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141.
142.

Background

Systemic lupus erythematosus (SLE) is a remarkably heterogeneous autoimmune disease. Despite tremendous efforts, our knowledge of serum protein patterns in severe SLE phenotypes is still limited. We investigated the serum protein pattern of SLE, with special emphasis on irreversible organ damage and active lupus nephritis (LN) as assessed by renal Systemic Lupus Erythematosus Disease Activity Index.

Methods

We used proximity extension immunoassay (PEA, Proseek Multiplex, Olink) to assess the serum levels of ninety-two inflammation-related proteins in Czech patients with SLE (n = 75) and age-matched healthy control subjects (n = 23). Subgroup analysis was carried out on the basis of organ damage (with/without, 42/33) and biopsy-proven LN (with/without, 27/48; active LN, n = 13; inactive LN, n = 14).

Results

Of thirty deregulated proteins between SLE and the healthy controls (P corr  < 0.05), the top upregulated proteins in SLE were sirtuin 2, interleukin 18 (IL18), and caspase 8 (P corr  < 0.0006). Of these, sirtuin 2 and caspase 8 had not yet been reported with SLE. Elevated levels of IL8, CCL2/MCP1, CCL11, and MMP10 (P corr  < 0.05) were detected in patients with organ damage for which the serum levels of CCL11 and MMP10 were particularly informative in organ damage prediction. Comparing patients based on LN, elevated levels of CSF1, sIL15RA, sCD40, sCX3CL1, caspase 8, sIL18R1, bNGF, and GDNF (P corr  < 0.05) were detected in active LN. Except GDNF, all LN-associated markers showed usefulness in prediction of active renal disease.

Conclusions

This highly sensitive PEA analysis identified the serum pattern of SLE, organ damage, and active LN, with many novel candidate proteins detected. Their exact role and suitability as biomarkers in SLE deserve further investigation.
  相似文献   
143.
A sterically constrained non-coded amino acid, 1-aminocyclopentane-1-carboxylic acid (Apc), was introduced in position 7 or 8 of the bradykinin (BK) B(2) receptor antagonist, [D-Arg(0), Hyp(3), Thi(5, 8), D-Phe(7)]BK, previously synthesized by Stewart's group. This modification is believed to reduce the flexibility of the peptides, thereby forcing the peptide backbone and side chains to adopt specific orientations. Apc substitution was combined with acylation of the N-terminus with 1-adamantaneacetic acid (Aaa). The activity of four new analogues was assayed in isolated rat uterus and in rat blood pressure tests. The results clearly demonstrated that the Apc residue inserted in position 7 led to a reduction of antagonistic properties in the rat uterus assay or even restored the agonism in the blood pressure test, whereas Apc at position 8 enhanced antagonistic potency in both the tests. In both cases, acylation of the N-terminus led to the enhancement of the antagonistic potency. On the basis of these findings, new potent and selective B(2) blockers might be designed.  相似文献   
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As duration of snow cover decreases owing to climate change, species undergoing seasonal colour moults can become colour mismatched with their background. The immediate adaptive solution to this mismatch is phenotypic plasticity, either in phenology of seasonal colour moults or in behaviours that reduce mismatch or its consequences. We observed nearly 200 snowshoe hares across a wide range of snow conditions and two study sites in Montana, USA, and found minimal plasticity in response to mismatch between coat colour and background. We found that moult phenology varied between study sites, likely due to differences in photoperiod and climate, but was largely fixed within study sites with only minimal plasticity to snow conditions during the spring white-to-brown moult. We also found no evidence that hares modify their behaviour in response to colour mismatch. Hiding and fleeing behaviours and resting spot preference of hares were more affected by variables related to season, site and concealment by vegetation, than by colour mismatch. We conclude that plasticity in moult phenology and behaviours in snowshoe hares is insufficient for adaptation to camouflage mismatch, suggesting that any future adaptation to climate change will require natural selection on moult phenology or behaviour.  相似文献   
146.
Cognitive behavior therapy (CBT) is by far the most examined type of psychological treatment for depression and is recommended in most treatment guide­lines. However, no recent meta-analysis has integrated the results of randomized trials examining its effects, and its efficacy in comparison with other psychotherapies, pharmacotherapies and combined treatment for depression remains uncertain. We searched PubMed, PsycINFO, Embase and the Cochrane Library to identify studies on CBT, and separated included trials into several subsets to conduct random-effects meta-analyses. We included 409 trials (518 comparisons) with 52,702 patients, thus conducting the largest meta-analysis ever of a specific type of psychotherapy for a mental disorder. The quality of the trials was found to have increased significantly over time (with increasing numbers of trials with low risk of bias, less waitlist control groups, and larger sample sizes). CBT had moderate to large effects compared to control conditions such as care as usual and waitlist (g=0.79; 95% CI: 0.70-0.89), which remained similar in sensitivity analyses and were still significant at 6-12 month follow-up. There was no reduction of the effect size of CBT according to the publication year (<2001 vs. 2001-2010 vs. >2011). CBT was significantly more effective than other psychotherapies, but the difference was small (g=0.06; 95% CI: 0-0.12) and became non-significant in most sensitivity analyses. The effects of CBT did not differ significantly from those of pharmacotherapies at the short term, but were significantly larger at 6-12 month follow-up (g=0.34; 95% CI: 0.09-0.58), although the number of trials was small, and the difference was not significant in all sensitivity analyses. Combined treatment was more effective than pharmacotherapies alone at the short (g=0.51; 95% CI: 0.19-0.84) and long term (g=0.32; 95% CI: 0.09-0.55), but it was not more effective than CBT alone at either time point. CBT was also effective as unguided self-help intervention (g=0.45; 95% CI: 0.31-0.60), in institutional settings (g=0.65; 95% CI: 0.21-1.08), and in children and adolescents (g=0.41; 95% CI: 0.25-0.57). We can conclude that the efficacy of CBT in depression is documented across different formats, ages, target groups, and settings. However, the superiority of CBT over other psychotherapies for depression does not emerge clearly from this meta-analysis. CBT appears to be as effective as pharmacotherapies at the short term, but more effective at the longer term.  相似文献   
147.
Insect herbivores have the potential to consume large amounts of plant tissue in tropical forests, but insectivorous vertebrates effectively control their abundances, indirectly increasing plant fitness accordingly. Despite several studies already sought understanding of the top-down effects on arthropod community structure and herbivory, such studies of trophic cascades in old tropics are underrepresented, and little attention was paid to top-down forces in various habitats. Therefore, we examine how flying insectivorous vertebrates (birds and bats) impact arthropods and, consequently, affect herbivore damage of leaves in forest habitats in Papua New Guinea. In a 3-month long predator exclosure experiment conducted at four study sites across varying elevation and successional stage, we found that vertebrate predators reduced arthropod density by ∼52%. In addition, vertebrate predators decreased the mean body size of arthropods by 26% in leaf chewers and 47% in non-herbivorous arthropods but had only a small effect on mesopredators and sap suckers. Overall, the exclusion of vertebrate predators resulted in a ~ 41% increase in leaf damage. Our results, across different types of tropical forests in Papua New Guinea, demonstrate that flying vertebrate insectivores have a crucial impact on plant biomass, create a selective pressure on larger and non-predatory prey individuals and they prey partition with mesopredators.  相似文献   
148.
Understanding how genetic variation is maintained in a metapopulation is a longstanding problem in evolutionary biology. Historical resurveys of polymorphisms have offered efficient insights about evolutionary mechanisms, but are often conducted on single, large populations, neglecting the more comprehensive view afforded by considering all populations in a metapopulation. Here, we resurveyed a metapopulation of spotted salamanders (Ambystoma maculatum) to understand the evolutionary drivers of frequency variation in an egg mass colour polymorphism. We found that this metapopulation was demographically, phenotypically and environmentally stable over the last three decades. However, further analysis revealed evidence for two modes of evolution in this metapopulation—genetic drift and balancing selection. Although we cannot identify the balancing mechanism from these data, our findings present a clear view of contemporary evolution in colour morph frequency and demonstrate the importance of metapopulation-scale studies for capturing a broad range of evolutionary dynamics.  相似文献   
149.
This article highlights some of the more notable persistent fungal diseases of our times. It draws attention to the emergence of new fungal pathotypes infecting food staple crops, due largely to modern agricultural practices, and to nascent fungal diseases decimating frog populations worldwide and killing hibernating bats in Northern USA. We invoke use of the basic disease triangle concept to highlight the “missing” data, with regards to pathogen and host biology and to the various environmental parameters which may dictate disease spread. Given these data “voids” we comment on the implementation of policy. We conclude with a series of recommendations for improved disease surveillance and reporting, the need for greater public awareness of these issues and a call for greater funding for fungal research. In so doing, we have exploited Magnaporthe oryzae and Batrachochytrium dendrobatidis as exemplar emerging infectious fungi. Our aim is to highlight the impact of emerging and emergent fungi on food security and, more broadly, ecosystem health.  相似文献   
150.
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