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101.
Ikuta K Yamada T Shimomura T Kuratsune H Kawahara R Ikawa S Ohnishi E Sokawa Y Fukushi H Hirai K Watanabe Y Kurata T Kitani T Sairenji T 《Microbes and infection / Institut Pasteur》2003,5(12):1096-1102
To investigate the association of viral infections with chronic fatigue syndrome (CFS), we assayed 2', 5'-oligoadenylate synthetase (2-5AS) activities in peripheral blood mononuclear cells from CFS patients in Japan. These patients were diagnosed in two hospitals, H1 and H2, located in different areas of the country. The activities were detected in 19 (86%) and 7 (32%) of each of the 22 patients in H1 and H2, respectively, while they were detected in only four (11%) out of the 38 healthy controls. IFN-alpha was similarly detected in a few CFS patients and healthy controls. We also assayed the antibody titers against Epstein-Barr virus (EBV) and Coxiella burnetii in these patients. The EBV anti-EA-IgG antibodies were detected in two (9%) and seven (32%) of each of the 22 patients in H1 and H2, respectively. Anti-C. burnetii IgG antibodies were detected in six (27%) out of 22 patients in H1 but not in 22 patients in H2, while they were detected in one (11%) of the nine healthy controls. Some CFS patients may be associated with EBV or C. burnetii infection. There were some statistical correlations between the 2-5AS activities and antibody titers of EA-IgG (P < 0.05, Student's t-test) but not to the antibody titers of C. burnetii. The up-regulation of 2-5AS activities suggests immunological dysfunctions with some virus infections in the CFS patients. Our results indicate that 2-5AS activities are useful for a diagnostic marker of CFS and for exploring the complicated pathogenesis of CFS. 相似文献
102.
A homologue of the ferric uptake regulator gene (fur) was isolated from Moraxella bovis by degenerate polymerase chain reaction and cloning. Fur protein of M. bovis exhibited 72.1% amino acid identity with Acinetobacter calcoaceticus Fur. Western blot analysis showed a decrease of Fur expression in response to sufficient-iron conditions compared with deficient-iron conditions. An electrophoretic mobility-shift assay indicated that Fur protein binds to DNA fragments containing a putative Fur-box derived from the upstream region of the M. bovis fur gene. Fur of M. bovis may regulate the expression of iron transport systems in response to iron limitation in the environment. 相似文献
103.
Saccharomyces servazzii plays a crucial role in the making of Japanese radish pickles. To make more flavorsome pickles, we sought to generate trifluoroleucine-resistant mutants of S. servazzii. The three resulting mutants could be classified into two types: one that produces more isoamyl alcohol than the parental strain, and one that produces less. The first type has been well documented in Saccharomyces cerevisiae but the latter appears to be novel and has been characterized as such. 相似文献
104.
New double stimuli-responsive poly(alpha-N-substituted gamma-glutamine) has been developed, which was synthesized by the reaction of poly(gamma-glutamic acid) with amino alcohols. Appropriate combinations of the amino alcohols provided the biodegradable poly(amino acid) exhibiting a sharp lower critical solution temperature (LCST) in water. Furthermore, the phase transition temperature was highly sensitive to pH changes. 相似文献
105.
Obayashi E Shimizu H Park SY Shoun H Shiro Y 《Journal of inorganic biochemistry》2000,82(1-4):103-111
Threonine 243 of cytochrome P450nor (fungal nitric oxide reductase) corresponds to the 'conserved' Thr in the long I helix of monooxygenase cytochrome P450s. In P450nor, the replacement of Thr243 with Asn, Ala or Val makes the enzymatic activity dramatically reduce. In order to understand the roles of Thr243 in the reduction reaction of NO by P450nor, the crystal structures of three Thr243 mutants (Thr243-->Asn, Thr243-->Val, Thr243-->Ala) of P450nor were determined at a 1.4-A resolution and at cryogenic temperature. However, the hydrogen-bonding pattern in the heme pocket of these mutants is essentially similar for that of the WT enzyme. This suggests that the determination of the structure of the NADH complex of P450nor is required, in order to evaluate the role of Thr243 in its enzymatic reaction. We attempted to crystallize the NADH complex under several conditions, but have not yet been successful. 相似文献
106.
Myoglobin mutants giving the largest geminate yield in CO rebinding in the nanosecond time domain.
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We have measured the rebinding of carbon monoxide (CO) to some distal mutants of myoglobin (Mb) in the time range from 10(-8) to 10(-1) s by flash photolysis, in which the photodissociated CO rebinds to the heme iron without escaping to the solvent water from the protein matrix. We have found that the double mutants [His64-->Val/Val68-->Thr (H64V/V68T) and His64-->Val/Val68-->Ser (H64V/V68S)] have an extremely large geminate yield (70-80%) in water at 5 degreesC, in contrast to the 7% of the geminate yield of wild-type Mb. The CO geminate yields for these two mutants are the largest in those of Mb mutants reported so far, showing that the two mutants have a unique heme environment that favors CO geminate rebinding. Comparing the crystal structures and 1H-NMR and vibrational spectral data of H64V/V68T and H64V/V68S with those of other mutants, we discuss factors that may control the nanosecond geminate CO rebinding and CO migration in the protein matrix. 相似文献
107.
The plasmid pCI6, carrying the attP site of the temperate phage phiU, integrates into the attB site on the chromosome of Rhizobium leguminosarum biovar trifolii strain 4S. The 4 kb EcoRI-HindIII region of pCI6 involved in site-specific integration was subcloned as the attP fragment of phage phiU and sequenced. The attL fragment, one of the new DNA junctions generated from the insertion of pCI6 into the chromosome of the host Rhizobium, was used as a hybridization probe for isolation of the attB fragment of strain 4S. The nucleotide sequence of the 2 kb PstI fragment of strain 4S, which hybridized with the attL fragment, was decided and compared with that of the attP fragment. A 53 bp common sequence was expected to be the core sequence of site-specific integration between phage phiU and strain 4S. One of the ORFs on the attP fragment, which was located adjacent to the core sequence, had structural homology to the integrase family. However, the attB fragment showed high homology with the tRNA genes of Agrobacterium tumefaciens and E. coli. A 47 bp sequence of the 53 bp core sequence overlapped with this tRNA-like sequence. This indicates that the target site of phage phiU integration is the putative tRNA gene on the chromosome of the Rhizobium host. 相似文献
108.
Ski slope vegetation at Snoqualmie Pass in Washington State, USA, was surveyed in order to identify community types and to compare it with vegetation development patterns in Japan. Ski slopes in Japan, most of which were constructed after 1960, underwent heavy land recontouring, while those at Snoqualmie Pass were constructed before 1950 with less modification. Three points apply to Japanese ski slope vegetation and differentiate these slopes from those at Snoqualmie Pass: (i) grasslands of introduced species are widespread and persistent; (ii) unvegetated patches are uncommon; and (iii) wetland vegetation has developed. These differences are mainly derived from the intensity of human impact, history of the slope and its scale: namely, ski slopes in Washington are older and larger than those in Japan. Ski slope vegetation in Washington was primarily differentiated by a soil moisture gradient. The large size of Washington ski slopes permitted the inclusion and development of wetland habitats, whereas most ski slopes in Japan are constructed on ridges and do not contain wetlands. Most introduced species in Japan are eliminated soon after seeding. In contrast, the long-term management of ski slopes decreased soil erosion and/or unvegetated patches in Washington and created relatively permanent grasslands composed of introduced species. Tsuga heterophylla and Abies amabilis were found established on the ski slopes in Washington, whereas in Japan the pioneer tree species are shade-intolerant broadleaved species. These differences may be a result of the different disturbance histories of ski slopes in the two countries. In addition, along with the conifers, early successional forbs such as Anaphalis margaritacea and Epilobium angustifolium are well established on Washington ski slopes. Results show that disturbances created by ski slope development greatly affect the vegetation, even on older, less heavily impacted ski slopes. 相似文献
109.
Ren Matsuba Kensuke Sakai Minako Imamura Yasushi Tanaka Minoru Iwata Hiroshi Hirose Kohei Kaku Hiroshi Maegawa Hirotaka Watada Kazuyuki Tobe Atsunori Kashiwagi Ryuzo Kawamori Shiro Maeda 《PloS one》2015,10(5)
AimWe performed a replication study in a Japanese population to evaluate the association between type 2 diabetes and 7 susceptibility loci originally identified by European genome-wide association study (GWAS) in 2012: ZMIZ1, KLHDC5, TLE1, ANKRD55, CILP2, MC4R, and BCAR1. We also examined the association of 3 additional loci: CCND2 and GIPR, identified in sex-differentiated analyses, and LAMA1, which was shown to be associated with non-obese European type 2 diabetes.MethodsWe genotyped 6,972 Japanese participants (4,280 type 2 diabetes patients and 2,692 controls) for each of the 10 single nucleotide polymorphisms (SNPs): rs12571751 in ZMIZ1, rs10842994 near KLHDC5, rs2796441 near TLE1, rs459193 near ANKRD55, rs10401969 in CILP2, rs12970134 near MC4R, rs7202877 near BCAR1, rs11063069 near CCND2, rs8108269 near GIPR, and rs8090011 in LAMA1 using a multiplex polymerase chain reaction invader assay. The association of each SNP locus with the disease was evaluated using a logistic regression analysis.ResultsAll SNPs examined in this study had the same direction of effect (odds ratio > 1.0, p = 9.77 × 10-4, binomial test), as in the original reports. Among them, rs12571751 in ZMIZ1 was significantly associated with type 2 diabetes [p = 0.0041, odds ratio = 1.123, 95% confidence interval 1.037–1.215, adjusted for sex, age and body mass index (BMI)], but we did not observe significant association of the remaining 9 SNP loci with type 2 diabetes in the present Japanese population (p ≥ 0.005). A genetic risk score, constructed from the sum of risk alleles for the 7 SNP loci identified by un-stratified analyses in the European GWAS meta-analysis were associated with type 2 diabetes in the present Japanese population (p = 2.3 × 10-4, adjusted for sex, age and BMI).ConclusionsZMIZ1 locus has a significant effect on conferring susceptibility to type 2 diabetes also in the Japanese population. 相似文献
110.