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991.
Receptor binding activity and cytosolic free calcium response by synthetic endothelin analogs in cultured rat vascular smooth muscle cells 总被引:4,自引:0,他引:4
Y Hirata H Yoshimi T Emori M Shichiri F Marumo T X Watanabe S Kumagaye K Nakajima T Kimura S Sakakibara 《Biochemical and biophysical research communications》1989,160(1):228-234
Using a variety of synthetic analogs of porcine endothelin (pET), we have studied the effects of these analogs on receptor binding activity and cytosolic free Ca2+ concentrations ([Ca2+]i) in cultured rat vascular smooth muscle cells (VSMC). Removal of C-terminal Trp21 residue, truncated derivatives pET(1-15) and (16-21), substitution of disulfide bond, Cys(3-11) or Cys(1-15), by Cys (Acm), all resulted in a complete loss of receptor binding activity and [Ca2+]i response, while N-terminal elongation of Lys-Arg residues, but not oxidation of Met7 residue, decreased receptor binding activity and [Ca2+]i response. [Cys1-15,Cys3-11]pET was far more potent than [Cys1-11,Cys3-15]pET in receptor binding and [Ca2+]i response. These data indicate that the C-terminal Trp21 as well as the proper double cyclic structure formed by the intramolecular disulfide bonds of the pET molecule are essential for receptor binding and subsequent [Ca2+]i increase in rat VSMC. 相似文献
992.
Toshihiro Fujimoto Kazuhiko Omote Masayoshi Mai Shunnosuke Natsuume-Sakai 《Biotherapy》1992,5(2):153-163
Peripheral blood lymphocytes (PBL) of gastric cancer patients in advanced stages showed lymphokine activated killer (LAK) activities comparable to those of healthy donors, suggesting potential applicability of LAK cells induced from PBL stimulated with recombinant interleukin-2 (rIL-2) in adoptive immunotherapy (AIT) for gastric cancer. In order to generate a large number of LAK cells from PBL, lymphocytes were cultured with both rIL-2 and phytohemagglutinin (PHA). In this culture, the numbers of cells increased to a greater extent than those in culture with rIL-2 alone but cytotoxic activity did not augment, thus suggesting that this procedure would not afford sufficient clinical effects. On the other hand, a large number of LAK cells with high anti-tumor activities were efficiently induced from spleen cells of the patients by culture of rIL-2; hence clinical usefulness of these LAK cells is anticipated. In regional lymph node lymphocytes (RLNL) cultured with rIL-2, the cytotoxic activities were lower than in those induced in PBL, and a characteristic increase of CD8 + CD11 + suppressor T cells was observed after incubation with rIL-2. Nevertheless, an increase of CD4 + 4B4+ helper inducer T cells was also observed in RLNL after the culture with rIL-2. Furthermore, high cytotoxic activities were induced in RLNL in some cases in which metastasis to the regional lymph nodes was not detected. When gastric cancer patients were pretreated with biological response modifiers (BRM), especially with Lentinan, LAK cells from PBL showed higher NK and LAK activities as compared with those of patients without BRM pretreatment.This work was partly supported by a grant from Hokkoku Cancer Research Foundation. 相似文献
993.
Mitsuro Nakano Toshihiro Hidaka Ryohei Ogura Hiroshi Ueta Masayasu Sugiyama Masanaga Yoshimoto Fumio Yamashita 《Prostaglandins, leukotrienes, and essential fatty acids》1988,31(3):113-116
Washed platelets were prepared from healthy children and adults, and patients with renal glomerular diseases, and incubated with [1-14C] arachidonate to measure the generation capacities of thromboxane (Tx) A2 and 12-hydroxyeicosatetraenoate (12-HETE). Tx generation capacity of platelets was significantly higher in patients with chronic glomerulonephritis, purpura nephritis and lupus nephritis than in healthy control subjects. There was no significant increase in minimal change nephrotic syndrome. 12-HETE showed a decreasing tendency in the glomerular diseases, which was restored to normal level by in vitro addition of indomethacin. Such increased Tx generation capacity of platelets may cause abnormal enhancement of platelet functions and conceivably constitute an aggravating factor of glomerular and microvascular damage in the affected kidney. 相似文献
994.
Haruki Yamada Noboru Kawaguchi Toshihiro Ohmori Yasuyoshi Takeshita Shin-ichi Taneya Toshio Miyazaki 《Carbohydrate research》1984,134(2):275-282
A water- and alkali-insoluble galactosaminoglycan (CON), precipitated with ammonium hydroxide from the culture filtrate of Cordyceps ophioglossoides, is composed mainly of 2-amino-2-deoxy-d-galactose (80.5%) together with small proportions of glucose, galactose, and mannose, protein (3.6%), and acetyl groups (1%). CON was eluted as a single peak in gel filtration, and the average molecular weight was estimated to be ~50,000. Partial, acid hydrolysis of CON gave small CON and homologous 2-amino-2-deoxy-d-galacto-oligosaccharides. Small CON (mol. wt. ~10,000) was soluble in water and composed only of 2-amino-2-deoxy-d-galactose. The results of methylation analysis, 13C-n.m.r. studies, and enzymic hydrolysis indicated small CON to be a (1→4)-linked 2-amino-2-deoxy-α-d-galactopyranan, and the 13C-n.m.r. data indicated the glycosidic linkage in the polygalactosamine moiety of CON to be the same as that of small CON. 相似文献
995.
Hideo Ohkita Miki Namatame Kazuhiro Marumoto Satoru Shimomura Toshihiro Yamanari Shinzaburo Ito 《Liver Transplantation》2016,6(11)
The mechanism of light‐induced degradation in organic solar cells based on regioregular poly(3‐hexylthiophene) and indene‐C60 bisadduct is studied by transient absorption (TA) and electron spin resonance (ESR) measurements. After 45 h light exposure under simulated solar illumination at 100 mW cm?2, the short‐circuit current density, open‐circuit voltage, and fill factor are all degraded by about 20%–30% relative to the initial photovoltaic parameters. For the assignment of limiting conversion processes in the degraded solar cells, exciton diffusion into a donor/acceptor interface, charge transfer at the interface, charge dissociation into free charge carriers, and charge collection to each electrode are observed before and after the light exposure by the TA measurement. As a result, it is found that the charge collection deteriorates after the light exposure because of light‐induced charge trap formation in the bulk of the active layer. The origin of charge traps is further discussed on the basis of ESR measurements and density functional theory calculation. 相似文献
996.
Purpose
To analyze the effects of factors on aqueous humor proinflammatory cytokine and growth factor levels in patients with uveitic glaucoma (UG).Methods
In this cross-sectional study, we enrolled 143 participants: 1) UG patients (n = 39); 2) primary open-angle glaucoma (POAG) patients (n = 36); and 3) cataract surgery patients, as a comparative group (n = 68). Aqueous humor samples were obtained at the start of surgery. Aqueous cytokine levels were determined using a multiplex immunoassay (xMAP and the Human Cytokine/Chemokine Panel I).Results
In UG cases, mean interleukin (IL)-6, IL-8, monocyte chemotactic protein (MCP)-1, tumor necrosis factor (TNF)-α, platelet-derived growth factor (PDGF)-AA, PDGF-AB/BB, and VEGF levels were 171.1, 214.5, 2791.7, 3.5, 23.9, 5.4, and 168.9 pg/mL, respectively, and were higher than those in cataract (non-glaucomatous) cases except PDGF. Levels of IL-6, MCP-1, and VEGF were higher in UG cases than in POAG cases. UG cases with a history of phacoemulsification displayed significantly higher levels of IL-6 (P = 0.0164), IL-8 (P = 0.0003), MCP-1 (P = 0.0465), and PDGF-AB/BB (P = 0.0062) compared to the phakic cases. The presence of cells in the anterior chamber was related to higher levels of IL-8 (P = 0.0002), TNF-α (P = 0.0037), and PDGF-AB/BB (P = 0.0009). The level of PDGF-AB/BB was higher in infectious uveitis than in non-infectious uveitis (P = 0.0211). The level of transforming growth factor (TGF)-β2 was negatively correlated with the levels of MCP-1 (adjusted R2 = 0.28, t = -2.45, P = 0.031) and TNF-α (adjusted R2 = 0.27, t = -2.43, P = 0.032).Conclusion
A history of phacoemulsification, the presence of cells in the anterior chamber, and infectious uveitis were related to aqueous proinflammatory cytokine levels in patients with UG. TGF-β2 might be an anti-inflammatory factor in aqueous humor of UG patients. 相似文献997.
Aya Nawata Hirotsugu Noguchi Yuichi Mazaki Toshihiro Kurahashi Hiroto Izumi Ke-Yong Wang Xin Guo Hidetaka Uramoto Kimitoshi Kohno Hatsumi Taniguchi Yoshiya Tanaka Junichi Fujii Yasuyuki Sasaguri Akihide Tanimoto Toshiyuki Nakayama Sohsuke Yamada 《PloS one》2016,11(4)
BackgroundAccumulating evidence has shown that methionine- and choline-deficient high fat (MCD+HF) diet induces the development of nonalcoholic fatty liver disease (NAFLD), in which elevated reactive oxygen species play a crucial role. We have reported that peroxiredoxin 4 (PRDX4), a unique secretory member of the PRDX antioxidant family, protects against NAFLD progression. However, the detailed mechanism and potential effects on the intestinal function still remain unclear.ConclusionOur present data provide the first evidence of the beneficial effects of PRDX4 on intestinal function in the reduction of the severity of NAFLD, by ameliorating oxidative stress-induced local and systemic injury. We can suggest that both liver and intestine are spared, to some degree, by the antioxidant properties of PRDX4. 相似文献
998.
A new sterol isolated from the seeds of Brassica juncea has been shown to be 24-methylene-25-methylcholesterol. 相似文献
999.
1000.
Microtubules (MTs) are essential for neuronal morphogenesis in the developing brain. The MT cytoskeleton provides physical support to shape the fine structure of neuronal processes. MT-based motors play important roles in nucleokinesis, process formation and retraction. Regulation of MT stability downstream of extracellular cues is proposed to be critical for axonogenesis. Axons and dendrites exhibit different patterns of MT organization, underlying the divergent functions of these processes. Centrosomal positioning has drawn the attention of researchers because it is a major clue to understanding neuronal MT organization. In this review, we focus on how recent advances in live imaging have revealed the dynamics of MT organization and centrosome positioning during neural development. 相似文献