Differential placental ceramide levels during gestational diabetes mellitus (GDM).

BACKGROUND: Gestational diabetes mellitus (GDM) is associated with important factors that influence fetal development. Sphingolipids are known to be associated with the development of diabetes. Our objective was to examine ceramide, a key sphingolipid, hyperosmolarity, and apoptosis in placentas from GDM patients treated with insulin or diet. METHODS: Ceramide levels were assessed in placental tissues using immunohistochemistry. Immunoblot was performed to quantify serine palmitoyltransferase (SPT), the rate-limiting enzyme in ceramide biosynthesis, NFAT5, SMIT, AR, caspase 3 and the X-linked inhibitor of apoptosis. Trophoblast cells were treated with insulin or ceramide and assessments for mitochondrial respiration, caspase 3 and XIAP were also performed. RESULTS: Immunohistochemistry showed increased ceramides in the placental villous trophoblasts of the insulin-treated GDM patients. Nuclear SPT was upregulated only in the insulin-treated GDM placenta when compared to controls. Nuclear NFAT5 was also increased in the GDM placenta. Active caspase 3 was elevated in placentas from both insulin- and diet-treated GDM patients. Mitochondrial respiration was decreased in trophoblasts treated with ceramide. Active caspase was not changed while XIAP protein was increased in trophoblasts treated with ceramide. CONCLUSIONS: Our findings confirm the presence of ceramide in the human placenta of control and GDM patients. Furthermore, we conclude that ceramide is increased in the placental trophoblast during insulin treatment and that its upregulation correlates with elevated NFAT5, SMIT, increased apoptosis and decreased trophoblast mitochondrial respiration.

Cultivation and characterization of the bacterial assemblage of epsomic Basque Lake, BC.

Athalassohaline waters that are rich in divalent ions are good analogues for the chemical environments of Mars and the ocean worlds. Sulfate salts, along with chlorides, are important in Mars regolith with Ca, Fe, Mg, and Na counterions. Certain lakes in the Pacific Northwest are saturated with MgSO4 as epsomite. Here we report on the microbial community of Basque Lake, BC, a group of playas that is saturated with MgSO4. More than 60 bacterial isolates were obtained from Basque Lake soils by enrichment culture and repetitive streak-plating using media containing 10% (~ 1.7 M) NaCl or 50% (~ 2 M) MgSO4. Most of the isolates (~ 75%) were Gram-positive, motile, and produced endospores. Isolates related to Marinococcus halophilus and Virgibacillus marismortui dominated the collection. Halomonas and Salinivibrio were Gram-negative genera found at Basque Lake. Nearly all of the Basque Lake isolates grew at 50% MgSO4, with 65% growing at 60% MgSO4. Several isolates could grow in saturated (67%) MgSO4 (aw = 0.90). All of the isolates grew at 10% NaCl with 70% growing at 20% salinity (~ 3.5 M NaCl; aw = 0.82). Basque Lake isolates grew better at basic pH than acidic pH, with 80% growing at pH 9 and 30% growing at pH 10. Only 20% of the isolates grew at pH 5. Numerical taxonomy dendrograms based on 44 phenetic characteristics showed a strong correspondence to phylogenetic trees constructed from 16S rRNA gene sequences. Pyrosequencing of 16S rRNA gene sequences from direct DNA extracts of Basque Lake soils recovered predominantly Proteobacteria (60%), Firmicutes (11%), and unclassified bacteria (27%). Microbes capable of growth under the extreme chemical conditions of Mars are a particular concern for forward planetary protection should they contaminate a spacecraft.

Prevalence of sucretolerant bacteria in common soils and their isolation and characterization.

Sucretolerant microbes grow in the presence of sugar concentrations high enough to substantially lower water activities. Natural habitats high in sugars are mainly limited to dried fruit, floral nectar, honey, sugarcane, and associated soils. Organisms that tolerate extremes of solute concentration, high enough to lower water activities, might not be expected in common oligoosmotic soils. We report on the isolation of sucretolerant bacteria from common soils using media supplemented with 50% sucrose (a w 0.91) and their physiological characterization and identification by 16S rRNA gene phylogeny. Fifteen of these sucretolerant isolates from common soils were related to four Bacillus spp. A Lysinibacillus and a Microbacterium (actinomycete) also were collected. All grew at 50% sucrose and 13 grew at 60% sucrose. Most probable number counts were used to determine the abundance of sucretolerant microbes in several common soil types, including agricultural, managed turf, and native prairie. Microbial abundance (with fungicides) was about 105 and 103 cells g-1 soil in media containing 50 or 70% sucrose, respectively. The abundances of sucretolerant bacteria in common soils mirror those of halotolerant bacteria that grow at 10 and 20% NaCl. However, there is not a correlation between halotolerance and sucretolerance in our isolates, nor can predictions be made based on taxonomy. Specific solute effects may be at work, rather than biological responses to a single physicochemical parameter such as a w. The occurrence of spore-forming sucretolerant bacteria in common soils has relevance to forward planetary protection and astrobiology. Extraterrestrial habitable regions are defined in part by tolerance to high solute concentrations and osmotolerant soil microbes may contaminate spacecraft.

The utility of whole-genome sequencing to identify likely transmission pairs for pathogens with slow and variable evolution.

Pathogen whole-genome sequencing (WGS) has been used to track the transmission of infectious diseases in extraordinary detail, especially for pathogens that undergo fast and steady evolution, as is the case with many RNA viruses. However, for other pathogens evolution is less predictable, making interpretation of these data to inform our understanding of their epidemiology more challenging and the value of densely collected pathogen genome data uncertain. Here, we assess the utility of WGS for one such pathogen, in the "who-infected-whom" identification problem. We study samples from hosts (130 cattle, 111 badgers) with confirmed infection of M. bovis (causing bovine Tuberculosis), which has an estimated clock rate as slow as ∼0.1-1 variations per year. For each potential pathway between hosts, we calculate the relative likelihood that such a transmission event occurred. This is informed by an epidemiological model of transmission, and host life history data. By including WGS data, we shrink the number of plausible pathways significantly, relative to those deemed likely on the basis of life history data alone. Despite our uncertainty relating to the evolution of M. bovis, the WGS data are therefore a valuable adjunct to epidemiological investigations, especially for wildlife species whose life history data are sparse.

De novo truncating mutations in E6-AP ubiquitin-protein ligase gene (UBE3A) in Angelman syndrome.

Angelman syndrome (AS) is associated with maternal deletions of human chromosome 15q11-q13 and with paternal uniparental disomy for this region indicating that deficiency of an imprinted, maternally expressed gene within the critical interval is the likely cause of the syndrome. Although the gene for E6-AP ubiquitin-protein ligase (UBE3A) was mapped to the critical region for AS, evidence of expression from both parental alleles initially suggested that it was an unlikely candidate gene for this disorder. Because attempts to identify any novel maternally expressed transcripts were unsuccessful and because the UBE3A gene remained within a narrowed AS critical region, we searched for mutations in UBE3A in 11 AS patients without known molecular defects (large deletion, uniparental disomy, or imprinting mutation). This analysis tested the possibility that deficiency of an undefined, maternally expressed transcript or isoform of the UBE3A gene could cause AS. Four mutations were identified including a de novo frameshift mutation and a de novo nonsense mutation in exon 3 and two missense mutations of less certain significance. The de novo truncating mutations indicate that UBE3A is the AS gene and suggest the possibility of a maternally expressed gene product in addition to the biallelically expressed transcript. Intragenic mutation of UBE3A in AS is the first example of a genetic disorder of the ubiquitin-dependent proteolytic pathway in mammals. It may represent an example of a human genetic disorder associated with a locus producing functionally distinct imprinted and biallelically expressed gene products.

Bacterial Growth in Brines Formed by the Deliquescence of Salts Relevant to Cold Arid Worlds.

Hygroscopic salts at Mars' near-surface (MgSO4, (per)chlorates, NaCl) may form brines by absorbing moisture from the atmosphere at certain times through the process of deliquescence. We have previously shown strong bacterial growth in saturated MgSO4 (∼67% w/v as epsomite) at room temperature, and growth was observed at the MgSO4 eutectic point (43% w/v at -4°C). Here, we have investigated the growth of salinotolerant microbes (Halomonas, Marinococcus, Planococcus) from Hot Lake, Washington; Basque Lake, British Columbia; and Great Salt Plains, Oklahoma under deliquescing conditions. Bacterial cultures were grown to mid-log phase in SP medium supplemented with 50% MgSO4 (as epsomite), 20% NaClO3, or 10% NaCl (w/v), and small aliquots in cups were dried by vacuum desiccation. When the dried culture was rehydrated by the manual addition of water, the culture resumed growth in the reconstituted brine. When desiccated cultures were maintained in a sealed container with a brine reservoir of the matching growth medium controlling the humidity of the headspace, the desiccated microbial culture evaporites formed brine by deliquescence using humidity alone. Bacterial cultures resumed growth in all three salts once rehydrated by deliquescence. Cultures of Halomonas sp. str. HL12 showed robust survival and growth when subjected to several cycles of desiccation and deliquescent or manual rehydration. Our laboratory demonstrations of microbial growth in deliquescent brines are relevant to the surface and near-subsurface of cold arid worlds like Mars. When conditions become wetter, hygroscopic evaporite minerals can deliquesce to produce the earliest habitable brines. Survival after desiccation and growth in deliquescent brines increases the likelihood that microbes from Earth, carried on spacecraft, pose a contamination risk to Mars.

Alteration history of Séítah formation rocks inferred by PIXL x-ray fluorescence, x-ray diffraction, and multispectral imaging on Mars.

Collocated crystal sizes and mineral identities are critical for interpreting textural relationships in rocks and testing geological hypotheses, but it has been previously impossible to unambiguously constrain these properties using in situ instruments on Mars rovers. Here, we demonstrate that diffracted and fluoresced x-rays detected by the PIXL instrument (an x-ray fluorescence microscope on the Perseverance rover) provide information about the presence or absence of coherent crystalline domains in various minerals. X-ray analysis and multispectral imaging of rocks from the Séítah formation on the floor of Jezero crater shows that they were emplaced as coarsely crystalline igneous phases. Olivine grains were then partially dissolved and filled by finely crystalline or amorphous secondary silicate, carbonate, sulfate, and chloride/oxychlorine minerals. These results support the hypothesis that Séítah formation rocks represent olivine cumulates altered by fluids far from chemical equilibrium at low water-rock ratios.

Assessing the Sampleability of Bennu's Surface for the OSIRIS-REx Asteroid Sample Return Mission.

NASA's first asteroid sample return mission, OSIRIS-REx, collected a sample from the surface of near-Earth asteroid Bennu in October 2020 and will deliver it to Earth in September 2023. Selecting a sample collection site on Bennu's surface was challenging due to the surprising lack of large ponded deposits of regolith particles exclusively fine enough ( ≤ 2 cm diameter) to be ingested by the spacecraft's Touch-and-Go Sample Acquisition Mechanism (TAGSAM). Here we describe the Sampleability Map of Bennu, which was constructed to aid in the selection of candidate sampling sites and to estimate the probability of collecting sufficient sample. "Sampleability" is a numeric score that expresses the compatibility of a given area's surface properties with the sampling mechanism. The algorithm that determines sampleability is a best fit functional form to an extensive suite of laboratory testing outcomes tracking the TAGSAM performance as a function of four observable properties of the target asteroid. The algorithm and testing were designed to measure and subsequently predict TAGSAM collection amounts as a function of the minimum particle size, maximum particle size, particle size frequency distribution, and the tilt of the TAGSAM head off the surface. The sampleability algorithm operated at two general scales, consistent with the resolution and coverage of data collected during the mission. The first scale was global and evaluated nearly the full surface. Due to Bennu's unexpected boulder coverage and lack of ponded regolith deposits, the global sampleability efforts relied heavily on additional strategies to find and characterize regions of interest based on quantifying and avoiding areas heavily covered by material too large to be collected. The second scale was site-specific and used higher-resolution data to predict collected mass at a given contact location. The rigorous sampleability assessments gave the mission confidence to select the best possible sample collection site and directly enabled successful collection of hundreds of grams of material.

Water alteration of rocks and soils on Mars at the Spirit rover site in Gusev crater.

Gusev crater was selected as the landing site for the Spirit rover because of the possibility that it once held a lake. Thus one of the rover's tasks was to search for evidence of lake sediments. However, the plains at the landing site were found to be covered by a regolith composed of olivine-rich basaltic rock and windblown 'global' dust. The analyses of three rock interiors exposed by the rock abrasion tool showed that they are similar to one another, consistent with having originated from a common lava flow. Here we report the investigation of soils, rock coatings and rock interiors by the Spirit rover from sol (martian day) 1 to sol 156, from its landing site to the base of the Columbia hills. The physical and chemical characteristics of the materials analysed provide evidence for limited but unequivocal interaction between water and the volcanic rocks of the Gusev plains. This evidence includes the softness of rock interiors that contain anomalously high concentrations of sulphur, chlorine and bromine relative to terrestrial basalts and martian meteorites; sulphur, chlorine and ferric iron enrichments in multilayer coatings on the light-toned rock Mazatzal; high bromine concentration in filled vugs and veins within the plains basalts; positive correlations between magnesium, sulphur and other salt components in trench soils; and decoupling of sulphur, chlorine and bromine concentrations in trench soils compared to Gusev surface soils, indicating chemical mobility and separation.

A soft solid surface on Titan as revealed by the Huygens Surface Science Package.

The surface of Saturn's largest satellite--Titan--is largely obscured by an optically thick atmospheric haze, and so its nature has been the subject of considerable speculation and discussion. The Huygens probe entered Titan's atmosphere on 14 January 2005 and descended to the surface using a parachute system. Here we report measurements made just above and on the surface of Titan by the Huygens Surface Science Package. Acoustic sounding over the last 90 m above the surface reveals a relatively smooth, but not completely flat, surface surrounding the landing site. Penetrometry and accelerometry measurements during the probe impact event reveal that the surface was neither hard (like solid ice) nor very compressible (like a blanket of fluffy aerosol); rather, the Huygens probe landed on a relatively soft solid surface whose properties are analogous to wet clay, lightly packed snow and wet or dry sand. The probe settled gradually by a few millimetres after landing.

An integrated view of the chemistry and mineralogy of martian soils.

The mineralogical and elemental compositions of the martian soil are indicators of chemical and physical weathering processes. Using data from the Mars Exploration Rovers, we show that bright dust deposits on opposite sides of the planet are part of a global unit and not dominated by the composition of local rocks. Dark soil deposits at both sites have similar basaltic mineralogies, and could reflect either a global component or the general similarity in the compositions of the rocks from which they were derived. Increased levels of bromine are consistent with mobilization of soluble salts by thin films of liquid water, but the presence of olivine in analysed soil samples indicates that the extent of aqueous alteration of soils has been limited. Nickel abundances are enhanced at the immediate surface and indicate that the upper few millimetres of soil could contain up to one per cent meteoritic material.

An audit of UK audiological practice in specialist paediatric oncology centres regarding hearing assessment of children at risk of ototoxicity due to chemotherapy.

OBJECTIVE: Platinum-based chemotherapy drugs are associated with substantial ototoxicity. The hearing of children treated with these drugs should be closely monitored. METHOD: A questionnaire was sent out to the 19 audiology departments associated with national paediatric cancer specialist centres in the UK looking at current practice in ototoxicity monitoring. RESULTS: Responses were received from 17 of 19 centres (89 per cent). All offered some form of audiometric monitoring service. Extended high-frequency testing (9-20 kHz) was only utilised by 7 services (29 per cent). A majority of respondents were reluctant to consider self-test devices in paediatric ototoxicity monitoring (n = 9; 53 per cent). Provision of long-term audiological follow up is sporadic with only 4 (23 per cent) respondents keeping all children with normal hearing under review once treatment is completed. CONCLUSION: While some good practice in paediatric ototoxicity was identified, opportunities exist to improve clinical practice and protocols, promote multidisciplinary team working and to utilise technologies such as extended high frequency and self-test audiometry.

Origin of Life on Mars: Suitability and Opportunities.

Although the habitability of early Mars is now well established, its suitability for conditions favorable to an independent origin of life (OoL) has been less certain. With continued exploration, evidence has mounted for a widespread diversity of physical and chemical conditions on Mars that mimic those variously hypothesized as settings in which life first arose on Earth. Mars has also provided water, energy sources, CHNOPS elements, critical catalytic transition metal elements, as well as B, Mg, Ca, Na and K, all of which are elements associated with life as we know it. With its highly favorable sulfur abundance and land/ocean ratio, early wet Mars remains a prime candidate for its own OoL, in many respects superior to Earth. The relatively well-preserved ancient surface of planet Mars helps inform the range of possible analogous conditions during the now-obliterated history of early Earth. Continued exploration of Mars also contributes to the understanding of the opportunities for settings enabling an OoL on exoplanets. Favoring geochemical sediment samples for eventual return to Earth will enhance assessments of the likelihood of a Martian OoL.

Increased levels of peroxisome proliferator-activated receptor gamma, coactivator 1 alpha (PGC-1alpha) improve lipid utilisation, insulin signalling and glucose transport in skeletal muscle of lean and insulin-resistant obese Zucker rats.

AIMS/HYPOTHESIS: Reductions in peroxisome proliferator-activated receptor gamma, coactivator 1 alpha (PGC-1alpha) levels have been associated with the skeletal muscle insulin resistance. However, in vivo, the therapeutic potential of PGC-1alpha has met with failure, as supra-physiological overexpression of PGC-1alpha induced insulin resistance, due to fatty acid translocase (FAT)-mediated lipid accumulation. Based on physiological and metabolic considerations, we hypothesised that a modest increase in PGC-1alpha levels would limit FAT upregulation and improve lipid metabolism and insulin sensitivity, although these effects may differ in lean and insulin-resistant muscle. METHODS: Pgc-1alpha was transfected into lean and obese Zucker rat muscles. Two weeks later we examined mitochondrial biogenesis, intramuscular lipids (triacylglycerol, diacylglycerol, ceramide), GLUT4 and FAT levels, insulin-stimulated glucose transport and signalling protein phosphorylation (thymoma viral proto-oncogene 2 [Akt2], Akt substrate of 160 kDa [AS160]), and fatty acid oxidation in subsarcolemmal and intermyofibrillar mitochondria. RESULTS: Electrotransfection yielded physiologically relevant increases in Pgc-1alpha (also known as Ppargc1a) mRNA and protein ( approximately 25%) in lean and obese muscle. This induced mitochondrial biogenesis, and increased FAT and GLUT4 levels, insulin-stimulated glucose transport, and Akt2 and AS160 phosphorylation in lean and obese animals, while bioactive intramuscular lipids were only reduced in obese muscle. Concurrently, PGC-1alpha increased palmitate oxidation in subsarcolemmal, but not in intermyofibrillar mitochondria, in both groups. In obese compared with lean animals, the PGC-1alpha-induced improvement in insulin-stimulated glucose transport was smaller, but intramuscular lipid reduction was greater. CONCLUSIONS/INTERPRETATIONS: Increases in PGC-1alpha levels, similar to those that can be induced by physiological stimuli, altered intramuscular lipids and improved fatty acid oxidation, insulin signalling and insulin-stimulated glucose transport, albeit to different extents in lean and insulin-resistant muscle. These positive effects are probably attributable to limiting the PGC-1alpha-induced increase in FAT, thereby preventing bioactive lipid accumulation as has occurred in transgenic PGC-1alpha animals.

Biological and antigenic similarities of murine interferon-gamma and macrophage-activating factor.

Murine peritoneal exudate cells (PEC) treated with murine recombinant interferon-gamma (IFN-gamma) (greater than 99% estimated purity), or concanavalin A-stimulated spleen cell supernatants developed tumoricidal properties (macrophage activation factor [MAF] activity). MAF activity was found to occur with treatments of 10 U/ml IFN-gamma, and at levels as low as 1 U/ml IFN-gamma if a second signal (5 ng/ml endotoxin) was present in the MAF assay. Endotoxin (lipopolysaccharide [LPS]) alone at these levels failed to induce MAF; induction of MAF was observed at 1,000-fold greater levels. The ability of IFN-gamma to stimulate murine PEC was species specific. Various sources of materials that displayed MAF activity, including supernatants from interleukin 2-dependent cloned cytotoxic murine T lymphocyte lines that did not display detectable antiviral activity, were neutralized by antibody raised and affinity purified against recombinant IFN-gamma. Thus, IFN-gamma, although never detectable by antiviral assays, appears to be present in many lymphokine preparations and has potent macrophage activation capability.

Evaluating a web-based test results system at an urban STI clinic.

BACKGROUND: Notifying patients of gonorrhea and chlamydia test results using online services may improve clinic efficiency and increase receipt of test results. This study evaluated the implementation of an online results system in an urban sexually transmitted infections clinic. METHODS: Using the clinic's electronic medical records system to assess if and how gonorrhea and chlamydia test results were obtained, 3 time periods were examined between December 2007 and April 2009: period 1, six months before initiation of the online results system; Period 2, six months when patients could opt in for online results by creating their own access codes; and Period 3, four months when access codes were assigned. In addition, a survey was conducted to assess reasons for accepting or declining the online results system. RESULTS: A total of 9056 new patient visits were evaluated. During periods 1, 2, and 3, respectively 67%, 67%, and 70% patients received results either online or by telephone (NS). The proportion of patients calling the clinic for results decreased from 67% in period 1, to 51% in period 2, and 36% in period 3 (P < 0.0001). Survey results indicated that patients accepted online results primarily because of the ability to check results anytime of day. Reasons for not accepting results online included lack of Internet access or a preference to receive results via the telephone. CONCLUSIONS: The online results system decreased the number of phone calls to the clinic pertaining to STI test results, but had no effect on the overall proportion of patients receiving results.

Macrobiont: Cradle for the Origin of Life and Creation of a Biosphere.

Although the cellular microorganism is the fundamental unit of biology, the origin of life (OoL) itself is unlikely to have occurred in a microscale environment. The macrobiont (MB) is the macro-scale setting where life originated. Guided by the methodologies of Systems Analysis, we focus on subaerial ponds of scale 3 to 300 m diameter. Within such ponds, there can be substantial heterogeneity, on the vertical, horizontal, and temporal scales, which enable multi-pot prebiotic chemical evolution. Pond size-sensitivities for several figures of merit are mathematically formulated, leading to the expectation that the optimum pond size for the OoL is intermediate, but biased toward smaller sizes. Sensitivities include relative access to nutrients, energy sources, and catalysts, as sourced from geological, atmospheric, hydrospheric, and astronomical contributors. Foreshores, especially with mudcracks, are identified as a favorable component for the success of the macrobiont. To bridge the gap between inanimate matter and a planetary-scale biosphere, five stages of evolution within the macrobiont are hypothesized: prebiotic chemistry → molecular replicator → protocell → macrobiont cell → colonizer cell. Comparison of ponds with other macrobionts, including hydrothermal and meteorite settings, allows a conclusion that more than one possible macrobiont locale could enable an OoL.

Isolation and characterization of an endogenous type C virus of rhesus monkeys.

A type C retrovirus was isolated from a continuous cell line established from a spontaneous esophageal carcinoma of a rhesus monkey (Macaca mulata) by prolonged cocultivation with canine cells. A DNA transcript of the viral RNA hybridized to a high level and kinetic analysis indicated the presence of multiple copies of the viral genome in rhesus monkey DNA, showing that the virus is endogenous in this species. The rhesus monkey virus closely resembles, in several respects, an endogenous type C virus previously isolated from stumptailed macques (Macaca arctoides), aa species closely related to rhesus monkeys.

Effects of acute alcohol consumption and alcohol expectancy on processing of perceptual cues of emotional expression.

We recently demonstrated that alcohol elicits a difference between men and women in perceptual threshold for facial expressions of sadness. However, this study did not include a manipulation of alcohol expectancy. Therefore, we sought to determine whether these effects may be due to the expectation of having consumed alcohol. Male and female participants (n = 100) were randomised using a balanced-placebo design to receive either an alcoholic or a non-alcoholic drink and to be told that this was alcoholic or non-alcoholic. Participants completed a psychophysical task which presented male and female faces expressing angry, happy, and sad emotions. Analysis of threshold data indicated a significant two-way interaction of drink x target emotion, reflecting a higher threshold for the detection of sad facial expressions of emotion, compared with angry or happy expressions, in the alcohol condition compared with the placebo condition. We did not observe any evidence of sex differences in these effects. Our data indicate that alcohol modifies the perceptual threshold for facial expressions of sadness. Unlike our previous report, we did not observe evidence of sex differences in these effects. Most importantly, we did not observe any evidence that these effects were due to expectancy effects associated with alcohol consumption.

Effects of acute alcohol consumption on processing of perceptual cues of emotional expression.

Alcohol consumption has been associated with increases in aggressive behaviour. However, experimental evidence of a direct association is equivocal, and mechanisms that may underlie this relationship are poorly understood. One mechanism by which alcohol consumption may increase aggressive behaviour is via alterations in processing of emotional facial cues. We investigated the effects of acute alcohol consumption on sensitivity to facial expressions of emotion. Participants attended three experimental sessions where they consumed an alcoholic drink (0.0, 0.2 or 0.4 g/kg), and completed a psychophysical task to distinguish expressive from neutral faces. The level of emotion in the expressive face varied across trials the threshold at which the expressive face was reliably identified and measured. We observed a significant three-way interaction involving emotion, participant sex and alcohol dose. Male participants showed significantly higher perceptual thresholds for sad facial expressions compared with female participants following consumption of the highest dose of alcohol. Our data indicate sex differences in the processing of facial cues of emotional expression following alcohol consumption. There was no evidence that alcohol altered the processing of angry facial expressions. Future studies should examine effects of alcohol expectancy and investigate the effects of alcohol on the miscategorisation of emotional expressions.