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1.
Br J Haematol ; 204(3): 892-897, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38013238

RESUMO

Recently modified diagnostic criteria for chronic myelomonocytic leukaemia (CMML) have lowered the cut-off for absolute monocytosis. In the largest series to date, we have analysed 313 CMML patients, including 104 with oligomonocytic (OM)-CMML. Five-year survival was longer for OM-CMML than for other patients (p < 0.001). Multivariate analysis identified OM-CMML as a favourable prognostic factor (HR 0.58; p = 0.002). The 5-year cumulative incidence of progression to classical CMML was 47%. Older age and transfusion dependence were adverse prognostic factors for OM-CMML. Our results support the inclusion of OM-CMML in the CMML category as a subtype with superior outcomes.


Assuntos
Leucemia Mielomonocítica Crônica , Humanos , Leucemia Mielomonocítica Crônica/diagnóstico , Leucocitose , Prognóstico
2.
Br J Haematol ; 205(1): 256-267, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38811025

RESUMO

European LeukemiaNet refined their risk classification of acute myeloid leukaemia (AML) in 2022 (ELN 2022) according to the two new myeloid classifications published the same year. We have retrospectively assessed the prognostic value of the ELN 2022 in 120 AML patients undergoing allogeneic haematopoietic cell transplantation (allo-HCT), including 99 in first complete response (CR1) from 2011 to 2021 in our centre. Adverse risk patients (Adv) presented inferior outcome in terms of overall survival (OS) and leukaemia-free survival (LFS) (OS [p = 0.003], LFS [p = 0.02]), confirmed in multivariate analysis (hazard ratio [HR] for OS = 2.00, p = 0.037). These results were also seen in patients allografted in CR1. Further analysis identified a subgroup named adverse-plus (AdvP), including complex karyotype, MECOM(EVI1) rearrangements and TP53 mutations, with worse outcomes than the rest of groups of patients, including the Adv (HR for OS: 3.14, p < 0.001, HR for LFS: 3.36, p < 0.001), with higher 2-year cumulative incidence of relapse (p < 0.001). Notably, within this analysis, the outcome of Adv and intermediate patients were similar. These findings highlight the prognostic value of ELN 2022 in patients undergoing allo-HCT, which can be improved by the recognition of a poor genetic subset (AdvP) within the Adv risk group.


Assuntos
Transplante de Células-Tronco Hematopoéticas , Leucemia Mieloide Aguda , Humanos , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/terapia , Leucemia Mieloide Aguda/mortalidade , Masculino , Feminino , Pessoa de Meia-Idade , Adulto , Prognóstico , Idoso , Estudos Retrospectivos , Transplante Homólogo , Adolescente , Adulto Jovem , Mutação , Medição de Risco/métodos , Intervalo Livre de Doença , Proteína do Locus do Complexo MDS1 e EVI1/genética
3.
Small ; 20(8): e2305690, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37840406

RESUMO

A Mg-cell with P2-Na2/3 Ni1/3 Mn2/3 O2 layered oxide cathode provides novel reaction mechanism not observed in Na-cells. The sodium/vacancy ordering and Jahn-Teller effects are suppressed with the insertion of magnesium ion. The Mg-cell exhibits different features when operating between 4.5 and 0.15 V and 3.9 and 0.15 V versus Mg2+ /Mg. To analyze the structural and chemical changes during Mg insertion, the cathode is first charged to obtain the Na1/3 Ni1/3 Mn2/3 O2 compound, which is formally accompanied by an oxidation from Ni2+ to Ni3+ . As structure models Mg1/6 Na1/3 Ni1/3 Mn2/3 O2 and Mg1/12 Na1/2 Ni1/3 Mn2/3 O2 are utilized with a large 2 3 a $2\sqrt 3 a$ × 2 3 a $2\sqrt 3 a$ supercell. On discharge, the Mg-cell exhibits a multistep profile which reaches ≈100 mA h g-1 with the valence change from Ni3+ to Ni2+ . Such profile is quite different from its sodium counterpart (230 mA h g-1 ) which exhibits the sodium/vacancy ordering and deleterious presence of Mn3+ . Depending on how the two interlayer spacings are filled by Na and Mg the "staged," "intermediated," and "average" models are analyzed for Mgy Na8 Ni8 Mn16 O48 supercell. This fact suggests differences in the cell performance when Mg is used as counter electrode providing some tips to improve the structure engineering on cathode materials.

4.
Bioorg Med Chem Lett ; 106: 129770, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38677560

RESUMO

We have previously reported the total synthesis and structure-activity relationships (SAR) of 2-prenylated benzopyrans with PPAR agonist activity. Herein, we have described the synthesis and PPAR activity of 2-prenylated benzopyrans and 2-prenylated quinolines. The benzopyran nucleus was generated via enamine-catalyzed Kabbe condensation, and the quinoline nucleus via Friedländer condensation. Results demonstrated that both benzopyran (5a) and quinoline (4b) derivatives bearing a γ,δ-unsaturated ester displayed a pan-PPAR agonism. They were full PPARα agonists, but showed different preferences for PPARγ and PPARß/δ activation. It was noteworthy that quinoline 4b displayed full hPPARα activation (2-fold than WY-14,643), weak PPARß/δ and partial PPARγ activation. In addition, quinoline 4b showed anti-inflammatory effects on macrophages by reducing LPS-induced expression of both MCP-1 and IL-6. Therefore, 4b emerges as a first-in-class promising hit compound for the development of potential therapeutics aimed at treating metabolic syndrome, metabolic dysfunction-associated fatty liver disease (MAFLD), and its associated cardiovascular comorbidities.


Assuntos
Síndrome Metabólica , Quinolinas , Síndrome Metabólica/tratamento farmacológico , Síndrome Metabólica/metabolismo , Quinolinas/química , Quinolinas/farmacologia , Quinolinas/síntese química , Relação Estrutura-Atividade , Humanos , Receptores Ativados por Proliferador de Peroxissomo/metabolismo , Receptores Ativados por Proliferador de Peroxissomo/agonistas , Estrutura Molecular , Lipopolissacarídeos/farmacologia , Lipopolissacarídeos/antagonistas & inibidores , Anti-Inflamatórios/síntese química , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/química , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Relação Dose-Resposta a Droga , Benzopiranos/farmacologia , Benzopiranos/síntese química , Benzopiranos/química , Animais , Camundongos
5.
Small ; 19(12): e2206010, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36634973

RESUMO

Magnesium driven reaction in olivine-type MgMn0.5 Zn0.5 SiO4 structure is subject of study by experimental tests and density functional theory (DFT) calculations. The partial replacement of Mn in Oh sites by other divalent metal such as Zn to get MgMn0.5 Zn0.5 SiO4 cathode is successfully developed by a simple sol-gel method. Its comparison with the well-known MgMnSiO4 olivine-type structure with (Mg)M1 (Mn)M2 SiO4 cations distribution serves as the basis of this study to understand the structure, and the magnesium extraction/insertion properties of novel olivine-type (Mg)M1 (Mn0.5 Zn0.5 )M2 SiO4 composition. This work foresees to extend the study to others divalent elements in olivine-type (Mg)M1 (Mn0.5 M0.5 )M2 SiO4 structure with M = Fe, Ca, Mg, and Ni by DFT calculations. The obtained results indicate that the energy density can be attuned between 520 and 440 W h kg-1 based on two properties of atomic weight and redox chemistry. The presented results commit to open new paths toward development of cathodes materials for Mg batteries.

6.
Pharmacol Res ; 187: 106638, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36586645

RESUMO

BACKGROUND AND PURPOSE: Selective peroxisome proliferator-activated receptors (PPARs) are widely used to treat metabolic complications; however, the limited effect of PPARα agonists on glucose metabolism and the adverse effects associated with selective PPARγ activators have stimulated the development of novel pan-PPAR agonists to treat metabolic disorders. Here, we synthesized a new prenylated benzopyran (BP-2) and evaluated its PPAR-activating properties, anti-inflammatory effects and impact on metabolic derangements. EXPERIMENTAL APPROACH: BP-2 was used in transactivation assays to evaluate its agonism to PPARα, PPARß/δ and PPARγ. A parallel-plate flow chamber was employed to investigate its effect on TNFα-induced leukocyte-endothelium interactions. Flow cytometry and immunofluorescence were used to determine its effects on the expression of endothelial cell adhesion molecules (CAMs) and chemokines and p38-MAPK/NF-κB activation. PPARs/RXRα interactions were determined using a gene silencing approach. Analysis of its impact on metabolic abnormalities and inflammation was performed in ob/ob mice. KEY RESULTS: BP-2 displayed strong PPARα activity, with moderate and weak activity against PPARß/δ and PPARγ, respectively. In vitro, BP-2 reduced TNFα-induced endothelial ICAM-1, VCAM-1 and fractalkine/CX3CL1 expression, suppressed mononuclear cell arrest via PPARß/δ-RXRα interactions and decreased p38-MAPK/NF-κB activation. In vivo, BP-2 improved the circulating levels of glucose and triglycerides in ob/ob mice, suppressed T-lymphocyte/macrophage infiltration and proinflammatory markers in the liver and white adipose tissue, but increased the expression of the M2-like macrophage marker CD206. CONCLUSION AND IMPLICATIONS: BP-2 emerges as a novel pan-PPAR lead candidate to normalize glycemia/triglyceridemia and minimize inflammation in metabolic disorders, likely preventing the development of further cardiovascular complications.


Assuntos
Doenças Metabólicas , PPAR delta , PPAR beta , Camundongos , Animais , PPAR gama/metabolismo , PPAR alfa/metabolismo , PPAR beta/metabolismo , Fator de Necrose Tumoral alfa , Benzopiranos , NF-kappa B , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/uso terapêutico , Inflamação/tratamento farmacológico
7.
Phys Chem Chem Phys ; 25(23): 15600-15623, 2023 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-37272358

RESUMO

Developing new and sustainable batteries is essential for modern society. Both cationic doping (e.g. transition metals) and anionic doping (F-, O2-, S2-, PO43-, etc.) can be employed to improve the electrochemical behaviour of electrode materials. Herein, the anion-doping, or multianion approach, is comprehensively reviewed and investigated. It is observed that the optimized compositions of some electrode materials can involve metastable or transient states. Going beyond the inductive effect, we propose that the simultaneous use of several kinds of anions in the framework of the same host material could create a sort of energized state in the electrode material, and this could be interpreted within the "entatic state" principle which is used in coordination chemistry, catalysis, and bioinorganic chemistry. In this new hypothesis, the coordination of a cation by several anions with different properties can modify the local structure and it could enhance the electrochemical performance; this could be particularly useful for the future post-lithium batteries. The multianion approach can also be applied to electrolytes and interfaces. Finally, new theoretical calculations on multianion-based materials (carbonophosphates, thiocarbonates and Mg8Mn16O32-zFz) are reported here, highlighting the need for further research in the coordination sphere of metal-ligand systems for tuning battery properties.

8.
Bioorg Med Chem ; 53: 116532, 2022 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-34863066

RESUMO

2-Prenylated benzopyrans represent a class of natural and synthetic compounds showing a wide range of significant activities. Polycerasoidol is a natural prenylated benzopyran isolated from the stem bark of Polyalthia cerasoides (Annonaceae) that exhibits dual PPARα/γ agonism and an anti-inflammatory effect by inhibiting mononuclear leukocyte adhesion to the dysfunctional endothelium. Herein, we report the synthesis of three new series of prenylated benzopyrans containing one (series 1), two (series 2, "polycerasoidol" analogs) and three (series 3, "trans-δ-tocotrienolic acid" analogs) isoprenoid units in the hydrocarbon side chain at the 2-position of the chroman-6-ol (6-hydroxy-dihydrobenzopyran) scaffold. Isoprenoid moieties were introduced through a Grignard reaction sequence, followed by Johnson-Claisen rearrangement and subsequent Wittig olefination. hPPAR transactivation activity and the structure activity relationships (SAR) of eleven novel synthesized 2-prenylated benzopyrans were explored. PPAR transactivation activity demonstrated that the seven-carbon side chain analogs (series 1) displayed selectivity for hPPARα, while the nine-carbon side chain analogs (polycerasoidol analogs, series 2) did so for hPPARγ. The side chain elongation to 11 or 13 carbons (series 3) resulted in weak dual PPARα/γ activation. Therefore, 2-prenylated benzopyrans of seven- and nine-carbon side chain (polycerasoidol analogs) are good lead compounds for developing useful candidates to prevent cardiovascular diseases associated with metabolic disorders.


Assuntos
Anti-Inflamatórios não Esteroides/farmacologia , Benzopiranos/farmacologia , PPAR alfa/agonistas , PPAR gama/agonistas , Vitamina E/análogos & derivados , Anti-Inflamatórios não Esteroides/síntese química , Anti-Inflamatórios não Esteroides/química , Benzopiranos/síntese química , Benzopiranos/química , Relação Dose-Resposta a Droga , Humanos , Estrutura Molecular , Relação Estrutura-Atividade , Vitamina E/síntese química , Vitamina E/química , Vitamina E/farmacologia
9.
Sensors (Basel) ; 22(21)2022 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-36365849

RESUMO

In this work, ZnO nanoparticle resistive sensors decorated with rare earths (REs; including Er, Tb, Eu and Dy) were used at room temperature to detect atmospheric pollutant gases (NO2, CO and CH4). Sensitive films were prepared by drop casting from aqueous solutions of ZnO nanoparticles (NPs) and trivalent RE ions. The sensors were continuously illuminated by ultraviolet light during the detection processes. The effect of photoactivation of the sensitive films was studied, as well as the influence of humidity on the response of the sensors to polluting gases. Comparative studies on the detection properties of the sensors showed how the presence of REs increased the response to the gases detected. Low concentrations of pollutant gases (50 ppb NO2, 1 ppm CO and 3 ppm CH4) were detected at room temperature. The detection mechanisms were then discussed in terms of the possible oxidation-reduction (redox) reaction in both dry and humid air atmospheres.


Assuntos
Poluentes Ambientais , Óxido de Zinco , Dióxido de Nitrogênio/análise , Raios Ultravioleta , Temperatura , Gases/análise
10.
Chemistry ; 27(49): 12599-12609, 2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-34165219

RESUMO

Rechargeable magnesium batteries attract lots of attention because of their high safety and low cost compared to lithium batteries, and it is needed to develop more efficient electrode materials. Although MgMn2 O4 is a promising material for the positive electrode in Mg rechargeable batteries, it usually exhibits poor cyclability. To improve the electrochemical behavior, we have prepared nanoparticles of MgMn2-y Fey O4 . The XRD results have confirmed that when Mn3+ (Jahn-Teller ion) ions are replaced by Fe3+ (non-Jahn-Teller ion), the resulting MgMn2-y Fey O4 is a cubic phase. The structure and theoretical voltage are theoretically calculated by using the DFT method. The obtained samples have been chemically treated in acid solution for partial demagnesiation, and it is observed that the presence of iron inhibits the deinsertion of Mg through disproportionation and favors the exchange reaction. The electrochemical behavior in non-aqueous magnesium cells has been explored.

11.
Phytochem Anal ; 32(6): 1011-1026, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33738879

RESUMO

INTRODUCTION: Given the diversity of secondary metabolites produced by species of the genus Erythroxylum, in addition to the many methods that have already been described in the literature, modern screening and identification methodologies, such as dereplication, represent an efficient and quick strategy compared to the classic techniques linked to natural product research. OBJECTIVE: The objective of the present study was to determine the phenolic profiles obtained from three species of Erythroxylum (Erythroxylum pauferrense Plowman, Erythroxylum pulchrum A.St.-Hil. and Erythroxylum simonis Plowman) by dereplication using liquid chromatography coupled with ESI-MSn and HRESIMS. MATERIAL AND METHODS: Ethyl acetate and n-butanolic fractions from crude ethanolic extract of Erythroxylum species were analyzed by HPLC-ESI-MSn and HPLC-HRESIMS, in order to identify its corresponding compounds. Experiments were performed in negative ionization mode, and the metabolites were provisionally identified based on deprotonated molecules, molecular formulas, fragmentation patterns and literature data. The corresponding isolated compounds were characterized by 1 H and 13 C NMR spectroscopy. RESULTS: According to the dereplication method, it was possible to establish and compare the phenolic profile of the corresponding species by the assignment of 55 compounds, most of which were first described in these species and among which some were also new to the Erytroxylum genus. Additionally, nine compounds were isolated, including biphenyl-3,3',4,4'-tetraol, where the mass spectral data were not sufficient for their identification, and reported for the first time in the Erythroxylaceae family. CONCLUSION: This research contributes to the phytochemical knowledge of the Erythroxylum genus and demonstrates the importance of the dereplication method regarding the investigation of natural products, enabling accurate identification of the metabolites while avoiding the efforts and material expenses involved in the isolation of known compounds.


Assuntos
Erythroxylaceae , Espectrometria de Massas por Ionização por Electrospray , Cromatografia Líquida de Alta Pressão , Fenóis , Compostos Fitoquímicos , Extratos Vegetais
12.
J Sci Food Agric ; 101(7): 2828-2835, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33135178

RESUMO

BACKGROUND: Nowadays, the craft beer market is booming and the consumer trend for trying something new is increasing. Here, nine different treatments of a craft beer were realized in a pilot plant, studying fermentation and dry-hopping types. Quality parameters of the beer such as polyphenols, antioxidants, bitterness, colour and alcohol were analysed. In addition, an electronic nose was used to distinguish beer types. RESULTS: Results showed that dry hopping in maturation with warm temperature increased the bitterness from 33 to 40 IBUs. The treatment using two yeasts and two fermentation temperatures resulted in the highest antioxidant capacity of the beer (around 92%). Antioxidant activity was increased by late dry hopping using ale yeasts for fermenting. Principal component analysis performed with electronic nose data explained up to 97% of the total variability of the compounds in the study. CONCLUSIONS: Combined use of ale and lager yeasts seems to increase the antioxidant capacity and total polyphenol content of beer. Antioxidant activity is increased by late dry hopping. An electronic nose is a suitable device for discriminating the volatile profile complexity in beer. © 2020 Society of Chemical Industry.


Assuntos
Cerveja/análise , Microbiologia de Alimentos/métodos , Humulus/microbiologia , Antioxidantes/análise , Antioxidantes/metabolismo , Cerveja/microbiologia , Etanol/análise , Etanol/metabolismo , Fermentação , Humanos , Humulus/química , Humulus/classificação , Humulus/metabolismo , Valor Nutritivo , Polifenóis/análise , Polifenóis/metabolismo , Paladar , Leveduras/metabolismo
13.
Environ Monit Assess ; 193(12): 809, 2021 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-34783906

RESUMO

The use of biodiesel blends with petroleum diesel in vehicular engines demands the evaluation of the possible impacts and effects of the gases emitted from their combustion on the environment. Among studies on these questions, biomonitoring using lichens is a viable alternative, given their interactions with the elements dispersed in the atmosphere, as well as its sensitivity and capacity to retain contaminants. In this study, we analyzed the effects of gas emissions from the combustion of biodiesel mixture with petroleum diesel on Cladonia verticillaris thalli. Samples of the lichen (10 g) were exposed to the gases emitted by the exhaust of the generator engine during the combustion process of biodiesel mixtures to petroleum diesel (7% (B7), 10% (B10), 40% (B40), 50% (B50), and 70% (B70)). At 90 days after exposure, samples were analyzed for n-alkane profiles, thallus morphology, photosynthetic pigment contents, and secondary lichen metabolites (protocetraric and fumarprotocetraric acids). Sets B7 and B10 showed better resistance of the lichen to pollutants. Set B40 showed a high stress evidenced by the chain elongation of n-alkanes structure and high chlorophyll production, presenting high morphological damages when compared to the control sets, B7 and B10. The results showed significant reductions of n-alkanes profiles for mixtures with high concentrations of biodiesel (B50 and B70), as well as decreases in the chlorophyll content. These groups showed an increase in the synthesis of secondary metabolites, corroborating the hypothesis that high concentrations of biodiesel in the mixture with petroleum diesel have greater impacts on the lichen. Schematic model for demonstration of using the lichen Cladonia verticillaris as biomonitor of effects from gas emissions from the combustion of biodiesel blends with petroleum diesel by a stationary engine.


Assuntos
Biocombustíveis , Líquens , Ascomicetos , Biocombustíveis/análise , Conservação dos Recursos Naturais , Monitoramento Ambiental , Gasolina/análise , Emissões de Veículos/análise
14.
J Dairy Res ; 87(1): 117-122, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31948491

RESUMO

We analyzed the effects of growth of Penicillium commune, one of the most frequent fungal species associated with cheese, on the water diffusion and texture of hard and extra-hard cheeses. A total of 36 hard cheese blocks and 36 extra-hard cheese blocks were manufactured, salted at different levels (0.5, 1.25 and 2% w/w), and assigned to different treatments (control and inoculated). Cheese texture was analyzed using a penetration needle probe at 2 and 5 weeks after ripening. Firmness, defined as the maximum force detected in the penetration probe, was higher in both hard and extra-hard inoculated cheese blocks compared with the control. In addition, the presence of fungal growth on cheese rind increased the total work of penetration (a measure of resistance to probe penetration), but only in extra-hard cheeses, suggesting that the moisture of cheese might be affecting the growth capacities and performance of P. commune. The change in textural properties of cheeses was linked to desiccation of the upper 0.5-cm rind layer mediated by P. commune.


Assuntos
Queijo/microbiologia , Penicillium/metabolismo , Queijo/análise , Queijo/normas , Manipulação de Alimentos/métodos , Qualidade dos Alimentos , Dureza , Maleabilidade , Água/análise
15.
Sensors (Basel) ; 20(24)2020 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-33348560

RESUMO

This work presents the development of tin oxide nanofibers (NFs) and nanoribbons (NRs) sensors with graphene as a dopant for the detection of volatile organic compounds (VOCs) corresponding to different chronic diseases (asthma, chronic obstructive pulmonary disease, cystic fibrosis or diabetes). This research aims to determine the ability of these sensors to differentiate between gas samples corresponding to healthy people and patients with a disease. The nanostructures were grown by electrospinning and deposited on silicon substrates with micro-heaters integrated. The morphology of NFs and NRs was characterized by Scanning Electron Microscopy (SEM). A gas line was assembled and programmed to measure a wide range of gases (ethanol, acetone, NO and CO) at different concentrations simulating human breath conditions. Measurements were made in the presence and absence of humidity to evaluate its effect. The sensors were able to differentiate between the concentrations corresponding to a healthy person and a patient with one of the selected diseases. These were sensitive to biomarkers such as acetone and ethanol at low operating temperatures (with responses above 35%). Furthermore, CO and NO response was at high temperatures (above 5%). The sensors had a rapid response, with times of 50 s and recovery periods of about 10 min.


Assuntos
Testes Respiratórios , Grafite , Nanofibras , Nanotubos de Carbono , Compostos de Estanho , Compostos Orgânicos Voláteis/análise , Biomarcadores/análise , Gases/análise , Humanos
16.
Int J Mol Sci ; 22(1)2020 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-33379337

RESUMO

Translation elongation factor eIF5A binds to ribosomes to promote peptide bonds between problematic amino acids for the reaction like prolines. eIF5A is highly conserved and essential in eukaryotes, which usually contain two similar but differentially expressed paralogue genes. The human eIF5A-1 isoform is abundant and implicated in some cancer types; the eIF5A-2 isoform is absent in most cells but becomes overexpressed in many metastatic cancers. Several reports have connected eIF5A and mitochondria because it co-purifies with the organelle or its inhibition reduces respiration and mitochondrial enzyme levels. However, the mechanisms of eIF5A mitochondrial function, and whether eIF5A expression is regulated by the mitochondrial metabolism, are unknown. We analysed the expression of yeast eIF5A isoforms Tif51A and Tif51B under several metabolic conditions and in mutants. The depletion of Tif51A, but not Tif51B, compromised yeast growth under respiration and reduced oxygen consumption. Tif51A expression followed dual positive regulation: by high glucose through TORC1 signalling, like other translation factors, to promote growth and by low glucose or non-fermentative carbon sources through Snf1 and heme-dependent transcription factor Hap1 to promote respiration. Upon iron depletion, Tif51A was down-regulated and Tif51B up-regulated. Both were Hap1-dependent. Our results demonstrate eIF5A expression regulation by cellular metabolic status.


Assuntos
Nutrientes , Fatores de Iniciação de Peptídeos/metabolismo , Proteínas de Ligação a RNA/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/metabolismo , Transdução de Sinais , Aerobiose/efeitos dos fármacos , Carbono/farmacologia , Ciclo do Ácido Cítrico/efeitos dos fármacos , Regulação para Baixo/efeitos dos fármacos , Regulação para Baixo/genética , Fermentação/efeitos dos fármacos , Regulação Fúngica da Expressão Gênica/efeitos dos fármacos , Glucose/metabolismo , Heme/metabolismo , Ferro/metabolismo , Deficiências de Ferro , Lisina/análogos & derivados , Lisina/metabolismo , Alvo Mecanístico do Complexo 1 de Rapamicina/metabolismo , Análise do Fluxo Metabólico , Modelos Biológicos , Isoformas de Proteínas/metabolismo , Saccharomyces cerevisiae/efeitos dos fármacos , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/crescimento & desenvolvimento , Transdução de Sinais/efeitos dos fármacos , Regulação para Cima/efeitos dos fármacos , Regulação para Cima/genética , Fator de Iniciação de Tradução Eucariótico 5A
17.
J Nat Prod ; 82(10): 2721-2730, 2019 10 25.
Artigo em Inglês | MEDLINE | ID: mdl-31599155

RESUMO

This study represents the first phytochemical analysis of Stillingia loranthacea (S. loranthacea) and describes new terpenoids obtained from the root bark of this species. The fractionation of the hexane extract from the root bark led to the isolation of two new 28-nor-taraxarenes derivatives, loranthones A and B (1 and 2), four new tigliane diterpenes (5-8), three known tigliane diterpenes (9-11), and three known flexibilene diterpenes, tonantzitlolones A-C (12-14). The investigation of these compounds and the use of a molecular networking-based prioritization approach afforded two other new 28-nor-taraxarenes, loranthones C and D (3 and 4). The cytotoxicity of compounds 1, 2, and 5-14 was evaluated against Vero cells, and their 20% cytotoxic concentration (CC20) values varied from 8.7 to 328 µM; antiviral activity was tested against an epidemic Zika virus (ZIKV) strain circulating in Brazil. Six out of 12 compounds (2, 5, 9-11, and 14) exhibited significant antiviral effects against ZIKV. Specifically, compounds 2 and 5 offered the most promise as lead compounds as they had a 1.7 and 1.8 log10 TCID50/mL reduction in ZIKV replication, respectively. Together, the present findings have identified S. loranthacea terpenoids as potent anti-ZIKV inhibitors and pave the way to the development of possible new treatments against this devastating pathogen.


Assuntos
Diterpenos/isolamento & purificação , Euphorbiaceae/química , Triterpenos/isolamento & purificação , Replicação Viral/efeitos dos fármacos , Zika virus/efeitos dos fármacos , Animais , Chlorocebus aethiops , Diterpenos/química , Diterpenos/farmacologia , Espectroscopia de Ressonância Magnética , Triterpenos/química , Triterpenos/farmacologia , Células Vero , Zika virus/fisiologia
18.
J Plant Res ; 132(3): 405-417, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30864048

RESUMO

Previous studies have already highlighted the correlation between Sporisorium scitamineum pathogenicity and sugarcane polyamine accumulation. It was shown that high infectivity correlates with an increase in the amount of spermidine, spermine and cadaverine conjugated to phenols in the sensitive cultivars whereas resistant plants mainly produce free putrescine. However, these previous studies did not clarify the role of these polyamides in the disorders caused to the plant. Therefore, the purpose of this research is to clarify the effect of polyamines on the development of smut disease. In this paper, commercial polyamines were firstly assayed on smut teliospores germination. Secondly, effects were correlated to changes in endogenous polyamines after contact with defense sugarcane glycoproteins. Low concentrations of spermidine significantly activated teliospore germination, while putrescine had no activating effect on germination. Interestingly, it was observed that the diamine caused nuclear decondensation and breakage of the teliospore cell wall whereas the treatment of teliospores with spermidine did not induce nuclear decondensation or cell wall breakdown. Moreover, the number of polymerized microtubules increased in the presence of 7.5 mM spermidine but it decreased with putrescine which indicates that polyamines effects on Sporisorium scitamineum teliospore germination could be mediated through microtubules interaction. An increased production of polyamines in smut teliospores has been related to sugarcane resistance to the disease. Teliospores incubation with high molecular mass glycoproteins (HMMG) from the uninoculated resistant variety of sugarcane, Mayari 55-14, caused an increase of the insoluble fraction of putrescine, spermidine and spermine inside the teliospore cells. Moreover, the level of the soluble fraction of spermidine (S fraction) increased inside teliospores and the excess was released to the medium. The HMMG glycoproteins purified from Mayarí 55-14 plants previously inoculated with the pathogen significantly increased the levels of both retained and secreted soluble putrescine and spermidine. Polyamines levels did not increase in teliospores after incubation with HMMG produced by non resistant variety Barbados 42231 which could be related to the incapacity of these plants to defend themselves against smut disease. Thus, a hypothesis about the role of polyamines in sugarcane-smut interaction is explained.


Assuntos
Poliaminas Biogênicas/metabolismo , Glicoproteínas/metabolismo , Imunidade Vegetal , Saccharum/microbiologia , Esporos Fúngicos/metabolismo , Ustilaginales/metabolismo , Poliaminas Biogênicas/fisiologia , Glicoproteínas/fisiologia , Doenças das Plantas/imunologia , Doenças das Plantas/microbiologia , Putrescina/metabolismo , Putrescina/fisiologia , Saccharum/metabolismo , Espermidina/metabolismo , Espermidina/fisiologia , Espermina/metabolismo , Espermina/fisiologia , Ustilaginales/fisiologia
19.
Molecules ; 24(14)2019 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-31295814

RESUMO

Zornia brasiliensis Vogel (Leguminosae) is a species popularly known in Brazil as "urinária", "urinana", and "carrapicho", it is popularly used as a diuretic and in the treatment of venereal diseases. A specific methodology to obtain a saponin-enriched fraction and high-performance liquid chromatography coupled with diode array detection, ion trap mass spectrometry, and TOF-MS (HPLC-DAD-ESI-MS/MS) was applied for the analysis of triterpene saponins. The MS and MS/MS experiments were carried out by ionization in negative mode. Molecular mass and fragmentation data were used to support the structural characterization of the saponins. Based on retention times, high-resolution mass determination and fragmentation, 35 oleanane-triterpene saponins were tentatively identified in Z. brasiliensis.


Assuntos
Cromatografia Líquida de Alta Pressão , Fabaceae/química , Extratos Vegetais/análise , Saponinas/análise , Espectrometria de Massas por Ionização por Electrospray , Espectrometria de Massas em Tandem , Triterpenos/análise , Espectroscopia de Ressonância Magnética , Redes e Vias Metabólicas , Estrutura Molecular , Extratos Vegetais/química , Saponinas/química , Triterpenos/química
20.
Molecules ; 24(21)2019 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-31671588

RESUMO

Lamiaceae is one of the largest families of angiosperms and is classified into 12 subfamilies that are composed of 295 genera and 7775 species. It presents a variety of secondary metabolites such as diterpenes that are commonly found in their species, and some of them are known to be chemotaxonomic markers. The aim of this work was to construct a database of diterpenes and to use it to perform a chemotaxonomic analysis among the subfamilies of Lamiaceae, using molecular descriptors and self-organizing maps (SOMs). The 4115 different diterpenes corresponding to 6386 botanical occurrences, which are distributed in eight subfamilies, 66 genera, 639 different species and 4880 geographical locations, were added to SistematX. Molecular descriptors of diterpenes and their respective botanical occurrences were used to generate the SOMs. In all obtained maps, a match rate higher than 80% was observed, demonstrating a separation of the Lamiaceae subfamilies, corroborating with the morphological and molecular data proposed by Li et al. Therefore, through this chemotaxonomic study, we can predict the localization of a diterpene in a subfamily and assist in the search for secondary metabolites with specific structural characteristics, such as compounds with potential biological activity.


Assuntos
Bioprospecção , Diterpenos/classificação , Lamiaceae/classificação , Algoritmos , Bases de Dados como Assunto , Diterpenos/química , Aprendizado de Máquina , Filogenia
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