Identification of reproductive sex-biased gene expression in Asparagopsis taxiformis (lineage 6) gametophytes.

The sub-tropical red seaweed Asparagopsis taxiformis is of significant interest due to its ability to store halogenated compounds, including bromoform, which can mitigate methane production in ruminants. Significant scale-up of aquaculture production of this seaweed is required; however, relatively little is known about the molecular mechanisms that control fundamental physiological processes, including the regulatory factors that determine sexual dimorphism in gametophytes. In this study, we used comparative RNA-sequencing analysis between different morphological parts of mature male and female A. taxiformis (lineage 6) gametophytes that resulted in greater number of sex-biased gene expression in tips (containing the reproductive structures for both sexes), compared with the somatic main axis and rhizomes. Further comparative RNA-seq against immature tips was used to identify 62 reproductive sex-biased genes (59 male-biased, 3 female-biased). Of the reproductive male-biased genes, 46% had an unknown function, while others were predicted to be regulatory factors and enzymes involved in signaling. We found that bromoform content obtained from female samples (8.5 ± 1.0 mg·g-1 dry weight) was ~10% higher on average than that of male samples (6.5 ± 1.0 mg·g-1 dry weight), although no significant difference was observed (p > 0.05). There was also no significant difference in the marine bromoform biosynthesis locus gene expression. In summary, our comparative RNA-sequencing analysis provides a first insight into the potential molecular factors relevant to gametogenesis and sexual differentiation in A. taxiformis, with potential benefits for identification of sex-specific markers.

Advanced neurobiological tools to interrogate metabolism.

Engineered neurobiological tools for the manipulation of cellular activity, such as chemogenetics and optogenetics, have become a cornerstone of modern neuroscience research. These tools are invaluable for the interrogation of the central control of metabolism as they provide a direct means to establish a causal relationship between brain activity and biological processes at the cellular, tissue and organismal levels. The utility of these methods has grown substantially due to advances in cellular-targeting strategies, alongside improvements in the resolution and potency of such tools. Furthermore, the potential to recapitulate endogenous cellular signalling has been enriched by insights into the molecular signatures and activity dynamics of discrete brain cell types. However, each modulatory tool has a specific set of advantages and limitations; therefore, tool selection and suitability are of paramount importance to optimally interrogate the cellular and circuit-based underpinnings of metabolic outcomes within the organism. Here, we describe the key principles and uses of engineered neurobiological tools. We also highlight inspiring applications and outline critical considerations to be made when using these tools within the field of metabolism research. We contend that the appropriate application of these biotechnological advances will enable the delineation of the central circuitry regulating systemic metabolism with unprecedented potential.

A Proteomic Analysis for the Red Seaweed Asparagopsis taxiformis.

The red seaweed Asparagopsis taxiformis is a promising ruminant feed additive with anti-methanogenic properties that could contribute to global climate change solutions. Genomics has provided a strong foundation for in-depth molecular investigations, including proteomics. Here, we investigated the proteome of A. taxiformis (Lineage 6) in both sporophyte and gametophyte stages, using soluble and insoluble extraction methods. We identified 741 unique non-redundant proteins using a genome-derived database and 2007 using a transcriptome-derived database, which included numerous proteins predicted to be of fungal origin. We further investigated the genome-derived proteins to focus on seaweed-specific proteins. Ontology analysis indicated a relatively large proportion of ion-binding proteins (i.e., iron, zinc, manganese, potassium and copper), which may play a role in seaweed heavy metal tolerance. In addition, we identified 58 stress-related proteins (e.g., heat shock and vanadium-dependent haloperoxidases) and 44 photosynthesis-related proteins (e.g., phycobilisomes, photosystem I, photosystem II and ATPase), which were in general more abundantly identified from female gametophytes. Forty proteins were predicted to be secreted, including ten rhodophyte collagen-alpha-like proteins (RCAPs), which displayed overall high gene expression levels. These findings provide a comprehensive overview of expressed proteins in A. taxiformis, highlighting the potential for targeted protein extraction and functional characterisation for future biodiscovery.

A highly sensitive LC-MS/MS method for quantitative determination of 7 vitamin D metabolites in mouse brain tissue.

Despite its critical role in neurodevelopment and brain function, vitamin D (vit-D) homeostasis, metabolism, and kinetics within the central nervous system remain largely undetermined. Thus, it is of critical importance to establish an accurate, highly sensitive, and reproducible method to quantitate vit-D in brain tissue. Here, we present a novel liquid chromatography tandem mass spectrometry (LC-MS/MS) method and for the first time, demonstrate detection of seven major vit-D metabolites in brain tissues of C57BL/6J wild-type mice, namely 1,25(OH)2D3, 3-epi-1,25(OH)2D3, 1,25(OH)2D2, 25(OH)D3, 25(OH)D2, 24,25(OH)2D3, and 24,25(OH)2D2. Chromatographic separation was achieved on a pentaflurophenyl column with 3 mM ammonium formate water/methanol [A] and 3 mM ammonium formate methanol/isopropanol [B] mobile phase components. Detection was by positive ion electrospray tandem mass spectrometry with the EVOQ elite triple quadrupole mass spectrometer with an Advance ultra-high-performance liquid chromatograph and online extraction system. Calibration standards of each metabolite prepared in brain matrices were used to validate the detection range, precision, accuracy, and recovery. Isotopically labelled analogues, 1,25(OH)2D3-d3, 25(OH)D3-c5, and 24,25(OH)2D3-d6, served as the internal standards for the closest molecular-related metabolite in all measurements. Standards between 1 fg/mL and 10 ng/mL were injected with a resulting linear range between 0.001 and 1 ng, with an LLOD and LLOQ of 1 pg/mL and 12.5 pg/mL, respectively. The intra-/inter-day precision and accuracy for measuring brain vit-D metabolites ranged between 0.12-11.53% and 0.28-9.11%, respectively. Recovery in acetonitrile ranged between 99.09 and 106.92% for all metabolites. Collectively, the sensitivity and efficiency of our method supersedes previously reported protocols used to measure vit-D and to our knowledge, the first protocol to reveal the abundance of 25(OH)D2, 1,25(OH)D2, and 24,25(OH)2D2, in brain tissue of any species. This technique may be important in supporting the future advancement of pre-clinical research into the function of vit-D in neurophysiological and neuropsychiatric disorders, and neurodegeneration.

An exploration of social participation in Caribbean student nurses' use of social media in their learning journey.

AIMS: To identify how social participation facilitates pre-registration student nurses learning and professional development using social media. DESIGN: A social survey using thematic analysis to explore Caribbean student nurses' views of social media usage from an open-ended question in a survey. METHODS: A qualitative analysis of student nurses from Jamaica and Trinidad and Tobago, who completed an open-ended question in a survey. Data were analysed using thematic analysis. RESULTS/FINDINGS: The three themes identified were: (1) Social media and communication; (2) Social media and self-care; and (3) Social media and learning. CONCLUSION: This paper used qualitative evidence to identify and report a new way of viewing SoMe in nursing education as a student-centred educational learning tool. SoMe can improve the effectiveness of student nurses learning, while developing fundamental skills (open-mindedness, critical thinking, professionalism and decision-making) for nursing practice. Social participation and connectivism theory are embedded in student nurses' learning journey. However, it has been used by student nurses outside the traditional university teaching and their capacity to own their personal learning. To meet the new generation of student nurses' learning needs, it is important that higher education institutions develop guidance, support and use of social media for learning to support student nurses in their education as students and also future professionals. IMPACT: This study addresses how social participation is used in social media to contribute to Caribbean student nurses' education. The main finding is the introduction of a new learning theory supporting learning using social media. This study has an impact on using social media for learning. PATIENT OR PUBLIC CONTRIBUTION: No patient or public contribution.

Freshwater Macroalgae, Oedogonium, Grown in Wastewater Reduce Diet-Induced Metabolic Syndrome in Rats.

Macroalgae produce compounds with industrial, pharmaceutical and nutritional applications. In this study, biomass from the freshwater macroalgal genus Oedogonium was grown in either treated municipal wastewater (M) or ash dam water from a coal-fired power station (D). The biomass was investigated for its metabolic responses in high-carbohydrate, high-fat diet-fed rats, a model of human metabolic syndrome. The Oedogonium biomass cultured in M contained higher amounts of K, Mg, omega-3 polyunsaturated fatty acids (PUFA), insoluble fibre and ß-carotene, while biomass grown in D contained higher amounts of Al, Fe, V, Zn, Mn and As. Biomass from M further increased body weight and inflammation in the heart and colon in high-carbohydrate, high-fat diet-fed rats. In contrast, biomass from D prevented changes in metabolic, cardiovascular and liver parameters without changing tissue histology. We suggest that increased intake of metals and metalloids through macroalgal biomass from D may decrease abdominal fat deposition while polysaccharides, PUFA and carotenoids from M may improve blood glucose responses in an obesogenic diet. Thus, macroalgal biomass grown in different wastewater sources could be acceptable for feed or food applications. This biomass could even provide potential health benefits in diet-induced metabolic syndrome.

Factors Influencing the Consumption of Seaweed amongst Young Adults.

Seaweed has been traditionally consumed in Asian and Pacific cultures, yet aside from sushi, is still not commonly eaten in Western societies. Edible seaweeds offer distinct nutritional benefits to terrestrial crops, particularly with respect to mineral and fibre content. Understanding the motivations that drive young Australians to eat seaweed is necessary for food product development and consumer marketing strategies, as well as informing future sustainable production through seaweed aquaculture and wild-harvest practices. An observational cross-sectional online survey with n = 1403 young (19-30 years) Australian seaweed consumers was conducted. The 19-item survey included closed-ended, open-ended, and Likert scale responses. Most respondents were female (89.0%), with tertiary level education or above (57.7%). Seaweed was eaten mostly as a snack (87.7%) and in home-prepared meals (30.7%). The key advantages to consumption were flavour (89.1%), nutrient content (49.1%), and health benefits (44.6%), whilst the key barriers were poor accessibility (59.5%), unaffordable pricing (46.5%), and undesirable packaging (19.0%). The consumers reported wanting more promotion to improve their knowledge about seaweed, in addition to environmentally sustainable packaging and sourcing. Pathways to overcome barriers and encourage greater seaweed consumption are discussed. Most critically, improving the promotion and environmental sustainability of seaweed products will improve intake amongst current and future consumers.

Amino acid sequence of two new milk-clotting proteases from the macroalga Gracilaria edulis.

This study is aimed at identifying and characterising the proteases we previously extracted from the red seaweed Gracilaria edulis with the potential as milk-clotting enzymes. The protease extract was first analysed by sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE) and zymography. Two protease bands with a molecular weight of 44 and 108 kDa were identified, and analysed using in-gel digestion and liquid chromatography-tandem mass spectrometry/mass spectrometry (LC-MS/MS). Eight peptides from the LC-MS/MS analysis matched those in existing protein databases but they were not related to any protease of the genera Gracilaria and Hydropuntia. Further analysis revealed that more than 80% of the peptide sequence of the algal proteases matched with those from members of the bacteria kingdom, including Gallaecimonas and Alteromonas. Among these, twelve matching homolog proteases were identified as metalloprotease and serine protease. The results indicated that the algal proteases have a close relationship with both algae and bacteria, and suggest that the proteases might have resulted from past bacterial colonisation of the algae and subsequent horizontal gene transfer between bacteria and algae.

Is the Intestinal Bacterial Community in the Australian Rabbitfish Siganus fuscescens Influenced by Seaweed Supplementation or Geography?

We recently demonstrated that dietary supplementation with seaweed leads to dramatic improvements in immune responses in S. fuscescens, a candidate species for aquaculture development in Asia. Here, to assess whether the immunostimulatory effect was facilitated by changes to the gut microbiome, we investigated the effects of those same seaweed species and four commercial feed supplements currently used in aquaculture on the bacterial communities in the hindgut of the fish. Since we found no correlations between the relative abundance of any particular taxa and the fish enhanced innate immune responses, we hypothesised that S. fuscescens might have a core microbiome that is robust to dietary manipulation. Two recently published studies describing the bacteria within the hindgut of S. fuscescens provided an opportunity to test this hypothesis and to compare our samples to those from geographically distinct populations. We found that, although hindgut bacterial communities were clearly and significantly distinguishable between studies and populations, a substantial proportion (55 of 174 taxa) were consistently detected across all populations. Our data suggest that the importance of gut microbiota to animal health and the extent to which they can be influenced by dietary manipulations might be species-specific or related to an animals' trophic level.

Understanding feedback relationships between resources, functionings and well-being: A case study of seaweed farming and artisanal processing in Indonesia.

Sen's Capability Approach is one of the most significant theoretical contributions to welfare analysis across a range of disciplines. A part of the literature argues that its conceptual linear flow-from resources to 'functionings', which result in well-being-potentially ignores more complex relations with the feedback loops where a single item could be viewed as having a different role by different people, in different contexts. We explore perceptions of existing feedback relationships in interviews with 74 women from nine seaweed farming villages in Indonesia, engaged in two distinct activities: seaweed farming and artisanal seaweed processing. We find that capability sets required for farming and for processing are distinct and in both cases we observe feedback loops. Several factors, notably social networks and transportation (motorbikes), were mentioned in almost all contexts indicating that not all resources are of equal 'value' and might yield different levels of well-being.

Demographic profiling of Caribbean and United Kingdom student nurses' use of social media for professional development.

BACKGROUND: Most students are adept in using technology and have developed skills and confidence utilising SoMe for professional purposes. SoMe is used by both registered nurses and student nurses. PURPOSE: The purpose of this study was to investigate the professional use of SoMe by student nurses in Trinidad and Tobago, Jamaica and the UK to guide, support and develop implementation of effective and appropriate use of SoMe for professional development. METHODS: An online cross-sectional survey was completed by student nurses from the three countries. Data were analysed using descriptive statistics. RESULTS: The main reason for using social media among Caribbean participants was to watch videos or short clips whereas in UK it was downloading articles. Over 75% participants of all ages believed that social media was likely to help their career. There is no social media guidance for student nurses in Trinidad and Tobago and Jamaica. CONCLUSION: Our study demonstrated that social media is embedded in student nurses' professional development throughout their education, with some variation in their use by country. Despite the fundamental place that social media plays in student nurses' professional development, there is no national or international guidance on how student nurses should use social media for professional development.

Interaction of Opioids with TLR4-Mechanisms and Ramifications.

The innate immune receptor toll-like receptor 4 (TLR4) is known as a sensor for the gram-negative bacterial cell wall component lipopolysaccharide (LPS). TLR4 activation leads to a strong pro-inflammatory response in macrophages; however, it is also recognised to play a key role in cancer. Recent studies of the opioid receptor (OR)-independent actions of opioids have identified that TLR4 can respond to opioids. Opioids are reported to weakly activate TLR4, but to significantly inhibit LPS-induced TLR4 activation. The action of opioids at TLR4 is suggested to be non-stereoselective, this is because OR-inactive (+)-isomers of opioids have been shown to activate or to inhibit TLR4 signalling, although there is some controversy in the literature. While some opioids can bind to the lipopolysaccharide (LPS)-binding cleft of the Myeloid Differentiation factor 2 (MD-2) co-receptor, pharmacological characterisation of the inhibition of opioids on LPS activation of TLR4 indicates a noncompetitive mechanism. In addition to a direct interaction at the receptor, opioids affect NF-κB activation downstream of both TLR4 and opioid receptors and modulate TLR4 expression, leading to a range of in vivo outcomes. Here, we review the literature reporting the activity of opioids at TLR4, its proposed mechanism(s), and the complex functional consequences of this interaction.

Correction: Fossil and Genetic Evidence for the Polyphyletic Nature of the Planktonic Foraminifera "Globigerinoides", and Description of the New Genus Trilobatus.

[This corrects the article DOI: 10.1371/journal.pone.0128108.].

International student nurses' use of social media for learning: A cross sectional survey.

BACKGROUND: Students use social media for sharing information and connecting with their friends, also for peer support, peer learning and student engagement. Research indicates that approximately twice the number of students were using social media for educational purposes compared to academic staff and almost all students discuss academic issues on social media. However, little is known about how diverse cohorts of student nurses use social media for specific purposes at different stages of their learning. OBJECTIVES: Identify how student nurses in each country of study use social media for learning. Identify how each generation of student nurses use social media for learning. Identify how student nurses use social media as their education progresses. DESIGN: A cross-sectional survey. SETTINGS: The study was undertaken across three countries Jamaica, Trinidad and Tobago and the UK. PARTICIPANTS: Student nurses from each of the countries that consented to participate met the inclusion criteria. METHODS: 1050 student nurses across the three countries self-completed the cross-sectional survey between March and September 2019. Data was analysed using descriptive and inferential statistics. RESULTS: WhatsApp® was the most used platform for learning amongst participants. Watching videos and downloading articles represented two-thirds of social media usage for learning. Smart phones were the most used device to access social media. Kruskal-Wallis tests were significant (≤0.001) for checking social media and messaging in lecture, use of social media for studies and classroom activities by country, generation (except classroom activities) and year of education. Use of social media for classroom activities had no significance by generation. CONCLUSION: Country, generation and year of education are factors that influence the use of social media in student nurses' learning. These should be considered by Universities in curriculum development and in teaching and learning delivery. From a pragmatic approach, social media is available and used by a majority of student nurses and can be widely assimilated into the nursing curriculum.

Metal(loid) speciation and transformation by aerobic methanotrophs.

Manufacturing and resource industries are the key drivers for economic growth with a huge environmental cost (e.g. discharge of industrial effluents and post-mining substrates). Pollutants from waste streams, either organic or inorganic (e.g. heavy metals), are prone to interact with their physical environment that not only affects the ecosystem health but also the livelihood of local communities. Unlike organic pollutants, heavy metals or trace metals (e.g. chromium, mercury) are non-biodegradable, bioaccumulate through food-web interactions and are likely to have a long-term impact on ecosystem health. Microorganisms provide varied ecosystem services including climate regulation, purification of groundwater, rehabilitation of contaminated sites by detoxifying pollutants. Recent studies have highlighted the potential of methanotrophs, a group of bacteria that can use methane as a sole carbon and energy source, to transform toxic metal (loids) such as chromium, mercury and selenium. In this review, we synthesise recent advances in the role of essential metals (e.g. copper) for methanotroph activity, uptake mechanisms alongside their potential to transform toxic heavy metal (loids). Case studies are presented on chromium, selenium and mercury pollution from the tanneries, coal burning and artisanal gold mining, respectively, which are particular problems in the developing economy that we propose may be suitable for remediation by methanotrophs. Video Abstract.

Seaweed dietary supplements enhance the innate immune response of the mottled rabbitfish, Siganus fuscescens.

Disease is one of the major bottlenecks for aquaculture development, costing the industry in excess of US $6 billion each year. The increase in pressure to phase out some traditional approaches to disease control (e.g. antibiotics) is pushing farmers to search for alternatives to treat and prevent disease outbreaks, which do not have detrimental consequences (e.g. antibiotic resistance). We tested the effects of eleven seaweed species and four established fish immunostimulants on the innate immune response (cellular and humoral immunity) of the rabbitfish Siganus fuscescens. All supplements including different seaweeds from the three groups (Chlorophyta, Phaeophyta and Rhodophyta) were included in the fish pellet at 3% (by weight) and had variably positive effects across the four innate immune parameters we measured compared to control fish. Diets supplemented with the red seaweed Asparagopsis taxiformis and the brown seaweed Dictyota intermedia led to the largest boosts in humoral and cellular innate immune defences, including particularly significant increases in haemolytic activity. Diets supplemented with Ulva fasciata also led to promising positive effects on the fish innate immune responses. We conclude that dietary seaweed supplements can boost the immune response of S. fuscescens and thus the top three species highlighted in this study should be further investigated for this emerging aquaculture species and other fish species.

Application of omics research in seaweeds with a focus on red seaweeds.

Targeted 'omics' research for seaweeds, utilizing various computational and informatics frameworks, has the potential to rapidly develop our understanding of biological processes at the molecular level and contribute to solutions for the most pressing environmental and social issues of our time. Here, a systematic review into the current status of seaweed omics research was undertaken to evaluate the biological diversity of seaweed species investigated (red, green and brown phyla), the levels to which the work was undertaken (from full genome to transcripts, proteins or metabolites) and the field of research to which it has contributed. We report that from 1994 to 2021 the majority of seaweed omics research has been performed on the red seaweeds (45% of total studies), with more than half of these studies based upon two genera Pyropia and Gracilaria. A smaller number of studies examined brown seaweed (key genera Saccharina and Sargassum) and green seaweed (primarily Ulva). Overall, seaweed omics research is most highly associated with the field of evolution (46% of total studies), followed by the fields of ecology, natural products and their biosynthesis, omics methodology and seaweed-microbe interactions. Synthesis and specific outcomes derived from omics studies in the red seaweeds are provided. Together, these studies have provided a broad-scale interrogation of seaweeds, facilitating our ability to answer fundamental queries and develop applied outcomes. Crucial to the next steps will be establishing analytical tools and databases that can be more broadly utilized by practitioners and researchers across the globe because of their shared interest in the key seaweed genera.

Demographic profiling of Caribbean and United Kingdom student nurses' use of social media for professional development

Background: Most students are adept in using technology and have developed skills and confidence utilising SoMe for professional purposes. SoMe is used by both registered nurses and student nurses. Purpose: The purpose of this study was to investigate the professional use of SoMe by student nurses in Trinidad and Tobago, Jamaica and the UK to guide, support and develop implementation of effective and appropriate use of SoMe for professional development. Methods: An online cross-sectional survey was completed by student nurses from the three countries. Data were analysed using descriptive statistics. Results: The main reason for using social media among Caribbean participants was to watch videos or short clips whereas in UK it was downloading articles. Over 75% participants of all ages believed that social media was likely to help their career. There is no social media guidance for student nurses in Trinidad and Tobago and Jamaica. Conclusion: Our study demonstrated that social media is embedded in student nurses' professional development throughout their education, with some variation in their use by country. Despite the fundamental place that social media plays in student nurses' professional development, there is no national or international guidance on how student nurses should use social media for professional development.

International student nurses' use of social media for learning: A cross sectional survey

Background: Students use social media for sharing information and connecting with their friends, also for peer support, peer learning and student engagement. Research indicates that approximately twice the number of students were using social media for educational purposes compared to academic staff and almost all students discuss academic issues on social media. However, little is known about how diverse cohorts of student nurses use social media for specific purposes at different stages of their learning. Objectives: Identify how student nurses in each country of study use social media for learning. Identify how each generation of student nurses use social media for learning. Identify how student nurses use social media as their education progresses. Design: A cross-sectional survey. Settings: The study was undertaken across three countries Jamaica, Trinidad and Tobago and the UK. Participants: Student nurses from each of the countries that consented to participate met the inclusion criteria. Methods: 1050 student nurses across the three countries self-completed the cross-sectional survey between March and September 2019. Data was analysed using descriptive and inferential statistics. Results: WhatsApp® was the most used platform for learning amongst participants. Watching videos and downloading articles represented two-thirds of social media usage for learning. Smart phones were the most used device to access social media. Kruskal-Wallis tests were significant (≤0.001) for checking social media and messaging in lecture, use of social media for studies and classroom activities by country, generation (except classroom activities) and year of education. Use of social media for classroom activities had no significance by generation. Conclusion: Country, generation and year of education are factors that influence the use of social media in student nurses' learning. These should be considered by Universities in curriculum development and in teaching and learning delivery. From a pragmatic approach, social media is available and used by a majority of student nurses and can be widely assimilated into the nursing curriculum

The non-selective adenosine antagonist theophylline reverses the effects of dopamine antagonism on tremor, motor activity and effort-based decision-making.

Considerable evidence indicates that adenosine and dopamine systems interact in the regulation of basal ganglia function. Nonselective adenosine antagonists such as the methylxanthine caffeine as well as selective adenosine A2A antagonists have been shown to produce antiparkinsonian and antidepressant effects in animal models. The present studies were conducted to assess if another methylxantine, theophylline, can reverse motor and motivational impairments induced by dopamine antagonism in rats. RESULTS: Theophylline (3.75-30.0 mg/kg, IP) reversed tremulous jaw movements (TJMs), catalepsy, and locomotor suppression induced by the dopamine D2 antagonist pimozide. It also reversed TJMs induced by the muscarinic receptor agonist pilocarpine, which is a well-known tremorogenic agent. Parallel studies assessed the ability of theophylline (5.0-20.0 mg/kg, IP) to reverse the changes in effort-related choice behavior induced by the dopamine D1 antagonist ecopipam (0.2 mg/kg, IP) and the D2 antagonist haloperidol (0.1 mg/kg, IP). Rats were tested on two different operant choice tasks which assess the tendency to work for a preferred reinforcer by lever pressing (for palatable pellets or a high 5% sucrose solution) vs. approaching and consuming a less preferred reinforcer (freely available lab chow or a less concentrated 0.3% sucrose solution). Theophylline restored food and sucrose-reinforced lever pressing in animals treated with the D2 antagonist. However, it was unable to reverse the effects of the D1 antagonist. Overall, the effects of theophylline resembled those previously reported for adenosine A2A antagonists, and suggest that theophylline could be clinically useful for the treatment of motor and motivational symptoms in humans.