The Scent of the Fly

(Z)-4-undecenal (Z4-11Al) is the volatile pheromone produced by females of the vinegar fly Drosophila melanogaster. Female flies emit Z4-11Al for species-specific communication and mate-finding. A sensory panel finds that synthetic Z4-11Al has a characteristic flavour, which can be perceived even at the small amounts produced by a single female fly. Since only females produce Z4-11Al, and not males, we can reliably distinguish between single D. melanogaster males and females, according to their scent. Females release Z4-11Al at 2.4 ng/h and we readily sense 1 ng synthetic Z4-11Al in a glass of wine (0.03 nmol/L), while a tenfold concentration is perceived as a loud off-flavour. This corroborates the observation that a glass of wine is spoilt by a single D. melanogaster fly falling into it, which we here show is caused by Z4-11Al. The biological role of Z4-11Al or structurally related aldehydes in humans and the basis for this semiochemical convergence remains yet unclear.

Conservation significance of intact forest landscapes in the Scandinavian Mountains Green Belt

Context: As forest harvesting remains high, there is a crucial need to assess the remaining large, contiguous and intact forests, regionally, nationally and globally. Objectives: Our objective was to analyze the spatial patterns and structural connectivity of intact and primary forests in northern Sweden with focus on the Scandinavian Mountain region; one of the few remaining large European intact forest landscapes. Methods: Over 22 million ha with 14.5 million ha boreal and subalpine forest and with data consisting of a 60-70 year retrospective sequence, we analyzed distribution, density and connectivity of forests that have not been clear cut, using moving window and landscape analyzes derived from Circuitscape. Results: We revealed a contiguous, connected and semi-connected intact forest landscape forming a distinct Green Belt south to north along the mountain range. Almost 60% of the forestland remains intact, including contiguous clusters 10,000 ha and larger. The connectivity is particularly high in protected areas with primary forests outside contributing substantially to overall connectivity. We found gaps in connectivity in the southern parts, and furthermore low or absent connectivity across the whole inland and coastal areas of northern Sweden. Conclusions: Given its ecological values, the Scandinavian Mountains Green Belt is a key entity supporting ecological legacies, boreal biodiversity and ecosystem services, resilience and adaptive capacity, which needs to be safeguarded for the future. On the very large areas outside the mountain region, forestlands are severely fragmented, connectivity values are lost, and forest landscape restoration is needed for conservation and functional green infrastructure.

Biochemical and pharmacological role of A1adenosine receptors and their modulation as novel therapeutic strategy

Adenosine, the purine nucleoside, mediates its effects through activation of four G-protein coupled adenosine receptors (ARs) named as A1, A2A, A2Band A3. In particular, A1ARs are distributed through the body, primarily inhibitory in the regulation of adenylyl cyclase activity and able to reduce the cyclic AMP levels. Considerable advances have been made in the pharmacological and molecular characterization of A1ARs, which had been proposed as targets for the discovery and drug design of antagonists, agonists and allosteric enhancers. Several lines of evidence indicate that adenosine interacting with A1ARs may be an endogenous protective agent in the human body since it prevents the damage caused by various pathological conditions, such as in ischemia/hypoxia, epileptic seizures, excitotoxic neuronal injury and cardiac arrhythmias in cardiovascular system. It has also been reported that one of the most promising targets for the development of new anxiolytic drugs could be A1ARs, and that their activation may reduce pain signaling in the spinal cord. A1AR antagonists induce diuresis and natriuresis in various experimental models, mediating the inhibition of A1ARs in the proximal tubule which is primarily responsible for reabsorption and fluid uptake. In addition, the results of various studies indicate that adenosine is present within pancreatic islets and is implicated through A1ARs in the regulation of insulin secretion and in glucose concentrations. In the present paper it will become apparent that A1ARs could be implicated in the pharmacological treatment of several pathologies with an important influence on human health