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61.
David Barros‐García Rafael Bañón Juan Carlos Arronte Lourdes Fernández‐Peralta Ramón García Alejandro de Carlos 《Zoologica scripta》2016,45(3):263-272
Notacanthiformes Goodrich, 1909, is an order of deep‐sea teleost fishes with a leptocephalus larval stage whose biology and systematics are not widely known. The aim of this work was to apply the DNA barcode standard, based on COI sequence variation, to the delimitation of the species of this order, which is composed by the families Halosauridae (halosaurus) and Notacanthidae (spiny eels). The sequence data used for the analyses were obtained from two sources: 71 samples collected during oceanographic surveys in the North Atlantic Ocean (including the rare species Lipogenys gillii Goode & Bean, 1895) and 95 sequences collected from the BOLD data set. The neighbor‐joining analysis of the barcodes was successful in identifying 96% of the specimens, representing 9 of 16 and 9 of 10 of the recognised species of halosaurus and spiny eels, respectively, including all the current genera. The comparison between the Atlantic and the BOLD data sets also flagged the possibility of occurrences of misidentification and cryptic species. A modern molecular tool like the DNA barcoding supports the previously morphological‐based systematics of the order Notacanthiformes and will provide better access to the taxonomic knowledge of these deep‐water fishes. 相似文献
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Paula M. Nogueira Rafael R. Assis Ana C. Torrecilhas Elvira M. Saraiva Natália L. Pessoa Marco A. Campos Eric F. Marialva Cláudia M. Ríos-Velasquez Felipe A. Pessoa Nágila F. Secundino Jer?nimo N. Rugani Elsa Nieves Salvatore J. Turco Maria N. Melo Rodrigo P. Soares 《PLoS neglected tropical diseases》2016,10(8)
The immunomodulatory properties of lipophosphoglycans (LPG) from New World species of Leishmania have been assessed in Leishmania infantum and Leishmania braziliensis, the causative agents of visceral and cutaneous leishmaniasis, respectively. This glycoconjugate is highly polymorphic among species with variation in sugars that branch off the conserved Gal(β1,4)Man(α1)-PO4 backbone of repeat units. Here, the immunomodulatory activity of LPGs from Leishmania amazonensis, the causative agent of diffuse cutaneous leishmaniasis, was evaluated in two strains from Brazil. One strain (PH8) was originally isolated from the sand fly and the other (Josefa) was isolated from a human case. The ability of purified LPGs from both strains was investigated during in vitro interaction with peritoneal murine macrophages and CHO cells and in vivo infection with Lutzomyia migonei. In peritoneal murine macrophages, the LPGs from both strains activated TLR4. Both LPGs equally activate MAPKs and the NF-κB inhibitor p-IκBα, but were not able to translocate NF-κB. In vivo experiments with sand flies showed that both stains were able to sustain infection in L. migonei. A preliminary biochemical analysis indicates intraspecies variation in the LPG sugar moieties. However, they did not result in different activation profiles of the innate immune system. Also those polymorphisms did not affect infectivity to the sand fly. 相似文献
64.
Handley Linda L.; Nevo Eviatar; Raven John A.; MartInez-Carrasco Rafael; Scrimgeour Charles M.; Pakniyat Hassan; Forster Brian P. 《Journal of experimental botany》1994,45(11):1661-1663
By combining the approaches of whole-shoot carbon discriminationand genetic analysis, we found that chromosome 4 controls potentialwater use efficiency ( 相似文献
65.
Heavy metals and arsenic uptake by wild vegetation in the Guadiamar river area after the toxic spill of the Aznalcóllar mine 总被引:4,自引:0,他引:4
Del Río M Font R Almela C Vélez D Montoro R De Haro Bailón A 《Journal of biotechnology》2002,98(1):125-137
On 25 April 1998, approximately 4.5 hm(3) of pyritic sludge, containing 5000 mg of As kg(-1) among other pollutants, was spilled into the Agrio and Guadiamar rivers and the surrounding agricultural areas (Aznalcóllar, Seville, Southern Spain). Many trace metals such as Pb, Cu, Zn, Cd, Tl, Sb and As reached the Do?ana National Park, the largest wetland area in Europe, affecting soils, different plant and animal species. In order to recuperate the affected lands by employing plants capable of accumulating high levels of contaminants in shoots, periodical field surveys have been made to identify the metal-tolerant species that are spontaneously growing in the polluted soils, and are able to uptake one or various of the contaminants. Among the 99 different plant species studied, Anchusa azurea, Beta vulgaris, Chamaemelum fuscatum, Convolvulus arvensis, Cynodon dactylon, Diplotaxis virgata, Erodium aethiopicum, Lavatera cretica, Malva nicaeensis, Silybum marianum and, above all, Amaranthus blitoides highlight as the most promising to be used in the remediation of the affected area. 相似文献
66.
Rafael Deliz-Aguirre Fakun Cao Fenja H.U. Gerpott Nichanok Auevechanichkul Mariam Chupanova YeVin Mun Elke Ziska Marcus J. Taylor 《The Journal of cell biology》2021,220(7)
A recurring feature of innate immune receptor signaling is the self-assembly of signaling proteins into oligomeric complexes. The Myddosome is an oligomeric complex that is required to transmit inflammatory signals from TLR/IL1Rs and consists of MyD88 and IRAK family kinases. However, the molecular basis for how Myddosome proteins self-assemble and regulate intracellular signaling remains poorly understood. Here, we developed a novel assay to analyze the spatiotemporal dynamics of IL1R and Myddosome signaling in live cells. We found that MyD88 oligomerization is inducible and initially reversible. Moreover, the formation of larger, stable oligomers consisting of more than four MyD88s triggers the sequential recruitment of IRAK4 and IRAK1. Notably, genetic knockout of IRAK4 enhanced MyD88 oligomerization, indicating that IRAK4 controls MyD88 oligomer size and growth. MyD88 oligomer size thus functions as a physical threshold to trigger downstream signaling. These results provide a mechanistic basis for how protein oligomerization might function in cell signaling pathways. 相似文献
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68.
Pujadas M Pichini S Poudevida S Menoyo E Zuccaro P Farré M de la Torre R 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》2003,798(2):249-255
A procedure based on gas chromatography-mass spectrometry (GC-MS) is described for the determination of amphetamine, methamphetamine, 3,4-methylenedioxyamphetamine (MDA), 3,4-methylenedioxymethamphetamine (MDMA, ecstasy), 3,4-methylenedioxyethylamphetamine (MDE or MDEA) and N-methyl-1-(3,4-methylenedioxyphenyl)-2-butanamine (MBDB) in hair. Hair samples were digested with 1 M sodium sulfide at 37 degrees C (by shaking for 3 h and was kept at room temperature overnight), and extracted with two sequential extraction procedures: liquid-liquid extraction with tert-butyl methyl ether and solid-phase extraction with Bond-Elut Certify columns. Extracted analytes were derivatised with N-methyl-bis(trifluoroacetamide), separated by a 5% phenylmethylsilicone column and determined by a mass spectrometer detector in selected ion monitoring mode. A good reproducibility (intra-assay R.S.D.=1.5-15.7%), accuracy (intra-assay error = 2.0-11.7%) and sensitivity (LOD=0.03-0.08 ng/mg hair) were attained. The method was successfully applied to the analysis of the proximal (1 cm) hair segment to assess recent self-reported use in "ecstasy" consumers. Otherwise, further studies are needed to validate methodology developed in case of amphetamine consumption. 相似文献
69.
In situ hybridization was used to determine the physical location of the Hsp70 genes in salivary polytene chromosomes of Anopheles darlingi from Manaus and Macapá, Brazil, and to assess the usefulness of the Hsp70 locus as a genetic marker in A. darlingi populations. In both populations, the double markings corresponding to the Hsp70-12A and Hsp70-14A genes were located on the right arm of chromosome 2. The Hsp70 locus was considered to be an excellent marker for studying chromosomal evolution and relationships among A. darlingi populations. 相似文献
70.