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1.
C. T. DARIMONT P. C. PAQUET T. E. REIMCHEN 《Biological journal of the Linnean Society. Linnean Society of London》2007,90(1):125-137
Interindividual variation in niche presents a potentially central object on which natural selection can act. This may have important evolutionary implications because habitat use governs a suite of selective forces encountered by foragers. In a free-living native black-tailed deer, Odocoileus hemionus , population from coastal British Columbia, we used stable isotope analysis to identify individual variation in foraging niche and investigated its relationship to fitness. Using an intragenerational comparison of surviving and nonsurviving O. hemionus over 2 years of predation by wolves, Canis lupus, we detected resource-specific fitness. Individuals with isotopic signatures that suggested they foraged primarily in cedar ( Thuja plicata )-dominated and low-elevation hemlock ( Tsuga heterophylla )-dominated forest stands were more likely to be killed by C. lupus . High-quality forage in T. plicata stands, as indexed by protein content, may be involved in maintaining this foraging phenotype. Moreover, nonsurvivors diverged more than survivors from median isotopic signatures, suggesting selection against foraging specialization. Stable isotope analysis provides a novel opportunity to integrate ecological and selective landscapes in order to identify underlying ecological mechanisms of selection and provide insight into the maintenance of variability. © 2007 The Linnean Society of London, Biological Journal of the Linnean Society , 2007, 90 , 125–137. 相似文献
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Somparn P Hirankarn N Leelahavanichkul A Khovidhunkit W Thongboonkerd V Avihingsanon Y 《Journal of Proteomics》2012,75(11):3240-3247
Although renal histopathology is the gold standard for the diagnosis and prognosis of lupus nephritis (LN), the invasiveness of renal biopsy warrants the discovery of novel non-invasive diagnostic and prognostic biomarkers. In the present study, urine samples from 10 LN patients (5 active and 5 inactive) were analyzed by two-dimensional gel electrophoresis (2-DE) to screen for potential biomarkers of active LN. Quantitative analysis and statistics revealed 16 protein spots whose levels significantly differed between groups. These proteins were successfully identified by electrospray ionization quadrupole time-of-flight tandem mass spectrometry (ESI-Q-TOF MS/MS). Among these potential candidates, differential levels of urinary Zn-α2-glycoprotein (ZA2G) and prostaglandin H(2)D-isomerase (PGDS) were further validated by enzyme-linked immunosorbent assay (ELISA) in another independent group of 78 subjects, including 30 active LN, 26 inactive LN, 14 non-LN glomerular diseases, and 8 healthy normal individuals. Whereas ZA2G levels were elevated in urine of patients with active LN and non-LN glomerular diseases, PGDS was elevated only in the urine of the active LN group. Urinary PGDS, not ZA2G, may serve as a biomarker for active LN and upon validation in larger studies, may become the non-invasive test to evaluate the disease activity in future management of LN. 相似文献
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Endotoxemia,vitamin D and premature biological ageing in Arab adults with different metabolic states
《Saudi Journal of Biological Sciences》2022,29(6):103276
There are limited studies on the association of endotoxin, a potent mediator of gut-derived inflammation and telomere length (TL). We investigated (1) the influence of adiposity on endotoxin and TL amongst Saudi adults according to type 2 diabetes mellitus (T2DM) status and (2) the influence vitamin D may have on TL attrition. Anthropometric data and fasting blood samples were taken from 775 Saudi adults visiting different primary care centers in Riyadh [387 T2DM and 388 non-T2DM]. TL, derived from peripheral blood mononuclear cells, was analyzed by Quantitative real-time polymerase chain reaction and circulating endotoxin levels by Limulus Amebocyte Lysate assay. Subjects were stratified based on obesity and T2DM status. A significant lower TL was observed in the non-obese T2DM group as compared with their non-obese, non-T2DM counterparts (p = 0.002). Significant inverse associations between TL, endotoxin and endotoxin activity were observed in the cohort with obesity. Regression analysis showed that endotoxin was a significant predictor for TL in all subjects and even after stratification according to subgroups; with variances perceived in circulating TL stronger among non-T2DM obese (10%; p = 0.003) than non-T2DM non-obese (12%; p = 0.007). Also, in the non-T2DM group, TL and HDL-cholesterol predicted 29% of the variances perceived in 25(OH)D (p < 0.001). Taken together these findings show that circulating endotoxin and 25(OH)D are associated with premature biological ageing influenced by adiposity and metabolic state; suggesting future intervention studies to manipulate gut microbiome and or vitamin D levels may offer ways to mitigate premature TL attrition. 相似文献
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Tsai‐Ching Hsu Chun‐Ching Chiu Yi‐Wen Wang Bor‐Show Tzang 《Journal of cellular and molecular medicine》2013,17(10):1308-1315
Attenuated antioxidant activities, irregular cytokines expressions and reduced regulatory T cells, are strongly associated with the pathogenesis of systemic lupus erythematosus (SLE). Despite the well‐established beneficial effects of cystamine on lupus‐prone mice, the extent to which cystamine contributes to antioxidant activity and the reduction of regulatory T cells has seldom been investigated. Therefore, this study elucidates how cystamine affects anti‐oxidant activities in NZB/W F1 mice by performing assays of Glutathione (GSH), 1,1‐diphenyl‐2‐ picryl‐hydrazyl (DPPH) and malondialdehyde thiobarbituric acid (MDA). In addition, investigations of the effects of cystamine on CD4+/CD25+ regulatory T cells and interleukin‐6 (IL6)/STAT‐3 signalling were performed with flow cytometry and immunoblots. Experimental results reveal more significantly reduced MDA and increased GSH and DPPH in NZB/W F1 mice receiving cystamine than in those mice receiving PBS. Meanwhile, CD4+/CD25+ regulatory T cells more significantly increase in NZB/W F1 mice receiving cystamine than in those mice receiving PBS, accompanied by significantly reduced IL‐6/phosphorylated STAT‐3 expression. The above findings suggest the beneficial effects of cystamine in terms of increasing antioxidant activities and CD4+/CD25+ regulatory T cells in lupus‐prone mice by suppressing IL‐6/STAT3 signalling. 相似文献
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《Cell》2022,185(18):3375-3389.e21
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DITTE HOLM ANDERSEN ELENA FABBRI ALBERTO SANTINI SANDRINE PAGET EDOUARD CADIEU FRANCIS GALIBERT CATHERINE ANDR ETTORE RANDI 《Molecular ecology resources》2006,6(4):1184-1187
We characterized 59 canine single nucleotide polymorphisms (SNPs) in the endangered Italian wolf (Canis lupus) population, which were discovered by resequencing sequence‐tagged‐site (STS) DNA sequences that are known to contain SNPs in domestic dogs. Dog SNPs were usually found also in wolves. Additional SNPs unique in dogs or wolves were discovered, which is important for detecting hybrids between dogs and wolves. We developed new primer sets and analysed 15 SNPs by Pyrosequencing. The characterized SNPs will provide an important addition to the genetic markers that are currently available for studying wild populations of canids. 相似文献
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Malory Randon Christophe Bonenfant Jacques Michallet Thierry Chevrier Carole Toïgo Jean-Michel Gaillard Marion Valeix 《Population Ecology》2020,62(2):244-257
In a context of changing carnivore populations worldwide, it is crucial to understand the consequences of these changes for prey populations. The recolonization by wolves of the French Vercors mountain range and the long-term monitoring (2001–2017) of roe deer in this area provided a unique opportunity to assess the effects of wolves on this prey. Roe deer was the main prey of wolves in the west Vercors mountain range during this recolonization. We compared roe deer abundance and fawn body mass in two contrasted areas of a wolf pack territory: a central area (core of the territory characterized by an intense use by wolves) and a peripheral area (used more occasionally). Roe deer population growth rates were lower in the central area between 2001 and 2006, resulting in a decline in roe deer abundance. Roe deer abundance substantially dropped in the two study areas after an extremely severe winter but the abundance of roe deer in the central area facing with wolves was slower to recover and remained at lower abundance levels for 6 years. Fawn body mass was consistently lower in the central area, varied similarly as roe deer abundance, and was not influenced by weather conditions or red deer population abundance. Altogether, the effects of wolves on roe deer in the central area occurred during a 10-year period following the establishment of wolves, through the interplay between wolf predation (before wolves started preying on red deer), harsh winter conditions and possibly naivety of prey to this recolonizing predator. 相似文献
10.
Marilisa Villano Annalisa Borghini Mirko Manetti Erica Gabbrielli Antonella Rossi Piersante Sestini Anna Franca Milia Francesca Nacci Serena Guiducci Marco Matucci-Cerinic Lidia Ibba-Manneschi Elisabetta Weber 《Arthritis research & therapy》2013,15(4):R90