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Nordihydroguaiaretic Acid from Creosote Bush (Larrea tridentata) Mitigates 12-O-Tetradecanoylphorbol-13-Acetate-Induced Inflammatory and Oxidative Stress Responses of Tumor Promotion Cascade in Mouse Skin
Shakilur Rahman,Rizwan Ahmed Ansari,Hasibur Rehman,Suhel Parvez,Sheikh Raisuddin
Evidence-Based Complementary and Alternative Medicine , 2011, DOI: 10.1093/ecam/nep076
Abstract: Nordihydroguaiaretic acid (NDGA) is a phenolic antioxidant found in the leaves and twigs of the evergreen desert shrub, Larrea tridentata (Sesse and Moc. ex DC) Coville (creosote bush). It has a long history of traditional medicinal use by the Native Americans and Mexicans. The modulatory effects of topically applied NDGA was studied on acute inflammatory and oxidative stress responses in mouse skin induced by stage I tumor promoting agent, 12-O-tetradecanoylphorbol-13-acetate (TPA). Double TPA treatment adversely altered many of the marker responses of stage I skin tumor promotion cascade. Pretreatment of NDGA in TPA-treated mice mitigated cutaneous lipid peroxidation and inhibited production of hydrogen peroxide. NDGA treatment also restored reduced glutathione level and activities of antioxidant enzymes. Elevated activities of myeloperoxidase, xanthine oxidase and skin edema formation in TPA-treated mice were also lowered by NDGA indicating a restrained inflammatory response. Furthermore, results of histological study demonstrated inhibitory effect of NDGA on cellular inflammatory responses. This study provides a direct evidence of antioxidative and anti-inflammatory properties of NDGA against TPA-induced cutaneous inflammation and oxidative stress corroborating its chemopreventive potential against skin cancer.
Photosynthesis and water use efficiency of the association between Larrea tridentata (DC) Cov. and Muhlenbergia porteri Scribn
Castellanos-Pérez,E; de Soyza,Ag; Donart,Gb;
Phyton (Buenos Aires) , 2008,
Abstract: the study was conducted in the chihuahuan desert rangeland research center, 32 km north of las cruces, nm, usa. physiological responses of the shrub larrea tridentata (dc) cov. and the perennial grass muhlenbergia porteri scribn were determined from the summer 1997 to the winter 1998-99 when they grew together. in the summer 1997 larrea tridentata competed for water with m. porteri, as shrubs growing alone showed higher integrated photosynthesis than shrubs in competi-tion with m. porteri following a heavy rainfall event. larrea tridentata had lower water use efficiency (wue) than m. porteri plants. in the summer 1998 m. porteri had greater pre-dawn xylem water potentials (ψl) than l. tridentata when soil water potentials were above -3 mpa. larrea tridentata showed a higher photosynthetic activity when m. porteri was defoliated than when it remained undefoliated. muhlenbergia porteri presented a higher wue. while green in the fall, plants of m. porteri had higher ψl and wue than those of l. tridentata. net assimilation was similar between shrub and grass plants. both species responded to soil moisture availability in this season. muhlenbergia porteri had higher net assimilation when growing alone than when growing under creosotebush. in the winter season, and while being small, creosotebush had higher photosynthetic activity when growing alone than when growing with m. porteri (p<0.005). small and large plants of l. tridentata growing alone showed higher photosynthetic activity than l. tridentata growing with m. porteri (p<0.01). in the spring, m. porteri and l. tridentata had the same net assimilation. at this time, however, water loss was lower in m. porteri than in l. tridentata. when soil water potential decreased below -7 mpa, l. tridentata still showed net assimilation.
Volatile organic compound emissions from Larrea tridentata (creosotebush)
K. Jardine, L. Abrell, S. A. Kurc, T. Huxman, J. Ortega,A. Guenther
Atmospheric Chemistry and Physics (ACP) & Discussions (ACPD) , 2010,
Abstract: We present results from the CREosote ATmosphere Interactions through Volatile Emissions (CREATIVE 2009) field study in southern Arizona aimed at quantifying emission rates of VOCs from creosotebush (Larrea tridentata) during the summer 2009 monsoon season. This species was chosen because of its vast distribution in North and South American deserts and because its resins have been reported to contain a rich set of volatile organic compounds (VOC). While a variety of ecosystems have been investigated for VOC emissions, deserts remain essentially unstudied, partially because of their low biomass densities and water limitations. However, during the North American monsoon, a pronounced increase in rainfall from an extremely dry June (<5 mm precipitation) to a rainy July (>80 mm) occurs over large areas of the Sonoran desert in the southwestern United States and northwestern Mexico. We observed a strong diurnal pattern of branch emissions and ambient concentrations of an extensive suite of VOCs with maxima in early afternoon. These include VOCs typically observed in forest sites (oxygenated VOCs and volatile isoprenoids) as well as a large number of other compounds, some of which have not been previously described from any plant including 1-chloro-2-methoxy-benzene and isobutyronitrile. Although generally considered to be derived from anthropogenic sources, we observed emissions of aromatic compounds including benzene, and a broad range of phenolics. Dimethyl sulfide emissions from creosotebush were higher than reported from any previously studied plant suggesting that terrestrial ecosystems should be reconsidered as an important source of this climatically important gas. We also present direct, primary emission measurements of isoprene and its apparent oxidation products methyl vinyl ketone, methacrolein, and 3-methyl furan (the later three compounds are typically assumed to form from secondary reactions within the atmosphere), as well as a group of compounds considered to be fatty acid oxidation products. These results suggest that one important function of some VOCs in creosotebush is as an antioxidant. We also find that emissions of nitriles from creosotebush could represent a significant but previously unaccounted nitrogen loss from this arid ecosystem. Our results demonstrate the richness of creosotebush volatile emissions and highlight the need for further research into their atmospheric and ecological impacts.
Exposition of Pecan Black Aphid (Melanocallis caryaefoliae) to Creseote Bush (Larrea tridentata) Extracts  [PDF]
Monica Marín-Domínguez, Ramona Pérez-Leal, Abelardo Nú?ez-Barrios, Moises Basurto-Sotelo, Juan Manuel Soto-Parra
Agricultural Sciences (AS) , 2014, DOI: 10.4236/as.2014.514147
Abstract: Creseote bush-based (Larrea tridentata Cov.) botanical insecticides have not been evaluated on pecan black aphid (Melanocallis caryaefoliae D.), the purpose of this research was to test the insecticide and/or repellent effect of the creseote-bush raw extracts on this insect. Ethyl acetate, methanol and water as solvents, the stem and leaf organs were tested at concentrations of 0.5%, 1%, and 2%, as well as their witnesses and the interactions of each. Extract application was made by immersion during 10 s and the incubation was made in a wet chamber, making observations at 24, 48 and 72 hours after the treatment was applied. Mortality was evaluated by touching the aphid and seeing it did not move, while for repellence the insects found outside of the leaf were taken into account. A higher mortality effect was observed at a 1% concentration for the three solvents on the leaf extracts, being the methanol one the most efficient, on the other hand the stem extracts had the same behavior, presenting the higher mortality in the ethyl acetate extracts at 0.5% and 2% both at 72 hours. On the other hand the higher repellent effect presented at 24 hours in stem extracts, with a variation in the leaf extracts.
Identidad de Physalis coztomatl Moc. & Sesse ex Dunal como el coztomatl de Francisco Hernández  [cached]
Mahinda Martinez
Acta botánica mexicana , 1994,
Abstract: Physalis coztomatl Moc. & Sessé ex Dunal es coespecífica con P. stapelioides (Regel) Bitter, sobre el que tiene prioridad, por lo que debe utilizarse para el semiarbusto común de los bosques de México. El epíteto específico proviene de las obras de Francisco Hernández, y la descripción está basada en un dibujo de la Iconografía Inédita de Sessé y Moci o.
Potencial antifúngico de cepas de Bacillusspp. y extracto de Larrea tridentatacontra Rhizoctonia solanien el cultivo de la papa (Solanum tuberosum L.)
Hernández-Castillo,FD; Lira-Saldivar,RH; Cruz-Chávez,L; Gallegos-Morales,G; Galindo-Cepeda,Me; Padrón-Corral,E; Hernández-Suárez,M;
Phyton (Buenos Aires) , 2008,
Abstract: potato crop requires more fungicides than any other crop in mexico to prevent and control several diseases. more than 21,3% of the total available fungicides are required for cropping potato. high quantities of synthetic pesticides are intended to control phytophthora infestans and rhizoctonia solani fungi. as a result, this produces severe health problems and ecosystem disturbances. there is then an urgent need for finding new options for sustainable management of potato crop diseases. several experiments were conducted under laboratory, greenhouse, and field conditions, to: (1) analyze the antifungal effect of bacteria strains of the genus bacillus, and their effect on potato plant growth; (2) determine the effect of a resinous extract from larrea tridentata leaves against the fungus r. solani, and (3) establish if there is a synergic effect when bacillus spp. are mixed with l. tridentata extract. results indicate an antifungal effect of bacterial strains and larrea extract. bacillus strains also stimulated plant growth and yield increase. a synergic effect was detected when bacillus spp. were mixed with larrea extract; a similar outcome occurred with the mixture of b3, b9 and b15 strains. results obtained with bacillus and larrea, as well as with their mixture are encouraging since they could be used as an organic option for biological control programs against the fungus r. solani. however, more in vivo research is necessary to validate these results.
Cuauhtémoc regained  [cached]
Christopher Fulton
Estudios de historia moderna y contemporánea de México , 2008,
Abstract: This essay continues the investigation of an earlier article, also published in this journal, by examining artistic representations of Cuauhtémoc in the post-revolutionary period, and especially after 1940, when the figure of the last Aztec king became widely and variously deployed as a political and cultural emblem. The essay will describe how in the post-revolutionary era internal contradictions, which were latent within the imagery, broke into the open and ignited controversy over the meaning and use of the Cuauhtémoc symbol. Este ensayo continúa la investigación realizada en un artículo anterior también publicado en esta revista, examinando las representaciones artísticas de Cuauhtémoc en el periodo posrevolucionario, especialmente después de 1940, cuando la imagen del último emperador azteca fue concebida como un símbolo nacional. Muestra la manera en la que en este periodo las contradicciones internas, que eran latentes dentro del imaginario, llevaron a una controversia abierta y encendida sobre el significado y el empleo del símbolo de Cuauhtémoc.
LE SESSE DEL LAGO DI BOLSENA
D. DI FILIPPO
Annals of Geophysics , 1951, DOI: 10.4401/ag-5904
Abstract: Si pungono a confronto i risultati teorici degli elementi delletre prime sesse del lago di Bolsena, calcolati con i metodi di Hidakae di Defant, con quelli delle registrazioni ottenute contemporaneamentea Marta e a Bolsena da L. Palazzo il 20 luglio 1903. Vieneconstatata la perfetta concordanza tra gli uni e gli altri a convalidadella bontà dei procedimenti teorici.
Le sesse (seickes) dell'Adriatico
s. polli
Annals of Geophysics , 1958, DOI: 10.4401/ag-5741
Abstract: Il mare Adriatico, come ogni bacino acqueo,è soggetto ad oscillazioni libere, aventiperiodi determinati, dipendenti dalla formadel bacino e dal modo di oscillazione. Ilfenomeno si genera quando una causa, generalmentemeteorica, produce un temporaneodislivello in una zona del mare. Ilristabilimento dell'equilibrio avviene medianteuna successione di oscillazioni chegradualmente si smorzano. Queste fluttuazionisono dette anche sesse (seiches, freeoscillations, Eigenschwingungen) perchè sottotale nome furono per la prima volta osservatee studiate nei grandi laghi svizzeri.Nell'Adriatico l'oscillazione principale avvienelongitudinalmente, l'acqua cioè oscillaattorno ad una linea nodale, trasversale all'assedel bacino. Sono possibili oscillazionicon la linea nodale all'estremità aperta delmare, con il nodo al centro, con più lineenodali ed anche oscillazioni trasversali.
Effects of natural phenolic compounds from a desert dominant shrub Larrea divaricata Cav. on toxicity and survival in mice Efectos de los compuestos fenólicos naturales de un arbusto dominante del desierto, Larrea divaricata Cav. sobre la toxicidad y sobrevida en ratones
J.M. RíOS,A.M. MANGIONE,J.C. GIANELLO
Revista chilena de historia natural , 2008,
Abstract: It is known that generalist herbivores may circumvent intoxication by ingesting small quantities from a mixture of plant secondary metabolites. However a single chemical, a highly toxic one or the most abundant in the mixture could cause toxicity. Survivorship and toxicity in Rockland male mice were measured to determine if the toxic effects of the phenolic resin of creosote bush (Larrea divaricata Cav.) is due to its major constituent, the nordihydroguaiaretic acid (NDGA) or to the total concentration of phenolic compounds in this resin. This objective was accomplished by exposing mice to voluntary feeding on resin-treated rat chow and by oral gavaging of mice with the following doses and compounds: Resin-100 mg (n = 7), NDGA-15 mg (n = 8), and NDGA-100 mg (n = 10) and Control (n = 6). Our hypothesis was that NDGA is responsible for the toxicity of Larrea divaricata's phenolic resin. Voluntary resin intake by mice had a pronounced toxic effect, producing body mass loss and significant reduction of food intake. Mice gavaged with Resin-100 mg, NDGA-100 mg, and NDGA-15 mg showed a significant reduction in survival probability compared to mice under Control conditions. Animáis exposed to NDGA-15 mg had a higher survivorship compared to the NDGA-100 mg animáis, and equivalent survivorship to the Resin-100 mg (containing 15 mg of NDGA) animáis. No significant differences in detoxification, measured as glucuronic acid conjugates in urine, were detected among gavage treatments. Therefore, given that just 15 mg of NDGA were enough to produce the same effect as the whole resin, we suggest that NDGA is the main constituent of Larrea divaricata's resin responsible for the toxic effect of the phenolic resin of this plant. Los herbívoros generalistas pueden evitar la intoxicación ingiriendo peque as cantidades de una mezcla de metabolitos secundarios de plantas. Sin embargo, un solo compuesto, uno altamente tóxico o el más abundante en la mezcla es el que podría causar la intoxicación. La sobrevida y la toxicidad en ratones Rockland machos fueron evaluadas para determinar si los efectos tóxicos de la resina fenólica de jarilla (Larrea divaricata Cav.) se debe a su compuesto mayoritario, el ácido nordihidroguaiarético (ANDG) o a la concentración total de compuestos fenólicos en esta resina. Este objetivo fue logrado mediante la exposición de ratones a la alimentación voluntaria de alimento para rata tratado con resina y mediante el gavage oral de ratones con las siguientes dosis y compuestos: Resina-100 mg (n = 7), ANDG-15 mg (n = 8), ANDG-100 mg (n = 10) y Control (n
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