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91.
Marjan Boerma Gregory R Burton Junru Wang Louis M Fink Robert E McGehee Martin Hauer-Jensen 《Blood coagulation & fibrinolysis》2006,17(3):173-180
Immortalized cell lines offer significant logistical advantages over primary cells when used for in-vitro studies. Immortalized cells may, however, exhibit important differences relative to their primary cell counterparts. In this study, microarrays were used to make a genome-wide comparison between primary human umbilical vein endothelial cells (HUVECs) and EA.hy926, an immortalized HUVEC cell line, in their baseline properties and in their response to inhibition of the mevalonate pathway with an inhibitor of hydroxy methylglutaryl-coenzyme A reductase (statin). HUVECs and EA.hy926 were incubated with control medium, atorvastatin, mevalonate, or a combination of atorvastatin and mevalonate for 24 h. Gene expression profiles were obtained in duplicates using Affymetrix Human Genome U133A 2.0 arrays (Santa Clara, California, USA). Probe-sets were selected according to the following criteria: a twofold or greater increase/decrease in atorvastatin-treated cells compared with untreated cells; a twofold or greater reversal of the effect of atorvastatin by combined treatment with atorvastatin and mevalonate; no significant change in gene expression in cells treated with mevalonate alone compared with untreated cells. Most genes that were expressed by untreated HUVECs, were also expressed by untreated EA.hy926 cells. EA.hy926 cells, however, constitutively expressed a large number of additional genes, many of which were related to cell cycle control and apoptosis. Atorvastatin induced differential expression (> or = twofold) of 103 genes in HUVECs (10 up, 93 down) and 466 genes in EA.hy926 cells (198 up, 268 down). Applying the above selection criteria, thrombomodulin and tissue plasminogen activator were up-regulated in both cell types, whereas, connective tissue growth factor, thrombospondin-1, and cysteine-rich angiogenic inducer 61 were down-regulated. In conclusion, EA.hy926 cells retain most of the characteristics of endothelial cells under baseline conditions as well as after treatment with atorvastatin. It is necessary, however, to carefully select and validate changes in genes that are the focus of studies when using EA.hy926 cells. While this cell line is highly useful in studies on some genes, including genes encoding molecules involved in regulating thrombohemorrhagic homeostasis, they appear to be less suited for studies focused on other genes, particularly those involved in the regulation of cell proliferation and apoptosis. 相似文献
92.
Nicholas Kipshidze Martin B Leon 《Journal of the American College of Cardiology》2006,47(9):1911; author reply 1912-1911; author reply 1913
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Martin A Ritter Achim Frese Rainer Dziewas Stefan Knecht Stefan Evers 《Movement disorders》2006,21(10):1787-1788
Synkinesias secondary to nerve lesions and aberrant re-innervation are well-known phenomena especially after lesions of the facial nerve. Synkinesias can successfully be treated with botulinum toxin A (BTx A). Synkinesias of the cremaster muscle have not been described or treated to date. We present the case of a 62-year-old man who developed synkinesias of both cremaster muscles after extensive laparatomy for esophageal cancer. Treatment of synkinesias with various oral medications had been unsuccessful. Electromyography-guided injections of BTx A in both cremaster muscles (15 MU on the right and 10 on the left) led to significant symptom relief for an average of 8 weeks. We present the case including pre- and posttreatment video clips. 相似文献
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A 73-year-old woman was studied after admission for anteriorwall ST-segment elevation myocardial infarction. Transthoracicechocardiography (GE Vingmed, Vivid 7, Horten, Norway) 相似文献
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AIMS: To determine the morbidity, mortality and healthcare costs of intravenous drug-abusing patients with Type 1 diabetes (IVDA-DM), who are admitted to hospital. METHODS: Retrospective case note analysis of admissions, complications and cost estimation over a 6-year period. Each drug-abusing patient (IVDA-DM) (n = 9) was compared with two controls (n = 18) with Type 1 diabetes but without a history of intravenous drug abuse (DM-controls). Admissions were also analysed for patients with intravenous drug abuse, but without Type 1 diabetes (IVDA-controls) (n = 198). Admissions were at a University teaching hospital in Liverpool, UK. DM-controls were drawn from a population attending diabetes outpatient clinics between 1997 and 2002 at the same hospital. The main outcome measures were: the duration and healthcare costs of hospital admissions per year, outpatient attendances per year, glycated haemoglobin (HbA(1c)), weight, micro- and macrovascular complications and mortality. RESULTS: Multiple admissions, mainly related to ketoacidosis, led to marked differences in mean (95% CI) inpatient days per year per patient [IVDA-DM 28.1 (13.6-42.7) vs. DM-control 1.1 (0.2-1.9); P < 0.0001], mean inpatient days per year per patient in critical care bed (IVDA-DM 1.7 (-0.7-4.2) vs. DM-control 0; P < 0.02) and mean costs of admission, per patient per year (pound sterling 7320 vs. pound sterling 230). The IVDA-DM group frequently omitted insulin, were underweight, failed to attend as outpatients and five had died by the end of 2002. The IVDA-controls spent considerably less time in hospital [3.4 (2.8-3.9) days per patient per year]. CONCLUSION: IVDA-DM patients have higher rates of diabetes complications, are admitted more frequently and have a high mortality compared with DM and IVDA-controls. The cost of inpatient care of this small group of patients was considerable. 相似文献