Embryonic Stem Cell-Derived Neurons Grown on Multi-Electrode Arrays as a Novel In vitro Bioassay for the Detection of Clostridium botulinum Neurotoxins

Clostridium botulinum neurotoxins (BoNTs) are the most poisonous naturally occurring protein toxins known to mankind and are the causative agents of the severe and potentially life-threatening disease botulism. They are also known for their application as cosmetics and as unique bio-pharmaceuticals to treat an increasing number of neurological and non-neurological disorders. Currently, the potency of biologically active BoNT for therapeutic use is mainly monitored by the murine LD50-assay, an ethically disputable test causing suffering and death of a considerable number of mice. The aim of this study was to establish an in-vitro assay as an alternative to the widely used in-vivo mouse bioassay. We report a novel BoNT detection assay using mouse embryonic stem cell-derived neurons (mESN) cultured on multi-electrode arrays. After 21 days in culture, the mESN formed a neuronal network showing spontaneous bursting activity based on functional synapses and express the necessary target proteins for BoNTs. Treating cultures for 6 h with 16.6 pM of BoNT serotype A and incubation with 1.66 pM BoNT/A or 33 Units/ml of Botox® for 24 h lead to a significant reduction of both spontaneous network bursts and average spike rate. This data suggests that mESN cultured on multi-electrode arrays pose a novel, biologically relevant model that can be used to detect and quantify functional BoNT effects, thus accelerating BoNT research while decreasing animal use

Free fatty acid receptors in GtoPdb v.2023.1

Free fatty acid receptors (FFA, nomenclature as agreed by the NC-IUPHAR Subcommittee on free fatty acid receptors [116, 27]) are activated by free fatty acids. Long-chain saturated and unsaturated fatty acids (including C14.0 (myristic acid), C16:0 (palmitic acid), C18:1 (oleic acid), C18:2 (linoleic acid), C18:3, (α-linolenic acid), C20:4 (arachidonic acid), C20:5,n-3 (EPA) and C22:6,n-3 (docosahexaenoic acid)) activate FFA1 [9, 54, 64] and FFA4 receptors [45, 52, 94], while short chain fatty acids (C2 (acetic acid), C3 (propanoic acid), C4 (butyric acid) and C5 (pentanoic acid)) activate FFA2 [10, 66, 90] and FFA3 [10, 66] receptors. The crystal structure for agonist bound FFA1 has been described [113]

Free fatty acid receptors (version 2019.4) in the IUPHAR/BPS Guide to Pharmacology Database

Free fatty acid receptors (FFA, nomenclature as agreed by the NC-IUPHAR Subcommittee on free fatty acid receptors [111, 24]) are activated by free fatty acids. Long-chain saturated and unsaturated fatty acids (including C14.0 (myristic acid), C16:0 (palmitic acid), C18:1 (oleic acid), C18:2 (linoleic acid), C18:3, (α-linolenic acid), C20:4 (arachidonic acid), C20:5,n-3 (EPA) and C22:6,n-3 (docosahexaenoic acid)) activate FFA1 [8, 50, 60] and FFA4 receptors [41, 48, 90], while short chain fatty acids (C2 (acetic acid), C3 (propanoic acid), C4 (butyric acid) and C5 (pentanoic acid)) activate FFA2 [9, 62, 86] and FFA3 [9, 62] receptors. The crystal structure for agonist bound FFA1 has been described [108]

Ligand biological activity predicted by cleaning positive and negative chemical correlations.

Predicting ligand biological activity is a key challenge in drug discovery. Ligand-based statistical approaches are often hampered by noise due to undersampling: The number of molecules known to be active or inactive is vastly less than the number of possible chemical features that might determine binding. We derive a statistical framework inspired by random matrix theory and combine the framework with high-quality negative data to discover important chemical differences between active and inactive molecules by disentangling undersampling noise. Our model outperforms standard benchmarks when tested against a set of challenging retrospective tests. We prospectively apply our model to the human muscarinic acetylcholine receptor M1, finding four experimentally confirmed agonists that are chemically dissimilar to all known ligands. The hit rate of our model is significantly higher than the state of the art. Our model can be interpreted and visualized to offer chemical insights about the molecular motifs that are synergistic or antagonistic to M1 agonism, which we have prospectively experimentally verified

Patron offending and intoxication in night time entertainment districts (POINTED) : a study protocol

Risky alcohol consumption is the subject of considerable community concern in Australia and internationally, particularly the risky drinking practices of young people consuming alcohol in the night-time economy. This study will determine some of the factors and correlates associated with alcohol-related risk-taking, offending and harm in and around licensed venues and night-time entertainment precincts across five Australian cities (three metropolitan and two regional). The primary aim of the study is to measure levels of pre-drinking, drinking in venues, intoxication, illicit drug use and potentially harmful drinking practices (such as mixing with energy drinks) of patrons in entertainment areas, and relating this to offending, risky behaviour and harms experienced. The study will also investigate the effects of license type, trading hours, duration of drinking episodes and geographical location on intoxication, offending, risk-taking and experience of harm. Data collection involves patron interviews (incorporating breathalysing and drug testing) with 7500 people attending licensed venues. Intensive venue observations (n=112) will also be undertaken in a range of venues, including pubs, bars and nightclubs. The information gathered through this study will inform prevention and enforcement approaches of policy makers, police and venue staff.<br /

Manifestations of early brain recovery associated with abstinence from alcoholism

Chronic alcohol abuse results in morphological, metabolic, and functional brain damage which may, to some extent, be reversible with early effects upon abstinence. Although morphometric, spectroscopic, and neuropsychological indicators of cerebral regeneration have been described previously, the overall amount and spatial preference of early brain recovery attained by abstinence and its associations with other indicators of regeneration are not well established. We investigated global and local brain volume changes in a longitudinal two-timepoint study with T1-weighted MRI at admission and after short-term (6-7 weeks) sobriety follow-up in 15 uncomplicated, recently detoxified alcoholics. Volumetric brain gain was related to metabolic and neuropsychological recovery. On admission and after short-term abstinence, structural image evaluation using normalization of atrophy (SIENA), its voxelwise statistical extension to multiple subjects, proton MR spectroscopy (1H-MRS), and neuropsychological tests were applied. Upon short-term sobriety, 1H-MRS levels of cerebellar choline and frontomesial N-acetylaspartate (NAA) were significantly augmented. Automatically detected global brain volume gain amounted to nearly two per cent on average and was spatially significant around the superior vermis, perimesencephalic, periventricular and frontal brain edges. It correlated positively with the percentages of cerebellar and frontomesial choline increase, as detected by 1H-MRS. Moreover, frontomesial NAA gains were associated with improved performance on the d2-test of attention. In 10 age- and gender-matched healthy control subjects, no significant brain volume or metabolite changes were observed. Although cerebral osmotic regulations may occur initially upon sobriety, significant increases of cerebellar choline and frontomesial NAA levels detected at stable brain water integrals and creatine concentrations, serum electrolytes and red blood cell indices in our patient sample suggest that early brain recovery through abstinence does not simply reflect rehydration. Instead, even the adult human brain and particularly its white matter seems to possess genuine capabilities for regrowth. Our findings emphasize metabolic as well as regionally distinct morphological capacities for partial brain recovery from toxic insults of chronic alcoholism and substantiate early measurable benefits of therapeutic sobriety. Further understanding of the precise mechanisms of this recovery may become a valuable model of brain regeneration with relevance for other disorder

Missed opportunities for diagnosing brain tumours in primary care: a qualitative study of patient experiences.

BACKGROUND: Brain tumours are uncommon, and have extremely poor outcomes. Patients and GPs may find it difficult to recognise early symptoms because they are often non-specific and more likely due to other conditions. AIM: To explore patients' experiences of symptom appraisal, help seeking, and routes to diagnosis. DESIGN AND SETTING: Qualitative study set in the East and North West of England. METHOD: In-depth interviews with adult patients recently diagnosed with a primary brain tumour and their family members were analysed thematically, using the Model of Pathways to Treatment as a conceptual framework. RESULTS: Interviews were carried out with 39 patients. Few participants (n = 7; 18%) presented as an emergency without having had a previous GP consultation; most had had one (n = 15; 38%), two (n = 9; 23%), or more (n = 8; 21%) GP consultations. Participants experienced multiple subtle 'changes' rather than 'symptoms', often noticed by others rather than the patient, which frequently led to loss of interest or less ability to engage with daily living activities. The most common changes were in cognition (speaking, writing, comprehension, memory, concentration, and multitasking), sleep, and other 'head feelings' such as dizziness. Not all patients experienced a seizure, and few seizures were experienced 'out of the blue'. Quality of communication in GP consultations played a key role in patients' subsequent symptom appraisal and the timing of their decision to re-consult. CONCLUSION: Multiple subtle changes and frequent GP visits often precede brain tumour diagnosis, giving possible diagnostic opportunities for GPs. Refined community symptom awareness and GP guidance could enable more direct pathways to diagnosis, and potentially improve patient experiences and outcomes