Complexity preference in substance abusers and controls: relationships to diagnosis and personality variables

To assess the relationship between complexity preference as measured by the Barron-Welsh Revised Art Scale and models of arousal and personality, 36 male substance abusers and 24 community controls were given this tool as well as a battery of personality tests. Some support was found for the notion that emotionality, as measured by the Test of Emotional Styles, was associated with preference for complexity. Relevant neurobiological models of affective expression and hemispheric asymmetry are discussed in light of these findings.

Psychological deficit from excessive alcohol consumption: evidence from a co-twin control study

Twenty-five pairs of monozygotic twins discordant for either the alcohol dependence syndrome or heavy drinking were studied to determine the adverse cognitive effects of alcohol. The twins and their co-twins were well-matched for premorbid history and personality but twins with high alcohol consumption performed significantly less well overall on cognitive testing than their co-twins. Impaired performance in parts of the following tests was found: visual spatial ability, visual spatial recognition, Mill Hill vocabulary, Bexley Maudsley category sorting, tactual performance. The number of years of problem drinking correlated with inferior scores on subtests of the tactual performance test. This study provides further evidence that alcohol abuse produces long-term cognitive sequelae which may not be grossly evident in clinical practice, and which may occur even at relatively low levels of intake.

Genetic counselling for myotonic dystrophy: a comparison of lens examination and DNA linkage studies

Genetic counselling in presymptomatic individuals with a family history of myotonic dystrophy (DM) is problematic. A genetic test to identify the presymptomatic carrier of the gene for DM would therefore be advantageous. We report studies comparing ophthalmic examination with a genetic test based on DNA linkage studies in nine DM families. The genetic test involved the use of five probes from four loci linked to the DM locus. Some discrepancies between ophthalmic and genetic tests were observed. Genetic counselling following prediction of genetic status was possible for 18 out of 20 patients from seven out of nine families.

Recovery from general anesthesia

The pattern of recovery from anesthesia is ordinarily quite predictable. Using a limited number of drugs to provide anesthesia further improves predictability; it is more difficult to assign a cause for delayed emergence when multiple agents have been administered. We believe the recovery period is often more difficult to manage safely than induction and maintenance of anesthesia. During this phase, the effects of surgical trauma are superimposed on the patient's preexisting disease state, the anesthetic level is changing rapidly, respiratory function has not returned to normal, and circulatory reflexes may not have been regained. Because the patient is being moved from the operating room and care of the patient is being transferred from one person or team to others, vigilance and treatment may also be impaired. It is a period of care that warrants further study.

Endodontic considerations when fabricating overdentures

Successful use of an overdentures prosthesis depends on the successful completion and maintenance of endodontically-treated teeth. The process of completion and maintenance of teeth so treated in elderly individuals is difficult and less predictable. The purpose of this paper is to discuss treatment considerations to enhance success when treating elderly candidates for endodontic overdenture abutment retention.

Synergistic effects of azathioprine and ultraviolet light detected by sister chromatid exchange analysis

The immunosuppressant azathioprine and longwave ultraviolet (UV) light have been postulated to have a synergistic effect on DNA resulting in carcinogenic change. This study investigated the in vitro effect of UV light on renal transplant recipients (RTRs) immunosuppressed with azathioprine and prednisolone to prevent rejection and patients on azathioprine for skin conditions and normal controls on no drug therapy. The results show clearly that there is an increase in sister chromatid exchanges (SCEs) in both patient groups in response to UV light with the greatest increase shown by the RTRs. Both patient groups without exposure to UV also showed a significant increase, as compared with normal controls, with the RTRs again showing the highest level. Both patient groups also showed disruption of the cell cycle in response to UV light as measured by the proliferative rate index (PRI) but the controls did not. These findings support the hypothesis of a synergistic effect between azathioprine and UV light and correlate well with the clinical pattern of carcinogenesis observed in these patients, with RTRs having a well-documented increased risk of neoplasia, particularly skin carcinomas in light-exposed areas.

Unsound methodology in investigating a pseudoautosomal locus in schizophrenia

We have reservations about accepting the conclusions made by Crow et al (1989), namely that there is evidence that susceptibility to schizophrenia may be transmitted by a pseudoautosomal locus. In our view the methodology of the study is unsound. Additionally the data presented by the authors, when analysed correctly, do not support their hypothesis.

Carrier detection and prenatal diagnosis in Norrie disease

We report the use of DNA probes to determine carrier status in three young women from a large kindred with Norrie disease. One of the women requested prenatal diagnosis during pregnancy. In this pedigree, Norrie disease was not characterized by a deletion at DXS7.

Molecular analysis of recombination events in Drosophila

The locations of crossover junctions and gene conversion tracts, isolated in the rosy gene of Drosophila melanogaster, were determined using DNA sequencing and denaturing gradient gel electrophoresis. Frequent DNA sequence polymorphisms between the parental genes served as unselected genetic markers. All conversion tracts were continuous, and half of the reciprocal crossover events had conversion tracts at the crossover junction. These experiments have also identified the sequence polymorphisms responsible for altered gene expression in two naturally occurring rosy variants.

Recent and future molecular genetic research into schizophrenia

The difficulties anticipated in the application of molecular genetics to schizophrenia research have not prevented the first successful localization of a susceptibility gene for a subtype of schizophrenia. It is argued that this approach is the most useful of the possible molecular genetic strategies because it leads both to enhanced clinical genetic investigation and to further recombinant DNA research to clone and sequence schizophrenia susceptibility mutations. Future recombinant DNA research can now use long-range mapping and cloning techniques such as the chromosome walking/jumping approach and the strategy of cloning brain-specific cDNAs from brain mRNA. The identification of carriers for high-risk studies and the genetic validation of diagnosis appear to be the most promising clinical developments. Prenatal counseling will only become widely feasible when much more is known about the extent of heterogeneity of linkage in schizophrenia.

Understanding Romanowsky staining. 2. The staining mechanism of suspension-fixed cells, including influences of specimen morphology on the Romanowsky-Giemsa effect

Romanowsky staining of suspension-fixed lymphocytes and fibroblasts, deposited as monolayers on slides, involves an initial basic dyeing process followed by formation of a hydrophobic Azur B/Eosin Y complex at the more permeable and so faster staining cellular sites. This mechanism is shared with blood and marrow smears. However certain morphological features peculiar to suspension-fixed, cell culture-derived preparations also influence the staining pattern via rate control: namely the irregular and bulky profiles of fibroblasts, compared to the smoother and thinner lymphocytes; and the occasional superficial occlusion of cells by culture medium.

A duplication/deficient X chromosome in a girl with mental retardation and dysmorphic features

A structurally abnormal X chromosome was found in a nine year old girl with mild mental retardation and dysmorphic features. Subsequent clinical examination at 18 years of age showed tall stature and gonadal dysgenesis. Re-examination of her karyotype using a variety of banding techniques on prometaphase chromosomes allowed the identification of the abnormal chromosome as a duplication/deficient X chromosome, 46,Xder X(pter----q28::p11.2----pter). The clinical features are discussed in terms of karyotype/phenotype correlation.

An evaluation of reinforcement of genetic counselling on the consultand

This project studied the effect of reinforcement of genetic counselling in the home, on consultand recall of information discussed in the clinic. Acceptable recall was observed in 84% of 227 patients scored for recall of rate of recurrence, understanding of the nature of the disease at special risk and of its mechanism of origin. Our results show no significant difference in the frequency of acceptable recall after reinforcement of genetic counselling compared with an absence of reinforcement. The consultands' understanding was substantially affected by the type of genetic mechanism involved.