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1.
Adv Drug Deliv Rev ; 177: 113915, 2021 10.
Artículo en Inglés | MEDLINE | ID: mdl-34371085

RESUMEN

Evaluation of orally ingestible devices is critical to optimize their performance early in development. Using animals as a pre-clinical tool can provide useful information on functionality, yet it is important to recognize that animal gastrointestinal physiology, pathophysiology and anatomy can differ to that in humans and that the most suitable species needs to be selected to inform the evaluation. There has been a move towards in vitro and in silico models rather than animal models in line with the 3Rs (Replacement, Reduction and Refinement) as well as the better control and reproducibility associated with these systems. However, there are still instances where animal models provide the greatest understanding. This paper provides an overview of key aspects of human gastrointestinal anatomy and physiology and compares parameters to those reported in animal species. The value of each species can be determined based upon the parameter of interest from the ingested device when considering the use of pre-clinical animal testing.


Asunto(s)
Sistemas de Liberación de Medicamentos , Tracto Gastrointestinal , Modelos Animales , Administración Oral , Animales , Formas de Dosificación , Evaluación Preclínica de Medicamentos , Tracto Gastrointestinal/anatomía & histología , Tracto Gastrointestinal/metabolismo , Humanos
3.
Phytochem Anal ; 28(4): 257-266, 2017 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-28124803

RESUMEN

INTRODUCTION: Catha edulis (qat, khat, mirra) is a woody plant species that is grown and consumed in East Africa and Yemen for its stimulant alkaloids cathinone, cathine and norephedrine. Two Celastraceae species, in addition to qat, have been noted for their stimulant properties in ethnobotanical literature. Recent phylogenetic reconstructions place four genera in a clade sister to Catha edulis, and these genera are primary candidates to search for cathine and related alkaloids. OBJECTIVE: Determine if cathine or related alkaloids are present in species of Celastraceae other than Catha edulis. METHODS: Leaf samples from 43 Celastraceae species were extracted in water followed by basification of the aqueous extract and partitioning with methyl-t-butyl ether to provide an alkaloid-enriched fraction. The extract was derivatised in a two-stage process and analysed using GC-MS for the presence of cathine. Related alkaloids and other metabolites in this alkaloid-enriched fraction were tentatively identified. RESULTS: Cathinone, cathine and norephedrine were not detected in any of the 43 Celastraceae species assayed other than Catha edulis. However, the phenylalanine- or tyrosine-derived alkaloid phenylethylamine was identified in five species. Nine species were found to be enriched for numerous sterol- and terpene-like compounds. CONCLUSION: These results indicate that cathine is unique to Catha edulis, and not the compound responsible for the stimulant properties reported in related Celastraceae species. Copyright © 2017 John Wiley & Sons, Ltd.


Asunto(s)
Alcaloides/análisis , Celastraceae/química , Cromatografía de Gases y Espectrometría de Masas , Fenilpropanolamina/análisis , Extractos Vegetales/análisis , Celastraceae/clasificación , Filogenia
4.
New Phytol ; 205(2): 583-95, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25262627

RESUMEN

Past studies have identified herbivory as a likely selection pressure for the evolution of hyperaccumulation, but few have tested the origin(s) of hyperaccumulation in a phylogenetic context. We focused on the evolutionary history of selenium (Se) hyperaccumulation in Stanleya (Brassicaceae). Multiple accessions were collected for all Stanleya taxa and two outgroup species. We sequenced four nuclear gene regions and performed a phylogenetic analysis. Ancestral reconstruction was used to predict the states for Se-related traits in a parsimony framework. Furthermore, we tested the taxa for Se localization and speciation using X-ray microprobe analyses. True hyperaccumulation was found in three taxa within the S. pinnata/bipinnata clade. Tolerance to hyperaccumulator Se concentrations was found in several taxa across the phylogeny, including the hyperaccumulators. X-ray analysis revealed two distinct patterns of leaf Se localization across the genus: marginal and vascular. All taxa accumulated predominantly (65-96%) organic Se with the C-Se-C configuration. These results give insight into the evolution of Se hyperaccumulation in Stanleya and suggest that Se tolerance and the capacity to produce organic Se are likely prerequisites for Se hyperaccumulation in Stanleya.


Asunto(s)
Evolución Biológica , Brassicaceae/metabolismo , Selenio/metabolismo , Brassicaceae/genética , Brassicaceae/fisiología , Filogenia , Hojas de la Planta/genética , Hojas de la Planta/metabolismo , Hojas de la Planta/fisiología
5.
Am J Bot ; 101(5): 830-9, 2014 05.
Artículo en Inglés | MEDLINE | ID: mdl-24752889

RESUMEN

UNLABELLED: • PREMISE OF STUDY: Selenium (Se) hyperaccumulation, the capacity to concentrate the toxic element Se above 1000 mg·kg(-1)·dry mass, is found in relatively few taxa native to seleniferous soils. While Se hyperaccumulation has been shown to likely be an adaptation that protects plants from herbivory, its evolutionary history remains unstudied. Stanleya (Brassicaceae) is a small genus comprising seven species endemic to the western United States. Stanleya pinnata is a hyperaccumulator of selenium (Se). In this study we investigated to what extent other Stanleya taxa accumulate Se both in the field and a greenhouse setting on seleniferous soil.• METHODS: We collected multiple populations of six of the seven species and all four varieties of S. pinnata We tested leaves, fruit, and soil for in situ Se and sulfur (S) concentrations. The seeds collected in the field were used for a common garden study in a greenhouse.• KEY RESULTS: We found that S. pinnata var. pinnata is the only hyperaccumulator of Se. Within S. pinnata var. pinnata, we found a geographic pattern related to Se hyperaccumulation where the highest accumulating populations are found on the eastern side of the continental divide. We also found differences in genome size within the S. pinnata species complex.• CONCLUSIONS: The S. pinnata species complex has a range of physiological properties making it an attractive system to study the evolution of Se hyperaccumulation. Beyond the basic scientific value of understanding the evolution of this fascinating trait, we can potentially use S. pinnata or its genes for environmental cleanup and/or nutrient-enhanced dietary material.


Asunto(s)
Brassicaceae/metabolismo , Selenio/metabolismo , Azufre/metabolismo , Brassicaceae/clasificación , Suelo/química
6.
J Am Geriatr Soc ; 61(9): 1552-9, 2013 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-24028358

RESUMEN

OBJECTIVES: To test the effectiveness of a pressure ulcer (PU) prevention intervention featuring musical cues to remind all long-term care (LTC) staff (nursing and ancillary) to help every resident move or reposition every 2 hours. DESIGN: Twelve-month paired-facility two-arm (with one-arm crossover) randomized intervention trial. SETTING: Ten midwestern U.S. LTC facilities. Four treatment facilities received intervention during Months 1 to 12, four comparison facilities received intervention during Months 7 to 12, and two pseudo-control facilities received no intervention. PARTICIPANTS: LTC facility residents (N = 1,928). INTERVENTION: All facility staff received in-person education, video, and handouts, and visiting family members received informational pamphlets on PU prevention and an intervention featuring musical cues. Nurse-led multidisciplinary staff teams presented the cues as prompts for staff and family to reposition residents or remind them to move. Musical selections (with and without lyrics) customized to facility preferences were played daily over the facility intercom or public address system every 2 hours for the 12-hour daytime period. MEASUREMENTS: Primary outcome measure was the frequency of new facility-acquired PUs divided by the total number of facility Minimum Data Set (MDS) resident assessments conducted during the study period. RESULTS: Odds of a new PU were lower in intervention facilities (P = .08) for MDS 2.0 assessments and were significantly lower (P = .05) for MDS 3.0. Mean odds ratios suggested intervention facility residents were 45% less likely than comparison facility residents to develop a new PU. CONCLUSION: Customized musical cues that prompt multidisciplinary staff teams to encourage or enable movement of all residents hold promise for reducing facility-acquired PUs in LTC settings.


Asunto(s)
Señales (Psicología) , Hogares para Ancianos , Cuidados a Largo Plazo/métodos , Musicoterapia/métodos , Úlcera por Presión/prevención & control , Anciano , Femenino , Estudios de Seguimiento , Humanos , Incidencia , Masculino , Oportunidad Relativa , Úlcera por Presión/epidemiología , Factores de Riesgo , Índice de Severidad de la Enfermedad , Factores de Tiempo , Resultado del Tratamiento , Estados Unidos/epidemiología
7.
Mol Phylogenet Evol ; 62(1): 9-20, 2012 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-22001302

RESUMEN

The phylogeny of Celastraceae tribe Euonymeae (≈ 230 species in eight genera in both the Old and New Worlds) was inferred using morphological characters together with plastid (matK, trnL-F) and nuclear (ITS and 26S rDNA) genes. Tribe Euonymeae has been defined as those genera of Celastraceae with generally opposite leaves, isomerous carpels, loculicidally dehiscent capsules, and arillate seeds (except Microtropis). Euonymus is the most diverse (129 species) and widely cultivated genus in the tribe. We infer that tribe Euonymeae consists of at least six separate lineages within Celastraceae and that a revised natural classification of the family is needed. Microtropis and Quetzalia are inferred to be distinct sister groups that together are sister to Zinowiewia. The endangered Monimopetalum chinense is an isolated and early derived lineage of Celastraceae that represents an important component of phylogenetic diversity within the family. Hedraianthera is sister to Brassiantha, and we describe a second species (Brassiantha hedraiantheroides A.J. Ford) that represents the first reported occurrence of this genus in Australia. Euonymus globularis, from eastern Australia, is sister to Menepetalum, which is endemic to New Caledonia, and we erect a new genus (Dinghoua R.H. Archer) for it. The Madagascan species of Euonymus are sister to Pleurostylia and recognized as a distinct genus (Astrocassine ined.). Glyptopetalum, Torralbasia, and Xylonymus are all closely related to Euonymus sensu stricto and are questionably distinct from it. Current intrageneric classifications of Euonymus are not completely natural and require revision.


Asunto(s)
Euonymus/clasificación , Genes de Plantas , Filogenia , Plastidios/genética , ADN Espaciador Ribosómico/genética , Euonymus/anatomía & histología , Euonymus/genética , Flores/anatomía & histología , Funciones de Verosimilitud , Hojas de la Planta/anatomía & histología , Polen/anatomía & histología , ARN Ribosómico/genética , Semillas/anatomía & histología , Alineación de Secuencia , Análisis de Secuencia de ADN
8.
Phytochemistry ; 72(1): 21-6, 2011 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-21094504

RESUMEN

Tripterygium wilfordii Hook.f., known as Leigongteng (Thunder God Vine) in traditional Chinese medicine, has attracted much attention for its applications in relieving autoimmune disorders such as rheumatoid arthritis and systemic lupus erythematosus, and for treating cancer. Molecular analyses of the ITS and 5S rDNA sequences indicate that T. hypoglaucum and T. doianum are not distinct from T. wilfordii, while T. regelii should be recognized as a separate species. The results also demonstrate potential value of rDNA sequence data in forensic detection of adulterants derived from Celastrus angulatus in commercial samples of Leigongteng.


Asunto(s)
Medicamentos Herbarios Chinos/química , Tripterygium/química , Tripterygium/genética , ADN/química , ADN/genética , Bases de Datos Genéticas , Medicamentos Herbarios Chinos/análisis , Filogenia , Homología de Secuencia de Ácido Nucleico , Especificidad de la Especie
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