Matching Items (13)

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Relationship between resting energy expenditure and sleep parameters on gestational weight gain and the mediation effect of macronutrient composition

Description

No studies have evaluated the impact of tracking resting energy expenditure (REE) and modifiable health behaviors on gestational weight gain (GWG). In this controlled trial, pregnant women aged >18 years

No studies have evaluated the impact of tracking resting energy expenditure (REE) and modifiable health behaviors on gestational weight gain (GWG). In this controlled trial, pregnant women aged >18 years (X=29.8±4.9 years) with a gestational age (GA) <17 weeks were randomized to Breezing™ (N=16) or control (N=12) for 13 weeks. The Breezing™ group used a real-time metabolism tracker to obtain REE. Anthropometrics, diet, and sleep data were collected every 2 weeks. Rate of GWG was calculated as weight gain divided by total duration. Early (GA weeks 14-21), late (GA weeks 21-28), and overall (GA week 14-28) changes in macronutrients, sleep, and GWG were calculated. Mediation models were constructed using SPSS PROCESS macro using a bootstrap estimation approach with 10,000 samples. The majority of women were non-Hispanic Caucasian (78.6%). A total of 35.7% (n=10), 35.7% (n=10), and 28.6% (n=8) were normal weight, overweight, and obese, respectively, with 83.3% (n=10) and 87.5% (n=14) of the Control and Breezing™ groups gaining above IOM GWG recommendations. At baseline, macronutrient consumption did not differ. Overall (Breezing™ vs. Control; M diff=-349.08±150.77, 95% CI: -660.26 to -37.90, p=0.029) and late (M diff=-379.90±143.89, 95% CI:-676.87 to -82.93, p=0.014) changes in energy consumption significantly differed between the groups. Overall (M diff=-22.45±11.03, 95% CI: -45.20 to 0.31, p=0.053), late (M diff=-23.16±11.23, 95% CI: -46.33 to 0.01, p=0.05), and early (M diff=20.3±10.19, 95% CI: -0.74 to 41.34, p=0.058) changes in protein differed by group. Nocturnal total sleep time differed by study group (Breezing vs. Control; M diff=-32.75, 95% CI: -68.34 to 2.84, p=0.069). There was a 11.5% increase in total REE throughout the study. Early changes in REE (72±211 kcals) were relatively small while late changes (128±294 kcals) nearly doubled. Interestingly, early changes in REE demonstrated a moderate, positive correlation with rates of GWG later in pregnancy (r=0.528, p=0.052), suggesting that REE assessment early in pregnancy may help predict changes in GWG. Changes in macronutrients did not mediate the relationship between the intervention and GWG, nor did sleep mediate relationships between dietary intake and GWG. Future research evaluating REE and dietary composition throughout pregnancy may provide insight for appropriate GWG recommendations.

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Agent

Created

Date Created
  • 2019

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Will a novel organometallic complex mitigate the effects of hypertension in rats fed a high fat diet?

Description

Background: Nearly 95% of Americans will develop hypertension, and 67% will not seek treatment. Furthermore, hypertension is the leading risk factor for coronary heart disease. While previous studies have increased

Background: Nearly 95% of Americans will develop hypertension, and 67% will not seek treatment. Furthermore, hypertension is the leading risk factor for coronary heart disease. While previous studies have increased the use of blood pressure medication among patients that have received hypertension education, medications may not work for everyone. Due to the life-threatening nature of this condition, it is essential to find an effective alternative for treatment. The purpose of this study was to examine the impact of organometallic complex supplementation on hypertension and left ventricular hypertrophy in 6-week old male Sprague-Dawley rats that were fed either standard rodent chow or a high fat diet for 10 weeks at a university in Arizona.

Methods: Forty-two healthy six-week old male Sprague-Dawley rats were randomly assigned to one of three groups: plain water control, 0.6 mg/ml organometallic complex or 3.0 mg/ml organometallic complex as soon as they arrived. Each rat was then housed individually to prevent the sharing of microbiota through coprophagia. Rats in each treatment group were further divided into two dietary groups that were fed either a high fat diet containing 60% kcal fat that was changed every three days or standard rodent chow. Researchers were not blind to which rat was in each group. At the end of the 10-week study, rats were euthanized with an overdose of sodium pentobarbital (200 mg/kg, i.p.). Heart, left ventricle of the heart, liver, and spleen masses were recorded for each animal. Data were analyzed by two-way ANOVA using SigmaPlot 10.0 software.

Results: At the conclusion of this study, the left ventricle mass of the rats in the high fat diet group were significantly larger than those in the chow group. Neither dose of the organometallic complex supplement prevented these effects induced by high fat feeding.

Conclusion: The organometallic complex supplement was not effective at mitigating the effects of a high fat diet on cardiac hypertrophy in rats. Therefore, this supplement should not be used to treat cardiac hypertrophy.

Contributors

Agent

Created

Date Created
  • 2019

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Challenges to Skeletal Muscle During Advancing Age: A Translational Approach

Description

The purpose of this dissertation was 1) to develop noninvasive strategies to assess skeletal muscle size, architecture, and composition in young and old adults (study #1) and 2) evaluate the

The purpose of this dissertation was 1) to develop noninvasive strategies to assess skeletal muscle size, architecture, and composition in young and old adults (study #1) and 2) evaluate the impact of chemotherapeutic treatment on skeletal muscle satellite cells and capillaries (study #2). For study #1 ultrasound images were obtained from the quadriceps muscles of young (8 m, 8 f) and older (7 m, 5 f) participants on two occasions, separated by 5-15 days. Images were collected while the participants were both standing and supine, and were analyzed for muscle thickness, pennation angle, and echogenicity. In addition, test-retest reliability and ICCs were evaluated for each posture and when imaging sites remained marked or were re-measured from visit #1 to visit #2. Generally, in both younger and older adults muscle thickness was greater and echogenicity was lower in the anterior quadriceps when images were collected standing versus supine. Maintaining the imaging site between visits did not influence test re-test reliability for either age group. Older adults exhibited smaller muscle thickness, lower pennation angle and increased echogenicity. Further, variability for the use of ultrasound to determine muscle thickness and pennation angle was greater in older versus younger adults. Findings from study #1 highlight several methodological considerations for US-based assessment of skeletal muscle characteristics that should be considered for improving reproducibility and generalizability of US to assess skeletal muscle characteristics and function across the aging spectrum. This is particularly relevant given the emerging use of ultrasound to assess skeletal muscle characteristics in healthy and clinical populations. In the second study, ovariectomized female Sprague-Dawley rats were randomized to receive three bi-weekly intraperitoneal injections of the chemotherapeutic drug, Doxorubicin (DOX) (4mg/kg; cumulative dose 12mg/kg) or vehicle (VEH; saline). Animals were euthanized 5d following the last injection, and the soleus (SOL) and extensor digitorum longus (EDL) muscles were dissected and prepared for immunohistochemical and RT-qPCR analyses. Relative to VEH, cross-sectional area (CSA) of the SOL and EDL muscle fibers were 26% and 33% smaller, respectively, in DOX animals (P<0.05). In the SOL satellite cell and capillary densities were 39% and 35% lower, respectively, in DOX animals (P<0.05), whereas in the EDL satellite cell and capillary densities were unaffected by DOX administration (P>0.05). In the SOL MYF5 mRNA expression was increased in DOX animals (P<0.05), while in the EDL MGF mRNA expression was reduced in DOX animals (P<0.05). Chronic DOX administration is associated with reduced fiber size in multiple skeletal muscles, however DOX appears to impact the satellite cell and capillary densities in a muscle-specific manner. These findings from study #2 highlight that therapeutic targets to protect skeletal muscle from DOX may vary across muscles. Collectively, these findings 1) improve the ability to examine muscle size and function in younger and older adults, and 2) identify promising therapeutic targets to protect skeletal muscle from the harmful effects of chemotherapy treatment.

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Agent

Created

Date Created
  • 2018

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Longitudinal social networks impacts on weight and weight-related behaviors assessed using mobile-based ecological momentary assessments: Study Protocols for the SPARC study

Description

Background

The transition from the home to college is a phase in which emerging adults shift toward more unhealthy eating and physical activity patterns, higher body mass indices, thus increasing

Background

The transition from the home to college is a phase in which emerging adults shift toward more unhealthy eating and physical activity patterns, higher body mass indices, thus increasing risk of overweight/obesity. Currently, little is understood about how changing friendship networks shape weight gain behaviors. This paper describes the recruitment, data collection, and data analytic protocols for the SPARC (Social impact of Physical Activity and nutRition in College) study, a longitudinal examination of the mechanisms by which friends and friendship networks influence nutrition and physical activity behaviors and weight gain in the transition to college life.

Methods

The SPARC study aims to follow 1450 university freshmen from a large university over an academic year, collecting data on multiple aspects of friends and friendship networks. Integrating multiple types of data related to student lives, ecological momentary assessments (EMAs) are administered via a cell phone application, devilSPARC. EMAs collected in four 1-week periods (a total of 4 EMA waves) are integrated with linked data from web-based surveys and anthropometric measurements conducted at four times points (for a total of eight data collection periods including EMAs, separated by ~1 month). University databases will provide student card data, allowing integration of both time-dated data on food purchasing, use of physical activity venues, and geographical information system (GIS) locations of these activities relative to other students in their social networks.

Discussion

Findings are intended to guide the development of more effective interventions to enhance behaviors among college students that protect against weight gain during college.

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Agent

Created

Date Created
  • 2016-08-30

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Effects of a fat-sugar supplemented diet, with and without exercise training, on body fat mass and selected cardiometabolic risk markers in overweight and obese, sedentary males

Description

The winter holiday period has been highlighted as a major risk period for weight gain due to excess caloric intake in the form of fat and sugar. Furthermore, diets high

The winter holiday period has been highlighted as a major risk period for weight gain due to excess caloric intake in the form of fat and sugar. Furthermore, diets high in fat and sugar have been implicated in the pathogenesis of diabetes and cardiovascular disease. Exercise aids in the prevention of weight/fat gain, and prevents deleterious changes in cardiometabolic function. The objective of this study was to examine the effects of a fat-sugar supplemented diet, with and without two different exercise training protocols, on body composition, glycemic control and other markers of cardiovascular disease in an at-risk population of overweight and obese males. Twenty-seven, healthy overweight/obese (BMI >25 kg/m2) males were fed 2 donuts per day, 6 days/week, for four weeks, while maintaining their current diet. In addition, all subjects were randomized to one of the following conditions: sedentary control, 1,000 kcal/week moderate-intensity continuous training (MICT) (50% of peak oxygen consumption), or 1,000 kcal/week high-intensity interval training (HIIT) (90-95% of peak heart rate). Supervised exercise training was performed 4 days/week on a cycle ergometer. Changes in body weight and composition, endothelial function, arterial stiffness, glycemic control, blood lipids and cardiorespiratory fitness (CRF) were assessed before and after the intervention. Body weight, lean mass and visceral fat increased significantly in HIIT (p<0.05) and were unchanged in MICT. There was a trend for a significant increase in body weight (p=0.07) and lean mass (p=0.11) in control. Glycemic control during the 2-h OGTT improved significantly in MICT and control, with no change in HIIT. Hepatic insulin resistance index (IRI) and 30-min insulin during the OGTT improved significantly after MICT and worsened following control (p=0.03), while HIIT was unchanged. CRF increased significantly in both HIIT and MICT, with no change in control (p<0.001). There were no significant changes in other markers of cardiovascular disease. The addition of a fat-sugar supplement (~14,500 kcal) over a 4-week period was not sufficient to induce deleterious changes in body composition and cardiometabolic health in overweight/obese young males. Exercise training did not afford overweight/obese males additional health benefits, with the exception of improvements in fitness and hepatic IRI.

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Agent

Created

Date Created
  • 2016

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Gut microbiome diversity and community structure following dietary genistein treatment in a murine model of cystic fibrosis

Description

Introduction: Cystic fibrosis (CF) is the most common life-shortening autosomal recessive genetic disease affecting Caucasians. The disease is characterized by a dysfunctional cystic fibrosis transmembrane regulator (CFTR) protein and aberrant

Introduction: Cystic fibrosis (CF) is the most common life-shortening autosomal recessive genetic disease affecting Caucasians. The disease is characterized by a dysfunctional cystic fibrosis transmembrane regulator (CFTR) protein and aberrant mucus accumulation that subsequently alters the physicochemical environment in numerous organ systems. These mucosal perturbations have been associated with inflammation and microbial dysbiosis, most notably in the lungs and gastrointestinal (GI) tract. Genistein, a soy isoflavone and dietary polyphenol, has been shown to modulate CFTR function in cell cultures and murine models, as well exert sex-dependent improvement of survival rates in a CF mouse model. However, it is unknown whether dietary genistein affects gut microbiome diversity and community structure in cystic fibrosis. This study sought to examine associations between dietary genistein treatment and gut microbiome diversity and community structure in a murine model of CF. Methods: Twenty-four male and female mice homozygous for the DF508 CFTR gene mutation were maintained on one of three diet regimens for a 45-day period (n=11, standard chow; n=7, Colyte-treated water and standard chow; n=6, 600 mg dietary genistein per kg body weight). One fecal pellet was collected per mouse post-treatment, and microbial genomic DNA was extracted from the fecal samples, quantified, amplified, and sequenced on the Illumina MiSeq platform. QIIME 2 was used to conduct alpha- and beta-diversity analyses on all samples. Results: Measures of alpha-diversity were significantly decreased in the dietary genistein group as compared to either standard chow or Colyte groups. Measures of beta-diversity showed that community structure differed significantly between dietary treatment groups; these differences were further illustrated by distinct clustering of taxa as shown by principal coordinates analysis plots. Conclusion: This 3-arm parallel experimental study showed that dietary genistein treatment was associated with decreased microbial diversity and differences in microbial community structure in DF508 mice.

Contributors

Agent

Created

Date Created
  • 2019

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The Use of a Verification Phase in Determination of VO2max in Older Adults

Description

Maximal oxygen uptake (VO2max) declines with age and is a predictor of morbidity and mortality risks. Due to these implications, accurate assessment and determination of VO2max are important for the

Maximal oxygen uptake (VO2max) declines with age and is a predictor of morbidity and mortality risks. Due to these implications, accurate assessment and determination of VO2max are important for the older population. Without the presence of a VO2 plateau, secondary criteria are used to determine whether the test resulted in a maximal value. However, inconsistent secondary criteria do not account for intersubject variability. To circumvent this issue, a verification phase following a traditional ramp assessment may be utilized. The purpose of this study was to compare verification phase strategies in older adults. A secondary purpose of this study was to examine the repeatability of the ramp assessment performed during each visit. Twenty-two older adults between 60 and 80 years of age were recruited to participate in the study. Each subject completed two experimental trials in a randomized, counterbalanced cross-over design. Both trials consisted of a ramp test and verification phase at either 85% (VP85) or 110% (VP110) of the peak work rate achieved during the ramp (Ramp85 and Ramp110, respectively). Expired gases and heart rate (HR) were monitored continuously and measured every ten seconds. VO2peak was determined by the highest 30-second averages for the ramp and verification phases. No significant differences were observed for absolute (L/min) VO2peak between VP85 (P = 0.679) or VP110 (P = 0.200) and the associated ramp. There was also no significant difference in maximal HR between VP85 (P = 0.243) or VP110 (P = 0.085) and the associated ramp. However, individual data shows that 36% of individuals achieved a 2% greater VO2 (L/min) during the VP85 compared to the Ramp85, while only 15% of subjects achieved a 2% greater VO2 (L/min) during the VP110 compared to Ramp110. No significant differences (P < 0.05) were found for most variables between Ramp1 and Ramp2. These data suggest that if a verification phase is employed for VO2max assessment in otherwise healthy older adults, a power slightly below peak work rate may provide a more accurate assessment compared to a power slightly above peak work rate.

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Agent

Created

Date Created
  • 2019

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A pilot study to assess nutrition knowledge and behaviors of low-income, pregnant adolescents and adult women

Description

Low income, pregnant adolescents have an increased risk of adverse pregnancy outcomes, such as preterm birth, delivery of low birth weight babies and excessive gestational weight gain that increases the

Low income, pregnant adolescents have an increased risk of adverse pregnancy outcomes, such as preterm birth, delivery of low birth weight babies and excessive gestational weight gain that increases the risk of postpartum overweight and obesity. Inadequate dietary intake is a modifiable risk factor that may differentially impact maternal health and fetal outcomes for pregnant adults and adolescents. To evaluate the effectiveness of a social media intervention on improving prenatal health knowledge and dietary intake, 22 racially diverse pregnant women (59% Black and 36% White) were recruited and adolescent (n=10) outcomes compared to those of adults (n=12) across the intervention. Pre- and post-intervention nutrition knowledge questionnaires and diet recalls were completed to assess nutrition knowledge and dietary intake. When assessing dietary change across the intervention, significant decreases in fat (pre vs. post, 97.9 ± 0.2 g vs. 90.2 ± 0.2 g, P=0.047) and folate intake (pre vs. post, 537.6 ± 0.3 μg vs. 531.2 ± 0.2 μg, P=0.041) were observed while significant increases in carbohydrate (pre vs. post, 318.9 ± 0.2 g vs. 335.9 ± 0.2 g, P<0.001), calcium (pre vs. post, 851.3 ± 0.3 mg vs. 893.5 ± 0.2 mg, P<0.001) and magnesium intakes (pre vs. post, 212.9 ± 0.2 mg vs. 227.8 ± 0.2 mg, P<0.001) occurred. These time effects occurred independent of group (adolescents vs. adults) as time*group interactions were not significant (p>0.05) with the exception of sugar intake. Increases in sugar intake across the intervention were greater among the adolescent group (adolescent vs. adult, 7.9 ± 0.2 g vs. 6.0 ± 0.2 g, P=0.023). Overall nutrition knowledge was limited and confusion regarding MyPlate recommendations persisted. The inadequate dietary behaviors observed suggest that future interventions should focus education on specific dietary nutrients such as added sugars and fiber to improve dietary intakes. The best way to actively engage pregnant adolescents is unknown: however, social media has the potential to reach teens and low-income women with education that may be key in allowing interventions to change dietary habits and behaviors.

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Agent

Created

Date Created
  • 2016

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The Effects of Acute Aerobic and Resistance Exercise on mTOR Signaling and Autophagy in Human Skeletal Muscle

Description

Exercise serves as a powerful stimulus to induce skeletal muscle adaptation. For instance, it is well understood that aerobic exercise (AE) elicits an adaptive response ultimately leading to increased fatigue

Exercise serves as a powerful stimulus to induce skeletal muscle adaptation. For instance, it is well understood that aerobic exercise (AE) elicits an adaptive response ultimately leading to increased fatigue resistance and capillarization, whereas resistance exercise (RE) is known to elicit an adaptive response leading to increased muscle strength and size. However, the precise molecular mechanisms mediating these unique adaptations to different forms of exercise remain to be completely resolved. The purpose of this study was to investigate the adaptive cellular response of skeletal muscle following acute AE and RE. Specifically, this study focused on two molecular processes: 1) mammalian/mechanistic target of rapamycin (mTOR) signaling pathway, a regulator of muscle protein synthesis, and 2) autophagy, a process through which proteins and organelles are broken down in the muscle fiber. In a counterbalanced, crossover design, six healthy, recreationally active young men (27±3 yr) completed acute AE (40 min of cycling ~70% maximal HR) and acute RE [8 sets, 10 reps, ~65% 1-repetition maximum (1RM)] separated by ~1wk. Muscle biopsies (vastus lateralis) were obtained before, at 1 and 4h post exercise and western blot analyses were used to examine the phosphorylation of mTOR signaling proteins and various markers of autophagy. Phosphorylation of mTORSer2448 increased only following RE at 4h (P < 0.05). However, phosphorylation of p70S6K1Thr389, a downstream marker of mTOR, increased following both AE and RE at 4h (P < 0.05). However, p70S6K1Thr389 was phosphorylated to a greater extent at 1h following RE compared to AE (P < 0.05). LC3BII was decreased at 1h and 4h postexercise in response to both AE and RE (P < 0.05). These data indicate that both acute AE and RE stimulate, to some degree, mTOR signaling in skeletal muscle, a pathway associated with increased muscle protein synthesis. Further, based on markers examined in the current study, both acute AE and RE similarly stimulate autophagy, which is associated with muscle protein breakdown. These data indicate that, at least in the immediate hours post exercise, the unique adaptations to AE and RE exercise may be mediated through cellular pathways other than mTOR and autophagy.

Contributors

Agent

Created

Date Created
  • 2019

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Effects of muscle contraction frequency on blood glucose control, insulin sensitivity, endothelial function and blood pressure among obese males

Description

Cardiovascular disease and diabetes are major health burdens. Diabetes is a primary risk factor of cardiovascular disease, and there is a strong link between obesity and risk of developing diabetes.

Cardiovascular disease and diabetes are major health burdens. Diabetes is a primary risk factor of cardiovascular disease, and there is a strong link between obesity and risk of developing diabetes. With the prevalence of prediabetes highest among overweight/obese individuals, investigation into preventative strategies are needed. Aerobic exercise is a potent stimulus for both insulin and non-insulin dependent glucose uptake into the skeletal muscle. A single exercise session can improve insulin sensitivity within hours after exercise. The effects of intensity, type, and volume of exercise on glucose homeostasis have been studied extensively; however, controlling for muscle contraction frequency with a constant exercise intensity and workload has not been examined. The purpose of this study was to compare muscle contraction frequency during aerobic exercise by altering cycling cadence on insulin sensitivity and vascular health. Eleven obese males (age=28yr, BMI=35kg/m2) completed three conditions in random order: 1) control-no exercise; 2) 45-min cycling at 45 revolutions per minute (45RPM) at 65-75%VO2max; 3) 45-min cycling at 90RPM at 65-75%VO2max. Glucose control and insulin sensitivity were assessed with oral glucose tolerance tests (OGTT) 4 hours post-exercise. Vascular health was assessed via flow-mediated dilation (FMD) pre-exercise, 1-hr and 2-hr post exercise and ambulatory blood pressure was assessed pre-exercise, and continually every 15 min post-exercise. Linear mixed models were used to compare the mean differences in outcome variables. There were no significant differences found between control and both exercise conditions for all OGTT outcomes and no differences were found between control and exercise in FMD (all, p>0.05). Significant effects for exercise were found for both brachial and central blood pressure measures. Brachial systolic blood pressures were lower at 2- and 4-hr post-exercise by approximately -10 and -8mmHg, respectively (p<0.001 and p=0.004) versus control. Central systolic blood pressures were lower at 2-, 3-, and 4-hr post-exercise by approximately -8, -9 and -6mmHg, respectively (p<0.001, p=0.021 and p=0.004) versus control. In conclusion, aerobic exercise, regardless of muscle contraction frequency, were unable to effect glucose control and insulin sensitivity. Similarly, there was no effect on vascular function. However, there was a significant effect of aerobic exercise on reducing post-exercise blood pressure.

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Agent

Created

Date Created
  • 2017