Characterization of microRNAs and their target genes associated with transcriptomic changes in gamma-irradiated Arabidopsis

MicroRNAs (miRNAs) regulate gene expression in response to biotic and abiotic stress in plants. We investigated gamma-ray-responsive miRNAs in Arabidopsis wild-type and cmt3-11t mutant plants using miRNA microarray analysis. miRNA expression was differentiated between the wild-type and cmt3-11t mutants. miR164a, miR169d, miR169h, miR172b*, and miR403 were identified as repressible in the wild-type and/or cmt3-11t mutant in response to gamma irradiation, while miR827, miR840, and miR850 were strongly inducible. These eight miRNA genes contain UV-B-responsive cis-elements, including G-box, I-box core, ARE, and/or MBS in the putative promoter regions. Moreover, Box 4, MBS, TCA-element, and Unnamed_4, as well as CAAT- and TATA-box, were identified in these eight miRNA genes. However, a positive correlation between the transcriptions of miRNAs and their putative target genes was only observed between miR169d and At1g30560 in the wild-type, and between miR827 and At1g70700 in the cmt3-11t mutant. Quantitative RT-PCR analysis confirmed that the transcription of miR164a, miR169d, miR169h, miR172b*, miR403, and miR827 differed after gamma irradiation depending on the genotype (wild-type, cmt3-11t, drm2, drd1-6, and ddm1-2) and developmental stage (14 or 28 days after sowing). In contrast, high transcriptional induction of miR840 and miR850 was observed in these six genotypes regardless of the developmental stage. Although the actual target genes and functions of miR840 and miR850 remain to be determined, our results indicate that these two miRNAs may be strongly induced and reproducible genetic markers in Arabidopsis plants exposed to gamma rays.

Involvement of retinoic acid-induced peroxiredoxin 6 expression in recovery of noise-induced temporary hearing threshold shifts

All-trans retinoic acid (ATRA) is reported to reduce hair cell loss and hearing deterioration caused by noise-induced hearing loss (NIHL). The present study investigates the involvement of peroxiredoxin 6 (Prdx 6) in ATRA-mediated protection of temporary threshold shift of hearing. Mice fed with ATRA before or after exposure to white noise showed a faster recovery than untreated controls within 1 week, with a concomitant increase of cochlear Prdx 6 expression. Treatment of mouse auditory cells with ATRA induced Prdx 6 expression. A putative retinoic acid (RA)-response element (RARE) was identified in a murine Prdx 6 promoter region. Prdx 6 promoter activities were elevated in wild-type reporter plasmid-transfected cells, whereas no significant change in activity was in those with RARE-disrupted mutant reporter. RA receptor α (RARα) functions as a transactivator of Prdx 6 gene expression. These findings suggest that ATRA-induced Prdx 6 expression may be associated with rapid recovery from temporary NIHL.

Degradation of naturally contaminated polycyclic aromatic hydrocarbons in municipal sewage sludge by electron beam irradiation

This study was to evaluate the degradation efficiency of naturally contaminated polycyclic aromatic hydrocarbons in sewage sludge by using electron beam irradiation as a function of the absorbed dose. Degradation efficiency of PAHs was near to 90% at the absorbed doses 5 kGy. The degradation of PAHs was "first order" reaction rates with respect to absorbed dose. The electron beam irradiation was found effective in means of removing PAHs in domestic wastewater.

Synthesis and in vitro antibacterial activity of quaternary ammonium cephalosporin derivatives bearing oxazolidinone moiety

Several oxazolidinones having amine moiety were prepared to form a quaternary ammonium salt with cephalosporin nucleus, and antibacterial activity of the quaternary ammonium cephalosporin derivatives bearing oxazolidinone moiety were examined particularly with expectation of dual activity. However, the cephalosporin-oxazolidinone compounds revealed rather weaker antibacterial activity in vitro than their parent oxazolidinone and cephalosporin without showing any characteristic activity as expected.

Synthesis and antifungal activities of N-aryl-4-phenyl-3-(4-phenoxyphenyl)butanamides

Various N-aryl-4-phenyl-3-(4-phenoxyphenyl)butanamides (2 and 3) were tested for fungicidal activities against Pyricularia oryzae, Rhizoctonia solani, Botrytis cinerea, Phytophthora infestans, Puccinia recondita, and Erysiphe graminis in vivo. Butanamides (2 and 3a) that have an electron withdrawing group (Cl, F) attached to the meta position of the phenyl ring showed good to excellent activities against Pyricularia oryzae, Puccinia recondita, and Erysiphe graminis in high concentration while those that have a strong electron withdrawing group (CN, NO2) or electron donating group (OCH3, CH3) attached to the meta position did not show good activities against all test fungi at 250 mg L-1. The antifungal activities of the compounds synthesized were compared with reference compounds such as Tricyclazole, Moncozeb, and Benomyl.

Synthesis and in vitro antibacterial activity of C-3' pyridinium cephalosporin derivatives

The quaternary ammonium cephalosporin derivatives were prepared with various pyridines substituted at the 3 or/and 4 position. Their in vitro antibacterial activities were determined and substituent effect on pyridine nucleus was studied. Preparation of substituted pyridines are also described.

Synthesis and antibacterial activity of 1 beta-methylcarbapenem having a 1,3-diazabicyclo[3.3.0]octan-4-one moiety, Part II

The synthesis of a new series of 1 beta-methylcarbapenems having a 1,3-diazabicyclo[3.3.0]octan-4-one moiety is described. Their in vitro antibacterial activities against both Gram-positive and Gram-negative bacteria are tested and the effect of substituent on the bicyclic ring was investigated. A particular compound (11 h) having aminoethyl group showed the most potent antibacterial activity.

Transesophageal echocardiographic identification of left upper pulmonary venous obstruction caused by compression by spontaneous pseudoaneurysm of the descending thoracic aorta

Pseudoaneurysm of the aorta usually occurs as a complication of nonpenetrating trauma or deceleration injuries. Spontaneous pseudoaneurysm of the aorta is, however, extremely rare. Pulmonary veins can be affected in this situation because of the anatomic proximity. However, it is often overlooked during clinical examination, during routine echocardiography, and even at invasive angiography. This report describes the importance of transesophageal echocardiography in the detection of pulmonary vein compression, which is not suspected during other noninvasive and invasive diagnostic tests, in a patient with spontaneous pseudoaneurysm of the descending thoracic aorta.

Positive and negative supervisory experiences reported by counseling trainees

2 reviewers identified themes from audiotaped interviews with 6 counseling trainees about their positive and negative experiences during supervision.