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Thioredoxins are oxidoreductases that help to maintain redox homeostasis in plants under abiotic stress. In this study, a new thioredoxin gene, SikTrxh, was cloned from Saussurea involucrata (Kar. & Kir.), a perennial herb that grows in the high alpine mountains of Central Asia. Bioinformatics analysis shows that the full-length cDNA of SikTrxh consisted of 565 bp with a 354-bp open reading frame and encoded a 117 amino acid protein. Using quantitative reverse transcription (RT) PCR, we found that the expression of the SikTrxh gene was induced by salt, cold, and drought stresses, suggesting that this protein played a significant role in plant defense. Subcellular localization confirmed that the protein was localized to the mitochondria. A vector carrying SikTrxh was inserted into tobacco, and successfully modified plants were identified by RT-PCR. Physiological indicators and antioxidant enzyme activities were measured under low temperature, and salt and drought stresses. Our results show that malondialdehyde content and relative electrolyte leakage increased in both wild-type and SikTrxh-overexpressing transgenic plants; however, these increases were significantly higher in the wild-type plants than in the transgenic plants. We also found that photosystem II photoinhibition was lower in the transgenic plants than in the wild-type plants, and that activities of reactive oxygen species-scavenging enzymes were higher in the transgenic plants than in the wild-type plants. We conclude that SikTrxh can reduce toxic effects of reactive oxygen species to protect the plasma membrane, thereby increasing plant resistance to abiotic stresses. [ABSTRACT FROM AUTHOR]

OBJECTIVE: Various studies have shown that aberrant expression of circular RNAs (circRNAs) has a pivotal role in multifarious cancers. However, the role of circRNAs in hepatoblastoma (HB) is not clearly understood. In the present study, we attempted to explore the underlying mechanism of hsa_cric_0000594 in HB along with its clinical importance. PATIENTS AND METHODS: In our research, the expression pattern of hsa_circ_0000594 in HB tissues and matched normal liver tissues was determined by in situ hybridization and RT-qPCR. Proliferation, viability, migration, and apoptosis of HB cell lines were detected via Cell Counting Kit-8 (CCK-8), colony formation, transwell, and flow cytometry assays. The interaction of hsa_circ_0000594 with miR-217 was investigated by Dual-Luciferase reporter assay. RESULTS: Expression levels of hsa_circ_0000594 were significantly upregulated in HB tissues compared with those in paired normal liver tissues and showed a clear association with the subtype of HB. The knockdown of hsa_circ_0000594 inhibited the malignant phenotype of HB. Bioinformatics analysis suggests that sirtuin 1 (SIRT1) may serve as a target gene of miR-217. CONCLUSIONS: Mechanically, hsa_circ_0000594 was identified to have a critical role in HB development through the hsa_circ_0000594/mir-217/SIRT1 regulatory axis, which might become a novel diagnostic marker and potential therapeutic target in HB. [ABSTRACT FROM AUTHOR]

Provides information on the photoluminescence of aluminum-gallium-arsenic heterostructures in the presence of high magnetic fields. Effect of magnetic fields on the interficial roughness; Residual impurities in ultra-pure materials; Distribution of the substitutional carbon impurities in discrete atomic layers near the interface.

A nonequilibrium computer simulation is performed to investigate the relaxation of a realistic polar solvent near a rapidly dissociating ion pair. The time evolution of the reaction coordinate, the ultrashort time scale changes in solvation energy and solvent forces, the local density response, the heating of certain librational degrees of freedom, and the time-dependent polarization are studied during the first 125 fs of the reaction. It is found that the relaxation behaviors in the anionic and cationic shells are very different. On average, the solvation process under study takes about 30-40 fs to break the original cage. After another 50 fs, the solvated ion pair reforms a new metastable structure, which feeds energy back into the reacting system to break the cage further. This procedure is apparently repeated many times until dissociation is complete. The results obtained in this work provide a graphic picture of some of the features of ultrashort dynamics of ionic photodissociation reactions in a polar medium. [ABSTRACT FROM AUTHOR]