Inflammatory Blood Biomarker Kynurenine Is Linked With Elevated Neuroinflammation and Neurodegeneration in Older Adults: Evidence From Two 1H-MRS Post-Processing Analysis Methods.

Rationale and Objectives: Pro-inflammatory processes have been argued to play a role in conditions associated with cognitive decline and neurodegeneration, like aging and obesity. Only a limited number of studies have tried to measure both peripheral and central biomarkers of inflammation and examined their interrelationship. The primary aim of this study was to examine the hypothesis that chronic peripheral inflammation would be associated with neurometabolic changes that indicate neuroinflammation (the combined elevation of myoinositol and choline), brain gray matter volume decrease, and lower cognitive functioning in older adults. Materials and Methods: Seventy-four older adults underwent bio-impedance body composition analysis, cognitive testing with the Montreal Cognitive Assessment (MoCA), blood serum analysis of inflammatory markers interleukin-6 (IL-6) and kynurenine, magnetic resonance imaging (MRI), and proton magnetic resonance spectroscopy (1H-MRS) of the brain. Neurometabolic findings from both Tarquin and LCModel 1H-MRS post-processing software packages were compared. The regions of interest for MRI and 1H-MRS measurements were dorsal posterior cingulate cortex (DPCC), left hippocampal cortex (HPC), left medial temporal cortex (MTC), left primary sensorimotor cortex (SM1), and right dorsolateral prefrontal cortex (DLPFC). Results: Elevated serum kynurenine levels were associated with signs of neuroinflammation, specifically in the DPCC, left SM1 and right DLPFC, and signs of neurodegeneration, specifically in the left HPC, left MTC and left SM1, after adjusting for age, sex and fat percentage (fat%). Elevated serum IL-6 levels were associated with increased Glx levels in left HPC, left MTC, and right DLPFC, after processing the 1H-MRS data with Tarquin. Overall, the agreement between Tarquin and LCModel results was moderate-to-strong for tNAA, tCho, mIns, and tCr, but weak to very weak for Glx. Peripheral inflammatory markers (IL-6 and kynurenine) were not associated with older age, higher fat%, decreased brain gray matter volume loss or decreased cognitive functioning within a cohort of older adults. Conclusion: Our results suggest that serum kynurenine may be used as a peripheral inflammatory marker that is associated with neuroinflammation and neurodegeneration, although not linked to cognition. Future studies should consider longitudinal analysis to assess the causal inferences between chronic peripheral and neuroinflammation, brain structural and neurometabolic changes, and cognitive decline in aging.

Effect of acute game-based exercises on steroid hormones and cognitive performance in adolescents.

PURPOSE: While exercise was found to affect cognitive performance in adolescents, the underlying mechanisms need to be considered. This study compared the effect of a 20 min game-based exercise with different intensities on hormonal responses and potential links to cognitive performance. METHODS: 37 adolescents (24 girls and 13 boys; 15-16 years of age) were randomly assigned into light intensity (LIG; 58.64% HRmax), vigorous intensity (VIG; 89.51% HRmax), and control group (CON). The concentration of salivary Testosterone and Cortisol was measured before, immediately after, 20 min and 60 min after the intervention. RESULTS: Repeated-measure ANOVA revealed that neither light nor vigorous game-based exercise acutely affects Testosterone, while Cortisol was higher in the VIG, 20 min after the intervention compared to the LIG and CON. Furthermore, changes in Testosterone were negatively associated with changes in cognitive performance after the acute vigorous intensity exercise (r = -0.63, p = .039) and control condition (r = -0.78, p = .003), but positively associated with post-intervention cognitive performance after the acute light intensity exercise (r = 0.67, p = .012). CONCLUSION: The intensity of game-based exercise affected Cortisol concentration in adolescents, while Testosterone concentration did not change after the intervention. On the other hand, exercise intensity plays an important role in the association between Testosterone concentration and cognitive performance.

Effects of Different Types of Exercise Training on Fine Motor Skills and Testosterone Concentration in Adolescents: A Cluster Randomized Controlled Trial.

We sought to compare the effect of two types of exercise training on fine motor skills and to establish their association with the salivary testosterone. Research participants, 135 adolescents (68 adolescent females; mean age = 12.76, SD = 0.85) were assigned into three groups: coordinative exercise (CE), cardiovascular exercise (CVE), and the control group (CON). Fine motor skills were assessed with a drawing trail test and salivary testosterone concentration was measured before and after 10 weeks of intervention. There were no significant changes in fine motor skills and testosterone concentration after either CE or CVE training. However, a significant positive correlation between post-test fine motor skills and post-test testosterone concentration was found after the CVE training. One type of exercise training cannot be singled out as more effective for fine motor skills and testosterone activity. Nevertheless, our results showed a relationship between fine motor skills and testosterone concentration after the CVE training. Thus, the type of exercise training is important in the exercise-induced testosterone effect on fine motor skills.

The beneficial effects of acute strength training on sway activity and sway regularity in healthy older men: Evidence from a posturography study.

The effects of acute strength training on balance control were studied in healthy older human men (age-range 60-77y). Participants performed the Tandem Romberg Stance while completing an attention demanding cognitive task (Mathematical Counting) before and after a single acute strength training session applied to the lower limb musculature (experimental group; n = 19) or no intervention (control group; n = 18). Balance stability and the automaticity of balance control were estimated through the calculation of the center-of-pressure (CoP) velocity (Vcop) and the statistical regularity (wavelet entropy) of the CoP trajectory (WEcop), respectively. Training included 3 sets of 3 repetitions of barbell squats using Smith Machine, ranging from 90 % of one repetition maximum (1RM) to 100 % 1RM with 3 min rest between repetitions and 5 min rest between sets. Vcop and WEcop decreased after training (all time main effects, p ≤ 0.028) but group time interactions were not significant (all, p ≥ 0.056). Exploratory analyses revealed that participants in the experimental group showed a significant decrease of Vcop and WEcop in the mediolateral (ML) directions from pre to post [ML Vcop: 15.4 %; Bonferroni-corrected p = 0.048); ML WEcop: 10.5 %; Bonferroni-corrected p = 0.016]. A trend towards a decrease in Vcop and WEcop was also observed in controls, with more prominent gains in the anteroposterior than in the ML direction (Bonferroni-corrected p > 0.2). Overall, findings suggest that acute strength training may improve attentional control of balance along the narrow dimension of the support. Further studies are warranted to examine the specific mechanisms underlying these findings.

A randomized controlled trial on the influence of two types of exercise training vs control on visuospatial processing and mathematical skills: The role of cortisol.

While physical exercise training (PET) is undoubtedly very important for children and adolescents, there is still a lack of research dealing with the specific impact of different types of PET on cognitive and academic performance and the activity of the hypothalamic-pituitary-adrenal (HPA) axis. The purpose of this study was to compare the impact of two different types of exercise training on visuospatial processing and mathematical skills in adolescents with the analysis of cortisol. We randomly assigned 135 adolescents (12-15 years of age) into three groups: coordinative exercise (CE), cardiovascular exercise (CVE), and control (CON) group. Computerized cognitive test (matching grids), mathematical skills and salivary cortisol level were evaluated before and after 10 weeks of PET (three times per week for 45 min) after school. Reaction time of the matching grids task decreased in all groups while the accuracy was better in CE comparing to control. In addition, the CE group improved the mathematical skills. The participants who improved visuospatial performance had higher mathematics scores after the intervention. However, we did't find any effect of the exercise training intervention on salivary cortisol nor on the link between cortisol and visuospatial processing. Future research should analyze the moderators that influence this link.

Early anterior knee pain in male adolescent basketball players is related to body height and abnormal knee morphology.

OBJECTIVES: To compare knee torque, range of motion, quality of movement, and morphology in dominant and nondominant legs of male adolescent basketball players with and without anterior knee pain and untrained peers. DESIGN: Cross-sectional. SETTING: Sports performance laboratory. PARTICIPANTS: Male basketball players aged 14-15 years with and without anterior knee pain and healthy untrained subjects (n = 88). MAIN OUTCOME MEASURES: Basketball players were allocated to a symptomatic or asymptomatic group based on self-reported anterior knee pain. Associations between pain and body mass, height, passive range of motion, muscle peak torque, coactivation, neuromuscular control, proprioception, and ultrasound observations were investigated. RESULTS: The prevalence of pain did not differ significantly between sides. Of 176 knees inspected, 44 were painful, and 26 of these exhibited abnormalities in ultrasonography. Symptomatic players were 5.0 and 6.9 cm taller than asymptomatic players and controls, respectively (P < 0.05). In athletes with knee pain, the odds ratios of morphological abnormalities and greater height were increased by 8.6 and 5.0 times (P < 0.001). CONCLUSION: Knee pain prevalence in adolescent basketball players was not related to differences between sides but was higher in tall players. Knee pain was accompanied by morphological abnormalities detected with ultrasound.

Sway regularity and sway activity in older adults' upright stance are differentially affected by dual task.

Age-related changes in postural control are attributed to visual, vestibular and proprioceptive dysfunctions, muscle weakness, and reduced availability of neural resources required for efficient balance control. Concurrent performance of complex cognitive tasks while standing or walking is expected to increase balance instability due to under-recruitment of brain resources and insufficient allocation of attention to the postural task. Both balance instability and attentional control of movements can, nonetheless, be determined from the center of pressure (CoP) measurements by examining the effects of dual-task on the amount of sway activity (as measured by CoP velocity - Vcop) and the statistical regularity of the CoP trajectory (the wavelet entropy of the signal - WEcop). The abovementioned characteristics were examined in the present study in a group of 13 healthy older adults. The task involved maintaining Romberg stance for 25 s with or without performing an attention demanding cognitive tasks (word memorization or mathematical counting). A linear mixed-model study was designed to analyze the extent to which sway activity can predict sway regularity. Findings from the present study showed that, on average, Vcop and WEcop were positively correlated (p = 0.014), suggesting that older individuals who exhibited greater amounts of sway (i.e., higher Vcop) also increased sway irregularity of the posturogram - as evidenced by a higher level of wavelet entropy of the CoP trajectory. Nevertheless, results of the linear mixed model showed that significant positive associations between Vcop and WEcop were found only in dual task (R ≥ 0.67, p ≤ 0.012). Furthermore, dual-task effects (% change in performance) on both sway characteristics were not significant (p > 0.1), suggesting that none of the attention demanding cognitive tasks used in the present study was sufficient to divert a critical amount of attentional resources from the postural task. Finally, performance of the mathematical counting (but not the word memorization) task was deteriorated from sitting to standing, however this effect was marginal (p = 0.075). Taken together, we proposed that while dual task could hinder balance control, postural stability may still be maintained by allocating more attentional resources to the postural task and reducing automatized control.

Comparison of the effects of whole-body cooling during fatiguing exercise in males and females.

The effects of cold stress on exercise performance and fatigue have been thoroughly investigated only in males, and thus the general understanding of these effects relates only to males. The aim of this study was to determine whether whole-body cooling has different effects on performance during fatiguing exercise in males and females. Thirty-two subjects (18 males and 14 females) were exposed to acute cold stress by intermittent immersion in 14°C water until their rectal temperature reached 35.5°C or for a maximum of 170 min. Thermal responses and motor performance were monitored before and after whole-body cooling. Whole-body cooling decreased rectal, muscle and mean skin temperatures in all subjects (p<0.05), and these changes did not differ between males and females. Cold stress decreased the fatigue index (FI) of a sustained 2-min maximal voluntary contraction (MVC) only in males (p<0.05). There were no sex differences in central and peripheral fatigability, or muscle electromyographic activity. This observed sex difference (i.e., body cooling-induced decrease in the FI of a sustained MVC in males but not in females) supports the view of sex effects on performance during fatiguing exercise after whole-body cooling.

Test-Retest Cross-Reliability of Tests to Assess Neuromuscular Function as a Multidimensional Concept.

The purpose of this investigation was to estimate the test-retest cross-reliability of peripheral and central changes with respect to nonlinear and linear measures of a surface electromyography (EMG) signal measured during isometric maximal voluntary contraction (MVC) combined with superimposed electrical stimulation during a brief and fatiguing task involving the ankle plantar flexors over 2 follicular phases of menstrual cycle. Ten healthy female adults underwent 1 familiarization session and 5 identical test-retest sessions. The results showed that the decrease in plantar flexor EMG components (root mean square [RMS], mean frequency [MnF], wavelet packet entropy [WPE]) for soleus and gastrocnemius muscles, central activation ratio (CAR) and MVC, and contractile properties (P20, P100, PTT-100, and half-relaxation time) of the plantar flexor muscles at the end of 2-minute MVC were similar (time effect; p < 0.001, η(p)² > 0.7, statistical power [SP] > 99%) and exhibited high stability over 5 trials (trial effect; p > 0.05; η(p)² < 0.2, SP < 30%). High reliability between trials was found for 5-second MVC (intraclass correlation coefficient [ICC] > 0.82, p < 0.001) and meaningful reliability for 2-minute MVC (ICC > 0.66, p < 0.01). In conclusion, in young healthy women, measurements of neuromuscular function, such as RMS, MnF, and WPE of a surface EMG signal, MVC, and CAR from a brief and sustained MVC of the ankle plantar flexors, are reliable, and multidimensional stability was found with respect to both high and low correlation outcomes across the 5 identical test-retest trials of any 2 properties measured during brief and sustained MVC.

The effect of temperature on amount and structure of motor variability during 2-minute maximum voluntary contraction.

INTRODUCTION: In this study, we questioned whether local cooling of muscle or heating involving core and muscle temperatures are the main indicators for force variability. METHODS: Ten volunteers performed a 2-min maximum voluntary contraction (MVC) of the knee extensors under control (CON) conditions after passive heating (HT) and cooling (CL) of the lower body. RESULTS: HT increased muscle and rectal temperatures, whereas CL lowered muscle temperature but did not affect rectal temperature. During 2-min MVC, peak force decreased to a lower level in HT compared with CON and CL experiments. Greater central fatigue was found in the HT experiment, and there was less in the CL experiment than in the CON experiment. CONCLUSIONS: Increased core and muscle temperature increased physiological tremor and the amount and structural complexity of force variability of the exercising muscles, whereas local muscle cooling decreased all force variability variables measured.

Reliability and validity of DPA-1 testing after anterior cruciate ligament reconstruction.

There is a lack of equipment and methods for the reliable and valid measurements of human neuromuscular control. To overcome this limitation, an analyzer of dynamic parameters (DPA-1) of human hand and leg movements was constructed by Kaunas University of Technology and "Katra" engineers in collaboration with the Lithuanian Academy of Physical Education. The aim of the study was to determine the reliability and validity of the tests performed on the DPA-1 in healthy and injured subjects after the anterior cruciate ligament (ACL) reconstruction surgery. MATERIAL AND METHODS. The men who had undergone a unilateral ACL reconstruction (n=17, on the average 3.8 months [SD, 2.1] after the surgery) and healthy untrained men (n=17) performed the research protocol twice within 24 hours in between. Average reaction time, mean and maximal movement speed, time to reach maximal speed, and movement distance of the right and left feet for the patients and of the dominant foot for the healthy subjects using the DPA-1 as well as the scores of isokinetic muscle strength and self-assessment tests were registered. RESULTS. There was a significantly reduced concentric peak torque on the injured knee compared with the uninjured knee during knee extension, and the mean score of the Lysholm scale for the injured knee was 69.1 (SD, 13.7) (P<0.05, compared between legs). The test-retest reliability for all the DPA-1 tests varied from 0.68 to 0.94 (P<0.05). However, there were no significant differences in most variables measured by the DPA-1 between injured knee, uninjured knee, and control knee. CONCLUSIONS. The results revealed low validity of the DPA-1 tests for the evaluation of patients following ACL surgery, despite the reliability of these tests varied from moderate to very high.

[Lithuanian version of the Nursing Outcomes Classification Use Survey: development and psychometric evaluation]. / Slaugos rezultatu klasifikacijos lietuviskos anketos parengimas ir psichometrinis ivertinimas.

UNLABELLED: Cross-cultural tests and research instruments are broadly used to adapt questionnaires developed in different countries and cultures. The Nursing Outcomes Classification (NOC)--a comprehensive, standardized classification of patient outcomes--can be used to evaluate the results of nursing interventions. OBJECTIVE: To develop and test psychometrically the Lithuanian version of the Nursing Outcomes Classification Use Survey. MATERIAL AND METHODS: A Lithuanian version of the Nursing Outcomes Classification Use Survey was developed following traditional methodological procedures of research instrument translation and adaptation. The newly developed instrument was tested with a sample of 70 staff nurses from nursing and supportive care hospitals. The content and practical feasibility of the Lithuanian version of NOC was measured for its reliability and validity. Psychometric analysis was conducted with the statistical package SPSS 13.0 for Windows. Results revealed a successful translation of NOC from English to Lithuanian with validity and acceptability of a shortened Lithuanian version (244 items instead of the original 330 items). Satisfactory internal consistency (Cronbach alpha >0.80 in 18 classes and in 6 classes out of 28 Cronbach alpha between 0.70 and 0.80) was defined, and stability in time was very good with a 7-day break between repeated translations (Spearman-Brown coefficient for the whole instrument was 0.806, ranging from 0.707 to 0.970). The majority of items in the Lithuanian version correlated with measurement class (correlation coefficients >0.40). CONCLUSIONS: The Lithuanian version of Nursing Outcomes Classification Use Survey is a reliable, valid, and applicable to outcome identification in clinical practice and nursing research. Future research and further evaluation of the newly developed Lithuanian version of NOC is suggested.