Occurrence of ubiquitin during spermiogenesis in Chara vulgaris.

Experiments with an anti-ubiquitin antibody proved the presence of ubiquitin in spermatids at all spermiogenesis stages in Charta vulgaris. Its level increased before marked ultrastructural changes of spermatids correlated with disappearance of somatic proteins (histones) and appearance of protamine-type generative proteins. The obtained results seem to confirm our earlier hypotheses concerning a significant role of ubiquitin-proteasome system in Chara spermatozoid differentiation.

Expression of proteins: D1 cyclin and Ki-67 in papillary thyroid carcinomas.

The aim of the study was an evaluation of expression of D1 cyclin and Ki-67 proteins in tissue of human papillary thyroid carcinoma (PTC) in a group of papillary microcarcinomas and in a group of PTC with a degree of staging higher than pT1a in TNM classification. We performed immunohistochemical staining and found no statistical differences between groups. These results suggest that changes of expression of D1 cyclin are an early event in tumorigenesis.

Disappearance of 3H-leucine incorporation circadian rhythm induced by symplasmic isolation of Chara vulgaris antheridium from thallus.

Autoradiographic research with the use of 3H-leucine demonstrates that circadian rhythm of protein synthesis characteristic of manubria at the proliferative phase of spermatogenesis in Chara vulgaris disappears after symplasmic isolation of antheridium from thallus during the time preceding block of DNA endoreplication in manubria following initiation of spermiogenesis insensitive to light.

Autoradiographic studies on mucilage synthesis in Chara vulgaris antheridium with the use of 3H-fucose in total darkness and light.

Autoradiographic studies with 3H-fucose have shown that this precursor of polysaccharide compounds is incorporated into manubria and antheridial mucilage of Chara vulgaris both in the light and in the darkness. The dynamics of this process is lower in total darkness. The decrease in overall labelling of antheridium (manubria and mucilage) reflects secondary metabolic changes both in proliferative phase and in spermiogenesis. The pulse (2 and 5 min) incubations with the isotope confirm the intensive mucilage translocation which at later developmental stages is more dynamic than at earlier ones. It can explain previously observed decrease in manubria radioactivity at later stages after long (40 min) incubation, because PAS-positive polysaccharide synthesis is simultaneous with their fast translocation to the antheridial space. The present and previous autoradiographic and cytophotometric data taken altogether confirm the assumption about a nutritive role of mucilage filling Chara antheridium during the process of spermatogenesis.

Autoradiographic studies on 3H-fucose incorporation into manubria and its translocation to antheridial space during spermatogenesis in Chara vulgaris L.

The internal space of antheridium in Chara vulgaris L. is filled with the PAS-positive polysaccharide mucilage. It is produced and secreted by non-generative, polyploidal cells--manubria. Autoradiographic studies with the use of 3H-fucose have shown that this precursor is incorporated into polysaccharidial compounds at the manubrium surface. The dynamics of this process is different in proliferative phase than after symplasmic isolation of antheridium. The translocation of mucilage into antheridial space is very intensive, especially at the older developmental stages of antheridium. The data obtained after 12-hour postincubation indicated secondary metabolic changes of mucilage. The decrease in total radioactivity per investigated section is most intensive by the end of spermatogenesis. These facts seem to confirm the assumption about nutritive role of mucilage filling Chara antheridium during the process of spermatogenesis.

Differentiated reaction of different types of antheridial cells in Chara vulgaris to the changes in light conditions during 24 hours.

Circadian rhythm of activity of 3H-leucine incorporation into antheridial cells of Chara vulgaris, in natural photoperiod was compared with changes in mitotic activity of antheridial filament cells which form spermatozoids. Three types of cells functionally connected with each other i.e. manubria, capitular cells and antheridial filaments indicate high amplitude (80-90%) changes in circadian translational activity and some similarities in their course. The shield cells are characterized by small circadian changes in translational activity in the range of 15-30% and their different rhythm. Manubria, which are the secretive cells indicated the highest dependence of the dynamic of translational activity on the time of day. Their high activity overlaps light phase, low activity--dark phase. The reaction of capitular cells to day/night change is delayed in comparison with the reaction of manubria, and that of antheridial filaments is delayed in comparison with the capitular cells reaction. The assumption was set forth that manubria play the role of oscillators (starttercells) which induce the wave of changes translocating to the other cells functionally and spatialy connected with them. The course of the wave of antheridial filaments mitotic activity suggests that a distinct drop in MI in the morning may be the result of the lack of the factors necessary for initiation of the mitosis, dependent on light-induced high translational activity of antheridial cells.

Cytochemical studies on the antheridial mucilage and changes in its concentration and amount during the spermatogenesis in Chara vulgaris L.

The internal space of the antheridium in Chara vulgaris L. is filled with the PAS-positive mucilage which is of pectic nature. Morphometric and cytophotometric measurements on the semithin sections indicate that the concentration and amount of PAS-positive polysaccharides: 1) increase during the time of antheridial growth accompanying the phase of antheridial filament divisions, 2) these parameters have the maximum after spermatid formation and at the beginning of their differentiation, i.e. spermiogenesis, 3) both concentration and amount of this substance decrease at the end of spermiogenesis. A decrease in mucilage concentration is also observed in the young antheridia after 3 days of continuous darkness. The results suggest that PAS-positive mucilagenous material is a nutritive substance, accumulated in the first phase of antheridial development and utilized mainly in spermiogenesis. These substances may also be used up in the young antheridia during the lack of energy supply. The autoradiographic studies with the use of a 3H-glucose and 3H-galactose mixture seem to confirm these suggestions.

[Conservative treatment of lumbar spondylolisthesis]. / Konzervativno lijecenje lumbalne spondilolisteze.

Conservative treatment has been applied to patients suffering from low degree of lumbar spondilolysthesis, better to say those with light symptoms, or as an attempt before an operation. The treatment aims to spine functional capacity improvement and to reduce patients' unhealthy behaviour. The stress has been put to patient's active role in the treatment, and to the importance of the right choice of kinesitherapeutic exercises. In this report there is a preliminary review of observation of 28 patients suffering from lumbar spondilolystheses and conservatively treated with a definite kind of kinesitherapeutic exercises.