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101.
Kitagawa Hiroshi; Oyama Mika; Masayama Kimiko; Yamaguchi Yu; Sugahara Kazuyuki 《Glycobiology》1997,7(8):1175-1180
Decorin is a small flbroblast proteoglycan consisting of a coreprotein and a single chondroitin/dermatan sulfate chain. Thestructure of the carbohydrate-protein linkage region of therecombinant decorin expressed in Chinese hamster ovary cellswas investigated. The decorin was secreted in the culture mediumand isolated by anion-exchange chromatography. The glycosaminoglycanchain was released from the decorin by β-elimination usingalkaline NaBH4, and then digested with chondroitinase ABC. Thesetreatments resulted in a major and a few minor hexasaccharidealditols derived from the carbohydrate-protein linkage region.Their structures were analyzed by enzymatic digestion in conjunctionwith high-performance liquid chromatography. Two of these compoundshave the conventional hexasaccharide core, HexA1-3GalNAcβ1-4GlcAβ1-3Galβ1-3Galβ1-4Xyl-ol.One is nonsulfated, and the other is monosulfated on C4 of theGalNAc residue. They represent 12% and 60% of the total linkageregion, respectively. The other compound has the hexasaccharidealditol with an internal iduronic acid residue HexA1-3GalNAc(4-sulfate)β1-4IdoA1-3GaIβ1-3Galβ1-4Xyl-ol,which was previously demonstrated in one of the five linkagehexasaccharide alditols isolated from dennatan sulfate proteoglycansof bovine aorta (Sugahara et al, J. Biol Chem., 270, 7204–7212,1995).The compound accounts for 11% of the total linkage region. Thesestructural variations in the linkage hexasaccharide region ofthe decorin strikingly contrast to the uniformity demonstratedin the linkage hexasaccharide structure of human inter--trypsininhibitor (Yamada et al, Glycobiology, 5, 335–341,1995)and urinary trypsin inhibitor (Yamada et al, Eur. J. Biochem.,233, 687–693, 1995), both of which have a single chondroi-tinsulfate chain with a uniform linkage hexasaccharide structure,HexA1-3GalNAc(4-sulfate)β1-4GlcAβ1-3Gal(4-sulfate)β1-3Galβ1-4Xyl,containing a 4-O-sulfated Gal residue. chondroitin sulfate decorin dermatan sulfate glycosaminoglycan proteoglycan 相似文献
102.
Philip G. Penketh Krishnamurthy Shyam Raymond P. Baumann Rui Zhu Kimiko Ishiguro Alan C. Sartorelli Elena S. Ratner 《Analytical biochemistry》2016
Alkylating agents are a significant class of environmental carcinogens as well as commonly used anticancer therapeutics. Traditional alkylating activity assays have utilized the colorimetric reagent 4-(4-nitrobenzyl)pyridine (4NBP). However, 4NBP based assays have a relatively low sensitivity towards harder, more oxophilic alkylating species and are not well suited for the identification of the trapped alkyl moiety due to adduct instability. Herein we describe a method using water as the trapping agent which permits the trapping of simple alkylating electrophiles with a comparatively wide range of softness/hardness and permits the identification of donated simple alkyl moieties. 相似文献
103.
The invasion of non‐native species that are closely related to native species can lead to competitive elimination of the native species and/or genomic extinction through hybridization. Such invasions often become serious before they are detected, posing unprecedented threats to biodiversity. A Japanese native strain of common carp (Cyprinus carpio) has become endangered owing to the invasion of non‐native strains introduced from the Eurasian continent. Here, we propose a rapid environmental DNA‐based approach to quantitatively monitor the invasion of non‐native genotypes. Using this system, we developed a method to quantify the relative proportion of native and non‐native DNA based on a single‐nucleotide polymorphism using cycling probe technology in real‐time PCR. The efficiency of this method was confirmed in aquarium experiments, where the quantified proportion of native and non‐native DNA in the water was well correlated to the biomass ratio of native and non‐native genotypes. This method provided quantitative estimates for the proportion of native and non‐native DNA in natural rivers and reservoirs, which allowed us to estimate the degree of invasion of non‐native genotypes without catching and analysing individual fish. Our approach would dramatically facilitate the process of quantitatively monitoring the invasion of non‐native conspecifics in aquatic ecosystems, thus revealing a promising method for risk assessment and management in biodiversity conservation. 相似文献
104.
EPITHELIAL COLLAGENS AND GLYCOSAMINOGLYCANS IN THE EMBRYONIC CORNEA : Macromolecular Order and Morphogenesis in the Basement Membrane 总被引:27,自引:13,他引:14 下载免费PDF全文
The embryonic corneal epithelium synthesizes both collagen and chondroitin sulfate and excretes them across the basement membrane into the subepithelial space where they assemble into a spiraling orthogonal matrix of fibrils. The assembly of collagen into fibrils is first apparent at the outer face of the basement membrane in a region of ordered chondroitin sulfate molecules. Hyaluronate, another morphogenetically important corneal macromolecule, is produced at these early stages only by the inner endothelium. These correlated biosynthetic and ultrastructural data demonstrate discrete macromolecular products of the two corneal epithelia with differing morphogenetic properties and functions. 相似文献
105.
106.
A sensitive and simple radiochemical assay is described to measure argininosuccinase activity in crude tissue homogenates and cultured cells. The method depends on the use of argininosuccinate labeled uniformly with 14C in the six carbons of the arginine moiety. On incubation in the presence of excess arginase, the [U-14C]arginine formed is measured as the sum of radioactivity in [U-14C]ornithine and [14C]urea. Separation from the substrate is accomplished on a small Domex 1-acetate column eluted with 25 mm acetic acid; ornithine and urea emerge in the first few milliliters while unutilized substrate remains on the column. [14C]Argininosuccinate was synthesized enzymatically from l-[U-14C]arginine and fumarate and isolated and purified as the barium salt. Development of a new purification step has brought the amino acid to a purity of 97% as judged by chromatographic and barium analysis. With the present specific radioactivity, as little as 5 to 10 nmol of product can be accurately measured under kinetically optimum conditions. 相似文献
107.
Kimiko Yamakawa Hisako Yanagi Keijiro Saku Jun Sasaki Takaaki Okafuji Yae Shimakura Koichi Kawai Shigeru Tsuchiya Kohki Takada Setsuya Naito Kikuo Arakawa Hideo Hamaguchi 《Human genetics》1991,86(5):445-449
Summary To assess the relationship between relatively severe hereditary hypercholesterolemia with Achilles tendon xanthomas and the defect of the low density lipoprotein (LDL) receptor gene, family studies were carried out in 17 hypercholesterolemic families. In 16 out of the 17 families, hypercholesterolemia co-segregated with four different gross rearrangements, six different restriction fragment length polymorphism (RFLP) haplotypes, or an abnormal TaqI band of the LDL receptor gene. These findings are compatible with the interpretation that hypercholesterolemia is caused by defective LDL receptor genes, and that the origin of the mutant LDL receptor genes in Japanese generally differs among different pedigrees. In the remaining family, the proband and his sibling, both having relatively severe hypercholesterolemia and Achilles tendon xanthomas, shared an RFLP haplotype, although the proband's other sibling with moderate hypercholesterolemia but without Achilles tendon xanthomas did not. The mutant gene for familial defective apolipoprotein B-100 was not detected in the 17 probands. These data suggest that most, if not all, of the relatively severe hereditary hypercholesterolemia associated with Achilles tendon xanthomas is caused by a defect of the LDL receptor gene. 相似文献
108.
Kimiko Takahashi Jun-Ichi Hata Kiyoshi Mukai Yoshio Sawasaki 《In vitro cellular & developmental biology. Animal》1991,27(7):542-548
Summary The mesothelial cells obtained from human omental adipose tissue showed a typical cobblestone monolayer and reacted strongly
with keratin, but did not have Von Willebrand factor. Ultrastructurally these cells revealed the existence of desmosome-like
cell junctions as well as intracellular canaliculi, tubular structures surrounded by microvilli, and tonofilament-like filaments.
The mesothelial cells grew much faster in the medium containing epidermal growth factor, actively took up acetylated-low density
lipoprotein into their cytoplasm, and released angiotensin-converting enzyme. They also released urokinase-type plasminogen
activator, but only half as much as do human umbilical vein endothelial cells; release of tissue-type plasminogen activator
was not observed. Inasmuch as the mesothelial cells also released plasminogen activator inhibitor-1, as do human umbilical
vein endothelial cells, we could not detect u-PA activity in culture medium. u-PA may play a role in the protection against
adhesion among visceral organs. These observations indicate that cultured human mesothelial cells have characteristics closely
related to those found in human endothelial cells. 相似文献
109.
Mark A. Colwell Noah S. Burrell Michael A. Hardy Kimiko Kayano Jordan J. Muir Wendy J. Pearson Sara A. Peterson Kristin A. Sesser 《Journal of Field Ornithology》2010,81(4):349-360
ABSTRACT Habitat quality, as indexed by the reproductive success of individuals, can greatly influence population growth, especially for rare species near the limits of their range. Along the Pacific coast, the Snowy Plover (Charadrius alexandrinus nivosus) is a threatened species that, in recent years, has been breeding on both riverine gravel bars and ocean beaches in northern California. From 2001 to 2009, we compared the habitat characteristics, breeding phenology, reproductive success, and abundance of Western Snowy Plovers occupying these two habitats. Similar percentages of yearling and adult plovers returned to gravel bars and beaches, but plovers breeding on gravel bars arrived and initiated first clutches 2–3 weeks later than those breeding on beaches. Despite this delay, however, the mean annual fledging success of plovers on gravel bars (1.4 ± 0.4 [SD]) was double that on beaches (0.7 ± 0.3). Differences in cumulative reproductive success produced a stronger pattern. By their sixth year, males on gravel bars had fledged 14.5 ± 2.1 chicks, more than four times the number of young fledged by males on beaches (3.3 ± 3.1). Over 9 years, local population size decreased by about 75%, coincident with a shift in breeding distribution away from high‐quality gravel bars to ocean beaches. This unexpected population decline and shift to poorer quality beaches may have been related to occasional low survival of plovers that over‐winter exclusively on beaches in our study area. Consistently low productivity of plovers breeding on ocean beaches suggests the need for intensified management to ameliorate the negative impacts of predation and human activity on the recovery of this population. 相似文献
110.
Ryoji Yoshimura Kimiko Minami Junichiro Matsuda Naoki Sawada Shinji Miura 《Bioscience, biotechnology, and biochemistry》2016,80(2):288-290
Leucine is known to increase mTOR-mediated phosphorylation of 4EBP. In this study, leucine was administered to skeletal muscle-PGC-1α knockout mice. We observed attenuated 4EBP phosphorylation in the skeletal muscle, but not in the liver, of the PGC-1α knockout mice. These data suggest that skeletal muscle-PGC-1α is important for leucine-mediated mTOR activation and protein biosynthesis. 相似文献