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1.
PLoS One ; 19(7): e0299965, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39018291

RESUMEN

The challenges of the COVID-19 pandemic have highlighted an increasing clinical demand for safe and effective treatment options against an overzealous immune defence response, also known as the "cytokine storm". Andrographolide is a naturally derived bioactive compound with promising anti-inflammatory activity in many clinical studies. However, its cytokine-inhibiting activity, in direct comparison to commonly used nonsteroidal anti-inflammatory drugs (NSAIDs), has not been extensively investigated in existing literature. The anti-inflammatory activities of andrographolide and common NSAIDs, such as diclofenac, aspirin, paracetamol and ibuprofen were measured on lipopolysaccharide (LPS) and interferon-γ induced RAW264.7 cells. The levels of PGE2, nitric oxide (NO), TNF-α & LPS-induced release of pro-inflammatory cytokines on differentiated human macrophage THP-1 cells were measured against increasing concentrations of andrographolide and aforementioned NSAIDs. The associated mechanistic pathway was examined on NFκB using flow cytometry on the human endothelial-leukocyte adhesion molecule (ELAM9) (E-selectin) transfected RAW264.7 cells with green fluorescent protein (GFP). Andrographolide exhibited broad and potent anti-inflammatory and cytokine-inhibiting activity in both cell lines by inhibiting the release of IL-6, TNF-α and IFN-γ, which are known to play a key role in the etiology of cytokine storm and the pathogenesis of inflammation. In comparison, the tested NSAIDs demonstrated weak or no activity against proinflammatory mediators except for PGE2, where the activity of andrographolide (IC50 = 8.8 µM, 95% CI = 7.4 to 10.4 µM) was comparable to that of paracetamol (IC50 = 7.73 µM, 95% CI = 6.14 to 9.73 µM). The anti-inflammatory action of andrographolide was associated with its potent downregulation of NFκB. The wide-spectrum anti-inflammatory activity of andrographolide demonstrates its therapeutic potential against cytokine storms as an alternative to NSAIDs.


Asunto(s)
Antiinflamatorios no Esteroideos , Citocinas , Diterpenos , Diterpenos/farmacología , Animales , Ratones , Humanos , Antiinflamatorios no Esteroideos/farmacología , Células RAW 264.7 , Citocinas/metabolismo , Óxido Nítrico/metabolismo , Antiinflamatorios/farmacología , Síndrome de Liberación de Citoquinas/tratamiento farmacológico , FN-kappa B/metabolismo , Dinoprostona/metabolismo , Lipopolisacáridos/farmacología , Células THP-1 , Macrófagos/efectos de los fármacos , Macrófagos/metabolismo , Factor de Necrosis Tumoral alfa/metabolismo , Ibuprofeno/farmacología , Ibuprofeno/uso terapéutico , Interferón gamma/metabolismo , Selectina E/metabolismo
2.
Heliyon ; 10(11): e31672, 2024 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-38868030

RESUMEN

Amauroderma rugosum (Blume and T. Nees) Torrend is a traditionally well-known mushroom that is used for the treatment of cancer. In order to evaluate the pharmacological activities of A. rugosum polysaccharides, the mushroom powder was subjected to hot water extraction and pure polysaccharides (ARPs) were isolated by gel-filtration method. Three important APRs called ARP-1, ARP-2 and ARP-5 were identified with average molecular weights of 1494, 450, and 7 kDa respectively. Their antioxidant abilities were estimated by examining free radical scavenging potential against 2,2'-azino-bis (3-ethylbenzothiazoline-6-sulphonic acid radical (ABTS●+), 2,2-diphenyl-1-picrylhydrazyl radical (DPPH●), and hydroxyl radical. Immunomodulatory potentials of these ARPs were determined using murine macrophage cells. These polysaccharides exhibited high antioxidant abilities and stimulated mouse macrophages leading to the generation of tumour necrosis factor-α (TNF-α) and interleukin-6 (IL-6). Excellent activities were displayed by ARP-1 and APR-2. Gas chromatography and spectroscopic (FT-IR and NMR) methods were employed in order to carry out their structural characterisation. The two high molecular weight ARPs (ARP-1 and ARP-2) displayed ß-(1 â†’ 3)-D-glucan backbone structure with branching of ß-(1 â†’ 6)-d-glucopyranosyl. These observations suggest high potential of ARPs for immunotherapeutic applications.

3.
Biotechnol Genet Eng Rev ; : 1-22, 2023 Apr 17.
Artículo en Inglés | MEDLINE | ID: mdl-37066895

RESUMEN

Leonurus japonicus Houtt is an important anti-skin pigmentation herb used in traditional Chinese medicine. However, the molecular basis for this activity is complex and not fully understood. In this study, water and ethanol extracts and polysaccharide extract from L. japonicus (LJPs) were analyzed by LC-MS/MS and HPLC-DAD separately. Cytotoxicity was analyzed by using CCK-8, antioxidant activity using flow cytometer, anti-MMPs, anti-tyrosinase and signalling pathway analysis using Western blotting to investigate their anti-melanogenesis function. The results showed that the water and ethanol extracts contained alkaloids, flavonoids, and phenolic acids. The LJPs mainly contain glucose, fucose, glucuronic acid, mannose, threonine and arginine, and structure characterization by FITR analyses indicated that LJPs have ß- or α-D-glycosidic bonds and contain pyranose rings. The L. japonicus extracts displayed high cell viability at their maximum concentration. The water extract and polysaccharides significantly reduced lipopolysaccharide (LPS)-induced intracellular reactive oxygen species (ROS) content and exhibited a cytoprotective role. Also, these extracts displayed higher matrix metalloproteinase-2 (anti-MMP-2), anti-MMP-9 and anti-tyrosinase activities. Furthermore, the polysaccharides displayed significantly greater inhibitory effect on intracellular ROS and tyrosinase protein expression than α-arbutin and ursolic acid used for the clinical treatment of skin pigmentation. This study also investigated the polysaccharide inhibition of melanin synthesis by repressing the expression of melanocytic lineage-specific transcription factor (MITF) and melanogenic enzymes via modulation of the phosphoinositide 3-kinase (PI3K-Akt-mTOR) and ß-catenin pathways. The overall results indicate that L. japonicus is a promising candidate for anti-pigmentation treatment.

4.
Artículo en Inglés | MEDLINE | ID: mdl-35958917

RESUMEN

This study evaluates the in vitro antioxidant and immunomodulation activities of essential oils isolated from an anti-upper respiratory tract infection (URTI) formulation with a view to their therapeutic potential. The chemical components of the essential oil were analysed by gas chromatography-mass spectrometry (GC-MS). The antioxidative activity of the oils was investigated with regard to their ability to scavenge DPPH●, ABTS●+, and hydroxyl free radical (•OH). Their immunostimulatory activities were determined using murine macrophage cells. The main components of the oil with pharmacological and biological activities include 1,8-eucalyptol (42.9%), patchouli alcohol (19.9%), trans-erinolide (9.2%), and guaiacol (5%). The oils displayed high DPPH, ABTS, and hydroxyl radical scavenging activities and anti-inflammatory activities by reducing tumour necrosis factor-α (TNF-α) and interleukin-6 (IL-6) production. The results indicate that essential oils have the potential to be used in products for anti-URTI treatment.

5.
Molecules ; 27(11)2022 Jun 06.
Artículo en Inglés | MEDLINE | ID: mdl-35684579

RESUMEN

Arimisia annua L. is an important anticancer herb used in traditional Chinese medicine. The molecular basis underpinning the anticancer activity is complex and not fully understood, but the herbal polysaccharides, broadly recognised as having immunomodulatory, antioxidant and anticancer activities, are potential key active agents. To examine the functions of polysaccharides from A. annua, their immunomodulatory and antioxidant potentials were evaluated, as well as their structural characterization. The water-soluble polysaccharides (AAPs) were fractionated using size-exclusion chromatography to obtain three dominant fractions, AAP-1, AAP-2 and AAP-3, having molecular masses centered around 1684, 455 and 5.8kDa, respectively. The antioxidant potentials of the isolated polysaccharides were evaluated by measuring radical scavenging activities against DPPH● (2,2-diphenyl-1-picrylhydrazyl radical), ABTS●+ (2,2'-azino-bis (3-ethylbenzothiazoline-6-sulphonic acid radical ion), and the OH● (hydroxyl radical). AAP-1 displayed high antioxidant activities against these radicals, which were 68%, 73% and 78%, respectively. AAP-2 displayed lower scavenging activities than the other two fractions. Immunostimulatory activities of AAPs were measured using mouse macrophages. The three polysaccharide fractions displayed significant antioxidant activities and stimulated the production of tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6). AAP-1 showed significant immunostimulatory activity (16-fold increase in the production of IL-6 compared to the control and 13-fold increase in the production of TNF-α) with low toxicity (>60% cell viability at 125 µg/mL concentration). Preliminary structural characterization of the AAPs was carried out using gas chromatography (GC) and FTIR techniques. The results indicate that AAP-1 and AAP-2 are pyranose-containing polysaccharides with ß-linkages, and AAP-3 is a ß-fructofuranoside. The results suggest that these polysaccharides are potential candidates for immunotherapy and cancer treatment.


Asunto(s)
Antioxidantes , Artemisia annua , Animales , Antioxidantes/química , Artemisia annua/química , Interleucina-6 , Ratones , Polisacáridos/química , Factor de Necrosis Tumoral alfa
6.
Plants (Basel) ; 8(12)2019 Dec 13.
Artículo en Inglés | MEDLINE | ID: mdl-31847243

RESUMEN

Lycium (also known as Goji berry) is used in traditional Chinese medicine (TCM) with claimed benefits, including eye and liver protection, immune system fortification and blood glucose control. The commercially available product comes from either the L. barbarum or L. chinense species, with the former dominating the marketplace due to its better taste profile. The main objective of this study was to develop a validated LC-ESI-MS/MS method to quantify multiple key bio-active analytes in commercially available Lycium berries and to qualitatively assess these samples using a principal component analysis (PCA). A LC-ESI-MS/MS method for the quantitation of seven analytes selected using the Herbal Chemical Marker Ranking System (Herb MaRS) was developed. The Herb MaRS ranking system considered bioavailability, bioactivity and physiological action of each target analyte, its intended use and the commercial availability of an analytical standard. After method optimization combining high resolving power with selective detection, seven analytes were quantified and the Lycium samples were quantitatively profiled. Chromatographic spectra were also obtained using longer run-time LC-UV and GC-MS methods in order to qualitatively assess the samples using a principal component analysis (PCA). The result of the method validation procedure was a 15.5 min LC-ESI-MS/MS method developed for the quantification of seven analytes in commercial Lycium samples. Wide variation in analyte concentration was observed with the following results (analyte range in mg/g): rutin, 16.1-49.2; narcissin, 0.37-1.65; nictoflorin, 0.26-0.78; coumaric acid, 6.84-12.2; scopoletin, 0.33-2.61; caffeic acid, 0.08-0.32; chlorogenic acid, 1.1-9.12. The quantitative results for the L. barbarum and L. chinense species samples indicate that they cannot be differentiated based on the bio-actives tested. A qualitative assessment using PCA generated from un-targeted LC-UV and GC-MS phytochemical spectra led to the same conclusion. The un-targeted quantitative and qualitative phytochemical profiling indicates that commercial L. barbarum and L. chinense cannot be distinguished using chemical analytical methods. Genetic fingerprinting and pharmacological testing may be needed to ensure the efficacy of commercial Lycium in order to validate label claims.

7.
Molecules ; 24(8)2019 Apr 17.
Artículo en Inglés | MEDLINE | ID: mdl-30999707

RESUMEN

Background-The quality control (QC) for commercial herbal formulations is sparse due to a lack of well-developed HPLC-ESI-MS/MS methods. Objective-This study reports the quantification of nine selected analytes for a commercial eight-herb formulation known as Qi Ju Di Huang Wan (QJDHW) used to relieve hypertension. Methods-An HPLC-ESI/MS method for the quantitation of analytes selected using the Herbal Chemical Marker Ranking System (Herb MaRS) was developed. The Herb MaRS ranking system which takes into account bioavailability, bioactivity, and physiological action related to its intended use and the commercial availability of the standard. After a method optimization, seven analytes were found to be ideal for quantitation. Results-The target analytes were identified using an electrospray ionization-tandem MS molecular breakdown comparison between the herbal peak and the commercial standard. The quantitative aspect of analyte variability of eleven samples was studied using fold variation. The fold variation of selected analytes among eleven samples ranged from 1.5 to 28.9. The qualitative aspect of variability was studied using principal component analysis (PCA) and hierarchical cluster analysis (HCA). Conclusions-There is a great degree of chemical variability in herbal formulations which are due to raw material harvesting times, storage techniques, and plant subspecies variability. Highlights-Commercial QJDHW formulations need to be standardised using HPLC-ESI-MS/MS to ensure better product quality control (QC) and product efficacy for the consumer.


Asunto(s)
Antihipertensivos/análisis , Medicamentos Herbarios Chinos/análisis , Hipertensión/tratamiento farmacológico , Control de Calidad , Astragalus propinquus , Cromatografía Líquida de Alta Presión/métodos , Humanos , Espectrometría de Masas en Tándem/métodos
8.
Molecules ; 24(6)2019 Mar 20.
Artículo en Inglés | MEDLINE | ID: mdl-30897753

RESUMEN

The Naoxinqing (NXQ) tablet is a standardised proprietary herbal product containing an extract of persimmon leaves (Diospyros kaki) for the management of cardio- and cerebrovascular diseases. Although previous reports suggested that the efficacy of NXQ is at least partly mediated by its anti-oxidative property, the anti-oxidative effect of the major components of NXQ has not been studied systematically. For quality control purposes, only analytical methods limited to 3 marker analytes have been reported, the extent to which the other components affect efficacy has not been explored. In this study, we developed an ultra-performance liquid chromatography-tandem mass spectrometry (UPLC MS/MS) method for the identification of seven analytes (kaempferol-3-O-glucoside (astragalin), quercetin-3-O-galactoside (hypericin), quercetin-3-O-glucoside (isoquercitin), kaempferol, 3,4-dihydroxybenzoic acid (protocatechuic acid), and furan-2-carboxylic acid (pyromucic acid) and quercetin) in the NXQ. This is the first method reported and validated for the quantification of the seven major secondary metabolites in NXQ. The results for the quantified analytes were then compared in 15 different batches of NXQ. The variation observed in the seven components highlights the need to quantify key bioactive components to ensure product consistency. Radical scavenging activity and abundance was used to rank the analytes. The anti-oxidative effects of NXQ were examined using cultured human vascular endothelial cells (EA.hy926). Corrected 2,2-di(4-tert-octylphenyl)-1-picrylhydrazyl (DPPH) activity results revealed that quercetin and kaempferol have the strongest anti-oxidant capacity in the extract. Both quercetin and kaempferol significantly inhibited the hydrogen peroxide (H2O2)-induced EA.hy926 cell injury and intracellular reactive oxygen species (ROS) generation. In conclusion, we established and validated an UPLC-MS/MC method for the analysis of major bioactive components in the NXQ and demonstrated that its anti-oxidative property may play a critical role in cerebrovascular protection.


Asunto(s)
Diospyros/química , Medicamentos Herbarios Chinos/química , Extractos Vegetales/química , Hojas de la Planta/química , Antracenos , Línea Celular , Cromatografía Líquida de Alta Presión , Humanos , Hidroxibenzoatos/química , Quempferoles/química , Perileno/análogos & derivados , Perileno/química , Quercetina/análogos & derivados , Quercetina/química , Especies Reactivas de Oxígeno , Espectrometría de Masas en Tándem
9.
J AOAC Int ; 2016 Mar 24.
Artículo en Inglés | MEDLINE | ID: mdl-27013463

RESUMEN

There is a need for increased QC of complex herbal medicine formulations to ensure product consistency, efficacy, and safety. This study reports an HPLC with photodiode array and electrospray ionization-tandem MS method for quantifying selected analytes in a seven-herb formulation. Fourteen analytes were selected for quantification based on the criteria available from the Herbal Chemical Marker Ranking System, which takes into account the bioavailability, reported bioactivity, and physiological action related to its intended use, as well as commercial availability of the standard. After optimizing the columns and chromatographic conditions, 13 of the 14 analytes were able to be determined in one run, with the remaining analyte analyzed on its own. The method was successfully applied to two different extracts of the formulation, demonstrating an application for the QC of a complex herbal mixture with respect to their chemical characteristics.

10.
BMC Complement Altern Med ; 15: 18, 2015 Feb 07.
Artículo en Inglés | MEDLINE | ID: mdl-25888070

RESUMEN

BACKGROUND: The anti-inflammatory activity of Andrographis paniculata (Acanthaceae), a traditional medicine widely used in Asia, is commonly attributed to andrographolide, its main secondary metabolite. Commercial A. paniculata extracts are standardised to andrographolide content. We undertook the present study to investigate 1) how selective enrichment of andrographolide in commercial A. paniculata extracts affects the variability of non-standardised phytochemical components and 2) if variability in the non-standardised components of the extract affects the pharmacological activity of andrographolide itself. METHODS: We characterized 12 commercial, standardised (≥30% andrographolide) batches of A. paniculata extracts from India by HPLC profiling. We determined the antioxidant capacity of the extracts using 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical scavenging, oxygen radical antioxidant capacity (ORAC) and a Folin-Ciocalteu (FC) antioxidant assays. Their anti-inflammatory activity was assessed by assaying their inhibitory effect on the release of tumor necrosis factor alpha (TNF-α) in the human monocytic cell line THP-1. RESULTS: The andrographolide content in the samples was close to the claimed value (32.2 ± 2.1%, range 27.5 to 35.9%). Twenty-one non-standardised constituents exhibited more than 2-fold variation in HPLC peak intensities in the tested batches. The chlorogenic acid content of the batches varied more than 30-fold. The DPPH free radical scavenging activity varied ~3-fold, the ORAC and FC antioxidant capacity varied ~1.5 fold among batches. In contrast, the TNF-α inhibitory activity of the extracts exhibited little variation and comparison with pure andrographolide indicated that it was mostly due to their andrographolide content. CONCLUSIONS: Standardised A. paniculata extracts contained the claimed amount of andrographolide but exhibited considerable phytochemical background variation. DPPH radical scavenging activity of the extracts was mostly due to the flavonoid/phenlycarboxylic acid compounds in the extracts. The inhibitory effect of andrographolide on the release of TNF-α was little affected by the quantitative variation of the non-standardised constituents.


Asunto(s)
Andrographis/química , Antiinflamatorios/farmacología , Antioxidantes/farmacología , Diterpenos/farmacología , Extractos Vegetales/farmacología , Factor de Necrosis Tumoral alfa/metabolismo , Compuestos de Bifenilo/metabolismo , Ácido Clorogénico/análisis , Ácido Clorogénico/farmacología , Cromatografía Líquida de Alta Presión , Diterpenos/análisis , Flavonoides/análisis , Flavonoides/farmacología , Humanos , Técnicas In Vitro , India , Monocitos/efectos de los fármacos , Monocitos/metabolismo , Picratos/metabolismo , Extractos Vegetales/normas
11.
BMC Genomics ; 14: 445, 2013 Jul 04.
Artículo en Inglés | MEDLINE | ID: mdl-23826764

RESUMEN

BACKGROUND: Pattern-oriented chemical profiling is increasingly being used to characterize the phytochemical composition of herbal medicines for quality control purposes. Ideally, a fingerprint of the biological effects should complement the chemical fingerprint. For ethical and practical reasons it is not possible to test each herbal extract in laboratory animals or humans. What is needed is a test system consisting of an organism with relevant biology and complexity that can serve as a surrogate in vitro system. The purpose of this study was to test the hypothesis that the Saccharomyces cerevisiae transcriptome might be used as an indicator of phytochemical variation of closely-related yet distinctly different extracts prepared from a single species of a phytogeographically widely distributed medicinal plant. We combined phytochemical profiling using chromatographic methods (HPTLC, HPLC-PDA-MS/MS) and gene expression studies using Affymetrix Yeast 2.0 gene chip with principal component analysis and k-nearest neighbor clustering analysis to test this hypothesis using extracts prepared from the phytogeographically widely distributed medicinal plant Equisetum arvense as a test case. RESULTS: We found that the Equisetum arvense extracts exhibited qualitative and quantitative differences in their phytochemical composition grouped along their phytogeographical origin. Exposure of yeast to the extracts led to changes in gene expression that reflected both the similarities and differences in the phytochemical composition of the extracts. The Equisetum arvense extracts elicited changes in the expression of genes involved in mRNA translation, drug transport, metabolism of energy reserves, phospholipid metabolism, and the cellular stress response. CONCLUSIONS: Our data show that functional genomics in S. cerevisiae may be developed as a sensitive bioassay for the scientific investigation of the interplay between phytochemical composition and transcriptional effects of complex mixtures of chemical compounds. S. cerevisiae transcriptomics may also be developed for testing of mixtures of conventional drugs ("polypills") to discover novel antagonistic or synergistic effects of those drug combinations.


Asunto(s)
Equisetum/química , Extractos Vegetales/química , Extractos Vegetales/farmacología , Saccharomyces cerevisiae/efectos de los fármacos , Saccharomyces cerevisiae/genética , Transcriptoma/efectos de los fármacos , Américas , China , Bases de Datos Genéticas , Europa (Continente) , Depuradores de Radicales Libres/química , Depuradores de Radicales Libres/farmacología , India , Análisis de Secuencia por Matrices de Oligonucleótidos
12.
Int J Med Mushrooms ; 15(3): 251-66, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23662613

RESUMEN

A number of mushrooms are known to possess pharmacological activities. In this study, the phenolic and flavonoid contents of extracts of exo- and endopolysaccharide fractions obtained from submerged mycelia cultures of 7 edible or medicinal mushroom species, as well as their antioxidant and immunomodulatory properties, were evaluated. The exo- and endopolysaccharide yields were 0.576-1.950 and 0.438-0.933 g/L, respectively. The sugar and protein contents of these fractions were analyzed and contained predominantly sugars (52.3-87.6%). The exo- and endopolysaccharide fractions contained appreciable amounts of phenolics and flavonoids. The highest flavonoid contents were found in Cryptosporus volvatus (349.6 mg/g), followed by Cordyceps militaris (312.6 mg/g). The antioxidant activities were evaluated by 4 assays: biological assay using Saccharomyces cerevisiae, DPPH radical scavenging activity, chelating ability for ferrous ions and ferric reducing antioxidant power. The mycelia polysaccharide fractions had more ferric reducing antioxidant power than other antioxidant activities. Both exo- and endo polysaccharides of C. volvatus inhibited production of the T lymphocyte Th1 cytokines interferon (IFN)-γ and interleukin (IL)-2, the Th2 cytokines IL-4 and IL-5, and macrophage enzyme activity. Although those from C. militaris had similar inhibitory effects on cytokine production, the exopolysaccharides stimulated macrophage enzyme activity. The other exopolysaccharides (Pleurotus citrinopileatus, P. australis, and P. pulmonarius) inhibited IFN-γ and IL-5 production, but they had varying effects on IL-2 and IL-4 production. Only 3 exopolysaccharides (P. pulmonarius, Tremella mesenterica, and Cordyceps sinensis) also stimulated macrophage enzyme activity to the same extent as lipopolysaccharides. All of them reduced IL-5 production, but those from T. mesenterica also inhibited IFN-γ, IL-2, and IL-4 production. Thus the polysaccharide fractions from the mushrooms studied have antioxidant activities and general immunomodulating effects in vitro.


Asunto(s)
Agaricales/química , Antioxidantes , Polisacáridos Fúngicos/farmacología , Factores Inmunológicos , Micelio/metabolismo , Animales , Células Cultivadas , Polisacáridos Fúngicos/química , Humanos , Leucocitos Mononucleares/efectos de los fármacos , Macrófagos/efectos de los fármacos , Ratones , Fenoles
13.
Nurse Educ Today ; 33(7): 729-33, 2013 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-23411392

RESUMEN

AIMS: To compare health and science students' demographic characteristics and learning approaches across different disciplines, and to examine the relationship between learning approaches and academic performance. BACKGROUND: While there is increasing recognition of a need to foster learning approaches that improve the quality of student learning, little is known about students' learning approaches across different disciplines, and their relationships with academic performance. DESIGN: Prospective, correlational design. METHODS: Using a survey design, a total of 919 first year health and science students studying in a university located in the western region of Sydney from the following disciplines were recruited to participate in the study - i) Nursing: n = 476, ii) Engineering: n = 75, iii) Medicine: n = 77, iv) Health Sciences: n = 204, and v) Medicinal Chemistry: n = 87. RESULTS: Although there was no statistically significant difference in the use of surface learning among the five discipline groups, there were wide variations in the use of deep learning approach. Furthermore, older students and those with English as an additional language were more likely to use deep learning approach. Controlling for hours spent in paid work during term-time and English language usage, both surface learning approach (ß = -0.13, p = 0.001) and deep learning approach (ß = 0.11, p = 0.009) emerged as independent and significant predictors of academic performance. CONCLUSIONS: Findings from this study provide further empirical evidence that underscore the importance for faculty to use teaching methods that foster deep instead of surface learning approaches, to improve the quality of student learning and academic performance.


Asunto(s)
Educación de Pregrado en Medicina/métodos , Evaluación Educacional , Empleos en Salud/educación , Ciencia/educación , Enseñanza/métodos , Adulto , Australia , Química Farmacéutica/educación , Ingeniería/educación , Femenino , Predicción , Humanos , Masculino , Estudios Prospectivos , Factores Socioeconómicos , Estadística como Asunto , Estudiantes de Medicina , Estudiantes de Enfermería , Adulto Joven
14.
Chin Med ; 7(1): 26, 2012 Nov 24.
Artículo en Inglés | MEDLINE | ID: mdl-23176585

RESUMEN

BACKGROUND: This study aims to determine the relationship between the antioxidant and anti-inflammatory activities of the thirteen herbs and two fungi extracts, and their total phenolic and flavonoid contents. METHODS: Antioxidant activities were evaluated by four assays: an antioxidant activity assay using Saccharomyces cerevisiae, a DPPH ((2, 2-diphenyl-1-picrylhydrazyl) assay to assess free radical scavenging, an assay assessing ferrous ions or iron (II) chelating ability, and a ferric reducing antioxidant power (FRAP) assay. Total phenolic and flavonoid contents were determined using the Folin-Ciocalteu and aluminium chloride methods, respectively. Anti-inflammatory activities were determined by measuring the inhibition of nitric oxide and TNF-α production in lipopolysaccharide- and interferon-γ-activated J774A.1 macrophages. Their cytotoxicities against macrophages were determined by MTT assay. RESULTS: A positive linear correlation between antioxidant activities and the total phenolic and flavonoid content of the plant extracts was found. The plant extracts with high phenolic and flavonoid content also exhibited significant anti-inflammatory activity with good cell viability. CONCLUSION: The selected herbs could be a rich source of antioxidants and free radical scavenging compounds. The levels of phenolic and flavonoid compounds were correlated with the antioxidant and anti-inflammatory activities of the extracts from the herbs.

15.
Methods Mol Biol ; 862: 181-200, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22419498

RESUMEN

The GenBank(®) database is perhaps one of the most important repositories of genetic information. A researcher working in the field of genomic authentication must therefore be equipped with the skills needed to competently access the required information from this database whilst ultimately contributing their own data to it. This chapter presents a practical guide to using GenBank(®) to search for sequences, search and align unknown sequences using BLAST, and uploading and maintaining your own sequences. This chapter also details some other software helpful in sequence manipulation.


Asunto(s)
Bases de Datos de Ácidos Nucleicos , Genoma
16.
J AOAC Int ; 93(1): 116-22, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-20334173

RESUMEN

A GC method was developed for the identification and quantitation of eight sympathomimetic amines in urine, i.e., amphetamine, methamphetamine, mephentermine, ephedrine, pseudoephedrine, methylenedioxyamphetamine, methylenedioxymethamphetamine, and methylenedioxyethylamphetamine. Methoxyphenamine was used as the internal standard (IS). The assay is rapid, sensitive, and simple to perform. It involves a liquid-liquid extraction procedure with simultaneous in-solution derivatization of the organic layer with pentafluorobenzoyl chloride (PFB-CI), followed by GC/MS analysis. These derivatives and the IS were extracted from 1 mL alkaline urine into hexane before derivatization with PFB-CI. The organic layer was then removed and evaporated to dryness before dissolution with hexane for GC/MS analysis. Calibration curves for each analyte showed linearity in the range of 25-5000 ng/mL (r2 > or = 0.997). Recoveries ranged from 88 to 99%, with the precision of recoveries typically < or = 5%. The LOD values ranged from 7 to 28 ng/mL, and the LOQ values ranged from 23 to 94 ng/mL. At least four ions were available for each analyte for confirmation of identity by MS.


Asunto(s)
Cromatografía de Gases y Espectrometría de Masas/métodos , Simpatomiméticos/orina , 3,4-Metilenodioxianfetamina/análogos & derivados , 3,4-Metilenodioxianfetamina/orina , Anfetamina/orina , Efedrina/orina , Cromatografía de Gases y Espectrometría de Masas/normas , Cromatografía de Gases y Espectrometría de Masas/estadística & datos numéricos , Humanos , Mefentermina/orina , Metanfetamina/orina , Estructura Molecular , N-Metil-3,4-metilenodioxianfetamina/orina , Seudoefedrina/orina , Estándares de Referencia , Simpatomiméticos/química , Simpatomiméticos/normas
17.
J AOAC Int ; 92(4): 1027-34, 2009.
Artículo en Inglés | MEDLINE | ID: mdl-19714968

RESUMEN

A validated analytical method is reported for the analysis of paeoniflorin and albiflorin in Bai Shao (Paeonia lactiflora) as a dried raw herb and commercially prepared dried aqueous extract. The samples were extracted by sonication in methanol and the extract analyzed by LC-photodiode array with identity confirmation by electrospray ionization-tandem MS. A C18 column was used with an acetonitrile-water gradient mobile phase. Paeoniflorin and albiflorin were quantified at 230 nm. Ions with m/z 121 and 327 were produced with the MS detector, using the paeoniflorin precursor ion with m/z 479. For albiflorin, the precursor ion with m/z 479 produced the m/z 121 and 77 ions. The amounts of paeoniflorin and albiflorin found in the raw herb were 33.2 and 1.8 mg/g, respectively; and in the dried aqueous extract, the amounts were 34.8 and 15.7 mg/g, respectively. The LODs for paeoniflorin and albiflorin were 0.37 and 1.39 mg/g, respectively, for the raw herb and 0.25 and 0.06 mg/g, respectively, for the dried aqueous extract.


Asunto(s)
Benzoatos/análisis , Hidrocarburos Aromáticos con Puentes/análisis , Glucósidos/análisis , Paeonia/química , Cromatografía Liquida , Cromatografía en Capa Delgada , Indicadores y Reactivos , Medicina Tradicional China , Monoterpenos , Extractos Vegetales/análisis , Preparaciones de Plantas/análisis , Estándares de Referencia , Solventes , Espectrometría de Masa por Ionización de Electrospray , Espectrofotometría Ultravioleta
18.
J AOAC Int ; 92(3): 789-96, 2009.
Artículo en Inglés | MEDLINE | ID: mdl-19610369

RESUMEN

A validated analytical method is reported for the analysis of narirutin and hesperidin in Zhi Ke (Citrus aurantium L.) in the form of the dried raw herb and of the commercially prepared dried aqueous extract. The samples were extracted by sonication in methanol and the extract was analyzed by liquid chromatography-photodiode array (PDA) detection with identity confirmation by negative electrospray ionization-tandem mass spectrometry (MS). A C18 column was used with a methanol-water gradient mobile phase. Narirutin and hesperidin were quantified at 284 nm using the PDA detector. Using the MS detector, the narirutin precursor ion with m/z 579 produced daughter ions with m/z 271 and 151. For hesperidin, the precursor ion with m/z 609 produced the m/z 301, 285, and 164 ions. The amounts of narirutin and hesperidin found in the certified raw herb were 14.2 and 147.9 mg/g, respectively, and in the dried aqueous extract the amounts were 9.2 and 8.6 mg/g, respectively. For the raw herb, the average recovery across the three spike levels (50, 100, and 150%) for narirutin and hesperidin were 110.7 and 94.5%, respectively. For the dried aqueous extract, the average recovery across the three spike levels for narirutin and hesperidin were 85.8 and 98.9%, respectively.


Asunto(s)
Cromatografía Liquida/métodos , Citrus/química , Disacáridos/análisis , Flavanonas/análisis , Hesperidina/análisis , Extractos Vegetales/análisis , Espectrometría de Masa por Ionización de Electrospray
19.
J AOAC Int ; 90(5): 1219-26, 2007.
Artículo en Inglés | MEDLINE | ID: mdl-17955965

RESUMEN

The determination of 6-, 8-, 10-gingerol, and 6-shogaol in dried ginger (Zingiber officinale) and in the dried aqueous extract of ginger is reported. This is the first study to report a validated method for the determination of these 4 analytes. Several extraction solvents and methods were examined, and the optimum combination was determined. The samples were extracted at room temperature by sonication with methanol, and the extract was analyzed by liquid chromatography with photodiode array detection. A C18 column was used with a water-acetonitrile gradient mobile phase. Quantification was at 200 nm. The levels of 6-, 8-, 10-gingerol, and 6-shogaol in the raw herb were 9.3, 1.6, 2.3, and 2.3 mglg, respectively. The levels of gingerols found in the dried aqueous extract were between 5 and 16 times lower than those in the raw herb, but the level of 6-shogaol was higher. Analyte identity was confirmed by negative-ion electrospray ionization tandem mass spectrometry, in which 2 daughter ions were obtained for each analyte. The average recovery was 97% with a relative standard deviation of <8%. The limits of detection for 6-, 8-, 10-gingerol, and 6-shogaol in the raw herb were 0.22, 0.04, 0.09, and 0.07 mglg, respectively, and in the dried aqueous extract, 0.11, 0.02, 0.02, and 0.14 mg/g, respectively.


Asunto(s)
Catecoles/análisis , Catecoles/química , Cromatografía Liquida/métodos , Alcoholes Grasos/análisis , Alcoholes Grasos/química , Extractos Vegetales/análisis , Extractos Vegetales/química , Agua/química , Zingiber officinale/metabolismo , Acetonitrilos/química , Iones , Espectrometría de Masas/métodos , Modelos Químicos , Preparaciones de Plantas/química , Solventes/química , Espectrometría de Masa por Ionización de Electrospray/métodos
20.
J AOAC Int ; 90(5): 1210-8, 2007.
Artículo en Inglés | MEDLINE | ID: mdl-17955964

RESUMEN

A validated analytical method is described for the determination of honokiol and magnolol in Hou Po (Magnolia officinalis) as the dried raw herb and the commercially prepared dried aqueous extract. The samples were extracted with methanol by the Soxhlet method, and the extract was analyzed by liquid chromatography with photodiode array (LC/PDA) detection with confirmation of analyte identity by negative-ion electrospray ionization tandem mass spectrometry (ESI-MS/MS). A C18 column was used with a menthanol--0.1% aqueous acetic acid gradient mobile phase. Honokiol and magnolol were quantified at 288 nm. With the MS detector, the honokiol precursor ion at m/z 265 was shown to produce ions at m/z 222 and 224. For magnolol, the precursor ion at m/z 265 produced the ions at m/z 247 and 245. Comparable results were obtained for the LC/PDA and LC/ESI-MS/MS methods of quantitation. Six commercially prepared dried aqueous extracts were analyzed. The levels of honokiol and magnolol found in the raw herb were 17.0 and 21.3 mg/g, respectively. The limits of detection for honokiol and magnolol in the raw herb were 0.45 and 0.58 mg/g, respectively, and in the dried aqueous extract, 0.04 and 0.30 mg/g, respectively.


Asunto(s)
Compuestos de Bifenilo/análisis , Cromatografía Liquida/métodos , Lignanos/análisis , Extractos Vegetales/análisis , Compuestos de Bifenilo/química , Calibración , Iones , Lignanos/química , Magnolia/metabolismo , Espectrometría de Masas , Metanol/química , Modelos Químicos , Extractos Vegetales/química , Preparaciones de Plantas , Estándares de Referencia , Solventes/química , Espectrometría de Masa por Ionización de Electrospray , Agua/química
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