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Purpose: Most differentiated thyroid cancer (DTC) patients have a good prognosis after surgery, but radioiodine refractory differentiated thyroid cancer (RAIR-DTC) patients have a significantly reduced 5-year survival rate (<60%) and a significantly increased recurrence rate (>30%). This study aimed to clarify the tescalcin (TESC) role in promoting the malignant PTC progression and providing a potential target for RAIR-DTC treatment. Methods: We analyzed TESC expression and clinicopathological characteristics using the Cancer Genome Atlas (TCGA) and performed qRT-PCR on tissue samples. TPC-1 and IHH-4 proliferation, migration, and invasion were detected after transfection with TESC-RNAi. Using Western blot (WB), several EMT-related indicators were detected. Moreover, iodine uptake of TPC-1 and IHH-4 after transfection with TESC-RNAi was detected. Finally, NIS, ERK1/2, and p-ERK1/2 levels were determined by WB. Results: TESC was significantly upregulated in DTC tissues and positively correlated with BRAF V600E mutation based on data analysis from TCGA and our center. Reduced expression of TESC in both IHH-4 (BRAF V600E mutation) and TPC-1 (BRAF V600E wild type) cells significantly inhibited cell proliferation, migration, and invasion. It downregulated the EMT pathway markers Vimentin and N-cadherin, and increased E- cadherin. Moreover, TESC knockdown significantly inhibited ERK1/2 phosphorylation and decreased NIS expression in DTC cells, with a remarkably increased iodine uptake rate. Conclusions: TESC was highly expressed in DTC tissues and may have promoted metastasis through EMT and induced iodine resistance by downregulating NIS in DTC cells. [ABSTRACT FROM AUTHOR]

In this work, we focus on Mg–Fe–O and Mg–Ni–O with Mg-rich compositions as positive-electrode materials for magnesium rechargeable batteries, and prepare them by a thermal decomposition of precipitates obtained by a solution method. It is indicated from X-ray diffraction patterns that the Mg–Fe–O and Mg–Ni–O samples have the spinel and rocksalt structures, respectively. X-ray absorption near edge structures indicate that Fe and Ni are trivalent and divalent, respectively, in the Mg-rich oxides. From charge/discharge cycle test, it is demonstrated that the Mg–Fe–O shows higher discharge capacity than the other and then has good cycle performance while keeping a discharge capacity over 100 mA h g–1. To gain deeper understanding on a relationship between the electrode properties and the crystal structure of the Mg–Fe–O, the crystal structure is investigated by a Rietveld refinement using a synchrotron X-ray diffraction profile and an analysis on total correlation functions. It is indicated from these studies that a vacant octahedral site in the spinel structure is partially occupied by the excess Mg in the synthesized sample. This structural feature might result in a stable charge/discharge cycle performance of the Mg-rich Mg–Fe–O. [ABSTRACT FROM AUTHOR]

The serrated flow behavior of Zr61.7Al8Ni13Cu17Sn0.3 bulk metallic glass with different aspect ratios was investigated. For the samples with aspect ratios below 2.0, the serrated flow behavior changes from uniform to nonuniform with increasing aspect ratios. The histograms of normalized stress drop magnitude all exhibit a peak shape and the mean stress drop magnitude increases with increasing aspect ratios. The serrated flow behavior is special and can be divided into two stages for the sample with aspect ratio of 2.5. At the first stage, the serrations exhibit a nonuniform behavior and the histogram of normalized stress drop magnitude exhibit a peak shape. At the second stage, the serration size increases significantly and the histogram of normalized stress drop magnitude exhibits a sporadic behavior. The reason for the appearance of the complex serrated flow behavior may probably be attributed to the complex interaction of multiple shear bands formed during the deformation. [ABSTRACT FROM AUTHOR]

Surface photovoltage inversion was found in PbI microcrystals, manifested as a significant increase in the absolute value of surface barrier height under sub-bandgap illumination. The corresponding surface states located at 0.43 eV above the valence band was detected, and the magnitude of photovoltage inversion was found to increase with increasing applied field strength. Besides, transient surface photovoltage responses and the time constants of the relaxation showed a dependence on the wavelength of illumination. When irradiated with 518-632 nm, the exciton together with the lead ion vacancy caused the population of holes in the surface state; while under 700-nm light irradiation, holes depopulation occurred on the surface. Transient surface photovoltage results show that the relaxation of the sub-bandgap surface photovoltage is exponential with long time constant. The different charge transportation processes agree well with the photocatalytic degradation of MO experiments under different wavelength irradiation. It is revealed that the exciton and the surface states could significantly affect the movement of photogenerated charge carriers, which lead to different degradation results of MO. These findings demonstrate a model involving photostimulated population of surface states for the study of surfaces of wide energy gap semiconductors, which shows the highly selective control of photogenerated charge carriers' behaviors by tuning the wavelength of irradiation. [ABSTRACT FROM AUTHOR]

Epithelial-mesenchymal transition (EMT) is a vital process in epithelial cancer invasion and metastasis. The induction of EMT by Six1 has been described as a common mode of cancer progression, which could promote breast cancer migration and invasion. In the study, we found that miR-204-5p could suppress the migration and invasion of breast cancer cell lines. Since overexpression of Six1 promote EMT, we identified a mechanism by which miR-204-5p inhibited the EMT by downregulating the Six1, which was mediated by a conserved miR-204-5p seed-matching sequence in the 3′-UTR of Six1 mRNA. We also identified that upregulation of Six1 could downregulate miR-204-5p expression, affecting the migration and invasion of breast cancer cell lines. In conclusion, the frequent upregulation of Six1 and/or downregulation of miR-204-5p in breast cancer may shift the equilibrium of these reciprocal regulations and lock breast cancer cells in the mesenchymal state. [ABSTRACT FROM AUTHOR]

Rhus chinensis is a well-known Chinese medicinal plant and chalcone synthase (CHS) is a key enzyme involved in flavonoid biosynthesis. In this paper, both the cDNA and the genomic sequence encoding CHS from R. chinensis were cloned and anaylzed. The ORF of RcCHS was 1,173 bp in size and predicted to encode a 390-amino acid polypeptide. Phylogenetic analysis showed that RcCHS was grouped into a branch with legume plants Glycine max and Medicago sativa. Real-time quantitative PCR showed that RcCHS gene expression were clearly tissue-specific, but not correlated with total anthocyanins accumulation as previously reported in some other plants. Moreover RcCHS was highly expressed in E.coli with pGEX-6P-1 vector, which will be helpful for further research on the structure, cellular localization and catalytic mechanisms of RcCHS. [ABSTRACT FROM AUTHOR]

Aquaporin genes are differentially expressed in primitive versus definitive erythropoiesis. Our previous research results showed that over-expression of aquaporin-1 (AQP1) gene greatly promotes the erythroid differentiation of erythroleukemia K562 cells, using benzidine staining and quantitative reverse-transcriptase polymerase chain reaction (qRT-PCR) analysis for representative erythroid-related genes, including γ-globin. But the molecular mechanisms underlying erythroid-specific gene regulation remain unknown. In this study, we demonstrated that AQP1 induced hemoglobins expression and altered erythroid gene expression by microarray analysis in K562 cells. The retroviral expression vector of AQP1 (pBABE-puro-AQP1) was constructed and infected K562 cells to establish a stable AQP1 over-expression cell line (K562-AQP1). AQP1 over-expression effectively inhibited cell proliferation and induced cell growth arrest in G1 phase of K562 cells. Then microarray profile was applied to analyze the differentially expressed genes which involved the mechanism of AQP1 in erythroid differentiation induction. The DAVID functional annotation clustering tool was used to identify biological functions enriched with the differentially expressed genes ( n = 466 genes) and to group genes into clusters based on their functional similarity. Significant enrichment of genes involved in 'oxygen transporter activity' ( p = 3.8E-7) including hemoglobins (HBD, HBG, HBB, HBE1, and HBQ1), HEMGN, and EBP42 were validated by qRT-PCR. Moreover, silencing of HEMGN by RNA interference in K562-AQP1 cells resulted in down-regulation of these genes. These data provide a better understanding of the role of AQP1 in erythroid differentiation, by promoting HEMGN induction and other potential signaling pathways associated with hemoglobin induction. [ABSTRACT FROM AUTHOR]

An electrochemical sensor is developed in this work based on the new perovskite-type nanomaterial LaNiTiO-FeO for sensitive determination of o-phenylenediamine (OPD). As-synthesized materials and the surface of as-fabricated electrochemical sensor are characterized by X-ray diffraction, atomic force microscope, and electrochemical impedance spectroscopy, respectively. The results of characterizations depict that the sample is of nanoscaled complex oxides consisting of perovskite structure and spinel structure, and has good conductive properties. The construction and experimental conditions of the electrochemical sensor are also optimized. The electrochemical properties of OPD at glassy carbon electrode modified with LaNiTiO-FeO are investigated in alkaline solution (NaOH). The new electrochemical sensor exhibits high electrocatalytic activity and stability in NaOH, and a promotion of electrochemical oxidation of OPD at low potentials can be obviously observed. A wide linear range is obtained from 1.0 × 10 to 7.0 × 10 M with a relative low detection limit of 0.15 μM (S/N = 3) under optimal conditions. Furthermore, the sensor exhibits reliable results for the determination of OPD in commercial samples. [ABSTRACT FROM AUTHOR]

Metallothioneins (MTs) are ubiquitous metal-binding, cysteine-rich, small proteins and play a major role in metal homeostasis and/or detoxification in all organisms. In a previous study, a novel full length MT gene was isolated from the freshwater crab ( Sinopotamon henanense), a species widely distributed in Shanxi and Henan Provinces, China. In this report, the gene for the crab MT was inserted into a PET-28a-6His-SUMO vector and recombinant soluble MT was over-expressed as fusions with SUMO in Escherichia coli. The recombinant fusion protein was purified by affinity chromatography and its biochemical properties were analyzed. In addition, on the basis of constructing SUMO-MT, two mutants, namely SUMO-MTt1 and SUMO-MTt2, were constructed to change the primary structure of SUMO-MT using site-directed mutagenesis techniques with the amino acid substitutions D3C and S37C in order to increase metal-binding capacity of MT. E. coli cells expressing SUMO-MT and these single-mutant proteins exhibited enhanced metal tolerance and higher accumulation of metal ions than control cells. The results showed that the bioaccumulation and tolerance of Zn, Cu and Cd in these strains followed the decreasing order of SUMO-MTt1 > SUMO-MTt2 > SUMO-MT. E. coli cells have low tolerance and high accumulation towards cadmium compared to zinc and copper. These results show that the MT of S. henanense could enhance tolerance and accumulation of metal ions. Moreover, we were able to create a novel protein based on the crab MT to bind metal ions at high density and with high affinity. Therefore, SUMO-MT and its mutants can provide potential candidates for heavy metal bioremediation. This study could help further elucidate the mechanism of how the crab detoxifies heavy metals and provide a scientific basis for environment bioremediation of heavy metal pollution using the over-expression of the crab MT and mutant proteins. [ABSTRACT FROM AUTHOR]

Key message: The gene and cDNA sequence encoding PAL from Chinese medicinal plant Rhus chinensis were cloned and analyzed, furthermore the biochemical properties, kinetic parameters, differential expression and key sites were studied. Abstract: Rhus chinensis is a well-known Chinese medicinal plant. Phenylalanine ammonia-lyase (PAL) is the first enzyme of phenylpropanoid pathway. Several recent studies suggested that PAL also play an important role in plant-aphid interaction. In this study, both the cDNA and the genomic sequence encoding PAL from Rhus chinensis (designated as RcPAL) were cloned and analyzed. The 3,833 bp gene contained a 1,342 bp intron and two extrons. The ORF was 2,124 bp and predicted to encode a 707-amino acid polypeptide. The results of real-time PCR showed that RcPAL expressed in all tested tissues and followed the order: stems > young leaves > petioles > roots > seeds > mature leaves. RcPAL was successfully expressed in E. coli with the pET-28a-RcPAL recombinant vector. The recombinant protein exhibited a high level of PAL activity. Biochemical properties and kinetic parameters of recombinant RcPAL were further studied. The results showed that the optimal temperature and pH for RcPAL activity were 45 °C and 9.0, and the K and K values were 7.90 mM and 52.31 s, respectively. The active sites and substrate selectivity site were also investigated with site-directed mutagenesis methods, suggesting that Phe is responsible for the substrate selectivity. To our knowledge, this was the first full-length PAL gene cloned and characterized from the family Anacardiaceae so far. [ABSTRACT FROM AUTHOR]

It is known that leukemia patients with extramedullary infiltration (EMI) have a worse prognosis than patients without it. Recent data indicate that the amyloid precursor protein (APP) is involved in cell adhesion, motility, and proliferation. The expression of APP and its prognostic significance in acute myeloid leukemia (AML) have not been studied. Our study shows that AML/ETO leukemia patients that overexpress APP easily get EMI and that their long-term survival rate is lower than patients without overexpression of APP. In an in vitro study, we knocked down APP in Kasumi-1 cells using small interfering RNA (siRNA). Transwell data show that siRNA/APP substantially impairs cell migration, but it does not inhibit cell proliferation. Furthermore, by quantitative real-time polymerase chain reaction and Western blot, we found that siRNA/APP decreases MMP-2 expression in vitro. Our study provides a novel clue that APP is involved in the extramedullary infiltration of leukemia by MMP-2. [ABSTRACT FROM AUTHOR]

Describes the design and application of 60mer oligonucleotide microarray in SARS coronavirus detection. Diagnostic capability of the microarray; Results indicating that the genome of SARS coronavirus can be detected in parallel by the 60mer oligonucleotide microarray which can improve the positive ratio of the diagnosis.

A straightforward approach for the synthesis of several new, aryl-substituted derivatives of the conformationally constrained phenylalanine analogue 1,2,3,4-tetrahydroisoquinoline-3-carboxylic acid (Tic) is described. Tic, nitrosubstituted at the 6 or 7 position, was prepared by base-catalyzed cyclization of diethyl acetamidomalonate with α,α-dibromo-4-nitro- o-xylene followed by decarboxylation and deacylation under refluxing conditions in aqueous HCl. Catalytic hydrogenation of nitro-Tic in the presence of 10% Pd/C afforded amino-Tic, which was then converted to iodo-Tic by a modified Sandmeyer reaction. Both amino-Tic and iodo-Tic can easily be transformed to other substituents. [ABSTRACT FROM AUTHOR]

A series of tri-and tetrapeptides sharing the amino-terminal dipeptide unit Tyr-Tic, found in the high-affinity delta opioid receptor antagonist Tyr-Tic-Phe-Phe (TIPP), was prepared and evaluated in receptor binding assays to explore the role(s) of the phenylalanine residues in positions 3 and 4. It was found that aromaticity of residues 3 and 4 is not required for high affinity, a lipophilic side chain in either location being sufficient, as evidenced by the high delta receptor binding affinities observed for the tetrapeptide Tyr-Tic-Ala-Leu and the tripeptide Tyr-Tic-Leu. These results support the suggestion of Temussi et al. [Biochem. Biophys. Res. Commun., 198 (1994) 933] that the aromatic side chain of the Tic residue corresponds to the aromatic side chain found in residues 3 or 4 in other delta-selective peptide series. [ABSTRACT FROM AUTHOR]

Nurudea zhengii Ren was identified by aphid morphological characteristics as well as the gall shape and host plant species, and placed in the tribe Fordini (Hemiptera, Aphididae, Eriosomatinae). Here, its whole genome was firstly sequenced by a genome-skimming method and its mitochondrial genome (mitogenome) was assembled to examine its genetic variation and phylogenetic position. The complete mitogenome of Nurudea zhengii is 15,392 bp in length, and consists of 13 protein-coding genes, 22 tRNAs, two rRNAs and one D-loop region. The gene order follows the mitogenomes of the other Rhus gall aphids, and similarly has an AT bias with the content of 83.9%. The majority strand is A-skewed and C-skewed, and shows opposite skewness for G-skewed in the minority strands. The ratios of nonsynonymous to synonymous substitution rates of protein-coding genes are lower than one except for ATP8, which indicated that ATP8 was undergoing positive selection. Phylogenetic analysis among the Rhus gall aphids based on 13 protein-coding genes and two rRNA genes showed that N. zhengii was sister to N. shiraii, and then clustered with N. yanoniella as a group with high support value. The two species, N. shiraii and N. yanoniella, share the same host plant Rhus chinensis, while the host of N. zhengii is R. hypoleuca. However, the phylogenetic relationship indicated that the taxa sharing the same host plant were not absolutely clustered as the closest taxa at least at species level. [ABSTRACT FROM AUTHOR]