Activation of Co-O bond in (110) facet exposed Co3O4 by Cu doping for the boost of propane catalytic oxidation.

Defects engineering in metal oxide is an important avenue for the promotion of VOCs catalytic oxidation. Herein, the influence of crystal facet of Co3O4 is first investigated for the propane oxidation. An intelligent Cu doping is subsequently performed in the most active (110) facet exposed Co3O4 catalyst. The optimized Cu-Co3O4-110-3 catalyst exhibits a prominently enhanced activity with propane conversion rate of 1.9 µmol g-1 s-1 at reaction temperature of 192 °C and the propane mass space velocity of 60,000 mL g-1 h-1, about 2.4 times that of the pristine Co3O4. Systematic experimental characterizations (XAS, EPR, Raman, TPR, XPS, etc.) combined with density functional theory calculations point out that the incorporated Cu could increase the electrophilicity of nearby O atom and implant beneficial defect structures (lattice distortion, coordination unsaturation, abundant oxygen vacancies, etc.), which could significantly activate Co-O bond in Co3O4, leading to the facilitated generation of active oxygen species as well as promoted oxidation ability. This study could set an illuminating paradigm for the boost of the intrinsic oxidation activity by the precise defect construction in Co3O4 catalyst, which will help drive ahead the pursuit of non-precious metal catalyst for VOCs abatement.

An association between overexpression of DNA methyltransferase 3B4 and clear cell renal cell carcinoma.

It is well known that abnormal DNA methylations occur frequently in kidney cancer. However, it remains unclear exactly which types of DNA methyltransferases (DNMT) contribute to the pathologies of kidney cancers. In order to determine the functions of DNA methyltransferase in kidney tumorigenesis on the molecular level, we examined the mRNA expression levels of DNMT1, DNMT3A, DNMT3B, and DNMT3B variants in renal cell carcinoma tissue. Both mRNA and protein levels of DNMT3B4, a splice variant of DNMT3B, were increased in renal cell carcinoma tissue compared with adjacent control tissues. Additionally, Alu elements and long interspersed nuclear elements (LINE-1) were hypomethylated in renal cell carcinoma tissue. Meanwhile, methylation of the promoter for RASSF1A, a tumor suppressor gene, was moderately increased in renal cell carcinoma tissue, while RASSF1A expression was decreased. Thus, our data suggest that the overexpression of DNMT3B4 may play an important role in human kidney tumorigenesis through chromosomal instability and methylation of RASSF1A.

[Expression level of p53 in Tumor Tissue of Patients with Acute Leukemia and Its Clinical Significance].

OBJECTIVE: To study the expression level of p53 in tumor tissue of patients with acute leukemia (AL) and its clinical significance. METHODS: From April 2013 to April 2015, 80 patients with AL in our hospital were chosen as leukemia group, at the same time, 50 patients with non-hematologic diseases were chosen as control group. All the patients were detected by bone marrow smear mean and p53 staining. The positive rate of p53 and staining score were compared between 2 groups. The clinical data of leukemia group were collected, and the correlation of clinical features with p53 expression was analyzed. RESULTS: In the control group, the positive rate of p53 was 6.00%, the staining score was (0.2 ± 0.1); in the leukemia group, the positive rate of p53 was 73.75%, the staining score was (1.9 ± 0.4), the difference was statistically significant (P < 0.05). The expression of p53 significantly correlated with the blood routine indicators, clinical manifestation, multiple infiltration and curative effects (P < 0.05), and the p53 expression not correlated statistically with the sex, age, anamnesis, family history (P > 0.05). CONCLUSION: Compared with the patients with non-hematologic diseases, the expression level of p53 in the AL patients increases significantly, the p53 expression correlates significantly with the blood routine indicators, clinical manifestation and curative effect of the patients.