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The aim of this paper is to describe the case of a 10-year-old Siberian husky with a right upper lip neoplastic tumour and a metastasis to a submandibular lymph node. Histopathological examination with application of immunohistochemistry confirmed neoplastic outgrowth with an inflammatory form of histiocytoma and a high proliferative potential. Local progression of the neoplastic disease occurred despite the removal of the primary tumour and neoplastically infiltrated lymph node.
Oxidative stress has a significant impact on the quality of the mammalian semen. An excessive amount of reactive oxygen species (ROS) present in the environment of the spermatozoa, which rises as a result of prooxidative-antioxidative balance disorders, leads inter alia to a decrease of semen motility, changes in the conformation of the spermatozoa membrane, acrosome damage, decrease of mitochondrial activity, and appearance of the lipid peroxidation, which can become a cause of reduced fertility or infertility. For this reason the estimation of the influence of oxidative stress on semen can turn out to be a very useful tool in diagnostics of problems with fertility. Nowadays, in order to evaluate the intensity of the oxidative stress it is possible to use the direct method and indirect method that evaluate both the amount of ROS in the semen and the increase of changes in the spermatozoa caused by this compound. A precise analysis of the changes, resulting from prooxidative-antioxidative balance disorders with use of a suitable method of analysis is a base for accurate diagnosis.
The effect of reactive oxygen species (ROS) on spermatozoa can be twofold. Depending on their concentration, moment of activity, and exposure time, ROS can be an essential element in modulating many physiological processes or a cause of serious damage to the gametes. ROS of the greatest importance to the quality of semen are superoxide anion O₂⁻˙ and hydrogen peroxide – H₂O₂. Trace amounts of these compounds are essential for such processes as sperm maturation, capacitation, hyperactivation, acrosome reaction, and the fusion of the sperm with the oocyte. Their excess results in the development of oxidative stress, which significantly reduces the quality of sperm through the peroxidation of lipids, proteins, and other elements of cellular structure. The antioxidative system of semen limits the negative effects of oxidative stress on sperm. The proper function of the reproductive system and successful fertilization depend on maintaining a delicate balance between the amount of ROS and the activity of the antioxidant system.
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