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Surface plasmon polaritons (SPPs) can be excited, meanwhile some peculiar optical phenomena will appear when light irradiates metal structures under some conditions. Based on photonic band gap theory, in this Letter we present a kind of SPP waveguide with multiple wavelength-channels. By using the Bragg effect and introducing some geometric defect layers into a quasi-periodic metal heterowaveguide, the multiple SPP forbidden bands (SPFBs) in a given waveband can be generated, and the multiple SPP pass bands (SPPBs) with narrow bandwidth in each SPFB can be realized. The SPP propagation in metal heterowaveguide is calculated by FDTD and transfer matrix methods. By selecting appropriate thickness, position and the number of defect layers, two SPPBs can be achieved in the SPFBs around 1.31 and 1.55 mm simultaneously. [ABSTRACT FROM AUTHOR]

Background: Chemoresistance severely deteriorates the prognosis of advanced gastric cancer (GC) patients. Several studies demonstrated that H. pylori (HP)-positive GC patients showed better outcomes after receiving chemotherapy than HP-negative ones. This study aims to confirm the role of HP in GC chemotherapy and to study the underlying mechanisms. Methods: The HP infection co-culture with GC cell lines were performed. The m 6 A-seq and NGS were used for bioinformatic analysis. Western Blot, qRT-PCR and IHC were adopted for expressions of METTL3, BRD2 and YTHDF2. The ATPGlow, flow cytometry and IF were used to detect the cell viability, DNA damage, apoptosis and pyroptosis. Luciferase reporter assay and CHIP were applied to explore the mechanisms. Results: The HP infection sensitized GC cells to 5-FU and induced expressions of METTL3 and YTHDF2. The HP infection promoted transcription of METTL3 through NF-κB pathway, therefore promoting the m 6 A modification level. METTL3 induced the m 6 A modification of BRD2 while YTHDF2 promoted the decay of mRNA of BRD2, both of which could promote the apoptosis and pyroptosis induced by 5-FU. In addition, BRD2 regulated the transcription of FLIP by importing FOXO4 into nucleus, thereby inhibiting the activation of Caspase-8, which was considered as the molecular switch of both apoptosis and pyroptosis. Conclusions: HP-induced m 6 A methylation could sensitize gastric cancers to 5-FU with activation of caspase-8 and induced apoptosis and pyroptosis. The Methylated BRD2 activated by NF-κB pathway regulates Caspase-8 by binding to FLIP-promoter FOXO4. This study provides new sights to the HP-positive gastric cancer chemotherapy., Competing Interests: Competing Interests: The authors have declared that no competing interest exists., (© The author(s).)

Ubiquitination plays a pivotal regulatory role in tumor progression. Among the components of the ubiquitin-proteasome system (UPS), ubiquitin-protein ligase E3 has emerged as a key molecule. Nevertheless, the biological functions of E3 ubiquitin ligases and their potential mechanisms orchestrating glycolysis in gastric cancer (GC) remain to be elucidated. In this study, we conducted a comprehensive transcriptomic analysis to identify the core E3 ubiquitin ligases in GC, followed by extensive validation of the expression patterns and clinical significance of Tripartite motif-containing 50 (TRIM50) both in vitro and in vivo . Remarkably, we found that TRIM50 was downregulated in GC tissues, associated with malignant progression and poor patient survival. Functionally, overexpression of TRIM50 suppressed GC cell proliferation and indirectly mitigated the invasion and migration of GC cells by inhibiting the M2 polarization of tumor-associated macrophages (TAMs). Mechanistically, TRIM50 inhibited the glycolytic pathway by ubiquitinating Phosphoglycerate Kinase 1 (PGK1), thereby directly suppressing GC cell proliferation. Simultaneously, the reduction in lactate led to diminished M2 polarization of TAMs, indirectly inhibiting the invasion and migration of GC cells. Notably, the downregulation of TRIM50 in GC was mediated by the METTL3/YTHDF2 axis in an m6A-dependent manner. In our study, we definitively identified TRIM50 as a tumor suppressor gene (TSG) that effectively inhibits glycolysis and the malignant progression of GC by ubiquitinating PGK1, thus offering novel insights and promising targets for the diagnosis and treatment of GC., Competing Interests: Competing Interests: The authors have declared that no competing interest exists., (© The author(s).)

Background: Gastric cancer (GC) continues to be one of the leading causes of cancer-related deaths globally. Diet significantly influences the incidence and progression of GC. However, the relationship between dietary intake and GC is inconsistent. Methods: A study was conducted with adults who participated in the National Health and Nutrition Examination Survey (NHANES) from 2003 to 2016 to investigate possible associations between 32 dietary factors and GC. To further detect potential causal relationships between these dietary factors and the risk of GC, a two-sample Mendelian randomization (MR) analysis was conducted. The primary method employed was the inverse variance weighted (IVW) analysis, and its results were further validated by four other methods. Results: Of the 35,098 participants surveyed, 20 had a history of GC. Based on the results of weighted logistic multivariate analysis, it was observed that there was a positive correlation between total fat intake [odds ratio (OR) = 1.09, 95% confidence interval (CI): (1.01-1.17), p = 0.03] and GC as well as negative association of dietary monounsaturated fatty acids (MUFAs) intake [OR = 0.83, 95% CI: (0.76-0.92), p < 0.001]. Further evaluations of the odds of GC across the quartiles of dietary MUFAs showed that the top quartile of total MUFA intake was associated with a lower likelihood of GC in three different models [model1: OR = 0.03, 95% CI: (0.00-0.25), p < 0.01; model2: OR = 0.04, 95% CI: (0.00-0.38), p = 0.01; model3: OR = 0.04, 95% CI: (0.00-0.40), p = 0.01]. For the MR analyses, genetic instruments were selected from the IEU Open GWAS project; IVW analysis showed that GC risk was not associated with MUFAs [OR = 0.82, 95% CI: (0.59-1.14), p = 0.23] or the ratio of MUFAs to total fatty acids [OR = 1.00, 95% CI: (0.75-1.35), p = 0.98]. Similar results were observed when using the other MR methods. Conclusion: The NHANES study revealed that consuming MUFAs was linked to a lower risk of GC, although the results of MR analyses do not provide evidence of a causal relationship. Additional research is therefore necessary to clarify these findings., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Zhang, Wang, Li, Liu, Xuan, Li, Li, Xia, Jiang, Xu, Fang, Wang, Zhang, Xu, Yang and Xu.)

Background: For gastric cancer (GC) patients with pylorus outlet obstruction (POO), whether laparoscopic surgery has advantages over open surgery remains unclear. This study aims to investigate the differences between patients with and without POO in open and laparoscopic groups and to determine the differences between laparoscopic distal gastrectomy (LDG) and open distal gastrectomy (ODG) in GC patients with POO., Methods: A total of 241 GC patients with POO who underwent distal gastrectomy at the Department of Gastric Surgery of the First Affiliated Hospital of Nanjing Medical University between 2016 and 2021 were included in this study. A total of 1,121 non-POO patients who underwent laparoscopic surgery and 948 non-POO patients who underwent open surgery from 2016 to 2021 were also enrolled in the study. We compared complication rates and hospital stays between open and laparoscopic groups., Results: There was no significant difference for LDG between GC patients with and without POO regarding the overall complication rates (P = 0.063), the Grade III-V complication rate (P = 0.673), and the anastomotic complication rate (P = 0.497) from 2016 to 2021. The patients with POO had longer preoperative hospital stay (P = 0.001) and postoperative hospital stay (P=0.007) compared to patients without POO. No significant difference was observed for open patients between POO and non-POO patients regarding the overall complication rate (P = 0.357), grade III-V complication rate (P = 1.000), and anastomosis-related complication rate (P = 0.766). Compared with open surgery in GC patients with POO (n = 111), the total complication rate of the LDG group was 16.2%, which was significantly lower than that of the open group (26.1%, P = 0.041). No significant differences in the Grade III-V complication rate (P = 0.574) and anastomotic complication rate (P = 0.587) were observed between laparoscopic and open groups. Patients receiving laparoscopic surgery had shorter postoperative hospital stay than open surgery (P = 0.001). More resected lymph nodes (LNs) were also observed in the laparoscopic group (P = 0.0145)., Conclusion: The comorbidity of GC with POO does not increase the complication rate after laparoscopic or open distal gastrectomy. In GC patients with POO, laparoscopic surgery shows advantages over open surgery with a lower overall complication rate, shorter postoperative hospital stay, and more harvested lymph nodes. Laparoscopic surgery is a safe, feasible, and effective treatment for GC with POO., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Wang, Zhang, Chen, Li, Li, Li, Liu, Xuan, Xia, Xu, Fang, Wang, Zhang, Xu, Yang and Xu.)

Background: Although ischemic stroke exhibits a high prevalence in the elderly population, the involved genes and pathways are poorly understood. In this study, we proposed to identify differentially expressed genes (DEGs) and constructed a circular RAN (circRNA)/long noncoding RNA (lncRNA)/microRNA (miRNA)-mRNA network associated with the pathogenesis of ischemic stroke by using bioinformatics analysis., Methods: We constructed a rat model of middle cerebral artery occlusion (MCAO) and conducted total RNA and microRNA sequencing in brain specimens from MCAO and normal rats. Transcriptome-wide expression patterns were analyzed and DEGs were defined by applying Ballgown and a cut of log2-transformed fold-change (log2FC) ≥ 1 (or ≤ -1) with a P value < 0.05. We exploited Pearson correlation analysis to determine the association between the circRNA/lncRNA/mRNA network and miRNAs ( P < 0.05 and corr ≤ -0.6), and the competing endogenous RNAs (ceRNA) interaction network was visualized with Cytoscape software and separated into subnetworks using the Molecular Complex Detection (MCODE) algorithm. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) were implemented for the pathway analysis of DEGs., Results: Upregulated DEGs were significantly enhanced in positive regulation of cell migration, response to wounding, blood vessel morphogenesis, inflammatory response, and cell activation; Downregulated DEGs were associated with control of the modulation of chemical synaptic transmission, synapse organization, regulation of membrane potential, and regulation of ion transport. KEGG-pathway analysis showed that DEG-enhanced pathways were associated with the pathways of TNF signaling pathway, Fluid shear stress and atherosclerosis, NF-kappa B signaling pathway, Lipid and atherosclerosis, Human cytomegalovirus infection, Osteoclast differentiation, Chemokine signaling pathway, IL-17 signaling pathway, Viral protein interaction with cytokine and cytokine receptor, and Cytokine-cytokine receptor interaction. We uncovered several novel lncRNAs (lnc&#95;00231, lnc&#95;002239, lnc&#95;004172; and a novel&#95;circ0001704), five miRNAs (miR-200b-3p, miR-223-3p, miR-200c-3p, miR-3084a-3p, and miR-664-2-5p), and the top-10 mRNAs (upregulated mRNAs were Pdgfa, Il1b, Gdf15, Fosl1, and Cxcl2; downregulated mRNAs were Prkar2b, Olfm3, Lrrc73, Tmem38a, and Dlgap3) that were involved in ischemic stroke., Conclusions: Through bioinformatic network analysis, we identified the underlying molecular mechanisms and key central genes that may contribute to an inflammatory response after cerebral infarction., Competing Interests: None., (AJTR Copyright © 2023.)