GaAs optoelectronic neuron arrays

A simple optoelectronic circuit integrated monolithically in GaAs to implement sigmoidal neuron responses is presented. The circuit integrates a light-emitting diode with one or two transistors and one or two photodetectors. The design considerations for building arrays with densities of up to 10^4 cm^-2 are discussed

Increased expression of Gremlin1 promotes proliferation and epithelial mesenchymal transition in gastric cancer cells and correlates with poor prognosis of patients with gastric cancer

Background/Aim: Gremlin1 (GREM1) plays an important role in certain malignancies by antagonising bone morphogenetic proteins and regulating angiogenesis directly/indirectly. The present study aimed to investigate the role of Gremlin1 in the development and progression of gastric cancer (GC). Materials and Methods: Expression of GREM1 in GCs was examined using quantitative real time PCR and The Cancer Genomic Atlas (TCGA) data. Influence on cellular functions was determined in both Gremlin1 knockdown and overexpression cell line models. Results: GREM1 expression was up-regulated in GCs, which was correlated with poorer survival. Increased GREM1 expression was significantly correlated with tumour growth/invasion and lymphatic metastasis. Gremlin1 promoted proliferation and tumourigenic capacity of GC cells in vitro. GREM1 expression was associated with epithelial mesenchymal transition (EMT), angiogenesis and lymphangiogenesis in GC. Conclusion: Increased GREM1 expression in GCs is associated with disease progression and poor prognosis in which EMT, angiogenesis and lymphangiogenesis are likely involved

Differential expression of CCN family members CYR611, CTGF and NOV in gastric cancer and their association with disease progression

CCN is an acronym for cysteine-rich protein 61 (CYR61), connective tissue growth factor (CTGF) and nephroblastoma overexpressed (NOV). Aberrations of certain CCN members including CYR61, CTGF, Wnt1-inducible signalling pathway protein (WISP)-1 and -3 have been reported in gastric cancer. The present study aimed to examine the clinical relevance of NOV along with CYR61 and CTGF in gastric cancer by analysing their transcript levels. CYR61, CTGF and NOV transcript expression in 324 gastric cancer samples with paired adjacent normal gastric tissues were determined using real-time quantitative PCR and the results were statistically analysed against patient clinicopathological data using SPSS software. NOV mRNA levels in gastric cancer tissues were significantly elevated when compared with levels in their paired adjacent non-cancerous tissues. Local advanced tumours with invasive expansion (T3 and T4) expressed higher levels of NOV (p=0.013) compared with the less invasive tumours (T1 and T2). CYR61 transcript levels were also significantly increased in gastric cancers compared with levels in the adjacent non cancerous tissues. Kaplan-Meier survival curves revealed that patients with CYR61-low transcript levels had longer overall survival (OS) (p=0.018) and disease-free survival (DFS) (p=0.015). NOV overexpression promoted the in vitro proliferation of AGS cells while the knockdown resulted in a reduced proliferation of HGC27 cells. A similar effect was observed for the invasion of these two gastric cancer cell lines. NOV expression was increased in gastric cancer which was associated with local invasion and distant metastases. Taken together, the expression of NOV and CYR61 was increased in gastric cancer. The elevated expression of CYR61 was associated with poorer survival. NOV promoted proliferation and invasion of gastric cancer cells. Further investigations may highlight their predictive and therapeutic potential in gastric cancer.Cancer Research Wales; Chinese Medical Research Scholarship of Cardiff UniversitySCI(E)[email protected]; [email protected]

EphB2 represents an independent prognostic marker in patients with gastric cancer and promotes tumour cell aggressiveness

Dysregulated expression of ephrin type-B receptor 2 (EphB2) has been linked with development and progression of solid tumours. In the current study we attempted to investigate the clinical relevance in GC and the effect of EphB2 expression on gastric cancer (GC) cells. EphB2 protein levels in GC and benign gastric tissues were determined using immunohistochemistry. EphB2 transcript expression in a GC cohort with GC tissue samples (n=171) and paired adjacent normal gastric tissues (n=97) was determined using qPCR. The EphB2 expression was over-activated using a CRISPR activator for the investigation of its cellular function. The expression levels of the EphB2 protein in the tumour tissues of tissue arrays were higher than the benign non-cancerous gastric tissues (P<0.05). EphB2 mRNA expression in GC tissues was also significantly elevated when compared with adjacent non-cancerous tissues (P<0.01). EphB2 activation promoted the migration and invasion abilities of the GC cell lines (P<0.01, respectively). In contrast, EphB2 activation significantly decreased the adhesion in GC cells (P<0.0001, respectively). The enrichment analysis of the correlated genes in a GC cohort indicates that EphB2 may function through mediating the cytokine-cytokine interaction, JAK-STAT and TP53 signaling pathways. In conclusion, EphB2 represents as a novel independent prognostic marker in GC. And activation of the EphB2 gene expression elevated the levels of migration and invasion, but suppressed adhesion of GC cells, indicating that EphB2 may act as a tumour promotor in GC. Our findings thus provide fundamental evidence for the consideration of the therapeutic potential of targeting EphB2 in GC

Design and analysis of miniaturized low profile and second-order multi-band polarization selective surface for multipath communication application

In this paper, a novel frequency selective surface (FSS) is designed; it has the characteristics of the low profile, second-order, multi-band, and the remarkable polarization selection properties. In the following, such an FSS having polarization selection characteristics will be referred to simply as a polarization selection surface (PSS). In a specific frequency band, the proposed PSS has a second-order selective transmission characteristic for TE and TM waves. Based on the coupling resonance filtering mechanism, the proposed PSS is composed of three metallic layers separated by two layers of dielectric substrates, which serves as the spatial form of the second-order microwave filter. The proposed PSS uses a sub-wavelength periodic structure array consisting of a non-resonant unit, and the unit size and the period within the range of 0.08λ 1 -0.15λ 1 , where the λ 1 =40.76 mm is the first passband wavelength of free space, so the PSS miniaturization characteristic is remarkable. The theoretical analysis and measure results show that the proposed bandpass PSS has good second-order polarization selection characteristics, out-of-band suppression level, and the flat transmission band, compared with the first-order bandpass PSS. In the range of incident angle of 0°-60°, it has a stable frequency response. It provides a reference for the design of a polarization wave generator and a polarization separation structure in a multipath communication system. © 2019 IEEE

Psoriasin overexpression confers drug resistance to cisplatin by activating ERK in gastric cancer

Psoriasin, a member of the S100 multigenic family, which is aberrantly expressed in a variety of human tumors, is considered as an attractive molecular target for cancer treatment. The present study aimed to characterize the role of psoriasin in gastric cancer (GC), the associated pathways through which it contributes to cancer development and progression, and the effect of psoriasin on cellular response to pre-operative chemotherapy in patients with GC. Expression of psoriasin mRNA and protein were analyzed using quantitative polymerase chain reaction and immunohistochemistry of gastric cancer cohorts, respectively. Gastric cancer cell models with differential expression of psoriasin were generated using stable cell lines that overexpressed psoriasin. The in vitro biological functions of the cells in response to psoriasin overexpression and to chemotherapeutic agents were assessed using various cell-based assays. Psoriasin was overexpressed in patients with advanced GC, and high psoriasin levels led to poor clinical outcomes. Increasing psoriasin expression in GC cell lines promoted cell proliferation, migration and invasion in vitro. Furthermore, psoriasin overexpression caused alterations in the levels of epithelial-mesenchymal transition-associated proteins, and activated the extracellular signal-regulated kinase signaling pathway. Additionally, higher levels of psoriasin expression were significantly associated a lack of response to neoadjuvant chemotherapy in patients with GC. Psoriasin overexpression tended to decrease the sensitivity of GC cells to cisplatin, potentially by inhibiting apoptosis or increasing the S-phase population. Taken together, these results indicate that psoriasin may be a promising therapeutic target for GC treatment, and a potential molecular marker to predict patient response to pre-operative chemotherapy

Isolation, Purification, Structure Characterization and Antioxidant Activity of Alkali-extracted Polysaccharide from Abalone Viscera

Objective: Alkali-extracted polysaccharides from Abalone viscera (Aavp) were isolated and purified. The structure and antioxidant activity of Aavp were studied, which would provide a reference for developing and applying polysaccharides. Methods: The crude alkali-extracted polysaccharide was prepared by hot alkali extraction and alcohol precipitation. After the purification of DEAE sepharose fast flow and sephacryl S-400 HR, the purified polysaccharide was obtained and subjected to the structural analysis and antioxidant activity assay, such as Gas chromatography (GC), high-performance liquid chromatography (HPLC), infrared spectroscopy (IR), and thermogravimetric analyzer (TGA), etc. Result: Four kinds of components (Aavp Ia, Aavp Ib, Aavp IIa, and Aavp IIb) were obtained from the crude polysaccharide. Because of the highest yield, Aavp IIa was selected for further structural analysis. Aavp IIa was composed of xylose and galactose, with a relative molecular weight of 166513 Da. IR characterized the α-glycosidic bond configuration. The composition of Aavp IIa was possible as follows: The molar percentage of the galactose 1→4 glycosidic bond was 11.81%, the galactose 1→3 glycosidic bond was 34.14%, and the galactose 1→2 glycosidic bond was 10.14%. The molar percentage of the xylose 1→3 glycosidic bond was 33.85%, and the 1→2 and 1→4 glycosidic bond was 10.06%. Thermogravimetric analysis showed that Aavp IIa was broken and decomposed at 226.4~332.6 °C, and the thermal weight loss rate was 43.65%. Antioxidant experiments showed that Aavp IIa had a scavenging rate of 85.89% for superoxide anion radicals and 62.17% for DPPH radicals, respectively, presenting a certain antioxidant activity. Conclusion: Aavp is a heteropolysaccharide with specific antioxidant activity

Inhibitory effects of Yangzheng Xiaoji on angiogenesis and the role of the focal adhesion kinase pathway

Angiogenesis is an essential event during the excessive growth and metastatic spread of solid tumours. Anti-angiogenic agents have become a new choice of therapy for patients with cancer. In the present study, we investigated the potential effect of Yangzheng Xiaoji, a traditional Chinese medicinal formula presently used in the treatment of several solid tumours including liver cancer and gastric cancer, on angiogenesis, in vitro. The human vascular endothelial cell line HECV was used. A Matrigel-based sandwich tubule formation assay was employed to assess in vitro angiogenesis, a colorimetric method for assessing in vitro cell growth. Electric cell-substrate impedance sensing (ECIS) was used to evaluate the adhesion and migration of endothelial cells. The effects on activation of focal adhesion kinase (FAK) were evaluated using western blotting and immunofluorescence methods. Yangzhen Xiaoji extract DME25 significantly inhibited tube formation (p=0.046 vs control). This was seen together with a concentration-dependent inhibition on cell-matrix adhesion and cellular migration. It was demonstrated that the focal adhesion kinase (FAK) inhibitor PF557328 had a significant synergistic effect on DME25-induced inhibition of cell adhesion, migration and tube formation. The study showed that DME25 inhibited the phosphorylation of FAK in endothelial cells. In conclusion, Yangzhen Xiaoji has a marked effect on angiogenesis, in vitro and that this effect is at least partly mediated by the focal adhesion kinase (FAK) pathway

Photoperiod decelerates the advance of spring phenology of six deciduous tree species under climate warming

Vegetation phenology in spring has substantially advanced under climate warming, consequently shifting the seasonality of ecosystem process and altering biosphere–atmosphere feedbacks. However, whether and to what extent photoperiod (i.e., daylength) affects the phenological advancement is unclear, leading to large uncertainties in projecting future phenological changes. Here we examined the photoperiod effect on spring phenology at a regional scale using in situ observation of six deciduous tree species from the Pan European Phenological Network during 1980–2016. We disentangled the photoperiod effect from the temperature effect (i.e., forcing and chilling) by utilizing the unique topography of the northern Alps of Europe (i.e., varying daylength but uniform temperature distribution across latitudes) and examining phenological changes across latitudes. We found prominent photoperiod-induced shifts in spring leaf-out across latitudes (up to 1.7 days per latitudinal degree). Photoperiod regulates spring phenology by delaying early leaf-out and advancing late leaf-out caused by temperature variations. Based on these findings, we proposed two phenological models that consider the photoperiod effect through different mechanisms and compared them with a chilling model. We found that photoperiod regulation would slow down the advance in spring leaf-out under projected climate warming and thus mitigate the increasing frost risk in spring that deciduous forests will face in the future. Our findings identify photoperiod as a critical but understudied factor influencing spring phenology, suggesting that the responses of terrestrial ecosystem processes to climate warming are likely to be overestimated without adequately considering the photoperiod effect