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Invasive Strategy (invasive + strategy)
Selected AbstractsPhotosynthesis and water-use efficiency: A comparison between invasive (exotic) and non-invasive (native) speciesAUSTRAL ECOLOGY, Issue 1 2008KATE G. MCALPINE Abstract Invasive species have been hypothesized to out-compete natives though either a Jack-of-all-trades strategy, where they are able to utilize resources effectively in unfavourable environments, a master-of-some, where resource utilization is greater than its competitors in favourable environments, or a combination of the two (Jack-and-master). We examined the invasive strategy of Berberis darwinii in New Zealand compared with four co-occurring native species by examining germination, seedling survival, photosynthetic characteristics and water-use efficiency of adult plants, in sun and shade environments. Berberis darwinii seeds germinated more in shady sites than the other natives, but survival was low. In contrast, while germination of B. darwinii was the same as the native species in sunny sites, seedling survival after 18 months was nearly twice that of the all native species. The maximum photosynthetic rate of B. darwinii was nearly double that of all native species in the sun, but was similar among all species in the shade. Other photosynthetic traits (quantum yield and stomatal conductance) did not generally differ between B. darwinii and the native species, regardless of light environment. Berberis darwinii had more positive values of ,13C than the four native species, suggesting that it gains more carbon per unit water transpired than the competing native species. These results suggest that the invasion success of B. darwinii may be partially explained by combination of a Jack-of-all-trades scenario of widespread germination with a master-of-some scenario through its ability to photosynthesize at higher rates in the sun and, hence, gain a rapid height and biomass advantage over native species in favourable environments. [source] Percutaneous coronary intervention using a virtual 3-Fr guiding catheter,CATHETERIZATION AND CARDIOVASCULAR INTERVENTIONS, Issue 7 2010Shingo Mizuno MD Abstract Background: We have recently reported a novel percutaneous coronary intervention (PCI) system using a hydrophilic-coated sheathless guiding catheter (Virtual 3-Fr, Medikit, Tokyo, Japan), which provides us with less invasive angioplasty and a puncture site injury equivalent to a conventional 3-Fr introducer sheath. Here, we report the initial results of PCI using this novel system. Methods: A total of 36 coronary artery lesions of 27 patients were treated by using a virtual 3-Fr PCI system. Procedural outcomes of virtual 3-Fr PCI were retrospectively evaluated. Results: The mean age was 73.0 ± 8.7 years (range, 46,84 years), and 15 were men (56%). Access sites included the radial artery in 18 patients (67%), the brachial artery in eight patients (30%), and the femoral artery in 1 patients (4%). Among 36 lesions, seven were chronic total occlusions, and a virtual 3-Fr PCI was successful in 33 lesions (92%). Among the successfully treated 33 lesions, coronary stents were deployed in 32 (97%), and intravascular ultrasound examination was performed in 19 (58%). Hemostasis was achieved immediately after PCIs in all cases. No access-site related complications including radial artery occlusion were observed. Conclusions: The performance of a virtual 3-Fr PCI system appears to be comparable to one using a regular 5-Fr guiding catheter while the puncture-site damage remains equivalent to that of a 3-Fr introducer sheath. Virtual 3-Fr PCI may have a potential to serve as a minimally invasive strategy for the treatment of coronary artery diseases. © 2010 Wiley-Liss, Inc. [source] Therapeutic strategies, immediate and mid-term outcomes in non-ST-segment elevation acute coronary syndromes with respect to age: A single-center registry of 488 consecutive patientsCLINICAL CARDIOLOGY, Issue 8 2004Mario Leoncini M.D. Abstract Background: Elderly patients with non-ST-elevation acute coronary syndromes (NSTE-ACS) may receive benefit from an early invasive strategy. However, aged patients often suffer from comorbidities that may contraindicate an invasive approach and affect prognosis adversely. The impact of comorbidities on an invasive approach to NSTE-ACS in the elderly has not been fully investigated. Hypothesis: This study sought to examine the outcome of an unselected population of patients with NSTE-ACS stratified according to age and treatment approach. Methods: The feasibility and efficacy of an invasive strategy for NSTE-ACS and the 6-month outcome were assessed in 253 unselected consecutive patients , 70 years (elderly) and compared with those of 235 unselected consecutive patients < 70 years. Results: Angiography was not performed in 69 patients (86% , 70 years) because of contraindications. In the whole population, the 6-month event rate was significantly higher in elderly compared with younger patients (22 vs. 14%; odds ratio 1.8, 95% confidence interval 1.1-2.9; p<0.02). This difference was driven by the high event rate observed in the elderly with contraindications to angiography (47 vs. 16% in the elderly treated invasively; p < 0.002). On the other hand, no significant difference was observed in the 6-month event rate between elderly and younger patients undergoing an invasive approach (16 vs. 13%; p=0.36). Contraindications to angiography,namely, creatinine , 1.5 mg/dl and elevated troponin I at admission,were the only independent predictors of 6-month outcome. Conclusions: The invasive approach was feasible in 77% of patients , 70 years. Those with contraindications to angiography showed a poor mid-term prognosis. The early invasive strategy was associated with more favorable outcomes regardless of age. [source] | ||||||||||