Irradiation injuries anti-agents refer to drugs that can inhibit the initial stage of radiation injuries, or reduce the development of radiation injuries and promote the recovery of injuries when used early after irradiation exposure. According to the mechanism of action and the time of intervention, the irradiation injuries anti-agents are divided into four categories: radioprotectors, radiomitigators, radiation therapeutics for external radiation exposure, and anti-agents for internalized radionuclides. In this paper, the research progress of irradiation injuries anti-agents in recent years is reviewed.
Humans ; Radiation-Protective Agents/therapeutic use* ; Radiation Injuries/prevention & control*

Central Nervous System ; radiation effects ; Eye ; radiation effects ; Humans ; Immune System ; radiation effects ; Radiation ; Radiation Injuries ; prevention & control ; Radiation Protection ; methods ; Reproduction ; radiation effects

Humans ; Radiation Injuries ; drug therapy ; prevention & control ; Radiation, Nonionizing ; Radiation-Protective Agents ; therapeutic use ; Radioactive Hazard Release ; prevention & control

Radiation proctitis denotes the radiation damage of rectum caused by radiotherapy to pelvic malignancy. The clinical practices of radiation proctitis should be fully considered from diagnosis, treatment and prevention. In order to determine appropriate treatment strategies, the diagnosis of radiation proctitis should be based on clinical symptoms, endoscopic findings, imaging and histopathology to assess severity of symptoms and stage of disease. In terms of treatment decisions, non-surgical interventions are generally applied to relieve major symptoms and avoid serious complications. Diverting colostomy and restorative resection are the main surgical treatments for patients with recurrent symptoms. In terms of prevention, radiation proctitis should be prevented by improvement of radiotherapy technology, physical protection and prophylactic medication. This guide aims to provide guidance for the clinical practices of radiation proctitis in China.
China ; Consensus ; Humans ; Proctitis ; diagnosis ; therapy ; Radiation Injuries ; diagnosis ; prevention & control ; therapy ; Rectum ; pathology ; radiation effects

International Commission on Radiological Protection (ICRP), an independent international organization established in 1925, develops, maintains, and elaborates radiological protection standards, legislation, and guidelines. United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR) provides scientific evidence. World Health Organization (WHO) and International Atomic Energy Agency (IAEA) utilise the ICRP recommendations to implement radiation protection in practice. Finally, radiation protection agencies in each country adopt the policies, and adapt them to each situation. In Korea, Nuclear Safety and Security Commission is the governmental body for nuclear safety regulation and Korea Institute of Nuclear Safety is a public organization for technical support and R&D in nuclear safety and radiation protection.
History, 20th Century ; Humans ; International Agencies/*organization & administration ; Radiation Injuries/etiology/prevention & control ; Radiation Protection/history/*legislation & jurisprudence ; Radiation, Ionizing

Animals ; Humans ; Hyperbaric Oxygenation ; Mandibular Diseases ; prevention & control ; therapy ; Osteoradionecrosis ; prevention & control ; therapy ; Radiation Injuries ; prevention & control ; therapy

OBJECTIVE: To observe histopathologic changes of irradiated guinea pigs' nasal mucosa treated with intranasal corticosteroids and to study the radioprotective effect of intranasal corticosteroids. METHOD: Fifty health guinea pigs nasal parts were performed irradiation by the WDVE-6MeV linear accelerator. They had accepted 5 Gy one time per week for three weeks through X-ray irradiating to establish the animal irradiation injury model. After that, they were divided into 2 groups randomly: the control group and the administration group and each group had 25 guinea pigs. The administration group received intranasal corticosteroids on the second day after three weeks irradiation, 5 animals per one group were sacrificed randomly at 1 W, 1 M, 2 M, 3 M, 4 M after administration, the histopathologic changes were observed under optical, scanning electron and transmission electron microscope respectively. RESULT: Using intranasal corticosteroids after irradiation, the early inflammatory reaction of the administration group was milder than the control group. With the drug being given constantly, the recovery of epithelial cell with irradiated damage was accelerated and the coverage rate of cilia went up obviously; After four months, the coverage rate of cilia had risen to 72.9%; But, for the control group, the coverage rate of cilia is only 50.2%. The atrophy of submucosal glandular organ was lessened and they displayed some extent secretory function. The reparation was accelerated as time went by. CONCLUSION Irradiation brought about serious injury on guinea pigs' nasal mucosa. But, the injury was lessen after using intranasal corticosteroids. Intranasal corticosteroids play the role of radioprotection for the irradiated nasal mucosa.
Adrenal Cortex Hormones ; pharmacology ; Animals ; Guinea Pigs ; Nasal Mucosa ; drug effects ; pathology ; radiation effects ; Radiation Injuries, Experimental ; prevention & control

OBJECTIVETo investigate the effect of Inonotus obliquus polysaccharides on testicular injury induced by exposure to high power microwave (HPM) in rats.

METHODSA total of 30 male Wistar rats were randomly divided into 5 groups, i.e., the normal control group, the microwave radiation model group, the treatment group, the new microwave radiation model group, and the prevention group, 6 in each group. All rats, except those in the normal control group, were exposed to microwave at an average power density of 200 mW/cm2 for 6 min. Rats in the control group and the model group were administered with normal saline by gastrogavage, once a day. Rats in the treatment group and the prevention group were given with Inonotus obliquus polysaccharides by gastrogavage, 2 mL each time (400 mg/kg body weight), once a day. All rats were sacrificed on the 11th day.The sperm density and the rate of sperm deformity were determined. Pathological changes of testis were observed by light microscope and transmission electron microscope.

RESULTSShort-term HPM irradiation could significantly reduce the sperm density and increase the sperm deformity rate (P < 0.05). Meanwhile, obvious pathological changes of testes occurred. Compared with the two model groups, the sperm density increased and the sperm deformity rate decreased in the treatment group and the prevention group (P < 0.05). Under the light microscope, injuries of spermatogenic cells and stromal cells, as well as vascular dilatation and congestion were obviously alleviated in the treatment group and the prevention group. Mitochondrial swelling and endoplasmic reticulum expansion shown by ultrastructural observation were also significantly alleviated. Of them, injuries of spermatogenic cells and inflammation response were milder in the treatment group than in the prevention group.

CONCLUSIONSInonotus obliquus polysaccharides had significant protective effect on microwave radiation induced testicular injury. Better effect was obtained by therapeutic medication than preventive medication.

Animals ; Basidiomycota ; chemistry ; Male ; Microwaves ; adverse effects ; Polysaccharides ; pharmacology ; Radiation Injuries, Experimental ; prevention & control ; Radiation-Protective Agents ; pharmacology ; Rats ; Rats, Wistar ; Testis ; drug effects ; pathology ; radiation effects

OBJECTIVETo study the impact of different planning target volume (PTV) margin settings on surface and superficial dose distribution and explore the resolution of high superficial dose when the target area is close to the surface during head and neck intensity-modulated radiotherapy (IMRT).

METHODSA typical superficial target volume was designed in an circular neck phantom. Two experimental inverse IMRT plans were conducted with 8MV X ray, and in plan A, the superficial side of PTV margin ranged from 0 to 5 mm, while other side margins were 5 mm; in plan B, an suppositional machine dosimetry data for IMRT optimization was established in which the build-up dose was eliminated, and this machine data was used to optimize the inverse IMRT plan followed by recalculation of the planned dose distribution with the actual clinical machine dosimetry data. The variation of the surface and superficial dose resulting from set-up error and the dose distribution to CTV were compared. The adequate PTV margin was analyzed when the CTV approached the surface.

RESULTSIn plan A, the high dose greater than the prescribed dose was found in the surface and superficial region when the superficial sparing distance was between the surface and PTV d<3 mm, and the 3 mm set-up margin increased this superficial dose remarkably. Reducing the superficial side of PTV margin lowered the high superficial dose effectively and allowed maintenance of the prescribed dose to the CTV. To avoid reduction of the dose to the CTV to below 95% of the prescribed dose, the superficial side of PTV margin should be greater than 1 mm. Plan B effectively lowered the surface doses and maintained the prescribed dose to the CTV.

CONCLUSIONSWith appropriate techniques for optimizing inverse IMRT, more homogeneous superficial dose can be achieved.

Computer Simulation ; Head and Neck Neoplasms ; radiotherapy ; Humans ; Radiation Injuries ; prevention & control ; Radiation Protection ; methods ; Radiotherapy Planning, Computer-Assisted ; methods ; Radiotherapy, Intensity-Modulated ; methods ; standards ; Skin ; radiation effects

OBJECTIVETo determine the repair half-time (T1/2), a speed parameter of sub-lethal damage repair (SLDR), of human nasopharyngeal carcinoma (NPC) cell lines CNE1, HONE1, C666-1 and CNE2.

METHODSA total radiation dose of 8 Gy divided into 4+4 Gy was delivered to the cell lines at the interval of 0 s, 15 s, 30 s, 1 h, 2 h, 4 h or 6 h. The cell survival fractions were determined using the standard cell clonogenic assay. The curves of the changes in the surviving cell fraction after a total dose of 8 Gy, as a function of the interval between the two doses of 4 Gy, were fitted manually, and the T1/2 of each cell line was calculated according to the curves.

RESULTSThe T1/2 of CNE1, HONE1, C666-1 and CNE2 were 18 s, 22 s, 29 s and 27 s, respectively.

CONCLUSIONThe speed of SLDR of NPC cells is quite rapid, indicating that the fraction delivery time longer than 20 s might decrease the effect of radiotherapy.

Cell Line, Tumor ; Cell Survival ; radiation effects ; Dose-Response Relationship, Radiation ; Humans ; Nasopharyngeal Neoplasms ; pathology ; radiotherapy ; Radiation Injuries ; prevention & control ; Radiotherapy, Conformal ; Radiotherapy, Intensity-Modulated