In Vitro Differentiation of Human Skin-Derived Cells into Functional Sensory Neurons-Like.

Skin-derived precursor cells (SKPs) are neural crest stem cells that persist in certain adult tissues, particularly in the skin. They can generate a large type of cell in vitro, including neurons. SKPs were induced to differentiate into sensory neurons (SNs) by molecules that were previously shown to be important for the generation of SNs: purmorphamine, CHIR99021, BMP4, GDNF, BDNF, and NGF.

Comparison of the New, Rapid, and Fully Automated Kryptor TSH receptor Antibodies Assay (B.R.A.H.M.S.) with the Radioimmunological Assay (B.R.A.H.M.S.).

Background: Radioimmunoassays, which are often not automated and time-consuming, are gradually being re-placed in medical laboratories by non-radioactive methods that need to be evaluated. The purpose was to compare the measurement of thyroid-stimulating hormone receptor antibodies (TRAb) by the new Brahms' kit using Kryptor TRACE technology and the Brahms' radioimmunoassay.

Methods: We prospectively collected all samples from patients who received thyroid-stimulating hormone receptor antibodies testing in July 2018 at the University Hospital of Brest.

Systematic overestimation of human serum albumin by capillary zone electrophoresis method due to monoclonal immunoglobulin interferences.

Background: The capillary zone electrophoresis method of albumin measurement is frequently used in monoclonal gammopathy patients but some studies suggest poor performances of the method in this population. The aim of this study was to analyse the impact of serum monoclonal immunoglobulins on human serum albumin determination by capillary zone electrophoresis method compared to other available methods.

Method: We prospectively measured albumin in 100 freshly collected non-frozen serum samples in a monoclonal gammopathy patients population, by using four different methods: the capillary zone electrophoresis method, the bromocresol purple dye method, the nephelometric method and the turbidimetric method.

Is capillary zone electrophoresis a suitable method for estimating serum albumin: A comparison of four methods.

Background: The capillary zone electrophoresis method of albumin measurement is frequently used for oncologic and haematologic patients but few data exist about the agreement between the albumin measurements performed by capillary zone electrophoresis and other methods. The aim of this study was to analyse the agreement between human serum albumin measurements by capillary zone electrophoresis and by the nephelometry, bromocresol purple and turbidimetry methods.

Method: We prospectively measured 100 freshly collected non-frozen patient serum samples, by using four different methods: the capillary zone electrophoresis method performed with a CAPILLARYS 2 instrument, the bromocresol purple dye method performed with an Advia XPT analyser, the nephelometric method performed with a BN ProSpec analyser and the turbidimetric method with reagents from DiAgam and performed with the Advia XPT analyser.

[Biological diagnosis of pheochromocytoma: is there an interest in urinary metanephrines measurement over 3 consecutive days?].

Pheochromocytoma and paraganglioma are neuroendocrine tumors characterized by a catecholamine production potential. The biochemical diagnosis for this type of tumor is carried out through the metanephrine titration on 24-hours urines. Some authors have suggested that the sensitivity of the test could be improved by sampling and analyzing urines 3 days in a row (cycle) versus a unique measurement but this method has never been fully evaluated.

[Causes, consequences and treatment of hypophosphatemia: A systematic review].

Context: Although hypophosphatemia is usually very seldom, it can reach two to 3% of hospitalized patients and until 28% of intensive care unit patients. Due to the lack of knowledge, clinical practice regarding seeking or treatment of hypophosphatemia is very heterogenous. However its clinical consequences might be heavy.

TRPV1 and TRPA1 in cutaneous neurogenic and chronic inflammation: pro-inflammatory response induced by their activation and their sensitization.

Cutaneous neurogenic inflammation (CNI) is inflammation that is induced (or enhanced) in the skin by the release of neuropeptides from sensory nerve endings. Clinical manifestations are mainly sensory and vascular disorders such as pruritus and erythema. Transient receptor potential vanilloid 1 and ankyrin 1 (TRPV1 and TRPA1, respectively) are non-selective cation channels known to specifically participate in pain and CNI.

A non-hypocholesterolemic atorvastatin treatment improves vessel elasticity by acting on elastin composition in WHHL rabbits.

Background And Aims: Statins are prescribed for their preventative effects within atherosclerosis development. To our knowledge, no study focusing on very low-dose (non-hypolipidemic effect) and long-term atorvastatin treatment in vivo was available. Our aim was to assess the effect of such atorvastatin treatment on the mechanical and functional characteristics of arteries in the context of primary prevention.

[Pre-analytical stability before centrifugation of 7 biochemical analytes in whole blood].

The pre-analytical stability of 7 biochemical parameters (parathyroid hormone -PTH-, vitamins A, C E and D, 1,25-dihydroxyvitamin D and insulin) at +4 °C, was studied on whole blood samples before centrifugation. The impact of freezing at -20°C was also analyzed/performed for PTH and vitamin D. The differences in the results of assays for whole blood samples, being kept for different times between sampling time and analysis, from 9 healthy adults, were compaired by using a Student t test.

Self-maintenance of neurogenic inflammation contributes to a vicious cycle in skin.

Cutaneous neurogenic inflammation (CNI) is frequently associated with skin disorders. CNI is not limited to the retrograde signalling of nociceptive sensory nerve endings but can instead be regarded as a multicellular phenomenon. Thus, soluble mediators participating in communication among sensory nerves, skin and immune cells are key components of CNI.

Human cytochrome P450 4F3: structure, functions, and prospects.

Cytochrome P450 4F3 (CYP4F3), originally identified as one of the leukotriene B4 ω-hydroxylases, belongs to a CYP gene family that comprises several members, which participate in the metabolism of various endobiotics, as well as some xenobiotics. The CYP4F gene family is clustered in a 0.5-Mb stretch of genomic DNA on the p13 region of chromosome 19.

Statins increase cytochrome P450 4F3-mediated eicosanoids production in human liver cells: a PXR dependent mechanism.

In the present study, the ability of lovastatin, a competitive inhibitor of HMG-CoA reductase, to regulate the gene expression and function of Cytochrome P450 4F3B (CYP4F3B) was examined in the well differentiated HepaRG human hepatoma cell line. Statins induced CYP4F3B mRNA, protein and the production of 20-hydroxyeicosatetraenoic acid (20-HETE), a product of arachidonic acid metabolism and a peroxisome proliferator activated receptor (PPAR) ligand. This response was not dependent on cholesterol shortage or on sterol regulatory element binding protein activation.

CYP4F3B expression is associated with differentiation of HepaRG human hepatocytes and unaffected by fatty acid overload.

Fatty acid microsomal ω-oxidation involves cytochrome P450 enzymes. Some of them belonging to the CYP4F3 family are mainly expressed in the liver, making this organ a major player in energy homeostasis and lipid metabolism. To study this important regulation pathway, we used HepaRG cells, which gradually undergo a complete differentiation process.

Cytochromes P450 from family 4 are the main omega hydroxylating enzymes in humans: CYP4F3B is the prominent player in PUFA metabolism.

Human CYP450 omega-hydroxylases of the CYP4 family are known to convert arachidonic acid (AA) to its metabolite 20-hydroxyeicosatetraenoic acid (20-HETE). This study deals with hydroxylations of four PUFAs, eicosatrienoic acid (ETA), AA, eicosapentaenoic acid (EPA), and docosahexaenoic acid (DHA) by either human recombinant CYP4s enzymes or human liver microsomal preparations. CYP4F3A and CYP4F3B were the most efficient omega-hydroxylases of these PUFAs.

CYP4F3B is induced by PGA1 in human liver cells: a regulation of the 20-HETE synthesis.

The regulation of the human liver-specific cytochrome P450 4F3B (CYP4F3B) isoform, a splice variant of the CYP4F3 gene with strong substrate specificity for long chain fatty acids, is yet an unsolved question. This report provides the first evidence that CYP4F3B is uniquely induced by prostaglandin A1 (PGA1) in human hepatocyte-like HepaRG cells and leads to the synthesis of 20-hydroxy-eicosatetraenoic acids (HETEs). Real time PCR, immunoblot analysis with a specific antipeptide antibody, and determination of fatty acid omega-hydroxylase activity demonstrate that PGA1 treatment strongly increases expression of CYP4F3B.

CYP4A11 is repressed by retinoic acid in human liver cells.

CYP4A11, the major fatty acid omega-hydroxylase in human liver is involved in the balance of lipids, but its role and regulation are both poorly understood. We studied the effects of retinoids on the regulation of CYP4A11 in the human hepatoma cell line HepaRG. Treatment of HepaRG cells with all-trans-retinoic acid resulted in a strong decrease in CYP4A11 gene expression and apoprotein content and, furthermore, was associated with a 50% decrease in the microsomal lauric acid hydroxylation activity.

Human CYP4F3s are the main catalysts in the oxidation of fatty acid epoxides.

CYP4F isoforms are involved in the oxidation of important cellular mediators such as leukotriene B4 (LTB4) and prostaglandins. The proinflammatory agent LTB4 and cytotoxic leukotoxins have been associated with several inflammatory diseases. We present evidence that the hydroxylation of Z 9(10)-epoxyoctadecanoic, Z 9(10)-epoxyoctadec-Z 12-enoic, and Z 12(13)-epoxyoctadec-Z 9-enoic acids and that of monoepoxides from arachidonic acid [epoxyeicosatrienoic acid (EET)] is important in the regulation of leukotoxin and EET activity.