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1.
Food Chem ; 332: 127384, 2020 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-32615384

RESUMO

Dairy polar lipids (PL) seem to exhibit antiplatelet effects. However, it is not known what molecular species may be responsible. In this study, we confirmed using C30 reversed-phase (C30RP) ultra-high-performance liquid chromatography (UHPLC) coupled to high resolution accurate mass tandem mass spectrometry (HRAM-MS/MS) that fermentation of yoghurts from ovine milk using specific starter cultures altered the PL composition. These lipid alterations occurred concomitant with increased antithrombotic properties of the yoghurts PL fractions against platelet-activating factor (PAF) and thrombin-induced platelet aggregation. Specifically, elevation in phosphatidylethanolamine (PE), sphingomyelin (SM), phosphatidylcholine (PC) and their molecular species were observed following yoghurt fermentation. Furthermore, PC(18:0/18:1), PE(18:1/18:2), SM(d18:0/22:0) and several other molecular species were significantly inversely correlated with the inhibition of PAF and thrombin. These molecular species were abundant in the most bioactive yoghurts fermented by S. thermophilus and L. acidophilus, which suggest that fermentation by these microorganisms increases the antithrombotic properties of ovine milk PL.


Assuntos
Lipídeos/análise , Leite/metabolismo , Inibidores da Agregação de Plaquetas/análise , Iogurte/análise , Animais , Plaquetas/efeitos dos fármacos , Plaquetas/metabolismo , Cromatografia Líquida de Alta Pressão , Fermentação , Lipídeos/farmacologia , Fosfatidilcolinas/metabolismo , Fosfatidiletanolaminas/metabolismo , Agregação Plaquetária/efeitos dos fármacos , Inibidores da Agregação de Plaquetas/farmacologia , Ovinos , Esfingomielinas/metabolismo , Espectrometria de Massas em Tandem , Trombina/farmacologia
2.
Int J Mol Med ; 45(2): 658-668, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31894254

RESUMO

Mineral­balanced deep sea water (MBDSW), an unlimited natural sea source, has been demonstrated to minimize the risk of developing cardiovascular diseases, such as obesity, hypertension, inflammation and hyperlipidemia. This study investigated the effects of MBDSW [magnesium (Mg):calcium (Ca) ratio, 3:1] on platelet activation. MBDSW significantly inhibited the collagen­ and thrombin­induced platelet aggregation of human platelets. In collagen­induced platelets, MBDSW inhibited intracellular calcium mobilization, granule secretion [serotonin, adenosine triphosphate (ATP) and P­selectin expression] and thromboxane A2 (TXA2) production. Moreover, MBDSW markedly inhibited Akt and extracellular signal­regulated kinase (ERK) phosphorylation, but not that of c­Jun N­terminal kinase (JNK) and p38. Moreover, MBDSW phosphorylated inositol 1,4,5­triphosphate receptor (IP3R) and vasodilator­stimulated phosphoprotein (VASP), and it increased the cyclic adenosine monophosphate (cAMP) level in collagen­induced human platelets. Dipyridamole, a phosphodiesterase (PDE) inhibitor, significantly increased the cAMP level and regulated the Akt, ERK and VASP (Ser157) levels in a manner similar to that of MBDSW. In addition, LY294002, an Akt inhibitor, inhibited the phosphorylation of ERK, and U0126, an ERK inhibitor, inhibited the phosphorylation of Akt. Taken together, the results of the present investigation suggest that the inhibitory effects of MBDSW on platelet aggregation may be associated with the cross­inhibition of Akt and ERK phosphorylation. These results strongly indicate that MBDSW may have preventive or therapeutic potential for platelet aggregation­mediated diseases, such as thrombosis, atherosclerosis and myocardial infarction.


Assuntos
Águas Minerais , Inibidores da Agregação de Plaquetas/farmacologia , Agregação Plaquetária/efeitos dos fármacos , Água do Mar , Plaquetas/citologia , Plaquetas/efeitos dos fármacos , Plaquetas/metabolismo , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Humanos , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Águas Minerais/análise , Inibidores da Agregação de Plaquetas/análise , Proteínas Proto-Oncogênicas c-akt/metabolismo , Água do Mar/análise , Transdução de Sinais/efeitos dos fármacos
3.
J Pharm Biomed Anal ; 179: 112955, 2020 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-31866139

RESUMO

Vicagrel is a promising novel antiplatelet drug. However, the quantification of vicagrel in plasma is currently unavailable since it is liable to be hydrolyzed in plasma by esterases. In this study, an optimized strategy was developed and validated to stabilize vicagrel, 2-oxo-clopidogrel (thiolactone metabolite), and H4 (active thiol metabolite) before quantification of the analytes, such as addition of citric acid (for plasma acidification) and NaF (a non-specific esterase inhibitor) to inhibit esterase activity, immediate addition of a thiol-alkylating reagent MPB into blood samples to derivatize H4 for the formation of stable H4 derivative (i.e., MP-H4), use of the anticoagulant K2EDTA to minimize the conversion of 2-oxo-clopidogrel to H-endo, and keeping the analytes at 4 °C or on wet ice to minimize degradation of the analytes when processed and analyzed. The stability was measured as percent of each analyte remained in plasma samples after their storage for 4 h at 4 °C or in blood samples after 1 h at 4 °C. The results indicated that stability of vicagrel was increased significantly in stabilized plasma or blood samples compared with non-stabilized controls for rats and humans, respectively, and that the stability of 2-oxo-clopidogrel was increased to a certain extent. In contrast, MP-H4 formed was stable in plasma immediately after thorough mixture of MPB with blood. We conclude that the above strategy is useful for improving the stability of vicagrel, 2-oxo-clopidogrel, and H4 in rat or human plasma, and that vicagrel and its two major metabolites can be quantified accurately and simultaneously.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Fenilacetatos/análise , Inibidores da Agregação de Plaquetas/análise , Espectrometria de Massas em Tandem/métodos , Tiofenos/análise , Animais , Feminino , Humanos , Masculino , Fenilacetatos/farmacocinética , Inibidores da Agregação de Plaquetas/farmacocinética , Ratos , Ratos Sprague-Dawley , Manejo de Espécimes , Temperatura , Tiofenos/farmacocinética , Fatores de Tempo
4.
Drug Dev Ind Pharm ; 45(9): 1515-1522, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31267803

RESUMO

Optimization of electrospray ionization (ESI) parameters is routinely carried out by one factor at a time (OFAT) or auto-tune software (ATS). Design of experiments (DOE) approach has been reported to be an excellent alternative to OFAT or ATS. Box-Behnken Design (BBD) was successfully used to optimize ESI parameters like nebulizing gas flow rate, desolvation line temperature, heat block temperature, and drying gas flow rate for [M + H]+ intensity of Clopidogrel bisulfate (CLP) and Ticlopidine (TLP). BBD model was found to be significant with p < .0001 for both CLP and TLP. The predicted and optimized (OL) ESI parameters were used for chromatographic analysis and were compared against three levels of ESI parameters, i.e. low level (LL), medium level (ML), and high level (HL). The OL ESI parameters were subjected to chromatographic analysis and its mean peak area was significantly higher than mean peak area for LL, ML, and HL ESI in case of CLP and TLP (p < .001). However, no significant difference was observed between the mean peak area for ML and OL of TLP. Thus, BBD can be considered with 29 trials to optimize four mass spectrometric parameters. The liquid chromatographic parameters percentage of methanol, percentage of formic acid and flow rate were also optimized using BBD. However, the optimized method did not significantly influence the peak response over the non-optimized method.


Assuntos
Inibidores da Agregação de Plaquetas/análise , Espectrometria de Massas por Ionização por Electrospray/métodos , Química Farmacêutica , Cromatografia Líquida de Alta Pressão/métodos , Clopidogrel/análise , Clopidogrel/química , Modelos Químicos , Inibidores da Agregação de Plaquetas/química , Sensibilidade e Especificidade , Ticlopidina/análise , Ticlopidina/química
5.
Luminescence ; 34(1): 64-69, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30537239

RESUMO

A spectrofluorimetric method for the determination of eptifibatide is presented based on its native fluorescence. The type of solvent and the wavelength of maximum excitation and emission were carefully selected to optimize the experimental conditions. Under the specified experimental conditions, the linearities obtained between the emission intensity and the corresponding concentrations of eptifibatide were in the range 0.1-2.5 µg/ml for the calibration curve constructed for direct determination of eptifibatide in dosage form and 0.05-2.2 µg/ml for the calibration curve constructed in spiked human plasma with a good correlation coefficient (r > 0.99). The lower limit of quantification for the calibration curve constructed in human plasma was 0.05 µg/ml. Recovery results for eptifibatide in spiked plasma samples and in dosage form, represented as mean ± % RSD, were 95.17 ± 1.94 and 100.29 ± 1.33 respectively. The suggested procedures were validated according to the International Conference on Harmonization (ICH) guidelines for the direct determination of eptifibatide in its pure form and dosage form and United States Food and Drug Administration (US FDA) Guidance for Industry, Bioanalytical Method Validation for the assay of eptifibatide in human plasma.


Assuntos
Eptifibatida/análise , Espectrometria de Fluorescência/métodos , Calibragem , Estabilidade de Medicamentos , Eptifibatida/sangue , Humanos , Limite de Detecção , Inibidores da Agregação de Plaquetas/análise , Inibidores da Agregação de Plaquetas/sangue , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Solventes/química , Temperatura
6.
J Pharm Biomed Anal ; 165: 346-356, 2019 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-30579235

RESUMO

The purpose of the present study is to develop a simple, rapid and sensitive stability-indicating high-performance liquid chromatography (HPLC) method for Clopidogrel Bisulfate (CBS) and further extending it for assessment of CBS stability in osmotic and pulsatile tablet formulations tested under accelerated conditions. A stability-indicating HPLC method for quantitative determination of CBS in gastro-retentive formulations is developed by using a C18 HPLC column, acetonitrile and 0.1% formic acid (60:40 v/v) as mobile phase, with a flow rate of 0.9 mL/min, UV detection at 222 nm and subsequently validated. The key objective was to analyze the stability profile of formulations under accelerated conditions. The retention time (Rt) of CBS was observed as 5.9 min with the linearity range between 0.06-1.95 µg/mL. Forced degradation studies were performed on bulk samples of CBS using acidic, basic, oxidative, thermal (80 °C) and photolytic (under sunlight) conditions. The resulting method was validated as per ICH Q2(R1) guidelines. Moreover, an attempt has been made to identify the degradation products by Liquid chromatography-mass spectrometry (LC-MS) analysis. The proposed method was successfully applied to novel gastro-retentive tablet formulations (osmotic tablet and pulsatile tablet) for assessment of stability under accelerated conditions.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Clopidogrel/análise , Inibidores da Agregação de Plaquetas/análise , Cromatografia Líquida/métodos , Clopidogrel/química , Preparações de Ação Retardada , Estabilidade de Medicamentos , Espectrometria de Massas/métodos , Osmose , Inibidores da Agregação de Plaquetas/química , Comprimidos , Fatores de Tempo
8.
Clin Toxicol (Phila) ; 56(12): 1200-1203, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-29889575

RESUMO

BACKGROUND: Ticagrelor is a direct and reversible competitive antagonist of the P2Y12 receptor and inhibits platelet activation. Although adverse bleeding is common, fatal intoxication has never been documented. CASE DESCRIPTION: A 47-year-old man died from a severe cerebral hemorrhage secondary to a fall and cranial trauma 4 d after the massive intake of ticagrelor. Iterative platelet transfusions did not improve his condition. Toxicological analyses by liquid chromatography tandem mass spectrometry (LC-MS/MS) revealed high plasma concentrations of ticagrelor (3343 µg/L) and its active metabolite AR-C124910XX (656 µg/L) 10 h after intake. The approximate ingested dose was extrapolated to 1677 mg. Assessment of ADP-induced platelet aggregation and platelet Vasodilator Stimulated Phosphoprotein phosphorylation (VASP), 2 and 3 d after admission, respectively, showed the persistence of platelet inhibition. DISCUSSION: To the best of our knowledge, no prior fatal cases have been reported and documented with both ticagrelor and AR-C124910XX concentrations. Our findings highlight the need for a specific antidote to manage such complications resulting from ticagrelor overdose.


Assuntos
Antídotos/uso terapêutico , Hemorragia Cerebral/induzido quimicamente , Inibidores da Agregação de Plaquetas/envenenamento , Antagonistas do Receptor Purinérgico P2Y/envenenamento , Ticagrelor/envenenamento , Acidentes por Quedas , Hemorragia Cerebral/diagnóstico por imagem , Hemorragia Cerebral/terapia , Evolução Fatal , Hemostasia , Humanos , Masculino , Pessoa de Meia-Idade , Inibidores da Agregação de Plaquetas/análise , Transfusão de Plaquetas , Antagonistas do Receptor Purinérgico P2Y/análise , Espectrometria de Massas em Tandem , Ticagrelor/análise , Tomografia Computadorizada por Raios X
9.
J Microencapsul ; 35(3): 229-240, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29644910

RESUMO

Grapes (Vitis vinifera) are produced in large amounts worldwide and mostly are used for winemaking. Their untreated wastes are rich in valuable secondary metabolites, such as phenolics. Thus, in this study, white and red wine wastes (Malagouzia and Syrah variety) were investigated for their added value phenolics, which were analysed by high performance liquid chromatography (HPLC) and electrospray ionisation-mass spectrometry (ESI/MS) and subsequently encapsulated in several polymers. Extracts from all wastes gave high amounts of total phenolics (13 ± 2.72-22 ± 2.69 mg g-1) and possessed high antioxidant activity (67-97%). In addition to their significant antibacterial activity against gram-negative and gram-positive bacteria, interesting results were also obtained from their anti-inflammatory and antiplatelet activity, in vitro. Encapsulation of the extracts was selective, leaving out most of sugars and other organic compounds when alginate-chitosan was used. Encapsulation efficiency recorded for all extracts ranged from 55% to 79%. Release studies were also performed in several solutions aiming in their commercial use in food and pharmaceutical industries.


Assuntos
Alginatos/química , Antioxidantes/análise , Quitosana/química , Portadores de Fármacos/química , Fenóis/análise , Fenóis/farmacologia , Vinho/análise , Adulto , Antibacterianos/administração & dosagem , Antibacterianos/análise , Antibacterianos/farmacologia , Anti-Inflamatórios/administração & dosagem , Anti-Inflamatórios/análise , Anti-Inflamatórios/farmacologia , Antioxidantes/administração & dosagem , Antioxidantes/farmacologia , Cápsulas/química , Cromatografia Líquida de Alta Pressão , Composição de Medicamentos , Liberação Controlada de Fármacos , Feminino , Ácido Glucurônico/química , Ácidos Hexurônicos/química , Humanos , Masculino , Microesferas , Pessoa de Meia-Idade , Fenóis/administração & dosagem , Inibidores da Agregação de Plaquetas/administração & dosagem , Inibidores da Agregação de Plaquetas/análise , Inibidores da Agregação de Plaquetas/farmacologia , Espectrometria de Massas por Ionização por Electrospray
10.
Eur J Pharm Sci ; 118: 208-215, 2018 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-29625210

RESUMO

Simultaneous analysis of drug compounds and their impurities of degradation and synthesis became constant in the modern pharmaceutical analysis. Likewise, analytical techniques must improve sensitivity and selectivity for the monitoring of pharmaceutical products, allowing a full assessment of impurities in drug products and, therefore, ensure safety and efficacy of pharmacological treatments. The application of Quality by Design (QbD) principles has proved to be feasible on the elaboration of analytical methods, allowing the comprehensive evaluation and measurement of different analytical parameters and their effects on critical properties of the methodology in development. QbD approach was applied to the development of a fast and selective HPLC method for the analysis of the antiplatelet aggregation drug ticagrelor and its degradation products in presence of three impurities of synthesis. Fractional factorial resolution V was the screening experimental design applied to five method parameters. Response surface methodology was carried by central composite star face design on the two critical method parameters selected. Analytical design space, established after the application of Monte-Carlo simulations, verified whether predicted results were in accordance with critical quality attributes. The developed and validated HPLC method with DAD detection at 225 nm was able to resolve eight related compounds in less than three minutes.


Assuntos
Adenosina/análogos & derivados , Cromatografia Líquida de Alta Pressão/métodos , Adenosina/análise , Contaminação de Medicamentos , Desenho de Fármacos , Estabilidade de Medicamentos , Inibidores da Agregação de Plaquetas/análise , Reprodutibilidade dos Testes , Ticagrelor
11.
Acta Trop ; 174: 122-129, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28690145

RESUMO

The saliva of hematophagous arthropods injected during blood feeding contains potent pharmacologically active components to counteract the host hemostatic and inflammatory systems. In the present study, dominant salivary gland transcripts of Panstrongylus chinai, a vector of Chagas disease, were analyzed by sequencing randomly selected clones of the salivary gland cDNA library. This analysis showed that 56.5% of the isolated transcripts coded for putative secreted proteins, of which 73.7% coded for proteins belonging to the lipocalin family. The most abundant transcript of lipocalin family proteins was a homologue of pallidipin 2, an inhibitor of collagen-induced platelet aggregation of Triatoma pallidipennis. In addition, homologues of triafestin, an inhibitor of the kallikrein-kinin system of T. infestans, were identified as the dominant transcript. Other salivary transcripts encoding lipocalin family proteins had homology to triplatin (an inhibitor of platelet aggregation) and others with unknown function. Other than lipocalin family proteins, homologues of a Kazal-type serine protease inhibitor (putative anticoagulant), a hemolysin-like protein (unknown function), inositol polyphosphate 5-related protein (a regulator of membrane phosphoinositide), antigen 5-related protein (unknown function) and apyrase (platelet aggregation inhibitor) were identified.


Assuntos
Vetores de Doenças , Inibidores da Agregação de Plaquetas/análise , Agregação Plaquetária/genética , Glândulas Salivares/fisiologia , Proteínas e Peptídeos Salivares/genética , Fatores de Transcrição/genética , Triatoma/genética , Sequência de Aminoácidos , Animais , Doença de Chagas/transmissão , Biblioteca Gênica
12.
J Pharm Biomed Anal ; 135: 206-216, 2017 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-28040655

RESUMO

A novel and generally applicable approach was established to hierarchically identify the bioactive components of a medicinal herb by preparative high-performance liquid chromatography (prep-HPLC) and a selective knock-out strategy. In this study, the targeted components of an herbal medicine were separated and knocked out using prep-HPLC. Subsequently, the contributions of the different target components to the overall effect of the medicinal herb were comparatively evaluated and differentiated by a heat map and a 3D score plot. This approach was successfully applied to investigate the bioactive constituents of safflower. The contributions of 11 components to the overall effect of safflower were as follows: anhydrosafflor yellow B (10)>6-hydroxykaempferol 3,6-di-O-ß-d-glucoside (8)>hydroxysafflor yellow A (3)>kaempferol 3-O-ß-rutinoside (11)>6-hydroxykaempferol 3-O-ß-rutinoside (9)>6-hydroxykaempferol 3,6-di-O-ß-d-glucoside-7-O-ß-d-glucuronide (4)>6-hydroxyapigenin 6-O-ß-d-glucoside-7-O-ß-d-glucuronide (6)>cytidine (1)>6-hydroxykaempferol 3-O-ß-rutinoside-6-O-ß-d-glucoside (7)>6-hydroxykaempferol 3,6,7-tri-O-ß-d-glucoside (5)>adenosine (2). These results demonstrate that quinochalcone C-glycosides (3 and 10) and some flavonoid glycosides containing C7-OH (such as 8, 9 and 11) made a greater contribution to the overall effect of safflower than the other components that were knocked out. The results provided an important reference for improving quality control and further development of safflower products. And this approach should also be useful for investigating the bioactive constituents of other medicinal herbs.


Assuntos
Anticoagulantes/análise , Antioxidantes/análise , Carthamus tinctorius , Química Farmacêutica/métodos , Extratos Vegetais/análise , Inibidores da Agregação de Plaquetas/análise , Animais , Anticoagulantes/farmacologia , Antioxidantes/farmacologia , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Cromatografia Líquida de Alta Pressão/métodos , Feminino , Flores , Masculino , Extratos Vegetais/farmacologia , Plantas Medicinais , Inibidores da Agregação de Plaquetas/farmacologia , Coelhos , Ratos , Ratos Sprague-Dawley
13.
Food Funct ; 7(9): 4075-4081, 2016 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-27713972

RESUMO

The effects of chronic administration of piceatannol-enriched (9.5% w/w) passion fruit seed extract (PFSE) on the cardiovascular damage induced in a high-fat (HF) diet-fed model of Fischer 344 rats were evaluated. Rats were fed the control, HF, or HF diets containing PFSE (0.5% w/w) for 16 weeks, and the effects of the various diets on the tissue weight, serum lipid profile, hepatic fibrosis, hepatic ductular reaction, cardiac function and aortic ring reactivity were examined. HF diet-fed rats developed signs of cardiovascular disease with abnormal serum profiles compared to control diet-fed rats. PFSE supplementation improved the liver hypertrophy and hepatic histology of the HF diet-fed rats. In addition, the triglyceride and cholesterol levels, platelet aggregation, cardiac function, and acetylcholine-mediated relaxation of the aortic ring were improved. These results suggest that the chronic intake of PFSE containing piceatannol prevents HF diet-induced cardiovascular disease in rats.


Assuntos
Doenças Cardiovasculares/prevenção & controle , Suplementos Nutricionais , Hipolipemiantes/uso terapêutico , Lipotrópicos/uso terapêutico , Hepatopatia Gordurosa não Alcoólica/prevenção & controle , Passiflora/química , Extratos Vegetais/uso terapêutico , Animais , Aorta/fisiopatologia , Doenças Cardiovasculares/etiologia , Doenças Cardiovasculares/patologia , Doenças Cardiovasculares/fisiopatologia , Dieta Hiperlipídica/efeitos adversos , Suplementos Nutricionais/análise , Ventrículos do Coração/patologia , Ventrículos do Coração/fisiopatologia , Hipolipemiantes/análise , Hipolipemiantes/química , Lipotrópicos/análise , Lipotrópicos/química , Fígado/patologia , Masculino , Hepatopatia Gordurosa não Alcoólica/etiologia , Hepatopatia Gordurosa não Alcoólica/patologia , Hepatopatia Gordurosa não Alcoólica/fisiopatologia , Tamanho do Órgão , Extratos Vegetais/química , Inibidores da Agregação de Plaquetas/análise , Inibidores da Agregação de Plaquetas/química , Inibidores da Agregação de Plaquetas/uso terapêutico , Distribuição Aleatória , Ratos Endogâmicos F344 , Sementes/química , Estilbenos/análise , Estilbenos/uso terapêutico , Resistência Vascular
14.
Pharm Biol ; 54(12): 3113-3120, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27558975

RESUMO

CONTEXT: The rising problem of atherosclerosis and ischemic heart disease emphasizes the need to look for new antithrombotic components with effective modes of action. Corydalis yanhusuo (Y.H. Chou & Chun C. Hsu) W.T. Wang ex Z.Y. Su & C.Y. Wu (Papaveraceae) (Rhizoma Corydalis) has been used in the traditional medicines for the treatment of cardiovascular disease. OBJECTIVE: The antiplatelet aggregation compounds in Rhizoma Corydalis were screened to validate its traditional medicinal use. MATERIAL AND METHODS: Total alkaloid extract (TAE) of Rhizoma Corydalis was obtained by refluxing 100 g Rhizoma Corydalis powder with 600 mL 70% ethanol, and purified by acidification (20% HCl) and alkalization (5 M NaOH) process. Potential antiplatelet aggregation compounds in TAE were screened by a method involving platelet bio-specific extraction and HPLC-DAD/LC-MS analysis. Further in vitro antiplatelet aggregation activity confirmation of TAE and seven main alkaloids were achieved by turbidimetry method within 3 h after blood collection from rabbit carotid artery, and all the test drugs were at the concentration range of 25-350 µg/mL. Finally, HPLC-DAD was employed for the quantitative determination of seven main components in TAE. RESULTS: Five alkaloids, identified as glaucine, dehydrocorydaline, canadine, tetrahydrocoptisine and corydaline, can be specifically extracted with platelets. The results indicated that all these five alkaloids can inhibit thrombin-induced platelet aggregation in a low dose (IC50 of glaucine, dehydrocorydaline, canadine, tetrahydrocoptisine and corydaline were 49.057, 34.914, 33.547, 84.261 and 54.164 µg/mL, respectively) as compared to TAE (IC50 = 175.426 µg/mL) and aspirin (IC50 = 300.340 µg/mL), while the unbound compounds (palmatine and tetrahydropalmatine) had a very weak antiplatelet effect (IC50 > 200 µg/mL). DISCUSSION AND CONCLUSION: This study is the first reported work for antiplatelet components screening in Rhizoma Corydalis. Seven compounds were detected and identified by HPLC-DAD/LC-MS, of which five platelet-targeted compounds were discovered.


Assuntos
Alcaloides/análise , Corydalis , Extratos Vegetais/análise , Inibidores da Agregação de Plaquetas/análise , Agregação Plaquetária/efeitos dos fármacos , Rizoma , Alcaloides/farmacologia , Animais , Extratos Vegetais/farmacologia , Agregação Plaquetária/fisiologia , Inibidores da Agregação de Plaquetas/farmacologia , Coelhos
15.
SEMERGEN, Soc. Esp. Med. Rural Gen. (Ed. Impr.) ; 42(5): 293-297, jul.-ago. 2016. tab
Artigo em Espanhol | IBECS | ID: ibc-154508

RESUMO

Introducción. Determinar el grado de asociación entre la terapia de antiagregación plaquetaria dual (TAAD) (clopidogrel y ácido acetilsalicílico) y el nivel de hemoglobina (Hb) en la práctica clínica. Material y métodos. Estudio retrospectivo. Se incluyeron todos los pacientes con TAAD durante al menos 6 meses, siendo el tamaño muestral necesario de 63 pacientes. Se determinó la Hb antes de la TAAD y el valor más próximo al cierre del estudio, la duración del tratamiento y las prescripciones o enfermedades que pudieran disminuir la Hb. Se calculó la variación de Hb tras TAAD y la aparición o empeoramiento de anemia previa. Se comparó la Hb previa y la posterior mediante prueba t para muestras apareadas. La aparición de anemia fue la variable dependiente en un análisis de regresión logística. Resultados. Se incluyeron 122 casos. Noventa y dos eran varones (75,4%), con una edad media de 74,5 (DE 9,9) años. La duración de la TAAD era de 19,3 (11,8) meses, siendo la Hb previa de 14,3 (1,4) y la posterior de 12,8 (1,9) g/dl. Había anemia pretratamiento en 11 casos (9,1%) y postratamiento en 56 (45,9%). La comparación de medias mostró un descenso de 1,5 (1,6) (IC95% 1,2-1,8; p<0,001) g/dl, asociándose la anemia postratamiento a la edad, causas concomitantes de anemia, hemorragias en el seguimiento y, de forma inversa, al nivel de Hb pretratamiento. Conclusiones. La TAAD se asocia con un descenso de la Hb, apareciendo anemia o empeoramiento de la misma en cerca de la mitad de los sujetos, y siendo este efecto más probable en los pacientes con hemorragias en el seguimiento y en presencia de otras causas de anemia (AU)


Introduction. To determine the degree of association between dual antiplatelet therapy (DAPT) (clopidogrel plus acetylsalicylic acid) and haemoglobin (Hb) in clinical practice. Material and methods. A retrospective longitudinal analysis was conducted on all patients on DAPT for at least 6 months. The required sample size was 63 patients. Hb value was determined before DAPT and at least 6 months after, as well as length of treatment, drugs, and diseases that might reduce the Hb. Changes in Hb after DAPT and the emergence or worsening of pre-existing anaemia was determined. Before and after Hb was compared using the t-test for paired samples. The occurrence of anaemia was considered dependent variable in a logistic regression analysis. Results. A total of 122 cases were included. There were 92 (75.4%) males, and the mean age was 74.5 (SD 9.9) years. DAPT duration was 19.3 (11.8) months. The pre-treatment Hb was 14.3 (1.4) g/dl and 12.8 (1.9) g/dl post-treatment. The prevalence of pre-DAPT anaemia was 9.1% (11 cases), and 45.9% post-treatment (56 cases). Comparison of means showed a decrease of 1.5g/dl (1.6) (95% CI; 1.2-1.8, P<.001). Anaemia post-treatment was associated with concomitant causes of anaemia, bleeding in the follow-up, and inversely with pre-treatment Hb level. Conclusions. DAPT is associated with a decrease in Hb. Anaemia or worsening of previous anaemia appeared in about half of the subjects, and this effect was most likely in patients with bleeding in the follow-up and if other causes of anaemia were present (AU)


Assuntos
Humanos , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Idoso , Estudos Observacionais como Assunto/métodos , Testes de Função Plaquetária/métodos , Inibidores da Agregação de Plaquetas/análise , Agregação Plaquetária/fisiologia , Hemoglobinas/análise , Aspirina/uso terapêutico , Terapia Combinada/métodos , Terapia Combinada , Estudos Retrospectivos , Análise de Regressão , Anemia/complicações , Anemia/tratamento farmacológico , Quimioterapia Combinada/instrumentação , Quimioterapia Combinada/métodos , Quimioterapia Combinada , Estudos Longitudinais
16.
Eur. j. anat ; 20(2): 121-130, abr. 2016. graf, ilus
Artigo em Inglês | IBECS | ID: ibc-152868

RESUMO

Platelets are blood cellular components involved in hemostatic processes and thrombus formation. Activation and inhibition of platelets result in an increase in morphological changes and a significant reduction in adhesion. There are several approaches towards the determination of the functional status of platelets, based on criteria such as cell adhesion, molecular changes at the cell surface, etc. In recent years, microfluidic devices have been introduced to mimic conditions proper to the vascular system, and so emulate thrombus formation in vivo. This study presents a microchip, the Thrombi Chip® , which is partially fitted with fluidic properties. This microchip has various types of micro-channels into which the platelets are inserted and, after drug treatment, the investigation is completed with the examination of the chip under an invert light microscope. For microscopy, cells were labeled with FCDA (human platelets) and Rho6G (mouse platelets). Counts and morphometric measurements of the adhered cells were carried out using digital images. To validate the results obtained with the microchip, the fractions of mice platelets were investigated with flow cytometry as well. Scanning electron microscopy was used to examine the morphological changes related to activation and inhibition in human platelets. The results show that, with this microchip, activation and inhibition of platelets can be detected. Flow cytometry studies largely confirm the microchip results. Certain variability in the results observed in human platelets is considered normal, as donors were randomized. In this respect the mouse platelets were much more uniform. Measurements with the microchip require that the sample be divided into three groups: control, activated and inhibited, resulting in a set of data, which, after respective evaluation, provides activity profiles, giving information on the status and response capacity of a sample. Such profiles could have diagnostic relevance and therefore be useful in a clinical context, for example in the monitoring of the effects of short- and long-term treatment of patients, as well as to test new drugs


No disponible


Assuntos
Humanos , Plaquetas/citologia , Técnicas Analíticas Microfluídicas/métodos , Ativação Plaquetária/fisiologia , Plaquetas/fisiologia , Hemostasia/fisiologia , Inibidores da Agregação de Plaquetas/análise , Trombose/fisiopatologia
17.
J Pharm Biomed Anal ; 117: 178-83, 2016 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-26355772

RESUMO

Platelets play crucial roles in thromboembolic and cardiovascular disease. The main platelets membrane receptors include adenosine diphosphate receptors, thrombin receptors, thromboxane prostanoid receptors and collagen receptors. In this study, a Platelet/CMC coupled with offline UPLC-QTOF-MS/MS system was built to screen antiplatelet activity components from aqueous extract of Danshen, which serve as an agent of antiplatelet aggregation in Traditional Chinese Medicine. Rosmarinic acid, lithospermic acid, salvianolic acid B, two isomers of salvianolic acid B, salvianolic acid C, salvianolic acid D and salvianolic acid H/I were identified as the potential antiplatelet activity components. Moreover, rosmarinic acid, lithospermic acid, salvianolic acid B, salvianolic acid C and danshensu were tested in platelet aggregation in vitro assay. The results suggested their retention time was closely related to the antiplatelet aggregation activities. This study provides a rapid, effective and novel method for screening the potential antiplatelet activity components from Chinese herb medicines.


Assuntos
Plaquetas/efeitos dos fármacos , Medicamentos de Ervas Chinesas/análise , Inibidores da Agregação de Plaquetas/análise , Salvia miltiorrhiza , Espectrometria de Massas em Tandem/métodos , Água/análise , Animais , Plaquetas/metabolismo , Cromatografia Líquida de Alta Pressão/métodos , Medicamentos de Ervas Chinesas/química , Medicamentos de Ervas Chinesas/farmacologia , Masculino , Inibidores da Agregação de Plaquetas/química , Inibidores da Agregação de Plaquetas/farmacologia , Ratos , Ratos Sprague-Dawley , Água/farmacologia
18.
Food Funct ; 6(8): 2845-53, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26189969

RESUMO

To elucidate the mechanism underlying the action of dietary vinegar on antithrombotic activity, acetic acid, the main acidic component of dietary vinegar, was used to determine antiplatelet and fibrinolytic activity. The results revealed that acetic acid significantly inhibits adenosine diphosphate (ADP)-, collagen-, thrombin-, and arachidonic acid (AA)-induced platelet aggregation. Acetic acid (2.00 mM) reduced AA-induced platelet aggregation to approximately 36.82 ± 1.31%, and vinegar (0.12 mL L(-1)) reduced the platelet aggregation induced by AA to 30.25 ± 1.34%. Further studies revealed that acetic acid exerts its effects by inhibiting cyclooxygenase-1 and the formation of thromboxane-A2. Organic acids including acetic acid, formic acid, lactic acid, citric acid, and malic acid also showed fibrinolytic activity; specifically, the fibrinolytic activity of acetic acid amounted to 1.866 IU urokinase per mL. Acetic acid exerted its fibrinolytic activity by activating plasminogen during fibrin crossing, thus leading to crosslinked fibrin degradation by the activated plasmin. These results suggest that organic acids in dietary vinegar play important roles in the prevention and cure of cardiovascular diseases.


Assuntos
Ácido Acético/metabolismo , Inibidores da Agregação de Plaquetas/metabolismo , Trombose/dietoterapia , Ácido Acético/análise , Adulto , Animais , Plaquetas , Ciclo-Oxigenase 1/metabolismo , Gerenciamento Clínico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Agregação Plaquetária , Inibidores da Agregação de Plaquetas/análise , Coelhos , Trombina/metabolismo , Trombose/enzimologia , Trombose/fisiopatologia , Trombose/prevenção & controle , Tromboxano A2/metabolismo , Adulto Jovem
19.
Artigo em Inglês | MEDLINE | ID: mdl-25703365

RESUMO

Most of mean centering (MCR) methods are designed to be used with data sets whose values have a normal or nearly normal distribution. The errors associated with the values are also assumed to be independent and random. If the data are skewed, the results obtained may be doubtful. Most of the time, it was assumed a normal distribution and if a confidence interval includes a negative value, it was cut off at zero. However, it is possible to transform the data so that at least an approximately normal distribution is attained. Taking the logarithm of each data point is one transformation frequently used. As a result, the geometric mean is deliberated a better measure of central tendency than the arithmetic mean. The developed MCR method using the geometric mean has been successfully applied to the analysis of a ternary mixture of aspirin (ASP), atorvastatin (ATOR) and clopidogrel (CLOP) as a model. The results obtained were statistically compared with reported HPLC method.


Assuntos
Anti-Inflamatórios não Esteroides/análise , Anticolesterolemiantes/análise , Aspirina/análise , Atorvastatina/análise , Inibidores da Agregação de Plaquetas/análise , Espectrofotometria/métodos , Ticlopidina/análogos & derivados , Clopidogrel , Distribuição Normal , Ticlopidina/análise
20.
Drug Dev Ind Pharm ; 41(4): 674-80, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24588740

RESUMO

A multiple-unit floating alginate bead drug delivery system with prolonged stomach retention time was developed in this study. The floating alginate beads were prepared by ionic cross-linking method, using CaCO3 as the gas-forming agent. Over 92% of the beads remained floating after 9 h. In order to prepare sustained-release dosage forms of dipyridamole, the solid dispersion technique was applied using a blend of Eudragit L100 and Eudragit RLPO. Afterwards, the solid dispersions of dipyridamole were incorporated into the floating alginate beads. The drug release was modified by changing the ratio of Eudragit RLPO and Eudragit L100 in the solid dispersions. The in vivo results showed that the relative bioavailability of alginate beads was enhanced by approximately 2.52-fold compared with that of the commercial tablet. Therefore, our study illustrated the potential use of floating alginate beads combined with the solid dispersion technique for the delivery of acid-soluble compounds, such as dipyridamole.


Assuntos
Dipiridamol/administração & dosagem , Sistemas de Liberação de Medicamentos , Excipientes/química , Suco Gástrico/química , Inibidores da Agregação de Plaquetas/administração & dosagem , Alginatos/química , Animais , Animais Endogâmicos , Disponibilidade Biológica , Varredura Diferencial de Calorimetria , Fenômenos Químicos , Preparações de Ação Retardada/administração & dosagem , Preparações de Ação Retardada/análise , Preparações de Ação Retardada/química , Preparações de Ação Retardada/farmacocinética , Dipiridamol/análise , Dipiridamol/química , Dipiridamol/farmacocinética , Cães , Composição de Medicamentos , Liberação Controlada de Fármacos , Ácido Glucurônico/química , Ácidos Hexurônicos/química , Concentração de Íons de Hidrogênio , Tamanho da Partícula , Inibidores da Agregação de Plaquetas/análise , Inibidores da Agregação de Plaquetas/química , Inibidores da Agregação de Plaquetas/farmacocinética , Ácidos Polimetacrílicos/química , Solubilidade
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