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11.
A single oral administration of orthophenylphenol (OPP, 1400 mg/kg; about half the LD50) to male Fischer 344 rats produced an elevation of serum transaminase activity 24 h later. Pretreatment with l-buthionine-S,R-sulfoximine (BSO, 900 mg/kg) in the OPP-treated rats potentiated the hepatic and renal damage which was accompanied by necrosis. Six hours after the administration of OPP (700 or 1400 mg/kg), hepatic and renal glutathione (GSH) levels decreased with increasing dosage. Hepatic GSH depletion with OPP was enhanced with BSO pretreatment and the recovery of GSH in both organs was slow in the high-dose OPP group. These results suggest that hepatic and renal damage is associated with a serious and prolonged GSH depletion. When either phenyl-p-benzoquinone (PBQ) or phenylhydroquinone (PHQ), which are intermediates of OPP, was administered orally to rats at 700 or 1400 mg/kg, the mortality with the high dose of PBQ was 75% at 24 h. The serum transaminase activity and UN level increased with the low dose of PBQ, accompanied by necrotic hepatocytes. The toxic effects of PHQ on kidney or liver were less than those on PBQ. These observations suggest that the liver and kidney may be target organs for toxic actions of a large dose of OPP and its intermediate, PBQ.Part of this work was presented at IInd International ISSX Meeting Xenobiotic Metabolism and Disposition, May 16–20, 1988, Kobe, Japan  相似文献   
12.
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   
13.
Rat incisors grow continuously throughout life. Producing a variety of dental epithelial cells is performed by stem cells located in the cervical loop of the incisor apex. To study the mechanisms for cell differentiation, we established a dental epithelial cell line (HAT-7) originating from a cervical loop epithelium of a rat incisor. Immunochemical studies showed that HAT-7 produced the cells expressing amelogenin, ameloblastin, or alkaline phosphatase (ALP). To illustrate a role of Notch signaling in the determinant of the cell fate, we examined expression patterns of Notch1 and Jagged1 in HAT-7 density dependently. At lower cell density, Notch1- or Jagged1-expressing cells were not seen. However, when they were fully confluent, cells began to express Notch1 or Jagged1 strongly. Some ALP-positive cells were almost consistent with Notch1-expressing cells but not Jagged1-expressing cells. These results suggested that the determinant of direction of differentiation was associated with Notch signaling pathway.  相似文献   
14.
The atypical cells of CD30(+) cutaneous lymphoproliferative disorders (CD30CLD) are commonly of T-cell origin and frequently have a similar morphology as Hodgkin or Reed-Sternberg cells of Hodgkin's lymphoma (HL). HL is one of the tumors associated with CD30CLD. Although most studies support a B-cell derivation of the tumor cells in HL, recently a few cases of classical HL with T-cell genotype have been reported. We report a patient who presented with CD30CLD whose lymph nodes showed classical HL of mixed cellularity subtype at presentation. By single-cell PCR, the same clonal gene rearrangements of the T cell receptor-beta gene locus could be assigned to the CD30(+) and CD15(+) cells of both skin and lymph node. In a lymph node biopsy specimen taken in relapse after several courses of chemotherapy, the CD30(+) tumor cells were abundant. The T cell-derived tumor cells displayed aberrant expression of the Pax-5 gene in all specimens. A common clonal origin of both CD30CLD and HL of the lymph node in the patient presented here suggests that HL with T-cell genotype exists in association with CD30CLD as well as in sporadic cases and may share clonal origin with the skin tumor.  相似文献   
15.
Although estrogen is known to play a crucial role in the pathogenesis of breast cancer, the molecular mechanisms underlying the action of estrogen remain elusive. In the present study, we focused on keratinocyte growth factor (KGF) and its receptor (KGFR) in the pathogenesis of breast cancer, as a growth factor mediating estrogen action, since significant roles of KGF were demonstrated in various steroid hormone-dependent tissues. First, using paraffin-embedded specimens from 42 breast cancer patients, we examined expression patterns of KGF and KGFR by both immunohistochemistry using newly generated antibodies and nonradioactive in situ hybridization with T-T dimerized synthetic oligonucleotide probes. We next compared the results with the expression of estrogen receptor (ER) alpha and beta, proliferative activity and apoptotic frequency (TUNEL staining). Also, the similar approaches were taken to analyze the expression and role of KGF in ER-positive (MCF7, ZR-75-1) and ER-negative (SK-BR-3, MDA-MB-231) human breast cancer cell lines in vitro. In the surgical specimens, KGF was expressed in cancer cells as well as stromal cells in 19/42 cases (45%), while KGFR was found in cancer cells in 24/42 cases (57%). The distribution of protein and mRNA in the analysis of both KGF and KGFR expression generally coincided. Moreover, KGF expression was closely associated with the expression of ER alpha, and the coexpression of KGF and KGFR significantly correlated with lower TUNEL index, but not with proliferative activity. In accordance with the in vivo findings, KGF expression was detected only in ER alpha-positive MCF7 and ZR-75-1 cells in vitro. And more importantly, we found the inhibitory effect of KGF upon the induction of apoptosis by anticancer drugs in MCF7 cells. Collectively, our results indicate that ER alpha may be involved in KGF expression, and that KGF may play antiapoptotic roles, rather than mitogenic, in human breast cancer.  相似文献   
16.
Stromal cells in the lamina propria of the human oviduct mucosa are unique cells that can differentiate into decidual cells during ectopic pregnancy in the oviduct. The nature of stromal cells is still unknown. In the present study, we investigated human oviductal stromal cells with transmission electron microscopy and immunohistochemistry and revealed that they had ultrastructural features similar to myofibroblasts and expressed alpha-smooth muscle actin, a marker used to identify myofibroblasts. Primary cilia were also one of the characteristic profiles of the stromal cells. These findings showed that the connective tissue-stromal cells in the human oviduct mucosa are myofibroblasts. They are considered to play an important role in the transport of oocytes by bringing about contraction of the mucosal folds.  相似文献   
17.
Chlorella vulgaris, an unicellular green algae, or its acetone-extract (Ac-Ex) were administered orally to Meth A tumor bearing BALB/c or (BALB/c DBA/2)F1 (CDF1) mice. When CDF1 mice were fed daily with 10% dried powder of Chlorella vulgaris (CVP) containing diet before and after Meth A tumor inoculation, the growth of rechallenged Meth A tumor was significantly suppressed in an antigen-specific manner. Augmentation of antitumor resistance was exhibited also by Winn assay using lymph node cells of tumor-bearing mice orally administered with CVP or Ac-Ex. Antigen-specific concomitant immunity in these mice were mediated by cytostatic T cells but not by cytotoxic T cells. Natural killer cells seemed not to contribute in antitumor resistance in this system.  相似文献   
18.
Immunohistochemical expression of proliferating cell nuclear antigen (PCNA) was studied in the endometrium and in endometriotic lesions during the menstrual cycle and in post-menopausal patients. During the menstrual cycle, in the basal layer of the endometrium, an increase in the number of positive indices (PI) of PCNA was observed in epithelial cells from the menstrual phase. It reached a maximum in the proliferative phase and decreased in the secretory phase. However, no change was observed in the stromal cells of the basal layer. In the functional layer of the endometrium, the PI of the epithelial cells showed a high peak in the late proliferative phase, decreased sharply in the secretory phase and remained unchanged thereafter. The PI of the stromal cells in the functional layer showed two peaks, one in the late proliferative and the other in the mid and late secretory phase. In the endometriotic lesions, except for the proliferative phase, the number of PI was significantly higher than that of the corresponding endometrium and no significant changes were observed during the menstrual cycle. In post-menopausal endometriotic lesions, the number of PI was also higher than that of the corresponding endometrium. Thus the numbers of PI differed between the endometrium and endometriotic lesions in the same patients. These results imply that the endometriotic lesions are constantly more proliferative than the endometrium irrespective of the hormonal milieu during both the menstrual cycle and in a post-menopausal environment.  相似文献   
19.
A 46-year-old man with chronic myelogenous leukemia was found to have a new complex translocation. In chronic phase, all of the bone marrow cells had a rearrangement of a t(2;9;14;22) (p21;q34;q32;q11). Southern blot analysis of leukocyte DNA revealed rearrangement of the breakpoint cluster region (bcr) within the 5.8-Kb bcr. The patient eventually died in blast crisis 28 months later. The cytogenetic findings of bone marrow cells showed a 46,XY,t(2;9;14;22)(p21;q34;q32;qll),add(lp),del(3q) karyotype in blast crisis.  相似文献   
20.
The inner avascular zone of the meniscus has limited healing capacity as the area is poorly vascularized. Although peptide hydrogels have been reported to regenerate bone and cartilage, their effect on meniscus regeneration remains unknown. We tested whether the self‐assembling peptide hydrogel scaffold KI24RGDS stays in the meniscal lesion and facilitates meniscal repair and regeneration in an induced rabbit meniscal defect model. Full‐thickness (2.0 mm diameter) cylindrical defects were introduced into the inner avascular zones of the anterior portions of the medial menisci of rabbit knees (n = 40). Right knee defects were left empty (control group) while the left knee defects were transplanted with peptide hydrogel (KI24RGDS group). Macroscopic meniscus scores were significantly higher in the KI24RGDS group than in the control group at 2, 4, and 8 weeks after surgery. Histological examinations including quantitative and qualitative scores indicated that compared with the control group, the reparative tissue in the meniscus was significantly enhanced in the KI24RGDS group at 2, 4, 8, and 12 weeks after surgery. Immunohistochemical staining showed that the reparative tissue induced by KI24RGDS at 12 weeks postimplantation was positive for Type I and II collagen. KI24RGDS is highly biocompatible and biodegradable, with strong stiffness, and a three dimensional structure mimicking native extracellular matrix and RGDS sequences that enhance cell adhesion and proliferation. This in vivo study demonstrated that KI24RGDS remained in the meniscal lesion and facilitated the repair and regeneration in a rabbit meniscal defect model.  相似文献   
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