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OBJECTIVE: To explore the underlying molecular mechanism of Notch1/cadherin 5 (CDH5) pathway in modulating in cell malignant behaviors of gastric cancer (GC). METHODS: We performed bioinformatic analyses to screen the potential target genes of Notch1 from cadherins in GC. Western blot and RT-PCR were conducted to detect CDH5 expression in GC tissues and cells. We utilized chromatin immunoprecipitation (CHIP) assays to assess the interaction of Notch1 with CDH5 gene. The effects of Notch1/CDH5 axis on the proliferation, invasion, migration and vasculogenic mimicry in GC cells were evaluated by EdU, wound healing, transwell, and tubule formation assays. RESULTS: Significantly increased CDH5 expression was found in GC tissues compared with paracancerous tissues and associated to clinical stage and poor overall survival (OS) in patients with GC. Notch1 positively regulate the expression of CDH5 in GC cells. CHIP assays validated that CDH5 was a direct target of Notch1. In addition, Notch1 upregulation enhanced the proliferation, migration, invasion and vasculogenic mimicry capacity of GC cells, which could be attenuated by CDH5 silencing. CONCLUSIONS: These results indicated Notch1 upregulation enhanced GC malignant behaviors by triggering CDH5, suggesting that targeting Notch1/CDH5 axis could be a potential therapeutic strategy for GC progression.
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l-cysteine, as an eco-friendly and nontoxic corrosion inhibitor, was directly covalently linked to the carbon/carbon double bonds of the GO flakes by a thiol-ene click reaction to avoid decreasing the number of hydrophilic oxygen-containing polar functionalities. The corrosion inhibition performances of Cys-GO toward Q235 steel (QS) in diluted hydrochloric acid were studied by electrochemical methods. The corrosion was a charge transfer-controlled process, and Cys-GO manifested as a mixed-type corrosion inhibitor. The corrosion inhibition efficiency (η) for QS showed a first-increase-and-then-decrease trend with increasing Cys-GO concentrations. The optimum concentration of Cys-GO was 15 mg L-1, and the according η value was up to 90%. The Cys-GO adsorbed on the QS surface to form a protective barrier was responsible for the efficient corrosion inhibition. Langmuir adsorption isotherm model was fitted well with the experiment data, indicating a monolayer adsorption. Furthermore, the coordinate covalent bonds, π-back-donation effect, and electrostatic attraction were responsible for the Cys-GO adsorption on the QS surface.
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In recent years, the role of gut microbiota in cancer treatment has attracted substantial attention. It is now well established that gut microbiota and its metabolites significantly contribute to the incidence, treatment, and prognosis of various cancers. This review provides a comprehensive review on the pivotal role of gut microbiota and their metabolites in cancer initiation and progression. Furthermore, it evaluates the impact of gut microbiota on the efficacy and associated side effects of anticancer therapies, including radiotherapy, chemotherapy, and immunotherapy, thus emphasizing the clinical importance of gut microbiota reconstitution in cancer treatment.
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Microbioma Gastrointestinal , Neoplasias , Radioterapia (Especialidade) , Humanos , Imunoterapia , Neoplasias/terapiaRESUMO
In this chapter, we mainly discuss the expression and function of aquaporins (AQPs) expressed in digestive system. AQPs are highly conserved transmembrane protein responsible for water transport across cell membranes. AQPs in gastrointestinal tract include four members of aquaporin subfamily: AQP1, AQP4, AQP5, and AQP8, and three members of aquaglyceroporin subfamily: AQP3, AQP7, and AQP10. In the digestive glands, especially the liver, we discuss four members of aquaporin subfamily: AQP1, AQP4, AQP5, and AQP8, three members of aquaglyceroporin subfamily: AQP7, AQP9, and AQP12. In digestive system, the abnormal expression of AQPs is closely related to the occurrence and development of a variety of diseases. AQP1 is involved in saliva secretion and fat digestion and is closely related to gastric cancer and chronic liver disease; AQP3 is involved in the diarrhea and inflammatory bowel disease; AQP4 regulates gastric acid secretion and is associated with the development of gastric cancer; AQP5 is relevant to gastric carcinoma cell proliferation and migration; AQP7 is the major aquaglyceroporin in pancreatic ß cells; AQP8 plays a role in pancreatic juice secretion and may be a potential target for the treatment of diarrhea; AQP9 plays considerable role in glycerol metabolism and hepatocellular carcinoma; Studies on the function of AQP10 and AQP12 are still limited. Further studies are necessary for specific locations and functions of AQPs in digestive system.
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Aquagliceroporinas , Aquaporinas , Neoplasias Hepáticas , Neoplasias Gástricas , Humanos , Aquaporinas/genética , Aquaporinas/metabolismo , Diarreia , Aquagliceroporinas/genéticaRESUMO
Aging is a major risk factor for chronic diseases and disability in humans. Nowadays, no effective anti-aging treatment is available clinically. In this study, oridonin was selected based on the drug screening strategy similar to Connectivity MAP (CMAP) but upon transcriptomes of 102 traditional Chinese medicines treated cell lines. Oridonin is a diterpenoid isolated from Rabdosia rubescens. As reported, Oridonin exhibits a variety of pharmacological activities, including antitumor, antibacterial and anti-inflammatory activities. Here, we found that oridonin inhibited cellular senescence in human diploid fibroblasts (2BS and WI-38), manifested by decreased senescence-associated ß-galactosidase (SA-ß-gal) staining. Compared with the elderly control group, the positive cell rate in the oridonin intervention group was reduced to 48.5%. Notably, oridonin prolonged the lifespan of yeast by 48.9%, and extended the average life span of naturally aged mice by 21.6%. Our mice behavior experiments exhibited that oridonin significantly improved the health status of naturally aged mice. In addition, oridonin also delayed doxorubicin-induced cellular senescence and mouse senescence. Compared with the model group, the percentage of SA-ß-gal positive cells in the oridonin treatment group was reduced to 59.8%. It extended the average lifespan of mice by 53.8% and improved healthspan. Mechanistically, we showed that oridonin delayed aging through the AKT signaling pathway and reversed the genetic changes caused by doxorubicin-induced cell senescence. Therefore, oridonin is a potential candidate for the development of anti-aging drugs.
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BACKGROUND: A lack of research on the association of trefoil factors (TFF) with gastric cancer and premalignant lesions (PML) in the general population is an important obstacle to the application of TFFs for gastric cancer screening. We aimed to analyze the association of TFFs with gastric cancer and PMLs in a general population. METHODS: We evaluated 3,986 adults residing in Wuwei, China. We collected baseline characteristics and gastric cancer risk factors, including TFFs, endoscopic diagnosis, and pathologic information. Three logistic regression models were generated to analyze the association between TFFs and gastric cancer, as well as PMLs. Adjusted odds ratio (OR) and 95% confidence intervals (95% CI) were calculated to determine the strength of association. RESULTS: Compared with pepsinogen (PG) and anti-Helicobacter pylori immunoglobulin G antibody (Hp-IgG), TFFs had significant association with gastric cancer and PMLs after adjusting for biomarkers and risk factors (P < 0.05). The ORs (95% CI) for TFF1 (1.67; 1.27-2.20), TFF2 (2.66; 2.01-3.51), and TFF3 (1.32; 1.00-1.74) were larger than the ORs for PGI (0.79; 0.61-1.03), PGI/II (1.00; 0.76-1.31), and Hp-IgG (0.99; 0.73-1.35) in the gastric cancer group. In the intestinal metaplasia (IM) group, not only the TFF3 serum level was the highest, but also the OR (1.92; 1.64-2.25) was the highest. CONCLUSIONS: TFFs were associated with risk of gastric cancer and PMLs. IMPACT: Serum TFFs can improve the screening of high-risk populations for gastric cancer.
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Helicobacter pylori , Neoplasias Gástricas , Fatores Trefoil , Adulto , Estudos de Coortes , Estudos Transversais , Humanos , Imunoglobulina G , Pepsinogênio A , Peptídeos , Fator Trefoil-2 , Fator Trefoil-3RESUMO
Several risk factors have been identified for the development of gastric adenocarcinoma (GAC), where the control group was usually a healthy population. However, it is unclear at what stage known risk factor exert their influence toward the progression to cancer. Based on the Wuwei Cohort, we enrolled 1,739 patients with chronic non-atrophic gastritis (no-CAG), 3,409 patients with chronic atrophic gastritis (CAG), 1,757 patients with intestinal metaplasia (IM), 2,239 patients with low-grade dysplasia (LGD), and 182 patients with high-grade dysplasia (HGD) or GAC to assess the risk factors between each two consecutive stages from no-CAG to GAC/HGD using adjusted logistic regression. We found that different groups of risk factors were associated with different stages. Age, occupation of farmer, low annual family income, Helicobacter pylori (H. pylori) infection, drinking, eating hot food, histories of gastritis and peptic ulcer were associated with the development of CAG. Age, illiteracy, H. pylori infection, smoking, eating hot food, eating quickly, and histories of gastritis and gallbladder diseases were associated with the progression to IM from CAG. Male, occupation of farmer and history of peptic ulcer were associated with the development of LGD from IM. Age, male and polyp history appeared to be risk factors associated with the development of GAC/HGD from LGD. In conclusion, it seems that most risk factors function more as a set of switches that initiated the GAC carcinogenesis. H. Pylori eradication and control of other risk factors should be conducted before IM to decrease the incidence of GAC.
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Gastric cancer (GC) is one of the most common digestive tumors in Northwest China. Previous sequencing analysis revealed that family with sequence similarity 153 member B (FAM153B) might be the primary driver gene of GC. In this study, we aim to explore the potential roles of FAM153B in GC. Microarray data were firstly obtained from public databases with the aim to evaluate the genetic expression of FAM153B between GC and normal tissues. The results were verified in immunohistochemistry (IHC). We also performed the co-expression network analysis and enrichment analysis to identify underlying mechanisms. A correlation analysis of FAM153B expression and immune infiltration was performed then. Furthermore, two GC cell lines were used to evaluate the effect of FAM153B on gastric cell proliferation by employing MTT and Edu assays. Our findings suggest that FAM153B is downregulated in tumoral tissue, and positively associated with unfavorable survival. The enrichment pathways of FAM153B were regulation of signaling receptor activity, DNA replication, cell cycle transition, chromosomal regulation, and so on. Besides, from the perspective of bioinformatics, the protein expression level of FAM153B is related to the degree of immune cell infiltration. In vitro, overexpression of FAM153B inhibit the proliferation of two cell lines. In summary, this study demonstrates that FAM153B might serve as an effective prognostic and therapeutic biomarker in GC.
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Neoplasias Gástricas , Humanos , Neoplasias Gástricas/genética , Neoplasias Gástricas/patologia , Prognóstico , Bases de Dados Factuais , China/epidemiologia , Regulação Neoplásica da Expressão GênicaRESUMO
Background: There are 9 traditional Chinese medicines (TCMs) combined with standard quadruple (SQ) available for the treatment of Helicobacter pylori (Hp)-associated gastritis, but their relative efficacy and best options in clinical decision making are unknown due to a lack of high-quality head-to-head randomized controlled trials (RCTs). This study aimed to explore which formulas are the most effective and/or safest for Hp-associated gastritis. Methods: We performed a search of electronic databases including PubMed, Web of Science, Cochrane Library, Embase, Chinese databases and South Korean database from inception to March 2022 to identify all relevant RCTs on the comparison between TCM combined with SQ and SQ for Hp-associated gastritis. Efficacy outcomes were the eradication rate of Hp and therapeutic response rate, and safety outcome was incidence of adverse reactions. Publication bias was assessed quantitatively using Egger's regression analysis and qualitatively using trim-and-fill method. Quality assessment was performed using Cochrane Risk of Bias, version 2 (ROB 2) tool. The Bayesian methods were applied to compare each treatment. Results: A total of 55 trials with 6,187 patients were involved. The experimental group included 9 TCMs combined with SQ. The control group was SQ. The pair-wise meta-analysis demonstrated that compared with control group, 8 TCMs combined with SQ could statistically improve the eradication rate of Hp in patients with gastritis, 9 TCMs combined with SQ could significantly improve the therapeutic response rate. Additionally, Banxia Xiexin decoction combined with SQ (BXS) could statistically decrease the incidence of adverse reactions. The network meta-analysis results showed that BXS, Xiangsha Liujunzi combined with SQ (XSS), and Huangqi Jianzhong decoction combined with SQ (HQS) was the best measures to effectively eradicate Hp, enhance therapeutic effect, and decrease adverse reactions, respectively. The results of trim-and-fill method indicated that the results were stable and less affected by publication bias. Conclusions: Compared with SQ, TCM combined with SQ generally has a better clinical effect and higher safety in patients with Hp-associated gastritis. BXS, XSS, and HQS are recommended based on the patient's condition and needs in clinical practice. Further high-quality double-blinded RCTs are warranted to validate the conclusions.
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5-Fluorouracil (5-FU) is a chemotherapeutic drug with a good anti-cancer effect on various types of cancers, such as colorectal cancer and breast cancer. However, previous studies have found that 5-FU could induce cognitive deficit in clinics. As ganoderic acid, isolated from Ganoderma lucidum, has a protective effect on neurons, this study investigated the effects of ganoderic acid (GA) against 5-FU-induced cognitive dysfunction with a series of behavioral tests and related indicators. Experimental results showed that GA significantly prevented the reduction of spatial and non-spatial memory in 5-FU-treated mice. In addition, GA not only ameliorated the damage to hippocampal neurons and mitochondrial structure, but also significantly improved abnormal protein expression of mitochondrial biogenesis related marker PGC-1α, and mitochondrial dynamics related markers MFN2, DRP1 and FIS1 in the hippocampi of 5-FU-treated mice. Moreover, GA could up-regulate the expression of neuronal survival and growth-related proteins, such as BDNF, p-ERK, p-CREB, p-Akt, p-GSK3ß, Nrf2, p-mTOR, and p-S6, in the hippocampi of 5-FU-treated mice. These results suggest that GA could prevent cognitive dysfunction in mice treated with 5-FU via preventing mitochondrial impairment and enhancing neuronal survival and growth, which provide evidence for GA as a promising adjunctive therapy for chemotherapy related cognitive impairment in clinics.
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Disfunção Cognitiva/prevenção & controle , Fármacos Neuroprotetores/farmacologia , Reishi , Triterpenos/farmacologia , Animais , Antineoplásicos/efeitos adversos , Modelos Animais de Doenças , Fluoruracila/efeitos adversos , Masculino , Aprendizagem em Labirinto/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos BALB C , Neurônios/efeitos dos fármacos , Fármacos Neuroprotetores/uso terapêutico , Fitoterapia , Distribuição Aleatória , Triterpenos/uso terapêuticoRESUMO
OBJECTIVE: This study aimed to determine the prevalence and risk factors of Helicobacter pylori infection across all age groups in Wuwei City, a high-risk area for gastric cancer in Northwest China. METHODS: We conducted this study from 2016 to 2017 in an urban and a rural community in Wuwei City. Stool antigen tests targeted individuals aged 0 to 3 years old, and 13 C-urea breath tests targeted individuals aged above 3 years. We selected participants based on hierarchical cluster sampling. We assessed the association between variables and H. pylori infection based on logistic regression models. RESULTS: Ultimately, the results of 2,163 participants (age: 0 to 77 years old) were included (1,238 minors and 925 adults) in the analysis. The overall prevalence of H. pylori infection was 35.6%. It increased with age, reaching the peak in the 30 to 39 age group, and then began to decline. In multivariate analysis, age was positively associated with prevalence of H. pylori infection, and factors negatively associated with the prevalence were drinking running water, the frequency of yoghurt consumption, and an annual household income of Renminbi (¥) 30,000-100,000 or 100,000 above. In the subgroup analyses, however, the same variables associated differently in different age groups. Additionally, we interestingly noticed that boarding, eating at school cafeterias over six times per week, and frequently drinking untreated water were independent predictors of H. pylori infection in junior and senior high school students. CONCLUSION: The prevalence of H. pylori infection is moderate and closely associated with the socioeconomic conditions of Wuwei City, as well as the sanitary situations and dietary habits of the participants in the city. Boarding, eating at school, and drinking untreated water are the main factors explaining the rising infection rate in junior-senior high school students.
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Infecções por Helicobacter , Helicobacter pylori , Neoplasias Gástricas , Adolescente , Adulto , Idoso , Criança , Pré-Escolar , China/epidemiologia , Estudos Transversais , Infecções por Helicobacter/complicações , Infecções por Helicobacter/epidemiologia , Humanos , Lactente , Recém-Nascido , Pessoa de Meia-Idade , Prevalência , Fatores de Risco , Neoplasias Gástricas/etiologia , Adulto JovemRESUMO
OBJECTIVES: To evaluate the prevalence of Helicobacter pylori infection and risk factors and to serotype the strains in Wuwei, located in north-western China, which has a high incidence of gastric cancer. METHODS: Helicobacter pylori infection was analysed in 21 291 adults by 14 C-urea breath test, and H. pylori antibody were detected in 9183 serum samples by latex immunoturbidimetric method. The correlation of H. pylori infection with demographic-economic, lifestyle factors and medical history among the participants was determined by questionnaire. The antibodies against H. pylori urease, VacA and CagA in serum were determined by dot immunobinding assay. RESULTS: The infection rate of H. pylori was 53.0%, and 90.1% of strains were type I strains. The H. pylori infection rate was higher among farmers (OR = 1.34, 95% CI: 1.19-1.50) and individuals who had a junior high school or higher education level (OR = 1.10, 95% CI: 1.06-1.15), and was lower in older individuals (OR = 0.86, 95% CI: 0.83-0.90), individuals with high income (OR = 0.93, 95% CI: 0.90-0.95), individuals with a habit of eating quickly (OR = 0.93, 95% CI: 0.87-0.99) and individuals who consumed more fruit and vegetables (OR = 0.90, 95% CI: 0.85-0.95). Individuals with history of cholecystitis/cholecystolithiasis, hypertension and asthma were negatively correlated with H. pylori infection (P < 0.05). CONCLUSION: The prevalence of H. pylori infection is high in Wuwei. The major prevalent strain is type I strain. Age, education, occupation, household income, consumption of fruit and vegetables, and habit of eating quickly are independent risk factors for H. pylori infection, which is also associated with individuals with a history of extragastric diseases.
OBJECTIFS: Evaluer la prévalence de l'infection à Helicobacter pylori et les facteurs de risque et déterminer le sérotype des souches à Wuwei, situé dans le nord-ouest de la Chine, où l'incidence du cancer gastrique est élevée. MÉTHODES: L'infection à H. pylori a été analysée chez 21.291 adultes par un test respiratoire à l'urée au 14 C, et des anticorps à H. pylori ont été détectés dans 9.183 échantillons de sérum par une méthode immuno-turbidimétrique au latex. La corrélation entre l'infection à H. pylori et les facteurs démographiques et économiques, le mode de vie et les antécédents médicaux des participants a été déterminée par un questionnaire. Les anticorps contre l'uréase de H. pylori, VacA et CagA dans le sérum ont été déterminés par un test dot par d'immuno-liaison. RÉSULTATS: Le taux d'infection à H. pylori était 53,0% et 90,1% des souches étaient du type I. Le taux d'infection à H. pylori est plus élevé chez les agriculteurs (OR = 1,34 ; IC95%: 1,19 à 1,50) et les personnes qui avaient un niveau d'instruction du premier cycle secondaire ou supérieur (OR = 1,10 ; IC95%: 01,06 à 01,15) et était plus faible chez les personnes âgées (OR = 0,86 ; IC95%: 0,83-0,90), les personnes à revenu élevé (OR = 0,93 ; IC95%: 0,90-0,95), les personnes ayant l'habitude de manger rapidement (OR = 0,93 ; IC9 %: 0,87-0,99) et les individus qui consommaient plus de fruits et de légumes (OR = 0,90 ; IC95%: 0,85-0,95). Les personnes ayant des antécédents de cholécystite/cholécystolithiase, d'hypertension et d'asthme avaient une corrélation négative avec l'infection à H. pylori (p <0,05 ). CONCLUSION: La prévalence de l'infection à H. pylori est élevée à Wuwei. La principale souche répandue est du type I. L'âge, l'éducation, la profession, le revenu du ménage, la consommation de fruits et de légumes et l'habitude de manger rapidement sont des facteurs de risque indépendants d'infection à H. pylori, qui est également associée à des personnes ayant des antécédents de maladies extra-gastriques.
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Infecções por Helicobacter/epidemiologia , Adulto , Anticorpos Antibacterianos/sangue , China/epidemiologia , Estudos de Coortes , Comportamento Alimentar , Feminino , Frutas , Infecções por Helicobacter/sangue , Helicobacter pylori/imunologia , Humanos , Incidência , Renda , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Prevalência , Fatores de Risco , VerdurasRESUMO
Novel N-doped carbon dots (CDs) were obtained through pyrolysis of ammonium citrate at 180 °C for 1, 2 and 3 h, and their corrosion inhibition effect on Q235 steel in 1 M HCl solution were evaluated through electrochemical impedance spectroscopy (EIS), potentiodynamic polarization (Tafel), scanning vibrating electrode technique (SVET) analysis. The changes of corrosion current density and impedance modulus of Q235 steel in inhibitor solutions showed that the as-prepared carbon dots presented a valid protective effect on steel in 1 M HCl solution. Meanwhile, the inhibition efficiency of three carbon dots exceeded 90% at 200 mg/L and the highest inhibitive efficiency was found for the carbon dots prepared at the reaction time of 2 h. The adsorption mechanism of all as-prepared carbon dots complied with the Langmuir adsorption model, containing chemical and physical adsorptions, which was also confirmed by X-ray photoelectronic spectroscopy (XPS) analysis.
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AIM: To evaluate the efficacy and safety of celecoxib combined with chemotherapy in the treatment of metastatic or postoperative recurrent gastric cancer. METHODS: This preliminary, three-center, clinical trial study was conducted between September 2010 and December 2016. In the experimental group (nâ=â100), patients were treated with celecoxib combined with chemotherapy, and chemotherapy alone was used in the control group. Progression-free survival (PFS) was considered as the primary efficacy parameter. Overall survival (OS), remission rate (RR), quality of life (QOL) and drug safety were considered as the secondary efficacy parameters. RESULTS: The PFS of the experimental group was 6 months, which was not significantly longer than that of the control group (5 months, Pâ=â.73). The average OS was not significantly different between the experimental group (12 months) and the control group (10 months, Pâ=â.59). The average OS of the COX-2 positive patients in the experimental group was 14 months and it was significantly longer than the 10-month OS in the control group (Pâ=â.01). The PFS of the COX-2 positive patients in the experimental group was 7.5 months, significantly longer than the 5-month PFS of patients in the control group (Pâ<â.001). No statistical significance was identified in the incidence of nausea, neutropenia, anorexia, peripheral neurotoxicity, diarrhea, vomiting, asthenia and thrombocytopenia. The EORTC QLQ-C30 questionnaire revealed that the overall QOL of the experimental group was significantly higher than that of the control group (Pâ<â.05). No statistical significance was found in the scores of functioning scale between the 2 groups. However, the scores of the symptom scale, especially for pain and fatigue in the experimental group was remarkably higher than that in the control group (Pâ<â.05). The overall score of EORTC QLQ-STO22 for the experimental group was considerably higher compared to that for the control group (Pâ<â.05). No statistical significance was identified in term of the domains of restrictions on feeding, dysphagia, anxiety, reflux, sense of taste, dry mouth, hair loss and body shape between the 2 groups (Pâ>â.05 for all mentioned outcomes). CONCLUSION: Celecoxib combined with chemotherapy offers more clinical benefits for COX-2 positive advanced gastric cancer patients.
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Antineoplásicos/administração & dosagem , Celecoxib/administração & dosagem , Gastrectomia/métodos , Recidiva Local de Neoplasia/tratamento farmacológico , Neoplasias Gástricas/terapia , Adolescente , Adulto , Idoso , Capecitabina/administração & dosagem , Quimioterapia Adjuvante , Intervalo Livre de Doença , Relação Dose-Resposta a Droga , Quimioterapia Combinada , Feminino , Seguimentos , Humanos , Injeções Intravenosas , Masculino , Pessoa de Meia-Idade , Metástase Neoplásica , Oxaliplatina/administração & dosagem , Estudos Retrospectivos , Neoplasias Gástricas/diagnóstico , Neoplasias Gástricas/secundário , Tegafur/administração & dosagem , Resultado do Tratamento , Adulto JovemRESUMO
Super-hydrophobicity polyhedral oligomeric silsesquioxane-modified graphene oxide (POSS-GO) was synthesized by one-step reaction between graphene oxide (GO) and aminopropylisobutyl polyhedral oligomeric silsesquioxane (POSS-NH2). Fourier transform infrared spectroscopy (FTIR) and X-ray photoelectron spectroscopy (XPS) spectra indicated that the POSS were successfully connected to the edge and surface of GO nanosheets. Scanning probe microscope (SPM) and transmission electron microscope (TEM) images demonstrated that the POSS-GO with a thickness of 1.58 nm presented a stably dispersion in anhydrous ethanol. Results from electrochemical behaviors showed that the proper incorporation of POSS-GO could availably improve the anticorrosion ability of epoxy based coatings in simulate marine environment (3.5 wt% NaCl solution). The good dispersion of POSS-GO helped to fill the original defect and enhanced the complication of penetration path. The super-hydrophobicity of POSS-GO was beneficial to the reduction of actual contact zone. The synergistic effect of good dispersion and super-hydrophobicity promoted the enhancement of anticorrosion ability for composite coatings.
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Decreased expression of miR-551b-3p has been identified in gastric cancer tissues but its biological role and underlying mechanism in this malignancy is poorly understood. In this study, we show that the expression of miR-551b-3p negatively correlates with the depth of tumour invasion and lymphatic metastasis, but it positively correlates with tumour differentiation and the patient survival. MiR-551b-3p negatively affects the proliferation, mobility and invasiveness of gastric cancer cells. LncRNA SMARCC2 inhibits the expression of miR-551b-3p through binding to its mRNA response elements in gastric cancer cells. Overexpression of LncRNA SMARCC2 enhances the proliferation and migration of gastric cancer cells, while inhibition of LncRNA SMARCC2 does the opposite. TMPRSS4 is a direct target gene of miR-551b-3p. We conclude that miR-551b-3p functions as a tumour suppressor gene in gastric cancer, and its function is regulated by LncRNA SMARCC2/miR-551b-3p/TMPRSS4 axis.
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Proteínas de Membrana/genética , MicroRNAs/genética , RNA Longo não Codificante/genética , Serina Endopeptidases/genética , Neoplasias Gástricas/genética , Animais , Linhagem Celular , Linhagem Celular Tumoral , Proliferação de Células/genética , Feminino , Regulação Neoplásica da Expressão Gênica , Genes Supressores de Tumor , Células HEK293 , Humanos , Masculino , Proteínas de Membrana/metabolismo , Camundongos Endogâmicos BALB C , Camundongos Nus , Pessoa de Meia-Idade , Serina Endopeptidases/metabolismo , Neoplasias Gástricas/metabolismo , Neoplasias Gástricas/patologia , Análise de Sobrevida , Transplante HeterólogoRESUMO
In this paper, CrAlSiN coatings with different interlayer designs (without interlayer, Cr interlayer, CrN interlayer and Cr/CrN interlayer) were successfully obtained on 316L stainless steel and single crystal silicon by multi-arc ion plating technique. Coating microstructure, mechanical, anticorrosion and tribological behaviors in artificial seawater were systematically investigated by XRD, SEM, XPS, TEM, nanoindentation, electrochemical workstation and frictional tester system. Results showed that the CrAlSiN layer presented a typical nanocrystalline/amorphous structure, which consisted of CrN, AlN and Si3N4 phases. The Cr/CrN interlayer could obviously improve the adhesion, hardness and toughness of CrAlSiN coating. Compared with single CrAlSiN coating, the corrosion current density of Cr/CrN/CrAlSiN coating system was improved by 2 orders of magnitude and its inhibition efficiency was up to 98.82%. Under high applied load (15 N) condition, the CrAlSiN coating with Cr/CrN interlayer revealed the lowest COF (0.107 ± 0.009) and wear rate (7.3 × 10-8 ± 8.4 × 10-9 mm3 N-1 m-1) in seawater, which primarily attributed to the synergistic effect of ideal adhesion force, outstanding toughness and effectively barrier ability.
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The conversion of arachidonic acid into prostaglandins by cyclooxygenase (COX)-2 contributes to the biological properties of malignant tumours. During the initiation and development of various tumours, the Notch family plays a key role. However, the association between COX2 and the Notch family in gastric cancer (GC) remains unclear. The present study aimed to clarify the mechanisms through which COX2 participates in the pathogenesis of GC. Quantitative PCR and western blot analysis were used to detect the expression of Notch family members and COX2 in human GC and paracancerous tissues, GES1 cells and GC cell lines (AGS, SGC7901, BGC823, and MGC803) treated with or without celecoxib, prostaglandin E2 and small interfering RNA (siRNA). A CCK8 assay was performed to detect the proliferation of GC cells transfected with siRNA against COX2 (siCOX2). A high mRNA expression of Notch1 and a decreased expression of Notch-1 intracellular active domain (N1IC) in GC were found to be related to the depth of invasion and TNM staging. The mRNA levels of Notch2, Notch3, Jagged1 and N2IC were found to be high in GC. A High expression of COX2 was associated with poorly differentiated and deeply invasive GC. COX2 and Notch1 exhibited an inverse expression pattern in the GES1 cells and different GC cell lines; the inhibition of COX2 increased Notch1 expression and activated the GC cells, whereas Notch1 downregulation had the opposite effect. Notch1 exhibited varying effects on Snail in the GC cell lines. The downregulation of COX2 expression significantly inhibited the proliferation of GC cells. On the whole, the expression of Notch signalling molecules differed in GC. COX2 inversely regulated Notch1 in GC and partially depended on the Notch1 signalling pathway in altering the expression of Snail.