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81.
Inflammation induced by wound healing or infection activates local vascular endothelial cells to mediate leukocyte rolling, adhesion, and extravasation by up-regulation of leukocyte adhesion molecules such as E-selectin and P-selectin. Obesity-associated adipose tissue inflammation has been suggested to cause insulin resistance, but weight loss and lipolysis also promote adipose tissue immune responses. While leukocyte-endothelial interactions are required for obesity-induced inflammation of adipose tissue, it is not known whether lipolysis-induced inflammation requires activation of endothelial cells. Here, we show that β3-adrenergic receptor stimulation by CL 316,243 promotes adipose tissue neutrophil infiltration in wild type and P-selectin-null mice but not in E-selectin-null mice. Increased expression of adipose tissue cytokines IL-1β, CCL2, and TNF-α in response to CL 316,243 administration is also dependent upon E-selectin but not P-selectin. In contrast, fasting increases adipose-resident macrophages but not neutrophils, and does not activate adipose-resident endothelium. Thus, two models of lipolysis-induced inflammation induce distinct immune cell populations within adipose tissue and exhibit distinct dependences on endothelial activation. Importantly, our results indicate that β3-adrenergic stimulation acts through up-regulation of E-selectin in adipose tissue endothelial cells to induce neutrophil infiltration.  相似文献   
82.
In Parus major, P. caeruleus, and P. ater the genetic variation of 16 isozyme loci was determined. The focus was on esterases that show high phenotypic variation in natural populations of these species. The degree of heterozygosity of the "non-esterase" loci was 0.029 +/- 0.008 (P. major); 0.023 +/- 0.012 (P. caeruleus), and 0.034 +/- 0.034 (P. ater). Including the esterase loci with up to six alleles per locus the overall degree of heterozygosity increased to 0.130 +/- 0.056 (P. major); 0.143 +/- 0.067 (P. caeruleus), and 0.194 +/- 0.090 (P. ater). We explain the high level of variability of esterases by gene amplification and subsequent selection for high allelic heterogeneity. Substrate specificity of loci is assumed to allow for multiple resistance against various toxic components. Large allelic valiation of esterases, therefore, increases the fitness of Parus species and allows for utilizing new food resources.  相似文献   
83.

Background

Many fish species experience long periods of fasting in nature often associated with seasonal reductions in water temperature and prey availability or spawning migrations. During periods of nutrient restriction, changes in metabolism occur to provide cellular energy via catabolic processes. Muscle is particularly affected by prolonged fasting as myofibrillar proteins act as a major energy source. To investigate the mechanisms of metabolic reorganisation with fasting and refeeding in a saltwater stage of Atlantic salmon (Salmo salar L.) we analysed the expression of genes involved in myogenesis, growth signalling, lipid biosynthesis and myofibrillar protein degradation and synthesis pathways using qPCR.

Results

Hierarchical clustering of gene expression data revealed three clusters. The first cluster comprised genes involved in lipid metabolism and triacylglycerol synthesis (ALDOB, DGAT1 and LPL) which had peak expression 3-14d after refeeding. The second cluster comprised ADIPOQ, MLC2, IGF-I and TALDO1, with peak expression 14-32d after refeeding. Cluster III contained genes strongly down regulated as an initial response to feeding and included the ubiquitin ligases MuRF1 and MAFbx, myogenic regulatory factors and some metabolic genes.

Conclusion

Early responses to refeeding in fasted salmon included the synthesis of triacylglycerols and activation of the adipogenic differentiation program. Inhibition of MuRF1 and MAFbx respectively may result in decreased degradation and concomitant increased production of myofibrillar proteins. Both of these processes preceded any increase in expression of myogenic regulatory factors and IGF-I. These responses could be a necessary strategy for an animal adapted to long periods of food deprivation whereby energy reserves are replenished prior to the resumption of myogenesis.  相似文献   
84.

Background

Compulsory admission to psychiatric hospitals may be distressing, disruptive to patients and families, and associated with considerable cost to the health service. Improved patient experience and cost reductions could be realised by providing cost-effective crisis planning services.

Methods

Economic evaluation within a multi-centre randomised controlled trial comparing Joint Crisis Plans (JCP) plus treatment as usual (TAU) to TAU alone for patients aged over 16, with at least one psychiatric hospital admission in the previous two years and on the Enhanced Care Programme Approach register. JCPs, containing the patient''s treatment preferences for any future psychiatric emergency, are a form of crisis intervention that aim to mitigate the negative consequences of relapse, including hospital admission and use of coercion. Data were collected at baseline and 18-months after randomisation. The primary outcome was admission to hospital under the Mental Health Act. The economic evaluation took a service perspective (health, social care and criminal justice services) and a societal perspective (additionally including criminal activity and productivity losses).

Findings

The addition of JCPs to TAU had no significant effect on compulsory admissions or total societal cost per participant over 18-months follow-up. From the service cost perspective, however, evidence suggests a higher probability (80%) of JCPs being the more cost-effective option. Exploration by ethnic group highlights distinct patterns of costs and effects. Whilst the evidence does not support the cost-effectiveness of JCPs for White or Asian ethnic groups, there is at least a 90% probability of the JCP intervention being the more cost-effective option in the Black ethnic group.

Interpretation

The results by ethnic group are sufficiently striking to warrant further investigation into the potential for patient gain from JCPs among black patient groups.

Trial Registration

Current Controlled Trials ISRCTN11501328  相似文献   
85.

Background  

The secretin family is a pleotropic group of brain-gut peptides with affinity for class 2 G-protein coupled receptors (secretin family GPCRs) proposed to have emerged early in the metazoan radiation via gene or genome duplications. In human, 10 members exist and sequence and functional homologues and ligand-receptor pairs have been characterised in representatives of most vertebrate classes. Secretin-like family GPCR homologues have also been isolated in non-vertebrate genomes however their corresponding ligands have not been convincingly identified and their evolution remains enigmatic.  相似文献   
86.
87.

Background  

Citrus canker is a disease caused by the phytopathogens Xanthomonas citri subsp. citri, Xanthomonas fuscans subsp. aurantifolli and Xanthomonas alfalfae subsp. citrumelonis. The first of the three species, which causes citrus bacterial canker type A, is the most widely spread and severe, attacking all citrus species. In Brazil, this species is the most important, being found in practically all areas where citrus canker has been detected. Like most phytobacterioses, there is no efficient way to control citrus canker. Considering the importance of the disease worldwide, investigation is needed to accurately detect which genes are related to the pathogen-host adaptation process and which are associated with pathogenesis.  相似文献   
88.
Pulmonary surfactant, a thin lipid/protein film lining mammalian lungs, functions in vivo to reduce the work of breathing and to prevent alveolar collapse. Analogues of two hydrophobic surfactant proteins, SP-B and SP-C, have been incorporated into therapeutic agents for respiratory distress syndrome, a pathological condition resulting from deficiency in surfactant. To facilitate rational design of therapeutic agents, a molecular level understanding of lipid interaction with surfactant proteins or their analogues in aqueous monolayer films is necessary. The current work uses infrared reflection-absorption spectroscopy (IRRAS) to determine peptide conformation and the effects of S-palmitoylation on the lipid interactions of a synthetic 13 residue N-terminal peptide [SP-C13(palm)(2)] of SP-C, in mixtures with 1,2-dipalmitoylphosphatidylcholine (DPPC) or 1,2-dipalmitoylphosphatidylglycerol (DPPG). Two Amide I' features, at approximately 1655 and approximately 1639 cm(-1) in the peptide IRRAS spectra, are assigned to alpha-helical peptide bonds in hydrophobic and aqueous environments, respectively. In binary DPPC/SP-C13(palm)(2) films, the proportion of hydrated/hydrophobic helix increases reversibly with surface pressure (pi), suggestive of the peptide being squeezed out from hydrophobic regions of the monolayer. No such effect was observed for DPPG/peptide monolayers, indicative of stronger, probably electrostatic, interactions. Depalmitoylation produced a weakened interaction with either phospholipid as deduced from IRRAS spectra and from pi-area isotherms. S-Palmitoylation may modulate peptide hydration and conformation in the N-terminal region of SP-C and may thus permit the peptide to remain in the film at the high surface pressures present during lung compression. The unique capability of IRRAS to detect the surface pressure dependence of protein or peptide structure/interactions in a physiologically relevant model for surfactant is clearly demonstrated.  相似文献   
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