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P Tanguay

Publications and source records attributed to P Tanguay.

At least 19 recordsLinked to original sources
PubMed2006

A spontaneous albino mutant of Ceratocystis resinifera results from a point mutation in the polyketide synthase gene, PKS1.

We characterized a spontaneous albino mutant of Ceratocystis resinifera. Compared with the wild-type progenitor strain, the albino mutant had a reduced linear growth on culture medium, but its growth on lodgepole pine sapwood was unaffected. The albino mutant did not produce any coloured pigment on agar media or wood. However, upon exposure to exogenous scytalone, an intermediate metabolite of the melanin pathway, the production of a brownish melanin was restored. This suggests that the albino phenotype resulted from a mutation affecting the melanin synthesis pathway, upstream of the scytalone synthesis step. Melanin production was restored in the mutant by transforming it with a wild-type copy of the Ceratocystis resinifera polyketide synthase gene, PKS1. The complemented transformants produced melanin, indicating that the PKS1 gene was defective in the albino mutant. Sequence analysis revealed that the PKS1 allele found in the albino contained a single point mutation that resulted in an amino acid change from serine to proline at the 3' end of the beta-ketoacyl synthase motif.

Amino Acid Sequence↗
PubMed2001

Establishment of a gene transfer system for Pseudozyma flocculosa, an antagonistic fungus of powdery mildew fungi.

A reliable DNA-mediated transformation system has been developed for Pseudozyma flocculosa, a fungus that is antagonistic to powdery-mildew fungi. Plasmids harboring various selectable markers under the control of different promoters were tested. Molecular analyses demonstrated that successful transformation could be achieved using a plasmid that confers resistance to hygromycin B under the control of the Ustilago maydis hsp70 promoter and terminator sequences. On average, 1-40 (mean = 20) transformants were obtained per 10 microg of linearized DNA per 10(8) protoplasts. Southern analysis of the transformants revealed that, in each case, the vector had integrated in multiple tandem copies into the genome of P. flocculosa, and that integration events were random. Pulsed-field gel electrophoresis was employed to separate the genome of P. flocculosa into at least 11 chromosomes with sizes ranging from 0.55 Mb to 2.9 Mb. Hybridization with the plasmid indicated that integration of vector DNA had occurred in one to several chromosomes depending on the transformant examined.

Base Sequence↗
PubMed1999

Practice parameters for the assessment and treatment of children, adolescents, and adults with autism and other pervasive developmental disorders. American Academy of Child and Adolescent Psychiatry Working Group on Quality Issues.

Autism and the related pervasive developmental disorders are characterized by patterns of delay and deviance in the development of social, communicative, and cognitive skills, which arise in the first years of life. Although frequently associated with mental retardation, these conditions are distinctive in terms of their course and treatment. These conditions have a wide range of syndrome expression, and their management presents particular challenges for clinicians. Individuals with these conditions can present for clinical care at any point in development. The multiple developmental and behavioral problems associated with these conditions often require the care of multiple providers; coordination of services and advocacy for individuals and their families is important. Early, sustained intervention is indicated, as is the use of various treatment modalities (e.g., pharmacotherapy, special education, speech/communication therapy, and behavior modification).

Adolescent↗
PubMed1999

Summary of the Practice Parameters for the Assessment and Treatment of Children, Adolescents, and Adults with Autism and other Pervasive Developmental Disorders. American Academy of Child and Adolescent Psychiatry.

This summary provides an overview of the assessment and treatment recommendations contained in the Practice Parameters for the Assessment and Treatment of Children, Adolescents, and Adults With Autism and Other Pervasive Developmental Disorders. The parameters were written to aid clinicians in the assessment and treatment of children and adolescents with autism and other pervasive developmental disorders. Autism and the related pervasive developmental disorders are characterized by patterns of delay and deviance in the development of social, communicative, and cognitive skills, which arise in the first years of life. Although frequently associated with mental retardation, these conditions are distinctive in terms of their course and treatment. These conditions have a wide range of syndrome expression, and their management presents particular challenges for clinicians. Individuals with these conditions can present for clinical care at any point in development. The multiple developmental and behavioral problems associated with these conditions often require the care of multiple providers; coordination of services and advocacy for individuals and their families is important. Early, sustained intervention is indicated, as is the use of various treatment modalities (e.g., pharmacotherapy, special education, speech/communication therapy, and behavior modification.

Adolescent↗
PubMed1995

Autism, affective disorders, and social phobia.

The purpose of this study is to test the hypothesis that major affective and/or anxiety disorders are increased among relatives of autistic probands compared with controls. Among 36 families with an autistic child, 23 (64%) have a first degree relative diagnosed with major depressive disorder and 14 (39%) have a first degree relative diagnosed with social phobia. These rates are significantly greater than the 19% and 5%, respectively, found among 21 families with a child having a genetic condition, tuberous sclerosis complex, or a seizure disorder but no autism. The frequency of major depression among the 96 first degree relatives of autistic probands is 37.5% compared with 11.1% found among 45 relatives of control probands. The frequency of social phobia, 20.2%, is approximately 10 times more common than that found among the relatives of the control probands (2.4%). Elevated rates of both major depression and social phobia are found among parents and siblings in the families with an autistic child. Furthermore, 64% of parents affected with a major depression had the onset of the first depressive episode prior to the birth of the autistic child and all parents with social phobia had the onset of condition prior to the birth of the autistic child. Family patterns differ depending on the intellectual level of the autistic child; specifically, social phobia is significantly greater among the first degree relatives of non-retarded autistic probands than among relatives of individuals with autism and comorbid mental retardation.(ABSTRACT TRUNCATED AT 250 WORDS)

Autistic Disorder↗
PubMed1993

An intervention to improve the reliability of manuscript reviews for the Journal of the American Academy of Child and Adolescent Psychiatry.

OBJECTIVE: The effects of methods used to improve the interrater reliability of reviewers' ratings of manuscripts submitted to the Journal of the American Academy of Child and Adolescent Psychiatry were studied. METHOD: Reviewers' ratings of consecutive manuscripts submitted over approximately 1 year were first analyzed; 296 pairs of ratings were studied. Intraclass correlations and confidence intervals for the correlations were computed for the two main ratings by which reviewers quantified the quality of the article: a 1-10 overall quality rating and a recommendation for acceptance or rejection with four possibilities along that continuum. Modifications were then introduced, including a multi-item rating scale and two training manuals to accompany it. Over the next year, 272 more articles were rated, and reliabilities were computed for the new scale and for the scales previously used. RESULTS: The intraclass correlation of the most reliable rating before the intervention was 0.27; the reliability of the new rating procedure was 0.43. The difference between these two was significant. The reliability for the new rating scale was in the fair to good range, and it became even better when the ratings of the two reviewers were averaged and the reliability stepped up by the Spearman-Brown formula. The new rating scale had excellent internal consistency and correlated highly with other quality ratings. CONCLUSIONS: The data confirm that the reliability of ratings of scientific articles may be improved by increasing the number of rating scale points, eliciting ratings of separate, concrete items rather than a global judgment, using training manuals, and averaging the scores of multiple reviewers.

Algorithms↗
PubMed1993

Autistic children and the object permanence task.

Many mentally retarded autistic children can understand the concept of object permanence, but, in comparison to developmental-age matched normal children, the behavioral strategies they employ in carrying out the Casati-Lezine Object Permanence Test are deficient and lead to failure. These deficiencies appear unrelated to interference of stereotypic or other bizarre behavior in task performance. Similar problem-solving deficiencies can be found in mentally retarded children who are not autistic, suggesting that the deficiencies themselves are less related to the social-communication deficits of autistic children, but more to the general problem-solving difficulties found in children with a lower developmental quotient. Nevertheless, the qualitative analysis of results shows a tendency in autistic children, despite their better developmental level, to use less coordinated and regular sequences to solve the task than normal or mentally retarded children.

Attention↗
PubMed1992

Regional cerebral glucose metabolism and attention in adults with a history of childhood autism.

Sixteen high-functioning adults with a history of childhood autism and 26 normal control subjects underwent [18F]fluoro-2-deoxyglucose positron-emission tomography to assess regional cerebral glucose metabolic rate (GMR). Autistic patients had a left > right anterior rectal gyrus asymmetry, as opposed to the normal right > left asymmetry in that region. Patients also showed low GMR in the left posterior putamen and high GMR in the right posterior calcarine cortex. Brain regions with GMR > 3 SD from the normal mean were more prevalent in patients than in control subjects. This variable pattern of abnormal activity is consistent with heterogeneous neurophysiological etiology; group differences in striatum and cortex may represent a final common pathway.

Adolescent↗
PubMed1990

The Behavioral Summarized Evaluation: validity and reliability of a scale for the assessment of autistic behaviors.

The Behavioral Summarized Evaluation (BSE), is a 20-item paper-and-pencil rating scale specifically designed for the measurement of behavioral parameters which could be related to biological data in autistic children involved in educational programs, neurophysiological studies, and therapeutic trials. The development of the scale, the validity, and reliability studies are presented in this paper. The results suggest that the BSE is an acceptable tool for the assessment of autistic behaviors, easy to handle, and accessible to both professionals and paraprofessionals of the medico-educative staff. It is a useful addition to the bioclinical researcher's evaluation battery for bioclinical and therapeutic studies. However, more work is suggested to further investigate the psychometric properties of this behavior assessment instrument.

Adolescent↗
PubMed1989

Positron emission tomography of the cerebellum in autism.

On the basis of neurological evidence that autistic patients have fewer Purkinje and granule cells in the cerebellum as well as vermal cerebellar hypoplasia, the authors tested the hypothesis that autistic patients have cerebellar hypofunctioning. They used positron emission tomography of the cerebellum with 18F-labeled 2-deoxyglucose to study seven autistic patients and eight age-matched control subjects. The results showed no significant difference in mean cerebellar glucose metabolism between the two groups, but all mean glucose rates of the autistic patients were either equal to or greater than those of the control subjects. The implications of these findings are discussed.

Adult↗
PubMed1984

Are there sex differences in averaged evoked responses produced by coupling sound and light in children and adults?

Averaged evoked response (AER) amplitudes have been reported to be larger in women than in men. The aim of this study was to determine whether AER changes produced by coupling sound and light differed between males and females (adults and children). Given the 3:1 male-female ratio in early infantile autism, we reasoned that information about sex-related differences in normal subjects might be important in interpreting the results in autism. We observed the characteristic AER changes when coupling sound and light: increased response amplitude over the occiput for both adults and children, decreased response amplitude over the vertex for adults and N1 decreased and P2 increased response amplitude over the vertex for children. Differences appeared as a function of sex in adults: the number and the amplitudes of AERs recorded in women were greater than in men with the exception of the P2 peak recorded over the occiput which was similar for males and females. The sex-related differences observed in the number and amplitudes of AERs are reduced when coupling sound and light.

Acoustic Stimulation↗
PubMed1984

[Relation between auditory evoked potentials (presence, amplitude) during sound and light conditioning and levels of dopamine derivatives in infantile autism].

The aim of this study was to study the relationships between conditioned AEPs and homovanillic acid (HVA) levels in autistic children (A, 9 boys, average age 6.3) compared to normal children (9 boys, average age 6.5) and to mentally retarded children (MR, 9 boys, average age 6.1) without any autistic behavior. AEPs were recorded at Cz and Oz during two sessions. The auditory stimulus (S) was first presented alone (habituation); the visual stimulus (L) was then presented 800 msec after S (conditioning). S was again presented alone (extinction). Urinary HVA dosage was performed on samples of urine taken after a 48-h tyrosine-free diet. Conditioning induced enhancement of AEPs. Latencies and amplitudes were smaller in autistic children. AEP presence was smaller in patients than in normal children and smaller in MR than in A children. Urinary HVA level was higher in patients and higher in the MR group than in the A group. A negative correlation between HVA level and Cz AEP presence was observed. Results showing higher Cz AEP variability and higher HVA level in MR than in autistic children tend to lead us to consider that both syndromes are related to common neurological dysfunctionings rather than indicating autistic syndrome behavioral specificity.

Attention Deficit Disorder with Hyperactivity↗
PubMed1984

[Brain stem auditory evoked potentials in the normal and autistic child].

From a neurophysiological viewpoint a hypothesis for the etiology of early infantile autism suggests that the symptoms are a result of abnormalities in processing sensory input at the level of the brain-stem. The methods for recording auditory evoked responses (BAERs) seemed particularly well suited to study a failure at this level. BAERs to brief monaural and binaural stimulation were studied in 17 autistic children ranging in age from 3 to 9 years (mean = 6.1). They were age and sex matched to normal controls. Electrodes were placed at the vertex and at the mastoid ipsilateral to the stimulation. Signals were amplified 10(5) using an amplifier with bandpass filters set at 160 Hz and 3 kHz. Stimuli were clicks (120 microsec) delivered to subjects through earphones at 2 intensities: 70 and 90 dB. Stimuli were presented in blocks of 3000 clicks (1500 clicks for each intensity) with a rate of 10/sec. No sedative medication was used. There was no difference between autistic and normal children for the latencies of peak I. Latencies of peaks II, III, IV and V were found to be shorter in autistic than in normal children. The I-II and II-III interpeak transmission times were significantly decreased in the autistic group, but not III-V interpeak transmission time. Autistic children showed V-VN amplitude greater than normal children. Our findings suggest that in the autistic syndrome, there is a defect of the modulation processing input related to intensity at brain-stem level.

Autistic Disorder↗
PubMed1983

Parental reproductive problems and gestational hormonal exposure in autistic and schizophrenic children.

The incidence of infertility and two or more spontaneous abortions was significantly increased in the parents, compared to that reported for the general population, in this pilot survey of 61 patients evaluated for major childhood psychoses. In addition, 18% of our patients had a history of early gestational exposure to progesterone/estrogen compounds (9 patients) and to cortisone (2 patients). This frequency of gestational hormoné exposure was significantly increased over that in normal infants from three published surveys. However, in 5 of the 11 patients with gestational hormonal exposure, the medication was prescribed because of prior parental reproductive problems or bleeding during the current pregnancy. Therefore, it cannot be concluded that the gestational hormonal exposure was causally related to the psychoses present in these patients. In order to obtain more conclusive data, there will need to be continued monitoring of parental reproductive histories and gestational environmental exposures in autistic and schizophrenic children.

Autistic Disorder↗