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31.
The introduction of mammalian predators has been detrimental to many native birds in New Zealand. One solution to this problem
has been the creation of “mainland islands” in which exotic predators are systematically removed. Although mainland islands
have been effective in increasing some native bird populations, few studies have measured the effect of predator-control on
nest success nor what effect control measures have on sympatric populations of introduced birds. We measured the effect of
predator-control on nest survival rates in both native and introduced passerines in a mainland island near Kaikoura, New Zealand.
Nest survival was significantly higher in Waimangarara Bush (the site with experimental predator-control) than in Kowhai Bush
(the site with no predator-control) and this pattern was found in both groups of birds. However, mammalian predator-control
increased nest success of native species significantly more than nest success of introduced species. This suggests that native
birds benefit disproportionately from control of introduced predators, most likely because they lack behavioural defences
against mammalian predators that are present among the introduced birds. 相似文献
32.
M Imboden A Nieters AJ Bircher M Brutsche N Becker M Wjst U Ackermann-Liebrich W Berger NM Probst-Hensch 《Clinical and molecular allergy : CMA》2006,4(1):1-9
Background
Avoidance of allergens is still recommended as the first and best way to prevent allergic illnesses and their comorbid diseases. Despite a variety of attempts there has been very limited success in the area of environmental control of allergic disease. Our objective was to identify a non-invasive, non-pharmacological method to reduce indoor allergen loads in atopic persons' homes and public environments. We employed a novel in vivo approach to examine the possibility of using aluminum sulfate to control environmental allergens.Methods
Fifty skin test reactive patients were simultaneously skin tested with conventional test materials and the actions of the protein/glycoprotein modifier, aluminum sulfate. Common allergens, dog, cat, dust mite, Alternaria, and cockroach were used in the study.Results
Skin test reactivity was significantly reduced by the modifier aluminum sulfate. Our studies demonstrate that the effects of histamine were not affected by the presence of aluminum sulfate. In fact, skin test reactivity was reduced independent of whether aluminum sulfate was present in the allergen test material or removed prior to testing, indicating that the allergens had in some way been inactivated.Conclusion
Aluminum sulfate was found to reduce the in vivo allergic reaction cascade induced by skin testing with common allergens. The exact mechanism is not clear but appears to involve the alteration of IgE-binding epitopes on the allergen. Our results indicate that it may be possible to diminish the allergenicity of an environment by application of the active agent aluminum sulfate, thus producing environmental control without complete removal of the allergen. 相似文献33.
Unusual growth pattern in the Frasnian alveolitids (Tabulata) from the Holy Cross Mountains (Poland)
Abstract: Growth periodicity is a phenomenon occurring in fossil and modern corals. The most apparent feature is growth banding, and environmental changes are broadly accepted as controls on this phenomenon. If environment controls the growth, then all corallites within a colony should repeat the same growth pattern, as individuals are clones and must have shared the same environment. A study on several species of Alveolitidae (Anthozoa, Tabulata) from the Late Devonian (Early Frasnian) of the Holy Cross Mountains (Poland) shows that the growth pattern varies between neighbouring individuals within the same corallum. This contradicts observations of closely related Favositida as demonstrated on Pachyfavosites sp. from the Givetian of Avesnois, France, where neighbouring individuals repeat the same pattern. Therefore, environmental control on growth rhythm in Alveolitidae can be excluded; the causes of differences between individuals remain unknown. 相似文献
34.
McManus DD Lyass A Ingelsson E Massaro JM Meigs JB Aragam J Benjamin EJ Vasan RS 《Obesity (Silver Spring, Md.)》2012,20(9):1882-1886
Obesity is associated with pathological cardiac remodeling and risk of heart failure (HF). Adipocytokines (ADKs) may mediate the increased risk of cardiovascular disease associated with excess adiposity. Yet data relating ADKs to cardiac remodeling phenotypes are sparse. We related two circulating ADKs, resistin and adiponectin, to three important echocardiographic markers of cardiac remodeling, left ventricular mass (LVM), left atrial diameter (LAD), and LV fractional shortening (LVFS) in 2,615 participants (mean age 61 years, 55% women) in the Framingham Offspring Study. Adiponectin concentrations were inversely related to LVM in multivariable linear regression models adjusting for key clinical correlates including BMI (regression coefficient per s.d.-increment in ln-adiponectin = -3.37, P = 0.02; P for trend across quartiles = 0.02). Adiponectin was not associated with LAD or LVFS (P > 0.56). Resistin concentrations were inversely related to LVFS (regression coefficient per s.d.-increment in ln-resistin = -0.01, P = 0.03; P for trend across quartiles = 0.04). Resistin was not associated with LVM or LAD (P > 0.05). In our moderate-sized, community-based sample, higher circulating concentrations of adiponectin and resistin were associated with lower LVM and lower LVFS, respectively. In conclusion, these associations identify potential mechanisms by which excess adiposity may mediate adverse cardiac remodeling and HF risk. 相似文献
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Massaro D Massaro GD 《American journal of physiology. Lung cellular and molecular physiology》2008,294(5):L991-L997
Diminished lung function, indicated by a low forced expiratory volume in one second (FEV1), and short physical stature, predict early mortality from all causes, including cardiovascular, among smokers and never smokers. The basis for these associations is unclear, and, it is not known if there is a pulmonary morphological component to the relationship between low FEV1 and early death in a general population. Some apolipoprotein E genotypes also predict atherosclerosis and early mortality. These considerations led us to examine the Apoe(tm1Unc) (Apoe) mouse, in which the apolipoprotein E gene is deleted, and that develops dyslipidemia, atherosclerosis at an early age, and has a shorter life span than the founder wild-type (wt) strain. We asked if Apoe mice have a morphological or functional pulmonary phenotype. We measured the size, number, and surface area of pulmonary gas-exchange units (alveoli) and mechanical properties of the lung. Compared with wt mice, Apoe mice had: 1) diminished developmental alveologenesis, 2) increased airway resistance in early adulthood, 3) high lung volume and high dynamic and static compliance in later adulthood, 4) more rapid loss of lung recoil with age, and 5) were less long than wt mice. These findings in mice indicate the association of a low FEV1 with early death in humans may have developmental, and accelerated ageing, related pulmonary components, and that dietary, genetic, or dietary and genetic influences, on lipid metabolism may be an upstream cause of inflammation and oxidative stress, currently considered to be major risk factors for COPD. 相似文献
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Hyperinsulinemia is an independent risk factor for cardiovascular events and may contribute to cardiovascular disease. Low-grade chronic inflammation has been implicated in the pathogenesis of atherosclerosis. We aimed at determining the impact of pathophysiologically high insulin concentrations on cytokine-induced endothelial activation in human umbilical vein endothelial cells (HUVEC). HUVEC were incubated with insulin (0-24 h)+/-tumor necrosis factor (TNF)-alpha or lipopolysaccharide (LPS). At pathophysiological/pharmacological concentrations (10(-9)-10(-7) mol/L), insulin selectively induced VCAM-1 expression and potentiated the effects of TNF-alpha andLPS, effects reverted by the proteasome inhibitor lactacystin. Compared with TNF-alpha alone, insulin+TNF-alpha doubled U937 cell adhesion. Insulin markedly increased TNF-alpha-induced NF-kappaB activation and induced phosphorylated IkappaB-alpha accumulation. Therefore, hyperinsulinemia enhances cytokine-induced VCAM-1 expression in endothelial cells, thus potentially contributing to detrimental effects of other inflammatory stimuli on atherogenesis. 相似文献
40.