Survey on the awareness and application of radiation shielding specifications for γ-ray radiotherapy room / 中国职业医学

Objective: To investigate the implementation of GBZ/T 201.3-2014 Radiation Shielding Specification for Radiotherapy Room--Part 3: Radiotherapy Room of γ-ray Sources (hereinafter referred to GBZ/T 201.3-2014). Methods: A total of 129 personnels, who were involved in the approval and supervision of radiation diagnosis and treatment construction projects in 19 provincial administrative agencies, engaged in radiation protection testing and evaluation of γ-ray radiotherapy rooms in radiation health technology service institutions, and used GBZ/T 201.3-2014 in other institutions (environmental impact assessment, education and scientific research), were selected as the participants using a stratified random sampling method. A questionnaire survey was conducted to assess their awareness and application of the standard. Results: The participants' awareness of GBZ/T 201.3-2014 was ≥63.6%, but the training rate was only 9.1% to 50.0%. The familiarity with the various chapters of the standard was over 86.4%. And 42.6% of the participants reported using the standard at least once a year. Regarding the applicability of the standard, all of the participants believed that the standard meets the needs of approval, supervision, testing, or evaluation, and adapts to the updated development of radiotherapy equipment and technology. And 94.6% of the participants believed that the use of the standard could improve the level of protection design and management, and 92.2% believed that the standard was widely applied. Regarding the adequacy of the standard, 97.7% of the participants believed that the standard's reference for ambient dose equivalent rate was reasonable, while 34.1% believed that the standard needs revision. Conclusion: The participants are satisfied with the standard and believe its applicability. They have a good level of awareness of the standard, but there is a room for improvement in their familiarity with the shielding calculation related content of the standard. The promotion, training, and practicality of the standard need to be strengthened.

Inicio de la Dosimetría Biológica en Costa Rica y su importancia en la atención de poblaciones sobreexpuestas a radiaciones / Beginning of Biological Dosimetry in Costa Rica and its importance in the care of populations overexposed to ionizing radiation

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.

Study on the efficacy and safety of FOLFOX4 regimen hepatic arterial infusion chemotherapy combined with 125I seed implantation in patients with primary liver cancer and type Ⅲ portal vein tumor thrombus / 中国医师进修杂志

Objective:To explore the efficacy and safety of FOLFOX4 regimen hepatic arterial infusion chemotherapy (HAIC) combined with 125I seed implantation or gamma knife in patients with primary liver cancer and type Ⅲ portal vein tumor thrombosis (PVTT). Methods:The clinical data of 116 patients with primary liver cancer and type Ⅲ PVTT from January 2016 to June 2018 in the Sixth Medical Center of PLA General Hospital were retrospectively analyzed. Among them, 56 patients were treated with FOLFOX4 regimen HAIC combined with 125I seed implantation in PVTT (observation group), and 56 patients were treated with FOLFOX4 regimen HAIC combined with gamma knife in PVTT (control group). The clinical efficacy, adverse reactions, liver function, tumor serum markers, quality of life and portal venous pressure were compared between 2 groups. The patients were followed up to June 2021, the progression-free survival (PFS) time, overall survival (OS) time and 1-, 3-year survival rate were recorded. Results:The objective response rate and disease control rate in observation group were significantly higher than those in control group: 21.43% (12/56) vs. 7.14% (4/56) and 50.00% (28/56) vs. 30.36% (17/56), and there were statistical differences ( P<0.05). The aspartate transaminase (AST), alanine transaminase (ALT), total bilirubin, alpha fetoprotein (AFP), carcinoembryonic antigen (CEA) and tumor supplied group of factor (TSG) after treatment in observation group were significantly lower than those in control group: (58.24 ± 7.16) U/L vs. (67.81 ± 8.39) U/L, (56.39 ± 5.42) U/L vs. (62.87 ± 6.83) U/L, (21.21 ± 4.32) μmol/L vs. (25.88 ± 4.71) μmol/L, (32.98 ± 6.15) μg/L vs. (45.06 ± 7.24) μg/L, (2.39 ± 0.22) μg/L vs. (3.17 ± 0.26) μg/L and (57.81 ± 5.67) kU/L vs. (66.19 ± 5.45) kU/L, and there were statistical differences ( P<0.01). The quality of life questionnaire core-30 (QLQ-C30) score after treatment in observation group was significantly higher than that in control group: (68.13 ± 6.95) scores vs. (64.49 ± 6.73) scores, the portal venous pressure after treatment in observation group was significantly lower than that in control group: (31.85 ± 3.89) cmH 2O (1 cmH 2O = 0.098 kPa) vs. (35.37 ± 4.23) cmH 2O, and there were statistical differences ( P<0.01). There was no statistical difference in incidence of adverse reactions between 2 groups ( P>0.05). Two cases were lost in observation group and 3 cases in the control group; the PFS time and OS time in observation group were significantly longer than those in control group: (13.36 ± 2.85) months vs. (11.76 ± 2.60) months and (23.36 ± 4.37) months vs. (20.72 ± 3.96) months, and there were statistical differences ( P<0.01); the 1-year survival rate in observation group was significantly higher than that in control group: 70.37% (38/54) vs. 50.94% (27/53), and there was statistical difference ( P<0.05); there was no statistical difference in 3-year survival rate between 2 groups ( P>0.05). Conclusions:The anti-tumor effect and the improvement effect on liver function in patients with primary liver cancer and type Ⅲ PVTT treated with FOLFOX4 regimen HAIC combined with 125I seed implantation are better than combined gamma knife, and it has high safety and longer survival time.

Characterization and evaluation of the enzymatic activity of tetanus toxin submitted to cobalt-60 gamma radiation

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)

Analytical methods for assessing changes induced by gamma exposure in an animal model

SUMMARY OBJECTIVE: Ionizing radiation can cause radio-induced changes in the cellular metabolome due to the breakdown of DNA bonds. Our goal was to find the early tissue response to radiation exposure supported by distinct analytical methods. METHODS: Histological analyses were performed on the organs extracted from rats to search for microscopic changes. The histological slides stained with hematoxyline-eosin (HE) were analyzed in magnification (40x). Subsequently, the tissues were subjected to mass spectrometry that allowed molecular analysis and DESI-MSI that generated the molecular image of lipids, assessing changes in intensities, especially in the brain. RESULTS: The histological analysis found nonspecific inflammatory changes; no areas of fibrosis, necrosis, or apoptosis were identified, suggesting non-morphological tissue alterations. However, the DESI-MSI images of brain lipids allowed the observation of many radio-induced changes in the lipid's intensities. CONCLUSIONS: No early radio induced histological or mass weight changes in the radiation exposed rats could be observed at 5 Gy. However, early changes in the molecular level were observed in the DESI-MSI images of the brain lipids. The DESI-MSI method proved to be efficient and relevant, allowing a regional molecular analysis of the tissues, expanding a new field of study that is still in its infancy: radiometabolomics.

RESUMO OBJETIVO: Radiação ionizante pode causar alterações no metaboloma celular devido à quebra de ligações no DNA. O objetivo deste trabalho foi evidenciar a resposta aguda tecidual induzida pela exposição da radiação ionizante. MÉTODOS: Análises histológicas foram realizadas nos órgãos extraídos de ratos para análise de alterações microscópicas. As lâminas histológicas coradas com hematoxilina eosina (HE) foram analisadas em aumento (40x). Posteriormente, os tecidos foram submetidos a espectrometria de massa, que permitiu análise molecular e o Desi-MSI que gerou imagem molecular de lipídios, identificando alterações na intensidade, principalmente no cérebro. RESULTADOS: As análises histológicas encontraram alterações inflamatórias inespecíficas, nem áreas de fibrose, necrose ou apoptose, sugerindo ausência de alterações morfológicas. As imagens de lipídios cerebrais obtidas por Desi-MSI permitiram observar as inúmeras alterações na intensidade nas seções teciduais do encéfalo. CONCLUSÕES: Alterações agudas radioinduzidas de massa do órgão e histológicas nos órgãos dos ratos expostos não puderam ser observadas a 5 Gy. Entretanto, mudanças em nível molecular foram observadas nas imagens de Desi-MSI dos lipídios cerebrais. O método Desi-MSI mostrou-se eficiente e relevante, permitindo a análise molecular regi-onal dos tecidos no SNC, expandindo um novo campo de estudo que ainda está em sua infância: a radiometaboloma.

Sciatic nerve injury after contact with a radioactive metal piece containing iridium-192 isotope

@#Gamma ray sources containing the iridium-192 isotope are widely used for industrial radiologic imaging. Irradiation causes biological damages and tissue injuries by the interaction of molecules in the body. The injury is correlated with the amount of energy absorbed. Peripheral nerves are more resistant to radiation injuries than other tissues because of their protected positions, low metabolic rates and low reproductive capabilities. We present here a 17-year-old male who had sciatic nerve denervation after handling a radioactive metal piece containing iridium-192 isotope that dropped accidentally from an industrial radiography machine. Although there are previous case reports of radiation injury after handling gamma ray projector inadvertently, this is the first case with sciatic nerve injury.

Radiation induced mutagen sensitivity and chlorophyll mutation frequency on sesame seeds

Aim: Effect of gamma irradiation on genomic disorder in sesame are scanty. The present study was undertaken to evaluate the mutagenic effects of gamma rays on different parameters in two popular cultivars of sesame, Roma and Tilottama. Methodology: Seeds of these two cultivars were irradiated with five doses of gamma rays: (250, 300, 350, 400, and 450 Gy) at BARC, Trombay and were sown (along with the un-irradiated control) during March 2015 in a split plot design with 3 replications keeping row to row and plant to plant distance at 30 cm and 10 cm, respectively to determine mutagen sensitivity with regard to pollen fertility (%), germination (%) and seedling height (cm), root-shoot length (cm), plant survival (%) at maturity in M1 generation. To study mutability, four to five capsules from each M1 plants in all the treatments were collected separately to give rise the M2 generation. Individual plant progeny rows were sown in M2 during March 2016. ID50 was determined by probit analysis for germination, shoot-root length and plant survival. Since the dose requirement for pollen fertility is very high, ID30 was calculated instead of ID50 value. Results: It was observed that with increasing doses of gamma rays, the response of all characters decreased significantly and followed a linear relationship in both varieties. The root system was more profound to gamma rays than the shoot. Chlorophyll mutations showed independent response to different doses of gamma rays as they occurred in random. The mutability of genotype Roma induced with different doses of gamma rays was higher than that of Tilottama. Interpretation: Due to saturation in the mutational actions, response of characters decreased with increase in gamma ray doses but magnitudes of effect differed between genotypes. The cultivar Tilottama was found to be more sensitive than Roma.

Alterations in Biomarkers Associated with Sterility in Pectinophora gossypiella (Saunders) Induced by Gamma Irradiation

ABSTRACT Nowadays, radiation technology is widely used to produce changes in Biosystems. The goal of this work is to determine the variation induced male Pectinophora gossypiella in gamma-irradiated as pupae using 50Gy and 150Gy. Comparing elements composition and DNA (using RAPD-PCR) between substerile 50Gy and the sterile dose 150Gy in P. gossypiella showed variation between them. Potassium (K) was the most abundant elements in unirradiated and irradiated males followed by magnesium (Mg). The percentage of heavy metals as copper, zinc, and cadmium concurrent with K was directly proportional to the radiation dose. While the percentage of Mg, Phosphorous and calcium decreased as the radiation dose increased. The results also revealed that some extra bands appeared and others disappeared, as a result of irradiation. The appearance of extra bands may be due to the repair mechanism of the irradiation damaged DNA. The banding patterns obtained and the dendrograms drawn on the basis of presence and absence of bands revealed that 150Gy irradiated pupae are more different from the unirradiated pupae than the 50Gy irradiated pupae. It was concluded that the sterile male technique could be used as a benefit tool in controlling P. gossypiella.

Contrastive study on the treatment of locally recurrent nasopharyngeal carcinoma with large segmentation gamma knife and large segmentation conformal retransmission radiotherapy / 中国医师进修杂志

Objective To compare the efficacy and adverse reactions of large segmentation gamma knife and large segmentation conformal retransmission radiotherapy for locally recurrent nasopharyngeal carcinoma. Methods One hundred and twenty- one patients with locally recurrent nasopharyngeal carcinoma from January 2009 to June 2012 were selected. The patients were divided into large segmentation conformal retransmission radiotherapy group (control group, 61 cases) and large segmentation gamma knife retransmission radiotherapy group (study group, 60 cases) according to the propensity score matching method. The radiation injury, quality of life, short-term efficacy and long-term efficacy were observed. Results In the recent radiation injury, the incidences of maxillofacial skin reaction and fatigue in study group were significantly higher than those in control group: 28.3％ (17/60) vs. 13.1％ (8/61) and 48.3％ (29/60) vs. 29.5％ (18/61), and there were statistical differences (P<0.05);there were no statistical differences in the incidences of dry mouth and oral mucosal injury between 2 groups (P>0.05). In the long-term radiation injury, the incidences of deafness and difficulty in opening mouth in study group were significantly lower than those in control group: 33.3％ (20/60) vs. 52.5％(32/61) and 58.3％ (35/60) vs. 73.8％ (45/61), the incidence of maxillofacial muscle fibrosis in control group was significantly higher than that in control group: 43.3％ (26/60) vs. 26.2％ (16/61), and there were statistical differences (P<0.05); there were no statistical differences in the incidences of dry mouth and radiation encephalopathy between 2 groups (P>0.05). In the actual long- term radiation injury, the incidences of dry mouth, deafness and difficulty in opening mouth in study group were significantly lower than those in control group: 66.7％ (40/60) vs. 86.9％ (53/61), 31.7％ (19/60) vs. 50.8％ (31/61) and 43.3％ (26/60) vs. 67.2％ (41/61), the incidence of maxillofacial muscle fibrosis in study group was significantly higher than that in control group: 41.7％ (25/60) vs. 23.0％ (14/61), and there were statistical differences (P<0.01 or <0.05); there was no statistical difference in the incidence of radiation encephalopathy between 2 groups (P>0.05). There were no significant differences in Karnofsky performance scale (KPS) score and body weight change before treatment and at the end of treatment, and at the end of treatment and 3 months after treatment between 2 groups (P > 0.05). For the short-term efficacy, the local control rates of 3, 6, 9 and 12 months after treatment in study group were significantly higher than those in control group: 75.0％ (45/60) vs. 54.1％ (33/61), 86.7％ (52/60) vs. 62.3％ (38/61), 90.0％ (54/60) vs. 67.2％ (41/61) and 91.7％ (55/60) vs. 68.9％ (42/61), and there were statistical differences (P<0.05). For long-term efficacy, there was no significant difference in the survival rates of 1, 2, 3, 4 and 5-year between 2 groups (P > 0.05). Conclusions Large-segment gamma knife and large-segment conformal reconstitution radiotherapy are effective for the short-term curative effect and long-term curative effect of locally recurrent nasopharyngeal carcinoma. They can reduce radiation damage and have better safety. Large segmentation gamma knife reconstitution radiotherapy is more advantageous in reducing the long- term radiation injury and improving the local control than large segmentation conformal retransmission radiotherapy.

Protective effects and possible mechanism of 12-O-tetradecanoylophorbol-13-decano-ate against acute intestinal radiation injury of mice / 军事医学

Objective To investigate the effect of 12-O-tetradecanoylophorbol-13-decanoate(TPD)on protection against acute intestinal radiation injury of mice and the possible mechanism.Methods Twenty female BALB/c mice aged 6-8 weeks were divided by random number table method into the control group and TPD groups(25,50,and 100 μg/kg). A radiation-damaged model of mice was irradiated by 10 Gy 60Co γ-rays,while the TPD groups were pretreated for 3 d with caudal vein injection before irradiation.The survival time of 20 days and the number of crypts at 3.5 days after irradiation were detected.Rat intestinal epithelial cells(IEC-6)were treated with 1 nmol/L TPD for 12 h before irradiation with 10 Gy 60Co γ-rays,and CCK-8 was used to detect the capability of cell proliferation at 0,1,2,3 and 4 d after irradiation. Results The mice in the control group survived for an average of 4.2 days,compared to 10 days in the optimal TPD group (100 μg/kg).The average number of crypts in the control group and the best TPD group was 11.0 ±1.3 and 35.1 ±1.9 respectively.The proliferation activity of IEC-6 was measured for four consecutive days.The average D value of the TPD groups was significantly higher than that of control.Conclusion TPD has a protective effect against acute intestinal radiation injury, and its protective mechanism may be achieved by promoting intestinal crypt cell proliferation and increasing the number of crypts in the intestine.

Mutation and fermentation optimization of Bacillus amyloliquefaciens for acetoin production / 生物工程学报

As a platform chemical, acetoin has a great potential of application in medicine and food industries. In order to improve the efficiency of acetoin production, Bacillus amyloliquefaciens was treated by atmospheric and room temperature plasma and gamma rays. Two-round screening was adopted for obtaining positive mutants, and the best mutant B. amyloliquefaciens H-5 produced acetoin up to 68.2 g/L in shake flask. Then, culture conditions were optimized in 5-L fermentor to enhance acetoin production. Finally, 85.2 g/L acetoin was produced by B. amyloliquefaciens H-5, which was increased by 26.8% compared with that of the original strain B. amyloliquefaciens FMME088. These results indicated that the high-producing strain can be obtained efficiently by compound mutagenesis, which has a promising prospect for commercial scale process.

Alterations in Biomarkers Associated with Sterility in Pectinophora gossypiella (Saunders) Induced by Gamma Irradiation

ABSTRACT Nowadays, radiation technology is widely used to produce changes in Biosystems. The goal of this work is to determine the variation induced male Pectinophora gossypiella in gamma-irradiated as pupae using 50Gy and 150Gy. Comparing elements composition and DNA (using RAPD-PCR) between substerile 50Gy and the sterile dose 150Gy in P. gossypiella showed variation between them. Potassium (K) was the most abundant elements in unirradiated and irradiated males followed by magnesium (Mg). The percentage of heavy metals as copper, zinc, and cadmium concurrent with K was directly proportional to the radiation dose. While the percentage of Mg, Phosphorous and calcium decreased as the radiation dose increased. The results also revealed that some extra bands appeared and others disappeared, as a result of irradiation. The appearance of extra bands may be due to the repair mechanism of the irradiation damaged DNA. The banding patterns obtained and the dendrograms drawn on the basis of presence and absence of bands revealed that 150Gy irradiated pupae are more different from the unirradiated pupae than the 50Gy irradiated pupae. It was concluded that the sterile male technique could be used as a benefit tool in controlling P. gossypiella.

Identification and analysis of exosomal miRNAs in human umbilical vein endothelial cells irradiated by 60 Co γ-rays / 军事医学

Objective To study the changes in miRNAs expression in the exosomes of human umbilical vein endothelial cells(HUVECs) after 60 Co γ-rays expose using microRNA(miRNA) chips and bioinformatics techniques so as to provide new clues to the mechanism of radiation-induced vascular tissue injury and its bystander effects.Methods HUVECs exosomes were collected in the control and 4 Gy irradiated cells by ultra-high-speed centrifugation,and further confirmed using transmission electron microscopy (TEM) and Western blotting of exosomes biomarkers.miRNA microarray was used to analyze miRNA expression profiles of exosomes and cells.Also,real-time quantitative PCR(qRT-PCR) was used to verify differentially expressed miRNAs,and the miRDB and TargetScan were performed to predict the target genes of the differentially expressed miRNAs.Bioinformatics analysis was performed using DAVID,KEGG and other online tools.Results Compared with the control exosomes from non-irradiated HUVECs,miRNA microarray analysis revealed that 5 up-regulated,and 13 down-regulated miRNAs were identified in the exosomes from HUVECs at 0.5 h after 4 Gy-irradiation,and 16 up-regulated and 5 down-regulated miRNAs at 2 h after 4 Gy-irradiation.Moreover,38 and 85 miRNAs were differentially expressed respectively in the HUVECs at 0.5 h and 2 h after radiation.The difference was statistically significant(P<0.01).The results of bioinformatics showed that these miRNAs might exert the radiation-induced bystander effect (RIBE) by regulating MAPK signal pathways,RAS and PI3K-Akt signal pathways.Conclusion The ionizing radiation injury significantly alters the components and expression levels of exosomal miRNAs,which play important roles in regulating the signal pathways in response to radiation.

Influence of Gamma-rays Radiation Sterilization on the Content and Fingerprint Chromatography of Effec-tive Constituents in Simiao Junyi Ointment / 中国药师

Objective:To explore the degradation effect of gamma-rays radiation sterilization on the effective constituents in Simiao Junyi ointment and study the changes of fingerprint chromatography before and after the sterilization to provide basis for the feasibility of gamma-rays radiation sterilization for Simiao Junyi ointment. Methods:The contents of tetrahydropalmatine and PNS ( Panax Notogin-seng saponins) in Simiao Junyi ointment were determined by HPLC, and the fingerprint chromatography was established. The content changes of tetrahydropalmatine and PNS in Simiao Junyi ointment before and after the gamma-rays radiation sterilization were compared among the same batch and various batches, and the relative retention time and relative peak area in the fingerprint chromatography were also compared. Results:The content of tetrahydropalmatine had no change basically before and after the gamma-rays radiation steriliza-tion(P >0. 05), and there was no change in the total content of PNS (P >0. 05). Comparing the HPLC fingerprint chromatography at 280 nm, the relative retention time had statistically significant change after the gamma-rays radiation sterilization ((P 0. 05). The number of characteristic peaks reduced by one, namely the C8 characteristic peak disappeared in the pasteurized chromatography, and the areas of C6, C9 and C14 peak decreased significantly, while that of C12 increased. Conclusion:Gamma-rays radiation sterilization have no notable effect on the content of tet-rahydropalmatine and PNS in Simiao Junyi ointment, it can be used for the sterilization of Simiao Junyi ointment.

Golgi dispersal in irradiated cells and the protective effect of vanillin derivatives / 军事医学

Objective To determine the Golgi dispersal in radiation damaged cells and the protective effect of vanillin derivatives.Methods Immunofluorescence, cell cycle analysis of flow-cytometry,Western blot,and clone formation were used.Results Immunofluorescence observation showed that the Golgi dispersal caused by 2 Gy 60 Coγ-ray was significantly increased in a dose-dependent manner in the range of 4-10 Gy as was demonstrated by the fact that the Golgi area was significantly increased. When the irradiated cells were treated with the radioprotective agent VND3207, a vanillin derivative,the Golgi dispersal induced by radiation was significantly reduced.The radiation-induced Golgi dispersal was also displayed in a pattern of time-course after irradiation in the HeLa cells, and persisted at least to 36 h post-irradiation. Cell cycle test results indicated that the Golgi dispersal was not associated with the G2/M arrest triggered by radiation-induced DNA damage response.VND3207 could promote cell survival by plate colony formation assay.Conclusion The Golgi dispersal can be caused byγ-ray irradiation in a dose-and time-dependent manner, and VND3207 can provide a good protection against radiation injury associated with inhibited Golgi dispersal.

Effect of hydrogen-rich water on lymphocyte gene expression profiles of beagle dogs receiving gamma ray irradiation / 第二军医大学学报

Objective To study the effect of hydrogen-rich water on lymphocyte gene expression of Beagle dogs exposed to gamma ray (γ ray) using GeneChip technology. Methods Male Beagle dogs were divided into control group, irradiation (IR) group and hydrogen-rich water treatment (HRW + IR) group. GeneChip technology was applied to screen the differentially expressed genes in peripheral blood lymphocyte exposed to 2. 0 Gy60Co γ ray for 6 h. Gene ontology (GO) and Kyoto encyclopedia of gene and genomes (KEGG) databases were used to analyze the bioinformatics of the differentially expressed genes, and real-time quantitative PCR was used to validate the results of GeneChip. Results We screened 4 730 differentially expressed genes with over 2-fold changes in IR group and 4 493 genes inHRW+IR group, and identified 1 606 co-differentially expressed genes in the IR and HRW + IR groups. GO terms of biological process, cellular component and molecular function in the IR group were ten, nine and three, respectively, and in HRW+IR group were fifteen, three and four, respectively. The differentially expressed genes were involved in 19KEGG pathways in the IR group, 24 KEGG pathways in HRW+IR group, and five KEGG pathways in both groups. The PCR results of two genes, selected to validate the GeneChip, were consistent with the GeneChip results. Conclusion Our results indicate that the effect of hydrogen-rich water on lymphocyte gene expression of γ ray-radiated Beagle dogs may involve changes of molecular function, cellular component and biological process, and activation of many signal pathways.

Study on radioprotection effects of clinoptilolite on sub-acute radiation-injured mice / 解放军医学杂志

Objective To study the protection effect of clinoptilolite (Cp) against radiation injury. Methods Forty-eight male BALB/c mice were randomly divided into 6 groups, namely normal control group (distilled water+sham irradiation) radiation control group (distilled water + irradiation), 300mg/kg 523 group (200mg/kg nilestriol 24h before irradiation and 100mg/ kg nilestriol 4h after irradiation), 56mg/kg Cp group (56mg/kg Cp + irradiation), 167mg/kg Cp group (167mg/kg Cp + irradiation) and 500mg/kg Cp group (500mg/kg Cp+irradiation). Seven days after the administration of the drug, all the mice but those from the normal control group were irradiated with γ-ray irradiation of137Cs in the dose of 4.0Gy, at the rate of 0.75Gy/min. All the mice were given the drug for 14 days after irradiation. RBC, WBC and PLT counts in peripheral blood, superoxide dismutases (SOD) activity, malondialdehyde (MDA) level, glutathione peroxidase (GSH-Px) level in blood serum, the content of deoxyribonucleic acid (DNA) and hematopoietic stem cells in bone marrow were determined. Results Compared with radiation control group, on 10th day after irradiation, RBC counts in peripheral blood of 56mg/kg Cp group and 167mg/kg Cp group were significantly higher (P<0.05, P<0.0l), and WBC counts in peripheral blood of S6mg/kg Cp group and 500mg/kg Cp group were significantly higher (P<0.0l). On 14th day after irradiation, compared with radiation control group, the SOD activities in blood serum of three Cp groups were elevated (P<0.05, P<0.01) the GSH-Px levels were elevated in blood serum of 167mg/kg Cp group and 500mg/kg Cp.

Lasers in Operative Dentistry-A Review

Laser equipment represents surely one of the most captivating technologies in the practice of dental medicine. Over the last two decades, numerousscientific publications have emerged in literature, concerning laser equipments and their applications in the field of dental medicine. Presently, in accordancewith their specific wavelength, laser equipments are available on a large scale. This material reviews the most common, most current newly emerged applications of laser in dental medicine. The applications of laser therapy are presented on soft as well as hard tissues. Although laser cannot fully replace all the conventional techniques of dental medicine, the progress is obvious, and laser is expected to become an essential component of conservatory dental medicine.

amma Radiation: Physical Elicitor for In vitro Culture Techniques of Cajanus cajan.

Gamma rays are very important in mutation breeding and in in vitro mutagenesis in order to develop required features of plants and increase the genetic variability. Cajanus cajan when subjected to absorbed doses 30 Gy, 50 Gy, 100 Gy, 150 Gy and 200 Gy showed a direct corelation between callus induction, regeneracy frequency and absorbed doses of gamma radiation as compared to control. Gamma irradiation resulted in the induction of autonomous growth in callus, which led to the formation of callus tumors resembling the shape of crown gall tumors. Gamma irradiation in the present study proved to be an important tool in increasing the breeding efficiency, and regeneration frequency, especially that of the recalcitrant varieties.

Protective effects of different doses of hydrogen-rich water on radiation injury in mice / 中华放射医学与防护杂志

Objective To observe the protective effects of different doses of hydrogen-rich water on radiation injury in mice,so as to provide scientific basis for the application of hydrogen-rich water.Methods The ICR mice were randomly divided into control group,irradiation group,amifostine group and hydrogen-rich water of low,medium and high dose groups.The 30 days survival rate,body weight,hematology parameters,serum biochemical parameters,organ weight and coefficient,bone marrow micronucleus rate,bone marrow nucleated cell count were observed after total body irradiation with 9.0 Gy gamma rays.Results After 30 d of irradiation,the hydrogen-rich water showed obvious protective effect on the survival rate and body weight in a dose dependent manner so that the survival was significantly higher than that of irradiation group (t =-2.67,P ＜ 0.05).The biochemical index,such as TP,ALB and CRE in the low dose group,TP,ALB,TBIL and CRE in the medium dose group,and TP,ALB,GLU,TBIL,BUN,GRE and UA in the high dose group also indicated the protective effects of hydrogen-rich water (t =-2.04--4.11,P ＜ 0.05).But the protective effect of hydrogen-rich water was not observed in hematology,organ weight and coefficient,and bone marrow micronucleus induction.Conclusions The hydrogen-rich water has anti-radiation effect,which may depend on the dose of hydrogen.