贫铀对小鼠睾丸生精细胞和精子遗传损伤的初步研究

目的　初步探讨小鼠吸入不同剂量的贫铀 (DU)气溶胶对生精细胞和精子的遗传损伤作用。方法　采用小鼠睾丸初级精母细胞染色体畸变试验、小鼠睾丸生殖细胞微核试验和精子染色质结构试验 (SCSA) ,评价DU诱导小鼠生精细胞和精子的遗传损伤程度。结果　吸入DU气溶胶组睾丸生殖细胞微核发生率与对照组相比无显著差异 ,吸入 ( 73 1 5 2± 3 5 99)和 ( 877 83± 43 19)ng gDU组小鼠睾丸初级精母细胞染色体数目畸变率为 17 2 %和 2 7 2 %,与对照组比较显著升高 (P <0 0 1) ;精子染色质结构试验中 ,对照组、吸入 ( 73 1 5 2± 3 5 99)和 ( 877 83± 43 19)ng gDU组的精子SCSA各变量平均值 :αT分别为 2 5 3 5 1± 3 1 76、2 88 2 9± 68 3 0、2 94 5 6± 72 90 ,%COMP分别为 3 73± 5 5 0、9 0 2± 4 43、9 11± 5 3 3 ,%GREEN分别为 0 89± 0 44、1 62± 1 0 6、1 80± 0 61,DU组各变量值与对照组比较均有显著增高 (P <0 0 5 )。结论　小鼠吸入贫铀气溶胶可诱导生精细胞和精子遗传损伤     

Autofluorescence (safe) bronchoscopy and p21/ki-67 immunostaining related to carcinogenesis

Archival biopsy materials from 20 randomly selected asymptomatic volunteers from the Czech uranium miners (CZ UM) risk group (n=98) were examined for p21 and ki-67 immunostatning. There were 16 areas with normal respiratory epithelium and 22 areas with bronchial intra-epithelial neoplasia (IEN). Normal and IEN areas were identified by autofluorescence (System Autofluorescence Endoscopy, SAFE-1000) and monitored during 1998–2002. The majority of specimens from areas with normal autofluorescence intensity with ciliated columnar bronchial epithelium showed strong predominantly cytoplasmic p21 positivity. The SAFE monitoring divided areas of decreased autofluorescence intensity with early stage IEN lesions into two groups. Persistent lesions (P)—showing a spectrum of p21 cytoplasmic staining ranging from negative or isolated negativity to weak or moderate positivity combined with higher proliferative capacity proved by ki-67 nuclear staining. Disappearing lesions (D)—showing strong cytoplasmic p21 positivity and negative ki-67 staining. The IEN lesions were classified into three groups based on p21/ki-67 immunostaining: proliferative lesions at risk (R) with low or without p21 plasma immunostaining combined with high ki-67 nuclear reactivity; ambiguous lesions (A) including cases combining strong p21 cytoplasmic positivity with high ki-67 nuclear reactivity or p21 cytoplasmic negativity with ki-67 negativity staining patterns; the quiescent lesion group (Q) was characterized by strong p21 cytoplasmic positivity and negative ki-67 immunostaining.     

铀矿地质放射作业人员健康状况观察

目的　探讨低剂量长期职业辐射对作业人员健康状况的影响。方法　选择 176名长期从事铀矿地质勘探放射作业人员为作业组 ,另选 38名非放射性作业人员为对照组 ,进行了血常规、免疫球蛋白、T淋巴细胞亚群、外周血淋巴细胞微核以及血清皮质醇 (CS)、三碘甲状腺原氨酸 (T3 )、甲状腺素 (T4)的测定。结果　作业组人员的血常规、免疫功能指标水平以及外周血淋巴细胞微核率变化与对照组相近 ,差异无显著性 ;内分泌指标中作业组的CS水平显著低于对照组 (P <0 0 1) ,而作业组的T3 水平显著高于对照组 (P<0 0 1) ,T4水平两组间差异无显著性。结论　长期接触小剂量、低剂量率职业受照射人员除内分泌指标有所变化外 ,其血常规、免疫学指标、遗传学指标的淋巴细胞微核均未见特殊变化     

铀促排药物研究VⅢ:邻苯二酚类鳌合剂的新法合成

In further study on the synthesis of chelating agents with catechol residue,twoconvenient procedures-ethyl chloroformate method and dicyclohexylcarbodiimide(DCC)method-weredeveloped.The latter was used successfully to synthesize chelating agents with several catechol units.These compounds are more effective than compounds with only one catechol unit to detoxicate micewhich were under acute UO₂(NO₃)₂ intoxication(LD_95～100).     

Role of the olfactory receptor neurons in the direct transport of inhaled uranium to the rat brain

Uranium presents numerous industrial and military uses and one of the most important risks of contamination is dust inhalation. In contrast to the other modes of contamination, the inhaled uranium has been proposed to enter the brain not only by the common route of all modes of exposure, the blood pathway, but also by a specific inhalation exposure route, the olfactory pathway. To test whether the inhaled uranium enter the brain directly from the nasal cavity, male Sprague–Dawley rats were exposed to both inhaled and intraperitoneally injected uranium using the ²³⁶U and ²³³U, respectively, as tracers. The results showed a specific frontal brain accumulation of the inhaled uranium which is not observed with the injected uranium. Furthermore, the inhaled uranium is higher than the injected uranium in the olfactory bulbs (OB) and tubercles, in the frontal cortex and in the hypothalamus. In contrast, the other cerebral areas (cortex, hippocampus, cerebellum and brain residue) did not show any preferential accumulation of inhaled or injected uranium. These results mean that inhaled uranium enters the brain via a direct transfer from the nasal turbinates to the OB in addition to the systemic pathway. The uranium transfer from the nasal turbinates to the OB is lower in animals showing a reduced level of olfactory receptor neurons (ORN) induced by an olfactory epithelium lesion prior to the uranium inhalation exposure. These results give prominence to a role of the ORN in the direct transfer of the uranium from the nasal cavity to the brain.     

铀矿矽肺动态分析

目的了解铀矿工矽肺发病情况规律与特点，综合评价铀矿工矽肺防治效果。方法对３个铀矿和两个铀矿地质勘探队进行流行病学调查研究。结果所有矽肺病例开始接尘时间均在五六十年代。自建矿、建队以来的３０多年中，粉尘浓度、矽肺检出率呈下降趋势，矽肺发病工龄、发病年龄、晋期年限、病程与死亡年龄均呈延长趋势。晚发矽肺比例为２０．３１％。只有铀矿粉尘接尘史的矽肺病例平均发病工龄７．４７年，平均发病年龄３６．７４岁，短于有其他非铀矿粉尘接尘史的混合接尘矽肺病例。结论铀矿工矽肺综合防治效果显著。只有铀矿粉尘接尘史的矽肺病例平均发病工龄短，平均发病年龄较轻     

铀矿矽肺预后分析

为了解铀矿工矽肺生存情况的规律与特点,对铀矿工矽肺预后进行预测。利用单因素方法,结合寿命表法、Ｋａｐｌａｎ－Ｍｅｉｅｒ法及分层Ｃｏｘ回归法对部分铀矿和铀矿地质勘探队的铀矿矽肺病例预后进行综合分析研究。结果为铀矿和铀矿地质勘探队的铀矿矽肺病例的病死率差别有高度性,影响铀矿矽肺病例预后的主要因素为铀矿接尘工龄、工种、是否并发肺结核及初次诊断为矽肺病的期次。利用生存概率与预后指数关系曲线可对铀矿矽肺病例     

The first use of U in the general environment and near a shutdown nuclear power plant

We present a first effort to investigate ²³⁶U in the environment near a shutdown nuclear power plant far away from highly contaminated sites, by using accelerator mass spectrometry. The detection limit of about 1 pg ²³⁶U allowed us to identify a minimal increase of the ²³⁶U/²³⁸U isotopic ratio correlated to a peak of ¹³⁷Cs in river sediments downstream of the nuclear power plant, and to detect anthropogenic ²³⁶U also upstream, where it is probably not related to the power plant but to global fallout. The ²³⁶U content shoved variations of the ²³⁶U/²³⁸U isotopic ratio in relation to the chemical–physical characteristics of the sediments. This demonstrates the potential of ²³⁶U as an environmental tracer, and as an indicator for releases from nuclear facilities.     

典型地区茶叶中天然铀和钍含量分布

目的 掌握我国典型地区茶叶中天然铀钍的含量及其分布水平,建立微波消解-高分辨质谱分析茶叶样品中铀、钍的方法。方法 以15个省的20种茶叶为样本,通过微波消解-电感耦合等离子体质谱分析茶叶中铀、钍的含量。结果 铀、钍的检出限分别为11、8.0 ng/L,铀、钍的回收率分别介于97.5%~102.0%和96.9%~102.3%。20种茶叶样品铀、钍含量均低于国家标准规定的铀、钍限值1.5和0.96 mg/kg,样品中钍含量普遍高于铀。结论 茶叶中铀、钍含量有一定的区域性分布差异,西部地区、中南地区的茶叶铀钍含量略高于华东、华南地区。     

铀促排药物研究Ⅱ:邻苯二酚类胺羧酰胺螯合剂的合成

铀化合物不但有化学毒性,会引起肾炎、蛋白尿等,还有放射性毒害作用,因此,如何有效地防护铀中毒和解毒是一个重要课题。前文报道了几种膦酸类螯合剂的合成及其排铀效果。钛铁试剂(Ⅰ)有较好的排铀能力,主要是由于邻苯二酚基团和UO_2~(2+)的螯合作用。enterobactin和Fe~(3+)的螯合稳定常数达10~(52),其类似物LICAM(Ⅱ)不仅和Fe~(3+),而且和Pu~(4+)的螯合能力极好,估计也会和UO_2~(2+)生成稳定的螯合物。这类化合物除有邻苯二酚结构外,都还含有多个酰胺基团。