Seasonal changes in selected physical and physiological variables in male handball players

© 2018 Ljubomir Pavlović et al., published by Sciendo 2018. Literature search shows that there is a shortage of studies that have investigated the relationships between the physical conditioning markers monitored over the course of a season and the quantitative assessments of training and competition in elite handball players. Thus, the aim of our work was to follow changes in speed, strength, power and endurance of elite male handball players during an entire season. The study was performed within a group of 14 elite male senior handball players who were tested four times during season (T1, T2, T3, T4). The testing consisted of the following procedures: 1) measuring anthropometric characteristics (body height, body weight, body fat, % of fatty tissue), 2) measuring motorical (physical) capabilities (maximal muscle force and power, speed, explosive strength), 3) measuring physiological characteristics (anaerobic capacity, cardiorespiratory endurance). Explosive strength decreased at the end of season compared to the first part of season (T1 vs T4: p = 0.00, T2 vs T4: p = 0.00), as well as the total work done on modified Wingate test (T1 vs T4: p = 0.01). In contrast, blood lactate levels after the third (T1 vs T2: p = 0.00, T1 vs T3: p = 0.02; T1 vs T4:p = 0.00) and fourth (T1 vs T3: p = 0.02) stage of endurance test were the highest at the beginning of the season. Our results suggest that anaerobic capabilities of players were the ones mostly affected by long season and inadequate training program, while on the other side, aerobic capabilities improved by the end of season. Explanation for such results may be found in insufficient strength training or interference of endurance training with strength development

Supplementary data for the article: Mrđan, G. S.; Vastag, G. G.; Škorić, D. Đ.; Radanović, M. M.; Verbić, T. Ž.; Milčić, M. K.; Stojiljković, I. N.; Marković, O. S.; Matijević, B. M. Synthesis, Physicochemical Characterization, and TD–DFT Calculations of Monothiocarbohydrazone Derivatives. Structural Chemistry 2021, 32 (3), 1231–1245. https://doi.org/10.1007/s11224-020-01700-y.

Supplementary material for: [https://doi.org/10.1007/s11224-020-01700-y]Related to published version: [https://cherry.chem.bg.ac.rs/handle/123456789/4453

Supplementary material for the article: Rančić, M. P.; Stojiljković, I.; Milošević, M.; Prlainović, N.; Jovanović, M.; Milčić, M. K.; Marinković, A. D. Solvent and Substituent Effect on Intramolecular Charge Transfer in 5-Arylidene-3-Substituted-2,4-Thiazolidinediones: Experimental and Theoretical Study, 2016. https://doi.org/10.1016/j.arabjc.2016.12.013

Supplementary material for: [https://doi.org/10.1016/j.arabjc.2016.12.013]Related to published version: [http://cherry.chem.bg.ac.rs/handle/123456789/305

Changes in the muscular outputs of young judoists during resistance exercises performed on unstable equipment: A case study

Background and Study Aim: Resistance exercises under unstable conditions have gained popularity among athletes. The aim of the study was to investigate the changes in muscular outputs (peak power and velocity of movement) during bench presses and squats under unstable conditions in comparison to the outputs under stable conditions. Material/Methods: A total of 20 participants, divided into two groups, took part in the study The first group consisted of 9 top-level young male judoists, while the second group consisted of 11 students. All of the exercises were performed once 70% of one-repetition maximum (1RM) was determined. Results: The analysis showed a significant reduction in muscular outputs during squats under unstable conditions (the BOSU ball) in comparison to stable conditions for the group of judoists. However, there was no significant reduction in muscular outputs during the bench presses under unstable conditions (the Swiss ball) compared to the stable flat bench. For the group of students, the analysis showed a significant reduction in muscular outputs during the bench press under unstable conditions when compared to the stable flat bench. In addition, for this group the muscular outputs were significantly lower during squats under unstable in comparison to stable conditions. Conclusions: The bench press as a resistance exercise performed on a Swiss ball with reduced training load cannot be recommended as an effective training model for judoists. Nevertheless, the squat with reduced training load under unstable conditions provided sufficient challenges to the neuromuscular system and could be incorporated into training programs. © ARCHIVES OF BUDO|SCIENCE OF MARTIAL ARTS

Ontogenetic profile of ecto-5 '-nucleotidase in rat brain synaptic plasma membranes

Ecto-5'-nucleotidase (CD73; EC 3.1.3.5, e-5NT) is regarded as the key enzyme in the extracellular formation of adenosine, which acts as a neuromodulator and important trophic and homeostatic factor in the brain. In the present study, we have investigated e-5NT activity, kinetic properties concerning AMP hydrolysis and the enzyme protein abundance in the purified synaptic plasma membrane (SPM) preparations isolated from whole female rat brain at different ages. We observed pronounced increase in AMP hydrolyzing activity in SPM during maturation, with greatest increment between juvenile (15-day-old) and pre-pubertal (30-day-old) rats. Immunodetection of e-5NT protein in the SPM displayed the reverse pattern of expression, with the maximum relative abundance at juvenile and minimum relative abundance in the adult stage. Negative correlation between the enzyme activity and the enzyme protein abundance in the SPM indicates that e-5NT has additional roles in the synaptic compartment during postnatal brain development, other than those related to AMP hydrolysis. Determination of kinetic parameters, K(m) and V(max), suggested that the increase in the enzyme activity with maturation was entirely due to the increase in the enzyme catalytic efficiency (V(max)/K(m)). Finally, double immunofluorescence staining against e-5NT and presynaptic membrane marker syntaxin provided first direct evidence for the existence of this ecto-enzyme in the presynaptic compartment. The results of the study suggest that e-5NT may be a part of general scheme of brain development and synapse maturation and provide rationale for the previously reported inconsistencies between enzyme immunohistochemical and biochemical studies concerning localization of e-5NT in the brain. (C) 2011 ISDN. Published by Elsevier Ltd. All rights reserved.Serbian Ministry of Science and Technology [173044, 41014

Ontogenetic profile of ecto-5 '-nucleotidase in rat brain synaptic plasma membranes

Ecto-5'-nucleotidase (CD73; EC 3.1.3.5, e-5NT) is regarded as the key enzyme in the extracellular formation of adenosine, which acts as a neuromodulator and important trophic and homeostatic factor in the brain. In the present study, we have investigated e-5NT activity, kinetic properties concerning AMP hydrolysis and the enzyme protein abundance in the purified synaptic plasma membrane (SPM) preparations isolated from whole female rat brain at different ages. We observed pronounced increase in AMP hydrolyzing activity in SPM during maturation, with greatest increment between juvenile (15-day-old) and pre-pubertal (30-day-old) rats. Immunodetection of e-5NT protein in the SPM displayed the reverse pattern of expression, with the maximum relative abundance at juvenile and minimum relative abundance in the adult stage. Negative correlation between the enzyme activity and the enzyme protein abundance in the SPM indicates that e-5NT has additional roles in the synaptic compartment during postnatal brain development, other than those related to AMP hydrolysis. Determination of kinetic parameters, K(m) and V(max), suggested that the increase in the enzyme activity with maturation was entirely due to the increase in the enzyme catalytic efficiency (V(max)/K(m)). Finally, double immunofluorescence staining against e-5NT and presynaptic membrane marker syntaxin provided first direct evidence for the existence of this ecto-enzyme in the presynaptic compartment. The results of the study suggest that e-5NT may be a part of general scheme of brain development and synapse maturation and provide rationale for the previously reported inconsistencies between enzyme immunohistochemical and biochemical studies concerning localization of e-5NT in the brain. (C) 2011 ISDN. Published by Elsevier Ltd. All rights reserved.Serbian Ministry of Science and Technology [173044, 41014

Ecto-5 '-nucleotidase (e-5NT) switches from neurons to astrocytes after cortical stab injury in rat

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Ecto-5 '-nucleotidase (e-5NT) switches from neurons to astrocytes after cortical stab injury in rat

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Biochemical characterization of soluble nucleotide pyrophosphatase/phosphodiesterase activity in rat serum

Biochemical properties of nucleotide pyrophosphatase/phosphodiesterase (NPP) in rat serum have been described by assessing its nucleotide phosphodiesterase activity, using p-nitrophenyl-5'-thymidine monophosphate (p-Nph-5'-TMP) as a substrate. It was demonstrated that NPP activity shares some typical characteristics described for other soluble NPP, such as divalent cation dependence, strong alkaline pH optimum (pH 10.5), inhibition by glycosaminoglycans, and K (m) for p-Nph-5'-TMP hydrolysis of 61.8 +/- A 5.2 mu M. In order to characterize the relation between phosphodiesterase and pyrophosphatase activities of NPP, we have analyzed the effects of different natural nucleotides and nucleotide analogs. ATP, ADP, and AMP competitively inhibited p-Nph-5'-TMP hydrolysis with K (i) values ranging 13-43 mu M. Nucleotide analogs, alpha,beta-metATP, BzATP, 2-MeSATP, and dialATP behaved as competitive inhibitors, whereas alpha,beta-metADP induced mixed inhibition, with K (i) ranging from 2 to 20 mu M. Chromatographic analysis revealed that alpha,beta-metATP, BzATP, and 2-MeSATP were catalytically degraded in the serum, whereas dialATP and alpha,beta-metADP resisted hydrolysis, implying that the former act as substrates and the latter as true competitive inhibitors of serum NPP activity. Since NPP activity is involved in generation, breakdown, and recycling of extracellular adenine nucleotides in the vascular compartment, the results suggest that both hydrolyzable and non-hydrolyzable nucleotide analogs could alter the amplitude and direction of ATP actions and could have potential therapeutic application.Serbian Ministry of Science and Technology [E143005

Pannexin-1 Upregulation in Cultured Astrocytes Is Induced By Scratch Wound

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