Publications by authors named "Arthus M"

Incidental capture of non-target species poses a pervasive threat to many marine species, with sometimes devastating consequences for both fisheries and conservation efforts. Because of the well-known importance of vocalizations in cetaceans, acoustic deterrents have been extensively used for these species. In contrast, acoustic communication for sea turtles has been considered negligible, and this question has been largely unexplored.

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Fibropapillomatosis (FP) threatens the survival of green turtle (Chelonia mydas) populations at a global scale, and human activities are regularly pointed as causes of high FP prevalence. However, the association of ecological factors with the disease's severity in complex coastal systems has not been well established and requires further studies. Based on a set of 405 individuals caught over ten years, this preliminary study provides the first insight of FP in Martinique Island, which is a critical development area for immature green turtles.

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Context: Familial pituitary diabetes insipidus has been described only in an autosomal dominant or recessive mode of inheritance.

Objective: This work aims to determine the cause of a novel form of familial diabetes insipidus (DI) that is controlled by desmopressin therapy but segregates in an X-linked recessive manner.

Methods: Thirteen members from 3 generations of the kindred with familial DI were studied.

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Aquaporin-2 (AQP2) is a homotetrameric water channel responsible for the final water reuptake in the kidney. Disease-causing AQP2 mutations induce nephrogenic diabetes insipidus (NDI), a condition that challenges the bodily water balance by producing large urinary volumes. In this study, we characterize three new AQP2 mutations identified in our lab from NDI patients (A120D, A130V, T179N) along the previously reported A47V variant.

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Objectives: Orphan medicinal products (OMPs) often receive market authorization under conditions imposed by regulators for ongoing postauthorization surveillance (PAS) to answer questions that remain at the time of market entry. This surveillance may be provided through industry-funded registries (IFRs). Nevertheless, data in these registries may not be of sufficient quality to answer these questions and may not always be accessible for regulatory review.

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Fabry disease is an X-linked lysosomal storage disorder caused by mutations in the gene encoding the α-galactosidase A enzyme. This enzyme cleaves the last sugar unit of glycosphingolipids, including globotriaosylceramide (Gb), globotriaosylsphingosine (lyso-Gb), and galabiosylceramide (Ga). Enzyme impairment leads to substrate accumulation in different organs, vascular endothelia, and biological fluids.

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Background: Inherited nephrogenic diabetes insipidus (NDI) is a rare disorder characterized by impaired urinary concentrating ability. Little clinical data on long-term outcome exists.

Method: This was a single-centre retrospective medical record review of patients with a diagnosis of NDI followed between 1985 and 2017.

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Fabry disease is an X-linked lysosomal storage disorder with marked variability in the phenotype and genotype. Glycosphingolipids such as globotriaosylceramide (Gb) isoforms/analogs, globotriaosylsphingosine (lyso-Gb) and analogs, and galabiosylceramide (Ga) isoforms/analogs may accumulate in biological fluids and different organs. The aims of this study were to: 1) develop/validate a novel UHPLC-MS/MS method for relative quantitation of Gb in leukocytes (unfractionated white blood cells), B lymphocytes and monocytes; 2) evaluate these biomarkers in a cohort of Fabry patients and healthy controls; and 3) assess correlations between these biomarkers, treatment and genotype.

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Aims/hypothesis: High plasma copeptin, a marker of vasopressin (VP) secretion, has been shown to be associated with the metabolic syndrome and development of type 2 diabetes in humans. The present study was designed to determine the long-term influence of plasma VP concentration in a rodent model prone to metabolic dysfunction.

Methods: Obese Zucker rats and their lean counterparts were submitted for 4 weeks to one of three protocols inducing different levels of VP.

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It is clinically useful to distinguish between two types of hereditary nephrogenic diabetes insipidus (NDI): a 'pure' type characterized by loss of water only and a complex type characterized by loss of water and ions. Patients with congenital NDI bearing mutations in the vasopressin 2 receptor gene, AVPR2, or in the aquaporin-2 gene, AQP2, have a pure NDI phenotype with loss of water but normal conservation of sodium, potassium, chloride and calcium. Patients with hereditary hypokalemic salt-losing tubulopathies have a complex phenotype with loss of water and ions.

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Aquaporin-2 (AQP2), located at the luminal side of the collecting duct principal cells, is a water channel responsible for the final concentration of urine. Lack of function, often occurring through mistargeting of mutated proteins, induces nephrogenic diabetes insipidus (NDI), a condition characterized by large urinary volumes. In the present study, two new mutations (K228E and V24A) identified in NDI-affected individuals from distinct families along with the already reported R187C were analysed in comparison to the wild-type protein (AQP2-wt) using Xenopus laevis oocytes and a mouse collecting duct cell-line (mIMCD-3).

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Article Synopsis
  • Aquaporin-2 (AQP2) is a vital water channel in the kidneys, and mutations in AQP2 lead to nephrogenic diabetes insipidus (NDI), which causes excessive urination and thirst.
  • Researchers studied patients with NDI who had specific genetic mutations (D150E and G196D) affecting AQP2, comparing their functions in a lab setting using frog cells (Xenopus oocytes).
  • Results showed that while the normal AQP2 protein greatly increases water permeability, the D150E mutation reduces it, and the G196D mutation results in no water transport, illustrating a dominant negative effect when both mutations are present.
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We evaluated a baby boy with severe combined immunodeficiency (SCID) and X-linked nephrogenic diabetes insipidus (NDI). This patient had less than 10% CD3+ T cells, almost all of which were positive for CD4 and CD45RO. Genetic studies demonstrated a 34.

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In many mendelian diseases, some mutations result in the synthesis of misfolded proteins that cannot reach a transport-competent conformation. In X-linked nephrogenic diabetes insipidus, most of the mutant vasopressin 2 (V2) receptors are trapped in the endoplasmic reticulum and degraded. They are unable to reach the plasma membrane and promote water reabsorption through the principal cells of the collecting ducts.

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Vasopressin regulates water homeostasis through insertion of homotetrameric aquaporin-2 (AQP2) water channels in the apical plasma membrane of renal cells. AQP2 mutations cause recessive and dominant nephrogenic diabetes insipidus (NDI), a disease in which the kidney is unable to concentrate urine in response to vasopressin. Until now, all AQP2 mutants in recessive NDI were shown to be misfolded, retained in the endoplasmic reticulum (ER) and unable to interact with wild-type (wt)-AQP2, whereas AQP2 mutants in dominant NDI are properly folded and interact with wt-AQP2, but, due to the mutation, cause missorting of the wt-AQP2/mutant complex.

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In most cases, nephrogenic diabetes insipidus results from mutations in the V2 vasopressin receptor (V2R) gene that cause intracellular retention of improperly folded receptors. We previously reported that cell permeable V2R antagonists act as pharmacological chaperones that rescue folding, trafficking, and function of several V2R mutants. More recently, the vasopressin antagonist, SR49059, was found to be therapeutically active in nephrogenic diabetes insipidus patients.

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Vasopressin regulates body water conservation by redistributing aquaporin-2 (AQP2) water channels from intracellular vesicles to the apical surface of renal collecting ducts, resulting in water reabsorption from urine. Mutations in AQP2 cause autosomal nephrogenic diabetes insipidus (NDI), a disease characterized by the inability to concentrate urine. Here, we report a frame-shift mutation in AQP2 causing dominant NDI.

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Background: An increase in urinary albumin excretion (UAE) represents an early predictor of glomerular damage in diabetes mellitus (DM) and a risk factor for cardiovascular complications in hypertension. Vasopressin is elevated in DM and in some forms of hypertension. Previous studies in rats suggested that this hormone could play a role in the albuminuria observed in chronic renal failure or diabetic nephropathy, but no information is available concerning the mechanism of these effects and the possible influence of vasopressin on UAE in the healthy kidney.

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Mutations in the Aquaporin-2 gene, which encodes a renal water channel, have been shown to cause autosomal nephrogenic diabetes insipidus (NDI), a disease in which the kidney is unable to concentrate urine in response to vasopressin. Most AQP2 missense mutants in recessive NDI are retained in the endoplasmic reticulum (ER), but AQP2-T125M and AQP2-G175R were reported to be nonfunctional channels unimpaired in their routing to the plasma membrane. In five families, seven novel AQP2 gene mutations were identified and their cell-biologic basis for causing recessive NDI was analyzed.

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Mutations in the aquaporin-2 gene (AQP2), encoding the vasopressin-regulated water channel of the renal collecting duct, are responsible for the autosomal recessive or dominant forms of congenital nephrogenic diabetes insipidus. We describe two new families with normal hypotensive and coagulation responses following the administration of desamino-8-D-arginine AVP, a clinical suggestion of normal vasopressin-2 receptors. The patients were compound heterozygotes for point mutations at nucleotide position 170 (CAG to CCG; Q57P) and at position 299 (GGA to GTA; G100V) in exon 1 of the AQP2 gene.

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Autosomal nephrogenic diabetes insipidus (NDI), a disease in which the kidney is unable to concentrate urine in response to vasopressin, is caused by mutations in the Aquaporin-2 (AQP2) gene. Analysis of a new family with dominant NDI revealed a single nucleotide deletion (727deltaG) in one AQP2 allele, which encoded an AQP2 mutant with an altered and extended C-terminal tail. When expressed in oocytes, the tetrameric AQP2-727deltaG was retained within the cell.

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The vasopressin-regulated water channel aquaporin-2 (AQP2) is known to tetramerize in the apical membrane of the renal tubular cells and contributes to urine concentration. We identified three novel mutations, each in a single allele of exon 4 of the AQP2 gene, in three families showing autosomal dominant nephrogenic diabetes insipidus (NDI). These mutations were found in the C-terminus of AQP2: a deletion of G at nucleotide 721 (721 delG), a deletion of 10 nucleotides starting at nucleotide 763 (763-772del), and a deletion of 7 nucleotides starting at nucleotide 812 (812-818del).

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Over 155 mutations within the V2 vasopressin receptor (AVPR2) gene are responsible for nephrogenic diabetes insipidus (NDI). The expression and subcellular distribution of four of these was investigated in transfected cells. These include a point mutation in the seventh transmembrane domain (S315R), a frameshift mutation in the third intracellular loop (804delG), and two nonsense mutations that code for AVPR2 truncated within the first cytoplasmic loop (W71X) and in the proximal portion of the carboxyl tail (R337X).

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X-linked nephrogenic diabetes insipidus (NDI) is a rare disease caused by mutations in the arginine vasopressin receptor 2 gene (AVPR2). Thirty-three novel AVPR2 mutations were identified in 62 families that were not included in our previous studies. This study describes the diversity of mutations observed in a total of 117 families, the number of affected people at the time of diagnosis, skewed X chromosome inactivation in severely affected females, the inferred parental origin of de novo mutations, and it provides estimates of incidence.

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