Yazar "Yapar, SB" seçeneğine göre listele

Listeleniyor 1 - 2 / 2
  • Küçük Resim Yok
    Öğe
    Glutathione and free sulphydryl content of seminal plasma in healthy medical students during and after exam stress
    (Oxford Univ Press, 2005) Eskiocak, S; Gozen, AS; Yapar, SB; Tavas, F; Kilic, AS; Eskiocak, M
    BACKGROUND: It has been reported that there is a relationship between stress and infertility. The mechanisms of stress-related semen quality alterations have not been fully elucidated. In the present study, we investigated the effect of examination stress on seminal glutathione and free sulphydryl content and sperm quality. METHODS: Semen samples were collected from 34 healthy volunteers who were students of medical school in the fourth semester just before (stress period) and 3 months after (non-stress period) their final examinations. Their psychological examination stress was measured by the State Trait Anxiety Inventory (STAI) questionnaire. After standard semen analysis, semen samples were centrifuged at 10 000g for 15 min. Glutathione and free sulphydryl concentration of seminal plasma were measured. RESULTS: During the period of examination stress, the glutathione and free sulphydryl content of seminal plasma and the motility index of spermatozoa were significantly lower, whereas the percentage of morphologically abnormal spermatozoa was higher, than during the non-stress period (P < 0.001, for all). An association between seminal plasma glutathione and motility index was observed at both periods (P < 0.05 and P < 0.01, respectively). CONCLUSIONS: This study demonstrated that glutathione and free sulphydryl levels in seminal plasma decreased in subjects undergoing examination stress. Furthermore, poor sperm quality may be due to loss of glutathione and free sulphydryl content of seminal plasma.
  • Küçük Resim Yok
    Öğe
    Inhibition of iNOS with S-methylisothiourea was impaired in wound heating in caustic esophageal burn
    (Elsevier Ireland Ltd, 2005) Basaran, UN; Eskiocak, S; Altaner, S; Ture, M; Yapar, SB
    Objective: Stricture formation is a late complication of caustic esophageal burn, which is a common problem in childhood. For this reason, this experimental study was designed to observe the possible effect of nitric oxide on heating and fibrosis formation in caustic esophageal burns. Materials and methods: The rats were divided into five groups. Group A (n = 12) received sham burn and treatment with saline injection. Group B (n = 34) received caustic burn. Rats in group C (n = 31), were given water supplement with 10 g/L L-arginine that was started 24 In preoperatively and continued until postoperative day 4. In group D (n = 21), S-methylisothiourea (SMT, specific inducible nitric oxide synthase (iNOS) inhibitor), was injected at a dose of 3 mg/kg i.p. at 30 min before caustic burn, and similar dose was reinjected immediatety after caustic burn. SMT 6 mg/kg/day injections continued for 4 days Long. In group E (n = 22), N omega-nitro-L-arginine (L-NNA, nonspecific nitric oxide synthase (NOS) inhibitor) was injected at a dose of 15 mg/kg i.p. at 30 min before caustic burn, and similar dose was reinjected immediately after caustic burn. L-NNA 30 mg/kg/day continues for 4 days. Results: Dead rates were significantly higher in group Ethan in groups A-D. The mean hydroxyproline levels in esophageal. tissue were significantly lower in groups A and B than in group D. Histopathologically, tissue damage scores in the esophageal tissue were higher in group D than in groups A-C. Conclusions: Inhibition of iNOS with SMT was impaired in wound heating due to caustic esophageal burn and provoked collagen accumulation at a later period. Those effects may due to inhibition of antioxidant, immunomodulatory and antifibrotic effects of NO. (c) 2004 Elsevier Ireland Ltd. All rights reserved.