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61.
Effect of n-3 and n-6 fatty acids on proliferation and differentiation of promyelocytic leukemic HL-60 cells 总被引:9,自引:0,他引:9
Finstad HS; Kolset SO; Holme JA; Wiger R; Farrants AK; Blomhoff R; Drevon CA 《Blood》1994,84(11):3799-3809
Promyelocytic leukemic HL-60 cells were incubated with different fatty acids. Arachidonic acid (AA; 20:4, n-6) and eicosapentaenoic acid (EPA; 20:5, n-3) were the most potent inhibitors of proliferation in a dose- dependent way. Retinoic acid (RA) was used as a positive control. Inhibitors of cyclooxygenase and lipoxygenase or addition of antioxidants did not influence the effect of EPA or AA on cell proliferation. Increased capacity to generate superoxide anions after phorbol ester treatment and a reduced serglycin messenger RNA level in cells treated with AA or EPA indicated that these fatty acids induced differentiation in HL-60 cells similar to that induced by RA. However, down-regulation of the c-myc mRNA level, also typical for differentiation with RA in HL-60 cells, was not observed in cells incubated with AA or EPA. Flow cytometric analyses showed that in cultures incubated with AA or EPA, the proportion of cells in the G1 phase of the cell cycle increased. Similar effects were observed with RA. By flow cytometry and light scatter analyses it could be shown that AA made 8% of the cells apoptotic and 7% necrotic. The corresponding numbers were 21% and 10% for RA-treated cells, and 19% and 32% for EPA- treated cells. The present study shows that AA and EPA reduce the proliferation rate of HL-60 cells. This is mediated by mechanisms independent of eicosanoids or lipid peroxidation products and is due to effects both on apoptosis/necrosis and cell differentiation. 相似文献
62.
Diarrhoea and weight loss are frequently reported adverse events in rheumatoid arthritis (RA) patients receiving the disease-modifying antirheumatic drug (DMARD) leflunomide. According to the available literature these side effects occur mostly during the first 6 months of treatment, are rather mild and rarely lead to treatment withdrawal. In this report, we describe the clinical, endoscopic and histologic findings in two RA patients with severe diarrhoea and important weight loss more than 12 months after starting treatment with leflunomide. In both cases the symptoms were caused by colitis, but one had ulcerative and the other microscopic colitis. Despite treatment with budesonide the complaints only improved after withdrawal of leflunomide, making a causal relationship between this drug and the pathogenesis of colitis probable. The heterogeneous histopathological findings in these two patients, however, do not allow us to draw any definitive conclusions about the mechanism by which leflunomide causes diarrhoea and weight loss in RA patients. We conclude that persistent diarrhoea or weight loss in patients taking leflunomide can be more serious than what is previously reported in the literature. In such cases leflunomide treatment should be stopped and an endoscopic examination of the colon is recommended. Given the long half-life of this drug a washout procedure with cholestyramine should be considered whenever the problem is severe or persistent. 相似文献
63.
Arrhythmogenic Evidence for Epicardial Adipose Tissue: Heart Rate Variability and Turbulence are Influenced by Epicardial Fat Thickness
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64.
65.
Older Adults and Unanticipated Hospital Admission within 30 Days of Ambulatory Surgery: An Analysis of 53,667 Ambulatory Surgical Procedures
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66.
67.
Jennifer VanderWeele Teresa Pollack Diana Johnson Oakes Colleen Smyrniotis Vidhya Illuri Priyathama Vellanki Kevin OLeary Jane Holl Grazia Aleppo Mark E. Molitch Amisha Wallia 《Journal of diabetes and its complications》2018,32(7):650-654
Aims
This study validated enterprise data warehouse (EDW) data for a cohort of hospitalized patients with a primary diagnosis of diabetic ketoacidosis (DKA).Methods
247 patients with 319 admissions for DKA (ICD-9 code 250.12, 250.13, or 250.xx with biochemical criteria for DKA) were admitted to Northwestern Memorial Hospital from 1/1/2010 to 9/1/2013. Validation was performed by electronic medical record (EMR) review of 10% of admissions (N?=?32). Classification of diabetes type (Type 1 vs. Type 2) and DKA clinical status were compared between the EMR review and EDW data.Results
Key findings included incorrect classification of diabetes type in 5 of 32 (16%) admissions and indeterminable classification in 5 admissions. DKA was not present, based on the review, in 11 of 32 (34%) admissions. DKA was not present, based on biochemical criteria, in 15 of 32 (47%) admissions.Conclusions
This study found that EDW data have substantial errors. Some discrepancies can be addressed by refining the EDW query code, while others, related to diabetes classification and DKA diagnosis, cannot be corrected without improving clinical coding accuracy, consistency of medical record documentation, or EMR design. These results support the need for comprehensive validation of data for complex clinical populations obtained through data repositories such as the EDW. 相似文献68.
Stable intrachain and interchain complexes of neurofilament peptides: a putative link between Al3+ and Alzheimer disease.
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M Hollósi Z M Shen A Perczel G D Fasman 《Proceedings of the National Academy of Sciences of the United States of America》1994,91(11):4902-4906
The etiologic role of Al3+ in Alzheimer disease has been controversial. Circular dichroism (CD) spectroscopic studies on two synthetic fragments of human neurofilament protein mid-sized subunit (NF-M), NF-M13 (KSPVPKSPVEEKG) and NF-M17 (EEKGKSPVPKSPVEEKG), and their alanine-substituted and/or serine-phosphorylated derivatives were carried out in an attempt to find a molecular mechanism for the effect of Al3+ to induce aggregation of neuronal proteins or their catabolic fragments. Al3+ and Ca2+ ions were found to induce beta-pleated sheet formation in the phosphorylated fragments. The cation sensitivity depended on the length and charge distribution of the sequence and site of phosphorylation. Al3+-induced conformational changes were irreversible to citric acid chelation, whereas Ca(2+)-induced conformational changes were reversible with citric acid. Studies of the alanine derivatives demonstrated which residues affected Al3+ or Ca2+ binding. Peptides containing at least one free (nonphosphorylated) serine residue were shown to form an intramolecular Al3+ complex, rather than an intermolecular one. In the intramolecular (intrachain) complex, the ligand function of the deprotonated serine hydroxyl was delineated [(Al.pepH-1)-type complex]. Ca2+ ions did not show a tendency for intramolecular complexing. The potential role of Al3+ in Alzheimer disease tangle and plaque formation is strongly suggested. 相似文献
69.
Daily insulin doses and injection frequencies of neutral protamine hagedorn (NPH) insulin,insulin detemir and insulin glargine in type 1 and type 2 diabetes: a multicenter analysis of 51 964 patients from the German/Austrian DPV‐wiss database
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70.
Ashley E. Davis Sanjay Mehrotra Vikram Kilambi Joseph Kang Lisa McElroy Brittany Lapin Jane Holl Michael Abecassis John J. Friedewald Daniela P. Ladner 《Clinical journal of the American Society of Nephrology》2014,9(8):1449-1460