Is there evidence for non-conscious processing in working memory?

Working Memory can be conceived as a mental workspace holding and manipulating a limited amount of recently acquired information for a limited time. Some theories assume that it is tightly coupled with Consciousness (e.g., Baars & Franklin, 2003), commonly defined in experimental studies as the ability to report the content of perception or of memory. Other theories posit that working memory includes cognitive processes of which participants are not conscious (e.g., Soto et al., 2011; Logie, 2016), and can be activated without conscious intention (Hassin et al., 2009). Here, I describe experimental work designed to investigate the possible implicit activation of working memory without awareness. Importantly, participants were not only unaware of the stimuli that might be held in working memory, but also unaware that such stimuli were being presented at all. They were asked to guess which one of four cards presented on the screen was the winning one; one card was subliminally primed before a retention interval (which could vary between 500, 1000, 2000 and 5000 ms). The winner, on each trial, was chosen from amongst four blue cards, one of which had been primed, without awareness, by a card of a different colour (red or green) using Continuous Flash Suppression or Backward Masking. Bayesian and classical analyses from nine experiments mostly support the null hypothesis, thus indicating that working memory was not engaged in performing this task. Two conceptual replications and four exact replications of the original study by Soto et al. (2011), also failed in reproducing the original results. In conclusion, this collection of fifteen experiments encompassing different manipulations shows the absence of non-conscious WM retention, questioning the generalisability of previous studies showing non-conscious WM

Marine pharmacology in 2009-2011: marine compounds with antibacterial, antidiabetic, antifungal, anti-inflammatory, antiprotozoal, antituberculosis, and antiviral activities; affecting the immune and nervous systems, and other miscellaneous mechanisms of action.

The peer-reviewed marine pharmacology literature from 2009 to 2011 is presented in this review, following the format used in the 1998–2008 reviews of this series. The pharmacology of structurally-characterized compounds isolated from marine animals, algae, fungi and bacteria is discussed in a comprehensive manner. Antibacterial, antifungal, antiprotozoal, antituberculosis, and antiviral pharmacological activities were reported for 102 marine natural products. Additionally, 60 marine compounds were observed to affect the immune and nervous system as well as possess antidiabetic and anti-inflammatory effects. Finally, 68 marine metabolites were shown to interact with a variety of receptors and molecular targets, and thus will probably contribute to multiple pharmacological classes upon further mechanism of action studies. Marine pharmacology during 2009–2011 remained a global enterprise, with researchers from 35 countries, and the United States, contributing to the preclinical pharmacology of 262 marine compounds which are part of the preclinical pharmaceutical pipeline. Continued pharmacological research with marine natural products will contribute to enhance the marine pharmaceutical clinical pipeline, which in 2013 consisted of 17 marine natural products, analogs or derivatives targeting a limited number of disease categories

Minor Phytocannabinoids: A Misleading Name but a Promising Opportunity for Biomedical Research

Despite the very large number of phytocannabinoids isolated from Cannabis (Cannabis sativa L.), bioactivity studies have long remained focused on the so called "Big Four" [Δ9-THC (1), CBD (2), CBG (3) and CBC (4)] because of their earlier characterization and relatively easy availability via isolation and/or synthesis. Bioactivity information on the chemical space associated with the remaining part of the cannabinome, a set of ca 150 compounds traditionally referred to as "minor phytocannabinoids", is scarce and patchy, yet promising in terms of pharmacological potential. According to their advancement stage, we sorted the bioactivity data available on these compounds, better referred to as the "dark cannabinome", into categories: discovery (in vitro phenotypical and biochemical assays), preclinical (animal models), and clinical. Strategies to overcome the availability issues associated with minor phytocannabinoids are discussed, as well as the still unmet challenges facing their development as mainstream drugs

Regiodivergent Synthesis of <i>ortho</i>- and <i>para</i>-Cannabinoquinones

Spurred by the remarkable biological profile of cannabinoquinoids, we have systematically investigated the periodinane oxidation of their resorcinolic precursors, discovering that the regiochemistry of oxidation, a critical maneuver for bioactivity, depends not only on the nature of the oxidant (\u3bb3- vs. \u3bb5-iodanes), but also on post-oxidative prototropic- and valence tautomeric equilibria that isomerize ortho-quinones to para-quinones. By complementary selection of the periodinane oxidant and by freezing prototropic equilibration with O-methylation, isomeric ortho- and para-quinones could be obtained from mono- and diphenolic cannabinoids, setting the stage for the exploration of novel areas of the biological space, and establishing a blueprint for the extension of this strategy to other classes of bioactive alkylresorcinols

Triterpenoids from vitellaria paradoxa stem barks reduce nitrite levels in lps-stimulated macrophages

open7siVitellaria paradoxa C. F. Gaertn is widely used in African traditional medicine as an anti-inflammatory remedy to treat rheumatism, gastric problems, diarrhea, and dysentery. The phyto-chemical investigation of the ethyl acetate extract of V. paradoxa stem bark collected in Burkina Faso led to the isolation of eight known and two triterpenes undescribed to date (7 and 10), in the free alcohol form or as acetyl and cinnamyl ester derivatives. The stereostructures of the new compounds were elucidated using HR-ESIMS and 1D and 2D NMR data. The isolated compounds were evaluated in vitro for their inhibitory effect on nitrite levels on murine macrophages J774 stimulated with the lipopolysaccharide (LPS). Among all the compounds tested, lupeol cinnamate (3) and betulinic acid (5) showed a beneficial effect in reducing nitrite levels produced after LPS stimulation.openSirignano C.; Nadembega P.; Poli F.; Romano B.; Lucariello G.; Rigano D.; Taglialatela-Scafati O.Sirignano C.; Nadembega P.; Poli F.; Romano B.; Lucariello G.; Rigano D.; Taglialatela-Scafati O

Antiplasmodial triterpenoids from the fruits of neem, Azadirachta indica.

J Nat Prod. 2010 Aug 27;73(8):1448-52. Antiplasmodial triterpenoids from the fruits of neem, Azadirachta indica. Chianese G, Yerbanga SR, Lucantoni L, Habluetzel A, Basilico N, Taramelli D, Fattorusso E, Taglialatela-Scafati O. Abstract Eight known and two new triterpenoid derivatives, neemfruitins A (9) and B (10), have been isolated from the fruits of neem, Azadirachta indica, a traditional antimalarial plant used by Asian and African populations. In vitro antiplasmodial tests evidenced a significant activity of the known gedunin and azadirone and the new neemfruitin A and provided useful information about the structure-antimalarial activity relationships in the limonoid class