Next generation sequencing in family with MNGIE syndrome associated to optic atrophy: Novel homozygous POLG mutation in the C-terminal sub-domain leading to mtDNA depletion

Introduction Mitochondrial diseases are a group of disorders caused mainly by the impairment of the mitochondrial oxidative phosphorylation process, due to mutations either in the mitochondrial or nuclear genome. Among them, the mitochondrial neuro-gastrointestinal encephalo-myopathy (MNGIE) syndrome affects adolescents or young adults, and is mostly caused by TYMP mutations encoding a cytosolic thymidine phosphorylase (TP). Patients and methods The present study reports the molecular investigation by next-generation re-sequencing of 281 nuclear genes, encoding mitochondrial proteins, of consanguineous family including two individuals with MNGIE syndrome associated to optic atrophy. Bioinformatic analysis was also performed in addition to mtDNA deletion screening and mtDNA copy number quantification in blood of the two patients which were carried out by solf clipping program and qPCR respectively. Results Next-generation re-sequencing revealed a novel homozygous c.2391G > T POLG mutation (p.M797I) co-occurring with the hypomorphic c.1311A > G OPA1 variant (p.I437M). Analysis of the mitochondrial genome in the two patients disclosed mtDNA depletion in blood, but no deletion. Bio-informatics investigations supported the pathogenicity of the novel POLG mutation that is located in the C-terminal subdomain and might change POLG 3D structure, stability and function. Conclusion The novel homozygous p.M797I POLG mutation is responsible for MNGIE combined to optic atrophy and mtDNA depletion in the two patients

Magnetocaloric effect and critical behaviour of La0.5Ca0.2Ag0.3MnO3 compound

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FIXED POINT RESULTS FOR COUPLINGS ON ABSTRACT METRIC SPACES AND AN APPLICATION

WOS: 000432337500005Recently, Choudhury et al. [13] introduced the concept of couplings between two nonempty subsets in metric spaces. The aim of this paper is to prove the existence and uniqueness of strong coupled fixed points for a class of couplings in the context of cone metric spaces. Our results unify and generalize many know results in literature. Some examples are provided to illustrate the obtained results

Assessment of the critical behavior near the FM to PM phase transition in cubic Ni0.3−xCuxZn0.7Fe2O4 spinel ferrite

In this study, we report a thorough examination of the critical behavior of the cubic Ni0.3−xCux Zn0.7Fe2O4 (x = 0.0, 0.1 and 0.2) spinel ferrite which are crystallized with different irregular shapes of particle size (spherical,polygonal and cubic). The magnetic transition is ferromagnetic to paramagnetic state for all Cu-doped compounds. Different theoretical analyses, as the modified Arrott plot, Kouvel–Fisher method, and critical isotherm, have been used to identify the values of the ferromagnetic transition temperature TC, and the critical exponents of β, γ and δ. All the obtained values of critical parameters were found to be close to the 3D-Heisenberg theoretical model, which implies short-range magnetic interactions in Cu-doped compounds. The reliability of critical parameters was further checked through different methods, such as the Widom scaling relationship and the magnetic equation

Characteristics of some clay materials from Tamilnadu, India, and their possible ceramic uses Características de algumas argilas de Tamilnadu, India, e seus possíveis usos cerâmicos

X-ray fluorescence, themogravimetric-differential thermal analysis, Fourier Transform Infrared spectroscopy, X-ray diffraction, particle size analysis and Atterberg limits were used to study physico-chemical, mineralogical and thermal properties of two types of clays from four different locations of Tamilnadu, India. The chemical and mineralogical compositions of these clays differ considerably. The mineralogy indicated that the alluvial clays (G1 and G2) comprise highly quartz, illite, kaolinite, plagioclase and small amount of chlorite. The red clays (R1 and R2) were also rich in quartz, well-ordered kaolinite and abundant Fe-bearing minerals such as goethite and hematite. With respect to chemical composition, the G1 and G2 clays contained high amount of SiO2, low amount of Al2O3 and low loss on ignition, however, the R1 and R2 clays contain moderate amount of SiO2, Al2O3, and high amount of Fe2O3 and high loss on ignition. The results indicate that clays from alluvial deposit have adequate characteristics for common brick fabrication. However, clays collected from red clay deposit possessing adequate properties for roofing tile manufacturing and can be used for the manufacturing of common brick with some modification.<br>As técnicas de fluorescência de raios X, análise termogravimétrica-térmica diferencial, espectroscopia no infravermelho com transformada de Fourier, difração de raios X, análise de tamanho de partículas e limites de Atterberg foram utilizadas para o estudo de propriedades físico-químicas, mineralógicas e térmicas de dois tipos de argilas de quatro diferentes localizações em Tamilnadu, India. As composições químicas e mineralógicas dessas argilas diferem consideravelmente. A mineralogia indica que argilas aluviais (G1 and G2) são compostas principalmente de quartzo, ilita, caulinita, plagioclases e pequenas quantidades de cloretos. As argilas vermelhas (R1 and R2) são também ricas em quartzo, caulinita bem ordenada, e minerais abundantes em ferro tais como goetita e hematita. Com relação à composição química, as argilas G1 e G2 contém alto teor de SiO2, baixo teor de Al2O3 e baixa perda ao fogo; as argilas R1 e R2, entretanto, contém teor moderado de SiO2, Al2O3, e alto teor de Fe2O3 e alta perda ao fogo. Os resultados indicam que argilas de depósitos aluviais tem características adequadas para a fabricação de tijolos. Entretanto, as argilas coletadas de depósitos de argilas vermelhas com propriedades adequadas para fabricação de telhas podem ser utilizadas na fabricação de tijolos após algumas modificações