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2.
Braz J Med Biol Res ; 54(4): e10138, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33624728

RESUMO

Sarcoplasmic reticulum Ca2+-ATPase (SERCA2a) and sarcolemmal Na+/Ca2+ exchanger (NCX1) structures are involved in heart cell Ca2+ homeostasis. Previous studies have shown discrepancies in their function and expression in heart failure. The goal of this study was to evaluate heart function and hypertrophied muscle Ca2+-handling protein behavior under pressure overload. Twenty male Wistar rats were divided into two groups: Aortic stenosis (AoS), induced by a clip placed at the beginning of the aorta, and Control (Sham). After 18 weeks, heart function and structure were evaluated by echocardiogram. Myocardial function was analyzed by isolated papillary muscle (IPM) at basal condition and Ca2+ protein functions were evaluated after post-pause contraction and blockage with cyclopiazonic acid in IPM. Ca2+-handling protein expression was studied by western blot (WB). Echocardiogram showed that AoS caused concentric hypertrophy with enhanced ejection fraction and diastolic dysfunction inferred by dilated left atrium and increased relative wall thickness. IPM study showed developed tension was the same in both groups. AoS showed increased stiffness revealed by enhanced resting tension, and changes in Ca2+ homeostasis shown by calcium elevation and SERCA2a blockage maneuvers. WB revealed decreased NCX1, SERCA2a, and phosphorylated phospholambam (PLB) on serine-16 in AoS. AoS had left ventricular hypertrophy and diastolic dysfunction compared to Sham; this could be related to our findings regarding calcium homeostasis behavior: deficit in NCX1, SERCA2a, and phosphorylated PLB on serine-16.


Assuntos
Cálcio , Remodelação Ventricular , Animais , Cálcio/metabolismo , Homeostase , Masculino , Ratos , Ratos Wistar , ATPases Transportadoras de Cálcio do Retículo Sarcoplasmático/metabolismo
3.
Talanta ; 216: 120956, 2020 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-32456935

RESUMO

Solvents with both low density and viscosity have the advantage of higher extraction efficiency due to lower diffusivity and consequently higher mass transfer. In this study, a mixture design was performed for the synthesis of three different natural deep eutectic solvents (NADES) using citric acid, malic acid, and xylitol. The optimized proportion for each of the three solvents synthesized was selected based on density and viscosity values. The NADES were characterized by infrared spectroscopy analysis, that showed characteristic bands of the initial reagents and the presence of hydrogen bonds confirming the formation of each deep eutectic solvent. Then, the NADES were used as solvents in ultrasound-assisted extraction (UAE) and microwave-assisted extraction (MAE) of biological tissue and plant material samples for the determination of As, Cd, Hg, Pb, Se, and V by inductively coupled plasma mass spectrometry (ICP-MS). The results for the proposed methods were compared to microwave-assisted acid digestion (MW-AD). The extraction recoveries ranged from 80 to 120% for most of the elements determined. The use of NADES as carbon sources improved the sensitivity of the As and Cd analyses, due to charge transfer reactions between the analyte and C+ and/or other carbon species. In addition, the Analytical Eco-Scale was used to assess the greenness of the proposed analytical procedures (UAE and MAE). It showed that the UAE and MAE methods provided excellent green analyses, while the MW-AD method was rated as an acceptable green procedure.


Assuntos
Ácido Cítrico/química , Malatos/química , Metais Pesados/isolamento & purificação , Plantas/química , Xilitol/química , Animais , Ácido Cítrico/síntese química , Concentração de Íons de Hidrogênio , Malatos/síntese química , Espectrometria de Massas , Metais Pesados/química , Micro-Ondas , Solventes/síntese química , Solventes/química , Ondas Ultrassônicas , Viscosidade , Xilitol/síntese química
4.
Carbohydr Polym ; 226: 115205, 2019 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-31582062

RESUMO

This study aimed to investigate a standardized biopolymer, cashew gum (CG), in human oesophageal mucosa and mice with experimentally-induced non-erosive reflux disease (NERD). Human oesophageal biopsies from NERD patients were collected to evaluate the mucosal protection of CG through transepithelial electrical resistance (TER), mucosal permeability, and mucoadhesiveness tests. A surgical model of NERD in mice was induced, and barrier functions followed by suggestive oesophageal inflammatory hallmarks were evaluated. Pre-coating of CG was effective in human oesophageal mucosa by attenuating drop of TER and mucosal permeability. Labelled-CG adheres to human oesophageal mucosa for up to 1 h. In animal studies, CG improved parameters of barrier function (TER and mucosal permeability) in distal oesophagus mucosa. CG also promoted sequential support by reducing inflammatory hallmarks of oesophageal damage. CG confers topical oesophageal mucosal protection due to its mucoadhesiveness and anti-inflammatory profile. Long-duration mucoprotective products can be further explored as first-line/adjuvant NERD therapy.


Assuntos
Anacardium/metabolismo , Biopolímeros/farmacologia , Biopolímeros/farmacocinética , Mucosa Esofágica , Refluxo Gastroesofágico/tratamento farmacológico , Adulto , Idoso , Animais , Impedância Elétrica , Mucosa Esofágica/efeitos dos fármacos , Mucosa Esofágica/metabolismo , Feminino , Humanos , Camundongos , Pessoa de Meia-Idade , Permeabilidade/efeitos dos fármacos , Substâncias Protetoras/farmacologia , Adulto Jovem
5.
Talanta ; 199: 361-369, 2019 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-30952271

RESUMO

Natural deep eutectic solvents (NADES) based on xylitol, citric acid, and malic acid were synthesized and were then characterized using infrared spectroscopy, thermogravimetry (TG), differential scanning calorimetry (DSC), also density and viscosity were measurements. The deep eutectic solvents were used as solvent in ultrasound-assisted extraction (DES-UAE) of plant samples prior to elemental analysis. Inductively coupled plasma-mass spectrometry (ICP-MS) and inductively coupled plasma-optical emission spectrometry (ICP OES) were employed for the determination of As, Ca, Cd, Cu, Fe, K, Mg, Mn, Na, P, and Zn in the extracts. The infrared analyses of the NADES revealed bands characteristic of the initial reagents, with the presence of hydrogen bonds, which confirmed the formation of a NADES. The thermal analyses showed decomposition temperatures of around 170 °C and endothermic events related to degradation of the NADES. The viscosity and density parameters were found to be related to the presence of hydrogen bonds. The extraction recoveries ranged from 80% to 120%, with some analytes presenting poor recoveries. There were no significant differences between the NADES, in terms of the concentrations of the analytes found in the extracts. However, there were differences between the analyte concentrations obtained using the NADES extraction method and the concentrations obtained using microwave-assisted acid digestion (MW-AD), possibly due to the different types of interactions between the solvents and the analytes. Plant tissues are complex matrices containing substantial amounts of silica, so some elements may be tightly bound and consequently difficult to release. The results indicated that UAE using NADES is a promising technique for the elemental extraction of plant samples.


Assuntos
Métodos Analíticos de Preparação de Amostras , Ácido Cítrico/química , Malatos/química , Metais/análise , Extratos Vegetais/análise , Solventes/química , Xilitol/química , Ácido Cítrico/síntese química , Malatos/síntese química , Espectrometria de Massas , Solventes/síntese química , Xilitol/síntese química
6.
Laryngoscope ; 128(5): 1157-1162, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29076531

RESUMO

OBJECTIVES/HYPOTHESIS: Evaluate the effect of in vitro exposure of mice laryngeal mucosa to solutions that simulated human gastric juice and to assess the topical protective effect of cashew gum on mice laryngeal mucosal integrity in vitro. STUDY DESIGN: Animal study. METHODS: Murine (Swiss) laryngeal samples were mounted in Ussing chambers. The luminal side of biopsies was exposed to solutions of different acidity with or without pepsin and/or taurodeoxycholic acid (TDC). Transepithelial electrical resistance (TER) was continuously recorded. The topical protective effect of cashew gum solution was evaluated by precoating the biopsies before the exposure with a solution at pH 5 containing 5 mM TDC. Changes in TER and mucosal permeability to fluorescein were measured. RESULTS: Exposure of laryngeal mucosa to acidic solutions containing pepsin and TDC provoked a pH-dependent drop in TER with the maximal effect at pH 1, but still present at pH 5 (weakly acidic). The exposure of the laryngeal mucosa to a solution of pH 5 with TDC, but not with pepsin, produced a dose-dependent decrease in TER. Precoating the mucosa with cashew gum prevented the reduction of TER and increased transepithelial permeability by exposure to a solution at pH5 containing TDC. CONCLUSIONS: Weakly acidic solutions containing bile acids can produce impairment of laryngeal epithelial barrier, which may be protected by topical treatment with cashew gum. LEVEL OF EVIDENCE: NA. Laryngoscope, 128:1157-1162, 2018.


Assuntos
Anacardium , Mucosa Laríngea/efeitos dos fármacos , Extratos Vegetais/farmacologia , Administração Tópica , Animais , Masculino , Camundongos , Pepsina A/farmacologia , Extratos Vegetais/administração & dosagem , Ácido Taurodesoxicólico/farmacologia
7.
Appl Microbiol Biotechnol ; 102(3): 1215-1228, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29247366

RESUMO

A strain of embryonic human kidney cells (HEK293) was transiently co-transfected with the expression vectors coding for the α- and ß-subunits of human thyroid-stimulating hormone (hTSH), and, for the first time, a human cell-derived recombinant hTSH was synthesized and extensively characterized. The purification strategy involving two steps provided an overall yield of 55% and a purity level > 90%. The purified material (hTSH-HEK) was analyzed and compared to a CHO-derived recombinant preparation (hTSH-CHO) and to a pituitary-derived (hTSH-Pit) preparation. The three preparations showed an equivalent purity (> 95%) with a hTSH-HEK molecular mass 2.1% lower than that of hTSH-CHO and 2.7% higher than that of hTSH-Pit. Remarkable differences were found in the carbohydrate moiety, the lowest sialic acid content and highest fucose content being observed in hTSH-HEK. In vivo biological activity was confirmed for the three preparations, the hTSH-HEK bioactivity being 39 and 16% lower than those of hTSH-CHO and hTSH-Pit, respectively. The hTSH-HEK circulatory half-life (t 1/2) was also shorter than those of hTSH-CHO (1.5-fold) and hTSH-Pit (1.2-fold). According to these findings, HEK-293-derived hTSH can be considered to be useful for clinical applications, in view as well of its human origin and particular carbohydrate composition.


Assuntos
Carboidratos/análise , Células Epiteliais/metabolismo , Glicoproteínas/biossíntese , Tireotropina/biossíntese , Animais , Células CHO , Cricetinae , Cricetulus , Fucose/análise , Glicosilação , Células HEK293 , Meia-Vida , Humanos , Ácido N-Acetilneuramínico/análise , Proteínas Recombinantes/biossíntese , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Transfecção
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