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2.
J Emerg Nurs ; 40(5): 434-9, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24269063

RESUMO

INTRODUCTION: Interruptions have been shown to cause errors and delays in the treatment of emergency patients and pose a real threat during the triage process. Missteps during the triage assessment can send a patient down the wrong treatment path and lead to delays. The purpose of this project was to identify the types and frequency of interruptions during the ED triage interview process. METHODS: A focus group of emergency nurses was organized to identify the types of interruptions that commonly occur during the triage interview. These interruptions would be validated through observations in triage. A tally sheet was developed and implemented to determine how often each interruption occurred during an 8-hour shift. Triage nurses completed the tally sheets while working the first shift (7 am to 3 pm). This shift was selected because patient intake in the US Department of Veterans Affairs Emergency Department is highest during this time. RESULTS: The categories of interruptions identified included provision of conveniences to visitors, coworker-related interruptions, patient care-related interruptions, locating of family members in the emergency department, and other miscellaneous interruptions. Tally sheets were completed by the triage nurses during 10 shifts. On average, triage nurses were interrupted 48.2 times during an 8-hour shift (7 interruptions per hour). After reviewing the data, we found that only 22% of interruptions were related to patient care. More frequently, the causes of interruptions were not related to patient care: opening the door (33%), providing conveniences to visitors (21%), waiting patients or family members asking "How much longer?" (14%), and other causes (10%). DISCUSSION: Frequent interruptions can interfere with concentration and may affect patient care. Non-patient care-related interruptions not only can be frustrating to the triage nurse but also can be offensive to triage patients; they ultimately delay care and may even affect the quality of care. However, because scarce research is available regarding interruptions during ED triage, the effects on patient outcomes are unclear. Additional research needs to be conducted to explore the causes and effects of interruptions to the triage process.


Assuntos
Continuidade da Assistência ao Paciente , Enfermagem em Emergência , Serviço Hospitalar de Emergência/organização & administração , Avaliação de Processos em Cuidados de Saúde , Triagem , Carga de Trabalho , Hospitais de Veteranos , Humanos , Avaliação em Enfermagem , Melhoria de Qualidade , Fatores de Tempo , Estados Unidos
3.
J Biomol Tech ; 18(4): 238-44, 2007 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17916796

RESUMO

Several species in the genus Echinacea are beneficial herbs popularly used for many ailments. The most popular Echinacea species for cultivation, wild collection, and herbal products include E. purpurea (L.) Moench, E. pallida (Nutt.) Nutt., and E. angustifolia (DC). Product adulteration is a key concern for the natural products industry, where botanical misidentification and introduction of other botanical and nonbotanical contaminants exist throughout the formulation and production process. Therefore, rapid and cost-effective methods that can be used to monitor these materials for complex product purity and consistency are of benefit to consumers and producers. The objective of this continuing research was to develop automated, high-throughput processing methods that, teamed with matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) analysis, differentiate Echinacea species by their mass profiles. Small molecules, peptide, and proteins from aerial parts (leaf/stem/flowers), seeds, and roots from E. purpurea and E. angustifolia; seeds and roots from E. pallida; and off-the-shelf Echinacea supplements were extracted and analyzed by MS using methods developed on the ProPrep liquid handling system (Genomic Solutions). Analysis of these samples highlighted key MS signal patterns from both small molecules and proteins that characterized the individual Echinacea materials analyzed. Based on analysis of pure Echinacea samples, off-the-shelf products containing Echinacea could then be evaluated in a streamlined process. Corresponding analysis of dietary supplements was used to monitor for product composition, including Echinacea species and plant materials used. These results highlight the potential for streamlined, automated approaches for agricultural species differentiation and botanical product evaluation.


Assuntos
Biomarcadores/química , Echinacea/química , Robótica , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos
4.
J AOAC Int ; 90(5): 1203-9, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17955963

RESUMO

Advancements in automated high-performance thin-layer chromatography (HPTLC) have made it feasible to assess its use for the quantitative analysis of marker compounds in botanical preparations. We report here the findings of method comparisons for the terpenelactones and flavonol aglycones by column high-performance liquid chromatography (HPLC) with evaporative light scattering and UV detection, and HPTLC with a scanning densitometer. For the HPTLC assay of terpenelactones, total bilobalide, ginkgolide A, and ginkgolide B consistently achieved <70% of the total determined using HPLC, regardless of variations to postchromatographic derivatization time and temperature. Accuracy testing showed the possibility of a matrix interference. In contrast, a good relationship (95%) was determined between HPTLC and HPLC for determination of total flavonol glycosides (calculated from combined quercetin, kaempferol, and isorhamnetin) from an acid-hydrolyzed Ginkgo biloba L. (GBE) sample. The HPTLC flavonol aglycone method also performed well in terms of accuracy (overall average of 96% recovery for the 3 aglycones) and consecutive plate repeatability (overall percent relative standard deviation of 4.4). It is demonstrated that HPTLC can be a time-saving complement to HPLC for routine analysis of the flavonol glycosides in GBE.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Cromatografia em Camada Fina/métodos , Doxorrubicina/análogos & derivados , Flavonóis/química , Ginkgo biloba/metabolismo , Lactonas/química , Extratos Vegetais/metabolismo , Terpenos/química , Técnicas de Química Analítica/métodos , Suplementos Nutricionais/análise , Doxorrubicina/química , Modelos Químicos , Conformação Molecular , Análise de Regressão , Temperatura
5.
Anal Bioanal Chem ; 389(1): 179-96, 2007 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17619180

RESUMO

A suite of three ginkgo-containing dietary supplement Standard Reference Materials (SRMs) has been issued by the National Institute of Standards and Technology (NIST) with certified values for flavonoid aglycones, ginkgolides, bilobalide, and selected toxic trace elements. The materials represent a range of matrices (i.e., plant, extract, and finished product) that provide different analytical challenges. The constituents have been determined by at least two independent analytical methods with measurements performed by NIST and at least one collaborating laboratory. The methods utilized different extractions, chromatographic separations, modes of detection, and approaches to quantitation. The SRMs are primarily intended for method validation and for use as control materials to support the analysis of dietary supplements and related botanical materials.


Assuntos
Suplementos Nutricionais/análise , Suplementos Nutricionais/normas , Ginkgo biloba/química , Arsênio/análise , Arsênio/toxicidade , Cromatografia Líquida , Flavonoides/química , Ginkgolídeos/química , Lactonas/química , Metais Pesados/análise , Metais Pesados/toxicidade , Estrutura Molecular , Padrões de Referência , Espectrometria de Massas por Ionização por Electrospray , Terpenos/química
6.
J AOAC Int ; 90(3): 647-58, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17580616

RESUMO

A single-laboratory validation was completed for a method to determine total terpene lactones in Ginkgo biloba products. The method determines terpene lactones on the basis of the main terpene lactones (Bilobalide, Ginkgolide A, Ginkgolide B, Ginkgolide C, and Ginkgolide J) by high-performance liquid chromatography with evaporative light-scattering detection after extraction. Nine matrixes were chosen for study, including crude leaf material, standardized dry powder extract, single- and multiple-entity finished products, and alcohol and glycerin tinctures. The sample purification with prepacked columns allows selective extraction of the terpene lactones with no interferences from any matrix under study. A Youden ruggedness trial testing 7 instrumental and preparation factors with the potential to affect quantitative results showed that 2 factors (volume of the column elution solvent and pH of the diluent) were the most important parameters to control during sample preparation. The method performed well in terms of precision; 4 matrixes tested in triplicate over a 3-day period showed an overall repeatability relative standard deviation (RSD) of about 3%. HorRat values were within the limits for performance acceptability, ranging from 0.5 to 1.0. Analysis of variance testing at a = 0.05 showed no significant differences among the within-or between-group sources of variation, although comparison of within-day, between-day, and total precision showed that most of the RSD came from within-day determinations except those for the Ginkgo dry extract (Gb-SLV-2). Accuracy testing at 4 concentration levels of terpene lactones obtained by spiking a negative control matrix at approximately 300, 750, 1500, and 2250 microg/mL gave recoveries of about 91% for the 300 microg/mL level, about 98% for the 750 microg/mL level, about 99% for the 1500 microg/mL level, and 97% for the 2250 microg/mL level with an overall recovery of 96% and an RSD of 3.2%.


Assuntos
Técnicas de Química Analítica/métodos , Cromatografia Líquida de Alta Pressão/métodos , Suplementos Nutricionais/análise , Ginkgo biloba/metabolismo , Calibragem , Ginkgolídeos/análise , Concentração de Íons de Hidrogênio , Lactonas/análise , Lactonas/química , Luz , Reprodutibilidade dos Testes , Espalhamento de Radiação , Terpenos/química
7.
J AOAC Int ; 90(1): 43-53, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17373435

RESUMO

An interlaboratory study was conducted for evaluation of a method to determine the flavonol aglycones quercetin, kaempferol, and isorhamnetin in Ginkgo biloba products. The method calculates total glycosides based on these aglycones formed after acid hydrolysis. Twelve matrixes were chosen for study by 12 collaborating laboratories in 2 countries. Test materials included crude leaf material, standardized dry powder extract, single and multiple entity finished products, ethanol and glycerol tinctures, and National Institute of Standards and Technology (NIST) standard reference materials (SRMs). Results from 11 laboratories were used for the final calculations. Eight of the 12 matrixes evaluated produced acceptable results for total flavonol glycosides, with HorRat scores ranging from 1.31 to 2.05; repeatability relative standard deviations (RSDr) from 1.46 to 4.14; and reproducibility relative standard deviations (RSDR) from 4.67 to 9.69. These 8 matrixes consisted primarily of simple dosage forms (e.g., dry powder extracts, crude leaf samples, liquid extracts, and SRMs) and a single tablet product (Ginkgo Awareness). Four additional matrixes, consisting of 3 tablets and 1 soft gel product (Ginkgold, Ginkoba, Ginkogen, and Ginkgo Phytosome, respectively), showed greater total flavonol glycoside HorRat scores in comparison, ranging from 2.39 to 5.13, with RSDr values from 2.83 to 8.16, and RSDR values from 8.53 to 20.4. Based on the results presented here, the method is recommended for Official First Action for determination of total flavonol glycosides calculated from quercetin, kaempferol, and isorhamnetin in dry powder extracts, crude leaf material, liquid extracts, and a select finished product, Ginkgo Awareness.


Assuntos
Suplementos Nutricionais , Flavonóis/análise , Ginkgo biloba/química , Quempferóis/análise , Quercetina/análise , Calibragem , Cromatografia Líquida de Alta Pressão/métodos , Cromatografia Líquida/métodos , Laboratórios/normas , Folhas de Planta/química , Padrões de Referência , Seringas
8.
Int Immunopharmacol ; 6(7): 1214-21, 2006 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16714226

RESUMO

Alkylamides present in Echinacea species have reported immunomodulatory actions, yet their direct effects on T lymphocytes, key mediators of antiviral immunity, are poorly understood. We hypothesized that constituents present in ethanolic extracts of Echinacea species exert direct immunomodulatory effects on human Jurkat T cells. Modulation of IL-2 production by submaximally stimulated Jurkat cells was determined in response to treatment with extracts prepared from dried aerial parts of Echinacea purpurea. Cells were treated with the extracts, with alkylamides or caffeic acid derivatives isolated from Echinacea species, or with corresponding ethanol vehicle, in the absence or presence of phytohemagglutinin and phorbal ester. E. purpurea extracted in a solvent mixture of 95:5 ethanol/water dose-dependently inhibited IL-2 production. This IL-2 inhibitory activity correlated with the presence of alkylamides but not caffeic acid derivatives, as determined by high performance liquid chromatography/electrospray ionization-mass spectrometry analysis. Simultaneous measurement of secreted IL-2 by ELISA and cell viability by the XTT assay showed that the 95:5 ethanol/water extract of E. purpurea was both IL-2 suppressive and cytotoxic at 50 and 100 microg/mL. Lower concentrations from 6.25 to 25 microg/mL significantly decreased IL-2 production but not cell viability. Alkylamides at concentrations found in a 50 microg/mL extract decreased IL-2 production by approximately 50%. Two Echinacea-derived alkylamides significantly depressed IL-2 production but not cell viability in a dose-dependent manner. Thus, alkylamides present in E. purpurea suppress the ability of activated Jurkat T cells to produce IL-2 independently of direct, cytotoxic effects.


Assuntos
Amidas/farmacologia , Echinacea/química , Interleucina-2/imunologia , Ácidos Cafeicos/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Humanos , Células Jurkat , Mitógenos , Fito-Hemaglutininas , Extratos Vegetais/farmacologia , Acetato de Tetradecanoilforbol
9.
J AOAC Int ; 88(3): 692-702, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-16001841

RESUMO

A single laboratory validation (SLV) was completed for a method to determine the flavonol aglycones quercetin, kaempferol, and isorhamnetin in Ginkgo biloba products. The method calculates total glycosides based on these aglycones formed following acid hydrolysis. Nine matrixes were chosen for the study, including crude leaf material, standardized dry powder extract, single and multiple entity finished products, and ethanol and glycerol tinctures. For the 9 matrixes evaluated as part of this SLV, the method appeared to be selective and specific, with no observed interferences. The simplified 60 min oven heating hydrolysis procedure was effective for each of the matrixes studied, with no apparent or consistent differences between 60, 75, and 90 min at 90 degrees C. A Youden ruggedness trial testing 7 factors with the potential to affect quantitative results showed that 2 factors (volume hydrolyzed and test sample extraction/hydrolysis weight) were the most important parameters for control during sample preparation. The method performed well in terms of precision, with 4 matrixes tested in triplicate over a 3-day period showing an overall repeatability (relative standard deviation, RSD) of 2.3%. Analysis of variance testing at alpha = 0.05 showed no significant differences among the within- or between-group sources of variation, although comparisons of within-day (Sw), between-day (Sb), and total (St) precision showed that a majority of the standard deviation came from within-day determinations for all matrixes. Accuracy testing at 2 levels (approximately 30 and 90% of the determined concentrations in standardized dry powder extract) from 2 complex negative control matrixes showed an overall 96% recovery and RSD of 1.0% for the high spike, and 94% recovery and RSD of 2.5% for the low spike. HorRat scores were within the limits for performance acceptability, ranging from 0.4 to 1.3. Based on the performance results presented herein, it is recommended that this method progress to the collaborative laboratory trial.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Flavonóis/química , Ginkgo biloba/química , Ginkgo biloba/metabolismo , Quempferóis/análise , Quercetina/análise , Calibragem , Técnicas de Química Analítica/métodos , Cromatografia Líquida de Alta Pressão/instrumentação , Etanol/química , Flavonóis/análise , Glicerol/química , Hidrólise , Modelos Químicos , Extratos Vegetais/análise , Folhas de Planta/metabolismo , Pós , Reprodutibilidade dos Testes , Temperatura , Fatores de Tempo
10.
J AOAC Int ; 88(6): 1613-20, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-16526440

RESUMO

We report here a liquid chromatography (LC) method with inline ultraviolet/evaporative light scattering (UV/ELS) detection for the simultaneous quantification of the terpenelactones and flavonol aglycones in a single sample of hydrolyzed Ginkgo biloba extract (GBE). The sample is hydrolyzed by a rapid and convenient oven heating method for 1 h at 90 degrees C with 10% hydrochloric acid. The 1 h hydrolysis was found to be equivalent to the 2.25 h reflux treatment for dry powder extract, where total flavonol glycosides were 28.4 and 28.1%, respectively. Acceptable precision was achieved for total terpenelactones [relative standard deviation (RSD) = 4.8%] by ELS detection, and total flavonol aglycones (RSD = 2.3%) by UV detection. The analytical range was 1.5 to 7.3% (w/w) for the individual terpenelactones (ELS) and 2.5 to 15.0% (w/w) for the individual glycosides (UV) calculated from the aglycones quercetin, kaempferol, and isorhamnetin. This improved method allows for the first time high throughput sample preparation coupled with the quantification of the predominant compounds generally used for quality control of GBE in a single assay.


Assuntos
Cromatografia Líquida/métodos , Flavonóis/análise , Ginkgo biloba/metabolismo , Lactonas/análise , Extratos Vegetais/análise , Terpenos/análise , Cromatografia , Glicosídeos/análise , Glicosídeos/química , Temperatura Alta , Ácido Clorídrico/análise , Hidrólise , Íons , Quempferóis/análise , Luz , Modelos Químicos , Preparações Farmacêuticas/química , Controle de Qualidade , Quercetina/análise , Reprodutibilidade dos Testes , Espalhamento de Radiação , Espectrofotometria Ultravioleta , Temperatura , Fatores de Tempo , Raios Ultravioleta
11.
J AOAC Int ; 87(5): 1049-57, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15493660

RESUMO

Preparations from comfrey (Symphytum officinale and S. x uplandicum) root and leaf contain varying levels of the hepatotoxic pyrrolizidine alkaloids (PAs). Reference compounds for comfrey are not commercially available, and there is currently no rapid extraction or analytical method capable of determining low levels in raw materials or as adulterants in commercially available extracts. A solid-phase extraction (SPE) method was developed using an Ergosil cleanup column that specifically binds the PAs. With this method, powdered comfrey root was extracted by sonication and shaking with basic chloroform. The extract was applied to the cleanup column under vacuum, washed with 2 mL acetone-chloroform (8 + 2, v/v) followed by 2 mL petroleum ether to remove excess chloroform. The column was dried under vacuum, and the PAs were eluted with 2 successive 1 mL aliquots methanol. Percent recoveries of the PAs following Ergosil SPE had an overall average of 96.8%, with RSD of 3.8% over a range of 1.0 to 25.0 g extracted in 100 mL. Average precision of the method (n = 3 over 4 extraction concentrations) gave an overall RSD of 6.0% for the 5 alkaloids, with a range of 0.8% (5 g in 100 mL) to 11.2% (25 g in 100 mL). Recovery optimization testing showed that 1.0 g comfrey root extracted in 100 mL yielded the greatest recovery (% dry weight) of the PAs, with an extraction efficiency and accuracy of 94.2%, and RSD of 1.7% (n = 9). The unique properties of the Ergosil cleanup column provide rapid sample cleanup, volume reduction, and concentration of PAs from comfrey extracts, and allow the eluant to be analyzed directly by traditional chromatographic methods.


Assuntos
Confrei/química , Raízes de Plantas/química , Alcaloides de Pirrolizidina/análise , Cromatografia Líquida , Espectrometria de Massas , Alcaloides de Pirrolizidina/isolamento & purificação , Espectrofotometria Ultravioleta
12.
Planta Med ; 69(1): 50-5, 2003 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-12567279

RESUMO

The effects of acute periods of drought stress on dry weight, and alkamide and phenolic acid content in purple coneflower [Echinacea purpurea (L.) Moench, Asteraceae] roots are described. Plants subjected to brief drought stress periods for two seasons during the initial flowering stage (D-F2) produced fall-harvested roots with significantly greater cichoric acid concentration (mg/g) than corresponding well-watered controls of the same age (C-2). Total alkamide, including the tetraenoic acid isomers, and chlorogenic acid concentrations from fall-harvested roots were largely unaffected by drought stress, regardless of when the stress occurred developmentally. The alkamide concentration in three-year roots was significantly less than that in two-year roots, with an average decrease of 50.5 %. Conversely, total phenolic acids increased an average of 67.1 % for all treatments from two to three years of age. Root dry weight increased significantly by an average of 70.0 % for all drought-stressed plants from two to three years of age, compared to an increase of 35.2 % for well-watered controls. The results suggest that controlled drought stress can stimulate increased root dry weight and root cichoric acid content, and that root age is the predominant factor determining overall phytochemical content variation.


Assuntos
Alcinos/metabolismo , Amidas/metabolismo , Echinacea/metabolismo , Hidroxibenzoatos/metabolismo , Raízes de Plantas/metabolismo , Echinacea/química , Echinacea/fisiologia , Raízes de Plantas/química , Raízes de Plantas/fisiologia , Fatores de Tempo , Água
13.
Planta Med ; 69(11): 1024-30, 2003 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-14735441

RESUMO

The phytochemistry and dry weight of cultivated St. John's wort are significantly influenced by acute drought stress and time of harvest. In this study, plants subjected to brief drought stress during both flower and seed development periods exhibited increased concentrations in 8 of the 10 phytochemicals examined in this study, including hypericin, pseudohypericin, chlorogenic acid, rutin, hyperoside, isoquercitrin, quercitrin, and quercetin. Increases ranged from 5% to 36% (hyperoside and rutin, respectively). Conversely, the concentrations of hyperforin and adhyperforin in flowers were decreased by an average of 10% in drought-stressed plants as compared to well-watered control plants. Acute drought stress decreased flower dry weight significantly during both drydown periods, although vegetative parameters (height, leaf dry weight and stem dry weight) were not adversely affected. While acute drought stress significantly altered the chemical yield in the leaves and flowers (phytochemical content x harvested dry weight), the time of harvest was the predominant factor determining phytochemical concentration in the organs of H. perforatum.


Assuntos
Adaptação Fisiológica , Hypericum/fisiologia , Fitoterapia , Estresse Fisiológico , Agricultura , Desastres , Flores/química , Flores/fisiologia , Humanos , Hypericum/química , Folhas de Planta/química , Folhas de Planta/fisiologia
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