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1.
Plants (Basel) ; 13(11)2024 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-38891254

RESUMO

This study aimed to evaluate the spasmolytic activity of an underground parts extract of Gentiana asclepiadea L. (Gentianaceae), assess its antioxidant and antimicrobial activities, and explore the impact of extract encapsulation on the aforementioned bioactivities. An extract encapsulated by spray drying with whey protein, pure extract, and pure whey protein were comparatively tested. The main compounds identified via HPLC-DAD analysis underwent in silico ADME assessment. The spasmolytic effect was tested on a model of spontaneous rat ileum contractions, and the mechanism of action was further evaluated on acetylcholine-, KCl-, CaCl2-, BaCl2-, histamine-, N(ω)-nitro-L-arginine methyl ester-, and glibenclamide-modified contractions. The most abundant compounds were secoiridoids (dominantly gentiopicroside), followed by C-glycosylated flavonoids and xanthones. Both pure and encapsulated extracts achieved significant spasmolytic effects, despite the spasmogenic activity of pure whey protein. The extract may exert its spasmolytic effect through multiple pathways, predominantly by antagonizing the Ca2+ channel and opening the K+ channel, while the nitric oxide pathway appears not to be involved. The antimicrobial and antioxidant activities of the pure extract were moderate. The extract stabilized by encapsulation retained all of the tested bioactivities of the unencapsulated extract. The obtained results suggest that G. asclepiadea has potential for use in the treatment of some gastrointestinal complaints and that the encapsulated extract could be a valuable functional ingredient in pharmaceutical and food products.

2.
Plants (Basel) ; 13(3)2024 Feb 04.
Artigo em Inglês | MEDLINE | ID: mdl-38337986

RESUMO

The roots of Gentiana lutea L. are utilized in the preparation of various beverages and herbal remedies, serving as a traditional remedy for gastrointestinal ailments. The spasmolytic activity that could substantiate the traditional use of G. lutea root had not been investigated. The main objective goal of the study was to determine the validity of its use as a traditional remedy. The extraction of G. lutea root was performed using a 50% hydroethanolic solvent with three different extraction techniques: ultrasound-assisted extraction (UAE), heat-assisted extraction, and percolation. The spasmolytic activity was tested on isolated rat ileum. The mechanism of action was monitored using the models of spontaneous contractions and acetylcholine-, histamine-, CaCl2-, Bay K8644-, L-NAME-, ODQ-, apamin-, BaCl2-, charybdotoxin-, glibenclamide-, TRAM-34-, and quinine-modified contractions. UAE, having the best bioactivity, was further subjected to a liquid-liquid extraction fractionation. HPLC phytochemical analysis was performed for all tested extracts and fractions. Gentian root extracts were rich in secoiridoids, xanthones, and flavonoids. The UAE has shown better results on spontaneous contractions in comparison to its fractions, leading to the more detailed testing of its spasmolytic mechanism of activity. The extract's activity is primarily mediated through intermediate conductance Ca2+-activated K+ channels, ATP-sensitive K+ channels, voltage-sensitive K+ channels, and mechanisms that activate Ca2+ channels. Overall, the G. lutea root shows great potential in the treatment of spasmodic gastrointestinal ailments.

3.
Account Res ; : 1-29, 2023 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-38108298

RESUMO

The "publish or perish" approach has become an integral part of an academic's life when seeking positions, striving for promotions, or competing for funding. This approach often hinges on journal-based metrics which push researchers to seek publication in journals indexed in the Web of Science. Due to the pressure to publish a certain number of publications in journals indexed in the Web of Science, researchers might attempt to find a journal with a lower impact factor, i.e., less popular and visible journals in the scientific community. Even more concerning is the fact that researchers might publish their results in predatory journals. This paper analyzes the consequence of introducing a journal indicators-based academic evaluation by analyzing productivity and publication patterns of researchers. Moreover, this paper investigates the correlation between journal-based academic evaluation rules and researchers' ethics. The analysis is based on bibliometric data collected from the Web of Science database. The case study subject is the Serbian research landscape before and after the introduction of a journal metrics-based academic evaluation.

4.
Pharmaceutics ; 15(5)2023 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-37242618

RESUMO

The use of medicinal plant species and their products is widespread in the field of gastrointestinal and respiratory diseases. This study aimed to evaluate the traditional use of Salvia sclarea L., clary sage, finding the possible mechanisms of its spasmolytic and bronchodilator actions in in vitro conditions supported by molecular docking analysis, along with the antimicrobial effects. Four dry extracts were prepared from the aerial parts of S. sclarea, using absolute or 80% (v/v) methanol by the method of a single-stage maceration or an ultrasound-assisted extraction. Characterization of the bioactive compounds by high-performance liquid chromatography indicated the presence of significant amounts of polyphenolics, with rosmarinic acid as the prevalent one. The spontaneous ileal contractions were best inhibited by the extract prepared with 80% methanol and maceration. The same extract was superior in the carbachol- and KCl-induced tracheal smooth muscle contractions, being the strongest bronchodilator agent. The most powerful relaxation of KCl-induced ileal contractions was achieved with the extract made of absolute methanol by maceration, while the 80% methanolic extract made with the ultrasound method generated the best spasmolytic effects in the acetylcholine-induced ileal contractions. Docking analysis suggested that apigenin-7-O-glucoside and luteolin-7-O-glucoside exhibited the highest binding affinity to voltage-gated calcium channels. Gram (+) bacteria were more susceptible to the effects of the extracts, particularly Staphylococcus aureus, in contrast to Gram (-) bacteria and Candida albicans. This is the first study to point out the influence of S. sclarea methanolic extracts on the gastrointestinal and respiratory spasm reduction, paving the way for their potential place in complementary medicine.

5.
Artigo em Inglês | MEDLINE | ID: mdl-36767915

RESUMO

There is no definitive consensus about the cost-effectiveness of minimally invasive aortic valve replacement (AVR) (MI-AVR) compared to conventional AVR (C-AVR). The aim of this study was to compare the rate of postoperative complications and total hospital costs of MI-AVR versus C-AVR overall and by the type of aortic prosthesis (biological or mechanical). Our single-center retrospective study included 324 patients over 18 years old who underwent elective isolated primary AVR with standard stented AV prosthesis at the Institute for Cardiovascular Diseases "Dedinje" between January 2019 and December 2019. Reintervention, emergencies, combined surgical interventions, and patients with sutureless valves were excluded. In both MI-AVR and C-AVR, mechanical valve implantation contributed to overall reduction of hospital costs with equal efficacy. The cost-effectiveness ratio indicated that C-AVR is cheaper and yielded a better clinical outcome with mechanical valve implantation (67.17 vs. 69.5). In biological valve implantation, MI-AVR was superior. MI-AVR patients had statistically significantly higher LVEF and a lower Euro SCORE than C-AVR patients (Mann-Whitney U-test, p = 0.002 and p = 0.002, respectively). There is a slight advantage to MI-AVR vs. C-AVR, since it costs EUR 9.44 more to address complications that may arise. Complications (mortality, early reoperation, cerebrovascular insult, pacemaker implantation, atrial fibrillation, AV block, systemic inflammatory response syndrome, wound infection) were less frequent in the MI-AVR, making MI-AVR more economically justified than C-AVR (18% vs. 22.1%).


Assuntos
Estenose da Valva Aórtica , Implante de Prótese de Valva Cardíaca , Humanos , Adolescente , Valva Aórtica/cirurgia , Estenose da Valva Aórtica/cirurgia , Estudos Retrospectivos , Resultado do Tratamento , Fatores de Risco , Desenho de Prótese
6.
Food Chem ; 405(Pt A): 134816, 2023 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-36345100

RESUMO

Innovative eco-friendly methods based on natural deep eutectic solvents (NaDES) coupled with ultrasound-assisted extraction were employed for chokeberry anthocyanins extractions. Nine different NaDES composed of choline chloride as a hydrogen bond acceptor and organic acids (lactic, citric, malic), sugars (glucose, fructose), polyols (glycerol, 1,2-propanediol, sorbitol), and an amide (urea) as hydrogen bond donors were screened. Malic acid-containing NaDES was selected for optimization extraction conditions (time, temperature, water in NaDES) by response surface methodology. Optimal conditions for simultaneously maximizing the anthocyanins extraction (cyanidin-3-O-glucoside, cyanidin-3-O-galactoside, cyanidin-3-O-arabinoside, total anthocyanins) were 42.7 °C, 90 min, and 40 % (w/w) water in NaDES. In the next stage of this study, the possibility to improve anthocyanins extraction at elevated temperatures by incorporating different concentrations of hydroxypropyl-ß-cyclodextrin into selected NaDES was investigated. The extraction was improved at hydroxypropyl-ß-cyclodextrin concentrations up to 3 % (w/w). To clarify the interaction of NaDES components and anthocyanins, a molecular dynamic simulation was conducted.


Assuntos
Antocianinas , Ciclodextrinas , Antocianinas/química , Solventes Eutéticos Profundos , 2-Hidroxipropil-beta-Ciclodextrina , Extratos Vegetais/química , Água , Solventes/química
7.
Molecules ; 27(21)2022 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-36364433

RESUMO

The residue after sieving ("dust") from the willow gentian underground parts is an unexploited herbal tea by-product, although it contains valuable bioactive compounds. Cyclodextrins as efficient green co-solvents, cage molecules, and multifunctional excipients could improve the extraction and contribute to the added value of the resulting extracts. The objective of this study was to determine the optimal conditions for the extraction of gentiopicroside, isogentisin, and total phenolics (TPC) from willow gentian "dust" using ultrasound-assisted water extraction coupled with hydroxypropyl-ß-cyclodextrin (HPßCD). The influence of extraction temperature (X1: 20-80 °C), time (X2: 20-50 min), and HPßCD concentration (X3: 2-4% w/v) was analyzed employing the response surface methodology (RSM). The optimal extraction conditions for simultaneously maximizing the extraction yield of all monitored responses were X1: 74.89 °C, X2: 32.57 min, and X3: 3.01% w/v. The experimentally obtained response values under these conditions (46.96 mg/g DW for gentiopicroside, 0.51 mg/g DW for isogentisin, and 12.99 mg GAE/g DW for TPC) were in close agreement with those predicted, thus confirming the suitability and good predictive accuracy of the developed RSM models. Overall, the developed extraction system could be an applicable alternative strategy to improve the extraction of bioactive compounds from the underutilized "dust" of willow gentian underground parts.


Assuntos
Gentiana , Salix , Polifenóis/análise , 2-Hidroxipropil-beta-Ciclodextrina , Água , Poeira , Fenóis/química , Extratos Vegetais/química
8.
Plants (Basel) ; 11(20)2022 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-36297701

RESUMO

This study aimed to evaluate the potentials for skin-beneficial effects of the hydroethanolic extract of the aerial parts of ironwort (Sideritis raeseri Boiss. & Heldr. subsp. raeseri) and its fractions (petroleum ether, ethyl acetate, n-butanol and water). For these purposes, chemical analysis and in vitro antioxidant, anti-tyrosinase and antimicrobial assays, as well as determination of sun protection factor (SPF), were performed. The highest total phenolic content and quantity of individual flavonoids, chlorogenic acid and verbascoside were determined in the n-butanol fraction, which is in line with results obtained for antioxidant activity. The greatest antimicrobial activity against Staphylococcus aureus, Staphylococcus epidermidis and Pseudomonas aeruginosa, the most common causative agents of the skin infections in humans, was exhibited by the ethyl acetate fraction. The strongest anti-tyrosinase activity was shown by the hydroethanolic extract (52.64% of inhibition at 100 µg/mL). Almost all tested samples showed photoprotective activity with SPF higher than 6 obtained at a low concentration of 0.1 mg/mL, which was more than 15 for the butanol fraction. These findings revealed that the hydroethanolic extract of S. raeseri aerial parts could be a valuable ingredient in the formulation of cosmetic and medicinal products intended to overcome various skin disorders.

9.
Plants (Basel) ; 11(20)2022 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-36297704

RESUMO

Bilberry fruits (Vaccinium myrtillus L.) are one of the richest natural sources of anthocyanins and are widely used due to their pharmacological and nutritional properties. To ensure their maximum application potential, it is necessary to overcome the limitations of conventional extraction solvents and techniques. This study aimed to develop a green method for bilberry anthocyanin extraction using natural deep eutectic solvents (NaDES) integrated with ultrasound-assisted extraction (UAE) in order to define extraction conditions that will prevent decomposition of the anthocyanins or the loss of bioactivity. After a screening of ten different NaDES, choline chloride:sorbitol (1:1) was selected as the most effective. Furthermore, the influence analysis and optimization of the NaDES-UAE extraction conditions were carried out employing response surface methodology. The optimal conditions were found to be an extraction time of 37.63 min, a temperature of 48.38 °C, and 34.79% (w/w) water in NaDES. The extraction yields of target compounds under optimized extraction conditions were 0.27 mg/g DW of cyanidin-3-O-glucoside and 2.12 mg CGE/g DW of TAC. The obtained optimized extract showed promising radical scavenging and antimicrobial activity. A stability study with the optimized extract revealed that refrigerated storage at 4 °C in the dark provided the best anthocyanins preservation. Overall, the developed NaDES-UAE method showed promising application potential and can be considered as a high-efficiency green alternative to conventional anthocyanins extraction methods, enabling the preservation of active ingredients and the bioactivity of extracts.

10.
Asian Cardiovasc Thorac Ann ; 30(9): 977-984, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36066027

RESUMO

BACKGROUND: The revascularisation strategy for concomitant carotid and coronary disease is unknown. Simultaneous or stage coronary artery stenting and carotid endarterectomy are the most common revascularisation approach in the CABG population. This study aimed to evaluate long-term results after simultaneous carotid artery stenting or carotid endarterectomy in patients who underwent coronary artery bypass surgery. METHODS: This is a prospective cohort non-randomised single-institution study. During the period from 2012 to 2015, sixty consecutive patients (65.9 ± 7.41 mean) underwent simultaneous carotid artery stenting and coronary artery bypass surgery (n = 30) or simultaneous carotid endarterectomy and coronary artery bypass surgery (n = 30). The primary endpoints were short- and long-term rates of adverse events (transient ischemic attack, stroke, myocardial infarction, and death). The mean follow-up was 62.05 ± 11.12 months. RESULTS: In-hospital mortality was insignificantly higher in the carotid endarterectomy, and coronary artery bypass surgery group (6.6% vs. 0%), the rate of stroke and myocardial infarction was similar (13.3% and 0% in the carotid endarterectomy and coronary artery bypass surgery group vs. 6.6% and 3.3% in the carotid artery stenting and coronary artery bypass surgery group, respectively). The intensive care unit readmission was significantly higher in the surgical revascularisation approach; it was an independent predictor of hospital mortality. The overall mortality during the follow-up period was 14.28% in both groups. Freedom of the composite adverse outcomes (stroke, myocardial infarction, and death) was 78.55%. CONCLUSION: Comparing two revascularisation strategies is not straightforward due to different anatomical indications for carotid artery stenting and endarterectomy. We consider that each technique has an essential role in carotid revascularisation. Good selection of patients, according to indications, contributes to satisfactory short- and long-term results.


Assuntos
Estenose das Carótidas , Doença da Artéria Coronariana , Endarterectomia das Carótidas , Infarto do Miocárdio , Acidente Vascular Cerebral , Artérias Carótidas , Estenose das Carótidas/complicações , Estenose das Carótidas/diagnóstico por imagem , Estenose das Carótidas/cirurgia , Doença da Artéria Coronariana/complicações , Doença da Artéria Coronariana/diagnóstico por imagem , Doença da Artéria Coronariana/cirurgia , Endarterectomia das Carótidas/efeitos adversos , Humanos , Infarto do Miocárdio/complicações , Estudos Prospectivos , Estudos Retrospectivos , Stents , Resultado do Tratamento
11.
Tex Heart Inst J ; 49(1)2022 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-35099560

RESUMO

Open surgical aortic valve replacement (SAVR) is a viable alternative to transcatheter implantation in low-risk patients. In this light, we evaluated the safety and effectiveness of SAVR performed through conventional and less invasive surgical approaches in a high-volume center. We retrospectively reviewed the records of 395 consecutive patients who underwent open SAVR from January 2019 through December 2019 in our center. We evaluated and compared the operative results and postoperative major adverse outcomes of 3 surgical approaches: full median sternotomy (n=267), upper ministernotomy (ministernotomy) (n=106), and right anterior thoracotomy (minithoracotomy) (n=22). Overall, the 30-day all-cause mortality rate was 0.8% (3 patients). Stroke occurred in 8 patients (2%), disabling stroke in 4 patients (1%), myocardial infarction in 1 (0.2%), and surgical site infection in 13 (3.2%). There was no difference in 30-day mortality rate or incidence of postoperative major adverse events among the 3 surgical groups. Stroke and surgical site infection occurred more frequently, but not significantly so, in the full-sternotomy group. The mean hospital stay was longer after full sternotomy (9.1 ± 5.5 d) than after ministernotomy (7.5 ± 2.9 d) or minithoracotomy (7.4 ± 1.9 d) (P=0.012). Our findings suggest that open SAVR performed in a high-volume center is associated with a low early mortality rate and that less invasive approaches result in faster postoperative recovery and shorter hospital stays.


Assuntos
Estenose da Valva Aórtica , Implante de Prótese de Valva Cardíaca , Acidente Vascular Cerebral , Substituição da Valva Aórtica Transcateter , Valva Aórtica/cirurgia , Estenose da Valva Aórtica/diagnóstico , Estenose da Valva Aórtica/etiologia , Estenose da Valva Aórtica/cirurgia , Implante de Prótese de Valva Cardíaca/efeitos adversos , Implante de Prótese de Valva Cardíaca/métodos , Humanos , Estudos Retrospectivos , Fatores de Risco , Esternotomia/efeitos adversos , Esternotomia/métodos , Acidente Vascular Cerebral/epidemiologia , Acidente Vascular Cerebral/etiologia , Infecção da Ferida Cirúrgica/epidemiologia , Infecção da Ferida Cirúrgica/etiologia , Infecção da Ferida Cirúrgica/cirurgia , Substituição da Valva Aórtica Transcateter/efeitos adversos , Resultado do Tratamento
12.
Arch Pharm (Weinheim) ; 354(11): e2100238, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34374111

RESUMO

Several coumarin derivatives with a directly attached azole substituent at C-4 were synthesized and biologically studied for their anticancer properties. The cell lines used for this investigation (HeLa, K-562, MDA-MB-53, and MCF-7) demonstrated different sensitivities. The best response in the MTT (3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2H-tetrazolium bromide) assay was shown by K-562 cells, with compounds displaying activity (3c, IC50 3.06 µM; 4a, IC50 5.24 µM; 4c, IC50 4.7 µM) similar to that of cisplatin (IC50 ~6 µM), which was used as the standard. The studied azole-substituted coumarins demonstrated weaker activity toward other cell lines, except for compound 4c, which was equally potent in the case of MCF-7 cells. Additional biological evaluations supported interference with the cell cycle as a potential mechanism of action and confirmed the absence of toxicity in zebrafish embryos. On the basis of these initial results, 4-azole coumarins should be explored further. Although their activity would need additional optimization, the fact that these compounds are fragment-like structures with MW <300 and clog P <3 offers enough flexibility to fine-tune their drug-like properties.


Assuntos
Antineoplásicos/farmacologia , Cumarínicos/farmacologia , Neoplasias/tratamento farmacológico , Animais , Antineoplásicos/síntese química , Antineoplásicos/química , Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Cisplatino/farmacologia , Cumarínicos/síntese química , Cumarínicos/química , Feminino , Células HeLa , Humanos , Concentração Inibidora 50 , Células K562 , Células MCF-7 , Masculino , Neoplasias/patologia , Relação Estrutura-Atividade , Testes de Toxicidade , Peixe-Zebra
13.
Sci Rep ; 11(1): 3013, 2021 02 04.
Artigo em Inglês | MEDLINE | ID: mdl-33542344

RESUMO

Associative memory (AM) reflects the ability to remember and retrieve multiple pieces of information bound together thus enabling complex episodic experiences. Despite growing interest in the use of transcranial direct current stimulation (tDCS) for the modulation of AM, there are inconsistent evidence regarding its benefits. An alternative to standard constant tDCS could be the application of frequency-modulated tDCS protocols, that mimic natural function-relevant brain rhythms. Here, we show the effects of anodal tDCS oscillating in theta rhythm (5 Hz; 1.5 ± 0.1 mA) versus constant anodal tDCS and sham over left posterior parietal cortex on cued recall of face-word associations. In a crossover design, each participant completed AM assessment immediately following 20-min theta-oscillatory, constant, and sham tDCS, as well as 1 and 5 days after. Theta oscillatory tDCS increased initial AM performance in comparison to sham, and so did constant tDCS. On the group level, no differences between oscillatory and constant tDCS were observed, but individual-level analysis revealed that some participants responded to theta-oscillatory but not to constant tDCS, and vice versa, which could be attributed to their different physiological modes of action. This study shows the potential of oscillatory tDCS protocols for memory enhancement to produce strong and reliable memory-modulating effects which deserve to be investigated further.


Assuntos
Cognição/fisiologia , Lobo Parietal/fisiologia , Córtex Pré-Frontal/fisiologia , Ritmo Teta/fisiologia , Adulto , Cognição/efeitos da radiação , Feminino , Humanos , Masculino , Memória , Rememoração Mental/fisiologia , Rememoração Mental/efeitos da radiação , Lobo Parietal/diagnóstico por imagem , Lobo Parietal/efeitos da radiação , Córtex Pré-Frontal/efeitos da radiação , Ritmo Teta/efeitos da radiação , Estimulação Transcraniana por Corrente Contínua/métodos , Adulto Jovem
14.
Asian Cardiovasc Thorac Ann ; 29(9): 903-909, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33611947

RESUMO

BACKGROUND: Total arterial revascularization is the most durable and technically the most demanding type of coronary artery bypass grafting procedure. It has proven long-term supremacy in comparison to conventional coronary artery bypass grafting. In our study, we investigated the reliability of EuroSCORE II as a predictor of intrahospital death. We showed its impact on adverse perioperative events. METHODS: In this nonrandomized prospective study, we analyzed 116 consecutive patients who underwent the total arterial revascularization procedure at our Institute from January 2011 until the present. For myocardial revascularization, the most suitable combinations with left internal mammary artery, right internal mammary artery, and radial artery grafts were used. Main fact in this research was intrahospital mortality value in comparison with the value predicted. RESULTS: There were 104 (89.7%) males and 12 (10.3%) females. Mean preoperative EuroSCORE II prediction value was 1.98% and postoperative we obtained 1.72%. Postoperative redo for bleeding was 6%. Positive correlation was proven between the EuoroSCORE II value and intensive care unit stay (0.452; p < 0.001). Among patients who received two internal mammary arteries, the highest EuroSCORE II was among those with presternal wound infection (p = 0.005). Patients with bilateral internal mammary arteries and diabetes showed that they have the highest values of EuroSCORE II and, at the same time, that they are extremely prone to wound problems. CONCLUSIONS: We achieved a lower intrahospital mortality level than it was predicted with preoperative EuroSCORE II value. This tool is a reliable method for preoperative death risk calculation in this group of patients.


Assuntos
Artéria Torácica Interna , Ponte de Artéria Coronária , Feminino , Humanos , Masculino , Artéria Torácica Interna/cirurgia , Complicações Pós-Operatórias/etiologia , Estudos Prospectivos , Reprodutibilidade dos Testes , Estudos Retrospectivos , Resultado do Tratamento
15.
Molecules ; 25(6)2020 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-32192164

RESUMO

Establishing the metabolism pathway of the drug undergoing the hepatic biotransformation pathway is one of the most important aspects in the preclinical discovery process since the presence of toxic or reactive metabolites may result in drug withdrawal from the market. In this study, we present the structural elucidation of six, not described yet, metabolites of an antipsychotic molecule: molindone. The elucidation of metabolites was supported with a novel photocatalytical approach with the use of WO3 and WS2 assisted photochemical reactions. An UHPLC-ESI-Q-TOF combined system was used for the registration of all obtained metabolite profiles as well as to record the high resolution fragmentation spectra of the observed transformation products. As a reference in the in vitro metabolism simulation method, the incubation with human liver microsomes was used. Chemometric comparison of the obtained profiles pointed out the use of the WO3 approach as being more convenient in the field of drug metabolism studies. Moreover, the photocatalysis was used in the direction of the main drug metabolite synthesis in order to further isolation and characterization.


Assuntos
Luz , Desintoxicação Metabólica Fase I , Microssomos Hepáticos/metabolismo , Molindona/metabolismo , Espectrometria de Massas em Tandem/métodos , Biotransformação/efeitos da radiação , Catálise/efeitos da radiação , Cromatografia Líquida de Alta Pressão , Humanos , Cinética , Desintoxicação Metabólica Fase I/efeitos da radiação , Redes e Vias Metabólicas/efeitos da radiação , Metaboloma/efeitos da radiação , Microssomos Hepáticos/efeitos da radiação , Molindona/química , Análise Multivariada , Análise de Componente Principal
16.
Anal Bioanal Chem ; 411(22): 5755-5763, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31201462

RESUMO

A novel voltammetric method was developed for brimonidine (BRIM) determination in deproteinized aqueous humor, simplifying preparation of biological samples for analysis for stability studies. The differential pulse voltammetric (DPV) method using boron doped diamond electrode (BDDE), based on characteristic oxidation peaks, was proposed and successfully applied. The linearity range was within 5.0 × 10-6 to 5.0 × 10-5 M of brimonidine, and limit of detection and limit of quantitation were 1.94 × 10-6 M and 6.46 × 10-6 M, respectively. Intra-day and inter-day precision and accuracy were evaluated and all results were in accordance with validation ICH guidelines. The best short-term stability study results were obtained for a concentration level of 3.0 × 10-5 M expressed by deviation of + 1.86% between initial and post storage concentrations. A long-term stability study was performed for two concentrations of 3.0 × 10-5 M and 5.0 × 10-5 M and resulted in deviations of + 1.63% and + 3.56%, respectively. A freeze and thaw stability study indicated that samples might be frozen only once. The enhancement of DPV/BDDE method sensitivity gained by modification, for the analysis of immeasurable BRIM quantities in native, untreated aqueous humor, was reached for quantities of 6 or 12 nmol/0.1 mL aqueous humor with acceptable accuracy (up to + 7.5%). The nature of the process-the irreversible one electron oxidation voltammetric peak of BRIM-limited the sensitivity. Only electrochemical pre-treatment of the BDD electrode before each measurement significantly speeded up the whole procedure. The advantages of the proposed method are simplicity, short-time performance, and good specificity/selectivity, as well as satisfactory accuracy, and no chemical modification of BDDE was necessary.


Assuntos
Agonistas de Receptores Adrenérgicos alfa 2/metabolismo , Humor Aquoso/metabolismo , Tartarato de Brimonidina/metabolismo , Estabilidade de Medicamentos , Humanos
17.
Bioorg Chem ; 87: 209-217, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30901676

RESUMO

Rhamnolipids are biodegradable low toxic biosurfactants which exert antimicrobial and anti-biofilm properties. They have attracted much attention recently due to potential applications in areas of bioremediation, therapeutics, cosmetics and agriculture, however, the full potential of these versatile molecules is yet to be explored. Based on the facts that many naturally occurring lipopeptides are potent antimicrobials, our study aimed to explore the potential of replacing rhamnose in rhamnolipids with amino acids thus creating lipopeptides that would mimic or enhance properties of the parent molecule. This would allow not only for more economical and greener production but also, due to the availability of structurally different amino acids, facile manipulation of physico-chemical and biological properties. Our synthetic efforts produced a library of 43 lipopeptides revealing biologically more potent molecules. The structural changes significantly increased, in particular, anti-biofilm properties against Candida albicans, although surface activity of the parent molecule was almost completely abolished. Our findings show that the most active compounds are leucine derivatives of 3-hydroxy acids containing benzylic ester functionality. The SAR study demonstrated a further increase in activity with aliphatic chain elongation. The most promising lipopeptides 15, 23 and 36 at 12.5 µg/mL concentration allowed only 14.3%, 5.1% and 11.2% of biofilm formation, respectively after 24 h. These compounds inhibit biofilm formation by preventing adhesion of C. albicans to abiotic and biotic surfaces.


Assuntos
Antibacterianos/farmacologia , Antifúngicos/farmacologia , Candida albicans/efeitos dos fármacos , Glicolipídeos/farmacologia , Lipopeptídeos/farmacologia , Antibacterianos/síntese química , Antibacterianos/química , Antifúngicos/síntese química , Antifúngicos/química , Biofilmes/efeitos dos fármacos , Adesão Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Glicolipídeos/síntese química , Glicolipídeos/química , Lipopeptídeos/síntese química , Lipopeptídeos/química , Testes de Sensibilidade Microbiana , Estrutura Molecular , Biblioteca de Peptídeos , Pseudomonas aeruginosa/efeitos dos fármacos , Relação Estrutura-Atividade
18.
Artigo em Inglês | MEDLINE | ID: mdl-30669347

RESUMO

Background: Cadmium and lead are widespread and non-biodegradable pollutants of great concern to human health. In real life scenarios, we are exposed to mixtures of chemicals rather than single chemicals, and it is therefore of paramount importance to assess their toxicity. In this study, we investigated the toxicity of Cd and Pb alone and as a mixture in an animal model of acute exposure. Methods: Experimental groups received a single treatment of aqueous solution of Cd-chloride (15 and 30 mg/kg body weight (b.w.) and Pb-acetate (150 mg/kg b.w.), while the mixture group received 15 mg Cd/kg b.w. and 150 mg Pb/kg b.w. Toxic effects of individual metals and their mixture were investigated on hematological and biochemical parameters, and the redox status in the plasma, liver, and kidneys of treated Wistar rats. Results: Tissue-specific changes were recorded in various parameters of oxidative damage, while the accumulation of metals in tissues accompanied the disturbances of both hematological and biochemical parameters. It was observed that the level of toxic metals in tissues had a different distribution pattern after mixture and single exposure. Conclusions: Comprehensive observations suggest that exposure to Cd and Pb mixtures produces more pronounced effects compared to the response observed after exposure to single metal solutions. However, further research is needed to confirm toxicokinetic or toxicodynamic interactions between these two toxic metals in the organisms.


Assuntos
Cádmio/toxicidade , Poluentes Ambientais/toxicidade , Rim/efeitos dos fármacos , Chumbo/toxicidade , Fígado/efeitos dos fármacos , Animais , Cádmio/sangue , Cádmio/farmacocinética , Poluentes Ambientais/sangue , Poluentes Ambientais/farmacocinética , Rim/metabolismo , Chumbo/sangue , Chumbo/farmacocinética , Fígado/metabolismo , Masculino , Especificidade de Órgãos , Estresse Oxidativo , Ratos Wistar , Testes de Toxicidade Aguda
19.
Curr Med Chem ; 26(16): 2948-2961, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-29532755

RESUMO

Homocysteine (Hcy) is a thiol group containing the amino acid, which naturally occurs in all humans. Hcy is degraded in the body through two metabolic pathways, while a minor part is excreted through kidneys. The chemical reactions that are necessary for degradation of Hcy require the presence of folic acid, vitamins B6 and B12. Consequently, the level of the total Hcy in the serum is influenced by the presence or absence of these vitamins. An elevated level of the Hcy, hyperhomocysteinemia (HHcy) and homocystinuria is connected with occlusive artery disease, especially in the brain, the heart, and the kidney, in addition to venous thrombosis, chronic renal failure, megaloblastic anemia, osteoporosis, depression, Alzheimer's disease, pregnancy problems, and others. Elevated Hcy levels are connected with various pathologies both in adult and child population. Causes of HHcy include genetic mutations and enzyme deficiencies in 5, 10-methylenetetrahydrofolate reductase (MTHFR) methionine synthase (MS), and cystathionine ß-synthase (CßS). HHcy can be caused by deficiencies in the folate, vitamin B12 and to a lesser extent, deficiency in B6 vitamin what influences methionine metabolism. Additionally, HHcy can be caused by the rich diet and renal impairment. This review presents literature data from recent research related to Hcy metabolism and the etiology of the Hcy blood level disorder. In addition, we also described various pathological mechanisms induced by hereditary disturbances or nutritional influences and their association with HHcy induced pathology in adults and children and treatment of these metabolic disorders.


Assuntos
Homocisteína/metabolismo , Hiper-Homocisteinemia/etiologia , 5-Metiltetra-Hidrofolato-Homocisteína S-Metiltransferase/deficiência , 5-Metiltetra-Hidrofolato-Homocisteína S-Metiltransferase/genética , Animais , Deficiência de Vitaminas , Cistationina beta-Sintase/deficiência , Cistationina beta-Sintase/genética , Ácido Fólico/uso terapêutico , Humanos , Hiper-Homocisteinemia/tratamento farmacológico , Hiper-Homocisteinemia/genética , Metilenotetra-Hidrofolato Redutase (NADPH2)/deficiência , Metilenotetra-Hidrofolato Redutase (NADPH2)/genética , Vitamina B 12/uso terapêutico , Vitamina B 6/uso terapêutico
20.
Front Microbiol ; 8: 2454, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29276509

RESUMO

A new strain, namely Lysinibacillus sp. BV152.1 was isolated from the rhizosphere of ground ivy (Glechoma hederacea L.) producing metabolites with potent ability to inhibit biofilm formation of an important human pathogens Pseudomonas aeruginosa PAO1, Staphylococcus aureus, and Serratia marcescens. Structural characterization revealed di-rhamnolipids mixture containing rhamnose (Rha)-Rha-C10-C10, Rha-Rha-C8-C10, and Rha-Rha-C10-C12 in the ratio 7:2:1 as the active principle. Purified di-rhamnolipids, as well as commercially available di-rhamnolipids (Rha-Rha-C10-C10, 93%) were used as the substrate for the chemical derivatization for the first time, yielding three semi-synthetic amide derivatives, benzyl-, piperidine-, and morpholine. A comparative study of the anti-biofilm, antibacterial and cytotoxic properties revealed that di-Rha from Lysinibacillus sp. BV152.1 were more potent in biofilm inhibition, both cell adhesion and biofilm maturation, than commercial di-rhamnolipids inhibiting 50% of P. aeruginosa PAO1 biofilm formation at 50 µg mL-1 and 75 µg mL-1, respectively. None of the di-rhamnolipids exhibited antimicrobial properties at concentrations of up to 500 µg mL-1. Amide derivatization improved inhibition of biofilm formation and dispersion activities of di-rhamnolipids from both sources, with morpholine derivative being the most active causing more than 80% biofilm inhibition at concentrations 100 µg mL-1. Semi-synthetic amide derivatives showed increased antibacterial activity against S. aureus, and also showed higher cytotoxicity. Therefore, described di-rhamnolipids are potent anti-biofilm agents and the described approach can be seen as viable approach in reaching new rhamnolipid based derivatives with tailored biological properties.

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