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111.
Tsuji-Yamada J Nakazawa M Takahashi K Iijima K Hattori S Okuda K Minami M Ikezawa Z Sasaki T 《Biochemical and biophysical research communications》2001,280(3):707-712
The tight-skin (Tsk/+) mutant mice, a putative murine model of scleroderma, are characterized by the excessive deposition of collagen and the presence of antinuclear antibodies. Type 2 cytokines, such as IL-4 and IL-6, are capable of regulating the synthesis of various matrix molecules, including type I collagen, by fibroblasts. IL-12 is well known to induce type 1 cytokine production and to reduce type 2 activity. Here, we examined the effect of IL-12 encoding plasmid (pCAGGSIL-12) on the disease progression of Tsk/+ mice. pCAGGSIL-12 plasmid or pCAGGS parental vector was injected intramuscularly 7 times at 3 week intervals into Tsk/+ mice. One week after the last injection, pCAGGSIL-12 administered Tsk/+ mice exhibited a marked decrease in the skin thickness compared with the mice treated with pCAGGS vector. The serum levels of antinuclear antibodies were diminished in pCAGGSIL-12 treated mice. IL-4 production by spleen cells from pCAGGSIL-12 plasmid treated mice was significantly lower than that from vector treated mice. These results indicate that pCAGGSIL-12 administration into Tsk/+ mice had beneficial effects in preventing the collagen accumulation in the skin and suppressing the autoimmunity via improvement of Th1/Th2 balance. The present study suggests that the IL-12 encoding plasmid administration might have a therapeutic effect on systemic sclerosis. 相似文献
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114.
Kamei K Wu X Xu X Minami K Huy NT Takano R Kato H Hara S 《Analytical biochemistry》2001,295(2):203-213
Evanescent wave biosensor has been recently employed as a powerful tool for analyses of macromolecular interactions. In the present study, evanescent wave biosensor analysis was developed to analyze the heparin-protein interaction using as ligands a series of heparin derivatives regioselectively desulfated by chemical methods, particularly to evaluate the effect of each sulfate group of heparin. The method for immobilizing heparin on the cuvette of the evanescent wave biosensor equipment was optimized to obtain the high response required for accurate measurement. The best result was achieved when the amino group introduced at the reducing end of heparin was coupled with carboxymethyl dextran on the surface of the cuvette using glycolchitosan as a multivalent linker. The established system appeared to describe well the interactions of heparin with such proteins as acidic and basic fibroblast growth factors and tissue factor pathway inhibitor. 相似文献
115.
Immune response induced by airway sensitization after influenza A virus infection depends on timing of antigen exposure in mice 总被引:2,自引:0,他引:2 下载免费PDF全文
Yamamoto N Suzuki S Suzuki Y Shirai A Nakazawa M Suzuki M Takamasu T Nagashima Y Minami M Ishigatsubo Y 《Journal of virology》2001,75(1):499-505
To study which phase of viral infection promotes antigen sensitization via the airway and which type of antigen-presenting cells contributes to antigen sensitization, BALB/c mice were sensitized by inhalation of ovalbumin (OA) during the acute phase or the recovery phase of influenza A virus infection, and then 3 weeks later animals were challenged with OA. The numbers of eosinophils and lymphocytes, the amounts of interleukin-4 (IL-4) and IL-5 in the bronchoalveolar lavage fluid, and the serum levels of OA-specific immunoglobulin G1 (IgG1) and IgE increased in mice sensitized during the acute phase (acute phase group), while a high level of gamma interferon production was detected in those sensitized during the recovery phase (recovery phase group). In the acute phase group, both major histocompatibility complex class II molecules and CD11c were strongly stained on the bronchial epithelium; in the recovery phase group, however, neither molecule was detected. OA-capturing dendritic cells (DCs) migrated to the regional lymph nodes, and a small number of OA-capturing macrophages were also observed in the lymph nodes of the acute phase group. In the recovery group, however, no OA-capturing DCs were detected in either the lungs or the lymph nodes, while OA-capturing macrophages were observed in the lymph nodes. These results indicate that the timing of antigen sensitization after viral infection determines the type of immune response. 相似文献
116.
Nakamura T Houchi H Minami A Sakamoto S Tsuchiya K Niwa Y Minakuchi K Nakaya Y 《Life sciences》2001,69(15):1709-1715
The relaxation effect of cilostazol, a phosphodiesterase III inhibitor, on the thoracic aorta was investigated. Cilostazol induced the relaxation of the thoracic aorta precontracted by phenylephrine in a concentration-dependent manner. The concentration-dependent relaxation was shifted to the right in the endothelium denuded aorta compared with that of intact endothelium, suggesting that this relaxation was partly dependent on endothelium. Cilostazol-induced relaxation of thoracic aorta tone was reversed by treatment with N(G)-nitro L-arginine (L-NNA), a competitive inhibitor of nitric oxide (NO) synthase. Cilostazol also significantly increased the NO level in the porcine thoracic aorta. In rats treated with cilostazol, the urinary excretion of nitrites, a stable metabolite of NO, and basal production of NO of the aortic ring were significantly greater than in those without treatment. These findings indicate that cilostazol-induced vasodilation of the rat thoracic aorta was dependent on the endothelium, which released NO from aortic endothelial cells. 相似文献
117.
Triterpene and flavanone glycoside from Rhododendron simsii 总被引:2,自引:0,他引:2
Antioxidative substances were isolated from the leaves of Rhododendron simsii. These were a triterpene and flavanone glycoside, together with the known matteucinol and two known benzoic acid derivatives. Their structures were characterized as 19,24-dihydroxyurs-12-en-3-one-28-oic acid and 7-O-beta-D-apiofuranosyl-(1-->6)-beta-D-glucopyranosylmatteucinol by spectroscopic analysis. 相似文献
118.
Manabu Yamamoto Satoshi Okumura Carsten Schwencke Junichi Sadoshima Yoshihiro Ishikawa 《The Histochemical journal》1999,31(4):241-243
A high efficiency transfection protocol employing a common polycationic lipid is described. Using LipofectAMINE, a widely used transfection reagent, we transfected 293T cells with a plasmid harboring the -galactosidase (-gal) gene. The transfection efficiency was determined by direct staining for X-gal. The conventional transfection protocol achieved an efficiency of <40% while our protocol, which employs the repetition of transfection a few times, achieved an efficiency of approximately 80%. Thus, a dramatic increase in transfection efficiency can be obtained by simply repeating transfection with the use of a common polycationic lipid. This method will be useful in many molecular biological experiments. 相似文献
119.
Tohno S Tohno Y Masuda M Minami T Moriwake Y Utsumi M Yamada M 《Biological trace element research》1999,70(3):233-241
It is known that a large quantity of magnesium contains bones, and the magnesium contents in spongy bones decrease gradually
with advancing age. To elucidate the relationships between a decrease of mineral contents in human bones and an accumulation
of minerals in the other human tissues, the content of magnesium was analyzed by inductively coupled plasma-atomic emission
spectrometry among human bones, arteries, veins, and cartilages in 27 subjects (17 men and 10 women). These were resected
from the subjects who died in the age range 40–98 yr. Calcanei were chosen for analysis of magnesium contents in contrast
with femoral, popliteal, and common carotid arteries, internal jugular and femoral veins, superior and inferior venae cavae,
and pubic symphyses.
The magnesium contents in the calcanei decreased gradually with aging, whereas they increased progressively in the arteries,
veins, and pubic symphyses with aging. It was found that as the magnesium contents decreased in the calcanei, they increased
in the arteries, such as the femoral, popliteal, and common carotid arteries, whereas they decreased inversely in the veins,
such as the internal jugular and femoral veins and superior and inferior venae cavae. Furthermore, as the magnesium contents
decreased in the calcanei, they hardly changed in the pubic symphyses. These suggest that magnesium released from bones is
accompanied by accumulation of magnesium in the arteries. 相似文献
120.
Utsumi M Tohno S Minami T Okazaki Y Moriwake Y Yamada M Tohno Y 《Biological trace element research》1999,67(2):165-171
On age relationships of mineral contents in human bones, the contents of the sixth rib and a piece of its compact bone were determined by inductively coupled plasma atomic emission spectrometry (ICPS). The ribs were resected from 21 subjects (14 men and 7 women) who died in age ranging from 65 to 93 yr. There were no age-dependent decreases in Ca and P contents of the ribs in the age range on ICPS. It was found that there were no age-dependent decreases in Ca and P in compact bones of ribs. 相似文献