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71.
72.
Keiji Nagai Yukihiko Ueno Nobuo Takamiya Masao Kaneko 《Macromolecular chemistry and physics.》1995,196(4):1241-1250
The photoluminescent Ru(bpy) complex was dispersed in a polysiloxane film containing 2,2′-bipyridine (bpy) pendant groups. The unusually long photoluminescence lifetime of the Ru(bpy) (1,94 μs at 25°C) and the blue-shifted photoluminescent wavelength suggest a rigid polymer matrix. The fluorescence yield becomes lower with higher probe concentration, indicating concentration quenching. According to the analysis based on Stern-Volmer plots, the quenching obeys a mechanism composed of both static and dynamic processes. A statistical intermolecular distance distribution between the probes was used to interpret the results in terms of static and dynamic quenching. It is shown that in the present system the dispersed complexes diffuse slightly during the excited state. 相似文献
73.
Takahashi K Nakayama Y Horiuchi H Ohta T Komoriya K Ohmori H Kamimura T 《Immunopharmacology and immunotoxicology》2002,24(3):335-347
1Alpha,25-Dihydroxyvitamin D3 (1,25(OH)2D3) has been shown to modulate the production of various cytokines or the expression of certain differentiation markers in human T cells or monocytes. Its effects on neutrophils, however, are poorly understood. In this paper, we show several lines of evidence indicating that neutrophils express functional vitamin D receptors (VDR). Sort-purified neutrophils from human peripheral blood expressed VDR mRNA at a level comparable to that of monocytes. As reported to occur in monocytes, protein expression of CD14 on the cell surface of neutrophils was augmented when the cells were incubated with 1,25(OH)2D3. To investigate the physiological roles for VDR in neutrophils, we investigated possible modulating effects of 1,25(OH)2D3 on the expression of several genes in lipopolysaccharide-stimulated neutrophils by using differential display analysis. Of the genes we identified, trappin-2/elafin/SKALP, which was originally reported to be an inhibitor of elastase, was induced in neutrophils by lipopolysaccharide, but was suppressed significantly in the presence of 1,25(OH)2D3. Under the same conditions, interleukin-1beta expression was also inhibited. These findings suggest that 1,25(OH)2D3 has a potential to affect the inflammatory process by modulating the expression of neutrophil genes. 相似文献
74.
Nakamichi I Takakuwa T Tanio Y Iuchi K Aozasa K 《Virchows Archiv : an international journal of pathology》2005,447(5):888-891
Pyothorax-associated lymphoma (PAL) is a B-cell lymphoma which develops in the pleural cavity of patients with an over-20-year
history of pyothorax. Aberrant expression of surface antigens is occassional in PAL, although genotype is not fully investigated.
We report here a PAL with dual genotype, i.e., simultaneous immunoglobin (Ig) and T-cell receptor (TcR) gene rearrangement.
An 82-year-old woman with pain on the left side of the chest was admitted. She had been suffering from pyothorax after artificial
pneumothorax for treatment of tuberculosis of the pulmonary when she was 18 years old. The mass that was confined to the left
pleural cavity affected by pyothorax was biopsied and histologically diagnosed as diffuse large cell lymphoma. The tumor cells
were positive for CD20, CD16, and TIA-1 but negative for CD79a, CD45RO, CD43, CD3, and CD56. Surface antigen expression was
further investigated in cultured cells, showing that the cultured cells did not express representative B-cell markers, except
for CD20, as well as T-cell markers, but were positive for CD16, CD30, and CD103. Southern blotting revealed the monoclonally
rearranged bands of both Ig heavy chain and TcR gene. The patients died of tumors 14 months after admission. Aberrant genotype
and immunophenotype of PAL cells is discussed in reviewing the pertinent literature. 相似文献
75.
Katsuaki Ukai Kazuo Terashima Yutaka Imai Haruhide Shinzawa Yoshimi Okuyama Tsuneo Takahashi Makoto Ishikawa 《Pathology international》1990,40(9):623-634
In an effort to settle the conflicting views on the proliferation kinetics of Kupffer cells (Kc), we performed 2/3 partial hepatectomy on rats injected with Pelikan ink. Using an anti-rat macrophage monoclonal antibody, ED 2, we evaluated the numerical changes in total, carbon-positive ED 2+ cells and carbon-negative ED 2+ cells in the portal and central area. We also analyzed the ultrastructure and peroxidase cytochemistry of various types of cells observed during regeneration. The total numbers of ED 2+ cells in the remaining liver increased rapidly from day 2 to 5, and the number of dividing ED 2+ cells reached a maximum on day 2. Thus, the numerical increase in ED 2+ cells corresponded to the division phase. In contrast, the carbon-labeling experiment showed a continuous increase of carbon negative ED 2+ cells from day 2 to 7. In the central area where division was less frequent, the proportion of carbon-positive cells decreased markedly to 50% on day 7, as against 97% in control rats. These findings suggest the possibility of an influx of carbon-negative Kc in addition to cell division. Ultrastructurally, the presence of carbon-negative "small Kc" and "immature Kc" with morphological features different from those of carbon-positive Kc was demonstrated. Such carbon-negative Kc with a high nucleus-to-cytoplasm ratio and rather few phagosomes, were not observed in control rats. Furthermore, we demonstrated two types of possible precursor cell, i.e. "transitional" forms between monocytes and Kc, and "immature macrophages". The former showed peroxidase activity in some lysosomes as well as in the rough endoplasmic reticulum and nuclear envelope. Our result indicated that the proliferation kinetics of Kc depend upon both local proliferation and influx. 相似文献
76.
Interaction between fibroblast cells and fluorinated polyimide with nano-modified surface 总被引:2,自引:0,他引:2
Nagaoka S Ashiba K Okuyama Y Kawakami H 《The International journal of artificial organs》2003,26(4):339-345
In this study, we investigated the effect of surface nano-modification of aromatic fluorinated polyimide (6FDA-6FAP) derived from 2,2'-bis (3,4-dicarboxyphenyl) hexafluoropropane dianhydride (6FDA) and 2,2'-bis (4-aminophenyl) hexafluoropropane (6FAP) on the interaction with proteins and cells. The surface of 6FDA-6FAP was modified by surface-rubbing showed nano-ordered stripes along the rubbing direction. The rat fibroblast FR cells formed multicellular spheroids with high cell density on the rubbed surface then expressed excellent collagen production similarly in vivo, while on the non-modified surface the cells formed two-dimensional monolayers and the collagen production was negligible. The modulation of cell function by the surface nano-modification along with surface micro-modification may be one of the most important considerations during the design and manufacture of novel biochips or tissue engineering materials. 相似文献
77.
Shigeru Okuyama Hiroko Shimamura Sanae Hashimoto Hironaka Aihara 《Naunyn-Schmiedeberg's archives of pharmacology》1987,335(6):667-672
Summary Subcutaneously (s.c.) administered apomorphine (0.0125–0.4 mg/kg) or physostigmine (0.025–0.4 mg/kg) to rats elicited yawning. The dose-response curves were bellshaped. The peak effects of apomorphine and physostigmine were observed with a dose of 0.1 mg/kg of each drug. Yawning elicited by apomorphine (0.1 mg/kg) or physostigmine (0.1 mg/kg) was reduced by intraperitoneally (i.p.) administered 5-hydroxytryptophan (5-HTP, 50–200 mg/kg, given 30 min before). Yawning elicited by apomorphine but not by physostigmine was enhanced by p-chlorophenylalanine (p-CPA, 25–400 mg/kg i.p., given 24 h before). Apomorphine elicited but not physostigmine-elicited yawning was enhanced by pretreatment with 5,7-dihydroxytryptamine (5,7-DHT, 8 g/rat, given 14 days before into the dorsal raphe). This treatment led to a 35% depletion of serotonin (5-HT) in the striatum. 5-HTP, p-CPA or 5,7-DHT given alone did not elicit yawning. Bilateral, intrastriatal microinjection of apomorphine (1.5 –50 g/site) but not physostigmine (5–50 g/site) elicited yawning. The dose-response curve was also bell-shaped. These results indicate that central serotonergic pathways play an important role in modulating drug-elicited yawning in rats.
Send offprint requests to S. Okuyama at the above address 相似文献
78.
Decuroside V [3' ( R)-hydroxy-nodakenin-3'-ol] and decuroside IV [nodakenetin 4'- O-beta- D-apiofuranosyl (1-->6)beta-D-glucopyranolsyl], two new coumarin glycosides, were isolated from a Chinese drug sold under the name of Si-Qian-Hu (Seizenko) and Kwan-Si Qian-Hu (Koseizenko), the roots of PEUCEDANUM DECURSIVUM Maxim. (Umbelliferae). The structures were determined by means of spectroscopic analysis and chemical reactions. (1)H-NMR spectra showed the beta-configuration of the all sugar linkages. 相似文献
79.
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