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Amplified C lambda and c-abl genes are on the same marker chromosome in K562 leukemia cells. 总被引:16,自引:6,他引:16 下载免费PDF全文
J R Selden B S Emanuel E Wang L Cannizzaro A Palumbo J Erikson P C Nowell G Rovera C M Croce 《Proceedings of the National Academy of Sciences of the United States of America》1983,80(23):7289-7292
The human leukemia cell line K562, derived from a patient with Philadelphia chromosome-positive chronic myelogenous leukemia, contains amplified c-abl oncogenes and unrearranged C lambda genes. Using in situ hybridization techniques, we have determined that the amplified c-abl and C lambda DNA sequences of K562 cells are both located on the same abnormal acrocentric marker chromosome, which may represent an altered Philadelphia chromosome. 相似文献
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Characterization and Substrate Specificity of a Protein Carboxymethylase in the Pituitary Gland 总被引:9,自引:3,他引:9 下载免费PDF全文
Emanuel J. Diliberto Jr. Julius Axelrod 《Proceedings of the National Academy of Sciences of the United States of America》1974,71(5):1701-1704
Protein carboxymethylase, an enzyme capable of methylating proteins and polypeptides, was purified from bovine pituitary. The anterior pituitary hormones, luteinizing hormone, follicle-stimulating hormone, adrenocorticotropic hormone, growth hormone, thyroid-stimulating hormone, and prolactin, were found to be substrates for this enzyme. The posterior pituitary hormones, oxytocin and vasopressin, did not serve as substrates. With luteinizing hormone as the substrate, protein carboxymethylase had a pH optimum near pH 5.5. A limiting K(m) of 1.47 muM for S-adenosyl-L-methionine was obtained with luteinizing hormone as the methyl acceptor. Possible roles of this enzyme in the posterior and anterior pituitary are discussed. 相似文献
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Assimakopoulos SF Thomopoulos KC Louvros E Theocharis G Giannikoulis C Katsakoulis E Nikolopoulou VN 《The American journal of the medical sciences》2008,336(1):21-26
BACKGROUND: During the past years, major advances in the management of upper gastrointestinal diseases have been achieved. The aim of this study was to determine if changes in indications for upper gastrointestinal endoscopy and endoscopic findings have occurred during the last 15 years in our area. METHODS: Indications for upper gastrointestinal tract endoscopy and endoscopy findings of patients who underwent upper endoscopy in years 1990, 1995, 2000, and 2005 in our department were compared. RESULTS: Over the 15-year period, the number of diagnostic endoscopies performed in our department in years 1990, 1995, 2000, and 2005 increased (953, 1245, 2350, and 2528, respectively). Acute upper gastrointestinal bleeding had become less frequent (40%, 42.8%, 19.7%, 14.3%, P<0.001), but dyspepsia (24.4%, 33.6%, 54.3%, 51.3%, P=0.002) and reflux (1.8%, 1.3%, 5.1%, 10.8%, P=0.005) more frequent indications for upper endoscopy. The endoscopic findings of duodenal ulcer (39.1%, 22.5%, 20.5%, 9.3%, P<0.001), gastric ulcer (15.9%, 8.3%, 5.7%, 4.6%, P=0.036) as well as erosive gastroduodenitis (35.6%, 22.2%, 15.3%, 4.7%, P<0.001) decreased, whereas that of reflux esophagitis (3.1%, 10.1%, 12%, 16%, P=0.034) increased. Moreover, the percentage of patients with negative endoscopy or minimal endoscopic findings (eg, nonerosive gastritis) increased (12.8%, 33.7%, 54.1%, 64.4%, P<0.001). CONCLUSIONS: In south-western Greece, dyspepsia and reflux as an indication for upper endoscopy have been increasing, whereas acute upper gastrointestinal bleeding has been decreasing. The finding of peptic ulcers at the upper gastrointestinal tract endoscopy has become significantly less frequent, while the percentage of patients with negative results of endoscopy seems to have been increasing rapidly. 相似文献
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Recent preclinical and clinical trials have demonstrated the therapeutic potential of T lymphocytes redirected with genetically engineered T-cell receptor (TCR) surrogates against infected, cancerous, or autoreactive cells. These surrogate TCRs link a ligand-recognition domain to signaling regions from the TCR. We previously compared the function of surrogate TCRs that include TCR or TCR and CD28 signaling regions. We found that primary murine T cells modified to specifically target Kb-restricted CD8+ T cells using either Kb-zeta or Kb-CD28-zeta receptors had similar functional activities, although the CD28-zeta receptor showed a 2-fold to 4-fold decreased expression. We have now identified a previously unrecognized dileucine motif in the murine CD28 signaling domain that accounts for this reduced expression. Inactivation of this motif increased chimeric receptor surface expression 2- to 5-fold. T cells expressing the dileucine-mutated CD28-zeta chimeric receptor demonstrated enhanced proliferation, cytokine production, and cytolytic activities. Further, cells expressing this dileucine-mutated receptor were highly effective in eliminating antigen-specific CD8+ T lymphocytes in vivo. These results therefore identify a critical motif limiting the function of receptor-modified T lymphocytes, demonstrate that inactivation of this motif enhances chimeric receptor function, and illustrate a potential novel application of receptor-modified T lymphocytes in the induction of immune tolerance. 相似文献
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Emanuel Raschi Igor Diemberger Benilde Cosmi Fabrizio De Ponti 《Internal and emergency medicine》2018,13(1):1-9
The recent position paper of the European Society of Cardiology (ESC) on cardiovascular toxicity of cancer treatments has attracted considerable interest by healthcare professionals, since it is the first concrete help in the difficult task of monitoring and approaching cardiovascular side effects of anticancer treatments. The ESC expert opinion was not intended as a clinical practice guideline; however, it reports major cardiovascular complications grouped into nine categories, addressing current clinical strategies for prevention and mitigation. In this point of view, we discuss key challenges emerging from critical appraisal of the ESC position paper: (1) the wide spectrum of cardiovascular toxicities associated with oncological drugs, focusing on targeted agents, (2) managing strategies in patients with cardiac implantable devices, (3) the underappreciated (but emerging) immune-related cardiovascular toxicities of checkpoint inhibitors, which may also result in severe heart failure and fulminant myocarditis, (4) the evolving role of anticoagulation in oncology, and the evidence supporting (or not) the use of direct-acting oral anticoagulants in cancer-associated thrombosis. 相似文献
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Meng Niu Brenda Morsey Benjamin G. Lamberty Katy Emanuel Fang Yu Rosiris Len-Rivera Joan W. Berman Peter J. Gaskill Stephanie M. Matt Pawel S. Ciborowski Howard S. Fox 《Viruses》2020,12(11)
Both substance use disorder and HIV infection continue to affect many individuals. Both have untoward effects on the brain, and the two conditions often co-exist. In the brain, macrophages and microglia are infectable by HIV, and these cells are also targets for the effects of drugs of abuse, such as the psychostimulant methamphetamine. To determine the interaction of HIV and methamphetamine, we isolated microglia and brain macrophages from SIV-infected rhesus monkeys that were treated with or without methamphetamine. Cells were subjected to single-cell RNA sequencing and results were analyzed by statistical and bioinformatic analysis. In the animals treated with methamphetamine, a significantly increased proportion of the microglia and/or macrophages were infected by SIV. In addition, gene encoding functions in cell death pathways were increased, and the brain-derived neurotropic factor pathway was inhibited. The gene expression patterns in infected cells did not cluster separately from uninfected cells, but clusters comprised of microglia and/or macrophages from methamphetamine-treated animals differed in neuroinflammatory and metabolic pathways from those comprised of cells from untreated animals. Methamphetamine increases CNS infection by SIV and has adverse effects on both infected and uninfected microglia and brain macrophages, highlighting the dual and interacting harms of HIV infection and drug abuse on the brain. 相似文献
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