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1.
Mult Scler ; 30(2): 156-165, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38145319

RESUMO

BACKGROUND: There are no specific, evidence-based recommendations for the management of individuals with radiologically isolated syndrome. Imaging and blood biomarkers may have prognostic utility. OBJECTIVE: To determine whether plasma neurofilament light protein (NfL) or glial fibrillary acidic protein (GFAP) levels in people with radiologically isolated syndrome correlate with imaging measures that have been shown to be associated with negative clinical outcomes in people with multiple sclerosis. METHODS: Cross-sectional analysis of people with radiologically isolated syndrome. Participants underwent magnetic resonance imaging (MRI) of the brain and cervical spinal cord, and plasma was collected. Plasma NfL and GFAP levels were measured with a single-molecule array, and correlations with MRI measures were assessed, including the number of: T1-black holes, white-matter lesions demonstrating the central vein sign, paramagnetic rim lesions, cervical spinal cord lesions and infratentorial lesions. RESULTS: Plasma GFAP levels, but not NfL levels, showed correlations with the number of T1-black holes, white matter lesions demonstrating the central vein sign and paramagnetic rim lesions (all p < 0.05). CONCLUSION: We found correlations between plasma GFAP levels and imaging measures associated with poor clinical outcomes and chronic inflammation in individuals with radiologically isolated syndrome. Plasma GFAP may have prognostic utility in clinical trials and clinical practice.


Assuntos
Doenças Desmielinizantes , Esclerose Múltipla , Humanos , Biomarcadores , Estudos Transversais , Doenças Desmielinizantes/diagnóstico por imagem , Proteína Glial Fibrilar Ácida , Filamentos Intermediários/patologia , Esclerose Múltipla/diagnóstico , Proteínas de Neurofilamentos
2.
Mult Scler ; 29(4-5): 595-605, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36840605

RESUMO

BACKGROUND: Reports suggest a potential association between coronavirus disease 2019 (COVID-19) vaccines and acute central nervous system (CNS) inflammation. OBJECTIVE: The main objective of this study is to describe features of acute CNS inflammation following COVID-19 vaccination. METHODS: A retrospective observational cohort study was performed at the BARLO MS Centre in Toronto, Canada. Clinicians reported acute CNS inflammatory events within 60 days after a COVID-19 vaccine from March 2021 to August 2022. Clinical characteristics were evaluated. RESULTS: Thirty-eight patients (median age 39 (range: 20-82) years; 60.5% female) presented within 0-55 (median 15) days of a receiving a COVID-19 vaccine and were diagnosed with relapsing remitting multiple sclerosis (MS) (n = 16), post-vaccine transverse myelitis (n = 7), clinically isolated syndrome (n = 5), MS relapse (n = 4), tumefactive demyelination (n = 2), myelin oligodendrocyte glycoprotein antibody disease (n = 1), neuromyelitis optica spectrum disorder (n = 1), chronic lymphocytic inflammation with pontine perivascular enhancement responsive to steroids (n = 1) and primary autoimmune cerebellar ataxia (n = 1). Twenty-two received acute treatment and 21 started disease-modifying therapy. Sixteen received subsequent COVID-19 vaccination, of which 87.5% had no new or worsening neurological symptoms. CONCLUSION: To our knowledge, this is the largest study describing acute CNS inflammation after COVID-19 vaccination. We could not determine whether the number of inflammatory events was higher than expected.


Assuntos
COVID-19 , Neuromielite Óptica , Feminino , Humanos , Masculino , Vacinas contra COVID-19/efeitos adversos , Estudos Retrospectivos , COVID-19/prevenção & controle , Recidiva Local de Neoplasia , Sistema Nervoso Central , Estudos de Coortes , Inflamação/etiologia , Vacinação/efeitos adversos , Glicoproteína Mielina-Oligodendrócito
3.
Int J Mol Sci ; 24(9)2023 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-37175865

RESUMO

The widespread role of titanium (IV) oxide (TiO2) in many industries makes this substance of broad scientific interest. TiO2 can act as both a photoprotector and photocatalyst, and the potential for its role in both applications increases when present in nanometer-sized crystals. Its sunlight-scattering properties are used extensively in sunscreens. Furthermore, attempts have been made to incorporate TiO2 into dermal formulations of photolabile drugs. However, the propensity to generate reactive oxygen species (ROS) rendering this material potentially cytotoxic limits its role. Therefore, modifications of TiO2 nanoparticles (e.g., its polymorphic form, size, shape, and surface modifications) are used in an effort to reduce its photocatalytic effects. This review provides an overview of the potential risks arising from and opportunities presented by the use of TiO2 in skin care formulations.


Assuntos
Dermatite Fototóxica , Nanopartículas , Humanos , Titânio/química , Óxidos , Nanopartículas/química
4.
Molecules ; 28(18)2023 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-37764227

RESUMO

A review of the current literature shows there is no clear consensus regarding the reaction mechanisms of air-borne aromatic compounds such as toluene by photocatalytic oxidation. Potential oxidation reactions over TiO2 or TiO2-based catalysts under ultraviolet and visible (UV/VIS) illumination are most commonly considered for removal of these pollutants. Along the pathways from a model pollutant, toluene, to final mineralization products (CO2 and H2O), the formation of several intermediates via specific reactions include parallel oxidation reactions and formation of less-reactive intermediates on the TiO2 surface. The latter may occupy active adsorption sites and causes drastic catalyst deactivation in some cases. Major hazardous gas-phase intermediates are benzene and formaldehyde, classified by the International Agency for Research on Cancer (IARC) as Group 1 carcinogenic compounds. Adsorbed intermediates leading to catalyst deactivation are benzaldehyde, benzoic acid, and cresols. The three most typical pathways of toluene photocatalytic oxidation are reviewed: methyl group oxidation, aromatic ring oxidation, and aromatic ring opening.

5.
Curr Neurol Neurosci Rep ; 22(11): 721-734, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36301434

RESUMO

PURPOSE OF REVIEW: Multiple sclerosis (MS) is an inflammatory disease of the central nervous system (CNS) with a chronic and often progressive disease course. The current disease-modifying treatments (DMTs) limit disease progression primarily by dampening immune cell activity in the peripheral blood or hindering their migration from the periphery into the CNS. New therapies are needed to target CNS immunopathology, which is a key driver of disability progression in MS. This article reviews Bruton's Tyrosine Kinase Inhibitors (BTKIs), a new class of experimental therapy that is being intensely evaluated in MS. We focus on the potential peripheral and central mechanisms of action of BTKIs and their use in recent clinical trials in MS. RECENT FINDINGS: There is evidence that some BTKIs cross the blood-brain barrier and may be superior to currently available DMTs at dampening the chronic neuroinflammatory processes compartmentalized within the CNS that contribute to progressive worsening in people withMS (pwMS). Recently, evobrutinib and tolebrutinib have shown efficacy in phase II clinical trials, and there are numerous ongoing phase III clinical trials of various BTKIs in relapsing and progressive forms of MS. Results from these clinical trials will be essential to understand the efficacy and safety of BTKIs across the spectrum of MS and keydifferences between specific BTKIs when treating pwMS. Inhibition of BTK has emerged as an attractive strategy to target cells of the adaptive and innate immune system outside and within the CNS. BTKIs carry great therapeutic potential across the MS spectrum, where key pathobiology aspects seem confined to the CNS compartment.


Assuntos
Tirosina Quinase da Agamaglobulinemia , Esclerose Múltipla , Inibidores de Proteínas Quinases , Humanos , Tirosina Quinase da Agamaglobulinemia/antagonistas & inibidores , Sistema Nervoso Central , Esclerose Múltipla/tratamento farmacológico , Inibidores de Proteínas Quinases/farmacocinética , Inibidores de Proteínas Quinases/uso terapêutico , Ensaios Clínicos Fase II como Assunto , Ensaios Clínicos Fase III como Assunto , Resultado do Tratamento
6.
Inorg Chem ; 59(9): 6220-6231, 2020 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-32319767

RESUMO

Highly fluorescent and color tunable AgInS2 (AIS) and (AgInS2)x(ZnS)1-x (AIZS) quantum dots (QDs) were prepared via a facile aqueous-phase synthesis using AgNO3, In(NO3)3, Zn(OAc)2, and Na2S as precursors and 3-mercaptopropionic acid (3-MPA) as ligand. Produced AIZS QDs exhibit a small diameter (ca. 2.1 nm) and a cubic structure. Ag-3-MPA and In-3-MPA complexes formed during the preparation of AIS cores were found to play a key role on the fate of the reaction, and an atypical blue-shift of the photoluminescence emission was observed with the increase of the Ag/In ratio. The photoluminescence quantum yield (PL QY) of AIS QDs is modest but increased markedly after the alloying and shelling with ZnS (up to 65%). Size and composition-selective precipitations allowed to separate up to 13 fractions of AIZS QDs with exceptionally high PL QYs (up to 78%), which is the highest value reported for AIZS QDs prepared in the aqueous phase. These high PL QYs combined with their good colloidal stability and photostability make AIZS QDs of high potential as cadmium-free fluorescent probes for various applications like bioimaging or sensing.

7.
Nanotechnology ; 31(46): 465704, 2020 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-32853176

RESUMO

In this work, novel heterostructured photocatalysts associating graphitic carbon nitride (g-CN) and SmFeO3 were prepared via a mixing-ultrasonication process. Structural, optical and morphological characterizations demonstrate that the interfacial junction between g-CN and SmFeO3 is well established for all g-CN/SmFeO3 composites prepared with g-CN:SmFeO3 weight ratio of 20:80, 50:50 and 80:20. The g-CN/SmFeO3 (80:20) composite exhibits the highest photocatalytic activity for the degradation of pollutants like the Orange II dye and the tetracycline hydrochloride antibiotic under visible light irradiation. This high photocatalytic activity originates from the enhanced light absorption over the whole visible region compared to pure g-CN and from the improved separation and transfer of photogenerated electron/hole pairs as demonstrated by photoluminescence and photocurrent measurements. A Z-scheme charge carrier transfer mechanism was demonstrated for the photocatalytic reactions. The g-CN/SmFeO3 (80:20) catalyst was also demonstrated to be stable and can be reused up to six times without significant alteration of the activity.

8.
Int J Mol Sci ; 21(14)2020 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-32659965

RESUMO

There are many studies concerning titanium dioxide (TiO2) nanoparticles (NP) toxicity. Nevertheless, there are few publications comparing in vitro and in vivo exposure, and even less comparing air-liquid interface exposure (ALI) with other in vitro and in vivo exposures. The identification and validation of common markers under different exposure conditions are relevant for the development of smart and quick nanotoxicity tests. In this work, cell viability was assessed in vitro by WST-1 and LDH assays after the exposure of NR8383 cells to TiO2 NP sample. To evaluate in vitro gene expression profile, NR8383 cells were exposed to TiO2 NP during 4 h at 3 cm2 of TiO2 NP/cm2 of cells or 19 µg/mL, in two settings-submerged cultures and ALI. For the in vivo study, Fischer 344 rats were exposed by inhalation to a nanostructured aerosol at a concentration of 10 mg/m3, 6 h/day, 5 days/week for 4 weeks. This was followed immediately by gene expression analysis. The results showed a low cytotoxic potential of TiO2 NP on NR8383 cells. Despite the absence of toxicity at the doses studied, the different exposures to TiO2 NP induce 18 common differentially expressed genes (DEG) which are involved in mitosis regulation, cell proliferation and apoptosis and inflammation transport of membrane proteins. Among these genes, we noticed the upregulation of Ccl4, Osm, Ccl7 and Bcl3 genes which could be suggested as early response biomarkers after exposure to TiO2 NP. On the other hand, the comparison of the three models helped us to validate the alternative ones, namely submerged and ALI approaches.


Assuntos
Nanopartículas/toxicidade , Titânio/toxicidade , Administração por Inalação , Aerossóis/toxicidade , Animais , Apoptose/efeitos dos fármacos , Biomarcadores/metabolismo , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Inflamação , Masculino , Proteínas de Membrana/metabolismo , Mitose/efeitos dos fármacos , Nanoestruturas/toxicidade , Ratos , Ratos Endogâmicos F344 , Transcriptoma/efeitos dos fármacos
9.
Water Sci Technol ; 82(3): 454-467, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32960791

RESUMO

Many attempts have been made to improve the photocatalytic performance of immobilized photocatalysts for large-scale applications by modification of the photocatalyst properties. In this work, immobilized bilayer photocatalyst composed of titanium dioxide (TiO2) and chitosan-montmorillonite (CS-MT) were prepared in a layer-by-layer arrangement supported on glass substrate. This arrangement allows a simultaneous occurrence of adsorption and photocatalysis processes of pollutants, whereby each layer could be independently modified and controlled to acquire the desired degree of occurring processes. It was found that the addition of MT clay within the CS composite sub-layer improved the mechanical strength of CS, reduced its swelling and shifted its absorption threshold to higher wavelengths. In addition, the band gap energy of the photocatalyst was also reduced to 2.93 eV. The immobilized TiO2/CS-MT exhibited methyl orange (MO) decolourization rate of 0.071 min-1 under light irradiation, which is better than the single TiO2 due to the synergistic processes of adsorption by CS-MT and photocatalysis by TiO2 layer. The MO dye took 6 h to achieve complete mineralization and produced sulfate and nitrate ions as the by-products. Furthermore, the immobilized TiO2/CS-MT could be reused for at least ten cycles of application without significant loss of its activity.


Assuntos
Bentonita , Quitosana , Compostos Azo , Catálise , Fotólise , Titânio
10.
Acta Neuropathol ; 137(3): 501-519, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30701273

RESUMO

The identification of genes implicated in myopathies is essential for diagnosis and for revealing novel therapeutic targets. Here we characterize a novel subclass of congenital myopathy at the morphological, molecular, and functional level. Through exome sequencing, we identified de novo ACTN2 mutations, a missense and a deletion, in two unrelated patients presenting with progressive early-onset muscle weakness and respiratory involvement. Morphological and ultrastructural analyses of muscle biopsies revealed a distinctive pattern with the presence of muscle fibers containing small structured cores and jagged Z-lines. Deeper analysis of the missense mutation revealed mutant alpha-actinin-2 properly localized to the Z-line in differentiating myotubes and its level was not altered in muscle biopsy. Modelling of the disease in zebrafish and mice by exogenous expression of mutated alpha-actinin-2 recapitulated the abnormal muscle function and structure seen in the patients. Motor deficits were noted in zebrafish, and muscle force was impaired in isolated muscles from AAV-transduced mice. In both models, sarcomeric disorganization was evident, while expression of wild-type alpha-actinin-2 did not result in muscle anomalies. The murine muscles injected with mutant ACTN2 displayed cores and Z-line defects. Dominant ACTN2 mutations were previously associated with cardiomyopathies, and our data demonstrate that specific mutations in the well-known Z-line regulator alpha-actinin-2 can cause a skeletal muscle disorder.


Assuntos
Actinina/genética , Músculo Esquelético/patologia , Miotonia Congênita/genética , Miotonia Congênita/patologia , Animais , Feminino , Humanos , Masculino , Camundongos , Mutação , Peixe-Zebra
11.
Nanotechnology ; 30(4): 045707, 2019 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-30479317

RESUMO

Binary spinel-type metal oxides (AB2O4) related materials, including ferrites (AFe2O4), are attractive photocatalysts thanks to their excellent visible light response for the photodegradation of organic pollutants. Currently, these materials are synthesized via conventional chemical routes suffering from long preparation duration and multistep. Moreover, the photocatalysts are obtained as nano-powders from conventional chemical routes would introduce another drawback for their recycling and reuse. From an industrial perspective, it is desirable to develop an efficient and facile synthesis process to produce photocatalysts in a non-dispersible form. Herein, we demonstrate that the solution precursor plasma spray (SPPS) process is a single-step method for depositing photocatalytically active zinc ferrite-based films within several minutes. The influence of the precursor ratio on the microstructures and phase compositions of the ZnFe2O4 films was investigated by XRD and Raman analyses. In addition, two optimized ZnFe2O4 films were prepared by increasing the ZnO loading and tailoring injection pattern of the precursor solution. The surface morphologies and optical bandgap were also determined by SEM and UV-visible spectroscopy. The photocatalytic activities of the ZnFe2O4 films were evaluated through the degradation of the Orange II dye and of tetracycline hydrochloride under UV or visible light irradiation. The results show that compositional ratios and composition distribution of the ZnFe2O4 films prepared via SPPS played a key role on the photocatalytic activity. The SPPS route was demonstrated to be a promising method for the synthesis and the deposition of metal oxide (i.e. perovskite type and spinel type) films within a single-step for functional applications.

12.
Brain ; 141(10): 2895-2907, 2018 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-30252044

RESUMO

The G4C2-repeat expansion in C9orf72 is the most common known cause of amyotrophic lateral sclerosis and frontotemporal dementia. The high phenotypic heterogeneity of C9orf72 patients includes a wide range in age of onset, modifiers of which are largely unknown. Age of onset could be influenced by environmental and genetic factors both of which may trigger DNA methylation changes at CpG sites. We tested the hypothesis that age of onset in C9orf72 patients is associated with some common single nucleotide polymorphisms causing a gain or loss of CpG sites and thus resulting in DNA methylation alterations. Combined analyses of epigenetic and genetic data have the advantage of detecting functional variants with reduced likelihood of false negative results due to excessive correction for multiple testing in genome-wide association studies. First, we estimated the association between age of onset in C9orf72 patients (n = 46) and the DNA methylation levels at all 7603 CpG sites available on the 450 k BeadChip that are mapped to common single nucleotide polymorphisms. This was followed by a genetic association study of the discovery (n = 144) and replication (n = 187) C9orf72 cohorts. We found that age of onset was reproducibly associated with polymorphisms within a 124.7 kb linkage disequilibrium block tagged by top-significant variation, rs9357140, and containing two overlapping genes (LOC101929163 and C6orf10). A meta-analysis of all 331 C9orf72 carriers revealed that every A-allele of rs9357140 reduced hazard by 30% (P = 0.0002); and the median age of onset in AA-carriers was 6 years later than GG-carriers. In addition, we investigated a cohort of C9orf72 negative patients (n = 2634) affected by frontotemporal dementia and/or amyotrophic lateral sclerosis; and also found that the AA-genotype of rs9357140 was associated with a later age of onset (adjusted P = 0.007 for recessive model). Phenotype analyses detected significant association only in the largest subgroup of patients with frontotemporal dementia (n = 2142, adjusted P = 0.01 for recessive model). Gene expression studies of frontal cortex tissues from 25 autopsy cases affected by amyotrophic lateral sclerosis revealed that the G-allele of rs9357140 is associated with increased brain expression of LOC101929163 (a non-coding RNA) and HLA-DRB1 (involved in initiating immune responses), while the A-allele is associated with their reduced expression. Our findings suggest that carriers of the rs9357140 GG-genotype (linked to an earlier age of onset) might be more prone to be in a pro-inflammatory state (e.g. by microglia) than AA-carriers. Further, investigating the functional links within the C6orf10/LOC101929163/HLA-DRB1 pathway will be critical to better define age-dependent pathogenesis of frontotemporal dementia and amyotrophic lateral sclerosis.


Assuntos
Esclerose Lateral Amiotrófica/genética , Proteína C9orf72/genética , Demência Frontotemporal/genética , Regulação da Expressão Gênica/genética , Idade de Início , Idoso , Ilhas de CpG , Metilação de DNA , Feminino , Genótipo , Heterozigoto , Humanos , Masculino , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único
13.
Molecules ; 24(13)2019 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-31284390

RESUMO

Nitric oxide (NO) is naturally synthesized in the human body and presents many beneficial biological effects; in particular on the cardiovascular system. Recently; many researchers tried to develop external sources to increase the NO level in the body; for example by using amidoximes and oximes which can be oxidized in vivo and release NO. In this review; the classical methods and most recent advances for the synthesis of both amidoximes and oximes are presented first. The isomers of amidoximes and oximes and their stabilities will also be described; (Z)-amidoximes and (Z)-oximes being usually the most energetically favorable isomers. This manuscript details also the biomimetic and biological pathways involved in the oxidation of amidoximes and oximes. The key role played by cytochrome P450 or other dihydronicotinamide-adenine dinucleotide phosphate (NADPH)-dependent reductase pathways is demonstrated. Finally, amidoximes and oximes exhibit important effects on the relaxation of both aortic and tracheal rings alongside with other effects as the decrease of the arterial pressure and of the thrombi formation.


Assuntos
Doadores de Óxido Nítrico/química , Doadores de Óxido Nítrico/síntese química , Oximas/química , Oximas/síntese química , Isomerismo , Óxido Nítrico/metabolismo , Oxirredução
14.
Am J Hum Genet ; 96(6): 962-70, 2015 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-26004200

RESUMO

An expanded G4C2 repeat in C9orf72 represents the most common known genetic cause of amyotrophic lateral sclerosis (ALS) and frontotemporal lobar degeneration (FTLD). However, the lower limit for pathological expansions is unknown (the suggested cutoff is 30 repeats). It has been proposed that the expansion might have occurred only once in human history and subsequently spread throughout the population. However, our present findings support a hypothesis of multiple origins for the expansion. We report a British-Canadian family in whom a ∼70-repeat allele from the father (unaffected by ALS or FTLD at age 89 years) expanded during parent-offspring transmission and started the first generation affected by ALS (four children carry an ∼1,750-repeat allele). Epigenetic and RNA-expression analyses further discriminated the offspring's large expansions (which were methylated and associated with reduced C9orf72 expression) from the ∼70-repeat allele (which was unmethylated and associated with upregulation of C9orf72). Moreover, RNA foci were only detected in fibroblasts from offspring with large expansions, but not in the father, who has the ∼70-repeat allele. All family members with expansions were found to have an ancient known risk haplotype, although it was inherited on a unique 5-Mb genetic backbone. We conclude that small expansions (e.g., 70 repeats) might be considered "pre-mutations" to reflect their propensity to expand in the next generation. Follow-up studies might help explain the high frequency of ALS- or FTLD-affected individuals with an expansion but without a familial history (e.g., 21% among Finnish ALS subjects).


Assuntos
Esclerose Lateral Amiotrófica/genética , Esclerose Lateral Amiotrófica/patologia , Expansão das Repetições de DNA/genética , Degeneração Lobar Frontotemporal/genética , Degeneração Lobar Frontotemporal/patologia , Proteínas/genética , Southern Blotting , Proteína C9orf72 , Canadá , Metilação de DNA/genética , Haplótipos/genética , Humanos , Linhagem , Reação em Cadeia da Polimerase
15.
Bioconjug Chem ; 29(7): 2248-2256, 2018 07 18.
Artigo em Inglês | MEDLINE | ID: mdl-29906097

RESUMO

Biocompatible thermoresponsive copolymers based on 2-(2-methoxyethoxy) ethyl methacrylate (MEO2MA) and oligo (ethylene glycol) methacrylate (OEGMA) were grown from the surface of ZnO quantum dots (QDs) by surface initiated atom transfer radical polymerization with activators regenerated by electron transfer (SI-ARGET ATRP) in order to design smart and fluorescent core/shell nanosystems to be used toward cancer cells. Tunable lower critical solution temperature (LCST) values were obtained and studied in water and in culture medium. The complete efficiency of the process was demonstrated by the combination of spectroscopic and microscopic studies. The colloidal behavior of the ZnO/copolymer core/shell QDs in water and in physiological media with temperature was assessed. Finally, the cytotoxicity toward human colon cancer HT29 cells of the core/shell QDs was tested. The results showed that the polymer-capped QDs exhibited almost no toxicity at concentrations up to 12.5 µg.mL-1, while when loaded with doxorubicin hydrochloride (DOX), a higher cytotoxicity and a decreased HT29 cancer cell viability in a short time were observed.


Assuntos
Doxorrubicina/administração & dosagem , Sistemas de Liberação de Medicamentos/métodos , Neoplasias/tratamento farmacológico , Pontos Quânticos/uso terapêutico , Sobrevivência Celular/efeitos dos fármacos , Coloides , Doxorrubicina/farmacologia , Células HT29 , Humanos , Metacrilatos/química , Polimerização , Pontos Quânticos/química , Pontos Quânticos/toxicidade , Óxido de Zinco
16.
Ann Neurol ; 81(3): 467-473, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28220527

RESUMO

Congenital myopathies are phenotypically and genetically heterogeneous. We describe homozygous truncating mutations in MYPN in 2 unrelated families with a slowly progressive congenital cap myopathy. MYPN encodes the Z-line protein myopalladin implicated in sarcomere integrity. Functional experiments demonstrate that the mutations lead to mRNA defects and to a strong reduction in full-length protein expression. Myopalladin signals accumulate in the caps together with alpha-actinin. Dominant MYPN mutations were previously reported in cardiomyopathies. Our data uncover that mutations in MYPN cause either a cardiac or a congenital skeletal muscle disorder through different modes of inheritance. Ann Neurol 2017;81:467-473.


Assuntos
Proteínas Musculares/genética , Miopatias Congênitas Estruturais/genética , Adulto , Consanguinidade , Exoma , Feminino , Humanos , Masculino , Mutação , Miopatias Congênitas Estruturais/patologia , Miopatias Congênitas Estruturais/fisiopatologia , Linhagem
17.
J Neurol Neurosurg Psychiatry ; 89(8): 851-858, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29434051

RESUMO

OBJECTIVE: To determine whether exosomal microRNAs (miRNAs) in cerebrospinal fluid (CSF) of patients with frontotemporal dementia (FTD) can serve as diagnostic biomarkers, we assessed miRNA expression in the Genetic Frontotemporal Dementia Initiative (GENFI) cohort and in sporadic FTD. METHODS: GENFI participants were either carriers of a pathogenic mutation in progranulin, chromosome 9 open reading frame 72 or microtubule-associated protein tau or were at risk of carrying a mutation because a first-degree relative was a known symptomatic mutation carrier. Exosomes were isolated from CSF of 23 presymptomatic and 15 symptomatic mutation carriers and 11 healthy non-mutation carriers. Expression of 752 miRNAs was measured using quantitative PCR (qPCR) arrays and validated by qPCR using individual primers. MiRNAs found differentially expressed in symptomatic compared with presymptomatic mutation carriers were further evaluated in a cohort of 17 patients with sporadic FTD, 13 patients with sporadic Alzheimer's disease (AD) and 10 healthy controls (HCs) of similar age. RESULTS: In the GENFI cohort, miR-204-5p and miR-632 were significantly decreased in symptomatic compared with presymptomatic mutation carriers. Decrease of miR-204-5p and miR-632 revealed receiver operator characteristics with an area of 0.89 (90% CI 0.79 to 0.98) and 0.81 (90% CI 0.68 to 0.93), respectively, and when combined an area of 0.93 (90% CI 0.87 to 0.99). In sporadic FTD, only miR-632 was significantly decreased compared with AD and HCs. Decrease of miR-632 revealed an area of 0.90 (90% CI 0.81 to 0.98). CONCLUSIONS: Exosomal miR-204-5p and miR-632 have potential as diagnostic biomarkers for genetic FTD and miR-632 also for sporadic FTD.


Assuntos
Regulação para Baixo , Exossomos/metabolismo , Demência Frontotemporal/genética , MicroRNAs/genética , Biomarcadores , Feminino , Demência Frontotemporal/líquido cefalorraquidiano , Humanos , Masculino , MicroRNAs/líquido cefalorraquidiano , Proteínas tau/líquido cefalorraquidiano
18.
Bioorg Med Chem Lett ; 28(20): 3329-3332, 2018 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-30243591

RESUMO

Four compounds bearing amidoxime functions were synthetized: (1) 2a,b bearing an aromatic amidoxime function, (2) 2c bearing an aliphatic amidoxime function, and (3) 2d bearing aromatic and aliphatic amidoximes functions. The ability of these compounds to release NO was evaluated in vitro using the oxidative metabolism of cytochrome P450 from rat liver microsomes. Results obtained demonstrate that all amidoximes were able to release NO with a highest amount of NO produced by the 2a aromatic amidoxime. Moreover, all amidoximes exhibit cytocompatibility with human aorta smooth muscle cells. Using intracellular S-nitrosothiol formation as a marker of NO bioavailability, compounds 2a-c were demonstrated to deliver a higher amount of NO in the intracellular environment than the reference. Considering that the concentration of the bis-amidoxime 2d was two times lower that than of 2a and 2b, we can assume that 2d is the most potent molecule among the tested compounds for NO release.


Assuntos
Doadores de Óxido Nítrico/farmacologia , Oximas/farmacologia , Animais , Liberação Controlada de Fármacos , Humanos , Microssomos Hepáticos/metabolismo , Estrutura Molecular , Miócitos de Músculo Liso/efeitos dos fármacos , Doadores de Óxido Nítrico/síntese química , Doadores de Óxido Nítrico/toxicidade , Oximas/síntese química , Oximas/toxicidade , Ratos
19.
Clin Invest Med ; 41(1): E31-E33, 2018 03 27.
Artigo em Inglês | MEDLINE | ID: mdl-29603689

RESUMO

In their landmark paper, Mendell et al. show that infants with spinal muscular atrophy (SMA) reached important motor milestones and survived longer when treated with AVXS-101 (AveXis), a viral vector containing DNA encoding the survival of motor neuron protein (SMN). Patients not only crawled, stood and walked independently, but learned to speak. These results are very encouraging for patients with SMA and offer hope for pediatric and adult patients with other types of motor neuron diseases.


Assuntos
Atrofia Muscular Espinal , Proteína 1 de Sobrevivência do Neurônio Motor/genética , Criança , Terapia Genética , Humanos , Lactente
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