Comparison between radiometry and spectrophotometry for the determination of angiotensin-converting enzyme activity in cerebrospinal fluid.

Determination of angiotensin-converting enzyme (ACE) activity in cerebrospinal fluid (CSF) can help for establishing the diagnosis of neurosarcoidosis. We investigated the performance characteristics of two assays for ACE determination in 57 CSF, radiometry with [glycine-1-14C] benzoyl-L-histidyl-L-leucine and spectrophotometry with furylacryloyl-phenylalanyl-L-glycyl-L-glycine (FAPGG) as substrates. We compared both kinetic assays to an ELISA specific for human ACE.

[Measurement of angiotensin-I-converting enzyme in the blood: help for method validation].

Blood angiotensin-converting enzyme (ACE) assay is now realized by the determination of enzyme activity on synthetic substrate, mostly furylacryloyl-phenylalanyl-L-glycyl-L-glycine (FAPGG). The matrix can be serum or heparin-plasma, with or without a separator; the assay developed on serum or plasma is not adapted to other matrix such as cerebrospinal fluid where the ACE activity is much lower. This assay has been adapted on a number of automated biochemistry analyzers with the specifications of the supplier of reagents, sometimes with modification of volumes or times for analysis.

Multi-centre evaluation of recent troponin assays for the diagnosis of NSTEMI.

Objectives: We aimed to compare the use of nine different cardiac troponin (cTn) assays (2 cTnT and 7 cTnI) for the diagnosis of NSTEMI in a single multi-centre population.

Design And Methods: One hundred and fifty-eight patients were included (mean age 60 years, SD 17 years), including 23 patients (14%) with NSTEMI.

Results: The analytical comparison highlighted a large heterogeneity of cTn assays, as reflected by percentages of patients with detectable cTn, correlation coefficients, Passing-Bablok comparisons and concordance coefficients.

Search for biomarkers of neurosarcoidosis by proteomic analysis of cerebrospinal fluid.

Sarcoidosis is a systemic granulomatous disease, which mostly affects lung. Central nervous system can be affected causing a neurosarcoidosis in 5 to 15% of all sarcoidosis patients. The definitive diagnosis is established on histological examination of brain granulomas.

Angiotensin-converting enzyme insertion/deletion gene polymorphism in a Tunisian healthy and acute myocardial infarction population.

Introduction: The role of the insertion/deletion (I/D) polymorphism in the angiotensin-converting enzyme gene (ACE) on acute myocardial infarction (AMI) is controversial.

Objectives: To assess the effect of the ACE I/D polymorphism on AMI compared with the healthy controls and its relationship with serum ACE activity in a Tunisian population.

Design And Methods: A total of 119 patients with AMI were compared with 238 healthy controls from the same geographical area.

False elevation of blood lactate reveals ethylene glycol poisoning.

Ethylene glycol poisoning is a medical emergency. Making a definitive diagnosis is challenging because few institutions have timely access to direct measurement of ethylene glycol. After ingestion, primary metabolism of ethylene glycol takes place in the liver, leading to glycolic acid and glyoxylic acid.

Point-of-care testing: false elevation of cardiac troponin I assayed in the emergency department.

In October 2007, an 18-year-old woman with no cardiac history was admitted to the emergency department for a major epigastric pain. The chest pain led to assay cardiac troponin I (cTnI) with the emergency department point-of-care testing analyzer (Stratus CS), which disclosed a value of 0.70 ng/mL, discordant with the atypical clinical presentation and the noncontributive electrocardiography.

Evaluation of the GEM Premier 4000: a compact blood gas CO-Oximeter and electrolyte analyzer for point-of-care and laboratory testing.

Background: GEM Premier 4000 (Instrumentation Laboratory), a new blood gas/CO-Oximeter/hematocrit/electrolyte/glucose/lactate analyzer was evaluated. The only reagents required were disposable cartridges (GEM Premier 4000 PAK comprise all components necessary for analysis, including quality controls).

Methods: The evaluation was performed in two laboratories according to the Valtec protocol guidelines.

Evaluation of the blood gas analyzer Gem PREMIER 3000.

During the past few decades, new technologies have allowed the fabrication of miniaturized sensors and the development of analyzers well designed for point-of-care testing (POCT). They combined the ease-of-use and portability required for POC with the accuracy and the reliability of traditional systems. Instrumentation Laboratory introduced the GEM Premier 3000, a compact and portable system to rapidly analyze pH, pCO2, PO2, Ca2+, Na2+, K+, lactate, glucose and hematocrit, from 135 microl of whole blood with a simple component: a cartridge, the GEM Premier Pak.