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An investigation was conducted on the effect of sodium chloride concentration on corrosion inhibition efficiency of High-Density Polyethylene (HDP) coating on alloy steel in sodium chloride solutions of different degrees of salinity. In the study, four test media were used: the first is 20 l of distilled water in a rectangular base plastic container; the second is 20 l of distilled water in a rectangular base plastic container in which 200 g of sodium chloride (NaCl) was dissolved entirely, giving a concentration of 10 g/l (0.01 g/cm²). Similarly, the third medium is 20litres of distilled water in which 300 g of NaCl was dissolved entirely, having 15 g/l (0.015 g/cm²) concentration. The fourth medium is prepared by dissolving 400 g of NaCl in 20litres of distilled water, resulting in 20 g/l (0.02 g/cm²) concentration. The container used for each medium is a rectangular base plastic container. Twenty-eight (28) uncoated and twenty-eight (28) polyethylene-coated alloy steel coupons of dimension 5×30×50 mm with an 8 mm diameter hole each were used for this investigation. Seven coated coupons each were wholly immersed in 10, 15, and 20 g/l, and zero salinity distilled water. Similarly, seven uncoated coupons each were immersed entirely in 10, 15, and 20 g/l and zero salinity distilled water. The coupons in various test media were exposed to ambient temperature for a total of 49 days. One coupon from each of the media is reweighed on weekly bases and the weight loss (g), corrosion rate (mm/year), and corrosion inhibition efficiency were calculated and recorded. From the results obtained, the corrosion rate of the coupons increases with an increase in sodium chloride solution. It is also observed from the results obtained considering the variation of corrosion rates of polyethylene coated coupons with sodium chloride concentration and the variation of corrosion rates of uncoated coupons with sodium chloride concentration that the corrosion rate of the coupons is lesser with the polyethylene coating compared with the uncoated coupons. The results show that the corrosion rate of coupons falls over time, and more rapidly at an early time of exposure, say the first week. From the result of the variation of corrosion inhibition efficiencies of polyethylene coated coupons with sodium chloride concentration, it is observed that the corrosion inhibition efficiency of polyethylene decreases over time and decrease also with an increase in sodium chloride concentration.

It was investigeted 126 patients with chronic atrophic gastritis, aged 19-73 years. Chronic inflammatory and degenerative processes of the gastric mucosa contributed to the destabilization of cell membranes. We found that patients with chronicatrophic gastritis have disturbances of lipid peroxidation and antioxidant defense, which is manifested by the accumulation of products of peroxidation and decreased activity of enzymes of antioxidant defense. Activation of lipid peroxidation, accompanied by increased levels of proinflammatory cytokines and deficiency of essential trace elements imbalance contributes antioxidant defense. After using basic therapy, it was no certain normalization of lipid peroxidation, antioxidant defense and restoration of microelement homeostasis in patients with chronic atrophic gastritis, which served as the justification for the development and testing of methods of treatment with the purpose of regulation of these processes.

Morphology was studied together with the condition of the local cell-bound immunity in 24 patients who were not exposed to occupational hazards in their occupations and in 32 miners with a long length of service. The above subjects underwent esophagogastroduodenoscopy involving taking of gastrobiopsy specimens. In miners there prevailed chronic atrophic gastritis. Immune mechanisms are involved in its pathogenesis, which fact is evidenced by the lymphoid-and-plasmocellular infiltration of the mucous membrane with a plentiful concentration of plasmatic cells and formation of lymphoid folliculi. They run their course against the background of an apparent lowering of local cellular defence, which event determines progression of chronic atrophic gastritis.

It was found that rheumatoid arthritis patients with clinical signs of cardiac involvement showed significant changes of the central and intracardiac hemodynamics that were characterized by suppression of the contractile and pumping function of the left ventricle as compared with patients showing no heart involvement. The authors describe in detail special treatment of RA patients with cardiac involvement.