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1.
Medicina (Kaunas) ; 60(3)2024 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-38541225

RESUMO

Background and Objectives: Workplace burnout syndrome is often as sociated with particular aspects of certain job positions, especially those that entail working with people with special needs. The burnout syndrome in healthcare jobs is a serious problem that has grown into an epidemic among healthcare workers and associates. The aim of this research is to assess the presence of stress and burnout syndrome at work with healthcare workers, expert workers, professional associates, and associates in social service institutions in Belgrade. Materials and Methods: This research was conducted in the form of a cross-sectional study of a representative sample in social institutions in Belgrade. It was conducted from March to the end of June of 2023. The sample of the study had 491 participants. The questionnaires used were a structured instrument with social-demographic and social-economic characteristics, workplace characteristics, lifestyle characteristics, and the following questionnaires: DASS-21, Copenhagen, Brief Resilience Scale, and Brief Resilient Coping Scale. Results: The end results indicate the following to be significant risk factors for the occurrence of workplace burnout syndrome: overtime (OR = 2.62; CI = 1.50-4.56), BRS average score (OR = 0.28; CI = 0.17-0.44), DASS21 D heightened depression (OR = 2.09; CI = 1.1-4.04), DASS21 A heightened anxiety (OR = 2.38; CI = 1.34-4.21), and DASS21 S heightened stress (OR = 2.08; CI = 1.11-3.89). The only protective risk factor that stood out was the self-assessment of health levels (OR = 0.60; CI = 0.42-0.85). Conclusion: Overtime is a significant factor associated with workplace burnout. Apart from it, other significant factors associated with workplace burnout were heightened depression, anxiety, and stress levels.


Assuntos
Esgotamento Profissional , Pessoal de Saúde , Humanos , Estudos Transversais , Esgotamento Profissional/epidemiologia , Esgotamento Profissional/etiologia , Local de Trabalho , Inquéritos e Questionários , Serviço Social
2.
Food Technol Biotechnol ; 60(2): 213-224, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35910272

RESUMO

Research background: Acquisition of migratory potential is pivotal for cancer cells, enabling invasion and metastasis of colorectal carcinoma. Royal jelly and its bioactive component trans-10-hydroxy-2-decenoic acid (10H2DA) showed remarkable antimetastatic potential, but the molecular mechanism underlying this activity is unclear. Experimental approach: Identification and quantification of 10H2DA in royal jelly originating from Serbia was done by HPLC method. Cytotoxicity of 10H2DA was measured by tetrazolium dye MTT test in concentration range 1-500 µg/mL after 24 and 72 h. Its effect on the collective and single-cell migration was measured by wound healing and transwell migration assays. Invasive potential of cancer cells was evaluated by a transwell method modified with collagen. Immunofluorescence was used for migratory and invasive protein expression, while the gene expression of these markers was evaluated by quantitative real time polymerase chain reaction (qRT-PCR). All assays were applied on human colorectal carcinoma HCT-116 and SW-480 cell lines and, except for MTT, evaluated after 24 h of treatment with two selected concentrations of royal jelly and 10H2DA. Results and conclusions: According to HPLC, the mass fraction of 10H2DA in royal jelly was 0.92% (m/m). Treatment with 10H2DA showed no cytotoxic effect; however, significant inhibitory potential of royal jelly and 10H2DA on the motility and invasiveness of colorectal cancer cells was observed. More pronounced effect was exerted by 10H2DA, which significantly suppressed collective cell migration and invasiveness of SW-480 cells, as well as single- and collective cell migration and invasive potential of HCT-116 cell line. Treatments increased epithelial markers E-cadherin and cytoplasmic ß-catenin in HCT-116 cells, thus stabilizing intercellular connections. In SW-480 cells, 10H2DA increased E-cadherin on protein and gene level, and suppressed epithelial-mesenchymal transition (EMT) markers. In both cell lines, treatments induced significant suppression of promigratory/proinvasive markers: N-cadherin, vimentin and Snail on protein and gene level, which explains decreased migratory and invasive potential of HCT-116 and SW-480 cells. Novelty and scientific contribution: Our study presents new findings and elucidation of royal jelly and 10H2DA molecular mechanism that underlies their antimigratory/antiinvasive activity on colorectal cancer cells. These findings are shown for the first time indicating that these natural products are a valuable source of anticancer potential and should be reconsidered for further antitumour therapy.

3.
Anim Biotechnol ; 31(3): 195-202, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30795724

RESUMO

Insect silk has been widely studied for its application in regenerative medicine. However, the data about Plodia interpunctella silk as a biomaterial and its anticancer properties are insufficient. Thus, the aim of this study was to investigate native silk as a substrate for growing normal human fibroblasts MRC-5, and test potential cytotoxic effects of the two silk extracts (with DMSO and Trypsin for sericin isolation) on HCT-116 colorectal carcinoma cells and MRC-5 fibroblasts as a control. Fifth-instar larval silk, collected for 15 and 30 days, was used for testing of proliferation and adhesion of MRC-5, 24 h and 72 h after seeding. Light- and fluorescence-microscope showed cell adhesion and spread on silk, as well as enhanced number of cells after 72 compared to 24 h and nonsignificant percentage of apoptotic cells on the silk. Although insoluble, P. interpunctella silk showed remarkable cytotoxic activity on HCT-116 cells, without significant cytotoxity on normal fibroblasts after 24 h and weak effects after 72 h. This study provides significant information about P. interpunctella silk as a potential biomaterial and shows the presence of some active constituents with anticancer properties, thus pointing to the possibility for exploitation of this worldwide pest insect in biomedical application.


Assuntos
Antineoplásicos , Materiais Biocompatíveis , Seda , Animais , Antineoplásicos/química , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Adesão Celular/efeitos dos fármacos , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Fibroblastos/citologia , Fibroblastos/efeitos dos fármacos , Células HCT116 , Humanos , Mariposas , Sericinas , Seda/química , Seda/farmacologia
4.
J Biol Inorg Chem ; 24(7): 1057-1076, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31489480

RESUMO

In this study, we have synthesized a series of dinuclear and trinuclear gold(III) complexes of the general formula [Au2(N-N)Cl6] (1-3) for dinuclear and [Au3(N-N)2Cl8]+ (4-6) for trinuclear compounds, respectively, in which N-N is a bidentate ligand (1,4-diaminobutane; 1,6-diaminohexane or 1,8-diaminooctane). These complexes were characterized by elemental analysis, molar conductivity, and spectroscopic techniques (IR, UV-Vis, 1H NMR, ESI-MS). We performed DFT calculations to get insight into the geometry of the studies complexes. DNA-binding studies were performed by UV-Vis spectrophotometry and fluorescence spectroscopy. The results of competitive reactions between gold(III) complexes and ethidium bromide (EB) towards DNA have shown that selected complexes can displace EB from DNA-EB adduct. In addition, these experiments confirm that polynuclear gold(III) complexes interact with DNA covalently or via intercalation. Furthermore, high values of binding constants of gold(III) complexes towards bovine serum albumin (BSA) protein indicate good binding affinity. In addition, redox stability of complexes in the presence of DNA/BSA was confirmed by cyclic voltammetry. Results of the interactions between gold(III) complexes with DNA/BSA were discussed in reference to molecular docking data obtain by Molegro virtual docker. The cytotoxic activity of synthesized gold(III) complexes was evaluated on human breast cancer cell line (MDA-MB-231), human colorectal cancer cell line (HCT-116), and normal human lung fibroblast cell line (MRC-5). All complexes dose-dependently reduced cancer and normal cells viabilities, with significant cytotoxic effects (IC50 < 25 µM) for trinuclear gold(III) complexes (4, 5) on HCT-116 cells.


Assuntos
DNA/metabolismo , Teoria da Densidade Funcional , Ouro/química , Compostos Organoáuricos/síntese química , Compostos Organoáuricos/farmacologia , Soroalbumina Bovina/metabolismo , Antineoplásicos/síntese química , Antineoplásicos/química , Antineoplásicos/metabolismo , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Técnicas de Química Sintética , DNA/química , Eletroquímica , Humanos , Simulação de Acoplamento Molecular , Conformação de Ácido Nucleico , Compostos Organoáuricos/química , Compostos Organoáuricos/metabolismo
5.
Clin Exp Hypertens ; 40(3): 281-286, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-28920713

RESUMO

In this study, we tested a hypothesis that a short-term estradiol therapy may reduce blood pressure in preeclampsia by modulating plasma oxidative stress. The intramuscular injections of 10 mg 17-beta-estradiol were prescribed to preeclamptic pregnant women during the 3-day therapy before a labor induction. The analyses of mean arterial pressure (MAP), serum estradiol concentrations, plasma superoxide anion (O2.), hydrogen peroxide (H2O2), nitrites (NO2-), and peroxynitrite (ONOO-) were conducted before and during the therapy. We found that the plasma concentrations of oxidative stress markers, such as O2- and H2O2, are higher in preeclampsia and positively correlated with the MAP value. Moreover, it was shown that the plasma concentration of NO2- as an indicator of NO levels is higher in preeclampsia. A short-term intramuscular application of estradiol decreases the MAP value and the plasma concentration of O.-, H2O2, NO2-, and ONOO- in preeclampsia. A positive correlation between the decrease of MAP values and the decrease of plasma concentrations of O2-, H2O2, and ONOO- was found in preeclampsia during a short-term estradiol therapy. We conclude that the short-term estradiol therapy decreases the MAP value in preeclampsia by modulating the plasma oxidative stress. We speculate that the estradiol metabolism in preeclampsia is an important mechanism that contributes to vascular dysfunction.


Assuntos
Pressão Arterial/efeitos dos fármacos , Estradiol/uso terapêutico , Estrogênios/uso terapêutico , Estresse Oxidativo/efeitos dos fármacos , Pré-Eclâmpsia/tratamento farmacológico , Adulto , Biomarcadores/sangue , Estradiol/sangue , Feminino , Humanos , Peróxido de Hidrogênio/sangue , Hipertensão , Nitritos/sangue , Oxirredução , Ácido Peroxinitroso/sangue , Pré-Eclâmpsia/sangue , Gravidez , Superóxidos/sangue , Adulto Jovem
6.
Food Technol Biotechnol ; 56(3): 421-430, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30510485

RESUMO

The aim of this study is to investigate cytotoxic, proapoptotic, antimigratory and pro-antioxidant effects of methanol, acetone and ethyl acetate extracts of lichens Pseudevernia furfuracea and Platismatia glauca on colorectal cancer (HCT-116 and SW-480) cell lines. We compared the cytotoxic effects on colorectal cancer cells with the effects obtained from normal human fibroblast (MRC-5) cell line. Tetrazolium (MTT) test evaluated the cytotoxic effects, Transwell assay evaluated cell migration, acridine orange/ethidium bromide (AO/EB) fluorescent method followed the apoptosis, while prooxidant/antioxidant effects were determined spectrophotometrically through concentration of redox parameters. The tested extracts showed considerable cytotoxic effect on cancer cells with no observable cytotoxic effect on normal cells. Ethyl acetate and acetone extract of P. furfuracea induced the highest cytotoxicity (IC50=(21.2±1.3) µg/mL on HCT-116, and IC50=(51.3±0.8) µg/mL on SW-480 cells, respectively, after 72 h), with noteworthy apoptotic and prooxidant effects, and antimigratory potential of methanol extract. P. glauca extracts induced cytotoxic effects on HCT-116 cells after 72 h (IC50<40 µg/mL), while only methanol and acetone extracts had cytotoxic effects on SW-480 cells after 24 h, with proapoptotic/necrotic activity, as a consequence of induced oxidative stress. In conclusion, lichen extracts changed to a great extent cell viability and migratory potential of colorectal cancer cell lines. HCT-116 cells were more sensitive to treatments, P. furfuracea had better proapoptotic and antimigratory effects, and both investigated lichen species might be a source of substances with anticancer activity.

7.
Gen Physiol Biophys ; 36(2): 187-196, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28150586

RESUMO

Selenium and palladium containing compounds separately exert multifunctional effects on cells. While selenium containing compounds usually exert antioxidative properties, palladium(II) containing compounds are cytotoxic and prooxidative. Here we investigated biological effects of bicyclic seleno-hydantoin cis-7a-ethyl-5-methyl-5-phenylselanylmethyl-tetrahydro-pyrrolo[1,2-c]imidazole-1,3-dione (Hid-Se), and its palladium(II) complex, trans-bis-(cis-7a-ethyl-5-methyl-5-phenylselanylmethyl-tetrahydro-pyrrolo[1,2-c]imidazole-1,3-dionato) palladium(II) chloride ((Hid-Se)2Pd) on human colon HCT-116 and breast MDA-MB-231 cancer cell lines. Hid-Se and (Hid-Se)2Pd showed prooxidative and cytotoxic character. In all performed experiments (Hid-Se)2Pd proved to be more active, i.e. this substance exerted greater prooxidative effect, cytotoxicity and influence on cell migration potential. Even though Hid-Se and (Hid-Se)2Pd enhanced migration of HCT-116 cells, very important feature of these substances is the strong antimigratory potential on metastatic MDA-MB-231 cells.


Assuntos
Movimento Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Neoplasias Experimentais/tratamento farmacológico , Neoplasias Experimentais/fisiopatologia , Paládio/administração & dosagem , Selênio/administração & dosagem , Antineoplásicos/administração & dosagem , Relação Dose-Resposta a Droga , Composição de Medicamentos/métodos , Células HCT116 , Humanos , Hidantoínas/química , Neoplasias Experimentais/patologia , Oxidantes/administração & dosagem , Paládio/química , Espécies Reativas de Oxigênio/metabolismo , Selênio/química , Resultado do Tratamento
8.
Drug Dev Ind Pharm ; 43(3): 379-389, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27781496

RESUMO

We are presenting a new approach of identifying sources of variability within a manufacturing process by NIR measurements of samples of intermediate material after each consecutive unit operation (interprocess NIR sampling technique). In addition, we summarize the development of a multivariate statistical process control (MSPC) model for the production of enteric-coated pellet product of the proton-pump inhibitor class. By developing provisional NIR calibration models, the identification of critical process points yields comparable results to the established MSPC modeling procedure. Both approaches are shown to lead to the same conclusion, identifying parameters of extrusion/spheronization and characteristics of lactose that have the greatest influence on the end-product's enteric coating performance. The proposed approach enables quicker and easier identification of variability sources during manufacturing process, especially in cases when historical process data is not straightforwardly available. In the presented case the changes of lactose characteristics are influencing the performance of the extrusion/spheronization process step. The pellet cores produced by using one (considered as less suitable) lactose source were on average larger and more fragile, leading to consequent breakage of the cores during subsequent fluid bed operations. These results were confirmed by additional experimental analyses illuminating the underlying mechanism of fracture of oblong pellets during the pellet coating process leading to compromised film coating.


Assuntos
Química Farmacêutica/métodos , Implantes de Medicamento/análise , Lactose/análise , Controle de Qualidade , Espectroscopia de Luz Próxima ao Infravermelho/métodos , Química Farmacêutica/normas , Implantes de Medicamento/química , Implantes de Medicamento/normas , Liberação Controlada de Fármacos , Lactose/química , Lactose/normas , Análise Multivariada , Espectroscopia de Luz Próxima ao Infravermelho/normas
9.
Gen Physiol Biophys ; 33(4): 393-401, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25146184

RESUMO

The effects of nitroglycerin (glyceryl trinitrate - GTN) are mediated by liberated nitric oxide (NO) and formed reactive nitrogen species, which induces oxidative stress during biotransformation in red blood cells (RBCs). The aim of this study was to evaluate effects of GTN on antioxidative defense system (AOS) in rat erythrocytes (without) and reticulocytes (with functional mitochondria). Rat erythrocyte and reticulocyte-rich RBC suspensions were aerobically incubated (2 h, 37°C) without (control) or in the presence of different concentrations of GTN (0.1-1.5 mM). After incubation, concentrations of non-enzymatic components of AOS, activities of antioxidative enzymes and oxidative pentose phosphate (OPP) pathway activity were followed in RBC suspensions. In rat reticulocytes, GTN decreased the activity of mitochondrial MnSOD and increased the activity of CuZnSOD. In rat RBCs, GTN induced increase of Vit E concentration (at high doses), but decreased glutathione content and activities of all glutathione-dependent antioxidative enzymes; the OPP pathway activity significantly increased. GTN biotransformation and induction of oxidative stress were followed by general disbalance of antioxidative capacities in both kinds of RBCs. We suggest that oxidative stress, MnSOD inhibition and depletion of glutathione pool in response to GTN treatment lead to decreased bioavailability of NO after GTN biotransformation in rat reticulocytes.


Assuntos
Antioxidantes/metabolismo , Eritrócitos/efeitos dos fármacos , Eritrócitos/metabolismo , Nitroglicerina/metabolismo , Nitroglicerina/farmacologia , Reticulócitos/efeitos dos fármacos , Reticulócitos/metabolismo , Animais , Biotransformação , Relação Dose-Resposta a Droga , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Via de Pentose Fosfato/efeitos dos fármacos , Ratos
10.
J BUON ; 19(1): 283-90, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24659677

RESUMO

PURPOSE: To determine the antioxidant and antiproliferative influence of 2-(phenylselenomethyl)tetrahydrofuran (1a) and 2-(phenylselenomethyl)tetrahydropyran (2a) on colon cancer cell line HCT-116 and breast cancer cell line MDA-MB-231. METHODS: Cell viability was monitored in a dose-dependent manner using MTT assay. The concentration of superoxide anion radical (O2 •(-)) was determined spectrophotometrically. Spectrophotometric determination of nitrites (NO2 -) was performed by using the Griess method. Determination of total glutathione (GSH) was also performed spectrophotometrically. RESULTS: HCT-116 cell line was more sensitive to the effects of the investigated substances than MDA-MB-231 cell line. Also, it was noticed that 1a produced greater effect compared to 2a. Moreover, both investigated compounds decreased to a certain degree the oxidative stress by decreasing the O2•(-) and thus the peroxynitrite concentration. At the same time, 1a and 2a acted more efficiently in promoting the endogenous antioxidative capacities (increased GSH concentration) providing better self-defence capabilities for cells. CONCLUSION: Our findings showed that the investigated selenium compounds play an important role in reducing the levels of reactive oxygen species (ROS); therefore, we believe that, as antioxidants, they could prevent the processes arising as a consequence of oxidative stress, including cancer.


Assuntos
Antioxidantes/farmacologia , Furanos/farmacologia , Compostos Organosselênicos/uso terapêutico , Estresse Oxidativo/efeitos dos fármacos , Superóxidos/metabolismo , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Células HCT116 , Humanos , Espécies Reativas de Oxigênio/metabolismo
11.
Br J Sports Med ; 47(11): 701-4, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23322892

RESUMO

Recent positive doping cases and a series of mistakes of medical doctors of the International Federation of Basketball have reopened the debate about the role of medical doctor in elite sport. This study shows that some sports physicians involved in recent positive doping cases are insufficiently aware of the nuances of doping regulations and, most importantly, of the list of prohibited substances. Moreover, several team doctors are shown to have exercised poor judgement in relation to these matters with the consequence that athletes are punished for doping offences on the basis of doctors' negligence. In such circumstances, athletes' rights are jeopardised by a failure of the duty of care that (sports) physicians owe their athlete patients. We argue that, with respect to the World Anti Doping Code, antidoping governance fails to define, with sufficient clarity, the role of medical doctors. There is a need for a new approach emphasising urgent educational and training of medical doctors in this domain, which should be considered prior to the revision of the next World Anti Doping Code in 2013 in order to better regulate doctor's conduct especially in relation to professional errors, whether negligent or intentional.


Assuntos
Dopagem Esportivo/ética , Imperícia , Papel do Médico , Medicina Esportiva/normas , Basquetebol/legislação & jurisprudência , Competência Clínica/normas , Dopagem Esportivo/legislação & jurisprudência , Humanos , Relações Médico-Paciente/ética , Medicina Esportiva/ética
12.
Chem Biodivers ; 10(10): 1791-803, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24130023

RESUMO

To protect organisms from ionizing radiation (IR), and to reduce morbidity or mortality, various agents, called radioprotectors, have been utilized. Because radiation-induced cellular damage is attributed primarily to the harmful effects of free radicals, molecules with radical-scavenging properties are particularly promising as radioprotectors. Early development of such agents focused on thiol synthetic compounds, known as WR protectors, but only amifostine (WR-2721) has been used in clinical trials as an officially approved radioprotector. Besides thiol compounds, various compounds with different chemical structure were investigated, but an ideal radioprotector has not been found yet. Plants and natural products have been evaluated as promising sources of radioprotectors because of their low toxicity, although they exhibit an inferior protection level compared to synthetic thiol compounds. Active plant constituents seem to exert the radioprotection through antioxidant and free radical-scavenging activities. Our research established that plants containing polyphenolic compounds (raspberry, blueberry, strawberry, grape, etc.) exhibit antioxidative activities and protect genetic material from IR.


Assuntos
Lesões por Radiação/prevenção & controle , Protetores contra Radiação/química , Amifostina/química , Amifostina/uso terapêutico , Antioxidantes/química , Antioxidantes/uso terapêutico , Produtos Biológicos/química , Produtos Biológicos/uso terapêutico , Humanos , Plantas/química , Plantas/metabolismo , Polifenóis/química , Polifenóis/uso terapêutico , Protetores contra Radiação/uso terapêutico , Compostos de Sulfidrila/química , Compostos de Sulfidrila/uso terapêutico
13.
Molecules ; 18(3): 2469-82, 2013 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-23439563

RESUMO

The aim of the present study was to optimize a chromatographic method for the analysis of atorvastatin (acid and lactone forms), ortho- and para-hydroxyatorvastatin by using an experimental design approach. Optimization experiments were conducted through a process of screening and optimization. The purpose of a screening design is to identify the factors that have significant effects on the selected chromatographic responses, and for this purpose a full 23 factorial design was used. The location of the true optimum was established by applying Derringer's desirability function, which provides simultaneously optimization of all seven responses. The ranges of the independent variables used for the optimization were content of acetonitrile in mobile phase (60-70%), temperature of column (30-40 °C) and flow rate (0.8-1.2 mL min⁻¹). The influences of these independent variables were evaluated for the output responses: retention time of first peak (p-hydroxyatorvastatin) and of last peak (atorvastatin, lactone form), symmetries of all four peaks and relative retention time of p-hydroxyatorvastatin. The primary goal of this investigation was establishing a new simple and sensitive method that could be used in analysis of biological samples. The method was validated and successfully applied for determination of atorvastatin (acid and lactone forms) and its metabolites in plasma.


Assuntos
Anticolesterolemiantes/química , Cromatografia Líquida de Alta Pressão , Ácidos Heptanoicos/química , Pirróis/química , Algoritmos , Animais , Anticolesterolemiantes/farmacocinética , Atorvastatina , Cromatografia Líquida de Alta Pressão/métodos , Ácidos Heptanoicos/farmacocinética , Humanos , Redes e Vias Metabólicas , Modelos Químicos , Pirróis/farmacocinética , Ratos
14.
J Sci Food Agric ; 93(12): 3001-9, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23504630

RESUMO

BACKGROUND: Propolis is a complex resinous sticky substance that honeybees collect from buds and exudates of various plants. Owing to its versatile biological and pharmacological activities, propolis is widely used in medicines, cosmetics and foods. The aim of this study was to evaluate the cytotoxic and antioxidative effects of various ethanolic extracts of propolis (EEPs) on human colon cancer cell line HCT-116 and compare them with their composition determined by HPLC-DAD. RESULTS: The most abundant flavonoids in all samples were chrysin, pinocembrin and galangin (12.697-40.811 µg mg⁻¹), while the main phenolic acids were caffeic acid, ferulic acid and isoferulic acid. Dose- and time-dependent inhibition of growth of HCT-116 cells was observed for all propolis samples, with IC50 values ranging from 26.33 to 143.09 µg mL⁻¹. Differences in cytotoxic activity of propolis samples were associated with differences in their composition. All EEP samples reduced both superoxide anion radical and nitrite levels and also had strong DPPH-scavenging activity. CONCLUSION: All tested propolis samples had pronounced cytotoxic and antioxidative activities.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Antioxidantes/farmacologia , Produtos Biológicos/farmacologia , Neoplasias do Colo/tratamento farmacológico , Própole/química , Antineoplásicos Fitogênicos/química , Antioxidantes/química , Produtos Biológicos/química , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Cromatografia Líquida de Alta Pressão , Suplementos Nutricionais/análise , Etanol/química , Flavonoides/análise , Sequestradores de Radicais Livres/química , Sequestradores de Radicais Livres/farmacologia , Células HCT116 , Humanos , Concentração Inibidora 50 , Fenóis/análise , Sérvia , Solventes/química , Espectrofotometria Ultravioleta , Fatores de Tempo
15.
Artigo em Inglês | MEDLINE | ID: mdl-37453120

RESUMO

Introduction: Diabetic retinopathy (DR) is a microvascular complication of diabetes mellitus and the leading cause of visual impairment and blindness. The aim of the study was to estimate and compare the prevalence of DR and to determine an association between DR and systemic risk factors in hospitalized type 1 (DMT1) and type 2 (DMT2) diabetic patients. Material and methods: We analyzed 260 patients with diabetes, 43 with DMT1 and 217 with DMT2. The following data were collected: age, gender, type and duration of diabetes, glycemic control, blood pressure, estimated glomerular filtration rate, ophthalmologic examinations and routine biochemical parameters. Results: Out of the total number of 260 patients, 77 (29.6%) had non-proliferative DR (NPDR), 21 (8.1%) had proliferative DR (PDR), 29 (11.1%) had diabetic macular edema (DME), and 69 (23.5%) had diabetic cataracts. Forty-three (16.5%) patients were previously diagnosed with DMT1 and 217 (83.5%) with DMT2. The duration of diabetes was not significantly longer in DMT1 (12.8±11.2 years) in comparison to DMT2 (11.07±8.1 years). The prevalence of NPDR and PDR did not differ statistically in either groups. DME was more prevalent in DMT2 than in DMT1 (P<0.05). Diabetic cataract was found in 26.7% vs. 6.7% of patients with DMT2 and DMT1, respectively (p<0.01). The duration of diabetes significantly correlated with NPDR and PDR in DMT1 (r=o.31, p<0.05; r=0.55, p<0.001, respectively). In DMT2, significant correlations were found between the duration of diabetes and cataract, NPDR, PDR and DME (r=0.31, p<0.001; r=0.43 p<0.01, r=0.16 p<0.05 and r=0.20 p<0.01, respectively). Fasting plasma glucose (FPG) significantly correlated with PDR (r=0.258, p<0.05), while HbA1c with DME (r= 0.15 p<0.05). Conclusion: The duration of diabetes and hyperglycemia were associated with DR in both types of diabetes.


Assuntos
Diabetes Mellitus Tipo 2 , Retinopatia Diabética , Edema Macular , Humanos , Diabetes Mellitus Tipo 2/diagnóstico , Diabetes Mellitus Tipo 2/epidemiologia , Retinopatia Diabética/diagnóstico , Retinopatia Diabética/epidemiologia , Prevalência , Atenção Terciária à Saúde , Edema Macular/complicações , Edema Macular/epidemiologia , Fatores de Risco
16.
Polymers (Basel) ; 15(15)2023 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-37571062

RESUMO

Electrochemical crosslinking of alginate strands by in situ iron oxidation was explored using a potentiostatic regime. Carbon-based materials co-doped with iron, nitrogen, and/or sulfur were prepared via electrolyte composition variation with a nitrogen-rich compound (rivanol) or through post-treatments with sodium sulfide. Nanometer-sized iron particles were confirmed by transmission and field emission scanning electron microscopy in all samples as a consequence of the homogeneous dispersion of iron in the alginate scaffold and its concomitant growth-limiting effect of alginate chains. Raman spectra confirmed a rise in structural disorder with rivanol/Na2S treatment, which points to more defect sites and edges known to be active sites for oxygen reduction. Fourier transform infrared (FTIR) spectra confirmed the presence of different iron, nitrogen, and sulfur species, with a marked difference between Na2S treated/untreated samples. The most positive onset potential (-0.26 V vs. saturated calomel electrode, SCE) was evidenced for the sample co-doped with N, S, and Fe, surpassing the activity of those with single and/or double doping. The mechanism of oxygen reduction in 0.1 M KOH was dominated by the 2e- reduction pathway at low overpotentials and shifted towards complete 4e- reduction at the most negative explored values. The presented results put forward electrochemically formed alginate gels functionalized by homogeneously dispersed multivalent cations as an excellent starting point in nanomaterial design and engineering.

17.
Spectrochim Acta A Mol Biomol Spectrosc ; 301: 122987, 2023 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-37327500

RESUMO

Herein we unequivocally identify the mechanism of zeolite-catalysed thermal degradation of pesticide, employing Fourier-transform infrared spectroscopy (FTIR), Raman and mass spectrometry following temperature decomposition (TPDe/MS). We demonstrate that Y zeolite can effectively adsorb a significant amount of acetamiprid both in a single trial (168 mg/g) and in 10 cycles (1249 mg/g) with intermittent thermal regeneration at 300 °C. Sectional vibrational analysis of acetamiprid two-stage thermal degradation is performed for pristine and supported pesticide. The acetamiprid Raman spectral changes appear at 200 °C, while partial carbonization occurs at 250 °C. The gradual disappearance of the FTIR bands of acetamiprid is seen up to 270 °C when two Raman signature bands for carbonised material emerged. The TPDe/MS profiles reveal the evolution of mass fragments - in the first step, cleavage of the CC bond occurs between the aromatic core of the molecule and its tail-end, followed by cleavage of the CN bond. The mechanism of adsorbed acetamiprid degradation follows the same step, at significantly lower temperatures, as the process is catalysed by the interaction of acetamiprid nitrogens and zeolite support. Reduced temperature degradation allows for a quick recovery process that leaves 65% efficacy after 10 cycles. After numerous cycles of recovery, a subsequent one-time heat treatment at 700 °C completely restores initial efficacy. The efficient adsorption, novel details on degradation mechanism and ease of regeneration procedure place the Y zeolite at the forefront of future all-encompassing environmental solutions.


Assuntos
Praguicidas , Zeolitas , Zeolitas/química , Neonicotinoides , Temperatura
18.
Int J Mol Sci ; 13(2): 2521-2534, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22408469

RESUMO

The aim of this study is to examine the growth inhibitory effects of methanolic leaf and fruit extracts of L. vulgare on HCT-116 cells over different time periods and their synergistic effect with a Pd(apox) complex. The antiproliferative activity of plant extracts alone or in combination with the Pd(apox) complex was determined using MTT cell viability assay, where the IC(50) value was used as a parameter of cytotoxicity. Results show that antiproliferative effects of L. vulgare extracts increase with extension of exposure time, with decreasing IC(50) values, except for 72 h where the IC(50) values for methanolic leaf extract were lower than for the fruit extract. The Pd(apox) complex alone had a weak antiproliferative effect, but combination with L. vulgare extracts caused stronger effects with lower IC(50) values than with L. vulgare extracts alone. The type of cell death was explored by fluorescence microscopy using the acridin orange/ethidium bromide method. Treatments with plant extracts caused typical apoptotic morphological changes in HCT-116 cells and co-treatments with Pd(apox) complex caused higher levels of apoptotic cells than treatment with plant extracts alone. The results indicate that L. vulgare is a considerable source of natural bioactive substances with antiproliferative activity on HCT-116 cells and which have a substantial synergistic effect with the Pd(apox) complex.


Assuntos
Apoptose/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Ligustrum/química , Paládio/farmacologia , Extratos Vegetais/farmacologia , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/farmacologia , Relação Dose-Resposta a Droga , Células HCT116 , Humanos , Metanol/química , Extratos Vegetais/química , Folhas de Planta/química , Fatores de Tempo
19.
Artigo em Inglês | MEDLINE | ID: mdl-35451297

RESUMO

Background: Evidence for disturbances in HPA activation and abnormal HPA regulatory mechanisms in schizophrenia is accumulating. Aim: To compare serum levels of cortisol, DHEA-S and their ratio between patients with schizophrenia and healthy controls and among patients before and after treatment with different types of antipsychotics. Material and methods: In this clinical prospective study, 60 patients with schizophrenia and 40 healthy age and sex matched control subjects were included. All patients experienced an acute exacerbation of the illness (PANSS: P1 and P3 ≥ 4). Clinical evaluation of patients was performed using the Positive and Negative Symptom Scale. A questionnaire for socio-demographic and clinical data collection was used. Serum levels of cortisol, DHEA-S and their ratio were measured at baseline in all participants and after 3 and 6 weeks, respectively, of the antipsychotic treatment with different types of antipsychotics in patients with schizophrenia. Results: Patients with schizophrenia had significantly higher serum cortisol and DHEA-S levels in comparison to the control group. There was no significant difference in serum levels of cortisol, DHEA-S and their ratio between patients treated with different types of antipsychotics (typical/atypical). Serum levels of the analyzed hormones significantly reduce during the 6-week period of examination in both subgroups treated with different types of antipsychotics. Conclusion: Elevated serum cortisol and DHEA-S in schizophrenic patients might be associated with their role in the pathophysiology of the disorder. There is no significant difference in serum levels of cortisol, DHEA-S and their ratio among the patients treated with different types of antipsychotics.


Assuntos
Antipsicóticos , Esquizofrenia , Antipsicóticos/efeitos adversos , Sulfato de Desidroepiandrosterona/uso terapêutico , Humanos , Hidrocortisona/uso terapêutico , Estudos Prospectivos , Esquizofrenia/diagnóstico , Esquizofrenia/tratamento farmacológico
20.
J Ethnopharmacol ; 284: 114758, 2022 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-34688797

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Pseudevernia furfuracea (L.) Zopf is common lichen species, traditionally used worldwide in treating various medical conditions, among which are intestinal issues and cancer. Most studies are focused mainly on cytotoxic potential of lichens, whilst their antimigratory and antiinvasive properties are often disregarded. Migration and invasion of cancer cells are pivotal processes in cancer metastasis, wherein cancer cells are able to migrate individually or in form of a coherent mass. One of successful strategies in anticancer treatments is targeting Wnt/ß-catenin signal pathway, that is aberrantly activated in colorectal carcinoma, as well as lowering level of migratory/invasive markers. AIM OF THE STUDY: Present study aimed to show antimigratory/invasive potential of Pseudevernia furfuracea methanol extract on HCT-116 and SW-480 colorectal carcinoma cell lines and to elucidate possible mechanism of its action. MATERIALS AND METHODS: Collective cell migration was assessed by Wound healing assay and single cell migration in real time by RTCA method. Analysis of anti- and promigratory protein expression was performed using immunofluorescent staining. Additionally, gene expression of antimigratory/promigratory and invasive (E-cadherin, ß-catenin, N-cadherin, Vimentin, Snail and MMP-9) markers were investigated by qRT-PCR method. Concentration of MMP-9 was determined colorimetrically by ELISA test. RESULTS: P. furfuracea extract was able to suppress both collective and single cancer cell migration, by inhibiting expression of promigratory/invasive markers and possibly re-establishing cell-cell adhesions. The present study indicates at P. furfuracea as effective antimigratory treatment, and HCT-116 cells were proved to be a more sensitive cell line to applied treatment. CONCLUSIONS: This lichen species is a promising candidate for application in treatment of cancer in order to prevent metastasis.


Assuntos
Antineoplásicos/química , Antineoplásicos/farmacologia , Neoplasias Colorretais/metabolismo , Líquens , Linhagem Celular Tumoral , Movimento Celular , Fracionamento Químico , Neoplasias Colorretais/genética , Humanos , Medicina Tradicional , Cicatrização
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