2,997 research outputs found
Left ventricular torsional mechanics and myocardial iron load in beta-thalassaemia major: a potential role of titin degradation
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Dynamic dyssynchrony and impaired contractile reserve of the left ventricle in beta-thalassaemia major: an exercise echocardiographic study
BACKGROUND: Performance of the left ventricle during exercise stress in thalassaemia patients is uncertain. We aimed to explore the phenomenon of dynamic dyssynchrony and assess contractile reserve in patients with beta-thalassaemia major and determine their relationships with myocardial iron load. METHODS AND RESULTS: Thirty-two thalassaemia patients (16 males), aged 26.8+/-6.9 years, without heart failure and 17 healthy controls were studied. Their left ventricular (LV) volumes, ejection fraction, systolic dyssynchrony index (SDI), and myocardial acceleration during isovolumic LV contraction (IVA) were determined at rest and during submaximal bicycle exercise testing using 3-dimensional and tissue Doppler echocardiography. Myocardial iron load as assessed by T2* cardiac magnetic resonance in patients were further related to indices of LV dyssynchrony and contractile reserve. At rest, patients had significantly greater LV SDI (p4.6%, control+2SD) increased from baseline 25% to 84% in patients. Delta SDI(exercise-baseline) correlated with exercise-baseline differences in LV ejection fraction (p<0.001) and stroke volume (p = 0.006). Compared with controls, patients had significantly less exercise-induced increase in LV ejection fraction, cardiac index, and IVA (interaction, all p<0.05) and had impaired contractile reserve as reflected by the gentler IVA-heart rate slope (p = 0.018). Cardiac T2* in patients correlated with baseline LV SDI (r = -0.44, p = 0.011) and IVA-heart rate slope (r = 0.36, p = 0.044). CONCLUSIONS: Resting LV dyssynchrony is associated with myocardial iron load. Exercise stress further unveils LV dynamic dyssynchrony and impaired contractile reserve in patients with beta-thalassaemia major.published_or_final_versio
Measuring achievement emotions questionnaire for physical education (AEQ-PE): a confirmatory study in Malay language
Availability of data and materials:
The dataset used and analysed during the current study is available from the corresponding author on reasonable request.Background: This study aimed to verify a translated Malay version of the Achievement Emotions Questionnaire for Physical Education (AEQ-PE) by assessing the level of achievement emotions in six constructs among the Malaysian primary school pupils using the Confirmatory Factor Analysis (CFA). Methods: A total of 607 Malay pupils, comprising 240 (39.5%) boys and 367 (60.5%) girls aged between 10 and 11, were recruited from 10 schools to answer the questionnaire, which measured their views on 24 items through a five-point Likert scale. The AEQ-PE was translated into Malay language (AEQ-PE-M) using forwarding to backward translation techniques. Certain phrases were adopted in accordance with the local culture and vocabulary appropriate for primary school pupils. CFA was performed using the Mplus 8.0 software, and the final model demonstrated high reliability in terms of the composite reliability and Cronbach’s alpha. Results: Analysis of the CFA showed an acceptable fit indices in CFI (0.936), TLI (0.926), RMSEA = 0.039 (90% CI, 0.034, 0.045) and SRMR (0.049) of the AEQ-PE measurement model. All of the items in the original AEQ-PE version were retained and deemed suitable for Malay primary school pupils. Conclusion: The AEQ-PE-M with 24 items was a suitable tool for measuring the level of school children’s involvement in determining achievement emotions and their motivation towards physical education.This study was supported by Research University’s Individual Grant (1001/PPSK/8012370) from Universiti Sains Malaysia
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Psychometric properties of the malay-language quality of life enjoyment and satisfaction scale: A confirmatory study on malaysian children
Data Availability Statement:
The data is available upon request from the authors.Copyright © 2021 by the authors. The objective of this study was to validate the translated Malay version of the Quality of Life Enjoyment and Satisfaction Questionnaire (Q-LES-Q-M) scale among Malaysian primary school children using the confirmatory factor analysis (CFA). The Q-LES-Q-M measures the level of enjoyment and satisfaction experienced with relation to physical health, feelings, homework, and leisure. The participants were 607 Malay students, 240 (39.5%) boys and 367 (60.5%) girls, with an age range from 10 to 11 years old. The original version of the Q-LES-Q was translated into the Malay language by forward to backward translation procedures with consideration for the local culture and suitable vocabulary for primary school students. The participants then completed the Q-LES-Q-M. CFA was performed using Mplus 8 software. Using CFA, the initial model did not result in a good data fit. Further analysis of the CFA suggested some changes to the model to improve the fit indices. Model modification included the deletion of three problematic items and co-varying some error items. This resulted in improved fit indices and 40 items remained in the final model. The final model showed good reliability based on two indicators of composite reliability (CR) and Cronbach’s alpha (CA). The factors with their CR and CA were physical activity (CR = 0.857, CA = 0.854), feelings (CR = 0.808, CA = 0.813), homework (CR = 0.837, CA = 0.837) and leisure (CR = 0.742, CA = 0.737). The final measurement consists of 40 items. The retained items were deemed suitable for Malay primary school children. The revised Q-LES-Q-M with 40 items is suitable for measuring the levels of children’s involvement in determining the enjoyment and satisfaction of learning and physical activity.The research was partially supported by the Exercise Medicine Research Grant (EMRG/19004)
Intermittent Moderate Energy Restriction Improves Weight Loss Efficiency in Diet-Induced Obese Mice
BACKGROUND:Intermittent severe energy restriction is popular for weight management. To investigate whether intermittent moderate energy restriction may improve this approach by enhancing weight loss efficiency, we conducted a study in mice, where energy intake can be controlled. METHODS:Male C57/Bl6 mice that had been rendered obese by an ad libitum diet high in fat and sugar for 22 weeks were then fed one of two energy-restricted normal chow diets for a 12-week weight loss phase. The continuous diet (CD) provided 82% of the energy intake of age-matched ad libitum chow-fed controls. The intermittent diet (ID) provided cycles of 82% of control intake for 5-6 consecutive days, and ad libitum intake for 1-3 days. Weight loss efficiency during this phase was calculated as (total weight change) ÷ [(total energy intake of mice on CD or ID)-(total average energy intake of controls)]. Subsets of mice then underwent a 3-week weight regain phase involving ad libitum re-feeding. RESULTS:Mice on the ID showed transient hyperphagia relative to controls during each 1-3-day ad libitum feeding period, and overall ate significantly more than CD mice (91.1±1.0 versus 82.2±0.5% of control intake respectively, n = 10, P<0.05). There were no significant differences between CD and ID groups at the end of the weight loss or weight regain phases with respect to body weight, fat mass, circulating glucose or insulin concentrations, or the insulin resistance index. Weight loss efficiency was significantly greater with ID than with CD (0.042±0.007 versus 0.018±0.001 g/kJ, n = 10, P<0.01). Mice on the CD exhibited significantly greater hypothalamic mRNA expression of proopiomelanocortin (POMC) relative to ID and control mice, with no differences in neuropeptide Y or agouti-related peptide mRNA expression between energy-restricted groups. CONCLUSION:Intermittent moderate energy restriction may offer an advantage over continuous moderate energy restriction, because it induces significantly greater weight loss relative to energy deficit in mice
Cross-Cultural Adaptation and Validation of the Malay Version of Sports Motivation Scale-II
The 18-item Sport Motivation Scale (SMS-II) is one of the most-utilised scales measuring athletes’ motivation and its psychometric properties. However, we found no Malay version used to examine the Malaysian multi-ethnic population. Thus, the study aimed to translate and validate the SMS-II into the Malay version using confirmatory factor analysis. A total of 436 (16.44 ± 1.22) state athletes were asked to complete the SMS-II Malay version, which utilised the forward–backwards translation method. The results showed an acceptable fit with the data (CFI = 0.906, SRMR = 0.064; RMSEA = 0.056) and internal consistency, with a Cronbach’s alpha value that exceeded 0.50, which supported its usage for the assessment of motivation among the multi-ethnic Malaysian athletes. The Cronbach’s alpha values of all the factors were satisfactory, except for introjected regulation. Thus, further studies are needed to improve the reliability of such factors. Nonetheless, the Malay version of SMS-II was found to be valid and reliable for assessing the level of motivation of the multi-ethnic Malaysian athletes.Research University’s Individual Grant from Universiti Sains Malaysia (USM); Exercise Medicine Research Gran
Identification of the Functional Domain of Thyroid Hormone Receptor Responsible for Polychlorinated Biphenyl–Mediated Suppression of Its Action in Vitro
Diffraction-limited ultrabroadband terahertz spectroscopy
Diffraction is the ultimate limit at which details of objects can be resolved in conventional optical spectroscopy and imaging systems. In the THz spectral range, spectroscopy systems increasingly rely on ultra-broadband radiation (extending over more 5 octaves) making a great challenge to reach resolution limited by diffraction. Here, we propose an original easy-to-implement wavefront manipulation concept to achieve ultrabroadband THz spectroscopy system with diffraction-limited resolution. Applying this concept to a large-area photoconductive emitter, we demonstrate diffraction-limited ultra-broadband spectroscopy system up to 14.5 THz with a dynamic range of 103. The strong focusing of ultrabroadband THz radiation provided by our approach is essential for investigating single micrometer-scale objects such as graphene flakes or living cells, and besides for achieving intense ultra-broadband THz electric fields
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Kawa model on mental health, sports and physical performance: A mini review
Availability of data and materials:
The dataset developed and analysed during the current review is available from the corresponding author on request.Copyright © 2023 The Authors. Successful sports performance is characterized by psychological, physical, technical, and tactical factors. Of these factors, the psychological factor is typically ignored despite contributing more than 50% toward success in sporting performance. This review aimed to introduce the Kawa model as a new methodology to promote sports and physical performance through developing mental health ability. The Kawa model is developed by occupational therapists and used to promote mental health ability in individuals by enabling self-awareness of their difficulties and exploring possible solutions. It consists of the following five elements: water, river banks, rocks, driftwood, and space. This research would further explore the usage of the Kawa model in addressing various psychological issues and how these improvements can enhance sports and physical performance. The literature search was performed by using Google Scholar, PubMed, Web of Science and Scopus as a database with specific keywords. In conclusion, this research provides an overview of the potential for the use of the Kawa model in promoting mental health ability included self-awareness, self-understanding, goal-setting, self-efficacy, stress and anxiety control for sports and physical performance and lays the foundation for future research in this area.Ministry of Higher Education Malaysia for Fundamental Research Grant Scheme (FRGS) with Project Code: FRGS/1/2020/SKK06/USM/03/13
Inhibition of Y1 receptor signaling improves islet transplant outcome
Failure to secrete sufficient quantities of insulin is a pathological feature of type-1 and type-2 diabetes, and also reduces the success of islet cell transplantation. Here we demonstrate that Y1 receptor signaling inhibits insulin release in β-cells, and show that this can be pharmacologically exploited to boost insulin secretion. Transplanting islets with Y1 receptor deficiency accelerates the normalization of hyperglycemia in chemically induced diabetic recipient mice, which can also be achieved by short-term pharmacological blockade of Y1 receptors in transplanted mouse and human islets. Furthermore, treatment of non-obese diabetic mice with a Y1 receptor antagonist delays the onset of diabetes. Mechanistically, Y1 receptor signaling inhibits the production of cAMP in islets, which via CREB mediated pathways results in the down-regulation of several key enzymes in glycolysis and ATP production. Thus, manipulating Y1 receptor signaling in β-cells offers a unique therapeutic opportunity for correcting insulin deficiency as it occurs in the pathological state of type-1 diabetes as well as during islet transplantation.Islet transplantation is considered one of the potential treatments for T1DM but limited islet survival and their impaired function pose limitations to this approach. Here Loh et al. show that the Y1 receptor is expressed in β- cells and inhibition of its signalling, both genetic and pharmacological, improves mouse and human islet function.info:eu-repo/semantics/publishe
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