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Item does not contain fulltext OBJECTIVE: The male preponderance in prevalence of autism is among the most pronounced sex ratios across neurodevelopmental conditions. The authors sought to elucidate the relationship between autism and typical sex-differential neuroanatomy, cognition, and related gene expression. METHODS: Using a novel deep learning framework trained to predict biological sex based on T(1)-weighted structural brain images, the authors compared sex prediction model performance across neurotypical and autistic males and females. Multiple large-scale data sets comprising T(1)-weighted MRI data were employed at four stages of the analysis pipeline: 1) pretraining, with the UK Biobank sample (>10,000 individuals); 2) transfer learning and validation, with the ABIDE data sets (1,412 individuals, 5-56 years of age); 3) test and discovery, with the EU-AIMS/AIMS-2-TRIALS LEAP data set (681 individuals, 6-30 years of age); and 4) specificity, with the NeuroIMAGE and ADHD200 data sets (887 individuals, 7-26 years of age). RESULTS: Across both ABIDE and LEAP, features positively predictive of neurotypical males were on average significantly more predictive of autistic males (ABIDE: Cohen's d=0.48; LEAP: Cohen's d=1.34). Features positively predictive of neurotypical females were on average significantly less predictive of autistic females (ABIDE: Cohen's d=1.25; LEAP: Cohen's d=1.29). These differences in sex prediction accuracy in autism were not observed in individuals with ADHD. In autistic females, the male-shifted neurophenotype was further associated with poorer social sensitivity and emotional face processing while also associated with gene expression patterns of midgestational cell types. CONCLUSIONS: The results demonstrate an increased resemblance in both autistic male and female individuals' neuroanatomy with male-characteristic patterns associated with typically sex-differential social cognitive features and related gene expression patterns. The findings hold promise for future research aimed at refining the quest for biological mechanisms underpinning the etiology of autism.

Background The effect of bacterobilia on morbidity after pancreatoduodenectomy remains unclear. The aim of this study was to examine the influence of positive intraoperative bile cultures and perioperative antibiotic prophylaxis on morbidity measured using the Comprehensive Complication Index, a weighted composite of postoperative complications. Methods Intraoperative bile cultures of 182 patients who underwent pancreatoduodenectomy were obtained. We examined the effect of intraoperative bile cultures and perioperative antibiotic prophylaxis on the Comprehensive Complication Index and the occurrence of postoperative complications. To this aim, we performed general linear models controlling for relevant demographic and perioperative factors. Results Positive (versus negative) intraoperative bile cultures were associated with a higher mean Comprehensive Complication Index (25.34 vs 16.81, P = .025). The mean Comprehensive Complication Index differed significantly between individuals with positive intraoperative bile cultures and bacterial strains not covered by perioperative antibiotic prophylaxis (26.2) versus positive intraoperative bile cultures and bacterial strains sensitive to perioperative antibiotic prophylaxis (22.7) (P = .045). Positive (versus negative) intraoperative bile cultures were associated with 4.75 times (95% confidence interval: 1.74–13.00, P = .002) greater odds of wound infections. The odds of wound infection were 1.93 times (95% confidence interval: .47–8.04) greater in those with positive intraoperative bile cultures and adequate perioperative antibiotic prophylaxis and 6.14 times (95% confidence interval: 2.17–17.35) greater in those with positive intraoperative bile cultures and inadequate perioperative antibiotic prophylaxis (versus negative intraoperative bile cultures) (P = .001). Conclusion Bacterobilia is associated with a significant increase in Comprehensive Complication Index and wound infections after pancreatoduodenectomy, which may be reduced by administration of a specific perioperative antibiotic prophylaxis. Acquisition of bile cultures sampled through the external conduit of patients with preoperative biliary drainage could help in selecting a specific perioperative antibiotic prophylaxis and patients with bile duct stents might benefit from broad spectrum perioperative antibiotic prophylaxis.

Contains fulltext : 248865.pdf (Publisher’s version ) (Closed access) OBJECTIVE: Autism spectrum disorder (ASD) is accompanied by highly individualized neuroanatomical deviations that potentially map onto distinct genotypes and clinical phenotypes. This study aimed to link differences in brain anatomy to specific biological pathways to pave the way toward targeted therapeutic interventions. METHODS: The authors examined neurodevelopmental differences in cortical thickness and their genomic underpinnings in a large and clinically diverse sample of 360 individuals with ASD and 279 typically developing control subjects (ages 6-30 years) within the EU-AIMS Longitudinal European Autism Project (LEAP). The authors also examined neurodevelopmental differences and their potential pathophysiological mechanisms between clinical ASD subgroups that differed in the severity and pattern of sensory features. RESULTS: In addition to significant between-group differences in "core" ASD brain regions (i.e., fronto-temporal and cingulate regions), individuals with ASD manifested as neuroanatomical outliers within the neurotypical cortical thickness range in a wider neural system, which was enriched for genes known to be implicated in ASD on the genetic and/or transcriptomic level. Within these regions, the individuals' total (i.e., accumulated) degree of neuroanatomical atypicality was significantly correlated with higher polygenic scores for ASD and other psychiatric conditions, and it scaled with measures of symptom severity. Differences in cortical thickness deviations were also associated with distinct sensory subgroups, especially in brain regions expressing genes involved in excitatory rather than inhibitory neurotransmission. CONCLUSIONS: The study findings corroborate the link between macroscopic differences in brain anatomy and the molecular mechanisms underpinning heterogeneity in ASD, and provide future targets for stratification and subtyping.

Differences in GABAergic function are critical to autistic visual sensory neurobiology and can be modulated by targeting GABA B .

Sensory atypicalities in autism spectrum disorder (ASD) are thought to arise at least partly from differences in γ-aminobutyric acid (GABA) receptor function. However, the evidence to date has been indirect, arising from correlational studies in patients and preclinical models. Here, we evaluated the role of GABA receptor directly, in 44 adults (

Circumstances surrounding the COVID-19 pandemic have resulted in significant personal and professional adjustments. Students and trainees, including those in autism research, face unique challenges to accomplishing their training and career goals during this unprecedented time. In this commentary, we, as members of the International Society for Autism Research Student and Trainee Committee, describe our personal experiences, which may or may not align with those of other students and trainees. Our experiences have varied both in terms of the ease (or lack thereof) with which we adapted and the degree to which we were supported in the transition to online research and clinical practice. We faced and continue to adjust to uncertainties about future training and academic positions, for which opportunities have been in decline and have subsequently negatively impacted our mental health. Students and trainees' prospects have been particularly impacted compared to more established researchers and faculty. In addition to the challenges we have faced, however, there have also been unexpected benefits in our training during the pandemic, which we describe here. We have learned new coping strategies which, we believe, have served us well. The overarching goal of this commentary is to describe these experiences and strategies in the hope that they will benefit the autism research community moving forward. Here, we provide a set of recommendations for faculty, especially mentors, to support students and trainees as well as strategies for students and trainees to bolster their self-advocacy, both of which we see as crucial for our future careers. LAY SUMMARY: The COVID-19 pandemic has affected students and trainees, including those in autism research, in different ways. Here, we describe our personal experiences. These experiences include challenges. For example, it has been difficult to move from in-person to online work. It has also been difficult to keep up with work and training goals. Moreover, working from home has made it hard to connect with our supervisors and mentors. As a result, many of us have felt unsure about how to make the best career choices. Working in clinical services and getting to know and support our patients online has also been challenging. Overall, the pandemic has made us feel more isolated and some of us have struggled to cope with that. On the other hand, our experiences have also included benefits. For example, by working online, we have been able to join meetings all over the world. Also, the pandemic has pushed us to learn new skills. Those include technical skills but also skills for well-being. Next, we describe our experiences of returning to work. Finally, we give recommendations for trainees and supervisors on how to support each other and to build a strong community.

Background Autism spectrum disorder (ASD) has a high cost to affected individuals and society, but treatments for core symptoms are lacking. To expand intervention options, it is crucial to gain a better understanding of potential treatment targets, and their engagement, in the brain. For instance, the striatum (caudate, putamen, and nucleus accumbens) plays a central role during development and its (atypical) functional connectivity (FC) may contribute to multiple ASD symptoms. We have previously shown, in the adult autistic and neurotypical brain, the non-intoxicating cannabinoid cannabidivarin (CBDV) alters the balance of striatal ‘excitatory–inhibitory’ metabolites, which help regulate FC, but the effects of CBDV on (atypical) striatal FC are unknown. Methods To examine this in a small pilot study, we acquired resting state functional magnetic resonance imaging data from 28 men (15 neurotypicals, 13 ASD) on two occasions in a repeated-measures, double-blind, placebo-controlled study. We then used a seed-based approach to (1) compare striatal FC between groups and (2) examine the effect of pharmacological probing (600 mg CBDV/matched placebo) on atypical striatal FC in ASD. Visits were separated by at least 13 days to allow for drug washout. Results Compared to the neurotypicals, ASD individuals had lower FC between the ventral striatum and frontal and pericentral regions (which have been associated with emotion, motor, and vision processing). Further, they had higher intra-striatal FC and higher putamenal FC with temporal regions involved in speech and language. In ASD, CBDV reduced hyperconnectivity to the neurotypical level. Limitations Our findings should be considered in light of several methodological aspects, in particular our participant group (restricted to male adults), which limits the generalizability of our findings to the wider and heterogeneous ASD population. Conclusion In conclusion, here we show atypical striatal FC with regions commonly associated with ASD symptoms. We further provide preliminary proof of concept that, in the adult autistic brain, acute CBDV administration can modulate atypical striatal circuitry towards neurotypical function. Future studies are required to determine whether modulation of striatal FC is associated with a change in ASD symptoms. Trial registration clinicaltrials.gov, Identifier: NCT03537950. Registered May 25th, 2018—Retrospectively registered, https://clinicaltrials.gov/ct2/show/NCT03537950?term=NCT03537950&draw=2&rank=1.

Background: The potential benefits of cannabis and its major non-intoxicating component cannabidiol (CBD) are attracting attention, including as a potential treatment in neurodevelopmental disorders such as autism spectrum disorder (ASD). However, the neural action of CBD, and its relevance to ASD, remains unclear. We and others have previously shown that response to drug challenge can be measured using functional magnetic resonance imaging (fMRI), but that pharmacological responsivity is atypical in ASD. Aims: We hypothesized that there would be a (different) fMRI response to CBD in ASD. Methods: To test this, task-free fMRI was acquired in 34 healthy men (half with ASD) following oral administration of 600 mg CBD or matched placebo (random order; double-blind administration). The ‘fractional amplitude of low-frequency fluctuations’ (fALFF) was measured across the whole brain, and, where CBD significantly altered fALFF, we tested if functional connectivity (FC) of those regions was also affected by CBD. Results: CBD significantly increased fALFF in the cerebellar vermis and the right fusiform gyrus. However, post-hoc within-group analyses revealed that this effect was primarily driven by the ASD group, with no significant change in controls. Within the ASD group only, CBD also significantly altered vermal FC with several of its subcortical (striatal) and cortical targets, but did not affect fusiform FC with other regions in either group. Conclusion: Our results suggest that, especially in ASD, CBD alters regional fALFF and FC in/between regions consistently implicated in ASD. Future studies should examine if this affects the complex behaviours these regions modulate.

Autism spectrum disorder (ASD) is a high cost neurodevelopmental condition; and there are currently no effective pharmacological treatments for its core symptoms. This has led some families and researchers to trial alternative remedies – including the non-intoxicating Cannabis sativa-derived compound cannabidivarin (CBDV). However, how CBDV affects the human brain is unknown. Previous (pre)clinical evidence suggests that CBDV may modulate brain excitatory-inhibitory systems, which are implicated in ASD. Hence, our main aim was to test, for the first time, if CBDV shifts glutamate and/or GABA metabolites – markers of the brain’s primary excitatory and inhibitory system - in both the ‘typical’ and autistic brain. Our subsidiary aim was to determine whether, within ASD, brain responsivity to CBDV challenge is related to baseline biological phenotype. We tested this using a repeated-measures, double-blind, randomized-order, cross-over design. We used magnetic resonance spectroscopy (MRS) to compare glutamate (Glx = glutamate + glutamine) and GABA + (GABA + macromolecules) levels following placebo (baseline) and 600 mg CBDV in 34 healthy men with (n = 17) and without (n = 17) ASD. Data acquisition from regions previously reliably linked to ASD (dorsomedial prefrontal cortex, DMPFC; left basal ganglia, BG) commenced 2 h (peak plasma levels) after placebo/CBDV administration. Where CBDV significantly shifted metabolite levels, we examined the relationship of this change with baseline metabolite levels. Test sessions were at least 13 days apart to ensure CBDV wash-out. CBDV significantly increased Glx in the BG of both groups. However, this impact was not uniform across individuals. In the ASD group, and not in the typically developing controls, the ‘shift’ in Glx correlated negatively with baseline Glx concentration. In contrast, CBDV had no significant impact on Glx in the DMPFC, or on GABA+ in either voxel in either group. Our findings suggest that, as measured by MRS, CBDV modulates the glutamate-GABA system in the BG but not in frontal regions. Moreover, there is individual variation in response depending on baseline biochemistry. Future studies should examine the effect of CBDV on behaviour and if the response to an acute dose of CBDV could predict a potential clinical treatment response in ASD.

Autism spectrum disorder (ASD) is a common, pervasive neurodevelopmental condition characterized by social impairments and restricted and repetitive behaviors and interests. Furthermore, frequently co-occurring physical and mental health conditions, including depression, anxiety, and epilepsy, contribute to the substantial burden on affected individuals, their family, and society. Consequently, the cost of ASD to society is greater than that of cancer, stroke, and heart disease combined. The cause of ASD is poorly understood, and there are currently no effective pharmacological treatments for its core symptoms. However, significant progress has been made in elucidating the molecular, genetic, neuroanatomical, and neurochemical associates of ASD, potentially paving the way for new treatment approaches.

There is increasing interest in the use of cannabis and its major non-intoxicating component cannabidiol (CBD) as a treatment for mental health and neurodevelopmental disorders, such as autism spectrum disorder (ASD). However, before launching large-scale clinical trials, a better understanding of the effects of CBD on brain would be desirable. Preclinical evidence suggests that one aspect of the polypharmacy of CBD is that it modulates brain excitatory glutamate and inhibitory γ-aminobutyric acid (GABA) levels, including in brain regions linked to ASD, such as the basal ganglia (BG) and the dorsomedial prefrontal cortex (DMPFC). However, differences in glutamate and GABA pathways in ASD mean that the response to CBD in people with and without ASD may be not be the same. To test whether CBD ‘shifts’ glutamate and GABA levels; and to examine potential differences in this response in ASD, we used magnetic resonance spectroscopy (MRS) to measure glutamate (Glx = glutamate + glutamine) and GABA+ (GABA + macromolecules) levels in 34 healthy men (17 neurotypicals, 17 ASD). Data acquisition commenced 2 h (peak plasma levels) after a single oral dose of 600 mg CBD or placebo. Test sessions were at least 13 days apart. Across groups, CBD increased subcortical, but decreased cortical, Glx. Across regions, CBD increased GABA+ in controls, but decreased GABA+ in ASD; the group difference in change in GABA + in the DMPFC was significant. Thus, CBD modulates glutamate-GABA systems, but prefrontal-GABA systems respond differently in ASD. Our results do not speak to the efficacy of CBD. Future studies should examine the effects of chronic administration on brain and behaviour, and whether acute brain changes predict longer-term response.

C-tactile (CT) afferents encode caress-like touch that supports social-emotional development, and stimulation of the CT system engages the insula and cortical circuitry involved in social-emotional processing. Very few neuroimaging studies have investigated the neural mechanisms of touch processing in people with autism spectrum disorder (ASD), who often exhibit atypical responses to touch. Using functional magnetic resonance imaging, we evaluated the hypothesis that children and adolescents with ASD would exhibit atypical brain responses to CT-targeted touch. Children and adolescents with ASD, relative to typically developing (TD) participants, exhibited reduced activity in response to CT-targeted (arm) versus non-CT-targeted (palm) touch in a network of brain regions known to be involved in social-emotional information processing including bilateral insula and insular operculum, the right posterior superior temporal sulcus, bilateral temporoparietal junction extending into the inferior parietal lobule, right fusiform gyrus, right amygdala, and bilateral ventrolateral prefrontal cortex including the inferior frontal and precentral gyri, suggesting atypical social brain hypoactivation. Individuals with ASD (vs. TD) showed an enhanced response to non-CT-targeted versus CT-targeted touch in the primary somatosensory cortex, suggesting atypical sensory cortical hyper-reactivity.