Relationship between proliferation of Ehrlich ascitic tumor cells and status of the chalone system under conditions of modified photoregimen.

The effects of permanent darkness on proliferation of Ehrlich ascitic tumor cells and status of the chalone system in the tumor were studied. Chalone-containing preparations from animals exposed to different light conditions exhibited different biological effects on cell proliferation in this tumor. A relationship between biological activity of chalone-containing preparations and sensitivity of tumor cells to these preparations under conditions of modified photoregimen was revealed.

Regularities of spatial and time organization of the proliferative system of small intestinal cryptic epithelium in intact mice in the circahoralian biological rhythm of its cells multiplication.

The proliferative system of the small intestinal cryptic epithelium in intact mice in circahoralian rhythm of mitotic activity of its cells (with a 80-140-min period) is characterized by spatial and time organization. The characteristics of the studied proliferative system do not dub it in individual parts, but present new properties intrinsic of this system in general. The features are greatly similar to the features of spatial and time organization of this proliferative system in circadian rhythm of cell division.

Spatiotemporal organization of the proliferative system in small intestinal crypt epithelium of intact mice.

We studied spatiotemporal organization of the proliferative system in small intestinal crypt epithelium of normal mice. Close relationships were found between circadian rhythms of cell proliferation and their position in the crypt. These peculiarities reflected spatiotemporal organization of the crypt epithelium. The hierarchic structure of spatiotemporal organization suggests the existence of several interrelated levels (individual cells, cell subpopulations, and cells with basal and maximum levels of proliferation within subpopulation). Each level has its proper temporal and spatial characteristics. Their interaction determines spatiotemporal organization of the proliferative system in the small intestinal crypt epithelium.

[Spatial and temporary changes in sensitivity of murine proliferative system and energy exchange to typhoid fever infection]. / Prostranstvennye i vremennye izmeneniia chuvstvitel'nosti sistem proliferatsii i énergeticheskogo obmena u myshei k vozdeistviiu briushnotifoznoi infektsii.

The authors studied the spatial and temporary organization of the proliferative system and energy exchange in the small intestinal epithelium, as well as spatial and temporary changes in the sensitivity of these systems in mice to typhoid fever infection (cultured Salmonella typhi, 4446) at day and night. The small intestinal epithelial systems were found to show a spatial and time organization and a close correlation between their temporary and spatial changes after infection. The temporary organization of the proliferative system in the esophageal epithelium is more sensitive to infection in the day-time and that of the small intestinal epithelial proliferative system is more marked at night. Thus, these changes are tissue-specific. Typhoid fever infection causes a negative effect on the proliferative system of the small intestine at night and on its energy exchange in the day-time, which shows the system-specific response of the temporary organization of a biological process within the same organ. The changes in the spatial proliferative and energy exchange parameters in the small intestinal epithelium, which have been caused by the infection of animals, depend on the time of a day.

[Effects of a lymphocytic chalone-containing preparation on the mitotic activity of mouse thymocytes in vivo]. / Izuchenie vliianiia limfotsitarnogo keilonsoderzhashchego preparata na mitoticheskuiu aktivnost' timotsitov myshchei in vivo.

It has been shown that chalone-containing substance obtained from the rat spleen decreased the mitotic activity of mouse thymocytes upon its intraperitoneal administration to animals. The maximum inhibition was observed 45 min after the injection. Thus, the substance examined has the property of G2 chalone.

[Changes in the rhythms of the alpha-fetoprotein content of the blood serum of mice with hepatoma 22A and of tumor cell proliferation depending on the time of cyclophosphane administration]. / Izmenenie ritmov soderzhaniia al'fa-fetoproteina v syvorotke krovi myshei s gepatomoi 22A i proliferatsii kletok opukholi v zavisimosti ot vremeni vvedeniia tsiklofosfana.

A study was made of the content of alpha-fetoprotein (alpha-FP) in the blood serum and of proliferative processes in hepatoma 22A-bearing mice after injection of cyclophosphamide in a dose of 150 mg/kg at varying time of 4-day tumor growth. The data obtained indicate that the time of appearance of alpha-FP in the blood, the pattern of rhythmic fluctuations in protein content and in the number of DNA-synthesizing and mitotic cells of the tumor depend on the time of the cytostatic injection during the day. Besides, cyclophosphamide exerts a more powerful inhibitory effect on the content of alpha-FP in the blood serum and less powerful on the proliferative processes in hepatoma 22A.

[State of the temporal organization of the system of cell reproduction in rat tissues under hypokinesia]. / Sostoianie vremennoi organizatsii sistemy reproduktsii kletok v nekotorykh tkaniakh kyrs v usloviiakh gipokinezii.

The study of time parameters of cell kinetics in the rats exposed to 34-day hypokinesia showed that changes in cell reproduction developed in rapidly and slowly renovating cells in a different way. The DNA synthesis and mitotic division were drastically inhibited in liver cells; the duration of the premitotic period of the mitotic cycle was significantly reduced in the cryptal epithelium of the small intestine. Hypokinesia did not cause important changes in the phasic structure of diurnal rhythms of cell division in the tissues tested and, consequently, did not lead to changes in the mechanisms of time organization of the cell reproduction system. It is concluded that the state of motor activity of animals is not the major time cue for cell division processes.