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61.
Daud NH Kariwa H Tanikawa Y Nakamura I Seto T Miyashita D Yoshii K Nakauchi M Yoshimatsu K Arikawa J Takashima I 《Microbiology and immunology》2007,51(11):1081-1090
Hokkaido virus (HOKV) is a member of the genus Hantavirus, in the family Bunyaviridae. To investigate HOKV infection in the host Myodes rufocanus, the grey red-backed vole, 199 animals were captured at Tobetsu (October 2004 and July 2005) and Nakagawa (October 2004) in Hokkaido, Japan, for detection of antibody, antigen, and viral RNA. In the surveys in Tobetsu (2004) and Nakagawa (2004), seropositive animals were detected at a frequency of 6.0% (5/84) and 10.4% (5/48), respectively. No seropositive animals were detected in Tobetsu in 2005. Seroprevalence in males in Tobetsu and Nakagawa in 2004 was 25% (1/4) and 45.5% (5/11), respectively, which was higher than in females, at 5.0% (4/80) and 0% (0/37), respectively (P<0.01). These results suggest that male animals play an important role in the maintenance of HOKV in M. rufocanus. Two females were seronegative but viral RNA-positive, indicating that these animals had acute infections before antibody was produced. Another five infected animals in Nakagawa were all male and had high levels of antibodies and viral RNA, suggesting that they had persistent infections. Viral RNA copies in organs of infected animals in Nakagawa were quantified by real-time polymerase chain reaction. Two acutely infected animals had > or = 10 times the number of RNA copies in their lungs compared to those of persistently infected animals. In most cases, lungs or spleen had the highest RNA copy number, regardless of infection status. 相似文献
62.
Watanabe S Pack SP Saleh AA Annaluru N Kodaki T Makino K 《Bioscience, biotechnology, and biochemistry》2007,71(5):1365-1369
We focused on the effects of a mutation of xylose reductase from Pichia stipitis (PsXR) on xylose-to-ethanol fermentation using recombinant Saccharomyces cerevisiae transformed with PsXR and PsXDH (xylitol dehydrogenase from P. stipitis) genes. Based on inherent NADH-preferring XR and several site-directed mutagenetic studies using other aldo-keto reductase enzymes, we designed several single PsXR mutants. K270R showing decreased NADPH-preferring activity without a change in NADH-preferring activity was found to be a potent mutant. Strain Y-K270R transformed with K270R PsXR and wild-type PsXDH showed a 31% decrease in unfavorable xylitol excretion with 5.1% increased ethanol production as compared to the control in the fermentation of 15 g l(-1) xylose and 5 g l(-1) glucose. 相似文献
63.
Karawita R Senevirathne M Athukorala Y Affan A Lee YJ Kim SK Lee JB Jeon YJ 《Marine biotechnology (New York, N.Y.)》2007,9(4):479-490
The enzymatic extracts from seven species of microalgae (Pediastrum duplex, Dactylococcopsis fascicularis, Halochlorococcum porphyrae, Oltmannsiellopsis unicellularis, Achnanthes
longipes, Navicula sp. and Amphora coffeaeformis) collected from three habitats (freshwater, tidal pool, and coastal benthic) at Jeju Island in Korea were investigated for
their antioxidant activity. Of the extracts tested, the AMG 300 L (an exo 1, 4-α-d-glucosidase) extract of P. duplex, the Viscozyme extract of Navicula sp., and the Celluclast extract of A. longipes provided the most potential as antioxidants. Meanwhile, the Termamyl extract of P. duplex in an H2O2 scavenging assay exhibited an approximate 60% scavenging effect. In this study, we report that the DNA damage inhibitory
effects of P. duplex (Termamyl extract) and D. fascicularis (Kojizyme extract) were nearly 80% and 69% respectively at a concentration of 100 μg/ml. Thus, it is suggested that the microalgae
tested in this study yield promising DNA damage inhibitory properties on mouse lymphoma L 5178 cells that are treated with
H2O2. Therefore, microalgae such as P. duplex may be an excellent source of naturally occurring antioxidant compounds with potent DNA damage inhibition potential. 相似文献
64.
Raja Noor Zaliha Raja Abd Rahman Thean Chor Leow Abu Bakar Salleh Mahiran Basri 《BMC microbiology》2007,7(1):77
Background
Thermophilic Bacillus strains of phylogenetic Bacillus rRNA group 5 were described as a new genus Geobacillus. Their geographical distribution included oilfields, hay compost, hydrothermal vent or soils. The members from the genus Geobacillus have a growth temperatures ranging from 35 to 78°C and contained iso-branched saturated fatty acids (iso-15:0, iso-16:0 and iso-17:0) as the major fatty acids. The members of Geobacillus have similarity in their 16S rRNA gene sequences (96.5–99.2%). Thermophiles harboring intrinsically stable enzymes are suitable for industrial applications. The quest for intrinsically thermostable lipases from thermophiles is a prominent task due to the laborious processes via genetic modification. 相似文献65.
66.
Jong-Min Lee Kyung-Hee Kim Aram Shin Michael?J. Chao Kawther Abu?Elneel Tammy Gillis Jayalakshmi?Srinidhi Mysore Julia?A. Kaye Hengameh Zahed Ian?H. Kratter Aaron?C. Daub Steven Finkbeiner Hong Li Jared?C. Roach Nathan Goodman Leroy Hood Richard?H. Myers Marcy?E. MacDonald James?F. Gusella 《American journal of human genetics》2015,97(3):435-444
Huntington disease (HD) reflects the dominant consequences of a CAG-repeat expansion in HTT. Analysis of common SNP-based haplotypes has revealed that most European HD subjects have distinguishable HTT haplotypes on their normal and disease chromosomes and that ∼50% of the latter share the same major HD haplotype. We reasoned that sequence-level investigation of this founder haplotype could provide significant insights into the history of HD and valuable information for gene-targeting approaches. Consequently, we performed whole-genome sequencing of HD and control subjects from four independent families in whom the major European HD haplotype segregates with the disease. Analysis of the full-sequence-based HTT haplotype indicated that these four families share a common ancestor sufficiently distant to have permitted the accumulation of family-specific variants. Confirmation of new CAG-expansion mutations on this haplotype suggests that unlike most founders of human disease, the common ancestor of HD-affected families with the major haplotype most likely did not have HD. Further, availability of the full sequence data validated the use of SNP imputation to predict the optimal variants for capturing heterozygosity in personalized allele-specific gene-silencing approaches. As few as ten SNPs are capable of revealing heterozygosity in more than 97% of European HD subjects. Extension of allele-specific silencing strategies to the few remaining homozygous individuals is likely to be achievable through additional known SNPs and discovery of private variants by complete sequencing of HTT. These data suggest that the current development of gene-based targeting for HD could be extended to personalized allele-specific approaches in essentially all HD individuals of European ancestry. 相似文献
67.
Raju Dash Mir Muhammad Nasir Uddin S.M. Zahid Hosen Zahed Bin Rahim Abu Mansur Dinar Mohammad Shah Hafez Kabir Ramiz Ahmed Sultan Ashekul Islam Md Kamrul Hossain 《Bioinformation》2015,11(12):543-549
Cyclooxygenase-2 (COX-2) catalyzed synthesis of prostaglandin E2 and it associates with tumor growth, infiltration, and metastasis
in preclinical experiments. Known inhibitors against COX-2 exhibit toxicity. Therefore, it is of interest to screen natural compounds
like flavanoids against COX-2. Molecular docking using 12 known flavanoids against COX-2 by FlexX and of ArgusLab were
performed. All compounds showed a favourable binding energy of >-10 KJ/mol in FlexX and > -8 kcal/mol in ArgusLab.
However, this data requires in vitro and in vivo verification for further consideration. 相似文献
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