A novel spherical carbon

We developed a novel spherical carbon material. The spherical carbon is composed of a high density of carbon nanotubes or nanofilaments, and includes an oxidized diamond particle as a core. Syntheses of this carbon in high volume with high selectivity may be possible. It is expected that this carbon will be useful as a catalyst material for fuel cells, electric double-layer capacitors, etc.     

Congener-specific carbon isotopic analysis of technical PCB and PCN mixtures using two-dimensional gas chromatography-isotope ratio mass spectrometry

Analysis of stable carbon isotope fractionation is a useful method to study the sources and fate of anthropogenic organic contaminants such as polychlorinated biphenyls (PCBs) in the environment. To evaluate the utility of carbon isotopes, determination of isotopic ratios of 13C/12C in source materials, for example, technical PCB preparations, is needed. In this study, we determined delta13C values of 31 chlorobiphenyl (CB) congeners in 18 technical PCB preparations and 15 chloronaphthalene (CN) congeners in 6 polychlorinated naphthalene preparations using two-dimensional gas chromatography-combustion furnace-isotope ratio mass spectrometry (2DGC-C-IRMS). Development of 2DGC-IRMS enabled improved resolution and sensitivity of compound-specific carbon isotope analysis (CSIA) of CB or CN congeners. Delta13C values of PCB congeners ranged from -34.4 (Delors) to -22.0/1000 (Sovol). Analogous PCB preparations with similar chlorine content, but different geographical origin, had different delta13C values. PCB preparations from Eastern European countries--Delors, Sovol, Trichlorodiphenyl, and Chlorofen--had distinct delta13C values. PCB mixtures showed increased 13C depletion with increasing chlorine content. Delta13C values for individual CB congeners varied depending on the degree of chlorination in technical mixtures. Delta13C values of CN congeners in Halowaxes ranged from -26.3 to -21.7/1000 and these values are within the ranges observed for PCBs. This study establishes the range of delta13C values in technical PCB and PCN preparations, which may prove to be useful in the determination of sources of these compounds in the environment. This is the first study to employ 2DGC-IRMS analysis of delta13C values in technical PCB and PCN preparations.     

Screening the p53 status of human cell lines using a yeast functional assay

We have screened the p53 status of 156 human cell lines, including 142 tumor cell lines from 27 different tumor types and 14 cell lines from normal tissues by using functional analysis of separated alleles in yeast. This assay enables us to score wild-type p53 expression on the basis of the ability of expressed p53 to transactivate the reporter gene HIS3 via the p53-responsive GAL1 promotor in Saccharomyces cerevisiae. Of 142 tumor cell lines, at least 104 lines (73.2%) were found to express the mutated p53 gene: 94 lines (66.2%) were mutated in both alleles, three lines (2.1%) were heterozygous, and no p53 cDNA was amplified from seven lines (4.9%). Of the 14 cell lines originating from normal tissues, all the transformed or immortalized cell lines expressed mutant p53 only. Yeast cells expressing mutant p53 derived from 94 cell lines were analyzed for temperature-sensitive growth. p53 cDNA from eight cell lines showed p53-dependent temperature-sensitive growth, growing at 30 degrees C but not at 37 degrees C. Four temperature-sensitive p53 mutations were isolated: CAT-->CGT at codon 214 (H214R), TAC-->TGC at codon 234 (Y234C), GTG-->ATG at codon 272 (V272M), and GAG-->AAG (E285K). Functionally wild-type p53 was detected in 38 tumor cell lines (26.8%) and all of the diploid fibroblasts at early and late population doubling levels. These results strongly support the previous findings that p53 inactivation is one of the most frequent genetic events that occurs during carcinogenesis and immortalization.     

Patterning cultured cells by visible light illumination with photosensitizers

We showed that PC12 cells and 3T3 cells cultured in dishes were killed by illumination with visible white light from a halogen lamp at 7 x 10(4) lx for 5 min in the presence of either 10 microM hematoporphyrin or 2 microM methylene blue as a photosensitizer. This simple technique, based on the photodynamic reaction via generation of reactive oxygen species can be applicable for patterning cultured cells.     

Analysis of the DNA sequence of a 15,500 bp fragment near the left telomere of chromosome XV from Saccharomyces cerevisiae reveals a putative sugar transporter,a carboxypeptidase homologue and two new open reading frames

We report the sequence of a 15·5 kb DNA segment located near the left telomere of chromosome XV of Saccharomyces cerevisiae. The sequence contains nine open reading frames (ORFs) longer than 300 bp. Three of them are internal to other ones. One corresponds to the gene LGT3 that encodes a putative sugar transporter. Three adjacent ORFs were separated by two stop codons in frame. These ORFs presented homology with the gene CPS1 that encodes carboxypeptidase S. The stop codons were not found in the same sequence derived from another yeast strain. Two other ORFs without significant homology in databases were also found. One of them, O0420, is very rich in serine and threonine and presents a series of repeated or similar amino acid stretches along the sequence. The nucleotide sequence has been deposited in the EMBL data library under Accession Number X89715.     

Impact of Obesity-Induced Inflammation on Cardiovascular Diseases (CVD)

Overweight and obesity are key risk factors of cardiovascular disease (CVD). Obesity is currently presented as a pro-inflammatory state with an expansion in the outflow of inflammatory cytokines, such as interleukin-6 (IL-6) and tumor necrosis factor-alpha (TNF-α), alongside the expanded emission of leptin. The present review aimed to evaluate the relationship between obesity and inflammation and their impacts on the development of cardiovascular disease. A literature search was conducted by employing three academic databases, namely PubMed (Medline), Scopus (EMBASE), and the Cumulative Index to Nursing and Allied Health Literature (CINAHL). The search presented 786 items, and by inclusion and exclusion filterers, 59 works were considered for final review. The Newcastle–Ottawa Scale (NOS) method was adopted to conduct quality assessment; 19 papers were further selected based on the quality score. Obesity-related inflammation leads to a low-grade inflammatory state in organisms by upregulating pro-inflammatory markers and downregulating anti-inflammatory cytokines, thereby contributing to cardiovascular disease pathogenesis. Because of inflammatory and infectious symptoms, adipocytes appear to instigate articulation and discharge a few intense stage reactants and carriers of inflammation. Obesity and inflammatory markers are strongly associated, and are important factors in the development of CVD. Hence, weight management can help prevent cardiovascular risks and poor outcomes by inhibiting inflammatory mechanisms.     

Amorphous-silicon-on-glass field emitter arrays

An amorphous-silicon (a-Si) field emitter array (FEA) has been fabricated on a glass substrate and characterized, At first, a 0.3-μm-thick Cr film was deposited on the glass by vacuum evaporation technique and subsequently a 1-μm-thick Si film was deposited on the Cr film by conventional RF sputtering technique with an undoped Si target at room temperature. The sputtered Si film was identified as amorphous from X-ray diffraction patterns and had a resistivity of 3-5 kΩ-cm. The FEA consists of 1-μm-high emitter tips and a gate electrode with 1.8-μm-diameter openings. This a-Si FEA with 5×5 (=25) tips exhibited a threshold voltage of 30 V and an emission current of 2 μA at a gate voltage of 100 V. Structure and emission characteristics are discussed