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1.
JNCI Cancer Spectr ; 2024 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-38730548

RESUMO

BACKGROUND: Traditional constraints specify that 700 cc of liver should be spared a hepatotoxic dose when delivering liver-directed radiotherapy to reduce the risk of inducing liver failure. We investigated the role of single photon emission computed tomography (SPECT) to identify and preferentially avoid functional liver during liver-directed radiation treatment planning in patients with preserved liver function but limited functional liver volume after receiving prior hepatotoxic chemotherapy or surgical resection. METHODS: This phase I trial with a 3 + 3 design evaluated the safety of liver-directed radiotherapy using escalating functional liver radiation dose constraints in patients with liver metastases. Dose limiting toxicities (DLTs) were assessed 6-8 weeks and 6 months after completing radiotherapy. RESULTS: All twelve patients had colorectal liver metastases and received prior hepatotoxic chemotherapy. Eight patients underwent prior liver resection. Median computed tomography (CT) anatomical non-tumor liver volume was 1,584 cc (range 764-2,699 cc). Median SPECT functional liver volume was 1,117 cc (range 570-1,928cc). Median non-target CT and SPECT liver volumes below the volumetric dose constraint were 997 cc (range 544-1,576 cc) and 684 cc (range 429-1,244 cc), respectively. The prescription dose was 67.5-75 Gy in 15 fractions or 75-100 Gy in 25 fractions. No DLTs were observed during follow-up. One-year in-field control was 57%. One-year overall survival was 73%. CONCLUSION: Liver-directed radiotherapy can be safely delivered to high doses when incorporating functional SPECT into the radiation treatment planning process which may enable sparing of lower volumes of liver than traditionally accepted in patients with preserved liver function. TRIAL REGISTRATION: NCT02626312.

2.
Anal Chim Acta ; 1301: 342448, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38553120

RESUMO

BACKGROUND: The incorporation of bimetallic magnetic ionic liquids (MILs) in microextraction methods is an emerging trend due to the improved magnetic susceptibility offered by these solvents, which relies on the presence of metallic components in both the cation and the anion. This feature favors easy magnetic separation of these solvents in analytical sample preparation strategies. However, reported liquid-phase microextraction methods based on bimetallic MILs still present an important drawback in that the MILs are highly viscous, making a dispersive solvent during the microextraction procedure necessary, while also requiring a tedious back-extraction step prior to the chromatographic analysis. RESULTS: We propose for the first time a new generation of ultra-low viscosity bimetallic MILs composed of two paramagnetic Mn(II) complexes characterized by their easy usage in dispersive liquid-liquid microextraction (DLLME). The approach does not require dispersive solvent and the MIL-DLLME setup was directly combined with high-performance liquid chromatography (HPLC) and fluorescence detection (FD), without any back-extraction step. The approach was evaluated for the determination of five monohydroxylated polycyclic aromatic hydrocarbons, as carcinogenic biomarkers, in human urine. Optimum conditions of the MIL-DLLME method included the use of a low MIL volume (75 µL), a short extraction time (5 min), and no need of any dispersive solvent neither NaCl. The method presented limits of detection down to 7.50 ng L-1, enrichment factors higher than 17, and provided inter-day relative standard deviation lower than 11%. Analysis of urine samples was successfully performed, with biomarker content found at levels between 0.24 and 7.8 ng mL-1. SIGNIFICANCE: This study represents the first liquid-phase microextraction method using the new generation of low-viscous bimetallic MILs. The proposed MIL-DLLME approach represents 2 important advances with respect to previous methods employing bimetallic MILs: 1) no dispersive solvent is required, and 2) direct injection of the MIL in the HPLC is possible after minor dilution (no back extraction steps are required). Therefore, the microextraction strategy is simple, rapid, and consumes very small amounts of energy.

3.
iScience ; 26(11): 108152, 2023 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-37920668

RESUMO

MicroRNAs (miRNAs) modulate mRNA expression, and their deregulation contributes to various diseases including amyotrophic lateral sclerosis (ALS). As fused in sarcoma (FUS) is a causal gene for ALS and regulates biogenesis of miRNAs, we systematically analyzed the miRNA repertoires in spinal cords and hippocampi from ALS-FUS mice to understand how FUS-dependent miRNA deregulation contributes to ALS. miRNA profiling identified differentially expressed miRNAs between different central nervous system (CNS) regions as well as disease states. Among the up-regulated miRNAs, miR-1197 targets the pro-survival pseudokinase Trib2. A reduced TRIB2 expression was observed in iPSC-derived motor neurons from ALS patients. Pharmacological stabilization of TRIB2 protein with a clinically approved cancer drug rescues the survival of iPSC-derived human motor neurons, including those from a sporadic ALS patient. Collectively, our data indicate that miRNA profiling can be used to probe the molecular mechanisms underlying selective vulnerability, and TRIB2 is a potential therapeutic target for ALS.

4.
Front Immunol ; 14: 1165852, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37334360

RESUMO

Introduction: Lipid transfer proteins (LTPs) are allergens found in a wide range of plant-foods. Specifically, Pru p 3, the major allergen of peach, is commonly responsible for severe allergic reactions. The need for new alternatives to conventional food allergy treatments, like restrictive diets, suggests allergen immunotherapy as a promising option. It has been demonstrated that sublingual immunotherapy (SLIT) with synthetic glycodendropeptides, such as D1ManPrup3, containing mannose and Pru p 3 peptides induced tolerance in mice and that the persistence of this effect depends on treatment dose (2nM or 5nM). Moreover, it produces changes associated with differential gene expression and methylation profile of dendritic cells, as well as phenotypical changes in regulatory T cells (Treg). However, there are no works addressing the study of epigenetic changes in terms of methylation in the cell subsets that sustain tolerant responses, Treg. Therefore, in this work, DNA methylation changes in splenic-Treg from Pru p 3 anaphylactic mice were evaluated. Methods: It was performed by whole genome bisulphite sequencing comparing SLIT-D1ManPrup3 treated mice: tolerant (2nM D1ManPrup3), desensitized (5nM D1ManPrup3), and sensitized but not treated (antigen-only), with anaphylactic mice. Results: Most of the methylation changes were found in the gene promoters from both SLIT-treated groups, desensitized (1,580) and tolerant (1,576), followed by the antigen-only (1,151) group. Although tolerant and desensitized mice showed a similar number of methylation changes, only 445 genes were shared in both. Remarkably, interesting methylation changes were observed on the promoter regions of critical transcription factors for Treg function like Stat4, Stat5a, Stat5b, Foxp3, and Gata3. In fact, Foxp3 was observed exclusively as hypomethylated in tolerant group, whereas Gata3 was only hypomethylated in the desensitized mice. Discussion: In conclusion, diverse D1ManPrup3 doses induce different responses (tolerance or desensitization) in mice, which are reflected by differential methylation changes in Tregs.


Assuntos
Anafilaxia , Hipersensibilidade Alimentar , Animais , Camundongos , Linfócitos T Reguladores , Hipersensibilidade Alimentar/terapia , Anafilaxia/metabolismo , Alérgenos/metabolismo , Metilação de DNA , Fatores de Transcrição Forkhead/metabolismo
5.
J Clin Immunol ; 43(1): 165-180, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36066697

RESUMO

Somatic mutations in the ten-eleven translocation methylcytosine dioxygenase 2 gene (TET2) have been associated to hematologic malignancies. More recently, biallelic, and monoallelic germline mutations conferring susceptibility to lymphoid and myeloid cancer have been described. We report two unrelated autoimmune lymphoproliferative syndrome-like patients who presented with T-cell lymphoma associated with novel germline biallelic or monoallelic mutations in the TET2 gene. Both patients presented a history of chronic lymphoproliferation with lymphadenopathies and splenomegaly, cytopenias, and immune dysregulation. We identified the first compound heterozygous patient for TET2 mutations (P1) and the first ALPS-like patient with a monoallelic TET2 mutation (P2). P1 had the most severe form of autosomal recessive disease due to TET2 loss of function resulting in absent TET2 expression and profound increase in DNA methylation. Additionally, the immunophenotype showed some alterations in innate and adaptive immune system as inverted myeloid/plasmacytoid dendritic cells ratio, elevated terminally differentiated effector memory CD8 + T-cells re-expressing CD45RA, regulatory T-cells, and Th2 circulating follicular T-cells. Double-negative T-cells, vitamin B12, and IL-10 were elevated according to the ALPS-like suspicion. Interestingly, the healthy P1's brother carried a TET2 mutation and presented some markers of immune dysregulation. P2 showed elevated vitamin B12, hypergammaglobulinemia, and decreased HDL levels. Therefore, novel molecular defects in TET2 confirm and expand both clinical and immunological phenotype, contributing to a better knowledge of the bridge between cancer and immunity.


Assuntos
Síndrome Linfoproliferativa Autoimune , Dioxigenases , Neoplasias Hematológicas , Masculino , Humanos , Síndrome Linfoproliferativa Autoimune/diagnóstico , Síndrome Linfoproliferativa Autoimune/genética , Mutação em Linhagem Germinativa , Neoplasias Hematológicas/diagnóstico , Neoplasias Hematológicas/genética , Mutação/genética , Fenótipo , Vitamina B 12 , Proteínas de Ligação a DNA/genética , Dioxigenases/genética
6.
J Chromatogr A ; 1685: 463577, 2022 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-36323106

RESUMO

Magnetic ionic liquids (MILs) are materials of special interest in analytical chemistry and, particularly, in analytical microextraction. These solvents possess several of the properties derived from their inherent nature of ionic liquids, combined with their magnetism, that permits their manipulation with an external magnetic field. This feature allows for performing typical steps of the microextraction procedure in a simpler manner with the aid of a strong magnet. Although there are several important reviews summarizing the most innovative advances in this field, there is a gap of information, as they do not provide useful details and tips related to the experimental set up of these procedures. This tutorial review fills this gap by providing a guide for the proper handling of MILs, their manipulation with magnets, and their proper hyphenation with the most used analytical techniques. Attention is paid to dispersive liquid-liquid microextraction, stir-bar dispersive liquid microextraction, aqueous biphasic systems, and single-drop microextraction, for being the analytical microextraction techniques mostly employed with MILs. This review also introduces a classification of the MILs employed in analytical microextraction in three classes (denoted as A, B, and C) as a function of the MIL nature (metal-containing anion, metal-containing cation, and radical-containing ion), and discuss about the prospect and future trends regarding new MIL families in microextraction together with new directions expected in these procedures.


Assuntos
Líquidos Iônicos , Microextração em Fase Líquida , Humanos , Líquidos Iônicos/química , Microextração em Fase Líquida/métodos , Magnetismo , Solventes/química , Fenômenos Magnéticos
7.
Int J Biol Macromol ; 222(Pt B): 2467-2478, 2022 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-36220405

RESUMO

SARS-CoV-2 spike (S) protein mediates virus attachment to the cells and fusion between viral and cell membranes. Membrane fusion is driven by mutual interaction between the highly conserved heptad-repeat regions 1 and 2 (HR1 and HR2) of the S2 subunit of the spike. For this reason, these S2 regions are interesting therapeutic targets for COVID-19. Although HR1 and HR2 have been described as transiently exposed during the fusion process, no significant antibody responses against these S2 regions have been reported. Here we designed chimeric proteins that imitate highly stable HR1 helical trimers and strongly bind to HR2. The proteins have broad inhibitory activity against WT B.1 and BA.1 viruses. Sera from COVID-19 convalescent donors showed significant levels of reactive antibodies (IgG and IgA) against the HR1 mimetic proteins, whereas these antibody responses were absent in sera from uninfected donors. Moreover, both inhibitory activity and antigenicity of the proteins correlate positively with their structural stability but not with the number of amino acid changes in their HR1 sequences, indicating a conformational and conserved nature of the involved epitopes. Our results reveal previously undetected spike epitopes that may guide the design of new robust COVID-19 vaccines and therapies.


Assuntos
COVID-19 , SARS-CoV-2 , Humanos , Glicoproteína da Espícula de Coronavírus/química , Proteínas do Envelope Viral/química , Epitopos , Vacinas contra COVID-19 , Glicoproteínas de Membrana/química , Proteínas Recombinantes de Fusão/genética
8.
Am J Surg Pathol ; 46(11): 1545-1553, 2022 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-35877198

RESUMO

The relationship between the ductal and lobular components of invasive ductolobular carcinomas (IDLC) has not been fully elucidated. In this study, the molecular alterations of both components were analyzed in a series of 20 IDLC that were selected, not only by morphologic criteria, but also by the loss of E-cadherin expression in the lobular component. We found that 80% of tumors shared alterations of driver genes in both components, being PIK3CA the most common alteration. In addition, 45% of IDLC carried CDH1 mutations in their lobular component that were absent in the ductal component. Fluorescent in situ hybridization analysis of the CDH1 gene excluded homozygous CDH1 loss as a frequent cause of E-cadherin loss in tumors without CDH1 mutations. In addition, no pathogenic mutations of catenin genes were detected in this series of tumors. In 25% of tumors, actionable mutations in PIK3CA , AKT1 , and ERBB2 were found in only 1 component. Altogether, our results confirm that most IDLC derive from invasive carcinoma of no special type, in which a population of cells lose E-cadherin and acquire a lobular phenotype. The frequency of CDH1 mutations in IDLC appears to be lower than in conventional invasive lobular carcinomas, suggesting the implication of alternative mechanisms of E-cadherin loss. Moreover, molecular heterogeneity between ductal and lobular areas suggests the need for molecular characterization of both components to guide targeted therapies.


Assuntos
Neoplasias da Mama , Carcinoma Ductal de Mama , Carcinoma Intraductal não Infiltrante , Carcinoma Lobular , Neoplasias da Mama/patologia , Caderinas/genética , Caderinas/metabolismo , Carcinoma Ductal de Mama/patologia , Carcinoma Intraductal não Infiltrante/patologia , Carcinoma Lobular/patologia , Cateninas , Classe I de Fosfatidilinositol 3-Quinases/genética , Feminino , Humanos , Hibridização in Situ Fluorescente
9.
Crit Care ; 26(1): 189, 2022 06 27.
Artigo em Inglês | MEDLINE | ID: mdl-35761404

RESUMO

BACKGROUND: Awake prone positioning (APP) reduces the intubation rate in COVID-19 patients treated by high-flow nasal cannula (HFNC). However, the lung aeration response to APP has not been addressed. We aimed to explore the lung aeration response to APP by lung ultrasound (LUS). METHODS: This two-center, prospective, observational study enrolled patients with COVID-19-induced acute hypoxemic respiratory failure treated by HFNC and APP. LUS score was recorded 5-10 min before, 1 h after APP, and 5-10 min after supine in the first APP session within the first three days. The primary outcome was LUS score changes in the first three days. Secondary outcomes included changes in SpO2/FiO2 ratio, respiratory rate and ROX index (SpO2/FiO2/respiratory rate) related to APP, and the rate of treatment success (patients who avoided intubation). RESULTS: Seventy-one patients were enrolled. LUS score decreased from 20 (interquartile range [IQR] 19-24) to 19 (18-21) (p < 0.001) after the first APP session, and to 19 (18-21) (p < 0.001) after three days. Compared to patients with treatment failure (n = 20, 28%), LUS score reduction after the first three days in patients with treatment success (n = 51) was greater (- 2.6 [95% confidence intervals - 3.1 to - 2.0] vs 0 [- 1.2 to 1.2], p = 0.001). A decrease in dorsal LUS score > 1 after the first APP session was associated with decreased risk for intubation (Relative risk 0.25 [0.09-0.69]). APP daily duration was correlated with LUS score reduction in patients with treatment success, especially in dorsal lung zones (r = - 0.76; p < 0.001). CONCLUSIONS: In patients with acute hypoxemic respiratory failure due to COVID-19 and treated by HFNC, APP reduced LUS score. The reduction in dorsal LUS scores after APP was associated with treatment success. The longer duration on APP was correlated with greater lung aeration. Trial registration This study was prospectively registered on clinicaltrials.gov on April 22, 2021. Identification number NCT04855162 .


Assuntos
COVID-19 , Insuficiência Respiratória , COVID-19/complicações , COVID-19/terapia , Humanos , Intubação Intratraqueal/efeitos adversos , Pulmão/diagnóstico por imagem , Decúbito Ventral/fisiologia , Estudos Prospectivos , Insuficiência Respiratória/etiologia , Insuficiência Respiratória/terapia , Vigília
10.
Sci Total Environ ; 826: 154027, 2022 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-35217040

RESUMO

Notwithstanding the fact that microplastic fragments were encountered in the human stool, little effort has been geared towards elucidating the impact of chemical additives upon the human health. In this work, standardized bioaccessibility tests under both fasting and fed conditions are herein applied to the investigation of human oral bioaccessibility of plastic additives and monomers (i.e. eight phthalate esters (PAEs) and bisphenol A (BPA)) in low-density polyethylene (LDPE) and polyvinyl chloride (PVC) microplastics. The generation of phthalate monoesters is evaluated in the time course of the bioaccessibility tests. Maximum gastric and gastrointestinal bioaccessibility fractions are obtained for dimethyl phthalate, diethyl phthalate and BPA, within the range of 55-83%, 40-68% and 37-67%, respectively, increasing to 56-92% and 41-70% for dimethyl phthalate and diethyl phthalate, respectively, whenever their hydrolysis products are considered. Bioaccessibility fractions of polar PAEs are dependent upon the physicochemical characteristics of the microplastics, with greater bioaccessibility for the rubbery polymer (LDPE). With the method herein proposed, oral bioaccessible pools of moderately to non-polar PAEs can be also accurately assessed for risk-assessment explorations, with values ranging from 1.8% to 32.2%, with again significantly larger desorption percentages for LDPE. Our results suggested that the highest gastric/gastrointestinal bioaccessibility of the eight PAEs and BPA is reached under fed-state gastrointestinal extraction conditions because of the larger amounts of surface-active biomolecules. Even including the bioaccessibility factor within human risk assessment/exposure studies to microplastics, concentrations of dimethyl phthalate, di-n-butyl phthalate and BPA exceeding 0.3% (w/w) may pose severe risks after oral uptake in contrast to the more hydrophobic congeners for which concentrations above 3% (w/w), except for diethylhexyl phthalate, would be tolerated.


Assuntos
Microplásticos , Ácidos Ftálicos , Compostos Benzidrílicos , Dibutilftalato , Ingestão de Alimentos , Ésteres , Jejum , Humanos , Fenóis , Plásticos , Polietileno
11.
Cardiovasc Res ; 118(16): 3250-3268, 2022 12 29.
Artigo em Inglês | MEDLINE | ID: mdl-34672341

RESUMO

AIMS: Interferon-stimulated gene 15 (ISG15) encodes a ubiquitin-like protein that induces a reversible post-translational modification (ISGylation) and can also be secreted as a free form. ISG15 plays an essential role as host-defence response to microbial infection; however, its contribution to vascular damage associated with hypertension is unknown. METHODS AND RESULTS: Bioinformatics identified ISG15 as a mediator of hypertension-associated vascular damage. ISG15 expression positively correlated with systolic and diastolic blood pressure and carotid intima-media thickness in human peripheral blood mononuclear cells. Consistently, Isg15 expression was enhanced in aorta from hypertension models and in angiotensin II (AngII)-treated vascular cells and macrophages. Proteomics revealed differential expression of proteins implicated in cardiovascular function, extracellular matrix and remodelling, and vascular redox state in aorta from AngII-infused ISG15-/- mice. Moreover, ISG15-/- mice were protected against AngII-induced hypertension, vascular stiffness, elastin remodelling, endothelial dysfunction, and expression of inflammatory and oxidative stress markers. Conversely, mice with excessive ISGylation (USP18C61A) show enhanced AngII-induced hypertension, vascular fibrosis, inflammation and reactive oxygen species (ROS) generation along with elastin breaks, aortic dilation, and rupture. Accordingly, human and murine abdominal aortic aneurysms showed augmented ISG15 expression. Mechanistically, ISG15 induces vascular ROS production, while antioxidant treatment prevented ISG15-induced endothelial dysfunction and vascular remodelling. CONCLUSION: ISG15 is a novel mediator of vascular damage in hypertension through oxidative stress and inflammation.


Assuntos
Aneurisma da Aorta Abdominal , Hipertensão , Camundongos , Humanos , Animais , Elastina/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Angiotensina II/metabolismo , Interferons/metabolismo , Leucócitos Mononucleares/metabolismo , Espessura Intima-Media Carotídea , Estresse Oxidativo , Hipertensão/induzido quimicamente , Hipertensão/genética , Hipertensão/metabolismo , Oxirredução , Aneurisma da Aorta Abdominal/induzido quimicamente , Aneurisma da Aorta Abdominal/genética , Aneurisma da Aorta Abdominal/prevenção & controle , Inflamação , Camundongos Endogâmicos C57BL
12.
Front Immunol ; 13: 1094172, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36643916

RESUMO

Introduction: Allergen-specific immunotherapy (AIT) is applied as treatment to rise tolerance in patients with food allergies. Although AIT is thoroughly used, the underlying epigenetic events related to tolerant induction are still unknown. Thus, we aim to investigate epigenetic changes that could be related to tolerance in dendritic cells (DCs) from anaphylactic mice to lipid transfer proteins, Pru p 3, in the context of a sublingual immunotherapy (SLIT) with a glycodendropeptide (D1ManPrup3) that has demonstrated tolerant or desensitization responses depending on the treatment dose. Methods: Changes in DNA methylation in CpG context were determined comparing Sensitized (Antigen-only) animals and two groups receiving SLIT with the D1ManPrup3 nanostructure (D1ManPrup3-SLIT): Tolerant (2nM D1ManPrup3) and Desensitized (5nM D1ManPrup3), against anaphylactic animals. DNA from lymph nodes-DCs were isolated and then, Whole Genome Bisulphite Sequencing was performed to analyze methylation. Results: Most differentially methylated regions were found on the area of influence of gene promoters (DMPRs). Compared to the Anaphylactic group, the highest value was found in Desensitized mice (n = 7,713 DMPRs), followed by Tolerant (n = 4,091 DMPRs) and Sensitized (n = 3,931 DMPRs) mice. Moreover, many of these epigenetic changes were found in genes involved in immune and tolerance responses (Il1b, Il12b, Il1a, Ifng, and Tnf) as shown by functional enrichment (DCs regulation, B cell-mediated immunity, and effector mechanisms). Discussion: In conclusion, different doses of D1ManPrup3-SLIT induce different DNA methylation changes, which are reflected in the induction of distinct responses, tolerance, or desensitization.


Assuntos
Anafilaxia , Hipersensibilidade Alimentar , Imunoterapia Sublingual , Animais , Camundongos , Metilação , Alérgenos , Dessensibilização Imunológica
13.
Front Pharmacol ; 12: 788850, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34887769

RESUMO

The synthesis and antioxidant, antinociceptive and antiedematogenic activities of sulfonamides derived from carvacrol-a druglike natural product-are reported. The compounds showed promising antioxidant activity, and sulfonamide derived from morpholine (S1) demonstrated excellent antinociceptive and antiedematogenic activities, with no sedation or motor impairment. The mechanism that underlies the carvacrol and derived sulfonamides' relieving effects on pain has not yet been fully elucidated, however, this study shows that the antinociceptive activity can be partially mediated by the antagonism of glutamatergic signaling. Compound S1 presented promising efficacy and was predicted to have an appropriate medicinal chemistry profile. Thus, derivative S1 is an interesting starting point for the design of new leads for the treatment of pain and associated inflammation and prooxidative conditions.

14.
Acta Neuropathol ; 142(6): 985-1001, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34618203

RESUMO

Amyotrophic lateral sclerosis is a progressive fatal neurodegenerative disease caused by loss of motor neurons and characterized neuropathologically in almost all cases by nuclear depletion and cytoplasmic aggregation of TDP-43, a nuclear RNA-binding protein (RBP). We identified ELAVL3 as one of the most downregulated genes in our transcriptome profiles of laser captured microdissection of motor neurons from sporadic ALS nervous systems and the most dysregulated of all RBPs. Neuropathological characterizations showed ELAVL3 nuclear depletion in a great percentage of remnant motor neurons, sometimes accompanied by cytoplasmic accumulations. These abnormalities were common in sporadic cases with and without intermediate expansions in ATXN2 and familial cases carrying mutations in C9orf72 and SOD1. Depletion of ELAVL3 occurred at both the RNA and protein levels and a short protein isoform was identified, but it is not related to a TDP-43-dependent cryptic exon in intron 3. Strikingly, ELAVL3 abnormalities were more frequent than TDP-43 abnormalities and occurred in motor neurons still with normal nuclear TDP-43 present, but all neurons with abnormal TDP-43 also had abnormal ELAVL3. In a neuron-like cell culture model using SH-SY5Y cells, ELAVL3 mislocalization occurred weeks before TDP-43 abnormalities were seen. We interrogated genetic databases, but did not identify association of ELAVL3 genetic structure with ALS. Taken together, these findings suggest that ELAVL3 is an important RBP in ALS pathogenesis acquired early and the neuropathological data suggest that it is involved by loss of function rather than cytoplasmic toxicity.


Assuntos
Esclerose Lateral Amiotrófica/metabolismo , Esclerose Lateral Amiotrófica/patologia , Proteína Semelhante a ELAV 3/metabolismo , Neurônios Motores/metabolismo , Núcleo Celular/metabolismo , Humanos
15.
J Cell Biol ; 220(9)2021 09 06.
Artigo em Inglês | MEDLINE | ID: mdl-34347016

RESUMO

Cholesterol metabolism operates autonomously within the central nervous system (CNS), where the majority of cholesterol resides in myelin. We demonstrate that TDP-43, the pathological signature protein for amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD), influences cholesterol metabolism in oligodendrocytes. TDP-43 binds directly to mRNA of SREBF2, the master transcription regulator for cholesterol metabolism, and multiple mRNAs encoding proteins responsible for cholesterol biosynthesis and uptake, including HMGCR, HMGCS1, and LDLR. TDP-43 depletion leads to reduced SREBF2 and LDLR expression, and cholesterol levels in vitro and in vivo. TDP-43-mediated changes in cholesterol levels can be restored by reintroducing SREBF2 or LDLR. Additionally, cholesterol supplementation rescues demyelination caused by TDP-43 deletion. Furthermore, oligodendrocytes harboring TDP-43 pathology from FTD patients show reduced HMGCR and HMGCS1, and coaggregation of LDLR and TDP-43. Collectively, our results indicate that TDP-43 plays a role in cholesterol homeostasis in oligodendrocytes, and cholesterol dysmetabolism may be implicated in TDP-43 proteinopathies-related diseases.


Assuntos
Colesterol/metabolismo , Proteínas de Ligação a DNA/genética , Demência Frontotemporal/genética , Bainha de Mielina/metabolismo , Oligodendroglia/metabolismo , Proteína de Ligação a Elemento Regulador de Esterol 2/genética , Animais , Proteínas de Ligação a DNA/deficiência , Modelos Animais de Doenças , Feminino , Lobo Frontal/metabolismo , Lobo Frontal/patologia , Demência Frontotemporal/metabolismo , Demência Frontotemporal/patologia , Perfilação da Expressão Gênica , Regulação da Expressão Gênica , Humanos , Hidroximetilglutaril-CoA Sintase/genética , Hidroximetilglutaril-CoA Sintase/metabolismo , Metabolismo dos Lipídeos/genética , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Bainha de Mielina/patologia , Oligodendroglia/patologia , Organoides/metabolismo , Organoides/patologia , Cultura Primária de Células , Receptores de LDL/genética , Receptores de LDL/metabolismo , Transdução de Sinais , Medula Espinal/metabolismo , Medula Espinal/patologia , Proteína de Ligação a Elemento Regulador de Esterol 2/metabolismo , Lobo Temporal/metabolismo , Lobo Temporal/patologia
16.
Curr Top Med Chem ; 21(13): 1167-1185, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34218788

RESUMO

BACKGROUND: Chalcones and dihydrochalcones present potent inhibition of acetylcholinesterase, currently considered the most efficient approach for symptomatic treatment of Alzheimer's disease. OBJECTIVE: The present study aimed to explore the potential benefits of 2',6'-dihydroxy-4'-methoxy dihydrochalcone on the cognitive deficits of animals submitted to the streptozotocin-induced Alzheimer's model, as well as evaluating the possible mechanisms of action. METHODS: Learning and memory functions of different groups of animals were submitted to the streptozotocin-induced Alzheimer's model (STZ 2.5 mg/mL, i.c.v.) and subsequently treated with 2',6'-dihydroxy-4'-methoxy dihydrochalcone (DHMDC) administered at doses of 5, 15, and 30 mg/kg (p.o.), respectively. Rivastigmine (0,6 mg/kg, i.p.) and vehicle were evaluated in aversive memory test (inhibitory avoidance test) and spatial memory test (object recognition test). Molecular docking simulations were performed to predict the binding mode of DHMDC at the peripheral site of AChE, to analyze noncovalent enzyme-ligand interactions. DFT calculations were carried out to study well-known acetylcholinesterase inhibitors and DHMDC. RESULTS: DHMDC markedly increased the learning and memory of mice. STZ caused a significant decline of spatial and aversive memories in mice, attenuated by DHMDC (15 and 30 mg/kg). Furthermore, STZ conspicuously increased lipid peroxidation and compromised the antioxidant levels in mice brains. DHMDC pretreatment significantly increased GSH activity and other oxidative stress markers and decreased TBARS level in the brain of STZ administered mice. AChE activity was significantly decreased by DHMDC in the brain of mice. CONCLUSION: The results together point out that DHMDC may be a useful drug in the management of dementia.


Assuntos
Doença de Alzheimer/tratamento farmacológico , Chalconas/farmacologia , Inibidores da Colinesterase/farmacologia , Transtornos Cognitivos/tratamento farmacológico , Fármacos Neuroprotetores/farmacologia , Acetilcolinesterase/metabolismo , Doença de Alzheimer/induzido quimicamente , Animais , Chalconas/química , Inibidores da Colinesterase/química , Transtornos Cognitivos/induzido quimicamente , Teoria da Densidade Funcional , Masculino , Camundongos , Simulação de Acoplamento Molecular , Fármacos Neuroprotetores/química , Estreptozocina , Relação Estrutura-Atividade
17.
Neurogenetics ; 22(4): 343-346, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34296368

RESUMO

Allan-Herndon-Dudley is an X-linked recessive syndrome caused by pathogenic variants in the SLC16A2 gene. Clinical manifestations are a consequence of impaired thyroid metabolism and aberrant transport of thyroid hormones to the brain. Carrier females are generally asymptomatic and may show subtle symptoms of the disease. We describe a female with a complete Allan-Herndon-Dudley phenotype, carrying a de novo 543-kb deletion of the X chromosome. The deletion encompasses exon 1 of the SLC16A2 gene and JPX and FTX genes; it is known that the latter two genes participate in the X-inactivation process upregulating XIST gene expression. Subsequent studies in the patient demonstrated the preferential expression of the X chromosome with the JPX and FTX deletion.


Assuntos
Deficiência Intelectual Ligada ao Cromossomo X/genética , Deficiência Intelectual Ligada ao Cromossomo X/patologia , Hipotonia Muscular/genética , Hipotonia Muscular/patologia , Atrofia Muscular/genética , Atrofia Muscular/patologia , Mutação/genética , Inativação do Cromossomo X/genética , Encéfalo/patologia , Criança , Feminino , Humanos , Deficiência Intelectual Ligada ao Cromossomo X/diagnóstico , Transportadores de Ácidos Monocarboxílicos/genética , Hipotonia Muscular/diagnóstico , Atrofia Muscular/diagnóstico , Fenótipo , Simportadores/genética
18.
JACC Case Rep ; 3(1): 34-38, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34317464

RESUMO

Coronary artery fistulas are rare coronary abnormalities. Most of these fistulas have a congenital origin, and only a few are acquired. We report the case of a patient with late-acquired multiple coronary fistulas secondary to a stab wound, diagnosed in the setting of ischemic heart failure secondary to coronary steal syndrome. (Level of Difficulty: Intermediate.).

19.
Allergy ; 76(10): 3183-3193, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-33784407

RESUMO

BACKGROUND: Amoxicillin (AX) is nowadays the ß-lactam that more frequently induces immediate allergic reactions. Nevertheless, diagnosis of AX allergy is occasionally challenging due to risky in vivo tests and non-optimal sensitivity of in vitro tests. AX requires protein haptenation to form multivalent conjugates with increased size to be immunogenic. Knowing adduct structural features for promoting effector cell activation would help to improve in vitro tests. We aimed to identify the optimal structural requirement in specific cellular degranulation to AX using well-precised nanoarchitectures of different lengths. METHOD: We constructed eight Bidendron Antigens (BiAns) based on polyethylene glycol (PEG) linkers of different lengths (600-12,000 Da), end-coupled with polyamidoamine dendrons that were terminally multi-functionalized with amoxicilloyl (AXO). In vitro IgE recognition was studied by competitive radioallergosorbent test (RAST) and antibody-nanoarchitecture complexes by transmission electron microscopy (TEM). Their allergenic activity was evaluated using bone marrow-derived mast cells (MCs) passively sensitized with mouse monoclonal IgE against AX and humanized RBL-2H3 cells sensitized with polyclonal antibodies from sera of AX-allergic patients. RESULTS: All BiAns were recognized by AX-sIgE. Dose-dependent activation responses were observed in both cellular assays, only with longer structures, containing spacers in the range of PEG 6000-12,000 Da. Consistently, greater proportion of immunocomplexes and number of antibodies per complex for longer BiAns were visualized by TEM. CONCLUSIONS: BiAns are valuable platforms to study the mechanism of effector cell activation. These nanomolecular tools have demonstrated the importance of the adduct size to promote effector cell activation in AX allergy, which will impact for improving in vitro diagnostics.


Assuntos
Hipersensibilidade a Drogas , Hipersensibilidade Imediata , Amoxicilina , Animais , Hipersensibilidade a Drogas/diagnóstico , Humanos , Imunoglobulina E , Camundongos , Penicilinas
20.
Environ Pollut ; 272: 115992, 2021 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-33246769

RESUMO

The unified bioaccessibility method (UBM) was harnessed to assess in vitro oral bioaccessibility pools of dialkyl phthalate congeners (with methyl, -ethyl, -butylbenzyl, -n-butyl, -2-ethylhexyl, and -n-octyl moieties) and bisphenol A at the 17 µg g-1 level in beach sand contaminated with polyethylene microplastics. A variety of sample preparation approaches prior to the analysis of the UBM gastrointestinal extracts, including traditional methods (protein precipitation, liquid-liquid extraction, and solid-phase extraction) and dispersive liquid-liquid microextraction (DLLME) were comprehensively evaluated for clean-up and analyte enrichment. DLLME was chosen among all tested approaches on account of the high extraction efficiency (73-95%, excluding bis(2-ethylhexyl)phthalate and di-n-octyl phthalate), high sample throughput (∼7 min per set of samples), and environmental friendliness as demonstrated by the analytical eco-scale score of 83, and the green analytical procedure index pictogram with green/yellow labeling. The release of the less hydrophobic plastic-laden compounds (dimethyl phthalate, diethyl phthalate and bisphenol A) from the contaminated sample into the body fluids was significant, with bioaccessibility values ranging from 30 to 70%, and from 43 to 74% in gastric and gastrointestinal fluids, respectively, and with relative standard deviation < 17% in all cases. The majority of the compounds were leached during gastric digestion, likely as the combined action of the low pH and the gastric enzymes. The risk exposure analysis revealed that accumulation/concentration in the body fluids is potentially relevant for dimethyl phthalate, diethyl phthalate and bisphenol A, with relative accumulation ratios ranging from 1.1 ± 0.1 to 2.6 ± 0.4. The average daily intake values for the suite of compounds, corrected with the bioaccessibility fraction, ranged from 60 to 430 ng kg of body weight-1·day-1, in all cases, far below the tolerable daily intakes, thus indicating the lack of children health risk by ingestion of microplastic-laden sand with elevated concentrations of plasticizers.


Assuntos
Disruptores Endócrinos , Ácidos Ftálicos , Criança , Humanos , Microplásticos , Extratos Vegetais , Plásticos , Areia
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