Recurrence of post-traumatic stress disorder: systematic review of definitions, prevalence and predictors.

BACKGROUND: Many people will experience a potentially traumatic event in their lifetime and a minority will go on to develop post-traumatic stress disorder (PTSD). A wealth of literature explores different trajectories of PTSD, focusing mostly on resilient, chronic, recovered and delayed-onset trajectories. Less is known about other potential trajectories such as recurring episodes of PTSD after initial recovery, and to date there has been no estimate of what percentage of those who initially recover from PTSD later go on to experience a recurrence. This systematic review aimed to synthesise existing literature to identify (i) how 'recurrence' of PTSD is defined in the literature; (ii) the prevalence of recurrent episodes of PTSD; and (iii) factors associated with recurrence. METHODS: A literature search of five electronic databases identified primary, quantitative studies relevant to the research aims. Reference lists of studies meeting pre-defined inclusion criteria were also hand-searched. Relevant data were extracted systematically from the included studies and results are reported narratively. RESULTS: Searches identified 5,398 studies, and 35 were deemed relevant to the aims of the review. Results showed there is little consensus in the terminology or definitions used to refer to recurrence of PTSD. Because recurrence was defined and measured in different ways across the literature, and prevalence rates were reported in numerous different ways, it was not possible to perform meta-analysis to estimate the prevalence of recurrence. We also found no consistent evidence regarding predictors of PTSD recurrence. CONCLUSION: A clear and consistent evidence-based definition of recurrence is urgently needed before the prevalence and predictors of recurrence can be truly understood.

Associations between community-level patterns of prenatal alcohol and tobacco exposure on brain structure in a non-clinical sample of 6-year-old children: a South African pilot study.

The current small study utilised prospective data collection of patterns of prenatal alcohol and tobacco exposure (PAE and PTE) to examine associations with structural brain outcomes in 6-year-olds and served as a pilot to determine the value of prospective data describing community-level patterns of PAE and PTE in a non-clinical sample of children. Participants from the Safe Passage Study in pregnancy were approached when their child was ∼6 years old and completed structural brain magnetic resonance imaging to examine with archived PAE and PTE data (n = 51 children-mother dyads). Linear regression was used to conduct whole-brain structural analyses, with false-discovery rate (FDR) correction, to examine: (a) main effects of PAE, PTE and their interaction; and (b) predictive potential of data that reflect patterns of PAE and PTE (e.g. quantity, frequency and timing (QFT)). Associations between PAE, PTE and their interaction with brain structural measures demonstrated unique profiles of cortical and subcortical alterations that were distinct between PAE only, PTE only and their interactive effects. Analyses examining associations between patterns of PAE and PTE (e.g. QFT) were able to significantly detect brain alterations (that survived FDR correction) in this small non-clinical sample of children. These findings support the hypothesis that considering QFT and co-exposures is important for identifying brain alterations following PAE and/or PTE in a small group of young children. Current results demonstrate that teratogenic outcomes on brain structure differ as a function PAE, PTE or their co-exposures, as well as the pattern (QFT) or exposure.

Juvenile idiopathic epilepsy in Arabian horses is not a single-gene disorder.

Valued for their temperament, beauty, athletic ability, and exhibition in the show ring, Arabian horses are an important component of the horse industry. Juvenile idiopathic epilepsy (JIE), a seizure disorder, is most often reported in Arabian foals from birth to 6 months of age. Affected foals exhibit tonic-clonic seizures lasting as long as 5 min and risking secondary complications like temporary blindness and disorientation. Some foals outgrow this condition, while others die or suffer lifelong complications if not treated. Previous work suggested a strong genetic component to JIE and proposed JIE to be a single-gene trait. In this work, we conducted a genome wide association study (GWAS) in 60 cases of JIE and 120 genetically matched controls, identifying loci suggesting JIE is not caused by a single locus. Coat color (chestnut, gray) phenotypes were used as positive control traits to assess the efficacy of GWAS in this population. Future work will attempt to future define candidate regions and explore a polygenic mode of inheritance.

Struggling, Forgotten, and Under Pressure: A Scoping Review of Experiences of Sex Workers During the COVID-19 Pandemic.

The COVID-19 pandemic profoundly affected physical, mental, and economic well-being across the globe and has disproportionately affected certain vulnerable groups. This paper provides a scoping review of literature on the impact of the COVID-19 pandemic on sex workers, published between December 2019 and December 2022. Six databases were systematically searched, identifying 1009 citations; 63 studies were included in the review. Thematic analysis revealed eight main themes: financial issues; exposure to harm; alternate ways of working; COVID-19 knowledge, protective behaviors, fear, and risk; well-being, mental health, and coping; access to support; access to health care; and the impact of COVID-19 on research with sex workers. COVID-associated restrictions led to reduced work and income, leaving many sex workers struggling to cover basic needs; additionally, government protections excluded those working in the informal economy. Fearing the loss of their already reduced number of clients, many felt compelled to compromise both prices and protective measures. Although some engaged in online sex work, this raised concerns about visibility and was impossible for those without technological access or skills. Many feared COVID-19, but felt pressure to continue working, often with clients who refused to wear masks or share exposure history. Other negative impacts on well-being related to the pandemic included reduced access to financial support or health care. Marginalized populations (and especially those in professions which require close contact like sex workers) need further support and capacity-building within the community to recover from the impact of COVID-19.

Ketamine treatment for refractory anxiety: A systematic review.

There is a growing interest in the psychiatric properties of the dissociative anaesthetic ketamine, as single doses have been shown to have fast-acting mood-enhancing and anxiolytic effects, which persist for up to a week after the main psychoactive symptoms have diminished. Therefore, ketamine poses potential beneficial effects in patients with refractory anxiety disorders, where other conventional anxiolytics have been ineffective. Ketamine is a noncompetitive antagonist of the N-methyl-d-aspartate (NMDA) glutamate receptor, which underlies its induction of pain relief and anaesthesia. However, the role of NMDA receptors in anxiety reduction is still relatively unknown. To fill this paucity in the literature, this systematic review assesses the evidence that ketamine significantly reduces refractory anxiety and discusses to what extent this may be mediated by NMDA receptor antagonism and other receptors. We highlight the temporary nature of the anxiolytic effects and discuss the high discrepancy among the study designs regarding many fundamental factors such as administration routes, complementary treatments and other treatments.

Correction: Mutations in MITF and PAX3 Cause "Splashed White" and Other White Spotting Phenotypes in Horses.

[This corrects the article DOI: 10.1371/journal.pgen.1002653.].

Phonological working memory is adversely affected in adults with anorexia nervosa: a systematic literature review.

PURPOSE: Cognitive restraint has potentiating and deleterious effects on working memory (WM) in anorexia nervosa (AN). Conflicting evidence may be due to heterogeneity of tasks examining different WM components (e.g., verbal/auditory versus visuospatial), and differences in adolescent versus adult AN. Additionally, differential cognitive profiles of restricting versus binge/purging subtypes, comorbid psychiatric disorders and psychotropic medication use may confound findings. METHODS: To address these conflicts, 25 studies, published between 2016 and 2021, investigating WM in children, adolescents and adults with AN were systematically reviewed using PRISMA guidelines. RESULTS: In 71% of WM tasks, no difference in performance between AN patients and age-matched controls was reported, while 29% of WM tasks showed worse performance. Adults with AN displayed deficits in 44% of the verbal/auditory tasks, while performance remained unaffected in 86% of visuospatial tasks. CONCLUSION: Examining age groups and WM subsystems separately revealed novel findings of differentially affected WM components in AN. Comorbidities and psychotropic medications were common among AN participants and should be regarded as critical confounding factors for WM measures. Future studies examining different components of WM, acknowledging these confounding factors, may reveal specific deficits in AN to aid treatment improvement strategies. LEVEL OF EVIDENCE: I, systematic review.

The psychological impact of quarantine and how to reduce it: rapid review of the evidence.

The December, 2019 coronavirus disease outbreak has seen many countries ask people who have potentially come into contact with the infection to isolate themselves at home or in a dedicated quarantine facility. Decisions on how to apply quarantine should be based on the best available evidence. We did a Review of the psychological impact of quarantine using three electronic databases. Of 3166 papers found, 24 are included in this Review. Most reviewed studies reported negative psychological effects including post-traumatic stress symptoms, confusion, and anger. Stressors included longer quarantine duration, infection fears, frustration, boredom, inadequate supplies, inadequate information, financial loss, and stigma. Some researchers have suggested long-lasting effects. In situations where quarantine is deemed necessary, officials should quarantine individuals for no longer than required, provide clear rationale for quarantine and information about protocols, and ensure sufficient supplies are provided. Appeals to altruism by reminding the public about the benefits of quarantine to wider society can be favourable.

Calculations on the Ruthenium-Catalyzed Diene and Dienyne Ring-Closing Metathesis Reactions in the Synthesis of Taxol Derivatives.

Density-functional and semiempirical calculations (M06, M06L, and PM6) on intermediates in the ring-closing metathesis (RCM) reactions in the synthesis of Taxol derivatives give results in excellent agreement with the results of previous experimental work. The results suggest that the degree of steric overloading plays a decisive role in determining the outcome (ene-ene or ene-yne-ene metathesis). Due to the rigidity of the Taxol skeleton being formed in the ene-yne-ene cascade reaction, the transition states in its final ene-ene metathesis reaction stage are particularly sensitive to steric effects. Thus, the reaction is predicted to be preferred for one diastereomer of the precursor in which the diol functionality is protected with a compact cyclic carbonate moiety, whereas the use of a bulkier benzoate-protecting group results in activation barriers for Taxol formation that are prohibitive. The reason why one diastereomer of the carbonate-protected precursor undergoes formation of a tricycle via an ene-yne-ene RCM cascade, whereas the other diastereomer undergoes cyclooctene formation via an ene-ene RCM, likely lies in the orientation of the pseudoaxial methyl group on the cyclohexene ring, which in the latter case would unfavorably point toward the reactive center of the Ru-complex, leading to Taxol formation.

Two Variants of KIT Causing White Patterning in Stock-Type Horses.

Over 30 polymorphisms in the KIT Proto-Oncogene Receptor Tyrosine Kinase (KIT) gene have been implicated in white spotting patterns ranging from small areas to full dermal depigmentation in the horse. We performed a candidate-gene exon sequencing approach on KIT and MITF, 2 known causatives of white spotting patterns, within 2 families of horses of unknown white spotting. Family 1 (Fam1, N = 5) consisted of a Quarter Horse stallion and 4 offspring with white spotting pattern ranging from legs, lower ventral, and head regions with jagged borders, to almost complete white. The second family (Fam2, N = 7) consisted of 6 half-sibling American Paint Horse/Quarter Horse and their dam, demonstrating unpigmented limbs with belly spots and an extensive white patterning on the face. This approach resulted in 2 variants significantly associated with familial phenotypes, where Fam1 variant is an indel leading to a frameshift mutation, and Fam2 a non-synonymous SNP. We validated the variants within an unrelated population of horses (Fam2 variant, P = 0.00271944) as well as for protein functional impact with ExPASy, Protter, Phyre2, SMART, PROVEAN, SIFT, and I-TASSER, confirming the reported associations. Fam1 associated variant, deemed W31, alters the protein sequence, leading to an early stop codon truncating the normal amino acid sequence from 972 to just 115 amino acids. Fam2 associated variant, deemed W32, may have a subtle impact on receptor function or could be in linkage with a non-coding or regulatory change creating the mild spotting pattern observed in this family.

GWAS Identifies a Region Containing the SALL1 Gene in Variation of Pigmentation Intensity Within the Chestnut Coat Color of Horses.

Chestnut coat color in horses is determined by a missense mutation within the MC1R gene. However, the intensity of the chestnut color can vary widely within individuals possessing this genotype. Here, we investigated this variation using standardized photographs of 96 horses. Each horse was ranked lightest to darkest within the cohort for phenotype by 3 blinded observers. A genome-wide association study utilizing the relative shade ranking as the phenotype and using 268 487 single-nucleotide polymorphisms (SNPs) genotyped using the Affymetrix Equine 670k array identified a single significantly associated region on chromosome 3 (P = 2.934 × 10-8). Analysis of whole-genome sequences for horses spanning the diverse range of chestnut color identified candidate SNPs within the coding sequence of the only gene in the region: SALL1. The function of SALL1 is largely unknown, though it is predicted to interact with the Hermansky-Pudlak Syndrome type 1 (HPS1) protein, which causes partial albinism in humans. However, with only one study suggesting a circumstantial influence of the SALL1 protein on pigmentation, additional work is needed to confirm this new coat color locus in larger populations and investigate the function of this protein for impacts on equine health.

Genetic Background of the Polish Primitive Horse (Konik) Coat Color Variation-New Insight into Dun Dilution Phenotypic Effect.

Only the blue dun coat color, produced by the action of the dun allele on the background of a black base coat, is officially permitted in the Polish primitive horse (PPH, Konik) breed, yet the population is not visually homogenous and various coat color shades occur. Herein, the molecular background of PPH coat color was studied based on genotyping of known causative variants in equine coat color-related genes (ASIP, MC1R, TBX3, SLC36A1, SLC45A2, PMEL17, and RALY). Additionally, screening for the new polymorphisms was conducted for the ASIP gene coding sequence and the TBX3 1.6-kb insert (associated with the dun dilution). We did not observe the champagne, silver, or cream color dilution variants in the PPH breed. A significant association (P < 0.01) was recorded for the genotype in TBX3 gene 1.6 kb in/del and the degree of dun coat dilution, demonstrating that the dominant action of the dun mutation is not fully penetrant. In addition to the effect of the 1.6 kb in/del zygosity, variants within the TBX3 insert were significantly associated with PPH coat color variability (P < 0.01), suggesting the presence of an additional allele at this locus. Finally, we identified a high frequency (35%) of genetically bay dun-colored PPH individuals that are officially recorded as blue (black base coat) duns. We propose that the difficulty in distinguishing these 2 phenotypes visually is due to an independent locus upstream of the ASIP gene, which was recently described as darkening the typical bay pigmentation shade.

Prevalence of Normal Weight Obesity and Health Risk Factors for the Female Collegiate Dancer.

ABSTRACT: Brown, AF, Alfiero, CJ, Brooks, SJ, Kviatkovsky, SA, Smith-Ryan, AE, and Ormsbee, MJ. Prevalence of normal weight obesity and health risk factors for the female collegiate dancer. J Strength Cond Res 35(8): 2321-2326, 2021-The purpose of this study was to investigate the prevalence of normal weight obesity (NWO) and evaluate the relationship between NWO and health risk factors in a collegiate dancer population. Reanalysis of data of female dancers (N = 42) from 2 larger studies was used to assess prevalence and health risk factors of NWO. Dancers completed a dual-energy x-ray absorptiometry scan to assess fat mass (FM), lean mass (LM), and visceral adipose tissue (VAT) and a 3-day food record. Normal weight obesity was defined as a body mass index (BMI) of 18.5-24.9 kg·m-2 and body fat (BF) ≥30%. Twenty-five (60%) dancers were classified as normal weight lean (NWL), and 17 dancers (40%) were classified as NWO. Significant differences were observed for BMI (NWL: 21.1 ± 1.7, NWO: 23.1 ± 1.6, p < 0.001), LM (NWL: 71.0 ± 2.9%, NWO: 62.5 ± 2.7%, p < 0.001), %BF (NWL: 24.8 ± 3.1%, NWO: 33.9 ± 2.6%, p < 0.001), and VAT (NWL: 130.6 ± 43.0 g, NWO: 232.3 ± 70.8 g, p < 0.001) between NWL and NWO. A significant difference was observed for carbohydrate intake (NWL: 4.7 ± 1.8 g·kg-1, NWO: 3.7 ± 1.0 g·kg-1, p = 0.020) between groups. Significant positive correlations with FM were observed between carbohydrate (kcal, p = 0.048), fat (kcal, p = 0.018; g·kg-1, p = 0.040), and total calories (p = 0.019) in NWO. Normal weight obesity in collegiate dancers may be more prevalent than previously perceived and may be significantly related to important health risk factors. The current study demonstrates the need for body composition assessments and emphasizing on promoting overall health in collegiate dancers.

Neural correlates of maintenance working memory, as well as relevant structural qualities, are associated with earlier antiretroviral treatment initiation in vertically transmitted HIV.

There is evidence of HIV affecting cognitive functioning across age groups, with adult studies showing related deficits in frontostriatal and hippocampal regional activity. Additionally, delayed initiation of antiretroviral treatment (ART) has been associated with poorer cognitive outcomes in HIV-infected youth. Little is known, however, of the neural correlates underlying such cognitive deficits in youth populations. We investigated maintenance working memory-related brain activity in South African HIV-infected youth and controls, and the effect of ART initiation age on underlying structures. Sixty-four perinatally infected youth (ages 9-12) and 20 controls (ages 9-13) underwent functional magnetic resonance imaging (fMRI) while completing 1-back and 0-back blocks of the N-back task. At an uncorrected p value threshold of 0.001, the HIV-infected group showed decreased activation in the left superior temporal gyrus, pre- and postcentral gyri, insula, and putamen as well as bilateral hippocampus, and mid cingulum. The HIV patients with delayed ART initiation showed less activation during processing conditions in the mid cingulum; left inferior parietal gyrus; and right inferior frontal, bilateral thalamic, and superior temporal regions. When these regions were tested for structural differences, the mid cingulum and right inferior frontal gyrus, insula, and thalamus were found to have less cortical thickness, surface area, or volume in the group with delayed ART initiation. Regional differences between HIV-infected youth and controls noted in the N-back task are consistent with impairments in structures involved in maintenance working memory. These data support earlier ART initiation in perinatally infected individuals.

Interactive impact of childhood maltreatment, depression, and age on cortical brain structure: mega-analytic findings from a large multi-site cohort.

BACKGROUND: Childhood maltreatment (CM) plays an important role in the development of major depressive disorder (MDD). The aim of this study was to examine whether CM severity and type are associated with MDD-related brain alterations, and how they interact with sex and age. METHODS: Within the ENIGMA-MDD network, severity and subtypes of CM using the Childhood Trauma Questionnaire were assessed and structural magnetic resonance imaging data from patients with MDD and healthy controls were analyzed in a mega-analysis comprising a total of 3872 participants aged between 13 and 89 years. Cortical thickness and surface area were extracted at each site using FreeSurfer. RESULTS: CM severity was associated with reduced cortical thickness in the banks of the superior temporal sulcus and supramarginal gyrus as well as with reduced surface area of the middle temporal lobe. Participants reporting both childhood neglect and abuse had a lower cortical thickness in the inferior parietal lobe, middle temporal lobe, and precuneus compared to participants not exposed to CM. In males only, regardless of diagnosis, CM severity was associated with higher cortical thickness of the rostral anterior cingulate cortex. Finally, a significant interaction between CM and age in predicting thickness was seen across several prefrontal, temporal, and temporo-parietal regions. CONCLUSIONS: Severity and type of CM may impact cortical thickness and surface area. Importantly, CM may influence age-dependent brain maturation, particularly in regions related to the default mode network, perception, and theory of mind.

A systematic review of factors affecting adherence to malaria chemoprophylaxis amongst travellers from non-endemic countries.

BACKGROUND: The aim of this systematic review was to identify predictors of actual or intended adherence with malaria chemoprophylaxis amongst travellers from non-endemic countries visiting endemic countries. METHODS: A systematic review of the literature was conducted using MEDLINE, Embase, PsycINFO and Global Health databases for studies published up to April 2019. Studies were included if they assessed reasons for adherence among people travelling from a country where malaria was not endemic to a country where it was. RESULTS: Thirty-two studies were included. Predictors of adherence were categorized as relating to either the nature of the travel or the traveller themselves. The three main predictors associated with nature of travel included: destination (e.g. country visited, urban vs rural areas), length of travel and type of travel (e.g. package vs backpacking holiday). The four main traveller-associated predictors were: age, reason for travel (e.g. business, leisure or visiting friends and relatives), perceived risk of catching malaria and experienced or expected medication effects. CONCLUSIONS: In order to improve adherence, clinicians should focus on travellers who are least likely to exhibit adherent behaviour. This includes travellers visiting destinations known to have lower adherence figures (such as rural areas), backpackers, business travellers, younger travellers and those travelling for longer periods of time. They should also check to ensure travellers' perceptions of the risks of malaria are realistic. Where appropriate, misperceptions (such as believing that curing malaria is easier than taking prophylaxis or that travellers visiting relatives have some level of innate immunity) should be corrected. All travellers should be informed of the potential side-effects of medication and given guidance on why it is nonetheless beneficial to continue to take prophylaxis. Further research is required to test interventions to improve adherence.

Metabogenomics reveals four candidate regions involved in the pathophysiology of Equine Metabolic Syndrome.

An analogous condition to human metabolic syndrome, Equine Metabolic Syndrome (EMS) is defined by several clinical signs including obesity, hyperinsulinemia, and peripheral insulin dysregulation (ID). Affected horses may also exhibit hypertension, hyperlipemia and systemic inflammation. Measures of ID typically comprise the gold-standard for diagnosis in veterinary care. Yet, the dynamic nature of insulin homeostasis and complex procedures of typical assays make accurate quantification of ID and EMS challenging. This work aimed to investigate new strategies for identification of biochemical markers and correlated genes in EMS. To quantify EMS risk within this population, we utilized a composite score derived from nine common diagnostic variables. We applied a global liquid chromatography/mass spectroscopy approach (HPLC/MS) to whole plasma collected from 49 Arabian horses, resulting in 3392 high-confidence features and identification of putative metabolites in public databases. We performed a genome wide association analysis with genotypes from the 670k Affymetrix Equine SNP array utilizing EMS-correlated metabolites as phenotypes. We discovered four metabolite features significantly correlated with EMS score (P < 1.474 × 10-5). GWAs for these features results (P = 6.787 × 10-7, Bonferroni) identified four unique candidate regions (r2 > 0.4) containing 63 genes. Significant genomic markers capture 43.52% of the variation in the original EMS score phenotype. The identified genomic loci provide insight into the pathways controlling variation in EMS and the origin of genetic predisposition to the condition. Rapid, feasible and accurate diagnostic tools derived from metabogenomics can be translated into measurable benefits in the timeline and quality of preventative management practices to preserve health in horses.

The usefulness of pre-employment and pre-deployment psychological screening for disaster relief workers: a systematic review.

BACKGROUND: Individuals who conduct disaster relief work overseas are exposed to a variety of traumatic events that can cause distress and trigger psychological illnesses. Identification of which disaster relief workers may be at risk of experiencing psychological distress or mental health disorders is frequently carried out through pre-employment or pre-deployment psychological screening. The primary objective of our review was to assess the evidence for pre-employment and pre-deployment psychological screening of relief workers who work in disaster situations. We aimed to identify specific pre-employment and pre-deployment characteristics that predict impaired wellbeing of an individual following engaging in disaster-related work. METHODS: A combined list of search terms was composed relating to disaster-related occupations, screening methods, psychological disorders, and study design. The databases used were PsycINFO, MEDLINE, EMBASE, and GlobalHealth. We included studies that used cross-sectional or longitudinal study designs; were published in the English language in peer-reviewed academic journals; reported on the association between pre-employment and pre-deployment features and post-deployment psychological disorders or distress; considered any occupational groups responding to a specified, discrete crisis; and used at least one validated measure of distress or disorder. We extracted data on the author; year of publication; disaster description; country of study; study design; population sample; disorder(s) outcome and the measures used; and results. RESULTS: Sixty-two, high-quality studies were included in the review. Forty-one potential predictors were identified. Of these, only volunteer status and previous history of mental illness and life stressors emerged as reliable predictors of distress or disorder. CONCLUSION: The results suggest that whilst it is attractive to screen for pre-employment and pre-deployment indicators of resilience, the evidence base for doing so is weak. At best, this sort of screening can only weakly suggest vulnerability and at worst may result in discrimination. Until better evidence about its usefulness becomes available, employers should exercise caution over its use.

Subcortical surface morphometry in substance dependence: An ENIGMA addiction working group study.

While imaging studies have demonstrated volumetric differences in subcortical structures associated with dependence on various abused substances, findings to date have not been wholly consistent. Moreover, most studies have not compared brain morphology across those dependent on different substances of abuse to identify substance-specific and substance-general dependence effects. By pooling large multinational datasets from 33 imaging sites, this study examined subcortical surface morphology in 1628 nondependent controls and 2277 individuals with dependence on alcohol, nicotine, cocaine, methamphetamine, and/or cannabis. Subcortical structures were defined by FreeSurfer segmentation and converted to a mesh surface to extract two vertex-level metrics-the radial distance (RD) of the structure surface from a medial curve and the log of the Jacobian determinant (JD)-that, respectively, describe local thickness and surface area dilation/contraction. Mega-analyses were performed on measures of RD and JD to test for the main effect of substance dependence, controlling for age, sex, intracranial volume, and imaging site. Widespread differences between dependent users and nondependent controls were found across subcortical structures, driven primarily by users dependent on alcohol. Alcohol dependence was associated with localized lower RD and JD across most structures, with the strongest effects in the hippocampus, thalamus, putamen, and amygdala. Meanwhile, nicotine use was associated with greater RD and JD relative to nonsmokers in multiple regions, with the strongest effects in the bilateral hippocampus and right nucleus accumbens. By demonstrating subcortical morphological differences unique to alcohol and nicotine use, rather than dependence across all substances, results suggest substance-specific relationships with subcortical brain structures.

The impact of unplanned school closure on children's social contact: rapid evidence review.

BackgroundEmergency school closures are often used as public health interventions during infectious disease outbreaks to minimise the spread of infection. However, if children continue mixing with others outside the home during closures, the effect of these measures may be limited.AimThis review aimed to summarise existing literature on children's activities and contacts made outside the home during unplanned school closures.MethodsIn February 2020, we searched four databases, MEDLINE, PsycInfo, Embase and Web of Science, from inception to 5 February 2020 for papers published in English or Italian in peer-reviewed journals reporting on primary research exploring children's social activities during unplanned school closures. Main findings were extracted.ResultsA total of 3,343 citations were screened and 19 included in the review. Activities and social contacts appeared to decrease during closures, but contact remained common. All studies reported children leaving the home or being cared for by non-household members. There was some evidence that older child age (two studies) and parental disagreement (two studies) with closure were predictive of children leaving the home, and mixed evidence regarding the relationship between infection status and such. Parental agreement with closure was generally high, but some disagreed because of perceived low risk of infection and issues regarding childcare and financial impact.ConclusionEvidence suggests that many children continue to leave home and mix with others during school closures despite public health recommendations to avoid social contact. This review of behaviour during unplanned school closures could be used to improve infectious disease modelling.