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1.
Environ Geochem Health ; 46(8): 270, 2024 Jul 02.
Artículo en Inglés | MEDLINE | ID: mdl-38954122

RESUMEN

Radioactive nuclides cesium (Cs) and strontium (Sr) possess long half-lives, with 135Cs at approximately 2.3 million years and 87Sr at about 49 billion years. Their persistent accumulation can result in long-lasting radioactive contamination of soil ecosystems. This study employed geo-accumulation index (Igeo), pollution load index (PLI), potential ecological risk index (PEPI), health risk assessment model (HRA), and Monte Carlo simulation to evaluate the pollution and health risks of Cs and Sr in the surface soil of different functional areas in a typical mining city in China. Positive matrix factorization (PMF) model was used to elucidate the potential sources of Cs and Sr and the respective contribution rates of natural and anthropogenic sources. The findings indicate that soils in the mining area exhibited significantly higher levels of Cs and Sr pollution compared to smelting factory area, agricultural area, and urban residential area. Strontium did not pose a potential ecological risk in any studied functional area. The non-carcinogenic health risk of Sr to the human body in the study area was relatively low. Because of the lack of parameters for Cs, the potential ecological and human health risks of Cs was not calculated. The primary source of Cs in the soil was identified as the parent material from which the soil developed, while Sr mainly originated from associated contamination caused by mining activities. This research provides data for the control of Cs and Sr pollution in the surface soil of mining city.


Asunto(s)
Radioisótopos de Cesio , Minería , Contaminantes Radiactivos del Suelo , Medición de Riesgo , China , Contaminantes Radiactivos del Suelo/análisis , Radioisótopos de Cesio/análisis , Humanos , Radioisótopos de Estroncio/análisis , Cesio/análisis , Ciudades , Suelo/química , Método de Montecarlo , Monitoreo de Radiación
2.
Radiat Environ Biophys ; 62(1): 143-150, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36436118

RESUMEN

Otoliths are organs used by fish for hearing and keeping balance. They consist of biogenic crystals of hydroxyapatite and do not contain any living cells. Upon exposure to ionizing radiation, otolith hydroxyapatite accumulates radiation-induced stable CO2- radicals whose amount is proportional to absorbed dose. In electron paramagnetic resonance (EPR) dosimetry, carbonate ions are registered and, hence, the total accumulated dose in the fish otolith can be quantified. Therefore, otoliths can be used as individual fish dosimeters to support radiobiological and radioecological studies. An important aspect of otolith-based EPR dosimetry on fish from contaminated water bodies is the potential presence of bone-seeking 90Sr. Consequently, cumulative absorbed doses measured with EPR in otoliths may reflect the superposition of internal exposure to 90Sr/90Y and external exposure due to radionuclides circulating in soft tissue of the fish as well as due to environmental contamination. The objective of the present study was to develop a method that allows for an assessment of the contribution of 90Sr to the total dose in otolith. The method has been tested using otoliths from seven fish taken from reservoirs located in the Southern Urals contaminated with radionuclides including 90Sr. It has been shown that dose to otoliths is largely determined by 90Sr in the hydroxyapatite. The internal dose component can be calculated using activity concentration-to-dose conversion factors, which vary slightly in the range of 2.0-2.8 × 10-3 Gy year-1 per Bq g-1 depending on fish species and age. Internal doses to fish from water bodies with different levels of 90Sr contamination were calculated in the range from 2 mGy to ~ 200 Gy. External dose contribution was derived for two fish only to be about 100 and 40 Gy. It is concluded that EPR dosimetry on fish otoliths is a promising tool when external exposure prevails or is comparable to internal exposure due to 90Sr.


Asunto(s)
Membrana Otolítica , Dosímetros de Radiación , Animales , Radioisótopos de Estroncio/análisis , Hidroxiapatitas/análisis , Agua
3.
J Craniofac Surg ; 34(6): e556-e558, 2023 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-37259191

RESUMEN

Post-acne keloids have become a serious problem affecting the physical and mental health of adolescents. However, traditional single-treatment methods have a high recurrence rate and are highly susceptible to a variety of complications. Postoperative radiotherapy has rapidly become a popular choice for comprehensive postoperative treatment because of its painlessness, non-invasiveness, convenience, low recurrence rate, and few complications. 1 In the available literature, no serious complications have been reported. Here we introduce a case of keloid after acne with isotope strontium-90 as a comprehensive treatment regimen, which leads to extensive depigmentation in the maxillofacial region. Combined with knowledge of the relevant literature, the mechanisms, types, and timing and dose, and reflect on balancing of recurrence rates and complications to deepen our understanding of the disease.


Asunto(s)
Acné Vulgar , Queloide , Adolescente , Humanos , Queloide/cirugía , Radioisótopos de Estroncio , Periodo Posoperatorio , Recurrencia , Resultado del Tratamiento
4.
Environ Monit Assess ; 195(6): 703, 2023 May 22.
Artículo en Inglés | MEDLINE | ID: mdl-37212912

RESUMEN

The habitation and environment are affected by the stable isotopes of caesium (Cs) and strontium (Sr), as well as by their radioactive isotopes. The current work gives insight on Alstonia scholaris' capacity to phytoextract stable caesium (Cs) and strontium (Sr), as well as the plant's ability to protect against the toxicity of both elements. Experiments with Cs [0-5 mM (CsCl)] and Sr [0-3 mM (SrCl2. 6H2O)] dosing in controlled light, temperature, and humidity condition in greenhouse for 21 days were undertaken. Cs and Sr accumulation in different plant parts was quantified with atomic absorption spectroscopy (AAS) and inductively coupled plasma-optical emission spectrometry (ICP-OES) respectively. Hyper-accumulation capacity for Cs and Sr was estimated with indices like transfer factor (TF) and translocation factors (TrF). The uptake pattern of caesium in Alstonia scholaris is 5452.8-24,771.4 mg/kg DW (TF = 85.2-57.6) and in the case of Sr is 1307.4-8705.7 mg/kg DW (TF = 85.3-1.46). The findings demonstrated the plant's ability to transfer Cs and Sr to aboveground biomass on the basis of dry weight, with the majority of the metals being deposited in the shoot rather than the root portion of the plant. For Cs and Sr, with increasing concentration, the plants exhibited the enzymatic expression for defence against metal toxicity by free radicals compared to control. Field emission electron microscopy with energy-dispersive spectroscopy (FESEM with EDS) was employed to assess the spatial distribution of Cs and Sr in plant leaf, indicating the accumulation of Cs, Sr, and their homologous components.


Asunto(s)
Alstonia , Estroncio , Estroncio/toxicidad , Alstonia/metabolismo , Hidroponía , Monitoreo del Ambiente , Cesio/metabolismo , Radioisótopos de Estroncio
5.
Radiat Environ Biophys ; 61(3): 445-464, 2022 08.
Artículo en Inglés | MEDLINE | ID: mdl-35767189

RESUMEN

This study considers the exposure of the population of the most contaminated Gomel and Mogilev Oblasts in Belarus to prolonged sources of irradiation resulting from the Chernobyl accident. Dose reconstruction methods were developed and applied in this study to estimate the red bone-marrow doses (RBMs) from (i) external irradiation from gamma-emitting radionuclides deposited on the ground and (ii) 134Cs, 137Cs and 90Sr ingestion with locally produced foodstuffs. The mean population-weighted RBM doses accumulated during 35 years after the Chernobyl accident were 12 and 5.7 mGy for adult residents in Gomel and Mogilev Oblasts, respectively, while doses for youngest age groups were 20-40% lower. The highest mean area-specific RBM doses for adults accumulated in 1986-2021 were 63, 56 and 46 mGy in Narovlya, Vetka and Korma raions in Gomel Oblast, respectively. For most areas, external irradiation was the predominant pathway of exposure (60-70% from the total dose), except for areas with an extremely high aggregated 137Cs soil to cow's milk transfer coefficient (≥ 5.0 Bq L-1 per kBq m-2), where the contribution of 134Cs and 137Cs ingestion to the total RBM dose was more than 70%. The contribution of 90Sr intake to the total RBM dose did not exceed 4% for adults and 10% for newborns in most raion in Gomel and Mogilev Oblasts. The validity of the doses estimated in this study was assessed by comparison with doses obtained from measurements by thermoluminescence dosimeters and whole-body counters done in 1987-2015. The methodology developed in this study can be used to calculate doses to target organs other than RBM such as thyroid and breast doses. The age-dependent and population-weighted doses estimated in this study are useful for ecological epidemiological studies, for projection of radiation risk, and for justification of analytical epidemiological studies in populations exposed to Chernobyl fallout.


Asunto(s)
Accidente Nuclear de Chernóbil , Animales , Bovinos , Radioisótopos de Cesio , Ingestión de Alimentos , Femenino , Dosis de Radiación , República de Belarús , Radioisótopos de Estroncio
6.
J Environ Manage ; 308: 114620, 2022 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-35149404

RESUMEN

The remediation of contaminated land using plants, bacteria and fungi has been widely examined, especially in laboratory or greenhouse systems where conditions are precisely controlled. However, in real systems at the field scale conditions are much more variable and often produce different outcomes, which must be fully examined if 'gentle remediation options', or GROs, are to be more widely implemented, and their associated benefits (beyond risk-management) realized. These secondary benefits can be significant if GROs are applied correctly, and can include significant biodiversity enhancements. Here, we assess recent developments in the field-scale application of GROs for the remediation of two model contaminants for nuclear site remediation (90Sr and 137Cs), their risk management efficiency, directions for future application and research, and barriers to their further implementation at scale. We also discuss how wider benefits, such as biodiversity enhancements, water filtration etc. can be maximized at the field-scale by intelligent application of these approaches.


Asunto(s)
Restauración y Remediación Ambiental , Contaminantes del Suelo , Biodegradación Ambiental , Radioisótopos de Cesio , Plantas , Gestión de Riesgos , Radioisótopos de Estroncio
7.
Molecules ; 27(12)2022 Jun 09.
Artículo en Inglés | MEDLINE | ID: mdl-35744856

RESUMEN

Strontium-90 (90Sr) is one of the most hazardous radionuclides, and it contributes to radiation exposure by ingestion. The routine determination of 90Sr in marine biological samples is highly desirable given the development of the nuclear power industry. A fast, simple, and low-detection-limit method was developed for the measurement of 90Sr in marine biological samples based on determining 90Y by means of coprecipitation and solvent extraction with bis-2-ethylhexyl-phosphoric acid (HDEHP) in n-heptane. The interfering 210Bi is removed using Bi2S3 precipitation. The separation and purification of eight samples per day can be accomplished through this method. The detection limit of 90Sr for this method is 0.10 Bq/kg (ash weight). The radiochemical procedure was validated by fitting the decay curve of the sample source and by the determination of 90Sr standards.


Asunto(s)
Exposición a la Radiación , Radioisótopos de Estroncio , Radioisótopos , Radioisótopos de Estroncio/análisis
8.
Molecules ; 27(6)2022 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-35335276

RESUMEN

Artificial long-lived radionuclides such as 90Sr and 239,240Pu have been long released into the environment by human nuclear activities, which have a profound impact on the ecological environment. It is of great significance to monitor the concentration of these radionuclides for environmental safety. This paper summarizes and critically discusses the separation and measurement methods for ultra-trace determination of 90Sr, 239Pu, and 240Pu in the environment. After selecting the measurement method, it is necessary to consider the decontamination of the interference from matrix elements and the key elements, and this involves the choice of the separation method. Measurement methods include both radiometric methods and non-radiometric methods. Radiometric methods, including alpha spectroscopy, liquid scintillation spectrometry, etc., are commonly used methods for measuring 239+240Pu and 90Sr. Mass spectrometry, as the representative of non-radiometric measurement methods, has been regarded as the most promising analytical method due to its high absolute sensitivity, low detection limit, and relatively short sample-analysis time. Through the comparison of various measurement methods, the future development trend of radionuclide measurement is prospected in this review. The fully automatic and rapid analysis method is a highlight. The new mass spectrometer with ultra-high sensitivity shows strong analytical capabilities for extremely low concentrations of 90Sr, 239Pu, and 240Pu, and it is expected to develop determination methods with higher sensitivity and lower detection limit.


Asunto(s)
Plutonio , Contaminantes Radiactivos del Suelo , Humanos , Radioisótopos/análisis , Contaminantes Radiactivos del Suelo/análisis , Radioisótopos de Estroncio/análisis
9.
Molecules ; 28(1)2022 Dec 22.
Artículo en Inglés | MEDLINE | ID: mdl-36615288

RESUMEN

In the context of the rapid development of the world's nuclear power industry, it is vital to establish reliable and efficient radioanalytical methods to support sound environment and food radioactivity monitoring programs and a cost-effective waste management strategy. As one of the most import fission products generated during human nuclear activities, 90Sr has been widely determined based on different analytical techniques for routine radioactivity monitoring, emergency preparedness and radioactive waste management. Herein, we summarize and critically review analytical methods developed over the last few decades for the determination of 90Sr in environmental and biological samples. Approaches applied in different steps of the analysis including sample preparation, chemical separation and detection are systematically discussed. The recent development of modern materials for 90Sr concentration and advanced instruments for rapid 90Sr measurement are also addressed.


Asunto(s)
Residuos Radiactivos , Administración de Residuos , Humanos , Radioisótopos de Estroncio/análisis , Residuos Radiactivos/análisis , Fuentes Generadoras de Energía
10.
Wiad Lek ; 75(11 pt 1): 2604-2608, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36591740

RESUMEN

OBJECTIVE: The aim: Research of personal hygiene products with detoxification properties by evaluating their formulation composition, emulsifying and complexing ability to heavy metal ions and radionuclides. PATIENTS AND METHODS: Materials and methods: The complex-forming ability of raw materials with heavy metal ions was determined in vitro, the content of heavy metals was determined by the method of atomic emission spectrometry with inductively coupled plasma (BS EN 13805:2014); determined the content of 137Cs, 232Th, 40K, 226Ra, 90Sr in washings from the surface of the skin of hands treated with personal hygiene products. The means were tested for compliance with the standard on scintillation spectrometers of gamma radiation energy «SEG-001¼ «AKP-S¼ and beta radiation (SEB-01-70); methods used: MI 12-04-099 and MI 12-05-099. RESULTS: Results: A high complexing ability of the pectin-containing «Liana¼ shampoo was found in relation to heavy metal ions (Co2+, Cu2+, Zn2+, Cd2+, Pb2+), as well as in their combined presence. It was established that the effectiveness of removing fatty impurities from the surface of the skin of the «Liana¼ product was 10.1 times higher than that of liquid soap (p<0.001). A high level of deactivating, degassing and antibacterialproperties of the personal care products «Bastion¼ and «Bastion-M¼ was revealed. CONCLUSION: Conclusions: Today, there is significant potential in the creation of formulations for special (sanitary) skin and hair surface treatment, containing natural complexing agents as detoxicants, and can be used in special professional activities associated with the risk of exposure to CBRN factors.


Asunto(s)
Metales Pesados , Radio (Elemento) , Humanos , Radioisótopos de Cesio , Radioisótopos de Estroncio/análisis , Radio (Elemento)/análisis , Torio/análisis , Metales Pesados/análisis , Metales Pesados/química , Higiene
11.
Radiat Environ Biophys ; 60(2): 257-265, 2021 05.
Artículo en Inglés | MEDLINE | ID: mdl-33864119

RESUMEN

The present paper proposes a novel method, based on Bayesian statistics, as a new approach in the field of thermoluminescence dosimetry for the assessment of personal doses in mixed beta-gamma radiation fields. The method can be utilized in situations when the classical way of dose calculation is insufficient or impossible. The proposed method uses a prior function which can be assigned to the unknown parameter and the likelihood function obtained from an experiment, which together can be transformed into the posterior probability distribution of the sought parameter. Finally, the distribution is converted to the value of the dose. The proposed method is supported by analytical and Monte Carlo calculations, which confirmed the results obtained through the Bayesian approach.


Asunto(s)
Dosimetría Termoluminiscente/métodos , Teorema de Bayes , Partículas beta , Radioisótopos de Cesio , Rayos gamma , Humanos , Método de Montecarlo , Radioisótopos de Estroncio
12.
Proc Natl Acad Sci U S A ; 115(14): 3605-3610, 2018 04 03.
Artículo en Inglés | MEDLINE | ID: mdl-29555750

RESUMEN

This study uses a multiisotope (carbon, nitrogen, oxygen, and strontium) approach to examine early animal management in the Maya region. An analysis of faunal specimens across almost 2,000 years (1000 BC to AD 950) at the site of Ceibal, Guatemala, reveals the earliest evidence for live-traded dogs and possible captive-reared taxa in the Americas. These animals may have been procured for ceremonial functions based on their location in the monumental site core, suggesting that animal management and trade began in the Maya area to promote special events, activities that were critical in the development of state society. Isotopic evidence for animal captivity at Ceibal reveals that animal management played a greater role in Maya communities than previously believed.


Asunto(s)
Crianza de Animales Domésticos , Arqueología/historia , Radioisótopos de Carbono/análisis , Ganado/fisiología , Mercadotecnía , Radioisótopos de Nitrógeno/análisis , Radioisótopos de Oxígeno/análisis , Animales , Perros , Guatemala , Historia Antigua , Humanos , Radioisótopos de Estroncio/análisis
13.
Sensors (Basel) ; 21(3)2021 Feb 02.
Artículo en Inglés | MEDLINE | ID: mdl-33540506

RESUMEN

BACKGROUND: It is known that pterygia above a certain size cause astigmatism and other aberrations of the human cornea and thus impair the quality of vision. Exclusive Sr-/Ytt-90 beta irradiation is a highly effective treatment for primary pterygia. The aim of this retrospective study is to determine the extent to which higher order corneal aberrations are affected by this treatment. METHODS: Evaluation of corneal topographies and wavefront aberration data of 20 primary pterygia patients generated before and at different points in time in the first year after irradiation. Additionally, the size of the pterygium was measured. RESULTS: The study showed a significant increase in coma and triple leaf aberrations in pterygia with a horizontal length of 2 mm and more. It was also found that a pterygium size greater than 2 mm significantly induces astigmatism. Both phenomena reduce visual quality. In none of the patients could a pterygium recurrence be detected after irradiation. CONCLUSIONS: If the pterygium size is less than 2 mm, early exclusive Sr/Ytt-90 beta irradiation can be recommended. If the size is more than 2 mm, a pterygium excision 6 months after beta irradiation can be discussed.


Asunto(s)
Córnea , Pterigion , Radioisótopos de Estroncio , Adulto , Anciano , Técnicas Biosensibles , Femenino , Humanos , Masculino , Persona de Mediana Edad , Pterigion/radioterapia , Estudios Retrospectivos , Radioisótopos de Itrio
14.
J Radiol Prot ; 41(3)2021 Aug 24.
Artículo en Inglés | MEDLINE | ID: mdl-34426563

RESUMEN

In compliance with the fundamentals of the government's policy on nuclear and radiation safety, Russia is continuing to implement its national program for decommissioning its nuclear legacy. Under this program, the State Atomic Energy Corporation, 'Rosatom', is carrying out decommissioning and remediation of the Navy's former shore technical bases (STBs) in the Russian Far East. Along with the 'old problems' accumulated during the operation of STBs in the past, new challenges arise because of the planned intensification of radioactive waste (RW) management on the site in the nearest future. The paper presents the results of comprehensive environmental monitoring at the site of temporary storage for spent nuclear fuel (SNF) and RW at Sysoeva Bay, located in Primorsky Krai. One of the site's features is the cross contamination of the environment with radioactive substances and nonradiological pollutants. The dominant radionuclides in the environmental media are137Cs,90Sr, and a minor contribution from60Сo. The soil contamination with artificial radionuclides predominantly relates to the category of industrial waste with local areas classified as very low-level RWs. The contamination penetrated the underground water via migration from the damaged SNF and RW storage facilities. Along with cesium and strontium radionuclides, widespread groundwater pollution with heavy metals (I-III hazardous classes), including Be and As, was revealed. Moreover, the exceedance of permissible levels of Cd reaches 1000 times, and that of radionuclides (90Sr)reaches 50 times. It dictates the necessity to improve the environmental impact assessment by accounting for the nonradiological pollutants in monitoring design. The radiological conditions in the residential area are characterized by the regional background levels. The average annual effective dose of public exposure due to artificial sources does not exceed 40µSv.


Asunto(s)
Monitoreo de Radiación , Residuos Radiactivos , Administración de Residuos , Monitoreo del Ambiente , Residuos Radiactivos/análisis , Federación de Rusia , Radioisótopos de Estroncio
15.
J Radiol Prot ; 41(4)2021 Sep 27.
Artículo en Inglés | MEDLINE | ID: mdl-34134096

RESUMEN

This paper is devoted to the issue of medical care provision to the residents of the Techa riverside settlements affected by long-term radiation exposure. The river was contaminated due to operational and accidental releases of liquid radioactive waste (LRW) by the 'Mayak' Production Association from 1949 to 1956. Contamination of the river and its floodplain with radionuclides, including long-lived90Sr and137Cs, caused long-term external and internal exposure of the population, predominantly of the bone marrow. Protective countermeasures (resettlement of residents, introduction of restrictions on the use of the river and floodplain, construction of wells, etc) did not manage to prevent relatively high exposure doses to the population. The mean dose value of bone marrow exposure in residents of the riverside settlements was 0.35 Gy, whereas the maximum values were up to 7.92 Gy. The first medical examinations by mobile teams of the Moscow Institute of Biophysics were started approximately two years after the onset of LRW releases. Since 1955, exposed residents have been followed up and are undergoing medical treatment at the Clinic of the Urals Research Center for Radiation Medicine of the Federal Medical and Biological Agency (URCRM). This center was established in response to the necessity to study the biological effects of the combined external γ-exposure and exposure due to90Sr in order to arrange medical care for the exposed population. The URCRM Clinic focuses on the provision of hematological care since cases of chronic radiation syndrome were registered among the exposed population in the early period, and increased leukemia incidence has been observed in the long-term period.


Asunto(s)
Exposición a la Radiación , Residuos Radiactivos , Contaminantes Radiactivos del Agua , Residuos Radiactivos/análisis , Ríos , Federación de Rusia/epidemiología , Radioisótopos de Estroncio , Contaminantes Radiactivos del Agua/análisis
16.
Environ Monit Assess ; 193(8): 473, 2021 Jul 06.
Artículo en Inglés | MEDLINE | ID: mdl-34228211

RESUMEN

Radiocaesium and radiostrontium contamination in the 'soil - rhizosphere - plants (aerial parts)' system was monitored in the floodplain ecosystem of the Yenisei River in the near impact zone of the Krasnoyarsk Mining and Chemical Combine (MCC). The monitored system included soil, rhizosphere, and sedge vegetation on islands and the river's east bank. The 137Cs and 90Sr specific activities displayed intricate space and time patterns controlled by the river water level, including the time and duration of floods and their correlation with the sedge vegetation season. The specific activities of both radionuclides, especially 137Cs, were above the background in all years of observation, except in a few cases. The soil-to-plant transfer factor (TF) patterns showed continuous 137Cs and 90Sr influx into the system and annual variations in the shares of their bioavailable and fixed forms, especially for 90Sr. The 90Sr distribution in the 'soil - rhizosphere - plants' system observed in 2014-2016 provides evidence for possible local fallout.


Asunto(s)
Monitoreo de Radiación , Contaminantes Radiactivos del Suelo , Contaminantes Radiactivos del Agua , Radioisótopos de Cesio/análisis , Ecosistema , Monitoreo del Ambiente , Rizosfera , Ríos , Federación de Rusia , Suelo , Contaminantes Radiactivos del Suelo/análisis , Radioisótopos de Estroncio , Contaminantes Radiactivos del Agua/análisis
17.
J Nucl Cardiol ; 27(5): 1728-1738, 2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-32436115

RESUMEN

INTRODUCTION: Strontium-82/Rubidium-82 (82Sr/82Rb) generators are used widely for positron emission tomography (PET) imaging of myocardial perfusion. In this study, the 82Rb isotope yield and production efficiency of two FDA-approved 82Sr/82Rb generators were compared. METHODS: N = 515 sequential daily quality assurance (QA) reports from 9 CardioGen-82® and 9 RUBY-FILL® generators were reviewed over a period of 2 years. A series of test elutions was performed at different flow-rates on the RUBY-FILL® system to determine an empirical correction-factor used to convert CardioGen-82® daily QA values of 82Rb activity (dose-calibrator 'maximum' of 50 mL elution at 50 mL·min-1) to RUBY-FILL® equivalent values (integrated 'total' of 35 mL elution at 20 mL·min-1). The generator yield (82Rb) and production efficiency (82Rb yield/82Sr parent activity) were measured and compared after this conversion to a common scale. RESULTS: At the start of clinical use, the system reported 82Rb activity from daily QA was lower for CardioGen-82® vs RUBY-FILL® (2.3 ± 0.2 vs 3.0 ± 0.2 GBq, P < 0.001) despite having similar 82Sr activity. Dose-calibrator 'maximum' (CardioGen-82®) values were found to under-estimate the integrated 'total' (RUBY-FILL®) activity by ~ 24% at 50 mL·min-1. When these data were used to convert the CardioGen-82 values to a common measurement scale (integrated total activity) the CardioGen-82® efficiency remained slightly lower than the RUBY-FILL® system on average (88 ± 4% vs 95 ± 4%, P < 0.001). The efficiency of 82Rb production improved for both systems over the respective periods of clinical use. CONCLUSIONS: 82Rb generator yield was significantly under-estimated using the CardioGen-82® vs RUBY-FILL® daily QA procedure. When generator yield was expressed as the integrated total activity for both systems, the estimated 82Rb production efficiency of the CardioGen-82® system was ~ 7% lower than RUBY-FILL® over the full period of clinical use.


Asunto(s)
Cardiopatías/diagnóstico por imagen , Imagen de Perfusión Miocárdica/instrumentación , Tomografía de Emisión de Positrones/instrumentación , Generadores de Radionúclidos/instrumentación , Radioisótopos de Rubidio , Radioisótopos de Estroncio , Humanos , Garantía de la Calidad de Atención de Salud , Estudios Retrospectivos
18.
Environ Sci Technol ; 54(23): 15066-15075, 2020 12 01.
Artículo en Inglés | MEDLINE | ID: mdl-33170656

RESUMEN

The Fukushima Dai-ichi Nuclear Power Plants (FDNPPs) accident in 2011 led to an unprecedented release of radionuclides into the environment. Particularly important are 90Sr and 137Cs due to their known health detriments and long half-lives (T1/2 ≈ 30 y) relative to ecological systems. These radionuclides can be combined with the longer-lived 129I (T1/2 = 15.7 My) to trace hydrologic, atmospheric, oceanic, and geochemical processes. This study seeks to evaluate 137Cs, 90Sr, and 129I concentrations in seawater off the coast of Japan, reconcile the sources of contaminated waters, and assess the application of 137Cs/90Sr, 129I/137Cs, and 129I/90Sr as oceanic tracers. We present new data from October 2015 and November 2016 off the coast of Japan, with observed concentrations reaching up to 198 ± 4 Bq·m-3 for 137Cs, 9.1 ± 0.7 Bq·m-3 for 90Sr, and (114 ± 2) × 10-5 Bq·m-3 for 129I. The utilization of activity ratios suggests a variety of sources, including sporadic and independent releases of radiocontaminants. Though overall concentrations are decreasing, concentrations are still elevated compared to pre-accident levels. In addition, Japan's Environment Minister has suggested that stored water from the FDNPPs may be released into the environment and thus continued efforts to understand the fate and distribution of these radionuclides is warranted.


Asunto(s)
Accidente Nuclear de Fukushima , Monitoreo de Radiación , Contaminantes Radiactivos del Agua , Radioisótopos de Cesio/análisis , Radioisótopos de Yodo , Japón , Océanos y Mares , Agua de Mar , Radioisótopos de Estroncio , Contaminantes Radiactivos del Agua/análisis
19.
Support Care Cancer ; 28(7): 3291-3301, 2020 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-31754835

RESUMEN

BACKGROUND: Zoledronic acid (ZA) and strontium-89 have been widely used to treat lung cancer with bone metastases. The authors perform this meta-analysis to better evaluate the clinical outcome of ZA and strontium-89 for non-small cell lung cancer (NSCLC) patients. METHODS: We carried out standard meta-analysis and network meta-analysis based on a comprehensive data retrieval of EMBASE, PubMed, and Cochrane Library databases (up to March 2019). Random and fixed effects models were used where indicated and between-study heterogeneity was assessed. The primary endpoints were overall survival (OS) and skeletal-related events (SREs). The second endpoints were progression-free survival (PFS) and overall response rate (ORR). RESULTS: Seven randomized clinical trials, including 1426 NSCLC patients with seven studies of zoledronic acid and two studies of strontium-89, met the inclusion criteria. Compared with the control group, ZA is associated with a OS benefit (1-year survival rate: RR = 1.76, 95% CI 1.36-2.27; and 24-month survival rate: RR = 2.38, 95% CI 1.35-4.19) and a reduction of SREs (RR = 0.57, 95% CI 0.40-0.84) for the patients with bone metastases. No statistical differences were found in PFS and ORR. Network meta-analysis for the patients with bone metastases showed that ZA + strontium-89 and ZA harbored significantly clinical benefits than strontium-89 and placebo in terms of 1-year survival rate and SREs. Both head-to-head study and network meta-analysis showed that strontium-89 had no statistical impact on OS and SREs compared with placebo. CONCLUSION: Our analysis demonstrates that ZA +strontium-89 can be considered a priority for NSCLC patients with bone metastases, followed by ZA.


Asunto(s)
Conservadores de la Densidad Ósea/uso terapéutico , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Radioisótopos de Estroncio/uso terapéutico , Ácido Zoledrónico/uso terapéutico , Conservadores de la Densidad Ósea/farmacología , Carcinoma de Pulmón de Células no Pequeñas/mortalidad , Humanos , Ensayos Clínicos Controlados Aleatorios como Asunto , Radioisótopos de Estroncio/farmacología , Análisis de Supervivencia , Ácido Zoledrónico/farmacología
20.
Molecules ; 25(6)2020 Mar 21.
Artículo en Inglés | MEDLINE | ID: mdl-32245155

RESUMEN

To reduce uncertainties in determining the source term and evolving condition of spent nuclear fuel is fundamental to the safety assessment. ß-emitting nuclides pose a challenging task for reliable, quantitative determination because both radiometric and mass spectrometric methodologies require prior chemical purification for the removal of interfering activity and isobars, respectively. A method for the determination of 90Sr at trace levels in nuclear spent fuel leachate samples without sophisticated and time-consuming procedures has been established. The analytical approach uses a commercially available automated pre-concentration device (SeaFAST) coupled to an ICP-DRC-MS. The method shows good performances with regard to reproducibility, precision, and LOD reducing the total time of analysis for each sample to 12.5 min. The comparison between the developed method and the classical radiochemical method shows a good agreement when taking into account the associated uncertainties.


Asunto(s)
Espectrometría de Masas/métodos , Residuos Radiactivos/análisis , Espectrofotometría Atómica/métodos , Radioisótopos de Estroncio/análisis , Partículas beta , Modelos Lineales , Espectrometría de Masas/instrumentación , Reproducibilidad de los Resultados , Espectrofotometría Atómica/instrumentación , Radioisótopos de Estroncio/química , Radioisótopos de Estroncio/aislamiento & purificación , Contaminantes Químicos del Agua/análisis , Contaminantes Químicos del Agua/química
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