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1.
Acta Academiae Medicinae Sinicae ; (6): 454-463, 2023.
Artículo en Chino | WPRIM | ID: wpr-981291

RESUMEN

So far,the coronavirus disease 2019(COVID-19)has been persisting for nearly three years,infecting about 700 million people and causing more than 6 million deaths,which has seriously affected the human society.According to Global Initiative on Sharing All Influenza Data,there are more than 12 million SARS-CoV-2 variants,of which the five major variants of concern are Alpha,Beta,Gamma,Delta and Omicron.Their infectivity,pathogencity,and neutralization resistance have changed greatly compared with the original strain,which has brought great pressure to the prevention and control of the pandemic.Antibody level testing is critical for confirming infection,epidemiological investigation,vaccine development,and neutralizing drug preparation.Focusing on the humoral immunity against SARS-CoV-2,this paper introduces the mutation sites,neutralization resistance,and vaccination efficacy of the five variants of concern,and briefly summarizes the evolutionary characteristics,future mutation directions,and host immunity.


Asunto(s)
Humanos , SARS-CoV-2/genética , Formación de Anticuerpos , COVID-19 , Rayos gamma , Anticuerpos Neutralizantes , Anticuerpos Antivirales
2.
Biosci. j. (Online) ; 39: e39038, 2023. tab, graf
Artículo en Inglés | LILACS | ID: biblio-1428173

RESUMEN

Gum Arabic (Acacia nilotica L.) is a respected plant that has many nutrients and curative practices. It hinders, improves, or manages many disorders. The radio-protective activity of Acacia nilotica was investigated against γ-rays-induced testicle damage in rats. Twenty-four rats were correspondingly distributed into 4 groups; control, Acacia nilotica (15mg/kg, daily for 30 days), γ-irradiated (5Gy γ-rays, single dose) and Acacia nilotica plus γ-rays treated groups. The plasma testosterone and total antioxidant status (TAS) were estimated. Lipid peroxidation; malondialdehyde (MDA), reduced glutathione (GSH), malondialdehyde (MDA), superoxide dismutase (SOD), also glutathione peroxidase (GPx), catalase (CAT), tumor necrosis factor-α (TNF-α) with interleukin-1ß (IL-1ß), were determined in the testicle tissues. A testis weight, sperm count and motility, peripheral-blood and bone-marrow micronuclei (PMN and BMN), and frequency of chromosomal aberrations (CAs) were scored. A significant decline in the levels of plasma testosterone with TAS observed in the γ-irradiated rats. The results also showed significantly increased levels of testicle MDA, inflammatory markers, PMN, BMN and CAs frequencies and decrease in testes weight, sperm count and motility and levels of testicle antioxidants markers in gamma irradiated group. All these biochemical and fertility indices results were significantly enhanced in the Acacia nilotica plus γ-rays treated groups. However, the possible alleviate activity of Acacia nilotica on γ-rays-induced testicle injury in rats has not previously conversed, and this is the topic of this study.


Asunto(s)
Protectores contra Radiación , Ratas , Testículo/patología , Acacia , Rayos gamma
3.
Poblac. salud mesoam ; 19(2)jun. 2022.
Artículo en Español | LILACS, SaludCR | ID: biblio-1386957

RESUMEN

Resumen Introducción: el laboratorio de citogenética del Instituto de Investigaciones en Salud (INISA) de la Universidad de Costa Rica estableció un Servicio de Dosimetría Biológica en enero del 2020 utilizando biomarcadores citogenéticos de exposición a radiaciones ionizantes. Es el primero de su tipo en la región centroamericana. Objetivo: establecer un servicio de dosimetría biológica para Costa Rica, elaborando una curva de calibración dosis-efecto para rayos gamma. Metodología: para la realización de la curva de calibración se irradiaron muestras de sangre periférica in vitro con rayos gamma de dos voluntarios, uno femenino y otro masculino, en 11 puntos de dosis en el rango de 0 a 5 Gy. Se cultivó la sangre acorde a los protocolos internacionales durante 48 horas y se registraron las aberraciones inducidas. Los programas Dose Estimate V5.2 y R versión 4.03 se utilizaron para el cálculo de los coeficientes de la curva de calibración que correlaciona la frecuencia de cromosomas dicéntricos con la dosis. Resultados: los coeficientes de la curva son α: 0.02737±0.00658, ß: 0,05938±0,00450 y C: 0.00129±0.00084. Estos coeficientes tienen valores similares a los reportados internacionalmente. La curva se validó calculando dos dosis incógnitas, en la primera incógnita la dosis suministrada fue de 1,5 Gy y la dosis estimada fue 1,47 Gy y en la segunda la dosis suministrada fue de 4 Gy y la dosis estimada fue 3,616 Gy, para ambos casos no existen diferencias estadísticamente significativas entre las dosis suministradas y las estimadas. Conclusiones: actualmente El Servicio de Dosimetría Biológica del INISA puede estimar dosis absorbida en personas que se sospecha de una sobre exposición a rayos gamma en personal ocupacionalmente expuesto o personas involucradas en un accidente radiológico.


Abstract Introduction. The cytogenetics laboratory of the Health Research Institute (INISA) of the University of Costa Rica established a Biological Dosimetry Service in January 2020 using cytogenetic biomarkers of exposure to ionizing radiation. It is the first of its kind in the Central American region. Objective: establish a biological dosimetry service for Costa Rica, developing a dose-effect calibration curve for gamma rays. Methodology: to carry out the calibration curve, peripheral blood samples from two volunteers, one female and the other male, were irradiated in vitro with gamma rays, at 11 dose points in the range of 0 to 5 Gy. Blood was cultured according to international protocols for 48 hours and induced aberrations were recorded. The Dose Estimate V5.2 and R version 4.03 programs were used to calculate the coefficients of the calibration curve that correlates the frequency of dicentric chromosomes with the dose. Results: the coefficients of the curve are α: 0.02737 ± 0.00658, ß: 0.05938 ± 0.00450 and C: 0.00129 ± 0.00084. These coefficients have values similar to those reported internationally. The curve was validated by calculating two unknown doses, in the first unknown case the delivered dose was 1.5 Gy and the estimated dose was 1.47 Gy and in the second case the delivered dose was 4 Gy and the estimated dose was 3.616 Gy. for both cases there are no statistically significant differences between the delivered and estimated doses. Conclusions: the Biological Dosimetry Service of the INISA can estimate absorbed dose in persons suspected of overexposure to gamma rays in occupationally exposed personnel or persons involved in a radiological accident.Health is loaded with symbolisms and practical manifestations that differ according to social groups and sociocultural contexts. In order to make everyday life and needs visible, the Theoretical Paradigm of Social Representations provides the theoretical-methodological bases necessary to understand the common sense knowledge associated with health among the Nicaraguan migrant population in Costa Rica. Methodology: Qualitative study with ethnographic approach that aimed to identify the social representation of health, through the process of objectification, present among Nicaraguan migrants living in Costa Rica. Data collected through semi-structured interviews, participant observation, and field diaries. Processing according to Content Analysis. Results: The social representation of health found behaves analogously to a formula; where, the search for peaceful environments is added to the achievement of financial stability to result in two interdependent representations: 1) Health as physical-mental strength; and 2) Health as a future and abstract sensation of well-being, happiness and transcendence. The socio-political antecedents in Nicaragua, the migratory process, and the adaptation to Costa Rica play a preponderant role in shaping the representation on health. Conclusion: Social representations about health have direct practical implications on the ways of life and needs of migrant groups. Understanding their common sense knowledge allows to move towards more contextualized public policies. More integration of the thoughts, opinions and feelings of migrants in decision-making platforms is recommended.


Asunto(s)
Humanos , Masculino , Femenino , Radiación Ionizante , Dosimetría , Costa Rica , Rayos gamma
4.
Cuad. Hosp. Clín ; 62(1): 33-37, jun. 2021.
Artículo en Español | LILACS | ID: biblio-1284253

RESUMEN

INTRODUCCIÓN: el tiroides exhibe una gran avidez por el yodo radioactivo (I131) que al ser fijado por ésta glándula puede determinarse, desde afuera, aprovechando el hecho de que las radiaciones gamma atraviesan los tejidos blandos del cuello y pueden registrarse (Gammagrafía) a distancias apreciables. Desde 1962 Bolivia cuenta con esta tecnología, sin embargo, no cuenta con trabajos similares desde la declaración de país libre de enfermedades secundarias a la deficiencia de Yodo en 1997. El objetivo fue determinar valores de la captación tiroidea de I131 a las 24 horas en adultos jóvenes eutiroideos, residentes de gran altitud. MÉTODO: se realizó un estudio descriptivo transversal, en 76 sujetos obtenidos por intención y seleccionados mediante una entrevista clínica, examen físico dirigido y un consentimiento informado. El procedimiento fue ejecutado por personal calificado en el INAMEN siguiendo las recomendaciones de la OIEA. RESULTADOS: el valor de la captación tiroidea de I131 en 24 horas fue de 18,23 + 5,79% (rango 7,70 ­ 39,70). DISCUSIÓN: los expertos recomiendan establecer valores de referencia actualizados en cada región. Se han descrito variaciones de los valores normales influenciados por el sexo y edad; esta última, aparentemente por una hipofunción tiroidea inversamente proporcional con la edad. CONCLUSIÓN: el valor referencial encontrado en nuestro estudio es concordante con los establecidos en el extranjero, sin embargo, con una tendencia incrementada. Podría deberse a la secuencia cronológica de los estudios comparados en países que ya habían establecido políticas de yodación más tempranamente.


INTRODUCTION: the thyroid exhibits a great avidity for radioactive iodine (I131) which, when fixed by this gland, can be determined from the outside, taking advantage of the fact that gamma radiation passes through the soft tissues of the neck and can be registered (scintigraphy) at appreciable distances. Since 1962, Bolivia has had this technology, however, it does not have similar studies since the declaration of a country free of diseases secondary to iodine deficiency in 1997. The objective was to determine values of the thyroid uptake of I131 at 24 hours in euthyroid young adults, high altitude residents. METHOD: a descriptive cross-sectional study was carried out in 76 subjects obtained by intention and selected by means of a clinical interview, directed physical examination and informed consent. The procedure was carried out by qualified personnel at INAMEN, following IAEA recommendations. RESULTS: the value of the thyroid uptake of I131 in 24 hours was 18.23 + 5.79% (range 7.70 - 39.70). DISCUSSION: experts recommend establishing up-to-date reference values in each region. Variations in normal values influenced by sex and age have been described; the latter, apparently due to a thyroid hypofunction inversely proportional to age. CONCLUSION: the reference value found in our study is consistent with those established abroad, however, with an increased trend. It could be due to the chronological sequence of comparative studies in countries that had already established iodination policies earlier.


Asunto(s)
Humanos , Masculino , Femenino , Adulto , Estudios Transversales , Yodo , Glándula Tiroides , Rayos gamma , Consentimiento Informado
5.
An. Facultad Med. (Univ. Repúb. Urug., En línea) ; 8(1): e203, jun. 2021. tab, graf
Artículo en Español | LILACS, UY-BNMED, BNUY | ID: biblio-1248717

RESUMEN

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.


Asunto(s)
Animales , Saccharomyces cerevisiae/efectos de los fármacos , Saccharomyces cerevisiae/genética , Taninos/farmacología , Mutagénesis/efectos de los fármacos , Polifenoles/farmacología , Rayos gamma/efectos adversos , Protectores contra Radiación/farmacología , Tasa de Supervivencia , Quimioterapia Combinada , Tasa de Mutación
6.
Rev. cuba. invest. bioméd ; 40(supl.1): e1176, 2021. tab, graf
Artículo en Inglés | LILACS, CUMED | ID: biblio-1289469

RESUMEN

Nowadays, there is a growing interest in biodegradable polymers-based materials due to their diverse application in the biomedical field. Most studied systems involve biocompatible micro and nanodevices, such as liposomes, dendrimer, micelles or polymeric nanogels. The use of Radiation Technology, specifically gamma radiation, to produce micro and nanogels raises the possibility to obtain higher purity products, an important feature for biomedical and pharmaceutical applications. The radio-induced synthesis, characterization, cytotoxicity evaluation, and immunological response of nanogels are described in this study. Nanogel synthesis was performed in the absence of oxygen using aqueous polyvinylpyrrolidone solutions. Crosslinking reactions were carried out at 25 °C in a gamma irradiation chamber with a 60Co source. Nanogels properties were analysed by Scanning Electron Microscopy, Attenuated Total Reflection-Fourier Transform Spectroscopy, Dynamic Light Scattering, and Viscosimetry. The cytotoxicity and immunological response were evaluated by MTT test and analysis of the neutrophil respiratory burst. The results showed that nanogels formation strongly depends on the total absorbed dose. The nanogels have an elliptical shape and their chemical structure is similar to the initial polymer. The nanogels are biocompatible and promote a low-intensity neutrophil activation, similar to the well-characterized biomaterial TiO2, suggesting their potential biomedical uses(AU)


En la actualidad existe un interés creciente en los materiales biodegradables basados en polímeros, debido a sus diversas aplicaciones en la esfera de la biomedicina. En la mayoría de los sistemas estudiados participan micro- y nanodispositivos biocompatibles, tales como liposomas, dendrímeros, micelas o nanogeles poliméricos. El uso de la tecnología de radiaciones, en particular de radiaciones gamma, para producir micro- y nanogeles, eleva la posibilidad de obtener productos de mayor pureza, un rasgo importante con vistas a su aplicación biomédica y farmacéutica. El estudio describe la síntesis radioinducida, caracterización, evaluación de la citotoxicidad y respuesta inmunológica de los nanogeles. La síntesis de los nanogeles se realizó en ausencia de oxígeno, usando soluciones acuosas de polivinilpirrolidona. Las reacciones de entrecruzamiento se realizaron a 25 ºC en cámara de irradiación gamma con una fuente de 60Co. Las propiedades de los nanogeles se analizaron mediante microscopía electrónica de barrido, espectroscopia por transformada de Fourier total atenuada, dispersión dinámica de luz y viscosimetría. La citotoxicidad y la respuesta inmunológica se evaluaron mediante prueba MTT y análisis del estallido respiratorio de neutrófilos. Los resultados muestran que la formación de nanogeles depende en gran medida de la dosis total absorbida. Los nanogeles tienen forma elíptica y su estructura química es similar a la del polímero inicial. Los nanogeles son biocompatibles y promueven una activación de neutrófilos de baja intensidad similar al bien caracterizado material TiO2, lo que sugiere usos biomédicos potenciales(AU)


Asunto(s)
Humanos , Masculino , Femenino , Rayos gamma/uso terapéutico , Nanogeles/normas , Pruebas Inmunológicas de Citotoxicidad
7.
J. venom. anim. toxins incl. trop. dis ; 27: e20200140, 2021. graf, ilus
Artículo en Inglés | LILACS, VETINDEX | ID: biblio-1250256

RESUMEN

Tetanus toxin blocks the release of the inhibitory neurotransmitters in the central nervous system and causes tetanus and its main form of prevention is through vaccination. The vaccine is produced by inactivation of tetanus toxin with formaldehyde, which may cause side effects. An alternative way is the use of ionizing radiation for inactivation of the toxin and also to improve the potential immunogenic response and to reduce the post-vaccination side effects. Therefore, the aim of this study was to characterize the tetanus toxin structure after different doses of ionizing radiation of 60Co. Methods Irradiated and native tetanus toxin was characterized by SDS PAGE in reducing and non-reducing conditions and MALD-TOF. Enzymatic activity was measured by FRET substrate. Also, antigenic properties were assessed by ELISA and Western Blot data. Results Characterization analysis revealed gradual modification on the tetanus toxin structure according to doses increase. Also, fragmentation and possible aggregations of the protein fragments were observed in higher doses. In the analysis of peptide preservation by enzymatic digestion and mass spectrometry, there was a slight modification in the identification up to the dose of 4 kGy. At subsequent doses, peptide identification was minimal. The analysis of the enzymatic activity by fluorescence showed 35 % attenuation in the activity even at higher doses. In the antigenic evaluation, anti-tetanus toxin antibodies were detected against the irradiated toxins at the different doses, with a gradual decrease as the dose increased, but remaining at satisfactory levels. Conclusion Ionizing radiation promoted structural changes in the tetanus toxin such as fragmentation and/or aggregation and attenuation of enzymatic activity as the dose increased, but antigenic recognition of the toxin remained at good levels indicating its possible use as an immunogen. However, studies of enzymatic activity of tetanus toxin irradiated with doses above 8 kGy should be further analyzed.(AU)


Asunto(s)
Radiación Ionizante , Tétanos , Ensayo de Inmunoadsorción Enzimática , Rayos gamma , Toxina Tetánica , Cobalto
8.
Braz. j. biol ; 80(2): 465-473, Apr.-June 2020. graf
Artículo en Inglés | LILACS | ID: biblio-1132375

RESUMEN

Abstract This study was conducted to examine the effect of gamma radiation on biological specimens. Thus, our concept is to clarify that exposure to accumulated dose of 0.2 Gy gamma rays (0.66 rad/Sec. dose rate) from Cs137 source induces cellular perturbations in the midgut epithelium of the F1 progeny of Blaps polycresta, therefore affecting nutrition and growth. Beetles were reared in laboratory conditions and the newly emerged adults were irradiated with the aforementioned dose. Histological and ultrastructure anomalies of midgut cells (digestive and regenerative cells) were observed by 72 h after radiation exposure to ensure that the cells will not return to control state. Retardation in the development of the F1 progeny was also noticed and beetles died through two weeks. In the light of these observations, biological tissue act as an indicator to the continuous exposure to environmental radiation.


Resumo Este estudo foi conduzido para examinar o efeito da radiação gama em espécimes biológicos. Assim, nosso conceito é esclarecer que a exposição à dose acumulada de raios gama de 0,2 Gy (0,66 rad / seg. Dose) da fonte Cs137 induz perturbações celulares no epitélio do intestino médio da progênie F1 de Polycresta blaps, afetando a nutrição e crescimento. Besouros foram criados em condições de laboratório, e os adultos recém-emergidos foram irradiados com a dose acima mencionada. Anomalias histológicas e ultraestruturais das células do intestino médio (células digestivas e regenerativas) foram observadas 72 horas após a exposição à radiação, para garantir que as células não retornariam ao estado de controle. Retardo no desenvolvimento da progênie F1 também foi notado, e besouros morreram por duas semanas. À luz dessas observações, os tecidos biológicos atuam como um indicador para a exposição contínua à radiação ambiental.


Asunto(s)
Animales , Escarabajos , Contaminación Ambiental , Rayos gamma
9.
Electron. j. biotechnol ; 41: 81-87, sept. 2019. tab, graf, ilus
Artículo en Inglés | LILACS | ID: biblio-1087242

RESUMEN

Background: The search for innovative anti-tubercular agents has received increasing attention in tuberculosis chemotherapy because Mycobacterium tuberculosis infection has steadily increased over the years. This underlines the necessity for new methods of preparation for polymer-drug adducts to treat this important infectious disease. The use of poly(ethylene glycol)(PEG) is an alternative producing anti-tubercular derivatives. However, it is not yet known whether PEGylated isonicotinylhydrazide conjugates obtained by direct links with PEG are useful for therapeutic applications. Results: Here, we synthesized a PEGylated isoniazid (PEG-g-INH or PEG­INH) by gamma radiation-induced polymerization, for the first time. The new prodrugs were characterized using Raman and UV/Vis spectrometry. The mechanism of PEGylated INH synthesis was proposed. The in vitro evaluation of a PEGylated isonicotinylhydrazide macromolecular prodrug was also carried out. The results indicated that PEG­INH inhibited the bacterial growth above 95% as compared with INH, which showed a lower value (80%) at a concentration of 0.25 µM. Similar trends are observed for 0.1, 1, and 5 µM. Conclusions: In summary, the research suggests that it is possible to covalently attach the PEG onto INH by the proposed method and to obtain a slow-acting isoniazid derivative with little toxicity in vitro and higher antimycobacterial potency than the neat drug.


Asunto(s)
Polietilenglicoles/química , Isoniazida/química , Mycobacterium tuberculosis/efectos de los fármacos , Antituberculosos/química , Polietilenglicoles/farmacología , Polímeros , Espectrometría Raman , Técnicas In Vitro , Profármacos , Polimerizacion , Rayos gamma , Isoniazida/farmacología , Antituberculosos/farmacología
10.
Hig. aliment ; 33(288/289): 1045-1049, abr.-maio 2019. ilus
Artículo en Portugués | LILACS, VETINDEX | ID: biblio-1482096

RESUMEN

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.


Asunto(s)
Animales , Bovinos , Carne Roja/efectos de la radiación , Peroxidación de Lípido , Rayos gamma/efectos adversos , Dosis de Radiación , Sustancias Reactivas al Ácido Tiobarbitúrico
11.
Journal of Veterinary Science ; : 72-78, 2019.
Artículo en Inglés | WPRIM | ID: wpr-758881

RESUMEN

White blood cells (WBCs) and storage period are the main factors of transfusion reactions. In the present study, cytokine/chemokine concentrations after leukoreduction (LR) and irradiation (IR) in stored canine whole blood were measured. Red blood cell storage lesion caused by IR and LR were also compared. Blood samples from 10 healthy Beagles were divided into four groups (no treatment, LR-, IR-, and LR + IR-treated). Leukocytes were removed by filtration in the LR group and gamma radiation (25 Gy) was applied in the IR group. Immunologic factors (WBCs, interleukin-6 [IL-6], C-X-C motif chemokine ligand 8 [CXCL-8], and tumor necrosis factor-alpha) and storage lesion factors (blood pH, potassium, and hemolysis) were evaluated on storage days 0, 7, 14, 21, and 28. Compared to the treated groups, IL-6 and CXCL-8 concentrations during storage were significantly higher in the control (no treatment) group. LR did not show changes in cytokine/chemokine concentrations, and storage lesion presence was relatively mild. IR significantly increased CXCL-8 after 14 days of storage, but IR of leukoreduced blood did not increase CXCL-8 during 28 days of storage. Storage lesions such as hemolysis, increased potassium, and low pH were observed 7 days after IR and storage of blood, regardless of LR. IR of leukoreduced blood is beneficial to avoid immune reactions; however, storage lesions should be considered upon storage.


Asunto(s)
Conservación de la Sangre , Regulación hacia Abajo , Eritrocitos , Filtración , Rayos gamma , Hemólisis , Concentración de Iones de Hidrógeno , Factores Inmunológicos , Interleucina-6 , Procedimientos de Reducción del Leucocitos , Leucocitos , Necrosis , Potasio , Reacción a la Transfusión
12.
Journal of Experimental Hematology ; (6): 527-533, 2019.
Artículo en Chino | WPRIM | ID: wpr-771925

RESUMEN

OBJECTIVE@#To improve and establish the mouse model with aplastic anemia (AA) mediated by Cs γ-ray irradiation combined with cyclophosphamide (CTX) and chloramphenicol (CHL) injection,so as to provide a stable model for studying the pathogenesis and treatment of AA .@*METHODS@#The BALB/c mice were exposed to Cs γ-ray of 3-5 Gy(91 cGy/min) and were intraperitoneally injected with CTX of 25 mg/(kg.d) and CHL of 62.5 mg/(kg.d) at D 4,5 and 6 after irradiation; the WBC, platelet and reticulocyte counts in peripheral blood as well as the mucleated cell count in bone marrow and bone marrow smears were detected .@*RESULTS@#The 3-lineage cells in peripheral blood of BALB/c mouse model with acquired AA were rapidly reduced, especially WBC, platelet and reticulocyte counts were lowest at D 14,the 3-lineage cells in peripheral blood were still severely reduced at D 28; the nucleated cell count in bone marrow significantly dcreased,the bone marrow hyperplasia was reduced or severely reduced; the pathological sections of bone marrow showed the severe reduction of hematopoietic cells and the increased of non-hematopoietic cells such as fat cells.@*CONCLUSION@#The mouse model with acquired AA has been established by Cs γ-ray irradiation combined with CTX and CHL injection. All detection indicators of this model reach to diagnostic criteria for acquired AA,therefore this mouse model may be used as the model for study of pathogenesis and treatment of acquired AA.


Asunto(s)
Animales , Ratones , Anemia Aplásica , Cloranfenicol , Ciclofosfamida , Rayos gamma , Ratones Endogámicos BALB C
13.
Journal of Experimental Hematology ; (6): 2030-2034, 2019.
Artículo en Chino | WPRIM | ID: wpr-781499

RESUMEN

Abstract  With the development of transfusion medicine and the mastery of blood transfusion diagnosis and treatment techniques, the application of irradiated blood products in our country is gradually increasing. In recent years, the proportion of blood transfused by γ-rays has been increasing. In some foreign countries, the application rate of blood irradiated by radiotherapy is as high as 95%. At present, it is still in the promotion stage in China. This article summarizes the commonly used methods of blood irradiation, including the choice of irradiation source, the core dose and common irradiation targets, compares the difference of different irradiation methods, and generalizes the common application of blood irradiation. It is proposed that in addition to TA-GVHD application, blood irradiation may have a broad prospects for cancer therapy and microbial killing.


Asunto(s)
Humanos , Transfusión Sanguínea , China , Rayos gamma , Enfermedad Injerto contra Huésped
14.
Electron. j. biotechnol ; 35: 57-62, sept. 2018. tab, graf
Artículo en Inglés | LILACS | ID: biblio-1047773

RESUMEN

Background: Rubus is an economically important fruit crop across the globe. Recently, several Rubus mutant genotypes with improved agronomic traits have been developed using gamma ray irradiation. This study investigated genetic diversity and variations in Rubus mutant genotypes using single nucleotide polymorphism (SNP) markers generated from genotyping-by-sequencing (GBS) analysis. A GBS library of 14 Rubus genotypes, consisting of seven boysenberry mutant lines, four blackberry mutant lines, and three original varieties, were sequenced on the Illumina Hiseq2000 platform. A set of SNPs were analyzed by Kompetitive Allele Specific PCR (KASP) assay in order to discriminate the Rubus genotypes. Results: A total of 50,831,040 (86.4%) reads of clean data were generated, and the trimmed length ranged from 116,380,840 to 509,806,521 bp, with an average of 228,087,333 bp per line. A total of 19,634 high-quality SNPs were detected, which contained 11,328 homozygous SNPs and 8306 heterozygous SNPs. A set of 1504 SNPs was used to perform a phylogenetic analysis, which showed that there were clear differences among the Rubus genotypes based on their origin. A total of 25 SNPs were used for the KASP assays, of which six KASP primer sets were successfully distinguished among the Rubus genotypes. Conclusions: This study demonstrated that the SNP and KASP method is an economically efficient tool for mutant screening in Rubus breeding programs.


Asunto(s)
Polimorfismo de Nucleótido Simple/genética , Rubus/genética , Filogenia , Cruzamiento , Marcadores Genéticos , Productos Agrícolas , Alelos , Secuenciación de Nucleótidos de Alto Rendimiento , Rayos gamma , Genotipo , Mutación
15.
An. acad. bras. ciênc ; 90(1): 425-438, Mar. 2018. tab, graf
Artículo en Inglés | LILACS | ID: biblio-886888

RESUMEN

ABSTRACT This study evaluated the quality of heartwood and sapwood from mature trees of three species of Eucalyptus, by means of the qualification of their proportion, determination of basic and apparent density using non-destructive attenuation of gamma radiation technique and calculation of the density uniformity index. Six trees of each species (Eucalyptus grandis - 18 years old, Eucalyptus tereticornis - 35 years old and Corymbia citriodora - 28 years old) were used in the experimental program. The heartwood and sapwood were delimited by macroscopic analysis and the calculation of areas and percentage of heartwood and sapwood were performed using digital image. The uniformity index was calculated following methodology which numerically quantifies the dispersion of punctual density values of the wood around the mean density along the radius. The percentage of the heartwood was higher than the sapwood in all species studied. The density results showed no statistical difference between heartwood and sapwood. Differently from the density results, in all species studied there was statistical differences between uniformity indexes for heartwood and sapwood regions, making justifiable the inclusion of the density uniformity index as a quality parameter for Eucalyptus wood.


Asunto(s)
Madera/anatomía & histología , Eucalyptus/anatomía & histología , Rayos gamma , Control de Calidad , Gravedad Específica , Madera/análisis , Brasil
16.
Braz. j. med. biol. res ; 51(9): e7404, 2018. graf
Artículo en Inglés | LILACS | ID: biblio-951760

RESUMEN

DNA repair pathways, cell cycle checkpoints, and redox protection systems are essential factors for securing genomic stability. The aim of the present study was to analyze the effect of Ilex paraguariensis (Ip) infusion and one of its polyphenolic components rutin on cellular and molecular damage induced by ionizing radiation. Ip is a beverage drank by most inhabitants of Argentina, Paraguay, Southern Brazil, and Uruguay. The yeast Saccharomyces cerevisiae (SC7Klys 2-3) was used as the eukaryotic model. Exponentially growing cells were exposed to gamma rays (γ) in the presence or absence of Ip or rutin. The concentrations used simulated those found in the habitual infusion. Surviving fractions, mutation frequency, and DNA double-strand breaks (DSB) were determined after treatments. A significant increase in surviving fractions after gamma irradiation was observed following combined exposure to γ+R, or γ+Ip. Upon these concomitant treatments, mutation and DSB frequency decreased significantly. In the mutant strain deficient in MEC1, a significant increase in γ sensitivity and a low effect of rutin on γ-induced chromosomal fragmentation was observed. Results were interpreted in the framework of a model of interaction between radiation-induced free radicals, DNA repair pathways, and checkpoint controls, where the DNA damage that induced activation of MEC1 nodal point of the network could be modulated by Ip components including rutin. Furthermore, ionizing radiation-induced redox cascades can be interrupted by rutin potential and other protectors contained in Ip.


Asunto(s)
Rutina/farmacología , Saccharomyces cerevisiae/efectos de los fármacos , Saccharomyces cerevisiae/efectos de la radiación , Extractos Vegetales/farmacología , Antimutagênicos/farmacología , Ilex paraguariensis/química , Protección Radiológica/métodos , Espectrometría de Masas , ADN de Hongos/efectos de la radiación , Supervivencia Celular/efectos de los fármacos , Supervivencia Celular/efectos de la radiación , Células Cultivadas , Reproducibilidad de los Resultados , Cromatografía Liquida , Mutagénesis , Reparación del ADN , Relación Dosis-Respuesta en la Radiación , Roturas del ADN de Doble Cadena , Tasa de Mutación , Rayos gamma
17.
Biomedical Engineering Letters ; (4): 383-392, 2018.
Artículo en Inglés | WPRIM | ID: wpr-717985

RESUMEN

For prompt gamma ray imaging for biomedical applications and environmental radiation monitoring, we propose herein a multiple-scattering Compton camera (MSCC). MSCC consists of three or more semiconductor layers with good energy resolution, and has potential for simultaneous detection and differentiation of multiple radio-isotopes based on the measured energies, as well as three-dimensional (3D) imaging of the radio-isotope distribution. In this study, we developed an analytic simulator and a 3D image generator for a MSCC, including the physical models of the radiation source emission and detection processes that can be utilized for geometry and performance prediction prior to the construction of a real system. The analytic simulator for a MSCC records coincidence detections of successive interactions in multiple detector layers. In the successive interaction processes, the emission direction of the incident gamma ray, the scattering angle, and the changed traveling path after the Compton scattering interaction in each detector, were determined by a conical surface uniform random number generator (RNG), and by a Klein-Nishina RNG. The 3D image generator has two functions: the recovery of the initial source energy spectrum and the 3D spatial distribution of the source. We evaluated the analytic simulator and image generator with two different energetic point radiation sources (Cs-137 and Co-60) and with an MSCC comprising three detector layers. The recovered initial energies of the incident radiations were well differentiated from the generated MSCC events. Correspondingly, we could obtain a multi-tracer image that combined the two differentiated images. The developed analytic simulator in this study emulated the randomness of the detection process of a multiple-scattering Compton camera, including the inherent degradation factors of the detectors, such as the limited spatial and energy resolutions. The Doppler-broadening effect owing to the momentum distribution of electrons in Compton scattering was not considered in the detection process because most interested isotopes for biomedical and environmental applications have high energies that are less sensitive to Doppler broadening. The analytic simulator and image generator for MSCC can be utilized to determine the optimal geometrical parameters, such as the distances between detectors and detector size, thus affecting the imaging performance of the Compton camera prior to the development of a real system.


Asunto(s)
Vestuario , Rayos gamma , Isótopos , Monitoreo de Radiación , Semiconductores
18.
Biomedical and Environmental Sciences ; (12): 467-472, 2018.
Artículo en Inglés | WPRIM | ID: wpr-690633

RESUMEN

There is still a need for better protection against or mitigation of the effects of ionizing radiation following conventional radiotherapy or accidental exposure. The objective of our current study was to investigate the possible roles of matrix metalloproteinase inhibitor, ilomastat, in the protection of mice from total body radiation (TBI), and the underlying protective mechanisms. Ilomastat treatment increased the survival of mice after TBI. Ilomastat pretreatment promoted recovery of hematological and immunological cells in mice after 6 Gy γ-ray TBI. Our findings suggest the potential of ilomastat to protect against or mitigate the effects of radiation.


Asunto(s)
Animales , Ratones , Síndrome de Radiación Aguda , Sangre , Alergia e Inmunología , Células Sanguíneas , Efectos de la Radiación , Relación Dosis-Respuesta a Droga , Rayos gamma , Ácidos Hidroxámicos , Usos Terapéuticos , Indoles , Usos Terapéuticos , Inhibidores de la Metaloproteinasa de la Matriz , Usos Terapéuticos , Traumatismos Experimentales por Radiación , Sangre , Alergia e Inmunología , Protectores contra Radiación , Usos Terapéuticos , Bazo , Alergia e Inmunología , Efectos de la Radiación , Análisis de Supervivencia , Irradiación Corporal Total
19.
Braz. oral res. (Online) ; 32: e004, 2018. tab, graf
Artículo en Inglés | LILACS | ID: biblio-889501

RESUMEN

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.


Asunto(s)
Animales , Masculino , Ratones , Aloe/química , Rayos gamma/efectos adversos , Nanopartículas del Metal/uso terapéutico , Úlceras Bucales/tratamiento farmacológico , Úlceras Bucales/etiología , Traumatismos Experimentales por Radiación/tratamiento farmacológico , Plata/uso terapéutico , Ácido Acético , Actinas/análisis , Administración Tópica , Células Epiteliales/efectos de los fármacos , Células Epiteliales/efectos de la radiación , Fibroblastos/efectos de los fármacos , Inmunohistoquímica , Microscopía Electrónica de Transmisión , Úlceras Bucales/patología , Traumatismos Experimentales por Radiación/patología , Valores de Referencia , Reproducibilidad de los Resultados , Factores de Tiempo , Resultado del Tratamiento , Cicatrización de Heridas/efectos de los fármacos
20.
J. appl. oral sci ; 25(6): 657-665, Nov.-Dec. 2017. tab, graf
Artículo en Inglés | LILACS, BBO | ID: biblio-893675

RESUMEN

Abstract Objective: The purpose of this study was to compare laser with conventional techniques in class V cavity preparation in gamma-irradiated teeth. Methods: Forty extracted human teeth with no carious lesions were used for this study and were divided into two main groups: Group I (n = 20) was not subjected to gamma radiation (control) and Group II (n=20) was subjected to gamma radiation of 60 Gray. Standard class V preparation was performed in buccal and lingual sides of each tooth in both groups. Buccal surfaces were prepared by the Er,Cr:YSGG laser (Waterlase iPlus) 2780 nm, using the gold handpiece with MZ10 Tip in non-contact and the "H" mode, following parameters of cavity preparation - power 6 W, frequency 50 Hz, 90% water and 70% air, then shifting to surface treatment laser parameters - power 4.5 W, frequency 50 Hz, 80% water and 50% air. Lingual surfaces were prepared by the conventional high-speed turbine using round diamond bur. Teeth were then sectioned mesio-distally, resulting in 80 specimens: 40 of which were buccal laser-treated (20 control and 20 gamma-irradiated specimens) and 40 were lingual conventional high-speed bur specimens (20 control and 20 gamma-irradiated specimens). Results: Microleakage analysis revealed higher scores in both gamma groups compared with control groups. Chi-square test revealed no significant difference between both control groups and gamma groups (p=1, 0.819, respectively). A significant difference was revealed between all 4 groups (p=0.00018). Conclusion: Both laser and conventional high-speed turbine bur show good bond strength in control (non-gamma) group, while microleakage is evident in gamma group, indicating that gamma radiation had a dramatic negative effect on the bond strength in both laser and bur-treated teeth.


Asunto(s)
Humanos , Caries Dental/radioterapia , Preparación de la Cavidad Dental/métodos , Filtración Dental/radioterapia , Rayos gamma
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