[Synthesis and Fluorescence Properties of Rare Earth Ions Co-Doped CaMoO(4)].

In this paper, a series of CaMoO4 phosphor co-doped rare earth ions were prepared with chemistry co-precipitation method. The concentration of Pr(3+)/Tb(3+) and temperature had obvious influence on the luminescent properties. The crystal structures and spectrum characteristics of the samples were identified with X-ray powder diffraction (XRD) and fluorescence spectrophotometer (PL). According to XRD analysis, the main diffraction peaks of samples are consistent with the standard card (JCPDS 29-0351) of the diffraction peak data. This showed doped rare earth ions did not change matrix lattice structure. The emission spectrum excited by 275 nm exhibit sharp lines peaking at 488, 560, 621 and 560 nm assigned to the (3)P(0)­(3)H(4), (3)P(0)­(3)H(5)，(1)D(2)­(3)H(4) and (3)P(0)­(3)F(2) transitions of the Pr(3+) ions. The intensity of fluorescence reached the strongest when the concentration of the doping amount was 3%. The optimum calcination temperatures of CaMoO(4)∶0.03Pr(3+) and CaMoO(4)∶0.05Tb(3+) were 800 and 600 ℃. Furthermore, the intensity of excitation spectra and emission spectra are dependent on the concentration of the doping amount. The emission spectra intensities of CaMoO(4)∶Pr(3+) phosphors decrease and CaMoO(4)∶Tb(3+) phosphors firstly increase and then decrease because of concentration quenching effect with increasing Pr(3+) and Tb(3+) concentration. In addition, the luminescence properties of Pr(3+) ion in CaMoO(4)∶0.03Pr(3+), yTb(3+) system could be evidently improved with co-doping of Tb(3+) ions which was due to the efficient energy transfer process from Tb(3+) to Pr(3+) ions.

Identification of miR-4644 as a suitable endogenous normalizer for circulating miRNA quantification in hepatocellular carcinoma.

Background: Circulating microRNAs (miRNAs) have proved to be promising biomarkers for early diagnosis and therapeutic monitoring in cancers. Particularly for hepatocellular carcinoma (HCC), detection of circulating miRNA biomarkers as a new diagnostic approach has been written into the latest Guidelines for Diagnosis and Treatment of Primary Liver Cancer in China (2019 edition). However, no general consensus on an ideal endogenous normalizer for circulating miRNAs quantification has been reached, so it will affect the accuracy of quantitative results. In this study, we aim to identify a stable endogenous normalizer for analyzing circulating miRNAs. Methods: Candidate miRNAs were selected by screening dataset GSE104310, as well as data statistics and analysis. Five commonly reference genes were chosen for further comparison and verification. Then, the expression levels of these genes in serum were analyzed by quantitative reverse transcription PCR (RT-qPCR) among four groups, including patients diagnosed with HCC, chronic hepatitis B (CHB), liver cirrhosis, and healthy subjects. Furthermore, the stability of target genes was evaluated using geNorm, NormFinder, comparative ΔCq programs, and validated by database. We also explored the availability of the miRNA combination, and compared the performance difference between combination and individuals, as well as the selectivity of miRNA references in the combinations. Results: 11 candidate miRNAs were obtained, and miR-4644 stood out among these miRNAs, and proved to be much more stable than other endogenous miRNAs. Further study showed that miR-4644 exhibited higher stability and expression abundance than other commonly miRNA reference controls. Finally, we discovered the combination of miR-4644 and miR-16 revealed high performance in stability when compared to miRNA individuals. Furthermore, the combination consisted of references with closer nature could give rise to amplification effects in stability. Conclusions: Our findings demonstrated that miR-4644 is an ideal endogenous normalizer for circulating microRNA quantification in hepatocellular carcinoma. Besides, combining miR-4644 with miR-16 into a whole as a reference control would greatly improve the accuracy of quantification.

Molecular dissection of mercury-responsive transcriptome and sense/antisense genes in Medicago truncatula.

We described a newly developed approach, namely next-generation tag sequencing, to identify global gene transcripts and complexity regulated by heavy metals in Medicago truncatula. Two cDNA libraries were generated from M. truncatula seedlings: treated and non-treated with the toxic heavy metal mercury Hg(II). With the large number of read-mapped genes generated, we observed that most of the genes were differentially expressed between the two libraries. In addition, several classes of new transcripts including transcription factors, antisense transcripts, and stress responsive genes were detected. The forty genes most altered in expression levels were associated with tolerance to environmental stress and secondary metabolism. Validation of genes by quantitative RT-PCR confirmed the results from deep-sequencing. Most of genes coding for metal transporters, sulfate metabolism, and cell wall solidification were significantly altered by Hg exposure. We also examined altered expression ratios of sense and antisense (S-AS) transcripts between the two libraries. By analyzing strand-specific information of read sequences, S-AS transcripts were found to be enriched with metal treatment. The transcriptome sequences were analyzed further with Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) and showed diverse biological functions and metabolic pathways under the metal stress.