Protective effects of therapeutic cold and heat against the oxidative damage induced by a muscle strain injury in rats

Abstract

The mechanisms of action of physical agents commonly used to treat skeletal muscle lesions are not well understood. In this study, we examined whether the modulation of oxidative stress is involved in the beneficial effects of cold and heat on gastrocnemius muscle strain injury. Adult male Wistar rats were submitted to a strain injury and treated with therapeutic agents in an isolated or combined form. Strain damage caused an increase in muscle and blood oxidative damage. We suggest that this oxidative damage might be related to the impairment of the muscle cell structure, since we observed a significant positive correlation between increased plasma creatine kinase activity and both oxidized dichlorofluoresceine and lipid peroxidation levels in muscle and blood. The intensity of the inflammatory response appears also to be an important factor in the genesis of oxidative damage immediately following a muscle strain injury. Therapeutic cold seems to be more effective in preventing the damage induced by a strain injury, possibly due to its capacity to control the impairment of muscle cell structure and to modulate the intensity of the inflammatory response that follows a muscle strain injury.     

Maternal warmth and prosocial behaviors among low-SES adolescents: Considering interactions between empathy and moral conviction

ABSTRACT

The study examined the links among maternal warmth and adolescents’ empathic concern, moral conviction and prosocial behaviors. Participants were 311 adolescents from a low-income community (M age = 16.10 years; range = 14–19 years; 58.7% girls; 82.7% white; 13.6% Latinx). The results demonstrated that maternal warmth was positively associated with adolescents’ empathic concern and moral conviction. Empathic concern was positively associated with three common forms of prosocial behaviors, and moral conviction was positively associated with four types of prosocial behaviors. Empathic concern and moral conviction also interacted to predict selfishly and selflessly motivated prosocial behaviors. Discussion will focus on the role of maternal warmth in fostering sociomoral tendencies.     

Greater basal skeletal muscle AMPKα phosphorylation in men than in women: Associations with anaerobic performance

Objectives: This study was designed to investigate the association of gender, fibre type composition, and anaerobic performance with the basal skeletal muscle signalling cascades regulating muscle phenotype. Design: Muscle biopsies were obtained from 25 men and 10 women all young and healthy. Methods. Protein phosphorylation of Thr¹⁷²AMPKα, Ser²²¹ACCβ, Thr²⁸⁶CaMKII as well as total protein abundance of PGC-1α, SIRT1, and CnA were measured by Western blot and anaerobic performance by the Wingate test. Results: Percent type I myosin heavy chain (MHC I) was lower in men (37.1?±?10.4 vs. 58.5?±?12.5, P?P?P?221ACCβ and Thr²⁸⁶CaMKII fractional phosphorylation tended to be higher in men (P?=?.1). PGC1-α and SIRT1 total protein expression was similar in men and women, whereas CnA tended to be higher in men (P?=?.1). Basal AMPKα phosphorylation was linearly related to the percentage of MHC I in men (r?=?0.56; P?Conclusion: In summary, skeletal muscle basal AMPKα phosphorylation is higher in men compared to women, with no apparent effect on anaerobic performance.     

Acute modification in plasma lipid levels in ultramarathon runners

We aimed to evaluate the effects of a 24-h ultramarathon, an aerobic test of high physical load, on lipid profile and apolipoproteins B (ApoB) and A1 (ApoA1) levels, minimally modified low-density lipoprotein (LDL), and oxidised LDL. Prospective evaluation of 16 male athletes who participated in an ultramarathon run, where the objective was to run the greatest distance possible in 24 h. Fourteen participants completed the run. The mean distance achieved was 133.1 km (maximum of 169.6 km). There was a trend in reduction of triglycerides and total cholesterol (P = 0.06 and 0.05, respectively), without significant modifications in high-density lipoprotein, LDL and ApoA1 levels (P = 0.16; 0.55 and 0.67). There was a marked reduction in ApoB levels (P < 0.001), correlated directly to the distance covered (Pearson R = 0.68). Accordingly, an increase in the LDL/ApoB ratio was observed. The stress of this physical activity was not associated to an increase in minimally modified LDL or oxidised LDL. Lipid profile levels were not acutely altered by prolonged physical activity. Similarly, there was no evidence of greater oxidation of LDL over a 24-h period of physical activity. The reduction in ApoB was directly proportional to the distance covered, suggesting an acute positive change in phenotype of LDL molecules.     

Intervention in fluency problems in pupils with Specific Language Impairment (SLI) / Intervención en problemas de fluidez en alumnado con Trastorno Específico del Lenguaje (TEL)

The aim of this research has been to prove the efficacy of an intervention programme on the problems of phonetic and semantic fluency and mazes in narrative discourse in children with Specific Language Impairment (SLI). The sample consisted of 34 children diagnosed with SLI and 34 children with normal language development. For the selection of the sample, the Clinical Evaluation of Language Fundamentals (CELF-3), Peabody Picture Vocabulary Test, Hearing Association and the Visual Association subtests of the Illinois Test of Psycholinguistic Abilities (ITPA), and the Kaufman Brief Intelligence Test (KBIT) were used. Performance in phonemes (F, A & S), semantic fluency (animals) and the appearance of mazes or repairs in a narrative task were also evaluated. The intervention programme consisted of 72 sessions of 15 minutes each, using phonetic and semantic fluency activities with phonetic and semantic clues. Differences between groups were statistically significant in repetitions and false connectors.     

Effect of the level of effort during resistance training on intraocular pressure

Background: We aimed to evaluate the influence of the level of effort during four basic resistance exercises leading to muscular failure on intraocular pressure (IOP) and ocular perfusion (OPP), as well as the role of exercise type and sex. Methods: Twenty-five young adults (12 women) performed 10 repetitions against their 10-RM (repetition maximum) load in the squat, military press, biceps curl and calf raise exercises. IOP was measured before, during and after exercise, whereas OPP was indirectly assessed before and after each exercise. Results: There was a progressive IOP rise during exercise (p?η²?=?0.531), which was dependent on exercise type (p?=?0.020, η²?=?0.125). The squat exercise induced higher IOP increments in comparison to the other exercises (corrected p-values?p-values?=?0.012 and 0.002). OPP exhibited a significant reduction when leading to muscular failure (p?=?0.001, η²?=?0.364), being statistically significant for the squat and military press exercises (corrected p-values?=?0.037 and 0.047). No effect of sex was found for IOP and OPP (p?>?0.05). Conclusions: A single set of resistance training leading to muscular failure causes an instantaneous and progressive IOP rise in healthy young individuals. These IOP rises depend on exercise type (squat?>?military press?=?biceps curl?>?calf raise), but not on participant´s sex. OPP diminished as a consequence of performing resistance training exercise, being statistically significant for the squat and military press exercises. Future studies should include glaucoma patients aiming to corroborate the generalizability of our findings.     

Analysis of the distance covered by Brazilian professional futsal players during official matches

The purpose of this study was to measure and characterise the distances covered by Brazilian professional futsal players. The trajectories of 93 players during five matches were obtained using an automatic tracking method. The distances covered were analysed for different game conditions: over the entire game and during the times when the ball was out of play and in play separately. When the entire game was considered, the results showed that there was a reduction in the total distance covered per minute from the first [median ± IQR (interquartile range): 97.9 ± 16.2 m/min] to the second half (median = 90.3 m/min; IQR = 12.0), and when only the in-play time was considered (first half: 136.6 ± 17.2 m/min; second half: 129.2 ± 16.7 m/min). The percentage of distance covered in the standing and walking velocity range was higher in the second half than in the first when considering the entire game (30.8% and 28.0%, respectively) and during the in-play time (19.3% and 16.2%, respectively). In conclusion, this study verified that futsal players reduced the physical performance during the second half.     

The Relations of Maternal Practices and Characteristics to Children''s Vicarious Emotional Responsiveness

This study examined the relations of maternal vicarious emotional responding and child-rearing practices, as well as familial emotional environment, to 5-6 and 8-9-year-old children's vicarious emotional responding. There were some correspondences between mothers' and children's heart rate, facial, and self-reported reactions to a sympathy-inducing film. Maternal sympathy/perspective taking and reinforcement of sympathy/prosocial behavior, as well as negative subordinate emotion in the home, were associated with markers of girls' sympathy; mothers' personal distress (for girls), restrictiveness regarding displays of hurtful negative emotions (particularly for young girls), and negative dominant emotion in the home (for both sexes) were associated with markers of personal distress. Mothers' linking of the film character's experience to children's own experience was associated with children's responsiveness to the film, and mother's verbalizations during the film concerning her own emotional state and role taking were associated with boys' self-reported sympathy.     

Yo-Yo Intermittent Endurance Test-Level 1 to monitor changes in aerobic fitness in pre-pubertal boys

The present study aimed to examine the performance and heart rate responses during the Yo-Yo Intermittent Endurance Test-Level 1 (Yo-Yo IE1) in children under the age of 10. One hundred and seven male children (7–9 years) performed the Yo-Yo IE1 at the beginning (M₁), middle (M₂) and end (M₃) of the school year. Data from individual heart rate curves of the Yo-Yo IE1 were analysed in order to detect the inflection point between an initial phase of fast rise in heart rate values and a second phase in which the rise of the heart rate values is much smaller. The distance covered in the Yo-Yo IE1 improved from M₁ to M₃ (884 ± 496 vs. 1032 ± 596 m; p < 0.05; d = 0.27), with intermediate values for M₂ (962 ± 528 m). Peak heart rate (HR_peak) decreased from M₁ to M₂ and M₃ (204 ± 9, 202 ± 9 and 200 ± 9 bpm, respectively; p < 0.05; d = 0.25–0.42). The 7th shuttle of the test (280 m), corresponding to 2.5 min, was identified as the inflection point between the two phases. Also, absolute heart rate at the 7th shuttle decreased progressively throughout the year (185 ± 9, 183 ± 10, and 179 ± 10 bpm; p < 0.05; d = 0.31–0.61). The present study provides evidence of the usefulness of a maximal as well as a submaximal version of Yo-Yo IE1 as a tool to monitor changes in aerobic fitness in pre-pubertal children.     

Examining the influence of international large-scale assessments on national education policies

This paper examines whether, to what extent, and how international large-scale assessments (ILSAs) have influenced education policy-making at the national level. Based on an exploratory review of the research and policy literature on ILSAs and two surveys administered to educational policy experts, researchers, policymakers, and educators, our research found that ILSAs, with their multiple and ambiguous uses, increasingly function as solutions in search for the right problem – that is, they appear to be used as tools to legitimize educational reforms. The survey results pointed to a growing perception among stakeholders that ILSAs are having an effect on national educational policies, with 38% of respondents stating that ILSAs were generally misused in national policy contexts. However, while the ILSA literature indicates that these assessments are having some influence, there is little evidence that any positive or negative causal relationship exists between ILSA participation and the implementation of education reforms. Perhaps the most significant change associated with the use of ILSAs in the literature reviewed is the way in which new conditions for educational comparison have been made possible at the national, regional, and global levels.