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Neufeld, J.

Publications and source records attributed to Neufeld, J..

3 recordsLinked to original sources

Sex differences in brain structure: An autism twin study on restricted and repetitive behaviors

Females with autism spectrum disorder have been reported to exhibit fewer and less severe restricted and repetitive behaviors and interests compared to males. This difference might indicate sex specific alterations of brain networks involved in autism symptom domains, especially within cortico-striatal and sensory integration networks. This study used a well-controlled twin design to examine sex differences in brain anatomy in relation to repetitive behaviors. In 75 twin pairs (n=150, 62 females, 88 males) enriched for autism spectrum disorder (n=32), and other neurodevelopmental disorders (n =32), we explored the association of restricted and repetitive behaviors and interests - operationalized by the Autism Diagnostic Interview-Revised (C domain) and the Social Responsiveness Scale-2 (Restricted Interests and Repetitive Behavior subscale), with cortical volume, surface area and thickness of neocortical, sub-cortical and cerebellar networks. Cotwin control analyses revealed within-pair associations between RRBI symptoms and the right intraparietal sulcus and right orbital gyrus in females only. These findings endorse the importance of investigating sex differences in the neurobiology of autism symptoms, and indicate different etiological pathways underlying restricted and repetitive behaviors and interests in females and males.

neuroscience

Sex differences along the Autism Continuum: A twin study of brain structure

Females might possess protective mechanisms regarding autism spectrum disorder (ASD) and require a higher detrimental load, including structural brain alterations, before developing clinically relevant levels of autistic traits. This study examines sex differences in structural brain morphology in autism and autistic traits using a within-twin pair approach. Twin design inherently controls for shared confounders and enables the study of gene-independent neuroanatomical variation. N=148 twins (62 females) from 49 monozygotic and 25 dizygotic same-sex pairs were included. Participants were distributed along the whole continuum of autism including twin pairs discordant and concordant for clinical ASD. Regional brain volume, surface area and cortical thickness were computed. Within-twin pair increases in autistic traits were related to decreases in cortical volume and surface area of temporal and frontal regions specifically in female twin pairs, in particular regions involved in social communication, while only two regions were associated with autistic traits in males. The same pattern was detected in the monozygotic twin pairs only. Thus, non-shared environmental factors seem to impact female more than male cerebral architecture. Our results are in line with the hypothesis of a female protective effect in autism and highlights the need to study ASD in females separately from males.

neuroscience

Comprehensive skin microbiome analysis reveals the uniqueness of human-associated microbial communities among the class Mammalia

Skin is the largest organ of the body and represents the primary physical barrier between mammals and their external environment. The objective of this research was to generate a skin microbiota baseline for members of the class Mammalia, testing the effects of host species, geographic location, body region, and biological sex. The back, torso, and inner thigh regions of 177 non-human mammals were collected to include representatives from 38 species and 10 mammalian orders. Animals were collected from local farms, zoos, households, and the wild. All samples were amplified using the V3-V4 16S rRNA gene region and sequenced using a MiSeq (Illumina). For reference, previously published skin microbiome data from 20 human participants, sampled using an identical protocol to the non-human mammals, were included in the analysis. Human skin was significantly less diverse than all other mammalian orders and the factor most strongly associated with community variation for all samples was whether the host was a human. Within non-human samples, host taxonomic order was the most significant factor influencing the skin community, followed by the geographic location of the habitat. By comparing the congruence between known host phylogeny and microbial community dendrograms, we observed that Artiodactyla (even-toed ungulates) and Perissodactyla (odd-toed ungulates) had significant congruence, providing first evidence of phylosymbiosis between skin communities and their hosts.\n\nSignificanceSkin forms a critical protective barrier between a mammal and its external environment. Baseline data on the mammalian skin microbiome is crucial for making informed decisions related to veterinary research and biodiversity conservation strategies, in addition to providing insight into mammalian evolutionary history. To our knowledge, this study represents the largest mammalian skin microbiota project to date. These findings demonstrate that human skin is distinct, not only from other Primates, but from all 10 mammalian orders sampled. Using phylosymbiosis analysis, we provide the first evidence that co-evolution may be occurring between skin communities and their mammalian hosts, which warrants more in-depth future studies of the relationships between mammals and their skin microbiota.

microbiology