Substance use, racial/ethnic identity, and suicidal ideation during COVID-19 lockdown in an international adult sample.

Although research has examined disparities in suicidal ideation across multiple groups, few investigations have analyzed such disparities in the context of COVID-19 pandemic. Furthermore, there is limited research on differences within and across countries, further limiting the extent to which meaningful comparisons can be made. Therefore, this study examines risk and protective factors of suicidal ideation during COVID-19 lockdown in adults across five countries. Adults (N = 2,509) from the United States, Italy, Spain, Saudi Arabia, and India completed a survey to measure suicidal ideation, recent drug use, and sociodemographic factors. Prevalence of suicidal ideation was assessed using simple and multivariable logistic regression models, and severity of suicidal ideation was analyzed via a multinomial multivariable logistic regression. Cohen's d statistics were reported for all analyses to report effect size. In the United States subsample, racial/ethnic minorities endorsed a significantly greater prevalence of suicidal ideation compared to their White peers (aOR = 2.31, 95% CI: 1.26-4.27, d = 0.46). However, no significant racial differences in suicidal ideation were found in other countries. Past 90-day illicit drug use was associated with greater prevalence (aOR = 1.38, 95% CI: 1.06-1.80, d = 0.18) and severity (aRRR = 2.17, 95% CI: 1.33-3.53, (aRRR = 0.43) of suicidal ideation during COVID-19 lockdown. This study further highlights the social disparities that exist in suicidal ideation during COVID-19 lockdown in international samples, for which greater medical and mental health interventions are critical. As such, targeted multicomponent interventions that address substance use are important for reducing the rising prevalence and severity of COVID-related suicidal ideation.

Serotonergic neuron ribosomal proteins regulate the neuroendocrine control of Drosophila development.

The regulation of ribosome function is a conserved mechanism of growth control. While studies in single cell systems have defined how ribosomes contribute to cell growth, the mechanisms that link ribosome function to organismal growth are less clear. Here we explore this issue using Drosophila Minutes, a class of heterozygous mutants for ribosomal proteins. These animals exhibit a delay in larval development caused by decreased production of the steroid hormone ecdysone, the main regulator of larval maturation. We found that this developmental delay is not caused by decreases in either global ribosome numbers or translation rates. Instead, we show that they are due in part to loss of Rp function specifically in a subset of serotonin (5-HT) neurons that innervate the prothoracic gland to control ecdysone production. We find that these effects do not occur due to altered protein synthesis or proteostasis, but that Minute animals have reduced expression of synaptotagmin, a synaptic vesicle protein, and that the Minute developmental delay can be partially reversed by overexpression of synaptic vesicle proteins in 5-HTergic cells. These results identify a 5-HT cell-specific role for ribosomal function in the neuroendocrine control of animal growth and development.