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101.
Seio K Mizuta M Tasaki K Tamaki K Ohkubo A Sekine M 《Bioorganic & medicinal chemistry》2008,16(17):8287-8293
We report the synthesis and properties of oligonucleotides incorporating N(6)-[N-(pyren-1-ylmethyl)carbamoyl]-deoxyadenosine (dA(pymcm)). We designed the ODN which incorporated two consecutive dA(pymcm) residues. It was revealed that on hybridization with the target DNA and RNA oligomers, the fluorescence spectra of ODNs having two consecutive dA(pymcm) molecules near the 5'-terminal position can change from the pyrene monomer emission to the excimer, depending on the chain length of the target DNA and RNA. These results indicated that dA(pymcm)-modified ODNs can be used as interesting hybridization sensors that are sensitive to the size of the target strand. 相似文献
102.
Kaori Matsumoto Yuji Nakai Masaru Hoshino Koki Yamazaki Yoshiaki Takioto Satoru Takadera 《Bioscience, biotechnology, and biochemistry》2017,81(10):1926-1936
Tenascin-C (TNC), an extracellular matrix glycoprotein, plays a pivotal role in tumor growth. However, the mechanism whereby TNC affects tumor biology remains unclear. To investigate the exact role of TNC in primary tumor growth, a mouse mammary tumor cell line, GLMT1, was first developed. Subsequently, global gene expression in GLMT1-derived tumors was compared between wild-type (WT) and TNC-knockout (TNKO) mice. Tumors in WT mice were significantly larger than those in TNKO mice. DNA microarray analysis revealed 447 up and 667 downregulated in the tumors inoculated into TNKO mice as compared to tumors in WT mice. Validation by quantitative gene expression analysis showed that Tnc, Cxcl1, Cxcl2, and Cxcr2 were significantly upregulated in WT mice. We hypothesize that TNC stimulates the CXCL1/2-CXCR2 pathway involved in cancer cell proliferation. 相似文献
103.
Astrocytes with previous chronic exposure to amyloid β‐peptide fragment 1–40 suppress excitatory synaptic transmission 下载免费PDF全文
Hiroyuki Kawano Kohei Oyabu Hideaki Yamamoto Kei Eto Yuna Adaniya Kaori Kubota Takuya Watanabe Ayumi Hirano‐Iwata Junichi Nabekura Shutaro Katsurabayashi Katsunori Iwasaki 《Journal of neurochemistry》2017,143(6):624-634
104.
Chang YC Ikeutsu K Toyama T Choi D Kikuchi S 《Journal of industrial microbiology & biotechnology》2011,38(10):1667-1677
Two rapidly growing propionibacteria that could reductively dechlorinate tetrachloroethylene (PCE) and cis-1,2-dichloroethylene (cis-DCE) to ethylene were isolated from environmental sediments. Metabolic characterization and partial sequence analysis of
their 16S rRNA genes showed that the new isolates, designated as strains Propionibacterium sp. HK-1 and Propionibacterium sp. HK-3, did not match any known PCE- or cis-DCE-degrading bacteria. Both strains dechlorinated relatively high concentrations of PCE (0.3 mM) and cis-DCE (0.52 mM) under anaerobic conditions without accumulating toxic intermediates during incubation. Cell-free extracts of
both strains catalyzed PCE and cis-DCE dechlorination; degradation was accelerated by the addition of various electron donors. PCE dehalogenase from strain
HK-1 was mediated by a corrinoid protein, since the dehalogenase was inactivated by propyl iodide only after reduction by
titanium citrate. The amounts of chloride ions (0.094 and 0.103 mM) released after PCE (0.026 mM) and cis-DCE (0.05 mM) dehalogenation using the cell-free enzyme extracts of both strains, HK-1 and HK-3, were stoichiometrically
similar (91 and 100%), indicating that PCE and cis-DCE were fully dechlorinated. Radiotracer studies with [1,2-14C] PCE and [1,2-14C] cis-DCE indicated that ethylene was the terminal product; partial conversion to ethylene was observed. Various chlorinated aliphatic
compounds (PCE, trichloroethylene, cis-DCE, trans-1,2-dichloroethylene, 1,1-dichloroethylene, 1,1-dichloroethane, 1,2-dichloroethane, 1,2-dichloropropane, 1,1,2-trichloroethane,
and vinyl chloride) were degraded by cell-free extracts of strain HK-1. 相似文献
105.
Yasuko Kawamura-Konishi Kaori Chiba Hiroshi Kihara Haruo Suzuki 《European biophysics journal : EBJ》1992,21(2):85-92
Kinetics of the reconstitution of hemoglobin from semihemoglobins and with hemin dicyanide have been investigated using three kinds of stopped-flow technique (Soret absorption, fluorescence quenching of tryptophan, and Soret CD). The semihemoglobins and are occupied by heme in the and chains, respectively, the other chain being heme-free. Based on the kinetic results, the following scheme for the reconstitution is proposed; First, hemin dicyanide enters the pocket-like site of the apo chains. Second, in semihemoglobin , the CN-ligand in the fifth coordination position of iron is replaced by the imidazole ring of the proximal His immediately after the heme insertion. In contrast, semihemoglobin changes its conformation after the heme insertion, and this is followed by the ligand replacement. Finally, the partial structure changes induced by the ligand replacement propagate onto the whole molecule and the final conformation is attained. The results indicate that semihemoglobin retains a more rigid and organized structure, and more closely approaches its final structure than does semihemoglobin .
Correspondence to: Y. Kawamura-Konishi 相似文献
106.
Kobayashi I Shidara K Okuno S Yamada S Imanishi Y Mori K Ishimura E Shoji S Yamakawa T Inaba M 《Life sciences》2012,90(5-6):212-218
AimsHigher serum alkaline phosphatase predicts lower mortality in chronic kidney disease and hemodialysis patients without liver dysfunction because it reflects high bone turnover. The purpose of our study was to compare the significance of serum bone alkaline phosphatase (BAP) with that of other bone markers in prediction of all-cause mortality(ACM) in male hemodialysis patients.Main methodsThe study was performed for 5 years. Serum BAP, intact osteocalcin (iOC), ß-CrossLaps (CTX), and intact parathyroid hormone (iPTH) were measured in 196 male hemodialysis patients without radiographic fracture. Their day-to-day variation during 5 consecutive days and diurnal variation were determined in 13 healthy males.Key findingsThe patients were divided into higher and lower groups based on serum levels of bone markers(mean ± SD: iPTH 218.6 ± 214.5 pg/ml, BAP 23.6 ± 12.2U/L, iOC 42.8 ± 45.2 ng/ml, CTX 1.71 ± 1.23 nmol/L BCE). In Kaplan–Meier analysis, the higher BAP group had significantly higher ACM than the lower BAP group (P = 0.013), whereas mortality did not differ between the higher and lower groups in other markers. Cox regression hazard analysis identified higher log BAP as a significant independent predictor [hazard ratio(HR) 8.32(95%CI:1.18–58.98)] for ACM after adjustment for various factors including pre-existing cardiovasucular disease, presence of DM. The significant association of mortality with serum BAP alone, in contrast with other markers including CTX [HR0.64 (95%CI:0.16–2.47)], iOC [HR0.97(95%CI:0.36–2.64)], iPTH [HR0.84(95%CI:0.44–1.60)],it may be due to the narrower day-to-day variation and the absence of diurnal variation in serum BAP compared to other markers.SignificanceHigher serum BAP may be a predictor of ACM in male hemodialysis patients. 相似文献
107.
108.
Kaori Bonkohara Maiko Fuji Akito Nakao Noriyuki Igura 《Bioscience, biotechnology, and biochemistry》2016,80(3):533-539
To prepare an aroma mixture of Japanese soy sauce by fewest components, the aroma concentrate of good sensory attributes was prepared by polyethylene membrane extraction, which could extract only the volatiles with diethyl ether. GC-MS-Olfactometry was done with the aroma concentrate, and 28 odor-active compounds were detected. Application of aroma extract dilution analysis to the separated fraction revealed high flavor dilution factors with respect to acetic acid, 4-hydroxy-2(or5)-ethyl-5(or2)-methyl-3(2H)-furanone (HEMF), 3-methyl-1-butanol (isoamyl alcohol), and 3-(methylsulfanyl)propanal (methional). A model aroma mixture containing above four odorants showed a good similarity with the aroma of the soy sauce itself. Consequently, the reminiscent aroma mixture of soy sauce was prepared in water. The ratio of acetic acid, HEMF, isoamyl alcohol, and methional was 2500:300:100:1. 相似文献
109.
Yoshiaki Tsuda Haruo Sawada Takafumi Ohsawa Katsuhiro Nakao Hiroki Nishikawa Yuji Ide 《Tree Genetics & Genomes》2010,6(3):377-387
We evaluated the genetic structure of 16 Betula maximowicziana populations in the Chichibu mountain range, central Japan, located within a 25-km radius; all but two populations were at
altitudes of 1,100–1,400 m. The results indicate the effects of geographic topology on the landscape genetic structure of
the populations and should facilitate the development of local-scale strategies to conserve and manage them. Analyses involving
11 nuclear simple sequence repeat loci showed that most populations had similar intrapopulation genetic diversity parameters.
Population differentiation (F
ST = 0.021, G′ST = 0.033) parameters for the populations examined were low but were relatively high compared to those obtained in a previous
study covering populations in a much larger area with a radius of approximately 1,000 km (F
ST = 0.062, G′ST = 0.102). Three populations (Iriyama, Kanayamasawa, and Nishizawa) were differentiated from the other populations by Monmonier’s
and spatial analysis of molecular variance algorithms or by STRUCTURE analysis. Since a high mountain ridge (nearly 2,000 m)
separates the Kanayamasawa and Nishizawa populations from the other 14 populations and the Kanayamasawa and Nishizawa populations
are themselves separated by another mountain ridge, the genetic structure appears to be partly due to mountain ridges acting
as genetic barriers and restricting gene flow. However, the Iriyama population is genetically different but not separated
by any clear geographic barrier. These results show that the landscape genetic structure is complex in the mountain range
and we need to pay attention, within landscape genetic studies and conservation programs, to geographic barriers and local
population differentiation. 相似文献
110.
Tajino K Matsumura K Kosada K Shibakusa T Inoue K Fushiki T Hosokawa H Kobayashi S 《American journal of physiology. Regulatory, integrative and comparative physiology》2007,293(5):R2128-R2135
When ambient temperature is decreased in mammals, autonomic and behavioral heat-gain responses occur to maintain their core temperatures. However, what molecules in cutaneous sensory nerve endings mediate cooling-induced responses is unclear. Recently, transient receptor potential melastatin-8 (TRPM8) has been identified in cell bodies of sensory neurons as low-temperature and menthol-activated cation channel. We hypothesized that TRPM8 mediates cooling-induced autonomic and behavioral heat-gain responses. To activate TRPM8 specifically, we applied 1-10% menthol to the skin of whole trunk in mice instead of cooling and measured core temperatures and autonomic and behavioral heat-gain responses. Solvent of menthol (100% ethanol) was used as control. Significant elevation of core temperatures was observed between 20 and 120 min after menthol application. Pretreatment with diclofenac sodium, an antipyretic drug, did not affect this hyperthermia, indicating that the menthol-induced hyperthermia is not fever. Menthol application induced a rise in oxygen consumption, shivering-like muscle activity, tail skin vasoconstriction (autonomic responses), and heat-seeking behavior. All of them are typical heat-gain responses. These results support the hypothesis that TRPM8 mediates cooling-induced autonomic and behavioral heat-gain responses. 相似文献