scholarly journals Acute Exhaustive Exercise under Normoxic and Normobaric Hypoxic Conditions Differentially Regulates Angiogenic Biomarkers in Humans

Medicina ◽  
2021 ◽  
Vol 57 (7) ◽  
pp. 727
Author(s):  
Frank Suhr ◽  
Sarah Knuth ◽  
Silvia Achtzehn ◽  
Joachim Mester ◽  
Markus de Marees
Keyword(s):  
Extracellular Matrix ◽  
Matrix Metalloproteases ◽  
Short Term ◽  
Post Exercise ◽  
Exercise Interventions ◽  
Positive Effects ◽  
Hypoxic Conditions ◽  
Ecm Extracellular Matrix ◽  
And Performance ◽  
Angiogenic Biomarkers

Background and Objectives: Angiogenesis describes the outgrowth of new capillaries from already existing ones. Different biomarkers regulate this process. Physical exercise and hypoxia are key stimuli for the activation of different angiogenic molecules, such as the vascular endothelial growth factor (VEGF). matrix metalloproteases (MMPs)-2 and -9 or the extracellular matrix cleavage fragment endostatin. The present study aimed to investigate influences of short-term, intensive cycling exercise under both normoxic and normobaric hypoxic conditions on the mentioned parameters. Materials and Methods: Twelve male subjects (age: 23.3 ± 2.0 years) participated in the study. All subjects conducted four intensive cycling tests until individual exhaustion in a randomized order under the following conditions: normoxia, 2000 m, 3000 m and 4000 m above sea level. Blood samples were taken before (pre) and 10 min, 30 min, 60 min and 240 min post exercise and were analyzed by ELISA. Results: VEGF showed a significantly reduced concentration compared to the pre-value solely under 4000 m at 10 min post exercise. MMP-2 showed significantly reduced concentrations at 240 min post exercise under 4000 m. MMP-9 increased at 240 min post exercise under both 2000 m and 4000 m conditions. Endostatin was significantly increased at 10 min post exercise independently of the applied stimulus. Conclusions: The presented data show that intensive short-term exercise bouts facilitate the bioavailability of angiogenic, ECM (extracellular matrix)-related biomarkers. This finding is interesting for both health- and performance-related research as it demonstrates the positive effects of intensive short exercise interventions.

scholarly journals Bioreactor-Controlled Physoxia Regulates TGF-β Signaling to Alter Extracellular Matrix Synthesis by Human Chondrocytes

2019 ◽  
Vol 20 (7) ◽  
pp. 1715 ◽  
Author(s):  
Holger Jahr ◽  
Seval Gunes ◽  
Annika-Ricarda Kuhn ◽  
Sven Nebelung ◽  
Thomas Pufe
Keyword(s):  
Extracellular Matrix ◽  
Oxygen Tension ◽  
Molecular Mechanisms ◽  
Matrix Metalloproteases ◽  
Human Chondrocytes ◽  
Marker Genes ◽  
Matrix Synthesis ◽  
Altered Expression ◽  
Positive Effects ◽  
Marker Expression

Culturing articular chondrocytes under physiological oxygen tension exerts positive effects on their extracellular matrix synthesis. The underlying molecular mechanisms which enhance the chondrocytic phenotype are, however, still insufficiently elucidated. The TGF-β superfamily of growth factors, and the prototypic TGF-β isoforms in particular, are crucial in maintaining matrix homeostasis of these cells. We employed a feedback-controlled table-top bioreactor to investigate the role of TGF-β in microtissues of human chondrocytes over a wider range of physiological oxygen tensions (i.e., physoxia). We compared 1%, 2.5%, and 5% of partial oxygen pressure (pO2) to the ‘normoxic’ 20%. We confirmed physoxic conditions through the induction of marker genes (PHD3, VEGF) and oxygen tension-dependent chondrocytic markers (SOX9, COL2A1). We identified 2.5% pO2 as an oxygen tension optimally improving chondrocytic marker expression (ACAN, COL2A1), while suppressing de-differentiation markers (COL1A1, COL3A1). Expression of TGF-β isoform 2 (TGFB2) was, relatively, most responsive to 2.5% pO2, while all three isoforms were induced by physoxia. We found TGF-β receptors ALK1 and ALK5 to be regulated by oxygen tension on the mRNA and protein level. In addition, expression of type III co-receptors betaglycan and endoglin appeared to be regulated by oxygen tension as well. R-Smad signaling confirmed that physoxia divergently regulated phosphorylation of Smad1/5/8 and Smad2/3. Pharmacological inhibition of canonical ALK5-mediated signaling abrogated physoxia-induced COL2A1 and PAI-1 expression. Physoxia altered expression of hypertrophy markers and that of matrix metalloproteases and their activity, as well as expression ratios of specific proteins (Sp)/Krüppel-like transcription factor family members SP1 and SP3, proving a molecular concept of ECM marker regulation. Keeping oxygen levels tightly balanced within a physiological range is important for optimal chondrocytic marker expression. Our study provides novel insights into transcriptional regulations in chondrocytes under physoxic in vitro conditions and may contribute to improving future cell-based articular cartilage repair strategies.

scholarly journals Effects of Self-Talk Training on Competitive Anxiety, Self-Efficacy, Volitional Skills, and Performance: An Intervention Study with Junior Sub-Elite Athletes

Sports ◽  
2019 ◽  
Vol 7 (6) ◽  
pp. 148 ◽  
Author(s):  
Nadja Walter ◽  
Lucie Nikoleizig ◽  
Dorothee Alfermann
Keyword(s):  
Self Efficacy ◽  
Elite Athletes ◽  
Control Group ◽  
Short Term ◽  
Competitive Anxiety ◽  
Positive Effects ◽  
Self Talk ◽  
And Performance ◽  
The Impact

(1) Background: Self-talk (ST) is used to influence athletes’ thoughts, feelings, and behaviors. Samples of squad and competitive athletes are underrepresented, although research has proven the positive effects of ST in the context of sports. Thus, the present study focused on the impact of ST on psychological and performance outcomes of junior sub-elite athletes. (2) Methods: N = 117 athletes (55 females, 62 males; M = 16.0 years) were randomly assigned to either one of two experimental groups or to a control group (n = 30). The experimental groups received an ST intervention for either one week (n = 36) or eight weeks (n = 38), and the control group received no ST training. The dependent variables (competitive anxiety, volitional skills, self-efficacy, and coaches’ performance ratings) were assessed three times before and after the intervention. It was expected that (a) an ST intervention would reduce the competitive anxiety and increase volitional skills, self-efficacy, and performance; and, (b) long-term training would lead to higher effects than short-term training. (3) Results: As expected, ST training led to (less) somatic state anxiety and (higher) state self-confidence, self-optimization, self-efficacy, and performance. Additionally, long-term training was more effective than short-term training. (4) Conclusions: Targeted ST interventions may help to improve junior athletes’ psychological states and performance.

Growth, Maturation and Exercise During Youth—2016

2017 ◽  
Vol 29 (1) ◽  
pp. 3-7 ◽  
Author(s):  
Jaak Jürimäe
Keyword(s):  
Physical Activity ◽  
Physical Fitness ◽  
Short Term ◽  
Tennis Players ◽  
Positive Effects ◽  
Junior Tennis ◽  
And Performance ◽  
Time Varying Covariates ◽  
Methodological Paper ◽  
Selection Of

For The Year that Was—2016, I have selected three papers in the area of growth, maturation, and exercise during youth. The year of 2016 was a successful year and it was not an easy task to highlight the most significant publications in this specific area of pediatric exercise science. The first paper has been chosen because it provides, for the first time, the growth and maturational status of elite junior tennis players belonging to the top eight players in the National rankings in various ages and compares against population norms. It appeared that individual differences in growth and maturation contribute towards the selection of elite junior tennis players in both sexes, with a bias towards these athletes who are comparatively tall and heavy for their age already in younger ages. The second paper is a methodological paper and was selected because it provides a unique perspective on the use of different tracking coefficients to investigate short-term tracking of cardiorespiratory and performance-related physical fitness among adolescents during growth and maturation. Specifically, three distinct statistical approaches were applied in this paper: auto-correlations, mulitilevel modeling corrected tracking values for time-varying covariates and Cohen`s Kappa in order to identify group and individual tracking as well as individuals whose trajectories are unstable across time. This methodological paper demonstrated the importance of the selection of the statistical approach to monitor and describe short-term tracking of cardiorespiratory and performance-related physical fitness variables in adolescents during growth and maturation. The third selected paper provided some evidence that the consequence of physical activity during childhood can be far reaching as physical activity might not only promote health benefits but also have positive effects on adulthood earnings.

Undesirable Effects of Goal Setting on Perceived Fairness, Commitment, and Unethical Behavior

2018 ◽  
Vol 62 (2) ◽  
pp. 97-107 ◽  
Author(s):  
Nina Keith
Keyword(s):  
Goal Setting ◽  
Unethical Behavior ◽  
The United States ◽  
Goal Commitment ◽  
Management Technique ◽  
Long Term Effects ◽  
Perceived Fairness ◽  
Negative Effects ◽  
Positive Effects ◽  
And Performance

Abstract. The positive effects of goal setting on motivation and performance are among the most established findings of industrial–organizational psychology. Accordingly, goal setting is a common management technique. Lately, however, potential negative effects of goal-setting, for example, on unethical behavior, are increasingly being discussed. This research replicates and extends a laboratory experiment conducted in the United States. In one of three goal conditions (do-your-best goals, consistently high goals, increasingly high goals), 101 participants worked on a search task in five rounds. Half of them (transparency yes/no) were informed at the outset about goal development. We did not find the expected effects on unethical behavior but medium-to-large effects on subjective variables: Perceived fairness of goals and goal commitment were least favorable in the increasing-goal condition, particularly in later goal rounds. Results indicate that when designing goal-setting interventions, organizations may consider potential undesirable long-term effects.

Effect of leadership styles on organizational commitment and performance in small- and medium-sized enterprises in Iraqi Kurdistan

2020 ◽  
Vol 48 (9) ◽  
pp. 1-12
Author(s):  
Karwan Hamasalih Qadir ◽  
Mehmet Yeşiltaş
Keyword(s):  
Organizational Commitment ◽  
Organizational Performance ◽  
Leadership Styles ◽  
Chief Executive Officers ◽  
Chief Executive ◽  
Mediating Effect ◽  
Positive Effects ◽  
Iraqi Kurdistan ◽  
And Performance ◽  
Executive Officers

Since 2003 the number of small- and medium-sized enterprises (SMEs) has increased exponentially in Iraqi Kurdistan. To facilitate further growth the owners and chief executive officers of these enterprises have sought to improve their leadership skills. This study examined the effect of transactional and transformational leadership styles on organizational commitment and performance in Iraqi Kurdistan SMEs, and the mediating effect of organizational commitment in these relationships. We distributed 530 questionnaires and collected 400 valid responses (75% response rate) from 115 SME owners/chief executive officers and 285 employees. The results demonstrate there were positive effects of both types of leadership style on organizational performance. Further, the significant mediating effect of organizational commitment in both relationships shows the importance of this variable for leader effectiveness among entrepreneurs in Iraqi Kurdistan, and foreign entrepreneurs engaging in new businesses in the region.

scholarly journals Association of Cognitive Function Screening Results with Adherence and Performance in a Pedometer-Based Intervention

2021 ◽  
pp. 1-9
Author(s):  
Anoop Sheshadri ◽  
Piyawan Kittiskulnam ◽  
Cynthia Delgado ◽  
Rebecca L. Sudore ◽  
Jennifer C. Lai ◽  
...  
Keyword(s):  
Cognitive Impairment ◽  
Cognitive Function ◽  
Physical Performance ◽  
Mixed Model ◽  
Linear Mixed Model ◽  
Controlled Trial ◽  
Cognitive Status ◽  
Dialysis Patients ◽  
Exercise Interventions ◽  
And Performance

<b><i>Introduction:</i></b> A randomized, controlled trial of a pedometer-based walking intervention with weekly activity goals led to increased walking among dialysis patients. We examined whether impairment per cognitive function screening is associated with adherence and performance in the intervention. <b><i>Methods:</i></b> Thirty dialysis patients were randomly assigned to a 3-month pedometer-based intervention with weekly goals. Participants were administered the Telephone Interview of Cognitive Status (TICS), a test of global mental status. We examined the association of levels of impairment on the TICS (≥33: unimpaired, 26–32: ambiguous impairment, 21–25: mild cognitive impairment [MCI]) with adherence, achieving weekly goals, and increasing steps, physical performance (Short Physical Performance Battery, SPPB), and self-reported physical function (PF) through multivariable linear mixed-model and logistic regression analyses adjusted for age, sex, BMI, dialysis modality, baseline steps, baseline SPPB, and stroke status. <b><i>Results:</i></b> One-third of participants were unimpaired, and 13% had MCI. Participants with worse results on cognitive function screening missed more calls and completed fewer weekly goals than participants with better results. During the intervention, a worse result on cognitive function screening was associated with smaller increases in steps compared to those without impairment: (ambiguous: −620 [95% CI −174, −1,415], MCI: −1,653 [95% CI −120, −3,187]); less improvement in SPPB (ambiguous: −0.22 points [95% CI −0.08, −0.44], MCI: −0.45 [95% CI −0.13, −0.77]); and less improvement in PF (ambiguous: −4.0 points [95% CI −12.2, 4.1], MCI: −14.0 [95% CI −24.9, −3.1]). During the postintervention period, a worse result on cognitive function screening was associated with smaller increases in SPPB (ambiguous: −0.54 [95% CI −1.27, 0.19], MCI: −0.97 [95% CI −0.37, −1.58]) and PF (ambiguous: −3.3 [95% CI −6.5, −0.04], MCI: −10.5 [95% CI −18.7, −2.3]). <b><i>Discussion/Conclusion:</i></b> Participants with worse results on cognitive function screening had worse adherence and derived less benefit from this pedometer-based intervention. Future exercise interventions should be developed incorporating methods to address cognitive impairment, for example, by including caregivers when planning such interventions.

Effects of Short-Term Mission Trips on Recipients’ Self-Esteem and Readiness for Self-Directed Learning

2021 ◽  
pp. 009164712110115
Author(s):  
Charissa H. W. Wong ◽  
Li Neng Lee ◽  
Alberto Pérez Pereiro
Keyword(s):  
Self Esteem ◽  
Control Group ◽  
Short Term ◽  
Self Directed Learning ◽  
Positive Effects ◽  
Post Test ◽  
Quasi Experimental ◽  
Directed Learning ◽  
Group Post ◽  
Mission Trips

Short-term Christian overseas volunteer trips, also known as short-term mission trips (STMs), have become increasingly prevalent (Howell & Dorr, 2007). However, research on these programs has been limited. This quasi-experimental study adds to the literature by quantitatively measuring the effects of an STM from Singapore to Thailand. STM recipients’ ( n = 44) self-esteem and readiness for self-directed learning (RSDL) were compared across timepoints – pre-test, post-test, follow-up – and with a control group ( n = 50). It was hypothesized that recipients would experience an increase in self-esteem and RSDL such that their scores would be higher than the control group post-STM. Results provide partial support for the hypotheses; while improvements among recipients were either not significant (for self-esteem) or not long-lasting (for RSDL), recipients had higher scores than the control group post-STM. This suggests that STMs have some, albeit limited, positive effects. Recommendations for promoting greater and longer-lasting effects are offered.

Sign in / Sign up

Export Citation Format

Share Document