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101.
Akihiro Hirata Yoko Miyamoto Akihisa Kaneko Hiroki Sakai Kyoko Yoshizaki Tokuma Yanai Takako Miyabe‐Nishiwaki Juri Suzuki 《Journal of medical primatology》2019,48(2):137-140
Primary neuroendocrine neoplasm of the liver is extremely rare in both humans and non‐human primates. The present report describes the clinical and pathological findings of an aged Japanese macaque (Macaca fuscata) with hepatic neuroendocrine carcinoma. To our knowledge, this is the first report of hepatic neuroendocrine neoplasm in macaques. 相似文献
102.
Sakamoto Kazunori Ogiwara Natsuko Kaji Tomomitsu Sugimoto Yurie Ueno Mitsuru Sonoda Masatoshi Matsui Akihiro Ishida Junko Tanaka Maho Totoki Yasushi Shinozaki Kazuo Seki Motoaki 《Journal of plant research》2019,132(4):541-568
Journal of Plant Research - Soybean (Glycine max) roots establish associations with nodule-inducing rhizobia and arbuscular mycorrhizal (AM) fungi. Both rhizobia and AM fungi have been shown to... 相似文献
103.
Common marmosets vocalize phee calls as isolation calls, which seem to facilitate their reunion with family groups. To identify multiple acoustic properties with different time courses, we examined acoustic modulations of phees during different social contexts of isolation. Subject marmosets were totally isolated in one condition, were visually isolated and could exchange vocalizations in another condition, and were visually isolated and subsequently totally isolated in a third condition. We recorded 6,035 phees of 10 male–female marmoset pairs and conducted acoustic analysis. The marmosets frequently vocalized phees that were temporally elongated and louder during isolation, with varying time courses of these changes in acoustic parameters. The vocal rates and sound levels of the phees increased as soon as the marmosets saw their pair mates being taken away, and then gradually calmed down. The phee duration was longer in conditions during which there were no vocal responses from their pair mates. Louder vocalizations are conspicuous and seem to be effective for long‐distance transmission, whereas shorter call duration during vocal exchanges might avoid possible vocal overlap between mates. Am. J. Primatol. 72:681–688, 2010. © 2010 Wiley‐Liss, Inc. 相似文献
104.
Akihiro Kondo John Sidney Scott Southwood Marie-France del Guercio Ettore Appella Hiroshi Sakamoto Howard M. Grey Esteban Celis Robert W. Chesnut Ralph T. Kubo A. Sette 《Immunogenetics》1997,45(4):249-258
Previous studies have defined two different peptide binding motifs specific for HLA-A
*
0101. These motifs are characterized by the presence of tyrosine (Y) at the C-termini of 9-mer and 10-mer peptides, and either
a small polar or hydrophobic (S, T, M) residue in position 2, or a negatively charged (D or E) residue in position 3. In this
study, the structural requirements for peptide binding to A
*
0101 have been further analyzed by examining the binding capacity of large sets of peptides corresponding to naturally occurring
sequences which bore one or the other of these two A
*
0101-specific motifs. By correlating the presence of specific residue types at each position along the peptide sequence with increased
(or decreased) binding affinity, the prominent influence of secondary anchor residues was revealed. In most cases, the two
anchors in positions 2 and 3 appear to act synergistically. With the exception of the DE3 submotif in 9-mer peptides, a positive role for aromatic residues in position 1 and the center of the peptide (positions
4 or 5 of 9- or 10-mer peptides, respectively), and proline at C-3, were also consistently detected. However, secondary anchor
residues also appear to differ significantly between the two different submotifs, demonstrating that A
*
0101 can utilize alternative modes in binding its peptide ligands. According to these analyses, specific refined submotifs were
also established, and their merit verified by independent sets of potential A
*
0101 binding peptides. Besides providing useful insight into the nature of the interaction of the A
*
0101 allele with its peptide ligands, such refined motifs should also facilitate accurate prediction of potential A
*
0101-restricted peptide epitopes.
Received: 16 July 1996 / Revised: 18 September 1996 相似文献
105.
Effects of nitric oxide on matrix metalloproteinase-2 production by rheumatoid synovial cells 总被引:9,自引:0,他引:9
Hirai Y Migita K Honda S Ueki Y Yamasaki S Urayama S Kamachi M Kawakami A Ida H Kita M Fukuda T Shibatomi K Kawabe Y Aoyagi T Eguchi K 《Life sciences》2001,68(8):913-920
Nitric oxide (NO) is a multifunctional messenger molecule generated from L-arginine by a family of enzymes, including nitric oxide synthase (NOS). This study was performed to examine whether NO modulates the production of matrix metalloproteinases (MMPs), which degrade all components of extracellular matrix (ECM), in rheumatoid synovial cells. We investigated the effects of exogenously generated NO by a NO donor, S-nitroso-N-acetyl-DL-penicillamine (SNAP), on the MMPs production by rheumatoid synovial cells. Culture media conditioned by SNAP-treated synovial cells were examined by gelatin zymography and immunoblot analysis. Incubation of synovial cells with SNAP resulted in gelatinase A production in a dose-dependent fashion. Furthermore, RT-PCR analysis demonstrated that MMP-2 mRNA expression was induced in SNAP-treated synovial cells. In contrast, SNAP did not influence the production of TIMP-1 and TIMP-2, which preferentially inhibit MMP-2, by rheumatoid synovial cells. Our data indicate that NO could modulate MMP production by rheumatoid synovial cells and therefore contribute to ECM degradation of articular components in RA. 相似文献
106.
Taniyama Y Shibata S Kita S Horikoshi K Fuse H Shirafuji H Sumino Y Fujino M 《Biochemical and biophysical research communications》1999,257(1):50-56
Lecithin cholesterol acyltransferase (LCAT) is the key enzyme in the esterification of plasma cholesterol and in the reverse cholesterol transport on high-density lipoprotein (HDL). We have found a novel LCAT-related gene among differentially expressed cDNA fragments between two types of foam cells derived from THP-1 cells, which are different in cholesterol efflux ability, using a subtractive PCR technique. The deduced 412-amino-acid sequence has 49% amino acid sequence similarity with human LCAT. In contrast to the liver-specific expression of LCAT, mRNA expression of the gene was observed mainly in peripheral tissues including kidney, placenta, pancreas, testis, spleen, heart, and skeletal muscle. The protein exists in human plasma and is probably associated with HDL. Moreover, we discovered that the recombinant protein hydrolyzed lysophosphatidylcholine (lysoPC), a proatherogenic lipid, to glycerophosphorylcholine and a free fatty acid. We have therefore named this novel enzyme LCAT-like lysophospholipase (LLPL), through which a new catabolic pathway for lysoPC on lipoproteins could be elucidated. 相似文献
107.
Kita K Fukura T Nakase KI Okamoto K Yanase H Kataoka M Shimizu S 《Applied and environmental microbiology》1999,65(12):5207-5211
We cloned and sequenced the gene encoding an NADPH-dependent aldehyde reductase (ARII) in Sporobolomyces salmonicolor AKU4429, which reduces ethyl 4-chloro-3-oxobutanoate (4-COBE) to ethyl (S)-4-chloro-3-hydroxybutanoate. The ARII gene is 1,032 bp long, is interrupted by four introns, and encodes a 37,315-Da polypeptide. The deduced amino acid sequence exhibited significant levels of similarity to the amino acid sequences of members of the mammalian 3beta-hydroxysteroid dehydrogenase-plant dihydroflavonol 4-reductase superfamily but not to the amino acid sequences of members of the aldo-keto reductase superfamily or to the amino acid sequence of an aldehyde reductase previously isolated from the same organism (K. Kita, K. Matsuzaki, T. Hashimoto, H. Yanase, N. Kato, M. C.-M. Chung, M. Kataoka, and S. Shimizu, Appl. Environ. Microbiol. 62:2303-2310, 1996). The ARII protein was overproduced in Escherichia coli about 2, 000-fold compared to the production in the original yeast cells. The enzyme expressed in E. coli was purified to homogeneity and had the same catalytic properties as ARII purified from S. salmonicolor. To examine the contribution of the dinucleotide-binding motif G(19)-X-X-G(22)-X-X-A(25), which is located in the N-terminal region, during ARII catalysis, we replaced three amino acid residues in the motif and purified the resulting mutant enzymes. Substrate inhibition of the G(19)-->A and G(22)-->A mutant enzymes by 4-COBE did not occur. The A(25)-->G mutant enzyme could reduce 4-COBE when NADPH was replaced by an equimolar concentration of NADH. 相似文献
108.
Kumagai H Koizumi A Suda A Sato N Sakurai H Kumagai H 《Bioscience, biotechnology, and biochemistry》2004,68(7):1598-1600
Soybean globulins were deamidated after removing phytate using ion-exchange resins, and then hydrolyzed by digestive enzymes. The phytate-removed deamidated soybean globulins (PrDS) retained high calcium-binding ability even after the hydrolysis by digestive enzymes. PrDS and its hydrolysates enhanced calcium absorption from the small intestine when injected into the small intestine together with a calcium solution. 相似文献
109.
Suppressive effect of a hot water extract of adzuki beans (Vigna angularis) on hyperglycemia after sucrose loading in mice and diabetic rats 总被引:3,自引:0,他引:3
Itoh T Kita N Kurokawa Y Kobayashi M Horio F Furuichi Y 《Bioscience, biotechnology, and biochemistry》2004,68(12):2421-2426
A hot water extract obtained by boiling adzuki beans (Vigna angularis) to produce bean paste for Japanese cake showed inhibitory activity against alpha-glucosidase, alpha-amylase, maltase, sucrase, and isomaltase after HP-20 column chromatography. The IC(50) values for each hydrolylase were 0.78 mg/ml (alpha-amylase), 2.45 mg/ml (maltase), 5.37 mg/ml (sucrase), and 1.75 mg/ml (isomaltase). The active fraction showed potential hypoglycemic activity in both normal mice and streptozotocin (STZ)-induced diabetic rats after an oral administration of sucrose, but did not show any effect on the blood glucose concentration after glucose administration, suggesting that the active fraction suppressed the postprandial blood glucose level by inhibiting alpha-glucosidase and alpha-amylase, irrespective of the endogenous blood insulin level. 相似文献
110.