Doses Of Γ-radiation Research Articles

RADIATION-STIMULATED CONVERSION TO SUPERIONIC STATE OF TlSe AND TlS CRYSTALS

The electrical properties of TlSe and TlS compounds were studied in a constant and alternating measuring field when exposed to various doses of gamma radiation in the temperature range of 300…400 K. In a constant electric field, a decrease in electrical conductivity with time was detected. Complex impedance spectra were measured in the frequency range 20…106 Hz. It is shown that in the studied range of temperatures, frequencies and doses of γ-radiation, conductivity is ionic in nature. The electrical properties of TlSe and TlS crystals are determined by the conductivity of Tl+1 ions and the accumulation of charge carriers near the blocking silver electrodes.

Design and synthesis of some novel quinazoline-thioacetamide derivatives as anticancer agents, apoptotic inducers, radio-sensitizers, and VEGFR inhibitors

Two novel sets of quinazoline-thioacetamides (3–12) and quinazoline-thioacetamides constituting sulfonamide tail (13–19), were synthesized as anti-proliferative agents targeting cancer through VEGFR-2 inhibition. The cytotoxicity of the newly constructed candidates was evaluated against MCF-7 cell line. Ten compounds 4–7, 9–11, 14, 16 and 18 (IC50 range= 36.41–76.05 µM) displayed better cytotoxic activity comparable to Doxorubicin (IC50 = 32.02 µM). Furthermore, 9 and 14 revealed promising biological activity and were selected to be tested for VEGFR-2 inhibition activity and demonstrated IC50 0.176 and 0.618 μg l-1, respectively, in compared to sorafenib‘s IC50 0.042 μg l-1. In addition, 9 and 14, were exposed to a γ-radiation dose (8 Gy), and their cytotoxicity was augmented following irradiation, validating the enhancing role of γ-radiation. Moreover, compound 9, as an influential demonstrative of the series, was estimated for the apoptotic inducer influence by examining the impact on caspase-3, it was observed to induce its level. Compound 9 enhanced the level of Bax level and diminshed the BCl2 level, in comparison to the positive control. Cell cycle analysis revealed that, compound 9 arrested the cell cycle at G2/M phase. Molecular docking assay was performed to investigate the possible binding mechanism within the VEGFR-2 active pocket. ADMET experiment was computed, to evaluate how closely the established compounds might resemble the drugs. This study shows that compound 9 has the potential to be an effective and sustainable anti-tumor agent. It can be used as a model for future research to modify its structure and investigating its biological properties further.

Low-Dose Ionizing γ-Radiation Elicits the Extrusion of Neutrophil Extracellular Traps.

Patients with cancer frequently undergo radiotherapy in their clinical management with unintended irradiation of blood vessels and copiously irrigated organs in which polymorphonuclear leukocytes circulate. Following the observation that such low doses of ionizing radiation are able to induce neutrophils to extrude neutrophil extracellular traps (NET), we have investigated the mechanisms, consequences, and occurrence of such phenomena in patients undergoing radiotherapy. NETosis was analyzed in cultures of neutrophils isolated from healthy donors, patients with cancer, and cancer-bearing mice under confocal microscopy. Cocultures of radiation-induced NETs, immune effector lymphocytes, and tumor cells were used to study the effects of irradiation-induced NETs on immune cytotoxicity. Radiation-induced NETs were intravenously injected to mice for assessing their effects on metastasis. Circulating NETs in irradiated patients with cancer were measured using ELISA methods for detecting MPO-DNA complexes and citrullinated histone 3. Irradiation of neutrophils with very low γ-radiation doses (0.5-1 Gy) elicits NET formation in a manner dependent on oxidative stress, NADPH oxidase activity, and autocrine IL8. Radiation-induced NETs interfere with NK cell and T-cell cytotoxicity. As a consequence, preinjection of irradiation-induced NETs increases the number of successful metastases in mouse tumor models. Increases in circulating NETs were readily detected in two prospective series of patients following the first fraction of their radiotherapy courses. NETosis is induced by low-dose ionizing irradiation in a neutrophil-intrinsic fashion, and radiation-induced NETs are able to interfere with immune-mediated cytotoxicity. Radiation-induced NETs foster metastasis in mouse models and can be detected in the circulation of patients undergoing conventional radiotherapy treatments. See related commentary by Mowery and Luke, p. 3965.

Gamma Irradiation-Mediated Alterations in Chemical Composition and Antimicrobial Efficacy of Zubaidi, a Wild Edible Desert Truffle (Terfezia boudieri), with Implications for Pharmaceutical Applications

In exploring the impact of γ-radiation on the biochemical makeup and antimicrobial attributes of Zubaidi truffle (Terfezia boudieri), this study delved into the nuanced interplay between irradiation doses, chemical components, and antimicrobial efficacy. This research scrutinized the influence of γ-radiation on the chemical constitutes and antimicrobial characteristics of Zubaidi truffle (Terfezia boudieri). By applying four distinct doses of γ-radiation (2.5, 5.0, 7.5, and 10 kGy), the study assesses various parameters, including phenols, flavonoids, total and reduced soluble sugars, crude and soluble protein, total amino acids, antioxidant activity, and the susceptibility of examined strains to irradiated and non-irradiated truffle extracts in comparison to standard antibiotics. The findings elucidate that γ-irradiation induces moderate adjustments in the chemical composition, coupled with a dose-dependent escalation in antioxidant activity. Remarkably, irradiated truffle extracts highlight antibiotic efficacy comparable to standard antibiotics, unveiling a nuanced correlation influenced by both radiation dosage and bacterial strain.

Quinazoline sulfonamide derivatives targeting MicroRNA-34a/MDM4/p53 apoptotic axis with radiosensitizing activity.

Aim: New quinazoline benzenesulfonamide hybrids 4a-n were synthesized to determine their cytotoxicity and effect on the miR-34a/MDM4/p53 apoptotic pathway. Materials & methods: Cytotoxicity against hepatic, breast, lung and colon cancer cell lines was estimated using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. Results: Compound 4d was the most potent against HepG2 and MCF-7 cancer cells, with potential apoptotic activity verified by a significant upregulation of miR-34a and p53 gene expressions. The apoptotic effect of 4d was further investigated and showed downregulation of miR-21, VEGF, STAT3 and MDM4 gene expression. Conclusion: The anticancer and apoptotic activities of 4d were enhanced post irradiation by a single dose of 8Gy γ-radiation. Docking analysis demonstrated a valuable affinity of 4d toward VEGFR2 and MDM4 active sites.

The impact of post-radiation high-temperature shear grinding on the thermal and mechanical properties of polypropylene

The effect of input doses of 60Co γ-radiation from 80 to 12,000 kGy on the thermophysical properties and thermal stability of samples of polypropylene granules and powder obtained by high temperature shear grinding of irradiated granules, as well as on the tensile strength properties of a plate made from irradiated granules and their corresponding powders, was studied. The thermophysical properties of the powder are determined by the changes introduced by radiation into the initial polymer granules. The effects of radiation in air (environments with oxygen) were studied. Grinding redistributes oxygen-containing functional groups from the surface layer of irradiated granules throughout the entire volume of the obtained powder leading to the destruction of polymer chains as there is a component due to thermal destruction of radiolyzed polymer chains. High-temperature shear grinding of irradiated granules has a significant effect on the product powder, reducing its thermal stability but increasing the tensile strength of plates pressed from it at low absorbed doses. The current work shows that radiation treatment coupled with high temperature shear grinding could be a method for modifying the properties of polymers so that polypropylene waste can be processed for other applications.

Dosimetric properties of Cr–La, Cr–Cu, and Cu–La ions codoped Ca9 Al (PO4)7 nanostructure

In the present work, Cr–La, Cr–Cu, and Cu–La ions codoped Ca9Al (PO4)7 nanostructures (symbolized as Cr–La, Cr–Cu, and Cu–La) were prepared using the sol-gel method for their dosimetric properties. X-ray diffraction (XRD) and transmission electron microscopy (TEM) results reflected the existence of the nanoparticle structure. This confirmed the successful sol-gel preparation method used. The surface morphological properties of the prepared samples were scrutinized by scanning electron microscopy (SEM). The presence and distribution of the constituent elements of the samples were determined using energy-dispersive X-ray (EDX) spectroscopy. The thermoluminescence (TL) sensitivity enhancement and homogenous properties of the prepared samples were assessed using a γ-radiation dose of 5 Gy. TL sensitivity of the Cr–Cu sample was found to be optimum. The relative standard deviations (RSD) of the homogenous study were found to be 6.5, 5.7, and 3.9% for Cr–La, Cr–Cu, and Cu–La, respectively, which were acceptable according to the ISO requirements (<10%). The dose-linearity response was investigated in 0.5 up to 20 Gy γ-dose ranges. The sample Cr–Cu had a good dose-linearity of up to 20 Gy while the others (Cr–La and Cu–La samples) had a dose-linearity of up to 13 Gy. The threshold doses (MDD) of the Cr–La, Cr–Cu, and Cu–La samples were computed and found to be approximately 110, 32, and 134 μGy, respectively. The photon attenuation parameters of the prepared samples were computed using the Phy-X PSD program, and the acquired data showed that the Ca9Al (PO4)7 composition had bone-equivalent material characteristics. Results of the dosimetric properties of Cr–La, Cr–Cu, and Cu–La co-doped Ca9Al (PO4)7 samples suggested that these compositions had potentially excellent TL characteristics to be used in various dosimetric applications across a broad range of gamma doses.

Thermoluminescence (TL) and electron paramagnetic resonance (EPR) of dumortierite sensitized by heat treatments

The present study presents the effect of heat treatment on TL and EPR of dumortierite. It was found that applying a heat treatment at 1200 °C for 1h, followed by slow cooling to room temperature, is optimal for improving its TL sensitivity. The glow curves of the sensitized dumortierite sample show TL emission bands centered at 350, 475, and 580 nm. The kinetic parameters of the TL peaks were obtained using the Tm-Tstop and deconvolution methods. In addition, sensitized dumortierite exhibits a linear response with γ-radiation dose and low fading in its TL response. Studies using the technique of EPR were carried out to investigate the defect center EPR signals observed after γ-irradiation. A single defect center with an axially symmetric g-tensor was observed with principal values g∥ = 2.0009 and g⊥ = 2.0017. The center was attributed to an F+ center and appears to correlate with the TL peak at 200 °C.

Alleviation of radiation combined skin injury in rat model by topical application of ascorbate formulation

Purpose This research endeavor was undertaken to elucidate the impact of an innovative ascorbate formulation on the regeneration process of full-thickness excision wounds in a rat model exposed to whole-body gamma irradiation, replicating conditions akin to combat or radiation emergency scenarios. Materials and Methods We established a comprehensive rat model by optimizing whole body γ-radiation doses (5–9 Gy) and full-thickness excision wound sizes (1–3 cm2) to mimic radiation combined injury (RCI). The developed RCI model was used to explore the healing potential of ascorbate formulation. The study includes various treatment groups (i.e., sham control, radiation alone, wound alone, radiation + wound, and radiation + wound + formulation). The ascorbate formulation was applied twice daily, with a 12-hour gap between each application, starting 1 hour after the initiation of the wound. The healing potential of the formulation in the RCI context was evaluated over 14 days through hematological, molecular, and histological parameters. Results The combination of a 5 Gy radiation dose and a 1 cm2 wound was identified as the optimal setting to develop the RCI model for subsequent studies. The formulation was used topically immediately following RCI, and then twice daily until complete healing. Treatment with the ascorbate formulation yielded noteworthy outcomes and led to a substantial reduction (p < .05) in the wound area, accelerated epithelialization periods, and an increased wound contraction rate. The formulation’s localized healing response improved organ weights, normalized blood parameters, and enhanced hematopoietic and immune systems. A gene expression study revealed the treatment up-regulated TGF-β and FGF, and down-regulated PDGF-α, TNF-α, IL-1β, IL-6, MIP-1α, and MCP-1 (p < .05). Histopathological assessments supported the formulation’s effectiveness in restoring cellular architecture and promoting tissue regeneration. Conclusion Topical application of the ascorbate formulation in RCI resulted in a significant improvement in delayed wound healing, leading to accelerated wound closure by mitigating the expression of inflammatory responses.

Liver and ovarian toxicities boosted by bisphenol and gamma radiation in female albino rats.

Bisphenol A (BPA), a carbon-based synthetic polymer compound, was newly classified as an environmental toxicant and an endocrine-disrupting chemical leading to abnormalities in cell proliferation, apoptosis, or migration that contributes to cancer development and progression. This study aims to evaluate the effect of the elevation of γ- radiation dose and BPA on the liver and ovaries of female rats. In this study, eighty female albino rats (130-150g) were used in this work. Rats in this experiment received BPA in ethanol (50mg/kg b. wt.) for 30days, day after day, and in the irradiated groups, animals were administered BPA and then exposed to γ- radiation in doses (2, 4, and 6Gy) one shot dose. Several members of the cytochrome family were examined. Exposure to γ-radiation and BPA showed an increase in cytochrome P450 and b5 fold change. Further, BPA and γ-radiation activate α and β estrogen receptors and also downregulate aromatase (CYT19) fold change. The current results also revealed that BPA and/or γ-radiation regulate the protein expression of the PI3K/Akt signaling pathway. The steroidogenic acute regulatory protein (StAR) appeared to be targeted by BPA and γ-radiation and its relative expression was elevated significantly by raising the γ-radiation dose. In conclusion, exposure to BPA, an endocrine-disrupting chemical, leads to marked toxicity. Additionally, toxicity is heightened by increasing the γ-radiation dose, either alone or in combination with BPA.

Morphological and functional changes in rat thyroid gland after a year following chronic exposure to low and intermediate doses of γ-radiation

Introduction Thyroid function depends on iodine uptake by the body as well as on exposure to various harmful environmental hazards (stress, ionizing radiation). Aim The aim of the work was to assess the effect of exposure to low and intermediate doses of external γ-radiation on the thyroid structure and function in young female rats at remote periods after radiation. Materials and Methods Forty female rats were used to study remote effects of external γ-radiation exposure during 20 d (at daily doses of 0.1, 0.25 and 0.5 Gy) on the functional activity (levels of thyroid hormones, iodine metabolism) and the morphological structure of the rat thyroid) after 12 months following the radiation exposure. Results An increase in thyroid mass and a decrease in total thyroid protein concentration along with a reduction of blood T3 and T4 was shown only in rat groups exposed to 0.25 and 0.5 Gy. Both the concentration of total iodine and its protein-bound fraction (1.2–1.4 fold, p < .01) and the protein-bound to total iodine ratio were decreased in the thyroids of all irradiated animals. The 0.1-Gy group showed elevated thyroperoxidase (TPO) activity along with increased catalase activity, which may indicate the activation of iodine oxidation by thyrocytes. Only the 0.5-Gy group demonstrated reduced urinary excretion of iodine (2.1 fold, p < .01). The reduction of thyroid function at radiation doses of 0.25 and 0.5 Gy was characterized by a microfollicular structure and the development of atrophic changes in the parenchyma, desquamation of thyroid epithelium and an increase in epithelium proliferation. The diameter of the thyrocyte nuclei was increased in rats exposed to 0.25 and 0.5 Gy, which indicates functional tension of thyrocytes. Conclusion Our research shows that after a year, the exposure to external γ-radiation of 0.1, 0.25 and 0.5-Gy caused changes in the structure and function of the rat thyroid which are manifested by the development of hypothyroiditis (0.5 Gy), ‘subclinical’ hypothyroiditis (0.25 Gy) and functional tension of thyrocytes. The mechanisms of thyroid dysfunction - impaired- uptake of iodine and its organification against the background of activation of free radical processes – suggest disturbances in the function of the sodium/iodide symporter (NIS), TPO and thyroglobulin synthesis. In contrast to the intermediate doses, the effects of the 0.1-Gy dose were mostly found at the remote periods compared to the earlier periods (180 days).

Individual and combinative effect of NaCl and γ-radiation on NADPH-generating enzymes activity in corn (Zea mays L.) sprouts

Being a universal reducing agent nicotinamide adenine dinucleotide phosphate hydrogen (NADPH) plays an important role in the cellular metabolism and the implementation of anti-stress reactions in plants. There are only a few enzymes that ensure the NADPH pool formation in cells. Among them, the most important are glucose-6-phosphate dehydrogenase (G6PDH, EC 1.1.1.49), malate dehydrogenase decarboxylating (DMDH, malic enzyme, EC 1.1.1.40) and NADP-isocitrate dehydrogenase (NADP-IDH, EC 1.1.1.42). The presented investigation is devoted to studying the influence of the individual and combinative effects of NaCl and γ-radiation as abiotic stress factors on biometric indicators and activity of these NADPH-generating enzymes, on organic content, and the formation of paramagnetic centers as defense reaction in corn (Zagatala-68 genotype) sprouts. It was found that 100 mM NaCl had an inhibitory effect on the development of sprouts. Relatively lower doses (50 Gy and 100 Gy) of γ-radiation had a positive, but its higher doses (150 Gy and 200 Gy) had a negative effect on this process. 500 Gy was a lethal dose (LD) for the corn sprouts. Combinative stress in all cases considerably delayed the development of sprouts. G6PDH showed the highest activity in the first, whereas, NADP-IDH showed the same activity in the last days of the experiment. All three enzymes, especially the G6PDH, have been activated in both root and stem tissues under the influence of stress factors (either radiation or salt). Combinative stress (γ-radiation + salt) also led to an induction of these activities which was necessary to neutralize the negative consequences of stress factors. Stress factors in all cases also had a negative effect on the content of organic matter in seedlings. Ionizing gamma radiation, which resulted in the formation of new paramagnetic centers as an anti-stress defense reaction in many cases was observed in wheat seedlings, but not in corn sprouts, which clearly shows that there are some differences in the protective mechanisms of these C3- and C4-types of plants to γ-radiation.

Breaking the cycle of excessive conservatism: Evaluating the γ-radiation dose from building materials

Radionuclide content in building materials is regulated in most European countries by calculating the activity concentration index. The I-index does not account for the properties nor the application of the material but provides a conservative evaluation of the annual γ-radiation dose. Using a Monte Carlo toolkit, EGSnrc, this study calculated doses from building materials in less conservative set-ups by focusing on materials with a potential for recycling NORM residues, such as Portland cement, ceramics, gypsum, and mineral insulation. It was observed that proper consideration of building material geometry strongly affected the indoor dose rate. Regulating low-density materials and finishing materials such as gypsum and insulation under the same framework as high-density and high-bulk materials proved problematic because the doses differ by orders of magnitude. The current reference values for radionuclide concentrations used in calculating the I-index do not apply to most construction materials. For many types of building materials, higher radionuclide concentrations in the material could be allowed without contradicting the annual effective dose reference for the public. This illustrates the potential for boosting the use of NORM residues in various construction applications.

The role of mouse-like rodents in the Chornobyl Exclusion Zone in the spread of blood-borne diseases

A feature of the conducted research is the study of a topical issue – the influence of external and internal factors on the prevalence of pathogens of blood-parasitic diseases. One of the most important external factors of influence is the exposure dose of γ-radiation, since the catching of mouse-like rodents was carried out at the landfills of the drained bed of the cooling reservoir of the Chernobyl Nuclear Power Plant. Therefore, the aim of the work was to study mouse-like rodents for the presence of causative agents of blood-parasitic diseases in natural populations under the influence of radioecological conditions of man-made transformation of the cooling reservoir of the Chernobyl Nuclear Power Plant. Mouse-like rodents of the genera Apodemus and Myodes were studied from three different locations of the cooling pond using parasitological methods. Radiological methods were used to determine the level of contamination of the specified three places where mouse-like rodents were caught using the γ- and β-dosimeter Pripyat RKS 20.3. Examination of blood smears of mouse-like rodents from three experimental polygons of the cooling reservoir of the Chernobyl Nuclear Power Plant revealed the presence of pathogens of blood-parasitic diseases in 93.8% of animals. In particular, such pathogens as Rickettsia spp., Ehrlichia spp., Bartonella spp., Babesia spp., Hepatozoon spp., Haemobartonella (Mycoplasma) spp., were identified. and spirochetes. The prevalence of zoonotic agents among mouse-like rodents of the Chernobyl Zone of radioactive contamination, as well as its dependence on the level of radioecological pollution of the respective landfills, was established. Therefore, according to the results of the conducted research, the presence of causative agents of blood-parasitic diseases among mouse-like rodents, which are both intermediate and their definitive hosts, including those from dangerous zoonoses, which, subject to the application of timely and complex preventive measures, will prevent human infection

The use of the aquatic plant Elodea canadensis to assess the effects of low-dose gamma irradiation

Responses of cytogenetic and growth endpoints of the aquatic plant Elodea canadensis were studied using the plants collected from non-contaminated control areas of the Yenisei River and exposed to external γ-radiation for 11–13 days in the laboratory. Elodea canadensis was exposed to 0.5–25 mGy/day γ-radiation dose rates from a 137Cs source. The total number of aberrant cells and total root length were more sensitive elodea endpoints to γ-radiation than total shoot length and mitotic index of elodea. Radiation sensitivity of elodea can be compared with the sensitivity of such a Reference Plant as Wild Grass (1–10 mGy/day) recommended by the ICRP. Thus, the aquatic plant Elodea canadensis can be used as a radiation bioindicator.

Extractability of Rice Husk Waste Using Green Gamma Radiation for Dye Elimination in Laboratory-Scale Sorption System: Equilibrium Isotherm and Kinetic Analysis.

Nowadays, the use of natural materials and especially "waste" valorization has evolved and attracted the wide attention of scientists and academia. In this regard, the use of rice husk (RH) powder as a naturally abundant and cheap byproduct material is gaining superior attention. However, improving the physicochemical properties of such RH is still under research. In the current investigation, the modification of rice husk (RH) via γ-irradiation has shown to be a promising green tool to meet such a need. Clean, prepared, powdered RH samples were subjected to various γ-radiation doses, namely 5, 10, 15 and 25 kGy, and the corresponding samples were named as RH-0, RH-5, RH-10, RH-15, RH-15 and RH-25. Then, the samples were characterized via scanning electron microscopy (SEM). After irradiation, the samples showed an increase in their surface roughness upon increasing the γ-radiation up to 15 kGy. Furthermore, the sorption capacity of the irradiated RH samples was investigated for eliminating Urolene Blue (UB) dye as a model pharmaceutical effluent stream. The highest dye uptake was recorded as 14.7 mg/g, which corresponded to the RH-15. The adsorption operating parameters were also investigated for all of the studied systems and all adsorbents showed the same trend, of a superior adsorption capacity at pH 6.6 and high temperatures. Langmuir and Freundlich isotherm models were also applied for UB adsorption and an adequate fitted isotherm model was linked with Langmuir fitting. Moreover, the pseudo-second-order kinetic model provided the best fit for the adsorption data. Experimental assays confirmed that the UB dye could be successfully eradicated feasibly from the aqueous stream via a sustainable green methodology.

Influence of High γ-Radiation Doses on the Germination and Toxic Properties of Oat Seeds

Influence of High γ-Radiation Doses on the Germination and Toxic Properties of Oat Seeds

Small γ-Radiation Doses Impact in the Conditions of Controlled Micropenological Octores of Spring Barley

Barley, characterized by early ripening, cold and drought resistance, is an important agricultural grain crop. Ionizing radiation use in the pre-sowing seed treatment technology is promising in order to control pathogens and increase the grain crops yield. The study aims at developing a microphenological sprouting phases scale of spring barley variety in Remembrance of Vyacheslav Chepelev treated with small doses of gamma radiation under controlled ontogeny conditions. The authors gave the concepts interpretation of “sprouted grain” and “grain sprouts”. To remove the dormant state of the original seeds (grains) of spring barley variety in Remembrance of Vyacheslav Chepelev harvested in 2021 and zoned in the Sverdlovsk region, a man treated it with small doses of γ-radiation ionizing (5, 10, 15 and 20 Gy) by a radiation source 60Co. The researchers developed a microphenological sprouting phases scale of spring barley grains with the dry grain phase and the micrograin phase introduced; and classification levels differentiated. A man revealed that the change in grain moisture and grain germ in all microphenophases was comparable with the results obtained during barley sprouting. The most intensive water absorption occurs at the swelling phase with an increase in grain moisture by 2.7 times and in the embryo by 9.3 times. Spring barley grains radiostimulation has an impact on the grain sprouting due to increased germination energy. The authors determined that after 5 days there was a maximum increase in the germination capacity to (92 ± 2) % and (94 ± 2) % in barley grains samples treated with doses of 5 and 10 Gy, respectively, with lower values when processing grains with doses of 15 Gy and 20 Gy. A man ascertained inhibitory effect of a radiation dose of 20 Gy. Despite a higher germination energy index of 75 % in barley grains treated with a dose of 20 Gy, and unlike untreated grains – 74 %, the germination ability in radiation-treated grains was 4 % lower. The germination rate of the first seed is 3 days on average.

Low dose γ-radiation induced effects on wax moth (Galleria mellonella) larvae

Larvae of the greater wax moth Galleria mellonella are common pests of beehives and commercial apiaries, and in more applied settings, these insects act as alternative in vivo bioassays to rodents for studying microbial virulence, antibiotic development, and toxicology. In the current study, our aim was to assess the putative adverse effects of background gamma radiation levels on G. mellonella. To achieve this, we exposed larvae to low (0.014 mGy/h), medium (0.056 mGy/h), and high (1.33 mGy/h) doses of caesium-137 and measured larval pupation events, weight, faecal discharge, susceptibility to bacterial and fungal challenges, immune cell counts, activity, and viability (i.e., haemocyte encapsulation) and melanisation levels. The effects of low and medium levels of radiation were distinguishable from the highest dose rates used – the latter insects weighed the least and pupated earlier. In general, radiation exposure modulated cellular and humoral immunity over time, with larvae showing heightened encapsulation/melanisation levels at the higher dose rates but were more susceptible to bacterial (Photorhabdus luminescens) infection. There were few signs of radiation impacts after 7 days exposure, whereas marked changes were recorded between 14 and 28 days. Our data suggest that G. mellonella demonstrates plasticity at the whole organism and cellular levels when irradiated and offers insight into how such animals may cope in radiologically contaminated environments (e.g. Chornobyl Exclusion Zone).

Influence of High γ-Radiation Doses on the Germination and Toxic Properties of Oat Seeds

The effect of γ-radiation doses from 100 to 3000 kGy on the toxic properties and germination of oat seeds has been + studied. A tendency has been noted for a 15–25% decrease in the germination of oat seeds under laboratory conditions in the range of presowing irradiation doses of 10–700 Gy. After irradiation with a dose higher than 1 kGy, the seeds lost their ability to germinate. Curves reflecting the dependences of the length of oat stalk on the dose of presowing irradiation of seeds exhibited two areas with a characteristic separation point at doses of 70 Gy, below which the degree of influence of the irradiation dose on the height ofseedlings and their growth ability increased noticeably. The toxicity of radiolyzed oat grains depended on the dose of γ-irradiation of grains and the mode of additional feeding of experimental mice. It was established that a γ-radiation dose lower than 100 kGy did not affect the toxicity of fodder oat grain, and radiation doses of 400 kGy or higher made irradiated grains unsuitable for feeding mice without additional feeding with compoundfeed. The higher the dose of γ-irradiation of oat grain, the earlier experimental mice died en masse: after 14–15, 9, 8, and 6 days of feeding at radiation doses of 580, 1000, 1700, and 3170 kGy, respectively. The reason for the toxic manifestation of irradiated oat grains and the death of mice treated with irradiated grain,apparently, can be the formation of toxic substances in oat grains irradiated with high doses due to the occurrence of physicochemical reactions in the course and after irradiation and a decrease in the nutritional value of products associated with the destruction of vitamins and other food components. Intoxication after consumption of oat grains irradiated with a dose of 400–3170 kGy was clinically manifested by depression, lethargy of animals, and signs of dehydration and diarrhea against the background of a strong decrease in the body weight of experimental animals. It is expedient to use radiolyzed oat grains for technical purposes, especially, if they were treated with high doses of radiation