The histology and calcification of regenerating scales in the blackspotted topminnow, Fundulus olivaceus (Storer)

The regenerating scale and tissues comprising the scale pocket of Fundulus olivaceus were examined microscopically at specific intervals. Scale removal resulted in a thickening of the epidermis which persisted through the early stages of regeneration. This thickening was due in part to the appearance of columnar basal cells which divided producing cells that became mucous cells and squamous cells. The scale regenerated as a relatively large plate of bone which first appeared between layers of scleroblasts on the floor of the scale pocket and then grew producing circuli and radii. By the fourth day of regeneration, calcium was observed in the cytoplasm of the scleroblasts and at randomly distributed foci in the osseous portion of the scale. The osseous layer was completely calcified by 15 days of regeneration.     

Effect of specific antibodies on active immunity development in those inoculated with an antirabies vaccine

The study of the effect of gamma globulin introduced in different doses (0.5 and 0.25 ml/mg) in combination with Fermi rabies vaccine (observations on humans were made) and with cerebral rabies vaccine inactivated by UV irradiation (in animal experiments) demonstrated that the injection of the higher doses of gamma globulin resulted in lower geometrical mean of antibody titers. Therefore, in combined administration of rabies vaccine and gamma globulin for postexposure rabies prevention it is advisable to reduce the dose of gamma globulin by one-half.     

Study of human erythrocyte membrane proteins by 2-dimensional electrophoresis

Fractionation of human erythrocyte membrane proteins was performed using a modification of two-dimensional gel electrophoresis described by P. O'Farrel with isoelectric point plotted against molecular mass. All major erythrocyte proteins, including high molecular weight proteins, such as spectrin and band 3 protein, identified by one-dimensional sodium dodecyl sulfate gel electrophoresis, were visualized by silver staining of two-dimensional gels. All in all about 50 polypeptides were distinguished on two-dimensional electrophoretic patterns. Preliminary protein map was developed.     

Reversing the detrimental effect of adriamycin on skin grafts in rats

We evaluated in a rat model the effects of a homologous fibrin glue in reversing the effects of Adriamycin on adherence and take of skin grafts. A total of 40 male Fisher rats were used in the study. During the first phase of the experiment, the animals were assigned to either group I (N = 10) receiving normal saline or group II (N = 10) receiving 6 mg/kg Adriamycin by tail vein injection 24 hours before surgery. Skin grafts with and without fibrin glue were placed over wounds in the backs of the animals and adherence was measured at 24 and 48 hours. In the second phase (N = 20), the experiment was repeated, this time evaluating the total area of skin graft take at 7 days. Fibrin glue was found to increase adherence and take of skin grafts in all Adriamycin-treated animals.     

Chemotactic assay for biological effects of silver nanoparticles

A method is proposed for assessing the biocidal efficacy of water-dispersed nanoparticles of silver. It is based on negative chemotaxis of the plasmodia of the slime mold Physarum polycephalum. Biocidal and repellent effects were compared for silver nanoparticles, Ag⁺ ions, and AOT in solution and in the agar gel. In such characteristics as increasing the period of auto-oscillations of contractile activity, decreasing the area of spreading on substrate, and substrate preference in spatial tests, silver nanoparticles proved to be substantially more effective than Ag⁺ and AOT. The lethal concentrations of the nanoparticles were close to those found earlier for bacteria and viruses. The chemotactic tests allow quantitative assessment of the biological reaction and monitoring its dynamics; in resolution, they are superior to the tests based on the lethal action of biocidal agents.     

RNA and DNA in developing retinae: comparison of a normal with the degenerating retinae of C3H mice

Abstract— The Nucleic acids were measured in developing retinae of normal (DBA) mice and those afflicted with an inherited degenerative disease (C3H). The content of RNA in normal and C3H retinae increased to a maximum at 5 days of postnatal age. Thereafter, that of C3H retinae declined to a value lower than the normal. The content of DNA in normal and C3H retinae was maximal at 10 and 5 days of postnatal age, respectively. By 20 days, it declined in both retinae to nearly adult values. The DNA/RNA ratio of normal adult retinae was about 3, while that of C3H adult retinae was nearly 1–5. It is proposed that the photoreceptor cells possess a smaller cytoplasmic volume and a larger DNA/RNA ratio than the cells of the inner retina. The loss of DNA in developing normal and C3H retinae appears to result from cellular death. It was calculated that approximately 1 million cells in normal and 6 million cells in C3H retinae disappear during development. Cellular death in C3H retinae may not be restricted to the photoreceptor population.