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1.
Wladimir Wertelecki 《Congenital anomalies》2021,61(1):9-13
We report population prevalence rates of neural tube defects (NDT) and microcephaly (MIC) as well as levels of incorporated Cs137 by pregnant women in two areas of the Rivne Province of Ukraine, a northern half (Polissia) polluted by Chornobyl radiation and not‐Polissia areas. Monitoring of congenital malformations was conducted with adherence to methods adopted by a European surveillance network (EUROCAT). Incorporated Cs137 (Bq/kg) by pregnant women residing in the Polissia and not‐Polissia areas were obtained concurrently with prenatal ultrasound examinations. In Polissia, the incorporated Cs137 levels by pregnant women as well as the prevalence rates of NDTs and MIC are significantly higher than in not‐Polissia. In Polissia, the prevalence rates of NDTs and MIC are among the highest in Europe. The debate concerning the teratogenic impact of chronic exposures to low levels of ionizing radiation was re‐ignited by our 2010 report. Health agencies uphold the notion that exposure to Chornobyl radiation levels are too low to be teratogenic, which is inconsistent with our observations. Further investigations in Rivne by international teams can, we believe, contribute facts to the ongoing debate. Our monitoring system, experience and data can facilitate concurrent investigations of teratogenic risks from exposures to other sources of ionizing radiation, alcohol, folate, and zinc deficiencies, among other risk factors. Study of genomic impacts can likewise be undertaken. 相似文献
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In this paper, a vertical distribution of 137Cs in undisturbed soil was investigated experimentally and theoretically. Soil samples were taken from the surroundings of the city of Kragujevac in central Serbia during spring-summer of 2001. The sampling locations were chosen in such a way that the influence of soil characteristics on depth distribution of 137Cs in soil could be investigated. Activity of 137Cs in soil samples was measured using a HpGe detector and multi-channel analyzer. Based on vertical distribution of 137Cs in soil which was measured for each of 10 locations, the diffusion coefficient of 137Cs in soil was determined. In the next half-century, 137Cs will remain as the source of the exposure. Fifteen years after the Chernobyl accident, and more than 30 years after nuclear probes, the largest activity of 137Cs is still within 10 cm of the upper layer of the soil. This result confirms that the penetration of 137Cs in soil is a very slow process. Experimental results were compared with two different Green functions and no major differences were found between them. While both functions fit experimental data well in the upper layer of soil, the fitting is not so good in deeper layers. Although the curves obtained by these two functions are very close to each other, there are some differences in the values of parameters acquired by them. 相似文献
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用放射化学分析方法,对新疆核试验场周围10个调查区和远离核试验场位于上风向的5个对照区采取的土壤样品进行了90Sr、137Cs分析测定。核试验场周围调查区土壤中90Sr累积平均沉降量为1.5×103Bqm-2,137Cs为4.9×103Bqm-2;对照区90Sr累积平均沉降量为1.3×103Bqm-2,137Cs为3.9×103Bqm-2。调查区和对照区表层土壤中州90Sr,137Cs放射性平均水平无显著性差异。通过估算得出了调查区90Sr、137Cs对居民产生约定有效剂量当量分别为78.3μSv(集体剂量当量负担为23.9人·sv)和270μSv(集体剂量当量负担为82.3人·sv),对照区分别为70.5μSv,(集体剂量当量负担为14.1人·sv)和220μSv(集体剂量当量负担为14.1人·sv)。两个地区居民受到来自核试验产生的90Sr和137Cs给予人体的内照射剂量当量负担基本上是一样的。可认为90Sr、137Cs对新疆核试验场周围没有造成严重的局部污染。对居民的身体健康不致于产生不良影响。 相似文献
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目的:探讨转化生长因子(TGF)-β1对香烟诱导的大鼠肺泡巨噬细胞γ-谷氨酰半胱氨酸合酶(γ-GCS)和活化蛋白(AP)-1亚单位c-fos mRNA及其蛋白表达的影响。方法:通过支气管肺泡灌洗获取大鼠肺泡巨噬细胞,随机分为对照组、香烟组和TGF-β1组。TGF-β1组加入终浓度为3 μg/L的TGF-β1,2 h后除对照组外,余2组均加入香烟烟雾提取物,对照组加入磷酸盐缓冲液。分别用逆转录聚合酶链式反应(RT-PCR)和免疫细胞化学方法检测肺泡巨噬细胞中γ-GCSh(重链亚单位)及c-fos mRNA和蛋白的表达。结果:香烟组γ-GCSh和c-fos mRNA及其蛋白表达水平显著高于对照组(分别P<0.05,P<0.01)。TGF-β1组γ-GCSh mRNA及其蛋白表达水平明显低于香烟组(均P<0.01);而c-fos mRNA及其蛋白表达水平明显高于香烟组(均P<0.01)。结论:转化生长因子-β1参与香烟所致慢性阻塞性肺疾病肺氧化/抗氧化失衡的发病机制。 相似文献
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Human multiple myeloma cells express peroxisome proliferator-activated receptor gamma and undergo apoptosis upon exposure to PPARgamma ligands 总被引:8,自引:0,他引:8
Multiple myeloma is essentially an incurable malignancy and it is therefore of great interest to develop new therapeutic approaches. We previously reported that human B cell-lymphomas express the nuclear receptor peroxisome proliferator-activated receptor gamma (PPARgamma) and are killed by PPARgamma ligands. Herein, we investigate the therapeutic potential of PPARgamma ligands for multiple myeloma. The human multiple myeloma cell lines ANBL6 and 8226 express PPARgamma mRNA and protein. The PPARgamma ligands, 15-deoxy-Delta12,14-prostaglandin J2 (15d-PGJ2) and ciglitazone, induced multiple myeloma cell apoptosis as determined by terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling (TUNEL) assay, loss of mitochondrial membrane potential, and caspase activation. Importantly, the ability of PPARgamma ligands to kill both multiple myeloma cell lines was not abrogated by Interleukin-6 (IL-6), a multiple myeloma growth survival factor. Finally, the RXR ligand 9-cis retinoic acid (9-cis RA) in combination with PPARgamma ligands greatly enhanced multiple myeloma cell killing. These new findings support that PPARgamma ligands may represent a novel therapy for multiple myeloma. 相似文献
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Virus infectivity in samples of culture medium or suspensions of animal tissue which are required for interferon assay can be rapidly and conveniently inactivated by overnight incubation with beta-propiolactone (BPL). As BPL hydrolyses spontaneously samples can be assayed with no further treatment. BPL does not affect the interfering activity of alpha, beta or gamma mouse interferons. 相似文献
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应用制霉菌素穿孔全细胞电压钳技术.在急性分离的大鼠骶髓后连合核(SDCN)神经元上,研究抑制性氨基酸诱导的反应的电生理学和药理学特性。当钳制电压为-40mV时,γ-氨基丁酸(GABA)、甘氨酸(Gly)和牛磺酸(Tau)均诱导产生内向电流。它们的EC50值分别是GABA5.2×10-5M,Gly4.0×10-5M及Tau1.6×10-4M。其Hill系数分别为GABA1.21,Gly1.27和Tau1.23。所有这些电流均在膜电位为-1.8mV左右时翻转。此外.Tau和Gly反应问还存在很强的交叉脱敏。结果提示,GABAA,Gly和Tau作为递质,通过受体Cl-通道复合体.在调节SDCN社经元伤害性传递中可能有重要作用。 相似文献