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1.
The cellular energy and biomass demands of cancer drive a complex dynamic between uptake of extracellular FAs and their de novo synthesis. Given that oxidation of de novo synthesized FAs for energy would result in net-energy loss, there is an implication that FAs from these two sources must have distinct metabolic fates; however, hitherto, all FAs have been considered part of a common pool. To probe potential metabolic partitioning of cellular FAs, cancer cells were supplemented with stable isotope-labeled FAs. Structural analysis of the resulting glycerophospholipids revealed that labeled FAs from uptake were largely incorporated to canonical (sn-) positions on the glycerol backbone. Surprisingly, labeled FA uptake also disrupted canonical isomer patterns of the unlabeled lipidome and induced repartitioning of n-3 and n-6 PUFAs into glycerophospholipid classes. These structural changes support the existence of differences in the metabolic fates of FAs derived from uptake or de novo sources and demonstrate unique signaling and remodeling behaviors usually hidden from conventional lipidomics.  相似文献   
2.
Lengthening the aesthetically short nose   总被引:2,自引:0,他引:2  
An aesthetically short nose is defined as a developmental deformity in which the nose appears foreshortened. It is characterized by a decreased distance from the nasofrontal angle (NFA) to the tip-defining points (TDP) and an increased nasolabial angle with increased nostril show. A method is described and illustrated for lengthening the aesthetically short nose by rotating the nasal tip in an inferior direction. This rotation results in an actual lengthening, as well as an illusion of lengthening of the nose.  相似文献   
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Zusammenfassung Entlang eines Transekts über die Meerenge von Gibraltar wurde der Tagzug von Sturmschwalben von August bis Dezember erfaßt. Für einen Durchzug im Mittelmeer brütender Sturmschwalben konnten keine Hinweise gefunden werden; die meisten Vögel scheinen Angehörige der atlantischen Population zu sein. Die Präsenz ist im Oktober/November am höchsten, wenn südwärts ziehende atlantische Brutvögel die Breiten der Straße von Gibraltar erreichen. Insgesamt machten die ins Mittelmeer einfliegenden Vögel 83 % der nach Osten oder Westen fliegenden aus; Schätzungen ergaben für den Tagzug, daß nur 1100–1700 Sturmschwalben das Mittelmeer verließen (hingegen 6300–9500 einflogen). Die mediterrane Brutpopulation ist auf 12 000 Brutpaare zu schätzen.
Autumn migration of the Storm PetrelHydrobates plelagicus through the Strait of Gibraltar
Storm petrels were recorded along a transect line in the Strait of Gibraltar from August to the middle of November and in December. No hint for migration of the Mediterranean population through the Strait could be revealed. The presence of Storm Petrels is enhanced in October/November. Throughout autumn about 82 % of the Storm Petrels steadily flying east or west flew east. Estimates yield only 1100–1700 storm petrels leaving, but 6300–9500 entering the Mediterranean during daylight, while about 12,000 pairs are known to breed in the Mediterranean.
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Porcine circovirus type 2 (PCV‐2) is the main causative agent associated with a group of diseases collectively known as porcine circovirus‐associated disease (PCAD). There is a significant economic strain on the global swine industry due to PCAD and the production of commercial PCV‐2 vaccines is expensive. Plant expression systems are increasingly regarded as a viable technology to produce recombinant proteins for use as pharmaceutical agents and vaccines. However, successful production and purification of PCV‐2 capsid protein (CP) from plants is an essential first step towards the goal of a plant‐produced PCV‐2 vaccine candidate. In this study, the PCV‐2 CP was transiently expressed in Nicotiana benthamiana plants via agroinfiltration and PCV‐2 CP was successfully purified using sucrose gradient ultracentrifugation. The CP self‐assembled into virus‐like particles (VLPs) resembling native virions and up to 6.5 mg of VLPs could be purified from 1 kg of leaf wet weight. Mice immunized with the plant‐produced PCV‐2 VLPs elicited specific antibody responses to PCV‐2 CP. This is the first report describing the expression of PCV‐2 CP in plants, the confirmation of its assembly into VLPs and the demonstration of their use to elicit a strong immune response in a mammalian model.  相似文献   
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The Bcl‐2 inhibitor FKBP38 is regulated by the Ca2+‐sensor calmodulin (CaM). Here we show a hitherto unknown low‐affinity cation‐binding site in the FKBP domain of FKBP38, which may afford an additional level of regulation based on electrostatic interactions. Fluorescence titration experiments indicate that in particular the physiologically relevant Ca2+ ion binds to this site. NMR‐based chemical shift perturbation data locate this cation‐interaction site within the β5–α1 loop (Leu90–Ile96) of the FKBP domain, which contains the acidic Asp92 and Asp94 side‐chains. Binding constants were subsequently determined for K+, Mg2+, Ca2+, and La3+, indicating that the net charge and the radius of the ion influences the binding interaction. X‐ray diffraction data furthermore show that the conformation of the β5–α1 loop is influenced by the presence of a positively charged guanidinium group belonging to a neighboring FKBP38 molecule in the crystal lattice. The position of the cation‐binding site has been further elucidated based on pseudocontact shift data obtained by NMR via titration with Tb3+. Elimination of the Ca2+‐binding capacity by substitution of the respective aspartate residues in a D92N/D94N double‐substituted variant reduces the Bcl‐2 affinity of the FKBP3835–153/CaM complex to the same degree as the presence of Ca2+ in the wild‐type protein. Hence, this charge‐sensitive site in the FKBP domain participates in the regulation of FKBP38 function by enabling electrostatic interactions with ligand proteins and/or salt ions such as Ca2+. Copyright © 2010 John Wiley & Sons, Ltd.  相似文献   
8.
Two-dimensional gel electrophoresis was used to screen spring barley cultivars for differences in seed protein profiles. In parallel, 72 microsatellite (simple sequence repeat (SSR)) markers and 11 malting quality parameters were analysed for each cultivar. Over 60 protein spots displayed cultivar variation, including peroxidases, serpins and proteins with unknown functions. Cultivars were clustered based on the spot variation matrix. Cultivars with superior malting quality grouped together, indicating malting quality to be more closely correlated with seed proteomes than with SSR profiles. Mass spectrometry showed that some spot variations were caused by amino acid differences encoded by single nucleotide polymorphisms (SNPs). Coding SNPs were validated by mass spectrometry, expressed sequence tag and 2D gel data. Coding SNPs can alter function of affected proteins and may thus represent a link between cultivar traits, proteome and genome. Proteome analysis of doubled haploid lines derived from a cross between a malting (Scarlett) and a feed cultivar (Meltan) enabled genetic localisation of protein phenotypes represented by 48 spot variations, involving e.g. peroxidases, serpins, α-amylase/trypsin inhibitors, peroxiredoxin and a small heat shock protein, in relation to markers on the chromosome map. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.  相似文献   
9.
We aimed to clarify phylogenetic relationships within the pantropical genus Diospyros (Ebenaceae sensu lato), and ascertain biogeographical patterns in the New Caledonian endemic species. We used DNA sequences from eight plastid regions (rbcL, atpB, matK, ndhF, trnK intron, trnL intron, trnL-trnF spacer, and trnS-trnG spacer) and included 149 accessions representing 119 Diospyros species in our analysis. Results from this study confirmed the monophyly of Diospyros with good support and provided a clearer picture of the relationships within the genus than in previous studies. Evidence from phylogenetic analyses suggests that Diospyros colonized New Caledonia multiple times. The four lineages of Diospyros in New Caledonia also differ in their degree of diversification. The molecular data indicate that one lineage is paleoendemic and derived from an ancient Australian species. The other three lineages are more closely related to several Southeast Asian species; two of them are neoendemics, and one has radiated rapidly and recently.  相似文献   
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