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Biomedical subjects

A D Forrest

Publications and source records attributed to A D Forrest.

At least 19 recordsLinked to original sources
PubMed2004

Population genetic structure in European populations of Spiranthes romanzoffiana set in the context of other genetic studies on orchids.

Spiranthes romanzoffiana Cham. is restricted in Europe to the British Isles, where it is recognised as a conservation priority species due to frequent extirpation of populations along with no evidence of seed set; vegetative reproduction has been invoked as the sole means of perpetuation and dispersal. To investigate the reproductive ecology of this species, 17 populations have been sampled for chloroplast microsatellites and amplified fragment length polymorphisms (AFLPs). These markers revealed a previously unsuspected genetic-geographic split in the species, which correlates with differences in patterns of within-population variation. Northern populations were fixed for one chloroplast haplotype but showed high levels of AFLP genotypic diversity consistent with sexual reproduction (proportion of genotypes distinguishable, PD = 0.98). More southerly populations showed fixed differences from the northern populations in their chloroplast haplotype and for 10 AFLP markers. They harboured only 12 unique multilocus genotypes among 113 individuals from six populations (PD = 0.11). These genotypes differed mostly by single bands, and none by more than 4/138 loci, with identical multilocus genotypes occurring in widely separated populations. This uniformity in southern populations is consistent with agamospermous or autogamous reproduction, and/or an extreme population bottleneck. Finally, the observed patterns of population differentiation in S. romanzoffiana are compared with other studies of orchids, revealing a wide range of values that belie recent contrasting published generalisations that claim that orchids show either higher, or lower, levels of population differentiation than other plant families.

Chloroplasts↗
PubMed1976

Assessment of drugs in schizophrenia. Diagnosis and patient selection.

It would seem that some set of operational definitions are required for the spectrum of psychotic patients often embraced by the rubric schizophrenia. The problems of acute (first-admission) and chronic patients have been described. At the present time 'relapse re-admissions' would seem to constitute the best population for drug evaluations. The importance of factors such as age, sex, ethnics, geography and length of history has been emphasized. Finally the importance of carefully excluding patients who would be at risk from pre-existing disease or hypersensitivity has been emphasized.

Acute Disease↗
PubMed1976

Long-term follow-up of schizophrenic patients in Edinburgh.

This study is a 12-year follow-up of 153 subjects diagnosed as suffering from schizophrenia or paranoid psychoses. They had their key discharge in the years 1959-61 and were first followed-up at 12 months after discharge (Renton et al. ((1963)). Important findings were that outcome was related to mental state on discharge and also to the factor of continued neuroleptic medication. At this second follow-up 12 years later the important issues that have emerged are the differences in outcome between men and women and the apparently high death rate for men. The outcome in term of work, re-admission to hospital and death was much worse for male subjects.

Adult↗
PubMed1975

The assessment of thiothixene in chronic schizophrenia. A double-blind controlled trial.

The results are reported of a double-blind controlled trial of a recently introduced major tranquilizer thiothixene (Navane, Pfizer) against chlorpromazine in 24 chronic schizophrenics in the Royal Edinburgh Hospital, Edinburgh, Scotland. Additionally, a limited experiment in withdrawal of routine tranquilizers in these patients (one month) was carried out prior to the trial. Changes in manifest psychosis (symptoms) and social disability were assessed by the use of the Lorr scale (IMPS) and the Nurses' Observation Scale for Inpatient Evaluation (NOSIE) at suitable intervals. The results indicated that thiothixene conferred no advantage over chlorpromazine in symptom relief or social improvement. Serial measures showed no significant change in these patients as a group when on active drugs as opposed to placebo, or with the course of time. 12.5% of patients relapsed during the placebo period: these patients were younger than the non-relapsers and had received larger daily doses of phenothiazines prior to the trial.

Adult↗