The Mouse Limb Anatomy Atlas: An interactive 3D tool for studying embryonic limb patterning

Background  

The developing mouse limb is widely used as a model system for studying tissue patterning. Despite this, few references are available that can be used for the correct identification of developing limb structures, such as muscles and tendons. Existing textual references consist of two-dimensional (2D) illustrations of the adult rat or mouse limb that can be difficult to apply when attempting to describe the complex three-dimensional (3D) relationship between tissues.     

Determination of the accessible surface of lysozyme and human serum albumin molecules by the total tritium labeling method

Amino acids composing an accessible surface of lysozyme and human serum albumin (HSA) globules were determined by the total tritium labelling method. A good correlation between our data on the distribution of the tritium label for the lysozyme molecule and X-ray data on the tertiary structure for this macromolecule was received. Lysozyme was used as a standard for determining the accessible surface of the globule albumin. It was shown that the accessible surface of the albumin globule is substantially more hydrophobic (average accessible surface area of hydrophobic amino acids is 130 A2 in HSA and 20 A2 in lysozyme) than in lysozyme. The HSA molecule is characterized by high values of: the accessible surface area, the ratio of extended area to the folded one, and the surface roughness index. These data indicate that the HSA molecule is less compactly packed than lysozyme.     

Terminal vascular bed of the connective tissue membrane in hypoxic hypoxia]

Morphological changes of all links of the terminal vascular bed during acute hypoxic hypoxia were studied in experiment and in postmortem material. A complex of methods was used including microdissection, injection with India ink - gelatin, clearing, silver nitrate impregnation after V. V. Kuprijanov, staining after Van Gieson and with hematoxylin-eosin, biomicroscopy and reoencephalography. Signs of desorganization of the vascular bed were revealed which manifested themselves as changes in microangioarchitectonics and diameters of vascular lumens, increased permiability of their walls with saturation of them with white and escape of its forming elements of the blood outside the limits of the vessels, as well as in destruction of the aggregate state of the blood. It considerably enlarges our knowledge of the state and changes in the vascular bed during hypoxic hypoxia.     

Comparative cytophotometric analysis of the nucleic acid content in the cardiomyocytes of normal rats and following experimental infarct

The cytophotometrical investigation of gallocyanine-chrome alum stained cardiac muscle cells allows to ascertain that a mean content of the nucleic acids calculated for a single nucleus is essentially higher in the left ventricle myocytes in comparison with the left auricle cells of healthy adult rats. These values in 1-, 2- and 3-nuclear cells of the ventricle are, respectively, 21.3, 19.3, and 18.0, and 14.1, 13.7, 13.5 of arbitrary units (a. u.) in the auricle cells. A difference in cytoplasmic RNA contents of the same cells is more significant, these values are 65.7, 116.4, and 158.9 a. u. in ventricle myocytes, and 33.4, 60.8 and 95.2 a. u. in auricle cells. The nucleic acids content in the nuclei and RNA content in the cytoplasm increase with the development of proliferation in myocytes after experimental myocardial infarction. A relative increase in the nucleic acids content in the nuclei of the same cell types reaches 50, 24, and 10% 11 days after infarction and 56, 38, and 45% 31 days after infarction. A relative increase in cytoplasmic RNA of the same cells reaches, respectively, 52, 17, and 25%, and 70, 57, and 53% 11 and 31 days after infarction. These findings evidence on the greatest synthetic activity of the single-nuclear auricle muscle cells in the process of heart restoration after infarction.     

Processes of the differentiation and reproduction of different types of muscle cells

The present review is regarding a vast evidence on reproduction, differentiation, and regenerative capacity of various muscle cells on the basis of A. A. Zavarzin's (Senior) parallelism conception. It is specially emphasized that parallelism in the subcellular organization of contractile structures of somatic and of heart muscle goes well together with a totally different principle of organization of these cellular elements (symplasts, or cells, respectively), and with different mechanisms of their histogenesis and regeneration (proliferation of, respectively, myoblasts, or immature myocytes). According to their ultrastructure and pattern of interrelation between proliferation and differentiation process, muscles of lymphatic hearts are closer to somatic muscles rather than to ordinary myocardium. Special attention is called to paradoxical situations, such as the presence of satellite-like cells in the myocardium of Decapoda, DNA-synthesizing capacity observed in the nuclei of growing somatic muscles of the silkworm, or DNA-synthesizing and chromosome-reproducing capacity of adult primate and human cardiomyocytes.