bluuebunny/crossref_metadata_2025_split huggingface dataset:
Determinants of muscle protein synthesis in severe pediatric burns (703.5)
Authors: Diaz Fuentes Eva , Potter Craig , Cotter Matthew , Lee Jinhyung , Herndon David , Borsheim Elisabet 
Published: June 2021

Introduction: Following a major burn, a large increase in skeletal muscle protein breakdown is seen. The simultaneous increase in muscle protein synthesis cannot completely compensate for the breakdown, resulting in net protein loss. The aim of this study was to identify the determinants of skeletal muscle protein fractional synthetic rate (FSR) in severely burned children. Methods: 87 patients with 蠅40% Total Body Surface Area (TBSA) burns were included. Patients participated in stable isotope infusion studies during their acute hospitalization and at 6, 12 and 24 months post injury in order to determine skeletal muscle FSR. Generalized estimating equations with log link normal distribution were applied to account for clustering of patients and control for patient characteristics. Results: Patients (8±6 yr) had large (59±14 % TBSA), deep (47±21% 3rd degree) burns. Time was a significant determinant, with a decrease in FSR [%/h, median (Q1‐Q3)] at 12 months vs. admission [0.08 (0.05‐0.18)vs. 0.12 (0.07‐.0.24)] (P<0.05). Further, FSR was 48% higher in childrenwith co‐existent inhalation injury vs. those with burn injury alone. Inaddition, FSR was 36% lower in male vs female kids, while children >3 years had 30% lower FSR values than younger children. Finally, FSR was significantly lower in patients with burns 蠅60% TBSA. Conclusion: The current data demonstrate that burn size, gender; the presence of inhalation injury and time all affect the rate of skeletal muscle FSR following burn injury. The impact of these findings on net protein balance remains unknown and warrants further investigation.Grant Funding Source: Supported by NIH P50‐GM60338, RO1‐GM056687, T32‐GM008256, and Shriners grants 84090, 84080, 71006/08
Evaluation of long‐haul shipping stress for beef calves transported from Hawaii to the contiguous United States (703.7)
Authors: Sy Tracy , Richards Tim , Lee C. , Onaga Jonathan , Coetzee Johann , Stock Matt , Stokes Ashley 
Published: June 2021

Objectives of this study were to examine physiological parameters of weaned calves being shipped to determine response to long‐haul shipping; also, to determine the animals’ ability to adapt to the stress of shipment. Two shipments of weaned, Angus and Charolaise, female calves (n=48) were transported to Washington or California. Each shipment, the calves were divided and placed into two separate, bi‐level, four‐compartment, custom cowtainers. Vaginal temperatures (T°) were taken every minute. Blood was collected prior to shipment (P), upon arrival (A), and 6 days post‐arrival (PA). Blood work parameters (including substance‐P (SP), hematocrit % (H), bands (B), and white blood cell (WBC) numbers and differentials) were also used to determine physiological status of the animals. Overall T° values did not change significantly. T° only increased above normal range during insertion of temperature sensor, loading, unloading, trucking, and at Kawaihae, Hawaii. SP values showed a significant increase from P to A (p<0.001) and decrease back to normal from A to PA (p<0.001). SP values had no significant change from P to PA (p=0.45). WBC and B showed no significant differences for any time points. HCT significantly decreased from P to A and from P to PA (p<0.001). HCT values stayed within normal range for all stages. The study showed some physiological changes with shipping, however, animals quickly returned to a homeostatic physiological state.Grant Funding Source: Supported by National Cattlemen's Beef Association
FNDC5 expression in skeletal muscle in chronic heart failure: relevance of inflammatory cytokines (704.1)
Authors: Adams Volker , Gleitsmann Konstanze , Mangner Norman , Bowen T Scott , Schuler Gerhard , Linke Axel 
Published: June 2021

Chronic heart failure (CHF) is associated with muscle atrophy. Irisin, a myokine proteolytically processed by the FNDC5 protein and suggested to be PGC‐1α activated, modulates the browning of adipocytes and is related to muscle mass. Therefore, we investigated whether skeletal muscle FNDC5 expression in CHF was reduced and if this was mediated by inflammatory cytokines and/or angiotensin II (Ang‐II).Methods: Skeletal muscle FNDC5 mRNA/protein and PGC‐1α mRNA expression were analyzed in: Rats with CHF; Mice injected with TNF‐α (24h); Mice infused with Ang‐II (4 wk); C2C12 myotubes exposed to recombinant cytokines or Ang‐II. Results: CHF reduced (p<0.05) FNDC5 protein (1.3±0.2 vs. 0.5±0.1 arb. units) and PGC‐1α mRNA expression (8.2±1.5 vs. 4.7±0.7 arb. units) compared to control. TNF‐α and Ang‐II reduced FNDC5 protein by 28% and 45%, respectively. Incubation of myotubes for 24h with a TNF‐α, IL‐1ß, and IFN‐ γ cocktail reduced (p<0.05) FNDC5 protein expression by 71%, whereas Ang‐II had no effect. PGC‐1α was linearly correlated to FNDC5 in all conditions.Conclusion: Skeletal muscle FNDC5 expression is reduced in CHF, which seems mediated by inflammatory cytokines, Ang‐II, and PGC‐1α.This suggests a reduced FNDC5 expression may act as a protective mechanism in catabolic states, by preserving energy homeostasis via slowing the browning of adipocytes.
Systemic and lower limb hemodynamics following dynamic exercise in type 2 diabetics: effects of exercise intensity and duration (705.12)
Authors: Pellinger Thomas , Neighbors Catherine , Snitzer Jack 
Published: June 2021

For individuals with type 2 diabetes mellitus (T2DM), regular exercise is critical for protecting vascular function and reducing cardiovascular disease risk, but the hemodynamic responses to differing doses of acute exercise in type 2 diabetics (T2D) are unclear. Our aim was to compare postexercise (PE) hemodynamics in T2D in response to four different doses of acute dynamic exercise. Two subjects with well‐controlled T2DM (42‐48 yrs; Hemoglobin A1c: 6.6 ± 0.7%) participated in four study days, during which they exercised on an upright cycle ergometer at four different combinations of exercise duration and intensity: 30 min at 40% VO2 peak (30@40), 30 min at 60% VO2 peak (30@60), 60 min at 40% VO2 peak (60@40), and 60 min at 60% VO2 peak (60@60). Heart rate, arterial pressure, and femoral blood flow (Doppler ultrasound) were measured pre‐exercise and every 15 min through 120 min PE. Femoral vascular conductance (FVC) was calculated as flow/pressure. Compared to pre‐exercise baseline, FVC was higher and mean arterial pressure (MAP) was lower throughout 120 min of recovery in all conditions, except for the 30@40 trial. Expressed as percentage change from pre‐exercise baseline, at 30 min PE, FVC was elevated 7.8 ± 1.3% on the 30@40 day, 32.3 ± 1.9% on the 30@60 day, 40.7 ± 4.6% on the 60@40 day, and 43.9 ± 9.0% on the 60@60 day. Compared to pre‐exercise baseline, at 30 min PE, MAP was reduced 0.53 ± 0.6% on the 30@40 day, 2.1 ± 2.9% on the 30@60 day, 4.2 ± 0.2% on the 60@40 day, and 6.1 ± 0.6% on the 60@60 day. These preliminary results suggest a somewhat dose‐dependent elevation of PE skeletal muscle blood flow and reduction in PE MAP in T2D.Grant Funding Source: Supported by the Salisbury University Faculty Mini‐Grant
The Ironman Triathlon shifts innate/adaptive immune cell populations and increases systemic inflammation (705.3)
Authors: Munoz Colleen , Apicella Jenna , Radom‐Aizik Shlomit , Maresh Carl , Haddad Faddia , Cooper Dan , Nugas Cherryl , Zaldivar Frank , Casa Douglas , Lee Elaine 
Published: June 2021

The Ironman Triathlon shifts innate/adaptive immune cell populations and increases systemic inflammation Colleen X. Munoz1, Jenna M. Apicella1, Shlomit Radom‐Aizik2, Carl M. Maresh1, Fadia Haddad2, Dan M Cooper2, Cherryl Nugas2, Frank P Zaldivar2, Douglas J. Casa1, Elaine C. Lee1 1University of Connecticut, Storrs, CT2University of California Irvine, Irvine, CA Exercise and environmental stressors threaten cellular function and integrity. We recently showed that whole body acute stress determines the extent of measurable cellular stress. In this study, we tested the hypothesis that the profile of circulating immune cells, level of systemic inflammation, and chaperone response would reflect the whole body stress of an Ironman. To test this hypothesis, we recruited 40 race participants (29 males, 11 females) and 17 control subjects (9 males, 8 females). Blood was drawn between 2‐3 days before the triathlon (baseline), and during recovery at 1‐, 24‐, and 48‐h after completion. CBC (with differential), multiplex cytometric bead array, and ELISA were used to determine cell counts, inflammatory cytokines, and chaperone HSP70, respectively. Statistical significance was defined by repeated measure ANOVA with Bonferroni‐corrected post hoc tests (p<0.05). Total white blood cell counts increased post‐exercise and returned to normal by 48h post‐race. Neutrophil and monocyte subsets increased post‐exercise and remained elevated even 2 days post‐race, while lymphocyte, eosinophil, and basophil subsets transiently decreased post‐exercise before increasing above normal 24h and 48h later. Inflammatory cytokines IL‐10, IL‐6, and IL‐8 increased >10 fold post‐race and returned to normal by 24h post‐race. HSP70 similarly increased ~2‐fold post‐ race and returned to normal levels by 24h later. The stress of the Ironman event likely shifted the balance of innate/adaptive immune cells, and induced a systemic inflammatory response and chaperone response.Grant Funding Source: Timex, Inc.
Strain‐dependent variation in transcriptional activation of metabolic and angiogenic genes after acute exercise in mouse skeletal muscle (705.8)
Authors: Kim Seung , Avila Joshua , Massett Michael 
Published: June 2021

Repeated bouts of exercise can lead to metabolic and vascular adaptation in skeletal muscle, and the magnitude of the adaptation is determined, in part, by genetic background. The aim of this study was to test the hypothesis that the transcriptional response to an acute bout of exercise would be different between high and low responders to training. Gene expression for seven metabolic and nine angiogenic genes was assessed in plantaris muscles from FVB/NJ (FVB, high responder) and C57BL/6J (B6, low responder), which were harvested before and 0, 3, 6, 12, and 24 h (n=4/each) after an acute bout of exercise on a treadmill (60 min, 18m/min, 10° incline). Significant strain effects were found for mRNA expression of several metabolic and angiogenic genes. The peak of PGC1α mRNA was found at 3 h (p < 0.01) in both strains, showing greater increase (36 %) in FVB than B6. Nrf2 mRNA was increased at 0 h in FVB and 3 h in B6. Nrf1 mRNA was decreased at 3‐24 h in FVB. Interestingly MyoG mRNA changed in opposite directions (P < 0.05) for B6 and FVB; B6 decreased at 6‐24 h and FVB increased at 3‐6 h. VEGFa and eNOS mRNAs were increased at 0 h only in FVB. Unexpectedly both B6 and FVB showed increased TSP1 and reduced HIF1α mRNA at 0 h. These data indicate that genetic background influences the transcriptional activation of metabolic and angiogenic genes in response to an acute bout of exercise in mouse skeletal muscle.Grant Funding Source: Supported by NIH grant HL085918 to MPM
Combined exercise training improves cardiovascular and inflammatory parameters in an experimental model of metabolic syndrome and menopause (706.12)
Authors: Conti Filipe , Brito Janaina , Dias Danielle , Bernardes Nathalia , Sanches Iris , Malfitano Christiane , Irigoyen Maria Claudia , De Angelis Kátia 
Published: June 2021

The aim of this study was to verify the effects of combined exercise training (aerobic+resistance) in an experimental model of metabolic syndrome and menopause on cardiovascular autonomic modulation and inflammation. Female SHR rats were divided into (n=8/group): hypertensive (H), hypertensive ovariectomized (HO) and hypertensive ovariectomized submitted to fructose overload sedentary (100g/L in drinking water) (FHO) or trained (FHOT). Combined exercise training was performed in ladder+treadmill on alternate days (5x/week, 8 weeks, 40‐60% maximal exercise test). Arterial pressure (AP) signals were directly recorded. Cardiovascular autonomic modulation was evaluated by spectral analysis. Cardiac levels of TNFα and IL‐10 were measured by Elisa. AP was higher in FHO group (174±4 vs. H: 146±4 HO: 164±5 mmHg) and combined exercise training attenuated this dysfunction (FHOT: 158±4 mmHg). FHOT group showed resting bradycardia. The vascular sympathetic modulation (LF‐IP) was higher in FHO group (10.62±2.33 mmHg2) and exercise training normalized this change (4.51±0.32 vs. H: 5.06±0.91; HO: 5.07±0.52 mmHg2). The TNFα was higher in FHO group than H and HO groups and exercise training reduced this parameter. Negative correlation was observed between adiposity tissue and IL‐10 among sedentary groups (r=‐0.6, p<0.05). In conclusion, fructose overload induced impairment in cardiovascular autonomic control and in inflammatory parameters in hypertensive rats undergoing ovarian hormones deprivation. The combined exercise training reverted and/or attenuated these impairments.Grant Funding Source: FAPESP 2011/15828‐9
Effects of impact‐loaded sport training on bone bending stiffness and BMD in young females (706.16)
Authors: Liang Michael , Robles Patricia , Rocha Jose , Spalding Thomas 
Published: June 2021

BLACKGROUND: Participation in high‐impact loading or odd‐impact loading sports is associated with higher bone mineral density (BMD) and bone mass. OBJECTIVE: The objective of this study is to compare the impact of sport training in long‐distance running, soccer and volleyball practice on BMD and bone bending strength in female athletes, 18‐24 years old.METHODS. 57 trained female athletes participated in this study. They were 22 soccer players (SOC), 22 long‐distance runners (RUN), and 13 volleyball players (VOL). Their ages were 19.1, 20.5 and 21.5 yr for the SOC, RUN and VOL, respectively. Sport training history was: 13, 11 and 10 yr for the SOC, RUN and VOL, respectively. Mean height, weight and BMI were 163 cm (±4.7), 59.8 kg (±4.1) and BMI 22.6 kg/m2 (±1.9), respectively. We also recruited 23 non‐athlete females, age 22.6 ± 0.5 yr, as control subjects. Bone bending stiffness was measured using a Mechanical Response Tissue Analyzer (MRTA, NASA‐ARC, CA), an in vivo technique expressed as EI in Nm2. EI was measured at the ulna and tibia. BMD was measured using a Duel‐Energy X‐ray Absorptiometry (PIXI‐DXA, in g/cm2) at two skeletal sites: heel and wrist.RESULTS. There are no differences in height, weight and BMI between the groups, except that VOL were significantly heavier and taller than the other groups. Tibia EI (TEI) of the RUN (122.7±89 Nm2) were significantly lower (p<0.05) than VOL (228±89 Nm2), but not SOC (152±89 Nm2) and CON (85±89 Nm2). RUN has the lower ulnar EI (UEI=30.7±14 Nm2) relative to SOC (44±14 Nm2) and VOL (44±14 Nm2). VOL has significantly higher TEI (228.3±89 Nm2, p<0.05) compared with SOC, RUN and CON. Heel and wrist BMD of the SOC and VOL are 7% to 9.5% higher (p<0.05) than the RUN and CON.CONCLUSION. Volleyball training exhibited greatest osteogenic adaptation in tibial EI compared with RUN and CON, but not in ulnar EI or heel and wrist BMD. Distance running did not induce high osteogenic adaptation in the tibial EI or heel BMD. The mechanism for these changes in bone EI and BMD is unknown.
Sequential effects of aerobic training upon muscular and renal arteries in hypertensive rats (706.8)
Authors: Alves Tatiana , Batista Junior Alvaro , Al Chaar Laiali , Barboza Tatiane , Oliveira Thais Cristina , Michelini Lisete , Lacchini Silvia 
Published: June 2021

This study evaluated if aerobic training determine an arteriolar remodeling in locomotor and non‐locomotor skeletal muscle, heart and kidney of hypertensive (SHR) and normotensive (WKY) rats.Were used SHR and WKY male rats 10 weeks‐age submitted or not to aerobic training (AT, 1hr, 5 times/week, in treadmill). Rats were trained for 1, 2, 4, 8 and 12 weeks (55% of maximal capacity) or kept sedentary for 0 and 12 weeks (n=8/group). At the end of each time, mean arterial pressure (MAP) and heart rate (HR) were measured. Heart and locomotor (soleus, gastrocnemius) and non‐locomotor (temporalis) skeletal muscles (SM), heart and kidneys were harvested for arteriolar wall/lumen ratio measurements. Results were compared by ANOVA, using Bonferroni as post‐test. p蠄0.05 was considered as significant.Both SHR and WKY improved physical performance after 6 and 12 weeks of AT (S0:1.02±0.3 vs 1.62±0.4, T6:1.32±0.2 vs 2.09±0.3, T12:1.92±0.4 vs 2.40±0.4 km/h, WKY vs SHR). AT induced a rest bradycardia in WKY (326±4 to 294±3bpm), and in SHR (385±7 to 357±2bpm). Only SHR reduced MAP after AT (174±2 to 164±1mmHg). SHR showed increased arteriolar wall/lumen ratio compared to WKY (soleus: 0.19±0.02 vs 0.10±0.01µm; gastrocnemius red fibers (GRF): 0.20±0.02 vs 0.10±0.01µm; gastrocnemius white fibers (GWF): 0.21±0.01 vs 0.11±0.01µm; and temporalis: 0.19±0.01 vs 0.13±0.01µm; heart: 0.22±0.02 vs 0.12±0.02µm; kidney: 0.26±0.03 vs 0.15±0.01µm). On the other hands, AT decreased arteriolar wall/lumen ratio in SHR in locomotor SM (soleus: ‐47%; GRF: ‐50%; GWF: ‐52%), non‐locomotor SM (temporalis: ‐32%), and in heart ‐45%), with no changes in Kidney arterioles.The data indicates that AT induced beneficial vascular remodeling after hemodynamic adjusts, improving arteriolar wall/lumen ratio of SHR, and these modifications seems to be depending also of metabolic and systemic (hemodynamic and sympathetic) mechanisms.Grant Funding Source: Supported by FAPESP
Drinking patterns in relation to hydration status in children (707.10)
Authors: Kavouras Stavros , Bougatsas Dimitrios , Arnaoutis Giannis , Tsipouridi Spiridoula , Panagiotakos Demosthenes 
Published: June 2021

Children are known to consume various fluids in order to cover their water needs. However the contribution of the different fluid categories to hydration is still unknown in children. PURPOSE: To examine whether various drinking patterns are associated with different hydration levels. METHODS: Two hundred and ten Greek healthy children, 105 girls (height: 1.49±0.13 m, weight: 44.1±12.9 kg, fat: 27.7±7.1%) and 105 boys (height: 1.49±0.14 m, weight: 42.6±12.3 kg, fat: 22.8 ± 7.7%) were asked to collect their urine for 24 hours while conducting normal daily activities during autumn and winter months. They were also instructed to record the fluids they consumed in a diary specially designed for children, for two consecutive days. Urine samples were analyzed for color (Ucol) via an eight‐point scale, urine specific gravity (USG) via a hand‐held refractometer, and urine osmolality (Uosm) via freezing point depression osmometry. Principal components analysis was applied to extract dietary patterns from 9 drinks or drinking groups. Multivariate regression analysis evaluated the associations between the extracted dietary patterns and hydration levels deriving from 24h urine osmolality. RESULTS: Six principal components were extracted from the analysis. Component 1 was mainly characterized by consumption of milk, but not water, component 2 by packaged juice and sugar sweetened drinks (SSD) but not Natural Juice, component 3 by natural juice and rest drinks, component 4 by packaged juice, component 5 by water and milk and component 6 by natural juice and SSDs. Component 5 was inversely correlated with hypohydration (P=0.006), whereas none of the other components was associated with the outcomes. CONCLUSION: A drinking pattern that includes water and milk seems to promote better hydration.Grant Funding Source: Danone Research
Respiratory pump contributes to increased physiological reserve for compensation during reductions in central blood volume (707.4)
Authors: Poh Paula , Carter Robert , Hinojosa‐Laborde Carmen , Mulligan Jane , Grudic Gregory , Convertino Victor 
Published: June 2021

The impedance threshold device (ITD) represents a therapy for increasing systemic circulation through creation of negative intrathoracic pressure. PURPOSE: To evaluate the respiratory pump effect on the diminution of compensatory responses during progressive reductions in central blood volume. METHODS: The Compensatory Reserve Index (CRI) algorithm measured compensation capacity to reduced central blood volume. Continuous analog recordings of arterial waveforms were extracted from data files of 7 volunteers. Subjects had previously participated in experiments designed to induce hemodynamic decompensation by application of graded lower body negative pressure (LBNP). The LBNP protocol was completed while spontaneously breathing through a standard medical facemask without (sham ITD) and with (active ITD) a resistance (~‐7cmH2O). RESULTS: At the onset of pre‐syncope in the sham ITD, CRI (0.08±0.02) was smaller (P=0.05) than CRI at the same time point in the active ITD (0.09±0.01). CRI at pre‐syncope in the active ITD (0.08±0.01) was similar (P=0.19) to CRI at pre‐syncope in the sham ITD. Kaplan‐Meier and log rank tests indicated that CRI survival curves shifted to the right (P=0.04) by the active ITD. CONCLUSIONS: Optimizing the respiratory pump contributed a small but significant effect of increasing tolerance to progressive reductions in central blood volume by extending the compensatory reserve.Grant Funding Source: U.S. Army MRMC Combat Casualty Care Research Program
Role of carotid bodies in glucose counterregulation in type 1 diabetes (709.2)
Authors: Dube Simmi , Shonkwiler Cheryl , McConahey Brent , Joyner Michael , Basu Ananda , Basu Rita 
Published: June 2021

Carotid bodies (CB) are desensitized by hyperoxia/hyperglycemia and sensitized by hypoxia/hypoglycemia. We have reported in healthy humans that CB chemoreceptors secrete counterregulatory hormones in response to normoxia and hypoglycemia. While the role of central nervous system in glucose counterregulation is known, it is unknown whether alteration in CB response to glucose contributes to the pathogenesis of hypoglycema in T1D. We hypothesized that glucose counterregulation is impaired in T1D due to reduced sensitization of CB. 10 T1D and 12 healthy subjects (ND), matched for BMI (23 ± 3 vs 26 ± 5 kg/m2) underwent a 180 min hyperinsulinemic (2 mU/kg TBW/min), hypoglycemic clamp (~3.3mM) under normoxic conditions (SpO2 98 ± 1%). T1D subjects did not report autonomic symptoms. [3‐3H] glucose was infused to measure glucose turnover. Results were compared using means of last forty minutes of clamp data. Statistical analyses were done using unpaired t‐tests and p<0.05 was considered significant.In the presence of matched glucose (3.3±0.1 vs.3.3±0.1 mM) and insulin concentrations (783±106 vs. 812±185 pM;p=0.66), counterregulatory hormonal responses epinephrine (274 ± 165 vs. 742 ± 279 pg/ml) and glucagon (30 ± 11 vs 105 ± 31pg/ml) to hypoglycemia were significantly lower (p<0.001) in T1D vs. ND respectively. The glucose infusion rate required to maintain hypoglycemia was significantly higher (36 ± 1 vs.28 ± 0 µmol/kg/min, p <0.001) and endogenous glucose production was significantly lower (10 ± 3 vs.14 ± 4 µmol/kg/min, p<0.05) in T1D vs. ND with unchanged insulin stimulated glucose uptake. We conclude that in T1D the CB sensitivity to hypoglycemia is impaired and may contribute to increased risk of hypoglycemia in these individuals. Future studies are required to evaluate CB response in hypoglycemia unaware individuals with T1D.Grant Funding Source: DK90541