RESUMO
The aim of this study was to evaluate the effect of hydrated carbon 60 fullerene (C60HyFn) on ram semen quality during cryopreservation. Three ejaculates from each of seven Akkaraman rams were collected using an artificial vagina during the nonbreeding season and pooled. Pooled semen samples were divided into 10 equal parts and diluted with tris + egg yolk extender not containing (control) and containing 100, 200, 400, and 800 nM and 1, 5, 10, 20, and 40 µM C60HyFn at 37°C. After addition of 5% glycerol and an equilibration process for 3 hours, the samples were frozen in 0.25-mL straws in an automatic freezing device at -140°C and stored in a liquid nitrogen container. Straws were thawed 24 hours after freezing and analyzed immediately with no incubation period. Motility, kinematic parameters, abnormality, vitality, hypo-osmotic swelling test (HOST), and oxidative stress levels were analyzed in thawed semen. Compared with the control, 200, 400, and 800 nM and 1 and 5 µM C60HyFn doses increased motility and HOST values and decreased the dead sperm rate. When compared with the control, addition of C60HyFn significantly decreased malondialdehyde levels (between 200 nM and 40 µM doses) and significantly increased glutathione peroxidase (between 800 nM and 40 µM doses) and catalase (between 1 and 40 µM doses) activities. In conclusion, results of this study show that the C60HyFn nanoparticles are nontoxic to ram semen and their supplementation in the extender is beneficial to sperm motility and membrane integrity after freeze-thawing.
Assuntos
Fulerenos , Preservação do Sêmen , Animais , Carbono/farmacologia , Criopreservação/métodos , Crioprotetores/farmacologia , Feminino , Congelamento , Fulerenos/farmacologia , Masculino , Sêmen , Análise do Sêmen , Preservação do Sêmen/métodos , Preservação do Sêmen/veterinária , Motilidade dos Espermatozoides , EspermatozoidesRESUMO
This report reviews the way in which classical embryology is taught and interpreted at the Buca Faculty of Education, in Dokuz Eylul University (Turkey). This university is one of the leading teacher-education institutions in Turkey. My course is taught with appreciation of the fact that students are thinking ideologically rather than scientifically with regard to creationism and evolution in both cognitive and educational processes. However, this ideological orientation, along with lack of classroom time and material resources, hinders my goal of a student-centered education. Being flexible with regard to philosophical and metaphysical issues on which concepts of evolution and creationism are in conflict, is constructive for student development and represents the approach I endeavor to pursue.