The effect of aging and acute treatment with acetyl-
l-carnitine on the pyruvate transport and oxidation in rat heart mitochondria was studied. The activity of the pyruvate carrier as well as the ...rates of pyruvate-supported respiration were both depressed (around 40%) in heart mitochondria from aged rats, the major decrease occurring during the second year of life. Administration of acetyl-
l-carnitine to aged rats almost completely restored the rates of these metabolic functions to the level of young control rats. This effect of acetyl-
l-carnitine was not due to changes in the content of pyruvate carrier molecules. The heart mitochondrial content of cardiolipin, a key phospholipid necessary for mitochondrial substrate transport, was markedly reduced (approximately 40%) in aged rats. Treatment of aged rats with acetyl-
l-carnitine reversed the age-associated decline in cardiolipin content. As the changes in cardiolipin content were correlated with changes in rates of pyruvate transport and oxidation, it is suggested that acetyl-
l-carnitine reverses the age-related decrement in the mitochondrial pyruvate metabolism by restoring the normal cardiolipin content.
This nonrandomized study compared the virologic and immunologic responses to potent regimens containing either efavirenz or nevirapine after considering potential systematic differences between ...patients receiving these drugs. Virologic failure was defined as the first of 2 consecutive measurements of virus load > 500 human immunodeficiency virus RNA copies/mL. Of the 694 patients included in the analysis, 460 (66.3%) started nevirapine and 234 (33.7%) started efavirenz. The adjusted relative hazard of virologic failure for patients who started nevirapine, compared with those who started efavirenz, was 2.08 (95% confidence interval, 1.37–3.15; P = .0006). In addition, patients receiving efavirenz tended to recover 5 CD4 cells/µL more per quarter (P = .05). Although comparisons of drug efficacy in nonrandomized studies should be viewed with caution, no results from randomized controlled comparisons of these drugs are thought to be available. The findings of this study are in agreement with those of other observational studies.
The effect of aging and treatment with acetyl-
l-carnitine on the activity of cytochrome oxidase and adenine nucleotide translocase in rat heart mitochondria was studied. It was found that the ...activity of both these mitochondrial protein systems was reduced (by around 30%) in aged animals. Treatment of aged rats with acetyl-
l-carnitine almost completely reversed this effect. Changes in the mitochondrial cardiolipin content appear to be responsible for these effects of acetyl-
l-carnitine.
Age-related changes in mitochondrial fatty acids metabolism may underlie the progressive decline in cardiac function. The effect of aging and acute treatment with acetyl-L-carnitine on fatty acids ...oxidation and on carnitine-acylcarnitine translocase activity in rat heart mitochondria was studied. Rates of palmitoylcarnitine supported respiration as well as carnitine-carnitine and carnitine-palmitoylcarnitine exchange reactions were all depressed (approx. 35%) in heart mitochondria from aged rats. These effects were almost completely reversed following treatment of aged rats with acetyl-L-carnitine. Heart mitochondrial cardiolipin content was significantly reduced (approx. 38%) in aged rats. Treatment of aged rats with acetyl-L-carnitine restored the level of cardiolipin to that of young rats. It is suggested that acetyl-L-carnitine is able to reverse age-related decrement in mitochondrial carnitine-acylcarnitine exchange activity by restoring the normal cardiolipin content.
The maintenance of ecosystem services is the basic guarantee of environmental security that, in an objective sense, aims to evaluate the level of threats to actual acquired goods and services and, in ...a subjective sense, the level of consciousness and fear that such services will be attacked and possibly lost. To this purpose the aim of this research is: (1) to assess the temporal dynamics of land use and land cover mosaics, and indirectly of ecosystem services, using the economic valuations as surrogates; (2) to verify if the environmental conservation policies can foster ecosystem services; and, since it is still necessary to foster users’ perception of ecosystem services in order to reduce their fragility, (3) to compare the results coming from objective and subjective analyses. This is overriding in the case of tourism, where the attarctiveness of tourist destinations will depend on the maintenance of recreational ecosystem services based on both natural and cultural heritages. This research highlights the need for a dynamic and continuous inter-comparison between objective and subjective analyses in order to reduce progressively their possible discordance and, consequently, increase environmental security for a more effective adaptive management of ecosystem goods and services.
Keywords: Ecosystem goods and services; environmental security; socioeconomic valuation
Environmental security, as the opposite of environmental fragility (vulnerability), is multilayered, multi-scale and complex, existing in both the objective realm of biophysics and society, and the ...subjective realm of individual human perception. For ecological risk assessments (ERAs), the relevant objects of environmental security are social-ecological landscapes (SELs). ERAs, in this case, are less precise than traditional ERAs, but provide results that are more comprehensive and understandable by stakeholders. In this paper, we detect and quantify the scales and spatial patterns of human land use as ecosystem disturbances at different hierarchical levels in a panarchy of SELs by using a conceptual framework that characterizes multi-scale disturbance patterns exhibited on satellite imagery over a four-year time period in Apulia (South Italy). Multi-scale measurements of the composition and spatial configuration of disturbance are the basis for evaluating fragility through multiscale disturbance profiles, and the identification of scale mismatches revealed by trajectories diverging from the global profile to local spatial patterns. Scale mismatches of disturbances in space and time determine the role of land use as a disturbance source or sink, and may govern the triggering of landscape changes affecting regional biodiversity. This study clarifies the potential roles for environmental security of natural areas and permanent cultivations (olive groves and vineyards) in buffering Mediterranean landscape disturbance dynamics and compensating for disturbances across the whole panarchy of Apulia, allowing for potential landscape planning of disturbance.
Keywords: Environmental security; multi-scale disturbance; scale mismatches; socialecological landscapes
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