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61.
Tanaka G Kanaji S Hirano A Arima K Shinagawa A Goda C Yasunaga S Ikizawa K Yanagihara Y Kubo M Kuriyama-Fujii Y Sugita Y Inokuchi A Izuhara K 《International immunology》2005,17(6):797-805
It is widely known that IL-4 and IL-13 act on various kinds of cells, including B cells, resulting in enhancement of proliferation, class switching to IgE and expression of several surface proteins. These functions are important for the recognition of the various antigens in B cells and are known to be involved in the pathogenesis of allergic diseases. However, it has not been known whether IL-4/IL-13 is involved in the metabolism of various kinds of xenobiotics including 2,3,7,8-tetra-chlorodibenzo-p-dioxin (TCDD), and it remains undetermined whether TCDD, an environmental pollutant, influences IgE production in B cells, exaggerating allergic reactions. We identified IL-4- or IL-13-inducible genes in a human Burkitt lymphoma cell line, DND-39, using microarray technology, in which the AHR gene was included. The AHR gene product, the aryl hydrocarbon receptor (AhR), was induced by IL-4 in both mouse and human B cells in a STAT6-dependent manner. IL-4 alone had the ability to translocate the induced AhR to the nuclei. TCDD, a ligand for AhR, rapidly degraded the induced AhR by the proteasomal pathway, although IL-4-activated AhR sustained its expression. AhR activated by IL-4 caused expression of a xenobiotic-metabolizing gene, CYP1A1, and TCDD synergistically acted on the induction of this gene by IL-4. However, the induction of AhR had no effect on IgE synthesis or CD23 expression. These results indicate that the metabolism of xenobiotics would be a novel biological function of IL-4 and IL-13 in B cells, whereas TCDD is not involved in IgE synthesis in B cells. 相似文献
62.
Shirai Y Hashimoto M Kato R Kawamura YI Kirikae T Yano H Takashima J Kirihara Y Saito Y Fujino MA Dohi T 《Journal of clinical immunology》2004,24(1):42-52
Despite the huge number of colonized Gram-negative bacteria in the colon, the normal colon maintains its homeostasis without any excessive immune response. To investigate the potential mechanisms involved, human colonic lamina propria mononuclear cells (LPMCs) obtained from uninflamed mucosa were cultured with lipopolysaccharide (LPS) prepared from Bacteroides vulgatus (BV-LPS) or Bacteroides fragilis (BF-LPS), as representatives of indigenous flora, or pathogenic Salmonella minnesota (SM-LPS). Colonic LPMCs failed to produce inflammatory cytokines in response to any type of LPS. Colonic macrophages barely expressed mRNA for MD-2, an essential association molecule for LPS signaling via Toll-like receptor 4. Further, BV-LPS induced CD25 and Foxp3 expression in lymphocytes and CD4(+)CD25(+) cells expressed IL-10 mRNA. Thus, the low expression of functioning LPS receptor molecules and induction of IL-10-producing CD4(+)CD25(+) lymphocytes by indigenous LPS may play a central role in the maintenance of colonic immunological homeostasis. 相似文献
63.
Fujita M Ishihara M Simizu M Obara K Ishizuka T Saito Y Yura H Morimoto Y Takase B Matsui T Kikuchi M Maehara T 《Biomaterials》2004,25(4):699-706
Addition of various heparinoids to the lactose-introduced, water-soluble chitosan (CH-LA) aqueous solution produces an injectable chitosan/heparinoid hydrogel. In the present work, we examined the capability of the chitosan/non-anticoagulant heparin (periodate-oxidized (IO(4)-) heparin) hydrogel to immobilize fibroblast growth factor (FGF)-2, as well as the controlled release of FGF-2 molecules from the hydrogel in vitro and in vivo. The hydrogel was biodegraded in about 20 days after subcutaneous injection into the back of a mouse. When the FGF-2-incorporated hydrogel was subcutaneously injected into the back of both mice and rats, a significant neovascularization and fibrous tissue formation were induced near the injected site. These results indicate that the controlled release of biologically active FGF-2 molecules is caused by biodegradation of the hydrogel, and that subsequent induction of the vascularization occurs. 相似文献
64.
CD44 variant 6 in endometrioid carcinoma of the uterus: its expression in the adenocarcinoma component is an independent prognostic marker 总被引:10,自引:0,他引:10
Hoshimoto K Yamauchi N Takazawa Y Onda T Taketani Y Fukayama M 《Pathology, research and practice》2003,199(2):71-77
The expression of variant isoforms of CD44 (CD44v) correlates with the metastatic potential of various carcinomas. In endometrial cancer, however, the significance of CD44v-expression as a prognostic indicator has not been fully investigated, nor has it been compared with that of p53, estrogen receptor or Ki67. Surgical material consisted of 14 atypical endometrial hyperplasias (AEH) and 163 endometrial carcinomas (EC). Expression of CD44s, v3 and v6 in carcinoma tissue, and other prognostic markers were immunohistochemically evaluated. The expression in the squamous differentiation was strictly excluded for the evaluation of immunohistochemistry, because the significance was different from that in the adenocarcinoma component. CD44s was frequently expressed in AEH and EC. On the other hand, CD44v3- and v6-positivities were rare or nonexistent in AEH, but were observed in 8 and 35% of EC, respectively. CD44v3-expression correlated significantly with histologic grade and lymph node metastasis. However, there was no correlation between CD44v6 expression and any clinicopathologic factor, nor were other prognostic markers expressed. Univariate analysis revealed that each CD44 was a prognostic determinant in the patients with EC. However, employing multivariate analysis, there were only three independent factors: p53 overexpression, CD44v6 expression and myometrial invasion. CD44v6 expression in the adenocarcinoma component may directly affect the behavior of carcinoma and the prognosis of patients with EC. 相似文献
65.
Morita Y Ujike H Tanaka Y Uchida N Nomura A Ohtani K Kishimoto M Morio A Imamura T Sakai A Inada T Harano M Komiyama T Yamada M Sekine Y Iwata N Iyo M Sora I Ozaki N Kuroda S 《Neuroscience letters》2005,376(3):182-187
Genetic contributions to the etiology of substance abuse and dependence are topics of major interest. Acute and chronic cannabis use can produce drug-induced psychosis resembling schizophrenia and worsen positive symptoms of schizophrenia. The endocannabinoid system is one of the most important neural signaling pathways implicated in substance abuse and dependence. The fatty acid amide hydrolase (FAAH) is a primary catabolic enzyme of endocannabinoids. To clarify a possible involvement of FAAH in the etiology of methamphetamine dependence/psychosis or schizophrenia, we examined the genetic association of a nonsynonymous polymorphism of the FAAH gene (Pro129Thr) by a case-control study. We found no significant association in allele and genotype frequencies of the polymorphism with either disorder. Because the Pro129Thr polymorphism reduces enzyme instability, it is unlikely that dysfunction of FAAH and enhanced endocannabinoid system induce susceptibility to either methamphetamine dependence/psychosis or schizophrenia. 相似文献
66.
Kohno R Toyono T Seta Y Kataoka S Yamaguchi K Toyoshima K 《Archives of histology and cytology》2005,68(4):235-241
Synapses between taste receptor cells and primary sensory afferent fibers transmit the output signal from taste buds to the central nervous system. The synaptic vesicle cycle at the synapses involves vesicle docking, priming, fusion, endocytosis, and recycling. Many kinds of synaptic vesicle proteins participate in synaptic vesicle cycles. One of these, synaptotagmin 1, binds Ca(2+) phospholipids with high affinity and plays a role in Ca(2+) regulated neurotransmitter release in the central and peripheral nervous systems. However, the expression patterns of synaptotagmin 1 in rat taste tissues have not been determined. We therefore examined the expression patterns of synaptotagmin 1 and several cell specific markers of type II and III cells in rat taste buds. RT-PCR assay showed that synaptotagmin 1 mRNA was expressed in circumvallate papillae. In fungiform, foliate, and circumvallate papillae, the antibody against synaptotagmin 1 yielded the labeling of a subset of taste bud cells and intra- and subgemmal nerve processes. Double labeled experiments showed that synaptotagmin 1 positive cells co-expressed type III cell markers, PGP 9.5, and NCAM. Intragemmal nerve processes positive for synaptotagmin 1 co-expressed PGP 9.5. Conversely, all synaptotagmin 1 expressing cells did not co-expressed type II cell markers, PLCbeta2, or gustducin. These results show that synaptotagmin 1 may play some regulatory roles in vesicle membrane fusion events with the plasma membrane at the synapses of type III cells in rat taste buds. 相似文献
67.
Seminoma in a postmenopausal woman with a Y;15 translocation in peripheral blood lymphocytes and a t(Y;15)/45,X Turner mosaic pattern in skin fibroblasts.
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N Hoshi M Fujita M Mikuni T Fujino K Okuyama Y Handa H Yamada T Sagawa H Hareyama Y Nakahori K Fujieda J A Kant K Nagashima S Fujimoto 《Journal of medical genetics》1998,35(10):852-856
We report an unusual case of a 55 year old Japanese woman with a seminoma but relatively normal menses. The patient was a phenotypic female with late onset menarche (18 years of age), who was amenorrhoeic for the first year, followed by menses of one to three days' slight flow with dysmenorrhoea, but an otherwise normal menstrual history. A typical seminoma was removed from the left adnexal region and an immature testis was identified separately as an associated right adnexal mass. Repeated karyotypic studies on peripheral blood lymphocyte cultures showed only 46,X,-Y,t(Y;15)(q12;p13). Cytogenetic examination of the patient's younger brother, who had fathered three healthy children, showed an identical karyotype. Mosaicism of 46,X,-Y,t(Y;15)(q12;p13)/45,X cell lines was found in skin samples from the patient's elbow and genital regions, although there were no clinical stigmata of Turner syndrome. An androgen receptor binding assay of cultured genital skin fibroblasts was negative. Molecular analysis using Southern blot hybridisation, PCR, and direct DNA sequencing showed that neither the patient nor her brother had a detectable deletion or other abnormalities of Y chromosome sequences, including the SRY (sex determining region of the Y chromosome) gene sequence. These findings suggest that Turner mosaicism of the 45,X cell line may have contributed to this atypical presentation in an XY female, although we cannot exclude abnormalities of other genes related to sex differentiation. 相似文献
68.
Polycystic ovarian syndrome was induced in adult rats by treatment with continuous illumination to study follicular atresia.
Granulosa cells of regressing antral follicles showed characteristic features of apoptosis ultrastructurally: condensed nuclei,
apoptotic bodies, and phagocytosis of the apoptotic cells and their fragments by neighboring cells. In this study, moreover,
it was observed that an intact granulosa cell was able to ingest another granulosa cell of normal appearance, presumably indicating
an early stage of follicular atresia. The phagocytosing granulosa cell surrounded another granulosa cell to be phagocytosed
by elongated cell processes. Gap junctions developed between the phagocytic cell and the phagocytosed cell. The phagocytic
cell possessed abundant free ribosomes, well-developed rough endoplasmic reticulum and mitochondria, but few lysosomes. The
ingested cell was similar in appearance to the phagocytic cell. In addition, granulosa cells were also observed ingesting
karyopyknotic cells and degenerative organelles, both displayed in large vacuoles filled with fragments of nuclei and organelles.
These findings suggest a process of apoptosis in the granulosa cells during follicular atresia.
This study was presented at the 20th Annual Meeting of the Clinical Electron Microscopy Society of Japan, Fukuoka, September
1–3, 1988. 相似文献
69.
Therapeutic effect of topical administration of SN50, an inhibitor of nuclear factor-kappaB, in treatment of corneal alkali burns in mice 总被引:1,自引:0,他引:1
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Saika S Miyamoto T Yamanaka O Kato T Ohnishi Y Flanders KC Ikeda K Nakajima Y Kao WW Sato M Muragaki Y Ooshima A 《The American journal of pathology》2005,166(5):1393-1403
We evaluated the therapeutic efficacy of topical administration of SN50, an inhibitor of nuclear factor-kappaB, in a corneal alkali burn model in mice. An alkali burn was produced with 1 N NaOH in the cornea of C57BL/6 mice under general anesthesia. SN50 (10 microg/microl) or vehicle was topically administered daily for up to 12 days. The eyes were processed for histological or immunohistochemical examination after bromodeoxyuridine labeling or for semi-quantification of cytokine mRNA. Topical SN50 suppressed nuclear factor-kappaB activation in local cells and reduced the incidence of epithelial defects/ulceration in healing corneas. Myofibroblast generation, macrophage invasion, activity of matrix metalloproteinases, basement membrane destruction, and expression of cytokines were all decreased in treated corneas compared with controls. To elucidate the role of tumor necrosis factor (TNF)-alpha in epithelial cell proliferation, we performed organ culture of mouse eyes with TNF-alpha, SN50, or an inhibitor of c-Jun N-terminal kinase (JNK) and examined cell proliferation in healing corneal epithelium in TNF-alpha-/- mice treated with SN50. An acceleration of epithelial cell proliferation by SN50 treatment was found to depend on TNF-alpha/JNK signaling. In conclusion, topical application of SN50 is effective in treating corneal alkali burns in mice. 相似文献
70.
Yuji Okuyama Mitsuhiko Yamada Chikako Kondo Eisaku Satoh Shojiro Isomoto Takashi Shindo Yoshiyuki Horio Masafumi Kitakaze Masatsugu Hori Y. Kurachi 《Pflügers Archiv : European journal of physiology》1998,435(5):595-603
The effects of potassium channel opening drugs and intracellular nucleotides on the ATP-sensitive K+ (KATP) channel composed of SUR2A and Kir6.2 in HEK293T cells were examined using the patch-clamp technique. The SUR2A/Kir6.2 channel
was activated effectively by pinacidil, marginally by nicorandil but not by diazoxide. The pinacidil-activated channel currents
were inhibited by glibenclamide with a K
i value of 160 nM. Upon formation of inside-out (I-O) patches, spontaneous openings of the channels appeared, which were inhibited
by intracellular ATP (ATPi) equipotently in the presence and in the absence of intracellular Mg2+ (Mg2+
i). The channel activity ran-down gradually in I-O patches. The run-down channels could be reactivated by ATPi only in the presence of Mg2+
i. Uridine 5’-diphosphate (UDP) antagonized the ATPi-mediated inhibition of the channel activity before run-down. After run-down, UDP activated the channel without antagonizing
ATPi-mediated channel inhibition. Thus, the SUR2A/Kir6.2 reproduced the major properties of the native cardiac KATP channel well in terms of nucleotide regulation and pharmacology, and therefore can be a useful tool with which to elucidate
the molecular mechanisms characterizing the KATP channel.
Received: 24 October 1997 / Received after revision and accepted: 4 December 1997 相似文献