Is approving esketamine as an antidepressant for treatment resistant depression associated with recreational use and risk perception of ketamine? Results from a longitudinal and cross-sectional survey in nightlife attendees

Background Esketamine was licensed for use in treatment resistant depression by the European Medicines Agency in December 2019. It is unclear whether this new approval has lowered the risk perception of recreational ketamine use. This is important given a recent increase in recreational ketamine use. Methods This study expanded on an existing longitudinal online study of the nightlife scene, by adding an additional longitudinal assessment as well as a new cross-sectional sample. Participants had to be aged 18–34 years, reside in the UK and have attended at least 6 electronic music events in the past year. The likelihood of increasing recreational ketamine use due to the approval, attitudes towards and risk perception of medical ketamine use and experiences resulting from recreational ketamine use were collected after the approval. Changes in ketamine use and frequency were assessed longitudinally before and after the approval. Results The overall sample size was 2415: 414 longitudinal (57% retention rate) and 2001 new cross-sectional participants. The majority indicated no change in their likelihood of using recreational ketamine due to the approval of esketamine (87%). Longitudinal participants did not indicate an increase in past 12 month use or frequency after the approval. Only one-third of participants reported being aware of the approval. Participants previously aware showed greater overall support for medical use of ketamine than participants previously unaware of the change. However, an equally high risk was assigned to the recreational use of ketamine in both groups. Ketamine users indicated both increases as well as decreases in depression and anxiety as a result of ketamine use. Conclusion The introduction of esketamine as an antidepressant was not associated with a change in the risk perception of recreational ketamine use in most participants, nor was it longitudinally associated with increased use. Potential negative effects of recreational ketamine use on mental health, as users in this sample reported, should be clearly communicated when discussing the benefits of (es-) ketamine in a therapeutic context

Polydrug Use Typologies of Regular Ecstasy Users Visiting Electronic Dance Music Events:A Latent Class Analysis

Introduction: Polydrug use patterns among young adults using ecstasy vary, as well as their willingness to change them. Polydrug use patterns are likely associated with different adverse health outcomes. It is unknown whether polydrug use patterns of young adults who use ecstasy are similar in different countries. This study aims to identify and compare polydrug use patterns and willingness to change them of young adults that use ecstasy in the United Kingdom (UK) and the Netherlands (NL), two countries with a high prevalence of ecstasy use and a large electronic dance music (EDM) scene. Methods: The data from the online cross-sectional Electronic Music Scene Survey were used in a latent class analysis. The binary indicators used in the estimation were past-year substance use of 21 different substances. The sample consisted of young adult ecstasy users that regularly visit EDM events (age 18–34). Results: A total of 1, 077 respondents from the UK (age M = 23.1) and 1, 178 from the NL (age M = 23.7) that regularly visit EDM events were included in the analyses. In both countries, three polydrug use patterns of ecstasy users were identified based on Bayesian Information Criterion fit indices: a traditional polydrug use class (UK: 28%; NL: 40%), a stimulant and ketamine polydrug use class (UK: 48%; NL: 52%), and an extensive polydrug use class (UK: 24%; NL: 8%) characterized by substantial use of stimulants, depressant, and psychedelic substances. Overall, young adults that used ecstasy in the UK consumed 3, 4-methylenedioxymeth-amphetamine (MDMA) more often as powder/crystalline and at higher dosages compared to young adults in the NL who preferred MDMA tablets. Regardless of polydrug class or country, most respondents indicated that they had the intention to reduce but not quit their use. Conclusion: In both countries, structurally similar polydrug use patterns among young adults that use ecstasy were found, while the use frequencies of individual substances and preferred MDMA form varied between the countries.</p

Conservation of the structural and functional architecture of encapsulated ferritins in bacteria and archaea

Ferritins are a large family of intracellular proteins that protect the cell from oxidative stress by catalytically converting Fe(II) into less toxic Fe(III) and storing iron minerals within their core. Encapsulated ferritins (EncFtn) are a sub-family of ferritin-like proteins, which are widely distributed in all bacterial and archaeal phyla. The recently characterized Rhodospirillum rubrum EncFtn displays an unusual structure when compared with classical ferritins, with an open decameric structure that is enzymatically active, but unable to store iron. This EncFtn must be associated with an encapsulin nanocage in order to act as an iron store. Given the wide distribution of the EncFtn family in organisms with diverse environmental niches, a question arises as to whether this unusual structure is conserved across the family. Here, we characterize EncFtn proteins from the halophile Haliangium ochraceum and the thermophile Pyrococcus furiosus, which show the conserved annular pentamer of dimers topology. Key structural differences are apparent between the homologues, particularly in the centre of the ring and the secondary metal-binding site, which is not conserved across the homologues. Solution and native mass spectrometry analyses highlight that the stability of the protein quaternary structure differs between EncFtn proteins from different species. The ferroxidase activity of EncFtn proteins was confirmed, and we show that while the quaternary structure around the ferroxidase centre is distinct from classical ferritins, the ferroxidase activity is still inhibited by Zn(II). Our results highlight the common structural organization and activity of EncFtn proteins, despite diverse host environments and contexts within encapsulins

Pore dynamics and asymmetric cargo loading in an encapsulin nanocompartment

Encapsulins are protein nanocompartments that house various cargo enzymes, including a family of decameric ferritin-like proteins. Here, we study a recombinant Haliangium ochraceum encapsulin:encapsulated ferritin complex using cryo–electron microscopy and hydrogen/deuterium exchange mass spectrometry to gain insight into the structural relationship between the encapsulin shell and its protein cargo. An asymmetric single-particle reconstruction reveals four encapsulated ferritin decamers in a tetrahedral arrangement within the encapsulin nanocompartment. This leads to a symmetry mismatch between the protein cargo and the icosahedral encapsulin shell. The encapsulated ferritin decamers are offset from the interior face of the encapsulin shell. Using hydrogen/deuterium exchange mass spectrometry, we observed the dynamic behavior of the major fivefold pore in the encapsulin shell and show the pore opening via the movement of the encapsulin A-domain. These data will accelerate efforts to engineer the encapsulation of heterologous cargo proteins and to alter the permeability of the encapsulin shell via pore modifications

Polydrug Use Typologies of Regular Ecstasy Users Visiting Electronic Dance Music Events: A Latent Class Analysis

INTRODUCTION: Polydrug use patterns among young adults using ecstasy vary, as well as their willingness to change them. Polydrug use patterns are likely associated with different adverse health outcomes. It is unknown whether polydrug use patterns of young adults who use ecstasy are similar in different countries. This study aims to identify and compare polydrug use patterns and willingness to change them of young adults that use ecstasy in the United Kingdom (UK) and the Netherlands (NL), two countries with a high prevalence of ecstasy use and a large electronic dance music (EDM) scene. METHODS: The data from the online cross-sectional Electronic Music Scene Survey were used in a latent class analysis. The binary indicators used in the estimation were past-year substance use of 21 different substances. The sample consisted of young adult ecstasy users that regularly visit EDM events (age 18-34). RESULTS: A total of 1,077 respondents from the UK (age M = 23.1) and 1,178 from the NL (age M = 23.7) that regularly visit EDM events were included in the analyses. In both countries, three polydrug use patterns of ecstasy users were identified based on Bayesian Information Criterion fit indices: a traditional polydrug use class (UK: 28%; NL: 40%), a stimulant and ketamine polydrug use class (UK: 48%; NL: 52%), and an extensive polydrug use class (UK: 24%; NL: 8%) characterized by substantial use of stimulants, depressant, and psychedelic substances. Overall, young adults that used ecstasy in the UK consumed 3,4-methylenedioxymeth-amphetamine (MDMA) more often as powder/crystalline and at higher dosages compared to young adults in the NL who preferred MDMA tablets. Regardless of polydrug class or country, most respondents indicated that they had the intention to reduce but not quit their use. CONCLUSION: In both countries, structurally similar polydrug use patterns among young adults that use ecstasy were found, while the use frequencies of individual substances and preferred MDMA form varied between the countries

Drug use changes at the individual level : Results from a longitudinal, multisite survey in young europeans frequenting the nightlife scene

Background: Monitoring emerging trends in the increasingly dynamic European drug market is vital; however, information on change at the individual level is scarce. In the current study, we investigated changes in drug use over 12 months in European nightlife attendees. Method: In this longitudinal online survey, changes in substances used, use frequency in continued users, and relative initiation of use at follow-up were assessed for 20 different substances. To take part, participants had to be aged 18–34 years; be from Belgium, Italy, the Netherlands, Sweden, or the UK; and have attended at least 6 electronic music events in the past 12 months at baseline. Of 8,045 volunteers at baseline, 2,897 completed the survey at both time points (36% follow-up rate), in 2017 and 2018. Results: The number of people using ketamine increased by 21% (p < 0.001), and logarithmized frequency of use in those continuing use increased by 15% (p < 0.001; 95% CI: 0.07–0.23). 4-Fluoroamphetamine use decreased by 27% (p < 0.001), and logarithmized frequency of use in continuing users decreased by 15% (p < 0.001, 95% CI: −0.48 to −0.23). The drugs with the greatest proportion of relative initiation at follow-up were synthetic cannabinoids (73%, N = 30), mephedrone (44%, N = 18), alkyl nitrites (42%, N = 147), synthetic dissociatives (41%, N = 15), and prescription opioids (40%, N = 48). Conclusions: In this European nightlife sample, ketamine was found to have the biggest increase in the past 12 months, which occurred alongside an increase in frequency of use in continuing users. The patterns of uptake and discontinuation of alkyl nitrates, novel psychoactive substances, and prescription opioids provide new information that has not been captured by existing cross-sectional surveys. These findings demonstrate the importance of longitudinal assessments of drug use and highlight the dynamic nature of the European drug landscape

The adaptive designs CONSORT extension (ACE) statement: a checklist with explanation and elaboration guideline for reporting randomised trials that use an adaptive design

Abstract: Adaptive designs (ADs) allow pre-planned changes to an ongoing trial without compromising the validity of conclusions and it is essential to distinguish pre-planned from unplanned changes that may also occur. The reporting of ADs in randomised trials is inconsistent and needs improving. Incompletely reported AD randomised trials are difficult to reproduce and are hard to interpret and synthesise. This consequently hampers their ability to inform practice as well as future research and contributes to research waste. Better transparency and adequate reporting will enable the potential benefits of ADs to be realised. This extension to the Consolidated Standards Of Reporting Trials (CONSORT) 2010 statement was developed to enhance the reporting of randomised AD clinical trials. We developed an Adaptive designs CONSORT Extension (ACE) guideline through a two-stage Delphi process with input from multidisciplinary key stakeholders in clinical trials research in the public and private sectors from 21 countries, followed by a consensus meeting. Members of the CONSORT Group were involved during the development process. The paper presents the ACE checklists for AD randomised trial reports and abstracts, as well as an explanation with examples to aid the application of the guideline. The ACE checklist comprises seven new items, nine modified items, six unchanged items for which additional explanatory text clarifies further considerations for ADs, and 20 unchanged items not requiring further explanatory text. The ACE abstract checklist has one new item, one modified item, one unchanged item with additional explanatory text for ADs, and 15 unchanged items not requiring further explanatory text. The intention is to enhance transparency and improve reporting of AD randomised trials to improve the interpretability of their results and reproducibility of their methods, results and inference. We also hope indirectly to facilitate the much-needed knowledge transfer of innovative trial designs to maximise their potential benefits. In order to encourage its wide dissemination this article is freely accessible on the BMJ and Trials journal websites.“To maximise the benefit to society, you need to not just do research but do it well” Douglas G Altma