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Öğe The effects of different skill training on neuromuscular electric activity of the limbs in amateur sportsmen(Ios Press, 2005) Kaygusuz, A; Meric, F; Ertem, K; Duzova, H; Karakoc, Y; Ozcan, CIn this study, we investigated the effects of different skills of sport on electromyography (EMG) of limb muscles in sportsmen. Two different skill groups of sport consisted of 10 soccer players who use extensively lower limb, and 10 handball, basketball and volleyball players with selectively high usage of the upper limb. Surface EMG (sEMG) were recorded from the abductor pollicis brevis and gastrocnemius muscles of subjects. In addition, Hoffmann reflex (H-reflex) were recorded from the lower limb of participants. EMG findings of two groups were compared with each other and age-sex matched sedentary controls. Amplitude and area of sEMG recorded from gastrocnemius muscle of handball -basketball-volleyball players were significantly higher than those of soccer players (p < 0.01 and p < 0.05), whereas not significantly different based on the abductor pollicis brevis (p > 0.05 in both). F-response of both muscles and H-reflex of handball-basketball-volleyball players were also significantly higher from those of soccer players and control group (p < 0.05 for all), whereas only F-response of gastrocnemius muscle of soccer player was significantly lower than that of control group (p < 0.05). We conclude that EMG amplitude of gastrocnemius muscle, F-response and H-reflex times of lower limbs increase in handball-basketball-volleyball players due to the nature of training skills. Volleyball, handball or basketball training contributes to neuromuscular differences in both upper and lower extremities more than football training because both extremities are extensively used in these sport categories.Öğe Effects of nucleoside analogues on liver regeneration 70% partially hepatectomized rats(Elsevier Science Inc, 2006) Yilmaz, S; Kirimlioglu, V; Kirimlioglu, H; Coban, S; Kayaalp, C; Yilmaz, M; Karakoc, YThe alternatives for prophlaxis and treatment of recurrent hepatitis B virus infection have increased since new oral nucleoside analogues have become available. We conducted this experimental study to investigate the effect in the liver of these agents on the expression of transforming growth factor alpha (TGF-alpha) and on proliferation index, estimated by Ki-67. Thirty male Wistar albino rats were randomized into three groups: group A (n = 10) received adefovir dipivoxil (40 mg/kg/d per gavage); group B (n = 10), lamivudine (L; 30 mg/kg/d per gavage); and group C (n = 10) did not receive any treatment and were the control group. Groups A and B were treated for 3 days. Animal treatment began on day -1. After performing 70% partial hepatectomy on day 0, all rats were sacrificed on postoperative day 2 to harvest liver tissues for histopathological examination. We stained and indexed Ki-67 and TGF-alpha immunohistochemically on the hepatectomy surface and in the parenchyma, Ki-67 and TGF-a indices were significantly higher in group A compared with group B (P = .001 and P = .004, respectively, and P = .003 and P = .001, respectively). When the L group was compared with the control group for results on the hepatectomy surface and the parenchyma, Ki-67 and TGF-a indexes were insignificantly different (P = .6 and P = .3, respectively, and P = .1 and P = .6, respectively). Based on the results of this experimental study, we concluded that Adefovir dipivoxil has greater proliferative effect on liver parenchyma and in the cut surface than does lamivudine.Öğe Effects of training period on haemorheological variables in regularly trained footballers(Bmj Publishing Group, 2005) Karakoc, Y; Duzova, H; Polat, A; Emre, MH; Arabaci, IObjective: To investigate the effects of one football training period on haemorheological variables in regularly trained footballers. Method: Ten subjects were randomly selected from the reserve team of a football club in the Turkish Premier League. During the last week of the football season, one day before a standard training session and two days after the previous league match, venous blood samples were taken (pre-exercise). After 90 minutes of standard training, further blood samples were taken (post-exercise). Blood lactate, blood viscosity, plasma fibrinogen, blood clotting time, acid-base variables, and plasma Na+, K+, and Ca2+ were determined. Results: Haemoglobin, packed cell volume, and mean corpuscular volume were all significantly decreased, whereas white blood cells and platelets were both increased after training. Blood viscosity decreased but the reduction was not significant. Blood lactate, plasma glucose, and Na+ content were significantly increased, but standard bicarbonate, actual bicarbonate, and Ca2+ were significantly decreased. Blood clotting time had shortened significantly after training. Blood viscosity was inversely correlated with plasma glucose concentration (r = -0.48 and p = 0.032). Conclusions: The results show that blood viscosity tends to decrease as the result of this type of training. This is due to a reduction in packed cell volume and mean corpuscular volume. The increased blood lactate does not have an adverse effect on the blood of these subjects because protective mechanisms develop with regular training throughout the season.Öğe Experimental stress-induced changes in trace element levels of various tissues in rats(Wiley-Liss, 2003) Karakoc, Y; Yurdakos, E; Gulyasar, T; Mengi, M; Barutcu, UBIn this study, we investigated the effects of acute and chronic immobilization stress on the Zn, Cu, and Fe levels of the temporal lobe, brain stem, spleen, and liver tissues in rats. The animals in the acute stress group were put in the cages, one time only for 120 min. For the chronic stress groups (2h and 4h), the rats were kept in the cages daily for 2 and 4 h, respectively, for 5 consecutive days. Controls and immobilized rats were decapitated, and then tissue samples were taken. Zn, Cu, and Fe levels in the temporal lobe, brain stem, spleen, and liver were measured by flame atomic absorption spectrophotometer. Our results showed that acute immobilization stress causes endogenous Zn and Cu release from the brain tissues. In the 2h chronic stress group, Fe levels markedly increase in the temporal lobe and brain stem whereas they decrease in the spleen and liver. In the 4h chronic stress group, Fe levels increase in the temporal lobe and brain stem while Zn and Cu levels increase in the spleen and liver. In the acute and chronic immobilization stress groups, mobilization of Zn and Cu can be related to the induction of metallothionein (MT) in the liver and spleen but not in the brain. On the other hand, excess Fe in the temporal lobe and brain stem causes us to believe think that the brain iron transport proteins may be involved, and enhanced, by immobilization stress.Öğe Lipid peroxidation and antioxidative enzyme activities in childhood epilepsy(B C Decker Inc, 2002) Turkdogan, D; Toplan, S; Karakoc, YThis study aimed to investigate the relationship among lipid peroxidation, subsequent activation of scavenger enzymes (superoxide dismutase and glutathione peroxidase), and the presence of structural abnormality in 52 epileptic children receiving monotherapy (medically responsive) or polytherapy (medically intractable). Plasma lipid peroxidation in epileptic patients with abnormal magnetic resonance imaging (MRI) findings significantly increased as compared with that of 16 healthy children (P<.05), whereas antioxidant enzymes were not significantly affected. Both medically controlled and intractable children with normal MRI had higher activities of superoxide dismutase than those of controls (P<.05). The activity of superoxide dismutase in epileptic patients with structural abnormality did not significantly change as compared with controls. Activity of glutathione peroxidase in all of the epileptic children was not significantly different from controls. The activity of antioxidant enzymes or plasma malonyldialdehyde levels did not correlate with duration of epilepsy, frequency of seizures (> one seizure per month or not), and the presence or localization (focal, multifocal, or generalized) of electroencephalographic or MRI abnormalities. Increased plasma lipid peroxidation may be causally related to the presence of structural abnormality rather than ongoing epileptic activity or therapy status.Öğe Neuropeptide Y alters stress-induced changes in trace element concentrations of brain in chronically immobilized rats(Wiley-Liss, 2004) Karakoc, Y; Turhan, S; Yildirim, EA; Mengi, M; Yurdakos, E; Barutcu, UBCentral administration of neuropeptide Y (NPY) produces anxiolytic-like behavioral responses in the conflict test, elevated plus maze, fear-potentiated startle paradigm, and in the chronic immobilization stress. Exogenously administrated NPY also protects against the anxiogenic effects of corticotropin-releasing factor. In the present study, we aimed to determine the effects of centrally administered NPY on the trace element disturbances in brain tissues (frontal and temporal lobes and brain stem) and the other major organs including liver, spleen (zinc [Zn]-, copper [Cu]-, and iron-rich tissues), kidney, and stomach in chronically immobilized rats. The immobilization stress was performed in special cages in which the animals were not able to move. The rats in chronic stress and chronic stress + NPY groups were kept in the cages daily for 7 min for 15 consecutive days. Intracerebroventricular (ICV) cannulas were placed to the right lateral ventricles of the rats by using stereotaxic method. In the control and chronic stress groups, 5 muL of saline (NaCl 0.9%), and in the chronic stress + NPY group, 8 mug NPY/5 muL saline solutions, were administered into the brain via ICV cannula, respectively. Controls and immobilized rats were decapitated 30 min after the injections were over and samples of tissue were taken. Zn, Cu, and iron levels of the frontal lobe, temporal lobe, brain stem, liver, spleen, kidney, and stomach were determined by flame atomic absorption spectrophotometer. Zn and Cu levels were significantly increased in the frontal lobe, temporal lobe, and brain stem in response to chronic immobilization stress daily for 7 min for 15 consecutive days. The administration of NPY inhibited the elevation of Zn in these three parts of brain but did not affect the elevation of Cu in the frontal lobe and brain stem. Increases in Zn and Cu levels of frontal, temporal lobes, and brain stem may be related to induction of MT-I mRNA expression by chronic immobilization stress, and NPY may affect this induction of MT-I, altering corticotropin-releasing factor release in the stress conditions.
