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91.
Okishima N Hagiwara Y Seito T Yano M Kido H 《Biochemical and biophysical research communications》1999,256(1):1-5
We established highly sensitive and specific sandwich-enzyme immunoassays (EIAs) for three newly discovered bioactive 31-amino acid endothelins [ETs(1-31)], which can detect as little as 0.16 pg/well of ET-1(1-31), 0.39 pg/well of ET-2(1-31), and 0.16 pg/well of ET-3(1-31). The EIAs showed no crossreactivity with 21-amino acid endothelins [ETs(1-21)] or big ETs at the usual assay concentrations below 1-5 ng/ml. In reversed-phase HPLC, immunoreactive ETs(1-31) in the granulocytes of normal human subjects eluted at the exact positions of authentic ETs(1-31), except for the presence of one additional unknown immunoreactive ET-1(1-31). The results also indicate that ETs(1-31) exist in the granulocytes at levels higher than or similar to those of ETs(1-21). This study is the first to establish EIAs for novel bioactive ETs(1-31). These assays can be utilized to assess the pathophysiological roles of ETs(1-31). 相似文献
92.
93.
Transient hyper-17-OHPnemia unrelated to cross-reactions with residual fetal adrenal cortex products
Mizuno H Ohro Y Sugiyama Y Ito T Hasegawa T Homma K Ueshiba H Ono M Togari H 《Hormone research》2004,61(5):242-245
OBJECTIVE: To clarify the pathogenesis of transient hyper-17alpha-hydroxyprogesteronemia, we initiated a laboratory investigation in a pre-term infant with persistently high serum 17alpha-hydroxyprogesterone (17-OHP) until 2 months of age. METHODS: Serum 17-OHP level was measured by high-performance liquid chromatography and radioimmunoassay, and gene analysis of CYP21A2 (21-hydroxylase) was performed. RESULT: Serum 17-OHP level on the 29th day of life was 25.4 ng/ml, and the urinary steroid profile showed low pregnanetriolone. Gene analysis of 21-hydroxylase disclosed no mutation, and 17-OHP normalized by 3 months of age without specific treatment. CONCLUSION: Transient elevations in 17-OHP, which do not appear related to cross-reactions with products of a residual fetal adrenal cortex, may occur in the first few months of life. 相似文献
94.
Ueda K Yamashita A Ishikawa J Shimada M Watsuji TO Morimura K Ikeda H Hattori M Beppu T 《Nucleic acids research》2004,32(16):4937-4944
Symbiobacterium thermophilum is an uncultivable bacterium isolated from compost that depends on microbial commensalism. The 16S ribosomal DNA-based phylogeny suggests that this bacterium belongs to an unknown taxon in the Gram-positive bacterial cluster. Here, we describe the 3.57 Mb genome sequence of S.thermophilum. The genome consists of 3338 protein-coding sequences, out of which 2082 have functional assignments. Despite the high G + C content (68.7%), the genome is closest to that of Firmicutes, a phylum consisting of low G + C Gram-positive bacteria. This provides evidence for the presence of an undefined category in the Gram-positive bacterial group. The presence of both spo and related genes and microscopic observation indicate that S.thermophilum is the first high G + C organism that forms endospores. The S.thermophilum genome is also characterized by the widespread insertion of class C group II introns, which are oriented in the same direction as chromosomal replication. The genome has many membrane transporters, a number of which are involved in the uptake of peptides and amino acids. The genes involved in primary metabolism are largely identified, except those that code several biosynthetic enzymes and carbonic anhydrase. The organism also has a variety of respiratory systems including Nap nitrate reductase, which has been found only in Gram-negative bacteria. Overall, these features suggest that S.thermophilum is adaptable to and thus lives in various environments, such that its growth requirement could be a substance or a physiological condition that is generally available in the natural environment rather than a highly specific substance that is present only in a limited niche. The genomic information from S.thermophilum offers new insights into microbial diversity and evolutionary sciences, and provides a framework for characterizing the molecular basis underlying microbial commensalism. 相似文献
95.
Kawai K Hagiwara T Takai R Suzuki T 《Bioscience, biotechnology, and biochemistry》2004,68(11):2285-2288
The Maillard Reaction (MR) rate below the glass transition temperature (T(g)) for various model glassy food systems was studied at temperatures between 40 degrees C and 70 degrees C. As a sample, freeze-dried glucose and lysine systems embedded in various glassy matrices (e.g., polyvinylpyrrolodone and trehalose) were used, and the MR rate below the T(g) was compared among the various glassy matrices. The extent of MR was estimated spectrophotometrically from the optical density at 280 nm (OD(280)), and the MR rate (k(280)) was determined as a pseudo zero order reaction rate from the time course of OD(280). Although k(280) was described by the Arrhenius plot, the temperature dependence of k(280) was almost the same and the intercept was different among the matrices. From the comparison of k(280), it was suggested that the MR rate in glassy matrix was affected not only by the T(g), but also by the hydrogen bonding between MR reactants and glassy matrix. 相似文献
96.
Early development of the self-fertilizing mangrove killifish <Emphasis Type="Italic">Rivulus marmoratus</Emphasis> reared in the laboratory 总被引:1,自引:1,他引:0
Maria Vivian?Camacho Gragedadh@stcc.nagasaki-u.ac.jp" title="MVCG dh@stcc.nagasaki-u.ac.jp" itemprop="email" data-track="click" data-track-action="Email author" data-track-label="">Email author Yoshitaka?Sakakura Atsushi?Hagiwara 《Ichthyological Research》2004,51(4):309-315
The mangrove killifish Rivulus marmoratus was reared at 25°±1°C and 17ppt salinity from 0 to 100 days after hatching (DAH), and its early development was described by examining growth and morphometric parameters, meristic characters (vertebral and fin-ray counts), bone-cartilage development, and pigmentation. Growth was isometric for preanal length, head length, snout length, body depth, pectoral-fin length, dorsal-fin length, anal-fin length, and caudal-peduncle depth. Negative allometric growth was observed in eye diameter and gape size. Meristic counts (mean±SD) for vertebrae (34.2±0.4) and dorsal- (8.6±0.5), anal- (11.4±0.5), and caudal-fin rays (30.2±0.8) were complete at 0 DAH (n=5), whereas pectoral-fin rays and pelvic-fin rays were complete by 30 DAH (14.5±0.4, n=5) and 60 DAH (4.2±0.8, n=5). Full ossification of meristic elements proceeded in the following sequence: vertebrae (by 30 DAH), caudal-, dorsal-, and anal-fin rays (by 60 DAH), pectoral-fin rays (between 60 DAH and 100 DAH), and pelvic-fin rays (by 100 DAH). Both morphological characters and meristic counts indicate that this species can be considered to be a juvenile after 9.8mm in standard length (20 DAH). 相似文献
97.
Ogino H Mimitsuka T Muto T Matsumura M Yasuda M Ishimi K Ishikawa H 《Journal of molecular microbiology and biotechnology》2004,7(4):212-223
A lipolytic enzyme gene (lip8) was cloned from organic solvent-tolerant Pseudomonas aeruginosa LST-03 and sequenced. In the sequenced nucleotides, an open reading frame consisting of 1,173 nucleotides and encoding 391 amino acids was found. Lip8 is considered to belong to the family VIII of lipolytic enzymes whose serine in the consensus sequence of -Ser-Xaa-Xaa-Lys- acts as catalytic nucleophile. The gene was expressed in Escherichia coli and purified by a combination of ammonium sulfate fractionation and hydrophobic interaction and ion-exchange chromatographies to homogeneity on SDS-PAGE analysis. The optimum temperature and heat stability of Lip8 were not as high as those of Lip3 and LST-03 lipase, two other lipolytic enzymes from the same strain. Addition of glycerol to a solution containing Lip8 stabilized this enzyme. By measuring the activities against various triacylglycerols and fatty acid methyl esters having carbon chains of different lengths, Lip8 was categorized as an esterase which has higher activities against fatty acid methyl esters with short-chain fatty acids. 相似文献
98.
Ishikura M Hagiwara K Takishita K Haga M Iwai K Maruyama T 《Marine biotechnology (New York, N.Y.)》2004,6(4):378-385
Recent molecular biological studies have revealed that some photosymbiotic invertebrates dwelling in coral reefs host several genetically different dinoflagellates, Symbiodinium species, as symbionts. However, little is known about the difference in physiologic characteristics among these symbionts living in a single host, because some Symbiodinium strains are difficult to culture in vitro. To isolate some of these Symbiodinium strains, we have developed an agar culture medium plate containing antibiotics and a giant clam tissue homogenate. Using-this medium we isolated two new Symbiodinium strains from two molluscan hosts, Tridacna crocea and Pteraeolidia ianthina, each of which hosted two different Symbiodinium strains belonging to Symbiodinium C and D, respectively. The tissue homogenate was essential for the growth of Symbiodinium D. Although it was not essential for the growth of Symbiodinium C, it did stimulate the initial growth. For the isolation of some Symbiodinium strains, isolation medium containing host homogenate is effective. 相似文献
99.
Morozumi K Tateno H Yanagida K Katayose H Kamiguchi Y Sato A 《Zygote (Cambridge, England)》2004,12(4):339-344
Human immunodeficiency virus (HIV) can be inactivated by heating at 56 degrees C for 30 min, treating with 50% ethanol at room temperature for 10 min, or treating with 2% sodium hypochlorite solution (NaClO) at room temperature for 60 min. Using a mouse model, we evaluated the risk of generating chromosome damage in spermatozoa following these treatments. The spermatozoa were all dead after the treatments. Although 41.3% of oocytes injected with ethanol-treated spermatozoa successfully activated, none of the oocytes injected with heated or NaClO-treated spermatozoa activated. When artificial stimulation with strontium was used, the fertilization of oocytes with heated or ethanol-treated spermatozoa was completely rescued. Sperm nuclei treated with NaClO neither decondensed nor developed to a male pronucleus. The incidences of structural chromosome aberrations in 1-cell zygotes derived from the heated spermatozoa (45.6%) and ethanol-treated spermatozoa (91.2%) were significantly higher than those in the matched controls (5.5% and 10.5%, respectively). Further study is needed to develop a methodology for the protection of spermatozoa against chromosome damage or the separation of damaged spermatozoa before intracytoplasmic sperm injection. 相似文献
100.
Kurimoto A Ogino T Ichii S Isobe Y Tobe M Ogita H Takaku H Sajiki H Hirota K Kawakami H 《Bioorganic & medicinal chemistry》2003,11(24):5501-5508
Recently, we have reported the 8-hydroxyadenine derivatives (2–4) as a novel class of interferon (IFN) inducing agents. In the present study, a series of 8-hydroxyadenines, which possess various amino moieties at the adenine C(2)-position, were synthesized and evaluated for their ability to induce endogenous IFN in comparison to the known active agent, Imiquimod. Among the compounds prepared, compound 9o possessing a 2-methoxyethylamino group at C(2)-position of adenine was found to exhibit potent IFN inducing activity in vivo. Compound 9o induced IFN from the dosage of 0.1 mg/kg, which was 30-fold potent than that of Imiquimod, and showed a good oral bioavailability (F=81%). 相似文献