RESUMO
OBJECTIVE: Gastrointestinal metaplasia (GIM) has a close relationship with gastric cancer (GC), but it is unclear how to judge which GIM could develop into GC. This study aimed to assess the role of CDX2 and its association with Helicobacter pylori (H.pylori) genotypes in GIM. METHODS: CagA and vacA genes were identified via PCR in 466 H. pylori-positive gastric tissues, including gastritis (n=104), GIM diagnosed endoscopically (GIM-1; n=82), gastric cancer (GC; n=173), and paired adjacent GIM tumors resected surgically (GIM-2; n=107). GIM was subclassified per the HID- AB pH2.5-PAS as follows: type I (n=23), type II (n=43), and type III (n=16) in GIM-1; type I (n=8), type II (n=40), and type III (n=59) in GIM-2. CDX2 expression was evaluated immunohistochemically. RESULTS: In GIM-1, the infection rate of vacAm2 (55.8%) and vacAs1m2 (53.5%) was higher in subtype II than in others (P<0.05), while that of vacAm1 (49.2%) and vacAs1m1 (33.9%) was higher in subtype III than in others. The cagA+ rate was higher in subtypes I (75.0%) and III (64.4%) than in subtype II (40.0%; P<0.05) respectively. CDX2 was upregulated in subtype I than in subtypes II and III in GIM-1 and GIM-2. In GIM-2 and GC, CDX2 was downregulated in vacAm1, vacAs1m1, and cagA+ (P<0.05). The predominant genotype was vacAs1m2 in subtype II of GIM-1, CDX2 expression remaining unaltered; however, the predominant genotype was cagA+ vacAs1m1 in subtypes II and III of GIM-2, negatively correlated with CDX2 expression. CONCLUSION: These GIM subtypes (cagA+ vacAs1m1 H. pylori-positive GIM with negative CDX2 expression) resemble GC and should be evaluated similar to cancerous GIM.
Assuntos
Fator de Transcrição CDX2 , Infecções por Helicobacter , Helicobacter pylori , Neoplasias Gástricas , Humanos , Antígenos de Bactérias/genética , Proteínas de Bactérias/genética , Fator de Transcrição CDX2/genética , Genótipo , Infecções por Helicobacter/complicações , Infecções por Helicobacter/genética , Helicobacter pylori/genética , Metaplasia/genética , Metaplasia/complicações , Neoplasias Gástricas/genética , Neoplasias Gástricas/metabolismoRESUMO
Although many strategies have been reported for modified poly(p-phenylene benzobisoxazole) (PBO) fiber surfaces, the absence of approaches with the potential of applications in industries limits the further applications of the fibers in a wide field. Herein, PBO fibers are modified by heat treatment combined with corona discharge treatment, which is a continuous industrialized method. Then, the surface morphology, wettability, orientation, and crystallinity of the PBO fibers are characterized in detail. Systematic experiments demonstrate that the high thermal treatment can improve the orientation and crystallization degree of the fibers, as well as the degradation resistance. In addition, owing to the synergistic mechanism of ozone and high-frequency shock, the corona discharge treatment increases the contents of O and N elements on the surfaces, which improves the superficial properties of the fibers. Based on the modification of PBO fibers, the inter-laminar shear strength between the fiber and the resin for the composite increases to 94.8%, and the tensile strength of the composite increases to 29.2%, compared to those using untreated fibers. In general, the proposed modification strategy not only easily improves the surface properties and the mechanical properties of composites but also can be used with great potential in industrial production.