Are African-American nuclear workers at lower mortality risk than Caucasians?

This study investigated disparities in worker mortality across race at the Savannah River site (SRS) nuclear facility in Aiken, South Carolina. Standardized mortality ratios were calculated stratified by race (Caucasian, African-American) and gender for specific causes of death, and by race, gender, duration of employment, and follow-up for overall mortality. Race-specific standardized mortality ratios for African-American male workers generally were lower than those for Caucasian male workers, although both groups showed strong healthy worker effects. Nevertheless, African-American male workers generally had higher absolute mortality rates. Understanding why SRS African-American male workers are substantially healthier than their reference population as compared with Caucasian male workers but are less healthy in absolute terms than the SRS Caucasian male workers may provide clues for prevention or intervention. Further, the standardized mortality ratios at the SRS were lower than at the Hanford and Oak Ridge nuclear facilities, which warrants investigation.     

Chernobyl vis-à-vis the nuclear future: an international perspective

The paper aims to provide an international perspective on the consequences of the Chernobyl accident vis-à-vis the future development of the use of nuclear energy for peaceful purposes. It describes the major international initiatives that were undertaken over the years in order to quantify the consequences of the Chernobyl accident, and also analyzes the impact of the accident on the development of nuclear energy taking account of the perception of its consequences. The paper revisits the historical saga flowing since the fateful explosion at the Chernobyl Nuclear Power Plant in the Ukraine 20 y ago. It looks at some of the misunderstandings about the consequences of the accident and explores the worldwide nuclear stagnation that followed Chernobyl, surveying the negative public reaction and also the possibilities of a nuclear revival. It finally searches for a way forward, concluding that an effective international nuclear safety regime is urgently needed with the purpose of preventing catastrophes like Chernobyl from occurring and also that the Chernobyl consequences need to be readdressed properly. The paper concludes with an appeal to the radiation protection community to resolve once and for all the difficult issues of attributing health effects to low-level radiation exposure.     

An assessment of radiation doses at an educational institution 57.8 km away from the Fukushima Daiichi nuclear power plant 1 month after the nuclear accident

Objectives  

On 11 March 2011, the Great East Japan Earthquake occurred. Due to this earthquake and subsequent tsunami, malfunctions occurred at the Fukushima Daiichi nuclear power plant. Radioactive material even reached the investigated educational institution despite being 57.8 km away from the power station. With the goal of ensuring the safety of our students, we decided to carry out a risk assessment of the premises of this educational institution by measuring radiation doses at certain locations, making it possible to calculate estimated radiation accumulation.     

Is knowledge important? Empirical research on nuclear risk communication in two countries

Increasing audience knowledge is often set as a primary objective of risk communication efforts. But is it worthwhile focusing risk communication strategies solely on enhancing specific knowledge? The main research questions tackled in this paper were: (1) if prior audience knowledge related to specific radiation risks is influential for the perception of these risks and the acceptance of communicated messages and (2) if gender, attitudes, risk perception of other radiation risks, confidence in authorities, and living in the vicinity of nuclear/radiological installations may also play an important role in this matter. The goal of this study was to test empirically the mentioned predictors in two independent case studies in different countries. The first case study was an information campaign for iodine pre-distribution in Belgium (N = 1035). The second was the information campaign on long-term radioactive waste disposal in Slovenia (N = 1,200). In both cases, recurrent and intensive communication campaigns were carried out by the authorities aiming, among other things, at increasing specific audience knowledge. Results show that higher prior audience knowledge leads to more willingness to accept communicated messages, but it does not affect people’s perception of the specific risk communicated. In addition, the influence of prior audience knowledge on the acceptance of communicated messages is shown to be no stronger than that of general radiation risk perception. The results in both case studies suggest that effective risk communication has to focus not only on knowledge but also on other more heuristic predictors, such as risk perception or attitudes toward communicated risks.     

Zinc-suppressed inflammatory cytokines by induction of A20-mediated inhibition of nuclear factor-κB

ObjectiveChronic generation of inflammatory cytokines and reactive oxygen species are implicated in atherosclerosis, aging, cancers, and other chronic diseases. We hypothesized that zinc induces A20 in premonocytic, endothelial, and cancer cells, and A20 binds to tumor necrosis factor (TNF)-receptor associated factor, and inhibits Iκ kinase-α (IKK-α)/nuclear factor-κB (NF-κB), resulting in downregulation of TNF-α and interleukin-1β (IL-1β).MethodsTo test this hypothesis, we used HL-60, human umbilical vein endothelial cells, and SW480 cell lines under zinc-deficient and zinc-sufficient conditions in this study. We measured oxidative stress markers, inflammatory cytokines, A20 protein and mRNA, A20–FRAF-1 complex, and IKK-α/NF-κB signaling in stimulated zinc-deficient and zinc sufficient cells. We also conducted antisense A20 and siRNA studies to investigate the regulatory role of zinc in TNF-α and IL-1β via A20.ResultsWe found that zinc increased A20 and A20–tumor necrosis factor-receptor associated factor-1 complex, decreased the IKK-α/NF-κB signaling pathway, oxidative stress markers, and inflammatory cytokines in these cells compared with zinc-deficient cells. We confirmed that zinc-induced A20 contributes to downregulation of TNF-α and IL-1β by antisense and short interfering RNA A20 studies.ConclusionOur studies suggest that zinc suppresses generation of NF-κB–regulated inflammatory cytokines by induction of A20.     

Is in vivo nuclear magnetic resonance spectroscopy currently a quantitative method for whole-body carbohydrate metabolism?

In vivo nuclear magnetic resonance (NMR) spectroscopy is a powerful tool for noninvasive metabolic research. NMR studies of tissue glycogen metabolism and glucose utilization have generated results with major implications for normal glucose homeostasis and the pathophysiology of type 2 diabetes mellitus. A key question for clinicians and physiologists reading these highly technical studies is: How accurate for whole-body carbohydrate metabolism is NMR spectroscopy? We review this topic and discuss technical, metabolic, and interpretive factors that may limit quantitative accuracy of this modality. We conclude that seeing is not yet believing regarding in vivo NMR spectroscopy; there are still important limitations to quantification of whole-body carbohydrate metabolism.     

Musca domestica pupae lectin improves the immunomodulatory activity of macrophages by activating nuclear factor-κB

In this study, Musca domestica pupae lectin (MPL) was screened for its immunomodulatory effect on macrophages. The phagocytosis of macrophages was improved significantly when they were treated with MPL: remarkable changes were observed in the morphology of the cells, the metabolic abilities of DNA and RNA were enhanced, and the production of hepatin was increased. Meanwhile, compared with the control group, not only the mRNA expressions of tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), and interferon-γ (IFN-γ) in macrophages, but also the productions of proteins, were strongly induced by MPL; these effects were inhibited by pyrrolidine dithiocarbamate. Further study suggested that MPL could increase the nuclear factor-κB (NF-κB) p65 level in the nucleus. Overall, these results indicate that the improving immunomodulatory activity induced by MPL is mainly due to the increasing productions of TNF-α, IL-6, and IFN-γ and that the activation of macrophage by MPL is partly mediated via the NF-κB pathway.     

Radioactivity appearing at landfills in household trash of nuclear medicine patients: much ado about nothing?

The U.S. NRC in 1997 removed its arbitrary 1.11 GBq (30 mCi) rule, which had been in existence for almost 50 y, and now many more patients receiving radionuclide therapy in nuclear medicine can be treated as outpatients. However, another problem has the potential to limit the short-lived reality of outpatient treatment unless nuclear medicine practitioners and the health physics community gets involved. Radioactive articles in the household trash of nuclear medicine patients are appearing at solid waste landfills that have installed radiation monitors to prevent the entry of any detectable radioactivity, and alarms are going off around the country. These monitors are set to alarm at extremely low activity levels. Some states may actually hold licensees responsible if a patient's radioactive household trash is discovered in a solid waste stream; this is another major reason [along with continued use of the 1.11 GBq (30 mCi) rule] why many licensees are still not releasing their radionuclide therapy patients. This is in spite of the fact that the radioactivity contained in released nuclear medicine therapy patients, let alone the much lower activity level contained in their potentially radioactive household wastes, poses a minimal hazard to the public health and safety or to the environment. Currently, there are no regulations governing the disposal of low-activity, rapidly-decaying radioactive materials found in the household trash of nuclear medicine patients, the performance of landfill radiation monitors, or the necessity of spectrometry equipment. Resources are, therefore, being unnecessarily expended by regulators and licensees in responding to radiation monitor alarms that are caused by these unregulated short-lived materials that may be mixed with municipal trash. Recommendations are presented that would have the effect of modifying the existing landfill regulations and practices so as to allow the immediate disposal of such wastes.     

Dietary supplementation with geranylgeraniol suppresses lipopolysaccharide-induced inflammation via inhibition of nuclear factor-κB activation in rats

Purpose

The isoprenoid geranylgeraniol (GGOH) inhibits nuclear factor-kappa B (NF-κB) activation in the liver, yet the mechanism remains unclear. We investigated the modulation and inhibition of lipopolysaccharide (LPS)-induced NF-κB signaling in the liver of rats fed a GGOH-supplemented diet.

Methods

Rats were fed a diet supplemented with or without GGOH for 10 days. Rats were then intraperitoneally injected with 0.5 mg/kg LPS or vehicle (sterilized saline) and fasted for 18 h. Plasma levels of the inflammatory cytokines tumor necrosis factor (TNF)-α, interleukin (IL)-1β, and IL-6, and the liver damage indicators alanine and aspartate aminotransferases (ALT and AST) were assessed. Liver mRNA and proteins were assayed for changes in NF-κB target genes and signal transduction genes.

Results

Rats fed a high-dose, GGOH-supplemented diet showed significantly lower levels of plasma inflammatory cytokines and ALT and AST activities. In the liver, GGOH significantly suppressed NF-κB activation and mRNA expression of its pro-inflammatory target genes. Furthermore, GGOH supplementation substantially suppressed mRNA expression of signal transducer genes upstream of the IκB kinase complex. Western blotting of liver extracts further demonstrated the substantial decrease in total IL-1 receptor-associated kinase 1 (IRAK1) and TNF receptor-associated factor 6 (TRAF6), leading to lower signal transduction and inhibition of NF-κB after LPS.

Conclusion

A 10-day, high-dose, GGOH-supplemented diet was sufficient to inhibit LPS-induced inflammation and activation of NF-κB in rat livers. GGOH significantly modulated NF-κB signaling molecules, inhibiting its signal transduction and activation in the liver, thus protecting against liver damage.     

The Australian radiation protection and nuclear safety agency megavoltage photon thermoluminescence dosimetry postal audit service 2007–2010

The Australian radiation protection and nuclear safety agency (ARPANSA) has continuously provided a level 1 mailed thermoluminescence dosimetry audit service for megavoltage photons since 2007. The purpose of the audit is to provide an independent verification of the reference dose output of a radiotherapy linear accelerator in a clinical environment. Photon beam quality measurements can also be made as part of the audit in addition to the output measurements. The results of all audits performed between 2007 and 2010 are presented. The average of all reference beam output measurements calculated as a clinically stated dose divided by an ARPANSA measured dose is 0.9993. The results of all beam quality measurements calculated as a clinically stated quality divided by an ARPANSA measured quality is 1.0087. Since 2011 the provision of all auditing services has been transferred from the Ionizing Radiation Standards section to the Australian Clinical Dosimetry Service (ACDS) which is currently housed within ARPANSA.     

Is Yucca Mountain a long-term solution for disposing of US spent nuclear fuel and high-level radioactive waste?

On 26 January 2012, the Blue Ribbon Commission on America's Nuclear Future released a report addressing, amongst other matters, options for the managing and disposal of high-level waste and spent fuel. The Blue Ribbon Commission was not chartered as a siting commission. Accordingly, it did not evaluate Yucca Mountain or any other location as a potential site for the storage or disposal of spent nuclear fuel and high-level waste. Nevertheless, if the Commission's recommendations are followed, it is clear that any future proposals to develop a repository at Yucca Mountain would require an extended period of consultation with local communities, tribes and the State of Nevada. Furthermore, there would be a need to develop generally applicable regulations for disposal of spent fuel and high-level radioactive waste, so that the Yucca Mountain site could be properly compared with alternative sites that would be expected to be identified in the initial phase of the site-selection process. Based on what is now known of the conditions existing at Yucca Mountain and the large number of safety, environmental and legal issues that have been raised in relation to the DOE Licence Application, it is suggested that it would be imprudent to include Yucca Mountain in a list of candidate sites for future evaluation in a consent-based process for site selection. Even if there were a desire at the local, tribal and state levels to act as hosts for such a repository, there would be enormous difficulties in attempting to develop an adequate post-closure safety case for such a facility, and in showing why this unsaturated environment should be preferred over other geological contexts that exist in the USA and that are more akin to those being studied and developed in other countries.     

High-fat diet blunts activation of the nuclear factor-κB signaling pathway in lipopolysaccharide-stimulated peritoneal macrophages of Wistar rats

ObjectiveThe present study was designed to investigate the effect of a high-fat diet (HFD) on the inflammatory response of peritoneal macrophages.MethodsMale Wistar rats were fed a control diet (n = 12) or an HFD (n = 12) for 12 wk. After euthanasia, peritoneal macrophages were collected and stimulated (or not) with lipopolysaccharide (LPS). Results from the assays using peritoneal macrophages were analyzed with one-way analysis of variance or an equivalent non-parametric test. The level of significance adopted was 0.05.ResultsConsumption of the HFD was associated with significant increases in weight gain and fat depots (P < 0.05). Despite having no influence in systemic markers of inflammation, such as interleukin (IL)-6, tumor necrosis factor-α, and plasminogen activator inhibitor-1, the HFD intake significantly decreased insulin sensitivity, as evaluated by the homeostasis model assessment index (P < 0.05). A decreased production of IL-1β, IL-6, IL-10, and nitric oxide in response to the LPS stimulation was observed in peritoneal macrophages from the HFD group (P < 0.05). Also, in HFD-fed animals, LPS incubation did not increase IL-1β and IL-6 mRNA expression (P < 0.05). These effects were associated with an attenuation of IκB inhibitor kinase-β phosphorylation and nuclear factor-κB activation in response to LPS and with a failure to decrease IκB inhibitor-α expression (P < 0.05).ConclusionChronic consumption of an HFD decreased the LPS-induced inflammatory response of peritoneal macrophages, which was associated with a downregulation of the nuclear factor-κB signaling pathway.