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1.
Sci Total Environ ; 894: 164769, 2023 Oct 10.
Article in English | MEDLINE | ID: mdl-37301404

ABSTRACT

Wetlands fulfil a number of functions in the landscape, especially non-productive ones. Information on landscape and biotope changes is important not only from a theoretical point of view for understanding the forces and pressures that cause changes in the landscape, but also from a practical point of view, as we can take inspiration from history when planning the landscape. The main goal of this study is to analyse the dynamics and trajectories of changes in wetlands, including testing the influence of the main natural conditions (climate, geomorphology) on their changes, for a large area of 141 cadastral territories (1315 km2), which will allow the results to be sufficiently generalized. The results of our study confirmed the global trend of rapid wetland loss, with almost three quarters of wetlands disappearing, mostly on arable land (37 %). The results of the study are of great importance in the field of the ecology of landscapes and wetlands, both in the national and international context, not only because they make it possible to understand the regularities and forces that affect changes in wetlands and landscapes, but also have significance due to the methodology. The specific methodology and procedure are based on the application of advanced GIS functions (Union and Intersect functions) to identify the location and area of individual change dynamics and types of wetland (new, extinct, continuous), using accurate old large-scale maps and aerial photographs. The proposed and tested methodological procedure can generally be used for wetlands in other locations, but also for studying the dynamics of changes and trajectories of other biotopes in the landscape. The greatest potential for using the results of this work in the field of environmental protection is the possibility of using the places of extinct wetlands for their restoration.


Subject(s)
Ecosystem , Wetlands , Czech Republic , Ecology , Conservation of Natural Resources
2.
Biochem Pharmacol ; 33(16): 2653-6, 1984 Aug 15.
Article in English | MEDLINE | ID: mdl-6087836

ABSTRACT

The phospholipases controlling the release of arachidonic acid in mouse peritoneal macrophages have been shown to be stimulated by the natural psychoactive cannabinoids. A close correlation was observed between the potencies of these substances in elevating arachidonate levels in vitro and the reported activities in a behavioral assay in monkeys and in producing a "high" in humans. The order of activity with the macrophages was delta 1-tetrahydrocannabinol (delta 1-THC) greater than 7-OH-delta 1-THC greater than 6 alpha-OH-delta 1-THC greater than 6 beta-delta 1-THC much greater than delta 6-THC-7-oic acid. It is suggested that this effect, which has now been shown in several diverse cell types, may serve as a model for studying the mechanism of action of THC.


Subject(s)
Arachidonic Acids/metabolism , Dronabinol/pharmacology , Macrophages/metabolism , Animals , Arachidonic Acid , Ascitic Fluid , Dronabinol/metabolism , In Vitro Techniques , Lipoxygenase/analysis , Male , Mice , Mice, Inbred Strains , Structure-Activity Relationship
3.
Mol Pharmacol ; 23(1): 121-6, 1983 Jan.
Article in English | MEDLINE | ID: mdl-6865895

ABSTRACT

Earlier findings indicated that several other cannabinoids in addition to delta 1-tetrahydro-cannabinol (THC) were able to stimulate the synthesis of prostaglandins in cell culture systems. The present study was initiated to delineate the structural requirements for this effect within the cannabinoid series. Among the primary cannabinoids, we found that the trend was for more planar structures to show greater activity. In the case of THC metabolites, the order of activity was delta 1-THC greater than 7-oxo-delta 1, 6-THC greater than 7-OH-delta 1-THC greater than 3"-OH-delta 1-THC = 6 beta-OH-delta 1-THC = 6 alpha-OH-delta 1-THC greater than delta 1, 6-THC-7-oic acid. The latter sequence compares favorably with the available data on the behavioral assay in the rhesus monkey and the subjective "high" in humans. We also observed a good correlation between the release of arachidonic acid and the production of prostaglandin E, over a series of eight cannabinoids. This gives further support that the site of action in this effect is the elevation of activity of the phospholipase(s) responsible for supplying precursor arachidonic acid for prostaglandin synthesis.


Subject(s)
Cannabinoids/pharmacology , Fibroblasts/drug effects , Prostaglandins/biosynthesis , Arachidonic Acids/metabolism , Cell Line , Cell Survival/drug effects , Fetus , Fibroblasts/metabolism , Humans , Male , Prostaglandins E/biosynthesis , Structure-Activity Relationship
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