The Reference Values of Hair Content of Trace Elements in Dairy Cows of Holstein Breed.

The objective of this study was to assess trace element content in hair of Holstein dairy cows bred in the Leningrad Region of Russia and to calculate the site-specific reference intervals. Hair content of arsenic, boron, cadmium, cobalt, chromium, copper, iron, mercury, iodine, lithium, manganese, lead, selenium, silicon, tin, strontium, vanadium, and zinc in 148 cows during first (n = 50), second (n = 48), and third (n = 50) lactation periods of life was determined using inductively coupled plasma mass spectrometry. Dietary intake of trace elements corresponded to the adequate values according to national and international recommendations. Comparative analysis did not reveal any significant differences in hair content of main essential elements on the animals depending on the number of lactation. At the same time, the first-lactation cows had significantly (P < 0.05) lower concentration of lead in hair as compared to the third-lactation cows and a higher level of mercury as compared to the second-lactation cows. The reference intervals and 90% confidence intervals for the lower and upper limits were calculated in agreement with the American Society for Veterinary Clinical Pathology Quality Assurance and Laboratory Standard Guidelines.

[Comparative Sensitivity of the Luminescent Photobacterium phosphoreum, Escherichia coli, and Bacillus subtilis Strains to Toxic Effects of Carbon-Based Nanomaterials and Metal Nanoparticles].

A comparative analysis of the four commercially available and laboratory luminescent sensor strains to the toxic effect of 10 carbon-based nanomatherials (CBNs) and 10 metal nanoparticles (MNPs) was carried out in this study. The bioluminescence inhibition assays with marine Photobacterium phosphoreum and recombinant Escherichia coli strains were varied in minimal toxic concentrations and EC50 values but led to well correlated biotoxicity evaluation for the most active compounds were ranked as Cu > (MgO, CuO) > (fullerenol, graphene oxide). The novel sensor strain Bacillus subtilis EG 168-1 exhibited the highest sensitivity to CBNs and MNPs that increased significantly number of toxic compounds causing the bacterial bioluminescence inhibition effect.

[MORPHO-FUNCTIONAL CHARACTERISTIC OF THE THYROID GLAND AFTER ADMINISTRATION OF COPPER NANOPARTICLES].

The study was conducted on 15 male Wistar rats, which were injected intramuscularly with copper nanoparticle lyosols at a dose of 2.0 mg/kg body weight once a week for 3 months. Thyroid gland was removed 7 days after the last injection and was studied using histological, morphometric and immunohistochemical methods (demonstration of Ki-67 and caspase-3). Animals of the control group (n = 15) were administered distilled water at the same time intervals. It was found that after 1, 2, 3 and 4 injections of copper nanoparticles, the thyroid gland contained an increased number of large cyst-like follicles, while the average thyrocyte height of and the volume of their nuclei were reduced, which indicate a decline in hormone production. After 12 injections of copper nanoparticles, the hyperplastic thyroid gland demonstrated small follicles lined with columnar epithelium, which contained no or small amount of the colloid. The number of mitotically dividing thyrocytes was increased. Parafollicular cells demonstrated an apoptotic dominant. Morphological data suggest goitrogenic effect of multiple doses of copper nanopartides. The data received indicating the readiness of the thyroid cells to the programmed death and its possible depression (absence of signs of thyrocyte apoptosis) at different stages of the experiment confirm the modulating effect of copper on apoptosis.

[Effect of thrombodefensins on the course of chronic staphylococci dermatitis on in vivo model].

AIM: Evaluate therapeutic effect of thrombodefensins (TD) on the course of chronic staphylococci dermatitis (CSD) in mice. MATERIALS AND METHODS: TD was obtained from human thrombocytes. 24 CBRB-Rb(8.17)1Iem line female mice were used in the experiment, that were divided into 2 equal groups. Staphylococcus aureus strain producing exfoliative exotoxin was isolated from withers of each mouse with signs of affection. Mice of the experiment group subcutaneously around the locus of affection, received for 4 weeks daily a composition in the volume of 0.2 ml, that contains 1 g of dry lyophilized TD diluted in 10 ml of 0.9% NaCl (final concentration of the preparation--15 µg/ml). Control group animals similarly received 0.9% solution of NaCl without TD. Area and degree of the affected zone on the back was evaluated in all the mice. Statistical significance of differences in the values of parameters was determined by t-criteria. RESULTS: At the start of the experiment the average area of the affected zone in mice of both groups was 167 ± 17 mm2. From day 8 to 23 the expansion of the affection zone was observed, however in the experiment group of mice these negative tendencies were less pronounced. At the end of the experiment on day 50 the area of affection was significantly smaller (2.3 times) in the experiment group of mice compared with the control (p < 0.05). CONCLUSION: The anti-staphylococci effect of TD, demonstrated in the study, opens perspective of their clinical use in CSD therapy.

[Copper nanoparticles as modulators of apoptosis and structural changes in some organs].

The effect of repeated intramuscular injection into the organism of copper nanoparticles (CNP) with the diameter of 103 nm on the index of cell readiness to apoptosis and the structure of liver, spleen, kidney, as well as sensomotor cerebral cortex, was studied in 78 male Wistar rats. CNP were injected once per week for 12 weeks. The organs were studied using histological, immunohistochemical and morphometric methods. It was found that after the injections, CNP were distributed into organs and tissues of animals causing structural changes that were specific for eaach tissue. Toxicity of CNP in respect to microgliocytes was demonstrated at a dose of 2 mg/kg, hepatotoxicity and nephrotoxicity--at 6 mg/kg. The increase of CNP load on the organism up to toxic threshold (maximum tolerated dose) resulted in the appearance of signs of dystrophy and tissue necrosis. The data obtained suggest the application of an index of cell readiness to apoptosis, as assessed by caspase 3 expression, as a criterion for evaluation of CNP injection safety.

[Selenium content in meat and poultry in Orenburg region].

Selenium content in beef, pork and poultry from Orenburg Region has been investigated. Regions with low (beef < 112 mcg/kg, pork--about 200 mcg/kg, poultry < 127 mcg/kg), medium and high (beef > 300 mcg/kg; pork--about 600 mcg/kg; poultry--170-180 mcg/kg) selenium levels are indicated. Positive correlations between selenium content in meat and soil are demonstrated (beef/soil +0.558, p < 0.001; pork/soil +0.557, p < 0.001; poultry/soil +0.389, p < 0.05). Meat contribution to selenium consumption is equal to: beef--4.6%, pork--6%, poultry--2.6%.

[Selenium content in bread of Orenburg region].

Selenium content in wheat and rye bread from 35 districts of Orenburg region has been estimated. The results indicate heterogeneity of selenium distribution and the existence of decreased selenium levels in the West of the region. Different factors affecting selenium accumulation by cereals are discussed: heavy metals pollution, Ni and Cu mining, soil salinization.