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1.
Artigo em Inglês | MEDLINE | ID: mdl-38727975

RESUMO

Daphnia spinulata Birabén, 1917 is an endemic cladoceran species, frequent in the zooplankton communities of the shallow lakes of the Pampean region of Argentina. These lakes have varying salinity levels and, being located in agricultural areas, are frequently subject to pesticide pollution. This study aimed to determine the effects of the herbicide glyphosate (Panzer Gold®) in combination with different salinity levels on the biological parameters of D. spinulata and its recovery ability after a short exposure. Three types of assays were performed: an acute toxicity test, a chronic assessment to determine survival, growth and reproduction, and recovery assays under optimal salinity conditions (1 g L-1). The LC50-48 h of glyphosate was 7.5 mg L-1 (CL 3.15 to 11.72). Longevity and the number of offspring and clutches were significantly reduced due to the combined exposure of glyphosate and increased salinity. The timing of the first offspring did not recover after glyphosate exposure. Our results reveal that D. spinulata is sensitive to the herbicide Panzer Gold® at concentrations well below those indicated in the safety data sheet of this commercial formulation, which causes stronger negative effects in conditions of higher salinity. Further research is needed to shed light on the sensitivity of this cladoceran to glyphosate and its variability under other interactive stress factors.

2.
Foods ; 13(7)2024 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-38611283

RESUMO

The total phenolic, flavonoid, and anthocyanin contents were evaluated in 11 cultivars of Argentinian roses of different colors. HPLC-ESI-QTOF/MS was used to identify the components where ellagic and quinic acids, quercetin, and kaempferol glycosylated derivatives were found. The phenolic contents ranged from 78.8 ± 3.2 to 203.4 ± 3.1 mg GAE/g dw, the flavonoid content ranged from 19.1 ± 3.8 to 125.9 ± 6.5 mg QE/g dw, and the anthocyanin content ranged from less than 0.01 to 5.8 ± 0.1 mg CE/g dw. The dark red cultivars exhibited the greatest levels of the analyzed compounds and of the antioxidant activities, even higher than those of certain plants known for their high phenolic contents and antioxidant activity. Moreover, the addition of these extracts decreased the population of L. innocua and P. aeruginosa to undetectable levels 24 h after inoculation. Rose petal extracts, mainly those with a dark red color, can be used as natural additives in food, feed, and cosmetics, as they contain a high proportion of bioactive compounds with antioxidant and antimicrobial effects.

3.
Metallomics ; 16(2)2024 02 07.
Artigo em Inglês | MEDLINE | ID: mdl-38337175

RESUMO

Steroids that take part in the pathways of human steroidogenesis are involved in many biological mechanisms where they interact with calcium. In the present work, the binding selectivities and affinities for calcium of progestagens, mineralocorticoids, androstagens, and estrogens were studied by Electrospray Ionization-Mass Spectrometry (ESI-MS). The adduct profile of each steroid was characterized by high resolution and tandem mass spectrometry. The relative stability of the most important adducts was studied by threshold collision induced dissociation, E1/2. Doubly-charged steroid-calcium complexes [nM + Ca]2+ with n = 1-6 were predominant in the mass spectra. The adduct [5M + Ca]2+ was the base peak for most 3-keto-steroids, while ligands bearing hindered ketones or α-hydroxy-ketones also yielded [nM + Ca + mH2O]2+ with n = 3-4 and m = 0-1. Principal component analysis allowed us to spot the main differences and similarities in the binding behavior of these steroids. The isomers testosterone and dehydroepiandrosterone, androstanolone and epiandrosterone, and 17-α-hydroxyprogesterone and 11-deoxycorticosterone showed remarkable differences in their adduct profiles. Computational modeling of representative adducts was performed by density functional theory methods. The possible binding modes at low and high numbers of steroid ligands were determined by calcium Gas Phase Affinity, and through modeling of the complexes and comparison of their relative stabilities, in agreement with the experimental results.


Assuntos
Cálcio , Espectrometria de Massas por Ionização por Electrospray , Humanos , Cálcio/química , Espectrometria de Massas por Ionização por Electrospray/métodos , Espectrometria de Massas em Tandem/métodos , Esteroides , Cetonas
4.
Gene Ther ; 31(3-4): 105-118, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37752346

RESUMO

Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disease that affects motor neurons, causing progressive muscle weakness and respiratory failure. The presence of an expanded hexanucleotide repeat in chromosome 9 open reading frame 72 (C9ORF72) is the most frequent mutation causing familial ALS and frontotemporal dementia (FTD). To determine if suppressing expression of C9ORF72 gene products can reduce toxicity, we designed a set of artificial microRNAs (amiRNA) targeting the human C9ORF72 gene. Here we report that an AAV9-mediated amiRNA significantly suppresses expression of the C9ORF72 mRNA, protein, and toxic dipeptide repeat proteins generated by the expanded repeat in the brain and spinal cord of C9ORF72 transgenic mice.


Assuntos
Esclerose Lateral Amiotrófica , MicroRNAs , Doenças Neurodegenerativas , Animais , Humanos , Camundongos , Esclerose Lateral Amiotrófica/genética , Esclerose Lateral Amiotrófica/terapia , Proteína C9orf72/genética , Proteína C9orf72/metabolismo , Dipeptídeos/genética , Dipeptídeos/metabolismo , Expansão das Repetições de DNA/genética , Camundongos Transgênicos , MicroRNAs/genética , Proteínas/genética , Proteínas/metabolismo
5.
iScience ; 26(11): 108109, 2023 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-37867936

RESUMO

The host-microbiome associations occurring on the skin of vertebrates significantly influence hosts' health. However, the factors mediating their interactions remain largely unknown. Herein, we used integrated technical and ecological frameworks to investigate the skin metabolites sustaining a beneficial symbiosis between tree frogs and bacteria. We characterize macrocyclic acylcarnitines as the major metabolites secreted by the frogs' skin and trace their origin to an enzymatic unbalance of carnitine palmitoyltransferases. We found that these compounds colocalize with bacteria on the skin surface and are mostly represented by members of the Pseudomonas community. We showed that Pseudomonas sp. MPFS isolated from frogs' skin can exploit acylcarnitines as its sole carbon and nitrogen source, and this metabolic capability is widespread in Pseudomonas. We summarize frogs' multiple mechanisms to filter environmental bacteria and highlight that acylcarnitines likely evolved for another function but were co-opted to provide nutritional benefits to the symbionts.

6.
Int J Mol Sci ; 24(18)2023 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-37762579

RESUMO

Oxidative stress-mediated damage is often a downstream result of Parkinson's disease (PD), which is marked by sharp decline in dopaminergic neurons within the nigrostriatal regions of the brain, accounting for the symptomatic motor deficits in patients. Regulating the level of oxidative stress may present a beneficial approach in preventing PD pathology. Here, we assessed the efficacy of a nicotinamide adenine phosphate (NADPH) oxidase (NOX) inhibitor, an exogenous reactive oxygen species (ROS) regulator synthesized by Aptabio therapeutics with the specificity to NOX-1, 2 and 4. Utilizing N27 rat dopaminergic cells and C57Bl/6 mice, we confirmed that the exposures of alpha-synuclein preformed fibrils (PFF) induced protein aggregation, a hallmark in PD pathology. In vitro assessment of the novel compound revealed an increase in cell viability and decreases in cytotoxicity, ROS, and protein aggregation (Thioflavin-T stain) against PFF exposure at the optimal concentration of 10 nM. Concomitantly, the oral treatment alleviated motor-deficits in behavioral tests, such as hindlimb clasping, rotarod, pole, nesting and grooming test, via reducing protein aggregation, based on rescued dopaminergic neuronal loss. The suppression of NOX-1, 2 and 4 within the striatum and ventral midbrain regions including Substantia Nigra compacta (SNc) contributed to neuroprotective/recovery effects, making it a potential therapeutic option for PD.


Assuntos
Doença de Parkinson , Humanos , Camundongos , Ratos , Animais , Doença de Parkinson/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Agregados Proteicos , alfa-Sinucleína/metabolismo , Encéfalo/metabolismo , Parte Compacta da Substância Negra/metabolismo , Neurônios Dopaminérgicos/metabolismo , Modelos Animais de Doenças , Camundongos Endogâmicos C57BL
7.
Antioxidants (Basel) ; 12(3)2023 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-36978929

RESUMO

The effect of freeze and hot air drying methods on the retention of total phenolics, antioxidant activity (AA), and color of different cultivars of rose petals was analyzed. Both methods similarly preserved the phenolic content and AA, while freeze drying showed better red color retention. Furthermore, the conditions of total phenolics and AA extraction from two rose cultivars, Lovely Red and Malu, were optimized by response surface methodology through a Box-Behnken design. The solvent exhibited a major effect on the total phenolic content (TPC) and AA. The selected parameters were ethanol 38%, 75 °C, and 30 min. Under these conditions, the predicted values for Lovely Red were 189.3 mg GA/g dw (TPC) and 535.6 mg Trolox/g dw (AA), and those for Malu were 108.5 mg GA/g dw (TPC) and 320.7 mg Trolox/g dw (AA). The experimental values were close to the predicted values, demonstrating the suitability of the model. Ultrasound-assisted extraction increased the AA of the extracts but not the TPC. Fifteen compounds were identified in the Lovely Red cultivar, with no differences between the two drying methods. The results obtained suggest that the analyzed cultivars, particularly the red ones, can be considered a natural source of powerful antioxidant compounds.

8.
Chem Biodivers ; 20(4): e202300021, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36943774

RESUMO

Chemical investigation of the extract of the macroscopic fungus Beenakia informis led to the isolation of a previously unreported γ-pyrone and two new isoprenylated cyclohexanoids, together with speciocin N. Their structures were elucidated spectroscopically and the absolute configuration was determined by comparison of the experimental vs. calculated ECD curves. Three of the compounds showed very good to moderate activity against phytopathogenic fungi.


Assuntos
Antifúngicos , Basidiomycota , Antifúngicos/farmacologia , Antifúngicos/química , Pironas/química , Estrutura Molecular , Fungos
9.
Peptides ; 159: 170900, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36336169

RESUMO

Amphibians have a great diversity of bioactive peptides in their skin. The cDNA prepro-peptide sequencing allowed the identification of five novel mature peptides expressed in the skin of Boana pulchella, four with similar sequences to hylin peptides having a cationic amphipathic-helical structure. Whole mature peptides and some of their fragments were chemically-synthesized and tested against Gram-positive and Gram-negative bacterial strains. The mature peptide hylin-Pul3 was the most active, with a MIC= 14 µM against Staphylococcus aureus. Circular dichroism assays indicated that peptides are mostly unstructured in buffer solutions. Still, adding large unilamellar vesicles composed of dimyristoyl phosphatidylcholine and dimyristoylphosphatidylglycerol increased the α-helix content of novel hylins. These results demonstrate the strong influence of the environment on peptide conformation and highlight its significance while addressing the pharmacology of peptides and their biological function in frogs.


Assuntos
Anuros , Peptídeos , Animais , Sequência de Aminoácidos , Peptídeos/farmacologia , Peptídeos/química , Lipídeos , Dicroísmo Circular
10.
Nat Prod Bioprospect ; 12(1): 26, 2022 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-35831516

RESUMO

The Antarctic fungus Cadophora malorum produces previously undescribed cyclic heptapeptides (cadophorin A and B) containing an anthranilic acid residue. The planar structure of these peptides was determined by high-resolution mass spectrometry combined with extensive 1D and 2D NMR spectroscopy. The absolute configuration of the amino acids was determined by Marfey's method, with HPLC analysis of FDVA (Nα-(2,4-dinitro-5-fluorphenyl)-L-valinamide) derivatives making use of a PFP column. Remarkably, cadophorin 2 possesses both the uncommon D-Ile and D-allo-Ile in its structure. The peptides have metal binding properties as shown by LCMS with post column addition of metal salt solutions. These results were supported by DFT calculations.

11.
Int J Mol Sci ; 23(8)2022 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-35457082

RESUMO

Parkinson's disease (PD) is a progressive neurodegenerative motor disorder without an available therapeutic to halt the formation of Lewy bodies for preventing dopaminergic neuronal loss in the nigrostriatal pathway. Since oxidative-stress-mediated damage has been commonly reported as one of the main pathological mechanisms in PD, we assessed the efficacy of a novel NOX inhibitor from AptaBio Therapeutics (C-6) in dopaminergic cells and PD mouse models. The compound reduced the cytotoxicity and enhanced the cell viability at various concentrations against MPP+ and α-synuclein preformed fibrils (PFFs). Further, the levels of ROS and protein aggregation were significantly reduced at the optimal concentration (1 µM). Using two different mouse models, we gavaged C-6 at two different doses to the PD sign-displaying transgenic mice for 2 weeks and stereotaxically PFF-injected mice for 5 weeks. Our results demonstrated that both C-6-treated mouse models showed alleviated motor deficits in pole test, hindlimb clasping, crossbeam, rotarod, grooming, and nesting analyses. We also confirmed that the compound treatment reduced the levels of protein aggregation, along with phosphorylated-α-synuclein, in the striatum and ventral midbrain and further dopaminergic neuronal loss. Taken together, our results strongly suggest that NOX inhibition can be a potential therapeutic target for PD.


Assuntos
Doença de Parkinson , alfa-Sinucleína , Animais , Modelos Animais de Doenças , Dopamina/metabolismo , Neurônios Dopaminérgicos/metabolismo , Camundongos , Camundongos Transgênicos , Degeneração Neural/patologia , Doença de Parkinson/metabolismo , Agregados Proteicos , alfa-Sinucleína/metabolismo
12.
Biochim Biophys Acta Proteins Proteom ; 1870(2): 140745, 2022 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-34906734

RESUMO

Bacteriophage endolysins are crucial for progeny release at the end of the lytic cycle. Mycobacteriophage's genomes carry a lysin A essential gene, whose product cleaves the peptidoglycan (PG) layer and a lysin B, coding for an esterase, that cleaves the linkage between the mycolic acids and the arabinogalactan-PG complex. Lysin A mycobacteriophage proteins are highly modular and in gp29 (LysA) of phage TM4 three distinctive domains were identified. By bioinformatics analysis the central module was previously found to be similar to an amidase-2 domain family with an N-acetylmuramoyl -L-alanine amidase activity. We demonstrated experimentally that purified LysA is able to lyse a suspension of Micrococcus lysodeikticus and can promote cell lysis when expressed in E. coli and Mycobacterium smegmatis. After incubation of LysA with MDP (Muramyl dipeptide, N-acetyl-muramyl-L-alanyl-D-isoglutamine) we detected the presence of N-acetylmuramic acid (NAcMur) and L-Ala- D- isoGlutamine (L-Ala-D-isoGln) corroborating the proposed muramidase activity of this enzyme. This protein was stabilized at acidic pH in the presence of Zn consistent with the increase of the enzymatic activity under these conditions. By homology modeling, we predicted that the Zn ion is coordinated by His 226, His 335, and Asp 347 and we also identified the amino acid Glu 290 as the catalytic residue. LysA activity was completely abolished in derived mutants on these key residues, suggesting that the PG hydrolysis solely relies on the central domain of the protein.


Assuntos
Endopeptidases/metabolismo , Micobacteriófagos/metabolismo , N-Acetil-Muramil-L-Alanina Amidase/metabolismo , Peptidoglicano/metabolismo , Proteínas Virais/metabolismo , Biologia Computacional/métodos , Endopeptidases/química , Escherichia coli/metabolismo , Galactanos , Hidrólise , Espectrometria de Massas/métodos , Micrococcus/metabolismo , Ácidos Murâmicos/metabolismo , Mycobacterium smegmatis/metabolismo , Proteínas Virais/química
13.
Acta ortop. bras ; 29(3): 153-158, Aug. 2021. tab, graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1278217

RESUMO

ABSTRACT Objective: To evaluate and compare anatomical measurements of C7, T1 and T2 vertebrae in children from 3 to 12 years of age to provide useful epidemiological data for determining the safe anatomical margin for transpedicular and translaminar fixation with screws in this population. Methods: This observational retrospective cross-sectional study evaluated 76 computed tomography scans obtained over 6 months, analyzing the following parameters: the angle of attack, length, thickness and diameter of the pedicle; and the angle of attack, length and thickness of the lamina. Results: The lamina length and thickness, as well as pedicle length varied in size according to age. Although the angle of attack was similar across different ages, age-dependent variation occurred in the T1 vertebra. Conclusion: Screws with a 3.5 mm diameter are safe to use in the C7 and T2 pedicles, while the T1 pedicle allows the introduction of larger screws ranging from 3.5-4.5 mm in diameter. In the lamina, 3.5 mm screws are safe for use only in children older than 7 years. However, each case should be analyzed individually, with the present study not aiming to replace the preoperative use of CT. Level of Evidence III, Retrospective comparative study.


RESUMO Objetivo: Avaliar e comparar as medidas anatômicas das vértebras C7, T1 e T2 em crianças de 3 a 12 anos de modo a determinar margens seguras para fixação transpedicular e translaminar com parafusos nessa população. Métodos: Estudo transversal retrospectivo observacional. Um total de 76 tomografias computadorizadas foram analisadas em um período de 6 meses. Os seguintes parâmetros foram analisados: ângulo de ataque, comprimento, espessura e diâmetro do pedículo, comprimento e espessura da lâmina. Resultados: O comprimento e espessura da lâmina bem como o comprimento do pedículo aumenta em tamanho conforme a idade. Enquanto o ângulo de ataque permanece estável conforme variação de idade; variação dependente da idade ocorre somente na vértebra T1. Conclusão: Parafusos com diâmetro de 3.5mm podem ser inseridos de maneira segura nos pedículos de C7 e T2. Já no pedículo de T1 pode-se inserir parafusos com medidas de 3.5 a 4.5mm de diâmetro de maneira segura. Na lâmina, parafusos de 3.5mm podem ser usados de maneira segura somente em crianças maiores de 7 anos. No entanto, cada caso deve ser analisado de maneira individualizada, e o presente estudo não objetivo substituir o uso de tomografia computadorizada no pré-operatório. Nível de Evidência III, Estudo Comparativo Retrospectivo.

14.
Acta Ortop Bras ; 29(3): 153-158, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34290563

RESUMO

OBJECTIVE: To evaluate and compare anatomical measurements of C7, T1 and T2 vertebrae in children from 3 to 12 years of age to provide useful epidemiological data for determining the safe anatomical margin for transpedicular and translaminar fixation with screws in this population. METHODS: This observational retrospective cross-sectional study evaluated 76 computed tomography scans obtained over 6 months, analyzing the following parameters: the angle of attack, length, thickness and diameter of the pedicle; and the angle of attack, length and thickness of the lamina. RESULTS: The lamina length and thickness, as well as pedicle length varied in size according to age. Although the angle of attack was similar across different ages, age-dependent variation occurred in the T1 vertebra. CONCLUSION: Screws with a 3.5 mm diameter are safe to use in the C7 and T2 pedicles, while the T1 pedicle allows the introduction of larger screws ranging from 3.5-4.5 mm in diameter. In the lamina, 3.5 mm screws are safe for use only in children older than 7 years. However, each case should be analyzed individually, with the present study not aiming to replace the preoperative use of CT. Level of Evidence III, Retrospective comparative study.


OBJETIVO: Avaliar e comparar as medidas anatômicas das vértebras C7, T1 e T2 em crianças de 3 a 12 anos de modo a determinar margens seguras para fixação transpedicular e translaminar com parafusos nessa população. MÉTODOS: Estudo transversal retrospectivo observacional. Um total de 76 tomografias computadorizadas foram analisadas em um período de 6 meses. Os seguintes parâmetros foram analisados: ângulo de ataque, comprimento, espessura e diâmetro do pedículo, comprimento e espessura da lâmina. RESULTADOS: O comprimento e espessura da lâmina bem como o comprimento do pedículo aumenta em tamanho conforme a idade. Enquanto o ângulo de ataque permanece estável conforme variação de idade; variação dependente da idade ocorre somente na vértebra T1. CONCLUSÃO: Parafusos com diâmetro de 3.5mm podem ser inseridos de maneira segura nos pedículos de C7 e T2. Já no pedículo de T1 pode-se inserir parafusos com medidas de 3.5 a 4.5mm de diâmetro de maneira segura. Na lâmina, parafusos de 3.5mm podem ser usados de maneira segura somente em crianças maiores de 7 anos. No entanto, cada caso deve ser analisado de maneira individualizada, e o presente estudo não objetivo substituir o uso de tomografia computadorizada no pré-operatório. Nível de Evidência III, Estudo Comparativo Retrospectivo.

15.
Clinics (Sao Paulo) ; 76: e2741, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34008773

RESUMO

OBJECTIVES: To determine the rate of and main risk factors for postoperative infection in cancer patients who underwent spine surgery in the last 5 years in order to determine whether there is an association between postoperative infection and increased mortality during hospitalization. METHODS: All cancer patients who underwent surgical procedures between January 2015 and December 2019 at a single hospital specializing in spine cancer surgery were analyzed. The primary outcome of interest was postoperative infection. Bivariate logistic regression was used to estimate the odds ratio and 95% confidence interval for each variable in relation to the occurrence of infection. RESULTS: We evaluated 324 patients, including 176 men (54.3%) and 148 women (45.7%) with a mean age of 56 years. The incidence of postoperative infection was 20.37%. Of the 324 patients, 39 died during hospitalization (12%). CONCLUSIONS: Surgical time greater than 4 hours, surgical instrumented levels greater than 6, and an Eastern Cooperative Oncology Group of 3 or 4 were associated with an increased risk of postoperative infection, but these factors did not lead to an increase in mortality during hospitalization.


Assuntos
Neoplasias , Coluna Vertebral , Feminino , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Neoplasias/cirurgia , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/etiologia , Estudos Retrospectivos , Fatores de Risco , Coluna Vertebral/cirurgia
16.
ChemMedChem ; 16(12): 1945-1955, 2021 06 17.
Artigo em Inglês | MEDLINE | ID: mdl-33682316

RESUMO

In this work, we describe how stereochemically complex polycyclic compounds can be generated by applying a synthetic sequence comprising an intramolecular Ugi reaction followed by a Pictet-Spengler cyclization on steroid-derived scaffolds. The resulting compounds, which combine a fragment derived from a natural product and a scaffold not found in nature. are both structurally distinct and globally similar to natural products at the same time, and interrogate an alternative region of the chemical space. One of the new compounds showed significant antiproliferative activity on HepG2 cells through a caspase-independent cell-death mechanism, an appealing feature when new antitumor compounds are searched.


Assuntos
Antineoplásicos/farmacologia , Produtos Biológicos/farmacologia , Caspases/metabolismo , Isoquinolinas/farmacologia , Piperazinas/farmacologia , Esteroides/farmacologia , Antineoplásicos/síntese química , Antineoplásicos/química , Produtos Biológicos/síntese química , Produtos Biológicos/química , Morte Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Células Hep G2 , Humanos , Isoquinolinas/síntese química , Isoquinolinas/química , Estrutura Molecular , Piperazinas/síntese química , Piperazinas/química , Estereoisomerismo , Esteroides/síntese química , Esteroides/química
17.
Nat Prod Res ; 35(21): 3945-3954, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32308028

RESUMO

Five new lanostanoid triterpenes were isolated from the extract of R. microporus. Three of the metabolites (1-3) present a Δ8,9 skeleton with an uncommon keto functionality at C-1. Another compound (4) has an unprecedented rearranged skeleton in which methyl-19 was transposed to C-1, with conjugated double bonds at Δ1-10 and Δ8-9. All of the compounds have hydroxylated or furane-cyclized side-chains. The structures were elucidated by spectroscopic methods, and the absolute configuration of the hydroxyl-bearing carbon in the side chain of compound 5 was established in silico. The metabolites were evaluated for their antifungal activity and the bioactivity as agonist/antagonists of the liver X receptors (LXRs). Compound 4 presents antifungal activity and compounds 3 and 5 are the agonists of LXRs.


Assuntos
Triterpenos , Fungos , Lanosterol/análogos & derivados , Estrutura Molecular , Polyporales , Triterpenos/farmacologia
18.
Phytochem Anal ; 31(5): 606-615, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32045084

RESUMO

INTRODUCTION: An efficient characterisation of metabolites is a crucial task in many aspects of basic research, such as the de-replication of crude extracts in natural products chemistry or the tentative identification of compounds in untargeted metabolomics. OBJECTIVE: The goal of this work is the evaluation of the reaction with phenylhydrazine for the derivatisation post-column in situ of carbonyl-containing compounds in liquid chromatography-mass spectrometry (LC-MS). MATERIALS AND METHODS: LC-MS was performed using electrospray, Atmospheric Pressure Chemical Ionisation (APCI) or Atmospheric Pressure Photoionization (APPI) as ionisation techniques. The post-column addition of phenylhydrazine was done through a syringe pump via a T-junction before entrance to the ion source. RESULTS: A variety of natural products having carbonyl groups, such as cycloartanes, steroids, cardenolides and other terpenoids, were analysed by this method. In the case of compounds with non-hindered aldehyde or keto groups, the main signals of the mass spectra were those corresponding to the phenylhydrazones. However, the spectra of compounds with hindered carbonyl groups displayed mainly those signals corresponding to the product of the nucleophilic addition adduct of phenylhydrazine to the carbonyl, which is the first step of the derivatisation process. Finally, those compounds with conjugated ketones did not react with phenylhydrazine. This methodology was applied in the analysis of crude natural extracts. CONCLUSION: The results show that in situ derivatisation of carbonyl compounds in the ionisation source was achieved, yielding the typical derivatives of carbonyl compounds with phenylhydrazine.


Assuntos
Produtos Biológicos , Espectrometria de Massas em Tandem , Pressão Atmosférica , Cromatografia Líquida , Metabolômica , Espectrometria de Massas por Ionização por Electrospray
19.
Rev. Soc. Odontol. La Plata ; 30(59): 9-20, 2020. ilus, tab, graf
Artigo em Espanhol | LILACS | ID: biblio-1223943

RESUMO

El 81,3% de una encuesta realizada a 96 ortodoncistas y ortopedistas calificados y técnicos radiólogos consultados informan que ubican la cabeza del paciente en una posición ideal, subjetiva del profesional instruido que lo asiste, ya que muchas de sus fotografías y telerradiografías no son posiciones naturales de la cabeza genuinas. Se ha utilizado la vertical verdadera como parámetro para mediciones, todas angulares, para definir la disposición ánteroposterior del punto A´ (de construcción) para el cuerpo del labio superior, el punto Pg´para el mentón, el Labrale superior y el Labrale inferior para el bermellón de cada labio, con la finalidad de planificar correcciones ortopédicas, ortodóncicas u ortodóncicas-quirúrgicas de acuerdo a la anomalía detectada (AU)


Assuntos
Humanos , Masculino , Feminino , Postura/fisiologia , Cefalometria/métodos , Cabeça , Ortopedia/métodos , Valores de Referência , Antropometria/métodos , Inquéritos Epidemiológicos , Queixo/anatomia & histologia , Fotografia Dentária , Lábio/anatomia & histologia , Má Oclusão/terapia , Má Oclusão/diagnóstico por imagem
20.
Front Microbiol ; 10: 3114, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-32117083

RESUMO

Cryptococcus species are responsible for important systemic mycosis and are estimated to cause millions of new cases annually. The available therapy is limited due to the high toxicity and the increasing rates of yeast resistance to antifungal drugs. Popularly known as "sucará," Xylosma prockia (Turcz.) Turcz. (Salicaceae) is a native plant from Brazil with little information on its pharmacological potential. In this work, we evaluated in vitro anticryptococcal effects of the leaf ethanolic extract of X. prockia and its fractions against Cryptococcus gattii and Cryptococcus neoformans. We also evaluated phenotypic alterations caused by ethyl acetate fraction (EAF) (chosen according to its biological results). The liquid chromatography-mass spectrometry (LC-MS) analysis of EAF demonstrated the presence of phenolic metabolites that belong to three structurally related groups as majority compounds: caffeoylquinic acid, coumaroyl-glucoside, and caffeoyl-glucoside/deoxyhexosyl-caffeoyl glucoside derivatives. The minimum inhibitory concentration (MIC) values against C. gattii and C. neoformans ranged from 8 to 64 mg/L and from 0.5 to 8 mg/L, for ethanolic extract and EAF, respectively. The EAF triggered an oxidative burst and promoted lipid peroxidation. EAF also induced a reduction of ergosterol content in the pathogen cell membrane. These effects were not associated with alterations in the cell surface charge or in the thermodynamic fingerprint of the molecular interaction between EAF and the yeasts evaluated. Cytotoxic experiments with peripheral blood mononuclear cells (PBMCs) demonstrated that EAF was more selective for yeasts than was PBMCs. The results may provide evidence that X. prockia leaf extract might indeed be a potential source of antifungal agents.

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