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1.
Luminescence ; 35(2): 250-259, 2020 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-31749285

RESUMEN

Four core-shell structured nanometre luminescent composites with different kernel sizes and different shell layer thicknesses (SiO2(500) @Eu (phen-Si)(50) , SiO2(500) @Eu (phen-Si)(15) , SiO2(250) @Eu (phen-Si)(5) and SiO2(250) @Eu (phen-Si)(10) ) were made by changing synthesis conditions. Here, initial subscript numbers in parentheses refer to the particle size of the SiO2 core, whereas the final subscript numbers in parentheses refer to shell layer thickness. In these composites, silica spheres of 500 nm or 250 nm were identified as the core. The shell layer was composited of silicon, 1,10-phenanthroline and europium perchlorate, abbreviated as Eu(phen-Si); the chemical formula of phen-Si was phen-N-(CONH (CH2 )Si(OCH2 CH3 )3 )2 . The composites were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), and infrared spectroscopy. The monodispersed spherical SiO2 showed characteristics of a regular microstructure and a smooth surface, as well as the advantage of dispersity, shown by SEM. The Eu(phen-Si) complex was able to self-assemble into monodispersed SiO2 spheres, as seen using TEM. Fluorescence spectra indicated that the four composites had excellent luminescence properties. Furthermore, composites composed of a SiO2 core and a 250 nm kernel size exhibited stronger fluorescence than 500 nm kernel-sized composites. Fluorescence properties were affected by shell thickness: the thicker the shell, the greater the fluorescence intensity. For the four composites, quantum yield values and fluorescence lifetime corresponded to fluorescence emission intensity data as quantum yield values and fluorescence lifetime were higher, and luminescence properties increased.


Asunto(s)
Complejos de Coordinación/química , Europio/química , Sustancias Luminiscentes/química , Nanosferas/química , Compuestos de Organosilicio/química , Dióxido de Silicio/química , Complejos de Coordinación/síntesis química , Sustancias Luminiscentes/síntesis química , Estructura Molecular , Tamaño de la Partícula , Propiedades de Superficie
3.
Luminescence ; 29(7): 791-7, 2014 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-24395674

RESUMEN

A novel ternary complex, Tb(2)L4 · L'·(ClO4)6 · 8H2O, has been synthesized using bis(benzylsulfinyl)methane as the first ligand L and 2,2'-dipyridyl as the second ligand L'. The ternary complex was characterized by element analysis, molar conductivity, coordination titration analysis, infrared, thermogravimetric-differential scanning calorimetric and ultraviolet spectra. The results indicated that the composition of the complex was Tb2 L4 · L'·(ClO4)6 · 8H2O (L = C(6)H(5)CH(2) SOCH(2)SOCH(2)C(6)H(5); L' = Dipy). Fourier transform infrared results revealed that the perchlorate group was bonded with the Tb(III) ion by the oxygen atom, and the coordination was bidentate. The fluorescent spectra illustrated that the complex displayed characteristic fluorescence in the solid state. After the introduction of the second ligand, 2,2-dipyridyl, the relative emission intensity and fluorescence lifetime of the ternary complex Tb(2)L(4) · L'·(ClO(4))(6) · 8H2O were enhanced compared to the binary complex TbL(2.5)(ClO4)3 · 3H2O. This indicated that the presence of both organic ligand bis(benzylsulfinyl)methane and the second ligand 2,2-dipyridyl could sensitize the fluorescence intensity of Tb(III) ion, and introduction of the 2,2-dipyridyl group resulted in an enhancement of the fluorescence of the Tb(III) ternary rare earth complex. The strongest characteristic fluorescence emission intensity of the ternary complex was 9.36 times that of the binary complex. The phosphorescence spectra and fluorescence lifetime of the complex were also measured.


Asunto(s)
2,2'-Dipiridil/química , Complejos de Coordinación/química , Luminiscencia , Percloratos/química , Terbio/química , Complejos de Coordinación/síntesis química
4.
Luminescence ; 29(7): 810-7, 2014 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-24436058

RESUMEN

A novel ligand, 1-(naphthalen-2-yl)-2-(phenylsulthio)ethanone was synthesized using a new method and its two europium (Eu) (III) complexes were synthesized. The compounds were characterized by elemental analysis, coordination titration analysis, molar conductivity, infrared, thermo gravimetric analyzer-differential scanning calorimetry (TGA-DSC), (1)H NMR and UV spectra. The composition was suggested as EuL5 · (ClO4)3 · 2H2O and EuL4 · phen(ClO4)3 · 2H2O (L = C(10)H(7)COCH(2)SOC(6)H(5)). The fluorescence spectra showed that the Eu(III) displayed strong characteristic metal-centered fluorescence in the solid state. The ternary rare earth complex showed stronger fluorescence intensity than the binary rare earth complex in such material. The strongest characteristic fluorescence emission intensity of the ternary system was 1.49 times as strong as that of the binary system. The phosphorescence spectra were also discussed.


Asunto(s)
Complejos de Coordinación/química , Europio/química , Luminiscencia , Fenantrolinas/química , Complejos de Coordinación/síntesis química , Ligandos , Estructura Molecular
5.
Luminescence ; 28(3): 302-7, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-22736601

RESUMEN

A novel ligand containing multiple coordinating groups (sulfinyl, carboxyl and carbonyl groups), acetophenonylcarboxymethyl sulphoxide, was synthesized. Its corresponding two lanthanide (III) binary complexes were synthesized and characterized by element analysis, molar conductivity, FT-IR, TG-DTA and UV spectroscopy. Results showed that the composition of these complexes was REL3 L(-) (ClO4)2 · 3H2O (RE = Eu (III), Tb (III); L = C6 H5 COCH2 SOCH2 COOH; L(-) = C6H5 COCH2 SOCH2 COO(-)). FT-IR results indicated that acetophenonylcarboxymethyl sulphoxide was bonded with an RE (III) ion by an oxygen atom of the sulfinyl and carboxyl groups and not by an oxygen atom of the carbonyl group due to high steric hinderance. Fluorescent spectra showed that the Tb (III) complex had excellent luminescence as a result of a transfer of energy from the ligand to the excitation state energy level ((5)D4) of Tb (III). The Eu (III) complex displayed weak luminescence, attributed to low energy transfer efficiency between the triplet state energy level of its ligand and the excited state ((5)D0 ) of Eu (III). As a result, the Tb (III) complex displayed a good antenna effect for luminescence. The fluorescence decay curves of Eu (III) and Tb (III) complexes were also measured.


Asunto(s)
Colorantes Fluorescentes/química , Elementos de la Serie de los Lantanoides/química , Sulfóxidos/química , Fluorescencia , Colorantes Fluorescentes/síntesis química , Estructura Molecular , Espectroscopía Infrarroja por Transformada de Fourier
6.
World J Clin Cases ; 10(17): 5770-5775, 2022 Jun 16.
Artículo en Inglés | MEDLINE | ID: mdl-35979113

RESUMEN

BACKGROUND: No known case of neuroendocrine tumour (NET) with schwannoma has been reported. CASE SUMMARY: A 63-year-old female presented to our hospital with nausea and vomiting. Upper gastrointestinal endoscopy revealed a mass in the descending part of the duodenum. Using ultrasound gastroscopy, we found that the tumour originated from the submucosa and showed low echo. We removed the tumour by electrocoagulation and sent it for pathological biopsy. CONCLUSION: Immunohistochemical results showed that the mass was a rare NET with neurilemmoma.

7.
Front Neurol ; 13: 790082, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35197922

RESUMEN

Mutations in the valosin-containing protein (VCP) gene have been linked to amyotrophic lateral sclerosis (ALS) in the Caucasian populations. However, the phenotype of VCP mutations in Chinese patients with (ALS) remains unclear. Targeted next-generation sequencing covered 28 ALS-related genes including the VCP gene was undertaken to screen in a Chinese cohort of 275 sporadic ALS cases and 15 familial ALS pedigrees. An extensive literature review was performed to identify all patients with ALS carrying VCP mutations previously reported. The clinical characteristics and genetic features of ALS patients with VCP mutations were reviewed. One known p.R155C mutation in the VCP gene was detected in two siblings from a familial ALS pedigree and two sporadic individuals. In addition, the same VCP p.R155C mutation was detected in an additional patient with ALS referred in 2021. Three patients with VCP p.R155C mutation presented with muscular weakness starting from proximal extremities to distal extremities. The other patient developed a phenotype of Paget's disease of bone in addition to the progressive muscular atrophy. We reported the first VCP mutation carrier manifesting ALS with Paget's disease of bone in the Chinese population. Our findings expand the phenotypic spectrum of the VCP mutations in Chinese patients with ALS and suggest that ALS patients with VCP p.R155C mutations tend to present with relatively young onset, symmetrical involvement of proximal muscles weakness of arms or legs, and then progressed to distal muscles of limbs.

8.
Front Mol Neurosci ; 15: 691534, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35283724

RESUMEN

TANK-binding kinase 1 (TBK1) has been identified as a causative gene of amyotrophic lateral sclerosis (ALS) in the Caucasian population in 2015. Here, we sequenced for TBK1 variants in a cohort of 15 familial ALS (fALS) and 275 sporadic ALS (sALS) of Chinese origin by targeted next-generation sequencing. We identified one likely benign missense variant (p. Ser398Pro), two missense variants of uncertain significance (p. Ile37Leu and p. Tyr677Asn), and two novel heterozygous variants in introns of TBK1, c.1522-3T > G and c.2066 + 4A > G. We performed splicing assays through minigene plasmids and RNA pull-down assay to determine that the two substitutions of nucleotides disrupted the binding of the important splicing regulator hnRNPA1 and promoted aberrant pre-mRNA splicing modes. The c.1522-3T > G variant promoted nearly 50.0% of abnormal transcripts (3 different types of insertions and deletions (indels) in junction of intron 13-exon 14) and the c.2066 + 4A > G variant inhibited about 75.0% inclusion of exon 19, both causing premature stop codon and producing TBK1 protein without CCD2. Immunofluorescence analysis showed that the expression of TBK1 with intronic variants was lower since less TBK1 distribution was observed in HEK293T cells. Both patients carrying TBK1 c.1522-3T > G and c.2066 + 4A > G variants developed a rapidly progressive ALS, with a survival of 31 and 10 months, respectively. The frequency of loss of function (LoF) variants in TBK1 was 0.73% in sALS in our cohort. We emphasize that intronic sequencing and pre-mRNA splicing analysis cannot be ignored to demonstrate the complex mutational spectrum and pathogenesis of ALS.

9.
J Clin Neurol ; 18(1): 41-47, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-35021275

RESUMEN

BACKGROUND AND PURPOSE: Mutations in the FIG4 gene have been linked to amyotrophic lateral sclerosis (ALS) type 11 in Caucasian populations. The purpose of this study was to identify FIG4 variants in a cohort of 15 familial ALS (FALS) indexes and 275 sporadic ALS (SALS) patients of Han Chinese origin. METHODS: All 23 exons of FIG4 were sequenced using targeted next-generation sequencing. An extensive literature review was performed to detect genotype-phenotype associations of FIG4 mutations. RESULTS: No FIG4 variants were identified in the FALS patients. One novel heterozygous missense variant (c.352G>T [p.D118Y]) and one novel heterozygous nonsense variant (c.2158G>T [p.E720X]) in FIG4 were identified in two SALS patients. The p.E720X variant is interpreted as likely pathogenic while the p.D118Y variant is a variant of uncertain significance. The patient carrying the p.E720X mutation developed lower-limb-onset slowly progressive ALS, and survived for 11.5 years. The patient harboring the FIG4 p.D118Y variant also presented with progressive ALS, with the score on the ALS Functional Rating Scale-Revised (ALSFRS-R) decreasing by 0.4 per month. The rate of decrease in the ALSFRS-R scores from symptom onset to diagnosis seemed to be lower in the patients carrying FIG4 variants than the no-FIG4-mutation ALS patients in this study. CONCLUSIONS: Our findings suggest that ALS patients carrying FIG4 mutations are not common in the Chinese population and are more likely to exhibit slow progression.

10.
Artículo en Inglés | MEDLINE | ID: mdl-32720527

RESUMEN

FUS gene is one of the most common mutated genes in amyotrophic lateral sclerosis (ALS). We sequenced for FUS mutations in a cohort of 15 familial ALS and 275 sporadic ALS of Chinese origin. All 15 exons of the FUS gene were sequenced by targeted next-generation sequencing in a cohort of 15 familial ALS indexes and 275 sporadic ALS patients of Chinese origin. One novel p.Y526F mutation in FUS was detected in one familial ALS proband. Another novel FUS p.Q140R variant and two known FUS mutations (p.R495Efs*33 and p.R521C) were identified in four sporadic ALS cases. The frequency of FUS mutation in our cohort is 6.7% in familial ALS and 1.5% in sporadic ALS. The familial ALS proband carrying the FUS p.Y526F mutation presented with juvenile-onset lower limbs weakness and demonstrated an aggressive course, with respiratory muscles involvement 6 months after onset. The other patients in the family all had limbs weakness and died 1-2 years after disease onset. Our results strengthen that FUS mutations are the most frequent genetic causes of young-onset aggressive ALS. Genetic testing of the FUS gene should be performed in early-onset ALS patients especially those with a rapid progression.


Asunto(s)
Esclerosis Amiotrófica Lateral , Esclerosis Amiotrófica Lateral/genética , Exones , Pruebas Genéticas , Humanos , Mutación/genética , Proteína FUS de Unión a ARN/genética
11.
Neurobiol Aging ; 107: 168-173, 2021 11.
Artículo en Inglés | MEDLINE | ID: mdl-34175147

RESUMEN

Amyotrophic lateral sclerosis (ALS) is a progressive neurodegenerative disorder that predominately involves the motor neurons in the brain and spinal cord. The TARDBP gene, encoding TAR DNA-binding protein 43 (TDP-43) protein, has been identified as a major causative gene in ALS. In this study, we screened 275 SALS patients and 20 unrelated FALS probands for TARDBP mutations. We identified three TARDBP mutations in three SALS patients and two TARDBP mutations in two FALS probands, including a previously unreported mutation, p.K176I, in FALS patients consistent with frontotemporal dementia (FTD) and parkinsonism. The p.K176I mutation is the first mutation outside exon 6 of the TARDBP gene manifesting parkinsonism and the first TARDBP mutation manifesting parkinsonism identified in the Chinese population. Our results support that TARDBP mutations are one of the most common changes in both FALS and SALS in China. Patients with TARDBP mutations may have a broad phenotype spectrum of ALS, FTD, and parkinsonism. The TARDBP gene should be included in genetic screening for ALS with FTD, and/or parkinsonism.


Asunto(s)
Esclerosis Amiotrófica Lateral/genética , Proteínas de Unión al ADN/genética , Demencia Frontotemporal/genética , Mutación Missense/genética , Trastornos Parkinsonianos/genética , Adulto , Anciano , Esclerosis Amiotrófica Lateral/complicaciones , Esclerosis Amiotrófica Lateral/diagnóstico , Pueblo Asiatico/genética , China , Femenino , Demencia Frontotemporal/complicaciones , Demencia Frontotemporal/diagnóstico , Estudios de Asociación Genética , Pruebas Genéticas , Humanos , Masculino , Persona de Mediana Edad , Trastornos Parkinsonianos/complicaciones , Trastornos Parkinsonianos/diagnóstico
12.
Hortic Res ; 7: 20, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32133148

RESUMEN

Cold stress profoundly affects plant growth and development and is a key factor affecting the geographic distribution and evolution of plants. Plants have evolved adaptive mechanisms to cope with cold stress. Here, through the genomic analysis of Arabidopsis, three Brassica species and 17 other representative species, we found that both cold-related genes (CRGs) and their collinearity were preferentially retained after polyploidization followed by genome instability, while genome-wide gene sets exhibited a variety of other expansion mechanisms. The cold-related regulatory network was increased in Brassicaceae genomes, which were recursively affected by polyploidization. By combining our findings regarding the selective retention of CRGs from this ecological genomics study with the available knowledge of cold-induced chromosome doubling, we hypothesize that cold stress may have contributed to the success of polyploid plants through both increasing polyploidization and selectively maintaining CRGs during evolution. This hypothesis requires further biological and ecological exploration to obtain solid supporting evidence, which will potentially contribute to understanding the generation of polyploids and to the field of ecological genomics.

13.
Ann Clin Transl Neurol ; 6(2): 401-405, 2019 02.
Artículo en Inglés | MEDLINE | ID: mdl-30847374

RESUMEN

Vaccinia-related kinase 1 (VRK1) mutations can cause motor phenotypes including axonal sensorimotor neuropathy, distal hereditary motor neuropathy (dHMN), spinal muscular atrophy, and amyotrophic lateral sclerosis. Here, we identify a novel homozygous VRK1 p.W375X mutation causing recessive dHMN. The proband presented with juvenile onset of weakness in the distal lower extremities, slowly progressing to the distal upper limbs, with bilateral pes cavus and no upper motor or sensory neuron involvement. Nerve conduction studies showed a pure motor axonal neuropathy. Our findings extend the ethnic distribution of VRK1 mutations, indicating that these mutations should be included in genetic diagnostic testing for dHMN.


Asunto(s)
Neuropatía Hereditaria Motora y Sensorial/genética , Neuropatía Hereditaria Motora y Sensorial/patología , Péptidos y Proteínas de Señalización Intracelular/genética , Atrofia Muscular Espinal/genética , Mutación/genética , Proteínas Serina-Treonina Quinasas/genética , Adulto , Neuropatía Hereditaria Motora y Sensorial/diagnóstico , Humanos , Masculino , Atrofia Muscular Espinal/diagnóstico , Linaje , Fenotipo
14.
Ann Clin Transl Neurol ; 6(12): 2377-2383, 2019 12.
Artículo en Inglés | MEDLINE | ID: mdl-31838784

RESUMEN

OBJECTIVE: Mutations in optineurin (OPTN) have been identified in familial and sporadic amyotrophic lateral sclerosis (ALS). We screened a cohort of Chinese patients for mutations in optineurin. We also performed an extensive literatures review of all mutations in optineurin identified previously to detect genotype-phenotype associations. METHODS: All 16 exons of the OPTN gene in a cohort of 15 familial ALS indexes and 275 sporadic ALS patients of Chinese origin were sequenced by targeted next generation sequencing. RESULTS: Two known heterozygous missense mutations in the OPTN, c.1481T> G (p.L494W), and c.1546G> C (p.E516Q), as well as one novel heterozygous missense mutation c.1690G> C (p.D564H) were each detected in one sporadic ALS patient. The patient carrying the p.E516Q mutation developed clinical features of ALS-frontotemporal dementia (FTD) and the patient carrying the p.D564H mutation showed a phenotype of ALS. They both had an aggressive course, with a survival of 18 and 14 months respectively. Literature review showed that the clinical phenotypes in OPTN mutated ALS were not homogeneous, although some individuals showed a relatively slow progression and a long duration, some mutations carriers developed an aggressive progression and a short survival. INTERPRETATION: OPTN mutations contribute to ALS in Chinese population and account for 0.8% of sporadic ALS patients and 1.5% of familial ALS in the pooled Chinese ALS cohorts. Mutations in optineurin can cause aggressive ALS+/-FTD.


Asunto(s)
Esclerosis Amiotrófica Lateral/genética , Proteínas de Ciclo Celular/genética , Demencia Frontotemporal/genética , Proteínas de Transporte de Membrana/genética , Adulto , Esclerosis Amiotrófica Lateral/fisiopatología , Estudios de Cohortes , Femenino , Demencia Frontotemporal/fisiopatología , Humanos , Masculino , Persona de Mediana Edad
15.
Spectrochim Acta A Mol Biomol Spectrosc ; 118: 972-80, 2014 Jan 24.
Artículo en Inglés | MEDLINE | ID: mdl-24161860

RESUMEN

A novel ligand with double sulfinyl groups, bis(benzylsulfinyl)methane L, was synthesized by a new method. Its novel ternary complex, EuL2.5⋅L'·(ClO4)2⋅5H2O, has been synthesized [using L as the first ligand, and benzoic acid L' as the second ligand], and characterized by elemental analysis, molar conductivity, coordination titration analysis, FTIR, TG-DSC, (1)H NMR and UV-vis. In order to study the effect of the second ligand on the fluorescence properties of rare-earth sulfoxide complex, a novel binary complex EuL2.5·(ClO4)3·3H2O has been synthesized. Photoluminescent measurement showed that the first ligand L could efficiently transfer the energy to Eu(3+) ions in the complex. Furthermore, the detailed luminescence analyses on the rare earth complexes indicated that the ternary Eu (III) complex manifested stronger fluorescence intensities, longer lifetimes, and higher fluorescence quantum efficiencies than the binary Eu (III) materials. After introducing the second ligand L', the fluorescence emission intensities and fluorescence lifetimes of the ternary complex enhanced more obviously than the binary complex. This illustrated that the presence of both the first ligand L and the second ligand L' could sensitize fluorescence intensities of Eu (III) ions. The fluorescence spectra, fluorescence lifetime and phosphorescence spectra were also discussed. To explore the potential biological value of Eu (III) complexes, the binding interaction among Eu (III) complexes and bovine serum albumin (BSA) was studied by fluorescence spectrum. The result indicated that the reaction between Eu (III) complexes and BSA was a static quenching procedure. The binding site number, n, of 0.60 and 0.78, and binding constant, Ka, of 0.499 and 4.46 were calculated according to the double logarithm regression equation, respectively for EuL2.5⋅L'⋅(ClO4)2⋅5H2O and EuL2.5⋅(ClO4)3⋅3H2O systems.


Asunto(s)
Ácido Benzoico/química , Complejos de Coordinación/química , Europio/química , Percloratos/química , Albúmina Sérica Bovina/metabolismo , Animales , Ácido Benzoico/metabolismo , Sitios de Unión , Bovinos , Complejos de Coordinación/metabolismo , Europio/metabolismo , Fluorescencia , Metano/química , Metano/metabolismo , Percloratos/metabolismo , Unión Proteica , Albúmina Sérica Bovina/química , Espectrometría de Fluorescencia
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