ABSTRACT
Developing a novel catalyst with lower noble-metal loading and higher catalytic efficiency is significant for promoting the widespread application of direct alcohol fuel cells (DAFCs). In this work, poly(3,4-ethylenedioxythiophene) (PEDOT) supported the PdSn alloy (PdSn/PEDOT) were simply synthesized and their electrocatalytic performance toward the oxidation of ethylene glycol and ethanol (EGOR and EOR) were investigated in alkaline media, respectively. In comparison with other control catalysts, the optimized Pd4Sn6/PEDOT catalyst exhibits the highest mass activity (7125/4166 mA mgPd-1) and specific activity (26/15 mA cm-2) towards EGOR/EOR. The mass activity of Pd4Sn6/PEDOT for EGOR and EOR are 11.9 and 10.9 times higher than commercial Pd/C, respectively. Moreover, chronoamperometry (CA) and successive cyclic voltammetry (CV) tests show that the CO resistance ability and durability of the Pd4Sn6/PEDOT catalyst were superior to Pd4Sn6, Pd/PEDOT and commercial Pd/C catalysts, which can be attributed to the d-band center of Pd can be effectively downshifted and the interface strain effect between electrons caused by the conjugated structure between PEDOT groups. This work provides an effective strategy for the development of highly efficient anode catalysts of DAFCs.
ABSTRACT
Histone H2B monoubiquitination is a key histone modification that has significant effects on chromatin higher-order structure and gene transcription. Multiple biological processes have been suggested to be tightly related to the dynamics of H2B monoubiquitination. However, a comprehensive understanding of biological roles of H2B monoubiquitination is still poorly understood. In the present study, we developed an efficient tool to disrupt endogenous H2B monoubiquitination levels by using an H2BK120R mutant construct expressed in human cells. Genome-wide microarray analysis of these cells revealed a potential global view of biological functions of H2B monoubiquitination. Bioinformatics analysis of our data demonstrated that while H2B monoubiquitination expectedly affected a number of previously reported biological pathways, we also uncovered the influence of this histone modification on many novel biological processes. Therefore, our work provided valuable information for understanding the role of H2B monoubiquitination and indicated potential directions for its further studies.
Subject(s)
Histones/metabolism , Oligonucleotide Array Sequence Analysis , Ubiquitination , Animals , Cell Differentiation/genetics , Chromatin/metabolism , DNA Damage/genetics , DNA Repair/genetics , Gene Expression Profiling , Gene Expression Regulation , Gene Knockdown Techniques , HEK293 Cells , HeLa Cells , Histones/genetics , Humans , Mice , Mouse Embryonic Stem Cells/cytology , Mutant Proteins/metabolism , Mutation/genetics , Ubiquitin/metabolismABSTRACT
The aim of this study was to establishment of known HPA genotype platelet donor data base and carry out the platelet antigen gene typing and matching in the platelet transfusion so as to prevent the production of the antibody and to avoid the platelet transfusion refractoriness. HPA of the donors and the patients were genotyped by PCR-SSP. The platelet transfusion with the same ABO type and HPA genotypes as the patient was selected and infused if the solid-phase agglutination matching was consistent. The results showed that the distribution of HPA types in Chinese Mudanjiang area had its own characteristics. HPA-15 had the greatest heterozygosity, and then HPA-3. The effective rate was 94.4% if both the HPA types and the ABO types were coincident while the effective rate was 77.8% when only ABO types were coincident. It is concluded that the distribution of HPA types in Chinese Mudanjiang area presents genetic polymorphism. The platelet transfusion with genetic typing and matching of both HPA and ABO types is an effective way to avoid production of the antibody and platelet transfusion refractoriness.
Subject(s)
Antigens, Human Platelet/immunology , Blood Grouping and Crossmatching , Platelet Transfusion/methods , Adolescent , Adult , Antigens, Human Platelet/genetics , Female , Genotype , Humans , Male , Middle Aged , Young AdultABSTRACT
This study was aimed to explore the distribution characteristics of the human platelet antigen (HPA) gene of human platelet donors and its polymorphism in Mudanjiang area of Heilongjiang Province in China, to determine platelet antigen system with clinical significance by judging the rate of incompatibility of HPA, as well as to establish a database of donors' HPA. The genotyping of 154 unrelated platelet donors was performed by means of PCR-SSP. The frequencies of gene and genotype were calculated and compared with that in other areas. The results showed that the genes 1a-17a of HPA-a were all expressed in the 154 healthy and unrelated platelet donors. Only genes 1b, 2b, 3b, 5b, 6b and 15b of HPA-b were expressed while genes 4b, 7b-14b, 16b were not expressed. Among the genotypes, aa homozygosity was predominant and HPA15 had the greatest heterozygosity, while HPA3 had lower heterozygosity. There were 23 combined types of HPA, 5 of them had a rate higher than 10%, and the frequencies of the other 18 were lower than 8%. HPA genotype frequencies showed a good consistency to Hardy-Weinberg equilibrium. It is concluded that the distribution of the allele polymorphism of HPA1-HPA17 in Mudanjiang area has its own characteristics, compared with other areas and some countries, the local HPA genotype database of platelet donors is established in Mudanjiang area, which can provide the matching donors for clinical use with immunological significance.
