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101.
102.
Strümper D Durieux ME Hollmann MW Tröster B den Bakker CG Marcus MA 《Anesthesiology》2003,98(6):1356-1362
BACKGROUND: Antidepressants are frequently used in chronic pain therapy and are under investigation as long-acting local anesthetics. Because of the structural similarities between antidepressants and local anesthetics, the authors hypothesized that these compounds act similarly, and they investigated the effects of nortriptyline, amitriptyline, imipramine, and fluoxetine on priming and activation of human polymorphonuclear neutrophils (hPMNs). METHODS: Effects of 30-, 120-, and 240-min preincubation with nortriptyline (10(-7)-10(-4) M), amitriptyline (10(-6)-10(-3) M), imipramine (10(-6)-10(-3) M), or fluoxetine (10(-7)-10(-4) M) on O(2)- generation of platelet activating factor-primed (10-6 M) and/or formyl-methionyl-leucyl-phenylalanine-activated (10(-6) M) isolated hPMNs were determined. All data are reported as mean +/- SD (statistics: t test, P < 0.05). RESULTS: Brief incubation in low concentrations of nortriptyline, amitriptyline, or fluoxetine (all at 10(-5) M) did inhibit priming but not activation of hPMNs. Imipramine (10(-5) M) affected neither priming nor activation. Prolonged incubation in lower concentrations of all antidepressants influenced neither priming nor activation. However, at higher concentrations, all four compounds exerted cytotoxic effects: virtually all hPMNs were killed by amitriptyline and imipramine (both at 10(-3) M) or nortriptyline and fluoxetine (both at 10(-4) M). CONCLUSION: Antidepressants, in low concentrations, inhibited priming but not activation of hPMNs. However, at concentrations similar to those attained after local injection, and in marked contrast to local anesthetics, antidepressants are profoundly toxic to hPMNs. 相似文献
103.
Strümper D Durieux ME Tröster B Hahnenkamp K Vitan C den Bakker CG Hollmann MW 《Anesthesiology》2003,99(4):911-917
BACKGROUND: Tricyclic antidepressants are structurally related to local anesthetics, suggesting that part of their analgesic action may result from properties shared with local anesthetics. Because local anesthetics block G protein-coupled receptor signaling (which explains, in part, their inflammatory modulating properties), the authors studied whether antidepressants have similar effects. METHODS: Peak Ca-activated Cl currents induced in Xenopus laevis oocytes by lysophosphatidic acid (10(-4) m) were measured using a voltage clamp. The effects of a 30-, 120-, or 240-min incubation in amitriptyline, nortriptyline, imipramine, or fluoxetine were determined. RESULTS: After a 30-min incubation, low concentrations (10(-7)-10(-5) m) of antidepressants had no effect on lysophosphatidic acid-induced currents. After prolonged incubation, only amitriptyline or nortriptyline inhibited lysophosphatidic acid signaling (each to 58% of the control response at 10(-7) m after 240 min). At low concentrations, none of the compounds induced membrane damage (defined as a holding current of > 1 microA, 2% in control cells). Imipramine at 10(-3) m induced damage in 100% of oocytes, and fluoxetine at 10(-4) m induced damage in 71% of oocytes (P < 0.05 vs. control). Amitriptyline and nortriptyline had no effect. CONCLUSIONS: These findings are in part different from those obtained with local anesthetics and suggest that interference with G protein-coupled signaling might explain, in part, the analgesic properties of some antidepressants. However, use of antidepressants in high concentrations may be associated with cellular toxicity. 相似文献
104.
Olsen CM Meussen-Elholm ET Samuelsen M Holme JA Hongslo JK 《Pharmacology & toxicology》2003,92(4):180-188
Bisphenol A is extensively used in the manufacturing of epoxy resins and polycarbonate plastics, whereas several brominated and chlorinated analogues are used as flame retardants and intermediates in the plastic industry. Due to the structural relationship between these chemicals and the high production volumes, we wanted to characterize and compare their potential oestrogen-like potency using several end-points in MCF-7 cells: induction of pS2 protein and progesterone receptor, reduction of oestrogen receptor level, and stimulation of cell growth. Bisphenol A, tetrachloro- and tetrabromo-bisphenol A, 4-hydroxybiphenyl and 4,4'-dihydroxybiphenyl all showed oestrogen-like properties in MCF-7 cells. The chemicals tested had affinity to the oestrogen receptor isolated from MCF-7 cells, although their EC50s were 1,000 to 80,000 times higher than the EC50 of 17beta-oestradiol. Bisphenol A and 4-hydroxybiphenyl induced cell growth in MCF-7 cells, and the highest test concentrations induced responses, apparently exceeding the cell growth induced by 17beta-oestradiol. The other chemicals tested induced less than 50% of the maximum 17beta-oestradiol-stimulated cell growth. Bisphenol A, 4-hydroxybiphenyl, tetrabromobisphenol A and tetrachlorobisphenol A all increased the level of the oestrogen-regulated proteins, progesterone receptor and pS2, whereas 4,4'-dihydroxybiphenyl showed no such effect. Bisphenol A was the only chemical tested that clearly mimicked 17beta-oestradiol in its ability to reduce the level of cytosolic oestrogen receptors in MCF-7 cells. By measuring several oestrogen-dependent endpoints it seems that some xeno-oestrogens cause an imbalanced oestrogen-response. Their ability and potency in mimicking 17beta-oestrogen in one parameter is not necessarily accompanied by a similar effect in another oestrogen-linked parameter. 相似文献
105.
Pediatric renal transplantation with mycophenolate mofetil-based immunosuppression without induction: results after three years 总被引:6,自引:0,他引:6
Jungraithmayr T Staskewitz A Kirste G Böswald M Bulla M Burghard R Dippell J Greiner C Helmchen U Klare B Klaus G Leichter HE Mihatsch MJ Michalk DV Misselwitz J Plank C Querfeld U Weber LT Wiesel M Tönshoff B Zimmerhackl LB;German Pediatric Renal Transplantation Study Group 《Transplantation》2003,75(4):454-461
BACKGROUND: Mycophenolate mofetil (MMF)-based immunosuppression has reduced the acute rejection rate in adults and in children in the early posttransplantation period. Three-year posttransplantation results have been reported for adults but not for children thus far. In the present open-labeled study, patients 18 years old and younger were evaluated prospectively for up to 3 years after renal transplantation (RTX). METHODS: Eighty-six patients receiving MMF in combination with cyclosporine and prednisone without induction were evaluated for patient survival, transplant survival, renal function, arterial blood pressure, adverse events, and opportunistic infections. These patients were compared with a historic control group (n=54) receiving azathioprine (AZA) instead of MMF. RESULTS: Patient survival after 3 years was 98.8% in the MMF group and 94.4% in the AZA group (NS). Intent-to-treat analysis of graft survival demonstrated superiority for MMF (98% vs. 80%; P<0.001). Cumulative acute rejection episodes occurred in 47% of patients in the MMF group versus 61% in the AZA group (P<0.05). Renal function was not significantly different, neither after 3 years nor in the long-term calculation. Antihypertensive medication was administered to 73% to 84% of patients, similar in both groups. Opportunistic infections were recorded only for MMF. Infection rates were comparable to those reported in adults. CONCLUSIONS: These results suggest that MMF is safe and beneficial as a longer term maintenance immunosuppressive drug in children and adolescents. 相似文献
106.
Radiologic mimics of juvenile rheumatoid arthritis 总被引:1,自引:0,他引:1
Established criteria for diagnosis of juvenile rheumatoid arthritis require consideration of a number of other joint arthropathies
and arthritides. In this pictorial essay, we present an approach to those common and uncommon disorders that should be considered
and may be mistaken for juventile rheumatoid arthritis.
Received: 22 May 2000 Accepted: 14 November 2000 相似文献
107.
Picherit C Horcajada MN Mathey J Chanteranne B Puel C Lebecque P Davicco MJ Coxam V Barlet JP 《Annals of nutrition & metabolism》2003,47(2):70-77
Some controversy exists in the literature concerning the effects of leptin on bone metabolism. Thus we have compared femoral bone density and biochemical markers of bone metabolism in male and female fatty (leptin-resistant) Zucker rats and their lean homozygous controls at 3 and 6 months of age. At 3 months, no differences concerning total, diaphyseal (cortical bone), and distal metaphyseal (trabecular bone) femoral bone densities, plasma osteocalcin concentrations, and urinary deoxypyridinoline excretion were observed between fatty and lean rats. On the opposite, at 6 months of age, in both males and females, total, diaphyseal, and distal metaphyseal femoral bone densities and plasma osteocalcin concentrations were lower in Zucker than in lean rats. Soybean isoflavone consumption (40 microg/g body weight/day for 90 days, a dose which prevents osteopenia following ovariectomy both in lean Zucker homozygous controls and in Wistar rats) by obese female Zucker rats had no significant effect upon their bone mass. 相似文献
108.
Christel Van Kerckhoven Hilde Van den Broeck Georges Smets Jos Huybrechts 《Macromolecular chemistry and physics.》1991,192(1):101-114
The iniferter method of Otsu was studied for the synthesis of polyvinyl block copolymers of relatively low molecular weight using tetramethylthiuram disulfide (TD) and benzyl N,N-diethyldithiocarbamate (BDC) as initiator. Considering the low quantum yield of dissociation (?d) of TD (2,5 · 10?3 in cyclohexane), TD was used as thermal initiator (95°C) for the synthesis of dithiocarbamate-polystyrene (TD-PS) telechelics. 13C NMR analysis of this TD-PS shows two 13C?S signals corresponding to two different end-groups: Et2N? CS? S? CH(C6H5)? CH2? and Et2N? CS? S? CH2? CH(C6H5)? . Several styrene polymerizations were also carried out in presence of azoisobutyronitrile (AIBN) as thermal initiator and TD as chain-transfer reagent. Depending on the mole ratio AIBN/TD, mono- and difunctional TD-PS's are formed, as evidenced by NMR analysis. These TD-PS's were used for the photochemical initiations of ethyl acrylate (EA), acrylic acid (AA) and methyl methacrylate (MMA). It is assumed that the quantum yield of dissociation of the dithiocarbamate end-group is equal to that of BDC (?d : 0,06). TD-PS nonfunctional polymers were also prepared, either photochemically by dissociation of BDC, or thermally in presence of AIBN and BDC as transfer agent. They were used for block copolymerization with MMA. Inversely, TD-PMMA's were prepared in a first step; in this case ?d = 0,026. They were then used for the polymerization of EA. The block copolymers were fractionated; their composition and molecular weights were determined by 1H NMR and gelpermeation chromatography, respectively. 相似文献
109.
110.
Hanen Abouda Yosr Hizem Amina Gargouri Christel Depienne Delphine Bouteiller Florence Riant Elisabeth Tournier‐Lasserve Isabelle Gourfinkel‐An Eric LeGuern Riadh Gouider 《Epilepsia》2010,51(9):1889-1893
Causative genes for childhood absence epilepsy (CAE) are unknown partly because families are small or phenotypically heterogeneous. In five consanguineous Tunisian families with at least two sibs with CAE, 14 patients fulfilled the diagnostic criteria for CAE (Epilepsia 1989;30:389–399). Linkage analyses or direct sequencing excluded CACNG2, CACNA1A, CACNB4, and CACNA2D2, orthologs of genes responsible for autosomal recessive (AR) absence seizures in mice. These families will help identify (a) gene(s) responsible for CAE. 相似文献