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The experience with operative treatment of 974 patients with chronic paraproctitis has been summarized. After the operations for intrasphincter fistula, 1% of the patients developed a disease recurrence, 0.5%--incompetence of the anal sphincter; for transsphincteric fistula--2.6 and 1.9%, respectively, for extrasphincteric fistula--5.7 and 5.2%. A fistula excision into the intestinal lumen is an operation of choice in intra- and transsphincteric fistula. In extrasphincteric fistula, fistula excision, plastic transfer of mucosa for closure of its internal opening with preservation of the anal sphincter should be performed. In presence of the extensive scars and purulent leaks, a ligature should be added to fistula excision.

The results of operative treatment of hemorrhoids in 1437 patients are presented. After hemorrhoidectomy with restoration of the rectal mucosa, the decrease in incidence of complications after operation was noted.

O2-generation rate (Vo2-) in microsomal, mitochondrial and nuclei liver membranes was measured by ESR method, by accumulation of stable nitroxide radicals. These Vo2- values were compared with Cu, ZnSOD and MnSOD activities after 2 hours ischemia and 24 hours reoxygenation. O2- radicals generated by electron transfer chains are concluded to damage mainly during the ischemia, but not the reoxygenation.

The alkaline phosphatase activity was studied in embryonic lung human fibroblasts grown in vitro. The total enzyme activity per flask was constant during the log-phase of culture growth to increase significantly after confluence. The increase in the activity did not depend on the rate of culture growth, and was seen to start after the mean density equal to (37.5 +/- 5.9) X 10(3) cells/cm2 flask surface. The stimulation of cell growth may presumably slow down the synthesis of alkaline phosphatase, which resumes after the contact inhibition of DNA replication.

The reasons for the decreased stability of glucose-6-phosphate dehydrogenase in transformed human cells were investigated. The enzyme stability was found to be dependent on its subunit composition; the dimeric form possessed a lower stability in comparison with the tetrameric one. An addition of NADP to cell extracts which had partly lost their glucose-6-phosphate dehydrogenase activity, resulted in reactivation and stabilization of the enzyme. The constants for a forward (k1) and back (k2) reactions during stabilization are equal to 2.87 X 10(-3) and 5.77 X 10(-1) s-1, respectively. The inactivation and reactivation kinetics suggest that the enzyme destabilization may also occur inside the cells. The cells contain more than 40% of glucose-6-phosphate dehydrogenase molecules in an inactive form. A mechanism of destabilization and inactivation of glucose-6-phosphate dehydrogenase is proposed, which consists in NADP hydrolysis and enzyme decomposition to inactive monomers which are less stable to proteolysis.

A new strain of the embryonic human fibroblasts L-68 was obtained and thoroughly characterized. It completely met all the requirements of the International Committee on the Cells Cultures. This strain can be recommended as a substrate for production of viral vaccines, diagnostic preparations and for research purposes.

A study was made of the relationship between the activity of alkaline phosphatase and the proliferation of cultured human cells with different replicative potentials. It is shown that alkaline phosphatase plays a role as one of endogenic stimulators of cellular proliferation. The ageing of diploid cells is accompanied by a decrease in the enzyme activity. Maximum activity was observed during a period of logarithmic cell growth. Addition of placental alkaline phosphatase to the synchronized diploid cells stimulated DNA synthesis in the S-phase of the cell cycle. Heteroploid cells with a high growth rate possessed a 30-100 times higher alkaline phosphatase activity than in the diploid cells. Under certain conditions alkaline phosphatase may presumably function as a proteinkinase.

The subcellular distribution of alkaline phosphatase in normal and transformed cultivated human cells was investigated. The total activity of alkaline phosphatase in the transformed cells exceeds that in normal cells 10- (or more) fold and is sharply increased with a rise in the cell population density. The proliferating cells have the same specific activity of alkaline phosphatase in the mitochondrial-lysosomal and microsomal fractions. The transition of normal cells to the G0-phase of the cell cycle is accompanied by an increase in the total enzyme activity and selective accumulation of alkaline phosphatase in the microsomes. An addition of exogenous alkaline phosphatase to intact cells leads to the stimulation of DNA synthesis and to changes in cell morphology. The data obtained suggest that alkaline phosphatase can participate in the destabilization of the cytoskeleton and stimulate cell proliferation. However, in normal cells the selective accumulation of the enzyme in the membranes may hamper its biosynthesis. the activity of alkaline phosphatase thus does not reach the level sufficient for unrestricted cell growth.

The causes for different stability of glucose-6-phosphate dehydrogenase in two heteroploid cell strains and in the diploid cell strain of human embryo lungs were investigated. The thermostability of glucose-6-phosphate dehydrogenase was shown to be dependent on the coenzyme (NADP) concentration and to be coupled with the activity of alkaline phosphatase. In diploid and heteroploid cell extracts possessing a low alkaline phosphatase activity glucose-6-phosphate dehydrogenase reveals a high stability. In heteroploid cell extracts having a high activity of alkaline phosphatase a fast hydrolysis of NADP and a decrease of glucose-6-phosphate dehydrogenase stability are observed. Inhibition of alkaline phosphatase by levamisole prior to cell disruption does not increase the stability of glucose-6-phosphate dehydrogenase. Presumably destabilization of glucose-6-phosphate dehydrogenase mediated by alkaline phosphatase occurs in intact cells and is an essential mechanism controlling the enzyme activity.