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Intramuscular TNF-alpha signaling in response to resistance exercise and recovery in untrained males.
Title
Intramuscular TNF-alpha signaling in response to resistance exercise and recovery in untrained males.
Creator
Townsend, Jeremy, Stout, Jeffrey, Hoffman, Jay, Fukuda, David, Roberts, Michael, University of Central Florida
Abstract / Description
INTRODUCTION: The nuclear factor kappa B (NF-??) signaling cascade is responsible for mediating stress-activated catabolic effects of Tumor Necrosis Factor Alpha (TNF-?) downstream of the TNF receptor (TNFR1). NF-?? transcription factor remains inhibited in the cytosol of the muscle and can be stimulated for translocation and transcription by a variety of external stimuli, most notably by pro-inflammatory cytokines and oxidative stress. Nevertheless, currently there is a gap in the literature...
Show moreINTRODUCTION: The nuclear factor kappa B (NF-??) signaling cascade is responsible for mediating stress-activated catabolic effects of Tumor Necrosis Factor Alpha (TNF-?) downstream of the TNF receptor (TNFR1). NF-?? transcription factor remains inhibited in the cytosol of the muscle and can be stimulated for translocation and transcription by a variety of external stimuli, most notably by pro-inflammatory cytokines and oxidative stress. Nevertheless, currently there is a gap in the literature with regard to the time course effect of NF-?? signaling following acute resistance exercise in humans. PURPOSE: To observe the effects of an acute lower-body resistance exercise protocol and subsequent recovery on intramuscular NF- ?? signaling. METHODS: Twenty-eight untrained males were assigned to either a control (CON; n=11) or exercise group (EX; n=17) and completed a lower-body resistance exercise protocol consisting of the back squat, leg press, and leg extension exercises. Skeletal muscle microbiopsies were obtained from the vastus lateralis pre-exercise (PRE), 1-hour (1HR), 5-hour (5HR), and 48-hours (48HR) post-resistance exercise. Multiplex signaling assay kits (EMD Millipore, Billerica, MA, USA) were used to quantify the total protein (TNFR1, c-Myc) or phosphorylation status of proteins (IKKa/b, NF- ??, IkB) specific to apoptotic signaling pathways using MAGPIX(&)#174; (Luminex, Austin, TX, USA). Repeated measures ANOVA analysis was used to determine the effects of the exercise bout on intramuscular signaling at each timepoint. Additionally, change scores were analyzed by magnitude based inferences to determine a mechanistic interpretation. RESULTS: Repeated measures ANOVA indicated a trend for a two way interaction between the EX and CON Group (p=0.064). Magnitude based inferences revealed a (")Very Likely(") increase in total c-Myc from PRE-5H and a (")Likely(") increase in IkB phosphorylation from PRE-5H. CONCLUSION: Results indicate that c-Myc transcription factor and phosphorylation of IkB are elevated following acute intense resistance exercise in untrained males. These data suggest that NF- ?? signaling plays a role in ribosome biogenesis and skeletal muscle regeneration following resistance exercise in young untrained males.
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Date Issued
2016
Identifier
CFE0006191, ucf:51089
Format
Document (PDF)
PURL
http://purl.flvc.org/ucf/fd/CFE0006191
DEVELOPMENT OF A SET OF FORCE RESPONSE EQUATIONS TO REPRESENT THE MUSCULATURE IN INFANTS TO STUDY DEVELOPMENTAL DYSPLASIA OF THE HIP
Title
DEVELOPMENT OF A SET OF FORCE RESPONSE EQUATIONS TO REPRESENT THE MUSCULATURE IN INFANTS TO STUDY DEVELOPMENTAL DYSPLASIA OF THE HIP.
Creator
Jones, Brendan, Kassab, Alain, University of Central Florida
Abstract / Description
This paper describes how a force response equation was created to model muscles, tendons, and ligaments of the hip joint to improve a biomechanical model of an infant hip to study Developmental Dysplasia of the Hip (DDH). DDH is the most common abnormality in newborn infants and is defined as any amount of instability in the hip including complete dislocation. Researchers at our institution are attempting to increase the success rate of treatment methods by creating computer models of the...
Show moreThis paper describes how a force response equation was created to model muscles, tendons, and ligaments of the hip joint to improve a biomechanical model of an infant hip to study Developmental Dysplasia of the Hip (DDH). DDH is the most common abnormality in newborn infants and is defined as any amount of instability in the hip including complete dislocation. Researchers at our institution are attempting to increase the success rate of treatment methods by creating computer models of the biomechanics of infant hip instability and dislocation. The computer model used a scaled adult pelvis, femur, tibia, fibula and foot to match the size of an infant for the bone geometry. The current infant muscle model is an undifferentiated model based on the area of a single infant muscle, for all muscles modeled. This muscle model was able to provide some insight into the nature of the biomechanics. To improve the infant muscle model, a set of equations differentiated by muscle area was developed. The new set of equations uses a ratio of infant over adult muscle area of a single muscle to create a ratio that can be used to scale all adult muscle areas to infant areas. This model will be more physiologically accurate because it will be differentiated based on muscle area.
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Date Issued
2015
Identifier
CFH0004896, ucf:45421
Format
Document (PDF)
PURL
http://purl.flvc.org/ucf/fd/CFH0004896
Ultrasound Measured Flexor Muscle Thickness in the Forearms of Rock Climbers
Title
Ultrasound Measured Flexor Muscle Thickness in the Forearms of Rock Climbers.
Creator
Marsala, Michael, Garcia, Jeanette, Fukuda, David, Stock, Matt, University of Central Florida
Abstract / Description
PURPOSE: To examine differences in the forearms of rock climbers using ultrasound to measure the muscle thickness of the finger flexors. METHODS: A total of 33 participants were recruited, 22 climbers (22.23 years; 68% male) and 11 controls (21.8; 55% male). Climbers provided self-reported ratings of their climbing ability, skill level, and preferred mode of climbing (e.g. sport climbing vs. bouldering). Anthropometric measures, including body fat percentage, were measured in all participants...
Show morePURPOSE: To examine differences in the forearms of rock climbers using ultrasound to measure the muscle thickness of the finger flexors. METHODS: A total of 33 participants were recruited, 22 climbers (22.23 years; 68% male) and 11 controls (21.8; 55% male). Climbers provided self-reported ratings of their climbing ability, skill level, and preferred mode of climbing (e.g. sport climbing vs. bouldering). Anthropometric measures, including body fat percentage, were measured in all participants. Ultrasound measurements were taken with the participant lying on their back on a padded table with their dominant hand supinated. Muscle thickness measurements were taken at the forearm where a peak of the forearm flexors was identified on the medial aspect of the forearm after a circumference measurement and small mark was made. The distance from the ulna and radius to the muscle-skin interface was measured, as well as echo intensity surrounding the median nerve using a third party program. RESULTS: Approximately 50% of climbers rated themselves as (")intermediate("), and the other 50% rated themselves as (")advanced(") climbers, while 77% of the 22 climbers classified themselves as primarily (")sport climbers("), and 23% classified themselves as (")boulderers("). Body fat percentages were significantly different at 19.14(&)#177;6.99 and 30.02(&)#177;7.6 for climbers and controls. Ulnar and radial muscle thickness values were significantly higher in climbers, 4.23(&)#177;.39and 2.32(&)#177;.39, respectively, and 3.61(&)#177;.6 and 1.84(&)#177;.31 in controls (p(<).001). No differences in echo intensity were observed between climbers and non-climbers. DISCUSSION: The findings suggests that there are differences in flexor muscle thickness observed in earlier stages of rock climbing. Echo intensity of the flexor muscles were also measured, however significant variance in results warrants further investigation. Future studies should consider larger samples to better determine differences among muscle thickness and echo intensity across climbing abilities and mode of climbing, thus allowing for more specific training programs to be developed at each phase of training.
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Date Issued
2019
Identifier
CFE0007677, ucf:52473
Format
Document (PDF)
PURL
http://purl.flvc.org/ucf/fd/CFE0007677
Do Changes in Muscle Architecture Effect Post- Activation Potentiation
Title
Do Changes in Muscle Architecture Effect Post- Activation Potentiation.
Creator
Reardon, Danielle, Hoffman, Jay, Fragala, Maren, Stout, Jeffrey, Fukuda, David, University of Central Florida
Abstract / Description
Purpose: To examine the effect of three muscle potentiation protocols on changes in muscle architecture and the subsequent effect on jump power performance. Methods: Maximal (1RM) squat strength (Mean SD=178.3 (&)#177; 36.6kg), vertical jump power, and muscle architecture were obtained in 12 resistance trained men (25.2(&)#177;3.6y; 90.67(&)#177;12.7kg). Participants randomly completed three squatting protocols at 75% (3 x 10 reps), 90% (3 x 3 reps) or 100% (1 x 1) of their 1RM, or no workout...
Show morePurpose: To examine the effect of three muscle potentiation protocols on changes in muscle architecture and the subsequent effect on jump power performance. Methods: Maximal (1RM) squat strength (Mean SD=178.3 (&)#177; 36.6kg), vertical jump power, and muscle architecture were obtained in 12 resistance trained men (25.2(&)#177;3.6y; 90.67(&)#177;12.7kg). Participants randomly completed three squatting protocols at 75% (3 x 10 reps), 90% (3 x 3 reps) or 100% (1 x 1) of their 1RM, or no workout (CON), with each protocol being separated by one week. During each testing session ultrasound and vertical jump testing were assessed at baseline (BL), 8min post (8P) and 20min post (20P) workout. Ultrasound measures of the rectus femoris (RF) and vastus lateralis (VL) muscles included; cross sectional area (CSA) and pennation angle (PNG). Following each ultrasound, peak (PVJP) and mean (MVJP) vertical jump power (using hands for maximum jump height) were measured using an accelerometer. Results: Magnitude based inferences analysis indicated that in comparison to CON, 75% resulted in a likely greater change in RF-CSA and VL-CSA (BL-8P and BL(-)20P), 90% resulted in a likely greater RF-CSA and VL-CSA (BL(-)20P), and 100% resulted in a very likely or likely decrease in VL-PNG at BL-8P and BL(-)20P, respectively). Meanwhile, changes in PVJP and MVJP for the 75% trial was likely decreased at BL-8P and BL(-)20P; and for the 90% trial MVJP was likely decreased at BL-8P and BL(-)20P. Analysis of the magnitude of the relationships indicated a likely negative relationship between VL-PNG and MVJP (r = -0.35; p (<) 0.018) at BL-8P, while at BL(-)20P, a negative relationship was observed between PVJP and RF-CSA (r = -0.37; p (<) 0.014). Conclusion: Acute increases in muscle size and acute decreases in pennation angle did not result in any potentiation in vertical jump power measures. Although the inverse relationships observed between muscle architecture variables and power suggests a potential effect, the change in position (i.e. movement from standing to supine for ultrasound measures) may negate, as a result of potential fluid shifts or muscle relaxation, the potentiating effects of the exercise. It is also possible that the fatiguing nature of the squat protocols in trained but not competitive participants may have also contributed to the results.
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Date Issued
2013
Identifier
CFE0005048, ucf:49963
Format
Document (PDF)
PURL
http://purl.flvc.org/ucf/fd/CFE0005048
Physiological Muscle Qualitative Changes in Response to Resistance Training in Older Adults
Title
Physiological Muscle Qualitative Changes in Response to Resistance Training in Older Adults.
Creator
Scanlon, Tyler, Fragala, Maren, Hoffman, Jay, Stout, Jeffrey, University of Central Florida
Abstract / Description
Muscle function is determined by structure and morphology at the architectural level. In response to resistance training, older adults have demonstrated that the neuromuscular system has a substantial adaptability, which may compensate for muscle size and quality and lead to improved functional capacities and higher quality of life. PURPOSE: The purpose of this study was to examine the effect of six weeks of progressive resistance exercise on muscle morphology and architecture in healthy...
Show moreMuscle function is determined by structure and morphology at the architectural level. In response to resistance training, older adults have demonstrated that the neuromuscular system has a substantial adaptability, which may compensate for muscle size and quality and lead to improved functional capacities and higher quality of life. PURPOSE: The purpose of this study was to examine the effect of six weeks of progressive resistance exercise on muscle morphology and architecture in healthy older adults. METHODS: Twenty- five healthy men and women were randomly assigned to either six weeks of progressive resistance training (RT) (n=13; age = 71.08 (&)#177; 6.75, BMI = 28.5 (&)#177; 5.22) or to serve as a control (CON) (n = 12; age = 70.17 (&)#177; 5.58, BMI = 27.52 (&)#177; 5.6). Fat mass (FM), lean mass (LM), and lean thigh mass (LTM) were evaluated using dual x-ray absorptiometry. Lower body strength was estimated by predicting maximal knee extensor strength (1RM). Muscle quality (MQ) was evaluated as strength per unit mass (kg/kg). Cross-sectional area (CSA), muscle thickness (MT), fascicle length (Lf), pennation angle (cos?), and echo intensity (EI) of the rectus femoris (RF) and vastus lateralis (VL) were collected using B-mode ultrasound and extended field of view (FOV) ultrasound. EI was quantified using grayscale analysis software. Strength per unit of echo intensity (REI) was determined by dividing 1RM by EI of the thigh. Physiological cross-sectional area (PCSA) was calculated as the ratio of (CSA x cos?) / (EI x Lf). A 2x2 (group [exercise vs. control] x time [pre vs. post]) repeated measures ANOVA was used to identify group differences and group x time interactions and stepwise regression was performed to assess variables related to strength. RESULTS: 1RM increased by 31.9% (p ? 0.01) in the RT group and was significantly correlated to PCSA of the thigh (r = .579; p = .003) at baseline. MQ increased 31.4% (p ? 0.01) in the RT group consistent with an REI increase of 33.3% (p ? 0.01). There were no significant changes in LTM in either group. VL CSA increased 7.4%, (p ? 0.05) and demonstrated a significant interaction (p ? 0.05) in the RT group. There were no significant changes in the CON group for 1RM, MQ, REI or VL CSA. PCSA demonstrated a significant (p ? 0.05) group x time interaction but did not significantly change in either group. EI did not significantly change in the RT or CON groups. CONCLUSION: Calculated PCSA of the thigh assessed by ultrasound was related to the force producing capacity of muscle and demonstrated a significant interaction following resistance training. Short term resistance exercise training was effective in increasing 1RM, muscle quality as relative strength, muscle quality as relative echo intensity, and muscle morphology, but not EI. In addition, ultrasonography appears to be a safe, feasible, informative and sensitive clinical technique to aid in our understanding of muscle strength, function, and quality.
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Date Issued
2013
Identifier
CFE0004748, ucf:49782
Format
Document (PDF)
PURL
http://purl.flvc.org/ucf/fd/CFE0004748
Biomechanics of Developmental Dysplasia of the Hip - An engineering study of closed reduction utilizing the Pavlik harness for a range of subtle to severe dislocations in infants.
Title
Biomechanics of Developmental Dysplasia of the Hip - An engineering study of closed reduction utilizing the Pavlik harness for a range of subtle to severe dislocations in infants.
Creator
Huayamave, Victor, Divo, Eduardo, Kassab, Alain, Reddi, Lakshmi, University of Central Florida
Abstract / Description
Developmental Dysplasia of the Hip (DDH) is an abnormal condition where hip joint dislocation, misalignment, or instability is present in infants. Rates of incidence of DDH in newborn infants have been reported to vary between 1 and 20 per 1000 births, making it the most common congenital malformation of the musculoskeletal system. DDH early detection and treatment is critical to avoid the use of surgical treatment in infants and to prevent future complications such as osteoarthritis in adult...
Show moreDevelopmental Dysplasia of the Hip (DDH) is an abnormal condition where hip joint dislocation, misalignment, or instability is present in infants. Rates of incidence of DDH in newborn infants have been reported to vary between 1 and 20 per 1000 births, making it the most common congenital malformation of the musculoskeletal system. DDH early detection and treatment is critical to avoid the use of surgical treatment in infants and to prevent future complications such as osteoarthritis in adult life. To this day several non-surgical treatments involving the use of harnesses and braces have been proposed to treat DDH in infants, with the Pavlik harness being the current non-surgical standard used to treat DDH at early stages. Although the Pavlik harness has been proven to be successful treating subtle dislocations, severe dislocations do not always reduce. Until now the use of the harness remains an empirical method, and its effectiveness often depends on physician expertise or trial-error procedures; thus a clear guideline has not been established to determine the best optimal harness configuration to treat both subtle and severe dislocations. The goal of this dissertation is to understand the connection between reductions for subtle and severe dislocations and passive muscle forces and moments generated while the harness is used during treatment. While the understanding of DDH biomechanics will provide a valuable clinically applicable approach to optimize and increase harness success rate, it is not without its difficulties. This research has created and developed a three-dimensional based on patient-specific geometry of an infant lower limb. The kinematics and dynamics of the lower limb were defined by modeling the hip, femur, tibia, fibula, ankle, foot, and toe bones. The lines of action of five (5) adductor muscles, namely, the Adductor Brevis, Adductor Longus, Adductor Magnus, Pectineus, and Gracilis were identified as mediators of reduction and its mechanical behavior was characterized using a passive response. Four grades (1-4) of dislocation as specified by the International Hip Dysplasia Institute (IHDI) were considered, and the computer model was computationally manipulated to represent physiological dislocations. To account for proper harness modeling, the femur was restrained to move in an envelope consistent with its constraints. The model of the infant lower limb has been used to analyze subtle and severe dislocations. Results are consistent with previous studies based on a simplified anatomically-consistent synthetic model and clinical reports of very low success of the Pavlik harness for severe dislocations. Furthermore the findings on this work suggest that for severe dislocations, the use of the harness could be optimized to achieve hyperflexion of the lower limb leading to successful reduction for cases where the harness fails.This approach provides three main advantages and innovations: 1) the used of patient-specific geometry to elucidate the biomechanics of DDH; 2) the ability to computationally dislocate the model to represent dislocation severity; and 3) the quantification of external forces needed to accomplish reduction for severe dislocations. This study aims to offer a practical solution to effective treatment that draws from engineering expertise and modeling capabilities and also draws upon medical input. The findings of this work will lay the foundation for future optimization of non-surgical methods critical for the treatment of DDH.
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Date Issued
2015
Identifier
CFE0005631, ucf:50216
Format
Document (PDF)
PURL
http://purl.flvc.org/ucf/fd/CFE0005631
Embryonic Stem Cell-Derived Exosomes Inhibit Doxorubicin-Induced Pyroptosis in Cell Culture Models
Title
Embryonic Stem Cell-Derived Exosomes Inhibit Doxorubicin-Induced Pyroptosis in Cell Culture Models.
Creator
Tavakoli Dargani, Zahra, Singla, Dinender, Masternak, Michal, Siddiqi, Shadab, Steward, Robert, University of Central Florida
Abstract / Description
Doxorubicin (Dox) is a potent chemotherapeutic drug used for the treatment of various cancers. Unfortunately, its use is limited as Dox induces adverse cardiotoxicity (DIC) and muscle toxicity (DIMT), which are mediated through oxidative stress, ER stress, and inflammation. However, it remains unknown whether Dox induces an inflammation mediated cell death, called (")pyroptosis("). The current study is designed to determine whether Dox induces pyroptosis in cardiac and muscle cell culture...
Show moreDoxorubicin (Dox) is a potent chemotherapeutic drug used for the treatment of various cancers. Unfortunately, its use is limited as Dox induces adverse cardiotoxicity (DIC) and muscle toxicity (DIMT), which are mediated through oxidative stress, ER stress, and inflammation. However, it remains unknown whether Dox induces an inflammation mediated cell death, called (")pyroptosis("). The current study is designed to determine whether Dox induces pyroptosis in cardiac and muscle cell culture models. Moreover, the protective effects of embryonic stem cell-derived exosomes (ES-Exos) in inhibiting pyroptosis will also be determined. For this purpose, we designed two different cell culture models using H9c2 cadiomyoblasts and Sol 8 cells. For the DIC model, H9c2 were exposed to Dox to induce pyroptosis and then treated with exosomes. Cells were divided into 4 groups: Control, Dox, Dox+ES-Exos, and Dox+MEF-Exos (negative control). Furthermore, to generate the DIMT model, Sol 8 cells were incubated with Dox+THP-1 conditioned medium (TCM) to induce toxicity and inflammation, which was followed by exosomes treatment. We assigned cells into 5 groups: Control, Dox+TCM, Dox+TCM+ES-Exos, Dox+TCM+MEF-Exos (negative control), and Dox+TCM+ES-Exos+GW4869 compound (exosomes inhibitor, negative control). Our data shows that Dox treatment significantly increased pyroptotic marker expression including TLR-4, NLRP3, caspase-1, IL1-?, Caspase-11, and gasdermin-D as well as increased pro-inflammatory TNF-? and IL-6 expression in H9c2 cells. There was also a significant increase in caspase-1, IL1-?, and IL-18 expression in Dox+TCM treated Sol 8 cells. Conversely, increased pyroptosis and inflammation post-Dox treatment were inhibited by ES-Exos in both culture models. No significant changes observed upon MEF-Exos and GW4869 compound treatments. In conclusion, our data shows Dox induces pyroptosis and inflammation within cardiac and skeletal muscle cells, which can be inhibited following treatment with ES-exosomes. This is a novel study with new mechanistic observations on the pathophysiological role of pyroptosis in Dox-induced cardio and muscle toxicities.
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Date Issued
2018
Identifier
CFE0007416, ucf:52700
Format
Document (PDF)
PURL
http://purl.flvc.org/ucf/fd/CFE0007416
Effects of an Acute High-Volume Isokinetic Intervention on Inflammatory and Strength Changes: Influence of Age
Title
Effects of an Acute High-Volume Isokinetic Intervention on Inflammatory and Strength Changes: Influence of Age.
Creator
Gordon, Joseph, Hoffman, Jay, Stout, Jeffrey, Fukuda, David, University of Central Florida
Abstract / Description
PURPOSE: The purpose of this study was to compare the effects of a high volume isokinetic intervention on lower body strength and inflammation, as well as markers of muscle damage in the subsequent 48 hours between younger and middle-aged men. METHODS: 19 healthy, recreationally trained men were randomly assigned to two groups, younger adults (YA: 21.8 (&)#177; 2.0 y; 90.7 (&)#177; 11.6 kg; 21.5 (&)#177; 4.1 % body fat), or middle-aged adults (MA: 47.0 (&)#177; 4.4 y; 96.0 (&)#177; 21.5; 24.8...
Show morePURPOSE: The purpose of this study was to compare the effects of a high volume isokinetic intervention on lower body strength and inflammation, as well as markers of muscle damage in the subsequent 48 hours between younger and middle-aged men. METHODS: 19 healthy, recreationally trained men were randomly assigned to two groups, younger adults (YA: 21.8 (&)#177; 2.0 y; 90.7 (&)#177; 11.6 kg; 21.5 (&)#177; 4.1 % body fat), or middle-aged adults (MA: 47.0 (&)#177; 4.4 y; 96.0 (&)#177; 21.5; 24.8 (&)#177; 6.3 % body fat). Both groups reported to the human performance laboratory (HPL) on four separate occasions. On the first visit (D1), anthropometric assessment, as well as a familiarization session with the isokinetic dynamometer, was performed. A muscle damaging protocol (HVP) was performed on the second visit (D2) consisting of 8 sets of 10 repetitions at 60(&)deg;(&)#183;sec-1 on the isokinetic dynamometer. An assessment protocol (AP) was performed to assess performance decrements between the YA and MA groups. For this protocol, a maximal voluntary isometric contraction (MVIC) was performed, as well as 3 isokinetic kicks at 2 different speeds (240(&)deg;(&)#183;sec-1 and 60(&)deg;(&)#183;sec-1). For the MVIC, values for peak torque (PKT), average torque (AVGT), rate of torque development at 100 ms (RTD100), and 200 ms (RTD200) were recorded. For the isokinetic kicks at 240(&)deg;(&)#183;sec-1 (ISK240) and 60(&)deg;(&)#183;sec-1 (ISK60), values were also recorded for peak torque (PKT), average torque (AVGT), as well as peak power (PP), and average power (AVGP). The AP was performed before the HVP (BL), immediately after the HVP (IP), 120 minutes after the HVP (120P), as well as one (24H) and two (48H) days following the HVP. Blood draws were also taken at BL, IP, 24H, and 48H, as well as 30 minutes (30P), and 60 minutes (60P) following the HVP to assess circulating levels of creatine kinase (CK), myoglobin (Mb), c-reactive protein (CRP), and interleukin 6 (IL-6). Ultrasound assessment was also performed at BL and IP as well to assess changes in muscle morphology as a result of the intervention. Performance, blood, and ultrasound markers were analyzed using a repeated measures ANOVA to observe between group comparisons for all of the outcome variables. RESULTS: There were no group differences observed for isometric or isokinetic peak torque or average torque, nor were there differences in isokinetic peak power or average power between the two groups as a result of the intervention. There were, however, differences in the pattern for rate of torque development at 100 ms and 200 ms between the two groups. RTD 100 was decreased at IP and 48H in YA, with MA showing decreases at IP, but also 120P and 24H unlike YA. RTD200 was decreased at all time points in YA, while MA was decreased at IP, 24H, and 48H, but not 120P. For markers of muscle damage and inflammation, there were no differences in the response of Mb, CK, CRP, or IL-6 between groups. CONCLUSIONS: Age does not appear to be a driving factor in the inflammatory or muscle damage response from a high volume isokinetic intervention. Though changes in peak torque and average torque from a high volume isokinetic intervention do not seem to differ between younger and middle-aged adults, the rate of torque production at 100ms and 200ms is different between groups. This suggests that while recovery to average or maximal strength after an exercise bout may not be affected greatly by age, the rate of neuromuscular recovery from exercise may be primarily affected by other factors such as training status.
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Date Issued
2017
Identifier
CFE0006594, ucf:51259
Format
Document (PDF)
PURL
http://purl.flvc.org/ucf/fd/CFE0006594
The effect of training volume and intensity on improvements in muscular strength and size in resistance-trained men
Title
The effect of training volume and intensity on improvements in muscular strength and size in resistance-trained men.
Creator
Mangine, Gerald, Hoffman, Jay, Fukuda, David, Stout, Jeffrey, Ratamess, Nicholas, University of Central Florida
Abstract / Description
The magnitude of improvements in muscular strength and size are influenced by the volume and intensity of a resistance training program. While it is clearly advantageous for resistance-trained individuals to utilize programming specific to these goals, it not clear which is more important. Therefore the purpose of the present investigation was to determine the effect of focusing on training volume versus intensity on changes in muscle size and strength. Changes in muscular strength and size...
Show moreThe magnitude of improvements in muscular strength and size are influenced by the volume and intensity of a resistance training program. While it is clearly advantageous for resistance-trained individuals to utilize programming specific to these goals, it not clear which is more important. Therefore the purpose of the present investigation was to determine the effect of focusing on training volume versus intensity on changes in muscle size and strength. Changes in muscular strength and size were examined in 29 resistance-trained men following 8 weeks of resistance training. Participants were randomly assigned to either a high volume (VOL, n = 14, 4 x 10 (-) 12RM, 1min rest) or high intensity (INT, n = 15, 4 x 3 (-) 5RM, 3min rest) resistance training program. Lean body mass, lean arm and leg mass, were assessed by dual energy X-ray absorptiometry, while ultrasound images (VL-vastus lateralis, RF-rectus femoris, PM-pectoralis major, and TB-triceps brachii) were used to assess changes in muscle cross-sectional area (CSA) and thickness (MT). Strength was measured by one repetition-maximum (1RM) squat (SQ) and bench press (BP). Changes in muscular (RF (&) VL) activation in response to increases in submaximal SQ intensity (40-, 60-, 80-, (&) 100%-1RM) were assessed via surface electromyography. Blood samples were collected at baseline, immediately post, 30min post, and 60min post-exercise at week 3 (WK3) and week 10 (WK10), to assess plasma/serum testosterone, growth hormone (GH), insulin-like growth factor-1 (IGF1), cortisol (CORT), and insulin. Area under the curve analysis revealed a greater (p (<) 0.05) increase for VOL (WK3: GH (&) CORT; WK10: CORT) compared to INT. Compared to WK3, WK10 showed reduced responses for VOL (GH and CORT) and INT (IGF1). Significant group differences were observed for changes in lean arm mass (INT: 5.2 (&)#177; 2.9%, VOL: 2.2 (&)#177; 5.6%) and BP 1RM (INT: 14.8 (&)#177; 9.7%, VOL: 6.9 (&)#177; 9.0%). Over the course of 8 weeks, our data indicate that trained men would benefit more when focusing on training intensity, rather than volume, for strength and size improvements.
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Date Issued
2015
Identifier
CFE0005658, ucf:50179
Format
Document (PDF)
PURL
http://purl.flvc.org/ucf/fd/CFE0005658
Effects of Rest Position on Ultrasound-Derived Morphological Characteristics of the Vastus Lateralis and Lower-Body Force Production
Title
Effects of Rest Position on Ultrasound-Derived Morphological Characteristics of the Vastus Lateralis and Lower-Body Force Production.
Creator
Varanoske, Alyssa, Wells, Adam, Fukuda, David, Stout, Jeffrey, Mangine, Gerald, University of Central Florida
Abstract / Description
INTRODUCTION: Ultrasound assessment of the lower body typically encompasses 10-15 minutes of supine rest prior to examination because of the potential influence of gravitational fluid shifts on tissue size and composition. However, examination of the vastus lateralis (VL) muscle requires individuals to lay in the lateral recumbent position, and this change in position may influence muscle morphological characteristics and their ability to predict muscle function.PURPOSE: The purpose of this...
Show moreINTRODUCTION: Ultrasound assessment of the lower body typically encompasses 10-15 minutes of supine rest prior to examination because of the potential influence of gravitational fluid shifts on tissue size and composition. However, examination of the vastus lateralis (VL) muscle requires individuals to lay in the lateral recumbent position, and this change in position may influence muscle morphological characteristics and their ability to predict muscle function.PURPOSE: The purpose of this investigation was to examine the effect of rest position on ultrasound-derived morphological characteristics of the VL and to determine whether or not rest position affects the relationships between muscle morphological characteristics of the VL and lower-body force and power production. METHODS: Thirty-one resistance-trained males (age: 23.0 (&)#177; 2.1 years; height: 1.79 (&)#177; 0.08 m; body mass: 87.4 (&)#177; 11.7 kg) participated in this investigation. Muscle morphological characteristics, including cross-sectional area (CSA), muscle thickness (MT), pennation angle (PA), echo intensity (UnCorEI), subcutaneous adipose tissue thickness (SFT), and EI corrected for SFT (CorEI) of the VL were assessed in the dominant limb after 15 minutes of rest in 3 recumbent positions: supine (SUP), dominant lateral recumbent (DLR), non-dominant lateral recumbent (NDLR), as well as after 15 minutes of standing (ST) and immediately after laying down (IP). Following ultrasound assessments, participants completed unilateral performance assessments, including vertical jumps (UVJ), isometric/isokinetic testing, and a 1-repetition maximum (1-RM) leg press. RESULTS: A repeated-measures analysis of variance revealed significantly different (p (<) 0.05) CSA, MT, PA, UnCorEI, and SFT in ST compared to recumbent positions after 15 minutes of rest (NDLR, DLR, and SUP). Additionally, significant differences were observed between recumbent positions for CSA, CorEI, and UnCorEI; however, no differences were observed for MT, PA, and SFT. Different magnitudes of relationships were observed between muscle morphological characteristics measured after rest in different positions and performance variables. However, muscle morphology after IP generally appears to be the best predictor of performance for most variables, although utilizing the NDLR and DLR positions may provide comparable, or potentially stronger results for variables such as IsokPF. The relationship between muscle morphology and various performance variables in ST were weaker compared to the recumbent positions examined, specifically for IsokPF, 1-RM leg press, and for all UVJ variables, except total work.CONCLUSIONS: Muscle morphology differs depending on the rest position utilized prior to ultrasound analysis. These rest positions also affect the ability for muscle morphology to predict lower-body force production. Future research should consider evaluation of muscle morphology of the VL after IP in the prediction of muscle function; however, NDLR and DLR may also be used. SUP and ST provide significantly weaker relationships for some performance variables compared to the other recumbent positions.
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Date Issued
2019
Identifier
CFE0007550, ucf:52610
Format
Document (PDF)
PURL
http://purl.flvc.org/ucf/fd/CFE0007550
PELVIC FLOOR MUSCLE TRAINING IN MANAGEMENT OF POSTPARTUM PELVIC FLOOR DYSFUNCTIONS: A LITERATURE REVIEW
Title
PELVIC FLOOR MUSCLE TRAINING IN MANAGEMENT OF POSTPARTUM PELVIC FLOOR DYSFUNCTIONS: A LITERATURE REVIEW.
Creator
Tanner, Rebecca S, Rothschild, Carey, University of Central Florida
Abstract / Description
Women can face a wide range of pelvic floor dysfunctions following pregnancy, ranging from urinary incontinence to pelvic pain. Unfortunately, these problems are not routinely checked for in postpartum check-ups and women do not always bring it to the physician's attention. Strengthening of the pelvic floor muscles may be able to help women prevent these disorders and improve these women's lifestyles. The purpose of this thesis was to review and analyze different trials to determine if...
Show moreWomen can face a wide range of pelvic floor dysfunctions following pregnancy, ranging from urinary incontinence to pelvic pain. Unfortunately, these problems are not routinely checked for in postpartum check-ups and women do not always bring it to the physician's attention. Strengthening of the pelvic floor muscles may be able to help women prevent these disorders and improve these women's lifestyles. The purpose of this thesis was to review and analyze different trials to determine if different pelvic floor dysfunctions (urinary incontinence, sexual dysfunction, and pelvic girdle pain) can be treated using pelvic floor muscle training in the postpartum. After reviewing the literature, it was determined that Pelvic floor muscle training may be effective in treating Urinary incontinence, but there is a lack of research to state that it helps treat sexual dysfunction and pelvic pain. Pelvic floor muscle training is a conservative non-invasive treatment and very simple for women to do on their own, therefore more research should be performed to see if this can be a simple fix to a plethora of problems women face in the postpartum.
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Date Issued
2016
Identifier
CFH2000110, ucf:46052
Format
Document (PDF)
PURL
http://purl.flvc.org/ucf/fd/CFH2000110
EXAMINATION OF THE REHABILITATION PROTOCOL OF TRAUMATIC TRANSFEMORAL AMPUTEES AND HOW TO PREVENT BONE MINERAL DENSITY LOSS
Title
EXAMINATION OF THE REHABILITATION PROTOCOL OF TRAUMATIC TRANSFEMORAL AMPUTEES AND HOW TO PREVENT BONE MINERAL DENSITY LOSS.
Creator
Jenkinson, Emily R, Fisher, Thomas, University of Central Florida
Abstract / Description
The purpose of this literature review was to identify any adaptations that could be made to the rehabilitation process for Traumatic Transfemoral Amputees. Traumatic Transfemoral Amputation is particularly debilitating with the amputees encountering many obstacles throughout the rehabilitation process. These obstacles can prevent the return to pre-morbid functioning. With an ever-increasing number of amputees within the United States, it is imperative the rehabilitation process be addressed....
Show moreThe purpose of this literature review was to identify any adaptations that could be made to the rehabilitation process for Traumatic Transfemoral Amputees. Traumatic Transfemoral Amputation is particularly debilitating with the amputees encountering many obstacles throughout the rehabilitation process. These obstacles can prevent the return to pre-morbid functioning. With an ever-increasing number of amputees within the United States, it is imperative the rehabilitation process be addressed. This literature review addresses possible adjustments in the initial stages of rehabilitation examining the post-operative, pre-prosthetic, and prosthetic rehabilitation stage to enhance the physical functioning for the amputee. This comprehensive literature review encompassing 63 academic and medical journals analyzes the research literature regarding each of the three stages of the post-operative procedure. The literature review synthesizes the research findings to see how procedures may be adapted to reduce the risk of further co-morbidities such as loss of bone mineral density and disuse atrophy. Loss of bone mineral density and disuse atrophy are the major contributing factors to the amputees decreased mobility. Reducing this loss can be addressed within the initial post-operative, pre-prosthetic, and prosthetic rehabilitation stages. Further research is required to examine the efficacy of these alterations in relation to this specific population.
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Date Issued
2017
Identifier
CFH2000268, ucf:45964
Format
Document (PDF)
PURL
http://purl.flvc.org/ucf/fd/CFH2000268
SPORTS MASSAGE RESEARCH PROTOCOLS AND INDUSTRY STANDARDS
Title
SPORTS MASSAGE RESEARCH PROTOCOLS AND INDUSTRY STANDARDS.
Creator
Kest, Amber, Valdes, Anna, University of Central Florida
Abstract / Description
The purpose of this study was to determine which MT techniques current licensed massage therapists practicing sports massage are using to treat delayed onset muscle soreness (DOMS) by conducting an anonymous online survey of practicing sports massage therapists. The secondary purpose was to determine if previous sports massage research protocols match current practices in sports massage to treat DOMS. There were 85 anonymous respondents ranging in age from 24 to 74 years with a mean age of 44...
Show moreThe purpose of this study was to determine which MT techniques current licensed massage therapists practicing sports massage are using to treat delayed onset muscle soreness (DOMS) by conducting an anonymous online survey of practicing sports massage therapists. The secondary purpose was to determine if previous sports massage research protocols match current practices in sports massage to treat DOMS. There were 85 anonymous respondents ranging in age from 24 to 74 years with a mean age of 44.5 years. Participants included 55 female (65.5%) and 29 male (34.5%) therapists. Professional experience ranged from 4 years or less to more than 20 years, and the majority reported having training specific to sports massage. Previous research methods have placed an overwhelming emphasis on effleurage and petrissage in the treatment protocols to test the effects of massage on DOMS. However, practicing therapists rely on many more techniques and modalities when giving sports massage treatments for DOMS. On a scale of 1 to 5 respondents rated the importance of effleurage strokes in their sports massage treatment at 3.3, petrissage strokes averaged 3.4, friction 3.3, and tapotement ranked slightly lower with a weighted average of 2.1. Sixty six percent of respondents reported that they use stretching techniques often or always. Myofascial release techniques are used sometimes or often for 65% of the respondents, but fewer utilize manual lymphatic drainage in their sports massage. Additional techniques besides those mentioned in the survey are used by 64% of the respondents.
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Date Issued
2015
Identifier
CFH0004846, ucf:45476
Format
Document (PDF)
PURL
http://purl.flvc.org/ucf/fd/CFH0004846
Mechanism of Hip Dysplasia and Identification of the Least Energy Path for its Treatment by using the Principle of Stationary Potential Energy
Title
Mechanism of Hip Dysplasia and Identification of the Least Energy Path for its Treatment by using the Principle of Stationary Potential Energy.
Creator
Zwawi, Mohammed abdulwahab m, Moslehy, Faissal, Kassab, Alain, Mansy, Hansen, Divo, Eduardo, University of Central Florida
Abstract / Description
Developmental dysplasia of the hip (DDH) is a common newborn condition where the femoral head is not located in its natural position in the acetabulum (hip socket). Several treatment methods are being implemented worldwide to treat this abnormal condition. One of the most effective methods of treatment is the use of Pavlik Harness, which directs the femoral head toward the natural position inside the acetabulum. This dissertation presents a developed method for identifying the least energy...
Show moreDevelopmental dysplasia of the hip (DDH) is a common newborn condition where the femoral head is not located in its natural position in the acetabulum (hip socket). Several treatment methods are being implemented worldwide to treat this abnormal condition. One of the most effective methods of treatment is the use of Pavlik Harness, which directs the femoral head toward the natural position inside the acetabulum. This dissertation presents a developed method for identifying the least energy path that the femoral head would follow during reduction. This is achieved by utilizing a validated computational biomechanical model that allows the determination of the potential energy, and then implementing the principle of stationary potential energy. The potential energy stems from strain energy stored in the muscles and gravitational potential energy of four rigid-body components of lower limb bones. Five muscles are identified and modeled because of their effect on DDH reduction. Clinical observations indicate that reduction with the Pavlik Harness occurs passively in deep sleep under the combined effects of gravity and the constraints of the Pavlik Harness.A non-linear constitutive equation, describing the passive muscle response, is used in the potential energy computation. Different DDH abnormalities with various flexion, abduction, and hip rotation angles are considered, and least energy paths are identified. Several constraints, such as geometry and harness configuration, are considered to closely simulate real cases of DDH. Results confirm the clinical observations of two different pathways for closed reduction. The path of least energy closely approximated the modified Hoffman-Daimler method. Release of the pectineus muscle favored a more direct pathway over the posterior rim of the acetabulum. The direct path over the posterior rim of the acetabulum requires more energy. This model supports the observation that Grade IV dislocations may require manual reduction by the direct path. However, the indirect path requires less energy and may be an alternative to direct manual reduction of Grade IV infantile hip dislocations. Of great importance, as a result of this work, identifying the minimum energy path that the femoral head would travel would provide a non-surgical tool that effectively aids the surgeon in treating DDH.?
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Date Issued
2015
Identifier
CFE0006022, ucf:51000
Format
Document (PDF)
PURL
http://purl.flvc.org/ucf/fd/CFE0006022
Resistance Exercise Elicits Selective Mobilization and Adhesion Characteristics of Granulocytes and Monocyte Subsets
Title
Resistance Exercise Elicits Selective Mobilization and Adhesion Characteristics of Granulocytes and Monocyte Subsets.
Creator
Jajtner, Adam, Hoffman, Jay, Stout, Jeffrey, Fukuda, David, Radom-Aizik, Shlomit, University of Central Florida
Abstract / Description
Resistance exercise eliciting muscle damage results in an immune response, leading to increases in circulating cytokines, and immune cell mobilization. Classical monocytes respond to muscle damage, however, little is known about the intermediate or nonclassical monocyte response to resistance exercise. Moreover, the impact of polyphenol supplementation in conjunction with resistance exercise on the innate immune response is unknown. The purpose of this study was to examine the immune response...
Show moreResistance exercise eliciting muscle damage results in an immune response, leading to increases in circulating cytokines, and immune cell mobilization. Classical monocytes respond to muscle damage, however, little is known about the intermediate or nonclassical monocyte response to resistance exercise. Moreover, the impact of polyphenol supplementation in conjunction with resistance exercise on the innate immune response is unknown. The purpose of this study was to examine the immune response following resistance exercise with (PPB) and without (PL) polyphenol supplementation. Thirty-nine untrained men were randomized into three groups: PPB (n=13, 21.8(&)#177;2.5yrs, 171.2(&)#177;5.5cm, 71.2(&)#177;8.2kg), PL (n=15, 21.6(&)#177;2.5yrs, 176.5(&)#177;4.9cm, 84.0(&)#177;15.7kg) or a control group (CON) (23.3(&)#177;4.1yrs, 173.6(&)#177;12.0cm, 77.8(&)#177;15.6kg). Blood samples were obtained pre- (PRE), immediately- (IP), 1- (1H), 5- (5H), 24- (24H), 48- (48H) and 96- (96H) hours post-exercise (PPB/PL). CON rested for one hour between PRE and IP blood draws. Changes in granulocyte and monocyte subset proportions and adhesion characteristics (CD11b) were assessed via flow cytometry, while plasma cytokine concentrations and markers of muscle damage were analyzed via multiplex and spectrophotometric assays, respectively. Creatine Kinase and myoglobin were elevated at each time point for PPB and PL (p (<) 0.050). Monocyte chemoattractant protein-1 was significantly elevated at IP in PPB (p = 0.005) and PL (p = 0.006) and significantly greater than CON at 5H (PPB: p (<) 0.001; PL: p = 0.006). Granulocyte proportions were elevated at 1H (p (<) 0.001), 5H (p (<) 0.001) and 24H (p = 0.005; p = 0.006) in PPB and PL, respectively. Classical monocyte proportions were lower in PPB (p = 0.008) and PL (p = 0.003) than CON at IP, and significantly greater than CON at 1H (PPB: p = 0.002; PL: p = 0.006). Nonclassical monocyte proportions were significantly greater in PPB (p = 0.020) and PL (p = 0.028) than CON at IP. Intermediate monocyte proportions were significantly greater in PPB (p = 0.034) and PL (p = 0.001) than CON at IP, and significantly lower than CON at 1H (PPB: p = 0.003; PL: p = 0.008). Intermediate monocyte proportions were also significantly greater in PPB than CON at 24H (p = 0.016) and 48H (p = 0.007). At PRE, CD11b expression was significantly lower in the PPB group than CON and PL for intermediate (p = 0.017; p = 0.045) and nonclassical (p (<) 0.001, p = 0.019) monocytes, respectively. When groups were combined, CD11b expression was significantly elevated from PRE at IP (p (<) 0.001) and 1H (p = 0.015) on granulocytes. CD11b expression on classical monocytes was significantly elevated compared to PRE at 1H (p (<) 0.001), 5H (p = 0.033) and 24H (p = 0.004) when groups were combined. CD11b expression on intermediate monocytes was significantly elevated compared to PRE at 1H (p (<) 0.001) when groups were combined. Intermediate and nonclassical monocyte proportions also showed significant positive correlations with markers of muscle damage (r = 0.361 to 0.775, p(<)0.05). Results indicated that resistance exercise in novice lifters may elicit a selective mobilization of intermediate monocytes at 24h and 48H, and that muscle damage may be related to increases in intermediate and nonclassical monocytes. In addition, polyphenol supplementation appeared to suppress CD11b expression on monocytes to resistance exercise.
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Date Issued
2016
Identifier
CFE0006119, ucf:51177
Format
Document (PDF)
PURL
http://purl.flvc.org/ucf/fd/CFE0006119
A high-content multiplexed screening platform for the evaluation and manipulation of force and fatigue of adult derived skeletal muscle myotubes in defined serum-free medium
Title
A high-content multiplexed screening platform for the evaluation and manipulation of force and fatigue of adult derived skeletal muscle myotubes in defined serum-free medium.
Creator
McAleer, Christopher, Hickman, James, Ebert, Steven, Perez Figueroa, J. Manuel, Lambert, Stephen, University of Central Florida
Abstract / Description
The overall focus of this project has two parts: First, was to develop a protocol utilizing serum-free media formulations and defined plating and culture techniques to create functional in vitro myotubes derived from adult skeletal muscle satellite cells. The second was to manipulate the inherent muscle parameters such as force output and fatigue of these myotubes by employing exercise regimes or by small molecule application. The importance of serum-free medium use for in vitro cultures is...
Show moreThe overall focus of this project has two parts: First, was to develop a protocol utilizing serum-free media formulations and defined plating and culture techniques to create functional in vitro myotubes derived from adult skeletal muscle satellite cells. The second was to manipulate the inherent muscle parameters such as force output and fatigue of these myotubes by employing exercise regimes or by small molecule application. The importance of serum-free medium use for in vitro cultures is becoming increasingly important in creating functional systems that can be validated for drug testing by the Food and Drug Administration (FDA). Also, the study of age related diseases as well as the potential for (")personalized medicine(") relies on the proliferation and maturation of satellite cells from adult derived tissue. For that purpose, a serum-free medium and culture system was designed to create mature striated myotubes in culture on a defined non-biological substrate N-1[3-trimethoxysilyl propyl] diethylenetriamine (DETA). These myotubes were evaluated by morphology, muscle specific protein expression, and by muscle functionality. After the thorough characterization of the resultant myotubes the functional output of the muscle was altered utilizing chemical means (creatine supplementation and PGC-1? agonists), chronic long term stimulation, and the use of PGC-1? deficient tissue. In this thesis presentation the utility of the newly developed medium formulation to create myotubes from a variety of adult derived muscle sources will be shown. A protocol in which to exercise skeletal muscle in vitro to alter endurance was developed and employed to manipulate skeletal muscle. Finally, small molecules were tested to validate this system for drug study use. This engineered system has the potential for high-throughput screening of drugs for efficacy and drug toxicity studies as well as general biological studies on muscle fatigue.
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Date Issued
2015
Identifier
CFE0005660, ucf:50162
Format
Document (PDF)
PURL
http://purl.flvc.org/ucf/fd/CFE0005660
THE EFFECTS OF GROWTH HORMONE AND THYROXINE TREATMENT ON THE INSULIN SIGNALING OF FEMALE AMES DWARF MOUSE SKELETAL MUSCLE TISSUE
Title
THE EFFECTS OF GROWTH HORMONE AND THYROXINE TREATMENT ON THE INSULIN SIGNALING OF FEMALE AMES DWARF MOUSE SKELETAL MUSCLE TISSUE.
Creator
Do, Andrew, Masternak, Michal, University of Central Florida
Abstract / Description
Ames dwarf (df/df) mice are deficient in anterior pituitary hormones: growth hormone (GH), thyroid stimulating hormone (TSH), and prolactin (PRL) due to a spontaneous, homozygous mutation of prop1df gene. These dwarf mice exhibit characteristics such as delayed growth and development coupled with delayed aging, increased lifespan, overall increased insulin sensitivity, as well as resistance to certain diseases and cancers. The mutant mice possess low blood glucose, low serum insulin, and...
Show moreAmes dwarf (df/df) mice are deficient in anterior pituitary hormones: growth hormone (GH), thyroid stimulating hormone (TSH), and prolactin (PRL) due to a spontaneous, homozygous mutation of prop1df gene. These dwarf mice exhibit characteristics such as delayed growth and development coupled with delayed aging, increased lifespan, overall increased insulin sensitivity, as well as resistance to certain diseases and cancers. The mutant mice possess low blood glucose, low serum insulin, and lower body temperature. Their enhanced longevity (about 40-60% longer lifespan than normal mice) is associated with their GH deficiency and disruption in the somatotropic axis (GH/IGF-1 hormonal pathway) as well as increased insulin sensitivity, which is supported by other mutant mouse models for longevity like Snell dwarfs and growth hormone receptor knock-out (GHRKO) mice. When young male Ames dwarf mice were treated with GH replacement therapy, they showed increased body growth to nearly match the normal mouse phenotype. In conjunction to an increase in physical growth, however, GH treatment also decreases the longevity and insulin sensitivity that are characteristic of these mice to levels seen in normal mice. Because of the lack of TSH, they also have undetectable levels of Thyroxine (T4). While T4 treatment didn't increase bodyweight of dwarfs to the same extent as GH treatment, the T4 treated mice retained their enhanced lifespan. Although df/df mice have enhanced whole-body insulin sensitivity, the male skeletal muscle was previously shown to be less responsive to insulin than their liver. In our study we analyzed the insulin signaling pathway in skeletal muscle from female mice after treatment with GH or GH combined with T4. Gene expression and protein expression were investigated in the skeletal muscle of female Ames dwarf mice that were treated with GH or GH and T4 therapy. Real Time Polymerase Chain Reaction (RT-PCR) was used to analyze the expression of mRNA involved with insulin and GH signaling, while western blots were used to analyze protein expression. This project found that female Ames skeletal muscle didn't respond to GH treatment to the same extent as males, and that GH and T4 treatment tends to neutralize the effects seen in GH-only treatment.
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Date Issued
2013
Identifier
CFH0004483, ucf:45074
Format
Document (PDF)
PURL
http://purl.flvc.org/ucf/fd/CFH0004483
Biomechanical Factors Influencing Treatment of Developmental Dysplasia of the Hip (DDH) with the Pavlik Harness
Title
Biomechanical Factors Influencing Treatment of Developmental Dysplasia of the Hip (DDH) with the Pavlik Harness.
Creator
Ardila, Orlando, Kassab, Alain, Moslehy, Faissal, Divo, Eduardo, University of Central Florida
Abstract / Description
Biomechanical factors influencing the reduction of dislocated hips with the Pavlik harness in patients of Developmental Dysplasia of the Hip (DDH) were studied using a simplified three-dimensional computer model simulating hip reduction dynamics in (1) subluxated, and (2) fully dislocated hip joints. The CT-scans of a 6 month-old female infant were used to measure the geometrical features of the hip joint including acetabular and femoral head diameter, acetabular depth, and geometry of the...
Show moreBiomechanical factors influencing the reduction of dislocated hips with the Pavlik harness in patients of Developmental Dysplasia of the Hip (DDH) were studied using a simplified three-dimensional computer model simulating hip reduction dynamics in (1) subluxated, and (2) fully dislocated hip joints. The CT-scans of a 6 month-old female infant were used to measure the geometrical features of the hip joint including acetabular and femoral head diameter, acetabular depth, and geometry of the acetabular labrum, using the medical segmentation software Mimics. The lower extremity was modeled by three segments: thigh, leg, and foot. The mass and the location of the center of gravity of each segment were calculated using anthropometry, based on the total body mass of a 6-month old female infant at the 50th length-for-age percentile. A calibrated nonlinear stress-strain model was used to simulate muscle responses. The simplified 3D model consists of the pubis, ischium, acetabulum with labrum, and femoral head, neck, and shaft. It is capable of simulating dislocated as well as reduced hips in abduction and flexion.Five hip adductor muscles were identified as key mediators of DDH prognosis, and the non-dimensional force contribution of each in the direction necessary to achieve concentric hip reductions was determined. Results point to the adductor muscles as mediators of subluxated hip reductions, as their mechanical action is a function of the degree of hip dislocation. For subluxated hips in abduction and flexion, the Pectineus, Adductor Brevis, Adductor Longus, and proximal Adductor Magnus muscles contribute positively to reduction, while the rest of the Adductor Magnus contributes negatively. In full dislocations all muscles contribute detrimentally to reduction, elucidating the need for traction to reduce Graf IV type dislocations. Reduction of dysplastic hips was found to occur in two distinct phases: (a) release phase and (b) reduction phase.To expand the range of DDH-related problems that can be studied, an improved three-dimensional anatomical computer model was generated by combining CT-scan and muscle positional data belonging to four human subjects. This model consists of the hip bone and femora of a 10-week old female infant. It was segmented to encompass the distinct cartilaginous regions of infant anatomy, as well as the different regions of cortical and cancellous bone; these properties were retrieved from the literature. This engineering computer model of an infant anatomy is being employed for (1) the development of a complete finite element and dynamics computer model for simulations of hip dysplasia reductions using novel treatment approaches, (2) the determination of a path of least resistance in reductions of hip dysplasia based on a minimum potential energy approach, (3) the study of the mechanics of hyperflexion of the hip as alternative treatment for late-presenting cases of hip dysplasia, and (4) a comprehensive investigation of the effects of femoral anteversion angle (AV) variations in reductions of hip dysplasia. This thesis thus reports on an interdisciplinary effort between orthopedic surgeons and mechanical engineers to apply engineering fundamentals to solve medical problems. The results of this research are clinically relevant in pediatric orthopaedics.
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Date Issued
2013
Identifier
CFE0004646, ucf:49907
Format
Document (PDF)
PURL
http://purl.flvc.org/ucf/fd/CFE0004646
Role of Lipid Peroxide Derived Dicarboxylic Acids in Atherosclerotic Calcification
Title
Role of Lipid Peroxide Derived Dicarboxylic Acids in Atherosclerotic Calcification.
Creator
Riad, Aladdin, Parthasarathy, Sampath, Altomare, Deborah, Masternak, Michal, Naser, Saleh, University of Central Florida
Abstract / Description
Cardiovascular diseases, including atherosclerosis, are the leading cause of death in the United States. Atherosclerotic lesions are formed by deposition of lipids in the intima of arteries. Upon exposure to oxidative stresses, low-density lipoprotein (LDL) is converted to highly atherogenic oxidized LDL (ox-LDL) particles, contributing to disease development and progression. Advanced disease stages may result in calcification of lesions. This calcification process is important, as it has...
Show moreCardiovascular diseases, including atherosclerosis, are the leading cause of death in the United States. Atherosclerotic lesions are formed by deposition of lipids in the intima of arteries. Upon exposure to oxidative stresses, low-density lipoprotein (LDL) is converted to highly atherogenic oxidized LDL (ox-LDL) particles, contributing to disease development and progression. Advanced disease stages may result in calcification of lesions. This calcification process is important, as it has been shown to be associated with stable plaques that are less prone to rupture. Calcification is present in lipid rich domains of lesions, however neither the composition of the mineralized calcium deposits nor its relationship to lipid peroxidation or the lipid rich atherosclerotic core has previously been identified. This study provides evidence that the lipid peroxide derived dicarboxylic acid (DCA), azelaic acid (AzA) induces calcification in smooth muscle cells, thereby providing the link between calcification and overall plaque burden, and association of calcification with the lipophilic region of the lesion. The potential of lipid peroxide-derived lipophilic DCAs to promote calcification upon exposure to vascular smooth muscle cells was tested. 13-hydroperoxylinoleic acid (HPODE) treatment resulted in the cellular conversion to 9-oxononanoic acid (ONA) and AzA as determined by mass spectrometry analysis. Delivery of AzA via lysophosphatidylcholine (Lyso-PtdCho) micelles induced calcification of human aortic smooth muscle cells (HASMC). AzA was identified in calcified human and mouse atherosclerotic plaques. Calcification of HASMC due to AzA treatment resulted in a less inflammatory and oxidative environment as indicated by genetic expression. These results demonstrate that DCAs may contribute to atherosclerotic calcification thus accounting for the latter's relationship to plaque burden and association with lipids. This study also challenges the dogma that arterial calcification represents the deposition of calcium phosphate and has implications with the development of new therapeutic strategies in treating late stage atherosclerosis.
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Date Issued
2018
Identifier
CFE0007413, ucf:52730
Format
Document (PDF)
PURL
http://purl.flvc.org/ucf/fd/CFE0007413
Effects of an Acute High-Volume Isokinetic Intervention on Circulating Levels of TNF-? and STNFR: Influence of Age
Title
Effects of an Acute High-Volume Isokinetic Intervention on Circulating Levels of TNF-? and STNFR: Influence of Age.
Creator
Arroyo Delgado, Eliott, Wells, Adam, Hoffman, Jay, Stout, Jeffrey, Fukuda, David, University of Central Florida
Abstract / Description
The immune system has been implicated in recovery and muscle regeneration following exercise. In response to muscle damage, the immune system responds with an increase in circulating pro-inflammatory cytokines with the goal of recruiting leukocytes to the damaged area. Tumor Necrosis Factor-alpha (TNF-?), in particular, has been shown to be implicated in both muscle regeneration and muscle wasting. However, it remains unclear whether TNF-? is responsible for the age-related losses in muscle...
Show moreThe immune system has been implicated in recovery and muscle regeneration following exercise. In response to muscle damage, the immune system responds with an increase in circulating pro-inflammatory cytokines with the goal of recruiting leukocytes to the damaged area. Tumor Necrosis Factor-alpha (TNF-?), in particular, has been shown to be implicated in both muscle regeneration and muscle wasting. However, it remains unclear whether TNF-? is responsible for the age-related losses in muscle size and function. Also, due to the high clearance rate of TNF-? from circulation, analyzing the circulating levels of soluble TNF-? receptors 1 and 2 (STNFR1 and STNFR2) may provide a better indication of inflammatory events. Therefore, the purpose of this study was to compare changes in circulating levels of TNF-?, STNFR1, and STNFR2 following an acute muscle damaging intervention in young age (YA) and middle-aged (MA) males. Recreationally active young (YA; N=9, 21.8 (&)#177; 2.2 y, 179.5 (&)#177; 4.9 cm, 91.2 (&)#177; 12.2 kg, 21.8 (&)#177; 4.3% BF) and middle-aged (MA; N=10, 47.0 (&)#177; 4.4 y, 176.8 (&)#177; 7.6 cm; 96.0 (&)#177; 21.5 kg, 25.4 (&)#177; 5.3% BF) males completed an acute muscle damaging protocol (MDP). Blood samples were obtained at baseline (BL), immediately (IP), 30 minutes (30P), 60 minutes (60P), 120 minutes (120P), 24 hours (24H), and 48 hours (48H) post-MDP. Lower body performance was analyzed via isokinetic dynamometer at BL, IP, 120P, 24H, and 48H. No significant group x time interactions or main group effects were observed for TNF-?, STNFR1, STNFR2 or any marker of muscle damage. When collapsed across groups, plasma lactate was significantly elevated at IP (p (<) 0.001) and 30P (p = 0.003); serum myoglobin was increased at 30P (p = 0.002), 60P (p = 0.001), and 120P (p = 0.007); creatine kinase was elevated at 24H (p = 0.001) and 48H (p = 0.005). Plasma concentrations of TNF-? were unchanged following MDP. With both groups combined, serum STNFR1 was decreased at 30P (p = 0.001) and increased at 48H (p = 0.028). Serum STNFR2 was decreased at 30P (p = 0.008), 60P (p = 0.003), and 120P (p = 0.002). The results of this study indicate that the TNF-? and STNFRs response to exercise is similar between young and middle-aged males. Measuring STNFRs may be a more appropriate method of assessing the acute inflammatory response to muscle damage. In addition, an acute bout of exercise may attenuate ectodomain shedding of TNFR1 and TNFR2.
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Date Issued
2017
Identifier
CFE0006561, ucf:51350
Format
Document (PDF)
PURL
http://purl.flvc.org/ucf/fd/CFE0006561