Artículos Científicos

URI permanente para esta colecciónhttp://10.0.96.45:4000/handle/11056/14690

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Anxiolytic activity and active principles of Piper amalago (Piperaceae), a medicinal plant used by the Q’eqchi’ Maya to treat susto, a culture-bound illness
(Elsevier, 2016-06-05) Mullally, M.; Cayer, C.; Muhammad, A.; Walshe-Roussel, B.; Ahmed, F.; Sanchez-Vindas, PE.; Otárola Rojas, Marco Antonio; Merali, Zul; Cal, V.; Durst, Tony; Trudeau, Vance; Arnason, John
Ethnopharmacological relevance The medicinal plant, Piper amalago L. (Piperaceae), is used traditionally by Q'eqchi' Maya healers for the treatment of "susto" a culture-bound syndrome. Previous research suggests that susto symptoms may be a manifestation of anxiety. The objectives were to characterize the effect of ethanolic extract of P. amalago in behavioral assays of anxiety at doses representative of traditional use and to isolate active principles. Materials and methods Rats treated orally with low dose ethanolic extracts of P. amalago leaves (8-75 mg/kg) were tested in several behavioral paradigms including the elevated plus maze (EPM), social interaction (SI), and conditioned emotional response (CER) tests, and compared to diazepam, a positive control. The active anxiolytic principle was isolated by bioassay guided isolation using an in vitro GABAA competitive binding assay. Results Extracts had significant anxiolytic activity in all behavioral tests, with the strongest activity in the SI and the CER paradigms. In an in vitro GABAA competitive binding assay, a 66.5 μg/mL concentration of P. amalago ethanol extract displaced 50% of the GABAA-BZD receptor ligand [3H]-Flunitrazepam. Bioassay-guided fractionation identified a furofuran lignan, a molecule with structural similarity to yangambin, with high affinity for the GABAA-BZD receptor as the principle bioactive. Conclusion The results suggest that the ethnobotanical use of this plant may have a pharmacological basis in its anxiolytic activity, as demonstrated in animal behaviour tests.
Checklist of the vascular flora of Reserva Biológica San Luis, Costa Rica
(Pensoft, 2016-03-21) Jiménez-Alfaro, Esteban José; Juárez, Pedro; Díaz, Armando
The Reserva Biológica San Luis is a small protected area located on the Pacific side of the Cordillera de Tilarán, northwestern Costa Rica, with a forest transitioning between the basal and premontane floras according to Holdridge’s Life Zones. An inventory of the vascular flora of the reserve was performed by collecting botanical samples during three years and consulting the databases of the CR, INB, MO and USJ herbaria. We report 130 families, 477 genera and 716 species of native vascular plants. Angiosperms comprise the largest group with 94.3%, followed by Pteridophytes 5.4% and Lycophytes 0.3%. The best represented life forms are herbaceous and arborescent with 35.7% and 26.8% respectively. Fabaceae and Piper are the most diverse family and genus, with 67 and 15 species respectively. Despite occupying 0.000049% of the total area of Costa Rica, this reserve protects approximately 7.3% of the vascular plants of the country.
Chemical composition of PM 2.5 particles in Salamanca, Guanajuato Mexico: Source apportionment with receptor models
(Science Direct, 2012-04) Herrera-Murillo, Jorge; Campos Ramos, Arturo; Ángeles García, Felipe; Blanco Jiménez, Salvador; Cárdenas, Beatriz; Mizohata, Akira
The National Institute of Ecology, through Management General for Environmental Research and Training (DGCENICA) carried out a sampling campaign where a total of 21 elements were determined in 140PM 2.5 samples from one sampling site located in the city of Salamanca, Guanajuato-Mexico between November 2006 and November 2007. The annual average PM 2.5 concentration was 45μg/m 3 almost three times the Mexican Annual standard for PM 2.5. Mineral, organic and elemental carbon were the most important components present in particles PM 2.5. Two advanced receptor models, UNMIX and positive matrix factorization (PMF) were used for PM 2.5 source identification. Four and six sources were identified by UNMIX and PMF, respectively, from a combined dataset including 15 chemical species. Source categories were determined based on both, component abundances in the source profiles, and their temporal characteristics. Overall, different sources were identified as the major contributors: heavy fuels combustion, traditional brick production-agricultural burning, crustal, road traffic and secondary organic aerosols.
Mormodes salazarii (Orchidaceae, Catasetinae), a new species with greenish-white flowers from Costa Rica
(Phytotaxa, 2016-01-25) Blanco, Mario; Jiménez-Alfaro, Esteban José; Juárez, Pedro
Mormodes salazarii (Orchidaceae, Catasetinae), a new species apparently endemic to Costa Rica, is described and illustrated. It is similar to M. fractiflexa because of its non-resupinate flowers, entire lip and revolute margins of sepals and petals, but differs from that species by its erect flowers (vs. pendulous) and strongly reflexed lateral sepals without colored lines (vs. widely open or slightly reflexed lateral sepals with red blurred lines)
Polycyclic aromatic hydrocarbons in filterable PM2.5 emissions generated from regulated stationary sources in the metropolitan area of Costa Rica
(Elsevier, 2017-09) Herrera-Murillo, Jorge; Rojas Marín, José Félix; Mugica-Alvarez, Violeta; Solórzano Arias, David; Beita Guerrero, Víctor Hugo
This study analyzed the profiles of polycyclic aromatic hydrocarbons (PAHs) in filterable PM2.5 particles collected from a total of 71 boilers and 22 indirect type furnaces that burn liquid and biomass fuels in the Metropolitan Area of Costa Rica, from February 2014 to November 2015. Modified method NIOSH 5506 was used to analyze PAHs content present in the filter samples. The average concentration of PM2.5 showed values between 18 and 735 mg m−3, based on the source and fuel type used, while the total PAHs in the PM2.5 fraction ranged 1.02–592 μgm−3. For biomass boilers, the most abundant species were Benzo[g,h,i]perylene (BghiP) (35.7–46.5%), Indeno[1,2,3-cd]pyrene (IND) (20.6–27.1%), Benzo[a]pyrene (BaP) (5.2–14.7%) and Dibenzo[a,h]anthracene (DBA) (3.2–13.9%), while for liquid fuels IND (12.8–20.5%), BghiP (7.9–21.2%), Fluoranthene (Flu) (14.5–21.3%) and Pyrene (Pyr) (9.8–14.5%) prevailed. The particles from biomass furnace emissions present higher concentrations of PAHs classified by the U.S. EPA as probable human carcinogens causing a greater health risk than other fuels. Among the diagnostic concentration ratios examined, only BaP/(BaP+Chr), BaA/Chr, BaA/BaP and Pyr/BaP coefficients demonstrated codependency on the type of fuel used.

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