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The metabolic power and energetic demands of elite Gaelic football match play.
No full textBACKGROUND: Metabolic power has not yet been investigated within elite Gaelic football. The aim of the current investigation was to compare the metabolic power demands between positional groups and examine the temporal profile of elite Gaelic football match play. METHODS: Global positional satellite system (GPS) data were collected from 50 elite Gaelic football players from 4 inter-county teams during 35 elite competitive matches over a three season period. A total of 351 complete match samples were obtained for final analysis. Players were categorised based on positional groups; full-back, half-back, midfield, half- forward and full-forward. Instantaneous raw velocity data was obtained from the GPS and exported to a customised spreadsheet which provided estimations of both speed based, derived metabolic power and energy expenditure variables (total distance, high speed distance, average metabolic power, high power distance and total energy expenditure). RESULTS: Match mean distance was 9222 ± 1588 m, reflective of an average metabolic power of 9.5-12.5 W∙kg-1, with an average energy expenditure of 58-70 Kj∙kg-1 depending on position. There were significant differences between positional groups for both speed-based and metabolic power indices. Midfielders covered more total and high-speed distance, as well as greater average and overall energy expenditure compared to other positions (p < 0.001). A reduction in total, high-speed, and high-power distance, as well as average metabolic power throughout the match (p < 0.001) was observed. CONCLUSIONS: Positional differences exist for both metabolic power and traditional running based variables. The middle three positions (midfield, half-back and half-forward) possess greater activity profiles when compared to other positional groups. The reduction in metabolic power and traditional running based variables are comparable across match play. The current study demonstrates that metabolic power may contribute to our understanding of Gaelic football match-play
Disturbance accumulation hampers fish assemblage recovery long after the worst mining spill in the Iberian Peninsula
No full textThe influence of environmental variables on native and exotic fish species richness and diversity was analysed 8 years after one of the most environmentally harmful toxic spills worldwide. Environment-diversity relationships were addressed on different scales, and values were also compared with those of six similar basins not affected by the spill, with the aim of determining whether this disturbance was still exerting an influence on the fish assemblage. Results showed higher native species richness in environments with low human influence, no reservoirs upstream, a large drainage area and coarse substrate reaches. For native fish, variables at both the catchment and site were equally relevant. Exotic fish were mainly favoured by site-scale factors such as valley width downstream from the reservoir, where the alteration of the river channel and accumulated disturbances give them an advantage vs native species. Overall, 8 years after the accident, richness and diversity of the Guadiamar fish assemblage seemed more affected by anthropogenic impacts than by the long-term influence of the toxic spill. This work highlights that the potentially synergic effects of anthropogenic factors must be taken into account when monitoring the long-term effects of pollution events
Age- and Activity-Related Differences in the Abundance of Myosin Essential and Regulatory Light Chains in Human Muscle
No full textTraditional methods for phenotyping skeletal muscle (e.g., immunohistochemistry) are labor-intensive and ill-suited to multixplex analysis, i.e., assays must be performed in a series. Addressing these concerns represents a largely unmet research need but more comprehensive parallel analysis of myofibrillar proteins could advance knowledge regarding age- and activity-dependent changes in human muscle. We report a label-free, semi-automated and time efficient LC-MS proteomic workflow for phenotyping the myofibrillar proteome. Application of this workflow in old and young as well as trained and untrained human skeletal muscle yielded several novel observations that were subsequently verified by multiple reaction monitoring (MRM). We report novel data demonstrating that human ageing is associated with lesser myosin light chain 1 content and greater myosin light chain 3 content, consistent with an age-related reduction in type II muscle fibers. We also disambiguate conflicting data regarding myosin regulatory light chain, revealing that age-related changes in this protein more closely reflect physical activity status than ageing per se. This finding reinforces the need to control for physical activity levels when investigating the natural process of ageing. Taken together, our data confirm and extend knowledge regarding age- and activity-related phenotypes. In addition, the MRM transitions described here provide a methodological platform that can be fine-tuned to suite multiple research needs and thus advance myofibrillar phenotyping
Metabolism of the new psychoactive substances N,N-diallyltryptamine (DALT) and 5-methoxy-DALT and their detectability in urine by GC-MS, LC-MS (n) , and LC-HR-MS-MS
No full textN,N-Diallyltryptamine (DALT) and 5-methoxy-DALT (5-MeO-DALT) are synthetic tryptamine derivatives commonly referred to as so-called new psychoactive substances (NPS). They have psychoactive effects that may be similar to those of other tryptamine derivatives. The objectives of this work were to study the metabolic fate and detectability, in urine, of DALT and 5-MeO-DALT. For metabolism studies, rat urine obtained after high-dose administration was prepared by precipitation and analyzed by liquid chromatography–high-resolution mass spectrometry (LC–HR–MS–MS). On the basis of the metabolites identified, several aromatic and aliphatic hydroxylations, N-dealkylation, N-oxidation, and combinations thereof are proposed as the main metabolic pathways for both compounds. O-Demethylation of 5-MeO-DALT was also observed, in addition to extensive glucuronidation or sulfation of both compounds after phase I transformation. The cytochrome P450 (CYP) isoenzymes predominantly involved in DALT metabolism were CYP2C19, CYP2D6, and CYP3A4; those mainly involved in 5-MeO-DALT metabolism were CYP1A2, CYP2C19, CYP2D6, and CYP3A4. For detectability studies, rat urine was screened by GC–MS, LC–MS n , and LC–HR–MS–MS after administration of low doses. LC–MS n and LC–HR–MS–MS were deemed suitable for monitoring consumption of both compounds. The most abundant targets were a ring hydroxy metabolite of DALT, the N,O-bis-dealkyl metabolite of 5-MeO-DALT, and their glucuronides. GC–MS enabled screening of DALT by use of its main metabolites only
Studies on the metabolism and toxicological detection of the new psychoactive designer drug 2-(4-iodo-2,5-dimethoxyphenyl)-N-[(2-methoxyphenyl)methyl]ethanamine (25I-NBOMe) in human and rat urine using GC-MS, LC-MSn, and LC-HR-MS/MS
No full text25I-NBOMe, a new psychoactive substance, is a potent 5-HT2A receptor agonist with strong hallucinogenic potential. Recently, it was involved in several fatal and non-fatal intoxication cases. The aim of the present work was to study its phase I and II metabolism and its detectability in urine screening approaches. After application of 25I-NBOMe to male Wistar rats, urine was collected over 24 h. The phase I and II metabolites were identified by LC-HR-MS/MS in urine after suitable workup. For the detectability studies, standard urine screening approaches (SUSA) by GC-MS, LC-MSn, and LC-HR-MS/MS were applied to rat and also to authentic human urine samples submitted for toxicological analysis. Finally, an initial CYP activity screening was performed to identify CYP isoenzymes involved in the major metabolic steps. 25I-NBOMe was mainly metabolized by O-demethylation, O,O-bis-demethylation, hydroxylation, and combinations of these reactions as well as by glucuronidation and sulfation of the main phase I metabolites. All in all, 68 metabolites could be identified. Intake of 25I-NBOMe was detectable mainly via its metabolites by both LC-MS approaches, but not by the GC-MS SUSA. Initial CYP activity screening revealed the involvement of CYP1A2 and CYP3A4 in hydroxylation and CYP2C9 and CYP2C19 in O-demethylation. The presented study demonstrated that 25I-NBOMe was extensively metabolized and could be detected only by the LC-MS screening approaches. Since CYP2C9 and CYP3A4 are involved in initial metabolic steps, drug–drug interactions might occur in certain constellations
Transcriptome analysis of response to drought in poplar interspecific hybrids.
No full textTo investigate the response of poplar hybrids to drought, leaves were collected from plants to which water was suspended for 8 and 13 days. After measuring the respective relative water content, RNAs were isolated from leaves of moderately and severely droughted plants and from control plants, and Illumina RNA sequencing was performed to analyze RNA synthesis in these tissues. Our data provide a resource (available at Gene Expression Omnibus database under GSE64044) to be employed for comparative analyses of drought response in different poplar species, with the long-term aim of developing strategies to improve plant productivity under drought
Dissolution Enhancement and Formulation of Rapid-Release Lornoxicam Mini-Tablets
No full textThe aim was to enhance the dissolution of lornoxicam (LOR) and to produce mini-tablets with an optimised system to provide a rapid-release multi-particulate formulation. LOR systems were prepared through co-evaporation with either polyethylene glycol 6000 or Pluronic® F-68 (PLU) and adsorption onto Neusilin® US2 alone or co-adsorption in the presence of different amounts of polysorbate 80. All systems were characterised by FT-IR, differential scanning calorimetry, X-ray diffraction, flowability and dissolution techniques. Mini-tablets were prepared using the system with the optimum dissolution profile and flowability. Tensile strengths, content uniformity and dissolution profiles of the mini-tablets were evaluated. The effects of different excipients and storage conditions on mini-tablet properties were also studied. The optimised rapid-release LOR mini-tablets were further evaluated for their in vivo pharmacokinetic profile. The co-evaporate of LOR with PLU showed significantly faster dissolution and superior flowability and was evaluated together with three directly compressible excipients (Cellactose® 80, StarLac® (STA) and Emcompress®) for mini-tablet formulation. The formulation with STA provided the optimum results in terms of tensile strength content uniformity and rapid drug release following a 3-month stability study and was selected for further in vivo evaluation. The pharmacokinetic profile indicated the potential of the mini-tablets achieving rapid release and increased absorption of LO
Write, draw, show, and tell: a child-centred dual methodology to explore perceptions of out-of-school physical activity
No full textBackground
Research to increase children’s physical activity and inform intervention design has, to date, largely underrepresented children’s voices. Further, research has been limited to singular qualitative methods that overlook children’s varied linguistic ability and interaction preference. The aim of this study was to use a novel combination of qualitative techniques to explore children’s current views, experiences and perceptions of out-of-school physical activity as well as offering formative opinion about future intervention design.
Methods
Write, draw, show and tell (WDST) groups were conducted with 35 children aged 10–11 years from 7 primary schools. Data were analysed through a deductive and inductive process, firstly using the Youth Physical Activity Promotion Model as a thematic framework, and then inductively to enable emergent themes to be further explored. Pen profiles were constructed representing key emergent themes.
Results
The WDST combination of qualitative techniques generated complimentary interconnected data which both confirmed and uncovered new insights into factors relevant to children’s out-of-school physical activity. Physical activity was most frequently associated with organised sports. Fun, enjoyment, competence, and physical activity provision were all important predictors of children’s out-of-school physical activity. Paradoxically, parents served as both significant enablers (i.e. encouragement) and barriers (i.e. restricting participation) to physical activity participation. Some of these key findings would have otherwise remained hidden when compared to more traditional singular methods based approaches.
Conclusions
Parents are in a unique position to promote health promoting behaviours serving as role models, physical activity gatekeepers and choice architects. Given the strong socialising effect parents have on children’s physical activity, family-based physical activity intervention may offer a promising alternative compared to traditional school-based approaches. Parents' qualitative input is important to supplement children’s voices and inform future family-based intervention design. The WDST method developed here is an inclusive, interactive and child-centred methodology which facilitates the exploration of a wide range of topics and enhances data credibility
The Influence of Mirror-Visual Feedback on Training-Induced Motor Performance Gains in the Untrained Hand
No full textThe well-documented observation of bilateral performance gains following unilateral motor training, a phenomenon known as cross-limb transfer, has important implications for rehabilitation. It has recently been shown that provision of a mirror image of the active hand during unilateral motor training has the capacity to enhance the efficacy of this phenomenon when compared to training without augmented visual feedback (i.e., watching the passive hand), possibly via action observation effects [1]. The current experiment was designed to confirm whether mirror-visual feedback (MVF) during motor training can indeed elicit greater performance gains in the untrained hand compared to more standard visual feedback (i.e., watching the active hand). Furthermore, discussing the mechanisms underlying any such MVF-induced behavioural effects, we suggest that action observation and the cross-activation hypothesis may both play important roles in eliciting cross-limb transfer. Eighty participants practiced a fast-as-possible two-ball rotation task with their dominant hand. During training, three different groups were provided with concurrent visual feedback of the active hand, inactive hand or a mirror image of the active hand with a fourth control group receiving no training. Pre- and post-training performance was measured in both hands. MVF did not increase the extent of training-induced performance changes in the untrained hand following unilateral training above and beyond those observed for other types of feedback. The data are consistent with the notion that cross-limb transfer, when combined with MVF, is mediated by cross-activation with action observation playing a less unique role than previously suggested. Further research is needed to replicate the current and previous studies to determine the clinical relevance and potential benefits of MVF for cases that, due to the severity of impairment, rely on unilateral training programmes of the unaffected limb to drive changes in the contralateral affected limb
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