1. Baldassi S, Pei F, Megna N, Recupero G, Viespoli M, Igliozzi R, Tancredi R, Muratori F, Cioni G. {{Search superiority in autism within, but not outside the crowding regime}}. {Vision Res};2009 (Jun 11)
Visual cognition of observers with Autism Spectrum Disorder (ASD) seems to show an unbalance between the complementary functions of integration and segregation. This study uses visual search and crowding paradigms to probe the relative ability of children with autism, compared to normal developments children, to extract individual targets from cluttered backgrounds both within and outside the crowding regime. The data show that standard search follows the same pattern in the ASD and control groups with a strong effect of the set size that is substantially weakened by cueing the target location with a synchronous spatial cue. On the other hand, the crowding effect of 8 flankers surrounding a small peripheral target is virtually absent in the clinical sample, indicating a superior ability to segregate cluttered visual items. This data, along with evidence of an impairment to the neural system for binding contours in ASD, bring additional support to the general idea of a shift of the trade-off between integration and segregation toward the latter. More specifically, they show that when discriminability is balanced across conditions, an advantage in odd-man out tasks is evident in ASD observers only within the crowding regime, when binding mechanism might get compulsorily triggered in normal observers.
2. Grinker RR, Leventhal BL. Estimating {{the incidence of autism}}. {Epidemiology};2009 (Jul);20(4):622-623; author reply 623-624.
3. Hertz-Picciotto I, Delwiche L. {{Estimating the incidence of autism}}. {Epidemiology};2009 (Jul);20(4):623-624.
4. Kalb C. {Erasing autism}. {Newsweek};2009 (May 25);153(21):74-76.
5. Mazur-Kolecka B, Cohen IL, Jenkins EC, Flory M, Merz G, Ted Brown W, Frackowiak J. {{Sera from children with autism alter proliferation of human neuronal progenitor cells exposed to oxidation}}. {Neurotox Res};2009 (Jul);16(1):87-95.
Altered brain development during embryogenesis and early postnatal life has been hypothesized to be responsible for the abnormal behaviors of people with autism. The specific genetic background that alters vulnerability to some environmental insults has been suggested in the etiology of autism; however, the specific pathomechanisms have not been identified. Recently, we showed that sera from children with autism alter the maturation of human neuronal progenitor cells (NPCs) in culture. Results suggest that pre-programmed neurogenesis, i.e., neuronal proliferation, migration, differentiation, growth, and circuit organization, can be affected differently by factors present in autistic sera. In this report, we tested the effect of autistic sera on the vulnerability of NPCs to oxidative stress-a recognized risk factor of autism. We found that mild oxidative stress reduced proliferation of differentiating NPCs but not immature NPCs. This decrease of proliferation was less prominent in cultures treated with sera from children with autism than from age-matched controls. These results suggest that altered response of NPCs to oxidative stress may play a role in the etiology of autism.
6. Motil KJ, Morrissey M, Caeg E, Barrish JO, Glaze DG. {{Gastrostomy Placement Improves Height and Weight Gain in Girls With Rett Syndrome}}. {J Pediatr Gastroenterol Nutr};2009 (Jun 9)
BACKGROUND:: Growth failure and undernutrition complicate the clinical course of girls with Rett syndrome (RTT). These abnormalities are, in part, the consequence of oral motor dysfunction and inadequate dietary intake. OBJECTIVE:: To determine whether gastrostomy placement for nutritional therapy alters the natural history of growth failure and undernutrition in RTT. HYPOTHESIS:: We hypothesized that gastrostomy placement for nutritional therapy reverses the decline in height, weight, and body mass index (BMI) z scores in RTT. METHODS:: Standard stadiometric and anthropometric measures were obtained to derive height, weight, and BMI z scores and estimates of fat-free mass (FFM) and body fat in a cohort of girls (n = 92) with RTT before and after gastrostomy placement. Methyl-CpG-binding protein 2 (MECP2) mutations and the presence or absence of a fundoplication were recorded. RESULTS:: The differences in height (n = 73), weight (n = 81), and BMI (n = 81) z score slopes before and after gastrostomy placement were 1.31 + 2.06 (P < 0.001), 2.38 +/- 3.18 (P < 0.001), and 3.25 +/- 3.32 (P < 0.001), respectively. FFM and body fat (n = 43) increased after gastrostomy by 41 +/- 27 g/cm height (P < 0.001) and 7.5% +/- 5.7% body weight (P < 0.001), respectively. The differences in height, weight, and BMI z score slopes were similar regardless of the age at which the gastrostomy was placed. The differences in height, weight, and BMI z score slopes, as well as the change in FFM and body fat deposition after gastrostomy placement, did not differ between those who did or did not have a fundoplication and among the classes of MECP2 mutations. CONCLUSION:: Gastrostomy placement for aggressive nutritional therapy favorably altered the natural history of growth failure and undernutrition in RTT, but did not restore height and weight z scores to birth values, regardless of the age at which surgery occurred and in the presence or absence of a fundoplication.
7. Mrozek-Budzyn D, Kieltyka A, Majewska R. {{[Lack of association between MMR vaccination and the incidence of autism in children: a case-control study]}}. {Przegl Epidemiol};2009;63(1):107-112.Brak zwiazku miedzy szczepieniami skojarzona szczepionka przeciw odrze, swince i rozyczce (MMR) a wystepowaniem autyzmu u dzieci–wyniki badania kliniczno-kontrolnego.
The matched case-control study has been undertook to investigate whether measles, mumps, and rubella (MMR) vaccine may be casually associated with autism in children. Cases were children to 14-year old with diagnosis of core autism or atypical autism. Controls were matched on age, sex and general practice. The 96 cases and 192 controls were included. The study provides strong evidence against association of autism with both MMR and a single measles individual vaccine. Additionally children vaccinated with MMR, regardless of age of vaccination (to 18th, 24th and 36th month of life), had risk equal half of that of single measles vaccinated (for vaccinated to 18th month OR=0.41 95%PU: 0.20-0.85). Our findings confirm that MMR vaccination is not associated with an increased risk of autism in children.
8. Pei F, Baldassi S, Procida G, Igliozzi R, Tancredi R, Muratori F, Cioni G. {{Neural correlates of Texture and Contour Integration in children with Autism Spectrum Disorders}}. {Vision Res};2009 (Jun 10)
In this study, we have used an electrophysiological paradigm to investigate the neural correlates of the visual integration of local signals across space to generate global percepts in a group of low functioning autistic kids. We have analyzed the amplitude of key harmonics of the Visual Evoked Potentials (VEPs) recorded while participants observed orientation-based texture and contour stimuli, forming coherent global patterns, alternating with visual patterns in which the same number of local elements were randomly oriented in order to loose any globally organized feature. Comparing the results of the clinical sample with those obtained in an age-matched control group, we have observed that in the texture conditions the 1(st) and 3(rd) harmonics, containing signature of global form processing (Norcia et al., 2005), were present in the control group, while in the experimental group only the 1(st) harmonic was present. In the contour condition the 1(st) harmonic was not present for both groups while the 3(rd) harmonic was significantly present in the control group but absent in the group with autism. Moreover, the amount of organization required to elicit significant 1(st) harmonic response in the Texture condition was higher in the clinical group. The present results bring additional support to the idea that texture and contour processing are supported by independent mechanisms in normal vision. Autistic vision would thus be characterized by a preserved, perhaps weaker texture mechanism, possibly mediated by feedback interactions between visual areas, and by a disfunction of the mechanism supporting contour processing, possibly mediated by long-range intra-cortical connections. Within this framework, the residual ability to detect contours shown in psychophysical studies could be due to the contribution of the texture mechanism to contour processing.
9. Sizoo B, van den Brink W, van Eenige MG, van der Gaag RJ. {{Personality characteristics of adults with autism spectrum disorders or attention deficit hyperactivity disorder with and without substance use disorders}}. {J Nerv Ment Dis};2009 (Jun);197(6):450-454.
We examined temperament and character profiles of 128 adults with autism spectrum disorder (ASD) or attention deficit and hyperactivity disorder (ADHD). Participants completed the abbreviated Temperament and Character Inventory. The ASD and ADHD groups showed distinct temperament profiles (ADHD: high novelty seeking, ASD: low reward dependence, high harm avoidance) and low character scores in both groups. We then stratified ASD and ADHD into current substance use disorder (SUD+), former (SUD;), or no history of Substance Use Disorder (SUD-). Novelty seeking and reward dependence were only significantly lower for ASD/SUD-, but normal for ASD/SUD; and ASD/SUD+ subgroups. Persistence scores were highest in both SUD; subgroups. We concluded that temperament profiles of ASD and ADHD patients differ significantly, and are similar to profiles reported in earlier studies, but appear to depend on the SUD status. Surprisingly, normal social orientation is found in ASD patients with former or current SUD. High persistence scores characterize patients who overcome SUD.
10. Voituron N, Zanella S, Menuet C, Dutschmann M, Hilaire G. {{Early breathing defects after moderate hypoxia or hypercapnia in a mouse model of Rett Syndrome}}. {Respir Physiol Neurobiol};2009 (Jun 10)
Rett syndrome (RTT) is a rare neurodevelopmental disease caused by mutations in the transcriptional repressor methyl-CpG-binding protein 2 (MeCP2) and accompanied by complex symptoms, including erratic breathing and life-threatening apnoeas. In Mecp2-deficient male mice (Mecp2(-/y)), breathing is normal at birth but becomes altered after postnatal day 30 (P30), with erratic rhythm and apnoeas aggravating until death at around P60. Using plethysmography, we analyzed breathing of unrestrained wild type mice and Mecp2(-/y) at P15, P25 and P30 under air and under short lasting exposure to moderate hypoxia or hypercapnia. In Mecp2(-/y) with normal resting ventilation, we report exacerbated respiratory responses to hypoxia at P30 and transient apnoeas with erratic rhythm after hypoxia and hypercapnia at P30, P25 and occasionally P15. Then environmental factors may induce breathing defects well before than expected in Mecp2(-/y) and possibly in RTT patients. We therefore suggest avoiding exposure of young RTT patients to environmental situations where they may encounter moderate hypoxia or hypercapnia.
