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11.
12.
Yoshio Oka Tetsuro Kobayashi Shoichi Fujita Nariaki Matsuura Shigeru Okamoto Hideki Asakawa Atsuo Murata Takesada Mori 《In vitro cellular & developmental biology. Animal》1993,29(7):537-542
Summary A human anaplastic thyroid cancer cell line K-119, derived from a 77-yr-old woman who had developed marked neutrophilia and
underwent surgery for anaplastic thyroid cancer, has been established. The spindlelike and polygonal cells in shape are stably
proliferating since the beginning of its culture 2 yr ago. The cells grow rapidly and the population doubling time is 26 h.
The chromosomes show many abnormalities and many marker chromosomes have been observed. Heterotransplantation of the cells
into nude mice has resulted in the formation of tumors that are histologically interpreted as anaplastic cancer. The most
noteworthy characteristics of the cell line are the many Ki-67-positive cells (86.3%) and that the cell line spontaneously
secretes granulocyte colony-stimulating factor (G-CSF) and releases increased amounts of G-CSF in response to the stimulation
of tumor necrosis factor, interleukin 1α, and interleukin 1β. The conditioned medium obtained from K-119 cells contains an
autocrine factor stimulating the proliferation of themselves. 相似文献
13.
R. CODDINGTON A. CUTHBERT I. D. CAMPBELL A. HERBERT J. M. THEAKER G. T. ROYLE I. TAYLOR 《Cytopathology》1993,4(5):257-266
Oestrogen receptor (ER) status of 77 cases of screen-detected breast cancer has been determined using cytological preparations. In 48% ER status was positive, which was the same proportion as that formed in a control group of age-matched patients with symptomatic breast carcinoma. Since the screen-detected group contained more low grade tumours, the percentage of ER-positive cases would be expected to be higher. the reasons for the discrepancy are discussed. Ki67 score has been determined for 41 cases of screen-detected cancer. Ki67 score showed a positive correlation with histological tumour grade and a negative correlation with ER status. However, there was no correlation with tumour size or lymph node status. the Ki67 scores in the screen-detected cancers were essentially similar to those found in an age-matched symptomatic group, but the very low scores were only found in the screened group. 相似文献
14.
François-Yves Dupradeau Guillaume Le Flem Jean-Michel Wieruszeski Manuel Dauchez Alain Alix Véronique Larreta-Garde Jean-Pierre Monti 《Letters in Peptide Science》1997,4(4-6):489-495
H-NMR studies of the bovine insulin S-sulfonatedB-chain are reported in H2O/D2O (9/1) and inglycerol-d5 (5 M) using two-dimensional NMRspectroscopy. The first results show that the oxidizedinsulin B-chain secondary structure differs from thatof native insulin by a loss of the -helixbetween the two disulfide bridges and that theglycerol favours the structuring of the peptide. 相似文献
15.
Endocrine cell cultures have potential in bioprocessing, for the production of biologically active hormones, and in tissue engineering, for the development of implantable artificial tissues for long-term restoration of endocrine function. To optimize such systems, it is necessary to develop a thorough understanding of how inherently present environmental stresses, such as nutrient depletion and metabolite accumulation, affect the cells. This work focuses on the effects of the metabolite ammonium on indicators of endocrine cell metabolism and on the processing, storage and secretion of regulated secretory proteins. Experiments were conducted on recombinant insulin-producing mouse pituitary AtT-20 cells and mouse insulinoma TC3 cells. Exposure for 24–48 hours to 6 mM of exogenous ammonium resulted in higher rates of glucose consumption by both AtT-20 and TC3 cells, while the formation of additional ammonium generally decreased relative to ammonium-free controls. When TC3 cells were discharged of their intracellular insulin stores, the presence of ammonium during a subsequent recharge completely inhibited addition of new insulin-related peptides to the stores, as we had observed previously for both cell lines. There was a correlation between insulin-related peptides stored in TC3 cells during recharging and the amount that could be released upon secretagogue stimulation. Using a combination of radioimmunoassay and high performance liquid chromatography, we found that intracellular insulin and insulin-related peptides changed in the same fashion. Intracellular mechanisms that may be producing the observed results are discussed.Abbreviations IRP
insulin-related peptides
- HPLC
high performance liquid chromatography
- DAMP
3-(2,4-dinitroanilino)-3 amino-N-methyldipropylamine 相似文献
16.
Meiheng Yang Howard Allen Hisao Fukushima Richard A. DiCioccio 《Glycoconjugate journal》1984,1(1):15-19
Fucosidosis is an autosomal recessive lysosomal storage disease resulting from the absence of -l-fucosidase activity. Two natural missense mutations (G197A) and (A860G) within the -l-fucosidase gene have been reported to be homozygous in four patients with fucosidosis. Expression of wild-type and mutated -l-fucosidase cDNAs in COS-1 cells revealed complete deficiency of -l-fucosidase for the G197A transition and a normal level of enzyme for A860G. We therefore conclude that the change of G197A is responsible for fucosidosis in the patients while A860G is a normal polymorphic variant of -l-fucosidase. 相似文献
17.
Gabriel J. FuenteGmez Creighton L. Kellum Alexis C. Miranda Michael R. Duff Jr Elizabeth E. Howell 《Protein science : a publication of the Protein Society》2021,30(2):477
R67 dihydrofolate reductase (R67 DHFR) is a plasmid‐encoded enzyme that confers resistance to the antibacterial drug trimethoprim. R67 DHFR is a tetramer with a single active site that is unusual as both cofactor and substrate are recognized by symmetry‐related residues. Such promiscuity has limited our previous efforts to differentiate ligand binding by NMR. To address this problem, we incorporated fluorine at positions 4, 5, 6, or 7 of the indole rings of tryptophans 38 and 45 and characterized the spectra to determine which probe was optimal for studying ligand binding. Two resonances were observed for all apo proteins. Unexpectedly, the W45 resonance appeared broad, and truncation of the disordered N‐termini resulted in the appearance of one sharp W45 resonance. These results are consistent with interaction of the N‐terminus with W45. Binding of the cofactor broadened W38 for all fluorine probes, whereas substrate, dihydrofolate, binding resulted in the appearance of three new resonances for 4‐ and 5‐fluoroindole labeled protein and severe line broadening for 6‐ and 7‐fluoroindole R67 DHFR. W45 became slightly broader upon ligand binding. With only two peaks in the 19F NMR spectra, our data were able to differentiate cofactor and substrate binding to the single, symmetric active site of R67 DHFR and yield binding affinities. 相似文献
18.
G Gashi V Mahovlić E Bahtiri F Kurshumliu A Podrimaj-Bytyqi IR Elezaj 《Biotechnic & histochemistry》2013,88(7):496-504
Human papilloma virus (HPV) infection is the main etiological factor for cervical intraepithelial lesions (CIN). An important characteristic of this process is the loss of genome stability. Therefore, it is imperative to use biomarkers of DNA damage caused by genomic instability to identify high risk individuals. We investigated the frequency of micronuclei (MN) in peripheral blood lymphocytes (PBL) of 20 patients, diagnosed as histologically CIN 1 and 10 healthy controls. We also examined the frequency of other nuclear anomalies including nucleoplasmic bridges (NPBs) and nuclear buds (NBUDs) in PBL of patients with CIN 1 and healthy controls, and evaluated the benefits of p16INK4a and Ki-67 (p16INK4a/Ki-67) immunohistochemical double staining for identifying cervical squamous cells that express HPV E6/E7 oncogenes. We analyzed the association between the frequency of MN in PBL and the amount of p16INK4a/Ki-67 co-expression in CIN 1 patients to establish genomic instability. Among CIN 1 subjects, 15% exhibited diffuse p16INK4a/Ki-67 co-expression and were considered high positive, 25% of the CIN 1 cases exhibited p16INK4a/Ki-67 co-expression restricted to the lower part of the epithelium and were considered low positive and the remaining 60% of cases were negative. The frequency of MN, NPBs and NBUDs differed significantly among groups. We found a statistically significant positive correlation between p16INK4a/Ki-67 co-expression and the frequency of MN, NPBs and NBUDs in PBL. Our findings demonstrate the efficacy of p16INK4a/Ki-67 double immunostaining for histological samples with CIN 1. MN frequency in PBL might be useful for detecting genomic instability in cases of HPV infection and CIN. 相似文献
19.
《Biotechnic & histochemistry》2013,88(5):223-247
AbstractIt is accepted that aldehyde-based fixation of cells can affect immunodetection of antigens; however, the effects of tissue processing on immunodetection have not been analyzed systematically. We investigated the effects of aldehyde-based fixation and the various cumulative steps of tissue processing on immunohistochemical detection of specific antigens. DU145 (prostate) and SKOV3 (ovarian) cancer cell lines were cultured as monolayers on microscope slides. Immunohistochemical detection of Ki67/MIB-1 and proliferating cell nuclear antigen (PCNA) was evaluated after various fixation times in 10% neutral buffered formalin and after each of the several cumulative steps of tissue processing. The effect of antigen retrieval (AR) was evaluated concomitantly as an additional variable. Our results indicate that in addition to fixation, each of the tissue processing steps has effects on immunorecognition of the epitopes recognized by these antibodies. Extensive dehydration through ethanols to absolute ethanol had only modest effects, except for the detection of Ki67/MIB-1 in SKOV-3 cells where the effect was stronger. In general, however, establishment of a hydrophobic environment by xylene resulted in the greatest decrease in immunorecognition. AR compensated for most, but not all, of the losses in staining following fixation and exposure to xylene; however, AR gave consistent results for most steps of tissue processing, which suggests that AR also should be used for staining PCNA. The cellular variations that were observed indicate that the effects of fixation and other steps of tissue processing may depend on how antigens are packaged by specific cells. 相似文献
20.
A. Calascibetta D. Cabibi L. Rausa F. Aragona E. Barresi A. Martorana 《Nucleosides, nucleotides & nucleic acids》2013,32(9-11):1193-1196
Breast cancer is a heterogeneous disease, so therapeutic predictive biological markers need to be identified. To date an accurate evaluation of predictive markers is mainly done at the primary site; however, the main goal of adjuvant therapy for breast cancer is the control of micrometastases. The aim of this study is to assess as therapeutic and/or prognostic marker, the proliferation status of primary tumors and involved nodes as measured by Ki67 and thymidylate synthase (TS) expression, in 30 breast cancer node positive patients. TS is the main target of 5-fluorouracil (5-FU) activity, and its overexpression is one of the mechanisms of 5-FU drug resistance; however, in some studies its absence is responsible for a worse response to 5-FU. Our results show that malignant cells of involved nodes were in a post mitotic phase of the cell cycle, and show a low proliferation index and TS expression, while the primary tumours and controls, were strongly positive. On these basis we can hypothesize that these cells could be less sensitive to 5-FU. Further studies are necessary to identify other mechanisms responsible for their metastasing capability and/or for their aggressiveness. 相似文献