Effect of calcium oxide on chromium solidification during the melting of hazardous waste incineration fly ash.

Thermal treatment technology considerably affects the harmlessness of fly ash (FA), but highly toxic heavy metals, such as Cr, attract considerable attention. In this study, we investigated the influence of CaO dosage at 600°C-1200 °C on the curing effect of Cr during FA thermal treatment based on the combination effect of CaO. Static, dynamic, and continuous sequential leachings were performed for the sintered products. Results showed that the leaching concentration of Cr decreased by approximately 91% when CaO dosage was 8.57%, and the difference in the residual state was the main reason for the difference in the leaching behavior of Cr. The proportion of the residual state in the sintered products increased from 35.16% to 64.01%. The transition between Cr2O3, Cr5O12, and CaCr2O4 is the fundamental reason for the leaching behavior of Cr and the change in the residual state. This study provides a scientific basis for preventing and controlling heavy metal pollution and optimizing environmental supervision in the FA thermal treatment process.

p27(kip1) upregulated by hnRNPC1/2 antagonizes CagA (a virulence factor of Helicobacter pylori)-mediated pathogenesis.

BACKGROUND AND AIMS: Infection by Helicobacter pylori is one of the major contributing factors of chronic active gastritis and peptic ulcer and is closely associated with the occurrence and progression of gastric cancer. CagA protein is a major virulence factor of H. pylori that interacts with SHP-2, a true oncogene, to interfere with cellular signaling pathways; CagA also plays a crucial role in promoting the carcinogenesis of gastric epithelial cells. However, currently, the molecular mechanisms of gastric epithelial cells that antagonize CagA pathogenesis remain inconclusive. METHODS: We showed that AGS gastric cancer cells transfected with CagA exhibited the inhibition of proliferation and increased activity of caspase 3/7 using two-dimensional gel electrophoresis and secondary mass spectrometry (MS/MS). RESULTS: It was found that the AGS gastric cancer cells stably expressing CagA displayed significantly increased the expression of 16 proteins, including hnRNPC1/2. Further analysis revealed that hnRNPC1/2 significantly boosted the expression of the p27(kip1) protein. CONCLUSION: Our data suggested that hnRNPC1/2 upregulates p27(kip1) expression and the subsequent suppression of cell proliferation and induction of apoptosis, thereby providing an important mechanism whereby gastric epithelial cells antagonize CagA-mediated pathogenesis.

Correlation of the occurrence of YMDD mutations with HBV genotypes, HBV-DNA levels, and HBeAg status in Chinese patients with chronic hepatitis B during lamivudine treatment.

BACKGROUND: Continuous lamivudine therapy is associated with high rates of YMDD mutations, which are the main causes of drug resistance. The current study explores the association of the emergence of YMDD mutations with pretherapy HBV genotype, HBV-DNA levels, HBeAg status, and serum alanine aminotransferase (ALT) levels in Chinese patients receiving lamivudine therapy for chronic hepatitis B. METHODS: A total of 319 chronic hepatitis B patients who received lamivudine therapy for more than a year were enrolled in this study. YMDD mutations, HBV genotype, HBV-DNA levels, HBeAg status, and ALT levels were determined prior to their lamivudine treatment and every three months for a year of this therapy. RESULTS: Among the 319 patients, 137 (42.95%) were infected with genotype B and 182 (57.05%) with genotype C. Up to 94 patients (29.47%) developed YMDD mutations within one year of lamivudine therapy. Furthermore, 50 patients with HBV genotype B and 44 patients with genotype C developed YMDD mutations (36.50% vs 24.18%, P<0.05). Logistic regression analysis showed that pretherapy HBV genotype, HBV-DNA levels, and HBeAg status are independent factors for the emergence of YMDD mutations (HBV genotype: OR=2.159, 95% CI 1.291-3.609, P=0.003; HBV-DNA: OR=1.653, 95% CI 1.231-2.218, P=0.001; HBeAg: OR=2.021, 95% CI 1.201-3.399, P=0.008). CONCLUSIONS: HBV genotype, HBV-DNA levels, and HBeAg status at baseline are the independent factors associated with the emergence of YMDD mutations among Chinese patients receiving lamivudine therapy for chronic hepatitis B. These findings are helpful to the development of therapeutic strategies for these patients.

[Evaluation of aminoglycoside resistance phenotypes and genotyping of acetyltransferase in Escherichia coli].

OBJECTIVE: To investigate the prevalence of aminoglycoside resistance and genotyping of acetyltransferase in Escherichia coli. METHODS: Resistance phenotypes to 12 antibiotics of 44 Escherichia coli isolates were analyzed using agar dilution method and 3 aminoglycoside resistance genes aac(3)-I, II and aac(6')-I were determined by PCR method. RESULTS: In 44 clinical isolates, the occurrence of ESBLs was 45.45%, resistance rates were discrepant for amikacin (18.18%), gentamicin (56.82%) and tobramycin (61.36%), the prevalence of phenotype TG (tobramycin and gentamicin) indicative of aac(3)-II production and TGA (tobramycin, gentamicin and amikacin) indicative of aac(6')-I production were 36.36% and 18.18%, respectively. The most common aminoglycoside resistance genotype of acetyltransferase was aac(3)-II (52.27%) and aac(6')-I was lower (29.55%), but no aac(3)-I was detected. CONCLUSION: At least 2 acetyltransferase genes exist in this area i.e. aac(3)-II and aac(6')-I.