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1.
Toxicon ; 250: 108074, 2024 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-39154758

RESUMO

Cyanobacterial blooms are common events that releases secondary metabolites into water posing considerable threats to the environment, wildlife, and public health. Some of these metabolites, such as microcystin, have been extensively studied and associated with harmful effects in mammals and aquatic organisms, while the biological effects of others, like geosmin, remain much less investigated. Enhancing our understanding of cyanotoxins effects on organisms is especially relevant facing the complex scenarios projected due to global warming. The aim of this study was to assess the transcriptional modulation in whole zebrafish (Danio rerio) larvae (n = 9) in response to a 7-days immersion exposure to 3 µg L-1 MCLR or 5 µg L-1 geosmin. No mortality or differences in length gain were observed in zebrafish larvae exposed to environmentally realistic doses of both cyanotoxins. The exposure to MCLR and to geosmin caused the differential expression of 164 and 172 genes respectively, being 23 upregulated by MCLR and 98 upregulated by geosmin. Among the upregulated genes, 16 were shared, while 42 were shared among the downregulated genes. Over-representation analysis identified three enriched GO terms only among the genes upregulated by geosmin: organic hydroxy compound metabolic process (1901615), small molecule biosynthetic process (0044283), and lipid metabolic process (0006629). In fact, the expression of 12 of the 13 genes directly involved in the synthesis of cholesterol from acetyl-CoA was upregulated by geosmin. A chronic upregulation of cholesterol biosynthetic pathway is linked to several diseases and metabolic disorders, including alterations in sex-related hormones. Moreover, our results indicate that geosmin and MCLR acts through different mechanisms. Geosmin does not appear to provoke short-term adverse effects as MCLR but could disrupt the endocrine system by altering the lipid and steroid metabolism.


Assuntos
Larva , Microcistinas , Naftóis , Peixe-Zebra , Animais , Microcistinas/toxicidade , Larva/efeitos dos fármacos , Toxinas Marinhas/toxicidade
2.
J Chromatogr A ; 1731: 465174, 2024 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-39111195

RESUMO

The present work describes a quick, simple, and efficient method based on the use of layered double hydroxides (LDH) coupled to dispersive solid phase micro-extraction (DSPME) to remove α-naphthol (α-NAP) and ß-naphthol (ß-NAP) isomers from water samples. Three different LDHs (MgAl-LDH, NiAl-LDH, and CoAl-LDH) were used to study how the interlayer anion and molar ratio affected the removal performance. The critical factors in the DSPME procedure (pH, LDH amount, contact time) were optimized by the univariate method under the optimal conditions: pH, 4-8; LDH amount, 5 mg; and contact time, 2.5 min. The method can be successfully applied in real sample waters, removing NAP isomers even in ultra-trace concentrations. The large volume sample stacking (LVSS-CE) technique provides limits of detections (LODs) of 5.52 µg/L and 6.36 µg/L for α-naphthol and ß-naphthol, respectively. The methodology's precision was evaluated on intra- and inter-day repeatability, with %RSD less than 10% in all cases. The MgAl/Cl--LDH selectivity was tested in the presence of phenol and bisphenol A, with a removal rate of >92.80%. The elution tests suggest that the LDH MgAl/Cl--LDH could be suitable for pre-concentration of α-naphthol and ß-naphthol in future works.


Assuntos
Eletroforese Capilar , Limite de Detecção , Naftóis , Microextração em Fase Sólida , Poluentes Químicos da Água , Naftóis/química , Naftóis/análise , Naftóis/isolamento & purificação , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/isolamento & purificação , Poluentes Químicos da Água/química , Eletroforese Capilar/métodos , Microextração em Fase Sólida/métodos , Hidróxidos/química , Isomerismo , Reprodutibilidade dos Testes , Concentração de Íons de Hidrogênio
3.
Chirality ; 36(5): e23675, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38699899

RESUMO

This study describes the interaction of human serum albumin (HSA) with the binol derivative (R)-(+)-3,3'-dibromo-1,1'-bi-2-naphthol (R-BrB), which has its optical activity based on the prohibitive energetic barrier for conversion into the enantiomer (S)-(+)-3,3'-dibromo-1,1'-bi-2-naphthol (S-BrB). The objective was to assess the ability of HSA to differentiate axial enantiomers based on their binding efficiency and their impact on the CD spectra. We discovered that both enantiomers were effective ligands, and the CD signal disappeared when equimolar amounts of R-BrB and S-BrB were simultaneously added, indicating no preference for either enantiomer. The complexation resulted in a significant signal increase at 250 nm and a bathochromic effect at 370 nm. Molecular docking simulations were performed, and the lower energy pose of R-BrB was selected for DFT calculations. The theoretical CD spectra of free and complexed R-BrB were obtained and showed alterations corroborating the experimental results. By comparing the difference spectrum (HSA:R-BrB minus HSA) with the spectrum of free RBrB in water or ethyl alcohol, we concluded that the CD signal intensification was due to the increased solubilization of R-BrB upon binding to HSA.


Assuntos
Dicroísmo Circular , Simulação de Acoplamento Molecular , Naftóis , Albumina Sérica Humana , Dicroísmo Circular/métodos , Naftóis/química , Albumina Sérica Humana/química , Estereoisomerismo , Humanos , Teoria da Densidade Funcional , Simulação por Computador , Ligação Proteica
4.
An Acad Bras Cienc ; 96(1): e20230145, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38451597

RESUMO

In the last few years, the presence of geosmin (GEO) in water bodies has caused serious problems related to water consumption by the population. Many studies focus on its occurrence and detection, but little is discussed about the technologies for treatment and removal of this contaminant. In this way, the present work aims to present a bibliographic search and a bibliometric analysis carried out in the Web of Science database and in VOSviewer software about geosmin remediation, in the last 10 years. 100 articles were found, of which only one, from 2021, was a review. It was possible to assess that the subject has gained greater notoriety in the last 7 years, since the year 2016 marked the increase of publications on the subject, as well as an increasing number of citations. Among the most published countries is the People's Republic of China, with 53% of publications. Bibliometric analysis showed that GEO is directly related to 2-methylisoborneol (2-MIB), since both occur simultaneously in water bodies. In addition, it was possible to identify that adsorptive processes are the most used in the removal of these contaminants, followed by advanced oxidative processes and biological processes, in that order.


Assuntos
Bibliometria , Naftóis , Humanos , Adsorção , Água
5.
Langmuir ; 40(3): 1869-1877, 2024 01 23.
Artigo em Inglês | MEDLINE | ID: mdl-38194363

RESUMO

Characterization studies of 1-butyl-3-methyl-imidazolium bis(2-ethylhexyl) sulfosuccinate vesicles at different pH values have been carried out by using liquid surface tension, transmission electron microscopy, and dynamic light scattering. The results show that there are no vesicle changes in its size and negative Z potential at pH 3, 6, and 10. Furthermore, indomethacin and 1-naphthol, both pH-dependent, electroactive, and fluorescence probes, were used to further characterize the bilayer employing electrochemical and emission techniques. The partition of indomethacin and 1-naphthol between the water and bilayer pseudophases only occurs for the neutral species and does not happen for the anionic species because the highly negative Z bilayer potential prevents incorporation due to negative repulsion. For the neutral species, the partition constant values were evaluated by square wave voltammetry and emission spectroscopy. Finally, for the indomethacin incorporated into the vesicle bilayer at pH 3, the release profile was monitored over time at pH 6. It was found that a change in the pH values causes the complete release of indomethacin after 25 min, which led us to think that the vesicles presented in this work can be used as a pH-sensitive nanocarrier for neutral pH-sensitive drugs.


Assuntos
Indometacina , Naftóis , Succinatos , Espectrometria de Fluorescência , Concentração de Íons de Hidrogênio
6.
Food Res Int ; 173(Pt 2): 113375, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37803713

RESUMO

An increasing demand for fish products has led to an intensive aquaculture production in Brazil, and cultivation of fish constituted 860 × 103 tons in 2022, contributing to the 87% of total fish consumption. Nile tilapia constitutes almost half of the aquaculture production, and most tilapia farms use floating net cages. One of the major constraints of intensive fish production is production of off-flavors. Release of nutrients by the fish leads to deterioration of the water quality and stimulates growth of microorganisms, also including off-flavor producing species. The objective of this study was to determine levels of taste and odor compounds (geosmin, 2-MIB and a selection of volatile compounds) and their impact on the flavor quality of Nile tilapia produced in net cages in reservoirs in São Paulo State, Brazil. GC-MS analysis of fish and water from six different farms showed concentrations of geosmin in the water from 1 to 8 ng/L, while geosmin in fish flesh ranged from 40 to 750 ng/kg. The level of 2-MIB in water was 2 to 25 ng/L, and 0 to 800 ng/kg fish. The GC-MS analysis also revealed presence of more than 100 volatile organic compounds in the fish flesh, consisting of aldehydes, alcohols, benzene derivatives, hydrocarbons, ketones and few other compounds. Geosmin and 2-MIB related flavor notes were detected in all fish by a sensory panel, and a high correlation between the chemical and sensory analyses was found. The potential impact of the volatile organic compounds on the fish flavor is discussed. Analysis of the water quality in the reservoirs indicated that levels of geosmin and 2-MIB levels were highly influenced by the nutrient levels in the water.


Assuntos
Ciclídeos , Compostos Orgânicos Voláteis , Animais , Brasil , Naftóis/análise , Naftóis/química
7.
Environ Res ; 235: 116571, 2023 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-37467941

RESUMO

Over the years, humans have been continuously exposed to several compounds directly generated by industrial processes and/or present in consumed products. Polycyclic aromatic hydrocarbons (PAHs) are legacy pollutants ubiquitous in the environment and represent the main chemical pollutants in urban areas. Worldwide, studies that aim to understand the impacts of exposure to these chemicals have gained increasing prominence due to their potential toxicity profile, mainly concerning genotoxicity and carcinogenicity. Human biomonitoring (HB) is an analytical approach to monitoring population exposure to chemicals; however, these studies are still limited in Brazil. Thus, this work aimed to evaluate the exposure of Brazilian pregnant women to PAHs through HB studies. Besides, the risk characterization of this exposure was performed. For this purpose, urine samples from 358 Brazilian pregnant women were used to evaluate 11 hydroxylated metabolites of PAHs employing gas chromatography coupled to mass spectrometry. The 1OH-naphthol and 2OH-naphthol were detected in 100% of the samples and showed high levels, corresponding to 16.99 and 3.62 µg/g of creatinine, respectively. 2OH-fluorene (8.12 µg/g of creatinine) and 9OH-fluorene (1.26 µg/g of creatinine) were detected in 91% and 66% of the samples, respectively. Benzo(a)pyrene (BaP) metabolites were detected in more than 50% of the samples (0.58-1.26 µg/g of creatinine). A hazard index of 1.4 and a carcinogenic risk above 10-4 were found for BaP metabolites in the risk characterization. Therefore, our findings may indicate that exposure to PAHs poses a potential risk to pregnant women's health and a high probability of carcinogenic risk due to their exposure to BaP. Finally, this work shows the need for more in-depth studies to determine the sources of exposure and the implementation of health protection measures regarding the exposure of the Brazilian population to PAHs.


Assuntos
Poluentes Ambientais , Hidrocarbonetos Policíclicos Aromáticos , Humanos , Feminino , Gravidez , Hidrocarbonetos Policíclicos Aromáticos/urina , Monitoramento Biológico , Brasil , Gestantes , Monitoramento Ambiental/métodos , Naftóis/análise , Creatinina , Poluentes Ambientais/urina , Medição de Risco , Carcinógenos/análise , Fluorenos/análise
8.
Molecules ; 27(11)2022 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-35684556

RESUMO

Bovine mastitis is one of the most common diseases in dairy cows, and it causes significant economic losses in dairy industries worldwide. Gram-positive and Gram-negative bacteria can cause bovine mastitis, and many of them have developed antimicrobial resistance. There is an urgent need for novel therapeutic options to treat the disease. Larrea tridentata-derived compounds represent an important potential alternative treatment. The aim of the present study was to isolate and characterize antibacterial compounds from Larrea tridentata against multidrug-resistant bacteria associated with bovine mastitis. The L. tridentata hydroalcoholic extract (LTHE) exhibited antibacterial activity. The extract was subjected to a bipartition, giving an aqueous fraction (moderate antibacterial activity) and an organic fraction (higher antibacterial activity). Chromatographic separation of the organic fraction enabled us to obtain four active sub-fractions. Chemical analyses through HPLC techniques were conducted for the LTHE, fractions, and sub-fraction Ltc1-F3, from which we isolated two compounds, characterized by 1H and 13C NMR analyses. Compound nor-3 demethoxyisoguaiacin exhibited the best antibacterial activity against the evaluated bacteria (MIC: 0.01-3.12 mg/mL; MBC: 0.02-3.12 mg/mL). The results indicated that nor-3 demethoxyisoguaiacin can be used as an alternative treatment for multidrug-resistant bacteria associated with mastitis.


Assuntos
Larrea , Mastite Bovina , Animais , Antibacterianos/química , Bactérias , Bovinos , Feminino , Bactérias Gram-Negativas , Bactérias Gram-Positivas , Larrea/química , Mastite Bovina/tratamento farmacológico , Testes de Sensibilidade Microbiana , Naftóis , Extratos Vegetais/química
9.
Molecules ; 28(1)2022 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-36615207

RESUMO

BINOL derivatives have shown relevant biological activities and are important chiral ligands and catalysts. Due to these properties, their asymmetric synthesis has attracted the interest of the scientific community. In this work, we present an overview of the most efficient methods to obtain chiral BINOLs, highlighting the use of metal complexes and organocatalysts as well as kinetic resolution. Further derivatizations of BINOLs are also discussed.


Assuntos
Naftóis , Estereoisomerismo , Catálise , Ligantes
10.
J Chem Ecol ; 47(7): 597-613, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34232439

RESUMO

Melanin is a heteropolymer formed by the polymerization of phenolic and indolic compounds. It occurs in organisms across all biological kingdoms and has a range different of functions, thus indicating its important evolutionary role. The presence of melanin offers several protective advantages, including against ultraviolet radiation, traumatic damage, oxidative stress, extreme temperatures, and pressure. For many species of fungi, melanin also participates directly in the process of virulence and pathogenicity. These organisms can synthesize melanin in two main ways: using a substrate of endogenous origin, involving 1,8-dihydroxynaphthalene (DHN); alternatively, in an exogenous manner with the addition of L-3, 4-dihydroxyphenylalanine (L-DOPA or levodopa). As melanin is an amorphous and complex substance, its study requires expensive and inaccessible technologies and analyses are often difficult to perform with conventional biochemical techniques. As such, details about its chemical structure are not yet fully understood, particularly for nematophagous fungi that remain poorly studied. Thus, this review presents an overview of the different types of melanin, with an emphasis on fungi, and discusses the role of melanin in the biology and ecology of nematophagous fungi.


Assuntos
Fungos/metabolismo , Melaninas/metabolismo , Fungos/patogenicidade , Lacase/metabolismo , Levodopa/química , Levodopa/metabolismo , Melaninas/química , Monofenol Mono-Oxigenase/metabolismo , Naftóis/química , Naftóis/metabolismo , Policetídeo Sintases/metabolismo
11.
Malar J ; 20(1): 279, 2021 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-34162381

RESUMO

BACKGROUND: Molecular and genetic studies of blood-stage Plasmodium falciparum parasites require limiting dilution cloning and prolonged cultivation in microplates. The entire process is laborious and subject to errors due to inaccurate dilutions at the onset and failed detection of parasite growth in individual microplate wells. METHODS: To precisely control the number of parasites dispensed into each microplate well, parasitaemia and total cell counts were determined by flow cytometry using parasite cultures stained with ethidium bromide or SYBR Green I. Microplates were seeded with 0.2 or 0.3 infected cells/well and cultivated with fresh erythrocytes. The c-SNARF fluorescent pH indicator was then used to reliably detect parasite growth. RESULTS: Flow cytometry required less time than the traditional approach of estimating parasitaemia and cell numbers by microscopic examination. The resulting dilutions matched predictions from Poisson distribution calculations and yielded clonal lines. Addition of c-SNARF to media permitted rapid detection of parasite growth in microplate wells with high confidence. CONCLUSION: The combined use of flow cytometry for precise dilution and the c-SNARF method for detection of growth improves limiting dilution cloning of P. falciparum. This simple approach saves time, is scalable, and maximizes identification of desired parasite clones. It will facilitate DNA transfection studies and isolation of parasite clones from ex vivo blood samples.


Assuntos
Benzopiranos/química , Clonagem Molecular/métodos , Citometria de Fluxo , Naftóis/química , Plasmodium falciparum/isolamento & purificação , Rodaminas/química , Malária Falciparum/diagnóstico
12.
J Basic Microbiol ; 61(3): 203-211, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33576034

RESUMO

Melanins are a diverse group of dark pigments with similar properties. In fungi, the most studied is the dihydroxynaphtalene (DHN)-melanin, present in several species including all the chromoblastomycosis agents, a chronic, disabling, and recalcitrant subcutaneous mycosis. It is synthesized in a pathway known as the pentaketide pathway, which has the agrochemical tricyclazole as an inhibitor, widely used in in vitro studies because it does not prevent the growth of fungi. There are different methodologies for qualitative and quantitative analyses of DHN-melanin, which made it possible to discover its important structural and antioxidant functions, with melanin acting as a protective factor against the host's immune system. Also, it can interact with some of the main antifungals of medical interest, reducing its activity and the susceptibility of fungi to these agents. This review aims to discuss the aspects of DHN-melanin, focusing on chromoblastomycosis, bringing the main findings of the published scientific studies, and highlighting the need for further research to understand this important fungal pathogenicity and a virulence factor.


Assuntos
Antifúngicos/farmacologia , Antioxidantes/farmacologia , Ascomicetos/efeitos dos fármacos , Cromoblastomicose/tratamento farmacológico , Melaninas/farmacologia , Naftóis/farmacologia , Ascomicetos/patogenicidade , Humanos , Melaninas/análise , Naftóis/análise
13.
Environ Technol ; 42(24): 3832-3839, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32167852

RESUMO

Traditional methodologies of conventional drinking water treatment are unable to remove some chemical compounds, such as those that cause odor and taste in drinking water. The present work aims to evaluate the efficiency of advanced oxidations processes, using UV radiation, O3 and O3 + UV in the degradation of geosmin (GSM) and 2-methylisoborneol (2-MIB) in synthetic samples. The efficiency of the processes was monitored by Gas Chromatography coupled with Mass Spectrometry using solid phase microextration technique. Experiments were carried out for 45 min with samplings every 15 min. The degradation results showed that UV radiation alone was not efficient for the degradation of both compounds. The fasted decay was observed by the combined use of O3 and UV with an ozone concentration of 15.84 mg L-1. Under these conditions, the final concentration of GSM was below the limit of quantification, so that approximately 99% of the initial concentration was degraded, while 2-MIB was degraded by 95%. With the same O3 concentration without the use of UV radiation, 63% and 65.7% of MIB and GSM, respectively, were removed. Higher efficiency of the treatment was observed with a higher O3 concentration which allows a shorter reaction time.


Assuntos
Poluentes Químicos da Água , Purificação da Água , Canfanos , Água Doce , Cromatografia Gasosa-Espectrometria de Massas , Naftóis/análise , Odorantes/análise , Poluentes Químicos da Água/análise
14.
Clin Transl Oncol ; 23(4): 892-901, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32974862

RESUMO

PURPOSE: P21-activated kinase 1 (PAK1), a serine/threonine protein kinase which functions downstream of RAC and CDC42 GTPase, is activated by a variety of stimuli, including RAS and other growth signaling factors. The extracellular signal kinase (ERK) and protein kinase B (AKT) signal pathways have been implicated in the pathogenesis of cancers. Whether PAK1 is sensitive to KRAS mutation signals and plays a role through ERK and AKT signaling pathways in NSCLC needs to be studied. METHODS: The expression of PAK1, ERK and AKT was detected in both lung cancer cell lines and clinical samples. PAK1 RNA interference and specific inhibitor of PAK1(IPA-3) were applied to lung cancer cell lines and mouse xenograft tumors. Cell growth was measured by MTT and colony formation assays. Cell migration and invasion were detected by wound healing and transwell assays. RAS mutation was detected by Taqman probe method. Correlation between KRAS, PAK1, ERK and AKT activities was analyzed in lung cancer patients. RESULTS: PAK1 was highly expressed not only in RAS mutant but also in RAS wild-type lung cancer cells. Using specific inhibitor of PAK1, IPA-3 and PAK1 RNA interference, cell proliferation, migration and invasion of lung cancer cells were reduced significantly, accompanied by decreased activities of ERK and AKT. Dual inhibition of ERK and AKT suppressed these cellular processes to levels comparable to those achieved by reduction in PAK1 expression. In NSCLC patients, PAK1 was not correlated with KRAS mutation but was significantly positively correlated with pERK and pAKT. CONCLUSION: PAK1 played roles in NSCLC proliferation and invasion via ERK and AKT signaling and suggested a therapeutic target for NSCLC.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/metabolismo , Neoplasias Pulmonares/metabolismo , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-akt/antagonistas & inibidores , Quinases Ativadas por p21/antagonistas & inibidores , Animais , Apoptose , Carcinoma Pulmonar de Células não Pequenas/enzimologia , Carcinoma Pulmonar de Células não Pequenas/patologia , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células/efeitos dos fármacos , Proliferação de Células/genética , Dissulfetos/farmacologia , Ativação Enzimática , Feminino , Genes ras/genética , Xenoenxertos , Humanos , Neoplasias Pulmonares/enzimologia , Neoplasias Pulmonares/patologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Mutação , Naftóis/farmacologia , Invasividade Neoplásica , Proteínas Proto-Oncogênicas c-akt/metabolismo , Ensaio Tumoral de Célula-Tronco , Cicatrização
15.
Cell Microbiol ; 23(3): e13283, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33108050

RESUMO

Toxoplasma gondii shows high dissemination and migration properties across biological barriers infecting immunologically privileged organs. Toxoplasma uses different routes for dissemination; however, the mechanisms are not fully understood. Herein, we studied the effects of proteases present in excretion/secretion products (ESPs) of Toxoplasma on MDCK cell monolayers. Ultrastructural analysis showed that ESPs of Toxoplasma disrupt the intercellular junctions (IJ) of adjacent cells. The tight junction (TJ) proteins ZO-1, occludin, and claudin-1 suffered a progressive decrease in protein levels upon ESPs treatment. In addition, ESPs induced mislocalization of such TJ proteins, along with the adherent junction protein E-cadherin, and this was prevented by pre-treating the ESPs with protease inhibitors. Reorganisation of cytoskeleton proteins was also observed. Endocytosis inhibitors, Dyngo®-4a and Dynasore, impeded the modifications, suggesting that TJ proteins internalisation is triggered by the ESPs proteases hence contributing to the loss of IJ. The observed disruption in TJ proteins went in line with a decrease in the transepithelial electrical resistance of the monolayers, which was significantly blocked by pre-treating ESPs with metalloprotease and serine protease inhibitors. Moreover, exposure of cell monolayers to ESPs facilitated paracellular migration of tachyzoites. Our results demonstrate that Toxoplasma ESPs contain proteases that can disrupt the IJ of epithelial monolayers and this could facilitate the paracellular route for Toxoplasma tissue dissemination and migration.


Assuntos
Junções Intercelulares/metabolismo , Peptídeo Hidrolases/metabolismo , Proteínas de Protozoários/metabolismo , Proteínas de Junções Íntimas/metabolismo , Toxoplasma/fisiologia , Animais , Caderinas/metabolismo , Claudina-1/metabolismo , Proteínas do Citoesqueleto/metabolismo , Cães , Células Epiteliais/metabolismo , Células Epiteliais/parasitologia , Hidrazonas/farmacologia , Junções Intercelulares/ultraestrutura , Células Madin Darby de Rim Canino , Metaloproteases/metabolismo , Movimento , Naftóis/farmacologia , Ocludina/metabolismo , Toxoplasma/enzimologia , Toxoplasma/patogenicidade , Proteína da Zônula de Oclusão-1/metabolismo
16.
An Acad Bras Cienc ; 92(3): e20190453, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33206799

RESUMO

Taste and odor compounds affect drinking water safety perception and may drive consumers to less secure water sources. Adsorption, using powered activated carbon, is the most common method to remove these compounds but greatly increases the amount of sludge generated. Another way of removing taste and odor compounds is to use filters with granular activated carbon (GAC) but little is still known on how to design them. In this work, the homogeneous surface diffusion model (HSDM) was used to model bench-scale kinetic and isotherm experiments and to simulate the removal of geosmin in a full-scale GAC filter. Geosmin adsorption isotherm was best described by the Freundlich model in all used carbons and film resistance (Kf) was more relevant to adsorption kinetics than pore diffusion (Ds). The simulation showed that in a filter with an empty bed contact time of 5 minutes and raw water with geosmin concentrations of 50, 75, and 100 ng.L-1, the effluent would exceed the trash-hold concentration (10 ng.L-1) in 98, 77, and 66 days, respectively, without considering biological removal.


Assuntos
Poluentes Químicos da Água , Purificação da Água , Adsorção , Carvão Vegetal , Naftóis
17.
Food Chem ; 328: 127101, 2020 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-32480258

RESUMO

Sudan I is a synthetic-azo dye commonly used to adulterate foods to increase sensory appearance. However, it is banned due to its carcinogenic, mutagenic and genotoxic properties, which represent a serious risk to human health. Thus, this paper proposes a feasibility study to identify and quantify Sudan I dye in ketchup samples using colour histograms (obtained from digital images) and multivariate analysis. The successive projections algorithm coupled with linear discriminant analysis (SPA-LDA) classified correctly all samples, while the partial least squares coupled with SPA for interval selection (iSPA-PLS) quantified adequately the adulterant, attaining values of RMSEP of 11.64 mg kg-1, R2 of 0.96, RPD of 5.28, REP of 13.63% and LOD of 39.45 mg kg-1. Therefore, the proposed methodology provides a simple, fast, inexpensive, promising analytical tool for the screening of both the quality and safety of ketchup samples. As a consequence, it can help to protect the consumer's health.


Assuntos
Análise de Alimentos/métodos , Contaminação de Alimentos/análise , Processamento de Imagem Assistida por Computador/métodos , Naftóis/análise , Algoritmos , Cor , Análise Discriminante , Análise de Alimentos/estatística & dados numéricos , Contaminação de Alimentos/estatística & dados numéricos , Qualidade dos Alimentos , Análise dos Mínimos Quadrados , Limite de Detecção , Análise Multivariada
18.
PLoS One ; 15(4): e0232476, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32353073

RESUMO

P5 ATPases are eukaryotic pumps important for cellular metal ion, lipid and protein homeostasis; however, their transported substrate, if any, remains to be identified. Ca2+ was proposed to act as a ligand of P5 ATPases because it decreases the level of phosphoenzyme of the Spf1p P5A ATPase from Saccharomyces cerevisiae. Repeating previous purification protocols, we obtained a purified preparation of Spf1p that was close to homogeneity and exhibited ATP hydrolytic activity that was stimulated by the addition of CaCl2. Strikingly, a preparation of a catalytically dead mutant Spf1p (D487N) also exhibited Ca2+-dependent ATP hydrolytic activity. These results indicated that the Spf1p preparation contained a co-purifying protein capable of hydrolyzing ATP at a high rate. The activity was likely due to a phosphatase, since the protein i) was highly active when pNPP was used as substrate, ii) required Ca2+ or Zn2+ for activity, and iii) was strongly inhibited by molybdate, beryllium and other phosphatase substrates. Mass spectrometry identified the phosphatase Pho8p as a contaminant of the Spf1p preparation. Modification of the purification procedure led to a contaminant-free Spf1p preparation that was neither stimulated by Ca2+ nor inhibited by EGTA or molybdate. The phosphoenzyme levels of a contaminant-free Spf1p preparation were not affected by Ca2+. These results indicate that the reported effects of Ca2+ on Spf1p do not reflect the intrinsic properties of Spf1p but are mediated by the activity of the accompanying phosphatase.


Assuntos
Transportadores de Cassetes de Ligação de ATP/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Transportadores de Cassetes de Ligação de ATP/genética , Transportadores de Cassetes de Ligação de ATP/isolamento & purificação , Trifosfato de Adenosina/metabolismo , Biocatálise , Cloreto de Cálcio/metabolismo , Ensaios Enzimáticos , Hidrólise , Mutação , Naftóis , Nitrofenóis/metabolismo , Compostos Organofosforados/metabolismo , Fosforilação , Proteínas Recombinantes/genética , Proteínas Recombinantes/isolamento & purificação , Proteínas Recombinantes/metabolismo , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/isolamento & purificação , Triazinas
19.
Org Biomol Chem ; 18(26): 4916-4921, 2020 07 08.
Artigo em Inglês | MEDLINE | ID: mdl-32353091

RESUMO

Herein, we report an eco-friendly, electrosynthetic approach for the intramolecular oxyselenylation of allyl-naphthol/phenol derivatives. This reaction proceeds with 0.2 equiv. of nBu4NClO4 as an electrolyte and Pt working electrodes in an undivided cell, resulting in the selenyl-dihydrofurans in good to excellent yields. Furthermore, several of the synthesized products presented a high percentage of acetylcholinesterase (AChE) inhibition, highlighting their potential anti-Alzheimer activity.


Assuntos
Inibidores da Colinesterase/farmacologia , Técnicas Eletroquímicas , Furanos/farmacologia , Naftóis/farmacologia , Compostos Organosselênicos/farmacologia , Fenóis/farmacologia , Acetilcolinesterase/metabolismo , Inibidores da Colinesterase/síntese química , Inibidores da Colinesterase/química , Relação Dose-Resposta a Droga , Eletrodos , Furanos/síntese química , Furanos/química , Humanos , Estrutura Molecular , Naftóis/química , Compostos Organosselênicos/síntese química , Compostos Organosselênicos/química , Fenóis/química
20.
Curr Top Med Chem ; 20(2): 121-131, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31820692

RESUMO

BACKGROUND: Antibacterial resistance is a serious public health problem infecting millions in the global population. Currently, there are few antimicrobials on the market against resistant bacterial infections. Therefore, there is an urgent need for new therapeutic options against these strains. OBJECTIVE: In this study, we synthesized and evaluated ten Bis(2-hydroxynaphthalene-1,4-dione) against Gram-positive strains, including a hospital Methicillin-resistant (MRSA), and Gram-negative strains. METHODS: The compounds were prepared by condensation of aldehydes and lawsone in the presence of different L-aminoacids as catalysts in very good yields. The compounds were submitted to antibacterial analysis through disk diffusion and Minimal Inhibitory Concentration (MIC) assays. RESULTS: L-aminoacids have been shown to be efficient catalysts in the preparation of Bis(2- hydroxynaphthalene-1,4-dione) from 2-hydroxy-1,4-naphthoquinones and arylaldehydes in excellent yields of up to 96%. The evaluation of the antibacterial profile against Gram-positive strains (Enterococcus faecalis ATCC 29212, Staphylococcus aureus ATCC 25923, S. epidermidis ATCC 12228) also including a hospital Methicillin-resistant S. aureus (MRSA) and Gram-negative strains (Escherichia coli ATCC 25922, Pseudomonas aeruginosa ATCC 27853 and Klebsiella pneumoniae ATCC 4352), revealed that seven compounds showed antibacterial activity within the Clinical and Laboratory Standards Institute (CLSI) levels mainly against P. aeruginosa ATCC 27853 (MIC 8-128 µg/mL) and MRSA (MIC 32-128 µg/mL). In addition, the in vitro toxicity showed all derivatives with no hemolytic effects on healthy human erythrocytes. Furthermore, the derivatives showed satisfactory theoretical absorption, distribution, metabolism, excretion, toxicity (ADMET) parameters, and a similar profile to antibiotics currently in use. Finally, the in silico evaluation pointed to a structure-activity relationship related to lipophilicity for these compounds. This feature may help them in acting against Gram-negative strains, which present a rich lipid cell wall selective for several antibiotics. CONCLUSION: Our data showed the potential of this series for exploring new and more effective antibacterial activities in vivo against other resistant bacteria.


Assuntos
Antibacterianos/síntese química , Antibacterianos/farmacologia , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Naftóis/síntese química , Naftóis/farmacologia , Antibacterianos/química , Relação Dose-Resposta a Droga , Humanos , Testes de Sensibilidade Microbiana , Estrutura Molecular , Naftóis/química , Relação Estrutura-Atividade
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