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1.
A number of lipid products are formed during the desaturation of stearyl CoA by hen liver microsomes. This article presents an analysis of the products formed when [1-14C] stearyl CoA is incubated with hen liver microsomes for various time periods. [1-14C] Oleyl CoA was the first radioactive unsaturated product formed. Synthesis of phospholipids containing [1-14C] oleic acid occurs only after the desaturase activity has begun to decline. The specific radioactivity of [1-14C] oleyl CoA was similar to the specific radioactivity of [1-14C] stearyl CoA at all time periods tested. The specific radioactivities of [1-14C] oleic acid and phospholipids containing [1-14C] oleic acid were much lower than that of the [1-14C] stearyl CoA.  相似文献   
2.
The action of the tumor promoter, phorbol 12,13-dibutyrate (PDBu), on rabbit peritoneal and human neutrophils is associated with stimulation of14C-arachidonic acid incorporation into phospholipids within 1–2 min. Stimulated14C-arachidonate incorporation was relatively selective for phosphatidylinositol (PI) in rabbit neutrophils. In contrast, the secretory response of human neutrophils to PDBu coincided with stimulated label incorporation into phosphatidylserine (PS), phosphatidylcholine (PC), phosphatidylethanolamine (PE), phosphatidic acid (PA) and PI. Significant increases in label incorporation were observed with PDBu concentrations as low as 2 nM, and the dose response of stimulated label incorporation paralleled that of evoked lysozyme secretion. A parallel, but partial, inhibition of PDBu-stimulated PI labeling and enzyme release was observed after exposing rabbit neutrophils to calcium-deprived medium, whereas calcium deprivation failed to significantly depress either of these stimulant actions of PDBu in human neutrophils. Further, in rabbit neutrophils PDBu elicited an increase in cell associated45Ca. However, PDBu was unable to promote the incorporation of32P orthophosphate into PI or enhance phospholipase A2 activity in broken cells. These findings suggest that one expression of the interaction between phorbol esters and their receptors on neutrophils involves the turnover of arachidonic acid in phospholipids. This stimulated turnover of arachidonate may be a critical step in the cascade of events associated with neutrophil activation.  相似文献   
3.
Caroline Cannizzo 《Polymer》2005,46(4):1269-1276
Translucent boronic acid-carrying nanolatexes are prepared by copolymerisation of vinylbenzyl chloride in microemulsion followed by post functionalisation with 3-aminophenylboronic acid. The diol binding capacity and selectivity of the phenylboronic acid remain unchanged after anchoring to polymer nanoparticles (16 nm diameter, 0.22 mmol/g). The binding of a catechol dye, Alizarin Red S (ARS), to the boronic acid-carrying nanoparticles affords a colored, stable, nanolatex which is used for the selective visual detection of fructose in a competitive assay. The binding of fructose at pH 8.2 is readily evidenced by a color change and monitored by UV/Vis spectroscopy. The nanosensor can be regenerated in acidic medium. The entrapment of the nanolatex in a dialysis cell provides a re-usable support for binding and optical detection.  相似文献   
4.
Witnessing in merging biological, social and algorithmic realities is crucial to trust, as modelled in the YUTPA framework. Being witness and bearing witness is fundamental to human interaction. System participation in human communities of practice challenges the notion of witnessing and therefore the ability to build trust. Nevertheless, through trial and error, people in a variety of practices have found ways to establish the presence and develop trust in merging realities. This paper presents the results of 20 in-depth interviews with professionals from a variety of disciplines and nations. The conclusion of cumulative analysis is that systems do not witness themselves, but their output deeply affects the mental maps that human beings make of each other, the world around them and their own self. Essential qualities human beings seek when being involved with other beings are defined by granularity and reciprocity in the design of time (duration of engagement, synchronizing performance, integrating rhythms and moments to signify), place (body sense, material interaction, emotional space and situated agency), relation (shared meaning, engagement, reputation and use) and action (tuning, reciprocity, negotiation and quality of deeds). By designing granular interaction in 4 dimensions, reciprocity in witnessing obtains significance and the basis for establishing trust in a variety of presences emerges while human agency acquires potential.  相似文献   
5.
Human T cell leukemia virus type 1 (HTLV-1) was identified as the first pathogenic human retrovirus and is estimated to infect 5 to 10 million individuals worldwide. Unlike other retroviruses, there is no effective therapy to prevent the onset of the most alarming diseases caused by HTLV-1, and the more severe cases manifest as the malignant phenotype of adult T cell leukemia (ATL). MicroRNA (miRNA) dysfunction is a common feature of leukemogenesis, and it is no different in ATL cases. Therefore, we sought to analyze studies that reported deregulated miRNA expression in HTLV-1 infected cells and patients’ samples to understand how this deregulation could induce malignancy. Through in silico analysis, we identified 12 miRNAs that stood out in the prediction of targets, and we performed functional annotation of the genes linked to these 12 miRNAs that appeared to have a major biological interaction. A total of 90 genes were enriched in 14 KEGG pathways with significant values, including TP53, WNT, MAPK, TGF-β, and Ras signaling pathways. These miRNAs and gene interactions are discussed in further detail for elucidation of how they may act as probable drivers for ATL onset, and while our data provide solid starting points for comprehension of miRNAs’ roles in HTLV-1 infection, continuous effort in oncologic research is still needed to improve our understanding of HTLV-1 induced leukemia.  相似文献   
6.
The standard modeling framework in functional magnetic resonance imaging (fMRI) is predicated on assumptions of linearity, time invariance and stationarity. These assumptions are rarely checked because doing so requires specialized software, although failure to do so can lead to bias and mistaken inference. Identifying model violations is an essential but largely neglected step in standard fMRI data analysis. Using Lagrange multiplier testing methods we have developed simple and efficient procedures for detecting model violations such as nonlinearity, nonstationarity and validity of the common double gamma specification for hemodynamic response. These procedures are computationally cheap and can easily be added to a conventional analysis. The test statistic is calculated at each voxel and displayed as a spatial anomaly map which shows regions where a model is violated. The methodology is illustrated with a large number of real data examples.  相似文献   
7.
Photonic Network Communications - Forthcoming wireless systems are developed to support greater data rate and extra coverage area. This can be achieved with the help of multiple input multiple...  相似文献   
8.
The treatment of oxidized Cu surfaces using an alkanethiol as a reducing agent has been investigated. Exposure to a dilute solution of 1-decanethiol resulted in the complete removal and/or conversion of CuO and subsequent formation of a passivating thiolate film, a so-called self-assembled monolayer (SAM), on the underlying Cu/Cu2O surface as evidenced by x-ray photoelectron spectroscopy (XPS) analysis. Morphological changes, monitored by scanning electron microscopy (SEM) and atomic force microscopy (AFM), revealed transformation of the rough, porous CuO layer into a comparatively smooth Cu/Cu2O surface. Experiments performed on integrated circuit back-end-of-line (BEOL) die structures, comprising Cu/SiO2 bond pads used as substrates for Cu wire bonding, demonstrate the potential application of a thiol-based in-situ cleaning-passivation procedure in microelectronics.  相似文献   
9.
This research describes the detailed analysis and design of the compact complex-free structural metamaterial quad band radiating element applicable for Bluetooth, WiMAX, WLAN, and fixed-satellite service. The radiating element designed is composed of an inner angle-rotated circular Split Ring Resonator (SRR) placed within the outer square-shaped SRR interlinked by a strip to design the multiband operational characteristics and is fed by a coplanar waveguide. Suggested radiating element is imprinted over the FR4 substrate material with the electrical dimension of 28 × 31.26 × 0.8 mm3. The initial outer-closed square ring offers dual-band operation by resonating at 2.8 and 8.5 GHz frequencies, and the incorporation of a circular SRR offers quad-band operation. The unique negative permeability feature of the proposed Square and Circular Split Ring Resonator (SCSRR) structure is extracted, and its band characteristics are analyzed. Results obtained from the simulated radiating element are validated with the fabricated antenna. The measured E plane pattern resembles a numeric eight shape, and the H plane pattern is omnidirectional. Suggested SCSRR antenna offers a gain of above 3.2 dBi in all the operating bands.  相似文献   
10.
Subunit vaccines use delivery platforms to present minimal antigenic components for immunization. The benefits of such systems include multivalency, self‐adjuvanting properties, and more specific immune responses. Previously, the design, synthesis, and characterization of self‐assembling peptide cages (SAGEs) have been reported. In these, de novo peptides are combined to make hubs that assemble into nanoparticles when mixed in aqueous solution. Here it is shown that SAGEs are nontoxic particles with potential as accessible synthetic peptide scaffolds for the delivery of immunogenic components. To this end, SAGEs functionalized with the model antigenic peptides tetanus toxoid632‐651 and ovalbumin323‐339 drive antigen‐specific responses both in vitro and in vivo, eliciting both CD4+ T cell and B cell responses. Additionally, SAGEs functionalized with the antigenic peptide hemagglutinin518‐526 from the influenza virus are also able to drive a CD8+ T cell response in vivo. This work demonstrates the potential of SAGEs to act as a modular scaffold for antigen delivery, capable of inducing and boosting specific and tailored immune responses.  相似文献   
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