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The rust flour beetle Tribolium castaneum (Herbst) (Coleoptera: Tenebrionidae) is the most prevalent pest in stored food for human and animal consumption. The current study was conducted to determine the efficacy of microwave energy and gamma radiation on T. castaneum larvae, pupae, and adults. Microwave was applied with exposure times of 30, 60, 120, 180, 240, and 300 sec. at the powers of 180, 300, and 450 W. In addition, gamma radiation was applied at a dosage of 200, 400, 600, 800, and 1000 Gray. Mortality percentage was recorded after 1, 2, 3, 4, 7, and 10 days, and LD50 was recorded after 7 days of treatment. The results indicated that the mortality of T. castaneum increased with increasing doses and exposure time. The mortality of T. castaneum increased, reaching 100% at power levels of 300 s and 450 W. The LT50 and LT90 decreased as power levels and exposure time increased. Moreover, the dosage of 1000 Gray caused 85.0 and 65.0% mortality after 7 days of irradiation for larvae and adult stages. The required dosage of gamma radiation to kill 50% (LD50) of adults after 7 days was 580.1 Gray. Therefore, the use of microwave energy and gamma radiation is a very important alternative method to protect stored grains and their products against T. castaneum. [ABSTRACT FROM AUTHOR]

Highlights • Gamma irradiation increased the shelf life of pomegranate arils. • Gamma irradiation reduced microbial load in pomegranate arils during the shelf life. • The effects of gamma irradiation in lower doses on the quality of arils were not considerable. • Lower activity of polyphenol oxidase was found in gamma irradiated samples. Abstract In the present study, the effect of gamma irradiation on the reduction of microbial population and the maintenance of qualitative attributes of arils in pomegranate cv. Malas-e-Saveh in post-harvest stage was investigated. For this purpose, pomegranate arils, after being separated from the fruit, were irradiated with gamma doses of 0 (as control), 1, 3 and 5 kGy, packed in polyethylene container using cellophane film, and then maintained at 4 °C and relative humidity above 80%. After 7 and 14 days of storage, the arils were removed from the storage and were examined for count of bacteria, fungi and yeasts, anti-oxidant properties and other qualitative characteristics. The results indicated that gamma irradiation in all doses significantly reduced the population of bacteria, fungi and yeasts when compared with control. However, in comparison with control, samples irradiated with gamma irradiation, especially in high doses, contained lower soluble solids, titratable acidity, phenol, anthocyanin and ascorbic acid contents, antioxidant capacity and activity of polyphenol oxidase enzyme, but higher hydrogen peroxide content. Therefore the effects of gamma irradiation in low dose (1 kGy) on the quality of arils were not considerable and would be effective in increasing the shelf life of pomegranate arils. [ABSTRACT FROM AUTHOR]

The effect of irradiation on oxidants and antioxidants in selected tissues and a possible protective effect of curcumin on these indices were investigated. A total of 28 rats were divided into 3 groups; group 1 was control; group 2 was the irradiation group, saline was administered intraperiotenally (i.p.) for three days and then, 9 Gy gamma irradiation was applied; group 3 was the irradiation + curcumin group: curcumin was given i.p. for three days at 200 mg/kg body weight and then the same dose of irradiation was applied. A significant increase in malondialdehyde (MDA) was detected in the liver, kidney, and brain tissues of the rats as a result of irradiation (P < 0.01). Glutathione peroxidase (GSH-Px) activity in all the tissues (except for kidneys) decreased (P < 0.01), liver SOD (superoxide dismutase) activity decreased (P < 0.05), and GSH (glutathione) levels in kidney and ovary tissues (P < 0.001) significantly increased. While curcumin administration returned the increased MDA levels in the kidneys and brain in result of irradiation to normal (P < 0.01), it did not return the increased MDA levels in the liver tissue to normal (P < 0.001) despite significantly reducing them. While decreased GSH-Px and SOD activity in the liver in result of irradiation increased with the addition of curcumin (P < 0.05), increased GSH levels in the kidneys and ovaries returned to control levels (P < 0.001). When MDA values were examined, it was found that the addition of curcumin protected the liver, kidneys and brain from the oxidative damage caused by irradiation. [ABSTRACT FROM AUTHOR]

Gamma-tocotrienol (GT3), a naturally occurring vitamin E isomer, a promising radioprotector, has been shown to protect mice against radiation-induced hematopoietic and gastrointestinal injuries. We analyzed changes in protein expression profiles of spleen tissue after GT3 treatment in mice exposed to gamma radiation to gain insights into the molecular mechanism of radioprotective efficacy. Male CD2F1 mice, 12-to-14 weeks old, were treated with either vehicle or GT3 at 24 h prior to 7 Gy total-body irradiation. Nonirradiated vehicle, nonirradiated GT3 and age-matched naïve animals were used as controls. Blood and tissues were harvested on days 0, 1, 2, 4, 7, 10 and 14 postirradiation. High-resolution mass-spectrometry-based radioproteomics was used to identify differentially expressed proteins in spleen tissue with or without drug treatment. Subsequent bioinformatic analyses helped delineate molecular markers of biological pathways and networks regulating the cellular radiation responses in spleen. Our results show a robust alteration in spleen proteomic profiles including upregulation of the Wnt signaling pathway and actin-cytoskeleton linked proteins in mediating the radiation injury response in spleen. Furthermore, we show that 24 h pretreatment with GT3 attenuates radiation-induced hematopoietic injury in the spleen by modulating various cell signaling proteins. Taken together, our results show that the radioprotective effects of GT3 are mediated, via alleviation of radiation-induced alterations in biochemical pathways, with wide implications on overall hematopoietic injury. [ABSTRACT FROM AUTHOR]

Gamma radiation induces protein changes that enhance immunogenicity for venoms, used in antivenin production. Coccidian parasites exposed to gamma radiation elicit immune response with protection in mice and man, but without studies on the effect of gamma radiation in soluble acellular extracts or isolated proteins. Toxoplasmosis is a highly prevalent coccidian disease with only one vaccine for veterinary use but with remaining tissue cysts. Total parasite extracts or recombinant proteins used as immunogen induce usually low protection. Here, we study gamma radiation effect on T. gondii extracts proteins (STAG) and its induced immunity in experimental mice models. By SDS-PAGE, protein degradation is seen at high radiation doses, but at ideal dose (1500 Gy), there are preservation of the antigenicity and immunogenicity, detected by specific antibody recognition or production after mice immunization. Immunization with STAG irradiated at 1500 Gy induced significant protection in mice immunized and challenged with distinct T. gondii strains. In their blood, higher levels of specific CD19 + , CD3 + CD4 + and CD3 + CD8 + activated cells were found when compared to mice immunized with STAG. Irradiated T. gondii tachyzoites extracts induce immune response and protection in mice in addition, could be a feasible alternative for Toxoplasma vaccine. [ABSTRACT FROM AUTHOR]

The aim of this study was to determine the deleterious effects of nonlethal gamma radiation on testes and their possible inhibition by Haberlea rhodopensis extract (HRE). For this goal, 20 male New Zealand rabbits were divided into 4 groups: group I - untreated, group II - treated with HRE extract, group III - exposed to 2 Gy gamma radiation, group IV - treated with HRE (0.24 g/kg b.w.) two hours before irradiation with 2 Gy. Exposure of animals to 2.0 Gy gamma radiation resulted into significant decrease in tubular diameter and the area of the seminiferous tubules on the 15th day after irradiation. HRE pretreatment resulted in significant increase in tubular diameter and the area of the seminiferous tubules as compared to the irradiated group. Radiation-induced histological lesions in testicular architecture were more severe in irradiated only than in HRE-treated irradiated rabbits. HRE administration before irradiation significantly attenuated radiation-induced histological damages in testes. These observations indicate the radioprotective potential of Haberlea Rhodopensis leaves extract against the effects of whole body gamma irradiation on rabbit testicular histostructure. [ABSTRACT FROM AUTHOR]

The radiation-induced adaptive response (RI-AR) is a non-targeted effect which is outside the scope of the classical Linear-No-Threshold (LNT) dose-response paradigm. However, the mechanisms of the RI-AR are not well understood. We have studied the RI-AR in quiescent human peripheral blood mononuclear cells (PBMCs). PBMCs in G 0 phase were ‘primed’ with a low dose (100 mGy gamma radiation) and then, after an ‘adaptive window’ of 4 h, ‘challenged’ with a high dose (2 Gy). A small (5.7%) increase in viability and a decrease in DNA strand breaks were seen in primed cells, compared to non-primed cells. This was consistent with lower levels of reactive oxygen species, higher mitochondrial membrane potential, and increased activity of antioxidant enzymes such as catalase, superoxide dismutase, thioredoxin reductase, and glutathione peroxidase, in the primed cells. Reduced oxidative stress in primed PBMCs correlated with greater nuclear translocation of the redox-sensitive transcription factors Nuclear factor kappa B (NF-κB) and Nuclear factor E2-related factor 2 (Nrf2). Distinct differences in responses were seen in PBMCs irradiated with low dose (100 mGy) and high dose (2 Gy). These findings provide insight into the mechanisms of radioadaptation in human cells. [ABSTRACT FROM AUTHOR]

Treatment of cancer often requires exposure to radiation, which has several limitations involving non-specific toxicity toward normal cells, reducing the efficacy of treatment. Recent studies synthesize new quinolone derivatives to satisfy other purposes such as treatment of inflammatory and malignant diseases. The main purpose of the present study is to evaluate the effect of a new quinolone derivative; 2-(1-Ethyl-4-hydroxy-2-oxo-1,2-dihydroquinolin-3-yl)-2-oxoacetic acid (EHQA) and its possible mechanism against gamma radiation (IRR) and cisplatin (Cis) induced nephrotoxicity and neurotoxicity in mice. The structure of the newly synthesized quinolone derivative was elucidated by microanalytical and spectral data, which were found consistent with the assigned structures. Exposure to Cis and IRR significantly induced renal damage manifested by a significant increase in levels of urea and creatinine. Moreover, the exposure to both Cis and IRR significantly decreased the levels of anti-apoptotic protein; Bcl-2 in both renal and brain tissue homogenate accompanied by activation of an inflammatory marker; IL-17. Immunophenoting results showed an activation of T- lymphocytes marker; CD3 and B-lymphocytes marker; CD19. Interperitonial administration of EHQA significantly ameliorated the above-mentioned parameters. Overall, the present results indicated that EHQA is a promising anti-inflammatory and anti-apoptotic agent. From the obtained results it can be concluded that EHQA could be a candidate as immunomodulatory agents. Further studies are required to establish its molecular mechanism. [ABSTRACT FROM AUTHOR]

The biological effects of gamma radiation may exert damage beyond that of the individual through its deleterious effects on reproductive function. Impaired reproductive performance can result in reduced population size over consecutive generations. In a continued effort to investigate reproductive and heritable effects of ionizing radiation, we recently demonstrated adverse effects and genomic instability in progeny of parents exposed to gamma radiation. In the present study, genotoxicity and effects on the reproduction following subchronic exposure during a gametogenesis cycle to 60 Co gamma radiation (27 days, 8.7 and 53 mGy/h, total doses 5.2 and 31 Gy) were investigated in the adult wild-type zebrafish ( Danio rerio ). A significant reduction in embryo production was observed one month after exposure in the 53 mGy/h exposure group compared to control and 8.7 mGy/h. One year later, embryo production was significantly lower in the 53 mGy/h group compared only to control, with observed sterility, accompanied by a regression of reproductive organs in 100% of the fish 1.5 years after exposure. Histopathological examinations revealed no significant changes in the testis in the 8.7 mGy/h group, while in 62.5% of females exposed to this dose rate the oogenesis was found to be only at the early previtellogenic stage. The DNA damage determined in whole blood, 1.5 years after irradiation, using a high throughput Comet assay, was significantly higher in the exposed groups (1.2 and 3-fold increase in 8.7 and 53 mGy/h females respectively; 3-fold and 2-fold increase in 8.7 and 53 mGy/h males respectively) compared to controls. A significantly higher number of micronuclei (4–5%) was found in erythrocytes of both the 8.7 and 53 mGy/h fish compared to controls. This study shows that gamma radiation at a dose rate of ≥ 8.7 mGy/h during gametogenesis causes adverse reproductive effects and persistent genotoxicity (DNA damage and increased micronuclei) in adult zebrafish. [ABSTRACT FROM AUTHOR]

To investigate the potential protective effect of kaempferol, a representative flavonoid, against radiation induced mortality and injury in vivo and vitro .C57BL/6 male mice and human umbilical venous endothelial cells (HUVECs) were pretreated with kaempferol before radiation. We found that kaempferol can effectively increase 30-day survival rate after 8.5 Gy lethal total body irradiation (TBI). Mice were sacrificed at 7th day after 7 Gy TBI, we found kaempferol against radiation-induced tissues damage, by inhibiting the oxidative stress, and attenuating morphological changes and cell apoptosis. In vitro , kaempferol increased HUVECs cell viability and decrease apoptosis. It also mitigated oxidative stress and restored the abnormal expression of prx-5, Cyt-c, Caspase9 and Caspase3 in mRNA and protein level in HUVECs after radiation. Taken together, it suggests kaempferol can protect against gamma-radiation induced tissue damage and mortality. The present study is the first report of the radioprotective role of kaempferol in vivo and vitro . [ABSTRACT FROM AUTHOR]

Double strand breaks (DSBs) in E. coli chromosome (such as those induced by gamma rays) are repaired by recombination repair, during which a certain amount of DNA gets degraded. We monitored DNA degradation in gamma-irradiated cells to assess processing of DSBs. DNA degradation in irradiated cells is regulated by RecA protein concentration and its affinity of ssDNA binding, as well as by exonucleases that trim 3′-terminated ss tails. Here we determined the effects of proteins that affect formation and stability of RecA nucleofilaments on DNA degradation and cell survival. RecF and UvrD suppressed DNA degradation through RecA protein function and SOS induction, while also improving gamma survival. RecF and UvrD function in one pathway. Acting along with RecF, RecX suppressed DNA degradation and stimulated gamma-survival, which also depends on RecA protein and SOS induction. Furthermore, we determined a role in DNA degradation of several proteins that participate in DSB repair. RecN was required for DNA repair and for degradation suppression, acting on the RecABCD pathway. Furthermore, we show that SSB protein overproduction did not affect DNA degradation. Inactivation of RecG and RuvABC, proteins that catalyze the postsynaptic phase of recombination repair of DSBs, also did not affect DNA degradation, suggesting that once formed, recombination intermediates are not subject to DNA degradation, and that the postsynaptic phase is an irreversible, single-round process, unlike the presynaptic phase, which is mostly repetitive. [ABSTRACT FROM AUTHOR]

The superhydrophobic coatings with high gamma radiation stability were prepared by using epoxy/polydimethylsiloxane (EP/PDMS) resins as the matrix and silica nanoparticles as the fillers. The nanocomposite coatings exhibit superhydrophobicity with a high water contact angle (WCA) of 154° and a low sliding angle of 7°. With the amount of SiO 2 increasing from 0 to 30%, the surface shows the hierarchically structure gradually and its roughness raised from 4 nm to 278 nm. And little change in the WCA of the coatings (from 155° to 149°) was observed when the pH of the droplets varied from 2 to 14. In addition, the coatings also show good adhesion grade (5B), high hardness (6H) and outstanding stability for high dose gamma radiation. [ABSTRACT FROM AUTHOR]

The aim of this study was to evaluate the effect of gamma radiation on the physico-chemical parameters in a mixed beverage (white or red grape juice + soy milk). The radiation doses were used: 1, 3, 6 and 9 kGy. Most of the parameters evaluated did not change in both beverages at different doses, with the exception of the 9 kGy dose that reduced the antioxidant capacity and the phenolic compounds, and increased the peroxidase. Thus, the gamma radiation can be used in mixed beverages, but doses below 9 kGy, avoiding changes in physico-chemical quality. [ABSTRACT FROM AUTHOR]

Pregnant C57BL/6JJcl mice were exposed to γ rays at low dose rate (20 mGy/day, LDR) or medium dose rate (200 and 400 mGy/day, MDR) from gestation day (GD) 0-18 to total accumulated doses of 360, 3,600 and 7,200 mGy, respectively. An additional group of pregnant mice were acutely exposed to 2 Gy at high dose rate (HDR) of 0.77 Gy/min on GD 11. In experiment 1, fetuses collected via cesarean section on GD 18 were examined for external and skeletal abnormalities. While the results of LDR exposure (20 mGy/day) did not significantly differ from the nonirradiated controls in all parameters examined, MDR (200 and 400 mGy/day) and acute HDR (2 Gy) exposure caused growth retardation and significantly increased incidence of unossified bones. Increased incidence of external abnormalities was observed only in the acute HDR group. In experiment 2, the dams were allowed to give birth and the pups were clinically monitored and weighed periodically until 10 weeks of age when they were sacrificed and subjected to pathological examination. Pups exposed at MDRs of 200 and 400 mGy/dayand at acute HDR of 0.77 Gy/min had lower bodyweights from weaning (3 weeks) to 10 weeks of age except for females exposed to 400 mGy/day MDR. None of the pups exposed to an acute 2 Gy dose on GD 11 survived to 10 weeks of age. Histopathological changes were not significantly different between the nonirradiated control and the 20 mGy/day LDR groups. However, at both MDR exposures of 200 and 400 mGy/day. gonadal (testes and ovary) hypoplasia/atrophy was observed in all the 10-week-old pups. Our results show that in utero LDR exposure to 20 mGy/day for the entire gestation period did not cause any significant effect in pups when compared to the nonirradiated controls up to 10 weeks of age. However, pups exposed in utero to MDRs showed dose-related growth retardation with delayed ossifications (400 mGy/day) and gonadal hypoplasia/atrophy. These findings suggest that increased post-implantation loss in dams exposed at MDR is due to early embryonic deaths resulting in early resorption. [ABSTRACT FROM AUTHOR]

Mortality from circulatory disease (CD), ischemic heart disease (IHD) and cerebrovascular disease (CeVD) was investigated in relationship to cumulative doses of external gamma radiation and internal alpha radiation to the liver from deposited plutonium over long follow-up periods in two large cohorts of nuclear workers: the Russian Mayak Worker Cohort (MWC) and the UK Sellafield Worker Cohort (SWC). The MWC comprised 22,374 workers (74.6% males) with 5,123 CD deaths registered during 842,538 person-years of follow-up, while the SWC comprised 23,443 workers (87.8% males) with 2,322 CD deaths registered during 602,311 person-years of follow-up. Dose estimates for external gamma radiation and internal alpha radiation to the liver were calculated via a common methodology, in accordance with an agreed protocol. The mean cumulative external Hp(10) dose was 0.52 Sv for the MWC and 0.07 Sv for the SWC, while the mean cumulative internal dose was 0.19 Gy for the MWC and 0.01 Gy for the SWC. Categorical relative risks (RR) and excess relative risks (ERR) per unit dose were estimated for each cohort and for the pooled cohort when appropriate. The dose responses for CD, IHD and CeVD in relationship to internal alpha-particle dose did not differ significantly from the null for either the MWC, the SWC or the pooled plutonium worker cohort. The ERR/Sv estimates in relationship to external exposure were significantly raised for both cohorts (marginally so for the MWC) for CD and IHD (but not for CeVD), but differed significantly between the two cohorts, the estimate for the SWC being approximately ten times greater than that for the MWC. Examination of the ERR/Sv estimates for two periods of first employment at the two facilities revealed that the significant heterogeneity was confined to the earlier sub-cohorts, and that the estimates for the later sub-cohorts were compatible. The two sub-cohorts for the later first-employment periods were pooled, producing risk estimates that were raised, but not significantly so: ERR/Sv for CD, IHD and CeVD of 0.22 (95% CI: -0.01, 0.49), 0.22 (95% CI: -0.06, 0.57) and 0.24 (95% CI: -0.17, 0.80), respectively. The reasons for the complex pattern of results found in this study are unclear. Among potential explanations are the influence of differences in background CD mortality rates, an effect of other occupational factors, substantial uncertainties in doses, particularly during earlier periods of operations, as well as confounding and/or modifying factors that were not taken into account in the current analysis. [ABSTRACT FROM AUTHOR]

Managed honey bee ( Apis mellifera ) populations are currently facing unsustainable losses due to a variety of factors. Colonies are challenged with brood pathogens, such as the fungal agent of chalkbrood disease, the microsporidian gut parasite Nosema spp., and several viruses. These pathogens may be transmitted horizontally from worker to worker, vertically from queen to egg and via vectors like the parasitic mite, Varroa destructor . Despite the fact that these pathogens are widespread and often harbored in wax comb that is reused from year to year and transferred across beekeeping operations, few, if any, universal treatments exist for their control. In order to mitigate some of these biological threats to honey bees and to allow for more sustainable reuse of equipment, investigations into techniques for the sterilization of hive equipment and comb are of particular significance. Here, we investigated the potential of gamma irradiation for inactivation of the fungal pathogen Ascosphaera apis , the microsporidian Nosema ceranae and three honey bee viruses ( Deformed wing virus [DWV], Black queen cell virus [BQCV], and Chronic bee paralysis virus [CBPV]), focusing on the infectivity of these pathogens post-irradiation. Results indicate that gamma irradiation can effectively inactivate A. apis , N. ceranae , and DWV. Partial inactivation was noted for BQCV and CBPV, but this did not reduce effects on mortality at the tested, relatively high doses. These findings highlight the importance of studying infection rate and symptom development post-treatment and not simply rate or quantity detected. These findings suggest that gamma irradiation may function as a broad treatment to help mitigate colony losses and the spread of pathogens through the exchange of comb across colonies, but raises the question why some viruses appear to be unaffected. These results provide the basis for subsequent studies on benefits of irradiation of used comb for colony health and productivity. [ABSTRACT FROM AUTHOR]

Ionizing radiation causes a variety of effects, including DNA damage associated to cancers. However, the effects in progeny from irradiated parents is not well documented. Using zebrafish as a model, we previously found that parental exposure to ionizing radiation is associated with effects in offspring, such as increased hatching rates, deformities, increased DNA damage and reactive oxygen species. Here, we assessed short (one month) and long term effects (one year) on gene expression in embryonic offspring (5.5 h post fertilization) from zebrafish exposed during gametogenesis to gamma radiation (8.7 or 53 mGy/h for 27 days, total dose 5.2 or 31 Gy) using mRNA sequencing. One month after exposure, a global change in gene expression was observed in offspring from the 53 mGy/h group, followed by embryonic death at late gastrula, whereas offspring from the 8.7 mGy/h group was unaffected. Interestingly, one year after exposure newly derived embryos from the 8.7 mGy/h group exhibited 2390 (67.7% downregulated) differentially expressed genes. Overlaps in differentially expressed genes and enriched biological pathways were evident between the 53 mGy/h group one month and 8.7 mGy/h one year after exposure, but were oppositely regulated. Pathways could be linked to effects in adults and offspring, such as DNA damage (via Atm signaling) and reproduction (via Gnrh signaling). Comparison with gene expression analysis in directly exposed embryos indicate transferrin a and cytochrome P450 2x6 as possible biomarkers for radiation response in zebrafish. Our results indicate latent effects following ionizing radiation exposure from the lower dose in parents that can be transmitted to offspring and warrants monitoring effects over subsequent generations. [ABSTRACT FROM AUTHOR]

Abstract: Chilhuacle pepper (Capsicum annuum L.) seeds were exposed to gamma radiation (GR) doses (0, 10, 80 and 120 Gy), and plants were grown in hydroponics with different osmotic potentials (OP) (− 0.036, − 0.072, − 0.092, and − 0.108 MPa) in the nutrient solution. We measured the nutrient concentrations, pH and electrical conductivity (EC) in fruits at different time points after transplanting (70, 90 and 130 dat), and found the GR, nutrient solution OP and their interactions differentially affected N, P, K, Ca, and Mg concentrations, as well as pH and EC in chilhuacle peppers.Graphical abstract: [ABSTRACT FROM AUTHOR]

A set of measurements have been conducted to determine the levels activity of gamma-emitters present in infant formula. The study of different samples shows the presence of the following radionuclides: 226Ra, 232Th and 40K with respectively average activity of 0.52 ±  0.087, 0.51 ± 0.062, 371.98  ± 3.68 Bq/kg. The mean annual doses lead to 0.62 and 0.24 mSv/year whereas the total risk is about 7.91 × 10−6 and 5.32 × 10−6 respectively ≤ 1 year and 1–2 years old infants. The obtained results show that no significant radiation dose and no risk to the infants due to consumption of these milks. [ABSTRACT FROM AUTHOR]

Objectives: The objective of this study was to explore the effect of gamma irradiation on the haematological and biochemical parameters of the allogeneic red blood cells units at different storage duration. Methods: A prospective comparative study was conducted at the Blood Bank unit, Department of Diagnostic Laboratory Services of Universiti Kebangsaan Malaysia Medical Centre (UKMMC) in year 2013. Total 36 allogeneic red blood cell units were selected by simple random sampling method and divided into two groups, 18 units in each group based on the storage period into i) up to 14 days and ii) >14 days to expiry. Pre and post irradiation samples were taken immediately before and after irradiation of the units to analyse for the haematological parameters such as plasma Hb level, percent red cell haemolysis, haemoglobin per unit blood (Hb/unit), haematocrit (HCT), red cell indices such as mean corpuscular volume (MCV), mean corpuscular haemoglobin (MCH), mean corpuscular haemoglobin concentration (MCHC) and biochemical parameters such as plasma sodium (Na+), potassium (K+) and LDH levels. Data was collected and statistical analysis was done. Results: Statistically significant changes were observed between red cell units of up to 14 days and > 14 days old and pre irradiated samples in terms of plasma haemoglobin level, percent red cell haemolysis and plasma Na+, K+ and LDH levels. However, pre and post irradiation samples in each group of 14 days and >14 days showed significant changes in the plasma Hb and % haemolysis, Hb/unit, HCT, MCV and MCH in 14 days group while only in plasma Hb, MCV and MCH in >14 days group without any effect on plasma Na+, K+ and LDH levels in both group. Conclusion: Comparison at two different red cells storage groups i.e. period of up to 14 days and >14 days, showed significant changes in haematological and biochemical parameters. In the pre irradiation group this reflects the gradual storage changes over time even without going through the irradiation process. On the other hand, the changes between pre and post--irradiation for both the groups of storage showed significant haematological changes indicating irradiation itself also causes significant changes. In view of all these findings, we recommend to irradiate the allogeneic red cell units within 14 days of collection to reduce the adverse effects resulted from irradiation on the cellular products. [ABSTRACT FROM AUTHOR]

Crocin (CRO) and safranal (SAF) are bioactive constituents of saffron (dried stigma of Crocus sativus flower), an expensive spice with medicinal properties. Aqueous extract of saffron is known for its antigenotoxic effect against environmental genotoxins/carcinogens. However, there is need to identify saffron constituents responsible for this antigenotoxic effect. The aim of our investigation was to ascertain the role of CRO and SAF as inhibitors of in vivo genotoxic stress. For this purpose, Swiss albino mice were pretreated with CRO (50-mg/kg body weight (bw))/SAF (0.025- and 0.25-ml/kg bw) by gavage for 2 days. Thereafter, the pretreated mice were exposed to the genotoxic agents: (1) gamma radiation (GR; 2 Gy), (2) urethane (URE; 800 mg/kg) and (3) procarbazine (PCB; 60 mg/kg). In addition, CRO (50 mg/kg) was co-administered with the nitrosation reaction mixture of methylurea (MU; 300-mg/kg bw) + sodium nitrite (15 mg/kg) which can form N-nitroso-N-MU in the stomach. Genotoxic damage was measured by performing the bone marrow micronucleus test. Results obtained demonstrated significant reductions in the incidence of micronucleated polychromatic erythrocytes in the bone marrow of mice pretreated with CRO/SAF before exposure to the above DNA damaging agents, GR, URE and PCB. Co-administration of CRO with the nitrosation reaction mixture led to significant decrease in genotoxicity when compared to nitrosation reaction mixture alone. Histopathological studies revealed that these saffron constituents reduced testicular cell damage induced by the test genotoxins. The cell-free DNA-nicking assay using pBR322 DNA showed significant protective effects of CRO against hydroxyl radical-induced strand breaks. [ABSTRACT FROM AUTHOR]

The study was undertaken to evaluate gamma radiation-induced DNA damage in Aedes aegypti. The comet assay was employed to demonstrate the extent of DNA damage produced in adult male A. aegypti exposed to seven different doses of gamma radiation, ranging from 1 Gy to 50 Gy. DNA damage was measured as the percentage of comet tail DNA. A significant linear increase in DNA damage was observed in all samples; the extent of damage being proportional to the dose of gamma radiation the organism received, except in those treated with 1 Gy. The highest amount of DNA damage was noticed at 1 h postirradiation, which decreased gradually with time, that is, at 3, 6 and 12 h postirradiation. This may indicate repair of the damaged DNA and/or loss of heavily damaged cells as the postirradiation time increased. The comet assay serves as a sensitive and rapid technique to detect gamma radiation-induced DNA damage in A. aegypti. This could be used as a potential biomarker for environmental risk assessment. [ABSTRACT FROM AUTHOR]

The objective of this study was to determine the contribution of corn kernel enzymes, bacteria, fungi, and fermentation end-products (main acids and ethanol) to protein solubilization during fermentation of reconstituted corn grain silage. Flint corn kernels were ground (5-mm sieve), rehydrated to 32% of moisture, and treated with no additives (control), gamma irradiation (32 kGy), gamma irradiation + fermentation end-products (1% of lactic acid, 0.3% of acetic acid, and 0.7% of ethanol, as fed), and natamycin (1% as fed). Treated grains were ensiled in nylon-polyethylene bags and stored for 90 d. Protein solubilization was calculated for each treatment and the contributions of proteolytic sources were determined. Bacterial activity was the main contributor to proteolysis (60%) followed by corn kernel enzymes (30%), whereas fungi and fermentation end-products had only minor contributions (~5% each). [ABSTRACT FROM AUTHOR]

Gamma radiation represents a potential health risk to aquatic and terrestrial biota, due to its ability to ionize atoms and molecules in living tissues. The effects of exposure to 60 Co gamma radiation in zebrafish ( Danio rerio ) were studied during two sensitive life stages: gametogenesis (F0: 53 and 8.7 mGy/h for 27 days, total doses 31 and 5.2 Gy) and embryogenesis (9.6 mGy/h for 65 h; total dose 0.62 Gy). Progeny of F0 exposed to 53 mGy/h showed 100% mortality occurring at the gastrulation stage corresponding to 8 h post fertilization (hpf). Control and F0 fish exposed to 8.7 mGy/h were used to create four lines in the first filial generation (F1): control, G line (irradiated during parental gametogenesis), E line (irradiated during embryogenesis) and GE line (irradiated during parental gametogenesis and embryogenesis). A statistically significant cumulative mortality of GE larva (9.3%) compared to controls was found at 96 hpf. E line embryos hatched significantly earlier compared to controls, G and GE (48–72 hpf). The deformity frequency was higher in G and GE, but not E line compared to controls at 72 hpf. One month after parental irradiation, the formation of reactive oxygen species (ROS) was increased in the G line, but did not significantly differ from controls one year after parental irradiation, while at the same time point it was significantly increased in the directly exposed E and GE lines from 60 to 120 hpf. Lipid peroxidation (LPO) was significantly increased in the G line one year after parental irradiation, while significant increase in DNA damage was detected in both the G and GE compared to controls and E line at 72 hpf. Radiation-induced bystander effects, triggered by culture media from tissue explants and observed as influx of Ca 2+ ions through the cellular membrane of the reporter cells, were significantly increased in 72 hpf G line progeny one month after irradiation of the parents. One year after parental irradiation, the bystander effects were increased in the E line compared to controls, but not in progeny of irradiated parents (G and GE lines). Overall, this study showed that irradiation of parents can result in multigenerational oxidative stress and genomic instability in irradiated (GE) and non-irradiated (G) progeny of irradiated parents, including increases in ROS formation, LPO, DNA damage and bystander effects. The results therefore highlight the necessity for multi- and transgenerational studies to assess the environmental impact of gamma radiation. [ABSTRACT FROM AUTHOR]

Exposure to either lead (Pb) or γ-irradiation (IR) results in oxidative stress in biological systems. Herein, we explored the potential anti-apoptotic effect of spermine (Spm) against lead and/or γ-irradiation-induced hepatotoxicity in male albino rats. Rats were divided into eight experimental groups of ten rats each: groups including negative control, whole body γ-irradiated (6 Gray (Gy)), lead acetate (PbAct) trihydrate orally administered (75 mg/kg bw ≡ 40 mg/kg bw Pb for 14 consecutive days), and Spm intraperitoneally dosed (10 mg/kg bw for 14 consecutive days) rats and groups subjected to combinations of Pb + IR, Spm + IR, Spm + Pb, and Spm + Pb followed by IR on day 14 (Spm + Pb + IR). A significant decrease in arginase activity as well as mRNA and protein levels of Bcl-2 and p21 was observed in rats intoxicated with Pb and/or γ-irradiation compared to controls, whereas Bax mRNA and protein levels were significantly increased. Also, an increased level of nitric oxide (NO) with a reduced arginase activity was observed in liver tissues of intoxicated rats. Spm co-treatment with lead and/or γ-irradiation attenuated the increase in Bax mRNA and protein expression, while it restored those of Bcl-2 and p21 together with NO levels and arginase activity to control values. Altogether, we suggest that Spm may be useful in combating free radical-induced apoptosis in Pb-intoxicated and/or γ-irradiated rats. [ABSTRACT FROM AUTHOR]

The effect of radiation on the aquatic environment is of major concern in recent years. Limited data is available on the genotoxicity of gamma radiation on different tissues of aquatic organisms. Hence, the present investigation was carried out to study the DNA damage induced by gamma radiation in the gill and muscle tissues and their relative sensitivity using the comet assay in the freshwater teleost fish, common carp ( Cyprinus carpio ). The comet assay was optimized and validated in common carp using cyclophosphamide (CP), a reference genotoxic agent. The fish were exposed (acute) to various doses of gamma radiation (2, 4, 6, 8 and 10 Gy) and samplings (gill and muscle tissue) were done at regular intervals (24, 48 and 72 h) to assess the DNA damage. A significant increase in DNA damage was observed as indicated by an increase in % tail DNA for all doses of gamma radiation in both tissues. We also observed a dose-related increase and a time-dependent decrease of DNA damage. In comparison, DNA damage showed different sensitivity among the tissues at different doses. This shows that a particular dose may have different effects on different tissues which could be due to physiological factors of the particular tissue. Our study also suggests that the gills and muscle of fish are sensitive and reliable tissues for evaluating the genotoxic effects of reference and environmental agents, using the comet assay. [ABSTRACT FROM AUTHOR]

Hemorrhage following whole-body γ-irradiation in a combined injury (CI) model increases mortality compared to whole-body γ-irradiation alone (RI). The decreased survival in CI is accompanied by increased bone marrow injury, decreased hematocrit, and alterations of miRNA in the kidney. In this study, our aim was to examine cytokine homeostasis, susceptibility to systemic bacterial infection, and intestinal injury. More specifically, we evaluated the interleukin-6 (IL-6)-induced stress proteins including C-reactive protein (CRP), complement 3 (C3), Flt-3 ligand, and corticosterone. CD2F1 male mice received 8.75 Gy 60Co gamma photons (0.6 Gy/min, bilateral) which was followed by a hemorrhage of 20% of the blood volume. In serum, RI caused an increase of IL-1, IL-2, IL-3, IL-5, IL-6, IL-12, IL-13, IL-15, IL-17A, IL-18, G-CSF, CM-CSF, eotaxin, IFN-γ, MCP-1, MIP, RANTES, and TNF-α, which were all increased by hemorrhage alone, except IL-9, IL-17A, and MCP-1. Nevertheless, CI further elevated RI-induced increases of these cytokines except for G-CSF, IFN- γ and RANTES in serum. In the ileum, hemorrhage in the CI model significantly enhanced RI-induced IL-1β, IL-3, IL-6, IL-10, IL-12p70, IL-13, IL-18, and TNF-α concentrations. In addition, Proteus mirabilis Gram(-) was found in only 1 of 6 surviving RI mice on Day 15, whereas Streptococcus sanguinis Gram(+) and Sphingomonas paucimobilis Gram(-) were detected in 2 of 3 surviving CI mice (with 3 CI mice diseased due to inflammation and infection before day 15) at the same time point. Hemorrhage in the CI model enhanced the RI-induced increases in C3 and decreases in CRP concentrations. However, hemorrhage alone did not alter the basal levels, but hemorrhage in the CI model displayed similar increases in Flt-3 ligand levels as RI did. Hemorrhage alone altered the basal levels of corticosterone early after injury, which then returned to the baseline, but in RI mice and CI mice the increased corticosterone concentration remained elevated throughout the 15 day study. CI increased 8 miRNAs and decreased 10 miRNAs in serum, and increased 16 miRNA and decreased 6 miRNAs in ileum tissue. Among the altered miRNAs, CI increased miR-34 in the serum and ileum which targeted an increased phosphorylation of ERK, p38, and increased NF-κB, thereby leading to increased iNOS expression and activation of caspase-3 in the ileum. Further, let-7g/miR-98 targeted the increased phosphorylation of STAT3 in the ileum, which is known to bind to the iNOS gene. These changes may correlate with cell death in the ileum of CI mice. The histopathology displayed blunted villi and villus edema in RI and CI mice. Based on the in silico analysis, miR-15, miR-99, and miR-100 were predicted to regulate IL-6 and TNF. These results suggest that CI-induced alterations of cytokines/chemokines, CRP, and C3 cause a homeostatic imbalance and may contribute to the pathophysiology of the gastrointestinal injury. Inhibitory intervention in these responses may prove therapeutic for CI and improve recovery of the ileal morphologic damage. [ABSTRACT FROM AUTHOR]

The biological effects of low-dose or low-dose-rate ionizing radiation on normal tissues has attracted attention. Based on previous research, we observed the morphology of liver tissues of C57BL/6J mice that received <50, 50–500, and 500–1000 μGy/h of 137Cs radiation for 180 d. We found that the pathological changes in liver tissues were more obvious as the irradiation dose rates increased. Additionally, differential protein expression in liver tissues was analyzed using a proteomics approach. Compared with the matched group in the 2D gel analysis of the irradiated groups, 69 proteins had ≥ 1.5-fold changes in expression. Twenty-three proteins were selected based on ≥2.5-fold change in expression, and 22 of them were meaningful for bioinformatics and protein fingerprinting analysis. These molecules were relevant to cytoskeleton processes, cell metabolism, biological defense, mitochondrial damage, detoxification and tumorigenesis. The results from real-time PCR and western blot (WB) analyses showed that calreticulin (CRT) was up-regulated in the irradiated groups, which indicates that CRT may be relevant to stress reactions when mouse livers are exposed to low-dose irradiation and that low-dose-rate ionizing radiation may pose a cancer risk. The CRT protein can be a potential candidate for low-dose or low-dose-rate ionizing radiation early-warning biomarkers. However, the underlying mechanism requires further investigation. [ABSTRACT FROM AUTHOR]

In the present research effects of gamma irradiation (5–20 kGy) on the physicochemical, antioxidant and thermal properties of brown rice starch were studied. Scanning electron microscopy displayed mostly polyhedral shapes with no surface fractures. XRD displayed characteristic A type pattern and decrease in per cent crystallinity (22.53–20.41%) was observed as the dose increased from 5 to 20 kGy. DPPH % inhibition and FRAP values were increased in a dose dependent manner. Pasting properties (peak, final and setback viscosity) decreased with irradiation. Pasting temperature also significantly decreased with irradiation for all the irradiated starches. The transition temperatures, enthalpy of gelatinization, pH and apparent amylose content of starch decreased significantly with increase in irradiation dose. [ABSTRACT FROM AUTHOR]

Purpose:This review evaluates the effects of γ-rays on the regeneration of murine hair follicles in the natural hair cycle. A series of studies were performed to investigate this issue, in which the whole bodies of C57BL/10JHir mice in the 1st telogen phase of the hair cycle were irradiated with γ-rays. Results:The dermis of the irradiated skin showed a decrease in hair follicle density and induction of curved hair follicles along with the presence of white hairs and hypopigmented hair bulbs in the 2nd and 3rd anagen phases. An increased frequency of hypopigmented hair bulbs was still observed in the later hair cycle at postnatal day 200. There was no significant difference in the number of stem cells in the hair bulge region between control and irradiated skin. Conclusions:These results show that the effects of γ-rays on the pigmentation of murine hair follicles are persistently carried over to later hair cycles, although those on the number and structure of hair follicles appear to be hidden by the effects of aging. Our findings may be important for understanding the mechanisms of the actions of stem cells on hair regeneration in connection with age-related phenotypes. [ABSTRACT FROM PUBLISHER]

Ethylene propylene diene terpolymer (EPDM) rubber nanocomposites have been prepared by incorporating 10 phr of organically modified montmorillonite (OMMT) nanoclay and various percentages of fumed silica (10, 20, and 30 phr) onto EPDM rubber composite using two roll mill and crosslinked by gamma radiation. The effect of radiation dose on the mechanical properties namely tensile strength and elongation at break and the physical properties namely solubility and swelling were investigated. Thermogravimetric analysis was carried out to analyses the thermal stability of the nanocomposites. Volume resistivity of the nanocomposites was also measured. The results showed that the mechanical, volume resistivity, and thermal properties of the irradiated EPDM rubber containing OMMT were increased by adding of the fumed silica. The effect of N,N-m-phenylenedimaleimide coagent on the mentioned properties of the EPDM rubber nanocomposites was studied. The results showed that the physical, mechanical, and thermal properties of the irradiated EPDM rubber nanocomposites improved with the addition of the coagent due to the increase of the crosslinking density. The inclusion of both the 30 phr fumed silica and the coagent in the nanocomposite irradiated to 50 kGy leads to a synergistic effect. J. VINYL ADDIT. TECHNOL., 23:E188-E200, 2017. © 2016 Society of Plastics Engineers [ABSTRACT FROM AUTHOR]

Neuronal activity is characterized by a diversity of oscillatory phenomena that are associated with multiple behavioral and cognitive processes, yet the functional consequences of these oscillations are not fully understood. Our aim was to determine whether and how these different oscillatory activities affect short-term synaptic plasticity (STP), using the olfactory system as a model. In response to odorant stimuli, the olfactory bulb displays a slow breathing rhythm as well as beta and gamma oscillations. Since the firing of olfactory bulb projecting neurons is phase-locked with beta and gamma oscillations, structures downstream from the olfactory bulb should be driven preferentially at these frequencies. We examined STP exhibited by olfactory bulb inputs in slices of adult mouse piriform cortex maintained in vitro in an in vivo-like ACSF (calcium concentration: 1.1 mM). We replaced the presynaptic neuronal firing rate by repeated electrical stimulation (frequency between 3.125 and 100 Hz) applied to the lateral olfactory tract. Our results revealed a considerable enhancement of postsynaptic response amplitude for stimulation frequencies in the beta and gamma range. A phenomenological model of STP fitted to the data suggests that the experimental results can be explained by the interplay between three mechanisms: a short-term facilitation mechanism (time constant ≈160 msec), and two short-term depression mechanisms (recovery time constants <20 msec and ≈140 msec). Increasing calcium concentration (2.2 mM) resulted in an increase in the time constant of facilitation and in a strengthening of the slowest depression mechanism. As a result, response enhancement was reduced and its peak shifted toward the low beta and alpha ranges while depression became predominant in the gamma band. Using environmental conditions corresponding to those that prevail in vivo, our study shows that STP in the lateral olfactory tract to layer Ia synapse allows amplification of olfactory bulb inputs at beta and gamma frequencies. [ABSTRACT FROM AUTHOR]

Purpose:To explore the synergistic effect of a seleno-organic compound Ebselen (Ebs) and/or γ-radiation to exert antitumor effects on human breast cancer (MCF-7) cell line in vitro. Materials and methods:Ebs cytotoxicity at various concentrations (10, 25, 50 and 75 μg), cell proliferation and clonogenic assay of Ebs and/or γ-radiation (at 1, 3 and 6 Gy), expression of p-IκBα and NF-κB, inflammatory cytokines levels (TNF-α, IL-2, INF-γ, IL-10 and TGF-β), apoptotic factors (Caspase-3, Granzyme-B and TRAIL) and angiogenic factor (VEGF) were investigated. Results:The results showed that the effective dosage of this combination was observed at 25 μg/ml of Ebs with γ-radiation at 6 Gy. Data displayed a significant reduction in NF-κB mRNA along with an elevation in granzyme-B mRNA and TRAIL mRNA expression. Furthermore, protein expression of caspase-3 was elevated, whereas p-IκBα and p-NF-κB(p65) protein expression was reduced significantly. Also, a significant decline in TNF-α, IL-2, INF-γ, TGF-β with a significant increase in IL-10 levels were revealed. Meanwhile, a significant decrease in VEGF level and proliferation capacity were observed. Conclusions:We conclude that a combination of Ebs with radiotherapy has a major antitumor efficiency in inducing apoptosis and inhibiting cancer cell progression, due to the synergistic effect in regulating gene and protein expression, and in a modulating response of pro-and anti-inflammatory cytokines. [ABSTRACT FROM AUTHOR]

Cultivation of okra in Ghana is challenged by low yield due to lack of improved varieties. Gamma irradiated okra seeds can generate genetic variability to improve the crop. Samples of 150 seeds, each of okra genotype, UCCC6, were irradiated with 400 Gy to 1000 Gy using cobalt 60 source at a dose rate exposure of 121.58 Gy/hr. There were 40 stands comprising single plant per stand in three replications per treatment in a randomized complete block design outlay. Seedling survival, plant height, number of leaves, stem diameter, number of branches, leaf length and width, days to 50% flowering, number of fruits, length and weight of fruit, number of seeds, and 100-seed weight decreased significantly (P≤0.05) with increasing doses of gamma rays. Seedling survival was highest (88%) at 400 Gy, followed by control (81%). However, 600 Gy, 800 Gy, and 1000 Gy had 61%, 41%, and 17% seedling survival, respectively, with LD50 at 720 Gy. Significant (P≤0.05) correlations existed between growth and yield components. Optimum growth and yield in okra were induced by 400 Gy but the higher doses had growth retardation effects and the induced variability can be assessed at M2 generation. [ABSTRACT FROM AUTHOR]

The purpose of this study was to evaluate the performance and refine the design of the collimation system for the gamma radiation source (GBS) currently being realised at ELI-NP facility. The gamma beam, produced by inverse Compton scattering, will provide a tunable average energy in the range between 0.2 and 20 MeV, an energy bandwidth 0.5% and a flux of about 10 8 photons/s. As a result of the inverse Compton interaction, the energy of the emitted radiation is related to the emission angle, it is maximum in the backscattering direction and decreases as the angle increase [1,2] . Therefore, the required energy bandwidth can be obtained only by developing a specific collimation system of the gamma beam, i.e. filtering out the radiation emitted at larger angles. The angular acceptance of the collimation for ELI-NP-GBS must be continuously adjustable in a range from about 700 to 60 μrad, to obtain the required parameters in the entire energy range. The solution identified is a stack of adjustable slits, arranged with a relative rotation around the beam axis to obtain an hole with an approximately circular shape. In this contribution, the final collimation design and its performance evaluated by carrying out a series of detailed Geant4 simulations both of the high-energy and the low-energy beamline are presented. [ABSTRACT FROM AUTHOR]

Gum tragacanth (GT) exuding from an IranianAstragalusspecies was γ-irradiated at 0, 0.75, 1.5, 3, 5, 7, and 10 kGy and used to stabilize a model oil-in-water emulsion system. Stability and physicochemical properties of emulsion samples were investigated with respect to the effect of irradiation treatment on functional properties of gum tragacanth. Particle size distribution, interfacial tension, zeta potential, steady shear, and oscillatory rheological measurements were used to characterize and evaluate the emulsion samples and obtain more information about the possible stability mechanism. Emulsions were prepared by homogenizing 10% w/w sun flower oil with 90% w/w aqueous gum dispersions and stored quiescently at 25°C for 120 days. The results indicated that using 1.5 kGy irradiated GT was more effective in providing optimum values of apparent viscosity, number mean diameter, electrosteric repulsion, and structure strength for getting the maximum emulsion stability. GT significantly reduced the interfacial tension of the oil and water system, but no significant differences were observed among all irradiation treated and non-irradiated samples. This study revealed that GT acts as a bifunctional emulsifier and irradiation treatment has a great positive influence on its ability to reduce droplets’ collision frequency and stabilize the oil-in-water emulsion. [ABSTRACT FROM PUBLISHER]

In this study, the B6CF1mice from the JANUS program at the Argonne National Laboratory were analyzed for increased cardiovascular disease (CVD) mortality from60Co γ ray or fission neutron exposures administered in either a single dose or protracted weekly doses. The data used for this study represent the last studies conducted at Argonne and have been archived for at least 15 years. CVD mortality increased in a dose-dependent manner from γ rays as well as from neutron exposures. The relative biological effectiveness (RBE) for neutrons is about 4 or 5. CVD mortality appeared to be enhanced when the dose was protracted, with a DDREF (dose and dose rate effectiveness factor) in the range of 0.4–0.45 for neutron and gamma ray exposure, respectively. [ABSTRACT FROM PUBLISHER]

Particle induced gamma-ray emission (PIGE) method using 4 MeV proton beam was utilized to analyze two types of barium borosilicate glass (BaBSG) samples for quantification of concentrations of low Z elements. The in situ current normalization method was applied in the analysis of eight samples containing varying concentration of F along with Si, B and Na. Charge normalized PIGE method was applied to determine concentrations of above low Z elements including Li and Al in samples having simulated nuclear waste from reprocessing of thoria spent fuel. Synthetic samples and NIST SRMs were used for method validation. [ABSTRACT FROM AUTHOR]

The gamma degradation of toxic non-oxidizing biocide dodecyl dimethyl benzyl ammonium chloride (DDBAC) was investigated. The degradation of DDBAC achieved 70-100% depending on the initial concentration and the absorbed dose, but only 10-33% dissolved organic carbon was removed. The presence of NO , HCO , 2-propanol and tert-butanol inhibited the degradation of DDBAC. The DDBAC degradation rate constant ratios of ·OH, ·H and e was calculated as 7.4:1.4:1. The acute toxicity of 10 mg L DDBAC was removed by 60% at absorbed doses of 0.5-3.0 kGy. The results showed that gamma irradiation was effective to remove DDBAC and its toxicity. [ABSTRACT FROM AUTHOR]

This study explores the possibility for protection by curcumin during the molecular and structural changes of human serum albumin (HSA) exposed to gamma irradiation. We used a combination of spectroscopic methods to probe the conformational ensemble of the irradiated HSA and finally evaluated the extent of restoration by curcumin. SDS-PAGE study unfolded the formation of cross linked aggregates as a consequence of increasing exposure of gamma radiation. CD and FTIR spectroscopy indicated significant decrease in the alpha helix content of HSA from 57% to 15% with increasing radiation doses. Steady state and time resolved fluorescence studies complemented the spectroscopic measurements, when lifetime decay was significantly reduced from 6.35 ns to 0.37 ns. Hydrophobic study showed the effectiveness of curcumin for protection at low dose of gamma irradiated HSA samples. We integrated these observations to investigate protein aggregation under increasing gamma radiation and estimated the same in presence of curcumin. It was elucidated, that when HSA is irradiated at low dose of gamma radiation in presence of curcumin, it is capable of retaining the characteristic properties to a higher extent indicating stabilization of molecular structure of HSA by curcumin. A model for curcumin based protection has been proposed utilizing ThT assay. [ABSTRACT FROM AUTHOR]

Purpose:To investigate alterations of mitochondria in irradiated endothelial cells to further elucidate the mechanism underlying radiation-induced heart disease. Materials and methods:Experiments were performed using human umbilical vein endothelial cells (HUVECs). HUVECs were irradiated with single gamma ray dose of 0, 5, 10 and 20 Gy, respectively. Apoptosis was assessed by flow cytometry at 24, 48 and 72 h post-irradiation, respectively. The intracellular reactive oxygen species (ROS) was measured with 2′,7′-dichlorofluorescein-diacetate (DCFH-DA) at 24 h post-irradiation. Mitochondrial membrane potential (ΔΨm) by JC-1 and the opening of mitochondrial permeability transition pore (mPTP) by a calcein-cobalt quenching method were detected at 24 h post-irradiation in order to measure changes of mitochondria induced by gamma ray irradiation. Results:Gamma ray irradiation increased HUVECs apoptosis in a dose-dependent and time-dependent manner. Irradiation also promoted ROS production in HUVECs in a dose-dependent manner. At 24 h post-irradiation, the results showed that irradiation decreasesΔΨm, however, paradoxically, flow cytometry showed green fluorescence instensity higher in irradiated HUVECs than in control HUVECs in an irradiation dose-dependent manner which indicated gamma ray irradiation inhibited mPTP opening in HUVECs. Conclusions:Gamma ray irradiation induces apoptosis and ROS production of endothelial cells, and decreasesΔΨm meanwhile contradictorily inhibiting the opening of mPTP. [ABSTRACT FROM AUTHOR]

The effect of two substerilizing doses of gamma radiation (80 and 160 Gy) and/or emamectin benzoate at different concentrations and the LC50 value on the greater wax moth Galleria mellonella L. larvae was studied. The amount of food consumed at the different treatments was also evaluated. Obtained results indicated that the maximum mortality percentage recorded was (95.87%) corresponding to 50 ppm of emamectin benzoate. The combined treatment of LC50 and 160Gy increased the larval mortality percentage to reach (95.7%), i.e. this combined treatment had a greater effect against G. mellonella than the application of each one alone. The results indicated that antifeedant activity increased by increasing the combined gamma radiation dose where the maximum antifeedant percentage (84.79%) was corresponding to the treatment of LC50+160Gy. This antifeedant activity may be due to the effect of these treatments on larval mouth parts and its associated sensilla, so an ultrastructure study of mouth parts and its sensitivity was done using a scanning electron microscope (SEM.). The SEM study revealed that different malformations or abnormalities were observed in mouth labium, labrum, mandible and maxillae in the form of shrinkage in these parts, malformation at its edge and even malformation in shape. Also, the mouth parts associated sensilla were malformed and these malformation features were correlated with gamma dose applied. These malformations ranged from twisted, bent, impaired, shrinkage, grooved base or falling of sensilla, leaving their position empty and the area became bare. These different abnormalities or malformations to mouth parts and their sensilla will indirectly lead to larval death as they fail to ingest food. [ABSTRACT FROM AUTHOR]

The study addresses biological effects of low-dose gamma-radiation. Radioactive 137 Cs-containing particles were used as model sources of gamma-radiation. Luminous marine bacterium Photobacterium phosphoreum was used as a bioassay with the bioluminescent intensity as the physiological parameter tested. To investigate the sensitivity of the bacteria to the low-dose gamma-radiation exposure (≤250 mGy), the irradiation conditions were varied as follows: bioluminescence intensity was measured at 5, 10, and 20°С for 175, 100, and 47 h, respectively, at different dose rates (up to 4100 μGy/h). There was no noticeable effect of gamma-radiation at 5 and 10°С, while the 20°С exposure revealed authentic bioluminescence inhibition. The 20°С results of gamma-radiation exposure were compared to those for low-dose alpha- and beta-radiation exposures studied previously under comparable experimental conditions. In contrast to ionizing radiation of alpha and beta types, gamma-emission did not initiate bacterial bioluminescence activation (adaptive response). As with alpha- and beta-radiation, gamma-emission did not demonstrate monotonic dose-effect dependencies; the bioluminescence inhibition efficiency was found to be related to the exposure time, while no dose rate dependence was found. The sequence analysis of 16S ribosomal RNA gene did not reveal a mutagenic effect of low-dose gamma radiation. The exposure time that caused 50% bioluminescence inhibition was suggested as a test parameter for radiotoxicity evaluation under conditions of chronic low-dose gamma irradiation. [ABSTRACT FROM AUTHOR]

BACKGROUND Little has been reported about the effects of gamma radiation on the physical and sensory characteristics of rice. Samples were irradiated with 60Co in doses 0, 1, 2 and 5 kGy, on a rate of 0.4 kGy h−1. RESULTS The evaluation of instrumental color showed that increasing doses promoted the yellowing (higher b* value) of the rice grains. Hardness was decreased and stickiness was increased in cooked rice with increasing doses. Sensory evaluation using quantitative descriptive analysis showed that increasing doses promoted higher occurrence of yellowish appearance, emergence of burnt aroma, and an increase of bitter and burnt taste. The sensory acceptance test by 9-point hedonic scale showed alteration of the samples irradiated with 5 kGy in all evaluated attributes (appearance, color, aroma, taste and texture). The lowest dose (1 kGy), however, had good acceptability by the panelists. CONCLUSION Rice may be subjected to 1 kGy dose of gamma radiation without changes or with small changes in physical properties and with good overall acceptability. © 2016 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

Health risks from space radiations, particularly from densely ionizing radiations, represent an important challenge for long-ranged manned space missions. Reliable methods are needed for scaling low-LET to high-LET radiation risks for humans, based on animal or in vitro studies comparing these radiations. The current standard metric, relative biological effectiveness (RBE) compares iso-effect doses of two radiations. By contrast, a proposed new metric, radiation effects ratio (RER), compares effects of two radiations at the same dose. This definition of RER allows direct scaling of low-LET to high-LET radiation risks in humans at the dose or doses of interest. By contrast to RBE, RER can be used without need for detailed information about dose response shapes for compared radiations. This property of RER allows animal carcinogenesis experiments to be simplified by reducing the number of tested radiation doses. For simple linear dose-effect relationships, RBE = RER. However, for more complex dose-effect relationships, such as those with nontargeted effects at low doses, RER can be lower than RBE. We estimated RBE and RER values and uncertainties using heavy ion (12C, 28Si, 56Fe) and gamma-ray-induced tumors in a mouse model for intestinal cancer (APC1638N/+), and used both RBE and RER to estimate low-LET to high-LET risk scaling factors. The data showed clear evidence of nontargeted effects at low doses. In situations, such as the ones discussed here where nontargeted effects dominate at low doses, RER was lower than RBE by factors around 2.8-3.5 at 0.03 Gy and 1.3-1.4 at 0.3 Gy. It follows that low-dose high-LET human cancer risks scaled from low-LET human risks using RBE may be correspondingly overestimated. [ABSTRACT FROM AUTHOR]

St. Augustinegrass [Stenotaphrum secundatum (Walt.) Kuntze] is a warm-season turfgrass with medium to high shade tolerance, a valuable trait for use in lawns, particularly in smaller residential landscapes and other green spaces where trees are dominant. However, their long internodes and very coarse leaf and stolon texture are undesirable in home lawns and public spaces. Gamma (γ) irradiation has been used to induce useful variations for various morphological traits in turfgrass breeding. The objective of the present study was to induce dwarf and semidwarf phenotypes from two St. Augustine germplasms, S1 and S2, irradiated with 50, 100, 150, or 300 Gy and 20, 40, 80 or 120 Gy respectively, using a 60Co source. The lethal does (LD50) for S1 and S2 genotypes were 95 and 103 Gy, respectively. The linear reduction of survival rate with increasing gamma rays was highly correlated (r2 = 0.96 and 0.87). The 15 morphological mutants (0.35% of the irradiated plants) with a semidwarfed growth habits were identified among 4301 node cuttings. The mutant lines exhibited up to 40% shorter plant height and finer leaf and stolon texture than parental genotypes. Mutant lines developed in this study may offer improved St. Augustinegrass cultivars for landscaping. [ABSTRACT FROM AUTHOR]

Purpose:To evaluate the efficacy of persimmon leaf extract (PL (as a rich plant source) in modulation of radiation-induced liver injury and some metabolic variations in gamma-irradiated rats. Materials and methods:PL at a dose of 1000 mg/kg body weight (P1000) was administered to male albino rats via gastric intubation for 15 days after whole body γ-irradiation (6 Gy). Results:Irradiated rats showed significant decreases in hepatic glutathione content (GSH), superoxide dismutase (SOD), catalase (CAT) and xanthine dehydrogenase (XDH) activities with significant increases in malondialdehyde (MDA) level and xanthine oxidase (XO) activity designating oxidative stress. In parallel significant increases in serum aspartate and alanine transaminase (AST, ALT), alkaline phosphatase (ALP), γ-glutamyl-transferase (GGT) activities and bilirubin content were recorded indicating liver injury. In addition, hyperglycemia, hypoinsulinemia and dyslipidemia (elevated total cholesterol, triglycerides, low density lipoprotein-cholesterol and Atherogenic Index and decreased high density lipoprotein-cholesterol) were recorded. PL treatment has significantly attenuated radiation-induced oxidative stress in hepatic tissues concomitant with significant amelioration of liver function and metabolic disturbances. Conclusion:It is concluded that PL may have therapeutic potential to alleviate the severity of radiation-induced liver injury, hyperglycemia, hypoinsulinemia and dyslipidemia. [ABSTRACT FROM PUBLISHER]

To assess the therapeutic effects of the human umbilical cord blood (hUCB) derived mesenchymal stem cells (MSCs) on rat bone marrow (BM) exposed to gamma rays, 3 groups (n = 15 each) of adult male Wistar albino rats were utilized as follows: the 1 st group received PBS (control group), the 2nd group was exposed to gamma rays 1.04 Gy/min (R group) and the 3rd group exposed to same dose as RG and injected hUCB-MSCs. The BM of femurs was processed for histological and immunohistochemical staining with proliferating cell nuclear antigen antibody (PCNA), anti human CD105 and anti human CD34. Hb content, leukocytes and platelet counts were analyzed as well as fat cells and megakaryocytic counts. Also, the BM vascular spaces and the optical density of immunostaining for PCNA were analyzed. The leukocytes and platelet counts were significantly lower in the R (2.85 ± 235.8; P = 0.000 and 95.27 ± 3.01; P = 0.000 respectively) when compared with the control (10.40 ± 443.2; P = 0.000 and 430.18 ± 20.28; P = 0.000 respectively). The fat cell count was significantly higher in the R (36.55 ± 1.83; P = 0.000) than in control (7.64 ± 0.61; P = 0.000) and in R injected h-MSCs tissues (18.82 ± 2.03; P = 0.000). The megakaryocytic count was significantly higher in the R injected h-MSCs (5.36 ± 0.310; P = 0.000) than in control (2.82 ± 0.263; P = 0.000) and in the R BM (0.45 ± 0.157; P = 0.000). The vascular spaces were dilated and significantly increased in the R injected h-MSCs (50.10 ± 2.40; P = 0.000) than in control (33.36 ± 1.01; P = 0.000). The optical density of PCNA expression was significantly lower in R (0.18 ± 0.11; P = 0.005) than in control (0.41 ± 0.40; P = 0.005) and in R injected h-MSCs groups (0.30 ± 0.17; P = 0.005). The present study concluded that injection of hUCB-MSCs improves destructive effects of bone marrow induced by gamma radiation. Use of radio-protective agents during exposure is recommended. [ABSTRACT FROM AUTHOR]

Monte Carlo simulations have been performed to model the gamma ray emission and attenuation properties of common rocks. In geologic materials, 40 K, 238 U, and 232 Th are responsible for most gamma ray production. If the concentration of these radioelements and attenuation factors such as degree of water saturation are known, an estimate of the gamma-ray exposure rate can be made. The results show that there are no significant differences in gamma-ray screening between major rock types. If the total number of radionuclide atoms are held constant then the major controlling factor is density of the rock. Finally, the thickness of regolith or soil overlying rock can be estimated by modeling the exposure rate if the radionuclide contents of both materials are known. [ABSTRACT FROM AUTHOR]