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11.
Hepatocyte contribution to hepatic collagen production in vivo was estimated in rats, based on the fact that ornithine is used for protein synthesis in the liver as arginine after conversion by way of the urea cycle only by hepatocytes. From rats given a mixture of [14C] ornithine and [3H]arginine, hepatic collagen and serum albumin were obtained. The hepatocyte contribution was calculated from the 14C and 3H in arginine purified from collagen and albumin by high performance liquid chromatography. The contribution was less than 10% of total collagen production in normal and early fibrotic livers induced by a single dose of carbon tetrachloride or dimethylnitrosamine. We conclude that hepatocytes may play a minor role in collagen production in normal and early fibrotic rat livers. 相似文献
12.
M Ogata H Matsumoto S Shimizu S Kida T Wada M Shiro K Sato 《Journal of medicinal chemistry》1986,29(3):417-423
To find antiviral agents, various sulfonamidobenzophenone oximes (II) were synthesized from the appropriate m-sulfonamidobenzophenones by hydroxylamine reaction. The reaction products were generally obtained as syn/anti mixtures which were separable by fractional crystallization. The anti isomer had more potent antipoliovirus activity than the syn isomer. Various sulfonamidobenzamides (III) which were structurally related to II were synthesized by the reactions of amino-substituted benzamides with sulfuryl chloride or amines with (aminosulfonyl)benzoyl chloride. Antiviral activity was examined by the plaque-inhibition test. Compounds 5, 36, and 69 exhibited strong antipicornavirus activity. The structure-activity relationships are discussed. 相似文献
13.
P. Schubert T. Ogata S. Ferroni A. McRae Y. Nakamura K. Rudolphi 《Journal of molecular neuroscience : MN》1996,28(1-3):185-190
In view of the increasing evidence that a pathological glial activation plays a significant role in the development of neurodegenerative
diseases, we investigated the underlying molecular signaling as a possible target for a pharmacological therapy. Here, we
are particularly focusing on the endogenous modulation of the Ca2+ and cyclic nucleotide-dependent signaling by the nucleoside adenosine and its reinforcement by the xanthine derivative propentofylline
(PPF). As an experimental model, we used cultured rat microglial cells and astrocytes that are immature, show a high proliferation
rate, and resemble in several aspects pathologically activated glial cells. A prolonged increase of the cellular cAMP level
favored the differentiation of cultured astrocytes and associated properties required for the physiological nerve cell function.
On the other hand, a strengthening of the cyclic nucleotide-dependent signaling inhibited potentially neurotoxic properties
of cultured microglial cells. Similar effects were obtained by treatment with propentofylline, which mimicked modulatory adenosine
effects and increased the intracellular level of cAMP and cGMP. Such a pharmacological glial cell conditioning, obtained by
modifying the strength and the timing of these second messengers, may provide a therapy of neurodegenerative diseases in which
a pathological activation of microglial cells and astrocytes is discussed to play a pathogenic role. 相似文献
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16.
Okamoto T Jeong SY Takahashi Y Baughman KW Ogata K Goto J Kanazawa I 《International journal of molecular medicine》2001,8(4):413-416
Calcium channel blocker is useful for a variety of purposes and is effective for preventing hepatitis elicited by different inducers, suggesting its possible clinical application for treating hepatitis. The alpha1-subunit of the dihydropyridine-sensitive L-type calcium channel is a target of calcium channel blocker. For clinical application of calcium channel blocker, it is important to analyze the expression of the L-type calcium channel in the liver. However, the subtype of the L-type calcium channel alpha1-subunit expressed in the liver was not known. In the present study, the alpha1-subunit of the calcium channel expressed in human liver was systematically analyzed. The alpha1D subunit of the dihydropyridine-sensitive L-type voltage gated calcium channel is expressed relatively strongly in the liver and may play an important role in the liver. 相似文献
17.
Comparison of adult height between patients with XX and XY gonadal dysgenesis: support for a Y specific growth gene(s). 下载免费PDF全文
Adult height was compared between published cases of patients with XX gonadal dysgenesis (XXGD) and those with XY gonadal dysgenesis (XYGD). The mean adult height of XYGD patients (171.0 cm (SD 7.8), n = 27) was significantly greater than that of XXGD patients (164.4 cm (7.7), n = 27) (p less than 0.01). This finding supports the existence of a Y specific growth gene(s) which promotes statural growth independently of the effects of gonadal sex steroids. 相似文献
18.
Satoshi Mochida Itsuro Ogata Yasuhiko Ohta Teruaki Oka Kenji Fujiwara 《Pathology international》1991,41(3):217-220
In order to investigate superoxide production by pulmonary macrophages in the rat, a route was created by ligating both the inferior and superior venae cavae and resecting the aorta after cannulation through the inferior vena cava into the right atrium of the heart. Lung perfusion was performed via this route with nitro blue tetrazolium. Although there was no formazan deposition throughout the lung, it became detectable in both alveolar and interstitial macrophages when phorbol myristate acetate was added to the perfusate. This deposition was markedly enhanced by previous injection of Corynebacterium parvum. The deposition disappeared after further addition of Cu(Lys)2 , a scavenger of superoxide anions. This procedure may be useful for estimating in situ the ability of pulmonary macrophages to produce superoxide in the rat. 相似文献
19.
Mycobacterium avium-M. intracellulare binds to the integrin receptor alpha v beta 3 on human monocytes and monocyte-derived macrophages. 总被引:1,自引:4,他引:1 下载免费PDF全文
Mycobacterium avium-M. intracellulare is an intracellular pathogen responsible for the highest incidence of disseminated bacterial infection in patients with AIDS. Treatment of the infection is difficult and has been of limited efficacy. Attachment of the organism to macrophages is a critical early step in the establishment of the disease. In the present study, we isolated and identified a receptor that mediates attachment of M. avium-M. intracellulare to human peripheral blood monocytes and monocyte-derived macrophages. On Western blotting, (immunoblotting), the receptor was found to cross-react with antibodies against a human vitronectin receptor (alpha v beta 3). The receptor could be purified from monocyte extracts by using monoclonal antibodies (MAbs) against the alpha v subunit of vitronectin receptor coupled to CNBr-Sepharose 4B, as well as with the adhesive tripeptide sequence arginine-glycine-aspartic acid (RGD) coupled to CNBr-Sepharose 4B. Surface-bound MAbs directed against alpha v beta 3 were found to inhibit the attachment of M. avium-M. intracellulare to monocyte-derived macrophages in an in vitro inhibition assay, while MAbs directed against CD14, CD18, alpha 2 beta 1 and platelet glycoprotein gpIIb/IIIa receptors did not inhibit this attachment. These observations suggest that alpha v beta 3 on the surface of human monocytes and monocyte-derived macrophages may function as a receptor for M. avium-M. intracellulare. Identification of a receptor for M. avium-M. intracellulare on macrophages may offer new approaches to the prevention and control of M. avium-M. intracellulare infection at the cellular level. 相似文献
20.
The growth of Nocardia asteroides GUH-2 and two mutants (NG-49 and I-38-syn) in regions of the brains of BALB/c mice was determined by microdissection and viable counting. GUH-2 grew throughout the murine brain but at different growth rates that depended on the specific location. The rate of increase in total CFU per brain during GUH-2 infection was unaffected by the inoculum size; however, in five of eight brain regions, an alteration in the inoculum size resulted in altered nocardial growth rates. Mutant NG-49 showed a significantly slower rate of increase in total CFU per brain than did the parental strain, GUH-2, and significantly decreased growth rates in seven brain regions. Mutant I-38-syn showed a rate of increase in total CFU per brain similar to that of the parental strain; however, this mutant grew significantly faster in the cerebellum and pons-medulla. Growth appeared to be a necessary precursor to the cellular damage that resulted in the variety of neurological disorders observed in mice infected with N. asteroides GUH-2, because mutant NG-49 exhibited a decreased ability to grow in specific regions of the brain and did not induce signs of neurological damage. In contrast, mutant I-38-syn induced neurological signs in a larger percentage of the infected animals than did parental strain GUH-2 and grew better in certain regions of the brain than did the parental strain. Furthermore, there appeared to be a relationship between the growth of N. asteroides in the substantia nigra and the induction of an L-dopa-responsive head shake that was observed in some of the mice following a sublethal intravenous injection of N. asteroides GUH-2. 相似文献