OBJECTIVE: The expression of S100A6 (calcyclin), a member of the S100 calcium binding protein family, is elevated in a number of malignant tumors, but there have been few reports about its ...expression in gastric cancer. The aim of this study was to investigate its expression regulations in human gastric cancer and noncancerous mucosa, and the response to chemotherapeutic drugs in the gastric cancer cell line.
MATERIALS AND METHODS: In one matched gastric cancer sample pair, the serial analysis of gene expression (SAGE) experiment was conducted to compare the gene expression profiles between cancerous and adjacent tissues. To detect the expression regulations among more cancerous tissues, microarrays were carried out and real‐time RT‐PCR was conducted to validate the results. At the protein level, Western blot and tissue microarray (TMA) examination were further used to verify S100A6 expression. The regulation detection of S100A6 with flurouracil and doxorubicin at the mRNA and protein level was performed in the SGC7901 cell line.
RESULTS: With the SAGE strategy, five times more S100A6 tags were identified in cancer tissues than in normal tissues. With the cDNA microarray, S100A6 was found to be significantly upregulated in 21 of 42 (50%) nonselective gastric cancers. In 10 other paired samples, the upregulation of S100A6 was consolidated with RT‐PCR and Western blot analysis as well. A total of 14 endoscopy‐sectioned gastric noncancerous lesions and corresponding normal gastric mucosa were also applied to profile the gene expression; both cDNA microarray and RT‐PCR demonstrated no significant alterations of S100A6 at the mRNA level. TMA examination showed that 34 of 52 (65.4%) cancer samples were positively stained, while only 17 of 80 (21.3%) noncancerous lesions were positively detected and all nine normal mucosae were detected to be negative. An in vitro experiment showed that in the gastric cell line SGC‐7901, S100A6 mRNA was detected to be upregulated from 24 to 72 h after treatment with 5 mg/L 5‐flurouracil or 0.3 mg/L doxorubicin, and there were two wave upregulations of the S100A6 protein.
CONCLUSION: The observed regulated expression of S100A6 suggests that it is associated with gastric cancer tumorigenesis and quantitation of S100A6 is a promising tool for diagnosis of gastric cancer.
We report a comprehensive study of lattice dynamics of the Dirac node-line semimetal ZrSiS single crystal by Raman spectroscopy and first-principles calculations. The weak covalent bonding between ...ZrSiS layers is confirmed by the absence of low-frequency shear or breathing Raman modes down to 15cm−1. All six Raman-active optical phonons are identified at 300 K, whose energies and symmetries match our phonon-dispersion calculations and polarized Raman measurements. The thermodynamic stability is verified from 77 to 300 K, and, with increasing temperature, sizable softening of Raman modes is observed with broadened profiles. The first-order temperature coefficients are found to be linearly dependent on temperature. Furthermore, using multiple excitation laser wavelengths of 488, 514.5, 568, 647, and 785 nm, we find that three out-of-plane Raman modes are all nondispersive, and their normalized intensity resonances at different laser energies can be attributed to the different interband transitions. Our work provides detailed information of ZrSiS lattice vibrations, as well as the coupling between ZrSiS lattice vibrations and its electronic states.
Abstract
Fundamental insights into the reaction kinetics of organic–inorganic lead halide perovskite nanocrystals (LHP NCs) are still limited due to their ultrafast formation rate. Herein, we develop ...a water–oil interfacial synthesis of MAPbBr
3
NCs (MA=CH
3
NH
3
+
), which prolongs the reaction time to tens of minutes. This method makes it possible to monitor in situ the formation process of MAPbBr
3
NCs and observe successive spectral evolutions from 438 to 534 nm in a single reaction by extending reaction time. The implementation of this method depends on reducing the formation rate of PbBr
6
4−
octahedra and the diffusion rate of MA. The formation of PbBr
6
4−
is a rate‐determining step, and the biphasic system offers a favorable reaction condition to control the mass transfer of MA. The effects of temperature and concentration of precursor and ligand are investigated in detail.
Fundamental insights into the reaction kinetics of organic–inorganic lead halide perovskite nanocrystals (LHP NCs) are still limited due to their ultrafast formation rate. Herein, we develop a ...water–oil interfacial synthesis of MAPbBr3 NCs (MA=CH3NH3+), which prolongs the reaction time to tens of minutes. This method makes it possible to monitor in situ the formation process of MAPbBr3 NCs and observe successive spectral evolutions from 438 to 534 nm in a single reaction by extending reaction time. The implementation of this method depends on reducing the formation rate of PbBr64− octahedra and the diffusion rate of MA. The formation of PbBr64− is a rate‐determining step, and the biphasic system offers a favorable reaction condition to control the mass transfer of MA. The effects of temperature and concentration of precursor and ligand are investigated in detail.
Wachstum unter der Zeitlupe: Eine umfangreiche kinetische Studie des Wachstumsmechanismus von MAPbBr3‐Nanokristallen (NCs; MA=CH3NH3+) wurde durch eine Wasser/Öl‐Grenzflächensynthesemethode ermöglicht. Die gesamte Reaktionszeit der MAPbBr3‐NCs wird hierbei auf viele Minuten verlängert, indem die Bildungsrate der PbBr64−‐Oktaeder und die Diffusionsrate von MA verringert werden.
Accumulating evidence suggests that aberrant expression of microRNAs (miRNAs) is involved in several diseases, including cancer. This study aimed to investigate the miRNA expression pattern and its ...alteration following celecoxib intervention for human colorectal cancer (CRC). The miRNA expression profiles of CRC tissues, matched adjacent normal colorectal mucosae and HT-29 cells treated with celecoxib were determined using miRNA microarray, and further confirmed using the quantitative reverse transcription-polymerase chain reaction (Q-RT-PCR). The target genes of the aberrant miRNAs in HT-29 cells treated with celecoxib were further assessed through bioinformatic analysis. Results from this study demonstrated a significant increase in the expression of 35 miRNAs and a decrease in 30 miRNAs in the carcinoma tissues compared to the normal tissues (P<0.001). Of the 28 aberrantly expressed miRNAs, 20 were upregulated and 8 were downregulated in the HT-29 cells treated with celecoxib compared to the matched control cells (P<0.01). Furthermore, miR-552 was found to be correlated with clinical stage, lymph node and distant metastases (P<0.05). Stage and distant metastases revealed differential expression of miR-139-3p and grade disclosed aberrant expression of miR-142-3p. In addition, multiple target genes involved in several essential survival pathways were found be modulated by the aberrantly expressed miRNAs in HT-29 cells treated with celecoxib. Our data revealed that a common pattern of miRNA expression in the colorectum could distinguish malignant tissue from normal mucosa. Celecoxib inhibited HT-29 cell growth in vitro which was partly attributable to the altered expression of miRNAs. miRNAs may be involved in CRC tumorigenesis and can serve as potential therapeutic targets.
Although aberrations of peroxisome proliferator-activated receptor γ (PPARγ) and phosphatase and tensin homolog (PTEN) expression have been identified in several other cancer types, certain previous ...studies have revealed that PPARγ is abundant in normal and malignant tissue in the colon. The question of whether aberrant PTEN is involved in the initial stage or is a later event during colorectal carcinogenesis remains controversial. Relatively few studies have focused on the correlation of expression of PPARγ and PTEN in various tissues. In the present study, paraffin-embedded blocks from 139 patients with CRC, 18 adenomatous polyps and 50 paired paracancerous benign mucosas were selected and analysed in 4 tissue microarray (TMA) blocks comprising 104, 72, 130 and 54 cores, respectively. Expression of PPARγ and PTEN was examined using immunohistochemical staining on TMAs. There were no significant differences in the expression of PPARγ (P=0.055) and PTEN (P=0.100) between the colorectal cancers, adenomas and paracancerous mucosas. However, correlations of PPARγ expression with clinical stage (P=0.004) and PTEN expression with histological grade (P=0.006) and distant metastasis (P=0.015) were demonstrated in the CRC specimens. Although the differences in PPARγ and PTEN protein expression in human colorectal cancer may not be considered as early diagnostic markers, our results indicate that CRCs with a low expression or deletion of PTEN may progress towards invasion and even metastasis; thus, PTEN may have potential as a prognostic marker in human CRC.
This paper reports a novel micromachined integrated gyroscope and accelerometer based on gas thermal expansion. Using gas movement induced by alternating heat expansion in a micro chamber instead of ...a solid proof mass movement, a new type of micro gyroscope with a wide-range rotation detectability incorporating with 1-axis acceleration sensing is accomplished. Experiments demonstrate a good linearity of the rotation output in response to the angular rate from -3000 °/s to +3000 °/s and the acceleration output in response to the acceleration in the range of ±1g, which validate the simultaneous measurements of 1-axis angular rate and 1-axis acceleration in one chip. Meanwhile, the coupling effects among 3-axis rotations and accelerations are investigated experimentally to demonstrate low coupling effect via using thermal expansion flow.
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