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1.
Rev. neurol. (Ed. impr.) ; 78(7): 179-183, Ene-Jun, 2024. mapas, tab
Artigo em Espanhol | IBECS | ID: ibc-232185

RESUMO

Introducción: Las miopatías relacionadas con el receptor de rianodina de tipo 1 (RYR1-RM) constituyen la categoría más frecuente de miopatías congénitas. La introducción de técnicas genéticas ha cambiado el paradigma diagnóstico y sugiere la prioridad de estudios moleculares sobre biopsias. Este estudio busca explorar las características clinicoepidemiológicas de pacientes con variantes del gen RYR1 en un hospital pediátrico de tercer nivel con el objetivo de ampliar la comprensión de la correlación genotipo-fenotipo en las RYR1-RM. Pacientes y métodos: Estudio observacional, descriptivo y transversal, de pacientes menores de 14 años con síntomas miopáticos y variantes potencialmente patógenas del gen RYR1 entre enero de 2013 y diciembre de 2023, considerando variables como sexo, edad, desarrollo motor, variantes genéticas, patrón de herencia y otras manifestaciones. Todas las variables fueron tabuladas frente a la variante genética. Resultados: De los nueve pacientes incluidos, la incidencia estimada fue de aproximadamente 1/10.000 nacidos vivos. La mediana en el momento del diagnóstico fue de 6 años, con una variabilidad fenotípica significativa. Se observaron síntomas comunes, como debilidad y retraso del desarrollo motor. Las variantes genéticas afectaron al gen RYR1 de manera diversa, y hubo cinco variantes previamente no descritas. La biopsia muscular se realizó en cinco pacientes, en dos de ellos de tipo miopatía central core; en uno, multiminicore; en uno, desproporción congénita de fibras; y en otro, de patrón inespecífico. Conclusiones: Las RYR1-MR de nuestra serie ofrecieron variabilidad fenotípica y de afectación, con una incidencia en nuestra área de en torno a 1/10.000 recién nacidos. La mayoría de los casos fueron varones, de variantes missense dominantes. Aportamos cinco variantes genéticas no descritas con anterioridad.(AU)


Introduction: Ryanodine receptor type 1-related myopathies (RYR1-RM) represent the most prevalent category of congenital myopathies. The introduction of genetic techniques has shifted the diagnostic paradigm, suggesting the prioritization of molecular studies over biopsies. This study aims to explore the clinical and epidemiological characteristics of patients with RYR1 gene variants in a tertiary pediatric hospital, intending to enhance the understanding of the genotype-phenotype correlation in RYR1-RM. Patients and methods: An observational, descriptive, and cross-sectional study was conducted on patients under 14 years old with myopathic symptoms and potentially pathogenic RYR1 gene variants from January 2013 to December 2023. Variables such as gender, age, motor development, genetic variants, inheritance pattern, and other manifestations were considered. All variables were tabulated against the genetic variant. Results: Of the nine included patients, the estimated incidence was approximately 1 in 10,000 live births. The median age at diagnosis was six years, with significant phenotypic variability. Common symptoms such as weakness and delayed motor development were observed. Genetic variants affected the RYR1 gene diversely, including five previously undescribed variants. Muscle biopsy was performed in five patients, revealing central core myopathy in two, multiminicore in one, congenital fiber-type disproportion in one, and a nonspecific pattern in another.(AU)


Assuntos
Humanos , Masculino , Feminino , Criança , Doenças Musculares/classificação , Canal de Liberação de Cálcio do Receptor de Rianodina , Incidência , Padrões de Herança , Epidemiologia Descritiva , Estudos Transversais , Estudos de Associação Genética
2.
Rev Neurol ; 78(7): 179-183, 2024 Apr 01.
Artigo em Espanhol | MEDLINE | ID: mdl-38502166

RESUMO

INTRODUCTION: Ryanodine receptor type 1-related myopathies (RYR1-RM) represent the most prevalent category of congenital myopathies. The introduction of genetic techniques has shifted the diagnostic paradigm, suggesting the prioritization of molecular studies over biopsies. This study aims to explore the clinical and epidemiological characteristics of patients with RYR1 gene variants in a tertiary pediatric hospital, intending to enhance the understanding of the genotype-phenotype correlation in RYR1-RM. PATIENTS AND METHODS: An observational, descriptive, and cross-sectional study was conducted on patients under 14 years old with myopathic symptoms and potentially pathogenic RYR1 gene variants from January 2013 to December 2023. Variables such as gender, age, motor development, genetic variants, inheritance pattern, and other manifestations were considered. All variables were tabulated against the genetic variant. RESULTS: Of the nine included patients, the estimated incidence was approximately 1 in 10,000 live births. The median age at diagnosis was six years, with significant phenotypic variability. Common symptoms such as weakness and delayed motor development were observed. Genetic variants affected the RYR1 gene diversely, including five previously undescribed variants. Muscle biopsy was performed in five patients, revealing central core myopathy in two, multiminicore in one, congenital fiber-type disproportion in one, and a nonspecific pattern in another. CONCLUSIONS: RYR1-RM in our series exhibited phenotypic and involvement variability, with an incidence in our area of around 1 in 10,000 live births. Most cases were male, with dominant missense variants. We contribute five previously undescribed genetic variants.


TITLE: Miopatías RYR1 en la infancia: correlación fenotipo-genotipo e incidencia.Introducción. Las miopatías relacionadas con el receptor de rianodina de tipo 1 (RYR1-RM) constituyen la categoría más frecuente de miopatías congénitas. La introducción de técnicas genéticas ha cambiado el paradigma diagnóstico y sugiere la prioridad de estudios moleculares sobre biopsias. Este estudio busca explorar las características clinicoepidemiológicas de pacientes con variantes del gen RYR1 en un hospital pediátrico de tercer nivel con el objetivo de ampliar la comprensión de la correlación genotipo-fenotipo en las RYR1-RM. Pacientes y métodos. Estudio observacional, descriptivo y transversal, de pacientes menores de 14 años con síntomas miopáticos y variantes potencialmente patógenas del gen RYR1 entre enero de 2013 y diciembre de 2023, considerando variables como sexo, edad, desarrollo motor, variantes genéticas, patrón de herencia y otras manifestaciones. Todas las variables fueron tabuladas frente a la variante genética. Resultados. De los nueve pacientes incluidos, la incidencia estimada fue de aproximadamente 1/10.000 nacidos vivos. La mediana en el momento del diagnóstico fue de 6 años, con una variabilidad fenotípica significativa. Se observaron síntomas comunes, como debilidad y retraso del desarrollo motor. Las variantes genéticas afectaron al gen RYR1 de manera diversa, y hubo cinco variantes previamente no descritas. La biopsia muscular se realizó en cinco pacientes, en dos de ellos de tipo miopatía central core; en uno, multiminicore; en uno, desproporción congénita de fibras; y en otro, de patrón inespecífico. Conclusiones. Las RYR1-MR de nuestra serie ofrecieron variabilidad fenotípica y de afectación, con una incidencia en nuestra área de en torno a 1/10.000 recién nacidos. La mayoría de los casos fueron varones, de variantes missense dominantes. Aportamos cinco variantes genéticas no descritas con anterioridad.


Assuntos
Doenças Musculares , Canal de Liberação de Cálcio do Receptor de Rianodina , Humanos , Masculino , Criança , Adolescente , Feminino , Canal de Liberação de Cálcio do Receptor de Rianodina/genética , Estudos Transversais , Incidência , Doenças Musculares/epidemiologia , Doenças Musculares/genética , Estudos de Associação Genética , Fenótipo , Genótipo
3.
Talanta ; 207: 120275, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31594592

RESUMO

The magnetic metal-organic framework Fe3O4@(Fe-(benzene-1,3,5-tricarboxylic acid) (MMOF) was prepared, characterized and studied as a magnetic sorbent for the dispersive solid-phase extraction (DSPE) of several widely used blood lipid regulators (i.e., bezafibrate, clofibric acid, clofibrate, gemfibrozil and fenofibrate) from water samples. Characterization of the synthesized Fe3O4@Fe-BTC magnetic nanomaterial was performed by Fourier transform infrared spectroscopy, powder X-ray diffractometry, thermogravimetric analysis, scanning electron microscopy and transmission electron microscopy. The magnetic nanocomposite was found to be chemically stable and to possess a large surface area (803.62 m2/g) and pore volume (0.59 cm³/g). The concentrations of fibrates in different water samples were determined using HPLC-UV-Vis and confirmed by UPLC-MS/MS. Parameters affecting the extraction efficiency of magnetic-DSPE were studied and optimized. The maxima absorption capacities (Qmax) were determined to be (in mg/g) 197.0 for bezafibrate, 620.3 for clofibric acid, 537.6 for clofibrate, 288.7 gemfibrozil and 223.2 for fenofibrate. Validations of the optimized magnetic DSPE method for analyses at two fibrate concentrations in spiked water samples produced relative recovery values ≤ 70% for clofibrate and within the range of 80-100% for bezafibrate, clofibric acid, gemfibrozil and fenofibrate. LODs ranging from 4 µg/L for fenofibrate to 99 µg/L for gemfibrozil were obtained. The validated methodology produced recovery values ranging from 70 to 112% (relative standard deviations < 7%).


Assuntos
Benzeno/química , Ferro/química , Reguladores do Metabolismo de Lipídeos/isolamento & purificação , Estruturas Metalorgânicas/química , Extração em Fase Sólida/métodos , Ácidos Tricarboxílicos/química , Água/química , Reguladores do Metabolismo de Lipídeos/sangue , Nanopartículas de Magnetita/química , Poluentes Químicos da Água/isolamento & purificação
4.
Chem Sci ; 8(5): 3694-3702, 2017 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-28580105

RESUMO

A vast impact on molecular nanoscience can be achieved using simple transition metal complexes as dynamic chemical systems to perform specific and selective tasks under the control of an external stimulus that switches "ON" and "OFF" their electronic properties. While the interest in single-ion magnets (SIMs) lies in their potential applications in information storage and quantum computing, the switching of their slow magnetic relaxation associated with host-guest processes is insufficiently explored. Herein, we report a unique example of a mononuclear cobalt(ii) complex in which geometrical constraints are the cause of easy and reversible water coordination and its release. As a result, a reversible and selective colour and SIM behaviour switch occurs between a "slow-relaxing" deep red anhydrous material (compound 1) and its "fast-relaxing" orange hydrated form (compound 2). The combination of this optical and magnetic switching in this new class of vapochromic and thermochromic SIMs offers fascinating possibilities for designing multifunctional molecular materials.

5.
Chemosphere ; 150: 659-666, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26879292

RESUMO

Silver nanoparticles (AgNP) are emerging pollutants. The use of novel materials such as Cu-(benzene 1,3,5-tricarboxylate, BTC) Metal-Organic Framework (MOFs), for AgNP adsorption and their removal from aqueous solutions has been studied. The effect of different parameters was followed and isotherm model was suggested. MOFs adsorbed fast and efficiently AgNP in the range C0 < 10 mg L(-1), being Freundlich isotherm (R = 0.993) these data fitted to. Among studied parameters a remarkable effect of chloride on sorption was found, thus their possible interactions were considered. The high adsorption efficiency of AgNP was achieved and it was found to be very fast. The feasibility of adsorption on Cu-(BTC) was proved in spiked waters. The results showed the potential interest of new material as adsorbent for removing AgNP from environment.


Assuntos
Cobre/química , Nanopartículas Metálicas/análise , Compostos Organometálicos/química , Prata/análise , Poluentes Químicos da Água/análise , Purificação da Água/métodos , Adsorção , Coloides , Estruturas Metalorgânicas
6.
Dalton Trans ; (12): 1583-96, 2008 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-18335142

RESUMO

The preparation, crystal structures and magnetic properties of the copper(II) complexes of formula [Cu(pyim)(tcm)(2)](n) (1), [Cu(bpy)(tcm)(2)](n) (2), [Cu(4)(bpz)(4)(tcm)(8)] (3), {[Cu(terpy)(tcm)].tcm}(n) (4) and {[Cu(2)(tppz)(tcm)(4)].3/2H(2)O}(n) (5) [pyim = 2-(2-pyridyl)imidazole, tcm = tricyanomethanide, bpy = 2,2'-bipyridine, bpz = 2,2'-bipyrazine, terpy = 2,2':6',2''-terpyridine and tppz = 2,3,5,6-tetrakis(2-pyridyl)pyrazine] are reported. Complexes, 1, 2 and 4 are uniform copper(II) chains with single- (1 and 4) and double-(2) micro-1,5-tcm bridges with values of the intrachain copper-copper separation of 7.489(1) (1), 7.520(1) and 7.758(1) (2) and 7.469(1) A (4). Each copper atom in 1, 2 and 4 is five-coordinate with bidentate pyim (1)/bpy (2) and tridentate terpy (4) ligands and nitrile-nitrogen atoms from bridging (1,2 and 4) and terminal (1) tcm groups building a distorted square pyramidal surrounding. The structure of 3 is made up of neutral centrosymmetric rectangles of (2,2'-bipyrazine)copper(II) units at the corners, the edges being built by single- and double-micro-1,5-tcm bridges with copper-copper separations of 7.969(1) and 7.270(1) A, respectively. Five- and six-coordinated copper atoms with distorted square pyramidal and elongated octahedral environments occur in . Compound 5 is a neutral copper(II) chain with regular alternating bis-tridentate tppz and double micro-1,5-tcm bridges, the intrachain copper-copper distances being 6.549(7) and 7.668(1) A, respectively. The two crystallographically independent copper atoms in 5 have an elongated octahedral geometry with three tppz nitrogen atoms and a nitrile-nitrogen atom from a bridging tcm group in the equatorial positions, and two nitrile nitrogen atoms from a terminal and a bridging tcm ligand occupying the axial sites. The investigation of the magnetic properies of 1-5 in the temperature range 1.9-295 K has shown the occurrence of weak ferro- [J = +0.11(1) cm(-1) (2)] and antiferromagnetic interactions [J = -0.093(1) (1), -0.083(1) (4), -0.04(1) and 1.21(1) cm(-1) (3)] across the micro-1,5-tcm bridges and intermediate antiferromagnetic coupling [-J = 37.4(1) cm(-1) (5)] through bis-tridentate tppz. The values of the magnetic interactions are analyzed through simple orbital symmetry considerations and compared with those previously reported for related systems.

7.
Acta Crystallogr C ; 62(Pt 10): o599-601, 2006 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17008747

RESUMO

In the title compound, C15H20N2O, the bond distances and angles are consistent with the presence of the hydroxy tautomer. This tautomer was unambiguously determined by the clear presence of a H atom bonded to oxygen, as well as the total absence of any residual electron density around the N atom in the heterocycle, thus precluding any possibility of desmotropism.

8.
Inorg Chem ; 39(17): 3845-52, 2000 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-11196779

RESUMO

Two polymorphic malonato-bridged copper(II) complexes of formula ([Cu(bpy)(H2O)][Cu(bpy)(mal)(H2O)])-(ClO4)2 (1 and 2) (bpy = 2,2'-bipyridine and mal = malonate dianion) have been prepared and their structures solved by X-ray diffraction methods. Compound 1 crystallizes in the monoclinic space group P2(1)/a, with a = 23.743(3) A, b = 9.7522(5) A, c = 27.731(2) A, beta = 114.580(10) degrees, and Z = 4. Compound 2 crystallizes in the orthorhombic space group Pbcn, with a = 23.700(5) A, b = 25.162(5) A, c = 9.693(5) A, and Z = 4. The structures of 1 and 2 are made up of uncoordinated perchlorate anions and malonate-bridged zigzag copper(II) chains grouped in an isosceles triangle running parallel to the b (1) and c (2) axes. These chains are built by a [Cu(bpy)(mal)(H2O)] unit acting as bis-monodentate ligand toward two [Cu(bpy)(H2O)] adjacent units through its OCCCO skeleton in an anti-anti conformation, whereas the OCO carboxylate bridges exhibit the anti-syn conformation. Compounds 1 and 2 contain four crystallographically independent copper(II) atoms, but the environment of all of them is distorted square pyramidal: the axial position is occupied by a water molecule, whereas the equatorial plane is formed by a chelating bpy and either a bidentate malonate or two carboxylate oxygens from two malonate groups. The equatorial Cu-O(mal) (1.911(4)-1.978(4) (1) and 1.897(5)-1.991(4) A (2)) and Cu-N(bpy) (1.983(4)-2.008(5) (1) and 1.971(6)-2.007(6) A (2)) bonds are somewhat shorter than the axial Cu-O(w) one (2.257(5)-2.524(5) (1) and 2.236(5)-2.505(6) A (2)). The angles subtended at the copper atom by the chelating bpy vary in the ranges 80.9(2)-81.8(2) degrees (1) and 80.4(2)-82.1(2) degrees (2), values which are somewhat smaller than those of the chelating malonate (80.4(2)-82.1(2) degrees (1) and 93.0(2)-93.6(2) degrees (2)). The intrachain copper-copper separations through the OCCCO fragment are 8.227(1) (1) and 8.206(2) A (2), whereas those through the OCO bridging unit are 4.579(1)-5.043(1) (1) and 4.572(2)-5.040(2) A (2). The magnetic behavior of 1 and 2 in the temperature range 2.0-290 K is very close, and it corresponds to an overall ferromagnetic coupling, the chi MT versus T curve exhibiting a maximum at 18 K. The analysis of the magnetic data through a numerical expression derived for the real topology of 1 and 2, that is, chains of isosceles triangles with two intrachain exchange pathways J1 (exchange coupling through the OCO carboxylate) and J2 (exchange coupling through the OCCCO malonate), indicates the occurrence of ferro- (J1 = +4.6 cm-1) and antiferromagnetic couplings (J2 = -4.2 cm-1). The magnetic coupling through these exchange pathways is further analyzed and substantiated by density functional theory calculations on a malonate-bridged trinuclear copper(II) model system.

9.
Inorg Chem ; 39(7): 1363-70, 2000 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-12526437

RESUMO

Three malonato-bridged copper(II) complexes of the formulas [[Cu(H2O)3][Cu(C3H2O4)2(H2O)]]n (1), [[Cu(H2O)4]2[Cu(C3H2O4)2(H2O)]] [Cu(C3H2O4)2(H2O)2][[Cu(H2O)4][Cu(C3H2O4)2(H2O)2]] (2), and [Cu(H2O)4][Cu(C3H2O4)2(H2O)2] (3) (C3H2O4 = malonate dianion) have been prepared, and the structures of the two former have been solved by X-ray diffraction methods. The structure of compound 3 was already known. Complex 1 crystallizes in the orthorhombic space group Pcab, Z = 8, with unit cell parameters of a = 10.339(1) A, b = 13.222(2) A, and c = 17.394(4) A. Complex 2 crystallizes in the monoclinic space group P2/c, Z = 4, with unit cell parameters of a = 21.100(4) A, b = 21.088(4) A, c = 14.007(2) A, and beta = 115.93(2) degrees. Complex 1 is a chain compound with a regular alternation of aquabis(malonato)copper(II) and triaquacopper(II) units developing along the z axis. The aquabis(malonato)copper(II) unit acts as a bridging ligand through two slightly different trans-carboxylato groups exhibiting an anti-syn coordination mode. The four carboxylate oxygens, in the basal plane, and the one water molecule, in the apical position, describe a distorted square pyramid around Cu1, whereas the same metal surroundings are observed around Cu2 but with three water molecules and one carboxylate oxygen building the equatorial plane and a carboxylate oxygen from another malonato filling the apical site. Complex 2 is made up of discrete mono-, di-, and trinuclear copper(II) complexes of the formulas [Cu(C3H2O4)2(H2O)2]2-, [[Cu(H2O)4] [Cu(C3H2O4)2(H2O)2]], and [[Cu(H2O)4]2[Cu(C3H2O4)2(H2O)]]2+, respectively, which coexist in a single crystal. The copper environment in the mononuclear unit is that of an elongated octahedron with four carboxylate oxygens building the equatorial plane and two water molecules assuming the axial positions. The neutral dinuclear unit contains two types of copper atoms, one that is six-coordinated, as in the mononuclear entity, and another that is distorted square pyramidal with four water molecules building the basal plane and a carboxylate oxygen in the apical position. The overall structure of this dinuclear entity is nearly identical to that of compound 3. Finally, the cationic trimer consists of an aquabis(malonato)copper(II) complex that acts as a bismonodentate ligand through two cis-carboxylato groups (anti-syn coordination mode) toward two tetraaqua-copper(II) terminal units. The environment of the copper atoms is distorted square pyramidal with four carboxylate oxygens (four water molecules) building the basal plane of the central (terminal) copper atom and a water molecule (a carboxylate oxygen) filling the axial position. The magnetic properties of 1-3 have been investigated in the temperature range 1.9-290 K. Overall, ferromagnetic behavior is observed in the three cases: two weak, alternating intrachain ferromagnetic interactions (J = 3.0 cm-1 and alpha J = 1.9 cm-1 with H = -J sigma i[S2i.S2i-1 + alpha S2i.S2i+1]) occur in 1, whereas the magnetic behavior of 2 is the sum of a magnetically isolated spin doublet and ferromagnetically coupled di- (J3 = 1.8 cm-1 from the magnetic study of the model complex 3) and trinuclear (J = 1.2 cm-1 with H = -J (S1.S2 + S1.S3) copper(II) units. The exchange pathway that accounts for the ferromagnetic coupling, through an anti-syn carboxylato bridge, is discussed in the light of the available magneto-structural data.

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