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1.
Nat Prod Bioprospect ; 10(5): 307-316, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32852722

RESUMO

In Jordan, Salvia ceratophylla L. is traditionally used in the treatment of cancer, microbial infections, and urinary disorders. This study aimed: (1) to chemically characterize S. ceratophylla essential oil (EO) from South Jordan, by gas chromatography (GC) and gas chromatography-mass spectrometry (GC-MS); and (2) to evaluate in vitro the cytotoxic, anti-inflammatory, and antiprotozoal activities of the EO, it's predominant components, and the hexane (A), ethyl acetate (B), methanol (C) and crude-methanol extracts (D). The analysis revealed that the EO has 71 compounds, with linalool (54.8%) as main constituent. Only the hexane extract (A) showed some cytotoxic activity against SK-MEL, KB, BT-549, SK-OV-3, LLC-PK1 and VERO cells lines with IC50 between 60 and > 100 µg/mL. The EO inhibited NO production (IC50 90 µg/mL) and NF-κB activity (IC50 38 µg/mL). The extracts A, B, and D inhibited NO production and NF- κB activity with IC50 between 32 and 150 µg/mL. Linalool considerably inhibited NO production (IC50 18 µg/mL). The extracts tested did not exhibit antileishmanial activity. Regarding antitrypanosomal activity, the EO exhibited significant results with IC50 2.65 µg/mL. In conclusion, Jordan S. ceratophylla EO represents a rich source of linalool and bears a promising therapeutic potential for further antitrypanosomal drug development.

2.
BMC Pharmacol Toxicol ; 18(1): 40, 2017 06 02.
Artigo em Inglês | MEDLINE | ID: mdl-28577368

RESUMO

BACKGROUND: Protein ubiquitylation is an important post-translational regulation, which has been shown to be necessary for life cycle progression and survival of Plasmodium falciparum. Ubiquitin is a highly conserved 76 amino acid polypeptide, which attaches covalently to target proteins through combined action of three classes of enzymes namely, the ubiquitin-activating enzyme (E1), ubiquitin-conjugating enzyme (E2) and ubiquitin-protein ligase (E3). Ubiquitin E1 and E2 are highly conserved within eukaryotes. However, the P. falciparum E3 ligase is substantially variable and divergent compared to the homologs from other eukaryotes, which make the E3 ligase a parasite-specific target. METHODS: A set of selected E3 ubiquitin ligase inhibitors was tested in vitro against a chloroquine-sensitive P. falciparum D6 strain (PfD6) and a chloroquine-resistant P. falciparum W2 strain (PfW2). The inhibitors were also tested against Vero and transformed THP1 cells for cytotoxicity. The lead antimalarial E3 ubiquitin ligase inhibitors were further evaluated for the stage-specific antimalarial action and effects on cellular development of P. falciparum in vitro. Statistics analysis was done by two-way ANOVA followed by Tukey and Sidak multiple comparison test using GraphPad Prism 6. RESULTS: E3 ligase inhibitors namely, JNJ 26854165, HLI 373 and Nutlin 3 showed prominent antimalarial activity against PfD6 and PfW2. These inhibitors were considerably less cytotoxic to mammalian Vero cells. JNJ 26854165, HLI 373 and Nutlin 3 blocked the development of P. falciparum parasite at the trophozoite and schizont stages, resulting in accumulation of distorted trophozoites and immature schizonts. CONCLUSIONS: Interruption of trophozoites and schizont maturation by the antimalarial E3 ligase inhibitors suggest the role of ubiquitin/proteasome functions in the intraerythrocytic development of malaria parasite. The ubiquitin/proteasome functions may be critical for schizont maturation. Further investigations on the lead E3 ligase inhibitors shall provide better understanding regarding the importance of E3 ligase functions in the malaria parasite as a potential new antimalarial drug target and a new class of antimalarial drug leads.


Assuntos
Antimaláricos/farmacologia , Plasmodium falciparum/efeitos dos fármacos , Ubiquitina-Proteína Ligases/antagonistas & inibidores , Aminoquinolinas/farmacologia , Animais , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Chlorocebus aethiops , Humanos , Imidazóis/farmacologia , Piperazinas/farmacologia , Plasmodium falciparum/crescimento & desenvolvimento , Timina/análogos & derivados , Timina/farmacologia , Triptaminas/farmacologia , Células Vero
3.
Phys Chem Chem Phys ; 18(20): 14007-16, 2016 05 18.
Artigo em Inglês | MEDLINE | ID: mdl-27158697

RESUMO

The selective adsorption behaviours of carbon dioxide, methane and nitrogen on bundles of functionalized CMK-5 are investigated at 303 K using grand-canonical Monte Carlo simulations. Functional groups (-OH, -COOH) cause a significant enhancement in CO2 uptake (up to 19.5% at a pressure of 38.13 bar for -COOH). On the other hand, the adsorption amount of methane decreases with respect to bare CMK-5 by ∼13% (at 38.13 bar) upon functionalization. Furthermore, functionalized CMK-5 with different pore sizes (4 nm, 6 nm, 8 nm) and inter-tube distances (d = 0 to 1.5 nm) are used to investigate the adsorption behaviour of flue gases. While the pore diameter is seen to reduce the isosteric heat of adsorption, the inter-tube distance of 0.25 nm shows the highest uptake of CO2 at p ≤ 18 bar, followed by 0.5 nm for the pressure range of 18 < p ≤ 30 bar, whereas for p > 30 bar, d = 1.0 nm shows the maximum uptake. For methane and nitrogen, the maximum adsorption is obtained at d = 0.25 nm in the studied pressure range. The selective adsorption of CO2 in binary mixtures is investigated using ideal adsorption solution theory. CO2-N2 selectivity is found to increase significantly by surface functionalization of CMK-5 compared to pure CMK-5. The maximum selectivity of CO2-CH4 using -COOH functionalized CMK-5 is found to be ∼10 for an equimolar CO2-CH4 mixture at a pressure of 38.13 bar.

4.
Planta Med ; 80(18): 1706-11, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25340465

RESUMO

Leishmaniasis is a chronic infectious disease caused by different Leishmania species. Global occurrences of this disease are primarily limited to tropical and subtropical regions. Treatments are available; however, patients complain of side effects. Different species of plants have been screened as a potential source of new drugs against leishmaniasis. In this study, we investigated the antileishmanial activity of cilantro (Coriandrum sativum) essential oil and its main components: (E)-2-undecenal, (E)-2-decenal, (E)-2-dodecenal, decanal, dodecanal, and tetradecanal. The essential oil of C. sativum leaves inhibits growth of Leishmani donovani promastigotes in culture with an IC50 of 26.58 ± 6.11 µg/mL. The aliphatic aldehydes (E)-2-decenal (7.85 ± 0.28 µg/mL), (E)-2-undecenal (2.81 ± 0.21 µg/mL), and (E)-2-dodecenal (4.35 ± 0.15 µg/mL), all isolated from C. sativum essential oil, are effective inhibitors of in vitro cultures of L. donovani promastigotes. Aldehydes (E)-2-decenal, (E)-2-undecenal, and (E)-2-dodecenal were also evaluated against axenic amastigotes and IC50 values were determined to be 2.47 ± 0.25 µg/mL, 1.25 ± 0.11 µg/mL, and 4.78 ± 1.12 µg/mL, respectively. (E)-2-Undecenal and (E)-2-dodecenal demonstrated IC50 values of 5.65 ± 0.19 µg/mL and 9.60 ± 0.89 µg/mL, respectively, against macrophage amastigotes. These cilantro compounds showed no cytotoxicity against THP-1 macrophages.


Assuntos
Antiprotozoários/química , Antiprotozoários/farmacologia , Coriandrum/química , Leishmania donovani/efeitos dos fármacos , Aldeídos/química , Aldeídos/isolamento & purificação , Aldeídos/farmacologia , Alcenos/isolamento & purificação , Alcenos/farmacologia , Linhagem Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Avaliação Pré-Clínica de Medicamentos/métodos , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Concentração Inibidora 50 , Macrófagos/efeitos dos fármacos , Macrófagos/parasitologia , Estrutura Molecular , Óleos Voláteis/química , Óleos Voláteis/farmacologia
5.
Bioorg Med Chem Lett ; 24(15): 3247-50, 2014 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-24980054

RESUMO

A series of N-substituted tetrahydro-ß-carbolines were synthesized and screened for antileishmanial activity through an in vitro assay that involves promastigotes and axenic amastigotes of Leishmania donovani, the causative agent for visceral leishmaniasis. The thiophen-2-yl analogs 9b and 11f and naphthyl analog 11h were found to show significant activity against promastigotes with IC50 values of 12.7, 9.1 and 22.1 µM, respectively. Analogs 9b and 11h were also effective against axenic amastigotes with IC50 values of 62.8 and 87.6 µM, respectively. The antileishmanial activity of analogs was then tested in human macrophage cell line infected with L. donovani amastigotes and 2-naphthyl linked analog 11h was found to be effective with IC50 value of 28.3 µM. Several analogs also displayed antitrypanosomal activity against Trypanosoma brucei, the causative agent for human African trypanosomiasis. Compounds 11e, 11f and 11h were more effective than others with IC50 values of 1.0, 8.9 and 10.2 µM, respectively. All synthesized analogs were not cytotoxic towards mammalian cell lines including Vero (monkey kidney fibroblasts), HEPG2 (human hepatoma cells), LLC-PK1 (pig kidney epithelial cells) and THP-1 (human macrophages).


Assuntos
Antiprotozoários/farmacologia , Carbolinas/farmacologia , Leishmania donovani/efeitos dos fármacos , Trypanosoma brucei brucei/efeitos dos fármacos , Animais , Antiprotozoários/síntese química , Antiprotozoários/química , Carbolinas/síntese química , Carbolinas/química , Linhagem Celular , Chlorocebus aethiops , Relação Dose-Resposta a Droga , Células Hep G2 , Humanos , Macrófagos/efeitos dos fármacos , Macrófagos/parasitologia , Estrutura Molecular , Testes de Sensibilidade Parasitária , Relação Estrutura-Atividade , Suínos , Células Vero
6.
Tex Heart Inst J ; 39(5): 680-2, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23109767

RESUMO

Few cases of percutaneous device closure of a left ventricular pseudoaneurysm have been reported. We describe the case of a 67-year-old man with a history of coronary artery disease who presented with shortness of breath and chest pain. Computed tomographic angiography showed a left ventricular pseudoaneurysm that was filling from a small leak in the anterolateral aspect of the ventricle. The patient had undergone 3 previous sternotomies and was a high-risk candidate for surgical treatment of the pseudoaneurysm. Despite technical challenges, we closed the pseudoaneurysm percutaneously with use of a 6-mm AMPLATZER muscular ventricular septal defect occluder. The patient was released from the hospital the next day and was asymptomatic a year later.To our knowledge, this is the first report of the percutaneous closure of a left ventricular pseudoaneurysm via the femoral vein. We show that this manner of closure can be feasible in patients who have undergone multiple sternotomies and who are at high surgical risk.


Assuntos
Falso Aneurisma/terapia , Cateterismo Cardíaco , Aneurisma Cardíaco/terapia , Idoso , Falso Aneurisma/diagnóstico por imagem , Cateterismo Cardíaco/instrumentação , Angiografia Coronária/métodos , Veia Femoral/diagnóstico por imagem , Aneurisma Cardíaco/diagnóstico por imagem , Ventrículos do Coração , Humanos , Masculino , Desenho de Prótese , Dispositivo para Oclusão Septal , Tomografia Computadorizada por Raios X , Resultado do Tratamento
7.
Tex Heart Inst J ; 39(3): 416-9, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22719158

RESUMO

Stent thrombosis is a potentially lethal complication of percutaneous coronary intervention. We describe the case of a 51-year-old man who presented with acute anterior ST-segment-elevation myocardial infarction and underwent successful percutaneous transluminal coronary angioplasty and placement of 3 drug-eluting stents in the left anterior descending coronary artery. Despite receiving dual antiplatelet therapy, the patient presented a week later with a non-ST-segment-elevation myocardial infarction and was found to have nonocclusive thrombosis of the left anterior descending coronary artery stents and his ostial left main and left circumflex coronary arteries. Subsequently, bone marrow biopsy analysis indicated that the patient had acute myelogenous leukemia, which we believe was the underlying cause of his prothrombotic state and stent thrombosis.


Assuntos
Angioplastia Coronária com Balão/instrumentação , Infarto Miocárdico de Parede Anterior/terapia , Trombose Coronária/etiologia , Stents Farmacológicos , Leucemia Promielocítica Aguda/complicações , Angioplastia Coronária com Balão/efeitos adversos , Biópsia , Exame de Medula Óssea , Angiografia Coronária , Trombose Coronária/diagnóstico , Quimioterapia Combinada , Humanos , Leucemia Promielocítica Aguda/diagnóstico , Masculino , Pessoa de Meia-Idade , Inibidores da Agregação Plaquetária/uso terapêutico , Desenho de Prótese , Recidiva
8.
J Vis Exp ; (70)2012 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-23299097

RESUMO

Leishmaniasis is one of the world's most neglected diseases, largely affecting the poorest of the poor, mainly in developing countries. Over 350 million people are considered at risk of contracting leishmaniasis, and approximately 2 million new cases occur yearly(1). Leishmania donovani is the causative agent for visceral leishmaniasis (VL), the most fatal form of the disease. The choice of drugs available to treat leishmaniasis is limited (2);current treatments provide limited efficacy and many are toxic at therapeutic doses. In addition, most of the first line treatment drugs have already lost their utility due to increasing multiple drug resistance (3). The current pipeline of anti-leishmanial drugs is also severely depleted. Sustained efforts are needed to enrich a new anti-leishmanial drug discovery pipeline, and this endeavor relies on the availability of suitable in vitro screening models. In vitro promastigotes (4) and axenic amastigotes assays(5) are primarily used for anti-leishmanial drug screening however, may not be appropriate due to significant cellular, physiological, biochemical and molecular differences in comparison to intracellular amastigotes. Assays with macrophage-amastigotes models are considered closest to the pathophysiological conditions of leishmaniasis, and are therefore the most appropriate for in vitro screening. Differentiated, non-dividing human acute monocytic leukemia cells (THP1) (make an attractive) alternative to isolated primary macrophages and can be used for assaying anti-leishmanial activity of different compounds against intracellular amastigotes. Here, we present a parasite-rescue and transformation assay with differentiated THP1 cells infected in vitro with Leishmania donovani for screening pure compounds and natural products extracts and determining the efficacy against the intracellular Leishmania amastigotes. The assay involves the following steps: (1) differentiation of THP1 cells to non-dividing macrophages, (2) infection of macrophages with L. donovani metacyclic promastigotes, (3) treatment of infected cells with test drugs, (4) controlled lysis of infected macrophages, (5) release/rescue of amastigotes and (6) transformation of live amastigotes to promastigotes. The assay was optimized using detergent treatment for controlled lysis of Leishmania-infected THP1 cells to achieve almost complete rescue of viable intracellular amastigotes with minimal effect on their ability to transform to promastigotes. Different macrophage:promastigotes ratios were tested to achieve maximum infection. Quantification of the infection was performed through transformation of live, rescued Leishmania amastigotes to promastigotes and evaluation of their growth by an alamarBlue fluorometric assay in 96-well microplates. This assay is comparable to the currently-used microscopic, transgenic reporter gene and digital-image analysis assays. This assay is robust and measures only the live intracellular amastigotes compared to reporter gene and image analysis assays, which may not differentiate between live and dead amastigotes. Also, the assay has been validated with a current panel of anti-leishmanial drugs and has been successfully applied to large-scale screening of pure compounds and a library of natural products fractions (Tekwani et al. unpublished).


Assuntos
Avaliação Pré-Clínica de Medicamentos/métodos , Leishmania donovani/efeitos dos fármacos , Leishmania donovani/crescimento & desenvolvimento , Leucemia Monocítica Aguda/parasitologia , Antiprotozoários/farmacologia , Linhagem Celular Tumoral , Humanos , Leishmaniose Visceral/tratamento farmacológico , Leishmaniose Visceral/parasitologia , Leucemia Monocítica Aguda/patologia , Macrófagos/parasitologia , Macrófagos/patologia
9.
Planta Med ; 77(14): 1639-43, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21384317

RESUMO

A new indolizidine alkaloid, named Δ¹,6-juliprosopine (1), together with previously known indolizidine analogs (2- 6), was isolated from the leaves of Prosopis glandulosa var. glandulosa, collected from Nevada, USA; while two other known indolizidines, juliprosopine (6) and juliprosine (7), were isolated from P. glandulosa leaves collected in Texas, USA. The structures of compound 1 and 7 were determined using a combination of NMR and MS techniques. Compound 7 exhibited potent antiplasmodial activity against Plasmodium falciparum D6 and W2 strains with IC (50) values of 170 and 150 ng/mL, respectively, while 1 was found to be less active (IC50 values 560 and 600 ng/mL, respectively). Both compounds were devoid of VERO cells toxicity up to a concentration of 23 800 ng/mL. The antileishmanial activity of indolizidines was evaluated against Leishmania donovani promastigotes, axenic amastigotes, and amastigotes in THP1 macrophage cultures. When tested against macrophage cultures, the tertiary bases (1, 3, 6) were found to be more potent than quaternary salts (2, 5, 7), displaying IC50 values between 0.8-1.7 µg/mL and 3.1-6.0 µg/mL, respectively. In addition, compound 7 showed potent antifungal activity against Cryptococcus neoformans and antibacterial activity against Mycobacterium intracellulare, while 1 was potent only against C. neoformans and weakly active against other organisms.


Assuntos
Alcaloides/farmacologia , Anti-Infecciosos/farmacologia , Indolizidinas/farmacologia , Extratos Vegetais/química , Prosopis/química , Alcaloides/química , Animais , Anti-Infecciosos/química , Linhagem Celular , Chlorocebus aethiops , Cryptococcus neoformans/efeitos dos fármacos , Humanos , Indolizidinas/química , Concentração Inibidora 50 , Leishmania donovani/efeitos dos fármacos , Macrófagos/efeitos dos fármacos , Estrutura Molecular , Complexo Mycobacterium avium/efeitos dos fármacos , Folhas de Planta/química , Plantas Medicinais , Plasmodium falciparum/efeitos dos fármacos , Texas
10.
Nat Prod Commun ; 6(11): 1645-50, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22224279

RESUMO

The EtOH extract of Abrus schimperi (Fabaceae), collected in Kenya, demonstrated significant activity against Leishmania donovani promastigotes with IC50 value of 3.6 microg/mL. Bioassay-guided fractionation of CHCl3 fraction using Centrifugal Preparative TLC afforded two antiparasitic isoflavanquinones, namely amorphaquinone (1) and pendulone (2). They displayed IC50 values of 0.63 microg/mL and 0.43 microg/mL, respectively, against L. donovani promastigotes. Both the compounds were also evaluated against L. donovani axenic amastigotes and amastigotes in THPI macrophage cultures. In addition, compounds 1 and 2 showed antiplasmodial activity against Plasmodium falciparum D6 and W2 strains, while 2 displayed antibacterial activity against Staphylococcus aureus and methicillin-resistant S. aureus (each IC50 1.44 microg/mL). The 1H and 13C data of 1, not fully assigned previously, were unambiguously assigned using 1D and 2D NMR HMBC and HMQC experiments. In addition, the absolute stereochemistry of the isolated compounds 1 and 2 was revised as C-(3S) based on Circular Dichroism experiments. This appears to be the first report of amorphaquinone (1) and pendulone (2) from the genus Abrus.


Assuntos
Abrus/química , Anti-Infecciosos/isolamento & purificação , Antineoplásicos Fitogênicos/isolamento & purificação , Isoflavonas/isolamento & purificação , Quinonas/isolamento & purificação , Anti-Infecciosos/química , Antineoplásicos Fitogênicos/química , Linhagem Celular Tumoral , Dicroísmo Circular , Humanos , Isoflavonas/química , Espectroscopia de Ressonância Magnética , Testes de Sensibilidade Microbiana , Extratos Vegetais/química , Quinonas/química
11.
Langmuir ; 23(3): 1123-30, 2007 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-17241022

RESUMO

In atomistic models of amorphous materials, ring statistics provide a measure of medium-range order. However, while ring statistics tell us the number of rings present in the model, they do not give us any information about the arrangement of rings, e.g., whether the rings are clustered and how big the cluster is. In this work we present a method to calculate the ring connectivity, or clustering, of rings. We first calculate the rings present in the model using the shortest path criteria of Franzblau and then find the rings that are connected together and group them into clusters. We apply our method to a set of models of disordered carbons, obtained using a reverse Monte Carlo procedure developed in a recent work. We found that in these carbon models the five-, six-, and seven-membered rings are connected together, forming clusters. After isolating the clusters, we found that they resemble defective graphene segments twisted in a complex way. The clusters give further insight about the arrangement of carbon atoms in microporous carbons at a larger length scale. Moreover, the method can be applied to any network covalent solid that contains rings and thus gives information about the ring connectivity present in such materials.

12.
Langmuir ; 22(24): 9942-8, 2006 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-17106983

RESUMO

We apply a simulation protocol based on the reverse Monte Carlo (RMC) method, which incorporates an energy constraint, to model porous carbons. This method is called hybrid reverse Monte Carlo (HRMC), since it combines the features of the Monte Carlo and reverse Monte Carlo methods. The use of the energy constraint term helps alleviate the problem of the presence of unrealistic features (such as three- and four-membered carbon rings), reported in previous RMC studies of carbons, and also correctly describes the local environment of carbon atoms. The HRMC protocol is used to develop molecular models of saccharose-based porous carbons in which hydrogen atoms are taken into account explicitly in addition to the carbon atoms. We find that the model reproduces the experimental pair correlation function with good accuracy. The local structure differs from that obtained with a previous model (Pikunic, J.; Clinard, C.; Cohaut, N.; Gubbins, K. E.; Guet, J. M.; Pellenq, R. J.-M.; Rannou, I.; Rouzaud, J. N. Langmuir 2003, 19 (20), 8565). We study the local structure by calculating the nearest neighbor distribution, bond angle distribution, and ring statistics.


Assuntos
Carbono/química , Química/métodos , Simulação por Computador , Hidrogênio/química , Modelos Moleculares , Modelos Estatísticos , Modelos Teóricos , Método de Monte Carlo , Sacarose/química , Propriedades de Superfície , Termodinâmica
13.
Cardiovasc Dis ; 8(1): 29-38, 1981 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-15216223

RESUMO

Two-dimensional echocardiographic imaging of the mitral valve orifice was attempted in 26 patients with isolated mitral stenosis. The intention was to examine further the clinical usefulness and limitations of this technique for estimating the severity of mitral stenosis. Technically adequate recordings of the mitral orifice were obtained in 20 patients (77%). Mitral valve area calculated from echocardiography compared favorably to the valve area derived from cardiac catheterization with the use of the Gorlin formula (r = 0.95). The average difference between the two methods was 0.109 cm(2). Two-dimensional echocardiography does provide clinically useful data for predicting the degree of mitral stenosis in the majority of patients provided that critical technical limitations are recognized.

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