高山开采铀矿山安全防护研究

某铀矿山位于海拔3000 m以上,属于高山采矿,由于高山采矿不但存在地质灾害频发、工业场地安全性较差的问题,更重要的是高山铀矿山开采过程中还有具有高山病和放射性危害。在矿山设计中,应充分考虑高原采矿的特殊性,采取有针对性的安全措施,降低矿山开采中风险,使井下生产能够安全、顺利的进行。     

建筑材料中放射性核素限量标准的探讨

《建筑材料放射性核素限量》（GB6566—2001）结束了我国建材标准长期不统一的局面，规定了对建材中放射性实现强制检定的要求，但在装修材料分类、空心材料、废渣利用、测量方法等方面存在着一些不合理的规定。与以往的国家标准相比。对建材中的放射性控制明显放宽，甚至比原来的建材行业标准对石材的控制还要宽，影响了公众的辐射防护安全。对此进行了详细的分析和讨论。     

利用计算机逻辑实现60Co货运列车检查系统列车辐射安全控制

介绍了^60Co货运列车检查系统的列车辐射安全设计。控制系统通过失效保护、冗余设计、可靠的连锁逻辑、应急措施等,来保证入境待检货车司机、入境客车以及出境列车的辐射安全。     

Human Anti-Oxidation Protein A1M—A Potential Kidney Protection Agent in Peptide Receptor Radionuclide Therapy

Peptide receptor radionuclide therapy (PRRT) has been in clinical use for 15 years to treat metastatic neuroendocrine tumors. PRRT is limited by reabsorption and retention of the administered radiolabeled somatostatin analogues in the proximal tubule. Consequently, it is essential to develop and employ methods to protect the kidneys during PRRT. Today, infusion of positively charged amino acids is the standard method of kidney protection. Other methods, such as administration of amifostine, are still under evaluation and show promising results. α₁-microglobulin (A1M) is a reductase and radical scavenging protein ubiquitously present in plasma and extravascular tissue. Human A1M has antioxidation properties and has been shown to prevent radiation-induced in vitro cell damage and protect non-irradiated surrounding cells. It has recently been shown in mice that exogenously infused A1M and the somatostatin analogue octreotide are co-localized in proximal tubules of the kidney after intravenous infusion. In this review we describe the current situation of kidney protection during PRRT, discuss the necessity and implications of more precise dosimetry and present A1M as a new, potential candidate for renal protection during PRRT and related targeted radionuclide therapies.     

整体式除氚催化剂的制备及催化氧化性能

针对大型核设施产生的大流量废气的处理,发展低气阻的整体式催化剂尤为必要。本工作在整体式堇青石载体上生长分子筛涂层,以离子交换法负载活性组分Pt,获得的整体式催化剂具有高的金属分散度,达到了60%。使用该催化剂,在15℃、体积空速为10 000～40 000 h^-1、1.0%(体积分数)H₂的条件下实现大于99.9%的H₂转化率;在25℃、体积空速为50 000 h^-1、1.0%H₂的条件下实现H₂的完全转化。在更低的H₂浓度下(0.1%H₂和0.5%H₂),该催化剂在湿条件下的H₂转化率低于干条件下的H₂转化率,表明水蒸气会抑制室温催化活性。由于分子筛涂层较Al₂O₃涂层具有更低的吸水性,整体式Pt/sil-cord催化剂在湿条件下具有比Pt/Al₂O₃高得多的...     

1983—1984年抗辐射药物研究概况

本文综述1983—1984年可以看到的有关辐射防护剂主要文献66篇。包括含硫化合物、杂环化合物、胺类、抗氧化剂、含羟基物质和糖、性激素、抗菌素和维生素、生物生化制剂、微生物制品和免疫调节药、多糖和其他天然药物、金属及其络合物等,并获得如下印象:(1)1983—1984年间国内外关于抗辐射药物的研究继续取得良好的进展,主要表现在对抗放作用机制的深入研究和抗放药物的临床应用(包括放疗及其他疾病)两方面。(2)关于新的辐射防护剂的探索,范围仍是十分广泛的,但仍待有重点、有选择地研究其中一些化合物或制剂应用于临床的可能性。     

Clinically Approved Carbon Nanoparticles with Oral Administration for Intestinal Radioprotection via Protecting the Small Intestinal Crypt Stem Cells and Maintaining the Balance of Intestinal Flora

The exploration of an old drug for new biomedical applications has an absolute predominance in shortening the clinical conversion time of drugs for clinical application. In this work, carbon nanoparticles suspension injection (CNSI), the first clinically approved carbon nanoparticles in China, is explored as a new nano‐radioprotective agent for potent intestinal radioprotection. CNSI shows powerful radioprotective performance in the intestine under oral administration, including efficient free radical scavenging ability, good biosafety, high chemical stability, and relatively long retention time. For example, CNSI shows high reactive oxygen species (ROS) scavenging activities, which effectively alleviates the mitochondrial dysfunction and DNA double‐strand breaks to protect the cells against radiation‐induced damage. Most importantly, this efficient ROS scavenging ability greatly helps restrain the apoptosis of the small intestinal epithelial and crypt stem cells, which decreases the damage of the mechanical barrier and thus relieves radiation enteritis. Moreover, CNSI helps remove the free radicals in the intestinal microenvironment and thus maintain the balance of intestinal flora so as to mitigate the radiation enteritis. The finding suggests a new application of clinically approved carbon nanoparticles, which not only promotes the development of new intestinal radioprotector, but also has a great potential for clinical transformation.     

Protective Effect of Anthocyanin from Lonicera Caerulea var. Edulis on Radiation-Induced Damage in Mice

The radioprotective effect of anthocyanin extracted from Lonicera caerulea var. edulis (ALC), was studied in ICR mice. Different doses of ALC were intragastrically administered to mice once a day, prior to radiation. After two weeks, the mice received a one-time 5 Gy whole body ⁶⁰Coγ radiation. The spleen index, thymus index, activities of superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px), malondialdehyde (MDA) content, and glutathione (GSH) content in liver tissue were measured. Compared with the radiation control group, the levels of MDA in all ALC treated groups decreased significantly (p < 0.05). Moreover, the GSH content, activities of SOD and GSH-Px in liver tissue were enhanced significantly (p < 0.05) in all ALC groups. These results demonstrate that ALC may be a potential radioprotector, and a further study of the molecular mechanism is needed for further application.     

The Flaxseed-Derived Lignan Phenolic Secoisolariciresinol Diglucoside (SDG) Protects Non-Malignant Lung Cells from Radiation Damage

Plant phenolic compounds are common dietary antioxidants that possess antioxidant and anti-inflammatory properties. Flaxseed (FS) has been reported to be radioprotective in murine models of oxidative lung damage. Flaxseed’s protective properties are attributed to its main biphenolic lignan, secoisolariciresinol diglucoside (SDG). SDG is a free radical scavenger, shown in cell free systems to protect DNA from radiation-induced damage. The objective of this study was to investigate the in vitro radioprotective efficacy of SDG in murine lung cells. Protection against irradiation (IR)-induced DNA double and single strand breaks was assessed by γ-H2AX labeling and alkaline comet assay, respectively. The role of SDG in modulating the levels of cytoprotective enzymes was evaluated by qPCR and confirmed by Western blotting. Additionally, effects of SDG on clonogenic survival of irradiated cells were evaluated. SDG protected cells from IR-induced death and ameliorated DNA damage by reducing mean comet tail length and percentage of γ-H2AX positive cells. Importantly, SDG significantly increased gene and protein levels of antioxidant HO-1, GSTM1 and NQO1. Our results identify the potent radioprotective properties of the synthetic biphenolic SDG, preventing DNA damage and enhancing the antioxidant capacity of normal lung cells; thus, rendering SDG a potential radioprotector against radiation exposure.     

Intestinal Radiation Protection and Mitigation by Second-Generation Probiotic Lactobacillus-reuteri Engineered to Deliver Interleukin-22

(1) Background: The systemic administration of therapeutic agents to the intestine including cytokines, such as Interleukin-22 (IL-22), is compromised by damage to the microvasculature 24 hrs after total body irradiation (TBI). At that time, there is significant death of intestinal microvascular endothelial cells and destruction of the lamina propria, which limits drug delivery through the circulation, thus reducing the capacity of therapeutics to stabilize the numbers of Lgr5+ intestinal crypt stem cells and their progeny, and improve survival. By its direct action on intestinal stem cells and their villus regeneration capacity, IL-22 is both an ionizing irradiation protector and mitigator. (2) Methods: To improve delivery of IL-22 to the irradiated intestine, we gavaged Lactobacillus-reuteri as a platform for the second-generation probiotic Lactobacillus-reuteri-Interleukin-22 (LR-IL-22). (3) Results: There was effective radiation mitigation by gavage of LR-IL-22 at 24 h after intestinal irradiation. Multiple biomarkers of radiation damage to the intestine, immune system and bone marrow were improved by LR-IL-22 compared to the gavage of control LR or intraperitoneal injection of IL-22 protein. (4) Conclusions: Oral administration of LR-IL-22 is an effective protector and mitigator of intestinal irradiation damage.