Study of the radiomodifier effect of Pityrocarpa moniliformis extract

2019 ◽  
Vol 7 (2A) ◽  
Author(s):  
João Victor Torres de Moraes ◽  
Ricardo Luiz Calazans Luna Filho ◽  
Williams Nascimento de Siqueira ◽  
Hianna Arely Milca Fagundes Silva ◽  
Dewson Rocha Pereira ◽  
...  
Keyword(s):  
Ionizing Radiation ◽  
Cellular Response ◽  
Biomphalaria Glabrata ◽  
Toxicity Tests ◽  
Antioxidant Compounds ◽  
Blastula Stage ◽  
Natural Substances ◽  
60Co Source ◽  
60Co Gamma ◽  
60Co Gamma Radiation

Ionizing radiation has been applied in several areas of knowledge, among them the study of the radiomodifier activity of natural substances. These substances can modify the cellular response to the damage induced by the radiation. Therefore, this work aimed to evaluate the radiomodifier action of Pityrocarpa moniliformis extract on Biomphalaria glabrata embryos exposed to 60Co gamma radiation. Initially, toxicity tests were performed on the extract against the B. glabrata embryos for the choice of concentration that did not cause death and embryonic malformation. Then, the antioxidant activity of the P. moniliformis extract with flavonoids and phenolic compounds was evaluated by means of the ABTS method. To evaluate the radiomodifier activity of the extract, embryos were selected in the blastula stage and irradiated with 7.5 Gy in a 60Co source (gammacell-Co60). Then, the embryos were exposed for 24 h to the extract of P. moniliformis at a concentration of 250 μg/mL. The results showed that the extract of P. moniliformis presents flavonoids and enzymatic inhibition by ABTS, which demonstrates the presence of antioxidant compounds. However, the tests of the radiomodifier activity did not present radioprotective effect for embryos exposed to ionizing radiation.

Dominant lethal effect of 60Co gamma radiation in Biomphalaria glabrata (SAY, 1818)

2004 ◽  
Vol 561 (1-2) ◽  
pp. 139-145 ◽  
Author(s):  
Lenita de Freitas Tallarico ◽  
Kayo Okazaki ◽  
Toshie Kawano ◽  
Carlos Alberto de Bragança Pereira ◽  
Eliana Nakano
Keyword(s):  
Gamma Radiation ◽  
Lethal Effect ◽  
Biomphalaria Glabrata ◽  
Dominant Lethal ◽  
60Co Gamma ◽  
60Co Gamma Radiation

scholarly journals Use of Chemical Dosimetry for Comparison of Ultrasound and Ionizing Radiation Effects on Cavitation

2007 ◽  
pp. S77-S84
Author(s):  
B. Kratochvíl ◽  
V. Mornstein
Keyword(s):  
Ionizing Radiation ◽  
High Frequency ◽  
Radiation Effects ◽  
Potassium Iodide Solution ◽  
Chemical Changes ◽  
60Co Source ◽  
60Co Gamma ◽  
Iodide Solution ◽  
Chemical Dosimetry ◽  
Relationship Of

A comparison of the effects of ultrasound produced by low- and high-frequency ultrasonic apparatuses upon biological systems is one of the basic problems when studying ultrasound cavitation effects. One possibility for how to compare these effects is the indirect method which uses well-known physical quantities characterizing the interaction of ionizing radiation with matter and which also converts these quantities to one common physical quantity. The comparison was performed with two methods applied to the chemical dosimetry of ionizing radiation. The first method employed a twocomponent dosimeter which is composed of 50 % chloroform and 50 % re-distilled water (i.e. Taplin dosimeter). The other method used a modified iodide dosimeter prepared from a 0.5 M potassium iodide solution. After irradiation or ultrasound exposure, measurable chemical changes occurred in both dosimeters. The longer the exposure, the greater the chemical changes. These effects are described by the relationship of these changes versus the exposure times in both dosimeters. The UZD 21 ultrasonic disintegrator (with a frequency of 20 kHz, 50 % power output) was used as a lowfrequency ultrasound source, and the BTL-07 therapeutic instrument (with a frequency of 1 MHz and intensity of 2 W/cm2 ) was used as a high-frequency cavitation ultrasound source. For comparison, a 60Co gamma source was applied ( 60Co, gamma energies of 1.17 and 1.33 MeV, activity of 14 PBq). Results of this study have demonstrated that the sonochemical products are generated during exposure in the exposed samples of both dosimeters for all apparatuses used. The amount of these products depends linearly upon the exposure time. The resulting cavitation effects were recalculated to a gray-equivalent dose (the proposed unit is cavitation gray [cavitGy]) based on the sonochemical effects compared to the effects of ionizing radiation from the 60Co source.

scholarly journals Disruption of ATM in p53-null cells causes multiple functional abnormalities in cellular response to ionizing radiation

Oncogene ◽  
1999 ◽  
Vol 18 (50) ◽  
pp. 7002-7009 ◽  
Author(s):  
Noriaki Takao ◽  
Hideaki Kato ◽  
Ryoichi Mori ◽  
Ciaran Morrison ◽  
Eiichiro Sonada ◽  
...  
Keyword(s):  
Ionizing Radiation ◽  
Cellular Response

scholarly journals Изменение характеристик переизлучающих волокон Y-11 и O-2 под действием гамма облучения

2020 ◽  
Vol 128 (12) ◽  
pp. 1973
Author(s):  
А.Ю. Афанасьев ◽  
А.Ю. Бояринцев ◽  
И.А. Голутвин ◽  
Э.М. Ибрагимова ◽  
А.И. Малахов ◽  
...  
Keyword(s):  
Gamma Radiation ◽  
Dose Rate ◽  
Room Temperature ◽  
Low Dose ◽  
Low Dose Rate ◽  
60Co Gamma ◽  
60Co Gamma Radiation

The effect of 60Co gamma radiation on the intensity of the reemitted light at the exit from WLS-fibers of Y-11 M and O-2 M type WLS fibers and the subsequent restoration of the characteristics of irradiated fibers after exposure to room temperature are investigated. Irradiation of a low dose rate (0.048 Mrad / h) to a dose of 1 Mrad leads to a slight decrease in the intensity of the reemitted light at the exit of both types of fibers, and with a further increase in the dose, the curve does not change. When irradiated with a dose rate of 0.158 Mrad / h, the characteristics of both types of fibers deteriorate significantly. When the irradiated samples are held at room temperature, fiber characteristics are restored.

scholarly journals Disinfection of Archived Material by Radiation Processing Technology Keeping the Material Integrity

2018 ◽  
Vol 33 (1-2) ◽  
pp. 1-4
Author(s):  
Md Kamruzzaman Pramanik ◽  
Abdul Bathen Miah ◽  
Md Khorshed Alam
Keyword(s):  
Tensile Strength ◽  
Radiation Dose ◽  
Ionizing Radiation ◽  
Bacterial Count ◽  
B Value ◽  
Total Bacterial Count ◽  
Elongation At Break ◽  
Colour Parameter ◽  
60Co Source ◽  
L Value

The aim of the study was to preserve paper-based archived material for a long period of time using ionizing radiation/nuclear technique. To conduct this research, old note-pad samples were selected as tentative archived material. Samples were prepared and irradiated at a series of radiation doses e.g. 0, 2.0, 4.0, 6.0, 8.0, 10.0 and 14.0 kGy at a dose rate of 12.8 kGy/h from panaromic Batch type 80 kCi 60Co source. After irradiation, different quality parameters such as microbiological (Total Viable Bacterial Count, Total Fungal Count), mechanical (Tensile Strength, Percent of Elongation at Break and Elastic Modulus) and color properties (L-value, a-value and b-value) of the samples were assessed to observe the immediate effect of ionizing radiation on these properties. Results showed that the total bacterial count of unirradiated (control) paper were 4.0X102 cfu/g and radiation dose of 2.0 kGy was enough to eliminate the microbial load completely. Among mechanical properties, tensile strength (TS) of unirradiated sample was 16.23 MPa and it was gradually increased as the dose increased and finally reached upto 18.99 MPa at a dose of 14 kGy causing the TS-change above significant level (p < 0.05). Though changes of percent of elongation at break (EB) due to irradiation was insignificant, elastic module (EM) increased as the radiation dose increased gradually. EM of non irradiated sample was 381.85N/m2 and it started changing significantly from 6.0 kGy and finally reaches upto 477.03 N/m2 at 14.0 kGy. Results showed that L-value of colour parameter changed very slightly though a and b-value changed significantly from 6.0 kGy. From these findings it can be inferred that a radiation dose of 4.0 kGy might be used to conserve the cultural heritage including valuable paper-based archived materials. Bangladesh J Microbiol, Volume 33, Number 1-2, June-Dec 2016, pp 1-4

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