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381.
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383.
Y. Inamori Y. Kuniyasu N. Hayashi H. Ohtake R. Sudo 《Applied microbiology and biotechnology》1990,34(3):404-407
Summary
Philodina erythrophthalma (an euryphagous Rotatoria) and Aeolosoma hemprichi (a stenophagous Oligochaeta), isolated from a waste-water treatment process, were grown in monoxemic and mixed cultures using a variety of bacterial species as prey. In monoxenic cultures, P. erythrophthalma could grow by feeding on a wide range of bacterial species, while A. hemprichi exhibited a relatively high prey specificity. The growth rates of P. erythrophthalma and A. hemprichi increased in the mixed culture, compared with those in the respective monoxenic cultures. Interestingly, the sizes of bacterial flocs were observed to increase in the presence of P. erythrophthalma. On the basis of the experimental results, the role of metazoa in a waste-water purification process is discussed.
Offprint requests to: Y. Inamori 相似文献
384.
S. Yamamoto Hiroki Abe Toshiaki Kohgo Atushi Ogawa Akira Ohtake Hidemasa Hayashibe Hitoshi Sakuraba Yoshiyuki Suzuki Shuichi Aramaki Masaki Takayanagi Shuji Hasegawa Hiroo Niimi 《Human genetics》1996,98(1):116-118
Carnitine palmitoyltransferase II (CPT II) deficiency has two different clinical forms, one with “hepatic” and the other
with “muscular” symptoms. We studied the molecular basis of the “hepatic” form in two Japanese siblings. Their CPT II activity
in lymphoblasts was reduced to 3% of the level observed in normal controls. cDNA analysis showed that the proband was a compound
heterozygote. One allele carried a new mutation, G621→A (Glu174→Lys). The other carried three single-base substitutions; a
new mutation, T1249→A (Phe383→Tyr), and two previously reported polymorphisms. The brother had the same four substitutions.
Neither of the two new mutations in this study was detected in the 60 alleles of 30 Japanese control subjects. Secondary structure
prediction analysis of the mutated CPT II protein was different from that of the normal protein. We concluded that these mutations
caused the “hepatic” form of CPT II deficiency in the probands.
Received: 16 October 1995 相似文献
385.
The complete mitochondrial DNA sequence of the shark Mustelus manazo: evaluating rooting contradictions to living bony vertebrates 总被引:5,自引:0,他引:5
A remarkable example of a misleading mitochondrial protein tree is
presented, involving ray-finned fishes, coelacanths, lungfishes, and
tetrapods, with sea lampreys as an outgroup. In previous molecular
phylogenetic studies on the origin of tetrapods, ray-finned fishes have
been assumed as an outgroup to the tetrapod/lungfish/coelacanth clade, an
assumption supported by morphological evidence. Standard methods of
molecular phylogenetics applied to the protein-encoding genes of
mitochondria, however, give a bizarre tree in which lamprey groups with
lungfish and, therefore, ray-finned fishes are not the outgroup to a
tetrapod/lungfish/coelacanth clade. All of the dozens of published
phylogenetic methods, including every possible modification to maximum
likelihood known to us (such as inclusion of site heterogeneity and
exclusion of potentially misleading hydrophobic amino acids), fail to place
the ray-finned fishes in a biologically acceptable position. A likely cause
of this failure may be the use of an inappropriate outgroup. Accordingly,
we have determined the complete mitochondrial DNA sequence from the shark,
Mustelus manazo, which we have used as an alternative and more proximal
outgroup than the lamprey. Using sharks as the outgroup, lungfish appear to
be the closest living relative of tetrapods, although the possibility of a
lungfish/coelacanth clade being the sister group of tetrapods cannot be
excluded.
相似文献
386.
387.
388.
The effects of dopamine on the release of thyrotropin-releasing hormone (TRH) from the rat adrenal gland were studied in vitro. The rat adrenal glands were incubated in medium 199 with 1.0 mg/ml of bacitracin and 100 micrograms/ml of ascorbic acid (pH 7.4) (medium) for 20 min. The amount of TRH release into the medium was measured by radioimmunoassay. The immunoreactive TRH (ir-TRH) release from the rat adrenal gland was inhibited significantly in a dose-related manner with the addition of dopamine and enhanced with the addition of pimozide or domperidone to the medium. Dopamine's effects on ir-TRH release from the adrenal gland were blocked with the addition of pimozide or domperidone. The elution profile of methanol-extracted rat adrenal gland was identical to that of synthetic TRH. The findings suggest that the dopaminergic system inhibits TRH release from the rat adrenal gland. 相似文献
389.
D B Jennings J C McKirdy P J Ohtake I R Sarda T G Flynn G K Hira 《Canadian journal of physiology and pharmacology》1990,68(9):1292-1297
We have reported that a second rat atrial natriuretic peptide, iso-rANP (1-45), as well as the putative ANP homologue, iso-rANP (17-45), elicited circulatory and renal responses in the rat similar to those found after administration of ANP. Iso-rANP also interacted with ANP to potentiate the observed biological activity in the rat. In the present studies in awake dogs, intravenous infusion of low doses (6.3-50 pmol.kg-1.min-1) of iso-rANP(1-45) and iso-rANP(17-45) increased plasma immunoreactive ANP and suppressed plasma renin activity (PRA) and aldosterone. Iso-rANP, like ring-deleted analogues of ANP, may have displaced ANP from ANP clearance receptors to increase plasma ANP concentration, since factors influencing myocardial ANP release were not changed. The effect of iso-rANP (1-45) and (17-45) in lowering PRA and plasma aldosterone may therefore have been indirect, via ANP stimulation of active guanylate cyclase-linked ANP receptors. However, an additional direct effect of iso-rANP on an active receptor cannot be excluded. 相似文献
390.
Objective: Recently, we found that transglutaminase 2 (TG2) might be involved in the difference in proliferative capacities between periportal hepatocytes (PPH) and perivenous hepatocytes (PVH) through down-regulation of high-affinity epidermal growth factor receptor (EGFR). However, it is uncertain whether this high-affinity EGFR contributes to the hepatocyte growth signalling pathway. Here, we have investigated the influence of TG2 on EGF-induced EGFR dimerization and its phosphorylation, which are important steps in the hepatocyte proliferative/growth signalling pathway, in PPH and PVH.
Materials and methods: PPH and PVH were isolated using the digitonin/collagenase perfusion technique. Amounts of TG2, EGFR dimerization and its phosphorylation were determined by Western blot analysis.
Results: Pretreatment with monodansylcadaverine, an inhibitor of TG2, greatly increased EGF-induced EGFR dimerization and its phosphorylation in PVH compared with PPH. Conversely, treatment with retinoic acid, an inducer of TG2, significantly decreased EGF-induced EGFR dimerization and its phosphorylation with a significant increase in TG2 expression and its catalysed products, isopeptide bonds, in both subpopulations. It was found that EGFR served as a substrate for TG2.
Conclusion: The present data showed good correlation with our previous data on EGF-induced DNA synthesis and EGFR-binding affinity to EGF. These results suggest that zonal difference in cell growth between PPH and PVH may be caused by down-regulation of EGFR dimerization and subsequent autophosphorylation through TG2-mediated cross-linking of EGFR. 相似文献
Materials and methods: PPH and PVH were isolated using the digitonin/collagenase perfusion technique. Amounts of TG2, EGFR dimerization and its phosphorylation were determined by Western blot analysis.
Results: Pretreatment with monodansylcadaverine, an inhibitor of TG2, greatly increased EGF-induced EGFR dimerization and its phosphorylation in PVH compared with PPH. Conversely, treatment with retinoic acid, an inducer of TG2, significantly decreased EGF-induced EGFR dimerization and its phosphorylation with a significant increase in TG2 expression and its catalysed products, isopeptide bonds, in both subpopulations. It was found that EGFR served as a substrate for TG2.
Conclusion: The present data showed good correlation with our previous data on EGF-induced DNA synthesis and EGFR-binding affinity to EGF. These results suggest that zonal difference in cell growth between PPH and PVH may be caused by down-regulation of EGFR dimerization and subsequent autophosphorylation through TG2-mediated cross-linking of EGFR. 相似文献