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Zuzana Jirsová

Publications and source records attributed to Zuzana Jirsová.

4 recordsLinked to original sources
PubMed2004

Altered spermatogenesis in the hypodactylous rats.

Germinal epithelium of seminiferous tubules in adult, infertile hypodactylous males displays significant reduction in the number of germ-line cells. Detection of apoptosis in the germ-line cells during postnatal differentiation was performed to elucidate the mechanism of the decreased number of germ cells in the testes of adult rats. Evaluation of DNA fragmentation and expression of activated caspase-3 in germ cells did not confirm marked germ cell death during the onset of spermatogenesis as a main cause of significant reduction of germ cells in Hd/Hd testes of adult males. The primary cause of spermatogenesis defect seems to be rather associated with a disorder in the cell cycle regulation and interrelation of germ-line cells with Sertoli cells.

Animals↗
PubMed2002

Indicators of functional differentiation of the chick embryonic kidney.

Relevant indicators of the functional capability of the embryonic kidney were tested in the chick mesonephros chosen as an ideal model accessible to direct observation in vivo. Evidence of glomerular filtration (GF) was checked up by the arterial injection of 2% lissamine green (LG) followed by measurement of the LG passage time on days 5, 6 and 7. Presence of the electrogenic transport was investigated by determining the transepithelial potential difference (TPD) which distinguished proximal and distal tubules of the 6-day nephrons. GF and tubular reabsorption could be demonstrated from day 5 by the storage of trypan blue (TB) in proximal tubules after intra-amniotic administration of the dye. The distribution of tubule staining corresponded to the proximal-distal gradient of the nephron differentiation. Activities of embrane enzymes, alkaline phosphatase and 5'-nucleotidase, were detected from day 4. They preceded the ultrastructural maturation in the differentiating proximal tubule epithelia. A semiquantitative evaluation of enzyme activities by the method of measuring of the minimum incubation time (MIT) together with the TB storage, appeared reliable and relevant indicators of the functional properties of mesonephric nephrons, suitable for distinguishing between more and less advanced stages of the nephron development.

Animals↗
PubMed2002

Histochemical demonstration of the heterogeneity of the epithelium of proximal tubules in the chick mesonephros.

Proximal tubules (PT) in 7-10-day old chick mesonephros were examined histochemically to evaluate their structural and functional properties related to the absorption capacity of the epithelium and its possible alterations leading to cystically dilated tubules (CDT). Alkaline phosphatase activity at the apical cell membrane was demonstrated in varying intensities in large PT. A similar heterogeneity was also detected in the expression of proteoglycans (Lewis(x) antigen) localized in the apical part of the epithelial cell membrane but not in the basolateral membrane parts (beta-catenin, Na(+),K(+)-ATPase). In analogy, the ability to accumulate trypan blue was found in the same cell population. We hypothesize that epithelial cells in proximal tubules of nephrons with a defective apical cell membrane cause reduced fluid absorption and subsequent overfilling and dilation of the tubules.

Alkaline Phosphatase↗