Circular RNA migration in agarose gel electrophoresis.

Circular RNAs are garnering increasing interest as potential regulatory RNAs and a format for gene expression. The characterization of circular RNA using analytical techniques commonly employed in the literature, such as gel electrophoresis, can, under differing conditions, yield different results when attempting to distinguish circular RNA from linear RNA of similar molecular weights. Here, we describe circular RNA migration in different conditions, analyzed by gel electrophoresis and high-performance liquid chromatography (HPLC). We characterize key parameters that affect the migration pattern of circular RNA in gel electrophoresis systems, which include gel type, electrophoresis time, sample buffer composition, and voltage. Finally, we demonstrate the utility of orthogonal analytical tests for circular RNA that take advantage of its covalently closed structure to further distinguish circular RNA from linear RNA following in vitro synthesis.

RNA Circularization Diminishes Immunogenicity and Can Extend Translation Duration In Vivo.

Circular RNAs (circRNAs) are a class of single-stranded RNAs with a contiguous structure that have enhanced stability and a lack of end motifs necessary for interaction with various cellular proteins. Here, we show that unmodified exogenous circRNA is able to bypass cellular RNA sensors and thereby avoid provoking an immune response in RIG-I and Toll-like receptor (TLR) competent cells and in mice. The immunogenicity and protein expression stability of circRNA preparations are found to be dependent on purity, with small amounts of contaminating linear RNA leading to robust cellular immune responses. Unmodified circRNA is less immunogenic than unmodified linear mRNA in vitro, in part due to the evasion of TLR sensing. Finally, we provide the first demonstration to our knowledge of exogenous circRNA delivery and translation in vivo, and we show that circRNA translation is extended in adipose tissue in comparison to unmodified and uridine-modified linear mRNAs.

Psychotropic drug use among children and adolescents in the Nordic countries: a systematic review.

The Nordic countries have rather homogenous populations and similar health care systems, and one could therefore expect comparable levels of psychopathology and psychotropic drug use. However, recent studies show pronounced variations in psychotropic drug use among children and adolescents from different Nordic countries. Therefore, we aimed to conduct a systematic review of the literature examining the use of psychotropic drugs among children and adolescents in the Nordic countries. This review followed PRISMA guidelines. We searched PsycINFO, EMBASE and MEDLINE for population-based studies published 2010 or later that investigated prevalent or incident use of antidepressants, psychostimulants, antipsychotics, hypnotics, anxiolytics, and mood stabilizers among 0-19-year-olds in the Nordic countries. Two reviewers assessed all studies. Twenty-two out of 2142 eligible studies were included in the final review covering data collected from 1995 to 2018. The use of psychotropic drugs, except for anxiolytics, increased in most of the Nordic countries, but at different rates. Prevalent use of antidepressants was two to four times higher among Swedish children and adolescents compared to Danish and Norwegian peers. Prevalent use of psychostimulants, on the other hand, was two to sixfold higher in Iceland compared to the other Nordic countries. Finally, the prevalence of antipsychotic use was threefold higher in Finland compared to Sweden, Denmark, and Norway. This systematic review provides a thorough overview of psychotropic treatment of youths in the Nordic countries. We demonstrate a pronounced national variation in use of psychotropics that should be addressed further to facilitate rational pharmacotherapy in youths with psychiatric disorders.

A Wnt-producing niche drives proliferative potential and progression in lung adenocarcinoma.

The heterogeneity of cellular states in cancer has been linked to drug resistance, cancer progression and the presence of cancer cells with properties of normal tissue stem cells. Secreted Wnt signals maintain stem cells in various epithelial tissues, including in lung development and regeneration. Here we show that mouse and human lung adenocarcinomas display hierarchical features with two distinct subpopulations, one with high Wnt signalling activity and another forming a niche that provides the Wnt ligand. The Wnt responder cells showed increased tumour propagation ability, suggesting that these cells have features of normal tissue stem cells. Genetic perturbation of Wnt production or signalling suppressed tumour progression. Small-molecule inhibitors targeting essential posttranslational modification of Wnt reduced tumour growth and markedly decreased the proliferative potential of lung cancer cells, leading to improved survival of tumour-bearing mice. These results indicate that strategies for disrupting pathways that maintain stem-like and niche cell phenotypes can translate into effective anti-cancer therapies.

Maternal prenatal stress and postnatal depressive symptoms: discrepancy between mother and teacher reports of toddler psychological problems.

PURPOSE: Maternal prenatal stress and postnatal depression are reported to increase the risk for early offspring psychological problems. We examined whether these two stressors predicted toddler emotional or behavioral problems based on the mother and teacher reports, respectively. METHODS: A longitudinal study within the Odense Child Cohort (OCC). Prenatal stress was assessed (gestation week 28) using Cohen's Perceived Stress Scale (PSS). Depressive symptoms were assessed (3 months after birth) using the Edinburgh Postnatal Depression Scale (EPDS). Behavioral and emotional problems were assessed by mothers using the preschool version of Child Behaviour Checklist (CBCL) and by teachers using the caregiver-teacher report form (CTR-F). RESULTS: N = 1302 mother-child dyads were included. CBCL (N = 1302) was collected at 29 months (SD 5.3) and C-TRF (N = 989) at 32.6 months (SD 6.9). N = 70 mothers (5.4%) were at high risk for postnatal depression (EPDS score > 12). Generalized additive models showed that prenatal stress (increase of + 1 on PSS-10 total score) predicted an increase in CBCL (+ 0.011) and C-TRF (+ 0.015) total scores. Postnatal depressive symptoms (increase of + 1 on EPDS total score) only predicted an increase in CBCL total score (+ 0.026). CONCLUSION: Prenatal maternal stress was a significant predictor of both mother and teacher reported toddler emotional and behavioral problems, although effect sizes were small. Postnatal depressive symptoms were associated with increased maternal (but not teacher) reporting of toddler problems. Mothers reported more toddler psychological problems than teachers, and the mother-teacher discrepancy was positively correlated to maternal postnatal depressive symptoms.

Trends in antidepressant use among children and adolescents: a Scandinavian drug utilization study.

OBJECTIVE: To compare antidepressant utilization in individuals aged 5-19 years from the Scandinavian countries. METHODS: A population-based drug utilization study using publicly available data of antidepressant use from Denmark, Norway, and Sweden. RESULTS: In the study period from 2007 to 2017, the proportion of antidepressant users increased markedly in Sweden (9.3-18.0/1000) compared to Norway (5.1-7.6/1000) and Denmark (9.3-7.5/1000). In 2017, the cumulated defined daily doses (DDD) of selective serotonin reuptake inhibitors were 5611/1000 inhabitants in Sweden, 2709/1000 in Denmark, and 1848/1000 in Norway. The use of 'other antidepressants' (ATC code N06AX) also increased in Sweden with a higher DDD in 2017 (497/1000) compared to Denmark (225/1000) and Norway (170/1000). The use of tricyclic antidepressants was generally low in 2017 with DDDs ranging between 30-42 per 1000. The proportion of antidepressant users was highest among 15- to 19-year-old individuals. Girls were more likely to receive treatment than boys, and the treated female/male ratios per 1000 were similar in Sweden (2.39), Denmark (2.44), and Norway (2.63). CONCLUSION: Even in highly comparable healthcare systems like the Scandinavian countries', variation in antidepressant use is considerable. Swedish children and adolescents have a markedly higher and still increasing use of antidepressants compared to Danish and Norwegian peers.

Gender-age interaction in incidence rates of childhood emotional disorders.

BACKGROUND: The post-pubertal association of female gender with emotional disorder is a robust finding. However, studies exploring the association of gender and emotional disorders before puberty are few and present diverging results. The aim of this study was to present gender-specific incidence rates of emotional disorders throughout childhood. METHOD: This is a population-based cohort study of 907,806 Danish 3- to 18-year-olds. The outcome was assignment of an emotional disorder diagnosis based on in-patient and out-patient data from The Danish Psychiatric Central Register. Outcome measures were incidence rates and cumulative incidences for unipolar depressive disorder (ICD-10: F32-F33), anxiety disorders (ICD-10: F40-F42), and emotional disorders with onset specific to childhood (ICD-10: F93). RESULTS: Pre-pubertal incidence rates for depressive and anxiety disorders were higher for boys than girls. At age 12 years the pattern reversed. The cumulative incidence for any emotional disorder (F32-F33, F40-F42, F93) on the 11th birthday was 0.52% (95% CI 0.50-0.55) for boys and 0.31% (95% CI 0.29-0.33) for girls. On the 19th birthday cumulative incidence was 2.33% (95% CI 2.24-2.43) for boys and 3.77% (95% CI 3.64-3.90) for girls. The pre-pubertal male preponderance was also significant for depressive disorders (F32-F33, p = 0.00144) and anxiety disorders (F40-F42, F93, p < 0.00001) separately. CONCLUSIONS: Emotional disorders seem to display a male preponderance before the age of 12 years and a female preponderance thereafter. Studies exploring this gender-age interaction are needed. Still, the results question the general assumption that females throughout the lifespan are more at risk for emotional disorders than males.

Risk of somatic diseases in patients with eating disorders: the role of comorbid substance use disorders.

AIMS: Eating disorders (EDs) and substance use disorders (SUDs) often co-occur, and both involve somatic diseases. So far, no study has considered whether comorbid SUDs may impact somatic disease risk in patients with EDs. Therefore, this study aimed to examine the impact of comorbid SUDs on the risk of 11 somatic disease categories in patients with anorexia nervosa (AN), bulimia nervosa (BN) and unspecified eating disorder (USED) compared to matched controls. METHODS: A retrospective cohort study was conducted using Danish nationwide registries. The study population included 20 759 patients with EDs and 83 036 controls matched on month and year of birth, sex and ethnicity. Hazard ratios (HRs) were calculated to compare the risk of being diagnosed with a somatic disease (within 11 categories defined by the ICD-10) following first ED diagnosis (index date) between ED patients and controls both with and without SUDs (alcohol, cannabis or hard drugs). RESULTS: The ED cohort and matched controls were followed for 227 538 and 939 628 person-years, respectively. For ED patients with SUDs, the risk pattern for being diagnosed with different somatic diseases (relative to controls without SUDs) varied according to type of ED and SUD [adjusted HRs ranged from 0.95 (99% CI = 0.57; 1.59) to 4.17 (2.68, 6.47)]. The risk estimates observed among ED patients with SUDs were generally higher than those observed among ED patients without SUDs [adjusted HRs ranged from 1.08 (99% CI = 0.95, 1.22) to 2.56 (2.31, 2.84)]. Abuse of alcohol only had a non-synergistic effect on six disease categories in AN patients and five in BN and USED patients. Abuse of cannabis (with/without alcohol) had a non-synergistic effect on five disease categories in AN and BN patients and two in USED patients. Abuse of hard drugs (with/without alcohol or cannabis) had a non-synergistic effect on nine disease categories in AN patients, eight in BN patients and seven in USED patients. CONCLUSIONS: The present study documents non-synergistic but not synergistic harmful somatic consequences of SUDs among patients with different EDs, with AN and hard drugs being the most predominant factors. Hence, EDs and SUDs did not interact and result in greater somatic disease risk than that caused by the independent effects. Since EDs and SUDs have independent effects on many somatic diseases, it is important to monitor and treat ED patients for SUD comorbidity to prevent exacerbated physical damage in this vulnerable population.

Engineering circular RNA for potent and stable translation in eukaryotic cells.

Messenger RNA (mRNA) has broad potential for application in biological systems. However, one fundamental limitation to its use is its relatively short half-life in biological systems. Here we develop exogenous circular RNA (circRNA) to extend the duration of protein expression from full-length RNA messages. First, we engineer a self-splicing intron to efficiently circularize a wide range of RNAs up to 5 kb in length in vitro by rationally designing ubiquitous accessory sequences that aid in splicing. We maximize translation of functional protein from these circRNAs in eukaryotic cells, and we find that engineered circRNA purified by high performance liquid chromatography displays exceptional protein production qualities in terms of both quantity of protein produced and stability of production. This study pioneers the use of exogenous circRNA for robust and stable protein expression in eukaryotic cells and demonstrates that circRNA is a promising alternative to linear mRNA.