Despite improvements in training load and fatigue monitoring, fatigue status may adversely affect intrinsic risk factors, particularly in young footballers. This study aimed to better individualise the fatigue effects of a 75-min football training session in young elite male players. Eighteen players (15.
View Article and Find Full Text PDFThis study aimed to investigate the effect of maturity status on force-velocity relationships in a ballistic lower limb (BLL) test in high-level soccer adolescents and young adults. The population was 61 adolescents (13.0-17.
View Article and Find Full Text PDFThermogenesis is well understood, but the relationships between cold water immersion (CWI), the post-CWI rewarming and the associated physiological changes are not. This study investigated muscle and systemic oxygenation, cardiorespiratory and hemodynamic responses, and gastrointestinal temperature during and after CWI. 21 healthy men completed randomly 2 protocols.
View Article and Find Full Text PDFInt J Sports Physiol Perform
July 2021
Objectives: To identify relevant physiological, mechanical, and strength indices to improve the evaluation of elite mountain bike riders competing in the current Cross-Country Olympic (XCO) format.
Methods: Considering the evolution of the XCO race format over the last decade, the present testing protocol adopted a battery of complementary laboratory cycling tests: a maximal aerobic consumption, a force-velocity test, and a multi-short-sprint test. A group of 33 elite-level XCO riders completed the entire testing protocol and at least 5 international competitions.
Based on a previous study that demonstrated the beneficial effects of sonification on cycling performance, this study investigated which kinematic and muscular activities were changed to pedal effectively. An online error-based sonification strategy was developed, such that, when negative torque was applied to the pedal, a squeak sound was produced in real-time in the corresponding headphone. Participants completed four 6-min cycling trials with resistance values associated with their first ventilatory threshold.
View Article and Find Full Text PDFTo evaluate the physiological requirements imposed by the current mountain biking Cross-Country Olympic (XCO) format. Sixteen Cross-Country cyclists competing at national or international level participated in this study. All participants completed a simulated and a real official race on a cycling-accredited race track.
View Article and Find Full Text PDFTo discover new molecules with an inhibitory activity of melanogenesis a hundred of scorpions, snakes, spiders and amphibians venoms were screened for their capacity to inhibit mushroom tyrosinase using 3,4-l-dihydroxyphenylalanine (l-DOPA) as substrate. The Argiope lobata spider venom proved to be the most active. HPLC fraction containing Argiotoxine-636 (ArgTX-636), a polyamine known for its numerous biological activities, was found to also show a good regulation activity of melanogenesis by inhibiting DOPA and 5,6-dihydroxyindole-2-carboxylic acid (DHICA) oxidases activities, wore by tyrosinase (TYR) and tyrosinase-related protein 1 (TRP-1), respectively.
View Article and Find Full Text PDFScorpion envenoming represents a public health issue in subtropical regions of the world. Treatment and prevention need to promote antitoxin immunity. Preserving antigenic presentation while removing toxin effect remains a major challenge in toxin vaccine development.
View Article and Find Full Text PDFIntermolecular radical 1,2-addition (IRA) of N-tert-butyl-N-(1-diethylphosphono-2,2-dimethylpropyl)aminoxyl (SG1) based alkoxyamines onto activated olefins is used as a tool for peptide ligation. This strategy relies on simple peptide pre-derivatization to obtain (i) a SG1 nitroxide functionalized resin peptide at its N-terminus (SG1-peptide alkoxyamine), (ii) a vinyl functionalized peptide (either at its C-terminus or N-terminus), and does not require any coupling agents.
View Article and Find Full Text PDFPurpose: To study the role of the adrenomedullin system [adrenomedullin and its receptors (AMR), CLR, RAMP2, and RAMP3] in prostate cancer androgen-independent growth.
Experimental Design: Androgen-dependent and -independent prostate cancer models were used to investigate the role and mechanisms of adrenomedullin in prostate cancer hormone-independent growth and tumor-associated angiogenesis and lymphangiogenesis.
Results: Adrenomedullin and AMR were immunohistochemically localized in the carcinomatous epithelial compartment of prostate cancer specimens of high grade (Gleason score >7), suggesting a role of the adrenomedullin system in prostate cancer growth.
Glycopolymer-corona-based micelles are obtained in a one-pot procedure, through reaction of D-mannosamine or D-glucosamine with the N-succinimidyl (NS) esters of a poly(D,L-lactide)-block-poly(N-acryloxysuccinimide-co-N-vinylpyrrolidone) (PLA-b-P(NAS-co-NVP)) amphiphilic copolymer (presenting quasi-alternating NAS/NVP units) in dimethyl sulfoxide (DMSO), followed by nanoprecipitation and dialysis against water. The glycopolymer micelles exhibit a higher CMC and size than those obtained from unmodified copolymer, due to increased hydrophilicity of the external block as a result of sugar derivatization, and the availability of the sugars at the micelle surface is evidenced through interactions with Concanavalin A (Con A) lectin, as attested by turbidimetric measurements and enzyme-linked lectin assay (ELLA). Interestingly, the glycopolymer micelles can be further used for hydrophobic molecule encapsulation and release, as shown with imiquimod, while keeping their interactions with con A intact.
View Article and Find Full Text PDFElectrochemical energy storage is one of the main societal challenges of this century. The performances of classical lithium-ion technology based on liquid electrolytes have made great advances in the past two decades, but the intrinsic instability of liquid electrolytes results in safety issues. Solid polymer electrolytes would be a perfect solution to those safety issues, miniaturization and enhancement of energy density.
View Article and Find Full Text PDFThe first reported combination of regioselective hydro-defluorination and a ligand exchange reaction during the syntheses of neutral iridium(III) complexes is presented. Surprisingly, loss of one fluorine atom per ligand combined with a complete ligand exchange reaction on the transition metal were jointly observed during a bridge-splitting and substitution reaction of two different dimeric iridium(III) precursor complexes with two different ancillary ligands. The regioselectivity of defluorination was evidenced in both cases.
View Article and Find Full Text PDFEfficient biomolecule conjugation to the surface of biodegradable colloidal carriers is crucial for their targeting efficiency in drug/vaccine delivery applications. We here propose a potent strategy to drastically improve peptide immobilization on biodegradable polylactide (PLA) nanoparticles (NPs). Our approach particularly relies on the use of an amphiphilic block copolymer PLA-b-poly(N-acryloxysuccinimide-co-N-vinylpyrrolidone) (PLA-b-P(NAS-co-NVP)) as NP surface modifier, whose the N-succinimidyl (NS) ester functions of the NAS units along the polymer chain ensure N-terminal amine peptide coupling.
View Article and Find Full Text PDFA series of styrene-substituted 1,3,4-oxadiazoles has been designed and investigated as new low-molecular-weight organogelators. The photophysical properties of the resulting thermoreversible organogels have been characterized by UV/Vis absorption and luminescence spectroscopies. Surprisingly, the gelation ability of the oxadiazoles depended on the presence of the styrene moiety as gelation of the investigated oxadiazoles did not take place in its absence.
View Article and Find Full Text PDFWhen pressure is applied to dynamic interactive membranes consisting of micelles composed of a triblock copolymer, their morphologies can be fine-tuned. Membranes with a range of porosities are accessible which can regulate and thereby control filtration performance and also display effective autonomous healing.
View Article and Find Full Text PDFTwo iridium(III) soft salts based on ion-paired dinuclear cationic and mononuclear anionic complexes were designed and investigated as phosphorescent emitters for solution processed OLEDs. New dinuclear cationic complexes were prepared with two different bridging ligands, a carbazole and a phenylene spacer. Best devices were designed with the soft salt bearing a carbazole moiety.
View Article and Find Full Text PDFThe properties of poly(D,L-lactide)-block-poly(2-hydroxyethyl acrylate) (PLA-b-PHEA) block copolymers by means of in vitro / in vivo (rat) degradation are investigated and compared to those of PLA homopolymer. Over 12 weeks, we observe mass loss and molecular weight decrease. In vitro and in vivo findings are very similar for each polymer tested.
View Article and Find Full Text PDFNew photosensitive alkoxyamines have been designed using molecular orbital calculations to improve the selective CO versus NO cleavage. The targeted light-sensitive alkoxyamine is synthesized in one step and its reactivity under UV has been investigated using both ESR and LFP. The ability of this alkoxyamine to control the photopolymerization of n-butyl acrylate is evidenced through a process called nitroxide-mediated photopolymerization NMP(2) .
View Article and Find Full Text PDFMacromol Rapid Commun
August 2010
The photochemical properties of two new photocleavable alkoxyamines bearing a benzophenone-derived chromophore were studied by electron spin resonance (ESR). The CO bond cleavage has been demonstrated and the photolysis rate constants (k(d) ) determined over a large range of light intensity through the monitoring of the nitroxide concentration in aerated conditions. The obtained kinetic data highlight for the first time the linear dependence of k(d) on the light intensity for alkoxyamines: this should be a driving factor for nitroxide mediated radical photopolymerization (NMP(2) ).
View Article and Find Full Text PDFThe search for photosensitive alkoxyamines represents a huge challenge. The key parameters governing the cleavage process remain unknown. The dissociation process of light sensitive alkoxyamines is studied as a function of their chemical structures.
View Article and Find Full Text PDFPurpose: Our goal was to evaluate the five-year follow-up results of the Scorpio single radius total knee arthroplasty.
Method: We performed a retrospective study based upon a multicentre database to evaluate the minimum five-year follow-up clinical and radiological results of 747 patients (831 knees) who underwent primary Scorpio single radius total knee arthroplasty.
Results: The mean age of the patients was 71.
AaCtx is the first chlorotoxin-like peptide isolated from Androctonus australis scorpion venom. Its amino acid sequence shares 70% similarity with chlorotoxin from Leiurus quinquestriatus scorpion venom, from which it differs by twelve amino acids. Due to its very low concentration in venom (0.
View Article and Find Full Text PDFDue to the academic and industrial interest of Nitroxide Mediated Polymerization (NMP), a lot of investigations have focused on the kinetics of this process. During the last decade, although the simplified kinetic scheme--equilibrium reactions between dormant species (alkoxyamine) and active species (alkyl radicals and nitroxides), propagation reaction of the macro-alkyl radical, and termination reactions--was suitable to predict the main trends at the macromolecular level, it has become obvious that it was not sufficient to describe all the kinetic effects involved in the NMP process. Indeed, like the conventional radical polymerization, NMP should be described as a 3 stage process including initiation, propagation, and self- and cross-termination.
View Article and Find Full Text PDFBlock copolymers constitute a fascinating class of polymeric materials that are used in a broad range of applications. The performance of these materials is highly coupled to the physical and chemical properties of the constituting block copolymers. Traditionally, the composition of block copolymers is obtained by 1H NMR spectroscopy on purified copolymer fractions.
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