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1.
Int J Mol Sci ; 21(9)2020 May 09.
Artículo en Inglés | MEDLINE | ID: mdl-32397562

RESUMEN

Bacopa monnieri L. Wettst. (BM) is a botanical component of Ayurvedic medicines and of dietary supplements used worldwide for cognitive health and function. We previously reported that administration of BM alcoholic extract (BME) prevents trimethyltin (TMT)-induced cognitive deficits and hippocampal cell damage and promotes TMT-induced hippocampal neurogenesis. In this study, we demonstrate that administration of BME improves spatial working memory in adolescent (5-week- old) healthy mice but not adult (8-week-old) mice. Moreover, improved spatial working memory was retained even at 4 weeks after terminating 1-week treatment of adolescent mice. One-week BME treatment of adolescent mice significantly enhanced hippocampal BrdU incorporation and expression of genes involved in neurogenesis determined by RNAseq analysis. Cell death, as detected by histochemistry, appeared not to be significant. A significant increase in neurogenesis was observed in the dentate gyrus region 4 weeks after terminating 1-week treatment of adolescent mice with BME. Bacopaside I, an active component of BME, promoted the proliferation of neural progenitor cells in vitro in a concentration-dependent manner via the facilitation of the Akt and ERK1/2 signaling. These results suggest that BME enhances spatial working memory in healthy adolescent mice by promoting hippocampal neurogenesis and that the effects of BME are due, in significant amounts, to bacopaside I.


Asunto(s)
Bacopa/química , Giro Dentado/efectos de los fármacos , Trastornos de la Memoria/tratamiento farmacológico , Memoria a Corto Plazo/efectos de los fármacos , Neurogénesis/efectos de los fármacos , Nootrópicos/uso terapéutico , Extractos Vegetales/uso terapéutico , Memoria Espacial/efectos de los fármacos , Animales , Células Cultivadas , Replicación del ADN/efectos de los fármacos , Giro Dentado/fisiopatología , Regulación de la Expresión Génica/efectos de los fármacos , Masculino , Aprendizaje por Laberinto/efectos de los fármacos , Medicina Ayurvédica , Trastornos de la Memoria/inducido químicamente , Trastornos de la Memoria/fisiopatología , Ratones , Células-Madre Neurales/efectos de los fármacos , Neurogénesis/genética , Nootrópicos/farmacología , Extractos Vegetales/farmacología , RNA-Seq , Saponinas/farmacología , Maduración Sexual , Transducción de Señal/efectos de los fármacos , Compuestos de Trimetilestaño/toxicidad , Triterpenos/farmacología
3.
Metabolomics ; 13(11)2017 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-32754008

RESUMEN

INTRODUCTION: Botanicals containing iridoid and phenylethanoid/phenylpropanoid glycosides are used worldwide for the treatment of inflammatory musculoskeletal conditions that are primary causes of human years lived with disability (YLDs), such as arthritis and lower back pain. OBJECTIVES: We report the analysis of candidate anti-inflammatory metabolites of several endemic Scrophularia species and Verbascum thapsus used medicinally by peoples of North America. METHODS: Leaves, stems, and roots were analyzed by ultra-performance liquid chromatography-mass spectrometry (UPLC-MS) and partial least squares-discriminant analysis (PLS-DA) was performed in MetaboAnalyst 3.0 after processing the datasets in Progenesis QI. RESULTS: Comparison of the datasets revealed significant and differential accumulation of iridoid and phenylethanoid/phenylpropanoid glycosides in the tissues of the endemic Scrophularia species and Verbascum thapsus. CONCLUSIONS: Our investigation identified several species of pharmacological interest as good sources for harpagoside and other important anti-inflammatory metabolites.

4.
Cell Biol Int ; 40(2): 131-42, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26377232

RESUMEN

Sutherlandia frutescens is a medicinal plant, traditionally used to treat various types of human diseases, including cancer. Previous studies of several botanicals link suppression of prostate cancer growth with inhibition of the Gli/hedgehog (Gli/Hh) signaling pathway. Here we hypothesized the anti-cancer effect of S. frutescens was linked to its inhibition of the Gli/Hh signaling in prostate cancer. We found a dose- and time-dependent growth inhibition in human prostate cancer cells, PC3 and LNCaP, and mouse prostate cancer cell, TRAMP-C2, treated with S. frutescens methanol extract (SLE). We also observed a dose-dependent inhibition of the Gli-reporter activity in Shh Light II and TRAMP-C2QGli cells treated with SLE. In addition, SLE can inhibit Gli/Hh signaling by blocking Gli1 and Ptched1 gene expression in the presence of a Gli/Hh signaling agonist (SAG). A diet supplemented with S. frutescens suppressed the formation of poorly differentiated carcinoma in prostates of TRAMP mice. Finally, we found Sutherlandioside D was the most potent compound in the crude extract that could suppress Gli-reporter in Shh Light II cells. Together, this suggests that the S. frutescens extract may exert anti-cancer effect by targeting Gli/Hh signaling, and Sutherlandioside D is one of the active compounds.


Asunto(s)
Proteínas Hedgehog/antagonistas & inhibidores , Factores de Transcripción de Tipo Kruppel/antagonistas & inhibidores , Extractos Vegetales/farmacología , Neoplasias de la Próstata/tratamiento farmacológico , Factores de Transcripción/antagonistas & inhibidores , Animales , Antineoplásicos/farmacología , Línea Celular Tumoral , Relación Dosis-Respuesta a Droga , Fabaceae/química , Expresión Génica , Humanos , Masculino , Ratones , Ratones Endogámicos A , Neoplasias de la Próstata/metabolismo , Neoplasias de la Próstata/patología , Distribución Aleatoria , Transducción de Señal , Proteína con Dedos de Zinc GLI1
5.
Plant Cell Rep ; 35(10): 2065-76, 2016 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-27350252

RESUMEN

KEY MESSAGE: A rapid and efficient Agrobacterium -mediated transformation system in sorghum has been developed employing standard binary vectors and bar gene as a selectable marker. Sorghum (Sorghum bicolor) is an important food and biofuel crop worldwide, for which improvements in genetic transformation are needed to study its biology and facilitate agronomic and commercial improvement. Here, we report optimization of regeneration and transformation of public sorghum genotype P898012 using standard binary vectors and bar gene as a selectable marker. The tissue culture regeneration time frame has been reduced to 7-12 weeks with a yield of over 18 plants per callus, and the optimized transformation system employing Agrobacterium tumefaciens strain AGL1 and the bar with a MAS promoter achieved an average frequency over 14 %. Of randomly analyzed independent transgenic events, 40-50 % carry single copy of integrated T-DNA. Some independent transgenic events were derived from the same embryogenic callus lines, but a 3:1 Mendelian segregation ratio was found in all transgenic events with single copy as estimated by Southern blots. The system described here should facilitate studies of sorghum biology and agronomic improvement.


Asunto(s)
Agrobacterium tumefaciens/genética , Genes Bacterianos , Vectores Genéticos/metabolismo , Transformación Genética , Southern Blotting , Segregación Cromosómica/genética , Marcadores Genéticos , Genotipo , Glucuronidasa/metabolismo , Herbicidas/toxicidad , Plantas Modificadas Genéticamente , Regiones Promotoras Genéticas/genética , Regeneración , Sorghum/genética , Coloración y Etiquetado , Técnicas de Cultivo de Tejidos
6.
Plant Mol Biol ; 87(4-5): 329-39, 2015 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-25600937

RESUMEN

AtMSI4/FVE/ACG1, one of five Arabidopsis thaliana genes encoding MSI1-like proteins, helps determine plant growth and development (including control of flowering), as well as responses to certain biotic and abiotic stresses. We reasoned that the product of this gene, AtMSI4, acts through protein partners, which we have co-immunopurified with AtMSI4 from A. thaliana suspension culture cells and identified by liquid chromatography-mass spectrometry (LC-MS). Many of the proteins associated with AtMSI4 have distinct RNA recognition motif (RRM) domains, which we determined to be responsible for association with AtMSI4; and most of the associated RRM domain proteins also contain PWWP domains that are specific to plants. We propose these novel ATMSI4-associated proteins help form nucleoprotein complexes that determine pleiotropic functional properties of AtMSI4/FVE/ACG1 involving plant development and responses to stress.


Asunto(s)
Proteínas de Arabidopsis/química , Proteínas de Arabidopsis/metabolismo , Arabidopsis/metabolismo , Proteínas Portadoras/metabolismo , Unión Proteica , Estructura Terciaria de Proteína , Factores de Transcripción
7.
Public Underst Sci ; 24(5): 563-81, 2015 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-25605748

RESUMEN

We empirically examine the reporting on biotechnology in Kenyan and international newspapers between 2010 and early 2014. We identify news articles that reported on biotechnology and analyze their use of words to determine whether there is a balance in the reporting of perceived risks and benefits. We also consider how the sources used in news articles and how the publication of the Séralini study of rats fed genetically modified maize affect the balance of reporting of perceived risks and benefits. We find that in Kenyan news reporting, more articles mention perceived benefits than risks, but when risks are mentioned, new articles contain more references to risks than to benefits. We also find that sources affect the reporting of perceived risks and benefits and that the Séralini study increased the likelihood that perceived risks are reported in Kenyan news reporting, but not in international newspapers.


Asunto(s)
Productos Agrícolas/genética , Alimentos Modificados Genéticamente/efectos adversos , Difusión de la Información , Periodismo , Manihot/genética , Plantas Modificadas Genéticamente/efectos adversos , Opinión Pública , Kenia , Periódicos como Asunto
8.
BMC Complement Altern Med ; 14: 271, 2014 Jul 29.
Artículo en Inglés | MEDLINE | ID: mdl-25070435

RESUMEN

BACKGROUND: Sutherlandia frutescens (L.) R.Br. (SF) is a South African plant that is widely used to treat stress, infections, cancer, and chronic diseases, many of which involve oxidative stress. The aim of the study was to quantitatively assess the antioxidant potential of SF extracts in cell-free system as well as in cell lines. METHODS: Dried SF vegetative parts were extracted using six different solvents, and the extracts were assessed for total phenolic and flavonoid contents, total reducing power, iron chelating capacity, and free radical scavenging power, including, scavenging of hydroxyl radicals, superoxide anions, nitric oxide, and hydrogen peroxide. We further investigated the freeze-dried hot water extract of SF (SFE) to assess its effect against oxidative stress induced by tert-butyl hydroperoxide (t-BHP), an organic peroxide. Three different cell lines: Chinese hamster ovary (CHO), human hepatoma (HepaRG), and human pulmonary alveolar carcinoma (A549) cells, were employed to determine cell viability, intracellular reactive oxygen species (ROS) levels, and reduced to oxidized glutathione levels (GSH/GSSG). RESULTS: The results indicated that: (1) SF extracts have significant antioxidant potential that is dependent upon the nature of the extraction solvent and (2) SFE protects against tBHP-induced oxidative stress in cells by scavenging ROS and preserving intracellular GSH/GSSG. CONCLUSION: Oxidative stress is implicated in a number of disorders, and due to the public's concerns about synthetic antioxidants, various natural antioxidants are being explored for their therapeutic potential. Our findings support claims for S. frutescens being a promising adjunctive therapeutic for oxidative stress-related health problems.


Asunto(s)
Antioxidantes/farmacología , Células/efectos de los fármacos , Fabaceae/química , Estrés Oxidativo/efectos de los fármacos , Extractos Vegetales/farmacología , Sustancias Protectoras/farmacología , Animales , Antioxidantes/química , Células CHO , Línea Celular , Supervivencia Celular , Células/metabolismo , Cricetulus , Glutatión/metabolismo , Humanos , Oxidación-Reducción , Extractos Vegetales/química , Sustancias Protectoras/química , Especies Reactivas de Oxígeno/metabolismo
9.
Nat Prod Rep ; 30(4): 584-92, 2013 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-23450245

RESUMEN

Natural products and related structures are essential sources of new pharmaceuticals, because of the immense variety of functionally relevant secondary metabolites of microbial and plant species. Furthermore, the development of powerful analytical tools based upon genomics, proteomics, metabolomics, bioinformatics and other 21st century technologies are greatly expediting identification and characterization of these natural products. Here we discuss the synergistic and reciprocal benefits of linking these 'omics technologies with robust ethnobotanical and ethnomedical studies of traditional medicines, to provide critically needed improved medicines and treatments that are inexpensive, accessible, safe and reliable. However, careless application of modern technologies can challenge traditional knowledge and biodiversity that are the foundation of traditional medicines. To address such challenges while fulfilling the need for improved (and new) medicines, we encourage the development of Regional Centres of 'omics Technologies functionally linked with Regional Centres of Genetic Resources, especially in regions of the world where use of traditional medicines is prevalent and essential for health.


Asunto(s)
Productos Biológicos , Plantas Medicinales/química , Antimaláricos/química , Antimaláricos/farmacología , Antituberculosos/química , Antituberculosos/farmacología , Productos Biológicos/química , Productos Biológicos/aislamiento & purificación , Productos Biológicos/farmacología , Descubrimiento de Drogas , Historia del Siglo XXI , Medicina Tradicional , Estructura Molecular , Preparaciones de Plantas/farmacología
10.
J Neuroinflammation ; 10: 15, 2013 Jan 29.
Artículo en Inglés | MEDLINE | ID: mdl-23356518

RESUMEN

BACKGROUND: The bark of magnolia has been used in Oriental medicine to treat a variety of remedies, including some neurological disorders. Magnolol (Mag) and honokiol (Hon) are isomers of polyphenolic compounds from the bark of Magnolia officinalis, and have been identified as major active components exhibiting anti-oxidative, anti-inflammatory, and neuroprotective effects. In this study, we investigate the ability of these isomers to suppress oxidative stress in neurons stimulated by the ionotropic glutamate receptor agonist N-methyl-D-aspartate (NMDA) and oxidative and inflammatory responses in microglial cells activated by interferon-γ (IFNγ) and lipopolysaccharide (LPS). We also attempt to elucidate the mechanism and signaling pathways involved in cytokine-induced production of reactive oxygen species (ROS) in microglial cells. METHODS: Dihydroethidium (DHE) was used to assay superoxide production in neurons, while CM-H2DCF-DA was used to test for ROS production in murine (BV-2) and rat (HAPI) immortalized microglial cells. NADPH oxidase inhibitors (for example, diphenyleneiodonium (DPI), AEBSF, and apocynin) and immunocytochemistry targeting p47phox and gp91phox were used to assess the involvement of NADPH oxidase. Western blotting was used to assess iNOS and ERK1/2 expression, and the Griess reaction protocol was employed to determine nitric oxide (NO) concentration. RESULTS: Exposure of Hon and Mag (1-10 µM) to neurons for 24 h did not alter neuronal viability, but both compounds (10 µM) inhibited NMDA-stimulated superoxide production, a pathway known to involve NADPH oxidase. In microglial cells, Hon and Mag inhibited IFNγ±LPS-induced iNOS expression, NO, and ROS production. Studies with inhibitors and immunocytochemical assay further demonstrated the important role of IFNγ activating the NADPH oxidase through the p-ERK-dependent pathway. Hon and, to a lesser extent, Mag inhibited IFNγ-induced p-ERK1/2 and its downstream pathway for ROS and NO production. CONCLUSION: This study highlights the important role of NADPH oxidase in mediating oxidative stress in neurons and microglial cells and has unveiled the role of IFNγ in stimulating the MAPK/ERK1/2 signaling pathway for activation of NADPH oxidase in microglial cells. Hon and Mag offer anti-oxidative or anti-inflammatory effects, at least in part, through suppressing IFNγ-induced p-ERK1/2 and its downstream pathway.


Asunto(s)
Compuestos de Bifenilo/farmacología , Mediadores de Inflamación/fisiología , Lignanos/farmacología , Magnolia , Microglía/metabolismo , Microglía/patología , Neuronas/metabolismo , Estrés Oxidativo/fisiología , Animales , Antiinflamatorios no Esteroideos/química , Antiinflamatorios no Esteroideos/farmacología , Antiinflamatorios no Esteroideos/uso terapéutico , Antioxidantes/química , Antioxidantes/farmacología , Antioxidantes/uso terapéutico , Compuestos de Bifenilo/química , Compuestos de Bifenilo/uso terapéutico , Línea Celular Transformada , Células Cultivadas , Inflamación/metabolismo , Inflamación/patología , Inflamación/prevención & control , Lignanos/química , Lignanos/uso terapéutico , Ratones , Microglía/efectos de los fármacos , Neuronas/efectos de los fármacos , Neuronas/patología , Estrés Oxidativo/efectos de los fármacos , Polifenoles/química , Polifenoles/farmacología , Polifenoles/uso terapéutico , Ratas , Ratas Sprague-Dawley , Especies Reactivas de Oxígeno/antagonistas & inhibidores , Especies Reactivas de Oxígeno/metabolismo
11.
J Virol ; 86(6): 3264-75, 2012 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-22205750

RESUMEN

BK polyomavirus (BKV) establishes persistent, low-level, and asymptomatic infections in most humans and causes polyomavirus-associated nephropathy (PVAN) and other pathologies in some individuals. The activation of BKV replication following kidney transplantation, leading to viruria, viremia, and, ultimately, PVAN, is associated with immune suppression as well as inflammation and stress from ischemia-reperfusion injury of the allograft, but the stimuli and molecular mechanisms leading to these pathologies are not well defined. The replication of BKV DNA in cell cultures is regulated by the viral noncoding control region (NCCR) comprising the core origin and flanking sequences, to which BKV T antigen (Tag), cellular proteins, and small regulatory RNAs bind. Six nuclear factor I (NFI) binding sites occur in sequences flanking the late side of the core origin (the enhancer) of the archetype virus, and their mutation, either individually or in toto, reduces BKV DNA replication when placed in competition with templates containing intact BKV NCCRs. NFI family members interacted with the helicase domain of BKV Tag in pulldown assays, suggesting that NFI helps recruit Tag to the viral core origin and may modulate its function. However, Tag may not be the sole target of the replication-modulatory activities of NFI: the NFIC/CTF1 isotype stimulates BKV template replication in vitro at low concentrations of DNA polymerase-α primase (Pol-primase), and the p58 subunit of Pol-primase associates with NFIC/CTF1, suggesting that NFI also recruits Pol-primase to the NCCR. These results suggest that NFI proteins (and the signaling pathways that target them) activate BKV replication and contribute to the consequent pathologies caused by acute infection.


Asunto(s)
Virus BK/genética , Replicación del ADN , Familia de Multigenes , Factores de Transcripción NFI/metabolismo , Infecciones por Polyomavirus/metabolismo , Infecciones Tumorales por Virus/metabolismo , Antígenos Virales de Tumores/genética , Antígenos Virales de Tumores/metabolismo , Virus BK/fisiología , Línea Celular , Humanos , Factores de Transcripción NFI/genética , Infecciones por Polyomavirus/genética , Infecciones por Polyomavirus/virología , Unión Proteica , Infecciones Tumorales por Virus/genética , Infecciones Tumorales por Virus/virología , Replicación Viral
12.
J Virol ; 85(14): 6930-40, 2011 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-21543481

RESUMEN

Small noncoding RNAs regulate a variety of cellular processes, including genomic imprinting, chromatin remodeling, replication, transcription, and translation. Here, we report small replication-regulating RNAs (srRNAs) that specifically inhibit DNA replication of the human BK polyomavirus (BKV) in vitro and in vivo. srRNAs from FM3A murine mammary tumor cells were enriched by DNA replication assay-guided fractionation and hybridization to the BKV noncoding control region (NCCR) and synthesized as cDNAs. Selective mutagenesis of the cDNA sequences and their putative targets suggests that the inhibition of BKV DNA replication is mediated by srRNAs binding to the viral NCCR, hindering early steps in the initiation of DNA replication. Ectopic expression of srRNAs in human cells inhibited BKV DNA replication in vivo. Additional srRNAs were designed and synthesized that specifically inhibit simian virus 40 (SV40) DNA replication in vitro. These observations point to novel mechanisms for regulating DNA replication and suggest the design of synthetic agents for inhibiting replication of polyomaviruses and possibly other viruses.


Asunto(s)
Virus BK/fisiología , ARN no Traducido , Replicación Viral , Animales , Secuencia de Bases , Línea Celular , Clonación Molecular , Cartilla de ADN , Replicación del ADN , ADN Viral/biosíntesis , ADN Viral/genética , Humanos , Ratones
13.
Nanotechnology ; 23(17): 175601, 2012 May 04.
Artículo en Inglés | MEDLINE | ID: mdl-22481044

RESUMEN

We report ultrabright, photostable, sub-25 nm nanoparticle agglomerates (suprananoparticles) assembled from a few hundred 3.3 ± 0.9 nm units, each hosting on average a single rhodamine 6G (Rh6G) dye molecule encased in a thin organosilicate cage. These individual Rh6G-doped nanoparticle (DOSNP) units consist of a hydrophobic core containing the dye and an ultrathin, conformal silicate shell modified by CO(2) plasma to confer a beneficial 'cage effect' as well as surface hydrophilicity. The isolation of the dye within individual DOSNP units in the final 22 ± 5 nm agglomerate avoids dimerization and related spontaneous molecular interactions that otherwise lead to self-quenching in closely co-localized fluorophores. The resulting suprananoparticles are over 200 times brighter than the free Rh6G molecules in the same volume. There is no observable dye leaching, and the labels are 20-fold more resistant to photobleaching than free Rh6G in solution. We demonstrate the attractive features of DOSNPs as labels in bioimaging applications.


Asunto(s)
Colorantes Fluorescentes/química , Nanopartículas/química , Compuestos de Organosilicio/química , Rodaminas/química , Interacciones Hidrofóbicas e Hidrofílicas , Tamaño de la Partícula , Fotoblanqueo , Espectrometría de Fluorescencia
14.
Sci Scope (Wash D C) ; 44(3): 37-43, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34149164

RESUMEN

Meeting the demands of the Next Generation Science Standards requires that students engage in complex science texts. However, for many students, including students with disabilities, this can be a challenging activity. Many students lack the necessary skills and background knowledge to successfully engage with complex science texts. In this article we discuss how to use instructional scaffolds to address gaps and challenges in reading as a way to engage all learners in complex science text.

15.
Metabolites ; 11(7)2021 Jul 19.
Artículo en Inglés | MEDLINE | ID: mdl-34357358

RESUMEN

Scrophularia lanceolata Pursh and Scrophularia marilandica L. are two common species within the Scrophulariaceae family that are endemic to North America. Historically, these species were used by indigenous peoples and colonialists to treat sunburn, sunstroke, frostbite, edema, as well as for blood purification, and in women's health. Several iridoid and phenylethanoid/phenylpropanoid glycosides detected in these species, such as harpagoside and verbascoside, possess anti-inflammatory and anti-nociceptive properties. Due to the presence of anti-inflammatory metabolites and the historical uses of these species, we performed a two-year field study to determine the optimal production of these important compounds. We subjected the plants to shade treatment and analyzed differences in the metabolite composition between the two species and each of their leaves, stems, and roots at various times throughout the growing seasons. We determined that S. lanceolata plants grown in full sun produced 0.63% harpagoside per dried weight in their leaves compared to shade-grown plants (0.43%). Furthermore, S. lanceolata accumulated more harpagoside than S. marilandica (0.24%). We also found that verbascoside accumulated in the leaves of S. lanceolata and S. marilandica as the growing season progressed, while the production of this metabolite remained mostly seasonally unchanged in the roots of both species.

16.
J Virol ; 83(11): 5708-17, 2009 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-19297467

RESUMEN

BK virus (BKV) causes persistent and asymptomatic infections in most humans and is the etiologic agent of polyomavirus-associated nephropathy (PVAN) and other pathologies. Unfortunately, there are no animal models with which to study activation of BKV replication in the human kidney and the accompanying PVAN. Here we report studies of the restriction of BKV replication in murine cells and extracts and the cause(s) of this restriction. Upon infection of murine cells, BKV expressed large T antigen (TAg), but viral DNA replication and progeny were not detected. Transfection of murine cells with BKV TAg expression vectors also caused TAg expression without accompanying DNA replication. Analysis of the replication of DNAs containing chimeric BKV and murine polyomavirus origins revealed the importance of BKV core origin sequences and TAg for DNA replication. A sensitive assay was developed with purified BKV TAg that supported TAg-dependent BKV DNA replication with human but not with murine cell extracts. Addition of human replication proteins, DNA polymerase alpha-primase, replication protein A, or topoisomerase I to the murine extracts with BKV TAg did not rescue viral DNA replication. Notably, addition of murine extracts to human extracts inhibited BKV TAg-dependent DNA replication at a step prior to or during unwinding of the viral origin. These findings and differences in replication specificity between BKV TAg and the TAgs of simian virus 40 (SV40) and JC virus (JCV) and their respective origins implicate features of the BKV TAg and origin distinct from SV40 and JCV in restriction of BKV replication in murine cells.


Asunto(s)
Virus BK/genética , Virus BK/metabolismo , Extractos Celulares/genética , Replicación del ADN/genética , ADN Viral/genética , Animales , Antígenos Virales de Tumores/genética , Antígenos Virales de Tumores/inmunología , Antígenos Virales de Tumores/metabolismo , Secuencia de Bases , Células Cultivadas , ADN Intergénico/genética , Humanos , Ratones
17.
Planta Med ; 76(2): 178-81, 2010 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-19670162

RESUMEN

Phytochemical investigation of the leaves of Sutherlandia frutescens led to the isolation of four new 3-hydroxy-3-methylglutaroyl-containing flavonol glycosides, sutherlandins A-D ( 1- 4). Their structures were elucidated by chemical and spectroscopic methods as quercetin 3- O- beta- D-xylopyranosyl(1 --> 2)-[6- O-(3-hydroxy-3-methylglutaroyl)]- beta- D-glucopyranoside ( 1), quercetin 3- O- beta- D-apiofuranosyl(1 --> 2)-[6- O-(3-hydroxy-3-methylglutaroyl)]- beta- D-glucopyranoside ( 2), kaempferol 3- O- beta- D-xylopyranosyl(1 --> 2)-[6- O-(3-hydroxy-3-methylglutaroyl)]- beta- D-glucopyranoside ( 3), and kaempferol 3- O- beta- D-apiofuranosyl(1 --> 2)-[6- O-(3-hydroxy-3-methylglutaroyl)]- beta- D-glucopyranoside ( 4).


Asunto(s)
Fabaceae/química , Flavonoles/aislamiento & purificación , Extractos Vegetales/química , Flavonoles/química , Glicósidos/aislamiento & purificación , Estructura Molecular , Extractos Vegetales/aislamiento & purificación , Hojas de la Planta , Plantas Medicinales
18.
BMC Complement Med Ther ; 20(1): 9, 2020 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-32020872

RESUMEN

BACKGROUND: A variety of medicinal products prepared from secondary tubers of Harpagophytum procumbens subsp. procumbens (Burch.) DC.ex Meisn. (Devil's Claw) and H. zeyheri are marketed in Africa, Europe, the United States, South America and elsewhere, where they are used for inflammatory and musculoskeletal conditions such as arthritis, lower back pain, rheumatism and neuralgia, etc. While clinical studies conducted over the last twenty years support the general safety of such products, infrequent gastrointestinal disturbances (diarrhea, nausea, vomiting, abdominal pain), headache, vertigo and hypersensitivity (allergic) reactions (rash, hives and face swelling) have been documented. Sex-related differences occur in the health conditions for which Devil's Claw products are used, so it is likely that usage is similarly sex-related and so might be side effects and potential toxicities. However toxicologic studies of Devil's Claw products have been conducted primarily with male animals. To address this deficit, we report toxicological studies in female and male rats of several H. procumbens (HP) aqueous-alcohol extracts chemically analyzed by UPLC-MS. METHODS: Female and male Sprague Dawley rats were studied for one and three months in groups differing by consumption of diets without and with HP extracts at a 7-10-fold human equivalent dose (HED). Sera were analyzed for blood chemistry, and heart, liver, lung, kidney, stomach, and small and large intestine tissues were examined for histopathology. Treatment group differences for blood chemistry were analyzed by ANOVA with Dunnett's test and significant group differences for endpoints with marginal distributional properties were verified using the Kruskal-Wallis test. Group differences for histopathology were tested using Chi Square analysis. RESULTS: Significant group by sex-related differences in blood chemistry were detected in both studies. Additionally, several sex-related differences occurred between the studies. However, significant histopathology effects associated with the consumption of the extracts were not detected. CONCLUSION: Toxicologic analysis of Devil's Claw extracts cause significant sex-related effects in blood chemistry. However, in our judgement, none of the observed effects suggest serious toxicity at these doses and durations. Subsequent toxicologic and clinical studies of H. procumbens and other medicines with similar properties should explore in greater detail the basis and consequences of potential sex-related effects.


Asunto(s)
Harpagophytum/toxicidad , Extractos Vegetales/toxicidad , África , Animales , Cromatografía Liquida , Femenino , Masculino , Ratas , Ratas Sprague-Dawley , Espectrometría de Masas en Tándem
19.
Int J Sci Math Educ ; 18(7): 1419-1439, 2020 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-34456658

RESUMEN

The affective domain and its impact on science achievement has been studied with increasing attention over the past decade. However, there has been little empirical work on how individual interest, and facilitation of situational interest in the classroom, facilitates learning of concepts within fine-grained units of instruction. Drawing upon previous theoretical and empirical work, we test the hypothesis that individual interest facilitates situational interest, and that this in turn facilitates content learning, with respect to a 10-day health education intervention focused on teaching middle school students about light, color and vision. We found that individual interest in science facilitates situational interest in the classroom activities and the teacher's instruction, and that situational interest has a positive and significant effect on learning concepts related to light and vision. Our data suggest that facilitating situational interest is a requirement if individual interest and prior knowledge are to be effective scaffolds for conceptual learning. However, targeting of other affective traits like motivation and engagement or cognitive processes like goal setting may be necessary to fully harness students' interest toward effective scaffolding of learning.

20.
Neuromolecular Med ; 22(2): 278-292, 2020 06.
Artículo en Inglés | MEDLINE | ID: mdl-31900786

RESUMEN

Spinal cord injury (SCI) is a deliberating disorder with impairments in locomotor deficits and incapacitating sensory abnormalities. Harpagophytum procumbens (Hp) is a botanical widely used for treating inflammation and pain related to various inflammatory and musculoskeletal conditions. Using a modified rodent contusion model of SCI, we explored the effects of this botanical on locomotor function and responses to mechanical stimuli, and examined possible neurochemical changes associated with SCI-induced allodynia. Following spinal cord contusion at T10 level, Hp (300 mg/kg, p.o.) or vehicle (water) was administered daily starting 24 h post-surgery, and behavioral measurements made every-other day until sacrifice (Day 21). Hp treatment markedly ameliorated the contusion-induced decrease in locomotor function and increased sensitivity to mechanical stimuli. Determination of Iba1 expression in spinal cord tissues indicated microglial infiltration starting 3 days post-injury. SCI results in increased levels of 4-hydroxynonenal, an oxidative stress product and proalgesic, which was diminished at 7 days by treatment with Hp. SCI also enhanced antioxidant heme oxygenase-1 (HO-1) expression. Concurrent studies of cultured murine BV-2 microglial cells revealed that Hp suppressed oxidative/nitrosative stress and inflammatory responses, including production of nitric oxide and reactive oxygen species, phosphorylation of cytosolic phospholipases A2, and upregulation of the antioxidative stress pathway involving the nuclear factor erythroid 2-related factor 2 and HO-1. These results support the use of Hp for management of allodynia by providing resilience against the neuroinflammation and pain associated with SCI and other neuropathological conditions.


Asunto(s)
Harpagophytum/química , Hiperalgesia/tratamiento farmacológico , Estrés Oxidativo/efectos de los fármacos , Fitoterapia , Extractos Vegetales/uso terapéutico , Traumatismos de la Médula Espinal/complicaciones , Aldehídos/metabolismo , Animales , Evaluación Preclínica de Medicamentos , Regulación de la Expresión Génica/efectos de los fármacos , Hemo Oxigenasa (Desciclizante)/biosíntesis , Hemo Oxigenasa (Desciclizante)/genética , Hiperalgesia/etiología , Inflamación , Masculino , Ratones , Actividad Motora/efectos de los fármacos , Factor 2 Relacionado con NF-E2/biosíntesis , Factor 2 Relacionado con NF-E2/genética , Ácido Nítrico/metabolismo , Extractos Vegetales/química , Extractos Vegetales/farmacología , Ratas , Ratas Sprague-Dawley , Especies de Nitrógeno Reactivo/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Método Simple Ciego , Tacto
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