The Potential Role of CO2 in Initiation and Maintenance of Estivation in the Land Snail Helix lucorum

2007 ◽  
Vol 80 (1) ◽  
pp. 113-124 ◽  
Author(s):  
Basile Michaelidis ◽  
Dimitra Vavoulidou ◽  
Jenia Rousou ◽  
Hans O. Pörtner
Keyword(s):  
Potential Role ◽  
Land Snail ◽  
Helix Lucorum

Analysis of monoamines, adenosine and GABA in tissues of the land snail Helix lucorum and lizard Agama stellio stellio during hibernation

2002 ◽  
Vol 205 (8) ◽  
pp. 1135-1143 ◽  
Author(s):  
Basile Michaelidis ◽  
Nikolaos S. Loumbourdis ◽  
Elizabeth Kapaki
Keyword(s):  
Acetic Acid ◽  
Neuronal Activity ◽  
Marked Decrease ◽  
Land Snail ◽  
Main Metabolite ◽  
Helix Lucorum ◽  
Low Levels ◽  
The Brain

SUMMARY The aim of the present study was to determine the levels of monoamines,GABA and adenosine in the brain, heart and haemolymph of the land snail Helix lucorum and in the brain, heart and blood of lizard Agama stellio stellio during long-term hibernation. We measured levels of the monoamines serotonin (5-HT) and its main metabolite 5-hydroxyindole-3-acetic acid (5-HIAA), dopamine (DA) and its metabolites dihydroxyphenylacetic acid(DOPAC) and homovanilic acid (HVA), norepinephrine (NE) and epinephrine (E). The most abundant amines detected in the brain and heart of active H. lucorum were 5-HT and DA. Of the metabolites examined only 5-HIAA was found in the brain. NE was found at very low levels but only in the brain,while E was not detected in the brain and heart. The levels of 5-HT and 5-HIAA increased in the brain and heart of H. lucorum within the first months of hibernation, showing a significant decrease thereafter. The levels of DA did not change during hibernation. The results indicated that 5-HT might be involved in preparing snails for entry into hibernation. GABA was only found in the brain of H. lucorum, and the levels were low; these levels remained during hibernation. Adenosine was present in brain and heart of H. lucorum, and during hibernation, the level of adenosine decreased significantly in the brain but remained steady in the heart. The monoamines 5-HT, DA and NE were present in the brain of active lizards A. stellio stellio, whereas E was found only at very low levels. Moreover,the metabolites 5-HIAA, DOPAC and HVA were detected in the brain of active lizards. The monoamines 5-HT, DA, NE and E were also detected in the heart and blood of active lizards. During hibernation the levels of these four monoamines were decreased significantly in the brain and heart of A. stellio stellio. In contrast, the levels of E increased in the heart and blood of hibernating lizards. Adenosine was detected in both heart and brain of active lizards, but hibernation caused a marked decrease in its levels at both tissues. GABA was found at higher levels than monoamines and adenosine in the brain of active lizards, and hibernation caused a significant increase in its levels, indicating an important role of GABA in inhibition of neuronal activity in hibernating lizards.

POPDC proteins and cardiac function

2019 ◽  
Vol 47 (5) ◽  
pp. 1393-1404 ◽  
Author(s):  
Thomas Brand
Keyword(s):  
Potential Role ◽  
Striated Muscle ◽  
Short Review ◽  
Effector Proteins ◽  
Muscle Disease ◽  
Disease Genes ◽  
Protein Protein Interaction ◽  
Interaction Partners ◽  
And Function

Abstract The Popeye domain-containing gene family encodes a novel class of cAMP effector proteins in striated muscle tissue. In this short review, we first introduce the protein family and discuss their structure and function with an emphasis on their role in cyclic AMP signalling. Another focus of this review is the recently discovered role of POPDC genes as striated muscle disease genes, which have been associated with cardiac arrhythmia and muscular dystrophy. The pathological phenotypes observed in patients will be compared with phenotypes present in null and knockin mutations in zebrafish and mouse. A number of protein–protein interaction partners have been discovered and the potential role of POPDC proteins to control the subcellular localization and function of these interacting proteins will be discussed. Finally, we outline several areas, where research is urgently needed.

The Effect of Path Length and Display Size on Memory for Spatial Information

2012 ◽  
Vol 59 (3) ◽  
pp. 147-152 ◽  
Author(s):  
Katherine Guérard ◽  
Sébastien Tremblay
Keyword(s):  
Path Length ◽  
Potential Role ◽  
Spatial Information ◽  
Recall Performance ◽  
Minor Role ◽  
Length Effect ◽  
Serial Memory ◽  
Fixed Reference ◽  
A Minor

In serial memory for spatial information, some studies showed that recall performance suffers when the distance between successive locations increases relatively to the size of the display in which they are presented (the path length effect; e.g., Parmentier et al., 2005) but not when distance is increased by enlarging the size of the display (e.g., Smyth & Scholey, 1994). In the present study, we examined the effect of varying the absolute and relative distance between to-be-remembered items on memory for spatial information. We manipulated path length using small (15″) and large (64″) screens within the same design. In two experiments, we showed that distance was disruptive mainly when it is varied relatively to a fixed reference frame, though increasing the size of the display also had a small deleterious effect on recall. The insertion of a retention interval did not influence these effects, suggesting that rehearsal plays a minor role in mediating the effects of distance on serial spatial memory. We discuss the potential role of perceptual organization in light of the pattern of results.

Business Model Literature Overview

2014 ◽  
pp. 79-130 ◽  
Author(s):  
Ales Novak
Keyword(s):  
Business Model ◽  
Financial Reporting ◽  
Business Models ◽  
Potential Role ◽  
Financial Instruments ◽  
Business Logic ◽  
Literature Overview ◽  
Ifrs 9 ◽  
Definition Of

The term ?business model' has recently attracted increased attention in the context of financial reporting and was formally introduced into the IFRS literature when IFRS 9 Financial Instruments was published in November 2009. However, IFRS 9 did not fully define the term ‘business model'. Furthermore, the literature on business models is quite diverse. It has been conducted in largely isolated fashion; therefore, no generally accepted definition of ?business model' has emerged. Therefore, a better understanding of the notion itself should be developed before further investigating its potential role within financial reporting. The aim of this paper is to highlight some of the perceived key themes and to identify other bases for grouping/organizing the literature based on business models. The contributions this paper makes to the literature are twofold: first, it complements previous review papers on business models; second, it contains a clear position on the distinction between the notions of the business model and strategy, which many authors identify as a key element in better explaining and communicating the notion of the business model. In this author's opinion, the term ‘strategy' is a dynamic and forward-looking notion, a sort of directional roadmap for future courses of action, whereas, ‘business model' is a more static notion, reflecting the conceptualisation of the company's underlying core business logic. The conclusion contains the author's thoughts on the role of the business model in financial reporting.

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