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101.
Brais RJ Davies SE O'Donovan M Simpson BW Cook N Darbonne WC Chilcott S Lolkema MP Neesse A Lockley M Corrie PG Jodrell DI Praseedom RK Huguet EL Jah A Jamieson NV de Sauvage FJ Tuveson DA Carroll NR 《Pancreatology : official journal of the International Association of Pancreatology (IAP) ... [et al.]》2012,12(1):8-15
102.
103.
Numerous behavioral studies have shown that animals use olfactory cues as inbreeding avoidance or kin avoidance mechanisms, implying that scent is unique to families. However, few studies have analyzed the chemical profile of a scent and ascertained the messages that are conveyed in scent secretions. Owl monkeys (Aotus nancymaae) are socially monogamous primates that utilize scent when interacting with foreign conspecifics. This suggests there is a difference in the chemical composition of scent marks. We chemically analyzed sub-caudal gland samples from three families of captive owl monkeys (Aotus nancymaae). Samples were analyzed by capillary GC-MS and relative retention time and fragment pattern was compared with known standards. Gland samples were high in large plant-based shikikate metabolites and fatty ketones; alcohols, acids, and acetates were virtually absent. Gender, age, and family could be reliably classified using discriminant analysis (92.9, 100, and 100%, respectively). Female scent profiles were greater in concentration of aromatic plant metabolites, possibly the result of a different diet or physiological differences in female metabolism as compared to male. Offspring of adult age still living in their natal group showed a less complex chemical profile than their parents. Finally, each family had its own unique and complex chemical profile. The presence of family scent may play a role in mediating social interactions. 相似文献
104.
Endothelial dysfunction has been associated with the development of atherosclerosis and cardiovascular diseases. Adult endothelial progenitor cells(EPCs) are derived from hematopoietic stem cells and are capable of forming new blood vessels through a process of vas-culogenesis. There are studies which report correlations between circulating EPCs and cardiovascular risk fac-tors. There are also studies on how pharmacotherapies may influence levels of circulating EPCs. In this review, we discuss the potential role of endothelial progenitor cells as both diagnostic and prognostic biomarkers. In addition, we look at the interaction between cardio-vascular pharmacotherapies and endothelial progenitor cells. We also discuss how EPCs can be used directly and indirectly as a therapeutic agent. Finally, we evalu-ate the challenges facing EPC research and how these may be overcome. 相似文献
105.
Miller CL Kinsella JM Garner MM Evans S Gullett PA Schmidt RE 《The Journal of parasitology》2006,92(2):406-408
Parastrongylus (=Angiostrongylus) costaricensis was first reported in the United States from cotton rats, Sigmodon hispidus, in Texas in 1979. Here, we report the findings of P. costaricensis in a siamang (Hylobates syndactylus) from the Miami MetroZoo, in 2 Ma's night monkeys (Aotus nancymaae) from the DuMond Conservancy located at Monkey Jungle in Miami, in 4 raccoons (Procyon lotor) trapped near the MetroZoo, and in an opossum (Didelphis virginiana) trapped at the MetroZoo. These records are the first records of P. costaricensis from all 4 species of hosts. All of the primates were zoo-born, and the raccoons and opossum were native, indicating that this parasite is now endemic at these 2 sites. 相似文献
106.
Carr CA Stuckey DJ Tatton L Tyler DJ Hale SJ Sweeney D Schneider JE Martin-Rendon E Radda GK Harding SE Watt SM Clarke K 《American journal of physiology. Heart and circulatory physiology》2008,295(2):H533-H542
Basic and clinical studies have shown that bone marrow cell therapy can improve cardiac function following infarction. In experimental animals, reported stem cell-mediated changes range from no measurable improvement to the complete restoration of function. In the clinic, however, the average improvement in left ventricular ejection fraction is around 2% to 3%. A possible explanation for the discrepancy between basic and clinical results is that few basic studies have used the magnetic resonance (MR) imaging (MRI) methods that were used in clinical trials for measuring cardiac function. Consequently, we employed cine-MR to determine the effect of bone marrow stromal cells (BMSCs) on cardiac function in rats. Cultured rat BMSCs were characterized using flow cytometry and labeled with iron oxide particles and a fluorescent marker to allow in vivo cell tracking and ex vivo cell identification, respectively. Neither label affected in vitro cell proliferation or differentiation. Rat hearts were infarcted, and BMSCs or control media were injected into the infarct periphery (n = 34) or infused systemically (n = 30). MRI was used to measure cardiac morphology and function and to determine cell distribution for 10 wk after infarction and cell therapy. In vivo MRI, histology, and cell reisolation confirmed successful BMSC delivery and retention within the myocardium throughout the experiment. However, no significant improvement in any measure of cardiac function was observed at any time. We conclude that cultured BMSCs are not the optimal cell population to treat the infarcted heart. 相似文献
107.
Greg Parsonage Andrew Filer Magdalena Bik Debbie Hardie Sian Lax Katherine Howlett Leigh D Church Karim Raza See-Heng Wong Emily Trebilcock Dagmar Scheel-Toellner Mike Salmon Janet M Lord Christopher D Buckley 《Arthritis research & therapy》2008,10(2):1-12
Introduction
A surprising feature of the inflammatory infiltrate in rheumatoid arthritis is the accumulation of neutrophils within synovial fluid and at the pannus cartilage boundary. Recent findings suggest that a distinct subset of IL-17-secreting T-helper cells (TH17 cells) plays a key role in connecting the adaptive and innate arms of the immune response and in regulating neutrophil homeostasis. We therefore tested the hypothesis that synovial fibroblasts bridge the biological responses that connect TH17 cells to neutrophils by producing neutrophil survival factors following their activation with IL-17.Methods
IL-17-expressing cells in the rheumatoid synovium, and IL-17-expressing cells in the peripheral blood, and synovial fluid were examined by confocal microscopy and flow cytometry, respectively. Peripheral blood neutrophils were cocultured either with rheumatoid arthritis synovial fibroblasts (RASF) or with conditioned medium from RASF that had been pre-exposed to recombinant human IL-17, TNFα or a combination of the two cytokines. Neutrophils were harvested and stained with the vital mitochondrial dye 3,3'-dihexyloxacarbocyanine iodide before being enumerated by flow cytometry.Results
TH17-expressing CD4+ cells were found to accumulate within rheumatoid synovial tissue and in rheumatoid arthritis synovial fluid. RASF treated with IL-17 and TNFα (RASFIL-17/TNF) effectively doubled the functional lifespan of neutrophils in coculture. This was entirely due to soluble factors secreted from the fibroblasts. Specific depletion of granulocyte–macrophage colony-stimulating factor from RASFIL-17/TNF-conditioned medium demonstrated that this cytokine accounted for approximately one-half of the neutrophil survival activity. Inhibition of phosphatidylinositol-3-kinase and NF-κB pathways showed a requirement for both signalling pathways in RASFIL-17/TNF-mediated neutrophil rescue.Conclusion
The increased number of neutrophils with an extended lifespan found in the rheumatoid synovial microenvironment is partly accounted for by IL-17 and TNFα activation of synovial fibroblasts. TH17-expressing T cells within the rheumatoid synovium are likely to contribute significantly to this effect. 相似文献108.
109.
Kin selection advantages are usually accrued by individualsthat associate with close relatives. But aggregation may alsobe costly, by increasing the risk of predation or resource competition,for example. As a result, individuals should increase theirinclusive fitness by trading the costs and benefits of kin associationand aggregation. Studies of kin selection to date have focusedon situations where there is ample opportunity for kin-biasedbehavior and therefore for the formation of kin groups. Herewe used juvenile Atlantic salmon to test an alternative strategy:that under conditions where the potential for kin-biased behavioris negligible, individuals should, when aggregating, avoid ratherthan associate with kin to avoid imposing the costs of aggregationupon close relatives. By testing salmon during winter, whenjuveniles shelter inactively in streambed refuges, we testedwhether individuals associate with or avoid their siblings ata time when the opportunity for kin-directed behaviors is restricted.Our results provide the first evidence of kin avoidance in nonreproductiveanimals studied under semi-natural conditions. 相似文献
110.
Mikko Tiusanen Tea Huotari Paul D. N. Hebert Tommi Andersson Ashley Asmus Joël Bêty Emma Davis Jennifer Gale Bess Hardwick David Hik Christian Krner Richard B. Lanctot Maarten J. J. E. Loonen Rauni Partanen Karissa Reischke Sarah T. Saalfeld Fanny Senez‐Gagnon Paul A. Smith Jn ulavík Ilkka Syvnper Christine Urbanowicz Sian Williams Paul Woodard Yulia Zaika Tomas Roslin 《Molecular ecology》2019,28(2):318-335