The Recent Progress of Oxygen Reduction Electrocatalysts Used at Fuel Cell Level.

Proton exchange membrane fuel cells (PEMFCs) are gaining significant interest as an attractive substitute for traditional fuel cells, with higher energy density, lower environmental pollution, and better operation efficiency. However, the cathode reaction, i.e., the oxygen reduction reaction (ORR), is widely proved to be inefficient, and therefore an obstacle to the widespread development of PEMFCs. The requirement for affordable highly-efficient ORR catalysts is extremely urgent to be met, especially at fuel cell level. Unfortunately, most previous reports focus on the ORR performance at rotating disk electrodes (RDE) level instead of membrane electrode assembly (MEA) level, making it harder to evaluate ORR catalysts operating under real vehicle conditions. Obviously, it is extremely necessary to develop an in-depth understanding of the structure-activity relationship of highly-efficient ORR catalysts applied at MEA level. In this work, an overview of the latest advances in ORR catalysts is provided with an emphasis on their performance at MEA level, hoping to cover the novel and systemic insights for innovative and efficient ORR catalyst design and applications in PEMFCs.

A new diphenyl ether derivative from Mirabilis himalaica.

One new compound, himalain A (1), together with 12 known compounds were isolated from Mirabilis himalaica. Their structures were determined by spectroscopic methods, including 2D NMR techniques, and the absolute configuration of the 1,2-diol moiety in 1 was defined through Riguera's method. All isolated compounds were tested for their cytotoxic and antibacterial activities.

[Concentration distribution of metal elements in atmospheric aerosol under different weather conditions in Qingdao Coastal Region].

To know the influence of different weather conditions on the concentration of metal elements in aerosols in the coastal region, total suspended particles (TSP) samples were collected from April to May 2012, and August 2012 to March 2013 in the Qingdao coastal region, and common trace metals were analyzed by using Inductively Coupled Plasma-Mass Spectrometry (ICP-MS) and Inductively Coupled Plasma-Atomic Emission Spectrometry (ICP-AES). The results showed that Al, Ca, Fe, Na, K and Mg were the dominant metal elements in TSP, and the sum of the six elements accounted for 94.2% of the sum of all metals. TSP and metal elements had significant monthly variations, Fe, Al, K, Ca, Mg, Zn, Ba, Mn, Ti, Sr and Li had the highest concentration in November and January, while Be, Sc, Co, Ni and Cr showed the highest value in January. Na had the highest concentration in August, November and February, and the lowest in December. Pb had the highest concentration in January and February, and the lowest in August and December. Enrichment factors indicated that Be, Co, Al, Ca, Fe, K, Mg, Mn, Sr and Ti were mainly affected by natural sources; Li, Cr, Ni, Zn, Ba and Na were affected by natural sources and part of anthropogenic sources; Pb was mainly from anthropogenic sources. Different weather conditions had great impact on TSP and metal elements concentrations, all the measured metals had the highest concentrations in smog except Ti. Compared with the sunny day, the concentration of atmospheric particulate Ti decreased, while the other elements increased by 1 to 4 times in smog. Li, Be, Cr, Ni, Al, Fe, Mg and Mn had little variation in concentration in foggy day, and the concentration of Pb and Na increased considerably. The concentration of Co, Ca and Ti reduced obviously in fog. Except for Cr, Co and Ti, the other elements increased by 1 to 3 times in haze. Most of the elements had the minimal enrichment factors in sunny day, while the other had the maximal enrichment factor in foggy day. Enrichment factors of Ni, Zn, Ba, K, Na, Pb and Sr varied in the order of sunny day < haze day < smog day

[Preliminary study on the association of chemokine RANTES gene polymorphisms with HIV-1 infection in Chinese Han population].

OBJECTIVE: To detect the single nucleotide polymorphism (SNP) of chemokine regulated upon activation, normal T cell expressed and secreted (RANTES) promoter and first intron of asymptomatic, human immunodeficiency virus 1 (HIV-1) infected individuals of in Han Chinese and evaluate the influence on HIV-1 infection by variants. METHODS: Case-control study was adopted, Genotypes of RANTES promoter -403 and -28 from 538 samples and RANTES first intron In1.1 from 300 samples of Han Chinese were detected by DNA sequencing or by polymerase chain reaction-restriction fragment length polymorphism. RESULTS: There were six genotypes of RANTES promoter -403 and -28 found in Han Chinese group. The distribution of genotypes was AC/AC 12.4%, AC/AG 3.5%, AC/GC 29.2%, AG/GC 10.9%, GC/GC 42.1%, AG/AG 1.5%. The haplotypes was GC 62.7%, AC 28.7%, AG 8.6%. Compared with AC/AC, Odd ratio (OR) of RANTES genotypes AC/AG, AC/GC, AG/GC, GC/GC was associated with weaker reduced susceptibility to HIV-1 infection. However, there were no significant contents of the allele frequencies between people living with HIV-1 and healthy individuals. The distribution of RANTES In1.1 alleles were T/T 71.0%, C/T 19.9%, C/C 9.1% and haplotypes were RANTES In1.1T 81%, In1.1C 19%, respectively; There were significant differences of RANTES In1.1 between people with HIV-1 infection and healthy individuals in males. The In1.1C-bearing genotypes would increase susceptibility to HIV-1 infection but no significant differences in females were found. Strong linkage disequilibrium was observed between all of the three RANTES SNPs. CONCLUSION: The two -403A/G, -28C/G variants in RANTES promoter region and intron In1.1 T/C mutation genotype were found to be associated with the genetic susceptibility to HIV-1 infection among the Han Chinese. However, the In1.1C allele or its haplotypes in RANTES intron 1 displayed a stronger dominant association with HIV-1 infection in males.

[Distribution of HIV-1 coreceptor CX3CR1 allelic polymorphisms in general population, HIV-1 high-risk group and HIV-1 carriers of Chinese indigenous Han and Uygur people].

OBJECTIVE: To investigate the V249I and T280M allelic polymorphisms of human immunodeficiency virus (HIV) coreceptor CX3CR1 in HIV-1 infected and uninfected population of Chinese indigenous Han and Uygur people and to probe the association between I249-M280 haplotype and HIV-1 susceptibility as well as AIDS progression. METHODS: Genomic DNA of 223 Uygur subjects and 316 Han subjects were purified from PBMC. I249 and M280 allelic frequencies were identified by polymerase chain reaction (PCR)/nest polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) analysis. All data were tested by chi(2) or u statistics analysis. RESULTS: Allelic frequencies of I249 and M280 were 16.1% and 13.3% in Uygur people, and 3.3% and 2.4% in Han people. No obvious difference existed between three groups of either ethnic group. However the allelic frequencies of HIV infected population were higher than those of general population, and those of general population higher than those of HIV-1 high-risk group. There was a strong linkage between I249 and M280 (P almost zero). CONCLUSIONS: I249 mutation was the sine qua non of M280 mutation, and most I249 alleles were accompanied by M280. The frequency of I249-M280 haplotype in Uygur population (13.3%) was adjacent to Caucasian people (15.8%), and that of I249-T280 haplotype (2.8%) was obviously lower than Caucasian people (12.5%); while both of them in Han people were much lower (0.9% and 2.4%). I249-M280 haplotype could accelerate AIDS progression according to Faure et al, while might be associated with HIV-1 susceptibility.

[Polymorphism of CXCR4 coding region of human immunodeficiency virus-1 in Chinese Han people].

OBJECTIVE: To study the polymorphism of human immunodeficiency virus (HIV)-1 coreceptor CXCR4 in Chinese Han ethnic group for AIDS prevention and treatment. METHODS: Totally 48 individuals were enrolled into the study. CXCR4 (cDNA No-AF147204) was cloned by PCR amplification using 2 pairs of primers, then sequenced using sequencing primers. The results of the same sequencing primers were analyzed by DNAstar software to find and identify single nucleotide polymorphism (SNP) sites. RESULTS: Totally 7 SNPs were found in the coding region of CXCR4, among them 3 were synonymous mutation (C-->T at loci 129, 426 and 968), 3 were missense mutation (C-->T at locus 38, A-->T at locus 90, and A-->C at locus 712) and 1 was stop mutation (C-->T at 106, which converted the codon for glutamic acid into stop codon). CONCLUSIONS: The polymorphism of CXCR4 coding region in Chinese Han is probably different from that of the other ethnic groups. Six of the 7 SNPs were discovered for the first time. Their influences on AIDS progression are worthy of studying.

Population survey of CCR5 delta32, CCR5 m303, CCR2b 64I, and SDF1 3'A allele frequencies in indigenous Chinese healthy individuals, and in HIV-1-infected and HIV-1-uninfected individuals in HIV-1 risk groups.

The aim of this study is to determine in indigenous Chinese ethnic groups the frequencies of the chemokine (SDF1 3'A) and chemokine receptors (CCR5 delta32, CCR5 m303, and CCR2b 64I) HIV-1/AIDS restriction alleles. The study includes two cohorts; the first comprised 3165 indigenous healthy subjects representing eight ethnic groups: Han (n = 1406), Uygur (n = 316), Mongolia (n = 134), Hui (n = 386), Tibetan (n = 330), Zhuang (n = 378), Dai (n = 101), and Jingbo (n =114). The second cohort consisted of 330 HIV-1-infected (86 subjects infected by sexual transmission and 198 subjects infected by HIV-1-contaminated blood or by sharing injection equipment; the remaining 46 subjects said nothing about HIV-1 transmission) and 474 HIV-1-uninfected Han Chinese belonging to one of two HIV-1 high-risk groups: intravenous drug users (n = 215) and individuals with sexually transmitted diseases (n = 259). Genotypes for the four genes were obtained using PCR (CCR5 delta32) or PCR-restriction fragment length polymorphism. Randomly selected amplified PCR products were further confirmed by direct DNA sequencing. The variant allele frequencies were determined to be 0% to 3.48% for CCR5 delta32, 0% for CCR5 m303, 16.23% to 28.79% for CCR2b 64I, and 17.70% to 27.76% for SDF1 3'A in Chinese healthy individuals from eight ethnic groups. These findings show that allele frequencies differ among the eight Chinese ethnic groups for CCR5 delta32, CCR2b 64I, and SDF1 3'A and that the CCR5 m303 and CCR5 delta32 mutant alleles were absent or infrequent in Chinese, which may be helpful for studies of specific anti-HIV-1 vaccine trials and coreceptor inhibitor drug targets in Chinese populations. Furthermore, we observed no significant differences in allele or genotypic frequencies between HIV-1-infected and HIV-1-uninfected groups from the Han ethnic group. Our finding is the first reporting that there is likely no effect of the examined polymorphisms in our study on HIV-1 transmission in the Chinese Han population, However, the genetic effects of these and other AIDS-modifying polymorphisms on the pathogenesis and clinical outcome of HIV-1/AIDS diseases is under investigation in Chinese populations.

[Single nucleotide polymorphism loci of HIV-1 coreceptor CCR5 gene in Chinese Han people].

OBJECTIVE: To investigate the single nucleotide polymorphism(SNP) loci of HIV-1 coreceptor CCR5 gene in Chinese Han people. METHODS: The coding region of CCR5 was amplified using 2 pairs of primers and the PCR products of all 42 healthy subjects were sequenced by 4 different primers. The results of sequencing were analyzed by DNAstar in search of SNP loci. RESULTS: Six SNP loci were discovered in the coding region of CCR5, among them four SNPs, i.e. 184A-->G, 503G-->T, 688G-->A and 999G-->T, cause amino acids changes and two SNPs are nonsense mutations. One cytosine deletion at the 894nt results in frame shift mutation and prematured termination. 184A-->G, 503G-->T and 999G-->T were found in Chinese Han people for the first time. The allelic frequencies of mutant 184G, 503T and 999T alleles were 1.1%, 21.1% and 10.0% in healthy Hans, respectively. The population distribution of G503T markedly deviated from Hardy-Weinberg equilibrium. CONCLUSION: The SNP loci in the coding region of CCR5 in Chinese Han people has its own characteristics, which is not consistent with those of Japanese and obviously different from those of Caucasian and African.

[Distribution of the HIV/AIDS associated CCR5Delta32,CCR2b-64I,SDF1-3'A allelesin Chinese Dai and Chingpaw populations from Dehong autonomous prefecture of Yunnan Province].

The purpose of the work is to investigate the frequencies and polymorphisms of HIV-1 resistant CCR5delta32,CCR2b-64I,SDF1-3'A alleles in Chinese Dai and Chingpaw populations. Whole blood samples from 101 Dai subjects and 113 Chingpaw were collected randomly and their genomic DNA were extracted with QIAgen Blood Kits. Allelic frequencies were identified by PCR-RFLP analysis. Allelic polymorphisms in Dai population or Chingpaw population and both sexes in the samples were analyzed by chi(2) test. The frequencies of CCR5delta32,CCR2b-64I,SDF1-3'A alleles in Dai population were 0.0000,0.2130,0.2030, respectively. The frequencies of CCR5delta32,CCR2b-64I,SDF1-3'A alleles in Chingpaw population were 0.000, 0.1637, 0.1770, respectively. Distributions of the CCR2b-64I,SDF1-3'A alleles among the both populations were in accordance with Hardy-Weinberg equilibrium. No statistical difference was found in the allelic frequencies of both CCR2b-64I and SDF1-3'A between male and female individuals. The frequencies of CCR5delta32,CCR2b-64I alleles in Chinese Dai and Chingpaw populations are similar to that in Chinese Han population, while the frequency of SDF1-3'A allele in Chinese Dai and Chingpaw populations are lower in contrast to that in Chinese Han population. The genotyping and polymorphism of CCR5delta32,CCR2b-64I,SDF1-3'A alleles in Chinese Dai and Chingpaw populations of Yunnan Province are the first time studied in China. The significance of the three mutant alleles conferring genetic resistance to HIV-1 and AIDS progression remains to be clarified.

Antitumor activities of human autologous cytokine-induced killer (CIK) cells against hepatocellular carcinoma cells in vitro and in vivo.

AIM: To characterize the anticancer function of cytokine-induced killer cells (CIK) and develop an adoptive immunotherapy for the patients with primary hepatocellular carcinoma (HCC), we evaluated the proliferation rate, phenotype and the antitumor activity of human CIK cells from healthy donors and HCC patients in vitro and in vivo. METHODS: Peripheral blood mononuclear cells (PBMC) from healthy donors and patients with primary HCC were incubated in vitro and induced into CIK cells in the presence of various cytokines such as interferon-gamma (IFN-gamma), interleukin-1 (IL-1), IL-2 and monoclonal antibody (mAb) against CD3. The phenotype and characterization of CIK cells were identified by flow cytometric analysis. The cytotoxicity of CIK cells was determined by (51)Cr release assay. RESULTS: The CIK cells were shown to be a heterogeneous population with different cellular phenotypes. The percentage of CD3+/CD56+ positive cells, the dominant effector cells, in total CIK cells from healthy donors and HCC patients, significantly increased from 0.1-0.13% at day 0 to 19.0-20.5% at day 21 incubation, which suggested that the CD3+ CD56+ positive cells proliferated faster than other cell populations of CIK cells in the protocol used in this study. After 28 day in vitro incubation, the CIK cells from patients with HCC and healthy donors increased by more than 300-fold and 500-fold in proliferation cell number, respectively. CIK cells originated from HCC patients possessed a higher in vitro antitumor cytotoxic activity on autologous HCC cells than the autologous lymphokine-activated killer (LAK) cells and PBMC cells. In in vivo animal experiment, CIK cells had stronger effects on the inhibition of tumor growth in Balb/c nude mice bearing BEL-7402-producing tumor than LAK cells (mean inhibitory rate, 84.7% vs 52.8%, P<0.05) or PBMC (mean inhibitory rate, 84.7% vs 37.1%, P<0.01). CONCLUSION: Autologous CIK cells are of highly efficient cytotoxic effector cells against primary hepatocellular carcinoma cells and might serve as an alternative adoptive therapeutic strategy for HCC patients.