scholarly journals OR02-02 Possible Age and Time-Of-Day Differences in the Hypothalamo-Pituitary-Testicular, and Adrenal, Response to Total Overnight Sleep Restriction

2020 ◽  
Vol 4 (Supplement_1) ◽  
Author(s):  
Peter Y Liu ◽  
Paul Takahashi ◽  
Rebecca Yang ◽  
Ali Iranmanesh ◽  
Johannes D Veldhuis
Keyword(s):  
Repeated Measures ◽  
Statistical Significance ◽  
Approximate Entropy ◽  
Older Men ◽  
Pulse Frequency ◽  
Time Of Day ◽  
Regulatory Control ◽  
Sleep Restriction ◽  
Adrenal Response ◽  
Entropy Statistics

Abstract Introduction: In young men, sleep restriction decreases testosterone and increases afternoon cortisol, leading to anabolic-catabolic imbalance, insulin resistance and metabolic, neurocognitive, reproductive, and other adverse effects. Age-related differences in the hypothalamo-pituitary-testicular/adrenal response to sleep restriction could expose older individuals to greater or lesser risk, but this possibility has not been previously studied. Subjects and Methods: Thirty-five healthy young and older men aged 18-30y (n=17) and 60-80y (n=18), underwent blood sampling in the Mayo Clinic Center for Clinical and Translational Science every 10 minutes for 24 hours from 6PM-6PM under two conditions in random order spaced at least 3 weeks apart: awake (no sleep) or sleep (from 10PM to 6AM). Blood was assayed for LH, testosterone (T) and cortisol (F), and then analyzed by automated mathematical deconvolution and with cross approximate entropy statistics to determine hormone secretion and hormone synchrony, respectively. Statistical significance was construed by repeated measures ANOVA using a full factorial model that included age, sleep and the interaction. Results: Sleep deprivation had multiple effects on 24-hour (6PM-6PM) Te secretion with significant reductions in mean concentrations, basal, total and pulsatile secretion, and pulse frequency (each P<0.05), in the absence of detectable changes in LH. These effects were most apparent in older men and differed according to age for some parameters: pulsatile Te secretion (P=0.03) and T pulse frequency (P=0.02). Time-of-day analyses revealed that sleep restriction significantly reduced Te in the morning (6AM-9AM) and afternoon (3PM-6PM), reduced LH in the morning, and increased F in the afternoon, particularly in older men. Cross-approximate entropy statistics showed that sleep restriction enforced greater LH-Te and Te-LH joint synchrony in the morning (P<0.05 for each), but not in the afternoon. Conclusion: Sleep restriction decreases morning LH secretion, morning and afternoon Te secretion, and increases afternoon F secretion, especially in older men. This combination of findings could plausibly cause metabolic and reproductive ill-health when accumulated over decades of life, and may explain how chronic sleep loss contributes to metabolic and reproductive diseases that are more prevalent in older men. These preliminary data also suggest a time-of-day dependent uncoupling of the regulatory control of the testicular axis, and of cortisol secretion. Direct verification by interventions that manipulate hormones during the morning and late afternoon in appropriately matched cohorts of young and older men are now required.

scholarly journals Age and time-of-day differences in the hypothalamo–pituitary–testicular, and adrenal, response to total overnight sleep deprivation

SLEEP ◽  
2020 ◽  
Vol 43 (7) ◽  
Author(s):  
Peter Y Liu ◽  
Paul Y Takahashi ◽  
Rebecca J Yang ◽  
Ali Iranmanesh ◽  
Johannes D Veldhuis
Keyword(s):  
Sleep Deprivation ◽  
Older Men ◽  
Pulse Frequency ◽  
Time Of Day ◽  
Regulatory Control ◽  
Sleep Restriction ◽  
Older Individuals ◽  
Deconvolution Analysis ◽  
Age Related ◽  
Adrenal Response

Abstract Study Objectives In young men, sleep restriction decreases testosterone (Te) and increases afternoon cortisol (F), leading to anabolic–catabolic imbalance, insulin resistance, and other andrological health consequences. Age-related differences in the hypothalamo–pituitary–testicular/adrenal response to sleep restriction could expose older individuals to greater or lesser risk. We aimed to evaluate and compare the 24-h and time-of-day effect of sleep restriction on F, luteinizing hormone (LH), and Te in young and older men. Methods Thirty-five healthy men, aged 18–30 (n = 17) and 60–80 (n =18) years, underwent overnight sleep deprivation (complete nighttime wakefulness) or nighttime sleep (10 pm to 6 am) with concurrent 10-min blood sampling in a prospectively randomized crossover study. F, LH, and Te secretion were calculated by deconvolution analysis. Results Sleep deprivation had multiple effects on 24-h Te secretion with significant reductions in mean concentrations, basal, total and pulsatile secretion, and pulse frequency (each p < 0.05), in the absence of detectable changes in LH. These effects were most apparent in older men and differed according to age for some parameters: pulsatile Te secretion (p = 0.03) and Te pulse frequency (p = 0.02). Time-of-day analyses revealed that sleep restriction significantly reduced Te in the morning and afternoon, reduced LH in the morning in both age groups, and increased F in the afternoon in older men. Conclusions These data suggest a time-of-day dependent uncoupling of the regulatory control of the testicular axis and of F secretion. Future studies will need to directly verify these regulatory possibilities specifically and separately in young and older men. Clinical Trial Not applicable.

Gingival Health of Porcelain Laminate Veneered Teeth: A Retrospective Assessment

2019 ◽  
Vol 44 (5) ◽  
pp. 452-458 ◽  
Author(s):  
R Arif ◽  
JB Dennison ◽  
D Garcia ◽  
P Yaman
Keyword(s):  
Repeated Measures ◽  
Gingival Crevicular Fluid ◽  
Statistical Significance ◽  
Fluid Collection ◽  
Gingival Recession ◽  
Gingival Health ◽  
Long Term Effect ◽  
The Mean ◽  
Crevicular Fluid

SUMMARY Statement of Problem: The long-term effect of the presence of porcelain laminate veneers (PLVs) on the health of the surrounding gingival issues is not available in the restorative literature. Purpose: To assess the long-term effect of PLVs on the health of the surrounding gingival tissues. A secondary aim was to correlate gingival crevicular fluid (GCF) scores with clinical parameters used for gingival health assessment in teeth treated with PLVs. Methods and Materials: Patients who received PLVs placed at the Graduate Restorative Clinic within a seven- to 14-year period were recalled for clinical evaluations. Periodontal measurements including gingival index (GI), periodontal pocket depth (PPD), gingival recession (GR), and clinical attachment level (CAL) were measured using a standard probe and indices. Gingival Crevicular Fluid (GCF) was measured with a Periotron machine (Periotron 8000, Oraflow Inc), using Periopaper (Periopaper Gingival Fluid Collection Strip, Oraflow Inc.) for fluid collection. Photographs of any observed clinical defect were taken. Data were tabulated using Excel 2010 (Microsoft Corp). Statistical analysis for all descriptive statistics was performed using SPSS 21 (SPSS Software, IBM Corp.) and Stata SE 13 (Stata Software, StataCorp). Repeated-measures analysis of variance (ANOVA) was done to test for statistical significance of the mean pocket depths between the restored and unrestored surfaces of the veneered teeth. The significance level for all tests was p<0.05. Pearson's correlation coefficient was performed for testing statistical significance between GCF and GI and between GCF and PPD. Results: The frequency distribution of the GI included 47 PLVs (43%) with normal gingiva, 16 (15%) with mild inflammation, and 46 (42%) with moderate inflammation and bleeding on probing. The average PPD on the facial surface of the maxillary and mandibular PLVs was 2.17 mm and 2.16 mm, respectively. On the lingual surface, the average PPD was 2.10 mm for maxillary and 2.22 mm for mandibular PLVs. Gingival recession was seen in 27% of the evaluated PLVs. The repeated-measures ANOVA revealed p≥0.136, showing no statistical difference in the mean pocket depths between restored facial and unrestored lingual surfaces of the veneered teeth. A moderate correlation (r=0.407) was found between GCF and GI, which was significant at p<0.001. No correlation (r=0.124) was found between GCF and PPD, which was not significant at p=0.197. Conclusions: Gingival response to the evaluated PLVs was in the satisfactory range, with overall GI scores ranging between normal and moderate inflammation, pocket depths ranging from 1 to 2 mm, and recession present in 27% of the evaluated PLVs. No statistically significant difference was found between the mean pocket depths of the restored and unrestored surfaces of veneered teeth (p≥0.136). A moderate correlation was found between GCF and GI.

Vertical and horizontal barbell kinematics indicate differences in mechanical advantage between using an arched or flat back posture in the barbell bench press exercise

2021 ◽  
pp. 174795412098295
Author(s):  
Brendan L Pinto ◽  
Clark R Dickerson
Keyword(s):  
Repeated Measures ◽  
Bench Press ◽  
Glenohumeral Joint ◽  
Statistical Significance ◽  
Vertical Displacement ◽  
Moment Arm ◽  
Mechanical Advantage ◽  
Strength Performance ◽  
Flat Back ◽  
And Training

Employing an arched back posture during the bench press exercise is increasingly popular. Vertical displacement of the barbell is commonly believed to be the key difference influencing strength performance between an arched and flat back bench press technique. However, comparisons between these back postures using a free weight barbell are lacking. Directly comparing performance between each posture is confounded by many variables such as proficiency and fatigue. This investigation aimed to investigate whether changing back posture alone can influence barbell kinematics, to indirectly assess potential performance differences. Twenty males performed one repetition of the bench press exercise using either an arched or flat back posture, at 25%, 50% and 75% of their one repetition maximum, in a repeated measures study design. Statistical significance was considered at p < 0.05. Changing back posture alone, reduced vertical displacement (approximately 11% average difference across all load conditions) and barbell to glenohumeral joint moment arm (approximately 20% difference) in the arched posture compared to the flat posture. These changes occurred without any specific cueing of the barbell motion and may increase the potential for lifting higher loads and decrease cumulative joint exposure. Additional cueing and training may be required to maximize the mechanical advantage available with each back posture. The arched posture appears to have an increased potential for further improvements in vertical displacement and moment arm through specific cueing. Future comparisons should consider if each back posture’s potential mechanical advantage has been maximized when assessing differences between techniques.

scholarly journals HRV analysis: undependability of approximate entropy at locating optimum complexity in malnourished children

2021 ◽  
pp. 1-6
Author(s):  
David M. Garner ◽  
Gláucia S. Barreto ◽  
Vitor E. Valenti ◽  
Franciele M. Vanderlei ◽  
Andrey A. Porto ◽  
...  
Keyword(s):  
Statistical Significance ◽  
Accurate Determination ◽  
Approximate Entropy ◽  
Effect Sizes ◽  
Potential Hazard ◽  
Autonomic Modulation ◽  
Embedding Dimension ◽  
Malnourished Children ◽  
Hrv Analysis

Abstract Introduction: Approximate Entropy is an extensively enforced metric to evaluate chaotic responses and irregularities of RR intervals sourced from an eletrocardiogram. However, to estimate their responses, it has one major problem – the accurate determination of tolerances and embedding dimensions. So, we aimed to overt this potential hazard by calculating numerous alternatives to detect their optimality in malnourished children. Materials and methods: We evaluated 70 subjects split equally: malnourished children and controls. To estimate autonomic modulation, the heart rate was measured lacking any physical, sensory or pharmacologic stimuli. In the time series attained, Approximate Entropy was computed for tolerance (0.1→0.5 in intervals of 0.1) and embedding dimension (1→5 in intervals of 1) and the statistical significances between the groups by their Cohen’s ds and Hedges’s gs were totalled. Results: The uppermost value of statistical significance accomplished for the effect sizes for any of the combinations was −0.2897 (Cohen’s ds) and −0.2865 (Hedges’s gs). This was achieved with embedding dimension = 5 and tolerance = 0.3. Conclusions: Approximate Entropy was able to identify a reduction in chaotic response via malnourished children. The best values of embedding dimension and tolerance of the Approximate Entropy to identify malnourished children were, respectively, embedding dimension = 5 and embedding tolerance = 0.3. Nevertheless, Approximate Entropy is still an unreliable mathematical marker to regulate this.

scholarly journals Adolescent Pitcher Fatigue: Ulnar Collateral Ligament Stress, Flexor-Pronator Mass Energy Depletion, and Correlation to Pitch Count

2021 ◽  
Vol 9 (7_suppl4) ◽  
pp. 2325967121S0024
Author(s):  
Manuel Schubert ◽  
Tariq Awan ◽  
Aaron Sciascia ◽  
Emily Pacheco ◽  
Jennifer DeMink ◽  
...  
Keyword(s):  
Grip Strength ◽  
Muscle Glycogen ◽  
Repeated Measures ◽  
Statistical Significance ◽  
Ulnar Collateral Ligament ◽  
Glycogen Storage ◽  
Collateral Ligament ◽  
Time Points ◽  
Subjective Fatigue ◽  
Forearm Flexor

Objectives: There has been a rise in elbow ulnar collateral ligament (UCL) injuries in youth pitchers over recent years. With forearm flexor-pronator mass fatigue, the dynamic stability provided could be diminished placing greater stress on the UCL. Pitch count limits have been instituted in an attempt to help curtail this rise in throwing injuries, especially in youth athletes. In order to provide more objective data regarding current pitch count limits for youth pitchers, the purpose of this pilot study was to evaluate for potential fatigue of the flexor-pronator mass by assessing changes in medial elbow laxity, noninvasively characterizing changes in muscle glycogen storage within the forearm flexor-pronator mass, and evaluating changes in subjective fatigue, strength, range of motion (ROM), pitching velocity, and accuracy with increasing number of pitches thrown by 10-year-old pitchers up to their recommended 75 pitch count limit. Methods: After appropriate power analysis, male pitchers 10 years of age were recruited for the study (n=22). Pitchers threw a total of 75 pitches divided into sets of 25 pitches, with standardized periods of rest in between throws and sets to best simulate a game. Bilateral medial elbow laxity was measured by applying 10 decanewtons of valgus force with a standardized stress device and utilizing ultrasound imaging (Figures 1A-B) prior to pitching and after each pitching set. The change in medial ulnohumeral joint distance (Figure 1C) after stress was applied was calculated from baseline without stress. Relative changes in muscle glycogen storage, detected as changes in echogenicity, within the flexor carpi radialis (FCR) and the flexor digitorum superficialis (FDS)/flexor carpi ulnaris (FCU) muscles were measured non-invasively with ultrasound-based software (Figures 1D-E) and recorded as fuel percentile. Repeated measures analysis of variance and post-hoc testing were used to determine statistical significance (alpha=0.05). Results: There were no significant differences in medial elbow laxity between arms or time points. There was a trend for similar decline in FCR fuel percentile values between each arm, indicating relative decreases in glycogen storage bilaterally. However, only the throwing arm demonstrated a statistically significant decline in fuel percentile from baseline to after 75 pitches (p=0.05). There were no statistically significant differences across time points for FDS/FCU fuel percentile values. Fatigue measurements for both arms were significantly higher at all time points compared to baseline (p≤0.03). Grip strength of the dominant arm after 75 pitches was significantly decreased compared to after 25 pitches (p=0.02). There were no statistically significant changes in other strength measurements, ROM, velocity, or accuracy between all time points. Conclusions: By the recommended 75 pitch count limit in 10-year-olds, subjective fatigue and a decrease in grip strength had occurred. Furthermore, relative glycogen storage of the flexor-pronator mass of the throwing arm decreased between pitching 50 to 75 pitches, but without an increase in medial elbow gapping. This study provides a foundation and raises questions for further objective testing of physiologic changes that occur throughout increasing pitching to better guide pitch count limits and ensure the safety of young athletes

Body Composition Modifications Due to the “Search, Rescue and Survival Training” in Male Military Firefighter Cadets

2021 ◽  
Author(s):  
Thiago Ramos de Barros ◽  
Verônica Pinto Salerno ◽  
Thalita Ponce ◽  
Míriam Raquel Meira Mainenti
Keyword(s):  
Body Composition ◽  
Body Weight ◽  
Repeated Measures ◽  
Food Restriction ◽  
Physical Exertion ◽  
High Energy ◽  
The Body ◽  
Fat Free Mass ◽  
Sleep Restriction ◽  
Fat Percentage

ABSTRACT Introduction To train and prepare cadets for a career as firefighters in Rio de Janeiro, the second-year students of the Officers Training Course are submitted to a Search, Rescue, and Survival Training (SRST) course, which is characterized by long periods of high physical exertion and sleep restriction during a 9-day instruction module, and food restriction during a 7-day survival module. The present study investigated changes in the body composition of 39 male cadets submitted to SRST during training and 4 weeks of recovery with no restrictions in food consumption. Materials and Methods Each cadet was evaluated by anthropometric measurements at six time points: pre-SRST; after the first module; after the second module; and after 1, 2, and 4 weeks of recovery. Measurements included body girths and skinfolds, to estimate trunk (chest and waist) and limbs (arm and thigh) dimensions, as well as body composition. Repeated measures ANOVA and Friedman test were applied (depending on each data distribution). Results Statistically significant decreases in body weight (76.2; 69.8-87.2 to 63.9; 58.9-73.5 kg) and fat free mass (FFM, 69.2; 63.7-77.2 to 60.1; 56.2-68.0 kg) were observed following the second module of SRST. Following a single week of recovery, the FFM returned to pre-SRST values. Body weight returned to pre-training levels in 2 weeks. Body fat percentage and mass also significantly decreased during SRST (9.0; 7.7-12.3 to 6.5; 5.1-9.3% and 6.9; 5.6-10.0 to 6.9; 5.6-10.0 kg, respectively), which showed a slower and more gradual recovery that reached pre-SRST values after 4 weeks. The girths of arm, thigh, chest and waist significantly decreased due to SRST. The girths of the limbs (arm and thigh) returned to pre-training values after one month of recovery, while the girths of the trunk (chest and waist) did not return to pre-SRST values during the study period. Conclusions The findings suggest that men who experience periods of high energy demands and sleep restriction followed by a period of food restriction will endure unavoidable physical consequences that can be mostly reversed by a 1-month recovery.

Construct Stability of C2 Replacement Strategies

2003 ◽  
Author(s):  
Christian M. Puttlitz ◽  
Robert P. Melcher ◽  
Vedat Deviren ◽  
Dezsoe Jeszenszky ◽  
Ju¨rgen Harms
Keyword(s):  
Repeated Measures ◽  
Posterior Instrumentation ◽  
Statistical Significance ◽  
Axial Rotation ◽  
Posterior Fixation ◽  
Camera Motion ◽  
Anterior Plate ◽  
Intact Specimen ◽  
Strut Graft ◽  
Significant Difference

Reconstruction of C2 after tumor destruction and resection remains a significant challenge. Most constructs utilize a strutgraft with plate or screw fixation. A novel C2 prosthesis combining a titanium mesh cage with bilateral C1 shelves and a T-plate has been used successfully in 18 patients. Supplemental posterior instrumentation includes C0-C3 or C1-C3. Biomechanical comparisons of this C2 prosthesis with traditional fixation options have not been reported. Five fresh-frozen human cadaveric cervical spines (C0-C5) were tested intact. Next, the C2 prosthesis, and strut graft and anterior plate constructs were tested with occiput-C3 and C1-C3 posterior fixation. Pure moment loads (up to 1.5 N-m) were applied in flexion and extension, lateral bending, and axial rotation. C1-C3 motion was evaluated using 3 camera motion analysis. Statistical significance was evaluated using one-way repeated measures ANOVA with Student-Newman-Keuls post hoc pairwise comparisons. All constructs provided a statistically significant decrease in motion in this C2 corpectomy model as compared to the intact condition. There was no significant difference in C1-C3 motion between the 4 constructs, regardless of whether the occiput was included in the fixation. Under these loading conditions, both the C2 prostheisis and strut-graft-plate constructs provided initial C1-C3 stability beyond that of the intact specimen. The occiput does not need to be included in the posterior instrumentation.

Time-of-Day Mediates the Influences of Extended Wake and Sleep Restriction on Simulated Driving

2012 ◽  
Vol 29 (5) ◽  
pp. 572-579 ◽  
Author(s):  
Raymond W. Matthews ◽  
Sally A. Ferguson ◽  
Xuan Zhou ◽  
Charli Sargent ◽  
David Darwent ◽  
...  
Keyword(s):  
Time Of Day ◽  
Sleep Restriction ◽  
Simulated Driving

scholarly journals Psychosocial Telephone Counseling for Survivors of Cervical Cancer: Results of a Randomized Biobehavioral Trial

2015 ◽  
Vol 33 (10) ◽  
pp. 1171-1179 ◽  
Author(s):  
Lari Wenzel ◽  
Kathryn Osann ◽  
Susie Hsieh ◽  
Jo A. Tucker ◽  
Bradley J. Monk ◽  
...  
Keyword(s):  
Cervical Cancer ◽  
Repeated Measures ◽  
Statistical Significance ◽  
Multivariable Analysis ◽  
Telephone Counseling ◽  
Longitudinal Change ◽  
Categorical Variables ◽  
Patient Reported ◽  
Cytokine Levels ◽  
Cancer Experience

Purpose Survivors of cervical cancer experience quality-of-life (QOL) disruptions that persist years after treatment. This study examines the effect of a psychosocial telephone counseling (PTC) intervention on QOL domains and associations with biomarkers. Patients and Methods We conducted a randomized clinical trial in survivors of cervical cancer, who were ≥ 9 and less than 30 months from diagnosis (n = 204), to compare PTC to usual care (UC). PTC included five weekly sessions and a 1-month booster. Patient-reported outcomes (PROs) and biospecimens were collected at baseline and 4 and 9 months after enrollment. Changes in PROs over time and associations with longitudinal change in cytokines as categorical variables were analyzed using multivariable analysis of variance for repeated measures. Results Participant mean age was 43 years; 40% of women were Hispanic, and 51% were non-Hispanic white. Adjusting for age and baseline scores, participants receiving PTC had significantly improved depression and improved gynecologic and cancer-specific concerns at 4 months compared with UC participants (all P < .05); significant differences in gynecologic and cancer-specific concerns (P < .05) were sustained at 9 months. Longitudinal change in overall QOL and anxiety did not reach statistical significance. Participants with decreasing interleukin (IL) -4, IL-5, IL-10, and IL-13 had significantly greater improvement in QOL than those with increasing cytokine levels. Conclusion This trial confirms that PTC benefits mood and QOL cancer-specific and gynecologic concerns for a multiethnic underserved population of survivors of cancer. The improvement in PROs with decreases in T-helper type 2 and counter-regulatory cytokines supports a potential biobehavioral pathway relevant to cancer survivorship.

scholarly journals Auriculotherapy to reduce anxiety and pain in nursing professionals: a randomized clinical trial

2017 ◽  
Vol 25 (0) ◽  
Author(s):  
Leonice Fumiko Sato Kurebayashi ◽  
Ruth Natalia Teresa Turrini ◽  
Talita Pavarini Borges de Souza ◽  
Carolina Felicio Marques ◽  
Renata Tavares Franco Rodrigues ◽  
...  
Keyword(s):  
Quality Of Life ◽  
Clinical Trial ◽  
Randomized Clinical Trial ◽  
Nursing Staff ◽  
Repeated Measures ◽  
Statistical Significance ◽  
Cohen’S D ◽  
Pain Visual Analog Scale ◽  
Cohen's D

RESUMEN Objectives: to evaluate the effectiveness of the auricular protocol (APPA) in reducing pain and anxiety and improving the quality of life of the nursing staff of a hospital. Method: randomized clinical trial with an initial sample of 180 professionals divided into 4 groups Control (G1), Seed (G2), Needle (G3) and Tape (G4). The evaluation instruments were the State-Trait Anxiety Inventory, Pain Visual Analog Scale and Quality of Life instrument, applied at the start and after five and 10 sessions (five weeks). Descriptive statistics, analysis of variance (ANOVA) and Cohen's d Index were used in the analysis. Results: there was a statistical difference (p < 0.05) for anxiety according to the repeated measures ANOVA, with better results for the G3 in the final assessment (Cohen's d index 1.08/17% reduction). There was a reduction of pain of 36% in G3 and 24% in G2 and a 13% increase in the mental aspect of quality of life for the G3, although without statistical significance. Conclusion: the APPA protocol reduced the anxiety levels of nursing staff after 10 sessions. Further studies are, however, suggested with new populations and in different contexts so that the results can be confirmed. RBR-5pc43m.

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