OCN all decreased in the Ca + D group (p < .05). Training increased distal tibia volumetric BMD (+1.9 ±â€¯2.8%), BMC (+2.0 ±â€¯3.1%), and bone strength index (BSI; +4.0 ±â€¯4.0%) and diaphyseal BMC (+1.0 ±â€¯2.2%) and polar stress strain index (SSIp; +0.7 ±â€¯2.1%) independent of Ca + D supplementation (p < .05 for all). When analyzed by season, change in BSI was greater in the Ca + D group as compared to placebo in the summer iteration only (T*G; p < .05). No other effects of supplementation on bone tissue were observed. When categorized by tertile of percent change in BSI, recruits demonstrating the greatest changes in BSI and 25OHD entered training with the lowest levels of 25OHD (p < .05). Over all, these results suggest that Ca + D supplementation reduced some markers of bone formation and resorption and the decline in 25OHD over training in volunteers that started training in the summer was prevented by supplementation. Baseline 25OHD and trajectory may impact bone responses to IMT, but little effect of Ca + D supplementation was observed at the investigated doses.


Assuntos
Densidade Óssea/efeitos dos fármacos , Cálcio/administração & dosagem , Suplementos Nutricionais , Militares , Estações do Ano , Vitamina D/administração & dosagem , Adolescente , Adulto , Biomarcadores/sangue , Densidade Óssea/fisiologia , Cálcio/sangue , Cálcio da Dieta/administração & dosagem , Cálcio da Dieta/sangue , Método Duplo-Cego , Feminino , Humanos , Masculino , Condicionamento Físico Humano/métodos , Condicionamento Físico Humano/fisiologia , Vitamina D/sangue , Adulto Jovem
17.
Nutr Neurosci ; 22(1): 19-28, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28721750

RESUMO

BACKGROUND: Differences in the composition of control diets may confound outcomes in studies investigating dietary effects. OBJECTIVE: We compared the effects of two control diets commonly used in mice studies, chow (SD) and a purified low-fat diet (LFD), in relation to a chronic high-fat diet (HFD). We hypothesized that SD and LFD will have similar effects on phenotypic, metabolic, and behavioral outcomes. METHODS: Fifty-four 5-week-old male C57BL/6J mice were randomly assigned to one of the three dietary interventions (SD, LFD, or HFD) for 18 weeks. At week 16, mice were tested for behavioral changes. Glucose tolerance testing was conducted at week 17 and terminal blood collection at week 18. RESULTS: SD and LFD mice exhibited no differences in cognitive performance on the Y-maze test and comparable anxiety-like behavior in the open-field and elevated zero maze tests. Significant declines in cognitive function and greater anxiety-like behavior were observed in the HFD group compared to both SD and LFD. Areas under the glucose tolerance curve were similar for SD and LFD, as were levels of high-density lipoprotein, triglycerides, cytokines, and adipocytokines. Only total cholesterol was significantly higher in LFD mice compared to SD mice. All measures were significantly higher in the HFD group. DISCUSSION: Our data demonstrate that young mice develop similar phenotypic, metabolic, and behavioral profiles when fed SD vs. LFD. The two diets may thus be equally appropriate as controls for an HFD, although some studies may want to consider differences in effects on cholesterol levels.


Assuntos
Comportamento Animal , Dieta com Restrição de Gorduras , Dieta Hiperlipídica , Adipocinas/sangue , Animais , Ansiedade/sangue , Ansiedade/diagnóstico , Colesterol/sangue , Cognição , Citocinas/sangue , Dieta , Modelos Animais de Doenças , Teste de Tolerância a Glucose , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Triglicerídeos/sangue , Aumento de Peso
19.
Nutr Today ; 53(5): 229-233, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30774152

RESUMO

Over half of young adults, athletes, and Military Service Members self-report using at least one dietary supplement (DS) 1 or more times per week. DS may be consumed to improve health, provide more energy, increase muscle strength, and/or enhance performance. The United States Food and Drug Administration (FDA) has raised concerns regarding adulteration, safety, and adverse events associated with DS marketed for brain health and bodybuilding. Some DS products may compromise health as well as lead to a serious adverse event. The National Institutes of Health (NIH) Dietary Supplement Label Database (DSLD), available at https://dsld.nlm.nih.gov/, can be freely accessed and used by researchers, providers, and consumers alike to screen for potentially harmful DS. It was developed to serve the research community and as a resource for health care providers and the public. Herein we provide two examples of how the database can be used to identify DS ingredients of concern in products marketed for brain health and bodybuilding. The search for DS marketed for brain health returned 49 unique DS, and the search on DS marketed for bodybuilding returned 18 unique DS. Search results were cross-referenced with the Operation Supplement Safety High-Risk Supplement List, the FDA Tainted Products Marketed as Dietary Supplements list, the Natural Medicines database, and NIH Office of Dietary Supplements Fact Sheets. Three ingredients found in DS marketed for brain health and two ingredients in DS marketed for bodybuilding were identified as "of concern". Educational tools, including the DSLD, can help consumers and providers make informed decisions regarding DS.

20.
Mil Med ; 182(11): e2086-e2091, 2017 11.
Artigo em Inglês | MEDLINE | ID: mdl-29087887

RESUMO

BACKGROUND: The use of dietary supplements (DSs) is widespread in the military. Service members use DS for any number of reasons, to include supporting general health, increasing energy levels, enhancing performance, and promoting gains in strength. However, some readily available DS products are potentially unsafe. Therefore, the purpose of this study is to assess the ability of military medical students to use the Operation Supplement Safety DS risk assessment tool. The Operation Supplement Safety risk assessment tool was developed to assist Service members in making decisions about safe DS use. METHODS: Fourth-year medical students used an online assessment tool to risk stratify and evaluate the safety of 12 predesignated DS. The assessment tool consists of seven polar questions (yes/no), with an answer of "yes" given a score of 1 and an answer of "no" given a score of 0. Students recorded responses to each of the seven questions for each of the 12 DSs. The tool then generated a total score for each DS, which was compared to the previously identified correct total score. Students' scores for each individual yes/no question and final conclusion about DS safety were also assessed. FINDINGS: Forty responses for the 12 DSs were examined. Five supplements were expected to receive a score of ≥4, suggesting they were likely safe. The average scores (± standard deviation [SD]) for each DS vs. the correct safety score were fish oil (5.9 ± 1.4 vs. 7.0), iron (4.2 ± 1.4 vs. 4.0), melatonin (4.9 ± 0.8 vs. 5.0), multivitamin/mineral (3.8 ± 1.1 vs. 4.0), multivitamin/mineral for men (4.0 ± 1.0 vs. 5.0), performance-enhancing supplement A (1.5 ± 1.1 vs. 2.0), performance-enhancing supplement B (2.0 ± 1.0 vs. 3.0), performance-enhancing supplement C (0.6 ± 0.5 vs. 1.0), performance-enhancing supplement D (1.8 ± 1.0 vs. 3.0), performance-enhancing supplement E (1.5 ± 1.3 vs. 1.0), sexual enhancement supplement (1.3 ± 0.7 vs. 1.0), and weight loss supplement (1.1 ± 1.1 vs. 1.0). DISCUSSION/IMPACT/RECOMMENDATIONS: The DS risk assessment tool provides consumers a quick way to screen DS for safety and can help consumers make more informed decisions when purchasing DS. Scores had minimal intersubject variability and were comparable to expected risk stratification. Our results suggest the assessment tool may be appropriate for medical students to use when investigating the safety of DS. We recommend additional research to verify whether the findings from this study would be similar for other potential users, as well as assess other psychometric properties.


Assuntos
Suplementos Nutricionais/normas , Medição de Risco/métodos , Adulto , Suplementos Nutricionais/estatística & dados numéricos , Feminino , Humanos , Masculino , Inquéritos e Questionários
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