SoilTemp: A global database of near-surface temperature

Current analyses and predictions of spatially explicit patterns and processes in ecology most often rely on climate data interpolated from standardized weather stations. This interpolated climate data represents long-term average thermal conditions at coarse spatial resolutions only. Hence, many climate-forcing factors that operate at fine spatiotemporal resolutions are overlooked. This is particularly important in relation to effects of observation height (e.g. vegetation, snow and soil characteristics) and in habitats varying in their exposure to radiation, moisture and wind (e.g. topography, radiative forcing or cold-air pooling). Since organisms living close to the ground relate more strongly to these microclimatic conditions than to free-air temperatures, microclimatic ground and near-surface data are needed to provide realistic forecasts of the fate of such organisms under anthropogenic climate change, as well as of the functioning of the ecosystems they live in. To fill this critical gap, we highlight a call for temperature time series submissions to SoilTemp, a geospatial database initiative compiling soil and near-surface temperature data from all over the world. Currently, this database contains time series from 7,538 temperature sensors from 51 countries across all key biomes. The database will pave the way toward an improved global understanding of microclimate and bridge the gap between the available climate data and the climate at fine spatiotemporal resolutions relevant to most organisms and ecosystem processes.

Ligands for the benzodiazepine binding site--a survey

Gamma-Aminobutyric acid (GABA) is the major inhibitory neurotransmitter in the mammalian Central Nervous System (CNS). GABA participates in the regulation of neuronal excitability through interaction with specific membrane proteins (the GABAA receptors). The binding of GABA to these postsynaptic receptors, results in an opening of a chloride channel integrated in the receptor which allows the entry of Cl- and consequently leads to hyperpolarization of the recipient cell. The action of GABA is allosterically modulated by a wide variety of chemical entities which interact with distinct binding sites at the GABAA receptor complex. One of the most thoroughly investigated modulatory site is the benzodiazepine binding site. The benzodiazepines constitute a well-known class of therapeutics displaying hypnotic, anxiolytic and anticonvulsant effects. Their usefulness, however, is limited by a broad range of side effects comprising sedation, ataxia, amnesia, alcohol and barbiturate potentiation, tolerance development and abuse potential. Consequently, there has been an intensive search for modulatory agents with an improved profile, and a diversity of chemical entities distinct from the benzodiazepines, but with GABA modulatory effects have been identified. The existence of endogenous ligands for the GABAA receptor complex beside GABA has often been described, but their role in the regulation of GABA action is still a matter of controversy. The progress of molecular biology during the last decade has contributed enormously to the understanding of benzodiazepine receptor pharmacology. A total of 14 GABAA receptor subunits have been cloned from mammalian brain and have been expressed/co-expressed in stable cell lines. These transfected cells constitute an important tool in the characterization of subtype selective ligands. In spite of the rapidly expanding knowledge of the molecular and pharmacological mechanisms involved in GABA/benzodiazepine related CNS disorders, the identification of clinically selective acting drugs is still to come.

Ligands for the Benzodiazepine Binding Site - a Survey

Abstract:

y-Aminobutyric acid (GABA) is the major inhibitory neurotransmitter in the mammalian Central Nervous System (CNS). GABA participates in the 1·egulation of neuronal excitability through interaction with specific membrane proteins (the GABAA receptors). The binding of GABA to these postsynaptic receptors, results in an opening of a chloride channel integrated in the receptor which allows the entry of c1- and consequently leads to hyperpolarization of the recipient cell. The action of GABA is allosterically modulated by a wide variety of chemical entities which interact with distinct binding sites at the GABAA receptor complex. One of the most thoroughly investigated rnodulatory site is the benzodiazepin binding site. The benzodiazepines constitute a well-known class of therapeutics displaying hypnotic, anxiolytic and anticonvulsant effects. Their usefulness, however, is limited by a broad range of side effects comprising sedation, ataxia, amnesia, alcohol and barbiturate potentiation, tolerance development and abuse potential. Consequently, there has been an intensive search for modulatory agents with an improved profile, and a diversity of chemical entities distinct from the benzodiazepines. but with GABA modulatory effects have been identified. The existence of endogenous ligands for the GABAA receptor complex beside GABA has often been described, but their role in the regulation of GABA action is still a matter of controversy. The progress of molecular biology during the last decade has contributed enormously to the understanding of benzodiazepine receptor pharmacology. A total of 14 GABAA receptor subunits have been cloned from mammalian brain and have been expressed/co-expressed in stable cell lines. These transfected cells constitute an important tool in the characterization of subtype selective ligands. In spite of the rapidly expanding knowledge of the molecular and pharmacological mechanisms involved in GABA/benzodiazepine related CNS disorders. the identification of clinically selective acting drugs is still to come.

3,4-O-diacetylisoproterenol. Preparation, structure proof, and beta-receptor effect

Direct acetylation of isoproterenol by selective O-acetylation using CH3COCl/CF3COOH was shown to lead to the formation of 2-(3,4-diacetoxyphenyl)-2-chloro-N-isopropyl-1-ethanamine and not to 3,4-O-diacetylisoproterenol. The latter was prepared by reduction of 3,4-diacetoxy(2-isopropylamino)acetophenone and its structure confirmed by IR, 1H, 13C NMR, mass spectral, and elemental analysis. The two compounds were tested for activity on beta-receptors. Efficacy and affinity on beta 1-receptors were found identical with the effect of isoproterenol. So was efficacy on beta2-receptors, while affinity was lower for the chloro compounds than for isoproterenol and diacetylisoproterenol which exhibited identical affinity.