Hurler disease (mucopolysaccharidosis type IH): clinical features and consanguinity in Tunisian population

Mucopolysaccharidosis type I (MPS I) was a group of rare autosomal recessive disorder caused by the deficiency of the lysosomal enzyme, alpha -L -iduronidase, and the resulting accumulation of undergraded dematan sulfate and heparan sulfate. MPS I patients have a wide range of clinical presentations, that makes it difficult to predict patient phenotype which is needed for genetic counseling and also impedes the selection and evaluation of patients undergoing therapy bone marrow transplantation

Mucopolysaccharidosis type I: molecular characteristics of two novel alpha-L-iduronidase mutations in Tunisian patients

<p>Abstract</p> <p>Background</p> <p>Mucopolysaccharidosis type I (MPS I) is an autosomal storage disease resulting from defective activity of the enzyme α-L-iduronidase (IDUA). This glycosidase is involved in the degradation of heparan sulfate and dermatan sulfate. MPS I has severe and milder phenotypic subtypes.</p> <p>Aim of study: This study was carried out on six newly collected MPS I patients recruited from many regions of Tunisia.</p> <p>Patients and methods: Mutational analysis of the IDUA gene in unrelated MPS I families was performed by sequencing the exons and intron-exon junctions of IDUA gene.</p> <p>Results</p> <p>Two novel IDUA mutations, p.L530fs (1587_1588 insGC) in exon 11 and p.F177S in exon 5 and two previously reported mutations p.P533R and p.Y581X were detected. The patient in family 1 who has the Hurler phenotype was homozygous for the previously described nonsense mutation p.Y581X.</p> <p>The patient in family 2 who also has the Hurler phenotype was homozygous for the novel missense mutation p.F177S. The three patients in families 3, 5 and 6 were homozygous for the p.P533R mutation. The patient in family 4 was homozygous for the novel small insertion 1587_1588 insGC. In addition, eighteen known and one unknown IDUA polymorphisms were identified.</p> <p>Conclusion</p> <p>The identification of these mutations should facilitate prenatal diagnosis and counseling for MPS I in Tunisia.</p> <p>Background</p> <p>Mucopolysaccharidosis type I (MPS I) is an autosomal recessive lysosomal storage disorder caused by the deficient activity of the enzyme of α-L-iduronidase (IDUA, EC 3.2.1.76). This glycosidase is involved in the degradation of heparan sulfate and dermatan sulfate. The clinical phenotype of MPS I ranges from the very severe in Hurler syndrome (MPS IH) to the relatively benign in Scheie syndrome (MPS IS), with an intermediate phenotype designated Hurler/Scheie (MPS IH/S) <abbrgrp><abbr bid="B1">1</abbr></abbrgrp>. Isolation of complementary and genomic DNAs encoding human α -L- iduronidase <abbrgrp><abbr bid="B2">2</abbr><abbr bid="B3">3</abbr></abbrgrp> have enable the identification of mutations underlying the enzyme defect and resulting in MPS I clinical phenotype. More than 100 mutations have been reported in patients with the MPS I subtypes (Human Gene Mutation Database; <url>http://www.hgmd.org</url>). High prevalence of the common mutations p.W402X and p.Q70X has been described; both of them in the severe clinical forms <abbrgrp><abbr bid="B4">4</abbr><abbr bid="B5">5</abbr></abbrgrp>. A high prevalence of common mutation p.P533R has also been described in MPS I patients with various phenotypes <abbrgrp><abbr bid="B5">5</abbr><abbr bid="B6">6</abbr></abbrgrp>. In addition, rare mutations including single base substitution, deletion, insertion and splicing site mutation have been identified <abbrgrp><abbr bid="B7">7</abbr></abbrgrp>, indicating a high degree of allelic heterogeneity in IDUA gene.</p> <p>Here, we described two novel IDUA mutations in MPS I Tunisian patients. These lesions were homoallelic in all the patients of the six families investigated as consanguineous marriages are still frequent in Tunisia <abbrgrp><abbr bid="B8">8</abbr></abbrgrp>.</p

Bis(3-azoniapentane-1,5-diaminium) cyclohexaphosphate dihydrate: a monoclinic polymorph

In the title hydrated molecular salt, 2C4H16N33+&amp;#183;P6O186&amp;#8722;&amp;#183;2H2O, the complete cyclohexaphosphate anion is generated by crystallographic inversion symmetry. The six P atoms of the P6O186&amp;#8722; anion form a chair conformation and the organic cation has a corrugated linear geometry. In the crystal, the cations and the anions are connected by N&amp;#8212;H...O hydrogen bonds into slabs propagating in the ac plane. The water molecules link the slabs by accepting N&amp;#8212;H...O links and forming O&amp;#8212;H...O links. The triclinic polymorph was reported by Gharbi et al. [(1995). J. Solid State Chem. 114, 42&amp;#8211;51]

Crystal structure, quantum mechanical investigation, IR and NMR spectroscopy of two new organic perchlorates: (C6H18N3)·(ClO4)3H2O (I) and (C9H11N2)·ClO4(II)

The reaction of perchloric acid with 1-(2-aminoethyl)piperazine or 5,6-dimethyl-benzimidazole results in the formation of 1-(2-amonioethyl)piperazine-1,4-dium triperchlorate hydrate (C6H18N3)·(ClO4)3·H2O (I) or 5,6-dimethyl-benzylimidazolium perchlorate (C9H11N2)·ClO4(II). Both compounds were fully structurally characterized including single crystal X-ray diffraction analysis. Compound (I) crystallizes in the centrosymmetric triclinic space group P 1¯ with the lattice parameters a = 7.455 (2), b = 10.462 (2), c = 10.824 (2) Å, α = 80.832 (2), β = 88.243 (2), γ = 88.160 (2) °, Z = 2 and V = 832.77 (3) Å3. Compound (II) has been found to belong to the P21/c space group of the monoclinic system, with a = 7.590 (3), b = 9.266 (3), c = 16.503 (6) Å, β = 107.38 (2) °, V = 1107.69 (7) Å3and Z = 4. The structures of (I) and (II) consist of slightly distorted [ClO4]-tetrahedra anions and 1-(2-amonioethyl)piperazine-1,4-dium trication (I) or 5,6-dimethyl-benzylimidazolium cations (II) and additionally a lattice water in (I). The crystal structures of (I) and (II) exhibit complex three-dimensional networks of H-bonds connecting all their components. In the atomic arrangement of (I), the ClO4−anions form corrugated chains, while in (II) the atomic arrangement exhibits wide pseudo-hexagonal channels of ClO4tetrahedra including the organic entities. The lattice water serves as a link between pairs of cations and pairs of anions via several O–H⋯O and N-H⋯O interactions in compound (I). The vibrational absorption bands were identified by infrared spectroscopy. These compounds were also investigated by solid-state13C,35Cl and15N NMR spectroscopy. DFT calculations allowed the attribution of the IR and NMR bands. Intermolecular interactions were investigated by Hirshfeld surfaces. Electronic properties such as HOMO and LUMO energies were derived

Synthesis and Optical Properties of Graphene Quantum Dots

International audienceThe outstanding electronic, optical and mechanical properties of graphene strongly inspire the scientific community at both the fundamental and applicative levels. However, the key issue that needs to be addressed is the control and the modification of the electronic properties of graphene, and notably the opening of a sizable bandgap. For the last decade, a great attention has been paid to the size reduction of graphene using conventional top-down approaches (lithography and etching, thermal treatments and oxidation of bulk materials) to fabricate graphene quantum dots (GQDs) or graphene nanoribbons (GNRs). However, top-down approaches do not permit to manipulate the structure of the material at the atomic scale. In particular, they do not allow a sufficient control of the morphology and oxidation state of the edges, which drastically impact the properties. In order to truly control, with the required level of precision, the morphology and the composition of the materials and of its edges, the bottom-up approach is the relevant way to proceed. Recently, we reported on the synthesis and single photon emission properties of triangular-shaped GQDs. While, this initial report focused on functionalized nanoparticles, we now turn to non-functionalized graphene quantum dots that are in terms of structure closer to real graphene. Here, we described the synthesis, the dispersion and optical properties of a series of rod-shaped particles and we studied the structure-properties relationship in these graphene quantum dots. To this end, we designed a series of GQDs with a given edge type and by changing only one parameter (one dimension, namely the length or the width-Figure 1), we expect to follow simply the evolution of the optical properties

Crystal structure, Hirshfeld surface analysis, thermal behavior and spectroscopic investigations of a new organic cyclohexaphosphate, (C 10 H 15 N 2 ) 4 (Li) 2 (P 6 O 18 )(H 2 O) 6

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Synthesis, structural characterisations, NMR spectroscopy, Hirshfeld surface analysis and electrochemical study of a new organic cyclohexaphosphate, (C6H7FN)4(Li)2(P6O18) (H2O)6

(C6H7FN)4(Li)2(P6O18) (H2O)6(I), a new organic cyclohexaphosphate, has been synthesized and grown at room temperature by an acid/base reaction between H6P6O18and 2-fluoroaniline as an organic template. The crystal structure of (I) was solved by single crystal X-ray diffraction analysis and it was found that the material belongs to triclinic system with space group P-1 and refined R-factor of 0.0520. Adjacent P6O18rings are connected via corner-sharing by LiO4tetrahedra, generating anionic [Li2P6O18·H2O]4-layers parallel to the (a, b) plane. The 2-fluoro-anilinium cations are inserted in the interlayer space and interact with the inorganic framework through N–H⋯O and O–H⋯O hydrogen-bonding interactions. Additional stabilization is provided by strong N–H⋯F and weak C–H⋯O hydrogen bonds. Hirshfeld surface analysis reveals the nature of intermolecular contacts of the title compound and their enrichment ratio reveals if they are over-represented. The crystal packing is a combination of strong electrostatic attractive interactions and of weaker hydrophobic contacts. The title compound was further characterized by FT-IR and NMR spectroscopies. Crystal symmetry is confirmed by31P magic angle spinning NMR and the vibrational absorption bands were identified by infrared spectroscopy. Electrical conductivity was studied using impedance spectroscopy and results showed that the conductivity at 150 °C was equal to 4.93 × 10−4S cm−1. It is therefore concluded that (C6H7FN)4(Li)2(P6O18) (H2O)6can be further used in lithium batteries