1. Bakare MO, Munir KM. {{Autism spectrum disorders (ASD) in Africa: a perspective}}. {Afr J Psychiatry (Johannesbg)}. 2011 Jul;14(3):208-10.
BACKGROUND: The universal occurrence of autism spectrum disorders (ASD) was queried about twenty-six years ago. It was thought to occur only in western industrialized countries with high technological development. Over the last decade, knowledge about ASD and its prevalence has been documented as being on the rise in different regions of the world, with most literature coming from the western world – the situation in Africa on aspects of ASD remain unclear. METHODS: Literature cited in Pubmed over the last decade on aspects of epidemiology, diagnosis, aetiology and knowledge of ASD in the African context were assessed. Keywords: autism, diagnosis, aetiology, knowledge and Africa were variously combined in the literature search. RESULTS: No study specifically addressed the epidemiology of ASD in Africa. One of the two studies that were relevant addressed epidemiology of ASD in Arab countries, though included two Northern African countries. A higher proportion of non-verbal cases of ASD compared to verbal cases was documented in literature coming from Africa. Associated co-morbid disorders included intellectual disability, epilepsy and oculo-cutaneous albinism. Aetiological factors postulated included post-encephalitic infection, genetic and auto-immune factors, and vitamin D deficiency. Knowledge about ASD in Africa was noted to be low. CONCLUSION: There is a need for epidemiological studies in Africa to define the magnitude of the problem of ASD and the characteristics of children affected by ASD in this region. This would help in planning and might be helpful in answering the question of aetiology of ASD. Policy making needs to be directed at issues of childhood developmental disorders in Africa.
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2. Hall SS, Lightbody AA, McCarthy BE, Parker KJ, Reiss AL. {{Effects of intranasal oxytocin on social anxiety in males with fragile X syndrome}}. {Psychoneuroendocrinology}. 2011 Aug 20.
Fragile X syndrome (FXS) is a rare inherited genetic disorder causing severe intellectual disability and autistic-like symptoms. Individuals with FXS, males in particular, often exhibit extreme eye gaze avoidance and hyperarousal when they encounter stressful social situations. We investigated whether oxytocin (OT), a hormone with prosocial and anxiolytic effects, could alleviate symptoms of social anxiety in this population. A randomized double-blind placebo-controlled single-dose trial was performed with intranasal administration of placebo, 24IU OT and 48IU OT. Measures of eye gaze frequency, heart rate, respiratory sinus arrhythmia (RSA), heart rate variability (HRV) and salivary cortisol were obtained during a structured social challenge conducted 50min following OT administration. Ten low-functioning males with FXS (aged 13-28 years) traveled to Stanford for the initial visit: 8 completed the study. Eye gaze frequency improved significantly in response to the 24IU OT dose and salivary cortisol levels decreased significantly in response to the 48IU OT dose. There was no effect of OT on heart rate, RSA or HRV although individual plots of the heart rate data suggested that OT increased heart rate in some participants and decreased heart rate in others. These findings suggest that intranasal administration of OT may ameliorate some symptoms of social anxiety in patients with FXS. Further double-blind placebo-controlled studies of OT, conducted in combination with behavioral treatment programs, may be warranted.
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3. Meng L, Lu L, Murphy KM, Yuede CM, Cheverud JM, Csernansky JG, et al. {{Neuroanatomic and behavioral traits for autistic disorders in age-specific restricted index selection mice}}. {Neuroscience}. 2011 Aug 25;189:215-22.
The pathogenesis of neurodevelopmental disorders such as autism is believed to be influenced by interactions between genetic and environmental factors, and appropriate animal models are needed to assess the influence of such factors on relevant neurodevelopmental phenotypes. A set of inbred mouse strains (Atchley strains) including A12 (E+L0) and A22 (E-L0) were generated by age-specific restricted index selection from a baseline random-bred ICR mouse population obtained from Harlan Sprague-Dawley [Atchley et al. (1997) Genetics 146(2):629-640; Indianapolis, IN, USA). As compared with the A22 strain, A12 mice had significantly increased early (P0-P10) body weight gain with minimal changes in late (P28-P56) body weight gain. We found that these strains also differed in brain weight, brain volume, cell proliferation, and FGF-2 levels in certain brain regions. Specifically, brain weight and volume were significantly greater in A12 mice than that in A22 mice at P10 and P28. Quantitative analysis of bromodeoxyuridine (BrdU) labeling of proliferating cells showed that the number of BrdU-positive cells in the A12 strain were significantly greater in the frontal cortex and lesser in the dentate gyrus than that in the A22 strain at P28. Western blot revealed that fibroblast growth factors-2 (FGF-2), but not brain-derived neurotrophic factor (BDNF), expression was significantly increased in the frontal cortex of A12 strain at P28. Also, A12 mice exhibited decreased intra-strain social interaction and increased repetitive stereotyped behaviors at P28. Our study suggests that A12 mice may partially mimic the anatomic and behavioral traits of patients with neurodevelopmental disorders such as autism spectrum disorders, and therefore may yield insights into the developmental mechanisms involved in their pathogenesis.
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4. Watson LR, Patten E, Baranek GT, Poe M, Boyd BA, Freuler A, et al. {{Differential Associations between Sensory Response Patterns and Language, Social, and Communication Measures in Children with Autism or Other Developmental Disabilities}}. {J Speech Lang Hear Res}. 2011 Aug 23.
PURPOSE: Examine patterns of sensory responsiveness (i.e., hyperresponsiveness, hyporesponsiveness, and sensory seeking) as factors that may account for variability in social-communicative symptoms of autism and variability in language, social, and communication skill development in children with autism or other developmental disabilities. METHOD: Children with autistic disorder (AD; n = 72, mean age = 52.3 months) and other developmental disabilities (DD; n = 44, mean age = 48.1 months) participated in a protocol measuring sensory response patterns, social-communicative symptoms of autism, and language, social, and communication skills. RESULTS: Hyporesponsiveness was positively associated with social-communicative symptom severity, with no significant group difference in the association. Hyperresponsiveness was not significantly associated with social-communicative symptom severity. A group difference emerged for sensory seeking and social-communicative symptom severity, with a positive association for the AD group only. For the two groups of children combined, hyporesponsiveness was negatively associated with language skills and social adaptive skills. Sensory seeking also was negatively associated with language skills. These associations did not differ between the two groups. CONCLUSIONS: Aberrant sensory processing may play an important role in the pathogenesis of autism and other developmental disabilities, as well as in the rate of acquisition of language, social, and communication skills.
