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951.
Elevated telomerase activity and minimal telomere loss in cord blood long-term cultures with extensive stem cell replication 总被引:2,自引:0,他引:2 下载免费PDF全文
Gammaitoni L Weisel KC Gunetti M Wu KD Bruno S Pinelli S Bonati A Aglietta M Moore MA Piacibello W 《Blood》2004,103(12):4440-4448
Telomerase activity, telomere length, stem/progenitor cell production, and function of CD34+ cells from cord blood (CB), bone marrow, and mobilized peripheral blood were evaluated in long-term cultures. CB cells were cultured either on OP-9 stromal cells transduced with an adenovector expressing thrombopoietin (TPO) or stimulated by a cytokine cocktail in the absence of stroma, with, in one method, CD34+ cells reisolated at monthly intervals for passage. Continuous expansion of stem cells as measured by in vitro cobblestone area and secondary colony-forming assays was noted for 18 to 20 weeks and by severe combined immunodeficiency (SCID)-repopulating cells (SRCs), capable of repopulating and serially passage in nonobese diabetic/SCID mice, for 16 weeks. Despite this extensive proliferation, telomere length initially increased and only at late stages of culture was evidence of telomere shortening noted. This telomere stabilization correlated with maintenance of high levels of telomerase activity in the CD34+ cell population for prolonged periods of culture. Cytokine-stimulated cultures of adult CD34+ cells showed CD34+ and SRC expansion (6-fold) for only 3 to 4 weeks with telomere shortening and low levels of telomerase. There is clearly a clinical value for a system that provides extensive stem cell expansion without concomitant telomere erosion. 相似文献
952.
Tumor M2-Pyruvate Kinase, a New Metabolic Marker for Pancreatic Cancer 总被引:16,自引:0,他引:16
Ventrucci M Cipolla A Racchini C Casadei R Simoni P Gullo L 《Digestive diseases and sciences》2004,49(7-8):1149-1155
An isoenzyme of pyruvate kinase (Tu M2-PK) is overexpressed by tumor cells and can be measured in blood by a specific immunoenzymatic assay. Our objective was to investigate the diagnostic value of Tu M2-PK in comparison with that of CA 19-9 in pancreatic cancer. We studied 265 subjects: 60 with histologically confirmed pancreatic cancer, 43 with benign pancreatic diseases (acute and chronic pancreatitis), 5 with benign cystic neoplasms of the pancreas, 9 with neuroendocrine tumors, 77 with other abdominal malignancies, 47 with benign digestive diseases, and 24 healthy controls. Levels of plasma Tu M2-PK and serum CA 19-9 were determined by commercially available specific immunoassays. The diagnostic sensitivity and specificity of Tu M2-PK for pancreatic cancer were 85 and 41%, respectively, while those of CA 19-9 were 75 and 81%. The combination of the two tests significantly increased sensitivity (97%) but lowered specificity (38%). In discriminating between pancreatic cancer and acute or chronic pancreatitis, Tu M2-PK turned out to be less accurate than CA 19-9. In patients without pancreatic tumor, cholestasis appeared not to affect the values of Tu M2-PK, while CA 19-9 was found to be significantly higher. Tu M2-PK was also abnormally high in the majority of patients with other digestive malignancies or neuroendocrine tumors. The results demonstrate that Tu M2-PK has a satisfactory sensitivity but a poor specificity in the diagnosis of pancreatic cancer. Used together with CA 19-9, the sensitivity increases considerably. 相似文献
953.
Moroi Masaaki; Jung Stephanie M.; Nomura Shosaku; Sekiguchi Sadayoshi; Ordinas Antonio; Diaz-Ricart Maribel 《Blood》1997,90(11):4413-4424
954.
Michele Di Mauro Angela L Iacò Marco Contini Giuseppe Vitolla Luca Weltert Gabriele Di Giammarco Antonio M Calafiore 《Italian heart journal》2005,6(5):390-395
BACKGROUND: We evaluated the early and late outcomes of bilateral internal mammary artery (BIMA) grafting, with or without saphenous vein grafts (SVGs), compared to single internal mammary artery and SVGs in patients < 70 years undergoing first myocardial revascularization. METHODS: From September 1986 to December 1999, 1389 patients underwent first myocardial revascularization using the left internal mammary artery (LIMA) to the left anterior descending artery and SVGs (n = 480) or BIMA (one internal mammary artery on the left anterior descending artery) with or without SVGs (n = 909). Propensity score analysis was used to select 952 (476 of each group) patients with the same preoperative and operative characteristics. Thirty-day outcome and 10-year freedom from all-cause death, cardiac death, acute myocardial infarction (AMI), AMI in a grafted area, redo/percutaneous transluminal coronary angioplasty (PTCA), redo/PTCA in a grafted artery, cardiac events and any events, were evaluated. Follow-up ranged from 3.5 to 16.8 years (mean 8.8+/-4.0 years). RESULTS: Thirty-day mortality was 2.9% in the LIMA group and 1.9% in the BIMA group, p = NS; the BIMA group showed a better 10-year freedom from all-cause death (92.4+/-2.1 vs 87.5+/-3.5%, p = 0.0216), cardiac death (97.4+/-0.9 vs 91.9+/-1.4%, p = 0.0042), AMI (98.7+/-0.5 vs 94.2+/-1.2%, p = 0.0034), AMI in a grafted area (98.9+/-0.5 vs 94.7+/-1.3%, p = 0.0017), cardiac events (95.4+/-1.2 vs 86.8+/-1.8%, p = 0.0026) and any events (88.8+/-2.2 vs 80.7+/-2.1%, p = 0.0124). Cox analysis confirmed that LIMA + SVGs was a risk factor independent of lower freedom from all the above-mentioned events. CONCLUSIONS: Double mammary artery in patients < 70 years who had a first time myocardial revascularization gives a better clinical outcome even 10 years after the operation. 相似文献
955.
Cazals-Hatem D Rebouissou S Bioulac-Sage P Bluteau O Blanché H Franco D Monges G Belghiti J Sa Cunha A Laurent-Puig P Degott C Zucman-Rossi J 《Journal of hepatology》2004,41(2):292-298
BACKGROUND/AIMS: Combined hepatocellular-cholangiocarcinoma (HCC-CC) show dual hepatocellular and biliary epithelial differentiation. To better understand the relations between cholangiocarcinoma (CC), HCC-CC and hepatocellular carcinoma (HCC), we screened for genetic alterations. METHODS: A series of nine CC, 15 HCC-CC and three separated HCC and CC lesions ('collision tumors') were screened for loss of heterozygosity (LOH) using 400 microsatellite markers and for p53 and beta-catenin mutations. A comparison with a previously characterized series of 137 HCC was performed. RESULTS: In six cases of CC and HCC-CC, we identified TP53 gene mutations. A CTNNB1/beta-catenin was identified in two patients presenting collision tumors, but no mutations were found in CC or in HCC-CC. A high level of chromosome instability in both CC and HCC-CC was found. Recurrent specific LOH were identified at 3p and 14q in more than 50% of the CC and the HCC-CC cases, whereas these chromosomal regions were deleted in less than 10% of the HCC cases (P<10(-5)). Minimal common regions of deletion (MCRD) were defined at 3p24-p14 and 14q24-q32, respectively. CONCLUSIONS: These results suggest that combined HCC-CC are genetically closer to CC than HCC and common carcinogenesis pathways may be altered in HCC-CC and CC. 相似文献
956.
957.
Rhu-Epo down-regulates pro-tumorigenic activity of cancer-associated fibroblasts in multiple myeloma
Vanessa?Desantis Maria?Antonia?Frassanito Roberto?Tamma Ilaria?Saltarella Lucia?Di?Marzo Aurelia?Lamanuzzi Antonio?Giovanni?Solimando Simona?Ruggieri Tiziana?Annese Beatrice?Nico Angelo?Vacca Domenico?RibattiEmail authorView authors OrcID profile 《Annals of hematology》2018,97(7):1251-1258
We have previously demonstrated that recombinant human erythropoietin (rHuEpo) is involved in the regulation of the angiogenic response in multiple myeloma (MM) through a direct effect on macrophages and endothelial cells isolated from the bone marrow of patients with MM. The aim of the present study was designed to determine the effects of rHuEpo on cancer-associated fibroblasts (CAFs) from monoclonal gammopathy of undetermined significance (MGUS) and MM patients by means of in vitro and in vivo assays. rHuEpo treatment reduces the expression of mRNA levels of fibroblast activation markers, namely alpha smooth actin (αSMA) and fibroblast activation protein (FAP) in MGUS and MM CAFs, and of pro-inflammatory and pro-angiogenic cytokines, including interleukin (IL)-6 and IL-8, vascular endothelial growth factor-A (VEGF-A), fibroblast growth factor-2 (FGF-2), and hepatocyte growth factor (HGF) in MM CAFs. Moreover, rHuEpo inhibits the proliferative activity of MM CAFs and increased the apoptosis of MGUS and MM CAFs. Overall, these data suggest that rHu-Epo down-regulates CAFs pro-tumorigenic activity. Moreover, these results are not suggestive for a pro-angiogenic activity of rHuEpo on CAFs. In fact, rHuEpo pre-treatment induces a low angiogenic response in vivo in the chorioallantoic membrane (CAM) assay of MGUS and MM CAFs conditioned medium, not comparable to that of a well-known angiogenic cytokine, VEGF-A, tested in the same assay. 相似文献
958.
Neurological examination findings to predict limitations in mobility and falls in older persons without a history of neurological disease 总被引:2,自引:0,他引:2
Ferrucci L Bandinelli S Cavazzini C Lauretani F Corsi A Bartali B Cherubini A Launer L Guralnik JM 《The American journal of medicine》2004,116(12):807-815
PURPOSE: To estimate the prevalence of neurological signs and their association with limitations in mobility and falls in a sample of older persons without known neurological disease. METHODS: A neurologist examined 818 participants from the InCHIANTI study who were aged > or =65 years and who did not have cognitive impairment, treatment with neuroleptics, and a history of neurological disease. Mobility was assessed as walking speed and self-reported ability to walk at least 1 km without difficulty. Participants were asked to report falls that had occurred in the previous 12 months. RESULTS: Less than 20% (160/818) of participants had no neurological signs. Neurological signs were more prevalent in older participants and those with impaired mobility. When all neurological signs were included in sex-and age-adjusted multivariate models, 10 were mutually independent correlates of poor mobility. After adjusting for age and sex, the number of neurological signs was associated with progressively slower walking speed (P <0.001), a higher probability of reported inability to walk 1 km (P <0.001), and a history of falls (P <0.05). CONCLUSION: Neurological signs are independent correlates of limitations in mobility and falls in older persons who have no clear history of neurological disease. 相似文献
959.
De Berardis G Pellegrini F Franciosi M Belfiglio M Di Nardo B Greenfield S Kaplan SH Rossi MC Sacco M Tognoni G Valentini M Nicolucci A;QuED 《Nutrition, metabolism, and cardiovascular diseases : NMCD》2008,18(1):57-65
Background and aimIn the context of the QuED Study we assessed whether a quality of care summary score was able to predict the development of cardiovascular (CV) events in patients with type 2 diabetes.Methods and resultsThe score was calculated using process and intermediate outcome indicators (HbA1c, blood pressure, low-density lipoprotein cholesterol, microalbuminuria) and ranged from 0 to 40. Overall, 3235 patients were enrolled, of whom 492 developed a CV event after a median follow-up of 5 years. The incidence rate (per 1000 person-years) of CV events was 62.4 in patients with a score ≤10, 54.8 in those with a score between 15 and 20, and 39.8 in those with a score >20. In adjusted multilevel regression models, the risk to develop a CV event was 89% greater in patients with a score of ≤10 (rate ratio [RR] = 1.89; 95% confidence interval [CI] 1.43–2.50) and 43% higher in those with a score between 10 and 20 (RR = 1.43; 95% CI 1.14–1.79), as compared to those with a score >20. A difference between centers of 5 points in the mean quality score was associated with a difference of 16% in CV event risk (RR = 0.84; 95% CI 0.72–0.98).ConclusionOur study documented for the first time a close relationship between a score of quality of diabetes care and long-term outcomes. 相似文献
960.