Convergent neuroanatomical and behavioural evidence of an amygdala hypothesis of autism

In this study we report a convergence of behavioural and neuroanatomical evidence in support of an amygdala hypothesis of autism. We find that people with high-functioning autism (HFA) show neuropsychological profiles characteristic of the effects of amygdala damage, in particular selective impairment in the recognition of facial expressions of fear, perception of eye-gaze direction, and recognition memory for faces. Using quantitative magnetic resonance (MR) image analysis techniques, we find that the same individuals also show abnormalities of medial temporal lobe (MTL) brain structure, notably bilaterally enlarged amygdala volumes. These results combine to suggest that developmental malformation of the amygdala may underlie the social-cognitive impairments characteristic of HFA. This malformation may reflect incomplete neuronal pruning in early development.

Nucleotide-binding domain 1 of cystic fibrosis transmembrane conductance regulator production of a suitable protein for structural studies

Cystic fibrosis is caused by mutations in the gene encoding the cystic fibrosis transmembrane conductance regulator (CFTR). This protein belongs to the large ATP-binding cassette (ABC) family of transporters. Most patients with cystic fibrosis bear a mutation in the nucleotide-binding domain 1 (NBD1) of CFTR, which plays a key role in the activation of the channel function of CFTR. Determination of the three dimensional structure of NBD1 is essential to better understand its structure-function relationship, and relate it to the biological features of CFTR. In this paper, we report the first preparation of recombinant His-tagged NBD1, as a soluble, stable and isolated domain. The method avoids the use of renaturing processes or fusion constructs. ATPase activity assays show that the recombinant domain is functional. Using tryptophan intrinsic fluorescence, we point out that the local conformation, in the region of the most frequent mutation DeltaF508, could differ from that of the nucleotide-binding subunit of histidine permease, the only available ABC structure. We have undertaken three dimensional structure determination of NBD1, and the first two dimensional 15N-1H NMR spectra demonstrate that the domain is folded. The method should be applicable to the structural studies of NBD2 or of other NBDs from different ABC proteins of major biological interest, such as multidrug resistance protein 1 or multidrug resistance associated protein 1.

Relationships between symbolic play, functional play, verbal and non-verbal ability in young children

It is well established that certain aspects of play in young children are related to their emerging linguistic skills. The present study examined the relationships between functional play, symbolic play, non-verbal ability, and expressive and receptive language in normally developing children aged between 1 and 6 years using standardized assessment procedures, including a recently developed Test of Pretend Play (ToPP). When effects of chronological age were partialled out, symbolic play remained significantly correlated with both expressive and receptive language, but not with functional play or non-verbal ability; and functional play was only correlated significantly with expressive language. It is concluded that ToPP will provide practitioners with a useful way of assessing symbolic ability in children between the ages of 1 and 6 years, and will contribute to the assessment and diagnosis of a number of communication difficulties, and have implications for intervention.

Recall readiness in children with autism

When people are asked to learn information they need to judge when they have encoded the information accurately and will be able to retrieve it correctly. Making such a judgment is an aspect of metacognitive ability, and is referred to as "recall readiness." Previous researchers have not considered recall readiness in children with autism, therefore we asked matched groups of children with autism, children with mental retardation, and normally developing children (mean mental age: 7 years) to study several pictures of objects until they felt ready to recall all the objects without error. Their recall was then tested. The children with autism and the children with mental retardation had impaired recall readiness compared to the normally developing children. We discuss this result with reference to other research into the metacognitive abilities of children with autism.

Systems approach to childhood and adolescent obesity prevention and treatment in a managed care organization

OBJECTIVE

To outline an intervention approach to childhood and adolescent obesity prevention and treatment, that will systematically facilitate effective communication, provide long-term social support and access to resources, that may be accessed proactively or on demand. Furthermore, this approach operates in an environment that involves all critical parties: child/adolescent, family-unit, physician and allied health professionals. SYSTEMS THINKING APPROACH: The objective is to bring together all key stakeholders and consider the interrelationships among them as a common process. In a managed care setting, this may be accomplished by optimizing the contributions of care delivery, health promotion and information systems.

SETTING

A not-for-profit, community governed Managed Care Organization (MCO) in the Midwestern United States. Telephone-based, centralized services facilitate a process of access, communication, documentation and intervention implementation.

CASE STUDIES

Two case studies are presented as examples of how access is obtained, the intervention is tailored to individual needs, communication is established, documentation is organized and long-term support is facilitated.

CONCLUSIONS

A systems thinking approach to obesity prevention and treatment in youth has great potential. In a MCO setting, such an approach may be implemented, since integrated health care delivery systems may allow a common process to be established that can bring together all key stakeholders.

Metamemory in children with autism

Five experiments are reported comparing metamemory abilities in children with autism, age- and language-matched mentally retarded children, and language-matched young normal controls. The mean language age of the participants in Experiment 1 was approximately 6 years, in Experiments 2, 3, and 4 approximately 8 years, and in Experiment 5 approximately 9 years. All the children were given one or more false belief tests. Experiment 1 assessed the children's understanding that a task variable (list length) and a person variable (age) will affect their own and others' performances on an immediate auditory-verbal recall task. Experiment 2 assessed the ability to utilize category cues in a picture recall task. Experiments 3 and 4 assessed the ability to verbalize strategies used in a memory span test and in one retrospective and two prospective memory situations. Experiment 5 assessed the children's knowledge and understanding of another person's memory. On the basis of available evidence and theory, we predicted that the children with autism would be impaired on all the metamemory tasks and that impairment would be associated with failure on tests of false belief. Our predictions were not supported. The children with autism were not impaired on any of the metamemory tasks, although they were less likely than controls to make spontaneous use of memory strategies involving other people. Unexpectedly few of the children failed the false belief tasks. These results are discussed in relation to theories concerning primary psychological deficits underlying autism.

Structural patterns in conversations with a woman who has autism

The experience of conversing with a person who has autism is often described as unsatisfactory. This article offers some suggestions as to why that might be. Conversation between an adult diagnosed as autistic and a researcher was transcribed and analyzed using the methodology of Conversation Analysis. The analysis highlights differences in conversational style between the two participants based on features such as topic movement, topic maintenance, repairs, interference from earlier structures and common collocations, overlaps, latching, and pauses. It is suggested that many of the features of the subject's talk which result in an overly repetitive style may be cognitively motivated.

Familiar face and voice matching and recognition in children with autism

Relatively able children with autism were compared with age- and language-matched controls on assessments of (1) familiar voice-face identity matching, (2) familiar face recognition, and (3) familiar voice recognition. The faces and voices of individuals at the children's schools were used as stimuli. The experimental group were impaired relative to the controls on all three tasks. Face recognition and voice recognition correlated significantly with voice-face identity matching, but not with each other, suggesting that the recognition impairments jointly cause the matching impairment. Neither chronological age nor verbal mental age were consistently related to the recognition and matching impairments.

Source monitoring by children with autism

The term "source monitoring" refers to the ability to distinguish the origins of memories. One type of source monitoring is reality monitoring-which means distinguishing internally and externally generated memories. This experiment examined reality monitoring by children with autism (with a mean mental age of 7 years 8 months). The children said several words and listened to another person say similar words. The children were then given a surprise memory test and asked to identify which words they had said and which the other person had said. The children with autism were compared to matched groups of normal children and children with mental retardation. There were no differences between the groups and, at least for this task, there was no evidence that children with autism have a deficit in their reality monitoring abilities.

Rhythm and language in children with moderate learning difficulties

The relationship between rhythmic ability, syllabic structure in the production of single words and two-word phrases, and overall language ability was assessed in a group of 22 children, aged between 4;0-8;0, with moderate learning difficulties in the absence of gross sensory, motor or behavioural difficulties. It was predicted that rhythmic ability would correlate significantly both with syllable production and with overall language attainment. We further predicted that clapping to highlight syllable number and rhythm would significantly improve syllable production. The first hypothesis was supported in so far as rhythmic ability correlated significantly with syllable production. However, rhythmic ability did not correlate significantly with overall language attainment. The second hypothesis was supported. The results are discussed in terms of their theoretical implications for our understanding of language development in children with moderate learning difficulties and in terms of their practical implications for therapy.

Interstrain variations in the cytomegalovirus (CMV) glycoprotein B gene sequence among CMV-infected children attending six day care centers

Using the shell vial assay and sequence analysis of a variable region of the glycoprotein B (gB) gene, cytomegalovirus (CMV) excretion rates in urine and virus transmission were studied among 93 children from six day care centers (DCCs). During a 6-month period, excretion rates differed significantly between DCCs (P < .001). The 6 gB gene sequences, obtained from 24 CMV-infected children, were classified in four previously defined groups. In five DCCs, 2 or 3 strains cocirculated, and none was dominant. Infection could have been acquired outside the DCC for 2 children and inside it for 9. Two children from the same DCC had mixed infections. No differences in hygiene, child care practices, or experience and level of qualification of the staff could explain this wide variety of excretion rates between DCCs. The distribution of gB gene patterns observed does not suggest that 1 type was dominant or more efficiently transmitted.

[Trial of prevention of severe Haemophilus influenzae type b infections and trial of tolerance, after PRP-T vaccination, in the Val-de-Marne region]

BACKGROUND

Protein-polysaccharide conjugate H influenzae vaccine is now routinely recommended for infants. To assess the vaccine's protective efficacy against invasive H influenzae infections and its safety, we conducted a study in the Val-de-Marne area of France.

METHODS

From April 1991 to April 1993, 22,443 children less than 5 years of age were given PRP-T vaccine. Infants less than 6 months were given three doses whereas those between 6 and 12 months received only two doses, and children over 1 year of age received one dose. According to the infant's DTP-IPV vaccination status, PRP-T was administered alone or reconstituted extemporaneously with DTP-IPV. The immunogenicity of the conjugate vaccine was assessed after three doses in 100 infants under the age of 6 months.

RESULTS

The PRP-T vaccine administered alone was safe. The reactions were more frequent when PRP-T vaccine was combined with DTP-IPV vaccine but they were comparable in frequency and severity to those observed after DTP-IPV vaccination. Before 1992, 18 Hib infections were reported each year in the Val-de-Marne region. During the study, only three Hib infections were reported each year.

CONCLUSIONS

The fall in incidence of Hib infections, greater than expected, suggests a widespread immune effect of the vaccine, possibly due to a decrease in Hib nasopharyngeal carriage. The antibody titres to each component of vaccine were comparable to those observed in previous clinical infant studies.

Clinical analysis of a CAD/CAM system for custom seating: a comparison with hand-sculpting methods

A CAD/CAM system for manufacturing custom seating inserts was evaluated within a moderately to severely disabled population. Using the Otto Bock Shape System, 25 CAD/CAM seats were manufactured at a remote facility and compared to 9 seats manufactured using hard-sculpting techniques. Clinician and client questionnaires were completed for each seat to assess satisfaction, fitting/manufacturing times, and to collect demographic data. The CAD/CAM method was significantly better (p < 0.05) than the hand-sculpting method in terms of on-site fabrication time. No significant differences were found for initial fitting time, final fitting time, clinician insert rating, and client satisfaction. These results support the CAD/CAM method as an effective and clinically efficient technique for making custom wheelchair seats.

Cost-effectiveness evaluation of vaccination against Haemophilus influenzae invasive diseases in France

A cost-effectiveness analysis of a vaccination program against Haemophilus influenzae type b (Hib) was conducted using French epidemiological data. The vaccine would be added as a fifth valence to the tetravalent vaccines (DTCP) widely used in France. The permanent sequelae of the Hib invasive diseases which might be avoided by vaccination were weighted to determine Quality Adjusted Life Years gained. In a stable French population of 3,746,000 children aged < 5 years old (1990), and for a followup period of ten years, the cost-effectiveness ratio of such a program for the French national health insurance system would equal 54,084 FF per year of life added or 34,050 FF per QALY. The net cost of the program during that period would be 1.02 billion FF for the French national health insurance system and 920 million FF for patients' families. Comparison of these projections with available information supports, a posteriori, the decision of the French government to authorize the licensing of the pentavalent vaccine.

Generativity in the play of young people with autism

Examines the ability of young people with autism to generate ideas for play. Young people with autism, children with learning difficulties, and younger normal children were asked to generate 12 different actions and follow 12 instructions with a car and a doll. The young people with autism were impaired, relative to the controls, at generating original actions with the car, but were as able as the controls to follow the instructions. However, the young people with autism were not impaired at generating original actions with the doll. All three groups produced similar amounts of symbolic play. Possible explanations for the difference in results for the two toys are discussed.

Executive function deficits and the pretend play of children with autism: a research note

The failure to produce pretend play seen in autism may arise from executive deficits associated with the syndrome. This experiment investigated the ability of children with autism to use various objects in pretence, the prediction being that they would have particular difficulty using props with a clear function (e.g. a pencil) to perform a different pretend function (e.g. to act as a toothbrush). However, children with autism were as likely as controls to select a prop with an inappropriate function from amongst other, nonfunctional props, suggesting that executive deficits of this particular kind cannot readily explain an absence of pretend play in autism.

Comprehension of pretense in children with autism

In an attempt to tap underlying competencies, the ability of children with autism to comprehend pretend acts carried out by an experimenter was compared with that shown by controls. These acts consisted of the pouring of a pretend substance from an appropriate container onto a target figure. There was no significant difference in the groups' ability to identify the pretend substance involved, to predict the pretend outcome of the actions, or to reflect on the pretend nature of the episodes. However, the performance of controls on these latter two tasks was surprisingly poor, limiting the implications that might be drawn from the observed absence of group differences in comprehension abilities.

Validational data on the Warwick Symbolic Play Test

This paper examines the validity of a recently developed test of symbolic play. The Warwick Symbolic Play Test (WSPT) was administered to 60 normal children, 30 girls and 30 boys aged 3-6 years. In addition the children's expressive and receptive language skills were assessed using the Renfrew Action Picture Test and the British Picture Vocabulary Scale respectively. Significant correlations were found between scores obtained on the play test and both language measures. Exploratory statistics indicated that, when age was taken into account, partial correlations between play and language remained moderate. Further analysis of the results also suggested that the relationship between play and language ability as measured by the tests was stronger for the younger children in the sample than for the older children. These results suggest that the WSPT may indeed be a useful assessment instrument, in conjunction with measures of functional play, for assessment of language ability, diagnosis and possible treatment of language disorders, especially for children under the developmental age of 5 years.

Symbolic play in autism: a review

Experimental research into the symbolic play of autistic children is reviewed in an attempt to outline the nature of their deficit in this area. While many studies can be criticized on methodological grounds, there is good evidence for an impairment in the spontaneous symbolic play of autistic children, an impairment that appears to extend to cover spontaneous functional play also. However studies that have investigated elicited and instructed play have indicated that autistic children may have a capacity for symbolic play that they do not spontaneously exhibit. The implications of these findings for various hypotheses concerning a symbolic play deficit in autism are considered and directions for future research are outlined.

Epidemiology of Haemophilus influenzae type b disease in France

Results are reported of an epidemiological study which spanned ten years and was carried out in two French departments. A total of 277 cases of Hib disease occurring in children < 5 years old are reported and, in this age group, the incidence is evaluated at 21/100,000. Meningitis accounted for 64% of infections and epiglottitis for 7%. While the overall mortality rate was 3.3%, death was secondary to meningitis in 7/8 cases. Sequelae, which were all related to meningitis, were major in 1.2% of cases, severe in 9% of cases, and involved some hearing loss in 3.3% of cases. The monitoring networks set up in the two departments were characterized by sensitivities of 87 and 94%, respectively. They should prove useful in assessing the impact of vaccination, when large-scale implementation of vaccination has spread to both departments.