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101.
Pedro Len‐Lobos Marcela A. Bustamante‐Snchez Cara R. Nelson Diego Alarcn Rodrigo Hasbún Michael Way Hugh W. Pritchard Juan J. Armesto 《Restoration Ecology》2020,28(2):277-281
We argue that the need for a quality seed supply chain is a major bottleneck for the restoration of Chile's native ecosystems, thus supplementing the list of bottlenecks proposed by Bannister et al. in 2018. Specifically, there is a need for defining seed transfer zones, developing standards and capacities for properly collecting and storing seeds, reducing information gaps on seed physiology and longevity, and implementing an efficient seed supply chain with certification of seed origin and quality. Without such capacities, countries are unlikely to meet their restoration commitments. Although we focus on bottlenecks in Chile, the issues we raise are relevant to other countries and thus the global agenda for ecological restoration. 相似文献
102.
Recent collections and the type specimen of Marasmiellus juniperinus, the type species of the genus, were examined. Phylogenetic placement, based on ribosomal large subunit (LSU) and internally transcribed spacer (ITS) sequences, is within the lentinuloid clade, nested among Gymnopus taxa. This placement dictates genus name usage and phylogenetic position of other putative species of Marasmiellus. The mating system is tetrapolar. 相似文献
103.
104.
ATP (1 mM) increased the phospholipase D (PLD) activity of rat submandibular gland (RSMG) ductal cells in a concentration-dependent and calcium-sensitive manner. The response to ATP was reproduced by benzoylbenzoyl-ATP (Bz-ATP, 100 microM) and also partly by adenosine 5'-(gamma-thio)triphosphate (ATPgammaS, 1 mM). A similar stimulation was observed in control mice (P2X7R+/+ mice) but not in mice lacking the P2X7 receptors (P2X7R-/- mice). Oxidized ATP and Coomassie blue or the addition of magnesium or nickel to the incubation medium inhibited the response to ATP. The stimulation of PLD by purinergic agonist was inhibited by about 50% by calphostin C and chelerythrine, two protein kinase C (PKC) inhibitors. The stimulation of PLD by Bz-ATP and by o-tetradecanoylphorbol 13-acetate (TPA), a phorbol ester which activates PKC, were not additive.From these results we can conclude that the activation of P2X7 receptors in RSMG ductal cells is coupled to the activation of a PLD. This activation is partly mediated by protein kinase C. 相似文献
105.
106.
Da Silva-Grigoletto ME Fernández JM de Sá CA Gómez-Puerto JR Vaamonde D Pérez-Jiménez F 《Journal of strength and conditioning research / National Strength & Conditioning Association》2010,24(12):3334-3342
The addition of fructose (F) to a glucose (G) supplement may modify the metabolic response during exercise; however, its effect on perceived exertion (PE) and its influence on postprandial metabolism have not been jointly studied in different types of exercise. This study sought to assess the acute effects of F addition to a G supplement on PE and on the postprandial metabolic response during a single bout of either strength exercise (SE) or endurance exercise (EE). Twenty physically trained men ingested an oral dose of G or GF 15 minutes before starting a 30-minute session of SE (10 sets of 10 repetitions of half squat) or EE (cycling). The combination resulted in 4 randomized interventions in a crossover design in which all subjects performed all experimental conditions: G + SE, GF + SE, G + EE, and GF + SE. Perceived exertion, heart rate (HR), G, insulin, lactate, and urinary catecholamine levels were measured before exercise, during the exercise, and during acute recovery. Perceived exertion during exercise was lower for GF than for G during SE and EE (mean ± SD; 8.95 ± 0.62 vs. 9.26 ± 0.65, p < 0.05 and 7.47 ± 0.84 vs. 7.74 ± 0.93, p < 0.05, respectively). The glycemic peak in GF + SE was lower than in G + SE (p < 0.05), and there was a second peak during recovery (p < 0.05), whereas in EE, no difference in blood G levels was noted between G and GF supplements. Moreover, HR, urinary adrenalin, and noradrenalin were lower in GF than in G (p < 0.05), though only for EE. The results showed that PE is positively affected by GF supplementation for both SE and EE and thus may be a useful dietary strategy for helping to achieve higher training loads. 相似文献
107.
Functional Inhibition of Aquaporin‐3 With a Gold‐Based Compound Induces Blockage of Cell Proliferation 下载免费PDF全文
108.
Dhaval P. Bhatt C. Allie Mills Kristin A. Anderson Brbara J. Henriques Tnia G. Lucas Sara Francisco Juan Liu Olga R. Ilkayeva Alexander E. Adams Shreyas R. Kulkarni Donald S. Backos Michael B. Major Paul A. Grimsrud Cludio M. Gomes Matthew D. Hirschey 《The Journal of biological chemistry》2022,298(4)
A wide range of protein acyl modifications has been identified on enzymes across various metabolic processes; however, the impact of these modifications remains poorly understood. Protein glutarylation is a recently identified modification that can be nonenzymatically driven by glutaryl-CoA. In mammalian systems, this unique metabolite is only produced in the lysine and tryptophan oxidative pathways. To better understand the biology of protein glutarylation, we studied the relationship between enzymes within the lysine/tryptophan catabolic pathways, protein glutarylation, and regulation by the deglutarylating enzyme sirtuin 5 (SIRT5). Here, we identify glutarylation on the lysine oxidation pathway enzyme glutaryl-CoA dehydrogenase (GCDH) and show increased GCDH glutarylation when glutaryl-CoA production is stimulated by lysine catabolism. Our data reveal that glutarylation of GCDH impacts its function, ultimately decreasing lysine oxidation. We also demonstrate the ability of SIRT5 to deglutarylate GCDH, restoring its enzymatic activity. Finally, metabolomic and bioinformatic analyses indicate an expanded role for SIRT5 in regulating amino acid metabolism. Together, these data support a feedback loop model within the lysine/tryptophan oxidation pathway in which glutaryl-CoA is produced, in turn inhibiting GCDH function via glutaryl modification of GCDH lysine residues and can be relieved by SIRT5 deacylation activity. 相似文献
109.
Ana C. Santos Joana Cunha F. Veiga A. Cordeiro-da-Silva Antonio J. Ribeiro 《Carbohydrate polymers》2013
Alginate-dextran sulfate (ADS) microgel has been used to protect insulin from gastrointestinal attack and as a carrier to promote insulin permeation through intestinal epithelium. The throughput of ADS submicron particles generation by emulsification/internal gelation is limited by its wide size distribution. 相似文献
110.
Species complexes - groups of closely related species in which intraspecific and interspecific variability overlap - have generated considerable interest and study. Frequently, members of a species complex do not have complete reproductive isolation; therefore, the complex may go through extensive gene flow. In the Caribbean Sea, some encrusting and excavating sponges of the genus Cliona (Porifera, Hadromerida, Clionaidae) are grouped within the great "Cliona viridis" complex because of their morphological similarities. This study examined the evolutionary relationships of the Caribbean members of this complex (C. caribbaea, C. tenuis, C. aprica and C. varians) and related taxa based on nuclear (ITS1 and ITS2) and mitochondrial (3' end of ND6) DNA sequences. The intragenomic ITS variation and its secondary structures were evaluated using a mixed approach of Denaturing Gradient Gel Electrophoresis (DGGE), DNA sequencing and secondary structure prediction. Considerable intragenomic variation was found in all the species, with apparently functional ITS1 and ITS2 secondary structures. Despite the subtle but clear morphological differentiation in these excavating sponges, the intragenomic copies of C. caribbaea, C. tenuis and C. aprica had a polyphyletic placement in the ITS1 and ITS2 genealogies and very low divergence. Therefore, it is clear that these species constitute a species complex (herein called Ct-complex). Genetic distances within the Ct-complex revealed that an important part of the interspecific variation overlapped with intraspecific variation, suggesting either incomplete lineage sorting or extensive gene flow. In contrast, C. varians and an unidentified "Pione" species emerged as monophyletic clades, being the closest sister groups to the Ct-complex. Additionally, our results support that C. laticavicola and C. delitrix conform a monophyletic group, but absence of reciprocal monophyly in these species suggests they may be life stages or ecophenotypes of a single species or they have diverged recently. Our work showed that the 3' end of the ND6 mitochondrial gene was highly conserved and not suitable for phylogenetic analysis at the interspecific level. 相似文献