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991.
Yoshitaka Furuta Masaaki Kobayashi Tamotsu Masaki Ken Takamatsu 《Neurochemical research》1999,24(5):651-658
Expression of hippocalcin and neural visinin-like calcium-binding protein 2 (NVP2) in aging rat brain was investigated by immunoblot and immunohistochemical analyses. In 3-month old rats, hippocalcin and NVP2 were present at high concentrations in hippocampal and cerebral pyramidal cells and dentate granule cells, with hippocalcin protein levels being five to ten times higher than NVP2 levels. Hippocalcin levels in hippocampus and cerebral cortex decreased by approximately 20% at 24 months. While the number of hippocalcin-positive cells in CA3, dentate gyrus and cerebral cortex were preserved, staining intensity decreased. In contrast, the number and staining intensity of hippocalcin-positive cells in CA1 were maintained. NVP2 levels in hippocampus and cerebral cortex decreased by approximately 30% at 24 months. In cerebral cortex, the number and intensity of NVP2-positive cells decreased. In CA1 through CA3 and in dentate gyrus, NVP2-positive cell numbers were preserved, but staining intensity decreased. In summary, the loss of hippocalcin and NVP2 in aging rat brain may be associated with age-related impairment of postsynaptic functions. 相似文献
992.
993.
Huang J Sutliff TD Wu L Nandi S Benge K Terashima M Ralston AH Drohan W Huang N Rodriguez RL 《Biotechnology progress》2001,17(1):126-133
Human alpha-1-antitrypsin (AAT), the most abundant protease inhibitor found in the blood, was expressed in rice embryonic tissue suspension cell culture. This was accomplished by cloning the codon-optimized AAT gene into a vector containing the rice RAmy3D promoter and its signal sequence. The synthetic gene incorporates codons synonymous with those found in highly expressed rice genes. Approximately 1000 stable transformed calli were produced by particle bombardment mediated transformation and were screened for high AAT expression using a porcine elastase inhibitory activity assay. The band shift assay also confirmed that rice-derived AAT is functional regarding its binding capability to the elastase substrate. Time course studies were conducted to determine the optimum, postinduction expression levels from cell culture. AAT expression equivalent to 20% of the total secreted proteins was achieved, and a purification scheme was developed that yielded active AAT with purity greater than 95%. The potential applications of purified plant-derived AAT for treatments of various AAT-deficient diseases are discussed. 相似文献
994.
Arima Y Harada M Kamimura D Park JH Kawano F Yull FE Kawamoto T Iwakura Y Betz UA Márquez G Blackwell TS Ohira Y Hirano T Murakami M 《Cell》2012,148(3):447-457
Although it is believed that neural activation can affect immune responses, very little is known about the neuroimmune interactions involved, especially the regulators of immune traffic across the blood-brain barrier which occurs in neuroimmune diseases such as multiple sclerosis (MS). Using a mouse model of MS, experimental autoimmune encephalomyelitis, we show that autoreactive T?cells access the central nervous system via the fifth lumbar spinal cord. This location is defined by IL-6 amplifier-dependent upregulation of the chemokine CCL20 in associated dorsal blood vessels, which in turn depends on gravity-induced activation of sensory neurons by the soleus muscle in the leg. Impairing soleus muscle contraction by tail suspension is sufficient to reduce localized chemokine expression and block entry of pathogenic T?cells at the fifth lumbar cord, suggesting that regional neuroimmune interactions may offer therapeutic targets for a variety of neurological diseases. 相似文献
995.
Stereoselective Reduction of Ethyl 4-Chloro-3-Oxobutanoate by a Microbial Aldehyde Reductase in an Organic Solvent-Water Diphasic System 总被引:7,自引:1,他引:7 下载免费PDF全文
Sakayu Shimizu Michihiko Kataoka Masaaki Katoh Tadashi Morikawa Teruzo Miyoshi Hideaki Yamada 《Applied microbiology》1990,56(8):2374-2377
Enzyme-catalyzed asymmetric reduction of ethyl 4-chloro-3-oxobutanoate in an organic solvent-water diphasic system was studied. NADPH-dependent aldehyde reductase isolated from Sporobolomyces salmonicolor AKU4429 and glucose dehydrogenase were used as catalysts for reduction of ethyl 4-chloro-3-oxobutanoate and recycling of NADPH, respectively, in this system. In an aqueous system, the substrate was unstable. Inhibition of the reaction and inactivation of the enzymes by the substrate and the product were also observed. An n-butyl acetate-water diphasic system very efficiently overcame these limitations. In a 1,600-ml−1,600-ml scale diphasic reaction, ethyl (R)-4-chloro-3-hydroxybutanoate (0.80 mol; 86% enantiomeric excess) was produced from the corresponding oxoester in a molar yield of 95.4% with an NADPH turnover of 5,500 mol/mol. 相似文献
996.
997.
Masaaki Konishi Shinro Nishi Tokuma Fukuoka Dai Kitamoto Tomo-o Watsuji Yuriko Nagano Akinori Yabuki Satoshi Nakagawa Yuji Hatada Jun-ichi Horiuchi 《Marine biotechnology (New York, N.Y.)》2014,16(4):484-493
Glycolipid biosurfactant-producing bacteria were isolated from deep-sea sediment collected from the Okinawa Trough. Isolate BS15 produced the largest amount of the glycolipid, generating up to 6.31?±?1.15 g l?1 after 4 days at 20 °C. Glucose was identified in the hydrolysate of the purified major component of the biosurfactant glycolipid. According to gas chromatography/mass spectrometry analysis, the hydrophobic moieties in the major component were hexadecanoate, octadecanoate, 3-hydroxyhexadecanoate, 2-hydroxyoctanoate, and succinate. The molecular weight of the purified major glycolipid was calculated to be 1,211, while 1H and 13C nuclear magnetic resonance spectra confirmed that the major component consisted of 2 mol of α-glucoside and 1 mol of β-glucoside. The molecular structure was assigned as novel trisaccharide-type glycolipid biosurfactant, glucotriose lipids. The critical micelle concentration of the purified major glycolipid was 2.3?×?10?6 M, with a surface tension of 29.5 mN m?1. Phylogenetic analysis showed isolate BS15 was closely related to a Rhodococcus strains isolated from Antarctica, and to Rhodococcus fascians, a phytopathogen. PCR analysis showed that the fasA, fasB, fasC, fasD, fasE, and fasF genes, which are involved in phytohormone-like cytokinin production, were not present in the genome of BS15; however, analysis of a draft genome sequence of BS15 (5.5 Mb) identified regions with 31 %, 53 %, 46 %, 30 %, and 31 % DNA sequence identity to the fasA, fasB, fasC, and fasD genes, respectively. 相似文献
998.
999.
Ueda M Ando Y Hakamata Y Nakamura M Yamashita T Obayashi K Himeno S Inoue S Sato Y Kaneko T Takamune N Misumi S Shoji S Uchino M Kobayashi E 《Biochemical and biophysical research communications》2007,352(2):299-304
Amyloidogenic transthyretin (ATTR) is the pathogenic protein of familial amyloidotic polyneuropathy (FAP). To establish a tool for analyses of ATTR metabolisms including after liver transplantations, we developed a transgenic rat model expressing human ATTR V30M and confirmed expressions of human ATTR V30M in various tissues. Mass spectrometry for purified TTR revealed that rat intrinsic TTR and human ATTR V30M formed tetramers. Congo red staining and immunohistochemistry revealed that nonfibrillar deposits of human ATTR V30M, but not amyloid deposits, were detected in the gastrointestinal tracts of the transgenic rats. At 24h after liver transplantation, serum human ATTR V30M levels in transgenic rats that received livers from normal rats became lower than detectable levels. These results thus suggest that this transgenic rat may be a useful animal model which analyzes the metabolism of human ATTR V30M including liver transplantation studies. 相似文献
1000.
Yuko Maki Hiroshi Soejima Tamizi Sugiyama Takeo Sato Junji Yamaguchi Masaaki K. Watahiki 《Plant Biotechnology》2022,39(2):173
3-Phenyllactic acid (PLA) is a common secondary product of Lactobacillus sp. and promotes adventitious-root formation in Azuki beans (Vigna angularis). Root promotion activity of PLA is synergistically enhanced by tryptophan (Trp). In this study, stereoisomers of PLA and Trp amide conjugates and their alkyl esters were synthesized to investigate the structure–activity relationships on root-promotion activity. The rooting activity of D-PLA-L-Trp conjugate shows more than 40 times higher than that of the mixture of D-PLA and L-Trp. Modification of PLA-Trp with ethyl ester showed the highest activity at 3,400 times of a mixture of D-PLA and L-Trp. However, L-or D-PLA-D-Trp conjugate and the isopropyl ester of PLA-Trp conjugates, both lost the root promotion activity and implicated that a requirement for steric structure for PLA related root promotion mechanism. Unlike auxin substances, which are commonly used as rooting agents that displayed high activity in low concentrations, PLA-Trp ethyl ester exhibited far less phytotoxicity at high concentration of 1 mM, despite its high rooting activity. Innovation of PLA-Trp ethyl ester may be expected for agricultural aspects with low environmental impact. 相似文献