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991.
992.
BACKGROUND: The crescent-forming mechanism has not yet been fully clarified and a cell which constitutes a crescent still remains controversial. This study was undertaken to analyze the crescent-forming mechanism in an irreversible Thy-1 model by applying a new marker-recognizing monoclonal antibody (mAb) OS-3. METHODS: An irreversible Thy-1 model was induced by an intravenous injection of 500 microg of anti-Thy-1 mAb 1-22-3 to unilaterally nephrectomized Wistar rats. Seven rats were sacrificed 3, 7 and 14 days after the mAb injection respectively and the renal tissues were examined histologically and immunohistochemically. RESULTS: Inflammatory cells were demonstrated mostly in the interstitium, but they were located within advanced cellular crescents in later stages. OS-3, which stained parietal glomerular epithelial cell (PGEC) only partly in a normal rat kidney section, reacted to PGEC more extensively at day 3 and also with cellular crescents at day 7. During the course of this model the podocytes lost their characteristic to be stained by anti-podocalyxcin Ab and obtained a new marker of a diseased state, i.e. to be positively stained by OS-3. CONCLUSION: Glomerular epithelial cells, but not inflammatory cells, are suggested to directly participate in the crescent formation in early stages, and podocytes with phenotypic changes might be partly involved in the formation of the crescents. 相似文献
993.
Electroretinogram analysis of relative spectral sensitivity in genetically identified dichromatic macaques
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Akitoshi Hanazawa Akichika Mikami Puti Sulistyo Angelika Osamu Takenaka Shunji Goto Akishi Onishi Satoshi Koike Tetsuo Yamamori Keichiro Kato Aya Kondo Bambang Suryobroto Achmad Farajallah Hidehiko Komatsu 《Proceedings of the National Academy of Sciences of the United States of America》2001,98(14):8124-8127
The retinas of macaque monkeys usually contain three types of photopigment, providing them with trichromatic color vision homologous to that of humans. However, we recently used molecular genetic analysis to identify several macaques with a dichromatic genotype. The affected X chromosome of these animals contains a hybrid gene of long-wavelength-sensitive (L) and middle-wavelength-sensitive (M) photopigments instead of separate genes encoding L and M photopigments. The product of the hybrid gene exhibits a spectral sensitivity close to that of M photopigment; consequently, male monkeys carrying the hybrid gene are genetic protanopes, effectively lacking L photopigment. In the present study, we assessed retinal expression of L photopigment in monkeys carrying the hybrid gene. The relative sensitivities to middle-wavelength (green) and long-wavelength (red) light were measured by electroretinogram flicker photometry. We found the sensitivity to red light to be extremely low in protanopic male monkeys compared with monkeys with the normal genotype. In female heterozygotes, sensitivity to red light was intermediate between the genetic protanopes and normal monkeys. Decreased sensitivity to long wavelengths was thus consistent with genetic loss of L photopigment. 相似文献
994.
A case of dermatomyositis complicated with pneumomediastinum that was successfully treated with cyclosporin A] 总被引:3,自引:0,他引:3
We reported the case of a 39-year-old man with dermatomyositis (DM) complicated with subcutaneous emphysema and pneumomediastinum during steroid therapy. The patient had complained of muscle weakness, dyspnea and skin eruption on his anterior chest wall 6 months prior to admission. He was diagnosed as having DM on the basis of an elevation in myogenic enzymes, myogenic changes in electromyography, a skin biopsy and a muscle biopsy. Chest roentgenogram revealed interstitial pneumonia (IP) in the lower lobes of the lungs. The administration of prednisolone (60 mg/day) was initiated, which resulted in improvement of DM. Fifteen days after the initiation of the steroid therapy, the patient developed subcutaneous emphysema and pneumomediastinum. Additional administration of cyclosporin A (CsA) enabled us to rapidly taper the dose of prednisolone without aggravating the diseases. Several reports have shown that vasculitis might be involved in the pathogenesis of pneumomediastinum in DM patients. Infection and tissue fragility due to steroid therapy worsen the outcome of those patients. CsA therapy may improve the outcome through the anti-vasculitic- and steroid sparing-effects. 相似文献
995.
J. Susuki M. Nawata M. Koike R. Wada I. Sekigawa N. Iida H. Hashimoto 《Modern rheumatology / the Japan Rheumatism Association》2001,11(4):336-339
We report two cases of bone marrow hemophagocytosis. One patient had adult-onset Still's disease, and the other had herpes
zoster associated with potential autoimmune abnormalities. Our findings suggested a pos-sible role of cytokines and/or antibodies
in the induction of hemophagocytosis in patients with connective tissue diseases and/or immune abnormalities.
Received: November 28, 2000 / Accepted: March 12, 2001 相似文献
996.
Two types of mast cells, MC(T) and MC(TC), exist in humans. MC(T) and MC(TC) are different in their granular neutral proteases, tissue localizations, and functions. This article describes the differences between the cutaneous mast cell receptors. 相似文献
997.
Satoshi Yokosawa Tomoyuki Koike Yasushi Kitagawa Waku Hatta Kaname Uno Yasuhiko Abe Katsunori Iijima Akira Imatani Shuichi Ohara Tooru Shimosegawa 《World journal of gastroenterology : WJG》2009,15(35):4402-4409
AIM: To assess each layer of the optical coherence tomography (OCT) image of the esophageal wall with reference to the histological structure, METHODS: Resected specimens of fresh pig esophagus was used as a model for the esophageal wall. We injected cyanoacrylate adhesive into the specimens to create a marker, and scanned them using a miniature OCT probe. The localization of these markers was assessed in the OCT images. Then we compared the OCT-imaged morphology with the corresponding histological section, guided by the cyanoacrylate adhesive markers. We prepared a second set of experiments using nylon sutures as markers. RESULTS: The OCT image of the esophageal specimen has a clear five-layered morphology. First, it consisted of a relatively less reflective layer; second, a more reflective layer; third, a less reflective layer; fourth, a more reflective layer; and fifth, a less reflective layer. Comparing the OCT images with marked histological sections showed that the first layer corresponded to stratified squamous epithelium; the second to lamina propria; the third to muscularis mucosa; fourth, submucosa; and fifth, muscularis propria with deeper structures of the esophageal wa CONCLUSION: We demonstrated that the OCT image of the normal esophageal wall showed a five- layered morphology, which corresponds to histological esophageal wall components. 相似文献
998.
Yasumasa Nishimura Michihide Mitsumori Masahiro Hiraoka Ryuta Koike Kiyoshi Nakamatsu Masashi Kawamura Yoshiharu Negoro Kazuhisa Fujiwara Hideyuki Sakurai Norio Mitsuhashi 《Radiotherapy and oncology》2009,92(2):260-265
Purpose
A randomized phase II study was conducted to compare the toxicity and efficacy of combining short-term chemotherapy (CT) or protracted CT with radiotherapy (RT) for esophageal cancer.Materials and methods
Eligible patients were <75 years and with performance status (PS) of 0-2, and had stages II-IVA esophageal cancer. Two cycles of cisplatin 70 mg/m2 for 1 day and 5FU 700 mg/m2 for 5 days (arm A) or cisplatin 7 mg/m2 for 10 days and 5FU 250 mg/m2 for 14 days (arm B) were given with RT of 60 Gy/30 fractions/7 weeks (1-week split).Results
Of 91 patients enrolled, 46 were randomized to arm A and 45 to arm B. Two cycles of CT were given concurrently with RT for 89% in arm A and for 71% in arm B with significant difference (P = .031). The 2- and 5-year overall survival rates for arm A were 46% and 35%, while those for arm B were 44% and 24%, respectively, without significant difference. The 2- and 5-year progression-free survival rates for arm A were 30% and 30%, while those for arm B were 29% and 12%, respectively.Conclusions
Protracted infusion CT with RT provides no advantage over standard short-term infusion CT with RT for esophageal cancer. 相似文献999.
Patricia Bortman Rozenchan Dirce Maria Carraro Helena Brentani Louise Danielle de Carvalho Mota Elen Pereira Bastos Elisa Napolitano e Ferreira Cesar H. Torres Maria Lúcia Hirata Katayama Rosimeire Aparecida Roela Eduardo C. Lyra Fernando Augusto Soares Maria Aparecida Azevedo Koike Folgueira João Carlos Guedes Sampaio Góes Maria Mitzi Brentani 《International journal of cancer. Journal international du cancer》2009,125(12):2767-2777
The importance of epithelial‐stroma interaction in normal breast development and tumor progression has been recognized. To identify genes that were regulated by these reciprocal interactions, we cocultured a nonmalignant (MCF10A) and a breast cancer derived (MDA‐MB231) basal cell lines, with fibroblasts isolated from breast benign‐disease adjacent tissues (NAF) or with carcinoma‐associated fibroblasts (CAF), in a transwell system. Gene expression profiles of each coculture pair were compared with the correspondent monocultures, using a customized microarray. Contrariwise to large alterations in epithelial cells genomic profiles, fibroblasts were less affected. In MDA‐MB231 highly represented genes downregulated by CAF derived factors coded for proteins important for the specificity of vectorial transport between ER and golgi, possibly affecting cell polarity whereas the response of MCF10A comprised an induction of genes coding for stress responsive proteins, representing a prosurvival effect. While NAF downregulated genes encoding proteins associated to glycolipid and fatty acid biosynthesis in MDA‐MB231, potentially affecting membrane biogenesis, in MCF10A, genes critical for growth control and adhesion were altered. NAFs responded to coculture with MDA‐MB231 by a decrease in the expression of genes induced by TGFβ1 and associated to motility. However, there was little change in NAFs gene expression profile influenced by MCF10A. CAFs responded to the presence of both epithelial cells inducing genes implicated in cell proliferation. Our data indicate that interactions between breast fibroblasts and basal epithelial cells resulted in alterations in the genomic profiles of both cell types which may help to clarify some aspects of this heterotypic signaling. © 2009 UICC 相似文献
1000.
Nishimura T Andoh A Inatomi O Shioya M Yagi Y Tsujikawa T Fujiyama Y 《Oncology reports》2008,19(1):105-110
Amphiregulin and epiregulin belong to the epidermal growth factor family and mediate the biological functions of epithelial and mesenchymal cells through epidermal growth factor receptors. In this study, we evaluated the amphiregulin and epiregulin expression in neoplastic and inflammatory lesions from the human colon. Surgically-obtained specimens were stained using standard immunohistochemical procedures. Amphiregulin and epiregulin were not expressed in the normal colonic mucosa, but were clearly detectable in adenomas and carcinomas. Weak immunostaining was also detected in mesenchymal cells from the tumor tissues. In the active mucosa of patients with ulcerative colitis and Crohn's disease, amphiregulin was mainly expressed by the epithelial cells. In addition, positive immunostaining was also detectable in the surrounding mesenchymal cells. In conclusion, amphiregulin and epiregulin may play important roles in colonic tumor growth and mucosal repair in the inflamed mucosa of inflammatory bowel disease. 相似文献