Conformational changes in the heat-denatured nucleotide complex of human lymphocytes on subsequent cooling

The microfluorometric technique allowed an assay of the chromatin state from binding of acridine orange in studies on the kinetics of conformational changes in the nucleoprotein complex (NP) of human peripheral blood lymphocytes. Extraction of F1 histone fraction with 0.01 N HCl (pH 2) substantially altered (decelerated) conformational changes in the NP complex. Extraction of F1, F2 and F3 histone fractions with 0.25N HCl (pH 0.6) led to a more pronounced deceleration of the kinetics of conformational changes. The latter ones were decelerated as well when the process was run in a more viscous medium (e. g. in a 70% glycerin solution). No conformational changes in the NP complex deproteinized with 0.25N HCl were revealed in a vicsous medium. In such a case the NP complex showed low F530 values and elevated values of the alpha coefficient that seems likely to suggest the nonreversible denaturation of the NP complex.     

Changes in fatty acids contents and growth characteristics in transformed oilseed rape (Brassica napus)

Spring oilseed rapeBrassica napus L. ssp.oleifera cv. HM-81 was transformed with T_L-DNA of the Ri plasmid of the agropine strainAgrobacterium rhizogenes 15834. Selfed progenies (R₂ and R₃ generations) were studied for changes in values of growth characteristics and fatty acids contents. Transformants are ‘homozygous’ for T_L-DNA. Both generations of transformants differed significantly from the nontransformed control plants in reduced length, lower number of pods per plant, lower total mass of seeds and the higher number of branches. The contents of palmitic, linoleic and linolenic acids were significantly higher in transformants when compared with the control. On the contrary, the contents of both stearic and oleic acids were in most of transformants significantly lower. Only traces of erucic acid (less than 0.05 % ) were found, both in transformed and nontransformed plants.     

The spread of the causative agent of yersiniosis in the regions of Sochi and adjacent areas

Yersinia enterocolitica sensu stricto, Y. kristensenii, Y. aldovae and Y. intermedia strains were for the first time isolated in the Sochi districts from people, synanthropic rodents and washings from vegetables. In the adjacent alpine and subalpine areas isolates were obtained from wild rodents. 86.7% of the isolated strains were assigned to the known antigenic variants; O16; O5; O6.31; O7.8 and O6.30 serovars were predominant. All the strains isolated from people belonged to biovar 1 and O5; O6.31; O6.30 and O10 serovars. Y. intermedia and Y. aldovae belonged to O1, 2a, 3 and O16 serovars respectively. Y. kristensenii could not be agglutinated with sera against type strains of Yersiniae represented in the antigenic scheme of Wauters et al.     

Induced differentiation of subpopulations of leukemic blood cells in patients with chronic B-cell lympholeukemia

M+-cell subpopulation forming M-rosettes and M(-)-cell subpopulation not forming M-rosettes were revealed in the peripheral blood of patients with B-cell chronic lympholeukemia (B-CLL) by means of mouse red blood rosette formation test. M+-subpopulation contained a larger percentage of cells expressing Ia-like antigens, as compared to M- subpopulation. On the other hand, the latter contained a significantly higher amount of cytoplasmatic immunoglobulin-containing cells. M+ appeared to be less mature than M- cells. Cells of B-CLL patients had a heterogeneous response to 12-0-tetradecanoylphorbol-13-acetate (TPA). Less mature cells with surface immunoglobulin expression did differentiate, while more mature cells containing cytoplasmatic immunoglobulins did not. Differentiation was accompanied by the acquisition of characteristics peculiar to more mature cells, i. e. cytoplasmatic immunoglobulin accumulation. Subpopulations of M+ and M- cells from each patient also had a different pattern of response to TPA: less mature M+ cells did differentiate, while more mature M- cells did not. Maturation of less mature leukemia cells, as the disease progresses, is suggested to result in a heterogeneous pattern of immunological B-CLL phenotype.     

Epithelial cells transdifferentiation into bladder urothelium in experiments in vivo

Atoplastic surgery using intestinal tissue has been used for the reconstructive therapy of the urinary tract since the mid-20th century; however, cell mechanisms of the urothelium engraftment are still unclear. Intestinal stem cells possess plasticity and, after autoplastic surgery, are presumably able to transdifferentiate into mature cells of the urinary tract. Using the preliminarily developed model for evaluating of the transdifferentiaion of somatic cells into urothelium in vivo, we found that, in syngeneic C57BL mice, epithelial Gfp-producing intestinal cells transdifferentiate into the cryoinjured bladder urothelium. Gfp was detected in the bladder tissue of recipient mice using reverse polymerase chain reaction, fluorescence and immunofluorescence. Colocalization of Her-4 protein revealed by common urothelium expression pattern and Gfp was demonstrated in few urothelial cells by double immunohistochemical staining of the bladder tissue with specific antibodies. The results obtained suggest that epithelial intestinal cells are able to transdifferentiate into bladder urothelium; however, the level of transdifferentiation is low and, presumably, cannot ensure the full functional urothelium engraftment in the case of autoplastic bladder surgery using intestinal tissue.