33 research outputs found
Extensive analysis of D7S486 in primary gastric cancer supports TESTIN as a candidate tumor suppressor gene
<p>Abstract</p> <p>Background</p> <p>High frequency of loss of heterozygosity (LOH) was found at D7S486 in primary gastric cancer (GC). And we found a high frequency of LOH region on 7q31 in primary GC from China, and identified D7S486 to be the most frequent LOH locus. This study was aimed to determine what genes were affected by the LOH and served as tumor suppressor genes (TSGs) in this region. Here, a high-throughput single nucleotide polymorphisms (SNPs) microarray fabricated in-house was used to analyze the LOH status around D7S486 on 7q31 in 75 patients with primary GC. Western blot, immunohistochemistry, and RT-PCR were used to assess the protein and mRNA expression of TESTIN (TES) in 50 and 140 primary GC samples, respectively. MTS assay was used to investigate the effect of TES overexpression on the proliferation of GC cell lines. Mutation and methylation analysis were performed to explore possible mechanisms of TES inactivation in GC.</p> <p>Results</p> <p>LOH analysis discovered five candidate genes (<it>ST7</it>, <it>FOXP2</it>, <it>MDFIC</it>, <it>TES </it>and <it>CAV1</it>) whose frequencies of LOH were higher than 30%. However, only <it>TES </it>showed the potential to be a TSG associated with GC. Among 140 pairs of GC samples, decreased <it>TES </it>mRNA level was found in 96 (68.6%) tumor tissues when compared with matched non-tumor tissues (<it>p </it>< 0.001). Also, reduced TES protein level was detected in 36 (72.0%) of all 50 tumor tissues by Western blot (<it>p </it>= 0.001). In addition, immunohistochemical staining result was in agreement with that of RT-PCR and Western blot. Down regulation of TES was shown to be correlated with tumor differentiation (<it>p </it>= 0.035) and prognosis (<it>p </it>= 0.035, log-rank test). Its overexpression inhibited the growth of three GC cell lines. Hypermethylation of <it>TES </it>promoter was a frequent event in primary GC and GC cell lines. However, no specific gene mutation was observed in the coding region of the <it>TES </it>gene.</p> <p>Conclusions</p> <p>Collectively, all results support the role of <it>TES </it>as a TSG in gastric carcinogenesis and that <it>TES </it>is inactivated primarily by LOH and CpG island methylation.</p
Low threading dislocation density and antiphase boundary free GaAs epitaxially grown on on-axis Si (001) substrates
The interactions between 1D defect threading dislocations and 2D defect antiphase boundaries and antiphase boundary annihilation in IIIāV materials on Si heteroepitaxy growth are revealed
All-MBE grown InAs/GaAs quantum dot lasers with thin Ge buffer layer on Si substrates
A high-performance IIIāV quantum-dot (QD) laser monolithically grown on Si is one of the most promising candidates for commercially viable Si-based lasers. Great efforts have been made to overcome the challenges due to the heteroepitaxial growth, including threading dislocations and anti-phase boundaries, by growing a more than 2 Āµm thick IIIāV buffer layer. However, this relatively thick IIIāV buffer layer causes the formation of thermal cracks in IIIāV epi-layers, and hence a low yield of Si-based optoelectronic devices. In this paper, we demonstrate a usage of thin Ge buffer layer to replace the initial part of GaAs buffer layer on Si to reduce the overall thickness of the structure, while maintaining a low density of defects in IIIāV layers and hence the performance of the InAs/GaAs QD laser. A very high operating temperature of 130 Ā°C has been demonstrated for an InAs/GaAs QD laser by this approach
Evolutionary Analysis of Structural Protein Gene VP1 of Foot-and-Mouth Disease Virus Serotype Asia 1
Foot-and-mouth disease virus (FMDV) serotype Asia 1 was mostly endemic in Asia and then was responsible for economically important viral disease of cloven-hoofed animals, but the study on its selection and evolutionary process is comparatively rare. In this study, we characterized 377 isolates from Asia collected up until 2012, including four vaccine strains. Maximum likelihood analysis suggested that the strains circulating in Asia were classified into 8 different groups (groups IāVIII) or were unclassified (viruses collected before 2000). On the basis of divergence time analyses, we infer that the TMRCA of Asia 1 virus existed approximately 86.29 years ago. The result suggested that the virus had a high mutation rate (5.745 Ć 10ā3 substitutions/site/year) in comparison to the other serotypes of FMDV VP1 gene. Furthermore, the structural protein VP1 was under lower selection pressure and the positive selection occurred at many sites, and four codons (positions 141, 146, 151, and 169) were located in known critical antigenic residues. The remaining sites were not located in known functional regions and were moderately conserved, and the reason for supporting all sites under positive selection remains to be elucidated because the power of these analyses was largely unknown
Multi-wavelength 128 Gbit sā1 Ī»ā1 PAM4 optical transmission enabled by a 100 GHz quantum dot mode-locked optical frequency comb
Semiconductor mode-locked lasers (MLLs) with extremely high repetition rates are promising optical frequency comb (OFC) sources for their usage as compact, high-efficiency, and low-cost light sources in high-speed dense wavelength-division multiplexing transmissions. The fully exploited conventional C- and L- bands require the research on O-band to fulfil the transmission capacity of the current photonic networks. In this work, we present a passive two-section InAs/InGaAs quantum-dot (QD) MLL-based OFC with a fundamental repetition rate of ā¼100 GHz operating at O-band wavelength range. The specially designed device favours the generation of nearly Fourier-transform-limited pulses in the entire test range by only pumping the gain section while with the absorber unbiased. The typical integrated relative intensity noise of the whole spectrum and a single tone are ā152 and ā137 dB Hzā1 in the range of 100 MHzā10 GHz, respectively. Back-to-back data transmissions for seven selected tones have been realised by employing a 64 Gbaud four-level pulse amplitude modulation format. The demonstrated performance shows the feasibility of the InAs QD MLLs as a simple structure, easy operation, and low power consumption OFC sources for high-speed fibre-optic communications
Contamination and human health risk of lead in soils around lead/zinc smelting areas in China
Pb/Zn smelting, an important economic activity in China, has led to heavy environmental pollution. This research reviewed studies on soil Pb contamination at Pb/Zn smelting sites in China published during the period of 2000 to 2015 to clarify the total levels, spatial changes, and health risks for Pb contamination in soils at local and national scales. The results show that Pb contents in surface soils at 58 Pb/Zn smelting sites in China ranged from 7 to 312,452Ā mgĀ kgā1 with an arithmetic average, geometric average, and median of 1982, 404, and 428Ā mgĀ kgā1, respectively (n = 1011). Surface soil Pb content at these smelting sites decreased from an average of 2466 to 659Ā mgĀ kgā1, then to 463Ā mgĀ kgā1 as the distance from the smelters increased from 2000Ā m. With respect to variation with depth, the average soil Pb content at these sites gradually decreased from 986Ā mgĀ kgā1 at 0- to 20-cm depth to 144Ā mgĀ kgā1 at 80- to 100-cm depth. Approximately 78Ā % of the soil samples (n = 1011) at the 58 Pb/Zn smelting sites were classified as having high Pb pollution levels. Approximately 34.2 and 7.7Ā % of the soil samples (n = 1011) at the 58 Pb/Zn smelting sites might pose adverse health effects and high chronic risks to children, respectively. The Pb/Zn smelting sites in the southwest and southeast provinces of China, as well as Liaoning province, were most contaminated and thus should receive priority for remediation.Pb/Zn smelting, an important economic activity in China, has led to heavy environmental pollution. This research reviewed studies on soil Pb contamination at Pb/Zn smelting sites in China published during the period of 2000 to 2015 to clarify the total levels, spatial changes, and health
risks for Pb contamination in soils at local and national scales. The results show that Pb contents in surface soils at 58 Pb/Zn smelting sites in China ranged from 7 to 312,452 mg kgā1 with an arithmetic average, geometric average, and median of 1982, 404, and 428 mg kgā1, respectively (n = 1011). Surface soil Pb content at these smelting sites decreased from an average of 2466 to 659 mg kgā1, then to 463 mg kgā1 as the
distance from the smelters increased from 2000 m. With respect to variation with depth, the average soil Pb content at these sites gradually decreased from 986 mg kgā1 at 0- to 20-cm depth to 144 mg kgā1 at 80- to 100-cm depth. Approximately 78 %
of the soil samples (n = 1011) at the 58 Pb/Zn smelting sites were classified as having high Pb pollution levels.
Approximately 34.2 and 7.7 % of the soil samples (n=1011) at the 58 Pb/Zn smelting sites might pose adverse health effects and high chronic risks to children, respectively. The Pb/Zn smelting sites in the southwest and southeast provinces of China, as well as Liaoning province, were most contaminated and thus should receive priority for remediation
LncRNA FOXD3-AS1 Promotes the Malignant Progression of Nasopharyngeal Carcinoma Through Enhancing the Transcription of YBX1 by H3K27Ac Modification
Background!#!Long noncoding RNAs (lncRNAs) can affect the progression of various tumors, including nasopharyngeal carcinoma (NPC). Here, lncRNA FOXD3-AS1 is highly expressed in NPC tissues through bioinformatics analysis and related to the malignant progression of NPC.!##!Methods!#!Bioinformatics analysis and real-time reverse transcription quantitative PCR(RT-qPCR) assay were applied to identify the expression of FOXD3-AS1 in NPC tissues and cells. Specific short hairpin RNAs (shRNAs) or overexpression plasmids were used to knockdown or upregulate FOXD3-AS1 in NPC cells. The effect of FOXD3-AS1 on proliferation and metastasis of NPC was confirmed by CCK8, colony formation, transwell assays !##!Results!#!FOXD3-AS1 was highly expressed in NPC tissues and cells. Knockdown of FOXD3-AS1 significantly inhibited proliferation, migration, and invasion of NPC cells !##!Conclusion!#!LncRNA FOXD3-AS1 is highly expressed and promotes malignant phenotype in NPC, which may provide a new molecular mechanism for NPC
The 3D Modeling System for Bioaerosol Distribution Based on Planar Laser-Induced Fluorescence
Although it is quite challenging to image and analyze the spatial distribution of bioaerosols in a confined space, a three-dimensional (3D) modeling system based on the planar laser-induced fluorescence (PLIF) technique is proposed in this paper, which is designed to analyze the temporal and spatial variations of bioaerosol particles in a confined chamber. The system employs a continuous planar laser source to excite the fluoresce, and a scientific complementary metal oxide semiconductor (sCMOS) camera to capture images of 2048 Ć 2048 pixels at a frame rate of 12 Hz. While a sliding platform is moving back and forth on the track, a set of images are captured at different positions for 3D reconstruction. In this system, the 3D reconstruction is limited to a maximum measurement volume of about 50 cm Ć 29.7 cm Ć 42 cm, with a spatial resolution of about 0.58 mm Ć 0.82 mm Ć 8.33 mm, and a temporal resolution of 5 s. Experiments were carried out to detect the PLIF signals from fluorescein aerosols in the chamber, and then 3D reconstruction was used to visualize and analyze the diffusion of aerosol particles. The results prove that the system can be applied to clearly reconstruct the 3D distribution and record the diffusion process of aerosol particles in a confined space
Application of Amorphous Zirconium-Yttrium-Aluminum-Magnesium-Oxide Thin Film with a High Relative Dielectric Constant Prepared by Spin-Coating
Amorphous metal oxide has been a popular choice for thin film material in recent years due to its high uniformity. The dielectric layer is one of the core materials of the thin film transistor (TFT), and it affects the ability of charges storage in TFT. There is a conflict between a high relative dielectric constant and a wide band gap, so we solved this problem by using multiple metals to increase the entropy of the system. In this paper, we prepared zirconium-yttrium-aluminum-magnesium-oxide (ZYAMO) dielectric layers with a high relative dielectric constant using the solution method. The basic properties of ZYAMO films were measured by an atomic force microscope (AFM), an ultraviolet-visible spectrophotometer (UV-VIS), etc. It was observed that ZYAMO thin films had a larger optical band when the annealing temperature increased. Then, metal-insulator-metal (MIM) devices were fabricated to measure the electrical properties. We found that the leakage current density of the device is relatively lower and the ZYAMO thin film had a higher relative dielectric constant as the concentration went up. Finally, it reached a high relative dielectric constant of 56.09, while the leakage current density was no higher than 1.63 Ć 10ā6 A/cm2@ 0.5 MV/cm at 1.0 M and 400 Ā°C. Therefore, the amorphous ZYAMO thin films has a great application in the field of high permittivity request devices in the future