ABSTRACT
OBJECTIVE: To compare the risk of ovarian malignancy algorithm (ROMA) and Copenhagen Index (CPH-I) in their ability to distinguish epithelial ovarian cancer (EOC) and malignant ovarian tumors (MLOT) from benign ovarian tumors (BeOT) in Japanese women. METHODS: Patients with pathologically diagnosed ovarian tumors were included in this study. The study validated the diagnostic performance of ROMA and CPH-I. RESULTS: Among the 463 Japanese women included in this study, 312 had BeOT, 99 had EOC, and 52 had other MLOT. The receiver-operator characteristic (ROC) area under the curve (AUCs) of ROMA (0.89) and CPH-I (0.89) for distinguishing EOC from BeOT were significantly higher than that of CA125 (0.82) (CA 125 vs. ROMA; p = 0.002, vs. CPH-I; p < 0.001). The ROC-AUCs of ROMA (0.82) and CPH-I (0.81) for distinguishing MLOT from BeOT were significantly higher than that of CA125 (0.75) (CA 125 vs. ROMA: p = 0.003, vs. CPH-I: p < 0.001). The sensitivity (SN)/specificity (SP) of ROMA and CPH-I for distinguishing EOC from BeOT at standard cut-off points were 69%/90%, and 69%/90%, respectively, those for distinguishing MLOT from BeOT were 54%/90%, and 55%/90%, respectively. CONCLUSION: ROMA and CPH-I performed comparably well and better than CA125 in distinguishing EOC from BeOT in Japanese women. ROMA and CHP-I should be used with caution in practical situations, where all histological possibilities for must be considered, because the SNs of ROMA and CPH-I were only 54% and 55%.
Subject(s)
Neoplasms, Glandular and Epithelial , Ovarian Neoplasms , Female , Humans , Algorithms , Biomarkers, Tumor , CA-125 Antigen , Carcinoma, Ovarian Epithelial/diagnosis , East Asian People , Ovarian Neoplasms/pathology , ROC CurveABSTRACT
OBJECTIVE: Transforming the University of Southern California health care system requires that institutions and organizations position equity, diversity, inclusion (EDI), and anti-racism as central to their missions. The purpose of this administrative case report was to describe a systematic approach taken by an academic physical therapy department to develop a comprehensive antiracism plan that engages all interested and affected parties and includes processes for sustainable, long-term engagement. METHODS: Four strategies contributed to organizational change toward anti-racism: Holding Ourselves Accountable; Developing a Plan; Building Consensus; and Providing Education, Support, and Resources. The attitudes of faculty and staff about racism and anti-racist actions were assessed through surveys at the start of the process and after 1 year. Engagement in activities, meetings, and trainings related to EDI and anti-racism was logged for faculty and staff. RESULTS: From November 2020 through November 2021, several outcomes were achieved, including: making structural organizational changes; updating faculty merit review to include EDI; developing a bias reporting mechanism; establishing faculty development activities, resources, and groups; and implementing structured efforts to recruit a diverse cohort. Within that year, faculty and staff engaged in 99.32 hours of EDI and anti-racism trainings, workshops, and resource groups. Survey data showed persistent high support and commitment to EDI and anti-racism. Faculty and staff reported that they felt more equipped to identify and address individual and institutional racism and they reported risking their reputations to talk about race more often. Confidence in their ability to identify and resolve conflicts related to microaggressions, cultural insensitivity, and bias improved. However, their self-reported ability to identify and address structural racism remained unchanged. CONCLUSION: By approaching anti-racism as transformative rather than performative, an academic physical therapy department was able to develop and implement a comprehensive anti-racism plan with high support and engagement. IMPACT: The physical therapy profession has not been immune to racism and health injustice. Organizational change to become anti-racist is imperative for excellence and a necessary challenge to undertake if the physical therapy profession is to transform society and improve the human experience.
Subject(s)
Antiracism , Faculty , Humans , Educational Status , ConsensusABSTRACT
More than a decade has passed since the Fukushima nuclear accident in 2011 and contamination around the nuclear power plant is primarily caused by 137Cs. One of the materials retaining radiocesium in the environment is radiocesium-bearing silicate glass microparticles (CsMPs), which have not been reported in previous nuclear accidents. Although the prediction of environmental fates of CsMPs is of interest because of their extremely high specific radioactivity, knowledge about their physicochemical properties is still limited. Here we show that the dissolution behavior of CsMPs is comparable to that of silica-rich glass and significantly depends on the surrounding environment. CsMP dissolution experiments were conducted in solutions with various solute components and pH levels at 60 °C. In neutral and basic solutions, the estimated dissolution rate was accelerated by alkali ions such as Na+, which is known to play a catalytic role for the dissolution of silica. In contrast, the dissolution in acid was slow even in the presence of alkali ions. The dissolution under acid conditions was possibly retarded by a thin amorphous silica layer formed on the CsMP surfaces. Such characteristics of the dissolution are consistent with that of silica-rich glass. To infer the dissolution behavior of CsMPs in the human body, the dissolution rate in Ringer's solution at 37 °C was estimated as 1.00 ± 0.37 µm/year.
ABSTRACT
Application of organic amendments (OAMs) often enhances arsenic (As) dissolution in paddy soils. Therefore, understanding the properties of OAMs that determine the extent of As dissolution is essential for appropriate soil management. Since As dissolution increases with decrease in soil redox potential caused by microbial respiration, the decomposability of OAMs might be a critical factor controlling As dissolution in amended soils. We hypothesized that contents of acid detergent-soluble organic matter (ADSOM, mainly composed of non-fiber organic matter and hemicellulose) in OAMs can help estimate the potential of OAMs in accelerating As dissolution in soils with added OAMs. Therefore, two contrasting soil types, Andosol and Fluvisol, were mixed with 24 different OAMs and subjected to anaerobic incubation for 14 weeks. Changes in soil Eh and dissolved As contents were monitored throughout the incubation period, and As species in solid phases and ferrous iron (Fe(II)) contents in soils were measured after 2 and 6 weeks of incubation. The higher the ADSOM content in soils with OAMs, the higher the dissolved As contents in soils and the lower the Eh values. Dissolved As also positively correlated with the proportion of As(III) in solid phases and Fe(II) content after 2 and 6 weeks of incubation, indicating that decomposition of ADSOM led to reducing soil conditions, thereby promoting the reduction of As(V) and As-bearing Fe oxides and subsequent As dissolution. The results were consistent between the two types of soils, despite dissolved As content in the Andosol being two orders lower than that in Fluvisol. This is the first study to demonstrate that ADSOM can be a prominent indicator of the potential of OAMs, for promoting As dissolution, when applied to paddy soils.
Subject(s)
Arsenic , Oryza , Soil Pollutants , Arsenic/analysis , Detergents , Anaerobiosis , Soil , Solubility , Oxidation-Reduction , Ferrous Compounds , Soil Pollutants/analysisABSTRACT
Despite the presence of minerals that allow Cs fixation in soils, 137Cs remains available to crops for several years after its deposition, particularly in pasture soils. Larger amounts of organic matter derived from herbage residues are accumulated in pasture soils than in tilled farmland soils. As the above-ground part of herbage crops initially received airborne 137Cs during the accident at Fukushima Daiich nuclear power plant (FDNPP), the organic matter originated from the contaminated herbage should play an important role in the fate of 137Cs in soils. To evaluate the role of organic matter on 137Cs distribution between potentially mobile and immobile fractions, we compared the distribution of 137Cs and stable 133Cs, which are differently associated with organic matter, by sequential extraction and density fractionation. Soil samples were collected 8 years after the accident from Andosols in pasture fields located about 160 km southwest of FDNPP. More than 90% of 137Cs was not extracted even after oxidative digestion of organic matter, suggesting that most 137Cs was strongly associated with soil minerals. Density fractionation results showed that the 137Cs/133Cs ratio was highest in the density fraction of 1.6-1.8 g cm-3, in which organic matter -including fragmented and decomposed plant detritus -was associated with minerals. Mineral-free organic matter, mostly composed of fresh plant detritus (<1.6 g cm-3), had a higher 137Cs/133Cs ratio than that of crops harvested in the same year of soil sampling. Thus, the transfer of 137Cs from soil to plants decreased with cultivation cycles. Our results demonstrate that plant-available 137Cs in pasture soil decreased with aging time, not only through increased 137Cs fixation in mineral-dominated fractions but also through its physical sequestration in aggregates.
Subject(s)
Fukushima Nuclear Accident , Radiation Monitoring , Soil Pollutants, Radioactive , Cesium Radioisotopes/analysis , Japan , Nuclear Power Plants , Soil , Soil Pollutants, Radioactive/analysisSubject(s)
Cultural Diversity , Health Equity , Minority Groups , Physical Therapy Modalities , Systemic Racism , Humans , United StatesABSTRACT
AIM: The purpose of this study was to investigate whether the Ki67 values were associated with survival for predicting prognosis in patients with advanced ovarian cancer receiving neoadjuvant chemotherapy (NACT). METHODS: Among 17 patients treated with NACT, 13 patients were available for tissue samples from matched pre- and post-therapy tissues. Ki67 scores were transformed to a logarithmic scale for the statistical analyses. The optimal cutoff values of the log-phase Ki67 were assessed by receiver operating characteristic (ROC) analysis. Kaplan-Meier analysis, the log-rank test, and Cox regression analysis were carried out to analyze survival. RESULTS: The Ki67-decrease and post-NACT Ki67 were the independent factors associated with relapse-free survival (RFS) (p < 0.001 and p = 0.003). No association was observed on overall survival. The optimal cutoff values for the Ki67-decrease and the post-NACT Ki67 were 6.67% and 5.46 based on ROC where the area under ROC curves (AUC) were 1.00 (p < 0.001) with the 100% sensitivity and specificity. The median RFS was 537 days in patients showing Ki67-decrease >6.66% or post-NACT Ki67 level <5.46, while it was 224 days in those with Ki67 decrease ≤6.66% or post-NACT Ki67 level ≥5.46 (p = 0.001). CONCLUSIONS: The Ki67-decrease and the lower post-NACT Ki67 are independent factors associated with favorable RFS, indicating that they could be precise biomarker candidates for prognosis in NACT-administered patients with advanced ovarian cancer.
Subject(s)
Neoadjuvant Therapy , Ovarian Neoplasms , Chemotherapy, Adjuvant , Female , Humans , Ki-67 Antigen , Neoplasm Recurrence, Local/pathology , Neoplasm Staging , Ovarian Neoplasms/drug therapy , Ovarian Neoplasms/pathology , Prognosis , Retrospective StudiesABSTRACT
We report a 34-year-old woman with recurrent gestational trophoblastic neoplasia (GTN) who showed hypersensitivity to etoposide. Computed tomography (CT) revealed a 32-mm solid mass in the right lung and a 101-mm cystic mass with solid components in the left side of the liver. The patient's serum human chorionic gonadotropin (HCG) level was 689 439 mIU/mL. After eight cycles of combined paclitaxel 175 mg/m2 on day 1, ifosfamide 1 g/m2 on days 2-5, and cisplatin 20 mg/m2 on days 2-5 (TIP) every 3 weeks, the serum HCG level decreased to 2.4 mIU/mL. CT scan revealed disappearance of the lung tumor and significant reduction in the solid components of the liver tumor. Then, left hemihepatectomy was performed. After 3 months, there was no evidence of the disease, and the serum HCG level normalized. Thus, TIP chemotherapy, followed by residual mass resection, might be effective for methotrexate-resistant GTN.
Subject(s)
Gestational Trophoblastic Disease , Methotrexate , Adult , Antineoplastic Combined Chemotherapy Protocols/adverse effects , Cisplatin/adverse effects , Dactinomycin/therapeutic use , Drug Resistance, Neoplasm , Etoposide/therapeutic use , Female , Gestational Trophoblastic Disease/drug therapy , Humans , Ifosfamide/adverse effects , Methotrexate/adverse effects , Neoplasm Recurrence, Local/drug therapy , Paclitaxel/therapeutic use , Pregnancy , Salvage TherapyABSTRACT
Ethyl(dimethyl)(tetradecyl)ammonium ethyl sulfate, used in laundry detergents, shampoos, and body soaps, is classified by the Japanese Chemical Substances Control Law as a priority assessment chemical substance for environmental effects. However, its toxicity data for human health are insufficient. This study evaluated this chemical under the Safety Examination of Existing Chemicals and Safety Programmes of the Ministry of Health, Labour and Welfare (MHLW). The MHLW conducted bacterial reverse mutation (Ames test), in vitro chromosomal aberration, and combined repeated-dose and reproductive/developmental toxicity screening tests. We performed a screening assessment of ethyl(dimethyl)(tetradecyl)ammonium ethyl sulfate for human health. The chemical showed a negative reaction in the Ames test and a positive reaction in the in vitro chromosomal aberration test with metabolic activation in rats. The combined repeated-dose and reproductive/developmental toxicity screening test showed significantly decreased food consumption at 50 mg/kg body weight/day, but no reproductive and developmental toxicity was observed. The no-observed-effect level of 15 mg/kg/day was obtained as a screening value. Therefore, this chemical was classified as hazard class 3, with a derived-no-effect level of 0.025 mg/kg/day. The results of this study will be useful for risk assessment of groups of structurally similar alkyl quaternary ammonium surfactants.
Subject(s)
Genitalia/drug effects , Quaternary Ammonium Compounds/toxicity , Animals , Cell Line , Cricetinae , Dose-Response Relationship, Drug , Eating , Female , Male , Mutagenicity Tests , No-Observed-Adverse-Effect Level , Organ Size/drug effects , Rats , Rats, Sprague-DawleyABSTRACT
Paddy fields are anaerobic and facilitate arsenite (As(III)) elution from the soil. Paddy-field rice accumulates arsenic (As) in its grains because silicate transporters actively assimilate As(III) during the reproductive stage. Reducing the As level in rice grains is an important challenge for agriculture. Using a forward genetic approach, we isolated a rice (Oryza sativa) mutant, low arsenic line 3 (las3), whose As levels were decreased in aerial tissues, including grains. The low-As phenotype was not observed in young plants before heading (emergence of the panicle). Genetic analyses revealed that a deficiency in alcohol dehydrogenase (ADH) 2 by mutation is responsible for the phenotype. Among the three rice ADH paralogues, ADH2 was the most efficiently produced in root tissue under anaerobic conditions. In wild-type (WT), silicon and As concentrations in aerial tissues increased with growth. However, the increase was suppressed in las3 during the reproductive stage. Accordingly, the gene expression of two silicate transporters, Lsi1 and Lsi2, was increased in WT around the time of heading, whereas the increase was suppressed in las3. These results indicate that the low-As phenotype in las3 is due to silicate transporter suppression. Measurement of intracellular pH by 31P-nuclear magnetic resonance revealed intracellular acidification of las3 roots under hypoxia, suggesting that silicate transporter suppression in las3 might arise from an intracellular pH decrease, which is known to be facilitated by a deficiency in ADH activity under anaerobic conditions. This study provides valuable insight into reducing As levels in rice grains.
Subject(s)
Alcohol Dehydrogenase/genetics , Arsenic/metabolism , Membrane Transport Proteins/metabolism , Oryza/genetics , Plant Proteins/genetics , Silicates/metabolism , Alcohol Dehydrogenase/metabolism , Oryza/enzymology , Oryza/metabolism , Plant Proteins/metabolismABSTRACT
A part of radiocesium emitted during the Fukushima nuclear accident was incorporated in glassy water-resistant microparticles, called Type-A particles, which are spherical with ~ 0.1 to 10 µm diameter and ~ 10-2 to 102 Bq cesium-137 (137Cs) radioactivity; they were emitted from Unit 2 or 3 of the Fukushima Daiichi Nuclear Power Plant. Meanwhile, Type-B particles, having various shapes, 50-400 µm diameter, and 101-104 Bq 137Cs radioactivity, were emitted from Unit 1. The chemical properties of these radioactive particles have been reported in detail, but previous studies investigated only a small number of particles, especially Type-B particles. We tried to understand radioactive particles systematically by analyzing a large number of particles. Micro-X-ray computed tomography combined with X-ray fluorescence analysis revealed the presence of many voids and iron-rich part within Type-B particles. The 137Cs concentration (Bq mm-3) of Type-A particles was ~ 10,000 times higher than that of Type-B particles. Among the Type-B particles, the spherical ones had higher concentration of volatile elements than the non-spherical ones. These differences suggested that Type-A particles were formed through gas condensation, whereas Type-B particles were formed through melt solidification. These findings might contribute to the safe decommissioning of reactors and environmental impact assessment.
ABSTRACT
BACKGROUND: Frailty is broadly characterized by vulnerability and decline in physical, mental and social activities and is more common in elderly patients with type 2 diabetes mellitus (T2DM). Frailty is closely associated with nutrition, muscle strength, inflammation, and hormones etc. In hormones, dehydroepiandrosterone sulfate (DHEA-S) and cortisol are suggested to be such candidates affecting frailty. Little investigation has been performed using a wider range of measures of frailty to clarify risk factors for frailty including the above two hormones. METHODS: We performed a cross-sectional study to investigate the risk factors for frailty in elderly T2DM patients (n = 148; ≥65 years), using a broad assessment, the clinical frailty scale. We compared parameters between the non-frail and frail groups using the unpaired t and Mann-Whitney U tests. The Jonckheere-Therpstra test was used to identify relationships with the severity of frailty, and risk factors were identified using binary regression analysis. RESULTS: Simple regression analysis identified a number of significant risk factors for frailty, including DHEAS < 70 µg/dL and cortisol/DHEA-S ratio ≥ 0.2. Multiple regression analysis showed that low albumin (< 4.0 g/dl) (odds ratio [OR] = 5.79, p < 0.001), low aspartate aminotransferase (AST) activity (< 25 IU/L) (OR = 4.34, p = 0.009), and low body mass (BM) (< 53 kg) (OR = 3.85, p = 0.012) were independent risk factors for frailty. A significant decrease in DHEA-S and a significant increase in the cortisol/DHEA-S ratio occurred alongside increases in the severity of frailty. DHEA-S concentration positively correlated with both serum albumin and BM. CONCLUSIONS: Hypoalbuminemia, low AST, and low BM are independent risk factors for frailty in elderly T2DM patients, strongly implying relative malnutrition in these frail patients. DHEA-S may be important for the maintenance of liver function and BM. A decrease in DHEA-S and an increase in the cortisol/DHEAS ratio may be involved in the mechanism of the effect of malnutrition in elderly T2DM patients.
Subject(s)
Diabetes Mellitus, Type 2 , Frailty , Aged , Aspartate Aminotransferases , Cross-Sectional Studies , Dehydroepiandrosterone Sulfate , Diabetes Mellitus, Type 2/diagnosis , Diabetes Mellitus, Type 2/epidemiology , Frailty/diagnosis , Frailty/epidemiology , Humans , Risk Factors , Serum AlbuminABSTRACT
The mobility of 137Cs in soil decreases with time owing to fixation by micaceous minerals. Such ageing is a critical parameter for estimating and predicting annual change in 137Cs contamination risk of agricultural products. The decrease in the exchangeable fraction of 137Cs has traditionally been used as an index of the 137Cs ageing. Under field conditions, however, exchangeable 137Cs is influenced by several environmental factors. In this study, we propose a new index to evaluate the 137Cs ageing with minimum influence of environmental factors. The ratio of the exchangeable 137Cs fraction to exchangeable fraction of 133Cs ((137Cs/133Cs)exch) eliminates the influence of environmental factors on exchangeable 137Cs. We assessed the applicability of the (137Cs/133Cs)exch index, using a four-year field study of a rice paddy in allophanic Andosol, starting 200 days after the Fukushima Dai-ichi Nuclear Power Plant accident. The influence of K fertilization was also investigated. The 137Cs and 133Cs exchangeable fractions varied together, indicating that both were similarly controlled by environmental factors. The values of (137Cs/133Cs)exch decreased with time, reflecting 137Cs fixation by the ageing. The half-time of the (137Cs/133Cs)exch decline was 6.6-17.7 years. Relative to K fertilization, the lack of K fertilization seemed to affect the 137Cs ageing in two ways: the early 137Cs fixation progressed more rapidly, probably because fewer competing K+ ions were present, and the long-term ageing process was occasionally hampered, probably by the release of reserve K from micaceous minerals. The (137Cs/133Cs)exch values were similar to the ratio of the 137Cs to 133Cs transfer factor of the rice straw. Thus, we conclude that the (137Cs/133Cs)exch index is reliable for evaluating the 137Cs ageing, decrease in 137Cs mobility caused by the diffusion into micaceous mineral interlayer, in the field.
Subject(s)
Cesium Radioisotopes/analysis , Fukushima Nuclear Accident , Radiation Monitoring , Soil Pollutants, Radioactive , Fertilizers , Ions , Japan , Minerals , PotassiumABSTRACT
Spherical radioactive caesium (Cs)-bearing microparticles (CsMPs) were emitted during the Fukushima Dai-ichi Nuclear Power Plant (FDNPP) accident in March, 2011. The emission source (timing) and formation process of these particles remain unclear. In this study, the isotopic ratios of uranium (235U and 238U) and caesium (133Cs, 134Cs, 135Cs, and 137Cs) isotopes in the five spherical CsMPs (ca. 2 µm in size) sampled at 50 km west of the FDNPP were determined using secondary ion mass spectrometry and laser ablation-ICPMS, respectively. Results showed that the 235U/238U ratios of CsMPs were homogeneous (1.93 ± 0.03, N = 4) and close to those estimated for the fuel cores in units 2 and 3, and that the Cs isotopic ratios of CsMP were identical to those of units 2 and 3. These results indicated that U and Cs in the spherical CsMPs originated exclusively from the fuel melt in the reactors. Based on a thorough review of literatures related to the detailed atmospheric releases of radionuclides, the flow of plumes from the FDNPP reactor units during the accident and the U and Cs isotopic ratio results in this study, we hereby suggest that the spherical CsMPs originate only from the fuel in unit 2 on the night of 14 March to the morning of 15 March. The variation range of the analysed 235U/238U isotopic ratios for the four spherical particles was extremely narrow. Thus, U may have been homogenised in the source through the formation of fuel melt, which ultimately evaporating and taken into CsMPs in the reactor and was released from the unit 2.
ABSTRACT
Radiocaesium-bearing microparticles (CsMPs), which are substantially silicate glass, were formed inside the damaged reactor and released to the environment by the Fukushima Dai-ichi Nuclear Power Plant accident in March 2011. The present study reports several valuable findings regarding their composition and structure using advanced microanalytical techniques. X-ray absorption near-edge structure of Fe L3-absorption indicated that the oxidation state of the iron dissolved in the glass matrix of the CsMPs was originally nearly divalent, suggesting that the atmosphere in which the CsMPs were formed during the accident was considerably reductive. Another major finding is that sodium, which has not been recognised as a constituent element of CsMPs thus far, is among the major elements in the glass matrix. The atomic percent of Na is higher than that of other alkali elements such as K and Cs. Furthermore, halite (NaCl) was found as an inclusion inside a CsMP. The existence of Na in CsMPs infers that seawater injected for cooling might reach the inside of the reactor before or during the formation of the CsMPs. These results are valuable to infer the environment inside the reactor during the accident and the debris materials to be removed during the decommissioning processes.
Subject(s)
Air Pollutants, Radioactive/analysis , Cesium Radioisotopes/analysis , Fukushima Nuclear Accident , Particulate Matter/analysis , Air Pollutants, Radioactive/chemistry , Cesium Radioisotopes/chemistry , Humans , Iron/chemistry , Oxidation-Reduction , Particulate Matter/chemistry , Sodium , Spectrum AnalysisABSTRACT
Accumulating evidence has indicated that microRNAs play a critical role in the pathogenesis of human cancers. microRNA-34a (miR-34a) has been shown to be a key regulator of tumor suppression by targeting several cancer-related signals, including the interleukin-6 receptor (IL-6R)/Signal Transducers and Activator of Transcription 3 (STAT3) signaling pathway. Previously, we determined that miR-34a expression was frequently reduced in high-grade serous carcinoma (HGSC), the major subtype of epithelial ovarian cancer (EOC). Considering that the IL-6R/STAT3 signaling pathway is upregulated and believed to be a potential therapeutic target in EOC, we investigated the biological significance of reduced miR-34a expression in HGSC with regard to IL-6R signaling. Additionally, we evaluated the viability of miR-34a as a therapeutic application for HGSC both in vitro and in vivo. Accordingly, we found that the ectopic expression of miR-34a significantly reduced tumor proliferation and invasion through downregulation of IL-6R expression, suggesting that reduced miR-34a expression might play an important role in the malignant potential of HGSC through upregulation of the IL-6R/STAT3 signaling pathway. Moreover, we demonstrated that replacement of miR-34a reduced tumorigenicity of HGSC in vivo. Therefore, this study may provide the rationale for miR-34a replacement as a promising therapeutic strategy for HGSC.
ABSTRACT
Scientists face challenge in identifying the radioactive materials which are found as dotted images on various imaging plate (IP) autoradiographic photos of radioactively contaminated materials by the Fukushima Dai-ichi Nuclear Power Plant (F1NPP, or FDNPP) accident, such as air filter, fugitive dust, surface soil, agricultural materials, and water-shed samples. It has been revealed that they are minute particles with distinct morphology and elemental composition with high specific radioactivity, and different from those of the so-called Chernobyl hot particles. Basically, they are glassy particles once molten, composed of Si, O, Fe, Zn etc. with highly concentrated radiocaesium, which can be called as radiocaesium-bearing microparticles (CsMP). At present, CsMP can be classified into two types, Types-A and -B, which are characterized by different specific radioactivity, 134Cs/137Cs ratio, size and morphology, and geographic distribution around F1NPP. Such studies on the CsMP from various aspects have provided valuable information about what happened in the nuclear reactors during the F1NPP accident and fates of the CsMP in the environment. This review first provides a retrospective view on the research history of the CsMP, which is helpful to understand the unique character of the CsMP. Subsequently, more details about the current understanding of the natures of these hot particles, such as origin, morphology, chemical compositions, thermal properties, water-solubility, and secondary migration of CsMP in river and ocean systems are described with future prospects.
Subject(s)
Cesium Radioisotopes/analysis , Radiation Monitoring , Radioactive Fallout/analysis , Soil Pollutants, Radioactive/analysis , Water Pollutants, Radioactive/analysis , Fukushima Nuclear Accident , Japan , Nuclear Power PlantsABSTRACT
CONTEXT: Elderly patients with type 2 diabetes mellitus (T2DM) have a high prevalence of frailty and/or sarcopenia. Sarcopenia is thought to be related to discordant secretions of the adrenal hormones cortisol and dehydroepiandrosterone (DHEA), as well as the sulfate ester of DHEA (DHEA-S). The current study sought to evaluate the risk factors for sarcopenia in elderly patients with T2DM. DESIGN AND PATIENTS: We enrolled 108 consecutive elderly patients aged ≥65 years with T2DM (mean age, 76.2 ± 7.3 years; 43.5% males). Sarcopenia was assessed and diagnosed based on the Asian version of the diagnostic criteria regarding muscular strength, physical function, and muscle mass. We assessed various physical parameters, blood tests, and atherosclerosis markers and statistically determined the risk factors for sarcopenia. RESULTS: Multiple regression analysis showed that the independent risk factors for sarcopenia were a serum cortisol/DHEA-S ratio ≥0.2, diastolic blood pressure <70 mm Hg, Hb concentration <13 g/dL, and an ankle brachial index <1.0. The strongest risk factor for sarcopenia was a serum cortisol/DHEA-S ratio ≥0.2. An increase in the serum cortisol/DHEA-S ratio reflected higher cortisol values and lower DHEA-S values in patients with sarcopenia compared with those in nonsarcopenic patients. The concentrations of cortisol and DHEA-S, as well as the cortisol/DHEA-S ratio, changed in accordance with the severity of sarcopenia. CONCLUSIONS: A relative increase in cortisol may reflect the presence of stress and stimulate muscle catabolism, whereas a relative decrease in DHEA-S may cause a decrease in the anabolic action of DHEA on muscle; the combination of these factors may lead to sarcopenia.
ABSTRACT
Radiocaesium-bearing microparticles (CsMPs) composed of silicate glass were released by the Fukushima Daiichi Nuclear Power Plant accident in March 2011. Since CsMPs contain a high concentration of radiocaesium, their dynamics and fate in the environment are urgent issues to be investigated. Here, we show that CsMPs are dissolved by weathering in the environment and that their radioactivity is more rapidly decreased by dissolution than the physical decay of radiocaesium. We conducted dissolution experiments with CsMPs in pure water that absorbed CO2 from the atmosphere and in artificial seawater at several temperatures. The dissolution progress was monitored by the decrease in the 137Cs radioactivity in CsMPs, and the dissolution rate was estimated. The activation energy for the dissolution of CsMPs was estimated to be 65 and 88 kJ/mol and the dissolution rate at 13 °C (approximate annual mean temperature in Fukushima City) was 0.014 and 0.140 µm/y for pure water and seawater, respectively, assuming that radiocaesium is uniformly distributed in spherical CsMPs. The shapes of the CsMPs dissolved in pure water were considerably altered, suggesting that the dissolution proceeded without maintaining the geometry. Tin oxide and iron oxide nanoparticulates formed on the surfaces. Such features were similar to those observed in CsMPs recently collected in Fukushima Prefecture, indicating that weathering dissolution of CsMPs is also occurring in the environment. For the CsMPs dissolved in seawater, a crust of secondary Mg- and Fe-rich minerals was formed, and the glass matrix inside the crust decreased, creating space between the crust and the glass matrix.
ABSTRACT
Soil amendments with zeolite and vermiculite were expected to prevent radiocaesium (137Cs) dissolution and uptake from the soil by plants. In this study, we investigated how zeolite and vermiculite added to soil influence the radiocaesium fixation with ageing. Zeolite and vermiculite were mixed with soil (1â¯wt%) before or after the addition of carrier-free caesium-137 (137Cs) to soils with different radiocaesium interception potential (RIP), which is related to the capacity of the soil to fix trace radiocaesium. Then, the soils were exposed for repeated wet and dry cycles to accelerate 137Cs immobilization, and its extractability by 1â¯molâ¯L-1 ammonium acetate was determined before and after 30 dry and wet cycles. Before accelerated ageing (i.e before dry and wet cycles), when 137Cs was adsorbed on the soil before the addition of the amendments, the addition of zeolite and vermiculite caused a decrease in the amount of exchangeable 137Cs in low-RIP soils but an increase in the amount of exchangeable 137Cs in high-RIP soils. The amount of exchangeable 137Cs was significantly decreased after accelerated ageing regardless of the application of amendments. However, radiocaesium fixation with accelerated ageing was partly inhibited by the addition of zeolite, regardless of the RIP values. The 137Cs adsorbed on highly selective sites in zeolite is exchangeable by 1â¯molâ¯L-1 ammonium acetate. Thus, because a portion of the 137Cs is selectively adsorbed on highly selective sites in zeolite, the redistribution of 137Cs to frayed edge site followed by ageing-induced fixation was likely limited. However, when 137Cs was adsorbed on the soil before the addition of the amendments, the addition of zeolite and vermiculite had little influence on the amount of exchangeable 137Cs. In conclusion, the use of realistic doses of zeolite and vermiculite as agricultural amendments is not effective in enhancing the immobilization of radiocaesium in soil.