Taking the beat of the Arctic: are lemming population cycles changing due to winter climate?

Reports of fading vole and lemming population cycles and persisting low populations in some parts of the Arctic have raised concerns about the spread of these fundamental changes to tundra food web dynamics. By compiling 24 unique time series of lemming population fluctuations across the circumpolar region, we show that virtually all populations displayed alternating periods of cyclic/non-cyclic fluctuations over the past four decades. Cyclic patterns were detected 55% of the time (n = 649 years pooled across sites) with a median periodicity of 3.7 years, and non-cyclic periods were not more frequent in recent years. Overall, there was an indication for a negative effect of warm spells occurring during the snow onset period of the preceding year on lemming abundance. However, winter duration or early winter climatic conditions did not differ on average between cyclic and non-cyclic periods. Analysis of the time series shows that there is presently no Arctic-wide collapse of lemming cycles, even though cycles have been sporadic at most sites during the last decades. Although non-stationary dynamics appears a common feature of lemming populations also in the past, continued warming in early winter may decrease the frequency of periodic irruptions with negative consequences for tundra ecosystems.

A circumpolar study unveils a positive non-linear effect of temperature on arctic arthropod availability that may reduce the risk of warming-induced trophic mismatch for breeding shorebirds.

Seasonally abundant arthropods are a crucial food source for many migratory birds that breed in the Arctic. In cold environments, the growth and emergence of arthropods are particularly tied to temperature. Thus, the phenology of arthropods is anticipated to undergo a rapid change in response to a warming climate, potentially leading to a trophic mismatch between migratory insectivorous birds and their prey. Using data from 19 sites spanning a wide temperature gradient from the Subarctic to the High Arctic, we investigated the effects of temperature on the phenology and biomass of arthropods available to shorebirds during their short breeding season at high latitudes. We hypothesized that prolonged exposure to warmer summer temperatures would generate earlier peaks in arthropod biomass, as well as higher peak and seasonal biomass. Across the temperature gradient encompassed by our study sites (>10°C in average summer temperatures), we found a 3-day shift in average peak date for every increment of 80 cumulative thawing degree-days. Interestingly, we found a linear relationship between temperature and arthropod biomass only below temperature thresholds. Higher temperatures were associated with higher peak and seasonal biomass below 106 and 177 cumulative thawing degree-days, respectively, between June 5 and July 15. Beyond these thresholds, no relationship was observed between temperature and arthropod biomass. Our results suggest that prolonged exposure to elevated temperatures can positively influence prey availability for some arctic birds. This positive effect could, in part, stem from changes in arthropod assemblages and may reduce the risk of trophic mismatch.

Why do avian responses to change in Arctic green-up vary?

Global climate change has altered the timing of seasonal events (i.e., phenology) for a diverse range of biota. Within and among species, however, the degree to which alterations in phenology match climate variability differ substantially. To better understand factors driving these differences, we evaluated variation in timing of nesting of eight Arctic-breeding shorebird species at 18 sites over a 23-year period. We used the Normalized Difference Vegetation Index as a proxy to determine the start of spring (SOS) growing season and quantified relationships between SOS and nest initiation dates as a measure of phenological responsiveness. Among species, we tested four life history traits (migration distance, seasonal timing of breeding, female body mass, expected female reproductive effort) as species-level predictors of responsiveness. For one species (Semipalmated Sandpiper), we also evaluated whether responsiveness varied across sites. Although no species in our study completely tracked annual variation in SOS, phenological responses were strongest for Western Sandpipers, Pectoral Sandpipers, and Red Phalaropes. Migration distance was the strongest additional predictor of responsiveness, with longer-distance migrant species generally tracking variation in SOS more closely than species that migrate shorter distances. Semipalmated Sandpipers are a widely distributed species, but adjustments in timing of nesting relative to variability in SOS did not vary across sites, suggesting that different breeding populations of this species were equally responsive to climate cues despite differing migration strategies. Our results unexpectedly show that long-distance migrants are more sensitive to local environmental conditions, which may help them to adapt to ongoing changes in climate.

Astringency and its sub-qualities: a review of astringency mechanisms and methods for measuring saliva lubrication.

Astringency is an important mouthfeel attribute that influences the sensory experiences of many food and beverage products. While salivary lubricity loss and increased oral friction were previously believed to be the only astringency mechanisms, recent research has demonstrated that nontactile oral receptors can trigger astringency by responding to astringents without mechanical stimulation. Various human factors have also been identified that affect individual responses to astringents. This article presents a critical review of the key research milestones contributing to the current understanding of astringency mechanisms and the instrumental approaches used to quantify perceived astringency intensity. Although various chemical assays or physical measures mimic in-mouth processes involved in astringent mouthfeel, this review highlights how one chemical or physical approach can only provide a single measure of astringency determined by a specific mechanism. Subsequently, using a single measurement to predict astringency perception is overly idealistic. Astringency has not been quantified beyond the loss of saliva lubrication; therefore, nontactile receptor-based responses must also be explored. An important question remains about whether astringency is a single perception or involves distinct sub-qualities such as pucker, drying, and roughness. Although these sub-quality lexicons have been frequently cited, most studies currently view astringency as a single perception rather than dividing it into sub-qualities and investigating the potentially independent mechanisms of each. Addressing these knowledge gaps should be an important priority for future research.

Review of terrestrial temporarily conserved areas in Canada, the United States, and Mexico.

The establishment of protected areas is a cornerstone of conservation, but permanent protection could be inefficient or even impossible in some situations. We synthesized the literature on temporarily conserved areas (TCAs) across Canada, the United States, and Mexico. We used a comprehensive search string to retrieve peer-reviewed articles published from 2000 to 2021 from the Web of Science. We identified 27 relevant peer-reviewed articles that examined the potential benefits of TCAs in the study area, indicating TCA is a relatively understudied area of research in the peer-reviewed literature. The TCA studies were highly clustered; 77% of studies focused on protecting a single life stage of migratory species and 61% of studies related to temporary conservation of breeding or staging habitats for migratory birds. Ninety-three percent of studies focused on preventing human-driven threats, mainly on public lands of coastal areas, the Great Plains, and the Mississippi Valley in the central United States. Short-term and experimental studies were the dominant study types. TCAs have the potential to complement permanently protected areas and provide protection when permanent protection is difficult. Some included studies examined their conservation value, but the ecological, social, and economic outcomes of TCAs are unclear. More TCA research is needed to determine the role they could play in conservation worldwide. Embracing the concept of TCAs as conservation tool could lead to more comprehensive and consistent reporting of the outcomes of temporary area-based conservation measures. However, a global review and analysis of effectiveness of TCAs will be required if they are to play a formal role in meeting international targets for biodiversity conservation.

Revisión de áreas terrestres conservadas temporalmente en Canadá, Estados Unidos y México Resumen La creación de áreas protegidas es una piedra angular de la conservación, aunque en algunos casos la protección permanente podría ser ineficiente o incluso imposible. Condensamos la literatura sobre las áreas de conservación temporal (ACT) en Canadá, Estados Unidos y México. Usamos una cadena completa de búsqueda para obtener artículos revisados por pares publicados del 2000 al 2021 en Web of Science. Identificamos 27 artículos relevantes que analizaban el potencial de las ACT en el área de estudio, lo que indica que las ACT es un área poco estudiada en la literatura revisada por pares. Los estudios sobre ACT estaban muy agrupados: el 77% se enfocaban en la protección de un solo estadio de vida de las especies migratorias y el 61% se relacionaban con la conservación temporal de los hábitats de reproducción o de descanso de las aves migratorias. El 93% de los estudios se enfocó en la prevención de amenazas causadas por humanos, principalmente en los terrenos públicos de las áreas costeras, las Grandes Llanuras y el valle del Mississippi en el centro de los Estados Unidos. Los estudios experimentales y a corto plazo fueron el tipo de estudio dominante. Las áreas de conservación temporal tienen el potencial para complementar las áreas de protección permanente y proporcionar protección cuando es complicado proporcionarla permanentemente. Algunos de los estudios incluidos analizaron el valor para la conservación de las ACT, pero aún no están claros sus resultados ecológicos, sociales y económicos. Se necesita más investigación sobre las ACT para determinar el papel que podrían tener en la conservación mundial. Si se acepta el concepto de ACT como una herramienta de conservación, se podrían reportar los resultados de las medidas de conservación basadas en las ACT de forma más completa y consistente. Sin embargo, se requerirá una revisión y análisis global de la eficiencia de las ACT si se espera que tengan un papel formal en el cumplimiento de los objetivos internacionales de la conservación de la biodiversidad.

Factors influencing mercury exposure in Arctic-breeding shorebirds.

Mercury (Hg) pollution remains a concern to Arctic ecosystems, due to long-range transport from southern industrial regions and melting permafrost and glaciers. The objective of this study was to identify intrinsic, extrinsic, and temporal factors influencing Hg concentrations in Arctic-breeding shorebirds and highlight regions and species at greatest risk of Hg exposure. We analyzed 1094 blood and 1384 feather samples from 12 shorebird species breeding at nine sites across the North American Arctic during 2012 and 2013. Blood Hg concentrations, which reflect Hg exposure in the local area in individual shorebirds: 1) ranged from 0.01-3.52 µg/g ww, with an overall mean of 0.30 ± 0.27 µg/g ww; 2) were influenced by species and study site, but not sampling year, with birds sampled near Utqiagvik, AK, having the highest concentrations; and 3) were influenced by foraging habitat at some sites. Feather Hg concentrations, which reflected Hg exposure from the wintering grounds: 1) ranged from 0.07-12.14 µg/g fw in individuals, with an overall mean of 1.14 ± 1.18 µg/g fw; and 2) were influenced by species and year. Most Arctic-breeding shorebirds had blood and feather Hg concentrations at levels where no adverse effects of exposure were predicted, though some individuals sampled near Utqiagvik had Hg levels that would be considered of concern. Overall, these data increase our understanding of how Hg is distributed in the various shorebird breeding areas of the Arctic, what factors predispose Arctic-breeding shorebirds to Hg exposure, and lay the foundation for future monitoring efforts.

Drought at a coastal wetland affects refuelling and migration strategies of shorebirds.

Droughts can affect invertebrate communities in wetlands, which can have bottom-up effects on the condition and survival of top predators. Shorebirds, key predators at coastal wetlands, have experienced widespread population declines and could be negatively affected by droughts. We explored, in detail, the effects of drought on multiple aspects of shorebird stopover and migration ecology by contrasting a year with average wet/dry conditions (2016) with a year with moderate drought (2017) at a major subarctic stopover site on southbound migration. We also examined the effects of drought on shorebird body mass during stopover across 14 years (historical: 1974-1982 and present-day: 2014-2018). For the detailed comparison of two years, in the year with moderate drought we documented lower invertebrate abundance at some sites, higher prey family richness in shorebird faecal samples, lower shorebird refuelling rates, shorter stopover durations for juveniles, and, for most species, a higher probability of making a subsequent stopover in North America after departing the subarctic, compared to the year with average wet/dry conditions. In the 14-year dataset, shorebird body mass tended to be lower in drier years. We show that even short-term, moderate drought conditions can negatively affect shorebird refuelling performance at coastal wetlands, which may carry-over to affect subsequent stopover decisions. Given shorebird population declines and predicted changes in the severity and duration of droughts with climate change, researchers should prioritize a better understanding of how droughts affect shorebird refuelling performance and survival.

Nitric oxide regulates the firing rate of neuronal subtypes in the guinea pig ventral cochlear nucleus.

The gaseous free radical, nitric oxide (NO) acts as a ubiquitous neuromodulator, contributing to synaptic plasticity in a complex way that can involve either long term potentiation or depression. It is produced by neuronal nitric oxide synthase (nNOS) which is presynaptically expressed and also located postsynaptically in the membrane and cytoplasm of a subpopulation of each major neuronal type in the ventral cochlear nucleus (VCN). We have used iontophoresis in vivo to study the effect of the NOS inhibitor L-NAME (L-NG-Nitroarginine methyl ester) and the NO donors SIN-1 (3-Morpholinosydnonimine hydrochloride) and SNOG (S-Nitrosoglutathione) on VCN units under urethane anaesthesia. Collectively, both donors produced increases and decreases in driven and spontaneous firing rates of some neurones. Inhibition of endogenous NO production with L-NAME evoked a consistent increase in driven firing rates in 18% of units without much effect on spontaneous rate. This reduction of gain produced by endogenous NO was mirrored when studying the effect of L-NAME on NMDA(N-Methyl-D-aspartic acid)-evoked excitation, with 30% of units showing enhanced NMDA-evoked excitation during L-NAME application (reduced NO levels). Approximately 25% of neurones contain nNOS and the NO produced can modulate the firing rate of the main principal cells: medium stellates (choppers), large stellates (onset responses) and bushy cells (primary-like responses). The main endogenous role of NO seems to be to partly suppress driven firing rates associated with NMDA channel activity but there is scope for it to increase neural gain if there were a pathological increase in its production following hearing loss.

Flower-visitor communities of an arcto-alpine plant-Global patterns in species richness, phylogenetic diversity and ecological functioning.

Pollination is an ecosystem function of global importance. Yet, who visits the flower of specific plants, how the composition of these visitors varies in space and time and how such variation translates into pollination services are hard to establish. The use of DNA barcodes allows us to address ecological patterns involving thousands of taxa that are difficult to identify. To clarify the regional variation in the visitor community of a widespread flower resource, we compared the composition of the arthropod community visiting species in the genus Dryas (mountain avens, family Rosaceae), throughout Arctic and high-alpine areas. At each of 15 sites, we sampled Dryas visitors with 100 sticky flower mimics and identified specimens to Barcode Index Numbers (BINs) using a partial sequence of the mitochondrial COI gene. As a measure of ecosystem functioning, we quantified variation in the seed set of Dryas. To test for an association between phylogenetic and functional diversity, we characterized the structure of local visitor communities with both taxonomic and phylogenetic descriptors. In total, we detected 1,360 different BINs, dominated by Diptera and Hymenoptera. The richness of visitors at each site appeared to be driven by local temperature and precipitation. Phylogeographic structure seemed reflective of geological history and mirrored trans-Arctic patterns detected in plants. Seed set success varied widely among sites, with little variation attributable to pollinator species richness. This pattern suggests idiosyncratic associations, with function dominated by few and potentially different taxa at each site. Taken together, our findings illustrate the role of post-glacial history in the assembly of flower-visitor communities in the Arctic and offer insights for understanding how diversity translates into ecosystem functioning.

Exposure to a Nonionic Surfactant Induces a Response Akin to Heat-Shock Apoptosis in Intestinal Epithelial Cells: Implications for Excipients Safety.

Amphipathic, nonionic, surfactants are widely used in pharmaceutical, food, and agricultural industry to enhance product features; as pharmaceutical excipients, they are also aimed at increasing cell membrane permeability and consequently improving oral drugs absorption. Here, we report on the concentration- and time-dependent succession of events occurring throughout and subsequent exposure of Caco-2 epithelium to a "typical" nonionic surfactant (Kolliphor HS15) to provide a molecular explanation for nonionic surfactant cytotoxicity. The study shows that the conditions of surfactant exposure, which increase plasma membrane fluidity and permeability, produced rapid (within 5 min) redox and mitochondrial effects. Apoptosis was triggered early during exposure (within 10 min) and relied upon an initial mitochondrial membrane hyperpolarization (5-10 min) as a crucial step, leading to its subsequent depolarization and caspase-3/7 activation (60 min). The apoptotic pathway appears to be triggered prior to substantial surfactant-induced membrane damage (observed ≥60 min). We hence propose that the cellular response to the model nonionic surfactant is triggered via surfactant-induced increase in plasma membrane fluidity, a phenomenon akin to the stress response to membrane fluidization induced by heat shock, and consequent apoptosis. Therefore, the fluidization effect that confers surfactants the ability to enhance drug permeability may also be intrinsically linked to the propagation of their cytotoxicity. The reported observations have important implications for the safety of a multitude of nonionic surfactants used in drug delivery formulations and to other permeability enhancing compounds with similar plasma membrane fluidizing mechanisms.

Changes in Metal Ion Concentrations in a Chardonnay Wine Related to Oxygen Exposure during Vinification.

The impact of oxygen exposure during winemaking on metal ion concentrations in wine were investigated throughout the winemaking process in a Chardonnay wine. The concentrations of Al, Ca, Co, Cr, Cu, Fe, K, Mg, Mn, Na, Ni, Sn, and Zn were determined using inductively coupled plasma-mass spectrometry. Oxygen exposure significantly impacted 13 metal ions at different phases of winemaking. However, only the concentrations of Cr, Cu, and Fe were impacted by early oxygen exposure during pressing, with lower Cr and Cu concentrations in wines that were aerobically pressed and lower concentrations of Fe in wines that were inertly pressed. The sequestering of Al, Cu, Ni, and Zn by wine lees was significantly affected by oxygen treatment, with lees collected from wines that were treated oxidatively sequestering significantly greater amounts of Cu and Zn and removing these metals from the wine supernatant. The metal ion that was most affected by oxygen exposure during pressing and handling was Cu, with significantly lower Cu measured in wines that were produced under oxidative conditions. It is known that elevated Cu concentrations have negative implications for wine aroma and flavour. This study demonstrated that oxygen management during winemaking significantly impacts metal ion concentrations in lees and wine, which may decrease the risk of developing taints and faults.

Potato Protein Fining of Phenolic Compounds in Red Wine: A Study of the Kinetics and the Impact of Wine Matrix Components and Physical Factors.

Producing wines within an acceptable range of astringency is important for quality and consumer acceptance. Astringency can be modified by fining during the winemaking process and the use of vegetable proteins (especially potato proteins) as fining agents has gained increasing interest due to consumers' requirements. The research presented was the first to investigate the effect of a potato protein dose on the kinetics of tannin and phenolic removal compared to gelatin for two unfined Cabernet Sauvignon wines. To further understand the results, the influence of the wine matrix and fining parameters (including pH, ethanol concentration, sugar concentration, temperature, and agitation) were tested according to a fractional 25-1 factorial design on one of the Cabernet Sauvignon wines using potato proteins. The results from the factorial design indicate that potato protein fining was significantly influenced by wine pH, ethanol concentration, fining temperature as well as an interaction (pH × ethanol) but not by sugar content or agitation. Insights into the steps required for the optimisation of fining were gained from the study, revealing that potato protein fining efficiency could be increased by treating wines at higher temperatures (20 °C, rather than the conventional 10-15 °C), and at both a lower pH and/or alcohol concentration.

The mouthfeel of white wine.

White wine mouthfeel which encompasses the tactile, chemosensory and taste attributes of perceived viscosity, astringency, hotness and bitterness is increasingly being recognized as an important component of overall white wine quality. This review summarizes the physiological basis for the perception of white wine mouthfeel and the direct and interactive effects of white wine composition, specifically those of low molecular weight phenolic compounds, polysaccharides, pH, ethanol, glycerol, dissolved carbon dioxide, and peptides. Ethyl alcohol concentration and pH play a direct role in determining most aspects of mouthfeel perception, and provide an overall framework on which the other minor wine components can interact to influence white wine mouthfeel. Phenolic compounds broadly impact on the mouthfeel by contributing to its viscosity, astringency, hotness and bitterness. Their breadth of influence likely results from their structural diversity which would allow them to activate multiple sensory mechanisms involved in mouthfeel perception. Conversely, polysaccharides have a small modulating effect on astringency and hotness perception, and glycerol does not affect perceived viscosity within the narrow concentration range found in white wine. Many of the major sensory attributes that contribute to the overall impression of mouthfeel are elicited by more than one class compound suggesting that different physiological mechanisms may be involved in the construct of mouthfeel percepts.

JAK/STAT inhibitors and other small molecule cytokine antagonists for the treatment of allergic disease.

OBJECTIVE: To provide an overview of janus kinase (JAK), chemoattractant receptor homologous molecule expressed on TH2 cells (CRTH2), and phosphodiesterase 4 (PDE4) inhibitors in allergic disorders. DATA SOURCES: PubMed literature review. STUDY SELECTIONS: Articles included in this review discuss the emerging mechanism of action of small molecule inhibitors and their use in the treatment of atopic dermatitis (AD), asthma, and allergic rhinitis (AR). RESULTS: Allergic diseases represent a spectrum of diseases, including AD, asthma, and AR. For decades, these diseases have been primarily characterized by increased TH2 signaling and downstream inflammation. In recent years, additional research has identified disease phenotypes and subsets of patients with non-Th2 mediated inflammation. The increasing heterogeneity of disease has prompted investigators to move away from wide-ranging treatment approaches with immunosuppressive agents, such as corticosteroids, to consider more targeted immunomodulatory approaches focused on specific pathways. In the past decade, inhibitors that target JAK signaling, PDE4, and CRTH2 have been explored for their potential activity in models of allergic disease and therapeutic benefit in clinical trials. Interestingly, although JAK inhibitors provide an opportunity to interfere with cytokine signaling and could be beneficial in a broad range of allergic diseases, current clinical trials are focused on the treatment of AD. Conversely, both PDE4 and CRTH2 inhibitors have been evaluated in a spectrum of allergic diseases. This review summarizes the varying degrees of success that these small molecules have demonstrated across allergic diseases. CONCLUSION: Emerging therapies currently in development may provide more consistent benefit to patients with allergic diseases by specifically targeting inflammatory pathways important for disease pathogenesis.

Exploiting Compositionally Similar Grape Marc Samples to Achieve Gradients of Condensed Tannin and Fatty Acids for Modulating In Vitro Methanogenesis.

Ruminants produce large amounts of the greenhouse gas, methane, which can be reduced by supplementing feed with products that contain anti-methanogenic compounds, such as the solid winemaking by-product, grape marc. The aim of this study was to exploit compositional differences in grape marc to better understand the roles of condensed tannin and fatty acids in altering methanogenesis in a ruminant system. Grape marc samples varying in tannin extractability, tannin size and subunit composition, and fatty acid or tannin concentrations were selected and incubated in rumen fluid using an in vitro batch fermentation approach with a concentrate-based control. Four distinct experiments were designed to investigate the effects on overall fermentation and methane production. Generally, fatty acid concentration in grape marc was associated with decreased total gas volumes and volatile fatty acid concentration, whereas increased condensed tannin concentration tended to decrease methane percentage. Smaller, extractable tannin was more effective at reducing methane production, without decreasing overall gas production. In conclusion, fatty acids and tannin concentration, and tannin structure in grape marc play a significant role in the anti-methanogenic effect of this by-product when studied in vitro. These results should be considered when developing strategies to reduce methane in ruminants by feeding grape marc.

Body condition explains migratory performance of a long-distance migrant.

Body condition (i.e. relative mass after correcting for structural size) affects the behaviour of migrating birds, but how body condition affects migratory performance, timing and fitness is still largely unknown. Here, we studied the effects of relative body condition on individual departure decisions, wind selectivity, flight speed and timing of migration for a long-distance migratory shorebird, the red knot Calidris canutus rufa. By using automated VHF telemetry on a continental scale, we studied knots' migratory movements with unprecedented temporal resolution over a 3-year period. Knots with a higher relative body condition left the staging site later than birds in lower condition, yet still arrived earlier to their Arctic breeding grounds compared to knots in lower relative body condition. They accomplished this by selecting more favourable winds at departure, thereby flying faster and making shorter stops en route Individuals with a higher relative body condition in spring migrated south up to a month later than individuals in lower condition, suggesting that individuals in better condition were more likely to have bred successfully. Moreover, individuals with a lower relative body condition in spring had a lower probability of being detected in autumn, suggestive of increased mortality. The pressure to arrive early to the breeding grounds is considered to be an important constraint of migratory behaviour and this study highlights the important influence of body condition on migratory decisions, performance and potentially fitness of migrant birds.

Deficiency of MALT1 paracaspase activity results in unbalanced regulatory and effector T and B cell responses leading to multiorgan inflammation.

The paracaspase MALT1 plays an important role in immune receptor-driven signaling pathways leading to NF-κB activation. MALT1 promotes signaling by acting as a scaffold, recruiting downstream signaling proteins, as well as by proteolytic cleavage of multiple substrates. However, the relative contributions of these two different activities to T and B cell function are not well understood. To investigate how MALT1 proteolytic activity contributes to overall immune cell regulation, we generated MALT1 protease-deficient mice (Malt1(PD/PD)) and compared their phenotype with that of MALT1 knockout animals (Malt1(-/-)). Malt1(PD/PD) mice displayed defects in multiple cell types including marginal zone B cells, B1 B cells, IL-10-producing B cells, regulatory T cells, and mature T and B cells. In general, immune defects were more pronounced in Malt1(-/-) animals. Both mouse lines showed abrogated B cell responses upon immunization with T-dependent and T-independent Ags. In vitro, inactivation of MALT1 protease activity caused reduced stimulation-induced T cell proliferation, impaired IL-2 and TNF-α production, as well as defective Th17 differentiation. Consequently, Malt1(PD/PD) mice were protected in a Th17-dependent experimental autoimmune encephalomyelitis model. Surprisingly, Malt1(PD/PD) animals developed a multiorgan inflammatory pathology, characterized by Th1 and Th2/0 responses and enhanced IgG1 and IgE levels, which was delayed by wild-type regulatory T cell reconstitution. We therefore propose that the pathology characterizing Malt1(PD/PD) animals arises from an immune imbalance featuring pathogenic Th1- and Th2/0-skewed effector responses and reduced immunosuppressive compartments. These data uncover a previously unappreciated key function of MALT1 protease activity in immune homeostasis and underline its relevance in human health and disease.

Adsorption of Wine Constituents on Functionalized Surfaces.

The adsorption of macromolecules on solid surfaces is of great importance in the field of nanotechnology, biomaterials, biotechnological, and food processes. In the field of oenology adsorption of wine macromolecules such as polyphenols, polysaccharides, and proteins is much less desirable on membrane materials because of fouling and reduced filtering performance. On the other hand, adsorption of these molecules on processing aids is very beneficial for achieving wine clarity and stability. In this article, the effect of surface chemical functionalities on the adsorption of white, rosé, and red wine constituents was evaluated. Allylamine, acrylic acid, and ethanol were selected as precursors for plasma polymerization in order to generate coatings rich in amine, carboxyl, and hydroxyl chemical groups, respectively. The surface chemical functionalities were characterized by X-ray photoelectron spectroscopy (XPS) and the ability of different surface chemical functionalities to adsorb wine constituents were characterized by quartz crystal microbalance with dissipation (QCM-D) and atomic force microscopy (AFM). The results demonstrated that the amine and carboxyl modified surfaces encourage adsorption of constituents from white wine. The hydroxyl modified surfaces have the ability to preferentially adsorb rosé wine constituents, whereas red wine adsorbed to the highest extent on acrylic acid surface.

Formation of Hydrogen Sulfide in Wine: Interactions between Copper and Sulfur Dioxide.

The combined synergistic effects of copper (Cu(2+)) and sulfur dioxide (SO2) on the formation of hydrogen sulfide (H2S) in Verdelho and Shiraz wine samples post-bottling was studied over a 12-month period. The combined treatment of Cu(2+) and SO2 significantly increased H2S formation in Verdelho wines samples that were not previously treated with either Cu(2+) or SO2. The formation of H2S produced through Cu(2+) mediated reactions was likely either: (a) directly through the interaction of SO2 with either Cu(2+) or H2S; or (b) indirectly through the interaction of SO2 with other wine matrix compounds. To gain better understanding of the mechanisms responsible for the significant increases in H2S concentration in the Verdelho samples, the interaction between Cu(2+) and SO2 was studied in a model wine matrix with and without the presence of a representative thiol quenching compound (4-methylbenzoquinone, 4MBQ). In these model studies, the importance of naturally occurring wine compounds and wine additives, such as quinones, SO2, and metal ions, in modulating the formation of H2S post-bottling was demonstrated. When present in equimolar concentrations a 1:1 ratio of H2S- and SO2-catechol adducts were produced. At wine relevant concentrations, however, only SO2-adducts were produced, reinforcing that the competition reactions of sulfur nucleophiles, such as H2S and SO2, with wine matrix compounds play a critical role in modulating final H2S concentrations in wines.

Bioenergetic disruption of human micro-vascular endothelial cells by antipsychotics.

Antipsychotics (APs) are widely used medications, however these are not without side effects such as disruption of blood brain barrier function (BBB). To investigate this further we have studied the chronic effects of the typical APs, chlorpromazine (CPZ) and haloperidol (HAL) and the atypical APs, risperidone (RIS) and clozapine (CLZ), on the bioenergetics of human micro-vascular endothelial cells (HBVECs) of the BBB. Alamar blue (AB) and ATP assays showed that these APs impair bioenergenesis in HBVECs in a concentration and time dependent manner. However since these effects were incomplete they suggest a population of cell bioenergetically heterogeneous, an idea supported by the bistable nature by which APs affected the mitochondrial transmembrane potential. CPZ, HAL and CLZ inhibited the activity of mitochondrial complexes I and III. Our data demonstrates that at therapeutic concentrations, APs can impair the bioenergetic status of HBVECs, an action that help explains the adverse side effects of these drugs when used clinically.