72 research outputs found
The Physiological and Biochemical Mechanisms Providing the Increased Constitutive Cold Resistance in the Potato Plants, Expressing the Yeast SUC2 Gene Encoding Apoplastic Invertase
The expression of heterologous genes in plants is an effective method to improve our understanding of plant resistance mechanisms. The purpose of this work was to investigate the involvement of cell-wall invertase and apoplastic sugars into constitutive cold resistance hypothermia conditions compared to WT-plants. This fact allows us to consider cell-wall invertase as a enzyme of carbohydrate metabolism playing an important regulatory role in the metabolic signaling upon forming increased plant resistance to low temperature. Thus, the potato line with the integrated SUC2 gene is a convenient tool to study the role of the apoplastic invertase and the products of its activity during growth, development and formation constitutive resistance to hypothermia
Parietal and occipital hair loss patterns in initial stages of androgenic alopecia in men
Background. The initial stages of androgenetic alopecia in men are characterized by a variety of clinical manifestation in the parietal or occipital scalp regions. However, the differences in the pathogenesis of hair loss patterns are not well understood, selective treatment has not been developed.
Aims. Trichological characteristics of patients with initial stages of androgenetic alopecia with identification of genetic and non-genetic factors that determine the hair loss in the different scalp regions, and their response to conservative therapy.
Materials and methods: Trichograms were photodocumented using an AramoSG microcamera (Republic of Korea). The genetic factor was analyzed by mini-sequencing of single nucleotide polymorphisms rs929626, rs5919324, rs1998076, rs12565727, rs756853. The non-genetic factors study included hormonal status (total and free testosterone, dihydrotestosterone, 17OH-progesterone, dehydroepiandrostenone, SHBG) and blood content of trace elements (Mg, Ca, Zn, Cu, Se, Fe) and vitamins (B12, D, E, folic acid). Conservative treatment was topical application of a minoxidil 5% (twice-a-day, 4 months) and a micronutrient deficiencies personalized correction.
Results. The study included 47 man with initial stages of androgenetic alopecia. Their trichological examination showed two patterns, consisting a predominant decrease in the hair density and diameter in the parietal and occipital scalp regions, which were subgroups formation criteria. An intergroup comparison revealed similar genetic risk, while hormonal parameters (increased dihydrotestosterone levels, a decrease in free testosterone) characterized the subgroup with parietal hair loss pattern. Also, a multiple deficiency of Zn, Cu, Se and vitamins B12, D, folic acid was detected in all patients. Subsequent conservative treatment had a positive effect in patients with parietal hair loss pattern, while in patients with occipital pattern no significant response was observed.
Conclusions. The study develops ideas about differences between androgen-dependent parietal and androgen-independent occipital hair loss patterns in the initial stages of androgenetic alopecia, which requires different approaches to their conservative therapy
Development of a Reagent for Evaluation of Incipient Immune Response to the Live Plague Vaccine
Objective of the study is to develop a reagent for the detection of lymphocytes with Yersinia pestis F1 antigen receptors. Materials and methods. Utilized have been: live plague vaccine based on the strain of Yersinia pestis EV NIIEG, formalin killed suspensions of microorganisms - Y. pestis , 3123, Y. enterocolitica O9 H-383 serovar, Y. pseudotuberculosis O1 2841 serovar; acetaldehyde-immobilized capsular antigen of Y. pestis F1 (obtained applying Baker methodology), lipopolysaccharide of Y. pestis K1, and bovine erythrocytes. Bovine erythrocyte F1 sensibilization has been performed using rivanol. Lymphocytes from blood have been isolated in density gradient ficoll-verografin 1.077. Lymphocytes with Yersinia pestis F1 antigen receptors have been detected by means of reagent adhesion onto the isolated lymphocytes. F1-free erythrocytes serve as controls. After the exposition, 7 evaluations of specificity to F1 and the lymphocytes, binding control reagent, have been carried out. Deployed have been 8 rabbits, immunized with live vaccine EV, and 2 rabbits, immunized with inactivated vaccine EV. Examined have been EV-vaccinated 5 persons. Results and conclusions. Identified is optimum sensibilizing dose of F1 antigen (250 µg/ml). Specificity of lymphocytes with receptors to F1 is demonstrated in inhibition experiments applying homologous and heterogeneous antigens. Lymphocytes with receptors to F1 (LRs) have been detected in peripheral blood of all rabbits and humans, immunized with vaccine EV. LRs have been registered since day 2 till day 35 in the rabbits, and in humans - since day 2 till day 14 after vaccination. It is shown that in case of revaccination of humans, LRs emerge and disappear earlier, than in case of primary immunization
Use of analytic solutions in the statement of difference boundary conditions on a movable shoreline
Solutions to initial boundary value problems are constructed for the shallow water equations in the form of series locally convergent in the neighbourhood of a movable water–land boundary for an arbitrary bottom relief. The motion law and the velocity of this boundary are determined for various wave–shore interaction modes. The obtained results of analytic study of the solutions are used for the development of approximations of boundary conditions on the movable shoreline. Test problems are numerically solved using an explicit predictor-corrector scheme of the second order of approximation on adaptive grids retracing the position of the water–land boundary. The results of these calculations are presented
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