The SRM12/ADA1 Gene Sequence Inserted into Recombinant Plasmids Makes Them More Mitotically Stable in Budding Yeast Cells

TheSRM12/ADA1 gene sequence inserted into a recombinant circular plasmid improves its maintenance in budding yeast (Saccharomyces cerevisiae) cells. Plasmid stabilization caused by the integrated SRM12 sequence does not require the SRM12 function complementing the srm12 mutation and depends on the orientation of the inserted sequence in the vector. This stabilization is mainly due to a decrease in spontaneous plasmid underreplication/copy loss rather than an increase in the fidelity of mitotic plasmid segregation.     

Immunoelectrophoresis analysis of the antigenic composition of E. coli K12 hybrids which acquired the serological specificity of S. newcastle and S. flexneri

Genetic and immunoelectrophoretic studies confirm earlier data on the presence of 2 specific antigens of acidic nature in S. newcastle; one of them is a specific thermolabile K-antigen responsible for type IV specificity of these bacteria. The data concerning the differences in the genetic determinants controlling the synthesis of O- and K-antigens in S. newcastle have been obtained. S. newcastle O- and K-antigens did not react with S. flexneri in the group serum system 3, 4, which indicates that S. newcastle are serologically isolated and form a separate taxonomic group of dysentery bacteria. The existence of cross reactions between S. flexneri and S. newcastle due to the presence of neutral R-core antigens common to these 2 species has been shown . Immunoelectrophoresis in agar is the most promising and informative method in genetic and chemical studies of the antigenic structure of bacteria.     

Phagocytosis activity of monocytes and macrophages in patients with plasmacytoma

The capacity to phagocytosis in monocytic macrophages was investigated in 24 patients with plasmocytoma. The investigation of this capacity was made by using short-term cultures with sheep erythrocytes loaded with antibodies and complement. In comparison to the control group the percentage of phagocyting macrophages was lowered in 16 from 24 patients. This impairment of the function of monocytic macrophages seems to be bound neither to the type of plasmocytoma nor to the stage of disease. Among other things, the nature of cell defect is discussed. The necessity of further investigations is emphasized.     

Electron microscopic evidence of circular molecules in 9-S globin mRNA from rabbit reticulocytes

9S globin mRNA prepared by the proteinase K method from polysomes of rabbit reticulocytes consists of 40% circular molecules as revealed by electron microscopy, if spreading of the molecules is performed from a solution of 50% formamide, 0.5 M NaCl, 25 mM Tris, 10 mM EDTA, pH 8, after 16 h incubation at 42 °C. We assume a noncovalent nature of the circularization because of the fact that a total transformation into the well known linear form occurs if strong denaturing conditions for spreading were used. The biological significance of the circular globin mRNA molecules is unknown.     

Electron microscopy for the diagnosis of tumours.

The role of leukocyte transfusions in the prevention and treatment of infections in adults with granulocytopenia was investigated. Leukocytes were obtained from healthy volunteers by continuous-flow centrifugation. Histocompatibility antigen (HLA)-matched leukocytes were used to assess the prophylactic value of leukocyte transfusions. Seven patients with acute myelogenous leukemia received HLA-matched leukocytes during the period of maximal granulocytopenia associated with initial remission induction therapy; 20 concurrently treated patients who did not receive leukocyte transfusions were the control group. The patients receiving HLA-matched leukocytes had significantly fewer (P = 0.043) infectious episodes (not bacteriologically proven) during the study period, and remission occurred in 5 of the 7, compared with 10 of the 20 controls. In addition, 52 series of two or more ABO-compatible transfusions were given to 50 patients with proven infection or elevated temperature presumed due to infection and a granulocyte count of less than 0.5 X 10(9)/L. Response, indicated by a decrease in temperature, occurred in 23 patients. Leukocyte transfusions thus have an important adjuvant role in the management of patients with severe granulocytopenia.