Comparability of a new turbidimetric digoxin test with other immunochemical tests and with HPLC--a multicenter evaluation.

A new turbidimetric inhibition immunoassay for digoxin (Tina-quant [a] Digoxin, Boehringer Mannheim) was evaluated in seven laboratories. It can be performed without sample pretreatment with ready-to-use reagents on nondedicated analyzers in combination with routine clinical chemistry. The studies revealed a good analytical performance: lower limit of detection 0.

Stepwise binary gradient high-performance liquid chromatographic system for routine drug monitoring.

Drug therapy is usually optimized by concentration measurement in patient serum. High-performance liquid chromatography (HPLC) is one of the most important analytical techniques used for therapeutic drug monitoring (TDM) of drugs for which no immunoassay kits are available. HPLC has been frequently used for screening purposes in toxicology, too.

[Immune paralysis in acute pancreatitis--HLA-DR antigen expression on CD14+DR+ monocytes].

Unlabelled: Determination of the prognosis in acute cases of pancreatitis, particularly in its serious and necrotizing form, still presents problems. Patients require intensive care and suffer from severe septic complications that do not correlate with pancreatic enzyme levels (amylase lipase).

Method: Thirty-one patients with acute pancreatitis were examined: group 1 -- necrotizing pancreatitis (lethal outcome n = 7); group 2 -- necrotizing pancreatitis (surviving n = 12); group 3 edematous pancreatitis (surviving n = 12).

Comparison of serum phospholipase A2, polymorphonuclear granulocyte elastase, C-reactive protein and serum amyloid A with the APACHE II score in the prognosis of multiple injured patients.

This prospective study of 35 multitraumatized intensive care unit patients requiring mechanical ventilation examined the relative utility of four biochemical parameters with a physiological scoring system for predicting lethal outcome. Levels of serum phospholipase A2 (PLA2), serum amyloid A (SAA), polymorphonuclear granulocyte elastase (PMN elastase), and C-reactive protein (CRP) were determined at short intervals during the patient's hospitalization. The first specimen was obtained at the time of admission, and subsequent specimens were drawn at 8 h intervals for the first 48 h and then twice daily until death or convalescence.

Fast HPLC determination of serum free fatty acids in the picomole range.

We developed a method for determining individual free fatty acids in serum by using a modified one-step Dole extraction, derivatization, and a new high-performance liquid chromatographic (HPLC) separation. Sample handling is minimized to a single transfer of the fatty acids (upper layer of the Dole extract), which are readily derivatized at 85 degrees C with p-bromophenacyl bromide without significant hydrolysis of esterified fatty acids. The derivatization mixture is directly injected into the HPLC apparatus.

Characteristics and clinical application of a radiometric Escherichia coli-based phospholipase A2 assay modified for serum analysis.

Determination of activities of phospholipase A2 (PLA2) in human sera was based on the hydrolysis of phospholipids from [1-14C]oleic acid-labeled Escherichia coli biomembranes. The E. coli membranes served as substrate specifically for the PLA2 of human serum and were essentially resistant to other lipases in human sera, i.

[Studies of lipid and lipoprotein metabolism in man after surgical interventions].

The pattern of serum lipids and lipoproteins was investigated before and after surgery in 77 patients with respect to the "acute-phase reaction". Special attention was paid to the severity of the surgical trauma and the time course of postoperative alterations. Therefore, 12 different serum parameters were measured in 18 patients just before surgery and on days 1, 3, 5 and 10.

Fatty acid modulation of HepG2 cell cholesterol biosynthesis and esterification.

We investigated the effects of medium supplementation with increasing amounts of different fatty acids on HepG2 cell cholesterol biosynthesis and esterification. Up to 200 microM 16:0 led to an increase in cholesterol secretion/synthesis of 60%/40%; 18:1, 18:2, or 18:3 decreased secretion/synthesis by 35%/25%, 65%/65%, and 60%/60%; 80 microM 20:5 caused a reduction of 75%/50%. Compared to 200 microM 16:0, 18:2 led to a 50% reduced cellular cholesterol ester biosynthesis; the effect of 30 microM 20:5 was comparable to that of 18:2 while the addition of 200 microM 18:1 raised esterification.

Results of the multicenter evaluation of the CEDIA cortisol assay.

The present paper describes the multicenter evaluation of the CEDIA Cortisol test for total cortisol. The observed linearity of the test was between 1.2 and 50 micrograms/dL cortisol.

Results of the multicenter evaluation of the CEDIA Phenobarbital assay.

The CEDIA Phenobarbital assay has been evaluated in twelve clinical laboratories in Europe and U.S.A.

Results of the multicenter evaluation of the CEDIA Phenytoin assay.

Thirteen clinical evaluation sites in Europe and U.S.A.

Results of the multicenter evaluation of the CEDIA Theophylline assay.

We report on the results of the multicenter evaluation of the CEDIA Theophylline assay on Boehringer Mannheim/Hitachi analyzers in 15 clinical laboratories in Europe and U.S.A.

Liquid chromatographic analysis of phenobarbital, phenytoin, and theophylline.

Sera from the routine of therapeutic drug monitoring were assayed for phenobarbital, phenytoin, and theophylline with three different methods: fluorescence polarization immunoassay as the standard procedure, the new CEDIA assays within a multicenter evaluation and HPLC which is known to yield results with a high specificity. CVs for between-day imprecision ranged from 2.6-8.

Improved method for enzymic determination of cholesterol in lipoproteins separated by electrophoresis on thin layer agarose gels.

The cholesterol of lipoproteins, separated electrophoretically on thin layer agarose films, is visualised and quantitated by incubating the gels in an enzymic reagent containing cholesterol esterase and cholesterol dehydrogenase. The individual fractions are quantitated by scanning densitometry. No sample pretreatment is necessary.

Enzymatic determination of lipids in human bile without bilirubin interference: reliable assessment of the cholesterol saturation index (CSI).

We describe a simple and rapid, but nevertheless precise and accurate method for the enzymatic determination of the main lipid constituents in human bile. Interfering bile pigments, especially bilirubin are eliminated by the use of aminopropyl bonded phase columns ("Bond-Elut") prior to the enzymatic measurement of cholesterol and lecithin. Intra-assay imprecision was between 3.

[Risk indicators of urinary calculus formation: value of oxalate and citrate excretion in comparison with the oxalate tolerance value].

Several methods for the measurement of crystallization conditions in urine, the so-called whole urine systems, have recently been of considerable interest in urolithiasis research. The diagnostic accuracy of the oxalate tolerance value (OTV) was therefore compared with the daily excretion of oxalate and citrate in normal persons and patients with urinary calculi. With the aid of the oxalate/citrate ratio, 77% of the patients could be classified correctly.

A specific method for the direct determination of lipoprotein cholesterol in electrophoretic patterns.

Lipoproteins are separated electrophoretically and cholesterol is visualised with an enzymic reagent specific for cholesterol in which the gels are incubated. Quantitation of the individual fractions is accomplished by scanning densitometry. No sample pretreatment is necessary.

Investigation of the performance of the ES 600 Enzymun-Test system. A multicentre study.

The ES 600 sample-selective multibatch analyser was subjected to a multicentre evaluation in six laboratories in accordance with ECCLS guide-lines. During the 3-month trial, five Enzymun-Test diagnostics (T4, TBG, Digoxin, CEA and TSH)1) were measured at 25 degrees C. The study yielded the following results: 1.