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121.
Marmi J Casanovas-Vilar I Robles JM Moyà-Solà S Alba DM 《Journal of human evolution》2012,62(3):412-423
The early Vallesian site of Can Llobateres 1 (Vallès-Penedès Basin, Catalonia, Spain) is one of the richest localities of the European Late Miocene, having yielded the most complete remains of the fossil great ape Hispanopithecus laietanus (Primates: Hominidae). Fossil plant remains had been previously reported from this site but mostly remained unpublished. Here we describe an assemblage of plant megaremains recovered in 2010, which provides valuable paleoenvironmental data. This assemblage consists of a mixture of parautochthonous and allochthonous detached organs (leaves, stems, reproductive structures) deposited in marshy areas. The source vegetation mainly consisted of abundant reeds, palms, evergreen laurels and figs that probably grew in or near the marsh boundaries or nearby riparian forests. This environmental picture is consistent with the mammalian fauna, which shows the prevalence of humid forested environments, although somewhat more open woodlands might have been present away from the wet areas. The occurrence of mega-mesothermal taxa, together with the absence of deciduous elements, is consistent with a subtropical to warm-temperate climate. Within this mosaic environment, H. laietanus would have preferred the more humid and forested habitats, which probably were still quite common in the Vallès-Penedès during the early Vallesian. Such habitats would have provided a continuous ripe fruit supply throughout the year to these frugivorous great apes. Paleobotanical data from older sites of the same area and nearby basins show that the zonal vegetation was a warm-temperate mixed forest defined by evergreen laurels, together with leguminous trees and shrubs as well as a significant proportion of deciduous elements. Tropical and subtropical taxa would have been restricted to humid areas in the lowlands. From the late Vallesian onwards, many of these taxa disappeared from the Vallès-Penedès, whereas deciduous trees became dominant in the forested areas and wetlands, thus likely having driven Hispanopithecus to extinction in the study area. 相似文献
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BackgroundFour biopesticide prototypes formulated as dispersible granules and dry powders based on 2 Colombian isolates of Trichoderma koningiopsis (Th003) and T. asperellum (Th034) were developed. These microorganisms have antagonist activity against Fusarium oxysporum f. sp. lycopersici and Rhizoctonia solani with a reduction in incidence of between 70 and 100% in tomato crops and potato crops, respectively.AimTo determine the effect of the formulation on the shelf-life of 4 biopesticides based on T. koningiopsis Th003 and Trichoderma asperellum Th034 at 3 different temperatures.MethodsThe formulation effect was determined by evaluating the germination of unformulated and formulated conidia (dispersible granules and dry powder) stored at 8, 18 and 28 °C for 18 months. Germination kinetics were used to estimate the shelf-life by using different mathematical models (zero order, first order, second order, Higuchi model, Korsmeyer-Peppas model and polynomial model).ResultsThe products showed high stability of the conidia germination when they were stored at 8 and 18° C, with shelf-lives of 14.4 and 13.9 months for dry powder based on Th003, and 12.0 and 10.8 months for dry powder based on Th034, respectively. Prototypes formulated as dispersible granules stored at the same temperatures (8 and 18 °C) showed lower shelf-lives, with values of 11.6 and 10.9 months for the Th003 product, and 10.7 and 7.2 months for the dispersible granules based on Th034. Significant reductions in germination were observed on unformulated conidia at all storage temperatures evaluated.ConclusionsThe formulation type affected the conidia stability of the 2 Trichoderma spp. Colombian isolates. Dry powder was the prototype with the highest stability and shelf-life at all temperatures evaluated. 相似文献
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Rodent experiments have emphasized a role of central fatty acid (FA) species, such as oleic acid, in regulating peripheral glucose and energy metabolism. Thus, we hypothesized that central FAs are related to peripheral glucose regulation and energy expenditure in humans. To test this we measured FA species profiles in cerebrospinal fluid (CSF) and plasma of 32 individuals who stayed in our clinical inpatient unit for 6 days. Body composition was measured by dual energy X-ray absorptiometry and glucose regulation by an oral glucose test (OGTT) followed by measurements of 24 hour (24EE) and sleep energy expenditure (SLEEP) as well as respiratory quotient (RQ) in a respiratory chamber. CSF was obtained via lumbar punctures; FA concentrations were measured by liquid chromatography/mass spectrometry. As expected, FA concentrations were higher in plasma compared to CSF. Individuals with high concentrations of CSF very-long-chain saturated FAs had lower rates of SLEEP. In the plasma moderate associations of these FAs with higher 24EE were observed. Moreover, CSF monounsaturated long-chain FA (palmitoleic and oleic acid) concentrations were associated with lower RQs and lower glucose area under the curve during the OGTT. Thus, FAs in the CSF strongly correlated with peripheral metabolic traits. These physiological parameters were most specific to long-chain monounsaturated (C16∶1, C18∶1) and very-long-chain saturated (C24∶0, C26∶0) FAs. CONCLUSIONS: Together with previous animal experiments these initial cross-sectional human data indicate that central FA species are linked to peripheral glucose and energy homeostasis. 相似文献
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Jung KM Clapper JR Fu J D'Agostino G Guijarro A Thongkham D Avanesian A Astarita G DiPatrizio NV Frontini A Cinti S Diano S Piomelli D 《Cell metabolism》2012,15(3):299-310
The endocannabinoid system plays a critical role in the control of energy homeostasis, but the identity and localization of the endocannabinoid signal involved remain unknown. In the present study, we developed transgenic mice that overexpress in forebrain neurons the presynaptic hydrolase, monoacylglycerol lipase (MGL), which deactivates the endocannabinoid 2-arachidonoyl-sn-glycerol (2-AG). MGL-overexpressing mice show a 50% decrease in forebrain 2-AG levels but no overt compensation in other endocannabinoid components. This biochemical abnormality is accompanied by a series of metabolic changes that include leanness, elevated energy cost of activity, and hypersensitivity to β(3)-adrenergic-stimulated thermogenesis, which is corrected by reinstating 2-AG activity at CB(1)-cannabinoid receptors. Additionally, the mutant mice are resistant to diet-induced obesity and express high levels of thermogenic proteins, such as uncoupling protein 1, in their brown adipose tissue. The results suggest that 2-AG signaling through CB(1) regulates the activity of forebrain neural circuits involved in the control of energy dissipation. 相似文献
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José L.G. Galindo Mariola Macías José M.G. Molinillo Alba Muñoz-Suano Ascensión Torres Rosa M. Varela Francisco García-Cozar Francisco A. Macías 《Bioorganic & medicinal chemistry》2012,20(22):6662-6668
Bioactive natural products are a potential source of new pharmaceuticals since they offer new modes of action and more specific activities. The use of derivatization also enables the optimal structure for their biological activity to be determined. In this study several epoxycurcuphenol derivatives were synthesized. The substitution pattern on the aromatic and oxirane rings was varied along with that at the benzylic position and the length of the side chain was altered. These changes were made in order to gain a deeper understanding of the structural requirements for activity. The biological activities of these compounds were evaluated on the human leukemia cell line Jurkat using an antiproliferative assay. The activity results and structural requirements are discussed. 相似文献
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Piernicola Pedicini Rocchina Caivano Barbara A Jereczek-Fossa Lidia Strigari Barbara Vischioni Daniela Alterio Marta Cremonesi Francesca Botta Antonio Nappi Giuseppina Improta Giovanni Storto Alba Fiorentino Marcello Benassi Roberto Orecchia Vincenzo Fusco 《Theoretical biology & medical modelling》2012,9(1):1-1