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991.
We recently established a cell line (designated 371M) derived from an ovarian mucinous cystadenocarcinoma. The tumor cells were obtained from the ascitic fluid of a 54-year-old Japanese woman while she was undergoing surgery. Adjuvant chemotherapy (combined paclitaxel and carboplatin) was administered, but was ineffective, and she died about 4 months after surgery. The 371M cells continuously propagated in vitro over a period of about 50 months and, to date, have undergone over 100 passages. They proliferated in a monolayered sheet with doubling times of 84 h and 37 h in the 10th and 34th passages, respectively. When transplanted into nude mice, the tumor histopathologically resembled the structure of the original tumor. The 371M cells secreted high levels of CA125 and CA19-9 into the culture medium. There were several abnormal chromosomes in all karyotypes selected at random. Sensitivity of 371M cells to a variety of anti-cancer drugs was examined by in vitro MTT assay, and the results suggested that CPT-11 and CDDP were more effective against 371M cells than other anti-cancer agents.  相似文献   
992.
Hosaka K  Sato K 《Human cell》2002,15(4):224-229
This study was carried out to transform embryonic stem (ES) cells and to produce the reconstituted embryos derived from transgenic ES cell nuclei. Then, in vitro/vivo developmental potency of transgenic ES cells were compared to that of control ES cells (non-transgenic ES cells) in the reconstituted embryos. Unfertilized B6D2F1 ooplasm at metaphase II (M II) and two kinds of ES cell lines, 129SV and transgenic (tg) 129SV transformed by EGFP gene, were used as nuclear recipients and nuclear donors, respectively. The M II chromosome-spindle complex was aspirated into the pipette with a minimal volume of ooplasm. After enucleation, the ES cell nuclei was injected into the enucleated ooplasm directly. Then, reconstituted embryos were activated in SrCl2, and they were cultured in HTF medium. There was no difference of developmental rate between reconstituted embryos derived from the control (non-transgenic) and the tg ES cells. From this result, we indicated that transgenic ES cells might not change the property of peculiarity of the ES cell by gene transfer. The expression of GFP gene in the embryos was observed by fluorescence microscope at the 4-cell and more stage. As comparison with development of the embryos derived from the control and tg ES cells, the difference of the development could not be confirmed between the two cell groups. When the reconstituted embryos derived from the control and tg ES cells were transferred into oviduct or uterus of pseudopregnant females, fetuses were observed 13.5 days post coitum. However, in all fetuses, developmental arrest and regression were seen 19.5 days post coitum.  相似文献   
993.
The gene that encodes a thermostable endo-arabinase (called ABN-TS) from Bacillus thermodenitrificans TS-3 was cloned, sequenced, and expressed in the mesophilic B. subtilis. The gene contained an open reading frame consists of 939 bp, which encodes 313 amino acids. The deduced amino acid sequence of the enzyme showed 50, 46, and 36% similarity with endo-arabinase from B. subtilis IFO 3134 (PPase-C), Pseudomonas fluorescens (ArbA), and Aspergillus niger (ABNA), respectively. The hydrophobic and acidic amino acids making up ABN-TS outnumbered those in PPase-C. The gene product expressed in B. subtilis, as the host, had substantially the same characteristics, and was stable up to 70 degrees C, and the reaction was optimal around 70 degrees C, as well as native ABN-TS.  相似文献   
994.
Mouse model of Prinzmetal angina by disruption of the inward rectifier Kir6.1   总被引:19,自引:0,他引:19  
The inwardly rectifying K(+) channel Kir6.1 forms K(+) channels by coupling with a sulfonylurea receptor in reconstituted systems, but the physiological roles of Kir6.1-containing K(+) channels have not been determined. We report here that mice lacking the gene encoding Kir6.1 (known as Kcnj8) have a high rate of sudden death associated with spontaneous ST elevation followed by atrioventricular block as seen on an electrocardiogram. The K(+) channel opener pinacidil did not induce K(+) currents in vascular smooth-muscle cells of Kir6.1-null mice, and there was no vasodilation response to pinacidil. The administration of methylergometrine, a vasoconstrictive agent, elicited ST elevation followed by cardiac death in Kir6.1-null mice but not in wild-type mice, indicating a phenotype characterized by hypercontractility of coronary arteries and resembling Prinzmetal (or variant) angina in humans. The Kir6.1-containing K(+) channel is critical in the regulation of vascular tonus, especially in the coronary arteries, and its disruption may cause Prinzmetal angina.  相似文献   
995.
The purposes of this study were to examine the characteristics of the relationship between ADL ability and daily life satisfaction and the pattern change with aging in independent Japanese elderly, and to compare these tendencies between males and females. The characteristics of ADL ability and daily life satisfaction of 482 subjects (213 males, 269 females) were investigated in a self-response survey. Seventy-four ADL items, considered from previous studies, were selected from nine ADL domains of 1) movement, 2) going up and down stairs, 3) changing and holding posture, 4) bathing, 5) toileting, 6) dressing, 7) grooming, 8) eating, and 9) manual activities, and nine items of daily life satisfaction were selected from physical, psychological and sociological factors. Both ADL ability and life satisfaction of independent elderly tended to decline with aging. From correlation analysis, since life satisfaction of the elderly was higher with high ADL ability level, it was considered that ADL ability level is one of the important factors in providing for life satisfaction of independent elderly. The subjective symptoms of inconvenience in the lower extremity and lumbar region increased from the 70s in both genders, and the use of assisting devices for movement remarkably increased in the 80s in both genders. The use of assisting devices closely related to the activity area in daily life and influenced the characteristics of life satisfaction and its age-related change in the relationship between ADL ability and life satisfaction. The relationship between ADL ability and satisfaction with physical function was similar in both genders, while the relationship between ADL ability and satisfaction with sociological and psychological factors was different between males and females. Since the relationship between ADL ability and life satisfaction of independent elderly is influenced by a combination of personal, cultural, and environmental factors, additional study must investigate in detail the influence of these factors.  相似文献   
996.
997.
We have reported that treatment of melanoma patients with a vaccine consisting of autologous tumor cells modified with the hapten, dinitrophenyl (DNP) and preceded by low-dose cyclophosphamide induces delayed-type hypersensitivity (DTH) to autologous, unmodified tumor cells and that this response is a significant predictor of survival. We analyzed the vaccines prepared for 284 patients who were treated following resection of regional or distant metastases to find out whether the dose and composition determined the immunological response. A positive DTH response (> or =5 mm induration) to unmodified autologous tumor cells was induced in 57% of the patients (median: 5 mm; range: 0-22 mm). Regression analysis showed no significant association between the magnitude of DTH and the number of live (trypan blue exclusion) melanoma cells per dose over a dosage range of 0.5-25.0 x 10(6). Surprisingly, there was a small but significant positive relationship between the mean number of dead cells in the vaccines of a given patient and that patient's maximum DTH to unmodified melanoma cells. Only 37% of patients whose vaccines contained >50% live cells developed DTH, as compared with 69% and 65% of patients whose vaccines contained 26% to 50% or < or =25% live cells, respectively. Thus, it appears that dead tumor cells contribute to the immunogenicity of the DNP vaccine, but other factors such as the administration schedule may be more important determinants of immunological and clinical outcome.  相似文献   
998.
Gastric intestinal metaplasia occurs as a pathological condition in the gastric mucosa. To clarify how an intestine-specific homeobox gene, Cdx2, affects the morphogenesis of gastric mucosa, we generated transgenic mice expressing Cdx2 in parietal cells. Until Day 18 after birth, the number of parietal cells inthegastric mucosa of transgenic mice was the same as for their normal littermates. However, at Day 19, we detected several glands in which parietal cells disappeared and the proliferating zone moved from the isthmus to the base of the glands. Thereafter, parietal cells decreased gradually and disappeared at Day 37. All of the gastric mucosal cells, except for enterochromaffin-like (ECL) cells, were completely replaced by intestinal metaplasia, consisting of goblet cells, enteroendocrine cells, and absorptive cells expressing alkaline phosphatase. Pseudopyloric gland metaplasia was also formed. The transgenic mouse is a very useful model for clarifying physiological differentiation of gastric and intestinal cell lineages and analyzing the molecular events from intestinal metaplasia to adenocarcinoma.  相似文献   
999.
Pleiotrophin (PTN) is an extracellular matrix-associated growth/differentiation factor that, in post-natal life, is found mainly in bone and brain. Bone development was investigated in ptn-overexpressing mice between 1 and 30 weeks. In transgenics and controls, PTN (and its receptor syndecan-3) was synthesized by osteoblasts and was present in striated muscle. ptn over-expression enhanced intramembranous bone formation and had multiple effects on long-term bone growth. The pubertal growth spurt did not take place in transgenic mice, in which the growth trajectory was steady and continuous until 25 weeks. By 30 weeks, transgenic and control mice were of the same size, but the calcium content/mg bone was approximately 10% higher in the transgenics. PTN was also localized in growth plate and articular chondrocytes, but only in transgenic mice. In these, synthesis of type I collagen by articular chondrocytes was observed, as well as an encroachment of subchondral bone into the articular cartilage. The results suggest that PTN has multiple roles during in vivo bone formation and remodeling, probably acting as a co-factor or accessory protein that modulates the effects of primary signaling molecules.  相似文献   
1000.
Regional gene therapy, which involves the delivery of growth factors to a specific anatomic site, has the potential to enhance bone formation in clinical application. Helper-dependent adenoviral vectors, which have deleted all of the viral coding regions, have been shown to be safe and highly efficient with long-lasting transgene expression. In this study, we constructed a helper-dependent adenoviral vector producing bone morphogenetic protein-2 (AdHDBMP-2). The AdHDBMP-2 increased the alkaline phosphatase activity of W-20-17 cells in vitro. In addition, when AdHDBMP-2 infected rat bone marrow cells were implanted into the hindlimbs of SCID mice, orthotopic bone formation was shown at 2 weeks. To our knowledge, this is the first study to demonstrate bone formation with the helper-dependent adenoviral vector with the BMP-2 expression cassette. This type of gene therapy vector could prove to be highly useful for bone augmentation in patients with bone loss associated with trauma, revision total joint arthroplasty, or cancer.  相似文献   
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