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1.
Ann Biomed Eng ; 52(9): 2534-2545, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38836980

RESUMO

Extravehicular activities will play a crucial role in lunar exploration on upcoming Artemis missions and may involve astronauts operating a lunar terrain vehicle (LTV) in a standing posture. This study assessed kinematic response and injury risks using an active muscle human body model (HBM) restrained in an upright posture on the LTV by simulating dynamic acceleration pulses related to lunar surface irregularities. Linear accelerations and rotational displacements of 5 lunar obstacles (3 craters; 2 rocks) over 5 slope inclinations were applied across 25 simulations. All body injury metrics were below NASA's injury tolerance limits, but compressive forces were highest in the lumbar (250-550N lumbar, tolerance: 5300N) and lower extremity (190-700N tibia, tolerance: 1350N) regions. There was a strong association between the magnitudes of body injury metrics and LTV resultant linear acceleration (ρ = 0.70-0.81). There was substantial upper body motion, with maximum forward excursion reaching 375 mm for the head and 260 mm for the chest. Our findings suggest driving a lunar rover in an upright posture for these scenarios is a low severity impact presenting low body injury risks. Injury metrics increased along the load path, from the lower body (highest metrics) to the upper body (lowest metrics). While upper body injury metrics were low, increased body motion could potentially pose a risk of injury from flail and occupant interaction with the surrounding vehicle, suit, and restraint hardware.


Assuntos
Lua , Humanos , Projetos Piloto , Atividade Extraespaçonave , Aceleração , Fenômenos Biomecânicos , Modelos Biológicos , Ferimentos e Lesões/fisiopatologia , Masculino
2.
J Mol Model ; 29(3): 65, 2023 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-36752935

RESUMO

PURPOSE: A recently proposed model potential to study quantum scattering of a positron from a hydrogen molecule is used to solve the Hamilton equations for scattering trajectories. In the present classical description, the positron can transfer energy to the vibrational mode of the molecule, remaining trapped for a while before escaping to infinity. Such vibrational resonances may correspond to trajectories which are embedded in phase-space regions of chaotic scattering.

3.
Traffic Inj Prev ; 23(sup1): S86-S91, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36190765

RESUMO

Objectives: Quantify the independent and combined effects of abdominal muscle quantity and lumbar bone mineral density (BMD) on injury risk and in-hospital outcomes in severely injured motor vehicle crash (MVC) occupants ages 50 and older.Methods: Skeletal muscle area measurements of MVC occupants were obtained through semi-automated segmentation of an axial computed tomography (CT) slice at the L3 vertebra. An occupant height-normalized Skeletal Muscle Index (SMI) was calculated - a defining metric of sarcopenia and low muscle mass (sarcopenia thresholds: <38.5 cm2/m2 females; <52.4 cm2/m2 males). Lumbar BMD was obtained using a validated, phantomless CT calibration method (osteopenia threshold: <145 mg/cm3). SMI and BMD values were used to categorize occupants, and logistic regression was used to associate sarcopenia, osteopenia, and osteosarcopenia predictors to injury outcomes (e.g., Injury Severity Score (ISS), maximum Abbreviated Injury Scale (MAIS) score, fractures) and hospital outcomes (e.g., length of stay, ICU days).Results: Of the 336 occupants, 210 (63%) were female (mean ± SD: age 66.3 ± 10.6). SMI was 41.7 ± 8.0 cm2/m2 in females and 51.2 ± 10.8 cm2/m2 in males. Based on SMI, 40% of females and 55% of males were classified as sarcopenic. BMD was 163.2 ± 38.3 mg/cm3 in females and 164.1 ± 35.4 mg/cm3 in males, with 41% of females and 33% of males classified as osteopenic. Prevalence of both conditions (osteosarcopenia) was similar between females (21%) and males (22%). Incidence of low SMI and BMD increased with age. Sarcopenic individuals were less likely to sustain a MAIS 2+ thorax injury and had longer ICU stays. Osteopenic individuals were more likely to sustain upper extremity injuries and fractures, and were less likely to be discharged to a rehabilitation facility. Osteosarcopenic individuals were less likely to be ventilated or admitted to the ICU but tended to spend more time on the ventilator if placed on one.Conclusions: Osteosarcopenia was not associated with any injury outcomes, but sarcopenia was associated with thoracic injury and osteopenia was associated with upper extremity injury incidence. Sarcopenia was only associated with ICU length of stay, while osteopenia was only associated with discharge destination. Osteosarcopenia was associated with likelihood of being ventilated, being admitted to the ICU, and with increased length of ventilation.


Assuntos
Doenças Ósseas Metabólicas , Fraturas Ósseas , Sarcopenia , Masculino , Humanos , Feminino , Idoso , Pessoa de Meia-Idade , Acidentes de Trânsito , Densidade Óssea , Sarcopenia/diagnóstico por imagem , Sarcopenia/epidemiologia , Fraturas Ósseas/epidemiologia , Doenças Ósseas Metabólicas/epidemiologia , Músculos , Veículos Automotores
4.
J Phys Chem A ; 123(42): 9113-9122, 2019 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-31573199

RESUMO

A full-dimension quasi-classical trajectory study of collisions between two NH radicals is presented. Interatomic interactions are represented by a previously reported global six-dimensional potential energy surface for singlet electronic state of the N2H2 system. This study suggests that the formation of N2 from the collision of two NH radicals may occur via a one-step (NH + NH → N2 + H + H) or two-step (NH + NH → N2H + H → N2 + H + H) microscopic reaction mechanism. A fast vibrational energy redistribution is observed in the four-body complex in the latter mechanism. Excitation functions are presented and discussed. A variant of the vibrational energy quantum mechanical threshold method was used to correct the zero-point energy leakage in the classical calculations. The influence of reactant's rotational and vibrational energy on reactivity was investigated by state-specific calculations with one or both reactants excited. Reaction rate constants for the ground and some rotationally excited states are presented using an Arrhenius-Kooij-like functional form.

5.
Metabolomics ; 15(2): 14, 2019 01 19.
Artigo em Inglês | MEDLINE | ID: mdl-30830463

RESUMO

INTRODUCTION: Comparative analysis of metabolic features of plants has a high potential for determination of quality control of active ingredients, ecological or chemotaxonomic purposes. Specifically, the development of efficient and rapid analytical tools that allow the differentiation among species, subspecies and varieties of plants is a relevant issue. Here we describe a multivariate model based on LC-MS/MS fingerprinting capable of discriminating between subspecies and varieties of the medicinal plant Chamaecrista nictitans, a rare distributed species in Costa Rica. METHODS: Determination of the chemical fingerprint was carried out on a LC-MS (ESI-QTOF) in negative ionization mode, main detected and putatively identified compounds included proanthocyanidin oligomers, several flavonoid C- and O-glycosides, and flavonoid acetates. Principal component analysis (PCA), partial least square-discriminant analysis (PLS-DA) and cluster analysis of chemical profiles were performed. RESULTS: Our method showed a clear discrimination between the subspecies and varieties of Chamaecrista nictitans, separating the samples into four fair differentiated groups: M1 = C. nictitans ssp. patellaria; M2 = C. nictitans ssp. disadena; M3 = C. nictitans ssp. nictitans var. jaliscensis and M4 = C. nictitans ssp. disadena var. pilosa. LC-MS/MS fingerprint data was validated using both morphological characters and DNA barcoding with ITS2 region. The comparison of the morphological characters against the chemical profiles and DNA barcoding shows a 63% coincidence, evidencing the morphological similarity in C. nictitans. On the other hand, genetic data and chemical profiles grouped all samples in a similar pattern, validating the functionality of our metabolomic approach. CONCLUSION: The metabolomic method described in this study allows a reliably differentiation between subspecies and varieties of C. nictitans using a straightforward protocol that lacks extensive purification steps.


Assuntos
Chamaecrista/química , Chamaecrista/metabolismo , Metabolômica/métodos , Cromatografia Líquida de Alta Pressão/métodos , Cromatografia Líquida/métodos , Análise por Conglomerados , Análise Discriminante , Análise Multivariada , Fenóis/química , Análise de Componente Principal/métodos , Espectrometria de Massas por Ionização por Electrospray/métodos , Espectrometria de Massas em Tandem/métodos
6.
Rev. salud pública ; 20(5): 629-636, oct.-nov. 2018. tab, graf
Artigo em Espanhol | LILACS | ID: biblio-1004480

RESUMO

RESUMEN Objetivo Identificar las dimensiones significativas para medir la satisfacción del paciente en centros de urgencia. Asimismo, brindar recomendaciones, basados en la literatura, tanto para proveer un mejor servicio, como para la realización de futuras investigaciones. Método Se realizó una revisión sistemática explorando 5 base de datos: Jstor, Pro-quest, SciELO Public Health, Science Direct Y Redalyc, utilizando como criterios de búsqueda: "Patient Satisfaction", "Quality Of Care", "Satisfaction With Care", "Patients' Perception Of Care", "Emergency Department" y "Emergency Medical Service". Fueron preseleccionados Artículos en inglés y español, de textos completos y publicados entre 1990 y 2015. De 172 artículos, 42 estudios empíricos se incluyeron en el análisis. Resultados El 39% de los artículos fueron de procedencia norteamericana, el 38% europea, el 11% asiática, el 5% sudamericana, el 3% de Oceanía, el 2% africana y el 2% centroamericana. Once dimensiones para medir satisfacción del paciente en centros de urgencia con sus respectivas subvariables fueron identificadas como usadas frecuentemente y estadísticamente significativas. Conclusiones La satisfacción del paciente es una variable multidimensional de la calidad de la atención médica. La comunicación, la atención y cortesía y el tiempo de espera percibido son los principales factores que se deben trabajar para incrementar dicha satisfacción. Variables sociodemográficas como la raza, estado de salud y edad del paciente deben ser valoradas ya que influyen en el nivel de satisfacción. Asimismo, la correlación entre la satisfacción y la intención de retornar al centro a futuro evidencian oportunidades de trabajo para administradores e investigadores en el área de la salud.(AU)


ABSTRACT Objectives To identify the most relevant dimensions for measuring patient satisfaction in urgent care centers. Also, to provide recommendations, based on the literature, both to provide a better service and to conduct further research. Materials and Methods A systematic review was performed in 5 databases: Jstor, Proquest, SciELO Public Health, Science Direct and Redalyc, using as search criteria: "Patient Satisfaction", "Quality Of Care", "Satisfaction With Care", "Patients' Perception Of Care", "Emergency Department" And "Emergency Medical Service". Full-text articles in Spanish and English and published between 1990 and 2015 were pre-selected. Of 172 articles, 42 empirical studies were included in the analysis. Results 39% of the articles were from North America, 38% from Europe, 11% from Asia, 5% from South America, 3% from Oceania and Australia and 2% from Africa and Central America. Eleven dimensions to measure patient satisfaction in urgent care centers with their respective associated variables were identified as frequently used and statistically significant. Conclusions Patient satisfaction is a multidimensional variable of quality healthcare. Communication, customer service, courtesy and waiting times are considered the factors that should be adjusted to increase levels of satisfaction. Sociodemographic variables such as race, health status and age of the patient need to be assessed and studied, since they have effects on the level of satisfaction. Likewise, the correlation between satisfaction and intention to return to the medical center provides opportunities for administrators and investigators of the healthcare area for future work.(AU)


Assuntos
Humanos , Qualidade da Assistência à Saúde/normas , Satisfação do Paciente , Serviços Médicos de Emergência/normas , Pesquisa sobre Serviços de Saúde/normas
7.
Rev Salud Publica (Bogota) ; 20(5): 629-636, 2018.
Artigo em Espanhol | MEDLINE | ID: mdl-33111898

RESUMO

OBJECTIVES: To identify the most relevant dimensions for measuring patient satisfaction in urgent care centers. Also, to provide recommendations, based on the literature, both to provide a better service and to conduct further research. MATERIALS AND METHODS: A systematic review was performed in 5 databases: Jstor, Proquest, SciELO Public Health, Science Direct and Redalyc, using as search criteria: "Patient Satisfaction", "Quality Of Care", "Satisfaction With Care", "Patients' Perception Of Care", "Emergency Department" And "Emergency Medical Service". Full-text articles in Spanish and English and published between 1990 and 2015 were pre-selected. Of 172 articles, 42 empirical studies were included in the analysis. RESULTS: 39% of the articles were from North America, 38% from Europe, 11% from Asia, 5% from South America, 3% from Oceania and Australia and 2% from Africa and Central America. Eleven dimensions to measure patient satisfaction in urgent care centers with their respective associated variables were identified as frequently used and statistically significant. CONCLUSIONS: Patient satisfaction is a multidimensional variable of quality healthcare. Communication, customer service, courtesy and waiting times are considered the factors that should be adjusted to increase levels of satisfaction. Sociodemographic variables such as race, health status and age of the patient need to be assessed and studied, since they have effects on the level of satisfaction. Likewise, the correlation between satisfaction and intention to return to the medical center provides opportunities for administrators and investigators of the healthcare area for future work.


OBJETIVO: Identificar las dimensiones significativas para medir la satisfacción del paciente en centros de urgencia. Asimismo, brindar recomendaciones, basados en la literatura, tanto para proveer un mejor servicio, como para la realización de futuras investigaciones. MÉTODO: Se realizó una revisión sistemática explorando 5 base de datos: Jstor, Pro-quest, SciELO Public Health, Science Direct Y Redalyc, utilizando como criterios de búsqueda: "Patient Satisfaction", "Quality Of Care", "Satisfaction With Care", "Patients' Perception Of Care", "Emergency Department" y "Emergency Medical Service". Fueron preseleccionados Artículos en inglés y español, de textos completos y publicados entre 1990 y 2015. De 172 artículos, 42 estudios empíricos se incluyeron en el análisis. RESULTADOS: El 39% de los artículos fueron de procedencia norteamericana, el 38% europea, el 11% asiática, el 5% sudamericana, el 3% de Oceanía, el 2% africana y el 2% centroamericana. Once dimensiones para medir satisfacción del paciente en centros de urgencia con sus respectivas subvariables fueron identificadas como usadas frecuentemente y estadísticamente significativas. CONCLUSIONES: La satisfacción del paciente es una variable multidimensional de la calidad de la atención médica. La comunicación, la atención y cortesía y el tiempo de espera percibido son los principales factores que se deben trabajar para incrementar dicha satisfacción. Variables sociodemográficas como la raza, estado de salud y edad del paciente deben ser valoradas ya que influyen en el nivel de satisfacción. Asimismo, la correlación entre la satisfacción y la intención de retornar al centro a futuro evidencian oportunidades de trabajo para administradores e investigadores en el área de la salud.

8.
AAPS J ; 19(6): 1626-1631, 2017 11.
Artigo em Inglês | MEDLINE | ID: mdl-28895076

RESUMO

As part of our ongoing research into botanical therapies for anxiety disorders, the neotropical vine Souroubea sympetala was chosen for study as a phytochemical discovery strategy focusing on rare Central American plant families. When orally administered to male Sprague-Dawley rats, the crude plant extract, its ethyl acetate fraction, supercritical carbon dioxide fraction, or its isolated triterpenes reduced anxiety and/or fear-related behavior in standardized behavioral models. Pharmacological studies showed that the extracts acted at the benzodiazepine GABAA receptor and reduced corticosterone levels. A preparation containing Souroubea fortified with a second triterpene containing plant, Platanus occidentalis, was shown to be safe in a 28-day feeding trial with beagles at 5 times the intended dose. Subsequent trials with beagles in a thunderstorm model of noise aversion showed that the material reduced anxiety behaviors and cortisol levels in dogs. The formulation has been released for the companion animal market in Canada and the USA under the Trademark "Zentrol." Ongoing research is exploring the use of the material in treatment of anxiety and post-traumatic stress in humans.


Assuntos
Ansiolíticos/uso terapêutico , Fitoterapia , Animais , Ensaios Clínicos como Assunto , Estabilidade de Medicamentos , Humanos , Extratos Vegetais/farmacologia , Extratos Vegetais/uso terapêutico , Ratos , Ratos Sprague-Dawley , Receptores de GABA-A/efeitos dos fármacos
9.
Phytother Res ; 30(3): 439-46, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26666462

RESUMO

Bioassay-guided fractionation of the crude extract (80% EtOH) of the leaves of Cestrum schlechtendahlii, a plant used by Q'eqchi' Maya healers for treatment of athlete's foot, resulted in the isolation and identification of two spirostanol saponins (1 and 2). Structure elucidation by MS, 1D-NMR, and 2D-NMR spectroscopic methods identified them to be the known saponin (25R)-1ß,2α-dihydroxy-5α-spirostan-3-ß-yl-O-α-L-rhamnopyranosyl-(1 → 2)-ß-D-galactopyranoside (1) and new saponin (25R)-1ß,2α-dihydroxy-5α-spirostan-3-ß-yl-O-ß-D-galactopyranoside (2). While 2 showed little or no antifungal activity at the highest concentration tested, 1 inhibited growth of Saccharomyces cerevisiae (minimum inhibitory concentration (MIC) of 15-25 µM), Candida albicans, Cryptococcus neoformans, and Fusarium graminearum (MIC of 132-198 µM).


Assuntos
Antifúngicos/farmacologia , Cestrum/química , Fungos/efeitos dos fármacos , Extratos Vegetais/farmacologia , Saponinas/farmacologia , Espirostanos/farmacologia , Antifúngicos/química , Antifúngicos/isolamento & purificação , Candida albicans/efeitos dos fármacos , Cryptococcus neoformans/efeitos dos fármacos , Etnicidade , Fusarium/efeitos dos fármacos , Humanos , Espectroscopia de Ressonância Magnética , Medicina Tradicional , Testes de Sensibilidade Microbiana , Estrutura Molecular , Fitoterapia , Extratos Vegetais/química , Folhas de Planta/química , Plantas Medicinais , Saccharomyces cerevisiae/efeitos dos fármacos , Saponinas/química , Saponinas/isolamento & purificação , Solanaceae , Espirostanos/química , Espirostanos/isolamento & purificação
10.
Planta Med ; 80(4): 343-50, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24488718

RESUMO

Bacterial biofilms are responsible for many persistent infections by many clinically relevant pathogens such as Staphylococcus aureus and Pseudomonas aeruginosa. Biofilms are much more resistant to conventional antibiotics than their planktonic counterparts. Quorum sensing, an intercellular communication system, controls pathogenesis and biofilm formation in most bacterial species. Quorum sensing provides an important pharmacological target since its inhibition does not provide a selective pressure for resistance. In this study, we investigated the quorum sensing and biofilm inhibitory activities of 126 plant extracts from 71 species collected from neotropical rainforests in Costa Rica. Quorum sensing and biofilm interference were assessed using a modified disc diffusion bioassay with Chromobacterium violaceum ATCC 12,472 and a spectrophotometric bioassay with Pseudomonas aeruginosa PA14, respectively. Species with significant anti-quorum sensing and/or anti-biofilm activities belonged to the Meliaceae, Melastomataceae, Lepidobotryaceae, Sapindaceae, and Simaroubaceae families. IC50 values ranged from 45 to 266 µg/mL. Extracts of these active species could lead to future development of botanical treatments for biofilm-associated infections.


Assuntos
Antibacterianos/farmacologia , Biofilmes/efeitos dos fármacos , Chromobacterium/efeitos dos fármacos , Magnoliopsida/química , Extratos Vegetais/farmacologia , Pseudomonas aeruginosa/efeitos dos fármacos , Percepção de Quorum/efeitos dos fármacos , Costa Rica , Árvores , Clima Tropical
11.
Bol. latinoam. Caribe plantas med. aromát ; 10(2): 155-158, mar. 2011. ilus
Artigo em Inglês | LILACS | ID: lil-686995

RESUMO

Following our phytochemical studies of Costa Rican plants, in this work we report the isolation and identification of eight compounds from aerial parts of Zanthoxylum setulosum (Rutaceae). They were identified as the alkaloid skimmianine, the lignans savinin, kusunokinin, sesamin, syringaresinol and the isopentenyl ether of pluviatol, the amide aurantiamide acetate, and the triterpen lupeol. This is the first report of isolation of skimmianine from the leaves of Z. setulosum and its presence confirm that quinoline and benzophenanthridine alkaloids, can be considered as chemotaxonomic markers of this genus. All the isolated compounds were characterized by spectroscopic methods (including 1H-NMR, 13C-NMR, , HMQC, HMBC and NOESY) and comparison with the literature data.


Continuando con el estudio fitoquímico de plantas de Costa Rica, en este trabajo informamos el aislamiento e identificación de ocho compuestos de las partes aéreas de Zanthoxylum setulosum (Rutaceae). Los compuestos fueron identificados como el alcaloide skimmianina, los lignanos savinina, kusunokinina, sesamina, siringaresinol y el éter isopentílico del pluviatol, la amida conocida como acetato de aurantiamida, y el triterpeno lupeol. Este es el primer informe del aislamiento de skimmianina en las hojas de Z. setulosum, lo cual confirma que alcaloides quinolínicos y benzofenantridinicos pueden ser considerados marcadores quimiotaxonómicos en éste género. La estructura de los compuestos aislados fue caracterizada por métodos espectroscópicos (incluyendo 1HNMR, 13C-NMR, HMQC, HMBC y NOESY) y comparación con datos de la literatura.


Assuntos
Alcaloides/isolamento & purificação , Folhas de Planta/química , Lignanas/isolamento & purificação , Quinolinas/isolamento & purificação , Zanthoxylum/química , Rutaceae/química , Análise Espectral
12.
J Ethnopharmacol ; 133(2): 907-10, 2011 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-20937373

RESUMO

AIM OF THE STUDY: Witheringia solanacea is a small shrub that belongs to the Solanaceae family. The plant is used as an antidiabetic in Costa Rican herbal medicine. The aim of this study was to evaluate the hypoglycemic and antihyperglycemic activity of the aqueous extract of W. solanacea leaves in rodent models. MATERIALS AND METHODS: A crude extract of W. solanacea leaves was prepared in boiling water and the aqueous filtrate was lyophilized. A single oral dose of 250, 500 and 1000 mg/kg of the extract was evaluated for hypoglycemic activity in a glucose tolerance test in normal rats and for antihyperglycemic activity in alloxan-induced (140 mg/kg) diabetic rats. The blood glucose level was determined at different times by the glucose oxidase method. RESULTS: Dosage of 500 and 1000 mg/kg of the extract significantly decreased (p<0.05) blood glucose levels in the glucose tolerance test in normal rats after 1 h, there was no significant difference observed at 250 mg/kg. Dose of 500 mg/kg of the extract significantly reduced (p<0.05) blood glucose levels in alloxan induced hyperglycemic rats at 4 and 5 h. CONCLUSIONS: In the present study, the hypoglycemic and antihyperglycemic potential of the W. solanacea was demonstrated in rats. These results give support to the traditional use of W. solanacea as antidiabetic herbal medicine.


Assuntos
Diabetes Mellitus Experimental/tratamento farmacológico , Hiperglicemia/tratamento farmacológico , Hipoglicemiantes/farmacologia , Fitoterapia , Solanaceae , Animais , Glicemia/metabolismo , Costa Rica , Diabetes Mellitus Experimental/sangue , Etnofarmacologia , Teste de Tolerância a Glucose , Hiperglicemia/sangue , Hipoglicemiantes/isolamento & purificação , Masculino , Medicina Tradicional , Extratos Vegetais/farmacologia , Folhas de Planta/química , Plantas Medicinais/química , Ratos , Ratos Sprague-Dawley , Solanaceae/química
13.
Phytother Res ; 25(2): 264-70, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20648677

RESUMO

The purpose of this work was to develop an extraction technique to yield a betulinic acid-(BA) enriched extract of the traditional anti-anxiety plant Souroubea sympetala Gilg (Marcgraviaceae). Five extraction techniques were compared: supercritical carbon dioxide extraction (SCE), conventional solvent extraction with ethyl acetate (EtOAc), accelerated solvent extraction (ASE), ultrasonic assisted extraction (UAE) and soxhlet extraction (Sox). The EtOAc and SCE extraction methods resulted in BA-enriched extracts, with BA concentrations of 6.78 ± 0.2 and 5.54 ± 0.2 mg/g extract, respectively, as determined by HPLC-APCI-MS. The bioactivity of the BA-enriched extracts was compared in the elevated plus maze (EPM), a validated rodent anxiety behaviour assay. Rats orally administered a 75 mg/kg dose of SCE extract exhibited anxiolysis as compared with vehicle controls, with a 50% increase in the percent time spent in the open arms, a 73% increase in unprotected head dips and a 42% decrease in percent time spent in the closed arms. No significant differences were observed between the SCE and EtOAc extracts for these measures, but the animals dosed with SCE extract had significantly more unprotected head dips than those dosed with the EtOAc extract. The SCE extract demonstrated a dose-response in the EPM, with a trend toward decreased anxiety at 25 mg/kg, and significant anxiolysis was only observed at 75 mg/kg dose. This study demonstrates that SCE can be used to generate a betulinic acid-enriched extract with significant anxiolysis in vivo. Further, the study provides a scientific basis for the ethnobotanical use of this traditional medicine and a promising lead for a natural health product to treat anxiety.


Assuntos
Ansiolíticos/farmacologia , Ansiedade/tratamento farmacológico , Extratos Vegetais/farmacologia , Triterpenos/farmacologia , Animais , Comportamento Exploratório/efeitos dos fármacos , Magnoliopsida/química , Masculino , Aprendizagem em Labirinto/efeitos dos fármacos , Triterpenos Pentacíclicos , Ratos , Ratos Sprague-Dawley , Ácido Betulínico
14.
Phytochemistry ; 71(11-12): 1418-22, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20580789

RESUMO

Five spirocaracolitone triterpenoids were isolated from the dichloromethane-soluble fraction of the bark of Ruptiliocarpon caracolito, and their structures were determined mainly by application of 1D and 2D NMR spectroscopy. Two known CD-spirotriterpenoids were also isolated from the same source. This brings the total number of known CD-spirotriterpenoids from this source to 17. The discovery of such a large number of closely-related compounds in a single species represents an excellent example of phytochemical redundancy as a defense mechanism.


Assuntos
Celastraceae/química , Triterpenos/isolamento & purificação , Costa Rica , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular , Casca de Planta/química , Triterpenos/química
15.
J Ethnopharmacol ; 125(2): 257-64, 2009 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-19591913

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: The Q'eqchi' Maya possess a large selection of plants to treat neurological disorders, including epilepsy and susto (fright), a culture-bound illness related to anxiety disorders. AIM OF THE STUDY: To investigate the activity of antiepileptic and anxiolytic plants in the GABAergic system, and determine if there is a pharmacological basis for plant selection. MATERIALS AND METHODS: Ethanol extracts of 34 plants were tested in vitro for their ability to inhibit GABA-transaminase (GABA-T) or bind to the GABA(A)-benzodiazepine (BZD) receptor, two principal drug targets in epilepsy and anxiety. Pharmacological activity was correlated with relative frequency of use, based on informant consensus. RESULTS: Ten plants showed greater than 50% GABA-T inhibition at 1mg/ml, while 23 showed greater than 50% binding to the GABA(A)-BZD receptor at 250 microg/ml. Piperaceae, Adiantaceae and Acanthaceae families were highly represented and active in both assays. There was a significant positive correlation between GABA-T inhibition and relative frequency of use for epilepsy, and an even stronger correlation between GABA(A) binding and relative frequency of use for susto (fright). CONCLUSIONS: Clearly, Q'eqchi' traditional knowledge of antiepileptic and anxiolytic plants is associated with the use of pharmacologically active plants. Based on the evidence, it is suggested that the mechanism of action for some traditionally used plants may be mediated through the GABAergic system.


Assuntos
4-Aminobutirato Transaminase/antagonistas & inibidores , Ansiolíticos/farmacologia , Anticonvulsivantes/farmacologia , Epilepsia/tratamento farmacológico , Magnoliopsida , Extratos Vegetais/farmacologia , Receptores de GABA-A/metabolismo , Ansiolíticos/uso terapêutico , Anticonvulsivantes/uso terapêutico , Ansiedade/tratamento farmacológico , Belize , Etnofarmacologia , Humanos , Indígenas Centro-Americanos , Medicina Tradicional , Fitoterapia , Extratos Vegetais/química , Extratos Vegetais/uso terapêutico , Plantas Medicinais , Taninos/análise
16.
Rev. biol. trop ; 56(3): 1043-1051, sep. 2008. ilus, tab
Artigo em Espanhol | LILACS | ID: lil-637845

RESUMO

Four new compounds from the non-polar extract of the plant Amyris brenesii (Rutaceae) from Costa Rica. Fractionation of a non polar extract of the aerial parts of Amyris brenesii collected in Río Cuarto, Grecia, Costa Rica has resulted in the isolation of four new compounds, 6-hidroxy-6-O-(3-hidroxymethyl-3methylalyl)-angelicin 1, 6-(N-acetyl-2-etanamin)-2,2-dimethyl-2H-cromen 2, the lignan 2,5-dehidrohinokinin 3 and N-acetyl-O-(geranyl)-tiramine 4. In addition, we isolated six previously known compounds: the lignans hinokinin 5 and Justicidin E 6, the coumarins scopoletin 7 and marmesin 8, 24-moretenoic acid 9, and the nitrogen compound O-(3,3-dimethylalyl)-halfordinol 10. All the separations were done with chromatographic techniques and the structures were elucidated by using 1D and 2D NMR techniques. Rev. Biol. Trop. 56 (3): 1043-1052. Epub 2008 September 30.


El estudio fitoquímico de las partes aéreas de Amyris brenesii (Rutaceae) recolectadas en Río Cuarto, Grecia, Alajuela (Costa Rica) mostró la presencia de cuatro nuevos compuestos: la 6-hidroxi-6-O-(3-hidroximetil-3-metilalil)angelicina 1, el 6-(N-acetil-2-etanamin)-2,2-dimetil-2Hcromeno 2, el lignano 2,5-deshidrohinokinina 3 y la N-acetil-O-(geranil)-tiramina 4. Adicionalmente se aislaron los lignanos hinokinina 5, y justicidina E 6, las cumarinas escopoletina 7 y marmesina 8, el ácido 24-moretenoico 9 y el O-(3,3-dimetilalil)-halfordinol 10. Las separaciones se llevaron a cabo mediante la aplicación de técnicas cromatográficas y la elucidación de las estructuras se realizó con la ayuda de técnicas espectroscópicas de Resonancia Magnética Nuclear (RMN) de una y dos dimensiones.


Assuntos
Extratos Vegetais/química , Rutaceae/química , Cromatografia , Costa Rica , Espectroscopia de Ressonância Magnética
17.
Rev Biol Trop ; 56(3): 1043-51, 2008 Sep.
Artigo em Espanhol | MEDLINE | ID: mdl-19419026

RESUMO

Fractionation of a non polar extract of the aerial parts of Amyris brenesii collected in Rio Cuarto, Grecia, Costa Rica has resulted in the isolation of four new compounds, 6-hidroxy-6-O-(3-hidroxymethyl-3-methylalyl)-angelicin 1, 6-(N-acetyl-2-etanamin)-2,2-dimethyl-2H-cromen 2, the lignan 2,5-dehidrohinokinin 3 and N-acetyl-O-(geranyl)-tiramine 4. In addition, we isolated six previously known compounds: the lignans hinokinin 5 and Justicidin E 6, the coumarins scopoletin 7 and marmesin 8, 24-moretenoic acid 9, and the nitrogen compound O-(3,3-dimethylalyl)-halfordinol 10. All the separations were done with chromatographic techniques and the structures were elucidated by using 1D and 2D NMR techniques.


Assuntos
Extratos Vegetais/química , Rutaceae/química , Cromatografia , Costa Rica , Espectroscopia de Ressonância Magnética
18.
J Nat Prod ; 70(8): 1228-32, 2007 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-17665950

RESUMO

Six new triterpenoids named spirocarcolitones (G-L), which belong to a novel class of CD-spiro triterpenoids, were isolated from the dichloromethane-soluble fraction of the bark of Ruptiliocarpon caracolito. The structures of these natural products were established using mainly 1D and 2D NMR spectroscopy. One known CD-spiro triterpenoid and canophyllol were also isolated from the same source.


Assuntos
Celastraceae/química , Triterpenos/química , Triterpenos/isolamento & purificação , Costa Rica , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular , Casca de Planta/química , Triterpenos/classificação
19.
Rev. biol. trop ; 54(2): 245-252, jun. 2006. graf
Artigo em Inglês | LILACS | ID: lil-492074

RESUMO

We tested the capacity of leaf (Urera baccifera, Loasa speciosa, Urtica leptuphylla, Chaptalia nutans, and Satureja viminea) and root (Uncaria tomentosa) extracts to inhibit edema induced by Bothrops asper snake venom. Edema-forming activity was studied plethysmographically in the rat hind paw model. Groups of rats were injected intraperitoneally with various doses of each extract and, one hour later, venom was injected subcutaneously in the right hind paw. Edema was assessed at various time intervals. The edematogenic activity was inhibited in those animals that received an injection U. tomentosa, C. nutans or L. speciosa extract. The extract of U. baccifera showed a slight inhibition of the venom effect. Extract from S. viminea and, to a lesser extent that of U. leptuphylla, induced a pro-inflammatory effect, increasing the edema at doses of 250 mg/kg at one and two hours.


Se investigó la capacidad de los extractos de las hojas de Urera baccifera, Loasa speciosa, Urtica leptuphylla, Chaptalia nutans, Satureja viminea y de la raíz de Uncaria tomentosa para inhibir el edema inducido por el veneno de Bothrops asper por métodos pletismométricos. Los grupos de ratas fueron inyectados intraperitonealmente con varias dosis de cada extracto y una hora mas tarde se inyectó veneno por vía subcutánea en la pata trasera derecha de la rata. Se evaluó el edema en distintos intervalos de tiempo. Los resultados muestran que la actividad edematogénica fue inhibida en los animales que recibieron los extractos de raíz de U. tomentosa, hojas de C. nutans y L. speciosa. Los extractos de hojas de U. baccifera mostraron leve inhibición del efecto del veneno. El extracto de hojas de S. viminea y en menor grado el de U. leptuphylla indujeron un efecto pro inflamatorio.


Assuntos
Animais , Masculino , Ratos , Anti-Inflamatórios , Bothrops , Edema/tratamento farmacológico , Extratos Vegetais/uso terapêutico , Fitoterapia , Venenos de Crotalídeos/toxicidade , Anti-Inflamatórios , Antivenenos/uso terapêutico , Costa Rica , Edema/induzido quimicamente , Extratos Vegetais/química , Modelos Animais de Doenças , Ratos Sprague-Dawley , Venenos de Crotalídeos/antagonistas & inibidores
20.
Rev Biol Trop ; 54(2): 245-52, 2006 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18494294

RESUMO

We tested the capacity of leaf (Urera baccifera, Loasa speciosa, Urtica leptuphylla, Chaptalia nutans, and Satureja viminea) and root (Uncaria tomentosa) extracts to inhibit edema induced by Bothrops asper snake venom. Edema-forming activity was studied plethysmographically in the rat hind paw model. Groups of rats were injected intraperitoneally with various doses of each extract and, one hour later, venom was injected subcutaneously in the right hind paw. Edema was assessed at various time intervals. The edematogenic activity was inhibited in those animals that received an injection U. tomentosa, C. nutans or L. speciosa extract. The extract of U. baccifera showed a slight inhibition of the venom effect. Extract from S. viminea and, to a lesser extent that of U. leptuphylla, induced a pro-inflammatory effect, increasing the edema at doses of 250 mg/kg at one and two hours.


Assuntos
Anti-Inflamatórios/uso terapêutico , Bothrops , Venenos de Crotalídeos/toxicidade , Edema/tratamento farmacológico , Fitoterapia , Extratos Vegetais/uso terapêutico , Animais , Anti-Inflamatórios/farmacologia , Antivenenos/uso terapêutico , Costa Rica , Venenos de Crotalídeos/antagonistas & inibidores , Modelos Animais de Doenças , Edema/induzido quimicamente , Masculino , Extratos Vegetais/química , Ratos , Ratos Sprague-Dawley
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