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61.
Takahiko Hara Masatake Yamauchi Ei-ichi Takahashi Masato Hoshino Kazuhisa Aoki Dai Ayusawa Masao Kawakita 《Somatic Cell and Molecular Genetics》1993,19(6):571-575
We have cloned a segment of the human gene encoding UDP-galactose translocator by genetic complementation of its defective mutant in mouse FM3A cells. Chromosome mapping using fluorescentin situ hybridization revealed that the cloned gene hybridized to the Xp11.23-11.23 region of the X chromosome. This region is shared by the locus of Wiskott-Aldrich syndrome, an X-linked recessive immunodeficiency disorder, characterized by defective sugar chains on cell surface components. Genetic and phenotypic similarities suggest a possible link between UDP-galactose translocator and the Wiskott-Aldrich syndrome (WAS). 相似文献
62.
Masahiko Kuroda Hajime Horiuchi Teruaki Oka Tsuyoshi Ishida Akira Ono Masao Kawakita Rikuo Machinami 《Virchows Archiv : an international journal of pathology》1993,423(3):209-213
Ninety-one cases of human bone and soft tissue tumours were studied for calcium pump expression by strepto-avidin-biotin immunohistochemical staining with a monoclonal antibody against sarcoplasmic reticulum calcium-ATPase (mAb6F5). Two out of 5 cases of embryonal rhabdomyosarcoma, 1 out of 5 cases of biphasic synovial sarcoma, 4 of 4 cases of chordoma and all of 3 chondrosarcoma cases were positive for mAb6F5. Although this novel monoclonal antibody can be used as a marker of myogenic tumours, the present positive result for endoplasmic reticulum calcium-ATPase (calcium pump) in other tumours including chordoma, chondrosarcoma and synovial sarcoma indicates a wider immunoreactivity. The findings further suggest that intracellular calcium may play an important role in cell proliferation and/or differentiation. 相似文献
63.
Breast milk macrophages spontaneously produce granulocyte-macrophage colony-stimulating factor and differentiate into dendritic cells in the presence of exogenous interleukin-4 alone
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Ichikawa M Sugita M Takahashi M Satomi M Takeshita T Araki T Takahashi H 《Immunology》2003,108(2):189-195
Peripheral blood monocytes extravasate and differentiate into tissue macrophages to mediate effective local defence, but how tissue-specific stimuli and environments may influence their functions remains unknown. Here, we found that peripheral blood monocytes gained the ability to produce granulocyte-macrophage colony-stimulating factor (GM-CSF) upon exposure to breast milk and differentiated into CD1+ dendritic cells (DCs) in the presence of exogenous interleukin-4 (IL-4) alone. This in vitro observation appeared physiologically relevant since macrophages that were freshly isolated from breast milk were also found to produce GM-CSF spontaneously. Furthermore, in contrast to peripheral blood monocytes that differentiated into DCs only in the presence of both exogenous GM-CSF and IL-4, differentiation of breast milk macrophages into DCs was induced by incubation with exogenous IL-4 alone. These IL-4-stimulated breast milk macrophages were efficient in stimulating T cells, suggesting their potential role in mediating T-cell-dependent immune responses in situ. On the other hand, unexpected expression of DC-SIGN, a DC-specific receptor for human immunodeficiency virus (HIV), even in unstimulated breast milk macrophages, may favour HIV infection, resulting in an increased risk of mother-to-infant vertical transmission of the virus via breast milk. Thus, tissue-specific development of macrophages is often linked to effective local immunity, but may potentially provide an opportunity for a pathogen to spread and transmit. 相似文献
64.
Yoshida M Torigoe S Ikeue K Yamada M 《Clinical and diagnostic laboratory immunology》2002,9(2):388-393
Seroprevalence of human herpesvirus 6 (HHV-6) and HHV-7 infections is very high throughout the world, and almost all people are exposed first to HHV-6 and second to HHV-7 in their childhood. However, it is not clear whether the neutralizing (NT) antibody response between each virus is cross-reactive or not. To elucidate the NT antibody response between each virus, 55 serum samples from an adult group (subjects 22 to 88 years old) and 60 serum samples from a young group (subjects 2 to 18 years old) were examined by a dot blot method for detecting viral late antigen. Thirty-nine serum samples obtained from cord bloods and a few serum samples obtained from pediatric patients with exanthem subitum were also examined to assess the maternal transferred NT antibodies against each virus. The NT antibody titers against HHV-7 in the adult group remained high throughout all the individuals, and none were negative. Those against HHV-6 were high values in the young group but low values, including negative values (three samples), in the adult group. These results suggested that the NT antibody response to either HHV-6 or HHV-7 in each individual was specific to each virus and did not cross-react with each other. In the adult group, the NT antibody response to HHV-6 decreased, while that to HHV-7 remained high throughout all the individuals. Maternal transferred NT antibody titers against HHV-7 were higher and remained longer after birth than those of HHV-6, and these findings were in accord with the clinical observation that HHV-6 infection usually occurs earlier than HHV-7 infection. 相似文献
65.
In the oxidative polymerization of 2,6-dimethylphenol ( 8 ) the catalytic activities of the following semiconducting organic polymeric metal complexes were studied: polymeric complexes containing bis(ethylene-1,2-dithiolato)Cu(II) or Fe(III) complexes and copper(II) phthalocyanine structures ( 3a – c ), catalysts consisting of bis(ethylene-1,2-dithiolato)-Cu(II) or Fe(III) complex structures and hemiporphyrazine type structures ( 5a – c ), and also polymers containing a copper complex of dimercaptomaleic acid monoamide ( 7 ). It was found that a suspension of the insoluble bis(ethylene-1,2-dithiolato)Cu(II) polymeric complexes of type 3 catalyzes the polymerization in the presence of oxygen in pyridine at room temperature producing poly[oxy-(2,6-dimethyl-1,4-phenylene)] ( 9 ) in very good yields. Polymeric complexes of type 5 were inactive by themselves. However, we showed that bis(ethylene-1,2-dithiolato)Cu(II) polymeric complexes of both the 3 and 5 type possess great activities if they are used in the presence of small amounts of copper(II)-pyridine complex in pyridine solution (the chosen concentration was so low that the Cu(II)-pyridine complex alone had only a small activity). Bis(ethylene-1,2-dithiolato)Fe(III) complexes of both the 3 and 5 type were inactive even in the presence of the Cu(II)-pyridine complex. 相似文献
66.
Hayakawa T Yoshinari M Nemoto K 《Journal of biomedical materials research. Part A》2003,67(2):684-688
The aim of this study was to bind fibronectin directly to a titanium surface treated with tresyl chloride (2,2,2-trifluoroethanesulfonyl chloride) for the development of a strong connection of a dental implant to subepithelial connective tissues and/or peri-implant epithelia. Basic terminal OH groups of mirror polished titanium were allowed to react with tresyl chloride at 37 degrees C for 2 days. The tresylated titanium disk was then immersed into a fibronectin/phosphate-buffered saline solution for 24 h at 37 degrees C. The activation reaction of the basic OH of titanium with tresyl chloride was confirmed by S2p, F1s, and O1s spectra using X-ray photoelectron spectroscopy and -O-S-O2- bonds using Fourier transform infrared reflection-absorption spectroscopy. After the reaction of fibronectin with titanium, the X-ray photoelectron spectroscopy revealed the remarkable effect of the activation of terminal OH groups with the tresyl chloride treatment. The N1s peak derived from the attached fibronectin still remained after 60 s of argon-ion sputtering after tresyl chloride treatment. In contrast, the N1s peak of the specimen not treated with tresyl chloride almost disappeared after only 10 s of argon-ion etching. Fibronectin, a well-known cell-adhesive protein, could easily be attached to the titanium surface by use of the tresyl chloride activation technique. 相似文献
67.
Saito A Suzuki Y Ogata S Ohtsuki C Tanihara M 《Journal of biomedical materials research. Part A》2004,70(1):115-121
Bone morphogenetic protein-2 (BMP-2) promotes the formation and regeneration of bone and cartilage, and therefore constitutes the most promising candidate for a bone repair material. However, it also has a wide range of functions, such as in organogenesis and apoptosis. Therefore, we investigated a novel synthetic peptide corresponding to residues 73-92 of BMP-2. This peptide bound to a BMP-2-specific receptor and elevated both alkaline phosphatase activity and osteocalcin mRNA in the murine cell line, C3H10T1/2. The 73-92 peptide also induced ectopic calcification when conjugated to a covalently crosslinked alginate gel. Here we report that the 73-92 peptide-conjugated alginate gel showed prolonged ectopic calcification for up to 7 weeks in rat calf muscle. In contrast, rhBMP-2-impregnated collagen gel showed maximum ectopic calcification at 3 weeks, and the calcified products that had formed disappeared after 5 weeks. Histological examination showed that the 73-92 peptide-conjugated alginate gel induced many osteoblast-like cells and few osteoclasts. In contrast, rhBMP-2-impregnated collagen gel induced many osteoclasts. These results suggest that the 73-92 peptide on alginate gel remains active at the implanted site, continuously induces differentiation of osteoblast precursor cells into osteoblasts, and activates osteoblasts to promote ectopic calcification. 相似文献
68.
Development of a rapid PCR method using the insertion sequence IS1203 for genotyping Shiga toxin-producing Escherichia coli O157 总被引:2,自引:0,他引:2
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Suzuki M Matsumoto M Hata M Takahashi M Sakae K 《Journal of clinical microbiology》2004,42(12):5462-5466
We developed a rapid PCR method utilizing the diversity of the insertion site IS1203 for genotyping Shiga toxin-producing Escherichia coli (STEC) O157 (IS1203 PCR typing). DNA fragments digested by PvuII, which cut IS1203 at one site, were ligated with themselves and detected by PCR with outward-facing primer pairs for IS1203. To minimize nonspecific bands, nested PCR was also performed. Two fingerprinting patterns produced from the upstream or downstream regions of IS1203 were obtained within 1 or 2 days. By combining the two patterns, 79 STEC O157 isolates were classified into 39 types, which were then classified into 36 subtypes by pulsed-field gel electrophoresis (PFGE). The discriminatory power of IS1203 PCR typing (D = 0.974) is similar to that of PFGE (D = 0.981). This method can be used for rapid and simplified genotyping. 相似文献
69.
In the gastric mucosa of Japanese patients, ciliated cells were found in association with intestinal metaplasia. The cells occurred frequently in the pyloric mucosa of nearly half of the cases examined but rarely in the cardiac mucosa of total 12 cases, but never adjacent to the chief cells of gastric glands. The ciliated cells were always found in the basal part of cardiac and pyloric glands, but never in the surface or in the foveolar epithelium. Furthermore, ciliated cells containing a few small mucus granules and simultaneously possessing numerous cilia and basal bodies were noted. Ciliated cells in the gastric mucosa have been found mainly in elderly Japanese patients, but were also observed exceptionally in one Chinese, two Swedes and one American. These ciliated cells are not present in the normal human gastric and intestinal mucosa, and therefore a new term, "ciliated metaplasia", is proposed for their occurrence. Acta Pathol Jpn 40: 98–106, 1990. 相似文献
70.
Fujii K Miyashita T Omata T Kobayashi K Takanashi J Kouchi K Yamada M Kohno Y 《American journal of medical genetics. Part A》2003,(1):65-68
We present the case of a 14-year-old Japanese girl who had both Gorlin syndrome and ulcerative colitis. She had complained of blood stools for 6 months and severe scoliosis from her infancy. Physical examination revealed multiple nevi, palmar and plantar pits, jaw cysts, and calcification of the falx cerebri, leading to the diagnosis of Gorlin syndrome. Total colonoscopy revealed an edematous and spotty bleeding mucosa extending from the anus to the transverse colon. Histological examination was also compatible with ulcerative colitis. Thus, we diagnosed her as having Gorlin syndrome with ulcerative colitis. Gene analysis revealed a mutation, 1247InsT, in the human patched gene (PTCH), resulting in the truncation of PTCH protein. Since Gorlin syndrome and ulcerative colitis are rare disorders in childhood, this association is interesting, suggesting a correlation between the hedgehog signaling and intestinal disorders. 相似文献