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D Campion

Publications and source records attributed to D Campion.

85 records · Page 5Linked to original sources
PubMed1992

Evidence for a pseudoautosomal locus for schizophrenia. I: A replication study using phenotype analysis.

A locus for schizophrenia within the pseudoautosomal region of chromosomes X and Y has been suggested by Crow on the basis of epidemiological data. The present report replicates this finding in a sample of 38 French multiply affected families with schizophrenia. Sibship and pairwise analysis, with or without weighted-pair correction, with three different systems of family classifications, showed there to be an excess of same-sex pairs in paternally derived sibships, as predicted by the pseudoautosomal hypothesis.

Female↗
PubMed1992

Evidence for a pseudoautosomal locus for schizophrenia. II: Replication of a non-random segregation of alleles at the DXYS14 locus.

Because of an association between sexual aneuploidies and schizophrenia, and because schizophrenic siblings have been found to be more often of the same than of the opposite sex, the susceptibility locus for schizophrenia is thought to lie within the pseudoautosomal region of the sex chromosomes. We analysed 33 sibships comprising 18 pairs, 13 trios, and 2 quartets of affected siblings, and found support for non-random segregation of of alleles at the DXYS14 locus in affected siblings. These findings are consistent with the pseudoautosomal hypothesis for schizophrenia and favour a genetic linkage between DXYS14 and the disease.

Alleles↗
PubMed1990

Subtyping familial schizophrenia: reliability, concordance, and stability.

This report examines the reliability, concordance, and long-term stability of the subtypes of schizophrenia defined by four major diagnostic systems (DSM-III, DSM-III-R, ICD-10, and Tsuang-Winokur criteria) and rated both for the first hospitalization and for a best estimate diagnosis reflecting lifetime evolution of symptomatology. Schizophrenics studied belonged to two samples of multiply affected families, namely a sample selected in France and a sample of non-metropolitan French identified in the island of La Réunion. ICD-10 and DSM-III-R show opposite stringency regarding subtyping of schizophrenia, with DSM-III-R having a narrow and ICD-10 a broader definition of specific subtypes. Long-term stability of each subtype was fairly good, stability being the highest for hebephrenics and only intermediate for paranoid and undifferentiated subtypes. Comparison of two different cultural and geographical regions reveals an overall similarity of subtype frequencies in familial schizophrenia. The implications of the results for the choice of diagnostic procedures in family studies of schizophrenia are discussed.

Adolescent↗
PubMed1983

Heterotic and maternal effects on body composition of LL and SS rats and their reciprocals at two ages.

A diallel cross between two genetically similar growth strain lines of rats, varying greatly in body size was made in order to evaluate the differences in carcass composition at 15 and 25 weeks of age. Traits assessed were percentages of dry matter, ash, fat, and protein of empty body weight. Analysis of variance of the components in the model indicated no significant differences in carcass constituents at age 15 weeks except dry matter. Rat carcasses at 25 weeks of age showed an increase in fat per cent (p less than .05) from 15 to 25 weeks of age. A significant maternal influence was expressed for fat per cent in favor of the LL dam and for protein per cent favoring the SS female. Heterosis was more evident (p less than .05) at 25 weeks than 15 weeks for ash, fat, and protein percentages.

Age Factors↗
PubMedDate not supplied

Halofenate. Its selection and trial as a primary uricosuric agent.

In vitro binding studies on antiinflammatory and uricosuric acidic anions performed under "physiologic" conditions have demonstrated that these substances displace urate from its protein bond. The property of urate displacement appears to be a useful marker for potential uricosuric activity in vivo, and thereby a means to detect novel uricosuric drugs. One such drug, halofenate, was indeed a safe and effective uricosuric (comparable to probenecid) when used to treat hyperuricemia/gout over the long term; it did result in a modest and variable fall in serum lipid concentrations. However, used as a single fixed dose, halofenate did not produce a marked and consistent effect on the elevated serum triglyceride concentrations so commonly present in gouty patients.

Adult↗
PubMedDate not supplied

No evidence for involvement of KCNN3 (hSKCa3) potassium channel gene in familial and isolated cases of schizophrenia.

Several studies have reported in schizophrenia a decrease of age of onset in successive family generations, and this observation is consistent with anticipation. Anticipation is known to result from expansion of CAG repeats in several neurodegenerative disorders. Longer alleles of the KCNN3 gene, which contains a highly polymorphic CAG repeat, and encodes a neuronal small conductance calcium-activated potassium channel, have recently been shown to be over-represented in sporadic cases of schizophrenia. In this report, we tested the hypothesis of an association between longer alleles of CAG repeat in the KCNN3 gene and schizophrenia in 20 families with clinical evidence for anticipation and in 151 unrelated schizophrenic cases. No significant difference in the distributions of allele frequencies was observed between familial cases of schizophrenia and controls, and between unrelated cases and controls. Furthermore, no intergenerational CAG repeat instability was detected in the 20 families. Our results do not support the involvement of the KCNN3 (hSKCa3) gene in the etiology of schizophrenia.

Adult↗
PubMedDate not supplied

[Dynamic DNA mutations, anticipation and schizophrenia].

Recently, a new form of human mutation-expansion of trinucleotide repeats-has been found to cause fragile X syndrome, Huntington's disease and other neurodegenerative diseases. These diseases are characterized by unusual patterns of inheritance, in particular, genetic anticipation in which the severity of the disorder increases and the age at onset decreases in successive generations of a pedigree. This phenomenon, formerly ascribed to observation biases, correlates with the expansion of trinucleotide repeat sequences. Two recent studies indicate that anticipation is present in familial schizophrenia. These findings support both an active search for unstable trinucleotide repeat sequences in schizophrenia and reconsideration of the genetic models used in this disorder.

Adolescent↗
PubMedDate not supplied

[Memory disorders in the elderly: complementary examinations--for whom?].

Recognizing the existence of memory disorders in elderly subjects necessarily involves developing a diagnostic strategy to identify the causes. Three types of complementary investigation are available: neurophysiological and neurobiological tests, and anatomical and functional brain imaging studies. Major efforts have been made to identify diagnostic markers on the electroencephalogram. Quantified EEG may have a certain value. However, it provides a plethora of data and there is no consensus on which items are most relevant on the EEG, whether the patient is awake or asleep. Evoked 'cognitive' potentials may also provide useful data, particularly to distinguish between the different types of degenerative dementia. Exaggerated pupil dilation in response to a mydriatric drug has also been put forward as a diagnostic test. The results, however, are controversial. For the time being there is no diagnostic laboratory parameter that can be used routinely, even if studies of the proteins tau and P97 are promising. Molecular genetics-based studies have identified a number of chromosomal abnormalities in certain families. Apart from studies of chromosome 19 and apolipoprotein 3, these markers have no practical utility. Allele sigma 4 is associated with a higher risk of Alzheimer's disease. Apolipoprotein E phenotyping can of course be of diagnostic value, but no more so than neuropsychological or neuroimaging methods. On the other hand, it is difficult to derive a predictive test. It also seems difficult to develop a diagnostic strategy without including brain imaging studies. The value of morphological imaging (CT, MRI) in the diagnosis of dementias is clear. Volumetric measurements of certain brain structures might be a useful diagnostic approach for early detection. Functional brain imaging methods (PET and SPECT) appear particularly suited to the diagnosis of degenerative dementias. The presence of functional abnormalities at onset, and, even before the first clinical signs appear, is clearly valuable.

Aged↗