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71.
In this paper we describe the establishment and characterization of a transplantable cell line derived from a spontaneously occurring chondroblastic osteosarcoma in a C57BL/6J mouse. The tumor line, MOS-J, forms solid tumors when injected intramuscularly into immunocompetent syngeneic hosts, mimicking endochondral bone development. These transplantable tumors have the capacity to destroy and invade existing bone and invade vessels in close proximity to the tumor. In culture, MOS-J cells form layers of pleomorphic cells with high mitotic activity. These cells have marked alkaline phosphatase activity and form calcified foci in vitro that stain with alizarin red. MOS-J cells also promote osteoclast development in vitro from normal bone marrow cells. These characteristics indicate the potential utility of the MOS-J osteosarcoma cell line as a model for studies of human osteosarcoma and bone biology.  相似文献   
72.
A novel single nucleotide polymorphism (SNP) was found in exon 6 of the UDP-glucuronosyltransferase (UGT) 2B15 gene from healthy Japanese populations. The SNP was as follows: SNP, 020228Toide001; GENE NAME, UGT2B15; ACCESSION NUMBER, U08854, AF180322, and NM_001078; LENGTH, 25 base; 5'-AGCTTGCCAAAAC/AAGGAAAGAAGAA-3'. This SNP was expected to cause a change of an amino acid residue at the position 523 (Thr to Lys) located in a putative co-factor binding region. The allele frequency of this SNP was 79% in Japanese, suggesting this polymorphism to be a major genotype in Japanese people.  相似文献   
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A rare case of retroperitoneal bronchogenic cyst is presented. A 50-year-old man was referred to our hospital for an investigation of a retroperitoneal mass. Computed tomography and magnetic resonance imaging confirmed a retroperitoneal mass, about 4 cm in diameter, adjacent to the left kidney and spleen. On the basis of these imaging modalities, a definitive diagnosis of this mass could not be made. So, resection of the mass was performed. The removed mass was an unilocular cyst and filled with mucinous fluid. Histopathologically, the cyst wall was composed of a fibrovascular connective tissue containing mucus-secreting glands and cartilages and was lined by ciliated pseudostratified columnar epitherium. Thus, a diagnosis of bronchogenic cyst was made. Bronchogenic cysts are rare congenital anomalies of the primitive foregut and usually develop in the mediastinum and lung.  相似文献   
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We have investigated the relationship between the developmental expression of sphingomyelin, a major component of myelin, and oligodendrocyte lineage. Using lysenin as a cytochemical probe for membrane sphingomyelin, we have now determined the distribution pattern of sphingomyelin on the plasma membrane of rat cultured oligodendrocytes. Although lysenin does not bind to A2B5(+)/NG2(+) bipolar oligodendrocyte progenitors, lysenin recognizes sphingomyelin on the cell bodies of multipolar A2B5(+) cells, but not on their processes. O4(+) and O1(+) immature and MBP(+) mature oligodendrocytes are strongly labeled by lysenin from cell bodies to the tips of processes. The content of sphingomyelin in immature and mature oligodendrocytes is approximately 2-fold higher than that in oligodendrocyte progenitors. These findings show that sphingomyelin increases during differentiation of cells in the oligodendrocyte lineage. In multipolar oligodendrocyte progenitors exposed to Triton X-100 at 4 degrees C, lysenin labels cell processes in addition to cell bodies. In contrast, Triton X-100 extraction does not alter the distribution of lysenin binding on O4(+), O1(+) and MBP(+) cells, although the immunocytochemical intensities of the lysenin bindings increase. Our data suggest that the alteration in sphingomyelin content and distribution in the oligodendrocyte lineage cells could have important consequences for cell recognition and downstream signaling events through sphingomyelin-rich domains.  相似文献   
78.
Here we found that wortmannin sensitized Chinese hamster V79 cells to hyperthermic treatment at 44.0 degrees C as determined either by colony formation assay or by dye exclusion assay. Wortmannin enhanced heat-induced cell death accompanying cleavage of poly (ADP-ribose) polymerases (PARP). Additionally, the induction of heat shock protein HSP70 was suppressed and delayed in wortmannin-treated cells. Heat sensitizing effect of wortmannin was obvious at more than 5 or 10 microM of final concentrations, while radiosensitization was apparent at 5 microM. Requirement for high concentration of wortmannin, i.e., order of microM, suggests a possible role of certain protein kinases, such as DNA-PK and/or ATM among PI3-kinase family. The sensitization was minimal when wortmannin was added at the end of heat treatment. This was similar to the case of X-ray. Since heat-induced cell death and PARP cleavage preceded HSP70 induction phenomenon, the sensitization to the hyperthermic treatment was considered mainly caused by enhanced apoptotic cell death rather than secondary to suppression or delay by wortmannin of HSP70 induction. Further, in the present system radiosensitization by wortmannin was also at least partly mediated through enhancement of apoptotic cell death.  相似文献   
79.
The study aims to examine the relationship between habitual coffee consumption and blood pressure. The subjects were 3336 male self-defense officials aged 48–56 years, who received a preretirement health examination at the Self-Defense Forces Fukuoka Hospital between October 1986 and December 1992. Average coffee intake in the past year was ascertained by a self-administered questionnaire. A significant inverse relation between habitual coffee consumption and blood pressure was found with and without adjustment for alcohol use, cigarette smoking, body mass index, glucose tolerance, and green tea intake. Green tea, another major source of caffeine intake in Japanese, was unrelated to blood pressure. The adjusted mean differences per cup of coffee consumed per day were –0.6 mmHg (95% confident interval [CI]: –0.9 to –0.3, p=0.0001) in systolic blood pressure and –0.4 mmHg (95% CI: –0.5 to –0.2, p=0.0002) in diastolic blood pressure. Habitual coffee drinkers had lower blood pressure than non-drinkers at any levels of alcohol use, cigarette smoking, obesity, and glucose intolerance. Our findings consolidate the previous observation that habitual coffee consumption was associated with lower blood pressure.  相似文献   
80.
Abstract Although both CD80 (B7–1) and CD86 (B7–2/B70) have been recently identified in cultured human Langerhans cells (LC), little is known of the role and regulatory properties of CD80 and CD86 on human LC. We present here the results of a study comparing the expression and function of CD80 and CD86 in human LC using the T-helper type-1 cytokines IL-2 and interferon γ (IFN)-γ, and the T-helper type-2 cytokines IL-10, IL-4 and granulocyte/macrophage colony-stimulating factor (GM-CSF). Freshly isolated human LC expressed little CD80 and CD86 in vitro, but the expression of both molecules was rapidly induced during a 72-h incubation with cytokines and the expression of CD86 occurred much earlier and more strongly than that of CD80. The expression of both CD80 and CD86 was upregulated by GM-CSF and downregulated by IL-10, and the expression of CD86, but not that of CD80, was upregulated by both IL-4 and IFN-γ. Finally, pretreatment of LC with GM-CSF and IFN-γ, but not with IL-4, enhanced the alloreactive T-cell proliferation induced by the LC, and IL-10 pretreatment of LC decreased their capacity for alloreaction. These results indicate that the expression of both CD80 and CD86 on human LC may be regulated by these cytokines (IL-2, IL-4, GM-CSF, IFN-γ and IL-10) secreted from helper T cells infiltrating into the inflammatory microenvironment. Received: 4 December 1997  相似文献   
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