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81.
Murine macrophage interleukin-1 release by capsularlike serotype-specific polysaccharide antigens of Actinobacillus actinomycetemcomitans. 总被引:2,自引:6,他引:2
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T Takahashi T Nishihara Y Ishihara K Amano N Shibuya I Moro T Koga 《Infection and immunity》1991,59(1):18-23
Serotype-specific polysaccharide antigens (SPAs) were extracted from whole cells of Actinobacillus actinomycetemcomitans ATCC 29523 (serotype a), Y4 (serotype b), and NCTC 9710 (serotype c) by autoclaving and purified by chromatography on DEAE-Sephadex A-25 and Sephacryl S-300 columns. Y4 SPA induced interleukin-1 (IL-1) release by P388D1 murine macrophages. Polymyxin B had virtually no effect on the release of IL-1. Rabbit anti-murine IL-1 serum strongly suppressed the proliferation of C3H/HeJ mouse thymocytes induced with the culture supernatants of Y4 SPA-stimulated P388D1 cells and a submitogenic dose of concanavalin A. Gel filtration of the culture supernatants of Y4 SPA-stimulated macrophages on Sephacryl S-200 showed that an IL-1 peak at a point corresponding to approximately 16.5 kDa was eluted. The ability of SPAs from strains ATCC 29523 and NCTC 9710 to induce the release of IL-1 was lower than that of Y4 SPA. The IL-1-releasing ability of serotype a and c antigens was enhanced by deacetylation of both polysaccharides, suggesting that acetyl groups of these antigens might hinder the interaction between the antigens and macrophages. 相似文献
82.
An invasion-independent pathway of blood-borne metastasis: a new murine mammary tumor model
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Sugino T Kusakabe T Hoshi N Yamaguchi T Kawaguchi T Goodison S Sekimata M Homma Y Suzuki T 《The American journal of pathology》2002,160(6):1973-1980
It is generally believed that active invasion by cancer cells is essential to the metastatic process. In this report, we describe a murine mammary tumor (MCH66) model of metastasis that does not require invasion into the vascular wall of both the primary tumor and the target organ, in this case, the lung. The process involves intravasation of tumor nests surrounded by sinusoidal blood vessels, followed by intravascular tumor growth in the lung, without penetration of the vascular wall during the process. Comparative studies using a nonmetastatic MCH66 clone (MCH66C8) and another highly invasive metastatic cell line (MCH416) suggested that high angiogenic activity and sinusoidal remodeling of tumor blood vessels were prerequisites for MCH66 metastasis. Differential cDNA analysis identified several genes that were overexpressed by MCH66, including genes for the angiogenesis factor pleiotrophin, and extracellular matrix-associated molecules that may modulate the microenvironment toward neovascularization. Our analyses suggest that tumor angiogenesis plays a role in the induction of invasion-independent metastasis. This model should prove useful in screening and development of new therapeutic agents for cancer metastasis. 相似文献
83.
Depression of delayed-type hypersensitivity in mice with hypothalamic lesion induced by monosodium glutamate: involvement of neuroendocrine system in immunomodulation.
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K Kato N Hamada N Mizukoshi K Yamamoto T Kimura C Ishihara Y Fujioka T Kato K Fujieda N Matsuura 《Immunology》1986,58(3):389-395
Delayed-type hypersensitivity (DTH) was depressed in mice that had been treated with monosodium glutamate (MSG) in their suckling period. Analysis of the DTH depression by use of the macrophage migration inhibition assay showed dysfunction of DTH effector T cells. The neuronal loss of nuclei in the hypothalamus, which elaborates the corticotropin-releasing factor and the hypersecretion of adrenocorticotrophic hormone, was observed in the MSG-treated mice. Therefore, DTH response may be modulated by the neuroendocrine system. 相似文献
84.
Antifouling blood purification membrane composed of cellulose acetate and phospholipid polymer 总被引:7,自引:0,他引:7
The ideal surface of an artificial blood purification membrane needs hemocompatibility and durability of high performance; it should not adsorb any proteins or cells but should still have high permeability in the desired range of solute size. To improve the anti-fouling property of cellulose acetate (CA) membranes, a CA membrane blended with poly(2-methacryloyloxyethyl phosphorylcholine (MPC)-co-n-butyl methacrylate (BMA)) (PMB30) was designed as a blood purification membrane. The polymer solutions for preparing the membrane were prepared using a solvent mixture composed of N, N-dimethylformamide, acetone, 2-propanol or water. The CA and CA/PMB30 blend membranes with an asymmetric and porous structure were prepared by a phase inversion process.The characteristics of the CA/PMB30 blend membrane, such as structural properties, mechanical properties, and solute permeability were examined with attention to changes in the preparation conditions of the membrane. The CA/PMB30 blend membrane had good water and solute permeability and a sharp molecular weight cut-off property. Moreover, the amount of proteins adsorbed on the CA/PMB30 blend membrane surface was less than that of the original CA membrane and a conventional polysulfone membrane. Adhesion and activation of platelets on the CA/PMB30 blend membrane were reduced compared with that on a CA membrane. In addition, the CA/PMB30 blend membrane showed good permselectivity and an antifouling property during a long time ultrafiltration experiment with protein solutions. 相似文献
85.
The patterns of DNA degradation in frozen, methanol-fixed, and formalin-fixed tissues were investigated by high-performance liquid chromatography (HPLC). The chromatograms all yielded one major peak with or without several extra minor peaks representing molecular weights of preserved genomic DNA. The most characteristic differences were in the retention times of the major peaks, with the earliest major peak occurring in the formalin-fixed tissues, and followed by the methanol-fixed, and frozen tissue samples, in that order. This means that the molecular weight of the DNA from formalin-fixed tissue is much shortened than that recovered from methanol-fixed tissue and frozen tissue. The results also indicated that a small amount of higher molecular weight DNA is still preserved in formalin-fixed tissues. To improve the amplification efficiency of polymerase chain reaction (PCR) analysis of formalin-fixed material, we isolated the higher molecular weight DNA from formalin-fixed, paraffin-embedded tissue from four different organs and compared the amplification efficiencies with those of the crude DNA extract. We used eight sets of oligonucleotide primers producing 262 to 989 base pair (bp) fragments of beta-globin. The results showed that the PCR amplification analyses were more efficient with the isolated higher molecular weight DNA than with the crude DNA extract. Our study demonstrated that not all the DNA in formalin-fixed, paraffin-embedded tissue samples is totally degraded but that a small amount of higher molecular weight DNA persists. The feasibility of molecular diagnosis using formalin-fixed material can be improved by isolating the preserved higher molecular weight DNA by HPLC. 相似文献
86.
Otsuka Y Ito M Yamaguchi M Saito S Uesu K Kasai K Abiko Y Mega J 《Mechanisms of ageing and development》2002,123(6):663-674
It is well known that Down syndrome (DS) is a premature ageing syndrome. Periodontal disease in individuals with DS develops rapidly and extensively in a relatively younger age bracket compared with that in healthy controls. The mechanisms involved in the periodontal inflammatory processes in DS patients are not fully understood. In the present study, the non-inflamed gingival fibroblasts isolated from seven patients with DS (DGF) and seven healthy controls (NDGF) were stimulated with lipopolysaccharide (LPS) derived from Actinobacillus actinomycetemcomitans (A. a.). We measured the level of prostaglandin E2 (PGE2) production by DGF and NDGF by radioimmunoassay, and also measured the mRNA expression of cyclooxygenase-1 (COX-1) and cyclooxygenase-2 (COX-2) by using the real-time PCR method. We found the higher levels of LPS-stimulated COX-2 mRNA expression and PGE2 production in DGF when compared with those in NDGF. This study may indicate that overexpression of LPS-stimulated COX-2 induced a greater ability of DGF to produce PGE2, and that these phenomena may be responsible for the severer periodontal disease in DS patients. 相似文献
87.
Preparation of a protein micro-array using a photo-reactive polymer for a cell-adhesion assay 总被引:4,自引:0,他引:4
A protein micro-array, called a "cell chip" was constructed by using a photo-reactive polymer for a cell-adhesion assay. Various amounts of albumin or fibronectin were covalently immobilized on a polystyrene dish using a micro-spotter with a dip pen. First, poly(acrylic acid) carrying azidophenyl groups was synthesized as the photo-reactive polymer. Secondly, the aqueous solution of a photo-reactive polymer (several nanoliters) was cast using the dip pen of the micro-spotter and dried in air. Subsequently, aqueous solutions of proteins were cast on the same place using the micro-spotter. After drying, the dish was irradiated with ultraviolet light. Finally, the immobilization was confirmed by staining with a dye. The immobilization was stable even after washing with Tween-20. The protein-immobilized area depended on the manipulation of the micro-spotter and the size of the dip pen. Subsequently, cell adhesion on the photo-immobilized protein micro-array was investigated. The adhesion behavior of cells depended on the kind of immobilized proteins and the kind of cells. The protein micro-array will be useful for cell diagnosis and for the selection of biomaterials to regulate cell behavior. 相似文献
88.
A surgical case of proliferative funiculitis (pseudosarcomatous myofibroblastic proliferation of the spermatic cord) with a prominent mast cell infiltration is reported. A 67-year-old man with a history of right inguinal herniorrhaphy 7 years earlier was operated on for diffuse swelling of the inguinal region and scrotum. A large lipoma was found in the inguinal region, and a nodular lesion, measuring 2.7 cm in maximal dimension, was firmly attached to the right spermatic cord. The nodular lesion showed diffuse proliferation of fibroblasts and myofibroblasts associated with the deposition of collagen. A diffuse infiltration of numerous mast cells was found throughout the lesion. Lesions that belong to the group of inflammatory pseudotumors are rarely accompanied by a prominent mast cell infiltration, and the differentiation from mast cell neoplasms is often problematic in such cases. The present case is the first example of proliferative funiculitis associated with this rare phenomenon. 相似文献
89.
Quantitative Analysis of Mycobacterial and Propionibacterial DNA in Lymph Nodes of Japanese and European Patients with Sarcoidosis 总被引:10,自引:0,他引:10
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Yoshinobu Eishi Moritaka Suga Ikuo Ishige Daisuke Kobayashi Tetsuo Yamada Tamiko Takemura Touichiro Takizawa Morio Koike Shoji Kudoh Ulrich Costabel Josune Guzman Gianfranco Rizzato Marcello Gambacorta Ronald du Bois Andrew G. Nicholson Om P. Sharma Masayuki Ando 《Journal of clinical microbiology》2002,40(1):198-204
The cause(s) of sarcoidosis is unknown. Mycobacterium spp. are suspected in Europe and Propionibacterium spp. are suspected in Japan. The present international collaboration evaluated the possible etiological links between sarcoidosis and the suspected bacterial species. Formalin-fixed and paraffin-embedded sections of biopsy samples of lymph nodes, one from each of 108 patients with sarcoidosis and 65 patients with tuberculosis, together with 86 control samples, were collected from two institutes in Japan and three institutes in Italy, Germany, and England. Genomes of Propionibacterium acnes, Propionibacterium granulosum, Mycobacterium tuberculosis, Mycobacterium avium subsp. paratuberculosis, and Escherichia coli (as the control) were counted by quantitative real-time PCR. Either P. acnes or P. granulosum was found in all but two of the sarcoid samples. M. avium subsp. paratuberculosis was found in no sarcoid sample. M. tuberculosis was found in 0 to 9% of the sarcoid samples but in 65 to 100% of the tuberculosis samples. In sarcoid lymph nodes, the total numbers of genomes of P. acnes or P. granulosum were far more than those of M. tuberculosis. P. acnes or P. granulosum was found in 0 to 60% of the tuberculosis and control samples, but the total numbers of genomes of P. acnes or P. granulosum in such samples were less than those in sarcoid samples. Propionibacterium spp. are more likely than Mycobacteria spp. to be involved in the etiology of sarcoidosis, not only in Japanese but also in European patients with sarcoidosis. 相似文献
90.
The effects of hyperbaric exposure with high oxygen concentration on spinal motoneurons and the skeletal muscle fibers that they innervate were investigated. Five-week-old male rats were exposed to a hyperbaric (1.25 atmospheric pressure) environment with a high oxygen concentration (35.0%) for 6h daily. The number, cell body size, and oxidative enzyme activity of motoneurons innervating the soleus and plantaris muscles were examined after 8 weeks of hyperbaric exposure. In addition, the fiber type distribution, cell size, and oxidative enzyme activity of the slow soleus and fast plantaris muscles were examined. The oxidative enzyme activity of alpha motoneurons innervating the soleus and plantaris muscles increased after hyperbaric exposure, irrespective of their cell body sizes. The percentage of high-oxidative fibers in the soleus and plantaris muscles increased after hyperbaric exposure. The oxidative enzyme activity of all types of fibers in the soleus and plantaris muscles increased after hyperbaric exposure. It is concluded that hyperbaric exposure with high oxygen concentration enhances the oxidative capacity of neuromuscular units. 相似文献