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81.
Suzuki T Muraki Y Yasukochi T Zhang H Kori Y Wakamatsu E Hayashi T Goto D Ito S Tsutsumi A Sumichika H Sumida T Matsumoto I 《Autoimmunity reviews》2005,4(7):475-478
Anti-glucose-6-phosphate isomerase (GPI) antibodies (Abs) solely induce arthritis in mice. High titers of anti-GPI Abs are found in some patients with rheumatoid arthritis (RA), but their pathogenic role remains elusive. The aim of this study was to evaluate the pathogenic role of anti-GPI Abs in cynomolgus monkeys. IgG fractions were separated from sera of anti-GPI Abs-positive RA patients and healthy subjects and directly injected into the metacarpophalangeal joints of 4 cynomolgus monkeys. At day 16, the joints were harvested and examined histologically and immunohistochemically. The expression of C5a receptor (C5aR) molecule in the synovium was quantified by real-time PCR using cDNA from monkey joints. In monkey joints, IgG including anti-GPI Abs resulted in recruitment of granulocytes and mononuclear cells, strong deposition of human IgG on the articular surface, and overexpression of C5aR, but no joint swelling. No infiltrated cells or IgG deposition were observed in monkeys injected with IgGs from healthy subjects. Our results suggest that IgG fraction from RA patients including anti-GPI Abs may play a crucial role in the generation of synovitis in monkeys, although the pathogenesis of anti-GPI Abs in RA patients is still uncertain. 相似文献
82.
Host resistance to Listeria monocytogenes infection is enhanced but resistance to Staphylococcus aureus infection is reduced in acute graft-versus-host disease in mice
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Miura T Mizuki D Sasaki S Hasegawa S Sashinami H Nakane A 《Infection and immunity》2000,68(7):4340-4343
Acute graft-versus-host disease (GVHD) is characterized by the production of high levels of T helper 1 (Th1)-type cytokines. Bone marrow transplantation from allogeneic C57BL/6 cells to CBF(1) mice produced acute GVHD. Host resistance to Th1-driven Listeria monocytogenes was enhanced, whereas host resistance to Th2-driven Staphylococcus aureus was reduced during acute GVHD. These results suggest that opposite host responses are observed between Th1-driven and Th2-driven bacterial infections in acute GVHD. 相似文献
83.
Recently, genomic DNA of the novel TT virus (TTV) was isolated from patients suffering from posttransfusion hepatitis of unknown etiology. We examined sera from 197 children who visited the Department of Pediatrics at Toyohashi National Hospital. Sera were tested for TTV DNA by seminested polymerase chain reaction (PCR) using a set of primers synthesized according to the published TTV sequence. Ten children were found to be positive for TTV (5.1%). All positive PCR products were directly sequenced in both directions using a fluorescent dye terminator cycle sequencing system. The sequences were compared by a multiple sequence alignment and a phylogenetic tree was constructed. The phylogenetic tree showed that two of the TTV isolates found in the present experiment did not belong to any of the phylogenetic groups previously reported. 相似文献
84.
Kobayashi K Kusakabe M Okada M Sakairi T Goto K Tsuchiya T Sugimoto J Sano F Mutai M 《Toxicologic pathology》2000,28(5):664-667
Hepatocellular carcinomas (HCCs) were induced in male Fischer 344 rats with dietary 3'-methyl-4-(dimethylamino)-azobenzene treatment and were classified into solid, glandular (well- or poorly differentiated), and trabecular types. Investigation of cell proliferation kinetics and immunohistochemical localization of transforming growth factor alpha (TGF-alpha) demonstrated all solid (n = 24) and poorly differentiated glandular type (n = 6) HCCs to have TGF-alpha-positive nuclei. Nuclear staining of TGF-alpha was also observed in 13 of 28 (46%) trabecular-type HCCs, whereas 12 (43%) exhibited cytoplasmic staining, and 3 (11%) were negative. As for well-differentiated glandular HCCs, 7 of 20 (35%) were positively stained in their nucleus, another 7 (35%) demonstrated antibody binding in the cytoplasm, and 6 (30%) were negative. The order for growth rate evaluated by bromodeoxyuridine (BrdU) labeling was solid (38.22%), poorly differentiated glandular (26.82%), trabecular (7.98%), and well-differentiated glandular (2.57%) types. For trabecular HCCs with nuclear, cytoplasmic, or negative TGF reactions, values were 13.39% (n = 13), 3.61% (n = 12), and 2.01% (n = 3), respectively. Likewise, BrdU-labeling indices for the counterpart groups of well-differentiated glandular type HCCs were 4.53, 1.91, and 1.29%, respectively. The results indicate that TGF-alpha expression might be linked to histopathological differentiation and cell proliferation in rat HCCs. 相似文献
85.
Kazuei Ito Jutaro Takahashi Yasuhisa Yasuda Masahiro Takahashi Kyoko Kawahata Taichi Goto 《American journal of reproductive immunology (New York, N.Y. : 1989)》1998,39(6):356-361
PROBLEM: Early pregnancy factor (EPF) has been detected in pregnant bovine serum, and its activity appeared from 24 to 48 hr after insemination. However, in bovine in vitro fertilization (IVF), an EPF-like substance(s) had been detected in the culture medium of fertilized ovum. Therefore, we think that EPF and EPF-like substance(s) are very important materials for the development of the embryo. In this study, we examined the development of the embryo when fertilized bovine ova were cultured with IVF culture medium supplemented with EPF-positive or -negative serum. METHOD OF STUDY: EPF activity of each serum (fetal calf serum [FCS], calf serum [CS], estrus bovine serum, and pregnant bovine serum) was assessed by the bovine-rosette inhibition test. The sera were supplemented in TCM-199 culture medium, and IVF bovine ova were cultured with the media for 6 or 7 days, respectively. The culture media of each group were evaluated for EPF activity by the bovine-rosette inhibition test 48 hr after IVF. The cleavage rate of each group was calculated at 48 hr, and 6 or 7 days after IVF. The culture medium of cumulus cells was also tested for EPF activity. RESULTS: Only the pregnant bovine sera were EPF positive. All the culture media 48 hr after IVF became EPF positive. Additionally, the culture medium of cumulus cells did not have EPF activity. There was no significant difference in the cleavage rate of the EPF-positive and - negative sera 48 hr after IVF. However, the cleavage rate of EPF-positive sera tended to be higher than the negative sera. In contrast, the blastocyst development rates of EPF-positive sera were significantly higher than those of the negative sera 6 to 7 days after IVF (P < 0.05). CONCLUSIONS: The data suggest that an EPF-like substance(s) may be secreted from the in vitro fertilized bovine ovum but not from the cumulus cell, and that the EPF in the pregnant serum may accelerate the development of the bovine embryo in IVF. 相似文献
86.
S. Goto A. Hirano 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1989,77(2):442-446
Summary This report concerns the postnatal expression of calcineurin (CaN) in rat striatum. For this purpose an immunohistochemical procedure was used. In neonatal striatum CaN immunoreactivity was found in discrete patches composed of many immature cells. With development there was an increase in staining intensity and in the proportion of positively reacting cells. CaN expression and localization in the striatum of 22–25 day old rats were similar to those of adult animals. 相似文献
87.
Constitutive production of interleukin 6/B cell stimulatory factor-2 from inflammatory synovium 总被引:6,自引:0,他引:6
N Miyasaka K Sato J Hashimoto H Kohsaka K Yamamoto M Goto K Inoue T Matsuda T Hirano T Kishimoto 《Clinical immunology and immunopathology》1989,52(2):238-247
Interleukin 6 (IL-6) production from synovial tissues of various diseases was examined. Augmented IL-6 production was found in inflammatory synovium not only in RA but also in other kinds of synovitis, including psoriatic arthritis and Beh?et's disease. Increased amounts of IL-6-mRNA were detected in rheumatoid synovium using a dot blot hydridization technique. Furthermore, there was a positive correlation between IL-6 production and accumulation of plasma cells in the synovium. These findings suggest that IL-6 plays an important role not only in immune response but also in active inflammation in various kinds of synovitis. 相似文献
88.
The interaction between oxidized low-density lipoprotein (LDL) and macrophages are known to be important in the development of arteriosclerosis. Macrophages take up oxidized LDL, becoming foam cells, which contribute to the thickening of the blood vessel wall. The antioxidant properties of polyphenols found in vegetables and other foods have been shown to have a protective effect against arteriosclerosis. To elucidate the effect of flavonoids from fruits, vegetables and cereals on oxidized LDL uptake in macrophages, the inhibitory activity of various flavonoids on DiI-ac-LDL uptake reaction in mouse macrophage cell line J774.1 was measured. We found significant uptake of DiI-ac-LDL, but not DiI-LDL, into the J774.1 cells. In addition, polyinosin and dextran sulphate inhibited uptake, but apigenin, kaempferol, and naringenin, did not. Isoflavones and resveratrol significantly inhibit uptake of DiI-ac-LDL into macrophages, and have a protective effect against arteriosclerosis. 相似文献
89.
Goto F Straka H Dieringer N 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》2002,147(3):374-386
Postlesional reorganization of vestibular afferent and commissural inputs onto second-order vestibular neurons was studied
in the isolated brain after unilateral section of the N.VIII, of the ramus anterior (RA) of N.VIII, of the utricular (UT)
or of the anterior vertical and horizontal canal nerves in combination. RA nerve section eliminated the inputs from utricular,
anterior vertical and horizontal canal organs. In the first set of experiments we recorded field potentials on the operated
side of the vestibular nuclei 2 months after RA nerve section. These responses were evoked by electrical stimulation of the
RA nerve or of the posterior vertical canal nerve on the operated or on the intact side. The amplitudes of afferent field
potentials evoked by stimulation of the spared posterior vertical canal nerve were increased. The amplitudes of afferent field
potentials evoked by stimulation of the axotomized RA nerve remained unaltered. After N.VIII section the commissural, but
not the afferent, field potentials increased significantly on the operated side following stimulation of N.VIII on the intact
and on the operated side, respectively. After UT nerve section no change in commissural but an increase in the amplitude of
afferent field potentials from each of the three intact canal nerves was observed on the operated side. In the context of
earlier results these findings imply that second-order vestibular neurons, disfacilitated due to afferent nerve section, became
receptive to additional, excitatory synaptic inputs, preferentially from intact vestibular nerve afferent fibers. The reduced
excitation via afferent nerve inputs was thereby replaced by other afferent nerve inputs from spatially inadequate vestibular
end-organs. The synaptic terminals of inactivated afferent nerve fibers were maintained and not repressed. The process of
central reorganization after vestibular nerve lesion was activity related, the expansion of signals restricted to inputs from
intact fibers, its extent graded and its onset delayed with respect to the onset of corresponding spinal changes and to the
onset of postural recovery after the same type of nerve lesion. After the section of RA nerve or of an individual nerve branch
the labyrinthine end-organs remained intact and were not removed as after unilateral labyrinthectomy (UL). Peripheral reinnervation
of the end-organs was thus excluded after UL, but expected after one of the former types of lesion. Functional reinnervation
of the utricular macula was mirrored behaviorally by the reappearance of severe postural deficits following a second RA nerve
section. These lesion-induced postural deficits began to reappear if the repeated RA nerve section was delayed with respect
to the first by about 3 months. We therefore studied postlesional reorganization in the brainstem 3 months after the first
RA nerve section. Reinnervation of the utricular macula was accompanied by a rapid decline of the increased amplitudes of
afferent and commissural vestibular field potentials towards control values, suggesting the reversibility of the lesion-induced
central reorganization.
Electronic Publication 相似文献
90.