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Ultrathick aluminum honeycomb sandwich panels, which have high strength/stiffness-to-weight ratio, have been applied widely in satellites and other aerospace fields. However, the ultrathick aluminum honeycomb sandwich panels are difficult to be machined. In many cases, laser ablation is used for the microdrilling demand of aluminum honeycomb sandwich panels. The heat flux density is the key factor during laser machining, and the microdrilling parameters, including defocusing amount and incident angle, can lead to the change of the temperature fields of upper panel, cell walls, and lower panel. To study the microdrilling process quantitatively, the finite element model (FEM) is performed to evaluate the temperature evolution of aluminum honeycomb sandwich panels during continuous laser irradiation. Moreover, continuous laser microdrilling characteristics of upper panel, cell walls and lower panel are discussed via numerical simulation. The relative errors with respect to experimental results are in range of 8% showing that simulation results of laser microdrilling are reasonable. Thus, the mechanism of laser microdrilling revealed in this study can be significant for improving the processing quality of aluminum honeycomb sandwich panels. [ABSTRACT FROM AUTHOR]

The partial evaluation and assembly framework has recently been applied for processing subgraph matching queries over large-scale knowledge graphs in the distributed environment. The framework is implemented on the master-slave architecture, endowed with outstanding scalability. However, there are two drawbacks of partial evaluation: if the volume of intermediate results is large, a large number of repeated partial matches will be generated; and the assembly computation handled by the master would be a bottleneck. In this paper, we propose an optimal partial evaluation algorithm and a filter method to reduce partial matches by exploring the computing characteristics of partial evaluation and assembly framework. (1) An index structure named inner boundary node index (IBN-Index) is constructed to prune for graph exploration to improve the searching efficiency of the partial evaluation phase. (2) The boundary characteristics of local partial matches are utilized to construct a boundary node index (BN-Index) to reduce the number of local partial matches. (3) The experimental results over benchmark datasets show that our approach outperforms the state-of-the-art methods. [ABSTRACT FROM AUTHOR]

With the growing popularity and application of knowledge-based artificial intelligence, the scale of knowledge graph data is dramatically increasing. As an essential type of query for RDF graphs, Regular Path Queries (RPQs) have attracted increasing research efforts, which explore RDF graphs in a navigational manner. Moreover, path indexes have proven successful for semi-structured data management. However, few techniques can be used effectively in practice for processing RPQ on large-scale knowledge graphs. In this paper, we propose a novel indexing solution named FPIRPQ (Frequent Path Index for Regular Path Queries) by leveraging Frequent Path Mining (FPM). Unlike the existing approaches to RPQs processing, FPIRPQ takes advantage of frequent paths, which are statistically derived from the data to accelerate RPQs. Furthermore, since there is no explicit benchmark targeted for RPQs over RDF graph yet, we design a micro-benchmark including 12 basic queries over synthetic and real-world datasets. The experimental results illustrate that FPIRPQ improves the query efficiency by up to orders of magnitude compared to the state-of-the-art RDF storage engine. [ABSTRACT FROM AUTHOR]

Gastric cancer (GC) is one of the most common gastrointestinal malignancies. Ferroptosis is a new type of peroxidation-driven and iron-dependent cell death. However, the biological functions and exact regulatory mechanisms of ferroptosis in GC remain elusive. Here, we performed RNAi and gene transfection, cell viability assay, lipid peroxidation assay, reactive oxygen species (ROS) assay, glutathione assay, qRT-PCR, Western blotting, and transmission electron microscopy (TEM) to study ferroptosis in gastric cancer. The results revealed that silencing latent transforming growth factor β binding proteins (LTBP2) can significantly inhibit GC cell proliferation and decrease cellular GSH levels, reduce GPX4 activity, and increase ROS generation and malondialdehyde (MDA) levels, leading to ferroptosis in GC cells. In addition, we demonstrate that suppression of LTBP2 could regulate the p62-Keap1-Nrf2 pathway, thereby downregulating the GPX4 and xCT expression and upregulating the PTGS2 and 4HNE expression. Our findings described a new role of LTBP2 in regulating ferroptosis, which heralds the prospect of ferroptosis-mediated cancer therapy. [ABSTRACT FROM AUTHOR]

While cadherin (CDH) genes are aberrantly expressed in cancers, the functions of CDH genes in gastric cancer (GC) remain poorly understood. The clinical significance and molecular mechanisms of CDH genes in GC were assessed in this study. Data from a total of 1226 GC patients included in The Cancer Genome Atlas (TCGA) and Kaplan–Meier plotter database were used to independently explore the value of CDH genes in clinical application. The TCGA RNA sequencing dataset was used to explore the molecular mechanisms of CDH genes in GC. Using enrichment analysis tools, CDH genes were found to be related to cell adhesion and calcium ion binding in function. In TCGA cohort, 12 genes were found to be differentially expressed between GC para-carcinoma and tumor tissue. By analyzing GC patients in two independent cohorts, we identified and verified that CDH2, CDH6, CDH7 and CDH10 were significantly associated with a poor GC prognosis. In addition, CDH2 and CDH6 were used to construct a GC risk score signature that can significantly improve the accuracy of predicting the 5-year survival of GC patients. The GSEA approach was used to explore the functional mechanisms of the four prognostic CDH genes and their associated risk scores. It was found that these genes may be involved in multiple classic cancer-related signaling pathways, such as the Wnt and phosphoinositide 3-kinase signaling pathways in GC. In the subsequent CMap analysis, three small molecule compounds (anisomycin, nystatin and bumetanide) that may be the target molecules that determine the risk score in GC, were initially screened. In conclusion, our current study suggests that four CDH genes can be used as potential biomarkers for GC prognosis. In addition, a prognostic signature based on the CDH2 and CDH6 genes was constructed, and their potential functional mechanisms and drug interactions explored. [ABSTRACT FROM AUTHOR]

Circular RNA Profiling Reveals That circRNA 104433 Regulates Cell Growth by Targeting miR-497-5p in Gastric Cancer [Corrigendum]. [Extracted from the article]

Armadillo gene subfamily members (ARMCX1-6) are well-known to regulate protein-protein interaction involved in nuclear transport, cellular connection, and transcription activation. Moreover, ARMCX signals on cell pathways also implicated in carcinogenesis and tumor progression. However, little is known about the associations of the ARMCX subfamily members with gastric carcinoma. This study investigated the prognostic value of ARMCX subfamily mRNA expression levels with the prognosis of gastric carcinoma (GC). We retrieved the data of a total of 351 GC patients from TCGA database. Survival and gene set enrichment analyses were employed to explore the predictive value and underlying mechanism of ARMCX genes in GC. The multivariate survival analysis revealed that individually low expressions of ARMCX1 (adjusted P = 0.006 , HR = 0.620 , CI = 0.440 − 0.874) and ARMCX2 (adjusted P = 0.005 , HR = 0.610 , 95 % CI = 0.432 – 0.861) were related to preferable overall survival (OS). The joint-effects analysis shown that combinations of low level expression of ARMCX1 and ARMCX2 were correlated with favorable OS (adjusted P = 0.003 , HR = 0.563 , 95 % CI = 0.384 – 0.825). ARMCX1 and ARMCX2 were implicated in WNT and NF-kappaB pathways, and biological processes including cell cycle, apoptosis, RNA modification, DNA replication, and damage response. Our results suggest that mRNA expression levels of ARMCX subfamily are potential prognostic markers of GC. [ABSTRACT FROM AUTHOR]

Armadillo gene subfamily members (ARMCX1-6) are well-known to regulate protein-protein interaction involved in nuclear transport, cellular connection, and transcription activation. Moreover, ARMCX signals on cell pathways also implicated in carcinogenesis and tumor progression. However, little is known about the associations of the ARMCX subfamily members with gastric carcinoma. This study investigated the prognostic value of ARMCX subfamily mRNA expression levels with the prognosis of gastric carcinoma (GC). We retrieved the data of a total of 351 GC patients from TCGA database. Survival and gene set enrichment analyses were employed to explore the predictive value and underlying mechanism of ARMCX genes in GC. The multivariate survival analysis revealed that individually low expressions of ARMCX1 (adjusted P = 0.006 , HR = 0.620 , CI = 0.440 − 0.874) and ARMCX2 (adjusted P = 0.005 , HR = 0.610 , 95 % CI = 0.432 – 0.861) were related to preferable overall survival (OS). The joint-effects analysis shown that combinations of low level expression of ARMCX1 and ARMCX2 were correlated with favorable OS (adjusted P = 0.003 , HR = 0.563 , 95 % CI = 0.384 – 0.825). ARMCX1 and ARMCX2 were implicated in WNT and NF-kappaB pathways, and biological processes including cell cycle, apoptosis, RNA modification, DNA replication, and damage response. Our results suggest that mRNA expression levels of ARMCX subfamily are potential prognostic markers of GC. [ABSTRACT FROM AUTHOR]

Background: The role and mechanism of hsa_circRNA_104433 in gastric cancer (GC) are further elucidated. Materials and methods: CircRNA_104433 was selected by circRNA microarrays and GEO database. qRT-PCR was used to analyze the expression of circRNA_104433 in GC. The role of circRNA_104433 in GC cells was evaluated based on cell cycle progression, cell proliferation, cell apoptosis, and tumor xenograft experiment assay. To explore the mechanisms of circRNA_104433 in GC TCGA database, STRING version, qRT-PCR and luciferase assay were performed. Furthermore, the prognostic value of CDC25A in GC was determined based on the GEO database. Results: The level of circRNA_104433 showed upregulation in GC tissues, and the expression of it showed a positive correlation with the degree of differentiation and the size of the tumor. Knockdown of circRNA_104433 inhibited cell cycle transition, and cell proliferation, while promoted cell apoptosis in GC. CircRNA_104433 directly binds to miR-497-5p, which directly regulates CDC25A. The median survival period of GC patients with high expression levels of CDC25A was 21.3 months, which was shorter than those with low group expression of CDC25A (35.9 months). The cell cycle proteins CDK1, CDK2, CCNB1, PKMYT1, CDC20, CHEK1 and CDC25A were coexpressed with CDC25A. Conclusion: These findings suggested that knockdown of circRNA_104433 expression suppressed tumor development in GC. [ABSTRACT FROM AUTHOR]

Adrenergic receptor α1 (ADRA1) subfamily members, including ADRA1A, ADRA1B and ADRA1D, are understood to participate in cardiac disease and benign prostatic hyperplasia. In addition, adrenergic signals in cell pathways can promote the development of cancer. However, little is understood regarding the associations between ADRA1 subfamily members and gastric carcinoma (GC). The present study investigated the prognostic value of the ADRA1 subfamily genes in GC. Data from a total of 379 patients with GC were obtained from The Cancer Genome Atlas and Gene Expression Omnibus databases. Kaplan-Meier analysis and Cox regression analysis were used to determine associations with overall survival (OS) and to evaluate the median survival time using hazard ratios (HRs) and 95% confidence intervals (CIs). Multivariate survival analysis revealed that low expression levels of ADRA1A (HR, 0.595; 95% CI, 0.426–0.831; adjusted P=0.002) ADRA1B (HR, 0.576; 95% CI, 0.412–0.805; adjusted P=0.001) and ADRA1D (HR, 0.559; 95% CI, 0.398–0.787; adjusted P=0.001) were associated with a favourable OS. Joint-effects analysis demonstrated that combinations of low expression levels of ARDA1A, ARDA1B and ARDA1D were significantly associated with a favourable OS. Overall, the current results suggested that the mRNA expression levels of ARDA1 subfamily members may serve as potential prognostic markers for GC. [ABSTRACT FROM AUTHOR]

Background: Cohort studies have shown that neoadjuvant chemotherapy (NAC) is not associated with increased risk of postoperative complications and mortality as compared to upfront surgery (SURG). Objective: The aim of this study was to compare postoperative morbidity and mortality after NAC with SURG. Patients and methods: Patients who underwent gastrectomy with D2 lymphadenectomy for advanced gastric cancer (GC) between 2010 and 2017 were selected. The impact of neoadjuvant chemotherapy on surgical safety was investigated by using propensity score matching. Results: Three hundred and seventy-seven patients were included. After propensity score matching, 86 patients in each group were matched. The percentage of patients with one or more complications was 10.5% in NAC group and 15.1% in SURG group (P=0.361), there was no mortality developed in either group. The total blood loss was significantly more in the NAC group than that in the SURG group (320.79 vs 243.37 ml, P<0.04). In univariate and multivariate of the matched cohort, sex, age (<70), BMI (<24), ASA grade, surgical procedure (open vs laparoscopy), gastrectomy extent, cTNM and Charlson index comorbidity were not associated with postoperative complications (all P>0.05). Conclusion: This study showed that postoperative morbidity and mortality were similar for NAC group and SURG group. [ABSTRACT FROM AUTHOR]

Objectives: To explore the functional effects of miR-1284 on gastric cancer cells. Results: Overexpression of miR-1284 significantly reduced SGC-7901 cell proliferation, but improved apoptosis. However, miR-1284 suppression displayed the inversed impacts. Furthermore, the protein levels of p27, Bax, procaspase-3 and active caspase-3 were up-regulated by miR-1284 overexpression, but were down-regulated by miR-1284 suppression. The level of Bcl-2 was down-regulated by miR-1284 overexpression, while it was up-regulated by miR-1284 suppression. The level of p21 was unaffected. Conclusion: These results suggest that miR-1284 overexpression might be a suppressor for gastric cancer via controlling of cell proliferation and apoptosis. [ABSTRACT FROM AUTHOR]

Gastric cancer is one of the death-related malignant tumors worldwide. It remains a challenge for the diagnosis and treatment of gastric cancer. Special AT-rich sequence-binding protein 2 (SATB2) is a new tumor suppressive gene and plays important roles in many cancers. However, the role of SATB2 in gastric cancer is still unknown. In the present study, we demonstrated that downregulation of SATB2 was associated with shortened survival in patients with gastric cancer. Ectopic expression of SATB2 inhibited gastric cancer cell proliferation, colony formation, and migration. Overexpression of SATB2 repressed the expression of extracellular signal-regulated kinase 5 (ERK5), and activation of ERK5 restored the SATB2-induced inhibition of proliferation and migration in gastric cancer. This study provided evidence that SATB2 acted as a tumor suppressive gene gastric cancer, serving as a potential therapeutic target. [ABSTRACT FROM AUTHOR]