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941.
Root phosphoenolpyruvate carboxylase and NAD-malic enzymes activity increase the ammonium-assimilating capacity in tomato 总被引:1,自引:0,他引:1
942.
Elena Chiricozzi Natalia Niemir Massimo Aureli Alessandro Magini Nicoletta Loberto Alessandro Prinetti Rosaria Bassi Alice Polchi Carla Emiliani Catherine Caillaud Sandro Sonnino 《Molecular neurobiology》2014,50(1):159-167
Sphingolipidoses are inherited genetic diseases due to mutations in genes encoding proteins involved in the lysosomal catabolism of sphingolipids. Despite a low incidence of each individual disease, altogether, the number of patients involved is relatively high and resolutive approaches for treatment are still lacking. The chaperone therapy is one of the latest pharmacological approaches to these storage diseases. This therapy allows the mutated protein to escape its natural removal and to increase its quantity in lysosomes, thus partially restoring the metabolic functions. Sandhoff disease is an autosomal recessive inherited disorder resulting from β-hexosaminidase deficiency and characterized by large accumulation of GM2 ganglioside in brain. No enzymatic replacement therapy is currently available, and the use of inhibitors of glycosphingolipid biosynthesis for substrate reduction therapy, although very promising, is associated with serious side effects. The chaperone pyrimethamine has been proposed as a very promising drug in those cases characterized by a residual enzyme activity. In this review, we report the effect of pyrimethamine on the recovery of β-hexosaminidase activity in cultured fibroblasts from Sandhoff patients. 相似文献
943.
Diogo Aparecido Lopes Silva Francisco Antonio Rocco Lahr Ana Laura Raymundo Pavan Yovana M. B. Saavedra Natalia Crespo Mendes Sabrina Rodrigues Sousa Roberta Sanches Aldo Roberto Ometto 《The International Journal of Life Cycle Assessment》2014,19(10):1767-1778
Purpose
Sugarcane bagasse is one of the main agro-industrial residues which can be used to produce wood-based panels. However, more investigations related to its environmental performance assessment are needed, focusing on questions such as: Does it provide environmental benefits? What are its main environmental impacts? Could it substitute wood as raw material? Accordingly, this paper presents a life cycle assessment (LCA) study of particle board manufactured with sugarcane bagasse residues.Methods
The cradle-to-gate assessment of 1 m3 of particle board made with sugarcane bagasse (PSB) considered three main subsystems: bagasse generation, bagasse distribution, and PSB production. For the inventory of PSB, dataset from two previous LCA studies related to the conventional particle board production and the ethanol life cycle for the Brazilian context were used. The allocation criterion for the bagasse generation subsystem was 9.08 % (economic base). The potential environmental impact phase was assessed by applying the CML and USEtox methods. PSB was compared with the conventional particle board manufactured in Brazil by the categories of the CML and USETox, and including land use indicators. Finally, two scenarios were analyzed to evaluate the influence of the allocation criteria and the consumption of sugarcane bagasse.Results and discussion
All hotspots identified by CML and USETox methods are mainly related to the PSB production subsystem (24–100 % of impacts) due to heavy fuel oil, electricity, and urea-formaldehyde resin supply chain. The bagasse generation subsystem was more relevant to the eutrophication category (75 % of impacts). The bagasse distribution subsystem was not relevant because the impacts on all categories were lower than 1 %. PSB can substitute the conventional particle board mainly because of its lower contribution to abiotic depletion and ecotoxicity. Regarding land use impacts, PSB showed lower values according to all indicators (38–40 % of all impacts), which is explained by the lower demand for land occupation in comparison to that of the traditional particle board.Conclusions
PSB can replace the traditional particle board due to its better environmental performance. The analysis of the economic allocation criterion was relevant only for the EP category, being important to reduce diesel and N-based fertilizers use during sugarcane cultivation. Regarding the influence of the sugarcane bagasse consumption, it is suggested that the sugarcane bagasse be mixed up to 75 % during particle board manufacturing so that good quality properties and environmental performance of panels can be provided. 相似文献944.
Vendela K. Lagerholm Edson Sandoval‐Castellanos Dorothee Ehrich Natalia I. Abramson Adam Nadachowski Daniela C. Kalthoff Mietje Germonpr Anders Angerbjrn John R. Stewart Love Daln 《Molecular ecology》2014,23(8):2060-2071
The Pleistocene glacial cycles resulted in significant changes in species distributions, and it has been discussed whether this caused increased rates of population divergence and speciation. One species that is likely to have evolved during the Pleistocene is the Norwegian lemming (Lemmus lemmus). However, the origin of this species, both in terms of when and from what ancestral taxon it evolved, has been difficult to ascertain. Here, we use ancient DNA recovered from lemming remains from a series of Late Pleistocene and Holocene sites to explore the species' evolutionary history. The results revealed considerable genetic differentiation between glacial and contemporary samples. Moreover, the analyses provided strong support for a divergence time prior to the Last Glacial Maximum (LGM), therefore likely ruling out a postglacial colonization of Scandinavia. Consequently, it appears that the Norwegian lemming evolved from a small population that survived the LGM in an ice‐free Scandinavian refugium. 相似文献
945.
Echinoderms, due to their outstanding potential for regeneration, are widely used as experimental models for research in regenerative biology. One of the main problems in this field concerns identification and characterization of cells responsible for the restoration of lost body parts and organs in adult animals. In this study, we analyze the probable candidates for this role in the starfish Asterias rubens L., namely, small coelomic epithelial cells with a high nuclear–cytoplasmic ratio that have the ability to proliferate. These cells are one of several cell types common to the coelomic epithelium (CE) and coelomic fluid (CF). They are analyzed with respect to morphology, proportion in the total cell pool, dynamics after injury and distribution between CE and CF. The results of whole-mount and scanning electron microscopy provide evidence that these small cells occupy a boundary position between CE and CF. Moreover, a novel subpopulation of CE cells is identified that is enriched (up to 50 %) with small epitheliocytes capable of migrating from CE into the CF. As shown in experiments with BrdU incorporation and anti-phospho-histone H3 antibody staining, small epitheliocytes cultured on laminin retain proliferative activity for at least 1 month and can form colony-like aggregates. Two types of small proliferating cells are distinguished by their behavior in culture: some cells remain attached to the substrate and form aggregates, while others detach from the substrate during culturing. The morphology of small epitheliocytes, their proliferative activity in vivo and in vitro and the ability to migrate suggest that they possess certain properties characteristic of stem cells. 相似文献
946.
Natalia Armas-Capote Juan Pérez-Yépez Pilar Martínez-Hidalgo Víctor Garzón-Machado Marcelino del Arco-Aguilar Encarna Velázquez Milagros León-Barrios 《Systematic and applied microbiology》2014
Cicer canariense is a threatened perennial wild chickpea endemic to the Canary Islands. In this study, rhizobia that nodulate this species in its natural habitats on La Palma (Canary Islands) were characterised. The genetic diversity and phylogeny were estimated by RAPD profiles, 16S-RFLP analysis and sequencing of the rrs, recA, glnII and nodC genes. 16S-RFLP grouped the isolates within the Mesorhizobium genus and distinguished nine different ribotypes. Four branches included minority ribotypes (3–5 isolates), whereas another five contained the predominant ribotypes that clustered with reference strains of M. tianshanense/M. gobiense/M. metallidurans, M. caraganae, M. opportunistum, M. ciceri and M. tamadayense. The sequences confirmed the RFLP groupings but resolved additional internal divergence within the M. caraganae group and outlined several potential novel species. The RAPD profiles showed a high diversity at the infraspecific level, except in the M. ciceri group. The nodC phylogeny resolved three symbiotic lineages. A small group of isolates had sequences identical to those of symbiovar ciceri and were only detected in M. ciceri isolates. Another group of sequences represented a novel symbiotic lineage that was associated with two particular chromosomal backgrounds. However, nodC sequences closely related to symbiovar loti predominated in most isolates, and they were detected in several chromosomal backgrounds corresponding to up to nine Mesorhizobium lineages. The results indicated that C. canariense is a promiscuous legume that can be nodulated by several rhizobial species and symbiotypes, which means it will be important to determine the combination of core and symbiotic genes that produce the most effective symbiosis. 相似文献
947.
Mikhail Vainshtein Natalia Belova Tatiana Kulakovskaya Natalia Suzina Vladimir Sorokin 《Journal of industrial microbiology & biotechnology》2014,41(4):657-663
Industrial production of magneto-sensitive nanoparticles, which can be used in the production of target drug delivery carriers, is a subject of interest for biotechnology and microbiology. Synthesis of these nanoparticles by microorganisms has been described only for bacterial species. At the same time, it is well known that yeasts can form various metal-containing nanoparticles used, for instance, in semiconductors, etc. This paper describes the first results of the biosynthesis of magneto-sensitive nanoparticles by yeasts. The organisms we used—Saccharomyces cerevisiae and Cryptococcus humicola—represented two different genera. Magneto-sensitive nanoparticles were synthesized at room temperature in bench-scale experiments. The study included transmission electron microscopy of the yeast cells and their energy dispersive spectrum analyses and revealed the presence of iron-containing nanoparticles. Both yeast cultures synthesized nanoparticles at high concentrations of dissolved iron. Electron microscopy showed that nanoparticles were associated mainly with the yeast cell wall. Formation of magneto-sensitive nanoparticles was studied under conditions of applied magnetic fields; a possible stimulating role of magnetic field is suggested. On the whole, the paper reports a novel approach to green biosynthesis of magneto-sensitive nanoparticles. 相似文献
948.
949.
Ariel A. Muñoz Jonathan Barichivich Duncan A. Christie Wouter Dorigo David Sauchyn Álvaro González‐Reyes Ricardo Villalba Antonio Lara Natalia Riquelme Mauro E. González 《Austral ecology》2014,39(2):158-169
Araucaria araucana (Araucaria) is a long‐lived conifer growing along a sharp west–east biophysical gradient in the Patagonian Andes. The patterns and climate drivers of Araucaria growth have typically been documented on the driest part of the gradient relying on correlations with meteorological records, but the lack of in situ soil moisture observations has precluded an assessment of the growth responses to soil moisture variability. Here, we use a network of 21 tree‐ring width chronologies to investigate the spatiotemporal patterns of tree growth through the entire gradient and evaluate their linkages with regional climate and satellite‐observed surface soil moisture variability. We found that temporal variations in tree growth are remarkably similar throughout the gradient and largely driven by soil moisture variability. The regional spatiotemporal pattern of tree growth was positively correlated with precipitation (r = 0.35 for January 1920–1974; P < 0.01) and predominantly negatively correlated with temperature (r = ?0.38 for January–March 1920–1974; P < 0.01) during the previous growing season. These correlations suggest a temporally lagged growth response to summer moisture that could be associated with known physiological carry‐over processes in conifers and to a response to moisture variability at deeper layers of the rooting zone. Notably, satellite observations revealed a previously unobserved response of Araucaria growth to summer surface soil moisture during the current rather than the previous growing season (r = 0.65 for 1979–2000; P < 0.05). This new response has a large spatial footprint across the mid‐latitudes of the South American continent (35°–45°S) and highlights the potential of Araucaria tree rings for palaeoclimatic applications. The strong moisture constraint on tree growth revealed by satellite observations suggests that projected summer drying during the coming decades may result in regional growth declines in Araucaria forests and other water‐limited ecosystems in the Patagonian Andes. 相似文献
950.
Alexey Tomilov Ahmed Bettaieb Kyoungmi Kim Sunil Sahdeo Natalia Tomilova Adam Lam Kevork Hagopian Michelle Connell Jennifer Fong Douglas Rowland Stephen Griffey Jon Ramsey Fawaz Haj Gino Cortopassi 《Aging cell》2014,13(6):1049-1058
Adipose tissue is an important metabolic organ that integrates a wide array of homeostatic processes and is crucial for whole‐body insulin sensitivity and energy metabolism. Brown adipose tissue (BAT) is a key thermogenic tissue with a well‐established role in energy expenditure. BAT dissipates energy and protects against both hypothermia and obesity. Thus, BAT stimulation therapy is a rational strategy for the looming pandemic of obesity, whose consequences and comorbidities have a huge impact on the aged. Shc‐deficient mice (ShcKO) were previously shown to be lean, insulin sensitive, and resistant to high‐fat diet and obesity. We investigated the contribution of BAT to this phenotype. Insulin‐dependent BAT glucose uptake was higher in ShcKO mice. Primary ShcKO BAT cells exhibited increased mitochondrial respiration; increased expression of several mitochondrial and lipid‐oxidative enzymes was observed in ShcKO BAT. Levels of brown fat‐specific markers of differentiation, UCP1, PRDM16, ELOVL3, and Cox8b, were higher in ShcKO BAT. In vitro, Shc knockdown in BAT cell line increased insulin sensitivity and metabolic activity. In vivo, pharmacological stimulation of ShcKO BAT resulted in higher energy expenditure. Conversely, pharmacological inhibition of BAT abolished the improved metabolic parameters, that is the increased insulin sensitivity and glucose tolerance of ShcKO mice. Similarly, in vitro Shc knockdown in BAT cell lines increased their expression of UCP1 and metabolic activity. These data suggest increased BAT activity significantly contributes to the improved metabolic phenotype of ShcKO mice. 相似文献