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51.
Yasuhiko Hirata Hiromi Ishibashi Harumichi Kimura Kazuhiro Hayashida Masanori Nagano Hideo Okubo 《Inflammation》1985,9(2):201-209
Isolated rat Kupffer cells produced a factor which stimulated the synthesis of
2-macroglobulin (2M) in primary cultured rat hepatocytes. Although Kupffer cells placed in culture produced the factor without stimulation by lipopolysaccharide (LPS), the LPS-stimulated cells produced larger amounts of the factor. On the other hand, the production of the factor was inhibited by addition of actinomycin D. The induction of2M synthesis by cultured hepatocytes was enhanced in the presence of dexamethasone (Dex), in that hepatic synthesis of2M increased by addition of the factor alone and with Dex 1.5 and three- to four-fold, respectively. The factor was nondialyzable and stable at 60°C for 30 min. When the factor was fractionated using the molecular sieve method, the activity recovered in the fraction had a molecular weight of over 30,000. 相似文献
52.
53.
伴有肌样/肌纤维母细胞性分化的隆突性皮纤维肉瘤的临床病理分析 总被引:5,自引:0,他引:5
目的 探讨隆突性皮纤维肉瘤(DFSP)中肌样/肌纤维母细胞性分化的本质及其临床病理学意义。方法 采用常规HE切片对124例DFSP进行筛选,对6例伴有肌样/肌纤维母细胞性分化的DFSP病例进行免疫组织化学标记,其中2例加做电镜检测。结果 肌样/肌纤维母细胞性分化多出现在纤维肉瘤型DFSP(FS-DFSP)中,表现为肿瘤周边部或肿瘤内散在性分布的深嗜伊红色小结节或短要束,由梭形细胞组成,细胞多无异型性,核分裂象也罕见,形态上似平滑肌细胞或肌纤维母细胞。免疫组织化学标记显示肌样区域细胞表达α-平滑肌肌动蛋白和肌物质特异性肌动抗原,不表达CD34;电镜观察证实细胞含有质膜下微丝束、局灶性致密体及微胸饮囊泡样结构,与肌纤维母细胞相一致,结论 DFSP中的肌样/肌纤维母细胞性分化可能是间质中肌纤维母细胞增生的结果,并非代表了瘤细胞的真性肌纤维母细胞性分化。 相似文献
54.
Kusumi T Nishikawa S Tanaka M Ogawa T Jin H Sato F Toh S Hasegawa T Kijima H 《Pathology international》2005,55(12):802-806
Low-grade fibromyxoid sarcoma (LGFMS) is a rare tumor. Reported herein is a case of LGFMS arising in the big toe. The patient was a 58-year-old man who underwent excision of the tumor. The tumor was well-demarcated. Histologically, there were proliferating spindle-shaped tumor cells arranged in a whorled growth pattern, and the stroma showed hyalinized collagen bundles and a myxoid matrix. Nuclear mitotic figures were conspicuous in part. A large rosette-like structure with hyalinized stroma was found, which is characteristic of LGFMS. The differential diagnosis included tumor occurrence in adults; tending to arise in distal extremities; and having bland fibromyxoid histological features, such as fibroma of tendon sheath, low-grade myxofibrosarcoma and acral myxoinflammatory fibroblastic sarcoma. It was not possible to detect the FUS/CREB3L2 and FUS/CREB3L1 fusion genes from the formalin-fixed and paraffin-embedded tissue, although the histological features of the present case were typical of LGFMS. LGFMS may become more common with time, and unique cases may accumulate. 相似文献
55.
Angiogenic endothelium-specific nestin expression is enhanced by the first intron of the nestin gene 总被引:5,自引:0,他引:5
Aihara M Sugawara K Torii S Hosaka M Kurihara H Saito N Takeuchi T 《Laboratory investigation; a journal of technical methods and pathology》2004,84(12):1581-1592
Nestin is a member of intermediate filaments abundantly expressed in neural stem cells and glioblastomas. The nestin gene has four exons and three introns, and neural cell-specific expression is regulated by the second intron. We previously reported that nestin was invariably detected in the tumor endothelium in gliomas even though tumor cells were negative for nestin. In the present study, we further confirmed nestin immunostaining in tumor endothelium of a variety of common cancers, including lung, stomach, colon, and cervical carcinomas. We examined an endothelium-specific regulator using human umbilical vein endothelial cells (HUVECs) and human glioblastoma-derived U251 cells. In a luciferase reporter assay, the first intron plus 5' upstream promoter (5'UP) gave the highest activity, followed by 5'UP, and the second intron plus 5'UP. However, the assay values were much lower by HUVEC extracts than by U251 cell extracts. Although green fluorescent protein expression was positive over all U251 cells under either the first intron, second intron, or ubiquitously active CAG promoter, the fluorescence in HUVECs was limited to a few cells even under the first intron. This difference came from the growth feature of HUVECs which exhibit growth arrest by contact inhibition. We found that the nestin expression was specific to proliferative endothelium, by using proliferation markers in hemangioblastomas and in situ hybridization. Using an endothelial tube formation assay, tyrosine kinase domain-deleted VEGF receptor KDR effectively abolished the tube formation under the first intron. We suggest that the nestin expression in tumor endothelium is enhanced by the first intron. 相似文献
56.
Kida T Nishihira Y Hatta A Wasaka T Nakata H Sakamoto M Nakajima T 《European journal of applied physiology》2003,89(3-4):326-330
We investigated the relationship between somatosensory event-related potentials (ERP) and the variation of reaction time (RT).
For this purpose, we recorded the ERPs (N250 and P300) in fast- and slow-reaction trials during a somatosensory discrimination
task. Strong, standard, and weak target electrical stimuli were randomly delivered to the left median nerve at the wrist with
a random interstimulus interval (900–1,100 ms). All the subjects were instructed to respond by pressing a button with their
right thumb as fast as possible whenever a target stimulus was presented. We divided all the trials into fast- and slow-RT
trials and averaged the data. N250 latency tended to be delayed when the RT was slow, but not significantly. P300 latency
was delayed significantly when the RT was slow, but to a much lesser extent than the RT delay, so we concluded that the change
of RT was not fully determined by the processes reflected by the somatosensory N250 or P300. Furthermore, the larger and earlier
P300 in the fast-RT trials implied that when larger amounts of attentional resources were allocated to a given task, the speed
of stimulus evaluation somewhat increased and RT was shortened to a great extent. N250 amplitude did not significantly vary
in the two RT clusters. In conclusion, the somatosensory N250 reflects active target detection, which is relatively independent
of the modulation of the response speed, whereas the somatosensory P300 could change without manipulation of either the stimulus
or the response processing demand.
Electronic Publication 相似文献
57.
Identification and characterization of intestinal Peyer's patch interferon-alpha producing (plasmacytoid) dendritic cells 总被引:4,自引:0,他引:4
Recently, a subset of murine dendritic cells (DC) has been identified that resembles human plasmacytoid (pDC) the principal interferon-alpha (IFN-alpha) producing cells in blood. In this study, C57BL/10 (B10;H2b) mice were treated with fms-like tyrosine 3 kinase Ligand (Flt3L; 10 microg/d; i.p.; 10 days) that expands DC selectively in vivo. Putative pDC (CD11c+B220+) were identified in the subepithelial dome and in interfollicular regions of intestinal Peyer's patches (PP) from both normal and Flt3L-treated animals. Freshly-isolated, immunobead-purified CD11c+ DC from PP were flow-sorted to obtain lineage- (CD11b-CD19-) CD11c+ B220+ DC (purity>96%). Flow cytometric analysis revealed that these sorted PPpDC were negative for surface markers associated with myeloid DC (CD11b) and expressed only low levels of the "lymphoid-related" DC marker CD8alphaalpha+. They expressed low levels of costimulatory molecules and moderate MHC class II. They proved weak stimulators of na?ve allogeneic (C3H; H2k) T-cell proliferation. Cytospin preparations of sorted CD11c+B220+ cells revealed plasmacytoid morphology similar to that of human pDC. Immunocytochemistry and enzyme immunoassay revealed that, within 24-hour culture with Herpes simplex virus (10 p.f.u./cell), a subpopulation of stimulated (but not unstimulated) CD11c+B220+ DC produced and secreted IFN-alpha. This novel DC subset may play important roles in innate and adaptive immune responses of the gut and in the regulation of mucosal immune reactions. 相似文献
58.
59.
60.
Masayuki Ishihara PhD Kiyohaya Obara MD Singo Nakamura PhD Masanori Fujita MD PhD Kazunori Masuoka MD Yasuhiro Kanatani MD PhD Bonpei Takase MD PhD Hidemi Hattori PhD Yuji Morimoto MD PhD Miya Ishihara PhD Tadaaki Maehara MD PhD Makoto Kikuchi PhD 《Journal of artificial organs》2006,9(1):8-16
An aqueous solution of photocrosslinkable chitosan containing azide groups and lactose moieties (Az-CH-LA) incorporating paclitaxel
formed an insoluble hydrogel within 30 s of ultraviolet light (UV) irradiation. The chitosan hydrogel showed strong potential
for use as a new tissue adhesive in surgical applications and wound dressing. The fibroblast growth factor (FGF)-2 molecules
retained in the chitosan hydrogel and in an injectable chitosan/IO4-heparin hydrogel remain biologically active, and were gradually released from the hydrogels as they biodegraded in vivo.
The controlled release of biologically active FGF-2 molecules from the hydrogels caused induction of angiogenesis and collateral
circulation occurred in healing-impaired diabetic (db/db) mice and in the ischemic limbs of rats. Paclitaxel, which is an antitumor reagent, was also retained in the chitosan hydrogel
and remained biologically active as it was released on degradation of the hydrogel in vivo. The chitosan hydrogels incorporating
paclitaxel effectively inhibited tumor growth and angiogenesis in mice. The purpose of this review is to describe the effectiveness
of chitosan hydrogel as a local drug delivery carrier for agents (e.g., FGF-2 and paclitaxel) to control angiogenesis. It
is thus proposed that chitosan hydrogel may be a promising new local carrier for drugs such as FGF-2 and paclitaxel to control
vascularization. 相似文献