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Dissolved N2O is occasionally detected in surface and ground water in rice paddy fields, whereas little or no N2O is emitted to the atmosphere above these fields. This indicates the occurrence of N2O reduction in rice paddy fields; however, identity of the N2O reducers is largely unknown. In this study, we employed both culture-dependent and culture-independent approaches to identify N2O reducers in rice paddy soil. In a soil microcosm, N2O and succinate were added as the electron acceptor and donor, respectively, for N2O reduction. For the stable isotope probing (SIP) experiment, 13C-labeled succinate was used to identify succinate-assimilating microbes under N2O-reducing conditions. DNA was extracted 24 h after incubation, and heavy and light DNA fractions were separated by density gradient ultracentrifugation. Denaturing gradient gel electrophoresis and clone library analysis targeting the 16S rRNA and the N2O reductase gene were performed. For culture-dependent analysis, the microbes that elongated under N2O-reducing conditions in the presence of cell-division inhibitors were individually captured by a micromanipulator and transferred to a low-nutrient medium. The N2O-reducing ability of these strains was examined by gas chromatography/mass spectrometry. Results of the SIP analysis suggested that Burkholderiales and Rhodospirillales bacteria dominated the population under N2O-reducing conditions, in contrast to the control sample (soil incubated with only 13C-succinate). Results of the single-cell isolation technique also indicated that the majority of the N2O-reducing strains belonged to the genera Herbaspirillum (Burkholderiales) and Azospirillum (Rhodospirillales). In addition, Herbaspirillum strains reduced N2O faster than Azospirillum strains. These results suggest that Herbaspirillum spp. may have an important role in N2O reduction in rice paddy soils. [ABSTRACT FROM AUTHOR]

Although anti-Fcγ receptor antibodies (Abs) are detected in various autoimmune diseases, there have been no studies about the anti-Fcγ receptor Abs in alopecia areata (AA). To detect the anti-Fcγ receptor Abs in patients with AA and their clinical correlations, Serum samples from 72 patients with AA and 23 normal controls were examined by enzyme-linked immunosorbent assay assessing anti-Fcγ receptor Ab levels. Anti-Fcγ receptor I Abs were significantly frequently detected in patients with AA compared with normal controls. Furthermore, the detection of anti-Fcγ receptor I Abs significantly inversely correlated with the disease duration. These results suggest that anti-Fcγ receptor I Ab and Fcγ receptor I play an important role in the regulation of AA, are useful for a marker of the disease prognosis and are worth intense research for the reasonable and specific therapy of AA. [ABSTRACT FROM AUTHOR]