Effect of water deficit on maize seeds (Zea mays L.) during germination

Received: October 29th, 2022 ; Accepted: March 23rd, 2023 ; Published: April 14th, 2023 ; Correspondence: [email protected] climate changes cause the frequent recurrence of droughts, which reduce crop production more than any other environmental factor. This study was conducted to access the effect of water deficit on maize seeds (Zea mays L.) DKC 5143 hybrid during germination. The tasks were to assess the influence of different rank of osmotic stress on the maize lipid peroxidation (LPO), proline content, catalase and aminotransferases activities, and morphometric parameters during the early stages of maize seeds germination. The maize seeds were exposed to five levels of water availability which produced by PEG-1500 solutions (0, 20, 50, 100, 200 g L-1 ). Seeds of maize were germinated on Petri dishes for 7 days under controlled parameters. Amounts of TBARS were increased in maize sprouted seeds by 1.9 times, coleoptiles by 1.4 times, and in roots - by 1.9 times under water deficit. Proline content increased by 9.2 times in coleoptiles and by 6.0 times in 7 days maize roots while PEG-1500 (200 g L–1 ) treatment. An increasing of catalase (CAT), aminotransferases (ALT, AST) activities according to osmotic potential value was also observed. A remarkable development of maize oxidative reaction was associated with a significant reduction in emergence, wet weight and length of water-stressed plants. These results assume that the maize adaptive strategy to osmotic stress during germination was found in the activation of LPO and antioxidant components. The findings provide useful help for correcting the stress state of maize using osmotically active regulators

Replication timing in Drosophila and its peculiarities in polytene chromosomes

Drosophila melanogaster is one of the popular model organisms in DNA replication studies. Since the 1960s, DNA replication of polytene chromosomes has been extensively studied by cytological methods. In the recent two decades, the progress in our understanding of DNA replication was associated with new techniques. Use of fluorescent dyes increased the resolution of cytological methods significantly. High-throughput methods allowed analysis of DNA replication on a genome scale, as well as its correlation with chromatin structure and gene activi ty. Precise mapping of the cytological structures of polytene chromosomes to the genome assembly allowed comparison of replication between polytene chromosomes and chromosomes of diploid cells. New features of replication characteristic for D. melanogaster were described for both diploid and polytene chromosomes. Comparison of genomic replication profiles revealed a significant similarity between Drosophila and other well-studi ed eukaryotic species, such as human. Early replication is often confined to intensely transcribed gene-dense regions characterized by multiple replication initiation sites. Features of DNA replication in Drosophila might be explained by a compact genome. The organization of replication in polytene chromosomes has much in common with the organization of replication in chromosomes in diploid cells. The most important feature of replication in polytene chromosomes is its low rate and the dependence of S-phase duration on many factors: external and internal, local and global. The speed of replication forks in D. melanogaster polytene chromosomes is affected by SUUR and Rif1 proteins. It is not known yet how universal the mechanisms associated with these factors are, but their study is very promising

FREQUENCY OF POLYMORPHISM OF ALA16VAL GENE SOD2 IN SAMPLES OF MONGOLOID AND CAUCASOID POPULATION, LIVING IN EASTERN SIBERIA

The article presents the study of superoxide dismutase 2 gene polymorphism that plays an important role in antioxidant protection of an organism. We performed genetic typing in representatives of two ethnic groups of Eastern Siberia - Buryats (Mongoloid) and Russians (Caucasoid). Alleles frequencies among Russians were Ala = 0,492; Val = 0,508; among Buryats Ala = 0,343; Val = 0,657. We compared these frequencies between the populations from Russia and from abroad (according to the results of other researches)

ETHNO-GENETIC MARKERS OF ANTIOXIDANT SYSTEM (LITERATURE REVIEW)

Oxidative stress plays an important role in the pathogenesis a most of diseases. Important components of protecting cells from oxidative stress are antioxidant enzymes, whose activity is genetically determined, due to the presence in the structure of the alleles of genes. Antioxidant enzymes are characterized by population and individual differences in enzyme activity. The study of genetic variation in the population of the world and the history of the formation of its gene pool is one of the promising areas of modern population genetics. Genetic variability of antioxidant enzymes in the body has recently become the most attractive destination in the pathogenesis of many diseases. Due to the involvement of enzymes in the pathogenesis of antioxidant enzymes social diseases is an important implementation. Comprehensive study of the genetic polymorphisms of genes contributes to the formation of human disease susceptibility. The antioxidant system is of the person a system that blocks the formation of free radicals, highly active oxygen. Under normal physiological conditions, a small amount of oxygen is constantly converted to superoxide anions, hydrogen peroxide and hydroxyl radicals. Excessive production of these radicals is a factor of injury; compensatory mechanism is the antioxidant system. The main component of this system is a network of antioxidant enzymes (AOP): superoxide dismutase (SOD), glutathione peroxidase (GPX), catalase (CAT) and paraoxonase (PON). In this case, the activity of enzymes evolutionarily and genetically programmed to optimize the balance of oxidative processes and the activity of antioxidant defense systems. The purpose of the review is to summarize and discuss the current data on genetic polymorphisms of antioxidant enzymes in certain pathologies, the development of which plays the role of oxidative stress

СТАВЛЕННЯ МАЙБУТНІХ ЛІКАРІВ ДО ЛЮДЕЙ, ЯКІ ЖИВУТЬ З ВІЛ

SUMMARY. Tolerance to HIV-infected students in higher education is a very important aspect of future doctors in overcoming the consequences of the HIV epidemic. Almost half of students (48,8 %) are biased towards HIV-infected, so you need to choose the right strategy for medical education programs.Key words: people living with HIV, attitudes of doctors.Формування толерантного ставлення до ЛЖВ у студентів вищих медичних навчальних закладів є дуже важливим аспектом роботи майбутніх лікарів у подоланні наслідків епідемії ВІЛ. Майже половина студенти (48,8 %) ставляться до ЛЖВ упереджено, тому потрібно обирати правильні стратегії медичних освітніх програм.Ключові слова: люди, які живуть з ВІЛ, ставлення лікарів

ALA16VAL POLYMORPHISM OF SUPEROXIDEDISMUTASE 2 (SOD2) GENE IN CAUCASOID TEENAGERS WITH HYPERTENSION, LIVING IN THE EASTERN SIBERIA

The article presents the analysis of distribution of alleles and genotypes of AIa16VaI polymorphism (rs4880) of superoxidedismutase 2 (SOD2) gene in Caucasoid teenagers with hypertension (n = 102) and in Caucasoid popuIation sampIing (n = 65), Iiving in the Eastern Siberia. Frequencies of aIIeIes in popuIation sampIing were AIa = 0,492 and VaI = 0,508, of genotypes - AIa/AIa = 0,277; AIa/VaI = 0,431 and VaI/VaI = 0,292. In the group of teenagers with arteriaI hypertension the frequency of aIIeIes was AIa = 0,495 and VaI = 0,505, of genotypes - AIa/AIa = 0,245; AIa/VaI = 0,500 and VaI/VaI = 0,255. There were no significant differences found at the comparison the data

THE DEPOSIT OF ANTIBODY’S PROLIFERATIVE ACTIVITY IN THE IMMUNE RESPONSE AND ITS RESISTANCE TO INHIBITORS OF PROLIFERATION

The effect of hyperstimulation of the primary immune response was showed by additional introducing of antigen in the late log-phase of the primary IgM-response. The multiple increase of IgM-and IgG-antibody productive cells (АРС) in the spleen during the primary response was accompanied by suppression of anamnestic response. The injection of hydroxyurea (an inhibitor of DNA synthesis) together with the additional introduction of the antigen at the late log-phase of the primary IgM-response reduces the rise of IgM-APC, but does not abolish the stimulation of the primary and secondary IgG-APC formation. This fact indicates that proliferative processes play an important role in the stimulation of IgM-response induced by reinjection of the antigen. The stimulation of proliferation of B-lymphocytes which differentiate into antibody productive cells significantly reduces the pool of memory cells and consequently, suppresses secondary immune response

EFFECTS OF PSYCHOPHYSIOLOGICAL NEUROTHERAPY IN REGULATION IMMUNE RESPONSE COMBINED WITH STANDARD ANTITUBERCULOSIS DRUG THERAPY IN ACUTE PULMONARY TUBERCULOSIS

The aim of this study was to assess optimizing effects of antistress neurotechnologies on the clinical course of acute pulmonary tuberculosis. The study was performed in three steps: upon admission before treatment, followed by repeated examination at 2 and 4 months. The patients before study were divided into the two groups: (1) 33 patients received standard antituberculosis drug therapy (SDT) and (2) 35 cases after standard antituberculosis drug therapy accompanied by neurothechnological anti-stress therapy (NAT). Patients from the NAT group received a regular audio-visual-vibrotactile stimulation as additional therapy (2 to 3 30-min sessions per week during 4 months). By the time of hospitalization, the groups did not differ in their general immune state. The percentages of CD3+ , CD4+ , CD8+ , CD16+ , CD19+ as well as indexes of phagocyte activity showed some changes after 2 and 4 months of therapy. The patients from both groups before treatment exhibited lymphocytosis, decreased phagocyte activity, when compared to healthy individuals. By the end of therapy (4 months), the patients from the NAT group showed increased phagocytosis by monocytes (p < 0.01) and granulocytes (p < 0.05) which approached values of healthy control. The study demonstrated also that efficiency of combined therapy was higher in the NAT vs. SDT group: closure of lung destruction cavities was observed in 90.5% of patients from the NAT group vs 45% of patients from the STD group. The results present evidence for combined implementation of neurothechnological anti-stress therapies as a supplementary method for the standard specific drug therapy in primary infiltrative lung tuberculosis

LYMPHOPENIA AS A FACTOR INVOLVED IN THE AUTOIMMUNITY DEVELOPMENT IN MURINE GRAFT VS. HOST DISEASE

Syngeneic splenocyte transplantation leads to lymphopenia development in intact mice owing to decreased proliferative activity of bone marrow hematopoietic progenitor cells. In the mice with induced chronic graft-versus-host disease (cGVHD) transfer of syngeneic lymphocytes has little or no effect on the level of already existing lymphopenia, but increases its duration. These results are in close agreement with the received evidences that transfer of syngeneic cells increases frequency of autoimmune glomerulonephritis at cGVHD. Thus, results of research speak in favor of conclusion that lymphopenia and initiated by it homeostatic proliferation play a pathogenetic role in the development of autoimmune reactions at cGVHD