1,055 research outputs found
Flavanol-anthocyanin condensed pigments in plant extracts
Pigments resulting from the direct condensation of anthocyanins and flavanols are usually associated with reactions taking place during processing and storage of plant-derived foods and beverages and have been particularly studied in aged red wines. In this paper, small amounts of flavanol-anthocyanin condensed pigments are found in different plant extracts. Structures are suggested for 10 such condensed pigments detected in extracts of strawberry, runner beans, purple corn and grape skins, based on their MS" fragmentation patterns, following analyses by electrospray tandem mass spectrometry. All of them correspond to dimers containing a flavan-3-ol [either (epi)afzelechin, (epi)catechin or (epi)gallocatechin] as the upper unit carbon-carbon linked to a lower anthocyanin unit consisting of different delphinidin, cyanidin, pelargonidin, peonidin or malvidin derivatives. The detection of these pigments in plant extracts may suggest that they are natural pigments and not products exclusively formed during storage and ageing of processed foods and beverages, as was previously assumed.Comissão Europeia (Fundo Social Europeu) e Governo Português através do Programa PRODEP (III) - ref.ª 5.3/N/199.006/00-Doutoramento
The general anaesthetic etomidate inhibits the excitability of mouse thalamocortical relay neurons by modulating multiple modes of GABA<sub>A</sub> receptor-mediated inhibition
Modulation of thalamocortical (TC) relay neuron function has been implicated in the sedative and hypnotic effects of general anaesthetics. Inhibition of TC neurons is mediated predominantly by a combination of phasic and tonic inhibition, together with a recently described ‘spillover’ mode of inhibition, generated by the dynamic recruitment of extrasynaptic γ-aminobutyric acid (GABA)(A) receptors (GABA(A)Rs). Previous studies demonstrated that the intravenous anaesthetic etomidate enhances tonic and phasic inhibition in TC relay neurons, but it is not known how etomidate may influence spillover inhibition. Moreover, it is unclear how etomidate influences the excitability of TC neurons. Thus, to investigate the relative contribution of synaptic (α1β2γ2) and extrasynaptic (α4β2δ) GABA(A)Rs to the thalamic effects of etomidate, we performed whole-cell recordings from mouse TC neurons lacking synaptic (α1(0/0)) or extrasynaptic (δ(0/0)) GABA(A)Rs. Etomidate (3 μm) significantly inhibited action-potential discharge in a manner that was dependent on facilitation of both synaptic and extrasynaptic GABA(A)Rs, although enhanced tonic inhibition was dominant in this respect. Additionally, phasic inhibition evoked by stimulation of the nucleus reticularis exhibited a spillover component mediated by δ-GABA(A)Rs, which was significantly prolonged in the presence of etomidate. Thus, etomidate greatly enhanced the transient suppression of TC spike trains by evoked inhibitory postsynaptic potentials. Collectively, these results suggest that the deactivation of thalamus observed during etomidate-induced anaesthesia involves potentiation of tonic and phasic inhibition, and implicate amplification of spillover inhibition as a novel mechanism to regulate the gating of sensory information through the thalamus during anaesthetic states
Brighton v RSPCA NSW: Appeals and Lessons Four Years On
Animal law has the potential to initiate improvements for animal wellbeing. However, this largely depends on how effectively the law bridges the legal chasm between animal welfare and animal suffering, a chasm the authors refer to as the welfare gap. When the law does not adequately address this gap, where regulation subordinates animal interests to human interests, it results in weak animal protection that does little more than regulate to a standard that avoids a life not worth living. The authors analyse a series of cases involving the RSPCA and Brighton, in which Brighton was charged with serious animal cruelty pursuant to s 530 of the Crimes Act 1900 (NSW). He stabbed a dog with a pitchfork; after failing to kill the dog, he suspended it from a tree branch by a leash attached to its collar and struck the dog several times on the head with a mallet, finally killing him. Brighton was found guilty in the NSW Local Court and appealed to the NSW Supreme Court, where Rothman J allowed the appeal, holding that Brighton had exterminated a pest animal. This led to protracted litigation, including to the NSW Court of Appeal, a second hearing in the Local Court and a further appeal to the Supreme Court. In August 2020, Sophie Riley published a case note and commentary on the litigation up to the Rothman J appeal. This paper evaluates the litigation that followed, identifying how regulatory failures have entrenched the welfare gap. Regulatory failures include inadequate and aged legislative protections for a confined subset of animals. In NSW, animal sentience is not enshrined in legislation; the law limits the types of animals protected by anti-cruelty law; fundamental statutory language remains undefined, for example terms such as “pest animal” and “exterminate”; and challenges abound for adducing sufficient evidence to prove subjective criminal intent. These deficiencies pose significant challenges for practitioners and judicial officers, particularly when complex statutory interpretation is required in the busy and fast-paced summary jurisdiction. This paper concludes that legislators should consider modernising the law, removing ambiguity, and settling minimum standards for a good life for animals, taking into account the welfare aspects described in Mellor’s Five Domains mode
tert-Butyl 6-benzoyl-5-hydroxy-2-oxo-2H-chromene-4-carboxylate
In the title compound, C21H18O6, a previously unknown coumarin derivative, the benzoyl substitutent makes a dihedral angle of 53.80 (16)° with the plane of the coumarin rings. An intramolecular O—H⋯O hydrogen bond is observed
Evaluating the performance of the ‘Seabin’ : a fixed point mechanical litter removal device for sheltered waters
AbstractMechanical interventions are increasingly suggested as a means of removing plastic litter from aquatic environments; their performance is rarely evaluated, but such information is critical to inform policy interventions such as those required to facilitate UNEA 5.2. The Seabin, a fixed-point device designed to remove floating litter in sheltered waters was examined in an urban tidal marina (Southwest UK). It captured on average 58 litter items/day; chiefly plastic pellets, polystyrene balls and plastic fragments. It also captured one marine organism for every 3.6 items of litter, or 13 organisms/day, half of which were dead upon retrieval. The rate of litter capture was inferior to manual cleaning conducted with nets from pontoons or vessels. Hence, in this location the Seabin was of minimal benefit in terms of marine litter removal and resulted in mortality of marine organisms. The presence of such devices could also precipitate false optimism and reliance on technological solutions, rather than systemic changes in our production, use, and disposal of plastics.Abstract
Mechanical interventions are increasingly suggested as a means of removing plastic litter from aquatic environments; their performance is rarely evaluated, but such information is critical to inform policy interventions such as those required to facilitate UNEA 5.2. The Seabin, a fixed-point device designed to remove floating litter in sheltered waters was examined in an urban tidal marina (Southwest UK). It captured on average 58 litter items/day; chiefly plastic pellets, polystyrene balls and plastic fragments. It also captured one marine organism for every 3.6 items of litter, or 13 organisms/day, half of which were dead upon retrieval. The rate of litter capture was inferior to manual cleaning conducted with nets from pontoons or vessels. Hence, in this location the Seabin was of minimal benefit in terms of marine litter removal and resulted in mortality of marine organisms. The presence of such devices could also precipitate false optimism and reliance on technological solutions, rather than systemic changes in our production, use, and disposal of plastics
Molecular modeling of a tandem two pore domain potassium channel reveals a putative binding Site for general anesthetics
[Image: see text] Anesthetics are thought to mediate a portion of their activity via binding to and modulation of potassium channels. In particular, tandem pore potassium channels (K2P) are transmembrane ion channels whose current is modulated by the presence of general anesthetics and whose genetic absence has been shown to confer a level of anesthetic resistance. While the exact molecular structure of all K2P forms remains unknown, significant progress has been made toward understanding their structure and interactions with anesthetics via the methods of molecular modeling, coupled with the recently released higher resolution structures of homologous potassium channels to act as templates. Such models reveal the convergence of amino acid regions that are known to modulate anesthetic activity onto a common three- dimensional cavity that forms a putative anesthetic binding site. The model successfully predicts additional important residues that are also involved in the putative binding site as validated by the results of suggested experimental mutations. Such a model can now be used to further predict other amino acid residues that may be intimately involved in the target-based structure–activity relationships that are necessary for anesthetic binding
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