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Atmospheric-pressure low-temperature plasma treatment improves the bonding strength of adhesive resin cement as effectively as alumina sandblasting, and does not alter the zirconia crystal structure.

Recent studies point out that dissolved iron in seawater is bound to strong organic complexes that have stability constants consistent with microbially produced siderophores. In the present study, the growth and iron uptake of the coastal marine diatom Chaetoceros sociale were experimentally measured in culture experiments at 10ЊC in media containing a terrestrial fungal hydroxamate ferrisiderophore, desferriferrichrome (DFC)-Fe(III) (2 DFC : 1 Fe and 10 DFC : 1 Fe) complex with an Fe concentration of 100 nM. The DFC-Fe(III) (2 : 1) medium as well as EDTAFe(III) (2 : 1) medium in the previous study induced high cell yields and fast growth of C. sociale. The short-term iron uptake rate in the DFC-Fe(III) (2 : 1) medium aged for 9 d at 10ЊC was much faster than the uptake rates in the DFC-Fe(III) (2 : 1 and 10 : 1) media aged for 1 d and in the DFC-Fe(III) (10 : 1) medium aged for 9 d at 10ЊC. Furthermore, the DFC-Fe(III) (2 : 1) medium induced the fastest iron uptake rate in the organic-Fe(III) complexes [DFC-Fe(III), EDTA-Fe(III), citric-Fe(III) and fulvic-Fe(III)] and solid amorphous Fe(III) hydroxide [am-Fe(III)] media in the present and previous studies. The addition of excess DFC stopped iron uptake by C. sociale. The dissociation of DFC-Fe(III) complex in seawater was determined by simple filtration (0.025 m). Fast Fe(III) release was observed over 6-12 d in the DFC-Fe(III) (2 : 1) complex at 10ЊC, resulting from the thermal and microbial decomposition of the DFC complexed with Fe(III). This result is consistent with the faster iron uptake rate and growth rate of C. sociale observed in the DFC-Fe(III) (2 : 1) medium at 10ЊC. These results show that the dissolved DFC-Fe(III) complex in seawater supplies biologically available inorganic Fe(III) species, which may determine the iron uptake rate in culture media by providing bioavailable Fe as the DFC decomposes. The thermal, photochemical, and microbial decomposition of organic chelators complexed with Fe(III) in aquatic environments is probably one of the most important mechanisms for providing bioavailable inorganic Fe(III) species into these environments.Iron is one of the most important biological and geochemical trace elements in the ocean. Recently, many studies of iron speciation in seawater using competitive ligand equilibration/cathodic stripping voltammetry (CLE/CSV) (Gledhill and van den

The 7-valent pneumococcal conjugate vaccine (PCV7) is reported to decrease the incidence of community-acquired pneumonia (CAP) in children. To determine the annual incidence of CAP before the introduction of PCV7, we counted the number of children hospitalized with CAP between 2008 and 2009 in Chiba City, Japan. We investigated serotype and multilocus sequence typing (MLST) for Streptococcus pneumoniae isolates in CAP cases. The annual incidence of hospitalized CAP in children aged <5 years was 17.6 episodes/1000 child-years. In 626 episodes, S. pneumoniae was dominant in 14.7% and 0.8% of sputum and blood samples, respectively. The most common serotypes were 6B, 23F and 19F. The coverage rates of PCV7 were 66.7% and 80% in sputum samples and blood samples, respectively. MLST analysis revealed 37 sequence types. Furthermore, 54.1% of the sputum isolates and 40% of the blood isolate were related to international multidrug-resistant clones.

Heptavalent pneumococcal conjugate vaccine (PCV7) was introduced to Japan in 2010. We investigated the impact of PCV7 on childhood community-acquired pneumonia (CAP) and pneumococcal pneumonia (PP). Children aged <5 years living in Chiba city, Japan, who were admitted to hospitals were enrolled to estimate the incidence of CAP based on the mid-year population. PP was determined by the presence of Streptococcus pneumoniae in cultured blood and/or sputum samples of CAP patients. The incidence of CAP and S. pneumoniae isolated from PP patients was compared before (April 2008-March 2009) and after (April 2012-March 2013) the introduction of PCV7 immunization. The annual incidence of CAP was reduced [incidence rate ratio 0·81, 95% confidence interval (CI) 0·73-0·90]. When comparing post-vaccine with pre-vaccine periods, the odds ratio for PP incidence was 0·60 (95% CI 0·39-0·93, P = 0·024). PCV7-covered serotypes markedly decreased (66·6% in pre-vaccine vs. 15·6% in post-vaccine, P < 0·01), and serotypes 6C, 15A, 15C and 19A increased. Multidrug-resistant international clones in the pre-vaccine period (Spain6B-2/ST90, Taiwan19F-14/ST236) decreased, while Sweden15A-25/ST63 was the dominant clone in the post-vaccine period. A significant reduction in the incidence of both CAP hospitalizations and culture-confirmed PP of vaccine serotypes was observed at 2 years after PCV7 vaccination.