There was executed an experimental study of the effect of salts of heavy metals (nickel, chromium, lead and zinc) entering the body by peroral route, on the morphology of the skin and its derivatives (hair follicles and sebaceous glands). The experiment was performed on C57BL / 6 mice with the use of the induction of hair follicle cycle by depilation. Under the subacute intoxication with salts of nickel, chromium and lead, there were revealed such signs of a dystrophic anagen as ectopia of granules of melanin in the dermal papilla and perifollicular tissue, enlarged channels of the hair. The duration of the anagen stage if compared with the control did not change. Under the intoxication with salts of nickel and lead there was revealed infiltration by mononuclear dermis and hypodermis. Lead acetate gave rise in the capillary congestion of the dermis, followed by diapedesis of erythrocytes and infiltration of the dermis by siderophages. In the course of the immunohistochemical study of the proliferative activity of keratinocytes of the skin integument derivatives with the use of antibodies to Ki-67, there was revealed a significant increase of proliferative activity of keratinocytes in comparison with the control under the use of a solution of zinc sulphate and sodium dichromate and its decrease with the use of lead acetate solution.
The aim of the study was to determine the temporal sequence of structural and functional reorganization of hair follicles in the skin of C57BL/6 mice after anagen induction.Material and methods. 30 male mice of the C57BL/6 inbred line were used for the study. Anagen induction was carried out by depilation of the hair shafts of the skin of the back. Mice were withdrawn from the experiment on the 1st, 5th, 9th, 15th, 19th, 28th days after anagen induction. Skin samples of the depilation area were fixed in buffered neutral formalin and examined using survey microscopy, morphometry, immunohistochemistry, and statistics.Results. The study of the morphological picture from the 1st to the 28th day after anagen induction showed that cyclic changes in the thickness of the dermis, subcutaneous adipose tissue and the structure of hair follicles occur in the skin. On the 1st day after anagen induction the synchronous entry of hair follicles into the anagen stage I was observed: hair follicles were completely in the dermis, had a rounded dermal papilla, above which, towards the epidermis, there was a proliferating follicular epithelium in the form of an expanding and elongating strand . On the 5th day, morphological signs corresponding to the stage of anagen III b were observed: hair follicle bulbs were located in the upper third of the subcutaneous tissue. The dermal papillae looked friable and enlarged, around their upper pole there was a zone of melanogenesis, a hair shaft and an internal root epithelial sheath being formed. The morphological changes on the 9th and 15th days corresponded to the anagen stage VI: the tips of the pigmented hair rods emerged from the funnels of the hair follicles to the surface of the epidermis, the hair follicles were located deep in the subcutaneous fatty tissue, reaching the subcutaneous muscle. The hair follicles had a narrow dermal papilla, a zone of melanogenesis, and the forming hair shafts had regular pigmentation. A pronounced thickening of the dermis and subcutaneous adipose tissue was noted. On the 19th day, the hair follicles were in the catagen VI phase: two-row bag-like structures were observed, forming capsules of the secondary hair germ). They surrounded the keratinized brush-like depigmented proximal ends of the hair shafts. Hair follicles with a rounded dermal papilla were located in the middle of the subcutaneous adipose tissue. The dermal papillae were separated from the capsule of the secondary hair germ by a cord of follicular keratinocytes. Proximal to the dermal papillae, elements of the connective tissue sac were visible. On the 28th day, corresponding to the telogen stage, the hair follicles were located completely in the dermis, had a rounded, dense dermal papilla, which was adjacent to the germinal capsule. On the 19th and 28th days after anagen induction, a decrease in the width of the dermis and subcutaneous fat was noted.Conclusions. Thus, during the cycle of the hair follicle, its stage-by-stage remodeling and the change in the thickness of the dermis and subcutaneous fat, dependent on this process, take place. The following time sequence of the structural and functional reorganization of hair follicles was determined: on the 1st day after depilation, the hair follicles were synchronized in the anagen I stage, on the 5th day – anagen IIIb, on the 9th and 15th days – anagen VI, on Day 19 – catagen VI stage, on day 28 – telogen stage.
Goal. To study and analyze the relationship of autoimmune diseases of the skin to sex and age. Materials and methods. Study of the relationship of autoimmune of skin diseases to sex and age was performed using contingency table analysis methods, which included the implementation of Pearson x2 to test the hypothesis of independence of the two nominal attributes, calculation of standardized residual values, mapping the relevant category attributes using the method of correspondence analysis, calculation of coefficients of communication Pearson, Chuprova and Kramer. Differences were recognized to be statistically significant at the observed level of significance p < 0,05. In the analysis of standardized residuals were established the following conditions: if the absolute value of the standardized residuals ≥ 2, it was considered that the differences between the observed and expected frequencies are statistically significant at the 0,05 level, if standardized residue ≥ 2,6 the differences are significant at 0,01, if the residue standardized ≥ 3,3 the differences are significant at the 0,001 level. Results. Autoimmune skin diseases linked to sex and age of patients. Vitiligo is associated with male sex, localized scleroderma with women. Sex as a biological factor does not affect the appearance of alopecia areata, lupus erythematosus and bullous dermatosis. Age has in general a greater influence on the formation of autoimmune dermatoses. Alopecia areata is associated in the age period 0-14 and 30-44 years, vitiligo with age period 18-29 years, bullous dermatosis linked to the age group 60 years and older. Conclusion. Sex and age have a differential impact on the formation of autoimmune dermatoses, as biological risk factors of their formation.
In the model experiment on C57BL /6 mice there were established features of the impact of heavy metals and chelators of essential metals on proliferation and apoptosis of epithelial skin cells (keratinocytes). For the execution of a study 40 test animals were divided into seven experimental and 1 control groups, each consisted of five animals. The proliferative and apoptotic activity of keratinocytes was determined by the immunohistochemical method and evaluated by calculating the proliferation index and the index of apoptosis in the cells of the surface epithelium and the epithelial cells of hair follicles in the late anagen stage. Comparative analysis of the proliferation index of the control group and experimental groups showed administration of zinc sulfate, sodium dichromate and zinc chelator (N, N, N`, N`-tetrakis (2-pyridylmethyl) ethylenediamine) to animals to give rise in a statistically significant increase in the proliferative activity of keratinocytes. The decline of proliferation index was detected in animals treated with lead acetate and copper chelator (ammonium tetrathiomolybdate). Introduction of an iron chelator (deferoxamine) had no effect on the proliferative activity of keratinocytes in experimental animals. Induction of apoptosis of epithelial cell was noted under the administration of nickel sulfate, sodium dichromate, lead acetate and zinc chelator (N, N, N`, N`-tetrakis (2-pyridylmethyl) ethylenediamine) to animals. In mice received deferoxamine zinc sulfate and apoptotic activity of keratinocytes has not changed. The use of cluster analysis allowed to classify substances administered to experimental animals, taking into account their simultaneous effect on the studied cellular processes. Lead acetate, iron chelator (deferoxamine) and copper chelator (ammonium tetrathiomolybdate) were shown to reduce the proliferative activity of keratinocytes and have little effect on apoptosis of the epithelial cells of the skin. Zinc sulfate, nickel sulfate, sodium dichromate and zinc chelator (N, N, N`, N`-tetrakis (2-pyridylmethyl) ethylenediamine) activate cell proliferation and induce apoptosis of keratinocytes.
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