bluuebunny/crossref_metadata_2025_split huggingface dataset:
Low‐Flow‐Mediated Constriction is Reduced in Healthy Postmenopausal Women
Authors: Kuczmarski Andrew , Sebzda Kelly , Wenner Megan 
Published: June 2021

Vascular function declines in women after menopause, and has been characterized by a reduction in brachial artery flow‐mediated dilation (FMD). Low‐flow‐mediated constriction (L‐FMC) is an assessment of resting arterial tone that serves as a complementary measure of vascular function. Although L‐FMC has been shown to be reduced in certain diseased populations such as coronary artery disease, to our knowledge it is unknown if L‐FMC is altered with age/menopause. Accordingly, the purpose of this study was to test the hypothesis that postmenopausal women (PMW) have reduced L‐FMC values compared to young women (YW). We assessed vascular function in 16 PMW (59±1 years, 24±1 kg/m2) and 19 YW (21±1 years, 23±1 kg/m2). Longitudinal images of the brachial artery were acquired using ultrasound (GE Logic P5). A blood pressure cuff was placed just distal to the olecranon process and inflated to 200mmHg for five minutes. Images were recorded continuously during baseline (1‐minute), cuff occlusion (5‐ minutes), and cuff release (2‐minutes). L‐FMC was calculated as a percent change from baseline diameter to the average diameter during the last 30 seconds of cuff occlusion. FMD was calculated as a percent change from baseline diameter to peak diameter following cuff release. Total vessel reactivity was calculated as the sum of the absolute value of L‐FMC and FMD. All women were normotensive, although PMW had higher resting mean arterial pressure (PMW: 90±2 mmHg, YW: 82±2 mmHg; P<0.01). L‐FMC was reduced in PMW compared to YW (PMW: −1.67±0.36% vs YW: −2.84±0.35%; P=0.03). FMD was lower in PMW compared to YW (PMW: 5.47±0.54% vs YW: 7.33±0.53%; P=0.02). Total vessel reactivity was also lower in PMW (PMW: 7.32±0.67% vs YW: 10.17±0.57%; P<0.01). Consistent with previous findings, PMW have lower FMD values compared to YW. In addition, PMW also have reduced L‐FMC compared to YW. These findings suggest that L‐FMC may be a useful measure of vascular function with healthy aging.Support or Funding InformationSupported by: NIH Grant P20 GM 103446, U54 GM 104941, P20 GM113125, and University of Delaware Research Foundation.This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Human Foreskin Fibroblast Behavior in the Presence of 3D Collagen, Fibrin, and Calcium Phosphate
Authors: Eckhart Kyle , Kniseley Atherton , Bucci Brianna , Vaghasia Nikita , Tawil Bill 
Published: June 2021

3D modeling in cell‐based assays, provides an environment that mimics in vivo conditions. This allows for the examination of innate cellular behavior and aids in the development of next‐generation modeling and therapies. Cellular environments can be modeled using various constituents to manipulate the rigidity, porosity, and size of various 3D environments to observe cell characteristics in an environment similar to that from which they originated. The proliferation of Human Foreskin Fibroblasts (HFF‐1) were examined in a 3D collagen matrix with varying cell densities. Higher cell concentration within the 3D collagen matrix showed lower HFF‐1 cell proliferation. Furthermore, fibrin clots were used to mimic 3D microenvironments because of its biocompatibility and controllable biodegradability. Changing fibrinogen and thrombin concentrations provides a varying effect on the rigidity and porosity of a 3D environment and therefore affects the overall behavior of HFF‐1. There was an increase in fibrin bead size in the presence of cells with higher concentrations of fibrinogen and thrombin. To mimic a bone microenvironment, calcium phosphate (CaP) was introduced in increasing concentrations to support a rigid and structured environment. Increasing concentrations of CaP, resulted in an increase in the initial adhesion and a decrease in HFF‐1 proliferation over a 7‐day incubation period. Overall, cells in a 2D environment behave different than those in a 3D environment with varying components to imitate their in vivo conditions.Support or Funding InformationN/AThis abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Cytokine Responses to Cyclical Blood Flow Restriction Exercise
Authors: Sprick Justin , Romero Steven , Rickards Caroline 
Published: June 2021

IntroductionWe developed a novel adaptation of blood flow restriction exercise, cyclical blood flow restriction exercise (C‐BFRE), as a method to potentially augment the cardio‐protective effects associated with conventional exercise (CE) and remote ischemic preconditioning (RIPC). As the cytokines IL‐6 and IL‐10 have been implicated in mediating the acute cardio‐protection associated with both exercise training and RIPC when performed independently, we hypothesized that C‐BFRE would augment the systemic release of these factors compared to an acute bout of either CE or RIPC alone.Methods13 young healthy subjects (6M/7F, age 28±2 y) completed 3 experimental sessions separated by at least 1 month each. Aerobic exercise was performed via 40‐min of treadmill walking at 65–70% HRmax with (C‐BFRE) and without (CE) application of bilateral thigh cuffs inflated to 220 mmHg (4 × 5‐min inflation periods followed by 5‐min reperfusion periods). RIPC consisted of 4 × 5‐min thigh cuff inflation periods (220 mmHg) followed by 5‐min reperfusion periods in the absence of exercise. Venous blood samples (via an antecubital vein) were collected at baseline and immediately following completion of each protocol for analysis of IL‐6 and IL‐10 via multiplex ELISA.ResultsPlasma IL‐6 increased from baseline following CE (Pre, 0.26 ± 0.03 vs. Post, 0.40 ± 0.07 pg/ml; P=0.03) but not with C‐BFRE (Pre, 0.28 ± 0.05 vs. Post, 0.34 ± 0.07 pg/ml; P=0.75) or RIPC (Pre, 0.31 ± 0.04 vs. Post, 0.32 ± 0.03 pg/ml; P=1.0). There were no changes in plasma IL‐10 from pre‐ to post‐intervention for any of the three conditions (P=0.42 for main effect of time).DiscussionContrary to our hypothesis, we observed no change in plasma IL‐10 or IL‐6 with application of acute C‐BFRE. These findings suggest that the model of C‐BFRE utilized in this study does not augment the release of these cytokines in young healthy individuals. This may be due to the timing of the blood samples, the use of a standard occlusive pressure across all subjects, and the young, healthy subjects tested in this study. Future work should delineate the inflammatory response induced by C‐BFRE at more extended recovery time points, with use of individualized occlusive pressures, and in more clinically relevant populations in both acute and long term settings.Support or Funding InformationFunding for this study was provided, in part, by training fellowships awarded to Justin Sprick through a NIH‐supported Neurobiology of Aging Training Grant (T32 AG020494, PI: Singh, M), and a Ruth L. Kirchstein NRSA F31 Predoctoral Fellowship (1F31HL134242‐01A1; PI: Sprick, JD), a UNTHSC Faculty Research Pilot Grant (PI: Rickards, CA), and a Texas Chapter of the American College of Sports Medicine (TACSM) Student Research Development Award (PI: Sprick, JD).This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Effect of Age and Acute Exercise on Circulating Endostatin
Authors: Temperley McKenzie K. , Mardis Benjamin R. , Iwamoto Erika , Bock Joshua M , Casey Darren P. , Luttrell Meredith 
Published: June 2021

BACKGROUNDEndostatin may have both angiogenic and angiostatic effects in vivo, although angiostatic effects appear to predominate. It has been reported that circulating levels of endostatin increase after acute exercise in young adults; however, it is unclear whether healthy older adults exhibit a similar response.PURPOSEThe purpose of this study was to determine the effect of age on changes in serum endostatin concentration following an acute bout of dynamic exercise.METHODSTen young (25 ± 1 years, 5M/5F) and nine older (68 ± 2 years, 4M, 5F) healthy but sedentary to recreationally active adults completed a single 45‐minute bout of submaximal cycle ergometer exercise at 60 – 65% of their age‐predicted maximal heart rate. Venous blood samples were obtained prior to (PREX), immediately post‐ (POSTX0), and at three hours post‐exercise (POSTX3). Serum concentrations of endostatin were analyzed at each time point using an enzyme‐linked immunosorbent assay. Absolute protein concentrations at each time point and fold‐change from PREX concentrations are reported.RESULTSThere was no difference in PREX serum endostatin concentration between young (136.2 ± 18.48 pg/mL) and older adults (125.9 ± 11.48 pg/mL) (p=0.81). Additionally, there was no age effect on absolute endostatin concentrations at POSTX0 and POSTX3 (p = 0.06 for interaction). However, when comparing the fold‐change in endostatin concentration after exercise, there was a significant interaction (p = 0.01) between age and POSTX0 to POSTX3 time point. The main effects (time, age) were not significant. Simple main effects analysis revealed a difference in fold‐change in concentration of endostatin from PREX in older (p = 0.02) but not younger (p = 0.80) adults from POSTX0 to POSTX3.CONCLUSIONSOur data suggests there is no difference in either PREX serum endostatin concentrations between young and older adults. However, older adults may have a different temporal response in serum endostatin following a single bout of moderate intensity dynamic exercise compared to young adults.Support or Funding InformationResearch Support: University of Iowa Carver College of Medicine FUTURE in Biomedicine Program (MJL, BRM, DPC).This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Aerobic Exercise and Environmental Heat Stress as Adjuvants to Seasonal Influenza Vaccine
Authors: Colburn Abigail , Wright Skylar , Lopez Virgilio , Giersch Gabrielle , Belval Luke , Hosokawa Yuri , Huggins Robert A , Armstrong Lawrence , Casa Douglas J , Lee Elaine C 
Published: June 2021

Influenza strain diversity and variability and individual immune health contribute to reduced vaccine efficacy. Among adjuvants that enhance vaccine effectiveness, several studies have examined the relationship between acute exercise stress and influenza vaccination immune responses in humans. It is proposed that acute bouts of stress enhance immune response, but optimal intervention, timing of intervention, and mechanisms have yet to be identified. As Toll‐like receptor (TLR) agonists enhance innate immune responses and support development of chronic humoral responses, exercise induced release of the TLR4 ligand lipopolysaccharide (LPS) into circulation may be a mechanism for benefit of pre‐vaccine exercise. This study aimed to assess the effects of exercise and exercise‐heat stress completed before seasonal influenza vaccination (IV) on short‐ and long‐term immune responses. Thirty‐four males (body mass, 77.41±12.48kg; age, 21.5±4.4y; maximal aerobic capacity (VO2max), 43.53±8.24mL/kg/min) were randomized into 1 of 3 groups: no exercise (NE, n=12) or 60 minutes of 60%VO2max exercise with (MEH, n=11) or without (ME, n=11) environmental heat stress. Exercise and baseline blood samples were completed 25.11±5.92h before IV, and subsequent blood samples were collected 23.45±6.13h, 13.06±2.96d, and 29.54±3.73d following IV. Exercise environmental conditions were different between ME and MEH, respectively (average wet bulb globe temperature, 32.91±2.67°C, 41.21±2.88°C; p<0.001), but physiological stress was similar (average rectal temperature, 37.30±0.48°C, 27.61±1.36°C, p=0.513; heart rate, 114±105bpm, 118±105bpm, p=0.103) due to controlled exercise intensity. On‐going research will utilize hemagglutinin inhibition, cortisol, and LPS assays to quantify virus‐specific antibody responses, stress, and TLR4 activation respectively. Understanding innate and humoral responses will elucidate the potential of exercise and exercise‐heat stressors as adjuvants for IV.Support or Funding InformationNew investigator start‐up, InCHIP Interdisciplinary Seed GrantThis abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Perceptual Responses to Exercise Heat‐Stress in Smokers versus Non‐Smokers
Authors: Kennedy Kallean Joan , Caldwell Aaron , Garcia Nathanael , Upton Martha , Hartzell Kristen , Ganio Matthew 
Published: June 2021

Physiological and psychological/mental stress occurs as individuals undergo exercise‐ heat stress. The latter can include perceptual measures, feelings of mood, and cognition performance. Decrements in these may lead to a decrease in productivity and motivation. Prior work suggests that smokers and non‐smokers have physiological differences, thus it is possible that smokers perceive exercise heat‐stress differently. It is important to understand how smokers “feel” during heat stress, especially when they are being physically active.PurposeThe purpose of this pilot study was to determine whether exercise heat stress has negative cognitive and perceptual effects on smokers versus non‐smokers.MethodsThree current male smokers (SMK: 20.6 ± 2.3 yr; 6 ± 1.7 cigarettes/day; 86.6 ± 10.2 kg; 21 ± 3.1% body fat) and 3 non‐smokers (N‐SMK: 24.6 ± 5.1 yr; 80.3 ± 3.6kg; 20.7 ± 8.2% body fat) participated in an experimental trial consisting of subjects performing 60 total minutes of cycling. Specifically, there were three 20‐minute exercise periods with two 20 minute rest periods in between each exercise bout. Participants cycled at a target metabolic heat production of 6 watts/kg in an environmental chamber at 40°C, 35 % relative humidity. The subject's internal temperature (Trec ) via rectal thermistor, mean body temperature (Tbody), heart rate and perceptual measures were collected every 5 and 15 minutes throughout each exercise and rest periods. Perceptual measures included perceived exertion, thirst, thermal sensation, muscle pain, motivation to continue, feeling and comfort.ResultsDuring the experimental trial, Trec at baseline for SMK and N‐SMK was 37.36±0.15 and 37.43±0.7°C, respectively; at the end of exercise (i.e., min 60) Trec was 38.03±0.2 and 38.34±0.7°C. Tbody for SMK and N‐SMK at the end of exercise was 39.5±0.16 and 39.7±0.7°C, respectively. HR was similar in SMK (132 ± 16.7 bpm) vs. N‐SMK (133±19.1 bpm). At the end of the last exercise bout the final perceptual ratings for SMK and N‐SMK were 10±3 and 11±1 for RPE, 4±2 and 4±3 for Thirst, 4.7±0.6 and 5.6±0.3 for Thermal, 1.3±0.6 and 1.2±0.8 for Muscle Pain, 4±2 and 4±1 for motivation to continue, 3±2 and 2±1 and for feeling and 2±1 and 2±1 for comfort.ConclusionIn this pilot study, when exercising at a similar relative rate of metabolic heat production, smokers had similar physiological responses. Likewise, the perceptual variables obtained were also similar between smokers and non‐smokers. This has implications for occupational settings in which smokers are heat stressed and trying to complete tasks that involve cognitive thought processes.Support or Funding InformationFunding provided by: Arkansas Department of Higher Education and the University of ArkansasThis abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Effects of Caffeine and Menstrual Phase on Performance of Female Athletes during Heat Stress
Authors: Rutherford Maura McLean , Palmer Matthew S 
Published: June 2021

The effects of menstrual phase on athletic performance are controversial, but commonly ascribed to temperature‐related impairments in physical and cognitive performances. Caffeine stimulates the CNS to enhance endurance performance, and while effects persist for men exercising in the heat, little work has been done with women. Moreover, many female athletes use oral contraceptive steroids (OCS) to regulate their menstrual cycles, which may pronounce the effects of caffeine. The purpose of this study was to evaluate the effects of menstrual phase and caffeine supplementation on physical and cognitive performances of women exercising in the heat. Six recreationally active female subjects (20.3 ± 1.6 yr, 1.67 ± 0.05 m, 69.3 ± 5.5 kg, 49.8 ± 3.3 ml·kg−1·min−1) concurrently taking monophasic OCS volunteered for this study. Each subject completed four trials: in the early follicular (EF, days 3–5) and midfollicuar (MF, days 19–21) phases of the menstrual cycle, after administration of either a placebo (P, corn starch) or caffeine (C, 5.5 mg/kg). Placebo and caffeine were administered in 355 mL “diet” cranberry drink (0 kcal), 1 hour prior to performing a self‐paced 5km time trial (TT) in the heat (29.6 ± 0.1°C, 55.8 ± 1.5 % relative humidity). Heart rate was recorded continuously and RPE was collected at 1‐km intervals. Oral temperature, Profile of Mood States (POMS) questionnaires and 2 tests of reaction and cognition (FitLight) were performed immediately prior to and following exercise. Time trial performance was improved in the EF‐C trial vs. EF‐P, ML‐C and ML‐P (1883 ± 203 vs. 1918 ± 224, 1898 ± 196, 1907 ± 205 seconds). Oral temperature tended to be elevated post‐TT in EF‐C vs. all other trials (37.4 vs. ~37.0 °C), while HR AUC tended to be decreased in the EF trials (5404 ± 167 vs. 5544 ± 181 beats, p = 0.09). The POMS Fatigue index was significantly higher post‐TT in the ML‐C trial (15.0 ± 1.9 vs 12.7 ± 0.4, 10.8 ± 1.1, ±11.2 ± 1.0). RPE and cognitive test responses were not different between trials. In heat stress, caffeine improves time trial performance in the EF phase despite an increased post‐exercise oral temperature. While heart rate response tended to be lower in the EF phase, no differences were observed in any other physical or cognitive performance measure between trials.Support or Funding InformationScotia Scholars Award, Nova Scotia Health Research FoundationThis abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Abrin, a Type II Ribosome Inactivating Protein: Differential Cytotoxicity and Development of the Vaccine Against its Lethality
Authors: Tiwari Vinita , Karande Anjali A 
Published: June 2021

The plant toxin, Abrin, a type II ribosome inactivating protein, is extremely lethal, the human fatal dose being ~1 μg/kg body weight. Abrin has been classified as an agent for bioterrorism, which is of huge concern. On the other hand, the high toxic property of abrin has been employed in generating immunotoxins, where its toxin moiety is conjugated to cell surface marker specific antibodies for cell targeted killing.Different cell types exhibit variable levels of sensitivity to abrin toxicity. To gain insights into this, two cell lines requiring strikingly different IC50 of abrin for inactivating ribosomes were studied. In KB cells, the abrin A chain was found to be sequestered from the cytoplasm into the nucleus by a protein called Brain acid soluble protein (BASP‐1), enabling the cells to resist abrin‐mediated inhibition of protein synthesis. In Ovcar‐3 cells that express negligible amounts of BASP‐1, the A chain remains in the cytosol to exert its N‐glycosidase activity, therefore succumb to low concentrations of abrin. In contrast, when the apoptosis inducing activity of abrin was examined, both the cells showed comparable apoptotic population. Employing conjugates of the wild type and active site mutant ABA with the ricin B chain it was found that abrin‐induced apoptosis was dependent on inhibition of protein synthesis leading to ER‐stress in Ovcar‐3 cells, but not in KB cells. Direct DNA damage caused by the abrin A chain sequestered in the nucleus might be contributing to the apoptosis in KB cells.Towards establishing vaccines to counteract abrin‐induced lethality, we designed a recombinant chimeric protein of Abrin A chain and Abrus precatorius agglutinin A chain on the basis of epitope specificity. Abrin part of the chimera contains the epitope for the only two neutralizing antibodies; D6F10 and A7C4, reported against abrin till now. Importantly, the chimera harboured no enzymatic activity and was found to protect 100 % mice from abrin challenge upto 45 X LD50 dose. Thus the chimera appears to be potential vaccine against abrin induced lethality.This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Compensatory regulation of Extracellular Pyrophosphate Metabolism in Vascular Smooth Muscle Cells during Early Calcification
Authors: Bellosta Ricardo Villa 
Published: June 2021

Hydroxyapatitedeposition on the medial layer of the aortic walls is the hallmark of vascularcalcification and the most common complication in aging individuals andin patients with diabetes and those undergoing hemodialysis. Hyperphosphatemiais the main risk factor for vascular calcification and extracellularpyrophosphate (ePPi) is a potent physicochemical inhibitor of hydroxyapatitecrystal formation. Most ePPi is degraded to inorganic phosphate (Pi) by tissue non‐specific alkaline phosphatate (TNAP) in the aortic wall. Moreover, ePPiis generated enzymatically by hydrolysis of extracellular ATP by the enzyme ectonucleotidepyrophosphatase/phosphodiesterase 1 (eNPP1). Extracellular ATP is alsohydrolyzed by the ectonucleoside triphosphate diphosphohydrolase 1 (eNPTD1),releasing Pi. This study analyzed changes in extracellularpyrophosphate metabolism during the calcification process.Pi‐induced calcification of ex vivo‐culturedaortic rings resulted in calcium accumulation after 7 days. This accumulation was enhanced when aortic walls were devitalized (118.9 μmolCa2+/gaorta vs. 433 μmolCa2+/g aorta, respectively). Bone morphogenic protein 2 (BMP2)expression was associated with calcium accumulation in Pi‐induced calcificationin cultured aortic rings, as well as in cultured vascular smooth muscle cells (VSMCs);and in calcitriol‐induced calcification in rats. Hydroxyapatite dose‐dependently induced BMP2 overexpression in VSMCs. TNAP mRNA levels and activity were found to be downregulated in early phases and upregulated in later phases of calcification in all three models studied. eNPP1 increased from early to later phases of calcification, whereas eNTPD1 was downregulated during later phases. Synthesis of pyrophosphate in VSMCs increased significantly over time, in all three models studied. Because the rate of pyrophosphate hydrolysis was100 times slower than the rate of ATP hydrolysis (Vmax values of 56.7 and 5016 pmol*mg−1*min−1,respectively, and Km values of 215 μmol/L pyrophosphate and 512 μmol/L ATP, respectively), pyrophosphate synthesis is determined mainly by the ratio ofeNPP1 to eNTPD1 activity. Hydroxyapatite also induces increments both in TNAP and eNPP1/eNTPD1 ratio in VSMCs.These findings indicate that pyrophosphate synthesis increases in VSMCs during early calcification. Moreover, BMP2 may be a good marker of calcification, especially during early phases. By contrast, TNAP expression is not a good marker of calcification due to its regulation by various stimuli.Support or Funding InformationThis study was supported by grant SAF‐2014‐60699‐JIN from the Spanish Mini sterio deEconomía y Competitividad (MINECO).This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.