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We determined 137Cs concentrations in deep water samples of the subtropical gyre in the South Pacific collected during the BEAGLE2003 cruise. This was done at an underground facility to achieve extremely low background γ-spectrometry, and we, therefore, obtained reliable values of 137Cs activity in the deeper layers. 137Cs activity in the layers between 2000 and 4500 m ranged from 7 ± 4 mBq m−3 to 25 ± 11 mBq m−3. The inventory of 137Cs in the water column from 2000 m to the sea bottom was estimated to be 20 ± 8 Bq m−2 to 94 ± 41 Bq m−2 in this region. [ABSTRACT FROM AUTHOR]

After stimulation with anti-CD3 antibodyin vitro, CD57+ T cells showed a greater susceptibility to apoptosis than CD57–αβT cell receptor (TCR)+ T cells (regularαβ T cells). The apoptotic fraction of CD57+ T cells showed an increased production of active caspase-3. An increase in both Fas expression and Fas-ligand (FasL) production was also observed in CD57+ T cells, whereas the expression of survivin was suppressed in CD57+ T cells compared to that of regularαβ T cells. CD57+ T cells display a biased expansion of a few Vβ T cell fractions in individuals, but such Vβ T cells were not specifically susceptible to CD3-mediated apoptosis. The TCR expression level of CD57+ T cells was much lower than that of regular T cells and anti-TCR antibody stimulation induced a smaller apoptotic proportion of CD57+ T cells than did anti-CD3 antibody. Although the CD3ℇ expression levels were similar in both T cell subsets, the CD3ζ level of CD57+ T cells was significantly higher than that of regular T cells. These results suggest that several apoptotic and anti-apoptotic molecules are involved in the CD3-induced apoptosis of CD57+ T cells and raise the possibility that the imbalance in expression of the CD3ℇ and CD3ζ chains may also contribute to the susceptibility of CD57+ T cells to undergo apoptosis. [ABSTRACT FROM AUTHOR]

A mutant strain of Escherichia coli with reduced susceptibility to imipenem, designated TL2740, was selected following serial passage of the parent strain, E. coli C600, in broth containing increasing concentrations of the carbapenem; the MIC of imipenem for TL2740 was eight-fold greater than that of the parent strain. The mutant also exhibited reduced susceptibilities to panipenem and biapenem and high-level resistance to mecillinam, but was as susceptible to meropenem, ceftazidime, piperacillin and the other beta-lactams tested as strain C600. The affinity of penicillin-binding protein (PBP) 2 of TL2740 for imipenem and meropenem was ten-fold less than that of C600, thereby providing an explanation for the mutant's reduced susceptibility to some carbapenems and mecillinam. However, this theory was confounded by the observation that the in-vitro activities of meropenem against both parent and mutant strains were virtually the same and by the fact that PBP 2 is the principal target of the antibiotic. Imipenem and aztreonam, which bind to PBP 2 and PBP 3 respectively, demonstrated synergic activity when tested in combination against both C600 and TL2740. These results suggest that the potent activity of meropenem against the mutant strain might also be due to a synergic effect resulting from simultaneous binding to both PBP 2 and PBP 3 and that the variable activities of the carbapenems against TL2740 were related to their different PBP binding profiles. Compared with C600, TL2740 appeared shorter on electron microscopy and had a longer generation time, discrepancies which are compatible with defective PBP 2 activities in the mutant strain. We also identified three clinical isolates of E. coli with beta-lactam susceptibility profiles which resembled that of TL2740 i.e. high-level resistance to mecillinam and low-level resistance to carbapenems, with the exception of meropenem to which these strains were susceptible; in common with TL2740, the combination of imipenem and aztreonam was synergic against these isolates. The genetic basis of resistance in all of the mecillinam-resistant strains, including TL2740, mapped close to lip at 15' on the E. coli chromosome with transductional analysis. The results strongly suggest that the reduced susceptibilities of the clinical isolates to carbapenems were due to mutations in the genes encoding the PBP 2s of these strains which affected their affinities for beta-lactam antibiotics. [ABSTRACT FROM AUTHOR]

We devised an accurate procedure with which to measure the affinities of beta-lactam antibiotics for penicillin-binding protein (PBP) 2' in methicillin-resistant Staphylococcus aureus (MRSA). In the present study, we used two isogenic strains of MRSA, on heterogeneous and the other homogeneous, derived from the methicillin-susceptible strain FDA209P, harbouring the mecA gene. In these MRSA strains, PBP2' was saturated by [14C]benzylpenicillin (PCG) at a concentration of 300 mg/L. In addition, the saturation of PBP2' by [14C]PCG required an incubation period of 30 min. According to these results, the precise affinities of beta-lactam antibiotics for PBP2' were determined by the 'accurate competition assay', using a high concentration of [14C]PCG and extending the reaction time. This procedure yielded lower IC50 values of beta-lactams than the 'usual competition assay'. However, each beta-lactam had almost the same affinity for PBP2' in heterogeneous and homogeneous strains. These results suggest there is a factor(s) other than PBP2' responsible for controlling resistance levels and the heterogeneity or homogeneity of MRSA strains. [ABSTRACT FROM AUTHOR]

Abstract Background The mental health community in Japan had started reviewing the country’s disaster mental health guidelines before the Great East Japan Earthquake, aiming to revise them based on evidence and experience accumulated in the last decade. Given the wealth of experience and knowledge acquired in the field by many Japanese mental health professionals, we decided to develop the guidelines through systematic consensus building and selected the Delphi method. Methods After a thorough literature review and focus group interviews, 96 items regarding disaster mental health were included in Delphi Round 1. Of 100 mental health professionals experienced in disaster response who were invited to participate, 97 agreed. The appropriateness of each statement was assessed by the participants using a Likert scale (1: extremely inappropriate, 9: very appropriate) and providing free comments in three rounds. Consensus by experts was defined as an average score of ≥7 for which ≥70% of participants assigned this score, and items reaching consensus were included in the final guidelines. Results Overall, of the 96 items (89 initially asked and 7 added items), 77 items were agreed on (46 items in Round 1, and 19 positive and 12 negative agreed on items in Round 2). In Round 2, three statements with which participants agreed most strongly were: 1) A protocol for emergency work structure and information flow should be prepared in normal times; 2) The mental health team should attend regular meetings on health and medicine to exchange information; and 3) Generally, it is recommended not to ask disaster survivors about psychological problems at the initial response but ask about their present worries and physical condition. Three statements with which the participants disagreed most strongly in this round were: 1) Individuals should be encouraged to provide detailed accounts of their experiences; 2) Individuals should be provided with education if they are interested in receiving it; and 3) Bad news should be withheld from distressed individuals for fear of causing more upset. Conclusions Most items which achieved agreement in Round 1 were statements described in previous guidelines or publications, or statements regarding the basic attitude of human service providers. The revised guidelines were thus developed based on the collective wisdom drawn from Japanese practitioners’ experience while also considering the similarities and differences from the international standards.