Histomorphological changes in the rat pancreas after methionine administration

The effectiveness of using various methionine preparations for activating pancreatic function is ambiguous; the reasons may include differences in dosage and duration of methionine administration. The question remains, in what extent the methionine application is efficacious for increasing functional activity of a healthy pancreas. The aim of our study was to investigate morphological changes in pancreas after prolonged administration of methionine. The experiments were carried out on 24 males of Wistar rats at the age of 15 months. During 21 days, the experimental animals received methionine at a daily dose of 250 mg/kg of body weight in addition to the standard diet. Histological preparations were made from pancreatic tissue according to standard method. Morphometry was performed using the computer program «Image J». The rats were taken out of the experiment under ether anesthesia. The studies were carried out in accordance with the provisions of the "European Convention for the Protection of Vertebrate Animals used for Experimental and Other Scientific Purposes" (Strasbourg, 1986). Upon completion of the experiment, histomorphological sings of an increase in functional activity were registered in both exocrine (enlarged acini’s areas and their epithelium height, higher nuclear-cytoplasmic ratio of exocrinocytes, and higher number of nucleoli in cell nuclei) and endocrine (enlarged sizes of the Langerhans islets and increased number of endocrinocytes in the islets) parts of the rat pancreas. In the experimental rats, the relative area of ​​the connective tissue and the stromal-parenchyma index of the pancreas, as well as the width of the interlobular and interacinus layers of connective tissue decreased. A decrease in the mass of connective tissue in the pancreas can be considered as one of the signs of its function activation, an improvement in metabolism between acini, and an increase in regenerative capabilities. Thus, additional administration of prophylactic doses of methionine to healthy animals results in distinct morphological signs of increased pancreatic activity.

Analysis of Drosophila melanogaster reproduction and preadult mortality after the influence of microwave radiation

A new type of anthropogenic impact – low-intensity electromagnetic radiation of extremely high frequencies (EHF EMR) demonstrates various genetic effects. The questions of the organism adaptive response formation to short-term exposure of EMR that depends on the individual’s genotype are of particular interest. The objective of this study was to analyze the reproductive ability and preadult mortality in Drosophila melanogaster with whiteapticot mutation after the influence of microwave radiation. We used D. melanogaster stocks that carry whiteapticot mutation, but differ in the genetic background on which this mutation is located: wa(C-S), wa(Or) and wa. Virgin flies were irradiated. The parameters of the external influence were power flux density W=10 μW/cm2, frequency F=65 GHz, exposure time t=5 minutes. The stages of embryo death, number of adult offspring, and mortality rate at the pupal stage were analyzed. The results of the study showed that the effect of electromagnetic radiation on virgin imagoes of Drosophila with an impaired tryptophan metabolism modifies the survival rate of the offspring at the preimaginal stages of ontogenesis. In the offspring of young flies (at the age of 3–8 days) the frequency of embryonic mortality decreases during the 0–5.5 hours period (initial stages of cleavage and blastoderm formation) and 5.5–17 hours period (stage of gastrulation and embryo segmentation, histogenesis) of embryogenesis. The total number of offspring at the adult stage does not differ from the control values; the mortality rate at the pupal stage also does not change in the offspring of young parents after exposure to EMR. An increase in the age of parental couples that were exposed to short-term EMR on the first day after eclosion from pupae (20–25 days aged) leads to a decrease in the embryonic mortality rate of offspring during the 17–22 hours of embryogenesis (organogenesis stage and larval exit from chorion). The total embryonic mortality rate is determined solely by the age of the parents. The strength of this factor for the stocks is h2wa=69.7 %, h2wa(C-S)=52.2 % and h2wa(Or)=64.9 % respectively. The impact of EMR affects the embryonic mortality rate only for the wa(Or) (h2EMR=18.3 %). External exposure does not change the number of imago offspring in individuals aged 0–5 days; the number of adult offspring increased by 1,2 times in individuals aged 20–25 days in the stock wa(C-S). A decrease in the number of dead individuals at the pupal stage in the descendants of 20–25-day-old parents after exposure to EMR EHF on average by three times was shown.

Forms and ultrastructural features of the lateral alae of the helminth Trichostrongylus tenuis Mehlis, 1846 (Nematoda: Trichostrongylidae)

Ultrastructural features of the nematode Trichostrongylus tenuis were studied. Helminthological studies were carried out in the Nakhchivan Autonomous Republic in 2015–2018. The material from domestic waterfowl was collected by the method of complete parasitological dissection. Along with the fact that this helminth is a specific parasite of domestic waterfowl, it dominates among all the types of helminths noted by us and is the cause of serious changes in the host organism. The study of the ultrastructure of the nematode T. tenuis is important for identifying parasitic-host relationships, clarifying the systematic position of parasites and in preparing measures to combat these parasites. In addition, a wide variety of morphological features of the lateral alae, allows them to be used as one of the main features for identifying helminth species. The article first presents data on the ultrastructural features of the lateral alae of the nematode T. tenuis. As a result of the studies, it was found that, despite the fact that in some parasitic nematodes of the Trichostrongylidae family the morphological structure of the lateral alae of the cuticle is identical over the entire surface of the body, in the nematode T. tenuis belonging to the same family, four forms were revealed during ultrastructural studies, which were represented using diagrams and electron diffraction patterns. Lateral alae consist of cortical, homogeneous, and fibrillary layers differing in size, thickness, and other features. From the front (oral) part of body of the nematode T. tenuis to the beginning of the intestine, the cuticle is smooth; on the body part from the small intestine and behind it, lateral alae begin to be observed, which resemble a “ridge” in shape. When approaching the posterior end of the body, the lateral alae take the form of “hooks”. On the caudal region, the lateral alae become even more complicated and get the form of “spikes”, and relatively small outgrowths are additionally observed on these lateral wings. These signs can be used to clarify the taxonomic position of helminth species.

Dirhenium(III) complex with beta-alanine ligand: anticancer, antioxidant and DNA-binding properties

Earlier we have shown that dirhenium(III) dicarboxylate complex with γ-aminobutyric acid possessed higher antitumor activity, than those of the previously investigated alkylcarboxylates, also may act as a modulator of cisplatin mechanism of action and as a stabilizer of red blood cells in tumor-bearing organisms. Thus, the task of the work was to investigate anticancer activity of the complex cis-[Re2(β-Ala)2Cl6] (I) in the model of tumor growth in vivo and to realize if the amino acid residue influences the DNA-binding activity of the amino acid derivatives of the cluster rhenium(III) compounds. Antitumor properties of the complex I were studied in the model of tumor growth with the use of Wistar rats inoculated by tumor carcinoma Guerink cells. The introduction of the compound alone in free and liposomal forms inhibited the tumor growth by 36 % and 45 % correspondingly, that is more than for dirhenium(III) clusters with alkyl ligands. The combined introduction of I and cisplatin had a significant impact on the tumor growth and showed the disappearance of the tumors in most of the animals. No considerable differences were found between introduction of liposomal and free form of I. The electronic absorption spectra of Calf Thymus DNA (CT-DNA) exhibit hyperchromism in the presence of increasing amounts of I. The DNA band at ~ 260 nm arises from the π-π* transitions of the nucleic acid bases and changes in the intensity and slight wavelength shifts of this characteristic band reflect the corresponding structural modifications of the DNA, which include changes in stacking, disruption of the hydrogen bonds between complementary strands, covalent binding of the DNA bases, intercalation of aromatic rings and others. The binding constant Kb(I) = 2.43 × 103 M-1 to CT-DNA was obtained that was lower than the values reported for the classical DNA intercalators and compares well with the magnitude of the binding constants for other complexes of dirhenium(III); titration of СT-DNA with cisPt and hydrogen peroxide also leads to a hypochromic effect, weak at low concentrations and more significant at high concentrations of I; the DNA binding constants increased in several times when using H2O2 or cisplatin that confirms a mechanism for redox activation of interaction of I with DNA in a cancer cell. The obtained results demonstrate the possibility of application of the amino acid derivatives of dirhenium(III) clusters in antitumor therapy.

The reaction of self-fertile alfalfa lines to inoculation with nodule bacteria

Under the conditions of a model pot experiments, the reaction of the self-fertile lines of alfalfa Kishvardy 46, Kishvardy 27, Vertus and Ziguen to inoculation with nodule bacteria Sinorhizobium meliloti AC48 and AC88 was studied. As a result of studies, it was found that the intensity of assimilation of N2 by symbiotic systems created with the participation of various genotypes of alfalfa and active strains of S. meliloti is one of the main factors that affects the vegetative mass yield of this important forage crop. Self-fertile lines of Medicago sativa L. plants, inoculated with different strains of rhizobia were characterized by higher rates of the mass formed on the root nodules, compared to the control plants of the alfalfa variety Yaroslavna. The traditional dynamics of nitrogen-fixation activity of root nodules was maintained in all the symbiotic systems studied by us, with low values in the stems formation stage and intensive growth in the budding and flowering stages. The highest level of nitrogen fixation and vegetative growth of plants (values of plants green and dry mass, roots and root nodules mass) was established by inoculation of alfalfa line Kishvardy 46 with strain S. meliloti AC48. During the growing season the indices of the mass of nodules formed on the roots of these plants were higher by 1.8–2.3 times, the green mass by 1.2–1.6 times and the height of the plants 1.2–1.4 times as compared to the control. In the flowering stages the nitrogen-fixation activity of the symbiotic complex of plants of the Kishvardy line 27 and nodule bacteria S. meliloti AC48 exceeded the values in the symbiotic systems formed with the participation of the same strain and plants of the Ziguen and Vertus lines by 13.0 and 39.4 %. The lowest values of nitrogen fixation activity were observed by inoculation of plants of the Vertus and Ziguen lines with active strains S. meliloti AC48 and AC88 compared to the symbioses formed by the plants of the Kishvardy lines 27 and 46, as well as of the control-variety Yaroslavna with the noted strains. A stimulating effect of inoculation of alfalfa seeds of different genotypes on the growth and development of plants was noted, as evidenced by the positive dynamics of the increase in above-ground mass, the accumulation of dry matter and higher than the control values (indicators) of plant height during the growing season.

Mites of the genus Erythraeus Latreille, 1806 (Acariformes: Actinedida: Erythraeidae) in the Greater Caucasus (within Azerbaijan)

Mites of the family Erythraeidae Robineau-Desvoidy, 1828 are distributed worldwide and have been reported as natural enemies of sucking pests. Adults and deutonymphs are predators; larvae of most species are ectoparasites of different arthropods. They can be harmful to beekeeping. Some species cause dermatitis in humans. Erythraeidae of the Caucasus are poorly studied. This article is the first report on mites of the genus Erythraeus Latreille, 1806 of the family Erythraeidae living in Azerbaijan. An annotated list of five species of mites of this genus collected in the Greater Caucasus is provided: Erythraeus phalangoides (De Geer, 1778), E. regalis (C.L.Koch, 1837), E. gorcensis Gabrys, 2016, E. opilionoides (C.L.Koch, 1837), E. adpendiculatus (Schrank, 1781). All of them are recorded from Azerbaijan for the first time. An identification key to imago of the Erythraeus species is given. The original photographs of imago were taken to clarify the determination. Mites were collected in three landscape zones: semi-desert (4 species), mountain-steppe (2 species) and mountain-forest (2 species). The Absheron Peninsula (semi-desert) is studied best; four Erythraeus species were found there. Most of the species were collected in artificial forests with a predominance of Eldar pine (4 species, 12 individuals). In other biotopes, mites of the genus Erythraeus are rare: 2 species (3 individuals) were found in broad-leaved forests of the low mountains, 1 species (1 individual) in a forb steppe, 1 species (1 individual) in an arid open woodland consisted of weeping pear trees, 1 species (1 individual) in a garden. Only four individuals of E. regalis were recorded on plants. The other mites were collected under stones, which will make it possible to attribute them to herpetobionts, and E. regalis to herpeto-hortobionts. Out of 18 individuals found, 17 were adult, and one larva of E. regalis was removed from spittlebug on a blackberry. The most common Erythraeidae genus in the Greater Caucasus is Abrolophus Berlese, 1891 (39 individuals belonging to eight species were collected). This is the only genus of the family Erythraeidae, found in four landscape zones, from semi-desert to subalpine. The genus Erythraeus was not found in the subalpine zone.

Formation and self-maintenance of the population Hyssopus officinalis L. in conditions of the iron ore dump of Krуvyі Rih area

We ascertained the features of formation of self-renewing and self-sustaining of the local population of the Mediterranean introducent Hyssopus officinalis L. in the extremal ecologic and edaphic conditions of an iron ore dump in Kryvyi Rih Area, seeds of which have been sown on the area of 1 ha about 30 years ago. It was found that the species, during this period after reaching the reproductive phase of development, has taken the area of the dump of about 3 ha and, in fact, it formed the isolated population. This species annually multiplied by seed, and spread on the areas of ore dump, where almost no vegetation cover, in fact, performing a pioneer function. At the site, where the initial sowing of H. officinalis seeds was carried out, the phytocoenosis forms now; this phytocoenosis, according to its floristic composition, approaches the natural steppe, but the introduced species are gradually ousted. In habitats occupied by the species due to its spontaneous distribution, successional processes are at an initial stage. Within some of the population loci of H. officinalis, we have found up to 513 adult individuals with the number of generative sprouts from 20 to 70 per a plant. Flowers are formed on these sprouts in average from 160.2 to 181.6. Average seed productivity is 60 % of theoretically possible rate, and the seeds from the parent species extend to a distance of 1–5 m. In a compact areas where H. officinalis grows, there are plants of all the age groups – from the seedlings to the subsenile. H. officinalis has naturalized in the dump conditions, and its local population is а resistant, full-grouped; it develops under the conditions where other species are not competitive. Generatively developed plants are higher than 90 cm and have good vital state. The species on the dump shows pioneering features; it is not aggressive and can be displaced by zonal vegetation; thus, it does not pose invasion risk. H. officinalis can be recommended for the revegetation of iron ore dumps, or their large decommissioned areas, without technical preconditioning, only by direct sowing of the seeds into the dump rocks, to promote its spread artificially.

Influence of phosphorus compounds on the formation of ammonium ions by cells of nitrogen-fixing bacteria Аzotobacter chroococcum VKM V-1272

This article presents the results of investigation of the influence of inorganic compounds of phosphorus (potassium hydroortophosphate, sodium hydroorthophosphate) and phosphorus fertilizers (superphosphate, phosphorite flour) on the accumulation of biomass and the formation of ammonium ions by the cells of nitrogen-fixing bacteria А. chroococcum VKM V-1272. Sodium hydrophosphate, superphosphate and phosphorite flour were introduced into the culture medium (Ashby medium) instead of K2HPO4 at equimolar concentrations to the phosphate ion concentration in Ashby medium and at double concentration. It was established that Na2HPO4·12H2O, superphosphate and phosphorite flour at equimolar concentration stimulated the accumulation of biomass of A. chroococcum VKM V-1272, but at higher concentration they inhibited bacterial growth when compared to control. An increase of the concentration of Na2HPO4·12H2O and K2HPO4 in the culture medium there was inhibited not only the growth but also the formation of ammonium ions by A. chroococcum VKM V-1272 bacteria. Phosphate fertilizers at all concentrations inhibited the nitrogen fixation process. The effectiveness of the using of phosphorus compounds by bacteria А. chroococcum VKM V-1272 in the growth process has also been investigated. It has been established that soluble inorganic compounds (potassium hydroortophosphate, sodium hydroortophosphate) can be used by bacteria with different effectiveness as a source of phosphorus. In a medium with Na2НРО4·12H2O, К2НРО4 and superphosphate we observed a decrease of the concentration of phosphate ions that evidences that bacteria A. chroococcum VKM B-1272 use them during growth. Increasing of the concentration of phosphate ions in the medium with phosphorite flour indicates the ability of bacteria to phosphate mobilization. So the accumulation of biomass and the formation of ammonium ions by nitrogen-fixing bacteria A. chroococcum VKM B-1272 depended on the nature and concentration of the phosphorus source in the growth medium. Therefore, further studies of the influence of phosphorus nutrition on the physiological and biochemical properties of nitrogen-fixing bacteria will allow to evaluate the sensitivity of A. chroococcum VKM B-1272 to the action of inorganic pollutants and to show the importance of rational use of phosphorus fertilizers in agriculture.

New records of tardigrade species of the Macrobiotus hufelandi group (Tardigrada: Eutardigrada: Macrobiotidae) from Ukraine

Species of the Macrobiotus hufelandi group are among the most well known and commonly found tardigrades. They are reported in almost every study of Tardigrada diversity in terrestrial habitats. In spite of this, zoogeographical data on this group remain ambiguous and insufficient. Since most species of the M. hufelandi group have been described in the last three decades, many older records need to be confirmed or revised. In this study we aimed to investigate, which species may be present in Ukraine, since most Ukrainian records of this group are outdated. We studied samples of mosses and lichens collected from different regions of Ukraine (mainly in the East and South of the country) in 2007–2019. Tardigrades were extracted from samples and mounted on permanent slides in Faure's medium. After primary identification of genera and species groups we focused on 13 samples containing local populations of the M. hufelandi group. Details of animal and egg morphology were studied under high magnifications of phase contrast light microscopy. Species were identified based on morphology of the oral cavity armature, egg shell morphology, animal cuticle granulation, as well as some morphometric characters of claws and bucco-pharyngeal apparatus. This research revealed the presence of at least six different species in Ukraine: M. glebkai Biserov, 1990; M. hufelandi C.A.S. Schultze, 1834; M. macrocalix Bertolani & Rebecchi, 1993; M. polonicus Pilato, Kaczmarek, Michalczyk & Lisi, 2003; M. sottilei Pilato, Kiosya, Lisi & Sabella, 2012; M. vladimiri Bertolani, Biserov, Rebecchi & Cesari, 2011. Three of them: M. macrocalix, M. sottilei, and M. vladimiri are reported in this study from Ukraine for the first time. Adding three more species recorded in earlier studies: M. diversus Biserov, 1990; M. persimilis Binda & Pilato, 1972, and M. sapiens Binda & Pilato, 1984 – gives the total count of at least 9 species of the group in Ukraine. However, according to the recent studies on species complexes the real species diversity is very likely to be higher. Nevertheless, more sampling and obtaining molecular data from different Ukrainian populations of the M. hufelandi group from Ukraine are required.

Features of floristic structure and productivity of dry meadows of the Left-Bank Forest-Steppe of Ukraine

The article presents the results of study of floristic structure and productivity of the dry meadows preserved in the ravine and gully system in the Zmiiv District of the Kharkiv Region. The research was carried out at the model sites with floral composition and features of use typical for the Left-Bank Forest-Steppe of Ukraine. It was established that the total phytocenosis productivity depends on the phytomass fluctuations of two main groups of plants, forbs and grasses. The flora of the studied meadows includes at least 87 vascular plant species. The ten main families altogether number 70 species (80.5 % of the species composition). The families Asteraceae Bercht. & J. Presl (23 species, 26.4 %), Fabaceae Lindl. (11 species, 12.6 %) and Poaceae Barnhart (8 species, 9.2 %) are presented best. This ratio of families is characteristic of herbaceous phytocenoses of the Holarctic floristic realm. The Poaceae family plays the leading role in the formation of meadow phytocenoses, since its members often dominate the main meadow formations. Analysis of the flora ecomorph spectrum revealed prevalence of a xerophilous group that includes meadow, meadow-steppe and steppe species. The obtained data indicate a rather significant xerophytization of the study area, which is typical for the growing conditions of the dry meadows located on the watersheds with atmospheric type of humidification only. Perennial herbaceous meadow-steppe and some ruderal species prevailed in the life form spectrum (77.0 %), which is characteristic of the meadow flora of the Kharkiv Region. Annual segetal weeds, introduced from neighboring fields, contribute significantly to the meadow flora (17.2 %), in particular, such adventive species as Ambrosia artemisifolia L., Amaranthus retroflexus L., and Cyclachaen axanthifolia (Nutt.) Fresen. The research of phytocenose productivity showed that the Poaceae proportion in the meadows with high productivity is usually about 35‒40 %. In the meadows with low productivity, it can exceed 50 % that is explained by the leading role of the family Poaceae in the formation of meadow phytocenoses under high xerophytization of the vegetation cover.