431. Effect of ionizing radiation on human skeletal muscle precursor cellsMihaela Jurdana, Maja Čemažar, Katarina Pegan, Tomaž Marš, 2013, published scientific conference contribution Abstract: Background. Long term effects of different doses of ionizing radiation on human skeletal muscle myoblast proliferation, cytokine signalling and stress response capacity were studied in primary cell cultures.Materials and methods. Human skeletal muscle myoblasts obtained from muscle biopsies were cultured and irradiated with a Darpac 2000 X-ray unit at doses of 4, 6 and 8 Gy. Acute effects of radiation were studied by interleukin - 6 (IL-6) release and stress response detected by the heat shock protein (HSP) level, while long term effects were followed by proliferation capacity and cell death.Results. Compared with non-irradiated control and cells treated with inhibitor of cell proliferation Ara C, myoblast proliferation decreased 72 h post-irradiation, this effect was more pronounced with increasing doses. Post-irradiation myoblast survival determined by measurement of released LDH enzyme activity revealed increased activity after exposure to irradiation. The acute response of myoblasts to lower doses of irradiation (4 and 6 Gy) was decreased secretion of constitutive IL-6. Higher doses of irradiation triggered a stress response in myoblasts, determined by increased levels of stress markers (HSPs 27 and 70).Conclusions. Our results show that myoblasts are sensitive to irradiation in terms of their proliferation capacity and capacity to secret IL-6. Since myoblast proliferation and differentiation are a key stage in muscle regeneration, this effect of irradiation needs to be taken in account, particularly in certain clinical conditions.
Keywords: myoblasts, irradiation, proliferation, interleukin 6, muscle regeneration, apoptosis
Published in RUP: 30.12.2015; Views: 4044; Downloads: 150
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432. Športna dejavnost, učni uspeh in samopodoba štirinajstletnih učencev in učenkMaja Meško, Mateja Videmšek, Tasja Videmšek, Jože Štihec, Damir Karpljuk, Jera Gregorc, 2013, original scientific article Abstract: Namen raziskave je bil ugotoviti, ali obstajajo razlike v učni uspešnosti in samopodobi učencev 9. razredov OŠ glede na to, kako pogosto se ti ukvarjajo s športom. Zanimalo nas je, ali imajo učenci, ki se več ukvarjajo s športom, boljšo samopodobo in boljši učni uspeh ter ali imajo učenci z boljšim učnim uspehom boljšo samopodobo. V ta namen smo anketirali 168 učencev 9. razredov osnovnih šol. Podatke smo obdelali s statističnim programom SPSS; za ugotavljanje razlik med skupinami smo uporabili analizo variance. Rezultati raziskave so pokazali, da imajo športno bolj dejavni učenci boljši učni uspeh ter nekoliko boljšo samopodobo. Učenci, ki se več ukvarjajo s športom, v bistveno večji meri menijo, da jih imajo sošolci radi, da se v svoji koži dobro počutijo, da so všeč nasprotnemu spolu in da lahko v poklicu veliko dosežejo. Prav tako smo ugotovili, da imajo učenci z boljšim učnim uspehom nekoliko boljšo samopodobo; menijo, da jih imajo sošolci radi, da so pametni in da v poklicu lahko veliko dosežejo. Glede na dobljene rezultate predvidevamo, da ukvarjanje z ustreznimi športnimi dejavnostmi pripomore k boljšemu učnemu uspehu ter razvoju pozitivne samopodobe pri mladostnikih. Prav zato je potrebno otroke in mladostnike nenehno spodbujati in jim omogočati, da so redno športno dejavni, saj s tem krepijo samopodobo in samospoštovanje ter pozitivno vplivajo tudi na svoj učni uspeh.
Keywords: učni uspeh, športna dejavnost, samopodoba, osnovne šole, vprašalnik
Published in RUP: 30.12.2015; Views: 4278; Downloads: 79
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