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71.
Cold-adaptation of human rotavirus 总被引:2,自引:0,他引:2
S Matsuno S Murakami M Takagi M Hayashi S Inouye A Hasegawa K Fukai 《Virus research》1987,7(3):273-280
A human rotavirus strain was cold-adapted for possible future use as a live vaccine. The original strain was isolated in 1980 in primary cynomolgus monkey kidney cells and has a serotype I and subgroup II antigenicity. The virus was serially passaged in African green monkey kidney cells; it was cultivated at 37 degrees C at the first stage of passages, and the cultivation temperature was then shifted down stepwise by 3 degrees C per each 10 passages. Finally the virus was passaged 10 times at 25 degrees C (total passage number of 55). The virus formed small-size plaques with irregular shaped borders at 31 degrees C. Growth at 25 degrees C of the cold-adapted virus was higher than that of the original virus. There was no difference between the migration patterns of 11 dsRNA segments in polyacrylamide gel electrophoresis of the original and the cold-adapted viruses. 相似文献
72.
A 56-year-old Japanese man with a malignant lymphoma of the parotid gland was reported. The tumor was located in the superficial lobe of the parotid gland, and somewhat invaded the surrounding soft tissues, but the regional lymph nodes were not involved. Histologically, the tumor was composed of round cells with plasmacytoid configurations and small lymphocytes. The plasmacytoid cells showed eccentric nuclei with fairly marked irregularities and perinuclear halos. In a large number of tumor cells, a monoclonal cytoplasmic immunoglobulin (CIg), IgG-Kappa type, was demonstrated by the PAP method. Ultrastructurally, some of the tumor cells showed welldeveloped endoplasmic reticulum. From these findings, this tumor was diagnosed as a diffuse B-cell lymphoma, mainly composed of lymphoplasmacytoid cells. And this tumor may bear a similar nature to an extramedullary plasmacytoma of the classical terminology. Malignant lymphoma of the parotid gland is rare but a case with the demonstration of monoclonal CIg is considered very rare. ACT A PATHOL. JPN. 34: 1459–1467, 1984. 相似文献
73.
Dr. S. Shiosaka M. Tohyama H. Takagi Y. Takahashi Y. Saitoh T. Sakumoto H. Nakagawa N. Shimizu 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1980,39(4):377-388
Summary The ascending and descending components of the medial forebrain bundle (MFB) were investigated by means of horseradish peroxidase (HRP) with a sensitive substrate. The HRP was injected iontophoretically into the MFB at various levels from the anterior commissure to the posterior hypothalamus. In order to prevent the diffusion of HRP to other brain areas, a double micropipette system was used. The descending components of the MFB are derived from (1) the anterior cingulate area, infra- or prelimbic area, and sulcal cortex, (2) the lateral septal nucleus and diagonal band, (3) the bed nucleus of the stria terminalis, (4) the paraventricular nucleus (5) the substantia innominata, (6) the amygdaloid complex (AM), (7) the ventromedial (VM) and dorsomedial (DM) hypothalamic nuclei, (8) the entopeduncular nucleus and (9) nucleus periventricularis stellatocellularis. The ascending components of the MFB originate in: (1) the medial preoptic nucleus, (2) the nucleus periventricularis stellatocellularis and rotundocellularis, (3) the posterior hypothalamic nucleus, (4) the parafascicular nucleus, (5) the ventral premammillary nucleus, (6) the substantia grisea periventricularis, (7) the lateral habenular nucleus, (8) the VM and DM, (9) the paratenial nucleus, (10) the AM and (11) the arcuate nucleus.Abbreviations used in Figures and Tables a
nucleus accumbens
- abl
nucleus amygdaloideus basalis, pars lateralis
- abm
nucleus amygdaloideus basalis, pars medialis
- ac
nucleus amygdaloideus centralis
- AC
anterior cingulate area
- al
nucleus amygdaloideus lateralis
- am
nucleus amygdaloideus medialis
- ar
nucleus arcuatus
- CC
tractus corporis callosi
- CSDV
commissura supraoptica dorsalis, pars ventralis
- DB
diagonal band
- DM
nucleus dorsomedialis hypothalami
- EP
nucleus entopeduncularis
- ha
nucleus anterior hypothalami
- hl
nucleus lateralis hypothalami
- hp
nucleus posterior hypothalami
- IL
infralimbic area of frontal cortex
- lh
nucleus habenulae lateralis
- LH1
medial forebrain bundle (MFB) at the level of commissura anterior
- LH2
lateral preoptic area
- LH3
MFB at the level of the nucleus anterior hypothalami
- LH4
MFB at the level of the nucleus ventromedialis hypothalami
- LH5
MFB at the level of the nucleus posterior hypothalami
- MFB
medial forebrain bundle
- pf
nucleus parafascicularis
- PL
prelimbic area of frontal cortex
- pol
nucleus preopticus lateralis
- pom
nucleus preopticus medialis
- posc
nucleus preopticus, pars suprachiasmatica
- pt
nucleus parataenialis
- pv
nucleus premamillaris ventralis
- PV
nucleus paraventricularis
- pvs
nucleus periventricularis stellatocellularis
- pvr
nucleus periventricularis rotundocellularis
- SC
sulcal cortex
- SGPV
substantia grisea periventricularis
- SI
substantia innominata
- SL
lateral septal nucleus
- ST
bed nucleus of stria terminalis
- sum
nucleus supramamillaris
- TO
tractus opticus
- tmm
nucleus medialis thalami, pars medialis
- VM
nucleus ventromedialis hypothalami
The nomenclature used in this paper is according to König and Klippel's Stereotaxic Atlas (1967). 相似文献
74.
Opioid kappa-agonists had much more potent inhibitory effects on the high K+-evoked Met-enkephalin release from rat brain slices than did the mu- or delta-agonists. The opioid kappa- antagonist, MR2266 enhanced the evoked release of Met-enkephalin to a greater extent than did mu- or delta-antagonists in vitro and had a potent analgesia in mice in vivo. These findings suggest that the release of Met-enkephalin may be regulated in vitro and in vivo, mainly by presynaptic kappa-receptor-mediated mechanisms. 相似文献
75.
Kenji Hanabusa Jun-ichi Higashi Toshiki Koyama Hirofusa Shirai Nobumasa Hojo Akio Kurose 《Macromolecular chemistry and physics.》1989,190(1):1-8
New thermotropic, liquid-crystalline polyesters ( 5a, b, 6a, b ) with mesogenic bipyridinediyl units were synthesized. They form complexes with Fe(II) and Cu(II) salts. Homopolyesters 5a, b , containing no metal or less than a certain amount of metal, are smectic. A nematic mesophase was observed in the case of copolyester 6a, b . The structural properties of a polyester complex 5a with Cu, as crystal, liquid-crystal and isotropic liquid, were examined by ESR. 相似文献
76.
Ghrelin Induces Fasted Motor Activity of the Gastrointestinal Tract in Conscious Fed Rats 总被引:15,自引:1,他引:15
Kazunori Fujino Akio Inui† Akihiro Asakawa† Naoki Kihara Masaki Fujimura Mineko Fujimiya‡ 《The Journal of physiology》2003,550(1):227-240
Ghrelin is a newly discovered orexigenic peptide originating from the stomach. However, its action in regulating the fed and fasted motor activity of the digestive tract is not fully understood. In the present study, we examined the effects of intracerebroventricular ( i.c.v. ) and intravenous ( i.v. ) injection of ghrelin on the physiological fed and fasted motor activities in the stomach and duodenum of freely moving conscious rats. i.c.v. and i.v. injection of ghrelin induced fasted motor activity in the duodenum in normal fed rats, while i.v. injection of ghrelin induced fasted motor activity in both the stomach and duodenum in vagotomized rats. The effects of i.c.v. and i.v. injected ghrelin were blocked by growth hormone secretagogue receptor (GHS-R) antagonist given by the same route and also blocked by immunoneutralization of neuropeptide Y (NPY) in the brain. The effects of i.v. injected ghrelin were not altered by i.c.v. injection of GHS-R antagonist in vagotomized rats. Injection of GHS-R antagonist blocked the fasted motor activity in both the stomach and duodenum in vagotomized rats but did not affect the fasted motor activity in normal rats. Low intragastric pH inhibited the effect of ghrelin. The present results indicate that ghrelin is involved in regulation of fasted motor activity in the stomach and duodenum. Peripheral ghrelin may induce the fasted motor activity by activating the NPY neurons in the brain, probably through ghrelin receptors on vagal afferent neurons. Once the brain mechanism is eliminated by truncal vagotomy, ghrelin might be primarily involved in the regulation of fasted motor activity through ghrelin receptors on the stomach and duodenum. The action of ghrelin to induce fasted motor activity is strongly affected by intragastric pH; low pH inhibits the action. 相似文献
77.
A pharmacological and histological examination of the microcirculation of the rat subcutaneous air-pouch: microcirculation of the rat air-pouch 总被引:1,自引:0,他引:1
The effects of histamine, 5-hydroxytryptamine (5-HT) and prostaglandin E2 (PGE2) on plasma protein extravasation in the rat subcutaneous air-pouch have been studied. Both histamine and 5-HT produced increases in plasma protein extravasation which were inhibited by specific receptor antagonists. Plasma protein extravasation induced by PGE2 was partially inhibited by either a 5-HT receptor antagonist (methysergide) or by a combination of H1 and H2 receptor antagonists (mepyramine and cimetidine). A combination of all three antagonists further reduced plasma protein extravasation. These results suggest that PGE2 increases vascular permeability indirectly via the degranulation of mast cells. This supposition was confirmed by histological evidence of extensive mast cell degranulation following the injection of PGE2 but not following histamine, 5-HT or saline injection. Using a technique of vascular labelling, following the intravenous injection of Monastral blue dye, plasma extravasation induced by histamine, 5-HT or PGE2 was observed to be restricted to post-capillary venules and was not observed in arterioles or capillaries. Electron microscopic examination of the tissue revealed the presence of monastral blue particles trapped between endothelial cells. These findings suggest that the microcirculation of the rat subcutaneous air-pouch behaves in an analogous manner to that of other tissues. 相似文献
78.
Takayama H Takagi H Larochelle WJ Kapur RP Merlino G 《Laboratory investigation; a journal of technical methods and pathology》2001,81(3):297-305
Hepatocyte growth factor/scatter factor (HGF/SF) can stimulate growth of gastrointestinal epithelial cells in vitro; however, the physiological role of HGF/SF in the digestive tract is poorly understood. To elucidate this in vivo function, mice were analyzed in which an HGF/SF transgene was overexpressed throughout the digestive tract. Nearly a third of all HGF/SF transgenic mice in this study (28 of 87) died by 6 months of age as a result of sporadic intestinal obstruction of unknown etiology. Enteric ganglia were not overtly affected, indicating that the pathogenesis of this intestinal lesion was different from that operating in Hirschsprung's disease. Transgenic mice also exhibited a rectal inflammatory bowel disease (IBD) with a high incidence of anorectal prolapse. Expression of interleukin-2 was decreased in the transgenic colon, indicating that HGF/SF may influence regulation of the local intestinal immune system within the colon. These results suggest that HGF/SF plays an important role in the development of gastrointestinal paresis and chronic intestinal inflammation. HGF/SF transgenic mice may represent a useful model for the study of molecular mechanisms associated with a subset of IBD and intestinal pseudo-obstruction. Moreover, our data identify previously unappreciated side effects that may be encountered when using HGF/SF as a therapeutic agent. 相似文献
79.
80.
K. Taniguchi H. Tsuchie S. Kageyama M. Iwasaki T. Takagi F. Sasao S. Ueda T. Kurimura 《Archives of virology》1998,143(5):881-890
Summary. HIV-1 p17 antigen has been studied for its biological significance in vitro as well as its immunological roles in vivo. By
immunological approach of antibody-binding to HIV-1 p17 antigens of several subtypes in combination with computerized analysis
of those tertial structures, it became evident that, irrelevant of similarity of linear amino acid sequence of different HIV-1
subtypes, a few amino acid substitutions close to or distant from specified epitope(s) affected their tertial structure resulting
in change in ability of its binding to selected antibody. ELISA employing two monoclonal antibodies, A144 and C415, could
detect p17 of subtypes A and B, but not of subtypes C, D, and E. Since the epitope site corresponding to A144 has been reported
to be important for biological activity of p17 of HIV-1, change in tertial structure around this epitope may explain some
difference in biology of HIV-1, such as infectivity of subtypes B and E.
Accepted January 9, 1998 Received October 24, 1997 相似文献