Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 10 de 10
Filtrar
Mais filtros

Tipo de documento
Intervalo de ano de publicação
1.
Pharm Biol ; 54(4): 569-71, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26471095

RESUMO

CONTEXT: More analgesic compounds are needed in medicine against pain since the available drugs displayed secondary effects. Natural products are a source of molecules to develop new analgesics, using the information of plants, applied against pain, with effects such as pungency, tingling, and needle, due to their possible role in the central nervous system (NCS). Citrus reticulata Blanco (Rutaceae) leaves are usually bitten to flavor the mouth and possess this type effect in lips and tongues; due to this fact the structure of the bioctive compound could be the source of other types of analgesics. OBJECTIVE: The objective of this study is to determine the causal agent of the pungent effect in mandarin essential oil. MATERIALS AND METHODS: Mandarin essential oil was obtained and then purified by column chromatography. Each fraction was tested and pungency was detected only in the first fraction which was pure. RESULTS: The compound responsible for the pungency in the essential oils of leaves from Citrus reticulata (mandarin) was purified and the structure was assigned as methyl-N-methylanthranilate, on the basis of NMR 1D and 2D and MS. This substance corresponds to another type of molecule involving an antinociceptive effect. CONCLUSIONS: Terpenes are compounds found in essential oils. The compound responsible for the pungency of mandarin and other citrus leaves was isolated, and surprisingly it was identified as a methyl-N-methylanthranilate. This kind of molecules with this activity could be used to discover new analgesics in human therapy against pain.


Assuntos
Citrus , Óleos Voláteis/química , Óleos Voláteis/isolamento & purificação , Folhas de Planta/química , ortoaminobenzoatos/química , ortoaminobenzoatos/isolamento & purificação
2.
Plant Physiol ; 157(1): 372-85, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21788363

RESUMO

We investigated responses of growth, leaf gas exchange, carbon-isotope discrimination, and whole-plant water-use efficiency (W(P)) to elevated CO(2) concentration ([CO(2)]) in seedlings of five leguminous and five nonleguminous tropical tree species. Plants were grown at CO(2) partial pressures of 40 and 70 Pa. As a group, legumes did not differ from nonlegumes in growth response to elevated [CO(2)]. The mean ratio of final plant dry mass at elevated to ambient [CO(2)] (M(E)/M(A)) was 1.32 and 1.24 for legumes and nonlegumes, respectively. However, there was large variation in M(E)/M(A) among legume species (0.92-2.35), whereas nonlegumes varied much less (1.21-1.29). Variation among legume species in M(E)/M(A) was closely correlated with their capacity for nodule formation, as expressed by nodule mass ratio, the dry mass of nodules for a given plant dry mass. W(P) increased markedly in response to elevated [CO(2)] in all species. The ratio of intercellular to ambient CO(2) partial pressures during photosynthesis remained approximately constant at ambient and elevated [CO(2)], as did carbon isotope discrimination, suggesting that W(P) should increase proportionally for a given increase in atmospheric [CO(2)]. These results suggest that tree legumes with a strong capacity for nodule formation could have a competitive advantage in tropical forests as atmospheric [CO(2)] rises and that the water-use efficiency of tropical tree species will increase under elevated [CO(2)].


Assuntos
Dióxido de Carbono/metabolismo , Fabaceae/fisiologia , Árvores/fisiologia , Fabaceae/crescimento & desenvolvimento , Fabaceae/metabolismo , Nitrogênio/metabolismo , Fixação de Nitrogênio , Árvores/crescimento & desenvolvimento , Árvores/metabolismo
3.
New Phytol ; 190(3): 724-39, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21294735

RESUMO

• Paleobotanists have long used models based on leaf size and shape to reconstruct paleoclimate. However, most models incorporate a single variable or use traits that are not physiologically or functionally linked to climate, limiting their predictive power. Further, they often underestimate paleotemperature relative to other proxies. • Here we quantify leaf-climate correlations from 92 globally distributed, climatically diverse sites, and explore potential confounding factors. Multiple linear regression models for mean annual temperature (MAT) and mean annual precipitation (MAP) are developed and applied to nine well-studied fossil floras. • We find that leaves in cold climates typically have larger, more numerous teeth, and are more highly dissected. Leaf habit (deciduous vs evergreen), local water availability, and phylogenetic history all affect these relationships. Leaves in wet climates are larger and have fewer, smaller teeth. Our multivariate MAT and MAP models offer moderate improvements in precision over univariate approaches (± 4.0 vs 4.8°C for MAT) and strong improvements in accuracy. For example, our provisional MAT estimates for most North American fossil floras are considerably warmer and in better agreement with independent paleoclimate evidence. • Our study demonstrates that the inclusion of additional leaf traits that are functionally linked to climate improves paleoclimate reconstructions. This work also illustrates the need for better understanding of the impact of phylogeny and leaf habit on leaf-climate relationships.


Assuntos
Clima , Internacionalidade , Paleontologia , Folhas de Planta/anatomia & histologia , Calibragem , Fósseis , Geografia , Modelos Biológicos , Tamanho do Órgão , Filogenia , Chuva , Análise de Regressão , Especificidade da Espécie , Temperatura
4.
Bioorg Med Chem ; 18(9): 3299-306, 2010 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-20381363

RESUMO

A series of natural and synthetic piperine amides were evaluated for activity on the human TRPV1 expressed in HEK293 cells. The agonistic effect of piperine amides was mainly dependent on the length of the carbon chain. Structural changes of double bonds and stereochemistry in the aliphatic chain of these compounds did not change their potency or efficacy, indicating that increased rigidity or planarity of the piperine structure does not affect the activity. The opening of the methylenedioxy ring or changes in the heterocyclic ring of the piperine molecule reduced or abolished activity. Furthermore, inactive compounds did not display functional antagonistic activity.


Assuntos
Alcaloides/farmacologia , Amidas/farmacologia , Benzodioxóis/farmacologia , Piperidinas/farmacologia , Alcamidas Poli-Insaturadas/farmacologia , Canais de Cátion TRPV/metabolismo , Alcaloides/síntese química , Alcaloides/química , Amidas/síntese química , Amidas/química , Benzodioxóis/síntese química , Benzodioxóis/química , Capsaicina/análogos & derivados , Capsaicina/farmacologia , Linhagem Celular , Relação Dose-Resposta a Droga , Humanos , Estrutura Molecular , Piperidinas/síntese química , Piperidinas/química , Alcamidas Poli-Insaturadas/síntese química , Alcamidas Poli-Insaturadas/química , Espectrometria de Fluorescência , Canais de Cátion TRPV/agonistas , Canais de Cátion TRPV/antagonistas & inibidores
5.
Front Pharmacol ; 11: 584668, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33424593

RESUMO

Through bioguided in vitro assays, the leishmanicidal and trypanocidal effects of an ethanol extract, seven fractions, and two pure substances obtained from Clathrotropis brunnea Amshoff sawdust were established. The effectiveness of the two metabolites was confirmed in a hamster model of cutaneous Leishmaniasis by Leishmania braziliensis and in Balb/c mice infected by Trypanosoma cruzi. In vitro, 3,5-dimethoxystilbene was the most active against L. braziliensis amastigotes, with a median lethal concentration (LC50) of 4.18 µg/ml (17.40 µM) and a selectivity index of 3.55, but showed moderate activity for T. cruzi, with a median effective concentration (EC50) value of 27.7 µg/ml (115.36 µM). Flavanone pinostrobin, meanwhile, showed high activity against L. braziliensis, with an EC50 of 13.61 µg/ml (50.39 µM), as well as for T. cruzi, with an EC50 of 18.2 µg/ml (67.38 µM). The animal model assay of cutaneous Leishmaniasis showed that 50% of the hamsters treated with pinostrobin were definitively cured the cutaneous ulcer, and 40% showed an improvement, with a reduction in the size of the of 84-87%. Moreover, Balb/c mice experimentally infected with T. cruzi and treated for 25 days with pinostrobin experienced a reduction in their parasitemia by 71%. These results demonstrate the high potential of C. brunnea Amshoff against cutaneous Leishmaniasis and American trypanosomiasis and indicate the pharmacological potential of waste from the wood industry, which has tons of potentially useful chemicals for the development of new medicines.

6.
Rev. colomb. cienc. pecu ; 34(3): 224-230, July-Sept. 2021. graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1408023

RESUMO

Abstract Background: Bovine tuberculosis (BTB) and brucellosis are associated with devastating losses in the livestock sector in Colombia and even in developed countries. Real-time disease surveillance is a key strategy to control and eradicate infectious disease outbreaks. Objective: To design an epidemiological tool for monitoring BTB and brucellosis in Colombia. Methods: An interactive platform for disease mapping of BTB and brucellosis during an observation period between years 2004 and 2019 was designed. Results: Our analysis showed that the provinces of Cundinamarca and Valle del Cauca are regions affected by BTB and brucellosis epidemics, respectively (p<0.001). Furthermore, increased case detection of BTB was reported in 2012 and brucellosis in 2019 (p<0.001). Conclusions: This epidemiological platform allows tracking BTB and tuberculosis hotspots, identifying trends over time, and provides useful information to animal health authorities for designing new strategies in control programs.


Resumen Antecedentes: La tuberculosis bovina (TBB) y la brucelosis están asociadas con problemas persistentes en la ganadería Colombiana e incluso en los países desarrollados. La vigilancia de enfermedades en tiempo real es una estrategia clave para controlar y erradicar brotes de enfermedades infecciosas. Objetivo: Diseñar una herramienta epidemiológica para monitorear TBB y brucelosis en Colombia. Métodos: Se diseñó un panel de control interactivo para el mapeo de ambas enfermedades durante el periodo de observación entre los años 2004 y 2019. Resultados: El análisis de la herramienta mostró que las Provincias de Cundinamarca y Valle del Cauca han sido áreas epidémicas para TBB y brucelosis, respectivamente (p<0,001). Además, se encontró un aumento de la detección de casos de TBB en 2012 y de brucelosis durante 2019 (p<0,001). Conclusiones: Este panel epidemiológico permite el seguimiento de puntos críticos de TBB y tuberculosis, identificando sus tendencias a lo largo del tiempo, y proporciona información útil para las autoridades de sanidad animal que diseñan nuevas estrategias para los programas de control.


Resumo Antecedentes: A tuberculose bovina (TBB) e a brucelose estão associadas a problemas persistentes no campo da pecuária na Colômbia e até em países desenvolvidos. Portanto, a vigilância de doenças em tempo real é uma estratégia essencial para controlar e erradicar surtos de doenças infecciosas. Objetivo: Projetar uma ferramenta epidemiológica para monitorar a TB e a brucelose na Colômbia. Métodos: Um painel de controle interativo foi projetado para o mapeamento de ambas as doenças entre 2004 e 2019 como período de observação. Resultados: A análise da ferramenta mostrou que as Províncias de Cundinamarca e Valle del Cauca foram áreas epidêmicas para TBB e brucelose, respectivamente (p<0,001). Além disso, foi encontrado um aumento na detecção de casos em 2012 para TBB e brucelose durante 2019 (p<0,001). Conclusões: Esse painel epidemiológico poderia permitir o monitoramento de pontos críticos dessas doenças, identificando tendências ao longo do tempo, fornecendo informações úteis para as autoridades de saúde animal que elaboram novas estratégias para programas de controle.

7.
Phytochemistry ; 72(2-3): 238-41, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21211807

RESUMO

Prenylhydroxybenzoic acid derivatives and other two analogues previously reported were isolated from Piper arieianum leaves. The structures of the compounds were assigned from detailed spectroscopical analysis (NMR 1D and 2D and HR ESI TOF MS) data and by comparison with data from the literature. These molecules posses pungent activity different to that of capsaicin and their activity is related to their structure and their mechanism of action can involve interactions with TRPV1 channel.


Assuntos
Hidroxibenzoatos/isolamento & purificação , Hidroxibenzoatos/farmacologia , Piper/química , Benzoatos , Hidroxibenzoatos/química , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular , Folhas de Planta/química , Prenilação
8.
Am J Bot ; 97(1): 71-9, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21622368

RESUMO

Although Rhamnaceae are distributed worldwide today, the former hypothesis for its Laurasian origins may need to be reconsidered in view of recently discovered fossils from the Guaduas Formation of central Colombia (∼68 Ma), including fossil leaves (Berhamniphyllum) and a fruit (Archaeopaliurus boyacensis). Recent phylogenetic studies calibrate the stem of Rhamnaceae at 64 Ma and divide the family into three groups, rhamnoid, ampeloziziphoid, and ziziphoid. Although the fruit, Archaeopaliurus boyacensis, resembles that of Paliurus and suggests a relationship to the Paliureae in the ziziphoid group, associated leaves of Berhamniphyllum conform in architecture to those found today only in the Rhamneae tribe. The Maastrichtian age of these fossils predates the ages previously estimated for the Rhamneae tribe (28.5 Ma) and the Paliureae tribe (31.6 Ma) using a modified clock approach. Based on the new megafossil evidence, two alternative ideas are proposed: (1) that these fossils predate the extant tribes or (2) that the family diversified into modern tribes earlier than previously proposed.

9.
Bol. latinoam. Caribe plantas med. aromát ; 13(4): 311-323, jul. 2014. ilus, tab
Artigo em Inglês | LILACS | ID: lil-785449

RESUMO

Leishmaniasis and trypanosomiasis are parasitic diseases with a high infection rate, being a serious public health issue in the new world. Unfortunately, there are few available commercial drugs, poorly efficient and with increasing parasite resistance. Under these condi- tions, there is a need for new molecules to develop new and better drugs. One approach to carry out this search is using traditional medicine as information source to obtain new molecules or extracts to control these parasite diseases. Sapindus saponaria (Sapindaceae) fruit resin is used in Colombia to treat ulcers caused by Leishmaniasis. In a bioguided study, we have analyzed the in vitro effect of fruit resin, chroma- tographical fractions from fruit resin and also pure compounds against Leishmania species (L. panamensis, L. braziliensis, L. amazonensis and L. donovani) and Trypanosoma cruzi. The in vivo antileishmanial effect was established under the hamster model for cutaneous leish- maniasis by L. panamensis; refined extract of S. saponaria and pure saponins displayed high in vitro and in vivo activity as leishmanicides. In addition, extracts caused low viability on T. cruzi amastigotes. The use of the crude extract can be a good alternative against cutaneous leishmaniasis, due to its activity, reduced hemolytic effect, and easy production procedures.


La Leishmaniasis y la tripanosomiasis son enfermedades parasitarias con una alta incidencia, siendo un serio asunto de salud pública en el nuevo mundo. Desafortunadamente, hay pocas drogas comerciales disponibles, con pobre eficiencia y con una creciente resis- tencia parasitaria. Bajo esas condiciones, se necesitan nuevas moléculas para desarrollar nuevas y mejores drogas. Una aproximación para llevar a cabo esa búsqueda es usar la medicina tradicional como fuente de información para obtener nuevas moléculas o extractos para con- trolar esas enfermedades parasitarias. La resina de Sapindus saponaria (Sapindaceae) se usa en Colombia para tratar úlceras causadas por la Leishmaniasis. En un estudio bioguiado, se analizó el efecto in vitro de varios extractos de la resina, sus fracciones cromatográficas y algu- nos compuestos puros, contra varias especies de Leishmania (L. panamensis, L. braziliensis, L. amazonensis y L. donovani) panamensis y Trypanosoma cruzi. El efecto lesihmanicida in vivo fue establecido usando el modelo en hamster de leishmaniasis cutánea producida por L. panamensis; los extractos refinados de S. saponaria y las saponinas puras mostraron alta actividad in vitro e in vivo como leishmanicidas. Además, los extractos causaron una baja viabilidad en amastigotes de T. cruzi. El uso de extractos refinados en vez de saponinas puras podría ser una buena alternativa contra leishmaniasis cutánea debido a su actividad, poco efecto hemolítico y procedimientos de producción mucho más fáciles.


Assuntos
Extratos Vegetais/farmacologia , Leishmania , Sapindus/química , Tripanossomicidas/farmacologia , Trypanosoma cruzi , Resinas
10.
Phytother Res ; 20(6): 497-9, 2006 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16619346

RESUMO

In the search for antiparasite compounds from the Colombian flora, an active compound against Leishmania (Viannia) panamensis amastigotes was isolated from the fungi Pycnoporus sanguineus. The structural elucid-ation was achieved with spectroscopic methods ((1)H and (13)C NMR and MS). This compound was identified as ergosterol 5,8-endoperoxide.


Assuntos
Antiprotozoários/isolamento & purificação , Ergosterol/análogos & derivados , Leishmania guyanensis , Polyporaceae/química , Animais , Antiprotozoários/química , Ergosterol/química , Ergosterol/isolamento & purificação , Polyporaceae/crescimento & desenvolvimento
SELEÇÃO DE REFERÊNCIAS
Detalhe da pesquisa