Long-term Radiation Exposure Research Articles

In-situ strain analysis of potential habitat composites exposed to a simulated long-term lunar radiation exposure

NASA is studying the effects of long-term space radiation on potential multifunctional composite materials for habitats to better determine their characteristics in harsh space environments. Two epoxy-matrix composite materials were selected for the study and were mounted in a test stand that simulated the biaxial stresses of a pressure vessel wall. The samples in the test stand were exposed to radiation at fast (0.1478krad/s) and slow (0.0139krad/s) dose rates, and the strain and temperature were recorded during the exposure. During a fast dose rate exposure, negative strain was recorded, decreasing with time, an indication of matrix shrinkage. Given previous radiation studies of polymers, this is expected to be a result of radiation-induced crosslinking in the epoxy matrix. However, with a slow dose rate, the materials exhibited a positive strain that increased with time, corresponding to stretching of the materials. This result is consistent with scission or degradation of the matrix occurring, possibly due to oxidative degradation.

The risk of acute myocardial infarction development in long-term radiation exposure

The risk of acute myocardial infarction development in long-term radiation exposure

Study protocol for the Fukushima Health Management Survey.

BackgroundThe accidents that occurred at the Fukushima Daiichi Nuclear Power Plant after the Great East Japan Earthquake on 11 March 2011 have resulted in long-term, ongoing anxiety among the residents of Fukushima, Japan. Soon after the disaster, Fukushima Prefecture launched the Fukushima Health Management Survey to investigate long-term low-dose radiation exposure caused by the accident. Fukushima Medical University took the lead in planning and implementing this survey. The primary purposes of this survey are to monitor the long-term health of residents, promote their future well-being, and confirm whether long-term low-dose radiation exposure has health effects. This report describes the rationale and implementation of the Fukushima Health Management Survey.MethodsThis cohort study enrolled all people living in Fukushima Prefecture after the earthquake and comprises a basic survey and 4 detailed surveys. The basic survey is to estimate levels of external radiation exposure among all 2.05 million residents. It should be noted that internal radiation levels were estimated by Fukushima Prefecture using whole-body counters. The detailed surveys comprise a thyroid ultrasound examination for all Fukushima children aged 18 years or younger, a comprehensive health check for all residents from the evacuation zones, an assessment of mental health and lifestyles of all residents from the evacuation zones, and recording of all pregnancies and births among all women in the prefecture who were pregnant on 11 March. All data have been entered into a database and will be used to support the residents and analyze the health effects of radiation.ConclusionsThe low response rate (<30%) to the basic survey complicates the estimation of health effects. There have been no cases of malignancy to date among 38 114 children who received thyroid ultrasound examinations. The importance of mental health care was revealed by the mental health and lifestyle survey and the pregnancy and birth survey. This long-term large-scale epidemiologic study is expected to provide valuable data in the investigation of the health effects of low-dose radiation and disaster-related stress.

Chapter 7. Neuroimaging

Chapter 7. Neuroimaging

Potential Long-Term Complications of Endovascular Stent Grafting for Blunt Thoracic Aortic Injury

Blunt thoracic aortic injury (BTAI) is a rare, but lethal, consequence of rapid deceleration events. Most victims of BTAI die at the scene of the accident. Of those who arrive to the hospital alive, expedient aortic intervention significantly improves survival. Thoracic endovascular aortic repair (TEVAR) has been accepted as the standard of care for BTAI at many centers, primarily due to the convincing evidence of lower mortality and morbidity in comparison to open surgery. However, less attention has been given to potential long-term complications of TEVAR for BTAI. This paper focuses on these complications, which include progressive aortic expansion with aging, inadequate stent graft characteristics, device durability concerns, long-term radiation exposure concerns from follow-up computed tomography scans, and the potential for (Victims of Modern Imaging Technology) VOMIT.

Highlights of This Issue

In the United States, primary care physicians play a central role in implementing cancer screening guidelines because many cancer screens require a referral to a specialist. Yabroff and colleagues assessed primary care physicians' use of system strategies in cancer screening, including screening reminders, screening rate performance reports, and implementation of practice guidelines. They found that only 10% of primary care physicians in the United States used systems strategies to support breast, cervical, and colorectal cancer screening. This is the case despite extensive evidence on the effectiveness of these strategies to improve patient care. This report highlights the need for more primary care practices to implement systems strategies to improve the use and quality of cancer screening.The Risk for Ovarian Malignancy Algorithm (ROMA) is a tool that uses serum levels of human epididymis protein 4 (HE4) and CA125 to determine the risk of epithelial ovarian cancer (EOC) in patients with a pelvic mass. In this study, Bandiera and colleagues analyzed the diagnostic and prognostic value of HE4 and CA125 alone or combination (ROMA) to evaluate EOC risks. In both pre- and postmenopausal women, the high specificity of HE4 helped discriminate benign cysts from EOC, and the high sensitivity of CA125 was important for detecting EOC. Elevated HE4 and ROMA were both independent prognostic factors for shorter overall survival. Future multicenter studies will be necessary for further assessment of HE4, CA125, and ROMA to monitor EOC.Although solar UV radiation is a risk factor for cataract formation, the major health benefit of UV radiation exposure is the production of vitamin D, which is implicated in protection against several cancers. In this population-based case–control study, Lurie and colleagues examined the association of ovarian cancer risk with cataract formation as an indicator of high long-term UV radiation exposure. The authors report that a history of cataracts was significantly associated with reduced risk for ovarian cancer, adding indirect evidence to the hypothesis that lifetime vitamin D exposure may be inversely associated with the risk of ovarian cancer.Genetic polymorphisms of Toll-like receptors (TLR) may influence the outcome of Helicobacter pylori infection and play roles in gastric cancer. Zeng and colleagues conducted a population-based study to screen the genetic variants of TLR2 and TLR5 and evaluate their associations with gastric cancer. The authors detected 9 genetic variants within the promoters and exons of TLR2 and TLR5 that either decreased or increased the risk of gastric cancer and/or H. pylori infection. These findings suggest that TLR2 and TLR5 gene variants may influence H. pylori–related gastric cancer carcinogenesis.

Impact assessment of long-term chronic radiation exposure on plant populations

Studies that examine biological effects on non-human biota in natural settings provide a unique opportunity for obtaining information about the potential biological hazard associated with radioactive contamination. The results of long-term field study in the Bryansk Region, Russia, affected by the Chernobyl accident are discussed. Plant populations growing in areas with relatively low levels of pollution are characterized by the increased level of both cytogenetic alterations and genetic diversity. In particular, radioactive contamination of the plants’ environment activates genetic mechanisms, changing a population’s resistance to exposure. However, there are radioecological situations where enhanced radioresistance has not evolved or has not persisted. A development of a system for protection of the environment from ionizing radiation should be based on a clear understanding of these effects and their contribution to response of populations.

Preferred management option for small renal masses: laparoscopic partial nephrectomy

Preferred management option for small renal masses: laparoscopic partial nephrectomy

System performance of phosphor screen coupled CMOS imager for long-term radiation exposure

We present the performances of a scintillator coupled CMOS APS imager under cumulative X-ray exposure conditions in terms of the modulation transfer function (MTF), noise power spectrum, and detective quantum efficiency (DQE). An industrial X-ray generator with the condition of 50 kVp/500 μA was used to take cumulative exposure conditions. The experimental results show that the MTF and DQE exponentially degraded because of direct X-ray exposure of the imager through the scintillator. For the given scintillator and radiation exposure, the system performance of the scintillator coupled CMOS APS imager can be predicted.

NF-κB-MediatedHER2Overexpression inRadiation-Adaptive Resistance

The molecular mechanisms governing acquired tumor resistance during radiotherapy remain to be elucidated. In breast cancer patients, overexpression of HER2 (human epidermal growth factor receptor 2) is correlated with aggressive tumor growth and increased recurrence. In the present study, we demonstrate that HER2 expression can be induced by radiation in breast cancer cells with a low basal level of HER2. Furthermore, HER2-postive tumors occur at a much higher frequency in recurrent invasive breast cancer (59%) compared to the primary tumors (41%). Interestingly, NF-kappaB is required for radiation-induced HER2 transactivation. HER2 was found to be co-activated with basal and radiation-induced NF-kappaB activity in radioresistant but not radiosensitive breast cancer cell lines after long-term radiation exposure, indicating that NF-kappaB-mediated HER2 overexpression is involved in radiation-induced repopulation in heterogeneous tumors. Finally, we found that inhibition of HER2 resensitizes the resistant cell lines to radiation. Since HER2 is shown to activate NF-kappaB, our data suggest a loop-like HER2-NF-kappaB-HER2 pathway in radiation-induced adaptive resistance in breast cancer cells.

Analysis of rodent populations in technogenically transformed areas (with reference to Apodemus (S.) uralensis from the EURT zone)

It is shown that the response of rodent populations to acute and chronic irradiation depends on its functional structure, i.e., on specific features of animals with two alternative types of ontogenetic development. Upon acute irradiation, sexually immature young of the year (animals with the second type of ontogeny) are most radioresistant. Exposure to chronic irradiation, as in the zone of the Eastern Ural Radioactive Trace (EURT), leads to an increase in the proportion of mature young of the year (animals with the first type of ontog- eny), which are the most radiosensitive part of the population. The abundance and fecundity of mice in the impact zone are consistently higher than in the background zone, which improves the adaptive potential of the population. The role of species ecological specialization and configuration of the contaminated zone in the for- mation of migrant rodent population is emphasized. It is concluded that a high migration activity allows the pigmy wood mouse (a radiosensitive species) to avoid long-term radiation exposure. DOI: 10.1134/S1067413608040085

The common reed in the Chernobyl accident Exclusion Zone: morphometric, cytogenetic and parasitologic studies

The main purposes of our research were to assess the abnormality rate of common reed’s reproductive organs to reveal possible morphological changes, to evaluate the chromosome aberration rate in root meristems and to analyse the morbidity of plants by the ergot (Claviceps purpurea) and by gall-producing arthropods in water bodies with different levels of radioactive contamination within the Chernobyl accident Exclusion Zone. The main water bodies were Glubokoye Lake and Dalekoye-1 Lake, Azbuchin Lake and Yanovsky Crawl, cooling pond of the Chernobyl NPP as well as Pripyat River and Uzh River. Average absorbed dose rate was found from 0.022 to 0.120 Gy/year for the reed from littoral and sublittoral zone of investigated water bodies: Chernobyl NPP cooling pond (0.022); Yanovsky Crawl (0.037); Azbuchin Lake (0.046); Dalekoe-1 Lake (0.053) and Glubokoe Lake (0.120). The highest rate of the absorbed dose was found for the lakes of the left-bank dammed floodplain of the Pripyat River (Dalekoe and Glubokoye), which are the most radioactive contaminated territory within the Exclusion Zone. Performed studies indicate the existence of authentic morphometric and morphological abnormalities of reproductive organs of the common reed. The most typical abnormalities are decreasing of average reed panicle length and width, decreasing of the number of flowers of a low-level blossom cluster and also modification of the shape and colour of the seeds in comparison with standard parameters for the common reed of Europe’s middle latitude. The highest chromosome aberrations rate in root meristems of the common reed (17.8-10.8 %) were registered in plants from lakes within the left-bank flood lands of the Pripyat River, the lowest one (4.5-2.2 %) - in plants from the Pripyat River and Uzh River. The high level of parasitic fungi (Claviceps purpurea) and gall-producing arthropods (Steneotarsonemus phragmitidis and S. gibber) lesion in the most contaminated water bodies within the Chernobyl NPP accident exclusion zone was registered. The damage events of common reed by larvae of gall fly of family Chloropidae, genus Lipara has been considered as well. Above mentioned phenomenon may testify upon the decreasing of the parasitical stability of the common reed under impact of long-term radiation exposure.

Occupational-related SCC of the Hand-A Case of Long-term Radiation Exposure

Radiation exposure may induce skin and organic diseases including cancers. Squamous cell carcinoma of skin caused by ionizing radiation was not common especially in occupational field. A case of radiologic technologist was presented here with a radiation dermatitis of his hand which induced by long term of ionizing radiation exposure while diagnostic examinations and therapeutic procedures. The pathology of wound had proved to be squamous cell carcinoma, and he then received wide excision and skin graft at our hospital. The functional outcome was satisfactory and he returned to work with no handicap. From this case, appropriate protections was emphasized for lengthy procedure while working under possible ionizing radiation as well as careful monitoring and periodic examinations were strongly recommended.

Chelating Agents Used for Plutonium and Uranium Removal in Radiation Emergency Medicine

The prospects of using chelating agents for increasing the excretion of actinides are reviewed. The removal of plutonium by chelating agents is of great importance because plutonium is extremely dangerous and induces cancer due to radiation toxicity. Similarly, uranium is a radionuclide, which causes severe renal dysfunction within a short time period due to chemical toxicity. It may also induce cancers such as leukemia and osteosarcoma in cases of long-term internal radiation exposure. Investigations on chelating agents for the removal of plutonium were initiated in the 1960's and 1970's. Diethylenetriaminepentaacetic acid (DTPA) is recognized as a chelating agent that accelerates the excretion of plutonium in early treatment after an accident. Thereafter, there has long been an interest in finding new chelating agents with radionuclide removal properties for use in therapy, and many chelating agents such as 3,4,3-LIHOPO and CBMIDA have been studied for their ability to remove plutonium and uranium. Recently, the focus has turned to drugs that have been used successfully in the treatment of a variety of other diseases, for example the iron chelating drug deferiprone or 1,2-dimethyl-3-hydroxypyrid-4-one (L1), which is used in thalassaemia and ethane-1-hydroxy-1,1-bisphosphonate (EHBP), which is used in osteoporosis. Within this context, it is important to examine the clinical use of these two drugs as well as the properties of the experimental chelators 3,4,3-LIHOPO and CBMIDA in order to identify possible uses in the treatment of radiation workers contaminated with plutonium and uranium.

An instantaneous photomultiplier tube gain-tuning method for PET or gamma camera detectors using an LED network

A photomultiplier tube (PMT) gain can change with many environmental factors, such as room temperature, patient load, short-term or long-term radiation exposure, and time. Unbalanced PMT gains degrade the image resolution and quality in a positron emission tomography (PET) camera or a gamma camera. This paper presented a new method to instantaneously recover the original manufacture PMT gain setting using a blue light-emitting diode (LED) network. Each LED shines directly into the center of a scintillation crystal block from the PMT side, and the light is collected by the surrounding PMTs. The gain tuning is done by changing the gains of these surrounding PMTs or their following amplifiers to have the same signal output. An LED has well-known problems of large light-yield varieties and is very sensitive to temperature. To overcome these problems, the light outputs of two neighboring LEDs are aligned first by a shared PMT. Each LED flashes at 250-KHz pulse rate, the data acquisition for the gain tuning can be finished within a very short time so the LED temperature effect can be ignored. The amount of LED light output is set as close as possible to the amount of scintillation light by programming the width or height of the pulses; therefore, the same electronics can be used for data acquisition and tuning. We estimated a 12 module PET camera with 924 PMTs in a PMT-quadrant-sharing design can be tuned in 1 min.

Urinary 8-Hydroxydeoxyguanosine in Belarussian Children Relates to Urban Living Rather Than Radiation Dose After the Chernobyl Accident: A Pilot Study

As a result of the Chernobyl accident in 1986, exposure to radioactive cesium is still a concern in the contaminated regions of Belarus. We tested the hypothesis that long-term radiation exposure from the Chernobyl accident might increase the urinary excretion of the oxidative stress marker, 8-hydroxydeoxyguanosine (8-OHdG), in Belarussian children. Urinary 8-OHdG was determined in two groups of children (-n = 31 and n = 46) -living in contaminated and uncontaminated areas of Belarus, respectively (the majority of the unexposed children lived in the capital Minsk). The children from the contaminated areas had a significantly higher annual summary effective dose but significantly lower urinary 8-OHdG levels than the children from the uncontaminated areas. Unexpectedly, children living in uncontaminated urban areas had significantly higher urinary 8-OHdG levels than children living in uncontaminated rural areas. There was no statistically significant effect of sex or body mass index on urinary 8-OHdG, but there was a weak significant inverse correlation to age as well as to the annual summary effective dose. These findings suggest that radiation from the Chernobyl accident is now a less important contributor to oxidative stress in Belarussian children than urban living.

Long-term global earth surface ultraviolet radiation exposure derived from ISCCP and TOMS satellite measurements

A long-term (1983–2000) global dataset of Earth’s surface daily-integrated UV exposure was developed from a combination of ISCCP-D1 3 h reflectance measurements (in order to resolve the diurnal variation of cloud conditions) and TOMS total ozone amount. The inversion algorithm developed in our previous study was employed with modifications addressing the conversion of visible reflectance to UV albedo and narrowband UV albedo to broadband albedo over the range of 280–400 nm. Validation of the product was carried out using ground-based measurements at six stations. In general, good agreements between the estimated and measured daily UV exposure are found at most stations; the relative mean and root mean square (RMS) difference varies from 3 to 14% and from 20 to 45%, respectively. Among the stations, San Diego has a fairly low mean difference (9%) and the lowest RMS difference (33%), owing to the prevailing clear sky or uniform cloud cover condition. The RMS difference increases with cloud amount, which is largely caused by mismatch between satellite and ground-based measurements. The effect of diurnal variation in atmospheric opacity associated primarily with cloud on the estimation of daily erythemal UV doses is investigated with both ground-based measurements and ISCCP-D1 data. It is found that daily erythemal UV doses estimated from only a noontime satellite “snapshot” may incur errors larger than 20%, which may be reduced for long-term averaging.

Genetic diversity in three perennial grasses from the Semipalatinsk nuclear testing region of Kazakhstan after long-term radiation exposure

The extent and structure of the genetic diversity of plant populations from the Semipalatinsk region of Kazakhstan, adjacent to a former major nuclear test site, have been studied using RAPD (Random Amplified Polymorphic DNA) marker analyses. The DNAs from three perennial species, Stipa capillata, Hordeum bogdanii, and Agropyron pectinatum, each collected from heavily (HPZ), moderately (MPZ) and lightly polluted zones (LPZ) have been analyzed using RAPDs. The results show a significantly higher level of variability in plants collected from the highest radiation pollution area compared with the moderately and lightly radiation contaminated zones for A. pectinatum and H. bogdanii. Variation was five times as higher in heavily exposed H. bogdanii, and two times higher in A. pectinatum populations compared to their lightly contaminated populations. H. bogdanii appears to be very sensitive to radiation and as such is a good indicator species for mapping radiation pollution at nuclear test sites or nuclear accidents.

Keratoelastoidosis Marginalis

Background: Keratoelastoidosis marginalis is a rare disease that is a variant of solar elastosis. Long-term ultraviolet radiation exposure and chronic trauma secondary to manual labor are considered to be inciting factors. Objective: To outline the clinical and histological features of this disorder. Methods: We report two cases and review the literature. Results: Both patients had persistence of their disease despite multiple topical treatment regimens. Conclusion: Keratoelastoidosis marginalis is a chronic and progressive disease that is difficult to treat. The differential includes focal acral hyperkeratosis and acrokeratoelastoidosis.

Long-term external radiation exposure of inhabitants in the western Bryansk region of Russia as a consequence of the Chernobyl accident.

The western Bryansk region in south-western Russia was highly contaminated with 137Cs and 134Cs due to the Chernobyl accident in 1986. In 1990, a joint Nordic-Russian project was initiated in order to make measurements and estimates of the absorbed doses to selected groups of inhabitants in this area. The participating individuals were living in small villages with contamination levels between 0.9 and 2.7 MBq m(-2). Only some villages had been decontaminated. Both school-children and adults participated in the study and the number of persons was between 100 and 130 each year, residing in 5 villages. Every year in September-October, from 1990 to 1998. we performed individual measurements of external absorbed doses, assessed with thermoluminescent (TL) dosemeters (LiF). The mean effective dose per year from external irradiation due to the Chernobyl accident of the inhabitants in the villages ranged between 0.8 and 2.9 mSv during the study period and decreased with an apparent half-time of 3.7-8.2 years, depending on village and group. The highest individual doses within one village were, on average higher by a factor of 3 than the mean value for that village. Under the conservative assumption of a decrease rate in the external effective dose of 2% per year after 1998, individuals in the most highly exposed village are assumed to receive a life-time effective dose of about 75 mSv (between 1986 and 2056) from external exposure to caesium radionuclides. The mean value for the villages under study was estimated to be around 65 mSv using the assumed rate of decrease.