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Evidence of the monoclonal composition of human endometrial epithelial glands and mosaic pattern of clonal distribution in luminal epithelium 总被引:8,自引:0,他引:8 下载免费PDF全文
Tanaka M Kyo S Kanaya T Yatabe N Nakamura M Maida Y Okabe M Inoue M 《The American journal of pathology》2003,163(1):295-301
The endometrium is a highly regenerative tissue that plays a crucial role in implantation. We examined the clonal constitution of glandular cells as well as the luminal epithelium of this unique tissue. Using collagenase-based digestion techniques with microscopic manipulation, we isolated individual human endometrial glands and examined their clonality using a polymerase chain reaction-based assay for nonrandom X chromosome inactivation with an X-linked androgen receptor gene. Most of the glands analyzed were composed of monoclonal populations of epithelial cells and one of the glands exhibited a loss of heterogeneity in the androgen receptor gene. In addition, adjacent glands within a 1-mm(2) area shared clonality, suggesting that clonality of the luminal epithelium is regionally defined. The clonality of endometrium was further confirmed in a study of female mice that harbor the green fluorescent protein gene on either the maternal or paternal X chromosome. Fluorescent microscopy of uterine sections revealed that individual endometrial glands consisted completely of either fluorescent or nonfluorescent cells and that the surface epithelium exhibited a clear boundary between these cell types. These findings suggest that single or multiple stem cells with uniform clonality exist on the bottom of each endometrial gland and genetic alterations occurring in such cells may play a critical role in endometrial carcinogenesis. The possible association between area-specific X inactivation of the endometrial surface and the endometrial receptivity of embryo implantation remains to be clarified. 相似文献
84.
Hitoshi Nishimura Masashi Emoto Kenji Hiromatsu Shunsuke Yamamoto Keiko Matsuura Hiroshi Gomi Toshio Ikeda Shigeyoshi Itohara Yasunobu Yoshikai 《European journal of immunology》1995,25(5):1465-1468
The secretion of tumor necrosis factor (TNF)-α from macrophages is regulated by both priming and triggering signals. We found that macrophages from mice lacking γδ T cells [T cell receptor (TCR) δ?/- mice], which lack the gene encoding the δ chain, produced only small amounts of TNF-α in response to lipopolysaccharide (LPS) and showed a reduced level of expression of CD14. Pre-incubation of macrophages from TCR δ-/- mice with γδ T cells from their TCR δ+/- littermates restored their capacity to produce TNF-α in response to LPS. The priming activity of γδ T cells was in part inhibited by neutralizing anti-interferon (IFN)-γ monoclonal antibodies. Collectively, these results suggest that γδ T cells play a role in priming macrophages to a steady state of activation via IFN-γ secretion, which allows them to produce TNF-α when exposed to LPS. 相似文献
85.
Maki Yoshikawa Masashi Hosokawa Kazuo Miyashita Hoyoku Nishino Takeshi Hashimoto 《Nutrients》2021,13(4)
Fucoxanthin (Fx) has preventive effect against muscle atrophy and myotube loss in vitro, but it has not yet been examined in vivo. Therefore, we aimed to investigate the effect of Fx on dexamethasone (Dex)-induced muscle atrophy and fat mass in mice. ICR mice were fed with Fx diets from 2 weeks before Dex treatment to the end of the study. Muscle atrophy was induced in the mice by oral administration of Dex. Body weight was significantly lower by Dex treatment. Visceral fat mass in the Fx-treated group were significantly lower than those in the control group. The Dex-induced decrease in tibialis anterior muscle mass was ameliorated by Fx treatment. Fx treatment significantly attenuated muscle lipid peroxidation compared with the control and Dex-treated groups. The phosphorylation of AMPK was significantly higher in the Dex-treated group than in the control group. The expression of cytochrome c oxidase (COX) IV was significantly higher in the Fx-treated group than in the control group. These results suggest that Fx may be a beneficial material to prevent muscle atrophy in vivo, in addition to the effect of fat loss. 相似文献
86.
Nakagawa Ichiro Park HunSoo Kotsugi Masashi Motoyama Yasushi Myochin Kaoru Takeshima Yasuhiro Matsuda Ryosuke Nishimura Fumihiko Yamada Syuichi Takatani Tsunenori Kichikawa Kimihiko Nakase Hiroyuki 《Neurosurgical review》2021,44(3):1493-1501
Neurosurgical Review - The present study aimed to determine the incidence of intraprocedural motor-evoked potential (MEP) changes and to correlate them with intraprocedural ischemic complications... 相似文献
87.
Nobuhiro Okuno Shuhei Otsuki Jo Aoyama Kosuke Nakagawa Tomohiko Murakami Kuniaki Ikeda Yoshinobu Hirose Hitoshi Wakama Tomohiro Okayoshi Yoshinori Okamoto Yoshiaki Hirano Masashi Neo 《Journal of orthopaedic research》2021,39(1):165-176
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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Takuya Sekiguchi Yoshihiro Hagiwara Akira Ando Kenji Kanazawa Kazuaki Suzuki Masashi Koide Yutaka Yabe Satsuki Onoda Eiji Itoi 《Journal of orthopaedic science》2021,26(4):595-598
BackgroundThe Shoulder Pain and Disability Index (SPADI) is a simple disease specific questionnaire that is used to evaluate the impact of shoulder disorders. The purpose of this study was to translate the SPADI into Japanese (SPADI-Jp) and evaluate its reliability and validity in Japanese patients with shoulder disorders.MethodsCross-cultural adaptation of the SPADI was performed according to international guidelines. A total of 100 patients with shoulder disorders participated in this study. Each participant was asked to finish the SPADI-Jp, Disability of Arm, Shoulder and Hand (DASH), and the Short-Form 36 (SF-36) at the initial visit. Thirty-four patients repeated the SPADI-Jp to assess the test–retest reliability. The test–retest reliability was quantified using the interclass correlation coefficient (ICC), while Cronbach's alpha was calculated to assess the internal consistency. The construct validity was assessed using Spearman's rank correlation coefficients.ResultsInternal consistency in the SPADI-Jp was very high (0.969), as measured by the Cronbach's alpha. The ICC of the SPADI-Jp was 0.930. There was a strong, positive correlation between the DASH and the SPADI-Jp (r = 0.837, p < 0.001). The SPADI-Jp was significantly correlated with most of the SF-36 subscales. The correlations of the SPADI-Jp with physical subscales of the SF-36 were stronger than those with the other subscales.ConclusionsWe demonstrated that the SPADI-Jp is a reliable and valid self-assessment tool. Because cross-cultural adaptation, validation, and reliability of the disease-specific questionnaire for shoulder pain and disability have not been evaluated in Japan, the SPADI-Jp can be useful for evaluating such patients in the Japanese population. 相似文献
90.
Michihito Ishizawa Hidetoshi Okabe Keiji Matsumoto Shigeru Morimoto Sinsuke Hukuda Tokuhiro Chano 《Journal of orthopaedic science》2021,26(4):660-665
BackgroundTo better understand the nature of magnetic resonance imaging (MRI) findings in schwannomas, especially in the “target sign” of these findings, the histopathological investigation was performed.MethodsThe MRI findings were correlated with histopathological features in 22 samples of schwannomas, which were mostly resected from the extremities. The histopathological analyses included alcian blue staining and immunohistochemical staining for S-100 protein, proliferating cell nuclear antigen (PCNA) and epithelial membrane antigen (EMA).ResultsSeven of the 22 samples of schwannomas of the extremities exhibited target signs including a peripheral zone of homogeneously high signal intensity and a central zone of heterogeneous signal intensity in T2-weighted images. Gadolinium-enhanced T1–weighted images demonstrated a central heterogeneous enhancement and a peripheral ring of homogeneously low signal intensity. Histopathologically, S-100 and PCNA were positive only in the central heterogeneous signal area. In contrast, EMA was only stained on the degenerative epi/perineurium in the peripheral zone.ConclusionIn schwannomas of the extremities showing target sign in T2-weighted images, histopathologically, the peripheral areas were suggested to be mucinous degeneration of the epineurium or perineurium, while the central areas were composed of truly neoplastic cells. 相似文献