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71.
The prognosis of small cell lung cancer (SCLC) remains poor with a 5‐year survival rate of 4–6%. In non‐small cell lung cancer (NSCLC), high levels of intact and cleaved forms of the receptor for urokinase plasminogen activator (uPAR) are significantly associated with short overall survival. Our aim was therefore to determine the prognostic value of the different uPAR forms in blood from SCLC patients. Serum samples from 92 treatment naive SCLC patients were analysed. Intact uPAR, uPAR(I–III), intact and cleaved uPAR, uPAR(I–III) + uPAR(II–III) and the liberated domain I, uPAR(I) were measured using time‐resolved fluorescence immunoassays (TR‐FIA 1–3). Assessment of association of the uPAR forms to overall survival (OS) was done using Cox regression analysis adjusted for clinical covariates [age, gender, stage, lactate dehydrogenase (LDH), WHO performance status (PS)]. Multivariate survival analysis demonstrated that high levels of uPAR(I) were significantly (p = 0.009) associated with short overall survival (OS). Patients with uPAR(I) levels above the second tertile had a hazard ratio (HR) of 1.9 (95% confidence interval (CI): 1.1–3.3), compared to patients with levels below the first tertile. High serum uPAR(I) levels are associated with short OS in SCLC patient, independent of LDH and PS.  相似文献   
72.
In order to develop more sensitive, specific, and rapid immunoassays to detect Salmonella enteritidis in food supplies, we have applied various approaches by using several different antibody preparations. Utilizing ELISA in both a plate and immunodot assay, we employed (i) a polycolonal rabbit antiserum to a boiled suspension of the organism; (ii) a monoclonal antibody to the cell surface of the bacterium; and (iii) mouse antisera to two oligosaccharides each containing the rare sugar tyvelose, and exhibited by S. enteritidis, a member of the group D salmonellae. We showed that the polyclonal antiserum and monoclonal antibody IG-10 to the cell surface could specifically detect from 10(2) to 10(3) organisms in a 10-microl sample in the plate and immunodot assay. Both assays are read in 4-5 hr. Further, in the mice immunized to the trisaccharide, (alpha-D-galactose-alpha-tyvelose-alpha-D-mannose), as well as those mice immunized to the tetrasaccharide, (alpha-D-galactose-alpha-tyvelose-alpha-D-mannose-alpha-L-rhamnose), specificity to tyvelose was determined by inhibition studies. The inhibitors of the antisera to the trisaccharide included the single sugar tyvelose conjugated to bovine serum albumin (BSA), a tetrasaccharide in which tyvelose is excluded, but contains alpha-D-galactose, alpha-ascarose, alpha-D-mannose, and alpha-L-rhamnose (conjugated to BSA), and others. The inhibition studies suggest that the mouse antisera are specific for tyvelose and also contain antibodies for mannose and rhamnose. The antibodies that have been made to the unique sugar tyvelose should improve the specificity in assays for S. enteritidis.  相似文献   
73.
74.
Antibody present in the transplant recipient that yields a positive crossmatch with donor cells has long been considered a contraindication and an absolute barrier to transplantation. However, improved methods of antibody detection and characterization have shown that some reactivity with donor cells may be inconsequential to transplantation. Furthermore, the development of treatment protocols to downregulate the humoral immune response has shown that the barrier of sensitization can be overcome, permitting safe transplantation of the sensitized patient. Both of these factors have not only led to an increased rate of transplantation among sensitized patients but have also added to our understanding of the immune response and immune regulation. Here, we review the characteristics of antibodies believed to be relevant to transplant success and the various approaches to dealing with them.  相似文献   
75.
Annual cycles of reproductive steroid metabolites were measured in urine collected from free-living and captive tropical endangered Fijian ground frogs (Platymantis vitiana) a terrestrial breeding. Free-living frogs were sampled on Viwa Island, Fiji and captive frogs were maintained in an outdoor enclosure in Suva, Fiji. Urinary estrone, progesterone and testosterone metabolite concentrations increased in male and female frogs after hCG challenges, with clear peaks in steroid concentrations 2 or 3 days after the challenges. There were annual cycles of testosterone metabolites in wild and captive males, and of estrone and progesterone metabolites in wild and captive females. Peaks of steroid concentrations in the wet season corresponded with periods of mating and egg laying in females in December and January. Steroid concentrations declined in January and February when maximum egg sizes in females were also declining. Body weights of wild male and vitellogenic female frogs showed annual cycles. Body weights of non-vitellogenic female frogs varied significantly between months, although there was no clear pattern of annual changes. Body weights of the 3 captive male frogs and 4 captive female frogs were similar to those of the wild frogs. Estrone metabolites were 80% successful in identifying non-vitellogenic females from males. The results suggest that the Fijian ground frog is a seasonal breeder with an annual gonadal cycle, and this species is likely to be photoperiodic. Urinary steroid measurements can provide useful information on reproductive cycles in endangered amphibians.  相似文献   
76.
This study aimed to evaluate 5 enzyme immunoassays for detecting human antibodies against Taenia solium in human serum and for the diagnosis of neurocysticercosis (NCC): DRG™, RIDASCREEN™, NOVATECH™, CYPRESS™, and IVD™. A collection of 114 reference serum samples were used. All sera were tested both by ELISA and by an immunoblot method (enzyme-linked immunoelectrotransfer blot [EITB]). When compared with EITB, the Ridascreen™ test had the best positive concordance rate (85.1-91.2%) and the NovaLisa test™ showed the optimal negative concordance rate (93.7-95.6%). All tests had a sensitivity under 72% and a specificity above 60%. The best sensitivity was obtained using Ridascreen™ test (71.4%). An optimal specificity was achieved by the NovaLisa test™. T. solium-positive sera all cross-reacted with E. granulosus positive samples. In the commercial assays evaluated here, the most appropriate ELISA test for screening may be the Ridascreen™ assay. Antibody detection seems to be not appropriate for NCC diagnosis because of its overall lack of sensitivity.  相似文献   
77.
Objectives: Comparison of a new monoclonal digoxin assay with three polyclonal digoxin assays for their cross-reactivity to digoxinlike immunoreactive factors (DLIF) and digoxin metabolites.

Design and Methods: Sixty-:six nondigitalized patient samples from 5 different groups: neonates, women in 3rd trimester pregnancy, and patients with liver or renal diseases, or undergoing organ transplants, and 139 samples from digoxin-treated patients of 4 categories (hospital sick, liver, renal, and outpatients) were compared in 4 different digoxin assays: (a) ACS™ Digoxin (ACS) developed for the automated chemiluminescent Ciba Corning ACS 180® system, (b) Baxter Stratus™ (Stratus, a fluoroimmunoassay), (c) Ciba-Corning MagicTM (Magic, a radioimmunoassay), and (d) an in-house radioimmunoassay (RIA). The ACSTM and RIA were also compared for their cross-reactivity to four principal digoxin metabolites.

Results and Conclusion: Among the nondigitalized specimens, no significant DLIF interference was found for all 4 assays among the pregnant women or liver and transplant patients. However, the neonates registered high DLIF interference with Magic™ and RIA, but none for ACS™ or Stratus™. DLIF interference in renal samples was highest in the Magic assay and lowest in RIA. Among the specimens with digoxin, a higher number of discrepant samples were found from the sick patients than from outpatients. In 75% of such discrepant samples, the ACS™ result was less than other assay results, suggesting DLIF as the probable cause. The two assays differed most in their cross-reactivity to the deglycated metabolites, digoxigenin and its mono-digitoxoside.  相似文献   

78.
OBJECTIVES

We examined the effect of long-term treatment with two doses of the angiotensin converting enzyme (ACE) inhibitor enalapril on various immunological variables in patients with chronic congestive heart failure (CHF).

BACKGROUND

Immunological mediators are increasingly recognized to play a pathogenic role in the pathophysiology of CHF. Whether ACE inhibitor therapy modifies immunological variables has not previously been investigated.

METHODS

Seventy-five patients (mean age 52 ± 11 years) with CHF were randomized between low- (5 mg daily) and high-dose (40 mg daily) enalapril in a double-blind trial. Circulating levels of immunological parameters (i.e., proinflammatory cytokines, chemokines and adhesion molecules) were measured at baseline, at 10 weeks and at the end of the study (34 weeks).

RESULTS

All immunological parameters, except soluble interleukin (IL)-6 receptor, were increased in CHF compared with 21 healthy controls. During the study immunoreactive IL-6 levels decreased (p < 0.05) and soluble IL-6 receptor increased (p < 0.05) during high-dose but not during low-dose enalapril therapy. Furthermore, IL-6 bioactivity decreased only during the high-dose (p < 0.001), resulting in a significant difference in change during treatment between the two dosage groups (p < 0.001). This decrease in IL-6 bioactivity was significantly associated with decreased interventricular septum thickness as assessed by echocardiography (r = 0.56, p = 0.013). No other variables changed during treatment.

CONCLUSIONS

In patients with severe CHF, high-dose enalapril therapy is associated with a significant decrease in IL-6 activity. However, despite treatment with a high-dose ACE inhibitor, a persistent immune activation exists in these patients which may be of importance for the progression of CHF.  相似文献   

79.
Abstract

Purpose. Atrial fibrillation (AF) has been associated with elevated levels of cardiac troponins; however, it is not clear if this association is independent of underlying cardiovascular disease. The aim of this study was to investigate the impact of AF on cardiac troponin I levels in a 75-year-old cohort from the general population, using a recently introduced, highly sensitive assay. Methods. All 75-year-old citizens in Asker and Baerum counties were invited to participate in a prevalence study of AF. High-sensitive troponin I (hs-TnI) levels were measured (Abbott Diagnostics) in serum samples collected from 62 subjects with AF and a gender-matched control group of 126 subjects in sinus rhythm. Results. Hs-TnI was detectable in all subjects (median 7.3 ng/L [range 3.0–88.7]). Patients with AF had higher levels than subjects in sinus rhythm (8.3 ng/L [3.7–88.7] vs. 6.8 ng/L [3.0–77.5]; p = 0.011). Male gender (p = 0.002), hypertension (p = 0.001), coronary heart disease (p < 0.001), heart failure (p < 0.001), prior stroke or transient ischemic attack (p = 0.013) and serum creatinine (p < 0.001) were all associated with higher levels of hs-TnI in univariate analysis. Heart failure and coronary heart disease remained significantly associated with hs-TnI in multivariate analysis, whereas the relation between AF and hs-TnI was no longer statistically significant. Conclusion. All subjects had detectable levels of hs-TnI. AF patients had higher hs-TnI levels than subjects in sinus rhythm; however, this difference was not statistically significant after adjustment for heart failure and coronary heart disease.  相似文献   
80.
Calprotectin (S100A8/A9), a protein expressed in neutrophils and monocytes/macrophages in circulation and inflamed tissue, is associated with measures of disease activity in rheumatoid arthritis (RA) patients both when measured in ethylenediaminetetraacetic acid (EDTA)-plasma and in serum. We wanted to explore if EDTA-plasma or serum should be preferred for calprotectin as a marker of disease activity. Calprotectin was analysed in EDTA-plasma and serum by enzyme-linked immunosorbent assay (ELISA) at baseline in 141 RA patients, starting biologic disease-modifying anti-rheumatic drugs (bDMARDs), and after three months. Differences between plasma and serum levels of calprotectin were assessed by Wilcoxon signed rank test. Variability was assessed by quartile coefficient of dispersion. Spearman’s test explored correlations between calprotectin in plasma and serum and between calprotectin (plasma or serum) and clinical/ultrasound (US) measures of disease activity. Bland Altman plots were used for method comparisons. Conventional inflammatory markers were evaluated for comparison. Calprotectin had similar variability when measured in plasma and serum, but there was a significant difference in concentrations between plasma and serum (p?s?=?0.62/0.46 for sum power Doppler score (PD), rs?=?0.60/0.48 for assessor’s global visual analogue scale (VAS), rs?=?0.59/0.43 for sum grey scale (GS) score and rs?=?0.47/0.37 for swollen joint count of 32, all p?相似文献   
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