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Biomedical subjects

A Siwicki

Publications and source records attributed to A Siwicki.

5 recordsLinked to original sources

Cell-mediated immunity in yellow forms of rainbow trout.

The aim of the present study was to investigate possible pleiotropic effects of the genotypes controlling the palomino and albino coloration on blood phagocyte and lymphocyte activity. The results showed that the wild coloured trout has a higher metabolic and potential killing activity of blood phagocytes, compared to albino and palomino coloured trout. The proliferative response of blood lymphocytes stimulated by ConA or LPS indicated a similar pattern. The results showed that lymphocyte proliferation was statistically significantly higher in wild coloured trout, compared to albino and palomino trout.

Animals↗

In vitro effect of levamisole on the neutrophil activity in rainbow trout (Oncorhynchus mykiss).

An in vitro immunization and cultivation method for fish spleen organ section was used to investigate the effects of levamisole on the neutrophil activity. After 10 days of culture with either 50 micrograms/ml, 25 micrograms/ml, 5 micrograms/ml or no levamisole in the media, the nonspecific defense reactions were measured by determining the metabolic activity of neutrophils by using the nitroblue tetrazolium test, and phagocytic and adherence indexes by incubating the fish cells with suspensions of formalin-killed Staphylococcus aureus. Elevations were found in nonspecific cellular defense in the 5 micrograms/ml levels of levamisole. The 25 micrograms/ml levels instigated a slight elevation in nonspecific cellular defense and the 50 micrograms/ml levels suppressed all indicators, whether levamisole was given alone or combined with Yersinia ruckeri O-antigen or DNP-Ficoll. These antigens are themselves nonspecific cellular defense stimulators, and a synergistic effect was evident when combined with 25 micrograms/ml and 5 micrograms/ml levels of levamisole.

Animals↗

Effects of the herbicide Roundup on the ultrastructural pattern of hepatocytes in carp (Cyprinus carpio).

Experimental studies were performed on healthy, 80-100 g carp (Cyprinus carpio). Fish were exposed by emersion in Roundup (205 mg of glyphosate/l or 410 mg of glyphosate/l) in concentrations of 40- to 20-fold lower than those used in practice. Electron microscopy revealed that the herbicide caused appearance of myelin-like structures in carp hepatocytes, swelling of mitochondria and disappearance of internal membrane of mitochondria in carp at both exposure concentrations. It means that Roundup was harmful to carp when used in applied concentrations. Results of these studies enhance our knowledge of ultrastructural pathomorphology of fish organs following exposure to Roundup.

Animals↗

Effects of dimerized lysozyme (KLP-602) on the cellular and humoral defence mechanisms in sheatfish (Silurus glanis): in vitro and in vivo study.

This study examined the effects of the dimerized lysozyme (KLP-602) on the immunocompetence cell activity in sheatfish (Silurus glanis) and its influence in vivo on the non-specific defence mechanisms and protection against motile aeromonad septicaemia (MAS). The in vitro study showed that the lysozyme dimer (KLP-602), at concentrations between 5 and 50 micrograms/mL of medium significantly (P < 0.05) increased the respiratory burst activity and potential killing activity of pronephric macrophages, as well as the proliferative ability of pronephric lymphocytes stimulated by ConA and LPS. The in vivo study showed that injecting lysozyme dimer (Lydium-KLP) intraperitoneally at doses of 50 micrograms/kg bw stimulated cell-mediated and humoral-mediated imunity. On day 5, after application of Lydium-KLP in vivo, a statistically higher (P < 0.05) respiratory burst activity and potential killing activity of blood and pronephros phagocytes were observed. A higher proliferative ability of blood and pronephros lymphocytes stimulated by Concanavaline A (ConA) or lipopolysaccharide (LPS) was also observed. At the same time, the myeloperoxidase activity in the PMN cells and the lysozyme activity and total Ig levels in serum were significantly higher (P < 0.05), compared to the control group. A challenge test with Aeromonas hydrophila showed that dimerized lysozyme increased the protection against MAS. Dimerized lysozyme stimulates non-specific cellular and humoral mechanisms and protection against MAS in sheatfish.

Animals↗