Reconstruction of uranium and plutonium isotopic signatures in sediment accumulated in the Mano Dam reservoir, Japan, before and after the Fukushima nuclear accident.

The Fukushima Dai-ichi Nuclear Power Plant (FDNPP) accident in Japan resulted in a major release of radionuclides into the environment. Compared to other radionuclides, few studies have investigated the fate of actinides in the environment. Accordingly, this research investigates the Pu composition in soil samples collected in paddy fields before and after the accident. Furthermore, the vertical distributions of Pu and U isotopic signatures, along with 137Cs activities, were measured in a sediment core collected in the Mano Dam reservoir, in the Fukushima Prefecture. Changes in the relative contributions of the major actinide sources (global fallout or FDNPP derived fallout) were investigated in sediment deposited in the reservoir. The distinct peak observed for all Pu isotope ratios (240Pu/239Pu, 241Pu/239Pu and 242Pu/239Pu) and for 137Cs concentrations in the sediment core was attributed to the Fukushima fallout, and coincided with the maximum atomic contribution of only 4.8 ±â€¯1.0% of Pu from the FDNPP. Furthermore, 236U/238U ratios measured in the sediment core remained close to the global fallout signature indicating there was likely no U from the FDNPP accident detected in the sediment core. More research is required on the environmental dynamics of trace actinides in landscapes closer to the FDNPP where there are likely to be greater abundances of FDNPP-derived Pu and U.

Association between sequevar and antibiotic treatment outcome in patients with Mycobacterium abscessus complex infections in Japan.

PURPOSE: Macrolide susceptibility differs between subspecies in the Mycobacterium abscessus complex, likely due to differences in erm(41) sequevars. Patients with M. abscessus complex infection generally show poor clinical outcomes in response to antibiotic treatment. Here, the association between genotype and treatment outcome was investigated. METHODOLOGY: We collected 69 isolates from 35 patients with non-cystic fibrosis bronchiectasis: 24 had M. abscessus complex lung disease and non-cystic fibrosis bronchiectasis, and 11 were colonized. Outcome analysis was performed in the 24 infected patients. Molecular analyses, including erm(41) and rrl sequencing, and variable-number tandem-repeat (VNTR) analysis of 69 isolates, from 24 infected and 11 colonized patients, were performed to elucidate the influence of genotype on antibiotic susceptibility. RESULTS: Among the 24 patients, 18 (14 infected with M. abscessus subsp. abscessus and 4 with M. abscessus subsp. massiliense) showed unfavourable outcomes; six (three infected with M. abscessus subsp. abscessus and three with M. abscessus subsp. massiliense) exhibited favourable outcomes. Patients with unfavourable outcomes showed acquired clarithromycin resistance (33.3 vs 0 %), mixed sequevars (38.9 vs 16.7 %) and differing VNTR patterns between initial and serial isolates (33.3 vs 16.7 %). In contrast, in the 11 colonized patients, M. abscessus subsp. abscessus C28 (sequevar 02) and M. abscessus subsp. massiliense were the most prevalent subspecies. CONCLUSION: Patients infected with multiple sequevars and genotypes were more likely to exhibit treatment failure and/or recurrence. The precise identification of subspecies and analyses of mycobacterial characteristics may help to predict treatment outcomes in patients with M. abscessus complex lung disease.

[A case of cryptococcal empyema successfully treated by debridement by medical thoracoscopy with local anesthesia].

Cryptococcal empyema is a rare disease which usually occurs in immunocompromised patients. We describe a 57-year-old man with diabetes mellitus with a mass-like shadow in the right middle lung field. Transbronchial lung biopsy of the right lung revealed numerous yeast-like fungi in fibrotic and necrotic lesions. These findings, together with positive serum cryptococcal antigen yielded a diagnosis of pulmonary cryptococcosis secondary to diabetes mellitus. Despite treatment with several anti-fungal drugs, and dyspnea and pleural effusion developed. He was referred to our hospital for further examination and therapy. The presence of positive cryptococcal antigen and numerous yeast-like fungi were confirmed cytologically in the pleural effusion. Therefore, we suspected that pulmonary cryptococcosis had perforated into the thoracic space and empyema had developed. Because antifungal drugs were ineffective, debridement of the fibrinopurulent material by medical thoracoscopy and chest drainage were performed. The clinical symptoms of this patient improved with antifungal treatment for 1 year, and we successfully treated the cryptococcal empyema without recurrence. Debridement by medical thoracoscopy and chest drainage were useful for this case of cryptococcal empyema.

The herbal medicine Shosaiko-to exerts different modulating effects on lung local immune responses among mouse strains.

Shosaiko-to (SST), a Chinese/Japanese traditional herbal medicine, has recently been demonstrated to increase lung interleukin-6 (IL-6) levels and to ameliorate pulmonary disorders in BALB/c mice (BALB). In the present study, we examined the effects of SST on lung cytokine levels and lipopolysaccharide (LPS)-induced lung injury in C57BL/6 mice (B6), which are known to show different immune responses from BALB due to the difference in genetic backgrounds. In B6, in contrast with BALB, SST decreased lung IL-6 levels and exacerbated LPS-induced lung injury. Investigation of the active components of SST suggested that multiple ingredients were supposed to be responsible for IL-6-attenuating activity in vivo. Further, we examined the effect of metabolites of major ingredients of SST on IL-6 production from lung immune cells in vitro. Saikogenin D and oroxylin A attenuated IL-6 production in LPS-stimulated alveolar macrophages of B6 more than in that of BALB. Liquiritigenin, which was previously reported to enhance IL-6 production in anti-CD3 monoclonal antibody-stimulated lung mononuclear cells of BALB, showed no effect on that of B6. These findings suggest that SST may have different, possibly even opposite, effects on lung immunity in hosts with different genetic backgrounds.