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1.
J Strength Cond Res ; 2024 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-38857438

RESUMO

ABSTRACT: Buga, A, Decker, DD, Robinson, BT, Crabtree, CD, Stoner, JT, Arce, LF, El-Shazly, X, Kackley, ML, Sapper, TN, Anders, JPV, Kraemer, WJ, and Volek, JS. The VirTra V-100 is a test-retest reliable shooting simulator for measuring accuracy/precision, decision-making, and reaction time in civilians, police/SWAT, and military personnel. J Strength Cond Res XX(X): 000-000, 2024-Law-enforcement agencies and the military have increasingly used virtual reality (VR) to augment job readiness. However, whether VR technology captures consistent data for shooting performance evaluation has never been explored. We enrolled 30 adults (24 M/6 F) to examine test-retest reliability of the VirTra shooting simulator. Approximately 30% of the sample had a tactical background (PD/SWAT and military). Trained research staff familiarized subjects with how to shoot the infrared-guided M4 rifle at digitally projected targets. Subjects then performed 3 identical experimental shooting sessions (consecutive or separated by 1-2 days) that assessed accuracy/precision, decision-making, and reaction time. Key metrics comprised projectile Cartesian position ( x , y ), score, time, and throughput (score or accuracy divided by time). Test-retest reliability was measured with intraclass correlation coefficients (ICC). After each visit, subjects completed a perceptual survey to self-evaluate their shooting performance and perceived VR realism. The simulator captured 21 ballistic variables with good to excellent test-retest agreement, producing a global ICC of 0.78. Notable metrics were the individual projectile distances to the center of the target (0.81), shot group radius (0.91), time-to-first decision (0.97), decision-making throughput (0.95), and target transition reaction time (0.91). Subjects had positive self-evaluations about their shooting performance, with "confidence" increasing from baseline to the end of the study ( p = 0.014). The VirTra V-100 virtual ballistic shooting simulator captures data with a high degree of test-retest reliability and is easy to familiarize regardless of starting expertise levels, making it appropriate for use as a method to objectively track progress or a tactical research testing tool.

2.
Magn Reson Med ; 2024 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-38733066

RESUMO

PURPOSE: To present and assess an outlier mitigation method that makes free-running volumetric cardiovascular MRI (CMR) more robust to motion. METHODS: The proposed method, called compressive recovery with outlier rejection (CORe), models outliers in the measured data as an additive auxiliary variable. We enforce MR physics-guided group sparsity on the auxiliary variable, and jointly estimate it along with the image using an iterative algorithm. For evaluation, CORe is first compared to traditional compressed sensing (CS), robust regression (RR), and an existing outlier rejection method using two simulation studies. Then, CORe is compared to CS using seven three-dimensional (3D) cine, 12 rest four-dimensional (4D) flow, and eight stress 4D flow imaging datasets. RESULTS: Our simulation studies show that CORe outperforms CS, RR, and the existing outlier rejection method in terms of normalized mean square error and structural similarity index across 55 different realizations. The expert reader evaluation of 3D cine images demonstrates that CORe is more effective in suppressing artifacts while maintaining or improving image sharpness. Finally, 4D flow images show that CORe yields more reliable and consistent flow measurements, especially in the presence of involuntary subject motion or exercise stress. CONCLUSION: An outlier rejection method is presented and tested using simulated and measured data. This method can help suppress motion artifacts in a wide range of free-running CMR applications.

3.
Int J Cardiovasc Imaging ; 40(5): 1081-1094, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38625629

RESUMO

This study sought to evaluate the impact of severe obesity on image quality and ventricular function assessment in cardiovascular magnetic resonance (MRI) and trans-thoracic echocardiography (TTE). We studied 100 consecutive patients who underwent clinically indicated cardiac MRI and TTE studies within 12 months between July 2017 and December 2020; 50 (28 females and 22 males; 54.5 ± 18.7 years) with normal body mass index (BMI) (18.5-25 kg/m2) and 50 (21 females and 29 males; 47.2 ± 13.3 years) with severe obesity (BMI ≥ 40 kg/m2). MRI and TTE image quality scores were compared within and across cohorts using a linear mixed model. Categorical left (LVF) and right (RVF) ventricular function were compared using Cohens Kappa statistic. Mean BMI for normal weight and obese cohorts were 22.2 ± 1.7 kg/m2 and 50.3 ± 5.9 kg/m2, respectively. Out of a possible 93 points, mean MRI image quality score was 91.5 ± 2.5 for patients with normal BMI, and 88.4 ± 5.5 for patients with severe obesity; least square (LS) mean difference 3.1, p = 0.460. TTE scores were 64.2 ± 13.6 for patients with normal BMI and 46.0 ± 12.9 for patients with severe obesity, LS mean difference 18.2, p < 0.001. Ventricular function agreement between modalities was worse in the obese cohort for both LVF (72% vs 80% agreement; kappa 0.53 vs 0.70, obese vs. normal BMI), and RVF (58% vs 72% agreement, kappa 0.18 vs 0.34, obese vs. normal BMI). Severe obesity had limited impact on cardiac MRI image quality, while obesity significantly degraded TTE image quality and ventricular function agreement with MRI.


Assuntos
Índice de Massa Corporal , Ecocardiografia , Obesidade Mórbida , Valor Preditivo dos Testes , Função Ventricular Esquerda , Função Ventricular Direita , Humanos , Feminino , Masculino , Pessoa de Meia-Idade , Adulto , Idoso , Obesidade Mórbida/complicações , Obesidade Mórbida/diagnóstico por imagem , Obesidade Mórbida/fisiopatologia , Reprodutibilidade dos Testes , Estudos Retrospectivos , Imageamento por Ressonância Magnética , Imagem Cinética por Ressonância Magnética
4.
Opt Lett ; 49(6): 1473-1476, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38489428

RESUMO

The electronic excitation of key combustion species or flow tagging of chemical species requires a narrowband tunable UV source. In this work, a potassium titanyl phosphate (KTP) burst-mode optical parametric oscillator (OPO) pumped by a 532 nm laser is developed to generate a spectrally narrow signal and an idler output with 1.48 ± 0.19 cm-1 bandwidth without the need for injection seeding. The idler (1410-1550 nm range) is further mixed with 355 or 266 nm to generate 284 or 226 nm for OH or NO planar laser-induced fluorescence (PLIF), respectively, with up to 1.9% conversion efficiency from 1064 nm to the UV. MHz-rate burst profiles are reported, and OH and NO PLIF are demonstrated in a rotating detonation combustor at rates up to 200 kHz.

5.
PLoS One ; 19(1): e0296523, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38166036

RESUMO

PURPOSE: Ketogenic diets may positively influence cancer through pleiotropic mechanisms, but only a few small and short-term studies have addressed feasibility and efficacy in cancer patients. The primary goals of this study were to evaluate the feasibility and the sustained metabolic effects of a personalized well-formulated ketogenic diet (WFKD) designed to achieve consistent blood beta-hydroxybutyrate (ßHB) >0.5 mM in women diagnosed with stage IV metastatic breast cancer (MBC) undergoing chemotherapy. METHODS: Women (n = 20) were enrolled in a six month, two-phase, single-arm WFKD intervention (NCT03535701). Phase I was a highly-supervised, ad libitum, personalized WFKD, where women were provided with ketogenic-appropriate food daily for three months. Phase II transitioned women to a self-administered WFKD with ongoing coaching for an additional three months. Fasting capillary ßHB and glucose were collected daily; weight, body composition, plasma insulin, and insulin resistance were collected at baseline, three and six months. RESULTS: Capillary ßHB indicated women achieved nutritional ketosis (Phase I mean: 0.8 mM (n = 15); Phase II mean: 0.7 mM (n = 9)). Body weight decreased 10% after three months, primarily from body fat. Fasting plasma glucose, plasma insulin, and insulin resistance also decreased significantly after three months (p < 0.01), an effect that persisted at six months. CONCLUSIONS: Women diagnosed with MBC undergoing chemotherapy can safely achieve and maintain nutritional ketosis, while improving body composition and insulin resistance, out to six months.


Assuntos
Neoplasias da Mama , Dieta Cetogênica , Resistência à Insulina , Insulinas , Cetose , Humanos , Feminino , Neoplasias da Mama/tratamento farmacológico , Estudos de Viabilidade , Ácido 3-Hidroxibutírico
6.
Clin Nutr ESPEN ; 54: 277-287, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36963874

RESUMO

BACKGROUND: Single doses of exogenous ketone salts (KS) transiently increase circulating beta-hydroxybutyrate (BHB) (∼1 mM; 1-2 h) regardless of starting levels of ketosis; however, no studies have explored how sustained use of KS influences measures of ketonemia and glycemia. OBJECTIVES: To determine the response to a hypocaloric, well-formulated ketogenic diet (KD), with and without the inclusion of two daily racemic KS doses (6 g R-BHB + 6 g S-BHB per serving) on 1) daily fasting capillary R-BHB and glucose (R-BHB/GLUfast), 2) bi-weekly 13 h diurnal BHB and glucose (R-BHB/GLUdiur), 3) three-hours post-KS ingestion kinetics (R-BHBKS), and 4) bi-weekly fasting plasma enantiomer-specific BHB (R/S-BHBplasma). METHODS: Non-diabetic adults with overweight and obesity were randomized to receive a precisely measured hypocaloric KD (∼75 %en of maintenance) for six weeks, supplemented twice-daily with KS or placebo (PL). A non-randomized comparison group was provided an isonitrogenous/isoenergetic low-fat diet (LFD). All meals were provided to subjects. Capillary blood was collected daily to measure R-BHB/GLUfast and hourly for R-BHB/GLUdiur. Plasma was collected to measure R/S-BHBplasma, insulin, fasting glucose, and insulin resistance (HOMA-IR). Total AUC was calculated using the trapezoidal method. RESULTS: Mean R-BHBfast increased significantly during KD + PL (1.0 mM BHB), an effect enhanced 26% during KD + KS. GLUfast AUC was -6% lower during KD + KS versus LFD. Mean R-BHBdiur increased 40% in KD + KS versus KD + PL, whereas GLUdiur decreased 13% during both KDs versus LFD. R-BHBKS peaked (Δ: ∼1 mM) 1 h after the morning KS dose, but not following the afternoon dose. Both R/S-BHBplasma increased during KD independent of KS inclusion. R-BHBplasma was 50-times greater compared to S-BHBplasma, and the KS augmented S-BHBplasma 50% more than PL. Fasting insulin and HOMA-IR decreased after 14 days independent of diet. CONCLUSIONS: A hypocaloric KD was effective at reducing diurnal glucose compared to a LFD independent of weight loss, but twice-daily racemic KS ingestion during KD augmented ketonemia, both as R- and S-BHB, and decreased mean fasting glucose beyond a KD alone. The hypoglycemic effects of KD in combination with exogenous ketones merit further investigation.


Assuntos
Dieta Cetogênica , Cetose , Adulto , Humanos , Ácido 3-Hidroxibutírico , Sais , Corpos Cetônicos , Cetonas , Glucose , Insulina , Jejum
7.
J Clin Endocrinol Metab ; 108(7): 1727-1739, 2023 06 16.
Artigo em Inglês | MEDLINE | ID: mdl-36629058

RESUMO

CONTEXT: Ketogenic diets (KDs) and low-fat diets (LFD) result in similar weight loss, but have differential cardiometabolic effects on lipids and insulin. Generally, weight loss decreases renin-angiotensin-aldosterone system (RAAS) activity. OBJECTIVE: Investigate the effects of KDs with varying sodium content vs LFD on RAAS in overweight and obese adults. METHODS: Twenty-eight participants were randomized 1:1 to a KD + ketone salt supplement (KD + KS) or a KD + placebo (KD + PL) arm with prepared hypocaloric meals. Twelve participants were enrolled in a post hoc LFD arm. Serum renin, aldosterone, and anthropometric and metabolic biomarkers were assessed at 0, 2, 4, and 6 weeks. Linear mixed models with random intercepts were used to compare between group differences controlling for sex and body mass index. RESULTS: Participants had a median age of 33 years, 51% female, weighed 91.3 kg, with body mass index 30.6 kg/m2. At 6 weeks, weight decreased by 6, 8, and 7 kg on average in the KD + KS, KD + PL, and LFD groups, respectively (P < .05). Aldosterone increased by 88% and 144% in the KD + PL and KD + KS groups, respectively, but did not change in the LFD after 6 weeks while renin decreased across groups. Systolic and diastolic blood pressure did not change in the KD + PL and KD + KS groups. Log ketones were positively associated with aldosterone (P < .001). Aldosterone was not associated with cardiovascular measures including blood pressure and ejection fraction (P > .05). CONCLUSION: KD reduced weight and increased aldosterone without worsening cardiometabolic risk factors. Future KD studies are needed to elucidate mechanistic connections between ketones and aldosterone.


Assuntos
Dieta Cetogênica , Cetonas , Adulto , Humanos , Feminino , Masculino , Renina , Aldosterona , Dieta com Restrição de Gorduras , Corpos Cetônicos , Dieta Cetogênica/efeitos adversos , Redução de Peso/fisiologia
8.
J Am Nutr Assoc ; 42(2): 169-177, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35512774

RESUMO

BACKGROUND: Ketosis has been reported to benefit healthspan and resilience, which has driven considerable interest in development of exogenous ketones to induce ketosis without dietary changes. Bis hexanoyl (R)-1,3-butanediol (BH-BD) is a novel ketone di-ester that can be used as a food ingredient that increases hepatic ketogenesis and blood beta-hydroxybutyrate (BHB) concentrations. METHODS: Here, we provide the first description of blood ketone and metabolite kinetics for up to five hours after consumption of a beverage containing BH-BD by healthy adults (n = 8) at rest in three randomized, cross-over conditions (25 g + Meal (FEDH); 12.5 g + Meal (FEDL) ; 25 g + Fasted (FASTH)). RESULTS: Consumption of BH-BD effectively raised plasma r-BHB concentrations to 0.8-1.7 mM in all conditions, and both peak r-BHB concentration and r-BHB area under the curve were greater with 25 g versus 12.5 g of BH-BD. Urinary excretion of r-BHB was <1 g. Plasma concentration of the non-physiological isoform s-BHB was increased to 20-60 µM in all conditions. BH-BD consumption decreased plasma glucose and free fatty acid concentrations; insulin was increased when BH-BD was consumed with a meal. CONCLUSIONS: These results demonstrate that consumption of BH-BD effectively induces exogenous ketosis in healthy adults at rest.


Assuntos
Ésteres , Cetose , Adulto , Humanos , Ácido 3-Hidroxibutírico , Hidroxibutiratos , Corpos Cetônicos , Cetonas
9.
Nutrients ; 13(6)2021 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-34198888

RESUMO

BACKGROUND: Foods rich in saturated fatty acids (SFAs) have been discouraged by virtue of their cholesterol-raising potential, but this effect is modulated by the food source and background level of carbohydrate. OBJECTIVE: We aimed to compare the consumption of palm stearin (PS) versus butter on circulating cholesterol responses in the setting of both a low-carbohydrate/high-fat (LC/HF) and high-carbohydrate/low-fat (HC/LF) diet in healthy subjects. We also explored effects on plasma lipoprotein particle distribution and fatty acid composition. METHODS: We performed a randomized, controlled-feeding, cross-over study that compared a PS- versus a Butter-based diet in a group of normocholesterolemic, non-obese adults. A controlled canola oil-based 'Run-In' diet preceded the experimental PS and Butter diets. All diets were eucaloric, provided for 3-weeks, and had the same macronutrient distribution but varied in primary fat source (40% of the total fat). The same Run-In and cross-over experiments were done in two separate groups who self-selected to either a LC/HF (n = 12) or a HC/LF (n = 12) diet track. The primary outcomes were low-density lipoprotein-cholesterol (LDL-C), high-density lipoprotein (HDL)-C, triglycerides, and LDL particle distribution. RESULTS: Compared to PS, Butter resulted in higher LDL-C in both the LC/HF (13.4%, p = 0.003) and HC/LF (10.8%, p = 0.002) groups, which was primarily attributed to large LDL I and LDL IIa particles. There were no differences between PS and Butter in HDL-C, triglycerides, or small LDL particles. Oxidized LDL was lower after PS than Butter in LC/HF (p = 0.011), but not the HC/LF group. CONCLUSIONS: These results demonstrate that Butter raises LDL-C relative to PS in healthy normocholesterolemic adults regardless of background variations in carbohydrate and fat, an effect primarily attributed to larger cholesterol-rich LDL particles.


Assuntos
Manteiga , Colesterol/sangue , Dieta/métodos , Carboidratos da Dieta/administração & dosagem , Gorduras na Dieta/administração & dosagem , Óleo de Palmeira/administração & dosagem , Adulto , Idoso , Estudos Cross-Over , Dieta/efeitos adversos , Dieta da Carga de Carboidratos/efeitos adversos , Dieta da Carga de Carboidratos/métodos , Dieta com Restrição de Carboidratos/efeitos adversos , Dieta com Restrição de Carboidratos/métodos , Dieta com Restrição de Gorduras/efeitos adversos , Dieta com Restrição de Gorduras/métodos , Dieta Hiperlipídica/efeitos adversos , Dieta Hiperlipídica/métodos , Feminino , Voluntários Saudáveis , Humanos , Lipídeos/sangue , Masculino , Pessoa de Meia-Idade , Óleo de Palmeira/química , Adulto Jovem
10.
Nutrients ; 13(3)2021 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-33802651

RESUMO

Ketogenic diets (KDs) often contain high levels of saturated fat, which may increase liver fat, but the lower carbohydrate intake may have the opposite effect. Using a controlled feeding design, we compared liver fat responses to a hypocaloric KD with a placebo (PL) versus an energy-matched low-fat diet (LFD) in overweight adults. We also examined the added effect of a ketone supplement (KS). Overweight adults were randomized to a 6-week KD (KD + PL) or a KD with KS (KD + KS); an LFD group was recruited separately. All diets were estimated to provide 75% of energy expenditure. Weight loss was similar between groups (p > 0.05). Liver fat assessed by magnetic resonance imaging decreased after 6 week (p = 0.004) with no group differences (p > 0.05). A subset with nonalcoholic fatty liver disease (NAFLD) (liver fat > 5%, n = 12) showed a greater reduction in liver fat, but no group differences. In KD participants with NAFLD, 92% of the variability in change in liver fat was explained by baseline liver fat (p < 0.001). A short-term hypocaloric KD high in saturated fat does not adversely impact liver health and is not impacted by exogenous ketones. Hypocaloric low-fat and KDs can both be used in the short-term to significantly reduce liver fat in individuals with NAFLD.


Assuntos
Dieta com Restrição de Gorduras , Dieta Cetogênica , Suplementos Nutricionais , Gorduras/análise , Cetonas/uso terapêutico , Fígado/química , Sobrepeso/dietoterapia , Adulto , Dieta com Restrição de Gorduras/métodos , Dieta Cetogênica/métodos , Gorduras/metabolismo , Feminino , Humanos , Fígado/diagnóstico por imagem , Fígado/metabolismo , Imageamento por Ressonância Magnética , Masculino , Sobrepeso/metabolismo
11.
Front Nutr ; 8: 618520, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33869263

RESUMO

Background: Ketogenic diets (KDs) that elevate beta-hydroxybutyrate (BHB) promote weight and fat loss. Exogenous ketones, such as ketone salts (KS), also elevate BHB concentrations with the potential to protect against muscle loss during caloric restriction. Whether augmenting ketosis with KS impacts body composition responses to a well-formulated KD remains unknown. Purpose: To explore the effects of energy-matched, hypocaloric KD feeding (<50 g carbohydrates/day; 1.5 g/kg/day protein), with and without the inclusion of KS, on weight loss and body composition responses. Methods: Overweight and obese adults were provided a precisely defined hypocaloric KD (~75% of energy expenditure) for 6 weeks. In a double-blind manner, subjects were randomly assigned to receive ~24 g/day of a racemic BHB-salt (KD + KS; n = 12) or placebo (KD + PL; n = 13). A matched comparison group (n = 12) was separately assigned to an isoenergetic/isonitrogenous low-fat diet (LFD). Body composition parameters were assessed by dual x-ray absorptiometry and magnetic resonance imaging. Results: The KD induced nutritional ketosis (>1.0 mM capillary BHB) throughout the study (p < 0.001), with higher fasting concentrations observed in KD + KS than KD + PL for the first 2 weeks (p < 0.05). There were decreases in body mass, whole body fat and lean mass, mid-thigh muscle cross-sectional area, and both visceral and subcutaneous adipose tissues (p < 0.001), but no group differences between the two KDs or with the LFD. Urine nitrogen excretion was significantly higher in KD + PL than LFD (p < 0.01) and trended higher in KD + PL compared to KD + KS (p = 0.076), whereas the nitrogen excretion during KD + KS was similar to LFD (p > 0.05). Conclusion: Energy-matched hypocaloric ketogenic diets favorably affected body composition but were not further impacted by administration of an exogenous BHB-salt that augmented ketosis. The trend for less nitrogen loss with the BHB-salt, if manifested over a longer period of time, may contribute to preserved lean mass.

12.
NMR Biomed ; 33(7): e4317, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32363644

RESUMO

A low field strength (B0) system could increase cardiac MRI availability for patients otherwise contraindicated at higher field. Lower equipment costs could also broaden cardiac MR accessibility. The current study investigated the feasibility of cardiac function with steady-state free precession and flow assessment with phase contrast (PC) cine images at 0.35 T, and evaluated differences in myocardial relaxation times using quantitative T1, T2 and T2* maps by comparison with 1.5 and 3 T results in a small cohort of six healthy volunteers. Signal-to-noise ratio (SNR) differences across systems were characterized with proton density-weighted spin echo phantom data. SNR at 0.35 T was lower by factors of 5.5 and 15.0 compared with the 1.5 and 3 T systems used in this study. All cine images at 0.35 T scored 3 or greater on a five-point image quality scale. Normalized blood-myocardium contrast in cine images, left ventricular volumes (end diastolic volume, end systolic volume) and function (ejection fraction and stroke volume) measures at 0.35 T matched 1.5 and 3 T results. Phase-to-noise ratio in 0.35 T PC images (11.7 ± 1.9) was lower than 1.5 T (18.7 ± 5.2) and 3 T (44.9 ± 16.5). Peak velocity and stroke volume determined from PC images were similar across systems. Myocardial T1 increased (564 ± 13 ms at 0.35 T, 955 ± 19 ms at 1.5 T and 1200 ± 35 ms at 3 T) while T2 (59 ± 4 ms at 0.35 T, 49 ± 3 ms at 1.5 T and 40 ± 2 ms at 3 T) and T2* (42 ± 8 ms at 0.35 T, 33 ± 6 ms at 1.5 T and 24 ± 3 ms at 3 T) decreased with increasing B0. Despite SNR deficits, cardiovascular function, flow assessment and myocardial relaxation parameter mapping is feasible at 0.35 T using standard cardiovascular imaging sequences.


Assuntos
Coração/fisiologia , Miocárdio/metabolismo , Feminino , Humanos , Interpretação de Imagem Assistida por Computador , Imagem Cinética por Ressonância Magnética , Masculino , Imagens de Fantasmas
13.
JCI Insight ; 4(12)2019 06 20.
Artigo em Inglês | MEDLINE | ID: mdl-31217353

RESUMO

BACKGROUNDMetabolic syndrome (MetS) is highly correlated with obesity and cardiovascular risk, but the importance of dietary carbohydrate independent of weight loss in MetS treatment remains controversial. Here, we test the theory that dietary carbohydrate intolerance (i.e., the inability to process carbohydrate in a healthy manner) rather than obesity per se is a fundamental feature of MetS.METHODSIndividuals who were obese with a diagnosis of MetS were fed three 4-week weight-maintenance diets that were low, moderate, and high in carbohydrate. Protein was constant and fat was exchanged isocalorically for carbohydrate across all diets.RESULTSDespite maintaining body mass, low-carbohydrate (LC) intake enhanced fat oxidation and was more effective in reversing MetS, especially high triglycerides, low HDL-C, and the small LDL subclass phenotype. Carbohydrate restriction also improved abnormal fatty acid composition, an emerging MetS feature. Despite containing 2.5 times more saturated fat than the high-carbohydrate diet, an LC diet decreased plasma total saturated fat and palmitoleate and increased arachidonate.CONCLUSIONConsistent with the perspective that MetS is a pathologic state that manifests as dietary carbohydrate intolerance, these results show that compared with eucaloric high-carbohydrate intake, LC/high-fat diets benefit MetS independent of whole-body or fat mass.TRIAL REGISTRATIONClinicalTrials.gov Identifier: NCT02918422.FUNDINGDairy Management Inc. and the Dutch Dairy Association.


Assuntos
Carboidratos da Dieta/metabolismo , Síndrome Metabólica/metabolismo , Obesidade/metabolismo , Redução de Peso , Ácido 8,11,14-Eicosatrienoico/sangue , Adulto , Idoso , Ácido Araquidônico/sangue , LDL-Colesterol/metabolismo , Estudos Cross-Over , Dieta , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
14.
Mil Med ; 184(9-10): e538-e547, 2019 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-30877806

RESUMO

INTRODUCTION: Ketogenic diets (KDs) that elevate ketones into a range referred to as nutritional ketosis represent a possible nutrition approach to address the emerging physical readiness and obesity challenge in the military. An emerging body of evidence demonstrates broad-spectrum health benefits attributed to being in nutritional ketosis, but no studies have specifically explored the use of a KD in a military population using daily ketone monitoring to personalize the diet prescription. MATERIALS AND METHODS: To evaluate the feasibility, metabolic, and performance responses of an extended duration KD, healthy adults (n = 29) from various military branches participated in a supervised 12-wk exercise training program. Fifteen participants self-selected to an ad libitum KD guided by daily measures of capillary blood ketones and 14 continued their normal mixed diet (MD). A battery of tests were performed before and after the intervention to assess changes in body mass, body composition, visceral fat, liver fat, insulin sensitivity, resting energy metabolism, and physical performance. RESULTS: All KD subjects were in nutritional ketosis during the intervention as assessed by daily capillary beta-hydroxybutyrate (ßHB) (mean ßHB 1.2 mM reported 97% of all days) and showed higher rates of fat oxidation indicative of keto-adaptation. Despite no instruction regarding caloric intake, the KD group lost 7.7 kg body mass (range -3.5 to -13.6 kg), 5.1% whole-body percent fat (range -0.5 to -9.6%), 43.7% visceral fat (range 3.0 to -66.3%) (all p < 0.001), and had a 48% improvement in insulin sensitivity; there were no changes in the MD group. Adaptations in aerobic capacity, maximal strength, power, and military-specific obstacle course were similar between groups (p > 0.05). CONCLUSIONS: US military personnel demonstrated high adherence to a KD and showed remarkable weight loss and improvements in body composition, including loss of visceral fat, without compromising physical performance adaptations to exercise training. Implementation of a KD represents a credible strategy to enhance overall health and readiness of military service members who could benefit from weight loss and improved body composition.


Assuntos
Dieta Cetogênica/normas , Militares/estatística & dados numéricos , Condicionamento Físico Humano/fisiologia , Ácido 3-Hidroxibutírico/análise , Ácido 3-Hidroxibutírico/sangue , Tecido Adiposo/fisiologia , Adulto , Composição Corporal/fisiologia , Dieta Cetogênica/métodos , Dieta Cetogênica/estatística & dados numéricos , Feminino , Humanos , Masculino , Estado Nutricional , Ohio , Condicionamento Físico Humano/métodos , Condicionamento Físico Humano/estatística & dados numéricos , Aptidão Física/fisiologia , Estudos Prospectivos , Redução de Peso/fisiologia
15.
Tomography ; 5(4): 358-366, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31893234

RESUMO

Excess visceral adipose tissue (VAT) and VAT volume relative to subcutaneous adipose tissue (SAT) are associated with elevated health risks. This study compares fat measurements by dual-energy X-ray absorptiometry (DXA) and magnetic resonance imaging (MRI). In total, 21 control subjects (Control) and 16 individuals with metabolic syndrome (MetSyn) were scanned by DXA and MRI. The region measured by MRI was matched to the android region defined by DXA, and MRI reproducibility was also evaluated. In addition, liver fat fraction was quantified via MRI and whole-body fat by DXA. VAT measurements are interchangeable between DXA and MRI in the Control (R = 0.946), MetSyn (R = 0.968), and combined cohort (R = 0.983). VAT/SAT ratio did not differ in the Control group (P = .10), but VAT/SAT ratio measured by DXA was significantly higher in the MetSyn group (P < .01) and the combined (P = .03) cohort. Intraobserver (ICC = 0.998) and interobserver (ICC = 0.977) reproducibility of MRI VAT measurements was excellent. Liver fat fraction by MRI was higher (P = .001) in MetSyn (12.4% ± 7.6%) than in controls (2.6% ± 2.2%), as was whole-body fat percentage by DXA (P = .001) between the MetSyn (42.0% ± 8.1%) and Control groups (26.7% ± 6.9%). DXA and MRI VAT are interchangeable when measured over an anatomically matched region of the abdomen, while SAT and VAT/SAT ratio differ between the 2 modalities.


Assuntos
Absorciometria de Fóton , Gordura Intra-Abdominal/diagnóstico por imagem , Imageamento por Ressonância Magnética , Feminino , Humanos , Masculino , Síndrome Metabólica/diagnóstico por imagem , Gordura Subcutânea/diagnóstico por imagem
16.
Hawaii J Med Public Health ; 74(7): 224-9, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26225267

RESUMO

Schools of Public Health have a wide variety of essential stakeholders. Broad input in program planning should assist in ensuring well-developed plans and strong community buy-in. The planning of a school can better address the needs of multiple stakeholders from systematic broad-based input from these constituents using concept mapping. In this study, we used concept mapping to prioritize a set of recommendations from diverse stakeholders to assist in the process of planning a school. A set of statements was generated on essential elements for the proposed school from a broad group of stakeholders. The statements were then distilled into unique themes, which were then rated on importance and feasibility. Cluster maps and pattern matches were used to analyze the ratings. Unique themes (N = 147) were identified and grouped into 12 clusters. Cluster themes included leadership, faculty, culture, school, and curriculum. Pattern matches revealed a significant, modest correlation between importance and feasibility (r = 0.27). A broad range of perspectives was used to identify relevant areas to address in the development of a school.


Assuntos
Desenvolvimento de Programas , Faculdades de Saúde Pública/organização & administração , Pesquisa Participativa Baseada na Comunidade , Currículo , Docentes/organização & administração , Havaí , Humanos , Liderança , Cultura Organizacional , Pesquisa em Sistemas de Saúde Pública
17.
Artigo em Inglês | MEDLINE | ID: mdl-25981422

RESUMO

INTRODUCTION: The traditional centralized approach to disaster preparedness fails to take into consideration the unique geographic, historic, cultural, and social needs of communities. It often puts vulnerable communities more at risk by directing them to follow a one-size-fits-all model. Community-based participatory research (CBPR) approaches can increase awareness and customize the disaster reduction strategies to meet a community's unique needs. OBJECTIVE: To partner with a vulnerable community in Hawaii in conducting a hazard-specific vulnerability and capability assessment utilizing PhotoVoice and the core principles of CBPR. METHODS: A community participated in a PhotoVoice project to identify and categorize their vulnerabilities and capabilities, identify gaps, and develop solutions or strategies to reduce their vulnerability to a tsunami. RESULTS: Forty-two vulnerabilities and 50 capabilities within the community were identified and then categorized through photo presentations and discussion sessions. These were sorted into 17 themes, including communications, accessibility, historic and cultural, emergency notification, food, and water. Based on the vulnerability and capability assessment, 13 gaps were then identified and discussed, yielding 16 feasible strategies to reduce the community's vulnerability. CONCLUSIONS: PhotoVoice was found to be a successful community-based participatory process to assist a vulnerable community to develop contextually appropriate disaster reduction strategies through visual dialogue, which increased community awareness, engagement, and capacity.


Assuntos
Planejamento em Desastres/organização & administração , Desastres/prevenção & controle , Fotografação , Desenvolvimento de Programas , Pesquisa Participativa Baseada na Comunidade , Havaí
18.
Mycologia ; 102(6): 1229-39, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20943573

RESUMO

Fungi and vascular plant interactions are necessary components of natural community establishment, productivity and degradation. While many fungal species serve as decomposers of organic matter, others have evolved mutualistic or parasitic relationships with vascular plants. This research focused on characterizing associations among macrofungi, vascular plant communities and soils. Ha Ha Tonka State Park is in central Missouri and has a varying landscape with numerous natural community types that provide diverse habitats and microhabitats that are ideally suited to the investigation of fungal, floral and soil associations. Five communities sampled within the park included glades, open woodlands, flatwoods, closed-canopy forests and karst sinks. Permanent 0.01 ha. plots were surveyed in the 2006 and 2007 growing seasons. Surveys of plots and entire communities yielded 249 fungal taxa and approximately 265 floral taxa. Soils were analyzed to help define specific edaphic components of each community and used to associate soil attributes with plant and fungal communities. Forest communities contained the most ectomycorrhizal (ECM) fungi species. Karst sinks and glades had higher soil pH and phosphorus and fewer ectomycorrhizal fungi. Statistical analyses included non-metric multidimensional scaling, multiresponse permutation procedure and indicator species analysis. Indicator species were identified for flatwood, forest and karst communities, but results were inconclusive for glades and open woodlands.


Assuntos
Ecossistema , Fungos/isolamento & purificação , Micorrizas/isolamento & purificação , Plantas/microbiologia , Microbiologia do Solo , Fungos/classificação , Missouri , Micorrizas/classificação , Estações do Ano
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