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Background: Anthropogenic gadolinium (Gd), originating from Gd-based contrast agents (GBCAs) used in magnetic resonance imaging (MRI), is widely identified in the aquatic environment with concerns about toxicity and accumulation. We aimed to present new data on anthropogenic Gd in the Tone River, which has the largest drainage area in Japan, and then to compare the current data with those obtained in 1996. Methods: The water samples were collected on August 9−10, 2020, at 15 different locations of the Tone River in Japan. The concentrations of the rare earth elements (REEs) were measured by inductively coupled plasma-mass spectrometry and normalized to Post-Archean Australian Shale to construct shale-normalized REE patterns. The degree of Gd-anomaly was defined as the percentage of anthropogenic Gd to the geogenic background and used to compare the water samples from different locations. Pearson's correlation coefficients were calculated. Results: All the samples displayed positive Gd anomalies. The Gd-anomaly ranged from 121 to 6,545% and displayed a repeating decrease-and-increase trend. The Gd-anomaly showed strong positive correlations to the number of hospitals (r = 0.88; p < 0.001) and their MRI units (r = 0.89; p < 0.001). Conclusions: Our study revealed notable anomalies of Gd concentrations in river water in Japan, with strong positive correlations to the number of major hospitals and their MRI units. Compared with the previous report in 2000, the Gd-anomaly in Tone River increased from 851% (sampled in 1996) to 6,545%, i.e., 7.7 times, reflecting the increased use of GBCAs in hospitals. Relevance statement: Notable Gd concentration anomalies in river water in Japan were observed. This result underlines the importance of more extensive research on anthropogenic gadolinium, and investigations of risks to human health as well as the development of effective removal technologies may be necessary. Key points: • All water samples from Tone River displayed positive Gd anomalies. • The Gd anomalies increased to 7.7 times higher over the past 24 years. • Correlations between Gd values and the number of hospitals and MRI units were observed. [ABSTRACT FROM AUTHOR]

Conclusions: The presence of endolymphatic hydrops (EH) in the vestibule on magnetic resonance imaging (MRI) might be a high-risk factor for complications in cases that are candidates for stapes surgery. Objective: Pre-operative detection of EH could be valuable in cases that are candidates for stapes surgery to prevent unpredictable complications following surgery. Pre-operative MRI findings and postoperative findings following stapes surgery were compared to evaluate the efficacy of such MRI evaluation for the management of cases with otosclerosis. Subjects and methods: Sixteen cases who underwent pre-operative evaluation by 3T MRI performed 4 h after intravenous injection of gadolinium and stapes surgery for otosclerosis were recruited. Imaging data concerning the degree of EH in the vestibule and cochlea were compared with postoperative clinical findings for all cases. Results: Mild EH in the cochlea or the vestibule was observed in eight ears and one ear, respectively, whereas one ear showed significant EH both in the cochlea and the vestibule. The post-operative course was uneventful in 12 of 14 cases with no EH in the vestibule, and the other two cases had a short period of dizziness, but two cases with EH in the vestibule had a long period of dizziness. [ABSTRACT FROM AUTHOR]

Objectives: This study aimed to assess, among Japanese patients with cardiac sarcoidosis (CS), the implantable cardioverter-defibrillator (ICD) recommendations from the 2017 American Heart Association/American College of Cardiology/Heart Rhythm Society (AHA/ACC/HRS) guidelines for management of patients with ventricular arrhythmias and the prevention of sudden cardiac death (SCD)., Background: Although ICDs are used to prevent SCD from ventricular tachycardia or ventricular fibrillation (VT/VF) in patients with CS, the generalizability of the AHA/ACC/HRS guidelines for Japanese patients with CS remains unclear., Methods: This study examined 188 consecutive patients with CS in 2 tertiary hospitals between 1979 and 2020. Patients were followed for a primary outcome of VT/VF or SCD., Results: During a median follow-up of 5.68 years, the primary outcome occurred in 44 patients (23%). Patients with a Class I recommendation for ICD implantation showed the highest incidence of the primary outcome among patients in whom the guideline recommendations for ICD implantation were used (log-rank test; p = 0.03). However, compared with patients with left ventricular ejection fractions (LVEFs) ≤35%, there was no significant difference in the incidence of the primary outcome among patients with LVEFs >35% and those who required a permanent pacemaker (p = 0.31); similar results were observed in those with LVEFs >35% and late gadolinium enhancement during cardiovascular magnetic resonance imaging (p = 0.22)., Conclusions: The American guideline recommendations for ICD implantation might be applicable to Japanese patients with CS. Implantation of an ICD may need to be considered in these patients if they require a permanent pacemaker or have late gadolinium enhancement, regardless of LVEF., Competing Interests: Funding Support and Author Disclosures Dr. Nagai was supported by a Grant-in-Aid for Young Scientists from the Japan Society for the Promotion of Science (15K19402) and by a grant from the Japan Heart Foundation. The authors have reported that they have no relationships relevant to the contents of this paper to disclose., (Copyright © 2021 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.)

In April 2016, a series of earthquakes (M 7.3 on the Japan Meteorological Agency scale) occurred in Kumamoto, Japan causing serious damage to underground sewerage networks. In this study, we evaluated sewer exfiltration in groundwater in the Kumamoto area after the earthquakes by using multiple tracers. We used 14 pharmaceuticals, including carbamazepine and crotamiton, and anthropogenic Gd as tracers, and we measured concentrations of these tracers from September 2016 to November 2017 seasonally. The detection frequency of caffeine, carbamazepine, crotamiton, ibuprofen, and anthropogenic Gd ranged from 29% to 45%, and the concentrations of the pharmaceuticals in the groundwater were lower than those in previous studies. The median of all pharmaceutical concentrations did not decrease, whereas the median of the sum of crotamiton and carbamazepine concentrations, which are quantitative sewage markers, decreased with time. The sewer exfiltration rates in September 2016 estimated using carbamazepine, crotamiton, and anthropogenic Gd were 0.59 ± 0.27%, 0.66 ± 0.47%, and 0.11 ± 0.18% of sewage dry weather flow, respectively, indicating that the effect of the earthquakes on sewer exfiltration was small, probably because the damaged sewers were quickly repaired. This study demonstrated that a multiple-tracer approach is useful for evaluating sewer exfiltration after major earthquakes., (Copyright © 2021 Elsevier B.V. All rights reserved.)

Purpose: A more immediate impact for therapeutic approaches of current clinical research efforts is of major interest, which might be obtained by developing a noninvasive radiation dose-escalation strategy, and neutron capture therapy represents one such novel approach. Furthermore, some recent researches on neutron capture therapy have focused on using gadolinium as an alternative or complementary for currently used boron, taking into account several advantages that gadolinium offers. Therefore, in this study, we carried out feasibility evaluation for both single and multiple injections of gadolinium-based MRI contrast agent incorporated in calcium phosphate nanoparticles as neutron capture therapy agent., Methods: In vivo evaluation was performed on colon carcinoma Col-26 tumor-bearing mice irradiated at nuclear reactor facility of Kyoto University Research Reactor Institute with average neutron fluence of 1.8 × 10(12) n/cm(2). Antitumor effectivity was evaluated based on tumor growth suppression assessed until 27 days after neutron irradiation, followed by histopathological analysis on tumor slice., Results: The experimental results showed that the tumor growth of irradiated mice injected beforehand with Gd-DTPA-incorporating calcium phosphate-based nanoparticles was suppressed up to four times higher compared to the non-treated group, supported by the results of histopathological analysis., Conclusion: The results of antitumor effectivity observed on tumor-bearing mice after neutron irradiation indicated possible effectivity of gadolinium-based neutron capture therapy treatment.

Purpose: Although many studies have described various features of neuroimaging tests associated with intracranial hypotension, few have examined their validity and reliability. We evaluated the association between CSF leaks detected by radionuclide cisternography and abnormal MRI findings in the accurate diagnosis of intracranial hypotension., Patients/methods: We retrospectively assessed 250 patients who were suspected of intracranial hypotension and underwent subsequent radionuclide cisternography. We obtained 159 sagittal and 153 coronal T2-weighted MRI images and 101 gadolinium-enhanced T1-weighted MRI images. We assessed the CSF leaks in relation to a sagging brain, the maximum subdural space in sagittal and coronal images, and dural enhancement., Results: Overall, 186 (74%) patients showed CSF leaks on radionuclide cisternography. A sagging brain was observed in 21 (13%) of the 159 patients with sagittal MRIs. A sagging brain was not associated with CSF leaks (14% vs. 10%; p=0.49). Compared to patients without CSF leaks, those with CSF leaks tended to have a larger maximum subdural space in both the sagittal (3.7 vs. 4.1mm) and coronal (2.5 vs. 2.8mm) images; however, the differences were not significant (p=0.18 and p=0.53, respectively). Dural enhancement was observed only in one patient, who presented with CSF leaks on radionuclide cisternography., Conclusions: Our study, which included a relatively large population, did not find any association between the findings of radionuclide cisternography and MRI. Future research should focus on identifying more valid neuroimaging findings to diagnose intracranial hypotension accurately., (Copyright © 2014 Medical University of Bialystok. Published by Elsevier Urban & Partner Sp. z o.o. All rights reserved.)

Neutron capture therapy (NCT) is a promising non-invasive cancer therapy approach and some recent NCT research has focused on using compounds containing gadolinium as an alternative to currently used boron-10 considering several advantages that gadolinium offers compared to those of boron. In this study, we evaluated gadolinium-entrapped liposome compound as neutron capture therapy agent by in vivo experiment on colon-26 tumor-bearing mice. Gadolinium compound were injected intravenously via tail vein and allowed to accumulate into tumor site. Tumor samples were taken for quantitative analysis by ICP-MS at 2, 12, and 24 h after gadolinium compound injection. Highest gadolinium concentration was observed at about 2 h after gadolinium compound injection with an average of 40.3 μg/g of wet tumor tissue. We performed neutron irradiation at JRR-4 reactor facility of Japan Atomic Energy Research Institute in Tokaimura with average neutron fluence of 2×10¹² n/cm². The experimental results showed that the tumor growth suppression of gadolinium-injected irradiated group was revealed until about four times higher compared to the control group, and no significant weight loss were observed after treatment suggesting low systemic toxicity of this compound. The gadolinium-entrapped liposome will become one of the candidates for Gd delivery system on NCT., (Copyright © 2013 Elsevier Masson SAS. All rights reserved.)