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51.
Alberto Leyva Abrisleida Franco Tatiana González Julio C Sánchez Ivette López Déborah Geada Neyda Hernández Margela Monta?és Iliana Delgado Rodolfo Valdés 《Biologicals》2007,35(1):19-25
An enzyme-linked immunosorbent assay to quantify the mAb CB.Hep-1 during downstream purification process was standardized and validated. This assay is characterized by a short time of incubation at high temperature, allowing the detection of this antibody with high specificity and sensitivity. Detection of antigen-antibody reaction was achieved using a horseradish peroxidase conjugated anti-mouse IgG whose enzyme activity was revealed with o-phenylenediamine substrate. The immunoassay is linear in a range between 3.12 and 50 ng/mL, with a recovery of 98.55-107.62%. According to results, it is possible to estimate the mAb CB.Hep-1 concentration with high precision and reproducibility. The intra- and interassay coefficient of variation ranged from 0.25 to 8.64% and 1.84 to 9.43%, respectively. Significant differences were not observed in the plant-derived antibody quantification by HRP-ELISA and PhoA-ELISA (n=18), demonstrating that plant endogenous peroxidases do not produce interferences in the quantification of this molecule. Therefore, both antibodies can be tested with the same immunoassay with high precision, specificity and accuracy during their respective purification processes without interference of the buffers and sample characteristics. 相似文献
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Xanthomatous infiltration of tendons is a clinical feature common to many cases of hyperlipidemia. The xanthomas can be detected and only grossly assessed by palpation. This report describes a radiological technique used to assess these lesions at the Achilles tendon level. The “mammography technique” applied to the study of Achilles tendons was used in 32 normolipemic subjects and 32 hyperlipidemic patients. Both tendons could be observed in their entire length and their thickness, greatly increased in xanthomatosis, could be accurately measured. The results of this survey suggest that the radiological approach may provide a useful tool for the routine evaluation and follow-up of tendon xanthomas. 相似文献
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George Olah Stuart H. M. Butchart Andy Symes Iliana Medina Guzmán Ross Cunningham Donald J. Brightsmith Robert Heinsohn 《Biodiversity and Conservation》2016,25(2):205-223
Parrots (Psittaciformes) are among the most threatened bird orders with 28 % (111 of 398) of extant species classified as threatened under IUCN criteria. We confirmed that parrots have a lower Red List Index (higher aggregate extinction risk) than other comparable bird groups, and modeled the factors associated with extinction risk. Our analyses included intrinsic biological, life history and ecological attributes, external anthropogenic threats, and socio-economic variables associated with the countries where the parrot species occur, while we controlled for phylogenetic dependence among species. We found that the likelihood of parrot species being classified as threatened was less for species with larger historical distribution size, but was greater for species with high forest dependency, large body size, long generation time, and greater proportion of the human population living in urban areas in the countries encompassing the parrots’ home ranges. The severity of extinction risk (from vulnerable to critically endangered) was positively related to the per capita gross domestic product (GDP) of the countries of occurrence, endemism to a single country, and lower for species used as pets. A disproportionate number of 16 extinct parrot species were endemic to islands and single countries, and were large bodied, habitat specialists. Agriculture, hunting, trapping, and logging are the most frequent threats to parrots worldwide, with variation in importance among regions. We use multiple methods to rank countries with disproportionately high numbers of threatened parrot species. Our results promote understanding of global and regional factors associated with endangerment in this highly threatened taxonomic group, and will enhance the prioritization of conservation actions. 相似文献
54.
Christelle Dutilleul Iliana Ribeiro Nathalie Blanc Cynthia D. Nezames Xing Wang Deng Piotr Zglobicki Ana María Palacio Barrera Lucia Atehortùa Martine Courtois Valérie Labas Nathalie Giglioli‐Guivarc'h Eric Ducos 《Plant, cell & environment》2016,39(1):185-198
The tagging‐via‐substrate approach designed for the capture of mammal prenylated proteins was adapted to Arabidopsis cell culture. In this way, proteins are in vivo tagged with an azide‐modified farnesyl moiety and captured thanks to biotin alkyne Click‐iT® chemistry with further streptavidin‐affinity chromatography. Mass spectrometry analyses identified four small GTPases and ASG2 (ALTERED SEED GERMINATION 2), a protein previously associated to the seed germination gene network. ASG2 is a conserved protein in plants and displays a unique feature that associates WD40 domains and tetratricopeptide repeats. Additionally, we show that ASG2 has a C‐terminal CaaX‐box that is farnesylated in vitro. Protoplast transfections using CaaX prenyltransferase mutants show that farnesylation provokes ASG2 nucleus exclusion. Moreover, ASG2 interacts with DDB1 (DAMAGE DNA BINDING protein 1), and the subcellular localization of this complex depends on ASG2 farnesylation status. Finally, germination and root elongation experiments reveal that asg2 and the farnesyltransferase mutant era1 (ENHANCED RESPONSE TO ABSCISIC ACID (ABA) 1) behave in similar manners when exposed to ABA or salt stress. To our knowledge, ASG2 is the first farnesylated DWD (DDB1 binding WD40) protein related to ABA response in Arabidopsis that may be linked to era1 phenotypes. 相似文献
55.
Alan Xiangdong Wang Jie Chen Qian Zhao Li-Qiang Sun Jacques Friborg Fei Yu Dennis Hernandez Andrew C. Good Herbert E. Klei Ramkumar Rajamani Kathy Mosure Jay O. Knipe Danshi Li Jialong Zhu Paul C. Levesque Fiona McPhee Nicholas A. Meanwell Paul M. Scola 《Bioorganic & medicinal chemistry letters》2017,27(3):590-596
The design and synthesis of a series of tripeptide acylsulfonamides as potent inhibitors of the HCV NS3/4A serine protease is described. These analogues house a C4 aryl, C4 hydroxy-proline at the S2 position of the tripeptide scaffold. Information relating to structure-activity relationships as well as the pharmacokinetic and cardiovascular profiles of these analogues is provided. 相似文献
56.
Distinct sources of gene flow produce contrasting population genetic dynamics at different range boundaries of a Choristoneura budworm
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Gwylim S. Blackburn Bryan M. T. Brunet Kevin Muirhead Michel Cusson Catherine Béliveau Roger C. Levesque Lisa M. Lumley Felix A. H. Sperling 《Molecular ecology》2017,26(23):6666-6684
Populations are often exposed to multiple sources of gene flow, but accounts are lacking of the population genetic dynamics that result from these interactions or their effects on local evolution. Using a genomic clines framework applied to 1,195 single nucleotide polymorphisms, we documented genomewide, locus‐specific patterns of introgression between Choristoneura occidentalis biennis spruce budworms and two ecologically divergent relatives, C. o. occidentalis and Choristoneura fumiferana, that it interacts with at alternate boundaries of its range. We observe contrasting hybrid indexes between the two hybrid zones, no overlap in “gene‐flow outliers” (clines showing relatively extreme extents or rates of locus‐specific introgression) and variable linkage disequilibrium among those outliers. At the same time, correlated genomewide rates of introgression between zones suggest the presence of processes common to both boundaries. These findings highlight the contrasting population genetic dynamics that can occur at separate frontiers of a single population, while also suggesting that shared patterns may frequently accompany cases of divergence‐with‐gene‐flow that involve a lineage in common. Our results point to potentially complex evolutionary outcomes for populations experiencing multiple sources of gene flow. 相似文献
57.
Finlay HJ Lloyd J Nyman M Conder ML West T Levesque P Atwal K 《Bioorganic & medicinal chemistry letters》2008,18(8):2714-2718
The design and synthesis of a series of highly functionalized pyrano-[2,3b]-pyridines is described. These compounds were assayed for their ability to block the I(Kur) channel encoded by the gene hKV1.5 in patch-clamped L-929 cells. Six of the compounds in this series showed sub-micromolar activity, the most potent being 4-(4-ethyl-benzenesulfonylamino)-3-hydroxy-2,2-dimethyl-3,4-dihydro-2H-pyrano[2,3b]-pyridine-6-carboxylic acid ethyl-phenyl-amide with an IC(50) of 378 nM. 相似文献
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Muscle glycogen depletion has been proposed as one of the main causes of fatigue during exercise. However, few studies have addressed the contribution of liver glycogen to exercise performance. Using a low-intensity running protocol, here, we analyzed exercise capacity in mice overexpressing protein targeting to glycogen (PTG) specifically in the liver (PTGOE mice), which show a high concentration of glycogen in this organ. PTGOE mice showed improved exercise capacity, as determined by the distance covered and time ran in an extenuating endurance exercise, compared with control mice. Moreover, fasting decreased exercise capacity in control mice but not in PTGOE mice. After exercise, liver glycogen stores were totally depleted in control mice, but PTGOE mice maintained significant glycogen levels even in fasting conditions. In addition, PTGOE mice displayed an increased hepatic energy state after exercise compared with control mice. Exercise caused a reduction in the blood glucose concentration in control mice that was less pronounced in PTGOE mice. No changes were found in the levels of blood lactate, plasma free fatty acids, or β-hydroxybutyrate. Plasma glucagon was elevated after exercise in control mice, but not in PTGOE mice. Exercise-induced changes in skeletal muscle were similar in both genotypes. These results identify hepatic glycogen as a key regulator of endurance capacity in mice, an effect that may be exerted through the maintenance of blood glucose levels. 相似文献