RESUMO
Aim: The current study aimed to assess the frequency of CDH1 promoter gene hypermethylation in gastric cancer and chronic gastritis and its correlation with clinicopathological aspects. Methods: Methylation-specific PCR was used to detect CDH1 promoter gene hypermethylation in 53 chronic gastritis patients and 40 gastric cancer patients along with normal adjacent tissues. Results: The chronic gastritis group comprised 29 males and 24 females with a mean age of 51.8 ± 12.96 years, and 49.1 % of them were positive for H. pylori infection. The frequency of CDH1 hypermethylation in gastritis lesions was 18.8 %. CDH1 hypermethylation showed a significant correlation with H. pylori infection (p = 0.039), but no significant association was observed with other clinical features. The gastric cancer group consisted of individuals with a mean age of 65.4 ± 10.6, among them, 77.5 % were male and 22.5 % were female, 62.5 % had PT3 tumors, 40 % had PN1 lymph node involvement, and the majority (47.5 %) of samples were obtained from body segment. CDH1 hypermethylation was significantly associated with depth of invasion (p = 0.017) and nodal invasion (p = 0.041) in this group. In both groups, normal adjacent specimens lacked CDH1 hypermethylation, and there was no statistically significant correlation between CDH1 hypermethylation and age at which the tumor was diagnosed, gender, activity level, or tumor location. Conclusion: This study demonstrates that E-cadherin methylation is associated with some characteristics of chronic gastritis and gastric cancer. These findings support previous research indicating that CDH1 hypermethylation may play a significant role in the development of gastric cancer.
RESUMO
In this study, talc-supported nano-galvanic Sn doped nZVI (Talc-nZVI/Sn) bimetallic particles were successfully synthesized and utilized for Cr(VI) remediation. Talc-nZVI/Sn nanoparticles were characterized by FESEM, EDS, FTIR, XRD, zeta potential, and BET analysis. The findings verified the uniform dispersion of nZVI/Sn spherical nanoparticles on talc surface with a size of 30-200 nm, and highest specific surface area of 146.38 m2/g. The formation of numerous nano-galvanic cells between nZVI core and Sn shell enhanced the potential of bimetallic particles in Cr(VI) mitigation. Moreover, batch experiments were carried out to investigate optimum conditions for Cr(VI) elimination and total Cr(VI) removal was achieved in 20 min using Sn/Fe mass ratio of 6/1, the adsorbent dosage of 2 g/L, initial Cr(VI) concentration of 80 mg/L, at the acidic environment (pH = 5) and temperature of 303 K. Besides, co-existing of metallic cations turned out to facilitate the electron transfer from the nano-galvanic couple of NZVI/Sn, and suggested the revolution of bimetallic particles to trimetallic composites. The aging study of the nanocomposite confirmed its constant high activity during 60 days. The removal reaction was well described by the pseudo-second-order kinetic and the modified Langmuir isotherm models. Overall, due to the synergistic galvanic cell effect of nZVI/Sn nanoparticles and full coverage of active sites by Sn layer, Talc-nZVI/6Sn was utilized as a promising nanocomposite for fast and highly efficient Cr(VI) elimination.