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Increasing demand for safe, efficient, and eco-friendly solutions for pharmaceutical and food industries has led researchers to explore new approaches to bacterial storage. Several advantages make electrospinning (ES) a promising technique for food systems, including simple manufacturing equipment, a relatively low spinning cost, a wide variety of spinnable materials, and a mild process that is easily controlled, which allows continuous fabrication of ultrafine polymeric fibers at submicron or nanoscales without high temperatures or high pressures. This review briefly describes recent advances in the development of electrospun fibers for loading probiotics (PRB) by focusing on ES technology, its efficiency for loading PRB into fibers (viability, digestive stability, growth rate, release, thermal stability, and interactions of fibers with PRB), and the application of PRB-loaded fibers as active packaging (spoilage/microbial control, antioxidant effect, shelf life). Based on the literature reviewed, the incorporation of PRB into electrospun fibers is both feasible and functional. However, several studies have been limited to proof-of-principle experiments and the use of model biological products. It is necessary to conduct further research to establish the industrial applicability of PRB-loaded fibers, particularly in the fields of food and medicine.
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The presence of melamine in food is one of the most significant threats to consumer health and food safety now confronting the communities. The goal of this systematic review and meta-analysis was to determine the melamine content of different food products available on the Iranian market. The pooled melamine concentration (95% confidence interval) on 484 samples of animal-based foodstuffs was as follows: 0.22 (0.08, 0.36 mg kg-1) for milk, 0.39 (0.25, 0.53 mg kg-1) for coffee mate, 1.45 (1.36, 1.54 mg kg-1) for dairy cream, 0.90 (0.50, 1.29 mg kg-1) for yoghurt, 1.25 (1.20, 1.29 mg kg-1) for cheese, 0.81 (-0.16, 1.78 mg kg-1) for hen eggs, 1.28 (1.25, 1.31 mg kg-1) for poultry meat, 0.58 (0.35, 0.80 mg kg-1) for chocolates, and 0.98 (0.18, 1.78 mg kg-1) for infant formula. Based on the results of health risk assessment study on toddlers under 2 years old who ingested infant formula (as a melamine-sensitive group), all groups of toddlers are at an acceptable level of non-carcinogenic risk (THQ ≤ 1). Toddlers were classified according to their ILCR (carcinogenic risk) levels due to infant formula consumption as follows: under 6 months (0.0000056), 6-12 months (0.0000077), 12-18 months (0.0000102), and 18-24 months (0.0000117). The melamine carcinogenicity in infant formula for children had an ILCR value of 0.000001-0.0001 in the investigation, which was considerable risk. According to the findings, Iranian food products (notably infant formula) should be analyzed for melamine contamination on a regular basis.
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Contaminação de Alimentos , Fórmulas Infantis , Animais , Feminino , Irã (Geográfico) , Fórmulas Infantis/análise , Contaminação de Alimentos/análise , Galinhas , Medição de Risco , Triazinas/análiseRESUMO
Background and purpose: Alpha-lipoic acid (ALA) is an antioxidant with radioprotective properties. We designed the current work to assess the neuroprotective function of ALA in the presence of oxidative stress induced by radiation in the brainstem of rats. Experimental approach: Whole-brain radiations (X-rays) was given at a single dose of 25 Gy with or without pretreatment with ALA (200 mg/kg BW). Eighty rats were categorized into four groups: vehicle control (VC), ALA, radiation-only (RAD), and radiation + ALA (RAL). The rats were given ALA intraperitoneally 1 h before radiation and killed following 6 h, thereafter superoxide dismutase (SOD), catalase (CAT), malondialdehyde (MDA), and total antioxidant capacity (TAC) in the brainstem were measured. Furthermore, a pathological examination was carried out after 24 h, 72 h, and five days to determine tissue damage. Findings/Results: The findings indicated that MDA levels in the brainstem were 46.29 ± 1.64 µM in the RAD group and decreased in the VC group (31.66 ± 1.72 µM). ALA pretreatment reduced MDA levels while simultaneously increasing SOD and CAT activity and TAC levels (60.26 ± 5.47 U/mL, 71.73 ± 2.88 U/mL, and 227.31 ± 9.40 mol/L, respectively). The greatest pathological changes in the rat's brainstems were seen in RAD animals compared to the VC group after 24 h, 72 h, and 5 days. As a result, karyorrhexis, pyknosis, vacuolization, and Rosenthal fibers vanished in the RAL group in three periods. Conclusion and implications: ALA exhibited substantial neuroprotectivity following radiation-induced brainstem damage.
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AIM: This study aimed to assess the effects of iron salts on the demineralization and discoloration of primary incisor enamel subjected to artificial cariogenic challenge (ACC) versus saline immersion. METHODOLOGY: In this in vitro experimental study, 90 primary incisors were evaluated in 10 groups (n = 9). Five groups were subjected to ACC, and the other five were immersed in saline. Ferrous sulfate, ferrous fumarate, ferrous ammonium citrate, and ferrous gluconate were added to both saline and cariogenic solutions. The solutions were refreshed every 48 h. After 14 days, the teeth were removed from the media and their demineralization was inspected via scanning electron microscopy (SEM). Energy-dispersive X-ray spectroscopy (EDX) was also performed. The color of the specimens was measured at baseline and after the intervention using the Vita Shade Guide. RESULTS: Data were analyzed by the Kruskal-Wallis test, one-way ANOVA, and Tukey's test. The color change of specimens subjected to ACC was greater than the color change of those in saline (p = 0.083). The teeth subjected to ACC showed greater iron uptake than did those in saline (p = 0.023). SEM assessment revealed a regular pattern of enamel prisms, with some broken prisms and superficial cracks in the teeth immersed in saline. The teeth subjected to ACC showed numerous fractures and cracks, which were greater in the ferrous sulfate group. CONCLUSIONS: Immersion in ACC increased the structural porosities and led to greater iron uptake and, consequently, higher discoloration. The maximum structural changes and subsequent staining were noted in the ferrous sulfate group, followed by ferrous ammonium citrate, ferrous fumarate, and ferrous gluconate.
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PURPOSE: This study aimed to determine the radioprotective effect of N-acetylcysteine (NAC) on the radiation-induced oxidative stress (OS) in the rats' brainstem. MATERIALS AND METHODS: Eighty rats in four identical groups, including vehicle control (VC), irradiation alone (RAD), irradiation with 1 g/kg of NAC treatment (RAN), and NAC treatment without radiation (NAC) were used. Whole-brain irradiation was performed with a single dose of 25 Gy. The rats received the treatments via intraperitoneal (IP) injection 1 h before the irradiation process. Nitric oxide (NO), malondialdehyde (MDA), superoxide dismutase (SOD), catalase (CAT), total antioxidant capacity (TAC), and glutathione peroxidase (GPx) were measured in the rats' brainstem and compared between the groups. Furthermore, the pathological study was performed to assess tissue damage after 24 h, 72 h, and 5 days of irradiation. RESULTS: The levels of NO and MDA in the brainstem tissue for the RAD group were 60.37 ± 3.35 µmol/L and 45.10 ± 2.48 µM, respectively, which were higher than those of VC group (NO: 30.41 ± 1.83 µmol/L; MDA: 31.02 ± 1.71 µM). The level of SOD, CAT, TAC, and GPx declined in the RAD compared to the VC group. Pre-treatment with NAC decreased the level of NO and MDA and also enhanced the antioxidant activities. The greatest pathological changes in the rats' brainstems were seen in RAD animals compared to the VC group at 24 h, 72 h, and 5 days. Furthermore, the pathological changes were not observed in the NAC group in all the assessed times. CONCLUSION: Based on the results, NAC can decrease the irradiation-induced oxidative stress and pathology damages in the rats' brainstem. It can be concluded that NAC can be an appropriate radioprotection candidate for the human brainstem.
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Acetilcisteína , Antioxidantes , Tronco Encefálico , Protetores contra Radiação , Acetilcisteína/farmacologia , Animais , Antioxidantes/metabolismo , Tronco Encefálico/metabolismo , Tronco Encefálico/efeitos da radiação , Glutationa Peroxidase/metabolismo , Malondialdeído/metabolismo , Protetores contra Radiação/farmacologia , Ratos , Superóxido Dismutase/metabolismo , Raios X/efeitos adversosRESUMO
COVID-19 has recently grown to be pandemic all around the world. Therefore, efforts to find effective drugs for the treatment of COVID-19 are needed to improve humans' life quality and survival. Since the main protease (Mpro) of SARS-CoV-2 plays a crucial role in viral replication and transcription, the inhibition of this enzyme could be a promising and challenging therapeutic target to fight COVID-19. The present study aims to identify alkaloid compounds as new potential inhibitors for SARS-CoV-2 Mpro by the hybrid modeling analyses. The docking-based virtual screening method assessed a collection of alkaloids extracted from over 500 medicinal plants and sponges. In order to validate the docking process, classical molecular dynamic simulations were applied on selected ligands, and the calculation of binding free energy was performed. Based on the proper interactions with the active site of the SARS-CoV-2 Mpro, low binding energy, few side effects, and the availability in the medicinal market, two indole alkaloids were found to be potential lead compounds that may serve as therapeutic options to treat COVID-19. This study paves the way for developing natural alkaloids as stronger potent antiviral agents against the SARS-CoV-2.
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Alcaloides , Tratamento Farmacológico da COVID-19 , Alcaloides/farmacologia , Antivirais/química , Antivirais/farmacologia , Humanos , Alcaloides Indólicos , Simulação de Acoplamento Molecular , Simulação de Dinâmica Molecular , Inibidores de Proteases/química , Inibidores de Proteases/farmacologia , Inibidores de Proteases/uso terapêutico , SARS-CoV-2RESUMO
Background: The dose values obtained from procedures of diagnostic radiology are relatively low. To accurately and precisely measure the dose values in this dose range, it is necessary to know the characteristics of dosimeters. Objective: The aim of this study was to evaluate several thermoluminescent characteristics of GR-200, TLD-700H and TLD-100 for low dose measurement. Material and Methods: In this experimental study, linearity, repeatability, dose rate and photon energy dependence of different TLD materials were investigated in a 0.05-10 mGy range dose. It is noteworthy that the data obtained from TLD-100 were considered as reference and the data obtained from two other types of TLDs were compared with them. Results: For all three types of TLD materials, there are linear relations between absorbed dose values to TLDs and their responses. TLD-100 and TLD-700H have very low sensitivity than GR-200. For GR-200 and TLD-100, the coefficients of variation values (%) are 3.00% and 2.01%, respectively, that these values are within the tolerance limit (<7.5%). However, this value for TLD-700H is 10.85% which it is more than the reported tolerance limit. Furthermore, remarkable effects of dose rate and photon energy dependence on the responses of GR-200 are not observed in a 0.5-4 mGy dose range; nevertheless, remarkable effects of dose rate and photon energy dependence on the responses of TLD-100 and TLD-700H are found in this dose range. Conclusion: The evaluated thermoluminescent characteristics for GR-200 are better than two other types of TLDs (TLD-100 and TLD-700H) for low dose values.
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Background and Objectives: Due to the nutritional and behavioral patterns of children, their teeth can be a good indicator of heavy metal uptake from over the years. To determine the amount of Zn, Cu, Cd, and Pb accumulated in the body, primary teeth of children in Zanjan, Iran, were examined with a polarography device. Materials and Methods: Samples were collected from dentistry clinics of Zanjan, Iran, and were prepared for acid digestion, and then were analyzed by a polarography device for determining the concentration of lead, copper, zinc, and cadmium. Results: Data were analyzed by a t-independent test to compare different groups (p < 0.05). Based on the results obtained from this study, the mean concentrations of zinc, lead, copper, and cadmium were 245, 7.66, 5.33, and 0.0879 µg/g, respectively, which shows that the amount of each of the four elements was more than the amounts that have been reported for different countries. The results showed no significant difference between age, tooth type, and jaw groups. Conclusions: We conclude that primary teeth are an important biological indicator to evaluate the concentration of heavy elements in the human body. The high concentrations of these elements in the primary teeth analyzed in this study could be attributed to the high concentrations of these elements in the environment of Zanjan.
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Metais Pesados , Polarografia , Cádmio , Criança , Odontologia , Humanos , ZincoRESUMO
BACKGROUND: Lead (Pb2+ ) is one of the most toxic heavy metals and can be found in various quantities in the environment. The five native probiotic bacteria and inulin were used to assess in vitro lead nitrate and lead acetate binding capacities, as well as removal potentials. RESULTS: The highest decrease in media pH was seen for samples containing a combination of Lactobacillus paracasei IRBC-M 10784, lead nitrate and inulin (5.30 ± 0.012). The presence of inulin in the environment accelerated decreases in the pH of all samples with no significance. In all groups, lead nitrate-containing samples included maximum pH decreases. From the highest to the lowest, the ability of lead removal was linked to Lactobacillus acidophilus PTCC-1932 (88.48%), Bifidobacterium bifidum BIA-7 (85.32%), Bifidobacterium lactis BIA-6 (85.24%), Lactobacillus rhamnosus IBRC-M 10782 (83.18%) and L. paracasei IRBC-M 10784 (80.66%). Most species included the highest decrease in lead nitrate. Fourier-transform infrared spectroscopy (FTIR) analysis demonstrated that various functional groups (hydroxyl, carboxylic, carbonyl, amino and amide binds) on the bacterial cell wall were involved in lead ion binding during incubation. Principal component analysis of the FTIR results showed differences with respect to treated groups and control groups. CONCLUSION: The results obtained in the present study reveal that the simultaneous use of native probiotics and inulin can be an effective and safe approach for removing various toxic substances, especially Pb. © 2021 Society of Chemical Industry.
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Bifidobacterium/metabolismo , Inulina/química , Lactobacillus/metabolismo , Chumbo/metabolismo , Nitratos/metabolismo , Compostos Organometálicos/metabolismo , Adsorção , Bifidobacterium/química , Biodegradação Ambiental , Parede Celular/química , Parede Celular/metabolismo , Concentração de Íons de Hidrogênio , Lactobacillus/química , Chumbo/química , Nitratos/química , Compostos Organometálicos/química , Probióticos/química , Probióticos/metabolismoRESUMO
OBJECTIVE: Although radiation exposure associated with dental radiography is relatively low, patient exposure must be kept practically low. Therefore, it is necessary for each country to establish its own diagnostic reference levels (DRLs) suitable for its equipment and practice. In the present study, dose-width product (DWP) values for panoramic dental radiography were measured and a local DRL was established. METHODS: Five panoramic devices from five radiology clinics of Kashan, Iran were selected to measure the DWP values of panoramic dental radiography. To investigate the DWP values, the parameters of each patient's exposure (e.g., tube voltage, tube current, and exposure time) at these five radiology clinics were extracted. Then, the dose value received by each patient was measured based on a CT pencil chamber. Finally, the overall median DWP values for the patients with small, medium, and large sizes were obtained, and these values were considered as the local DRLs for panoramic dental radiography. RESULTS: A total of 99 adult patients were included in the present study. The findings demonstrated that the median and third-quartile DWP values for these five radiology clinics ranged from 42.3 to 94.3 and 49.7 to 142.8 mGy mm, respectively. The local DRL values, which were established as the overall median DWP values, were 43.4, 52.0, and 80.3 mGy mm for the adults with small, medium, and large sizes, respectively. CONCLUSION: The local DRL proposed in this study for the adult with standard/medium size was lower than those proposed by other reports and seemed acceptable for panoramic radiography in Kashan, Iran.
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Níveis de Referência de Diagnóstico , Radiometria , Adulto , Humanos , Irã (Geográfico) , Doses de Radiação , Radiografia PanorâmicaRESUMO
PURPOSE: This study aimed to design optimal flattening filters for high dose rate (HDR) 192Ir and 60Co Leipzig applicators which are used to treat skin cancer. MATERIALS AND METHODS: MCNPX Monte Carlo code was used to design flattening filters for Leipzig applicators with inner diameters of 1, 2 and 3 cm. Then, their dosimetric characterizations such as dose distribution, dose profile, percentage depth dose, flatness, symmetry and homogeneity were evaluated in a 20 × 20 × 20 cm3 water phantom and compared with those without the flattening filter. RESULTS: The flattening filter thickness varied from 0 mm (at the edge) to the maximum values of 0.30, 1.18, and 2.41 mm for the 192Ir Leipzig applicators of H1, H2, and H3 type, respectively. This quantity has maximum values of 0.96, 6.27, and 12.31 mm for the 60Co double wall applicators of D1, D2, and D3 type, respectively. The dose profile flatness values for the H1, H2, and H3 192Ir Leipzig applicators with the optimal flattening filters were 0.76, 1.26, and 1.85%, respectively. Furthermore, the dose profile flatness values for the D1, D2, and D3 60Co double wall applicators with the optimal flattening filters were 1.11, 2.10 and 3.12%, respectively. The dose profile symmetry values obtained from various source-applicator combinations were less than 1.02. Compared to the applicators without flattening filter, the homogeneity values for the H1, H2, and H3 192Ir Leipzig applicators with the optimal flattening filters were improved 1.68, 6.51, and 13.17 times, respectively, and for the D1, D2, and D3 60Co double wall applicators were improved 1.23, 6.21 and 9.54 times, respectively. CONCLUSION: The findings revealed that the inhomogeneous dose distribution resulted from the Leipzig applicators without the optimal flattening filter at the treatment surface could be improved by insertion of optimal lead flattening filters between the sources and treatment surface.
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Braquiterapia , Neoplasias Cutâneas , Humanos , Radioisótopos de Irídio/uso terapêutico , Método de Monte Carlo , Radiometria , Dosagem RadioterapêuticaRESUMO
The present study evaluated the protective effect of Lactobacillus acidophilus against the toxicity of the Beauvericin on the Caco-2 cell line. After culturing Caco-2 cells and applying different concentrations of Beauvericin and L. acidophilus individually and in combination, cell viability was assessed by enzyme-linked immunosorbent assay at different times. The results indicate the potential risk of Beauvericin to human health and the interventional role of L. acidophilus, which improved cell viability in the presence of Beauvericin.
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Depsipeptídeos/toxicidade , Lactobacillus acidophilus , Micotoxinas/toxicidade , Células CACO-2 , Humanos , Lactobacillus , ProbióticosRESUMO
The aim of radiotherapy is to deliver the highest possible radiation dose to the tumor and the lowest radiation to normal tissues surrounding the tumor. In the present study, lymph nodes of the supraclavicular region were treated using two therapeutic techniques, namely photon technique (PT) and combinatory photon-electron technique (CPET). We recruited 50 patients with local lymph node metastasis. The photon energies were 6-15 MV. Furthermore, the electron beam energy was 18 MeV in CPET. The study findings revealed that the mean delivered dose to target volume was 41.12 ± 2.98Gy for PT and 44.56 ± 1.90Gy for CPET. The percentage of the target volume irradiated to 90% of the prescribed dose (V90) was calculated as 74.61% ± 9.30% and 82.06% ± 9.70% for PT and CPET, respectively. The mean dose delivered to the heart and lungs was not significantly different between the two groups. Furthermore, the maximum doses delivered to the spinal cord were 12.55Gy in PT and 8.89Gy in CPET. The mean doses delivered to the thyroid gland were 39.26 and 34.89Gy in PT and CPET. According to the study results, the maximum doses delivered to the spinal cord, head of the humerus bone, and thyroid were reduced significantly as measured the CPET technique. In contrast, no significant difference was observed regarding the dose delivered to the heart and lung. The dose delivered to the supraclavicular region determined by the CPET was significantly augmented. Furthermore, the coverage of the tumor mass was optimized using the new method.
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This study aimed to determine the effects of melatonin on irradiation-induced apoptosis and oxidative stress in the brainstem region of Wistar rats. Therefore, the animals underwent whole-brain X-radiation with a single dose of 25 Gy in the presence or absence of melatonin pretreatment at a concentration of 100 mg/kg BW. The rats were allocated into four groups (10 rats in each group): namely, vehicle control (VC), 100 mg/kg of melatonin alone (MLT), irradiation-only (RAD), and irradiation plus 100 mg/kg of melatonin (RAM). An hour before irradiation, the animals received intraperitoneal (IP) melatonin and then were killed after 6 hr, followed by measurement of nitric oxide (NO), malondialdehyde (MDA), superoxide dismutase (SOD), glutathione peroxidase (GPx), catalase (CAT), and total antioxidant capacity (TAC) in the brainstem region. Furthermore, the western blot analysis technique was performed to assess the caspase-3 expression level. Results showed significantly higher MDA and NO levels in the brainstem tissues for the RAD group when compared with the VC group (p < .001). Moreover, the irradiated rats exhibited a significant decrease in the levels of CAT, SOD, GPx, and TAC (p < .01, p < .001, p < .001, and p < .001, respectively) in comparison to the VC group. The results of apoptosis assessment revealed that the expression level of caspase-3 significantly rose in the RAD group in comparison with the VC group (p < .001). Pretreatment with melatonin ameliorated the radiation-induced adverse effects by decreasing the MDA and NO levels (p < .001) and increasing the antioxidant enzyme activities (p < .001). Consequently, the caspase-3 protein expression level in the RAM group showed a significant reduction in comparison with the RAD group (p < .001). In conclusion, melatonin approximately showed a capacity for neuroprotective activity in managing irradiation-induced oxidative stress and apoptosis in the brainstem of rats; however, the use of melatonin as a neuroprotective agent in humans requires further study, particularly clinical trials.
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Apoptose/efeitos dos fármacos , Tronco Encefálico/efeitos dos fármacos , Glutationa Peroxidase/efeitos dos fármacos , Melatonina/uso terapêutico , Estresse Oxidativo/efeitos dos fármacos , Animais , Antioxidantes/farmacologia , Tronco Encefálico/metabolismo , Glutationa Peroxidase/metabolismo , Masculino , Malondialdeído/metabolismo , Fármacos Neuroprotetores/farmacologia , Ratos Wistar , Superóxido Dismutase/metabolismoRESUMO
AIM: In this study, we aimed to determine possible mitigation of radiationinduced toxicities in the duodenum, jejunum and colon using post-exposure treatment with resveratrol and alpha-lipoic acid. BACKGROUND: After the bone marrow, gastrointestinal system toxicity is the second critical cause of death following whole-body exposure to radiation. Its side effects reduce the quality of life of patients who have undergone radiotherapy. Resveratrol has an antioxidant effect and stimulates DNA damage responses (DDRs). Alpha-lipoic acid neutralizes free radicals via the recycling of ascorbic acid and alpha-tocopherol. OBJECTIVE: This study is a pilot investigation of the mitigation of enteritis using resveratrol and alpha-lipoic acid following histopathological study. METHODS: 60 male mice were randomly assigned to six groups; control, resveratrol treatment, alpha-lipoic acid treatment, whole-body irradiation, irradiation plus resveratrol, and irradiation plus alpha-lipoic acid. The mice were irradiated with a single dose of 7 Gy from a cobalt-60 gamma-ray source. Treatment with resveratrol or alpha-lipoic acid started 24 h after irradiation and continued for 4 weeks. All mice were sacrificed after 30 days for histopathological evaluation of radiation-induced toxicities in the duodenum, jejunum and colon. RESULTS AND DISCUSSION: Exposure to radiation caused mild to severe damages to vessels, goblet cells and villous. It also led to significant infiltration of macrophages and leukocytes, especially in the colon. Both resveratrol and alpha-lipoic acid were able to mitigate morphological changes. However, they could not mitigate vascular injury. CONCLUSION: Resveratrol and alpha-lipoic acid could mitigate radiation-induced injuries in the small and large intestine. A comparison between these agents showed that resveratrol may be a more effective mitigator compared to alpha-lipoic acid.
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Lesões Experimentais por Radiação/tratamento farmacológico , Protetores contra Radiação/uso terapêutico , Resveratrol/uso terapêutico , Ácido Tióctico/uso terapêutico , Animais , Colo/efeitos dos fármacos , Colo/patologia , Colo/efeitos da radiação , Duodeno/efeitos dos fármacos , Duodeno/patologia , Duodeno/efeitos da radiação , Raios gama/efeitos adversos , Jejuno/efeitos dos fármacos , Jejuno/patologia , Jejuno/efeitos da radiação , Masculino , Camundongos , Lesões Experimentais por Radiação/patologia , Irradiação Corporal Total/efeitos adversosRESUMO
BACKGROUND: Various factors effecting deposited energy and dose enhancement ratio (DER) in the simplified model of cell caused by the interaction of a cluster of gold nanoparticles (GNPs) with electron beams were assessed, and the results were compared with other sources through Geant4 Monte Carlo simulation toolkit. METHOD: The effect of added GNPs on the DNA strand breaks level, irradiated to electron, proton, and alpha beams, is assessed. RESULTS: Presence of GNPs in the cell makes DER value more pronounced for low-energy photons rather than electron beam. Moreover, the results of DER values did not show any significant increase in absorbed dose in the presence of GNP for proton and alpha beam. Moreover, the results of DNA break with GNPs for proton and alpha beam were negligible. It is demonstrated that as the sizes of the GNPs increase, the DER is enlarged until a certain size for 40 keV photons, while there is no striking change for 50 keV electron beam when the size of the GNPs changes. The results indicate that although energy deposited in the cell for electron beam is more than low-energy photon, DER values are low compared to photon. CONCLUSION: Larger GNPs do not show any preference over smaller ones when irradiated through electron beams. It is proved that GNPs do not significantly increase single-strand breaks (SSBs) and double-strand breaks during electron irradiation, while there exists a direct relationship between SSB and energy.
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OBJECTIVE: The Lung is one of the most radiosensitive organs of the body. The infiltration of macrophages and lymphocytes into the lung is mediated via the stimulation of T-helper 2 cytokines such as IL-4 and IL-13, which play a key role in the development of fibrosis. It is likely that these cytokines induce chronic oxidative damage and inflammation through the upregulation of Duox1 and Duox2, which can increase the risk of late effects of ionizing radiation (IR) such as fibrosis and carcinogenesis. In the present study, we aimed to evaluate the possible increase of IL-4 and IL-13 levels, as well as their downstream genes such as IL4ra1, IL13ra2, Duox1, and Duox2. MATERIALS AND METHODS: In this experimental animal study, male rats were divided into 4 groups: i. Control, ii. Melatonintreated, iii. Radiation, and iv. Melatonin (100 mg/kg) plus radiation. Rats were irradiated with 15 Gy 60Co gamma rays and then sacrificed after 67 days. The expressions of IL4ra1, IL13ra2, Duox1, and Duox2, as well as the levels of IL-4 and IL-13, were evaluated. The histopathological changes such as the infiltration of inflammatory cells, edema, and fibrosis were also examined. Moreover, the protective effect of melatonin on these parameters was also determined. RESULTS: Results showed a 1.5-fold increase in the level of IL-4, a 5-fold increase in the expression of IL4ra1, and a 3-fold increase in the expressions of Duox1 and Duox2. However, results showed no change for IL-13 and no detectable expression of IL13ra2. This was associated with increased infiltration of macrophages, lymphocytes, and mast cells. Melatonin treatment before irradiation completely reversed these changes. CONCLUSION: This study has shown the upregulation of IL-4-IL4ra1-Duox2 signaling pathway following lung irradiation. It is possible that melatonin protects against IR-induced lung injury via the downregulation of this pathway and attenuation of inflammatory cells infiltration.
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Background: Radiation-induced heart injury can lead to increased risk of heart failure, attack, and ischemia. Some studies proposed IL-4 and IL-13 as two important cytokines that are involved in late effects of ionizing radiation. On the other hand, these cytokines may, through upregulation of Duox1 and Duox2, induce chronic oxidative stress, inflammation, and fibrosis. In this study, we evaluated the upregulation of Duox1 and Duox2 pathways in hearts following chest irradiation in rats and then detected possible attenuation of them by melatonin. Materials and Methods: Twenty male Wistar rats were divided into four groups: (1) control; (2) melatonin treated (100 mg/kg); (3) radiation (15 Gy gamma rays); (4) melatonin treated before irradiation. All rats were sacrificed after 10 weeks and their heart tissues collected for real-time PCR (RT-PCR), ELISA detection of IL-4 and IL-13, as well as histopathological evaluation of macrophages and lymphocytes infiltration. Results: Results showed an upregulation of IL-4, IL4ra1, Duox1, and Duox2. The biggest changes were for IL4ra1 and Duox1. Treatment with melatonin before irradiation could attenuate the upregulation of all genes. Melatonin also caused a reduction in IL-4 as well as reverse infiltration of inflammatory cells. Conclusion: Duox1 and Duox2 may be involved in the late effects of radiation-induced heart injury. Also, via attenuation of these genes, melatonin can offer protection against the toxic effects of radiation on the heart.
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Oxidases Duais/efeitos da radiação , Melatonina/farmacologia , Regulação para Cima/efeitos da radiação , Análise de Variância , Animais , Antioxidantes/farmacologia , Antioxidantes/uso terapêutico , Modelos Animais de Doenças , Ensaio de Imunoadsorção Enzimática/métodos , Cardiopatias Congênitas , Masculino , Melatonina/uso terapêutico , Fatores de Proteção , Lesões por Radiação , Ratos , Ratos Wistar , Regulação para Cima/fisiologiaRESUMO
This study aimed to evaluate the composition, antioxidant capacity and antibacterial effects of Pistacia atlantica subsp. kurdica (baneh) essential oil on some important bacteria in food safety. Essential oil was derived using hydro-distillation method of the baneh fruits. Essential oil composition was determined using gas chromatography-mass spectrometry. The 2,2'-azinobis-(3-ethylbenzothiaziline-6-sulfonate; ABTS) and 2,2-diphenyl-1-picrylhydrazyl (DPPH) methods were used to evaluate antioxidant activity and Folin-Ciocalteu method was used to determine total phenolic content of essential oil. The antibacterial effect of the essential oil against six pathogen bacteria was determined using minimum inhibitory concentration, minimum bactericidal concentration and disc diffusion methods. Monoterpene and sesquiterpene hydrocarbons were main compounds of total identified constituents in the essential oil (approximately 93.50% and 5.45%, respectively). The main compounds were α-pinene, myrcene, limonene, ß-pinene and γ-terpineol, respectively. The mean concentration of essential oil providing 50.00% inhibition was 7.54 ± 0.01 mg mL-1. Dose-dependent and scavenging activities were seen in DPPH and ABTS tests and total phenolic content within test range of concentrations (0.0625 to 4.00 mg mL-1). The highest DPPH radical scavenging activity (48.67 ± 0.84%) was seen at a concentration of 4 mg mL-1. The responses of essential oil concentrations to ABTS assay were quite similar to the DPPH reaction, especially in higher concentrations. Both antimicrobial methods demonstrated that the essential oil had broader antibacterial effects against the Gram-positive bacteria than the tested Gram-negative bacteria. Essential oil of Pistachia atlantica subsp. kurdica can be one of the performing essential oils to be used as a preservative in food industry to increase food safety and reduce food pathogens risks.
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BACKGROUND: Nowadays, the use of computed tomography (CT) as a diagnostic tool has been considerably increased. Therefore, implementation of the program to conform the protection regulations on the CT scan is necessary to reduce the detrimental effects of radiation. OBJECTIVE: This study was performed to measure weighted CT dose index (CTDIW) and dose length product (DLP) in routine CT protocols of the adult patients. METHODS: In this study, the patient dose was determined in routine CT protocols. The CT scanner used in this study was a single-slice Toshiba model. Scan parameters for each protocol were registered for 10 standard sized patients and then by applying it to the CT system, CTDIw and DLP mean values were calculated and finally the values of dose were compared with the reference dose limit. RESULTS: The mean values of CTDIw and DLP for head, para nasal sinuses, chest, abdomen, and pelvis protocols were 34.11, 19.67, 15.47, 13.95, 10.08 mGy and 362.67, 153.97, 307.33, 346.07, 189.37 mGy.cm, respectively. The mean values of CTDIW and DLP obtained in all of the protocols were less and even less than half in some of the protocols compared with the European guidelines and the UK reference values. However, mean values of CTDIw in the Chest and Abdomen protocols, were greater than IAEA reported values. CONCLUSIONS: Using lower milli Amperes and higher kilo voltage peak as well as minimizing scan area and number of slices should be considered for more reduction in patients' dose.