New synthetic cannabinoids and the potential for cardiac arrhythmia risk

Synthetic cannabinoid receptor agonists (SCRAs) have been associated with QT interval prolongation. Limited preclinical information on SCRA effects on cardiac electrogenesis results from the rapid emergence of new compounds and restricted research availability. We used two machine-learning-based tools to evaluate seven novel SCRAs' interaction potential with the hERG potassium channel, an important drug antitarget. Five SCRAs were predicted to have the ability to block the hERG channel by both prediction tools; ADB-FUBIATA was predicted to be a strong hERG blocker. ADB-5Br-INACA and ADB-4en-PINACA showed varied predictions. These findings highlight potentially proarrhythmic hERG block by novel SCRAs, necessitating detailed safety evaluations

Highlighting the hidden dangers of a ‘weak’ opioid:Deaths following use of dihydrocodeine in England (2001–2020)

BackgroundDihydrocodeine (DHC) is considered a ‘weak’ opioid, but there is evidence of its increasing misuse in overdose deaths. This research aims to analyse trends in DHC-related deaths in England relevant to source and dose of DHC, and decedent demographics.MethodsCases from England reported to the National Programme on Substance Abuse Deaths (NPSAD) where DHC was identified at post-mortem and/or implicated in death between 2001 and 2020 were extracted for analysis.Results2071 DHC-related deaths were identified. The greatest number of deaths involved illicitly obtained DHC and a significant increase in these deaths was recorded over time (r = 0.5, p = 0.03). However, there was a concurrent decline in the implication rate of DHC in causing death (r = −0.6, p &lt; 0.01). Fatalities were primarily due to accidental overdose (64.8%) and misuse was highly prevalent in combination with additional central nervous system depressants (95.3%), namely illicit heroin/morphine and diazepam. In contrast, when DHC was obtained over-the-counter (OTC) suicide mortality accounted for almost half of the deaths (42.5%). Differences in polysubstance use were also identified, with less heroin/morphine and benzodiazepine co-detection, but increased OTC codeine co-detection.ConclusionsDHC misuse in England is increasing. The pharmacological consideration of DHC as a ‘weak’ opioid may be misinterpreted by users, leading to accidental overdosing. There is an urgent need to understand increasing polypharmacy in overdose deaths. Additionally, suicides involving DHC is a potential cause for concern and a review of OTC opioid-paracetamol preparations is necessary to determine whether the benefits of these medications continue to outweigh the risks of intentional overdose.</p

Recreational ketamine-related deaths notified to the National Programme on Substance Abuse Deaths, England, 1997-2019

© 2021 The Authors. This article is distributed under the terms of the Creative Commons Attribution-NonCommercial 4.0 License (https://creativecommons.org/licenses/by-nc/4.0/) which permits non-commercial use, reproduction and distribution of the work without further permission provided the original work is attributed as specified on the SAGE and Open Access pages (https://us.sagepub.com/en-us/nam/open-access-at-sage).Background: Ketamine is a phencyclidine derivative with dissociative anaesthetic properties. Increasing numbers of individuals in England take ketamine recreationally. Information on deaths arising from such use in England is presented. Methods: Cases were extracted on 31 January 2020 from the National Programme on Substance Abuse Deaths database, based on text searches of the cause of death, coroner’s verdict and positive toxicology results for the terms ‘ketamine’ or ‘norketamine’. Findings: During 1997–2005, there were <5 deaths p.a. in which ketamine was implicated. Numbers increased until 2009 (21), plateauing until 2016; thereafter, deaths have risen to about 30 p.a. Decedents’ characteristics (N = 283): male 84.1%, mean age 31.2 (SD 10.0) years, employed 56.5%, drug use history 79.6% and living with others 60.3%. Ketamine was detected with other substances in most cases. Main (74.6%) underlying cause of death was accidental poisoning. Ketamine may have impaired judgement in other cases. Conclusions: Although controlled, recreational ketamine use and related fatalities continue to increase. Consumers need to be more aware of the potentially fatal risks they face.Peer reviewedFinal Published versio

Involvement of propranolol in suicides: A cross-sectional study using Coroner-Reported Data

Background: Propranolol is a beta-blocker medication indicated mostly for heart rhythm conditions and for physical symptoms of anxiety. Prescriptions for propranolol in the UK have increased since 2008. Recently, there have been concerns about the involvement of propranolol in intentional poisonings, but such deaths are not routinely reported. Therefore, use of coroner-reported and toxicology data enables unique investigation into the scale of involvement of propranolol in suicide. Aims: To describe the extent to which propranolol is involved in suicides, including patterns over time and characteristics of people whose suicide involved propranolol compared with other suicides. Method: Data were derived from the National Programme on Substance Use Mortality (NPSUM). All suicides and deaths of undetermined intent between 2010 and 2021 in England, Wales and Northern Ireland were extracted, and a subset was identified where propranolol was involved in death. Results: There were 4473 suicides of which 297 (6.6%) involved propranolol, with the proportion involving propranolol nearly quadrupling during the study period (3.4% v. 12.3%). Compared with all other suicides, a greater proportion of propranolol suicides were in women (56.6% v. 37.1%) and in people with diagnoses of depression (39.1% v. 27.1%) and anxiety (22.2% v. 8.6%). When suicide involved propranolol, an antidepressant was detected at post-mortem in 81.8% of deaths, most commonly a selective serotonin reuptake inhibitor (SSRIs) (51.5%), and most often citalopram (24.6%). Conclusions: A small number, but increasing proportion, of suicides reported to the NPSUM involve propranolol. Vigilance to the combined toxicity profile of medicines used alongside propranolol may be pertinent

Trends in deaths following drug use in England before, during, and after the COVID-19 lockdowns

AimThis research aimed to describe how the characteristics of deaths following drug use changed during the COVID-19 pandemic in England, and how this can inform future strategy to support the health and social care of people who use drugs in future emergency scenarios.MethodAll deaths reported to the National Programme on Substance Abuse Deaths which occurred between January 2018 and December 2021 inclusive were extracted for analysis. Exponential smoothing models were constructed to determine any differences between forecasted vs. actual trends.Key resultsFollowing the first lockdown period in England there were significant increases in the proportion of people who died at home beyond the 95% confidence bounds of the exponential smoothing model and concurrent decreases in the proportion of people who died in hospital. Whilst the overall proportion of deaths attributable to opioids did not significantly deviate from the forecasted trend, there were significant increases in methadone-related deaths and decreases in heroin/morphine-related death beyond the 95% confidence bounds. The proportion of deaths concluded as suicide increased, as did those implicating antidepressant use. There were no changes in the proportion of deaths following use of other drug classes, alcohol use in combination with psychoactive drugs, or on decedent demographics (gender, age, and drug user status). A small number of deaths due to drug use had COVID-19 infection itself listed as a cause of death (n = 23).ConclusionFor people who use drugs, the impact of the restrictions due to the COVID-19 pandemic was greater than that of infection from the virus itself. The health and social care strategy for these people needs to be pre-emptively adapted to mitigate against the specific risk factors for fatal drug overdose associated with future emergency scenarios

Cognitive function and disability in late Life: An ecological validation of the 10/66 battery of cognitive tests among community dwelling older adults in south India

This is the peer reviewed version of the following article: Krishna, M., Beulah, E., Jones, S., Sundarachari, R., Soroja .A., Kumaran, K., Kalyanaraman, K., Karat, S. C., Copeland, J. R. M., Prince, M. & Fall, C. (2015). Cognitive function and disability in late Life: An ecological validation of the 10/66 battery of cognitive tests among community dwelling older adults in South India. International Journal of Geriatric Psychiatry. 31(8) 879-891, which has been published in final form at https://doi.org/10.1002/gps.4404. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Self-ArchivingKey Points • 10/66 cognitive tests are well suited for identification of older adults with cognitive and functional impairment at a population level in LMIC setting. • Lower scores on individual domains of the 10/66 battery of cognitive tests are associated with higher levels of disability and functional impairment. • It is feasible to administer 10/66 cognitive assessments in participant's own homes in India. • 10/66 cognitive tests are education and culture fair, suitable for use in population based research in India

Robotic Automation of In Vivo Two-Photon Targeted Whole-Cell Patch-Clamp Electrophysiology

Whole-cell patch-clamp electrophysiological recording is a powerful technique for studying cellular function. While in vivo patch-clamp recording has recently benefited from automation, it is normally performed “blind,” meaning that throughput for sampling some genetically or morphologically defined cell types is unacceptably low. One solution to this problem is to use two-photon microscopy to target fluorescently labeled neurons. Combining this with robotic automation is difficult, however, as micropipette penetration induces tissue deformation, moving target cells from their initial location. Here we describe a platform for automated two-photon targeted patch-clamp recording, which solves this problem by making use of a closed loop visual servo algorithm. Our system keeps the target cell in focus while iteratively adjusting the pipette approach trajectory to compensate for tissue motion. We demonstrate platform validation with patch-clamp recordings from a variety of cells in the mouse neocortex and cerebellum

Effects of antiplatelet therapy on stroke risk by brain imaging features of intracerebral haemorrhage and cerebral small vessel diseases: subgroup analyses of the RESTART randomised, open-label trial

Background Findings from the RESTART trial suggest that starting antiplatelet therapy might reduce the risk of recurrent symptomatic intracerebral haemorrhage compared with avoiding antiplatelet therapy. Brain imaging features of intracerebral haemorrhage and cerebral small vessel diseases (such as cerebral microbleeds) are associated with greater risks of recurrent intracerebral haemorrhage. We did subgroup analyses of the RESTART trial to explore whether these brain imaging features modify the effects of antiplatelet therapy

Wild-Type Phosphoribosylpyrophosphate Synthase (PRS) from Mycobacterium tuberculosis: A Bacterial Class II PRS?

The 5-phospho-α-D-ribose 1-diphosphate (PRPP) metabolite plays essential roles in several biosynthetic pathways, including histidine, tryptophan, nucleotides, and, in mycobacteria, cell wall precursors. PRPP is synthesized from α-D-ribose 5-phosphate (R5P) and ATP by the Mycobacterium tuberculosis prsA gene product, phosphoribosylpyrophosphate synthase (MtPRS). Here, we report amplification, cloning, expression and purification of wild-type MtPRS. Glutaraldehyde cross-linking results suggest that MtPRS predominates as a hexamer, presenting varied oligomeric states due to distinct ligand binding. MtPRS activity measurements were carried out by a novel coupled continuous spectrophotometric assay. MtPRS enzyme activity could be detected in the absence of Pi. ADP, GDP and UMP inhibit MtPRS activity. Steady-state kinetics results indicate that MtPRS has broad substrate specificity, being able to accept ATP, GTP, CTP, and UTP as diphosphoryl group donors. Fluorescence spectroscopy data suggest that the enzyme mechanism for purine diphosphoryl donors follows a random order of substrate addition, and for pyrimidine diphosphoryl donors follows an ordered mechanism of substrate addition in which R5P binds first to free enzyme. An ordered mechanism for product dissociation is followed by MtPRS, in which PRPP is the first product to be released followed by the nucleoside monophosphate products to yield free enzyme for the next round of catalysis. The broad specificity for diphosphoryl group donors and detection of enzyme activity in the absence of Pi would suggest that MtPRS belongs to Class II PRS proteins. On the other hand, the hexameric quaternary structure and allosteric ADP inhibition would place MtPRS in Class I PRSs. Further data are needed to classify MtPRS as belonging to a particular family of PRS proteins. The data here presented should help augment our understanding of MtPRS mode of action. Current efforts are toward experimental structure determination of MtPRS to provide a solid foundation for the rational design of specific inhibitors of this enzyme