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61.
Chlodwig Kirchhoff Peter Biberthaler Wolf E Mutschler Eugen Faist Marianne Jochum Siegfried Zedler 《Critical care (London, England)》2009,13(3):R88-11
Introduction
Severe tissue trauma results in a general inflammatory immune response (SIRS) representing an overall inflammatory reaction of the immune system. However, there is little known about the functional alterations of monocytes in the early posttraumatic phase, characterized by the battle of the individual with the initial trauma. 相似文献62.
63.
Dimitrova KR DeGroot KW Suyderhoud JP Pirovic EA Munro TJ Wieneke J Myers AK Kim YD 《Journal of cardiovascular pharmacology》2002,39(3):347-353
High levels of homocysteine (Hcy) accelerate endothelial cell damage by producing hydrogen peroxide (H(2)O(2)). We investigated whether 17-beta estradiol may prevent the accelerated rate of endothelial cell detachment and reduced cell viability in cultured endothelial cells challenged with Hcy. Cultured bovine aortic endothelial cells (BAEC) were incubated for 72-h with either vehicle (alcohol) or different concentrations of 17-beta estradiol (1 nM [1E2] and 10 nM [10E2]) before being challenged with 0.5 mM of Hcy. Cell viability and H(2)O(2) levels were evaluated at 30 min, 1-, 2-, 4-, 8-, and 24-h after adding Hcy. Cell suspensions were frozen in liquid nitrogen and used later for spectrophotometric measurement of intracellular glutathione (GSH) levels. Cell viability 24 h after Hcy administration was significantly lower in vehicle versus 1 nM and 10 nM 17-beta estradiol (44 +/- 5% vs. 70.66 +/- 4%, [p < 0.001] and 79 +/- 5% respectively, [p < 0.001]). H(2)O(2) levels were higher in vehicle (1 +/- 0.05 microM) compared with 1E2 and 10E2 (0.8 +/- 0.1 microM, p = 0.02 and 0.1 +/- 0.05 microM, respectively, p < 0.001), whereas GSH content was increased in 1E1 and 10E2 versus control (27.69 +/- 4.6 nM/10(6) cells and 43.49 +/- 5.5 nM/10(6) cells vs. 13.33 +/- 1.5 nM/10(6) cells, p < 0.001). Bovine aortic endothelial cells treatment with 17-beta estradiol (0, 1, and 10 nM) and 0.1 mmol buthionine sulfoximine, an inhibitor of gamma-glutamylcysteine synthase, abolished the beneficial effects of estradiol alone on cell viability, GSH content, and H2O2 generation. Estradiol prevents Hcy-induced endothelial cell injury by increasing the intracellular content of GSH. 相似文献
64.
Sphingosine 1-phosphate enhances spontaneous transmitter release at the frog neuromuscular junction 下载免费PDF全文
Intracellular recordings were made from isolated frog sciatic-sartorius nerve-muscle preparations, and the effects of sphingosine 1-phosphate (S1-P) on miniature endplate potentials (MEPPs) were studied. Extracellular application of S1-P (1 and 30 micro M) had no significant effects on the frequency and amplitude of MEPPs. Delivery into nerve terminals by liposomes containing 10(-5), 10(-4) or 10(-3) M S1-P was associated with a concentration-dependent increase in MEPP frequency of 37, 63 and 86%. The per cent of median MEPP amplitude was not significantly changed, but there was an increase in the number of 'giant' MEPPs. Pre-exposure of the preparations to S1-P 10(-5) but not 10(-8) M entrapped in liposomes for 15 min blocked the effects of subsequent superfusion of S1-P (10(-4) M)-filled liposomes on MEPP frequency. Thus, intracellular S1-P receptors seem to undergo 'desensitization' to higher concentrations of S1-P. The result provides the first evidence that S1-P acting intracellularly but not extracellularly enhances spontaneous transmitter release at the frog neuromuscular junction. 相似文献
65.
Egerer K Hertzer J Feist E Albrecht A Rudolph PE Dörner T Burmester GR 《Arthritis and rheumatism》2003,49(4):546-548
OBJECTIVES: To determine the usefulness of sE-selectin as a marker for early diagnosis and stratification of rheumatoid arthritis. METHODS: We investigated several markers of disease activity, including circulating adhesion molecules and other standard laboratory tests, in a 2-3 year followup analysis of patients with rheumatoid arthritis. RESULTS: The mean +/- SD levels of sE-selectin (91.68 +/- 31.8 ng/ml versus 49.83 +/- 14.76 ng/ml) and rheumatoid factor (375.7 +/- 394.4 U versus 44.66 +/- 37.63 U) were strongly elevated in severe (n = 15) versus mild (n = 7) courses of disease. Statistical calculation of mean and standard deviation revealed that sE-selectin represents a highly significant marker for the presence of persistent and aggressive disease over time, regardless of therapeutic intervention and observation time points (P = 0.0004). Notably, regression analysis identified constant values for all parameters analyzed and, therefore, a stable course of the disease could be predicted from the beginning. CONCLUSION: sE-selectin appears to be a powerful marker to predict the severity of rheumatoid arthritis. 相似文献
66.
67.
Loss of kinase activity in a patient with Wolcott-Rallison syndrome caused by a novel mutation in the EIF2AK3 gene 总被引:3,自引:0,他引:3
Wolcott-Rallison syndrome (WRS) is an autosomal recessive disorder characterized by neonatal or early infancy type 1 diabetes, epiphyseal dysplasia, and growth retardation. Mutations in the EIF2AK3 gene, encoding the eukaryotic initiation factor 2alpha-kinase 3 (EIF2AK3), have been found in WRS patients. Here we describe a girl who came to our attention at 2 months of age with severe hypertonic dehydration and diabetic ketoacidosis. A diagnosis of type 1 diabetes was made and insulin treatment initiated. Growth retardation and microcephaly were also present. Anti-islet cell autoantibodies were negative, and mitochondrial diabetes was excluded. Imaging revealed a hypoplastic pancreas and typical signs of spondylo-epiphyseal dysplasia. The diagnosis of WRS was therefore made at age 5 years. Sequencing analysis of her EIF2AK3 gene revealed the presence of a homozygous T to C exchange in exon 13 leading to the missense serine 877 proline mutation. The mutated kinase, although it partly retains the ability of autophosphorylation, is unable to phosphorylate its natural substrate, eukaryotic initiation factor 2alpha (eIF2alpha). This is the first case in which the pathophysiological role of EIF2AK3 deficiency in WRS is confirmed at the molecular level. Our data demonstrate that EIF2AK3 kinase activity is essential for pancreas islet function and bone development in humans, and we suggest EIF2AK3 as a possible target for therapeutic intervention in diabetes. 相似文献
68.
Trinka E Unterberger I Spiegel M Niedermüller U Benke T Berger T Bauer G 《Journal of neurology》2002,249(6):782-783
Journal of Neurology - 相似文献
69.
70.
H. Oettle M. Arning U. Pelzer D. Arnold C. Stroszczynski J. Langrehr P. Reitzig M. Kindler J. Herrenberger R. Musch F. W. Korsten D. Huhn H. Riess 《Annals of oncology》2000,11(10):1267-1272
Background:Gemcitabine (Gemzar®) and 5-fluorouracil (5-FU)plus folinic acid (FA) both have proven activity in the treatment of patientswith advanced pancreatic cancer. The present study was initiated toinvestigate the efficacy of gemcitabine in combination with 5-FU–FA.
Patients and methods:Thirty-eight patients, median age 60 years(range 34–70) with inoperable, stage IV, pancreatic cancer were enrolledinto the study and treated on an outpatient basis. All except one patientreceived at least one cycle of treatment with gemcitabine (1000mg/m2), followed by FA (200 mg/m2) and 5-FU (750mg/m2) administered as a 24-hour continuous infusion on days 1, 8,15 and 22 of a 42-day schedule. No patient had received prior chemotherapy orradiotherapy. All 38 patients were assessed for efficacy, toxicity and timeto progressive disease.
Results:Two patients (5%), achieved a partial response andthirty-four patients (89%) achieved stable disease. There were twoearly deaths (4 weeks). The median time to progression was 7.1 months(range 0.4–18.1+; 95% confidence interval (95% CI):5.3–7.9 months). Three patients had a progression-free interval ofgreater than 12 months and 12 of 38 patients (32%) survived longer than12 months. The median overall survival was 9.3 months (range 0.5–26.5;95% CI: 7.3–13.0 months). The incidence of grade 3 and 4toxicities was low.
Conclusions:The combination of gemcitabine and 5-FU–FA isactive and well tolerated and seems to offer an improvement inprogression-free interval over both gemcitabine monotherapy and 5-FU–FAtherapy. 相似文献