[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.

Proteinuria typing: how, why and for whom?

The typing of proteinuria is one of the complementary examinations carried out during the exploration of proteinuria. It aims to separate and identify the different proteins, or fractions of proteins, that make up proteinuria. The nature and relative importance of the proteins present reflect the location of the renal involvement and help to determine the etiology.

Sweat chloride quantification using capillary electrophoresis.

Background: Cystic fibrosis (CF) is the less rare and severe genetic disease among the European population. Biochemical diagnosis of CF is based on the demonstration of increased chloride concentration in sweat samples, obtained during the sweat test (ST). WynSep developed a capillary electrophoresis with contactless conductivity detection (CE-C4D) able to measure sweat chloride with a low sample volume.

Preanalytical step of urinary protein measurement: from urine sampling to preparation for analysis of the specimen.

The preanalytical phase is a key step in urinary protein measurement. It is a complex step, which includes urine sampling, storage and transport to the laboratory and preparation for analysis of the specimen. It can lead to numerous errors, since urine sampling is made by the patient himself.

CCDC115-CDG: A new rare and misleading inherited cause of liver disease.

Congenital disorders of glycosylation (CDG) linked to defects in Golgi apparatus homeostasis constitute an increasing part of these rare inherited diseases. Among them, COG-CDG, ATP6V0A2-CDG, TMEM199-CDG and CCDC115-CDG have been shown to disturb Golgi vesicular trafficking and/or lumen pH acidification. Here, we report 3 new unrelated cases of CCDC115-CDG with emphasis on diagnosis difficulties related to strong phenotypic similarities with mitochondriopathies, Niemann-Pick disease C and Wilson Disease.

Serum allantoin and aminothiols as biomarkers of chronic heart failure.

Background Oxidative stress (OS) represents the primary mediator of chronic heart failure (CHF) development and progression. It is well established that homocysteine is able to generate reactive oxygen species. Small amounts of allantoin in human serum result from free radical action on urate and may provide a stable marker for in vivo free radical activity.

Homocysteine in Chronic Heart Failure.

Background: Hyperhomocysteinemia (HHcy) is a risk factor for cardiovascular disease. Homocysteine (Hcy) can generate reactive oxygen species. Oxidative stress enhances the progression of cardiovascular diseases and has long been implicated in chronic heart failure (CHF).

[Urinary protein electrophoresis, which analysis to select? A simplified interpretation].

Permanent proteinuria is an early marker of the kidney dysfunction. Tracking by urinary strip, imposes a precise quantification by the laboratory. In front of the difficulties of urine collection during 24 hours, protein determination can be carried out on the urine of a miction and can be expressed as g per g of creatinine (uPCR).

Simultaneous determination of allantoin, hypoxanthine, xanthine, and uric acid in serum/plasma by CE.

Allantoin (All) is an oxidative end product of purines in mammals. The small amount of All present in human plasma or serum results from free radical action on urate and may provide a stable marker of in vivo free radical activity. Because free radicals have been implicated in the development and progression of atherosclerosis, this study focused on the metabolic compounds of the All pathway.