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51.
Mariyo F. Watanabe Ken-Ichi Harada Kennji Matsuura Masayuki Watanabe Makoto Suzuki 《Journal of applied phycology》1989,1(2):161-165
Changes in the content of cyclic heptapeptide hepatotoxins called microcystins were investigated during batch culture of two
Microcystis species using high performance liquid chromatography. After adsorption to ODS-silica gel cartridges and elution with methanol,
the toxins were analyzed and quantified by HPLC. 35 μg per 100 mg dry cells of microcystin-RR, 34 μg of -YR and 43 μg of -LR
were present at the beginning of the exponential growth phase of M. viridis. Microcystin-RR increased markedly towards the end of the exponential phase with the maximum content of 112 μg per 100 mg
cells was measured at the late stage of the exponential phase. A remarkable increase of microcystin-YR from 130 μg per 100
mg cells to 1020 μg was observed during the exponential phase of a highly toxic strain of M. aeruginosa. However no clear differences were found in the pattern of change among the three toxins during the growth course. 相似文献
52.
Ontogenesis of α2 -Adrenoceptor Coupling with GTP-Binding Proteins in the Rat Telencephalon 总被引:2,自引:2,他引:0
Yoshihisa Kitamura Makoto Mochii Ryuji Kodama Kiyokazu Agata Kenji Watanabe Goro Eguchi Yasuyuki Nomura 《Journal of neurochemistry》1989,53(1):249-257
The ontogenesis of alpha 2-adrenoceptors and GTP-binding proteins and their coupling activity were investigated in telencephalon membranes of developing rats. The manganese-induced elevation of [3H]clonidine binding was increased in an age-dependent manner but the guanosine 5'-O-(3-thio)triphosphate-induced decrease in binding did not change. The extent of the binding of [3H]clonidine at 15 nM (saturable concentration) increased in an age-dependent manner and reached the adult level at 4 days after birth. Cholera toxin and pertussis toxin catalyzed ADP-ribosylation of proteins of 46 and 41/39 kilodaltons (kDa) in solubilized cholate extracts of the membranes. The 41/39-kDa proteins ADP-ribosylated by pertussis toxin (Gi alpha + Go alpha) were increased with age and reached the adult level at day 12, whereas the 46-kDa protein (Gs alpha) reached its peak on day 12 and then decreased to the fetal level at the adult stage. The immunoblot experiments of the homogenates with antiserum (specific antibody against alpha- and beta-subunit of GTP-binding proteins) demonstrated that the 39-kDa alpha-subunit of (Go alpha) and the 36-kDa beta-subunit of GTP-binding protein (beta 36) increased with postnatal age. In contrast, 35-kDa beta-subunit (beta 35) did not change. From these results, it is suggested that the coupling activity of alpha 2-adrenoceptor with GTP-binding protein gradually develops in a manner parallel with the increase of alpha 2-adrenoceptor and pertussis toxin sensitive GTP-binding proteins, Gi, and that alpha 39 beta 36 gamma may be related to the differentiation and/or growth of nerve cells in rat telencephalon. 相似文献
53.
Elastase-1-secreting acinar cell carcinoma of the pancreas. A cytologic, electron microscopic and histochemical study 总被引:2,自引:0,他引:2
A case of acinar cell carcinoma of the pancreas was diagnosed by fine needle aspiration cytology during surgery. The cytologic characteristics of this neoplasm are described. Electron microscopy disclosed numerous zymogen granules in the tumor while histochemistry demonstrated the presence of elastase-1. Serum elastase-1 levels were markedly elevated. The cytologic differential diagnosis of pancreatic tumors is discussed. 相似文献
54.
Close linkage of MEN2A with RBP3 locus in Japanese kindreds 总被引:7,自引:0,他引:7
Masayuki Yamamoto Shin-ichiro Takai Tetsuro Miki Kazuyoshi Motomura Makoto Okazaki Isamu Nishisho Hideo Tateishi Akira Miyauchi Tasuku Honjo A. J. Pakstis Takesada Mori 《Human genetics》1989,81(3):287-288
Summary The gene responsible for multiple endocrine neoplasia type 2A (MEN2A) has recently been assigned to the pericentromeric region of chromsome 10 in European Caucasian kindreds by linkage analysis using a DNA marker, interstitial retinol-binding protein 3 (RBP3). We have found tight linkage between the MEN2A and RBP3 loci in Japanese MEN2A kindreds. The maximum lod score is 5.19 at a recombination fraction of 0.00. This result suggests that mutation of a certain gene close to RBP3 is responsible for MEN2A irrespective of ethnic backgrounds. 相似文献
55.
Ikuo Saiki Hiroaki Maeda Jun Murata Nobuchika Yamamoto Makoto Kiso Akira Hasegawa Ichiro Azuma 《Cancer immunology, immunotherapy : CII》1989,30(3):151-157
Summary We have investigated the effect of endogenous production of tumor necrosis factor (TNF) induced by the combination of recombinant interferon (rIFN) as a primer followed by GLA-60 as a trigger (rIFN/GLA-60) on murine lung metastases caused by B16-BL6 melanoma. In order to examine the therapeutic effect of endogenous TNF on tumor metastasis, the ability of multiple administrations of rIFN/GLA-60 to induce TNF production was also tested. The multiple administrations of rIFN/GLA-60 at intervals of 2 days were effective for the induction of endogenous TNF in mice but continuous multiple administrations of them for 2–4 days were not. In tumor-bearing mice, the production of endogenous TNF by rIFN/GLA-60 was less than that of normal mice, but treatment 3 days after the surgical excision of primary tumors showed the endogenous TNF production to be similar to that in normal mice. In the experimental lung metastasis model, intravenous administration of rIFN followed by intravenous or intranasal administration of GLA-60 showed potent inhibition of lung metastases of B16-BL6 melanoma, whereas the reverse sequence of administration (GLA-60/rIFN) or administration of a mixture of rIFN and GLA-60, which cannot induce the production of TNF, caused no inhibition of lung metastases. These results indicated that the regression of tumor metastases by rIFN/GLA-60 was mediated by the production of endogenous TNF in addition to the direct effects of both immunostimulants. Furthermore, the administration of rIFN and GLA-60 significantly inhibited the tumor metastases in spontaneous lung metastasis model. These results may provide a promising approach for the treatment of cancer metastasis as a result of its ability to induce endogenous TNF. 相似文献
56.
M Ishihara D J Tyrrell M C Kiefer P J Barr S J Swiedler 《Analytical biochemistry》1992,202(2):310-315
A simple panning procedure that allows for the evaluation of interactions between various heparin-like molecules and basic FGF has been developed. This assay measures the ability of compounds to inhibit the interaction of transfected human lymphoblastoid cells, UC 729-6 (UC cells), expressing hamster syndecan and basic FGF-coated plastic plates. The transfected cells bind rapidly to basic FGF-coated plates while the control cells do not bind well. Binding of the transfected cells to basic FGF was inhibited by heparin and heparin sulfate (HS), but not by chondroitin sulfate, dermatan sulfate, keratan sulfate, and hyaluronic acid. There was little inhibition of binding by chemically modified heparin such as completely desulfated, N-acetylated heparin, completely desulfated, N-sulfated heparin, and N-desulfated, N-acetylated heparin. These results suggested that both the N-sulfate and O-sulfate groups of heparin are required for binding to basic FGF. In addition, inhibition by oligosaccharides derived from depolymerized heparin increased with fragment size; partial inhibition was observed with oligosaccharides as small as hexamers. The biochemical basis for the binding of transfected cells to basic FGF was established by showing a significant increase of 35SO4 incorporation into HS. In particular, the level of 35SO4-HS in the trypsin-releasable (cell surface) pool increased fivefold. This increase was accounted for by demonstration of the presence of HS on immunoprecipitated syndecan from the transfected cells. 相似文献
57.
J L Lin T Asano H Katagiri K Tsukuda H Ishihara K Inukai Y Yazaki Y Oka 《Biochemical and biophysical research communications》1992,184(2):865-870
We engineered the GLUT1 cDNA to delete C-terminal 12 amino acids of encoded GLUT1 protein. This mutated GLUT1 protein expressed in CHO cells by transfection of its cDNA was demonstrated to reside on the plasma membrane by cell surface labeling technique, and retain the transport activity, similar to that of the wild-type GLUT1. In addition, metabolic labeling of the intact cells with 35S indicated that the half-life of the mutated GLUT1 was not significantly different from that of the wild-type GLUT1. These results suggest that C-terminal 12 amino acids of GLUT1 are not important for the transport activity and the stability of the protein. Taken together with our previous results on the mutant without C-terminal 37 amino acids, the amino acids between the 37th and the 13th from the C-terminus appear to be essential for the transport activity. 相似文献
58.
Summary ExposingBacillus
subtilis cultures to high concentrations of alkali cations, especially K+, allows efficient transformation by plasmids. The method allows transformation with unfractionated plasmid DNA, monomeric plasmid DNA as well as linear plasmid DNA.B.
subtilis strains, not amenable to natural transformation, were also transformed by the present method. 相似文献
59.
Movement of the fluvial form of red-spotted masu salmon (1+ and older),Oncorhynchus masou rhodurus, was studied using mark-recapture methods in a Japanese mountain stream. Most (63–91%) adult salmon were recaptured in the
pool in which they were marked. The rest of the salmon moved upstream or downstream <20m during the non-breeding period. The
proportion of the salmon moving increased slightly during the breeding period, but did not exceed 66%. The distance moved
was also more variable during this period. The proportion of the smaller salmon which moved was larger than that of the larger
fish during the non-breeding period. Conversely, during the breeding period, larger fish moved more frequently. Sedentary
behaviour and local movements of adult salmon seem to be affected by their social relationships. 相似文献
60.
The present study investigated the way a wild bruchid, Kytorhinus sharpianus, distributes its eggs on host pods. First, we counted the number of eggs per pod on the host plant (Sophola flavescens) in the field. The egg-distributions by the overwintered-generation adults in July and by the second-generation adults in mid October did not deviate from Poisson distribution because of small numbers of eggs laid. However, the egg-distribution in late August when many first-generation adults emerged was significantly contagious. The deposition of eggs was determined for three types of pods: (A) clean pods, (B) pods with eggs, and (C) those which eggs had been laid on but were removed from later. The numbers of eggs laid newly on three types of pods were significantly different; A>C>B, suggesting that an oviposition marker pheromone (O.M.P.) caused females to avoid pods on which eggs were deposited. Egg-shells reinforced that response. Monte Carlo simulations for the egg-distribution on pods predicted that even if females avoid pods with heavy egg-load through O.M.P., the egg-distribution becomes contagious when there is a large heterogeneity in quality of the pods. 相似文献