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1.
New Delhi; World Health Organization. Regional Office for South-East Asia; 2018. , 8, 2
en Inglés | WHO IRIS | ID: who-274579

RESUMEN

The Asia Pacific Observatory on Health Systems and Policies (the APO) is a collaborative partnership of interested governments, international agencies, foundations, and researchers that promotes evidence-informed health systems policy regionally and in all countries in the Asia Pacific region. The APO collaboratively identifies priority health system issues across the Asia Pacific region; develops and synthesizes relevant research to support and inform countries' evidence-based policy development; and builds country and regional health systems research and evidence-informed policy capacity.


Asunto(s)
Sector de Atención de Salud , Planes de Sistemas de Salud
5.
Chem Pharm Bull (Tokyo) ; 45(5): 842-8, 1997 May.
Artículo en Inglés | MEDLINE | ID: mdl-9178521

RESUMEN

Cyproheptadine is a drug that shows high affinity for type 2 (5-HT2) receptors. We studied a series of compounds obtained by modification of the tricyclic system of Cyp (dibenzocycloheptadiene): 2f (thioxanthene), 2g (xanthene), 2h (dihydrodibenzocycloheptadiene), 2j (diphenyl), 2i (fluorene), and 3b (phenylmethyl). Their activities at the rat cerebral cortex 5-HT2A receptor were (pKi +/- S.E.M.): 8.80 +/- 0.11 (Cyp), 8.60 +/- 0.07 (2f), 8.40 +/- 0.02 (2g), 8.05 +/- 0.03 (2h), 7.87 +/- 0.12 (2j), 6.70 +/- 0.02 (2i) and 6.45 +/- 0.02 (3b); those at the rat stomach fundus 5-HT2B receptor (pA2 +/- S.E.M.) were: 9.14 +/- 0.25 (Cyp), 8.49 +/- 0.07 (2f), 7.58 +/- 0.58 (2g), 7.02 +/- 0.14 (2h), 6.07 +/- 0.20 (2j), and undetectable (2i, 3b): and those at the pig choroidal plexus 5-HT2C receptor (pKi +/- S.E.M.) were: 8.71 +/- 0.08 (Cyp), 8.68 +/- 0.01 (2f), 8.58 +/- 0.20 (2g), 7.95 +/- 0.05 (2h), 7.57 +/- 0.04 (2j), 6.98 +/- 0.04 (2i) and 6.63 +/- 0.20 (3b). The slopes did not differ significantly from unity. The compounds exhibited the same order of activities at every type of receptor, and the most active molecules presented certain steric (butterfly conformation of the tricyclic system) and electrostatic (proton affinity on the top of the central rings) patterns. It is concluded that the activity of cyproheptadine derivatives at 5-HT2 receptors is related to these molecular features, which make feasible a common disposition to interact with all three 5-HT2 subtypes.


Asunto(s)
Ciproheptadina/análogos & derivados , Ciproheptadina/síntesis química , Receptores de Serotonina/efectos de los fármacos , Antagonistas de la Serotonina/síntesis química , Animales , Unión Competitiva/efectos de los fármacos , Corteza Cerebral/metabolismo , Plexo Coroideo/efectos de los fármacos , Plexo Coroideo/metabolismo , Ciproheptadina/farmacología , Ergolinas/metabolismo , Fundus Gástrico/efectos de los fármacos , Técnicas In Vitro , Ketanserina/metabolismo , Cinética , Masculino , Modelos Moleculares , Ratas , Ratas Sprague-Dawley , Antagonistas de la Serotonina/química , Antagonistas de la Serotonina/farmacología , Relación Estructura-Actividad , Porcinos
6.
Protein Sci ; 6(5): 1024-30, 1997 May.
Artículo en Inglés | MEDLINE | ID: mdl-9144773

RESUMEN

The formulation of HIV-1 PR inhibitors as anti-viral drugs has been hindered by the appearance of protease strains that present drug resistance to these compounds. The mechanism by which the HIV-1 PR mutants lower their affinity for the inhibitor is not yet fully understood. We have applied a modified Poisson-Boltzmann method to the evaluation of the molecular interactions that contribute to the lowering of the inhibitor affinity to some polar mutants at position 82. These strains present drug resistance behavior and hence are ideally suited for these studies. Our results indicate that the reduction in binding affinity is due to the solvation effects that penalize the binding to the more polar mutants. The inhibitor binding ranking of the different mutants can be explained from the analysis of the different components of our free energy scoring function.


Asunto(s)
Inhibidores de la Proteasa del VIH/química , Inhibidores de la Proteasa del VIH/metabolismo , Proteasa del VIH/química , Proteasa del VIH/metabolismo , Arginina , Sitios de Unión , Ácido Glutámico , VIH-1/enzimología , Cinética , Mutagénesis Sitio-Dirigida , Mutación Puntual , Proteínas Recombinantes/química , Proteínas Recombinantes/metabolismo , Soluciones , Termodinámica
7.
Protein Sci ; 4(7): 1356-64, 1995 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-7670378

RESUMEN

We have developed a simple approach for the evaluation of the free energies of inhibitor binding to the protease of the human immunodeficiency virus (HIV-1 PR). Our algorithm is based on the observation that most groups that line the binding pockets of this enzyme are hydrophobic in nature. Based on this fact, we have likened the binding of an inhibitor to this enzyme to its transfer from water to a medium of lower polarity. The resulting expression produced values for the free energy of binding of inhibitors to the HIV-1 PR that are in good agreement with experimental values. The additive nature of this approach has enabled us to partition the free energy of binding into the contributions of single fragments. The resulting analysis clearly indicates the existence of a ranking in the participation of the enzyme's subsites in binding. Although all the enzyme's pockets contribute to binding, the ones that bind the P2-P'2 span of the inhibitor are in general the most critical for high inhibitor potency. Moreover, our method has allowed us to determine the nature of the functional groups that fit into given enzyme binding pockets. Perusal of the energy contributions of single side chains has shown that a large number of hydrophobic and aromatic groups located in the central portion of the HIV-1 PR inhibitors present optimal binding. All of these observations are in agreement with experimental evidence, providing a validation for the physical relevancy of our model.


Asunto(s)
Inhibidores de la Proteasa del VIH/metabolismo , Proteasa del VIH/metabolismo , Solventes , Sitios de Unión , Proteasa del VIH/química , Estructura Molecular , Termodinámica
8.
Planta Med ; 59(1): 26-7, 1993 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-8441777

RESUMEN

Kaempferol 3-O-[alpha-L-rhamnopyranosyl (1-->6)-beta-D-glucopyranoside] and kaempferol 3-O-[beta-D-glucopyranoside] were isolated from the leaves of Hedyosmum bonplandianum H.B.K. (Chloranthaceae), which is used in Colombian folk medicine as an analgesic. The n-butanol extract and the glycosyl flavonoids isolated exhibited significant analgesic activity in mice.


Asunto(s)
Analgésicos/farmacología , Flavonoides/farmacología , Glicósidos/farmacología , Plantas Medicinales/química , Analgésicos/química , Analgésicos/aislamiento & purificación , Animales , Secuencia de Carbohidratos , Flavonoides/química , Flavonoides/aislamiento & purificación , Glicósidos/química , Glicósidos/aislamiento & purificación , Masculino , Ratones , Datos de Secuencia Molecular , Estructura Molecular , Ratas , Ratas Wistar
9.
Planta Med ; 56(1): 89-91, 1990 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-17221375

RESUMEN

Eight lignans (+/-)-syringaresinol, (-)-pinoresinol, (+)-sesamin, (+)-eudesmin, (+)-epieudesmin, (-)-asarinin, (-)-matairesinol, (-)-kobusin, two terpenes lupeol, beta-sitosterol, one aliphatic unsaturated amide, hydroxy-gamma-sanshoöl, and one alkaloid, magnoflorine, were isolated from ZANTHOXYLUM species of Central and South America. Their structures were elucidated mainly by (1)H-, (13)C-NMR, and mass spectroscopy.

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