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791.
792.
《Cytotherapy》2014,16(9):1270-1279
Background aimsThe purpose of this study was to evaluate the effect of autologous bone marrow mononuclear cells (BM-MNCs) on symptoms and perfusion indices in severely symptomatic patients with peripheral arterial disease (PAD) without further option for endovascular or surgical revascularization.MethodsOnly patients with severe symptomatic PAD (Fontaine class IIb-IV, Rutherford category 3–6) not amenable for revascularization were treated. Bone marrow from both cristae iliacae was harvested; MNCs were isolated by the Ficoll density-gradient method and transplanted by means of intra-arterial and intramuscular injection in the index limb. Functional (pain score, ulcer healing, maximum walking distance) and perfusion indices such as ankle-brachial-index and transcutaneous oxygen pressure were documented before and after BM-MNC therapy. Additionally, serum concentration of C-reactive protein and interleukin-6 were measured as markers of inflammation before and after BM-MNC treatment.ResultsSixteen consecutive patients (four women; mean age, 63.0 ± 13 years) were treated with a mean dose of 4.2 ± 2.2 × 108 BM-MNCs. At 6 months' follow-up, ankle-brachial-index, transcutaneous oxygen pressure and maximum walking distance significantly increased, whereas C-reactive protein and interleukin-6 conversely decreased (P < 0.01 versus baseline values), resulting in 88% limb salvage, 75% pain reduction and 71% complete wound healing and/or reduction of ulcer size. One major and one minor amputation were performed, both in patients with Rutherford category 6.ConclusionsAutologous BM-MNC therapy in patients with end-stage PAD improves tissue perfusion indices and decreases markers of inflammation. If our observations could be confirmed by large-scale, randomized controlled trials, BM-MNC transplantation could become an alternative therapeutic option for patients with end-stage PAD. 相似文献
793.
Locomotor capacity and dominance in male lizards Lacerta monticola: a trade‐off between survival and reproductive success? 总被引:1,自引:0,他引:1
Pilar López José Martín 《Biological journal of the Linnean Society. Linnean Society of London》2002,77(2):201-209
Trade-offs between reproduction and survival are important determinants of life-history characteristics of lizards. Organisms cannot increase the allocation of limited resources to reproduction without diverting a proportional amount of energy from another trait. Locomotor performance is an ecologically relevant trait that potentially influences survival by affecting the ability to escape from predators. Most studies have used female lizards as subjects because pregnancy is known to reduce their locomotor abilities, whereas little is known on costs of reproduction in males. In this study we suggest that in males of the lizard Lacerta monticola reproductive investment in morphological traits that confer dominance (i.e. head size) might lead to a low probability of survival by decreasing investment in other traits that affect locomotor performance (i.e. limb symmetry). We staged laboratory agonistic encounters between males and measured their morphology and burst speed on a race track to examine possible relationships between morphology, social dominance and locomotor capacity. Our results indicate that social dominance was positively related to relative head height, and that escape speed was negatively related to levels of fluctuating asymmetry in femur length, but also negatively related to relative head height. Males with greater relative head height also had more asymmetrical femurs, thus dominant males suffered a decrease in locomotor performance. Males with higher heads tend to dominate male–male interactions and hence may gain access to reproductive females, thus increasing their current reproduction success. However, this might occur at the expense of future survivorship mediated by a decrease in escape speed. Therefore, in male L. monticola there might be a trade-off between current reproductive success and survival. © 2002 The Linnean Society of London, Biological Journal of the Linnean Society , 2002; 77 , 201–209. 相似文献