Chronic Injury of Mice Bone Marrow Multipotent Hematopoietic Progenitor Cells Induced by Ionizing Radiation / 中国实验血液学杂志

OBJECTIVE@#To explore the chronic injury and its possible mechanism of ionizing radiation on multipotent hematopoietic progenitor cells (MPPs) by determining the related indicators of MPPs in bone marrow of mice post-radiation.@*METHODS@#Sixteen C57BL/6 adult mice were randomly divided into normal control and irradiation groups, 8 mice in each group. The mice in irradiation group were exposed to 6 Gy X-ray. The proportion of bone marrow MPPs, their apoptosis and proliferation 2 months after irradiation were detected by flow cytometry. Mitochondrial activity and levels of reactive oxygen species (ROS) in each MPPs population were detected by Mitotracker Red and DCFDA probes, and the senescent state of MPPs in the bone marrow was analyzed.@*RESULTS@#Ionizing radiation could reduce the proportion of MPPs in mouse bone marrow. The proportions and numbers of MPP1, MPP3 and MPP4 in the bone marrow were significantly decreased after whole-body irradiation with 6 Gy X-ray (P<0.05). In addition, radiation significantly reduced the colony-forming capacity of MPPs in bone marrow (P<0.05), the proportions of apoptotic cells in the MPP1 and MPP4 cell populations increased significantly in the bone marrow (P<0.05). The activity of mitochondria was significantly reduced in the bone marrow MPP2, MPP3 and MPP4 cell populations compared with that of the control group (P<0.05). It was also found that the radiation could significantly increase the ROS levels of MPPs in bone marrow, and the content of ROS in the MPP2, MPP3 and MPP4 cell population of the bone marrow was significantly increased(P<0.05). The senescent cells ratios of MPP1, MPP3 and MPP4 cells in the bone marrow after irradiation were significantly higher than those in the control group (P<0.05).@*CONCLUSION@#Ionizing radiation can cause chronic MPPs damage in mice, which is closely associated with persistent oxidative stress, cells apoptosis, and cellular senescence.

Radiación y medios de contraste en embarazo y lactancia: lo que el clínico necesita saber / Radiation and contrast media in pregnancy and lactation: what the clinician needs to know

Introducción: el uso de técnicas de imagenología es habitual e incluso indispensable en algunos procesos diagnósticos. Sin embargo, su indicación en mujeres embarazadas y en período de lactancia es controvertida. Objetivo: presentar una revisión narrativa sobre los riesgos asociados al uso de imágenes con radiación y medio de contraste en embarazo y periodo de lactancia, con énfasis en las recomendaciones y aplicaciones clínicas que el médico tratante debe tener presente al momento de su indicación. Métodos: se realizó una revisión bibliográfica de la literatura relevante sobre los riesgos y consideraciones especiales del uso de medios de contraste en el embarazo y lactancia. Resultados: los riesgos de la radiación ionizante sobre el feto varían de acuerdo al estadio del embarazo, por lo que la indicación del estudio debe ponderar los riesgos y beneficios. En las dosis clínicas en embarazo y lactancia, el uso de contraste yodado como basados en gadolinio no tienen efectos deletéreos en la salud de la madre ni la del feto. Sin embargo, las sociedades internacionales recomiendan limitar su uso. Conclusión: si bien la indicación de estudios de imagen que utilizan radiación ionizante en el embarazo y lactancia es seguro, el médico clínico debe conocer los posibles riesgos de la radiación ionizante en este grupo de pacientes. Respecto a los medios de contraste, el único efecto adverso reportado es la disfunción tiroidea transitoria en hijos de madres que recibieron medios de contraste yodado.

Introduction: the use of imaging techniques is essential in some diagnostic processes. However, its indication in pregnant and lac-tating women is controversial. Objective: To present a narrative review of the risks associated with using images with radiation and contrast media in pregnancy and lactation. Emphasis will be put on the recommendations and clinical applications that the physician must consider before its indication. Methods: a bibliographic review of the relevant literature on the risks and special considerations of contrast media in pregnancy and lactation was performed. Results: the risks of ionising radiation on the fetus vary according to the stage of pregnancy, so the indication of the study must balance the risks and benefits. The use of iodinated and gadolinium-based con-trast agents in clinical doses in pregnancy and lactation has no effects on the health of the mother or the fetus. However, international societies recommend limiting its use. Conclusion: Although the indication for imaging studies using ionising radiation in pregnancy and lactation is safe, the clinician must be aware of the possible risks of ionising radiation in this group of patients. The only adverse effect reported is transient thyroid dysfunction in children of mothers who received iodinated contrast media.

Perception of Orthopedics Surgeons about the Risks of Radiation Exposure in Fluoroscopy / Percepção de cirurgiões ortopédicos sobre os riscos da exposição à radiação na fluoroscopia

Abstract Objective The present study aims to understand the perceptions of orthopedists and traumatologists regarding the risk of exposure to ionizing radiation in fluoroscopy procedures. Methods An objective, structured, self-administered questionnaire with sociodemographic, professional, and occupational variables was developed, available through an invitation sent to orthopedist physicians whose contacts were made publicly available. Results A total of 141 questionnaires were answered and analyzed. Most respondents (99%) use fluoroscopy in their surgeries, and only 34.8% of the participants feel safe with the use of the equipment. It was observed that the knowledge about ionizing radiation is inadequate, because 22.6% of the participants are unaware of the type of radiation emitted in fluoroscopy and its biological effects. In addition, 52% of the participants did not know or do not understand the principles of radiological protection and their relationship with surgical practices. Conclusion We concluded that the radiological protection of most orthopedists in surgical procedures is inadequate, and initial and continued training programs of professionals are necessary, bringing health benefits to orthopedists and their patients.

Resumo Objetivo Este estudo visa compreender as percepções dos médicos ortopedistas e traumatologistas em relação ao risco da exposição à radiação ionizante nos procedimentos de fluoroscopia. Métodos Desenvolveu-se um questionário objetivo, estruturado, autoaplicável e com variáveis sociodemográficas, profissionais e ocupacionais, disponibilizado através de convite enviado a médicos ortopedistas cujos contatos estavam disponibilizados publicamente. Resultados Foram respondidos e analisados 141 questionários. A maioria dos respondentes (99%) utilizam a fluoroscopia em suas cirurgias, e apenas 34,8% dos participantes se sentem seguros com o uso do equipamento. Observou-se que o conhecimento sobre radiação ionizante é inadequado, pois 22,6% dos respondentes desconhecem o tipo de radiação emitida na fluoroscopia e seus efeitos biológicos. Além disso, 52% dos respondentes não conhecem ou não compreendem os princípios de proteção radiológica e suas relações com as práticas cirúrgicas. Conclusão Conclui-se que a proteção radiológica da maioria dos ortopedistas nos procedimentos cirúrgicos é inadequada e são necessários programas de formação inicial e continuada dos profissionais, trazendo benefícios para a saúde dos ortopedistas e de seus pacientes.

Reflexiones sobre los valores éticos de la protección radiológica para los profesionales tecnólogos médicos de imagenología / Reflections on the ethical values of radiation protection for the professional medical technologists in imaging

Las radiaciones ionizantes tienen el potencial de generar efectos adversos a la salud de las personas. Para hacer un uso más seguro y eficiente de estas radiaciones, la Comisión Internacional de Protección Radiológica fundamentalmente ha implementado un sistema de protección radiológica (SPR) que se basa en tres principios: justificación, optimización y límites. A su vez, estos principios se sustentan en cuatro valores éticos (beneficencia, prudencia, justicia y dignidad). Se sabe que en Chile el profesional que esta mandatado para realizar la toma de los exámenes que utilizan radiaciones ionizantes es el/la Tecnólogo Médico en Imagenología. Por lo tanto, resulta interesante valorar el grado de conocimiento adquirido y posteriormente aplicado en torno a los valores éticos del SPR por parte de dichos profesionales. De esta manera el objetivo del este artículo de tipo Punto de Vista fue realizar una serie de reflexiones en torno a esta temática. Cuando se realiza un procedimientos médico u odontológico con radiaciones ionizantes, el/la Tecnólogo Médico en Imagenología participa esencialmente en la realización del mismo, por lo que no debería ser su responsabilidad el cautelar que se cumplan los 4 valores éticos descritos dentro del SPR. A juicio nuestro, el principio de optimización, sería el único principio o pilar del SPR donde tiene real obligación de participar, utilizando las restricciones a las exposiciones individuales y los niveles de referencia para diagnóstico para reducir las desigualdades en la distribución de las exposiciones entre los grupos expuestos. Finalmente, resulta vital investigar si en su formación de especialidad se tocan estas temáticas

Ionizing radiation has the potential to generate adverse effects on people's health. To make safer and more efficient use of these radiations, the International Commission on Radiological Protection has fundamentally implemented a radiological protection system (RPS) based on three principles: justification, optimization and limits. In turn, these principles are based on four ethical values (beneficence, prudence, justice and dignity). It is known that in Chile the professional who is mandated to perform the exams that use ionizing radiation is the Medical Imaging Technologist. Therefore, it is interesting to assess the degree of knowledge acquired and subsequently applied around the ethical values of the RPS by these professionals. In this way, the objective of this Point of View article was to make a series of reflections on this subject. When a medical or dental procedure is performed with ionizing radiation, the Medical Imaging Technologist essentially participates in its performance, so it should not be their responsibility to ensure that the 4 ethical values described in the RPS are met. In our opinion, the principle of optimization would be the only principle or pillar of the RPS where it has a real obligation to participate, using the restrictions on individual exposures and the diagnostic reference levels to reduce inequalities in the distribution of exposures between exposed groups. Finally, it is vital to investigate whether these topics are addressed in his specialty training.

Consentimiento informado en radiología odontológica: un asunto pendiente / Informed consent in dental radiology: a pending matter

Introducción: En el ámbito odontológico es muy común el uso de radiografías intraorales, extraorales e incluso de tomografías computarizadas volumétricas. Las radiografías intraorales presentan una baja dosis de radiación en comparación con las tomografías computarizadas volumétricas que pueden emitir una mayor dosis de radiación con cierto grado de riesgo para los pacientes. A pesar de que se conoce sobre la importancia del uso del consentimiento informado y los riesgos durante estos procedimientos, muy poco se ha reportado sobre la utilización del consentimiento informado en radiología oral y maxilofacial. Objetivo: Analizar los beneficios y los retos de usar el consentimiento informado en radiología odontológica. Comentarios principales: Actualmente, no existe un consenso claro en la comunidad odontológica sobre si se debe obtener el consentimiento informado del paciente antes de que se someta a un examen de imagen con radiación ionizante. Su aplicación de manera repetitiva o prolongada podría afectar al paciente a largo plazo. Consideraciones globales: Existe un consenso universal en resaltar la importancia del consentimiento informado en todo el ámbito de la salud. Sin embargo, en la práctica, su realización puede conllevar ciertas dificultades, tales como la identificación del responsable de su realización, el tiempo que lleva ejecutarla y la preocupación por causar un miedo innecesario en el paciente. Si estas dificultades logran ser superadas, podremos ver los beneficios de tener un consenso claro para la utilización de un consentimiento informado en el área odontológica(AU)

Introduction: In the dental field, the use of intraoral, extraoral and even volumetric computed tomography is very common. Intraoral X-rays have a low dose of radiation compared to volumetric CT scans that can emit a higher dose of radiation with some degree of risk to patients. Although the importance of the use of informed consent and the risks during these procedures are known, very little has been reported about the use of informed consent in oral and maxillofacial radiology. Objective: Analyze the benefits and challenges of using informed consent in dental radiology. Main Comments: Currently, there is no clear consensus in the dental community on whether the patient's informed consent should be obtained before they undergo an imaging examination with ionizing radiation. Its application repetitively or prolongedly could affect the patient in the long term. Global considerations: There is a universal consensus to highlight the importance of informed consent in the entire field of health. However, in practice, its realization can lead to certain difficulties, such as the identification of the person responsible for its implementation, the time it takes to execute it and the concern to cause unnecessary fear in the patient. If these difficulties can be overcome, we can see the benefits of having a clear consensus for the use of informed consent in the dental area(AU)

Ensayo de micronúcleos con bloqueo de la citocinesis como biomarcador de daño genético en poblaciones sobreexpuestas a radiaciones ionizantes / Micronucleus assay as biomarker of DNA damage in population exposed to ionizing radiation

Resumen Introducción: las radiaciones ionizantes (RI) son capaces de perjudicar el ADN; para evaluar este fenómeno es posible utilizar la formación de micronúcleos como biomarcador de efecto temprano del daño radioinducido. El ensayo de micronúcleos con bloqueo de la citocinesis (MNBC) es una técnica citogenética que permite demostrar el impacto de agentes genotóxicos. Propósito: en el presente trabajo se describieron mecanismos moleculares involucrados en la radioinducción de micronúcleos, la técnica del MNBC, los criterios de análisis, sus aplicaciones dentro de la investigación biológica y su extensión a la clínica, con énfasis en su empleo como biomarcador del daño genético en grupos sobreexpuestos a RI. Argumentos para la discusión: el MNBC se considera un método confiable, simple y rápido y existe evidencia de su aplicabilidad para el estudio de los efectos biológicos en casos de riesgo ocupacional y en accidentes radiológicos aislados o a gran escala. Conclusiones: el MNBC es una herramienta valiosa que posibilita estimar las consecuencias por dosis bajas de RI en poblaciones involucradas y, a la vez, orientar la toma de decisiones en cuanto a su prevención o atenuación . De igual forma, puede ser utilizado en análisis del campo de la radiobiología, a fin de detallar las incidencias de las radiaciones ionizantes sobre el ADN.

Abstract Introduction. Ionizing radiation (IR) is capable of causing DNA damage. For the evaluation of this phenomenon it is possible to use chromosomal aberrations as biomarkers. The Cytokinesis-Block Micronucleus assay (CBMN) is a cytogenetic technique that allows to demonstrate the effect of genotoxic agents.Proposition:in the present review, we will describe the molecular mechanisms involved in micronucleus radioinduction, the micronucleus technique and criteria for analysis, its applications within biological research and its extension in clinical research, with emphasis on its application as a biomarker of radioinduced genetic damage. Arguments for discussion: the CBMN is considered a reliable, simple and fast technique and there is evidence of its applicability in the evaluation of biological effects in occupationally exposed personnel and in isolated or large-scale radiological accidents. Conclusions: the CBMN a valuable tool in estimating radiological risk in populations exposed to low doses of IR, allowing to guide decision-making regarding prevention or mitigation of exposure to IR in populations involved. Similarly, the cbmn can be used in research in the field of radiobiology, as a means to describe the effects of ionizing radiation on DNA.

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.

Evaluating pinhão conservation by using ionizing radiation and refrigeration

Pinhão is highly perishable due to its high water activity, being easily affected by fungi during storage and also susceptible to infestation by larvae. This seed is usually marketed in the pinhão cones itself, or bulk threshed, and packed in plastic bags, chilled or ground frozen. Pinhão conservation and industrialization techniques should be developed to promote its commercialization and consumption at other times of the year, besides the seasonal period, encouraging its sustainable production, extraction and commercialization, considering its essentially extractive character. The objective of this study was to evaluate the conservation of pinhão by the use of gamma radiation and refrigeration. The pinhões were irradiated with a cobalt­60 source at a dose rate of 1 kGy. A non-irradiated sample was used as a control. The pinhões were packed in high-density polyethylene bags and stored at ambient temperature and refrigerated at 4 ºC, during 90 days. Pinhões were evaluated for weight loss, acidity, reducing sugars, vitamin C, firmness, color, total phenolic compounds, antioxidant activity and microbiological analyzes. The isolated use of gamma radiation was not effective for the maintenance of the evaluated parameters. However, when used in conjunction with refrigerated storage, it reduced the growth of aerobic fungi, as well as mesophilic and psychrotrophic microorganisms. The isolated use of refrigeration showed a reduction in weight loss, reducing sugars and an increase in vitamin C content and antioxidant activity. Thus, to increase the benefits, we suggest evaluating higher doses of radiation as a function of the thick pinhão shell.

Reflexiones sobre el primer programa de magister en física médica en diagnóstico por imagen de Chile / Reflections on the first master's degree on physics in diagnostic imaging from Chile

El objetivo del presente artículo de actualización será dar a conocer el nuevo programa de postgrado desarrollado denominado Magíster en Física Médica en diagnóstico por imagen, describiendo sus principales características y proponiendo algunas reflexiones. Este programa tiene la particularidad de permitir el acceso a diferentes Licenciados provenientes de las áreas de la Salud, Ingenierías o Ciencias. El plan de trabajo para este programa es de dos años, contempla cuatro semestres, con 91 créditos transferibles (SCT) por concepto de cursos y 27 SCT dedicados a la tesis. Dando un total de 118 SCT. Los Físicos Médicos son profesionales con formación académica de postgrado y entrenamiento clínico, que forman parte del grupo multidisciplinario profesional responsable del diagnóstico y tratamiento de pacientes, garantizando la calidad de los aspectos técnicos que intervienen en los procesos, la efectividad y la seguridad de los mismos, reduciendo así la probabilidad de accidentes. El programa de Magíster en Física Médica en diagnóstico por imagen de la Universidad de Tarapacá abre sus puertas para profesionales que se interesen a recibir esta formación única en Chile y ayudar en la tarea de hacer cada día del diagnóstico por imagen, una actividad más segura para los pacientes, profesionales y el público en general.

The main objective of this updating article is to present the latest Post-graduated developed program named " Master in Medical Physics in image diagnosting", describing its main characteristics and proposing some reflections about it. This program is focused on different graduates from the Health, Engineering or Science field. The study plan for this program is two years, including four semesters with 91 transferable credits for courses and 27 SCT dedicated to the thesis with a total of 118 SCT. Medical Physicists are professionals with postgraduate academic and clinical training, which is part of the professional multidisciplinary group that is responsible for the diagnosis and treatment of patients, guaranteeing the quality of the technical areas involved in the processes, the effectiveness and safety, and reducing the probability of accidents. This program of "Universidad de Tarapaca" is open to professionals that are interested in receiving unique training in Chile and in helping to provide accurate and safe imaging diagnosis to patients on a daily basis.

Utility of melatonin in mitigating ionizing radiation-induced testis injury through synergistic interdependence of its biological properties

BACKGROUND: Ionizing radiations (IR) have widespread useful applications in our daily life; however, they have unfavorable effects on reproductive health. Maintaining testicular health following IR exposure is an important requirement for reproductive potential. The current study explored the role of melatonin (MLT) in mitigating IR-induced injury in young adult rat testis. METHODS: Rats were given daily MLT (25 mg/kg) for 3 and 14 days after receiving 4 Gy γ-radiation. RESULTS: Serum MLT levels and other antioxidants, including glutathione content, and the activity of glutathione peroxidase and glutathione reductase in the testis of the irradiated rats were remarkably maintained by MLT administration in irradiated rats. Hence, the hydrogen peroxide level declined with remarkably reduced formation of oxidative stress markers, 4-hydroxynonenal, and 8-Hydroxy-2'-deoxyguanosine in the testis of irradiated animals after MLT administration. The redox status improvement caused a remarkable regression of proapoptotic protein (p53, Cyto-c, and caspase-3) in the testis and improved inflammatory cytokines (CRP and IL-6), and anti-inflammatory cytokine (interleukin IL-10) in serum. This is associated with restoration of disturbed sex hormonal balance, androgen receptor upregulation, and testicular cell proliferation activity in irradiated rats, explaining the improvement of sperm parameters (count, motility, viability, and deformation). Consequently, spermatogenic cell depletion and decreased seminiferous tubule diameter and perimeter were attenuated by MLT treatment post irradiation. Moreover, the testis of irradiated-MLT-treated rats showed well-organized histological architecture and normal sperm morphology. CONCLUSIONS: These results show that radiation-induced testicular injury is mitigated following IR exposure through synergistic interdependence between the antioxidant, anti-inflammatory, anti-apoptotic, and anti-DNA damage actions of MLT.

Inhibition of Ciliogenesis Enhances the Cellular Sensitivity to Temozolomide and Ionizing Radiation in Human Glioblastoma Cells / 生物医学与环境科学（英文）

Objective@#To investigate the function of primary cilia in regulating the cellular response to temozolomide (TMZ) and ionizing radiation (IR) in glioblastoma (GBM).@*Methods@#GBM cells were treated with TMZ or X-ray/carbon ion. The primary cilia were examined by immunostaining with Arl13b and γ-tubulin, and the cellular resistance ability was measured by cell viability assay or survival fraction assay. Combining with cilia ablation by IFT88 depletion or chloral hydrate and induction by lithium chloride, the autophagy was measured by acridine orange staining assay. The DNA damage repair ability was estimated by the kinetic curve of γH2AX foci, and the DNA-dependent protein kinase (DNA-PK) activation was detected by immunostaining assay.@*Results@#Primary cilia were frequently preserved in GBM, and the induction of ciliogenesis decreased cell proliferation. TMZ and IR promoted ciliogenesis in dose- and time-dependent manners, and the suppression of ciliogenesis significantly enhanced the cellular sensitivity to TMZ and IR. The inhibition of ciliogenesis elevated the lethal effects of TMZ and IR via the impairment of autophagy and DNA damage repair. The interference of ciliogenesis reduced DNA-PK activation, and the knockdown of DNA-PK led to cilium formation and elongation.@*Conclusion@#Primary cilia play a vital role in regulating the cellular sensitivity to TMZ and IR in GBM cells through mediating autophagy and DNA damage repair.

Investigate the thyroid function of radiation workers and analysis of influence factors / 中华劳动卫生职业病杂志

Objective: To analyze the thyroid condition and influencing factors of radiation workers, and to provide scientific basis for radiation protection management. Methods: In April 2020, 4308 radiation workers from October 1, 2017 to September 30, 2019 were collected for occupational health examination in Hangzhou Occupational Disease Prevention and Treatment Hospital, the data included basic information, Thyroid hormone level and thyroid color doppler ultrasound results. The thyroid status of radiation workers in different subgroups was compared. The influencing factors of Thyroid nodule were analyzed by multiple logistic regression. Results: 616 radiation workers had abnormal thyroid gland (14.3%, 616/4308) . The main manifestations of thyroid gland abnormality were abnormal Thyroid nodule (5.1%, 220/4308) and abnormal TSH level (7.1%, 308/4308) . Compared with the male radiation workers, the abnormal rate of Thyroid nodule, T3 and Tsh in female radiation workers was higher (P<0.05) , and the abnormal rate of Thyroid nodule, T3 and T4 increased with the increase of working age (P<0.05) . Radiation Workers in non-rated medical institutions and private medical institutions had the highest detection rate of Thyroid nodule (P<0.05) , and there was no significant difference in thyroid abnormalities among Workers (P<0.05) . By multiple logistic regression analysis, Sex (female) , age and institution type (private) were all independent risk factors for Thyroid nodule (95% CI: 1.548~2.763、1.002~1.030, P<0.05) . Conclusion: Ionizing radiation can cause thyroid damage in radiation workers, so we should pay more attention to the radiation protection management of female, high age, private and district medical organizations, so as to protect the health of radiation workers.

Estudo de coorte sobre exposição ocupacional à radiação ionizante e câncer em instituição pública brasileira / Cohort study on occupational exposure to ionizing radiation and cancer in a Brazilian public institution

Introdução - O câncer é doença crônica não transmissível multifatorial e no rol dos seus fatores de risco estão aqueles relacionados ao trabalho. A radiação ionizante é considerada carcinogênica e está presente em alguns ambientes de trabalho. Vários estudos foram feitos no mundo no intuito de estudar a relação sobre a mortalidade e a incidência por câncer em trabalhadores com risco de exposição ocupacional à radiação ionizante. Objetivo - Este estudo visa estimar as taxas de mortalidade e de incidência por câncer em uma unidade de trabalho com radiação ionizante sediada no município de São Paulo e identificar a associação potencial entre câncer e exposição à radiação ionizante no ambiente de trabalho. Métodos - Foi feito estudo de coorte retrospectiva aberta com trabalhadores que tiveram vínculo empregatício desde 31/08/1956 até 31/12/2016 a partir de dados coletados na empresa e em registros oficiais de óbitos e casos novos. Foram calculadas as razões de mortalidade padronizadas (RMP) e as razões de incidência padronizadas (RIP) por sexo de cânceres agrupados segundo o tipo (sólido, indeterminado e hematopoiético), o fator de risco (etilismo, tabagismo, ocupacional e radiação gama e X) e o sistema orgânico (tratos digestório, respiratório, ossos e tecidos moles, pele, geniturinário, olhos e sistema nervoso central, endócrino, indeterminado e hematopoiético) na análise externa comparando a população de estudo com a população geral do município de São Paulo e na análise interna, comparando o subgrupo monitorado para radiação gama e X com o subgrupo não monitorado. Foram feitas análises de regressão de Poisson univariada e múltipla dos fatores associados à incidência de câncer. Resultados - Foi encontrado o efeito do trabalhador sadio na análise externa de mortalidade (RMP = 0,224 IC95%: 0,208; 0,240) e interna de mortalidade (RMP = 0,685 IC95%: 0,618; 0,758). Na análise externa de incidência houve associação com os cânceres de pele (RIP = 19,703 IC95%: 7,303; 43,533) (p<0,001) e na análise interna de incidência houve associação com os cânceres hematopoiéticos (RIP = 1,593 IC95% 1,03; 2,351) (p<0,026), osteomusculares (RIP = 4,559 IC95% 1,821; 9,366) (p<0,001), de pele (RIP = 2,58 IC95%1,538; 2,748) (p<0,001) e de tireoide (RIP = 2,346 IC95% 1,452; 3,587) (p<0,001). Houve aumento da incidência de câncer entre as mulheres, os trabalhadores de nível socioeconômico elevado, entre aqueles que trabalharam por mais de cinco anos na empresa, entre aqueles que encerraram o acompanhamento na coorte até 49 anos de idade e entre aqueles que tiveram dose acumulada igual ou maior do que 20 mSv. Conclusão - este trabalho apresentou resultados semelhantes ao de outros estudos e ratificou os parâmetros de proteção radiológica.

Introduction - Cancer is a multifactorial non-communicable chronic disease and its risk factors include those related to work. Ionizing radiation is considered carcinogenic and is present in some work environments. Several studies have been carried out around the world in order to study the relationship between cancer incidence and mortality in workers at risk of occupational exposure to ionizing radiation. Objective - This study aims to estimate cancer incidence and mortality rates in a work unit with ionizing radiation based in the city of São Paulo and to identify the potential association between cancer and exposure to ionizing radiation in the work environment. Methods - A retrospective open cohort study was carried out with workers who had an employment relationship from 08/31/1956 to 12/31/2016 based on data collected in the company and in official records of deaths and new cases of cancer. Standardized mortality ratios (SMR) and standardized incidence ratios (SIR) were calculated for sex of cancers grouped according to type (solid, indeterminate and hematopoietic), risk factor (alcoholism, smoking, occupational and gamma and X radiation) and the organic system (digestive, respiratory tracts, bones and soft tissues, skin, genitourinary tract, eyes and central nervous system, endocrine, indeterminate and hematopoietic system) in the external analysis comparing the study population with the general population of the city of São Paulo and in the internal analysis, comparing the monitored subgroup for gamma and X radiation with the unmonitored subgroup. Univariate and multiple Poisson regression analyzes of factors associated with cancer incidence were performed. Results - The healthy worker effect was found in the external analysis of mortality (SMR = 0.224 95%CI: 0.208; 0.240) and internal (SMR = 0.685 95% CI: 0.618; 0.758). In the external analysis of incidence there was an association with skin cancers (SIR = 19.703 CI95%: 7.303; 43.533) (p<0.001) and in the internal analysis of incidence there was an association with hematopoietic cancers (SIR = 1.593 CI95% 1.03; 2.351) (p<0.026), musculoskeletal (SIR = 4.559 95% CI 1.821; 9.366) (p<0.001), skin (SIR = 2.58 95%CI1.538; 2.748) (p<0.001), and thyroid (SIR = 2.346 95%CI 1.452; 3.587) (p<0.001). There was an increase in the incidence of cancer among women, workers of high socioeconomic status, among those who worked for more than five years at the company, among those who ended follow-up in the cohort up to 49 years of age and among those who had an equal accumulated dose or greater than 20 mSv. Conclusion - this study presented results similar to those of other studies and ratified the parameters of radiological protection.

Ultrasonido endoscópico (USE) y colangio-pancreatografía endoscópica retrógrada (CPRE) sin fluoroscopia en el tratamiento de la coledocolitiasis durante el embarazo: reporte de 2 casos / Endoscopic ultrasound (EUS) and endoscopic retrograde cholangiopancreatography (ERCP) without fluoroscopy for the treatment of choledocholithiasis during pregnancy: Report of 2 cases

Resumen La enfermedad litiásica biliar es una patología frecuente en mujeres embarazadas, y las complicaciones relacionadas con los cálculos biliares durante el embarazo pueden generar desenlaces adversos tanto en la madre como en el feto. La coledocolitiasis en el embarazo requiere de una aproximación diagnóstica adecuada y su manejo busca minimizar los riesgos de las intervenciones médicas. Se describen dos casos de mujeres embarazadas quienes presentan coledocolitiasis documentada por colangiorresonancia. Se realizó el tratamiento con la combinación de ultrasonido endoscópico (USE) y colangiopancreatografía endoscópica retrógrada (CPRE) sin fluoroscopia, con lo cual se logró resolver la coledocolitiasis sin exponer al feto a radiación ionizante, se confirmó la permeabilización del colédoco y se observó una adecuada evolución posoperatoria tanto materna como fetal.

Abstract Biliary lithiasis is a common condition in pregnant women, and complications related to gallstones during pregnancy can lead to adverse outcomes in both the mother and the fetus. Choledocholithiasis during pregnancy requires an adequate diagnostic approach to minimize the risks of medical interventions. The following are two cases of pregnant women with choledocholithiasis diagnosed using magnetic resonance cholangiography. Treatment included a combination of endoscopic ultrasound and retrograde endoscopic cholangiopancreatography (ERCP) without fluoroscopy, achieving the resolution of choledocholithiasis, without exposing the fetus to ionizing radiation, confirming the permeabilization of the common bile duct, and observing an adequate postoperative evolution of both the mother and the fetus.

X-radiation does not affect the dental pulp: a morphological study in rats / A radiação X não afeta a polpa dentária: um estudo morfológico em ratos

Introduction: Radiotherapy is one of the methods used as a treatment for malignant tumors in the head and neck region and it can cause tissue damage in the irradiated areas. In head and neck radiotherapy, teeth are often included within the irradiation area and, consequently, the dental pulp; which receives high doses of radiation. Objective: To evaluate the effects of ionizing radiation on the pulp tissue of rat teeth. Methodology: A double-blind experimental assay with 35 Albinus Wistar rats divided into seven groups was performed; one control group, three groups irradiated with 15 Gy, and three groups irradiated with 25 Gy. The irradiated groups were submit-ted to a single dose of radiation and sacrificed 24 hours, 7 days, and 22 days after irradiation, respectively. The samples were evaluated for the morphological presence of inflammatory infiltrate, edema, necrosis, fibrosis, and degeneration of blood vessels. Statistical analysis was performed using the Kruskal-Wallis and Dunn tests with p < 0.05. Results: Hyaline degeneration of the pulp blood vessels in the irradiated teeth was statistically signifi-cant in all irradiated groups. Inflammatory infiltrate, edema, necrosis or fibrosis was not observed. Conclusion:A single X-radiation dose is not able to affect the dental pulp connective tissue in the long term with no clinical damage.

Introdução: A radioterapia é um dos métodos utilizados como tratamento para tumores malignos em região de cabeça e pescoço e que pode causar danos aos tecidos nas áreas irradiadas. Na radioterapia de cabeça e pescoço, os dentes são comumente incluídos dentro da área de radiação e, consequentemente, a polpa dentária, recebe altas doses de radiação. Objetivo: Avaliar os efeitos da radiação ionizante no tecido pulpar de dentes de ratos. Metodologia: Foi realizado um ensaio experimental duplo-cego com 35 ratos Albinus Wistar divididos em sete grupos: um grupo controle, três grupos irradiados com 15 Gy e três grupos irradiados com 25 Gy. Os grupos irradiados foram submetidos a uma dose única de radiação e sacrificados 24 horas, 7 dias e 22 dias após a irradiação, respectivamente. As amostras foram avaliadas quanto à presença morfológica de infiltrado inflamatório, edema, necrose, fibrose e degeneração nos vasos sanguíneos. A análise estatística foi realizada por meio dos testes de Kruskal-Wallis e Dunn com p < 0.05. Resultados: Degeneração hialina nos vasos sanguíneos pulpares dos dentes irradiados foi estatisticamente significante em todos os grupos irradiados. Não foi observado infiltrado inflamatório, edema, necrose ou fibrose. Conclusão: Uma dose única de radiação X não é capaz de afetar o tecido conjuntivo da polpa dentária a longo prazo sem danos clínicos.

Caracterización de estudios por imágenes realizados en niños sanos en un centro de atención ambulatoria: percepciones, creencias y expectativas de sus padres / Characterizing imaging studies in healthy pediatric patients in an ambulatory center: parental perceptions, beliefs and expectations

Introducción: los estudios por imágenes (EPI) son de gran ayuda para el diagnóstico clínico, pero su uso irracional puede ocasionar daños. Objetivos: relevar las percepciones y expectativas sobre estudios por imágenes pediátricos en un grupo de padres de niños sanos. Evaluar los datos obtenidos en relación con el registro de EPI solicitados por Guardia durante el mismo período. Materiales y métodos: estudio exploratorio, descriptivo, cuali-cuantitativo mediante una encuesta en una muestra por conveniencia en un centro pediátrico ambulatorio, a lo largo de dos meses. Análisis retrospectivo de solicitud de EPI en el registro informatizado de historias clínicas de Guardia durante el mismo período. Resultados: respondieron 243 padres. El 93,4% refirió conocer métodos de EPI (la radiografía[Rx] fue el más conocido). Se había realizado al menos un EPI al 83,4% de los niños en los últimos doce meses. El estudio fue explicado en forma clara en el 96,4% de los casos. Un 47,7% de los padres refirieron conocer las consecuencias del uso repetitivo de EPI. El 81,6% acordó con que "ante cualquier traumatismo se debe realizar Rx para descartar fractura". Más del 60% consideró que debe realizarse Rx de tórax a todo niño con tos sin fiebre o con fiebre de más de dos días y 55% solicitarían Rx de senos paranasales si el niño elimina mocos verdes. El 49,8% opinó que los médicos piden EPI de menos (por falta de recursos, para trabajar menos o para ahorrar dinero). Durante el período estudiado se solicitó una radiografía al 5% de los pacientes que consultaron por Guardia; no se encontró justificación para solicitar el estudio en el 29% de los casos. Conclusión: un gran porcentaje de padres conoce los EPI; sin embargo, desconocen los riesgos asociados a su uso. Existen errores de concepto que generan expectativas desmedidas con respecto a la indicación de Rx. Se informó un exceso en las solicitudes de EPI por Guardia. Los padres consideran que los médicos solicitan EPI de menos. (AU)

Introduction: ediatric radiologic exams (PRE) are of great value for clinicians. It's over or misuse can lead to irreparable damage that can be prevented. Objective: to describe perceptions and expectations for the use of PRE among healthy children`s parents in an ambulatory center. To analyze these results in relation to the report of PRE performed in the emergency room during the same period. Methods: observational, cross sectional, quali- quantitative study using a survey on a convenience sample conducted in an outpatient pediatric center over a two months period. Retrospective analysis of medical records to evaluate PRE requested on the ER during the 2 months of the study. Results: 243 parents completed the survey. 93,4% were familiar with PRE (X-rays being the most popular among them). 83,4% of children in our sample had at least one PRE in the past 12 months. The need and utility of the study had been explained to the parents clearly in 96,4% of cases. 47,7% of parents knew about the side effects associated with repetitive use of PRE. 81,6% agreed with the statement "in the event that a child should suffer any trauma, an X-Ray should be performed to look for fractures". Over 60% think a chest X ray has to be obtained if the child has fever for over 48 hours and 55% would expect an X ray to be performed whenever a child has green nasal discharge. 49,8% respondents think that doctors order less than necessary (for lack of resources, unwillingness to work in or to save money). The analysis of clinical reports showed that X-Rays were performed to 5% of children at the emergency clinic. Among them, we found no reason for the study in 29% of the cases. Conclusion: we found that parents were very familiar with PRE, however less than half our sample knew of the potential risks related to their use. There are considerable misconceptions among parents regarding X-Ray use. Parents considered that doctors order too little PRE. (AU)

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)

Effects of exposure to low-dose ionizing radiation on changing platelets: a prospective cohort study

BACKGROUND@#Numerous studies have concentrated on high-dose radiation exposed accidentally or through therapy, and few involve low-dose occupational exposure, to investigate the correlation between low-dose ionizing radiation and changing hematological parameters among medical workers.@*METHODS@#Using a prospective cohort study design, we collected health examination reports and personal dose monitoring data from medical workers and used Poisson regression and restricted cubic spline models to assess the correlation between changing hematological parameters and cumulative radiation dose and determine the dose-response relationship.@*RESULTS@#We observed that changing platelet of 1265 medical workers followed up was statistically different among the cumulative dose groups (P = 0.010). Although the linear trend tested was not statistically significant (P@*CONCLUSION@#We concluded that although the exposure dose was below the limit, medical workers exposed to low-dose ionizing radiation for a short period of time might have increased first and then decreased platelets, and there was a dose-response relationship between the cumulative radiation dose and platelets changing.