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1.
Microarray-driven gene-expression profiles are generally produced and analyzed for a single specific experimental model. We have assessed an analytical approach that simultaneously evaluates multi-species experimental models within a particular biological condition using orthologous genes as linkers for the various Affymetrix microarray platforms on multi-species models of ventilator-associated lung injury. The results suggest that this approach may be a useful tool in the evaluation of biological processes of interest and selection of process-related candidate genes.  相似文献   
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Background

Chronic obstructive pulmonary disease (COPD) is characterised by pulmonary and systemic inflammation which flare-up during episodes of acute exacerbation (AECOPD). Given the role of Toll-like receptors (TLRs) in the induction of inflammatory responses we investigated the involvement of TLRs in COPD pathogenesis.

Methods

The expression of TLR-2, TLR-4 and CD14 in monocytes was analyzed by flow cytometry. To study the functional responses of these receptors, monocytes were stimulated with peptidoglycan or lipopolysaccharide and the amounts of TNFα and IL-6 secreted were determined by ELISA.

Results

We found that the expression of TLR-2 was up-regulated in peripheral blood monocytes from COPD patients, either clinically stable or during AECOPD, as compared to never smokers or smokers with normal lung function. Upon stimulation with TLR-2 ligand monocytes from COPD patients secreted increased amounts of cytokines than similarly stimulated monocytes from never smokers and smokers. In contrast, the expressions of TLR-4 and CD14 were not significantly different between groups, and the response to lipopolysaccharide (a TLR-4 ligand) stimulation was not significantly different either. At discharge from hospital TLR-2 expression was down-regulated in peripheral blood monocytes from AECOPD patients. This could be due to the treatment with systemic steroids because, in vitro, steroids down-regulated TLR-2 expression in a dose-dependent manner. Finally, we demonstrated that IL-6, whose plasma levels are elevated in patients, up-regulated in vitro TLR-2 expression in monocytes from never smokers.

Conclusion

Our results reveal abnormalities in TLRs expression in COPD patients and highlight its potential relationship with systemic inflammation in these patients.
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The composition of the fatty acids of astaxanthin esters and the distribution of astaxanthin optical RS isomers in the esterified and unesterified astaxanthin fractions extracted from the meal of the pelagic red crab langostilla (Pleuroncodes planipes; Decapoda, Anomura) were determined. Astaxanthin diesters comprised approximately 70%, monoesterified astaxanthin approximately 12%, and unesterified astaxanthin approximately 10% of total carotenoids, respectively. Unidentified carotenes and minor yellow xanthophylls represented approximately 8% of the total carotenoids. Three astaxanthin diester fractions (ratio 5:4:1) and one monoester fraction were clearly distinguished by thin-layer chromatography, and fatty acid moieties were determined in all of them. Saturated fatty acids accumulated in astaxanthin diesters, but were reduced in the monoester fraction when compared to langostilla crude oil extract (CE). Astaxanthin diesters, but not monoesters were enriched in C16:0 and C18:1n-9, when compared to the CE. Astaxanthin monoesters were rich in polyunsaturated fatty acids (approximately 70% of total fatty acids), in particular C20:5n-3 and C22:6n-3. Acylation of astaxanthin in langostilla seems to be selective rather than specific. The three diesterified astaxanthin fractions of langostilla had a ratio of approximately 3:1:3 between the (3R,3'R)-, (3R,3'S)-, and (3S,3'S)-astaxanthin isomers, whereas in the monoesterified and unesterified fractions the ratio was approximately 4:1:4. The astaxanthin optical RS isomer composition indicates that langostilla is unable to racemize astaxanthin.  相似文献   
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Accumulation of lipids and carotenoids, including 4'-hydroxyechinenone (4'-hydroxy-beta,beta-carotene-4-one), growth and condition factor were investigated in Atlantic salmon (Salmo salar) transferred to seawater as 0+ and 1+ smolts. Salmon were fed a diet with 30 mg/kg astaxanthin (3,3'-dihydroxy-beta,beta-carotene-4,4'-dione) and 30 mg/kg canthaxanthin (beta,beta-carotene-4,4'-dione) for 35 weeks. The 0+ smolt contained more carotenoids than the 1+ smolt when mass differences were corrected for (P<0.0001), a difference also reflected by the tristimulus colour measurements (C1E a*- and b*-values). Astaxanthin and canthaxanthin comprised more than 93% of the total carotenoids, but small differences were observed in carotenoid composition. The condition factor was significantly higher in 0+ than 1+ smolts after correction for mass differences (P<0.01). There was a high correlation between ln-transformed muscle lipid (%) and ln-transformed body mass for 0+(R2=0.94) and 1+smolts (R2=0.97). The canthaxanthin metabolite 4'-hydroxyechinenone was isolated from muscle of Atlantic salmon fed a diet supplemented with canthaxanthin. It was characterised and identified by its absorption maximum (lambda(max)=458 nm in n-hexane), mass spectrometry (M+=566) and co-chromatography with authentic standard obtained by NaBH4-reduction of canthaxanthin on thin-layer chromatography and HPLC. HPLC of the camphanates of 4'-hydroxyechinenone revealed a stereoselective transformation in favour of the (4'S)-isomer, the (4'S) and (4'R)-isomers comprising approximately 81 and 19% of the total 4'-hydroxyechinenone, respectively. The percentage of 4'-hydroxyechineone of total carotenoids ranged from 1.3 to 3.1% and declined with fish size (P<0.001). We conclude that effects of time of seawater transfer of Atlantic salmon smolts have significant effect on carotenoid accumulation and other quality traits. The detailed biochemical and physiological basis for these differences require further elucidation.  相似文献   
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Appearance, pharmacokinetics and distribution of astaxanthin all-E-, 9Z- and 13Z-geometrical and (3R,3'R)-, (3R,3'S)- and (3S,3'S)-optical isomers in plasma fractions were studied in three middle-aged male volunteers (41-50 years) after ingestion of a single meal containing first a 10-mg dose equivalent of astaxanthin from astaxanthin diesters, followed by a dose of 100 mg astaxanthin equivalents after 4 weeks. Direct resolution of geometrical isomers and optical isomers of astaxanthin dicamphanates by HPLC after saponification showed that the astaxanthin consisted of 95.2% all-E-, 1.2% 9Z- and 3.6% 13Z-astaxanthin, of (3R,3'R)-, (3R,3'S; meso)- and (3S,3'S)-astaxanthin in a 31:49:20 ratio. The plasma astaxanthin concentration-time curves were measured during 76 h. Astaxanthin esters were not detected in plasma. Maximum levels of astaxanthin (C(max)=0.28+/-0.1 mg/l) were reached 11.5 h after administration and the plasma astaxanthin elimination half-life was 52+/-40 h. The C(max) at the low dose was 0.08 mg/l and showed that, the dose response was non-linear. The (3R,3'R)-astaxanthin optical isomer accumulated selectively in plasma compared to the (3R,3'S)- and (3S,3'S)-isomers, and comprised 54% of total astaxanthin in the blood and only 31% of total astaxanthin in the administered dose. The astaxanthin Z-isomers were absorbed selectively into plasma and comprised approximately 32% of total astaxanthin 6-7.5 h postprandially. The proportion of all-E-astaxanthin was significantly higher in the very low density lipoproteins and chylomicrons (VLDL/CM) plasma lipoprotein fraction than in the high density lipoproteins (HDL) and low denisty lipoproteins (LDL) fractions (P<0.05). The results indicate that a selective process increase the relative proportion of astaxanthin Z-isomers compared to the all-E-astaxanthin before uptake in blood and that the astaxanthin esters are hydrolyzed selectively during absorption.  相似文献   
7.
Recreational big game hunters make a significant contribution to conservation through kills of deer, pigs, chamois and tahr. New opportunities for managing recreational hunting through the proposed Game Animal Council underscore the need to understand the implications of potential changes in recreational hunting participation and harvests. Based on a survey of hunters' recall over a year, hunters averaged 15.63 (SEM = 0.58) big game hunts per year, spending 30.53 (SEM = 0.85) days hunting and killing 8.92 (SEM = 0.69) big game animals. Hunters commonly targeted several species on a single hunt, with highly skewed distributions for hunter effort and kills. Mean monthly expenditure on big game hunting items was $296.78 (SEM = $8.95). Results demonstrate that big game hunting is a significant activity in New Zealand, but this varies considerably among hunters with a small number responsible for the vast majority of kills. These are important considerations for future big game hunting management.  相似文献   
8.
Neuropathic pain may arise following peripheral nerve injury though the molecular mechanisms associated with this are unclear. We used proteomic profiling to examine changes in protein expression associated with the formation of hyper-excitable neuromas derived from rodent saphenous nerves. A two-dimensional difference gel electrophoresis (2D-DIGE) profiling strategy was employed to examine protein expression changes between developing neuromas and normal nerves in whole tissue lysates. We found around 200 proteins which displayed a >1.75-fold change in expression between neuroma and normal nerve and identified 55 of these proteins using mass spectrometry. We also used immunoblotting to examine the expression of low-abundance ion channels Nav1.3, Nav1.8 and calcium channel α2δ-1 subunit in this model, since they have previously been implicated in neuronal hyperexcitability associated with neuropathic pain. Finally, S35methionine in vitro labelling of neuroma and control samples was used to demonstrate local protein synthesis of neuron-specific genes. A number of cytoskeletal proteins, enzymes and proteins associated with oxidative stress were up-regulated in neuromas, whilst overall levels of voltage-gated ion channel proteins were unaffected. We conclude that altered mRNA levels reported in the somata of damaged DRG neurons do not necessarily reflect levels of altered proteins in hyper-excitable damaged nerve endings. An altered repertoire of protein expression, local protein synthesis and topological re-arrangements of ion channels may all play important roles in neuroma hyper-excitability.  相似文献   
9.
Microscopic examination of living, protoperithecium-bearing colonies of a, A, and a + A that have been challenged by macroconidia from the same three colony types has shown that active trichogynes, i.e., those that grow to and fuse with a conidium, are to be found only in the first two types. Thus, in the a colony the trichogynes respond to conidia from the A and a + A colonies while in the A colony they respond to conidia from a and a + A colonies. In contrast to this ability of conidia from a + A colonies to function as fertilizing elements, the trichogynes of these colonies, if indeed they are formed at all, do not so respond. This nonresponse in a + A colonies may be due to the perithecia that are developing at the time of the challenge. Evidence for this conclusion comes from unimating type colonies in which the two halves of each colony were challenged at different times, 48 h apart. Trichogynes and perithecia developed in the first half; neither developed in the second. This inhibition of trichogyne development and response in the presence of developing perithecia may be only one manifestation of a more general inhibitory action by these structures.  相似文献   
10.
Exposure to cocaine generates silent synapses in the nucleus accumbens (NAc), whose eventual unsilencing/maturation by recruitment of calcium‐permeable AMPA‐type glutamate receptors (CP‐AMPARs) after drug withdrawal results in profound remodeling of NAc neuro‐circuits. Silent synapse‐based NAc remodeling was shown to be critical for several drug‐induced behaviors, but its role in acquisition and retention of the association between drug rewarding effects and drug‐associated contexts has remained unclear. Here, we find that the postsynaptic proteins PSD‐93, PSD‐95, and SAP102 differentially regulate excitatory synapse properties in the NAc. Mice deficient for either of these scaffold proteins exhibit distinct maturation patterns of silent synapses and thus provided instructive animal models to examine the role of NAc silent synapse maturation in cocaine‐conditioned place preference (CPP). Wild‐type and knockout mice alike all acquired cocaine‐CPP and exhibited increased levels of silent synapses after drug‐context conditioning. However, the mice differed in CPP retention and CP‐AMPAR incorporation. Collectively, our results indicate that CP‐AMPAR‐mediated maturation of silent synapses in the NAc is a signature of drug–context association, but this maturation is not required for establishing or retaining cocaine‐CPP.  相似文献   
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