Efecto radioprotector del ácido tánico y vinos de la var vitis vinífera L. cv tannat en Saccharomyces cerevisiae / Radioprotective effect of tannic acid and wines of the vitis vinifera L. cv tannat on Saccharomyces cerevisiae / Proteção contra radiação por vinho tinto var tannat e ácido tanico em Saccharomyces cerevisiae

El vino tinto variedad Vitis vinifera L. cv Tannat en los últimos años ha tomado relevancia por su alta concentración de polifenoles, esto le podría significar un rol protector sobre el genoma disminuyendo la formación de lesiones oxidativas. Los efectos a nivel celular de las radiaciones ionizantes en blancos como el ADN, componentes de cascadas de transducción de señales, resultan en lesiones letales, mutagénicas y recombinogénicas y en retardos en el ciclo celular. Se utilizó como modelo eucariota poblaciones de Saccharomyces cerevisiae en fase exponencial expuestas a radiación gamma (200 Gy) en presencia, o ausencia, de vino Tannat (10 % v/v) o de ácido tánico (60 µg/mL). Se estimaron las probabilidades de sobrevida y frecuencia mutagénica en distintas condiciones. Las muestras celulares expuestas a radiación ionizante presentaron una fracción de sobrevida de 0.21 ± 0.02 mientras que en las muestras irradiadas en presencia de vino Tannat o de ácido tánico la fracción de sobrevida fue de 0.33 ± 0.03 y 0.30 ± 0.03 respectivamente. Se observó en las poblaciones irradiadas un aumento significativo de la probabilidad de mutagénesis. En el caso de los tratamientos combinados se observó que la frecuencia mutagénica fue significativamente menor (gamma Tannat: 33%, gamma ácido tánico: 45% ). Estos resultados preliminares podrían indicar radioprotección moderada por parte de los compuestos estudiados, efecto que podría explicarse por las interacciones redox del ácido tánico y polifenoles contenidos en el vino con los radicales libres formados por las radiaciones ionizantes, además de la activación de vías de reparación genómica.

The red wine variety Vitis vinifera L. cv Tannat in recent years has gained relevance due to its high concentration of polyphenols, this could mean a protective role on the genome, reducing the formation of oxidative lesions. The effects at the cellular level of ionizing radiation on targets such as DNA, components of signal transduction cascades, result in lethal, mutagenic and recombinogenic lesions and delays in the cell cycle. Exponential phase populations of Saccharomyces cerevisiae exposed to gamma radiation (200 Gy) in the presence or absence of Tannat wine (10% v / v) or tannic acid (60 µg / ml) were used as a eukaryotic model. The probabilities of survival and mutagenic frequency in different conditions were estimated. Cellular samples exposed to ionizing radiation presented a survival fraction of 0.21 ± 0.02, while in samples irradiated in the presence of Tannat wine or tannic acid, the survival fraction was 0.33 ± 0.03 and 0.30 ± 0.03 respectively. A significant increase in the probability of mutagenesis was observed in irradiated populations. In the case of the combined treatments, it was observed that the mutagenic frequency was significantly lower (Tannat gamma: 33%, Tannic acid gamma: 45%). These preliminary results could indicate moderate radioprotection by the compounds studied, an effect that could be explained by the redox interactions of tannic acid and polyphenols contained in wine with the free radicals formed by ionizing radiation, in addition to the activation of genomic repair pathways.

A variedade de vinho tinto Vitis vinifera L. cv Tannat nos últimos anos tem ganhado relevância devido à sua alta concentração de polifenóis, o que pode significar um papel protetor do genoma, reduzindo a formação de lesões oxidativas. Os efeitos no nível celular da radiação ionizante em alvos como o DNA, componentes de cascatas de transdução de sinal, resultam em lesões letais, mutagênicas e recombinogênicas e atrasos no ciclo celular. Populações de fase exponencial de Saccharomyces cerevisiae expostas à radiação gama (200 Gy) na presença ou ausência de vinho Tannat (10% v / v) ou ácido tânico (60 µg / ml) foram utilizadas como modelo eucariótico. Foram estimadas as probabilidades de sobrevivência e frequência mutagênica em diferentes condições. As amostras celulares expostas à radiação ionizante apresentaram uma fração de sobrevivência de 0,21 ± 0,02, enquanto nas amostras irradiadas na presença de vinho Tannat ou ácido tânico, a fração de sobrevivência foi de 0,33 ± 0,03 e 0,30 ± 0,03, respectivamente. Um aumento significativo na probabilidade de mutagênese foi observado nas populações irradiadas. No caso dos tratamentos combinados, observou-se que a frequência mutagênica foi significativamente menor (Tannat gama: 33%, ácido tânico gama: 45%). Esses resultados preliminares podem indicar radioproteção moderada pelos compostos estudados, efeito que pode ser explicado pelas interações redox do ácido tânico e polifenóis contidos no vinho com os radicais livres formados pela radiação ionizante, além da ativação de vias de reparo genômico.

Efeito da radiação gama sobre a oxidação lipídica da carne bovina / Effect of gamma radiation on lipid oxidation of beef

Objetivou-se avaliar o efeito de diferentes doses de radiação (1, 2, 3, 6 e 9 kGy) sobre a oxidação lipídica de contrafilés bovinos pela determinação das substâncias reativas ao ácido 2-tiobarbitúrico (TBARS) e por cromatografia gasosa utilizando a técnica de microextração em fase sólida (SPME). As amostras irradiadas apresentaram maior concentração de aldeídos, com maior incidência de nonanal, independentemente da dose aplicada. Maiores concentrações de hexanal foram observadas nas amostras irradiadas por maiores doses (6 e 9 kGy), mas os maiores valores de TBARS foram observados nas amostras irradiadas por 3 e 6 kGy. Uma redução nos valores de aldeídos, especialmente nonanal e octanal, foi observada para amostras irradiadas por 2 kGy quando comparadas às demais amostras irradiadas. Conclui-se que o processo de irradiação aumentou o grau de oxidação das amostras, que consequentemente, aumentou a concentração dos aldeídos presentes.

Therapeutic effect of Aloe vera and silver nanoparticles on acid-induced oral ulcer in gamma-irradiated mice

Abstract Radiation combined injury, a life-threatening condition, has higher mortality than simple radiation injury. The aim of the present study was to analyze the efficiency of Aloe vera and silver nanoparticles in improving the healing of ulcerated oral mucosa after irradiation. Thirty male Albino mice were divided into five groups: control, radiation, Aloe vera (AV), silver nanoparticles (NS), and AV+NS. The mice were exposed to whole body 6Gy gamma-radiation. After one hour, 20% acetic acid was injected into the submucosal layer of the lower lip for ulcer induction. The animals received topical treatment with the assigned substances for 5 days. Lip specimens were subjected to hematoxylin and eosin and anti alpha-smooth muscle actin immunohistochemical staining. Results demonstrated occurance of ulcer three days post irradiation in all groups except in the AV+NS group where only epithelial detachment was developed. After seven days, data revealed persistent ulcer in radiation group, and almost normal epithelium in the AV+NS group. A significant reduction of epithelial thickness was detected in all groups at the third day as compared to control. At the seventh day, only the AV+NS group restored the epithelial thickness. Area percent of alpha-smooth muscle actin expression was significantly decreased in radiation group at the third day followed by significant increase at the seventh day. However, all treatment groups showed significant increase in alpha-smooth muscle actin at the third day, which decreased to normal level at the seventh day. Our study demonstrated the efficiency of Aloe vera and silver nanoparticles in enhancing ulcer healing after irradiation.

Role of bone marrow transplantation in reducing the dangerous effect of multi-walled carbon nanotubes or/and gamma rays on male rats

Aim of the work: this study evaluated the efficacy of bone marrow [BM] transplantation to protect male rats from dangerous effect of multi-walled carbon nanotubes [MWCNTs] or/and y-irradiation on the hematopoietic and lung tissues

Materials and methods: experimental animals were divided into 8 groups each consist of 6 male albino rats. Control group, BM-injected group, MWCNTs-injected group, 5Gy y-irradiated group, 5Gy y-irradiated+ MWCNTs-injected group, MWCNTs-injected+ BM-injected group, 5Gy y-irradiated+ BM-injected group and 5Gy of y-irradiated+ MWCNTs-injected + BM-injected group. All the treated animal groups were sacrificed after 28 days of the treatments. Blood components, MDA and GSH levels in the lung tissue were analyzed. The histopathological study in the lung tissue was also recorded

Results: exposure to MWCNTs or/and y-radiation induced a significant decrease in certain blood components [WBCs, RBCs, Hb content, HCT value and PLT count]

Furthermore, a significant elevation in MDA level and a significant decrease in GSH content were detected in the lung tissue

The histopathological changes after exposure of rats to MWCNTs recorded perivasculitis, atelectasis and interstitial pneumonia. Also, y-radiation represented more collapsed and thickened walls in the alveoli, thickened bronchiolar walls with partial epithelial lining and foci of pulmonary hemorrhage in the lung tissue. The effect of BM transplantation after MWCNTs or/and y-radiation ameliorated the values of blood components, MDA and GSH levels in the lung tissue. The improvement occurred by BM transplantation in rats treated with MWCNTs or/and exposed to y-radiation were also recorded. The lung tissue showed numerous alveoli with thin interalveolar septa, alveolar sacs and terminal bronchioles with highly folded mucosa

Conclusion: treatment with BM transplantation improved the most deleterious parameters obtained in the blood and lung tissue of MWCNTs exposed or/and y-irradiated rats

Therapeutic effects of an ethanolic olive leaves extract or bone marrow mesenchymal stem cells against liver injury induced by gamma radiation

Background: Ionizing radiation absorption causes immediate biochemical, sub cellular and cellular damage, while its morphological expression and organ dysfunction are often considerably delayed. This study was aimed to investigate the possible therapeutic effects of ethanolic olive leaves extract or bone marrow derived-mesenchymal stem cells [BM-MSCs] transplanted in the liver of rats exposed to gamma radiation. For this purpose, hematological and biochemical parameters were determined

Materials and methods: 50 adult male albino rats [Sprague dawely strain] were used in this study. They were divided into 5 groups [C group: Untreated control rats; R group: rats exposed to a single dose of gamma-radiation [6 Gy], OLE group: rats treated with olive leaves extract [15 mg /kg body weight / day for 30 days], R+OLE group: animals of this group were irradiated with 6Gy then treated with OLE [15 mg /kg body weight/ day] after 3 hours post irradiation for 30 days. and R+MSCs group: Mesenchymal stem cells-irradiated animals [MSCs +R]: animals of this group were irradiated with 6Gy then injected after 6hours post irradiation with [BM-MSCs] 3x10[6] cells/ml suspension through caudal vein. All these groups were subjected to hematological and biochemical investigations

Results: Hematological and liver function changes were shown in gamma irradiated rats, these changes included a significant depression in hematological parameters of blood such as [RBCs, Hb, Hct and WBCs] and a significant increase in liver parameters [ALT,AST and ALP] at different intervals of the experiment in comparison with the control group. These changes manifested good amelioration in the exposed groups by using either olive leaves extract [OLE] or bone marrow mesenchymal stem cells [BM-MSCs]

Conclusion: Ethanolic olive leaves extracts and mesenchymal stem cells have ameliorated hematological and biochemical parameters changes in liver of the irradiated group. Their actions may be due to their anti-inflammatory and antioxidant properties

Long-term correlation of the electrocorticogram as a bioindicator of brain exposure to ionizing radiation

Understanding the effects of radiation and its possible influence on the nervous system are of great clinical interest. However, there have been few electrophysiological studies on brain activity after exposure to ionizing radiation (IR). A new methodological approach regarding the assessment of the possible effects of IR on brain activity is the use of linear and nonlinear mathematical methods in the analysis of complex time series, such as brain oscillations measured using the electrocorticogram (ECoG). The objective of this study was to use linear and nonlinear mathematical methods as biomarkers of gamma radiation regarding cortical electrical activity. Adult Wistar rats were divided into 3 groups: 1 control and 2 irradiated groups, evaluated at 24 h (IR24) and 90 days (IR90) after exposure to 18 Gy of gamma radiation from a cobalt-60 radiotherapy source. The ECoG was analyzed using power spectrum methods for the calculation of the power of delta, theta, alpha and beta rhythms and by means of the α-exponent of the detrended fluctuation analysis (DFA). Using both mathematical methods it was possible to identify changes in the ECoG, and to identify significant changes in the pattern of the recording at 24 h after irradiation. Some of these changes were persistent at 90 days after exposure to IR. In particular, the theta wave using the two methods showed higher sensitivity than other waves, suggesting that it is a possible biomarker of exposure to IR.

Ameliorative effect of septilin, an ayurvedic preparation against γ-irradiation-induced oxidative stress and tissue injury in rats.

Ionizing radiation is known to induce multiple organ dysfunctions directly related to an increase of cellular oxidative stress, due to overproduction of reactive oxygen species (ROS). This study was aimed to investigate the effect of septilin (an ayurvedic poly-herbal formulation containing the principal herbs, namely Commiphora wightii, Trinospora cordifolia, Rubia cardifolia, Emblica officinalis, Saussurea lappa and Glycyrrhiza glabra) against whole body γ-irradiation-induced oxidative damage in hepatic and brain tissues in rats. Administration of septilin for 5 days (100 mg/kg) prior to radiation resulted in a significant increase in both superoxide dismutase (SOD) activity and total glutathione (GSH) level in hepatic and brain tissues, while serum high-density lipoprotein-cholesterol (HDL) was reduced by γ-irradiation. Also, septilin resulted in a significant decrease in NO(x), nitric oxide and malondialdehyde (MDA) levels in hepatic and brain tissues and a significant decrease in serum triglycerides, low-density lipoprotein-cholesterol (LDL) and total cholesterol levels and serum alanine aminotransferase (ALT), aspartate aminotransferase (AST) levels and alkaline phosphatase (ALP), γ-glutamyl transferase (GGT) activities, as well as serum tumor necrosis factor-alpha (TNF-α), compared to irradiated group. In conclusion, data obtained from this study indicated that septilin exhibited potential antioxidant activity and showed radioprotective effect against γ-radiation by preventing oxidative stress and scavenging free radicals.

Effect of cynara scolymus L. [artichoke] extraction on hyperlipidemic induced by gamma radiation in male rats

Excessive free radicals are caused by unnatural environmental influences such as air pollution, radiation, cigarette smoke, factories, pesticides, food contaminants and a myriad of other factor that are part of our modern life. Hypercholesterolaemia is directly associated with an increased risk of coronary heart disease [CHD]. Cynara scolymus L. [Artichoke] grows in Egypt and other countries. It is used as foods and has medicinal properties. Artichoke extracts have been shown to produce various pharmacological effects, such as the inhibition of cholesterol biosynthesis and low density lipoprotein [LDL] oxidation. The present study aims to evaluate the antioxidative activities and radioprotector role of cynara scolymus L. [artichoke] against hyperlipidemic induced by gamma- irradiation in male rats. Male Swiss albino rats were orally administrated by artichoke [head or leaves] [10% mg/rat/day] using suitable stomach tube [6weeks, 45 days] before exposure to a single dose [6.5 Gy] of whole body gamma radiation. Levels of lipids peroxides [MDA], reduced glutathione content [GSH], superoxide dismutase [SOD], total cholesterol [TC], triacylglycerol [TG], high density lipoprotein [HDL-C] and low density lipoprotein [LDL-C] were investigated in serum. The results revealed that gamma radiation led to significant increase in MDA, TC, TG and LDL, Meanwhile, significant decrease in GSH and SOD, but groups administrated with Artichoke [head and leaf] before whole body gamma irradiation, artichoke exerted noticeable amelioration against the radiation induced changes in most of the biochemical tested parameters

Increased Expression of EMMPRIN and VEGF in the Rat Brain after Gamma Irradiation

The extracellular matrix metalloproteinase inducer (EMMPRIN) has been known to play a key regulatory role in pathological angiogenesis. A elevated activation of vascular endothelial growth factor (VEGF) following radiation injury has been shown to mediate blood-brain barrier (BBB) breakdown. However, the roles of EMMPRIN and VEGF in radiation-induced brain injury after gamma knife surgery (GKS) are not clearly understood. In this study, we investigated EMMPRIN changes in a rat model of radiation injury following GKS and examined potential associations between EMMPRIN and VEGF expression. Adult male rats were subjected to cerebral radiation injury by GKS under anesthesia. We found that EMMPRIN and VEGF expression were markedly upregulated in the target area at 8-12 weeks after GKS compared with the control group by western blot, immunohistochemistry, and RT-PCR analysis. Immunofluorescent double staining demonstrated that EMMPRIN signals colocalized with caspase-3 and VEGF-positive cells. Our data also demonstrated that increased EMMPRIN expression was correlated with increased VEGF levels in a temporal manner. This is the first study to show that EMMPRIN and VEGF may play a role in radiation injuries of the central nervous system after GKS.

Protective role of wheat germ against hazards of radiotherapy with special references to its biochemical and pathological effect in male albino rats

Gamma [gamma] rays can penetrate the body of human being and due to damage multiple tissues and organ systems. Wheat germ is a Concentrated source of several essential nutrients. This study is to investigate the composition of photochemical compounds found in the wheat germ and its protective effect on the hazards due to radiation therapy. Forty eight of adult male albino rats were divided into four groups [12 rats of each]: the first group received the basal diet and served as negative control group. Rat groups from 2-4 were exposed to y-radiation doses of 0.5 Gy weekly for three weeks and in the same time groups 3 and 4 received wheat germ at two levels [100g and 200g/kg diet]. The result showed that there is improvement in most blood parameters in rats received wheat germ in their diets Hb, RBSc, and platelet value was significantly improved and increased. The malondialdehyde concentration was significantly decreased in alt organs tissue and serum. It can be concluded that the germ have plenty beneficial health effects especially against exposure hazards in human and animal subjects

Radiosensitivity and repair kinetics of gamma-irradiated leukocytes from sporadic prostate cancer patients and healthy individuals assessed by alkaline comet assay

Impaired DNA repair mechanism is one of the main causes of tumor genesis. Study of intrinsic radiosensitivity of cancer patients in a non-target tissue [e.g. peripheral blood] might show the extent of DNA repair deficiency of cells in affected individuals and might be used a predictor of cancer predisposition. Initial radiation-induced DNA damage [ratio of Tail DN A/Head DNA], dose-response curves and kinetics of DNA repair in leukocytes from healthy volunteers and prostate cancer patients were assessed using alkaline comet assay after exposure to [60]Co gamma rays. Results showed that higher levels of baseline and gamma rays induced DNA damage in leukocytes of prostate cancer cases than in controls. A similar dose response was obtained for both groups. After a repair time of 24 h following in vitro irradiation, samples from the healthy individuals showed no residual DNA damage in their leukocytes, whereas prostate cancer patients revealed more than 20%. Although similar initial radiosensitivity was observed for both groups, the repair kinetics of radiation induced DNA damage of leukocytes from prostate cancer cases and healthy subjects were statistically different. These results support the hypothesis that men affected by prostate cancer may have a constitutional genomic instability

Nutritional and Biochemical Studies on Roasted and Irradiated Sesame Seeds [Sesamum Indicium L.]

The main objectives of the present work are to study the effect of treated sesame seeds [Sesamum Indicium L] with roasting at 180°C for 15 min. and exposure to gamma irradiation at dose level of 2.5, 5 and 10 KGy on the antinutritional factors as well as evaluation of some biochemical analysis. In the present study groups of 10 rats were assigned to receive one of six experimental diets [i.e. raw roasted and irradiated sesame seeds up to 10 KGy diet, along side casein diet]. The statistical analysis indicated that there were significant results [p<0.05] decreased in the trypsin inhibitors, tannins of roasting and irradiated sesame seeds. There were no significant differences in the phenol compounds of sesame seeds processed compared with raw samples. The obtained data showed that the level of total serum protein and albumin were significantly lowered in rats fed raw sesame seeds [5.24 and 4.15 g dl[-1]] as compared with those fed casein diet [6.03 g dl[-1]]. Moreover, the rises of total serum protein of irradiation processing of sesame seeds up to 10 KGy was successful due to reducing the antinutritional factors by increasing irradiation process. With respect to the total serum albumin in rats fed irradiated sesame seeds at 5 and 10 KGy was close to that rats fed casein diet, followed with significant [p<0.05] decrease in the group of rats received in their diets irradiated sesame seeds at 2.5 KGy roasting and raw samples when compared with those fed casein diet. The statistical analysis showed that there were no significant variation in the liver enzymes [ALT and AST] between rats fed dry heated sesame seeds and those fed raw samples. But the level of liver enzymes [ALT and AST] decreased when rats fed sesame seeds irradiated up to 10 KGy as compared with rats fed raw seeds. Results showed significant decrease in total cholesterol, Triacylglycerol and low density lipoprotein cholesterol [LDL-C] and the results reflected increase in the high density lipoprotein [HDL-C] for rats received dry heated and irradiated [up to 10 KGy] sesame seeds when compared with those fed raw samples

Amifostine ameliorates recognition memory defect in acute radiation syndrome caused by relatively low-dose of gamma radiation

This study examined whether amifostine (WR-2721) could attenuate memory impairment and suppress hippocampal neurogenesis in adult mice with the relatively low-dose exposure of acute radiation syndrome (ARS). These were assessed using object recognition memory test, the terminal deoxynucleotidyl transferase-mediated dUTP nick end-labeling assay, and immunohistochemical markers of neurogenesis [Ki-67 and doublecortin (DCX)]. Amifostine treatment (214 mg/kg, i.p.) prior to irradiation significantly attenuated the recognition memory defect in ARS, and markedly blocked the apoptotic death and decrease of Ki-67- and DCX-positive cells in ARS. Therefore, amifostine may attenuate recognition memory defect in a relatively low-dose exposure of ARS in adult mice, possibly by inhibiting a detrimental effect of irradiation on hippocampal neurogenesis.

Modulation of radiation-induced cytotoxicity in U 87 cells by RH-3 (a preparation of Hippophae rhamnoides).

Background & objectives: Hippophae rhamnoides L. has been widely exploited for medicinal purposes and an extract of its whole berries coded as RH-3 has been found to render radioprotection. Effect of pre-irradiation treatment of up to 10 μg/ml RH-3 was studied in U 87 cells using MTT assay. This study aims at unraveling the mechanism of action of RH-3 in amelioration of radiation-induced cytotoxicity in vitro. Methods: Most effective doses selected were studied further for the elucidation of radiomodifying properties of RH-3, especially with respect to early and late events of apoptosis. Results: RH-3 at concentrations of 7.5 and 10 μg/ml (-15 min) were found most effective in protecting against 2 Gy induced cytotoxicity in terms of MTT reducing ability in U 87 cells. RH-3 was observed to mitigate radiation-induced cellular and mitochondrial free radicals. Mitochondrial membrane potential depletion (studied up to 12 h) was prevented by RH-3 pre-irradiation administration. It could also restore the level of antiapoptotic protein Bcl-2 at 24 and 48 h comparable to the control value. RH-3 also prevented radiation-induced increase in mitochondrial mass at 48 and 72 h post-treatment and the values were comparable to that of control cells. Annexin-V-FITC assay at 12 and 24 h time intervals indicated significant protection against radiation-induced apoptosis by RH-3 pre-irradiation treatment. Interpretation & conclusion: Our findings showed that probably RH-3 acts as an antioxidant preventing cellular and mitochondrial free radical generation that could contribute to its ability to inhibit radiationinduced apoptosis and cytotoxicity.

Qualidade microbiologica da carne de frango irradiada em embalagem convencional e a vácuo / Microbiological evaluation of chicken breast meat irradiated in conventional and vacuum package

Foram avaliados os efeitos da radiação gama nas doses de 1,5 e 3,0kGy, em peitos de frango embalados em embalagem convencional e a vácuo. As amostras embaladas foram submetidas à irradiação e estocadas sob refrigeração (4ºC) por 30 dias. A radiação mostrou-se eficiente na redução de mesófilos aeróbios estritos e facultativos viáveis, coliformes totais e termotolerantes, com destaque para Salmonella spp. Os bolores e leveduras mostraram-se bastante resistentes à radiação. Os resultados sugerem que a dose de 3,0kGy pode ser utilizada no controle da microbiota do peito de frango armazenado sob refrigeração, sendo uma alternativa para o aumento da vida de prateleira por até 10 dias, ao garantir a segurança do consumidor pela eliminação de possíveis patógenos.

The effects of gamma radiation doses of 1.5 and 3.0kGy on chicken breasts packed under conventional or vacuum atmosphere were evaluated. The packed samples were subjected to irradiation and stored under refrigeration (4ºC) for 30 days. The radiation was efficient in reducing strict and facultative aerobic mesophiles, total and fecal coliforms, and mainly Salmonella spp. The molds and yeasts were very resistant to radiation. The results suggest that gamma radiation at 3.0kGy can be used to control the microbiota in chicken breast stored under refrigeration, as an alternative to extend the shelf-life for more than ten days and ensure the food safety by eliminating potential pathogens.

Radioprotective effects of kojic acid against mortality induced by gamma irradiation in mice

To evaluate the protective effects of kojic acid on mortality induced by gamma irradiation in mice. The efficacy was compared with amifostine as a reference radioprotector. This experimental study was conducted in the Faculty of Pharmacy, Mazandaran University of Medical Sciences, Sari and Babolsar Radiotherapy Hospital, Babolsar, Iran, between October 2006 and January 2008. Kojic acid was administrated subcutaneously as single doses of 142, 175, 232, and 350 mg/kg, one hour prior to a lethal dose of gamma irradiation [8 Gy]. Amifostine was injected subcutaneously at a dose of 200 mg/kg at a similar irradiation dose. The mortality was recorded 30 days after irradiation. The antioxidant activity of the kojic acid was assessed using the 1, 1-diphenyl-2-picrylhydrazyl free stable radical [DPPH] method. One hundred and twenty NMRI mice were divided into 6 groups with 20 mice in each group. At 30 days after treatment, the percentage of survival in each group was: control, 5%; 142 mg/kg, 5%; 175 mg/kg, 0%; 232 mg/kg, 30%; 350 mg/kg, 40%; and amifostine, 40% one hour treatment prior gamma irradiation. The survival rate was statistically increased in animals treated with kojic acid [350 mg/kg], one hour prior irradiation, as compared with the irradiated control group. Kojic acid exhibited concentration-dependent scavenging activity on DPPH possessing strong antioxidant activity. Kojic acid with antioxidant activity reduced the mortality induced by gamma irradiation

Effect of sodium selenite on bone repair in tibiae of irradiated rats

This study evaluated the radioprotective effect of sodium selenite on the bone repair process in tibiae of female rats. For such purpose, 100 female Wistar rats (Rattus norvegicus, albinus) were randomly assigned to 4 groups (n=25), according to the treatment received: administration of distilled water (control); administration of sodium selenite; gamma radiation; and administration of sodium selenite plus gamma radiation. A bone defect was prepared on both tibiae of all animals. Three days after surgery, the gamma radiation and selenium/gamma radiation groups received 8 Gy gamma rays on the lower limbs. Five animals per group were sacrificed 7, 14, 21, 28 days after surgery for evaluation of the repair process by bone volumetric density analysis. The 5 animals remaining in each group were sacrificed 45 days postoperatively for examination of the mature bone by scanning electron microscopy. Based on all analyzed parameters, the results of the present study suggest that sodium selenite exerted a radioprotective effect in the bone repair of tibia of irradiated rats.

Este estudo avaliou o efeito radioprotetor de selenito de sódio no processo de reparação óssea em tíbias de ratas. Para isto, 100 ratas Wistar (Rattus norvegicus, albinus) foram aleatoriamente divididas em 4 grupos (n=25), de acordo com o tratamento recebido: administração de água destilada (controle); administração de selenito de sódio; irradiação gama; e administração de selenito de sódio mais irradiação gama. Um defeito ósseo foi realizado em ambas as tíbias de todos os animais. Três dias após a cirurgia, apenas os animais dos grupos irradiado e selênio/irradiado receberam 8 Gy de radiação gama na região dos membros inferiores. Cinco animais por grupo foram sacrificados 7, 14, 21 e 28 dias após a cirurgia para avaliação do processo de reparo ósseo pela análise da densidade óssea volumétrica. Os cinco animais remanescentes em cada grupo foram sacrificados aos 45 dias do pós-operatório para avaliação da maturação óssea por meio da microscopia eletrônica de varredura. Baseado em todos os parâmetros analisados, os resultados do presente estudo sugerem que o selenito de sódio exerceu efeito radioprotetor no reparo ósseo de tíbias de ratas irradiados.

Effect of gamma-irradiation on surface and catalytic properties of nano crystalline Fe2O3/CuO system

Ferric/copper mixed oxides samples having the formula 0.25Fe2O3/CuO were prepared by thermal decomposition of their mixed hydroxides at 400 °C. The mixed hydroxides were prepared by cooprecipitation method using iron and copper nitrates solution using NaOH at pH = 8. The obtained solid was exposed to different doses of gamma-rays varying between 0.2 MGy and 1.6 MGy. The techniques employed were XRD, nitrogen adsorption measurements at -196 °C and ethanol and isopropanol conversion using micropulse technique at temperatures between 250-400 °C. The results obtained revealed that the investigated system consisted of nano crystalline CuO [major phase] and poorly crystalline Fe2O3 as a minor phase. The exposure to gamma-irradiation resulted in a measurable decrease a the crystallite size of CuO [major phase], a dose of 1.6 MGy brought about a significant drop in the crystallite size from 31.4 to 19.2 nm. This treatment led also to a progressive increase in the BET=surface area to an extent proportional to the dose of gamma-rays employed. The investigated solid samples acted as dehydration catalysts converting ethanol and isopropanol into ethene and propene, respectively. Their activity was found to increase by increasing the dose of gamma-rays reaching to a maximum limit at a dose of 0.4 MGy. However, a dose of 0.8 MGy led to a sudden drop in the catalytic activity of various solids which retained most of their initial activity upon exposure to a dose of 1.6 MGy. The results obtained were discussed in terms of the role of gamma-rays in modifying the chemistry of the surface of the treated solids and the decrease in the crystallite size with subsequence increase in their SBET

Radioprotective effects of fucoidan on bone marrow cells: improvement of the cell survival and immunoreactivity

Fucoidan is a sulfated polysaccharide purified from brown algae including Fucus vesiculosus and has a variety of biological effects including mobilization of hematopoietic progenitor cells. Recently, we demonstrated that fucoidan stimulates the antigen-presenting functions of dendritic cells. In this study, we investigated the radioprotective effects of fucoidan on bone marrow cells (BMCs), which are the main cellular reservoir for the hematopoietic and immune system. To evaluate the effects of fucoidan, we assayed cell viability and immune responses. In a viability assay, fucoidan significantly increased the viability of BMCs. Based on the results of flow cytometric analysis, the increased viability of fucoidan-treated BMCs was attributed to the inhibition of radiation-induced apoptosis. Furthermore, fucoidan altered the production of immune-related cytokines from BMCs and increased the capability of BMCs to induce proliferation of allogeneic splenocytes. Taken together, our study demonstrated that fucoidan has radioprotective effects on BMCs with respect to cell viability and immunoreactivity. These results may provide valuable information, useful in the field of radiotherapy.

Effect of gamma rays on the bone repair process in rats with estrogen deficiency

This study aimed at evaluating the bone repair process in ovariectomized rats submitted to an irradiation procedure. For this purpose, one hundred rats were randomly divided in four experimental groups: control, ovariectomized, irradiated and irradiated/ovariectomized. A bone defect was made on all animals' tibias. Three days after surgery, only irradiated and irradiated/ovariectomized rats received 8 Gy of gamma rays on the lower limbs region. The animals were sacrificed 7, 14, 21 and 28 days after surgery in order to assess the repair process. It was possible to observe a delay in the bone repair process in the irradiated/ovariectomized group, in which there was a remarkable association between estrogen deficiency and ionizing radiation resulting in the reduction of newly formed bone production, thus accelerating the resorption process.

O objetivo deste trabalho foi avaliar o processo de reparo ósseo em ratas ovariectomizadas submetidas ao procedimento de irradiação. Para isto, cem ratas foram aleatoriamente divididas em quatro grupos experimentais: controle, ovariectomizado, irradiado e ovariectomizado/irradiado. Um defeito ósseo foi confeccionado nas tíbias de todos os animais. Três dias após a cirurgia, apenas os animais pertencentes aos grupos irradiado e ovariectomizado/irradiado receberam 8 Gy de radiação gama na região dos membros inferiores. Os animais foram sacrificados 7, 14, 21 e 28 dias após a cirurgia. Foi possível observar um atraso no processo de reparo ósseo nos animais do grupo ovariectomizado/irradiado, no qual houve uma marcante associação entre deficiência de estrógeno e radiação ionizante, resultando na redução da produção de osso neoformado, acelerando o processo de reabsorção.