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631.
Adam C. Swensen Jordan G. Finnell Catalina Matias Andrew J. Gross John T. Prince Richard K. Watt John C. Price 《Analytical biochemistry》2017
Hepcidin is a small cysteine-rich signaling peptide that regulates blood serum iron concentrations [1–4]. Patients with chronic inflammation are known to have elevated levels of hepcidin in their blood and urine and often suffer from anemia as a result [5–10]. Measuring and quantifying the amount of active hepcidin in blood and urine can help to determine the cause and severity of the anemia thereby helping physicians determine the correct course of treatment [11–16]. We have developed a simple technique to isolate, chemically modify, and concentrate hepcidin from blood and urine coupled to high-pressure liquid chromatography mass spectrometry that can accurately and reproducibly measure and quantify the active hormone. 相似文献
632.
Paola Di Leo Lira Catalina M. van Baren Simon López Ana Molina Cecilia Heit Carmen Viturro Marina P. de Lampasona Cesar A. Catalán Arnaldo Bandoni 《化学与生物多样性》2013,10(2):251-261
The aerial parts of lemon verbena (Aloysia citriodora Paláu ) are worldwide used due to their medicinal and aromatic properties. The essential‐oil and acteoside contents have been proposed as the main quality markers for their pharmacological and organoleptic features. The northwestern region of Argentina has been repeatedly proposed as the place of origin for this species. For this reason, the essential‐oil yields and chemical compositions of leaves of 25 populations of lemon verbena from both wild collections and experimental crops from this region were studied. Plants from six different collections were subsequently grown on the same experimental parcel located at Cerrillos, Salta province, during more than seven years. In addition, the acteoside contents determined in all the samples collected in 2010 showed significant variations (from 0.5 to 4.0%). Large differences were observed in the essential‐oil composition and yields, which ranged from 0.4 to 2.1% (v/w). Nevertheless, most of the samples complied with the European Pharmacopoeia specifications. A remarkable chemical diversity with at least four clearly defined chemotypes was detected in this region. Therefore, it would be urgent to encourage actions to protect these genotypes of lemon verbena in the northwestern Argentina. 相似文献
633.
Catalina Sanz María I Alvarez Margarita Orejas Antonio Velayos Arturo P Eslava Ernesto P Benito 《European journal of biochemistry》2002,269(3):902-908
The Phycomyces blakesleeanus wild-type is yellow, because it accumulates beta-carotene as the main carotenoid. A new carotenoid mutant of this fungus (A486) was isolated, after treatment with ethyl methane sulfonate (EMS), showing a whitish coloration. It accumulates large amounts of phytoene, small quantities of phytofluene, zeta-carotene and neurosporene, in decreasing amounts, and traces of beta-carotene. This phenotype indicates that it carries a leaky mutation affecting the enzyme phytoene dehydrogenase (EC 1.3.-.-), which is specified by the gene carB. Biochemical analysis of heterokaryons showed that mutant A486 complements two previously characterized carB mutants, C5 (carB10) and S442 (carB401). Sequence analysis of the carB gene genomic copy from these three strains revealed that they are all altered in the gene carB, giving information about the nature of the mutation in each carB mutant allele. The interallelic complementation provides evidence for the multimeric organization of the P. blakesleeanus phytoene dehydrogenase. 相似文献
634.
Whitehead Darren A. Gayford Joel H. Hoyos Edgar Mauricio Shorter Nikolai Madland Galván-Magaña Felipe Ketchum James T. 《Environmental Biology of Fishes》2022,105(7):961-961
Environmental Biology of Fishes - 相似文献
635.
Daniele De Corte Simone Muck Johanna Tiroch Catalina Mena Gerhard J. Herndl Eva Sintes 《Environmental microbiology》2021,23(11):7152-7167
Only about 10%–30% of the organic matter produced in the epipelagic layers reaches the dark ocean. Under these limiting conditions, reduced inorganic substrates might be used as an energy source to fuel prokaryotic chemoautotrophic and/or mixotrophic activity. The aprA gene encodes the alpha subunit of the adenosine-5′-phosphosulfate (APS) reductase, present in sulfate-reducing (SRP) and sulfur-oxidizing prokaryotes (SOP). The sulfur-oxidizing pathway can be coupled to inorganic carbon fixation via the Calvin–Benson–Bassham cycle. The abundances of aprA and cbbM, encoding RuBisCO form II (the key CO2 fixing enzyme), were determined over the entire water column along a latitudinal transect in the Atlantic from 64°N to 50°S covering six oceanic provinces. The abundance of aprA and cbbM genes significantly increased with depth reaching the highest abundances in meso- and upper bathypelagic layers. The contribution of cells containing these genes also increased from mesotrophic towards oligotrophic provinces, suggesting that under nutrient limiting conditions alternative energy sources are advantageous. However, the aprA/cbbM ratios indicated that only a fraction of the SOP is associated with inorganic carbon fixation. The aprA harbouring prokaryotic community was dominated by Pelagibacterales in surface and mesopelagic waters, while Candidatus Thioglobus, Chromatiales and the Deltaproteobacterium_SCGC dominated the bathypelagic realm. Noticeably, the contribution of the SRP to the prokaryotic community harbouring aprA gene was low, suggesting a major utilization of inorganic sulfur compounds either as an energy source (occasionally coupled with inorganic carbon fixation) or in biosynthesis pathways. 相似文献
636.
637.
Whitehead Darren A. Gayford Joel H. Hoyos Edgar Mauricio Shorter Nikolai Madland Galván-Magaña Felipe Ketchum James T. 《Environmental Biology of Fishes》2022,105(7):953-960
Environmental Biology of Fishes - The silky shark (Carcharhinus falciformis) is a pelagic carcharhiniform shark species distributed globally in tropical and subtropical oceans. In this study, we... 相似文献
638.
Seeds ofDactyloctenium Willd. andEleusine Gaertn. may be distinguished from each other by spermoderm patterns.Dactyloctenium seeds are transversed by ridges crossed by wavy lines forming a verrucated, reticulate pattern.Eleusine seeds have a pitted, tuberculate spermoderm pattern. 相似文献
639.
Catalina VelascoCharpentier Felipe PizarroMora Nelso P. Navarro Nelson Valdivia 《Ecology and evolution》2021,11(3):1214
Habitat complexity is one of the most important factors modulating species diversity. This feature comprises several interrelated attributes, such as number, size, and spatial arrangement of complexity‐forming elements. However, the separate and joint effects of these attributes on diversity and community structure are still not well understood. Here, we assess the relationships between several structural‐complexity attributes of the subantarctic kelp Lessonia flavicans and species richness, total abundance, and structure of kelp‐associated macrobenthic communities. We predicted that longer thalli and larger holdfasts favor greater species richness and total abundance of invertebrate organisms. To test the prediction, an observational sampling program was established in two sites of the Strait of Magellan. Uni‐ and multivariate analyses revealed both positive and negative effects of kelp structural‐complexity attributes on diversity. Holdfast diameter and maximum frond length, followed by thallus wet weight, had the strongest positive fits to species richness and total abundance; the number of stipes, on the other hand, was negatively associated with both response variables. Longer fronds were associated with greater abundances of spirorbid polychaetes. Larger holdfasts supported larger abundances of Nereididae and Terebelidae polychaetes and the limpet Nacella mytilina. Contrarily, kelps with longer fronds and more stipes supported fewer amphipods. In this way, we demonstrate that different dimensions of habitat complexity can have contrasting effects on diversity and community structure, highlighting the fundamental role of multiple dimensions of kelp habitat complexity for local biodiversity. 相似文献
640.
Mariam Hachimi Catalina Grabowski Silvia Campanario Gonzalo Herranz Gabriel Baonza Juan M. Serrador Sergio Gomez-Lopez Maria D. Barea Minerva Bosch-Fortea Darren Gilmour Michel Bagnat Alejo E. Rodriguez-Fraticelli Fernando Martin-Belmonte 《Current biology : CB》2021,31(4):696-706.e9
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