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1.
J Endod ; 49(2): 155-161, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36526106

RESUMEN

INTRODUCTION: YouTube is one of the most used social media platforms for health care information. Misinformation and poor educational content on this platform can exacerbate public anxiety and fear of root canal treatment. This study aimed to investigate the quality of videos examining risks of root canal treatment on YouTube. METHODS: YouTube was searched using a combination of keywords relating to endodontic complications to replicate goal-orientated browsing. Video quality was assessed using a modified DISCERN score and global quality score by 2 authors independently. Manifest quantitative content analysis was used to capture information about the video and extent of interactions. The 10 most viewed videos were further analyzed in terms of the messaging and format of the videos. RESULTS: The mean overall quality of the videos was relatively low (2.20). Videos produced by regulatory bodies had the highest mean score (3.00) and the shortest mean length (2 minutes 23 seconds) but had the fewest views and interactions. The poorest quality videos (mean 1.5) were produced by nonclinicians and news/media, which tended to be longer (mean 8 minutes 49 seconds) and received more engagement. Across all videos, information related to patient decision making tended to be poorly presented. CONCLUSIONS: The dental community, particularly institutions and organizations, need to strategically create engaging videos to redress patients' concerns about root canal treatment. This can counterbalance the existing misleading information and improve access to evidence-based content, which will ultimately affect patient decision making.


Asunto(s)
Difusión de la Información , Tratamiento del Conducto Radicular , Medios de Comunicación Sociales , Humanos , Cavidad Pulpar , Fuentes de Información , Reproducibilidad de los Resultados , Grabación en Video
2.
Nat Prod Commun ; 5(6): 859-62, 2010 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-20614809

RESUMEN

Two new tetranortriterpenoids were obtained by chromatography of the acetone extract of the wood of Spathelia sorbifolia L.; these compounds were characterized as their p-bromobenzoyl derivatives (2, 3). This extract also yielded a known tetranortriterpenoid and the chromones allopteroxylin, spatheliabischromene and anhydrosorbifolin.


Asunto(s)
Limoninas/química , Rutaceae/química , Estructura Molecular , Madera/química
3.
J Nat Prod ; 69(9): 1315-8, 2006 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-16989526

RESUMEN

A chemical investigation of the bark of Simarouba amara, collected in Barbados, resulted in the isolation of six new triterpenes (3-8), in addition to two known compounds, 3-oxatirucalla-7, 24-dien-23-ol (1) and niloticin (2). Compound 3 is a tirucallane triterpene, while compounds 4-7 are apotirucallane derivatives containing an epsilon-lactone in ring A. Compounds 6 and 7 were obtained as a mixture that could not be separated, while compound 8 is an octanorapotirucallane derivative that lacks the C(8) side chain. The structures of all compounds were determined by interpretation of physical data.


Asunto(s)
Plantas Medicinales/química , Simarouba/química , Triterpenos/química , Triterpenos/aislamiento & purificación , Barbados , Estructura Molecular , Resonancia Magnética Nuclear Biomolecular
4.
Fitoterapia ; 75(7-8): 634-8, 2004 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-15567237

RESUMEN

Four steroidal saponins were isolated from the leaves of Furcraea selloa var. marginata. These included one furostanol saponin, furcreafurostatin (1), and three known spirostanol saponins, furcreastatin (3), yuccaloeside C (4) and cantalasaponin-1 (5). The 22-O-methyl ether (2) of furcreafurostatin (1) was also characterized. The structures were determined by using a combination of spectroscopic techniques.


Asunto(s)
Asparagaceae , Fitoterapia , Extractos Vegetales/química , Saponinas/química , Humanos , Espectroscopía de Resonancia Magnética , Hojas de la Planta
5.
J Nat Prod ; 67(4): 714-7, 2004 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-15104513

RESUMEN

Seven new labdane diterpenes, sibiricinones A-E (1-4, 6) and 15-epi-sibiricinones D and E (5 and 7), and the flavone genkwanin were isolated from the aerial parts of Leonurus sibiricus. Sibiricinone D (4) and 15-epi-sibiricinone D (5), and sibiricinone E (6) and 15-epi-sibiricinone E (7), respectively, were isolated as C-15 epimeric pairs. These secondary metabolites were identified on the basis of 1D and 2D NMR including (1)H-(1)H COSY, HSQC, and HMBC spectroscopic techniques. The stereochemical configurations of compounds 4-7 were assigned through 2D T-ROESY and selective NOE experiments.


Asunto(s)
Diterpenos/aislamiento & purificación , Leonurus/química , Plantas Medicinales/química , Barbados , Diterpenos/química , Estructura Molecular , Resonancia Magnética Nuclear Biomolecular
6.
Phytochemistry ; 64(7): 1303-7, 2003 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-14599529

RESUMEN

Three pyrones and a 2(5H)-furanone, designated pectinolides D-G, have been isolated from the dichloromethane extract of Hyptis pectinata. The metabolites were characterized on the basis of 1D and 2D NMR spectroscopic techniques. The pyrones were identified as 6S-[3S,6S-(diacetoxy)-5R-hydroxy-1Z-heptenyl]-5S-hydroxy-5,6-dihydro-2H-pyran-2-one (1)- pectinolide D, 6S-[3S,5R,6S-(triacetoxy)-1Z-heptenyl]-5S-acetoxy-5,6-dihydro-2H-pyran-2-one (2)- pectinolide E and 6S-[3S,5R,6S-(triacetoxy)-1Z-heptenyl]-5S-acetoxy-4R-methoxy-3,4,5,6-tetrahydro-4H pyran-2-one (3)- pectinolide F. The furanone was identified as [2'Z,5(1')Z] 5-(4'S,6'R,7'S-triacetoxy-2-octenylidene)-2(5H)-furanone (4)-pectinolide G.


Asunto(s)
Furanos/química , Hyptis/química , Pironas/química , Furanos/aislamiento & purificación , Estructura Molecular , Resonancia Magnética Nuclear Biomolecular , Componentes Aéreos de las Plantas/química , Pironas/aislamiento & purificación , Estereoisomerismo
7.
J Nat Prod ; 66(10): 1378-81, 2003 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-14575441

RESUMEN

Five new cassane diterpenoids (1-5) were isolated from the roots of Caesalpinia pulcherrima, along with the known isovouacapenol C (6), pulcherrimin A (11), and 6beta-cinnamoyl-7beta-hydroxyvouacapen-5alpha-ol (12). Compounds 3-5 possess the alpha,beta-butenolide moiety, whereas compounds 1 and 2 contain a more usual 2,3-disubstituted furan unit. Compounds 7 and 8 were derived from hydrolysis of 6, while 9 and 10 were derived from acetylation and oxidation of 6, respectively. The (1)H and (13)C NMR spectra of all compounds were completely assigned using a combination of 2D NMR experiments, including (1)H-(1)H COSY, HSQC, HMBC, and T-ROESY sequences.


Asunto(s)
Caesalpinia/química , Diterpenos/química , Diterpenos/aislamiento & purificación , Plantas Medicinales/química , Barbados , Estructura Molecular , Resonancia Magnética Nuclear Biomolecular , Raíces de Plantas/química , Estereoisomerismo
8.
J Nat Prod ; 66(9): 1284-7, 2003 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-14510619

RESUMEN

An investigation of the Caribbean octocoral Eunicea tourniforti collected along the southwest coast of Barbados afforded four new cembrane diterpenes, 1, 2, 4, and 5, along with the known cembranolide 3. The structures of all metabolites were determined by spectroscopic methods. Seasonal effects on the secondary metabolite content of the specimens collected were also observed.


Asunto(s)
Antozoos/química , Diterpenos/aislamiento & purificación , Animales , Barbados , Región del Caribe , Diterpenos/química , Conformación Molecular , Espectrometría de Masa por Ionización de Electrospray , Estereoisomerismo
9.
J Nat Prod ; 65(3): 314-8, 2002 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-11908971

RESUMEN

Seven new briarane diterpenes, erythrolides K-Q (1-7), as well as the known compounds erythrolides A, B, C, F, and J have been isolated from samples of the Caribbean gorgonian Erythropodium caribaeorumcollected at Buccoo Reef and Flying Reef, Tobago. The structures of the new compounds were determined by high-resolution 1H and 13C NMR spectroscopy utilizing COSY, HMBC, HMQC, and NOESY experiments. The structures of erythrolides K and P were confirmed and their relative stereochemistry determined by X-ray crystallographic analysis.


Asunto(s)
Cnidarios/química , Diterpenos/aislamiento & purificación , Animales , Cromatografía Líquida de Alta Presión , Cristalografía por Rayos X , Diterpenos/química , Conformación Molecular , Estructura Molecular , Resonancia Magnética Nuclear Biomolecular , Espectrofotometría Ultravioleta , Estereoisomerismo , Trinidad y Tobago
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