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91.
Interleukin-8 serum concentrations after liver transplantation. 总被引:1,自引:0,他引:1
The study's objective was to investigate serum levels of interleukin-8 (IL-8) after liver transplantation and to correlate these findings with tumor necrosis factor alpha serum levels and various clinical parameters. This was a prospective observation study conducted at the University Hospital of Innsbruck with 19 patients studied after orthotopic liver transplantation. Serum levels of IL-8 were analyzed by a solid-phase double ligand ELISA method. Serum TNF-alpha concentrations were measured by means of a commercially available radio immunoassay (IRE-Medgenix, Fleurus, Belgium). Three patients with an uneventful recovery after transplantation showed IL-8 levels below the detection limit. IL-8 serum levels markedly increased in patients with acute graft rejection, bacterial infection, and CMV disease. Increments of serum IL-8 preceded clinical complications in all patients. Highest levels were observed in bacterial infection, lowest in acute rejection. A statistically significant positive correlation was demonstrated between IL-8 and TNF-alpha serum levels in the context of bacterial infection and CMV disease. Elevated IL-8 serum levels represent a feature of alloimmune and infectious complications following liver transplantation. IL-8 can thus be considered a further indicator molecule in the heterogenous group of acute-phase reactants that accompany various inflammatory responses and do not permit the underlying clinical complication to be specified. 相似文献
92.
The viscosity of solutions of poly(decyl methacrylate)s, PDMA, in 1-pentanol (thermodynamically poor solvent) and in toluence or isooctane (good solvents) was measured up to shear rates of 3 · 104s?1 by means of rotational viscosimeters. The observed pronounced shear thinning is for all solutions well described by the theory of Graessley, with the extension, introduced by Ito. Two parameters, resulting from the evaluation of the flow curves on the basis of the above theory, are discussed: τ0, a characteristic relaxation time of the polymer chain, is found to be in the range of ms. ηfric, a frictional parameter, independent of shear rate, amounts upto 50% of the zero-shear viscosity for the measured solutions. Both, τ0 and ηfric, increase with decreasing solvent quality, increasing molecular weight, and increasing concentration, in accord with theory. A comparatively sharp downward bend, separating two power-law regimes, shows up with moderately concentrated solutions, as the shear rate exceeds about 103 to 104 s?1. This transition is tentatively interpreted as an orientation of the long side chains of PDMA. 相似文献
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Bedenić B Schmidt H Herold S Monaco M Plecko V Kalenić S Katíc S Skrlin-Subić J 《Journal of chemotherapy (Florence, Italy)》2005,17(4):367-375
Plasmid-encoded resistance to broad-spectrum cephalosporins and aztreonam is becoming a widespread phenomenon in clinical medicine. These antibiotics are inactivated by an array of different extended-spectrum beta-lactamases (ESBLs) which have evolved by point mutations of parental TEM or SHV beta-lactamases. In a previous study conducted during 1994-1995, SHV-2, SHV-2a and SHV-5 beta-lactamases were found among Klebsiella pneumoniae isolates in Dubrava University Hospital. High prevalence of ESBLs among K. pneumoniae strains in this hospital (20%) required further investigation. In this investigation, beta-lactamases from 42 K. pneumoniae strains collected in 1997 and 15 in 2004 from Dubrava University Hospital, were characterized in order to study the evolution of plasmid-encoded resistance to extended-spectrum cephalosporins and aztreonam in that hospital over a prolonged study period. Susceptibility to antibiotics was determined by disk-diffusion and broth microdilution method. beta-lactamases were characterized by isoelectric focusing, determination of hydrolysis of beta-lactam substrates, polymerase chain reaction and sequencing of bla(SHV) genes. All K. pneumoniae strains and their Escherichia coli transconjugants produced beta-lactamase with an isoelectric point of 8.2. Based on sequencing of bla(SHV) genes enzymes of all transconjugants were identified as SHV-5 beta-lactamase which conferred on the producing isolates high level of ceftazidime and aztreonam resistance. In this study, an outbreak of nosocomial infections caused by SHV-5 producing K. pneumoniae was described in 1997 which evolved to endemic spread of SHV-5 producing K. pneumoniae due to multiple plasmid transfer in the Dubrava University Hospital. The strains from 1997 and 2004 were not clonally related. Hospital hygiene measures should be applied in order to control the spread of epidemic strains through the hospital wards and the consumption of the broad-spectrum cephalosporins needs to be restricted to reduce the selection pressure which enables the proliferation of ESBL producers in hospital. 相似文献
97.
Greater accuracy in positioning of the acetabular cup by using an image-free navigation system 总被引:4,自引:0,他引:4
Kalteis T Handel M Herold T Perlick L Baethis H Grifka J 《International orthopaedics》2005,29(5):272-276
In a prospective and randomised clinical study, acetabular cups were implanted free-hand (control group n=22) or with computer assistance using an image-free navigation system (study group n=23). The cup position was determined postoperatively on pelvic CT. An average inclination of 42.3° (range: 30°–53°; SD±7.0°) and an average anteversion of 24.0° (range: –3° to 51°; SD±15.0°) were found in the control group, and an average inclination of 45.0° (ranage: 40°–50°; SD±2.8°) and an average anteversion of 14.4° (range: 5°–25°; SS±5.0°) in the computer-assisted study group. The deviations from the desired cup position (45° inclination, 15° anteversion) were significantly lower in the computer-assisted study group (p<0.001 each). While only 11/22 of the cups in the control group were within the Lewinnek safe zone, 21/23 of the cups in the study group were placed in this target region (p=0.003).
Résumé Dans un étude clinique prospective et randomisé, les cupules acétabulaires ont été implantées de façon habituelle (n=22; groupe témoin) ou avec assistance dun ordinateur qui utilise un système de navigation image—libre (n=23; groupe détude). La place de la cupule a été déterminée après lopération sur un scanner pelvien. Une inclinaison moyenne de 42,3° (30° à 53°; ±7.0°) et une antéversion moyenne de 24,0° (–3° à 51°; ±15.0°) ont été trouvées dans le groupe témoin et une inclinaison moyenne de 45,0° (40° à 50°; ±2.8°) et une antéversion moyenne de 14,4° (5° à 25°; ±5.0°) dans le groupe de létude assistée par ordinateur. Les déviations par rapport à la position désirée de la cupule (45° dinclinaison, 15° dantéversion) étaient notablement inférieures dans le groupe de létude assistée par ordinateur (p<0.001 chacun). Alors que seulement 11 des 22 cupules du groupe témoin étaient dans la zone sûre de Lewinnek, 21 des 23 cupules du groupe détude ont été placées dans cette région cible (p=0.003).相似文献
98.
Tha-In T Hesselink DA Tilanus HW Elshove L Wilschut AL Hansen BE van Gelder T Metselaar HJ 《Clinical transplantation》2005,19(4):537-542
BACKGROUND: Recent studies suggest that cyclosporine dose adjustment based on C2 levels results in improvement of renal function. This study investigates the effect on renal function after dose reduction based on the C2 levels in long-term liver transplant patients. METHODS: In 60 patients (>1 yr after transplantation), C2 levels were assessed (target 600 ng/mL +/- 20%). Dose reduction was performed when C2 >720 ng/mL. Serum creatinine concentrations were measured and creatinine clearance was calculated. RESULTS: Twenty-three patients (38%) had C2 values >720 ng/mL. After dose reduction, mean cyclosporine dose decreased by 25% (p < 0.01). Mean C2 value decreased by 42% (p < 0.01). Serum creatinine concentrations remained stable. After dose reduction two patients experienced recurrence of PBC, in one patient AIH recurred and rejection was diagnosed in one patient. CONCLUSION: Cyclosporine C2 concentrations above 720 ng/mL are common in long-term liver transplant patients. Dose reduction of 25% did not improve kidney function and was accompanied by immune activation. 相似文献
99.
Despite extensive and ongoing investigations of the immune mechanisms of autoimmune diabetes in humans and animal models, there is much less information about the natural history of insulin secretion before and after the clinical presentation of type 1 diabetes and the factors that may affect its course. Studies of insulin production previously published and from the Diabetes Prevention Trial (DPT)-1 suggest that there is progressive impairment in insulin secretory responses but the reserve in response to physiological stimuli may be significant at the time of diagnosis, although maximal responses are more significantly impaired. Other factors, including insulin resistance, may play a role in the timing of clinical presentation along this continuum. The factors that predict the occurrence and rapidity of decline in beta-cell function are still largely unknown, but most studies have identified islet cell autoantibodies as predictors of future decline and age as a determinant of residual insulin production at diagnosis. Historical as well as recent clinical experience has emphasized the importance of residual insulin production for glycemic control and prevention of end-organ complications. Understanding the modifiers and predictors of beta-cell function would allow targeting immunological approaches to those individuals most likely to benefit from therapy. 相似文献
100.
Herold KC Gitelman SE Masharani U Hagopian W Bisikirska B Donaldson D Rother K Diamond B Harlan DM Bluestone JA 《Diabetes》2005,54(6):1763-1769
Despite advances in understanding autoimmune diabetes in animal models, there has been little progress in altering the natural course of the human disease, which involves progression to insulin deficiency. Studies with immunosuppressive agents have shown short-term effectiveness, but they have not induced tolerance, and continuous treatment is needed. We studied the effects of hOKT3gamma1(Ala-Ala), a humanized Fc mutated anti-CD3 monoclonal antibody, on the progression of type 1 diabetes in patients with recent-onset disease in a randomized controlled trial. In general, the drug was well tolerated. A single course of treatment, within the first 6 weeks after diagnosis, preserved C-peptide responses to a mixed meal for 1 year after diagnosis (97 +/- 9.6% of response at study entry in drug-treated patients vs. 53 +/- 7.6% in control subjects, P < 0.01), with significant improvement in C-peptide responses to a mixed meal even 2 years after treatment (P < 0.02). The improved C-peptide responses were accompanied by reduced HbA(1c) and insulin requirements. Clinical responses to drug treatment were predicted by an increase in the relative number of CD8(+) T-cells in the peripheral blood after the lymphocyte count recovered 2 weeks after the last dose of drug. We conclude that treatment with the anti-CD3 monoclonal antibody hOKT3gamma1(Ala-Ala) results in improved C-peptide responses and clinical parameters in type 1 diabetes for at least 2 years in the absence of continued immunosuppressive medications. 相似文献