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1.
J Chem Inf Model ; 63(22): 7083-7096, 2023 Nov 27.
Artículo en Inglés | MEDLINE | ID: mdl-37917937

RESUMEN

Epilepsy is a neurological disorder characterized by recurrent seizures that arise from abnormal electrical activity in the brain. Voltage-gated sodium channels (NaVs), responsible for the initiation and propagation of action potentials in neurons, play a critical role in the pathogenesis of epilepsy. This study sought to discover potential anticonvulsant compounds that interact with NaVs, specifically, the brain subtype hNaV1.2. A ligand-based QSAR model and a docking model were constructed, validated, and applied in a parallel virtual screening over the DrugBank database. Montelukast, Novobiocin, and Cinnarizine were selected for in vitro testing, using the patch-clamp technique, and all of them proved to inhibit hNaV1.2 channels heterologously expressed in HEK293 cells. Two hits were evaluated in the GASH/Sal model of audiogenic seizures and demonstrated promising activity, reducing the severity of sound-induced seizures at the doses tested. The combination of ligand- and structure-based models presents a valuable approach for identifying potential NaV inhibitors. These findings may provide a basis for further research into the development of new antiseizure drugs for the treatment of epilepsy.


Asunto(s)
Anticonvulsivantes , Epilepsia , Humanos , Anticonvulsivantes/farmacología , Anticonvulsivantes/uso terapéutico , Células HEK293 , Ligandos , Epilepsia/tratamiento farmacológico , Convulsiones/tratamiento farmacológico , Canal de Sodio Activado por Voltaje NAV1.7
2.
Psicol. conoc. Soc ; 8(1): 139-166, mayo 2018. tab
Artículo en Español | LILACS-Express | LILACS | ID: biblio-1091797

RESUMEN

Resumen: Los constantes cambios en la sociedad en la que nos vemos inmersos conllevan la necesidad de investigar metodologías y recursos que supongan una mejora en el aprendizaje de los alumnos e incrementar su motivación. Dentro de los diferentes tipos de metodologías, existe la denominada metodología de aprendizaje basado en proyectos (ABP), la cual ofrece multitud de variantes que se pueden adaptar al sistema educativo actual y futuro. Para que la metodología basada en proyectos logre conectar con los estudiantes y consiga mejorar su rendimiento académico y su nivel motivacional, debe ser interesante y atractiva. Es por este hecho por el que se plantea el uso de un nuevo recurso educativo en las aulas utilizando dicha metodología. Ese recurso didáctico es la impresora 3D, debido a su gran variedad de oportunidades que ofrece para trabajar con ella en el aula y su futuro tan prometedor en diferentes campos profesionales. Con el presente trabajo se pretende por un lado, indagar en las bases teóricas que posicionan la impresión 3D junto con el aprendizaje basado en proyectos como una metodología que potencia la motivación del alumno y su aprendizaje significativo, y por el otro, hacer una propuesta metodológica que incluya los aspectos necesarios para poder llevar a cabo un proyecto de estas características en el aula.


Abstract: The current society in constant change where we are immersed requires to investigate methodologies and resources that suppose an improvement in the students´ learning process and an increase of their motivation. Within the different types of methodologies, there is one denominated Project-based learning (PBL), which offers a multitude of variants that are perfectly adapted to the current and future educational system. The project-based learning needs to be interesting and engaging to connect with students and improve their academic performance and motivational level. It is for this reason that the use of a new educational resource in the classrooms is proposed meanwhile this methodology is applied. This didactic resource is the 3D printer due to its wide variety of opportunities to work with it in the classroom and its promising future in different professional fields. The present work intends on the one hand to investigate the theoretical bases that position the 3D impression together with the project based learning as a methodology that enhances the motivation of the student and his significant learning and on the other hand to develop a methodological proposal that includes necessary aspects to be able to carry out a project of these characteristics in the classroom.


Resumo: A sociedade atual em constante mudança em que estamos imersos precisa investigar metodologias e recursos que supõem uma melhoria na aprendizagem dos alunos e aumentar sua motivação. Entre as várias metodologias encontra-se a denominada aprendizagem baseada em projetos (ABP), a qual oferece um vasto leque de opções que se adaptam perfeitamente ao sistema educativo atual e futuro. A fim de cativar os estudantes e de melhorar o seu rendimento académico e o seu nível motivacional, ametodologia baseada em projetos deverá ser interessante e atrativa. Perante este facto, propõe-se a adoção de um novo recurso educacional nas salas de aula que permitirá aplicar e desenvolver esta mesma metodologia. O dito recurso trata-se da impressora 3D dada a grande variedade de opções que oferece no trabalho em sala de aula e o seu promissor futuro em diferentes campos profissionais. No presente trabalho, pretende-se por um lado aferir as bases teóricas que posicionam a impressão 3D e a aprendizagem baseada em projetos como uma metodologia que potencia a motivação do aluno e a sua aprendizagem significativa, e por outro lado apresentar uma proposta metodológica que inclua os aspetos necessários para poder levar a cabo um projeto com estas características no contexto da aula.

3.
Molecules ; 19(12): 21044-65, 2014 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-25517343

RESUMEN

Amoebiasis caused by Entamoeba histolytica is associated with high morbidity and mortality is becoming a major public health problem worldwide, especially in developing countries. Because of the side-effects and the resistance that pathogenic protozoa build against the standard antiparasitic drugs, e.g., metronidazole, much recent attention has been paid to plants used in traditional medicine around the world in order to find new antiprotozoal agents. We collected 32 plants used in Northeast Mexican traditional medicine and the methanolic extracts of these species were screened for antiprotozoal activity against E. histolytica trophozoites using in vitro tests. Only 18 extracts showed a significant inhibiting activity and among them six plant extracts showed more than 80% growth inhibition against E. histolytica at a concentration of 150 µg/mL and the IC50 values of these extracts were determined. Lippia graveolens Kunth and Ruta chalepensis Pers. showed the more significant antiprotozoal activity (91.54% and 90.50% growth inhibition at a concentration of 150 µg/mL with IC50 values of 59.14 and 60.07 µg/mL, respectively). Bioassay-guided fractionation of the methanolic extracts from these two plants afforded carvacrol (1) and chalepensin (2), respectively, as bioactive compounds with antiprotozoal activity.


Asunto(s)
Amebicidas/farmacología , Entamoeba histolytica/efectos de los fármacos , Lippia/química , Extractos Vegetales/farmacología , Ruta/química , Amebicidas/aislamiento & purificación , Cimenos , Evaluación Preclínica de Medicamentos , Furocumarinas/aislamiento & purificación , Furocumarinas/farmacología , Concentración 50 Inhibidora , Medicina Tradicional , México , Monoterpenos/aislamiento & purificación , Monoterpenos/farmacología , Extractos Vegetales/aislamiento & purificación
4.
Biomed Res Int ; 2013: 679365, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-24024206

RESUMEN

Trichomoniasis is one of the most common acute sexually transmitted curable diseases, and it is disseminated worldwide generating more than 170 million cases annually. Trichomonas vaginalis is the parasite that causes trichomoniasis and has the ability to destroy cell monolayers of the vaginal mucosa in vitro. Sphingomyelinases (SMase) are enzymes that catalyze the hydrolysis of sphingomyelin into ceramide and phosphorylcholine. Ceramide appears to be a second messenger lipid in programmed apoptosis, cell differentiation, and cell proliferation. Sphingomyelinase is probably a major source of ceramide in cells. Signal transduction mediated by ceramide leads cells to produce cytokine induced apoptosis during several inflammatory responses. SMase are also relevant toxins in several microorganisms. The main objective of this research is to identify SMase activity of T. vaginalis in the total extract (TE), P30, and S30 subfractions from brooked trophozoites. It was found that these fractions of T. vaginalis have SMase activity, which comes principally from P30 subfraction and was mainly type C. Enzymatic activity of SMase increased linearly with time and is pH dependent with two peaks by pH 5.5 and pH 7.5. The addition of manganese to the reaction mixture increased the SMase activity by 1.97.


Asunto(s)
Esfingomielina Fosfodiesterasa/biosíntesis , Tricomoniasis/enzimología , Trichomonas vaginalis/enzimología , Apoptosis/genética , Ceramidas/química , Femenino , Humanos , Concentración de Iones de Hidrógeno , Hidrólisis , Fosforilcolina/química , Transducción de Señal , Esfingomielina Fosfodiesterasa/aislamiento & purificación , Esfingomielinas/química , Tricomoniasis/genética , Tricomoniasis/parasitología , Trichomonas vaginalis/patogenicidad
5.
Artículo en Inglés | MEDLINE | ID: mdl-22966243

RESUMEN

Rubus liebmannii is an endemic species from Mexico used in traditional medicine primarily to treat dysentery and cough. The in vitro activity against Giardia lamblia and Entamoeba histolytica that produces the ethanolic extract of the aerial parts of the plant led us to expand the pharmacological and phytochemical research of this species. Gastrointestinal disorders including amebiasis remain one of the health problems that need to be addressed and it is of interest to find alternatives that improve their treatment. Also, it is important to emphasize that R. liebmannii grows wild in the country and is not found in abundance; therefore, alternatives that avoid overexploitation of the natural resource are mandatory. Ongoing with the evaluation of the potentialities that R. liebmannii possesses for treating infectious gastrointestinal diseases, the aim of the present study was to evaluate the biological effects and the chemical composition of the micropropagated plant.

6.
Artículo en Inglés | MEDLINE | ID: mdl-21584254

RESUMEN

The efficacy of decoction in extracting mycobactericidal compounds from Flourensia cernua (Hojasé) leaves and fractionation with solvents having ascending polarity was compared with that of (i) ethanol extraction by still maceration, extraction with a Soxhlet device, shake-assisted maceration, or ultrasound-assisted maceration, followed by fractionation with n-hexane, ethyl acetate, and n-butanol; (ii) sequential extraction with n-hexane, ethyl acetate, and n-butanol, by still maceration, using a Soxhlet device, shake-assisted maceration, or ultrasound-assisted maceration. The in vitro mycobactericidal activity of each preparation was measured against drug-sensitive (SMtb) and drug-resistant (RMtb) Mycobacterium tuberculosis strains. The results of which were expressed as absolute mycobactericidal activity (AMA). These data were normalized to the ΣAMA of the decoction fraction set. Although decoction was inactive, the anti-RMtb normalized ΣAMA (NAMA) of its fractions was comparable with the anti-RMtb NAMA of the still maceration extracts and significantly higher than the anti-SMtb and anti-RMtb NAMAs of every other ethanol extract and serial extract and fraction. Hexane extracted, from decoction, material having 55.17% and 92.62% of antituberculosis activity against SMtb and RMtb, respectively. Although the mycobactericidal activity of decoction is undetectable; its efficacy in extracting F. cernua active metabolites against M. tuberculosis is substantially greater than almost all pharmacognostic methods.

7.
Exp Parasitol ; 127(1): 80-3, 2011 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-20603119

RESUMEN

The influence of low-frequency electromagnetic (LF-EM) waves on microorganisms has been a subject of experimental investigations for more than two decades and the results are promising. In parallel, an interesting procedure known as biophysical-information-therapy or bioresonance therapy (BRT) which in principle is based on LF-EM stimulation, has emerged. BRT was discovered in the late 1980's but it is still poorly studied. This paper demonstrates that by transferring metronidazole information to water samples by an electronic amplifier (BRT device), the growth of axenically cultured trophozoites of Entamoeba histolytica and Trichomonasvaginalis is significantly inhibited, compared with those cultures treated with non and sham electro-transferred water samples. A positive control of metronidazole, a well-known cytotoxic drug against parasites, was used as a reference.


Asunto(s)
Antiprotozoarios/farmacología , Entamoeba histolytica/crecimiento & desarrollo , Metronidazol/farmacología , Fármacos Sensibilizantes a Radiaciones/farmacología , Trichomonas vaginalis/crecimiento & desarrollo , Agua/química , Bioensayo , Entamoeba histolytica/efectos de los fármacos , Entamoeba histolytica/efectos de la radiación , Radiación , Trichomonas vaginalis/efectos de los fármacos , Trichomonas vaginalis/efectos de la radiación , Agua/farmacología
8.
Exp Parasitol ; 125(4): 394-9, 2010 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-20350542

RESUMEN

Sphingomyelinase (SMase) activity was measured in Entamoeba histolytica particulate and soluble subcellular fractions. The effects on SMase of incubation time, total protein concentration, pH, and several divalent cations were determined. SMase-C and other unidentified esterase activity were detected in soluble and particulate fractions. SMase-C was 94.5-96.0% higher than the unidentified esterase activity. Soluble and insoluble SMase-C specific activities increased with protein dose and incubation time. Soluble and insoluble SMase-C activities were maximum at pH 7.5 and were dependent on Mg(2+), Mn(2+), or Co(2+), and inhibited by Zn(2+), Hg(2+), Ca(2+), and EDTA. SMase-C was active in the pH range of 3-10 and its maximum activity was at pH 7.5. The soluble and insoluble SMases have remarkably similar physicochemical properties, strongly suggesting that E. histolytica has just one isoform of neutral SMase-C that had not been described before and might be essential for E. histolytica metabolism or virulence.


Asunto(s)
Entamoeba histolytica/enzimología , Esterasas/metabolismo , Esfingomielina Fosfodiesterasa/metabolismo , Animales , Calcio/farmacología , Cobalto/farmacología , Cricetinae , Relación Dosis-Respuesta a Droga , Entamoeba histolytica/patogenicidad , Concentración de Iones de Hidrógeno , Magnesio/farmacología , Masculino , Manganeso/farmacología , Mercurio/farmacología , Mesocricetus , Proteínas Protozoarias/metabolismo , Esfingomielina Fosfodiesterasa/efectos de los fármacos , Factores de Tiempo , Virulencia , Zinc/farmacología
9.
Exp Parasitol ; 119(2): 202-6, 2008 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-18396281

RESUMEN

Exposure to extremely low-frequency (ELF) electromagnetic fields appears to result in a number of important biological changes. In the present study, we evaluated the effects of 60 Hz sinusoidal magnetic fields (MF) at magnetic flux densities of 1.0, 1.5 and 2.0 mT on growth and differentiation of the protozoan Entamoeba invadens. We demonstrated an inhibitory growth effect when trophozoite cultures were exposed to 1.5 and 2.0 mT. Furthermore, we found that there was not a synergistic effect in cultures co-exposed to MF and Metronidazole, a cytotoxic drug against amoebic cells. In addition, MF exposure inhibited the encystation process of E. invadens.


Asunto(s)
Campos Electromagnéticos , Entamoeba/crecimiento & desarrollo , Entamoeba/efectos de la radiación , Animales , Antiprotozoarios/farmacología , Relación Dosis-Respuesta en la Radiación , Entamoeba/efectos de los fármacos , Entamoeba/fisiología , Dosificación Letal Mediana , Metronidazol/farmacología , Distribución Aleatoria
10.
Arch Med Res ; 37(1): 45-9, 2006 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-16314185

RESUMEN

BACKGROUND: Tuberculosis is a chronic disease caused mainly by Mycobacterium tuberculosis. The emergence of antibiotic-resistant strains of this species underscores the need for novel effective drugs against resistant mycobacteria as first-line antituberculosis medications. METHODS: Crude aqueous (obtained by decoction, in accordance with the traditional mode of preparation), methanol, acetone, and hexane extracts from aerial parts of Artemisia ludoviciana Nutt., Chenopodium ambrosioides L., Marrubium vulgare L., Mentha spicata L., and Flourensia cernua DC were assessed for their ability to either inhibit the growth of or kill M. tuberculosis strains H37Rv and CIBIN:UMF:15:99, the former being sensitive to, and the latter resistant to, streptomycin, isoniazide, rifampin, ethambutol, and pyrazinamide. These five plant species are used in Mexico to treat respiratory disorders. RESULTS: Flourensia cernua was the uniquely active plant among those evaluated. Its hexane and acetone extracts not only inhibited the growth of but killed M. tuberculosis. The hexane extract showed a minimal inhibitory concentration (MIC) of 50 and 25 microg/mL against sensitive and resistant strains, respectively; the acetone extract was active against only CIBIN:UMF:15:99 (MIC = 100 microg/mL). CONCLUSIONS: The hexane extract from F. cernua leaves could be an important source of bactericidal compounds against multidrug-resistant M. tuberculosis.


Asunto(s)
Antibacterianos/farmacología , Asteraceae/química , Farmacorresistencia Bacteriana Múltiple/efectos de los fármacos , Mycobacterium tuberculosis/crecimiento & desarrollo , Componentes Aéreos de las Plantas/química , Extractos Vegetales/farmacología , Acetona/química , Antibacterianos/química , Antibacterianos/uso terapéutico , Enfermedad Crónica , Hexanos/química , Pruebas de Sensibilidad Microbiana , Extractos Vegetales/química , Extractos Vegetales/uso terapéutico , Tuberculosis Resistente a Múltiples Medicamentos/tratamiento farmacológico
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