Seasonal features of leptospirosis clinical course in Lviv Oblast, Ukraine are decribed in this abstract.

This research was presented on the 2023 Annual Meeting of American Society of Tropical Medicine and Hygiene (18-22 October, 2023, USA)

Leptospirosis is a bacterial disease that affects both humans and animals worldwide. Clinical symptoms of leptospirosis in humans range widely, from mild to severe illness, with symptoms that can include severe jaundice, acute renal failure, hemorrhagic pneumonia, and meningitis. We present a detailed clinical description of a 70-year-old man with leptospirosis. This case presented without the typical prodromal period for leptospirosis, thus making diagnosis more difficult. This isolated case occurred in the Lviv region during the ongoing military conflict between Russia and Ukraine where Ukrainian citizens have been forced to hide in premises that are not properly adapted for their long-term stay, which result in conditions that can potentially lead to the emergence of many infectious diseases. This case highlights the need for heightened awareness into the symptoms of a variety of infectious diseases, including but not limited to leptospirosis.

 The immune system plays a crucial role in maintaining the body's homeostasis, determining the state of health of animals and their ability to adapt. The work aimed to investigate the effect of a feed additive based on milk thistle fruits, selenium, metiphene, and vitamins A, E, and C on rats' immune status under experimental tetrachloromethane poisoning conditions. The study was conducted on young white male Wistar laboratory rats. Intragastric administration of tetrachloromethane twice (with an interval of 48 hours) in a dose of 0.1 ml per 100 g of body weight in a 50 % oil solution was used for the experimental intoxication of rats. The animals of the second experimental group were fed the feed additive “Sylimevit” for 30 days together with feed at a dose of 0.1 g per 100 g of body weight. The introduction of tetrachloromethane in experimental groups of rats led to the development of oxidative stress, which occurs due to specific chemical processes in the body of experimental animals. It was found that the development of oxidative stress caused by tetrachloromethane leads to suppression of the humoral and nonspecific link of the immune system of rats. This is manifested in a decrease in the bactericidal and lysozyme activity of the blood serum, a decrease in the phagocytic index, and the phagocytic activity of neutrophils. In addition, an increase in the number of circulating immune complexes was observed. It was also established that feeding the feed additive “Sylimevit” strengthens the immune defense of the body of rats poisoned with tetrachloromethane. This feed additive helps to strengthen the body's defense mechanisms, increasing
the immune response and helping to resist the toxic effects of tetrachloromethane.

Introduction. The doxorubicin model was used for research, which, according to many authors, most adequately reproduces heart failure of varying degrees of severity. Doxorubicin is an antibiotic that has a cytostatic effect. The mechanism of its action consists of interaction with DNA, formation of free radicals, and inhibition of nucleic acid synthesis. The doxorubicin action and the development of hypoxia are accompanied by the activation of oxidative stress, the strengthening of free radical processes, and changes in the metabolism of carbohydrates, proteins, and lipids.
The aim of the study – the effect of the drug “Bendamine” on the indicators of antioxidant protection of the body of rats under experimental simulation of heart failure.
Research Methods. Modeling of heart failure was performed on sexually mature male Wistar rats with a body weight of 180–200 g. In blood and myocardial homogenate, the level of lipid peroxidation products, the activity of antioxidant enzymes, and the level of reduced glutathione were determined against the background of doxorubicin intoxication and when using the drug “Bendamine”.
Results and Discussion. During doxorubicin intoxication, LPO processes are enhanced in rats, which is indicated by the increased lipid hydroperoxides, diene conjugates, and TBA-active products in the blood and the homogenate of the rat myocardium of the first experimental group. It is worth noting that the inhibition of the antioxidant defense system was also established in intoxicated rats, as indicated by the low level of both enzymatic and nonenzymatic links of the antioxidant system. It was established that bendamine has a corrective effect on rats' oxidative stress conditions inherent in doxorubicin-induced heart failure. The drug “Bendamine” inhibits the excessive formation of POL products in pathologically changed tissues of the heart of rats and has an inducing effect on the system of antioxidant protection.
Conclusions. The influence of the drug "Bendamine" on the indicators of antioxidant protection of the body of rats under experimental simulation of heart failure was studied. Its antioxidant properties have been proven.

The properties of the spin-valve structure, based on two ferromagnetic layers divided by a layer of non-magnetic metal, in the geometry of the current perpendicular to the plane are modeled. In addition to well-known classical twochannel conductivity model proposed by Nevill Mott, the developed model takes into account spin scattering on the surface between structures. The developed model uses equivalent electrical circuits to simulate a spin valve with parallel and antiparallel alignment. On the basis of this model, the dependences of the giant magnetic resistance on two geometric parameters of the structure—the ratio between the thickness of the free and the thickness of the fixed layers, and their ratio to the length of spin diffusion—are derived. Based on the developed model, numerical data are obtained for the spin valve, where the ferromagnetic layers are made of cobalt, permalloy, iron, and nickel. The portion of surface scattering in the giant magnetic resistance is also investigated. A general conclusion is made about the slight increase of the giant magnetic resistance due to the influence of surface scattering for structures based on cobalt, permalloy, and iron, but not for nickel. This outlines the scope of applicability of the developed model.