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Two-wavelength scanning cytophotometry was performed for the measurement of DNA (Feulgen reaction) and total protein content (naphthol yellow S staining) in the same cardiac myocyte. A lack of proportionality between the DNA content (i.e, cell ploidy) and protein content has been detected in ventricles of normal weight in the human heart. While the ploidy classes contained ratios of 2:4:8:16:32, the ratio of the protein content was about 2:3:5:8:17. In hypertrophic left or right ventricles, the latter ratio composed a series of doubling. Owing to this additional growth, weight of muscle tissue may be increased from 30% to twice, depending on the myocyte ploidy of a given myocardium which varies from 4 to 10c on average under normal circumstances and to 30c in some cases of hypertrophy (where c is the haploid DNA content, and, accordingly, a haploid chromosome set). Thus, one of the mechanisms of cardiac hypertrophy has been revealed which comprises the first step of the growth and often the process per se. Polyploidization of cardiac myocytes and their postmitotic growth enhance the heart weight in normal circumstances and creates a growth reserve for hypertrophy under conditions of pathology in future.

It is established by electron microscopical radioautography that sepsis results in the lowering of neutrophils bacterial capacity while their absorptive capacity is retained. Living bacteria may be released from neutrophils undergoing degradation into the environment. The same is observed when phagocytized but still living bacteria are located in phagosomes which are fused with one another and with neutrophil plasma membrane; after the destruction of the latter bacteria are released into the extracellular space. This is a negative issue for the host of the incomplete phagocytosis. Neutrophils participate more actively in the lysis of the necrotic tissues and wound cleaning than in the bacteria phagocytosis.

Lack of proportionality between DNA and protein content has been revealed in the human cardiac myocytes. The proportion 2:4:8:16 was observed in DNA of di-, tetra-, octa- and hexadeca myocytes while the protein content of the same cells was 2:3.5:5.2:7.2 in the inner layer, 2:3.5:6.5:8.9 in the central layer and 2:3.1:5.6:9.1 in the outer layer of the normal left ventricle. The protein content of myocytes of the same ploidy was higher in the inner layer than in other ones.

Electron microscopic radioautography was used to study nucleic acid synthesis in the normal fatty tissue and lipomas of different degree of maturity. Destroyed adipocytes were found in the investigated varieties of the fatty tissue. In a slow-growing Madelung's lipoma such adipocytes occurred in a greater amount than in the normal fatty tissue and nongrowing lipomas. 3H-Thymidine was mainly incorporated by endotheliocytes and pericytes, whereas Madelung's lipoma contained a greater number of labeled cells. Based on the data obtained it is suggested that the replenishment of adipocytes occurs at the expense of the proliferation of vascular wall cells.