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G Harrison

Publications and source records attributed to G Harrison.

At least 73 records · Page 4Linked to original sources
PubMed1997

The predictive validity of a diagnosis of schizophrenia. A report from the International Study of Schizophrenia (ISoS) coordinated by the World Health Organization and the Department of Psychiatry, University of Nottingham.

BACKGROUND: Outcome is important in the validation of psychiatric diagnosis, as most disorders lack clinicopathological correlates. We describe the predictive validity of four definitions of schizophrenia (DSM-III-R, ICD-10, ICD-9 and CATEGO S+), in a representative cohort of patients selected during their first episode of psychosis. METHOD: Each definition of schizophrenia was applied to 99 patients. Their respective ability to predict 13-year outcome (Global Assessment of Functioning scales) was assessed. RESULTS: DSM-III-R and ICD-10 diagnoses of schizophrenia have high predictive validity for long-term outcome, and both provide relatively stable diagnoses. ICD-9 is reasonably good at predicting disability, but not symptoms, and CATEGO S+ showed no predictive validity. Adding six-month duration criteria to ICD-10, ICD-9 and CATEGO S+ improved their predictive validity, and removing the six-month duration criterion from DSM-III-R commensurately reduced predictive validity. CONCLUSIONS: Modern diagnostic systems (DSM-III-R and ICD-10) have high predictive validity, and are superior to ICD-9. The six-month duration criterion of DSM-III-R schizophrenia accounts for its predictive validity and stability over 13 years, but restricts its use in first-episode studies. The one-month duration criterion of ICD-10 is less restrictive, without major compromises in predictive validity or stability.

Adolescent↗
PubMed1997

Incidence of schizophrenia in Nottingham. A comparison of two cohorts, 1978-80 and 1992-94.

BACKGROUND: Several studies have reported a decline of up to 50% in the incidence of schizophrenia over recent decades. We aimed to measure changes in the incidence and diagnostic patterns of first-episode psychosis by comparing two Nottingham cohorts, identified in two equal periods separated by 14 years. METHOD: Two prospectively ascertained cohorts of first-episode psychotic disorder were identified over the time periods 1978-80 and 1992-94. The earlier cohort was of the World Health Organization Determinants of Outcome of Severe Mental Disorder (DOSMD) ten-country study. The later cohort was obtained using similar methodology. Both groups were diagnosed using ICD-10 diagnostic criteria and age-standardised incidence rates were compared. RESULTS: The standardised incidence rate for all psychotic disorders rose slightly from 2.49 to 2.87 per 10000 population per year, but the F20 classification fell significantly by over a third (1.41 to 0.87 per 10000 per year). The second study group (1992-1994) included a greater diversity of psychotic diagnoses compared with the first, in particular an increased proportion of acute and drug-related psychoses. CONCLUSIONS: Methodological considerations call for caution in interpreting such data, but we conclude that the significant fall in the narrowly defined diagnostic category of schizophrenia reflects a real change in the syndromal presentation of psychotic disorders.

Adolescent↗
PubMed1997

The Ty1-copia group of retrotransposons in plants: genomic organisation, evolution, and use as molecular markers.

The genomic organisation and diversity of the Ty1-copia group retrotransposons has been investigated in several crop plants and their relatives from both dicotyledonous and monocotyledonous families, including potato (Solanum tuberosum), faba beans (Vicia faba), Vicia melanops, Vicia sativa, barley (Hordeum vulgare), rye (Secale cereale), and onion (Allium cepa). Extreme heterogeneity in the sequence of the Ty1-copia retrotransposons from all these plants was revealed following sequence analysis of reverse transcriptase fragments. The estimated copy numbers of the Ty1-copia group retrotransposons for the genomes of S. tuberosum, L. esculentum, A. cepa, S. cereale, and V. faba is highly variable, ranging from a few hundred to approximately a million copies per genome. In situ hybridisation data from metaphase and prophase chromosomes of V. faba, S. cereale, and H. vulgare suggest that retrotransposon sequences are dispersed throughout the euchromatic regions of the genome but are almost undetectable in most heterochromatic regions. In contrast, similar data from metaphase chromosomes of A. cepa suggests that although retrotransposon sequences are dispersed throughout the euchromatic regions of the genome, they are predominantly concentrated in the terminal heterochromatin. These results are discussed in the context of the role played by the Ty1-copia group retrotransposons in the evolution of the plant genome. Lastly, the application of retrotransposon sequences as genetic markers for mapping genomes and for studying genetic biodiversity in plants is presented.

Chromosome Mapping↗
PubMed1996

The Ty1-copia group retrotransposons in Vicia species: copy number, sequence heterogeneity and chromosomal localisation.

We present an in-depth study of the Ty1-copia group of retrotransposons within the plant genus Vicia, which contains species with widely differing genome sizes. We have compared the numbers and sequence heterogeneities of these genetic elements in three diploid Vicia species chosen to represent large (V. faba, 1C = 13.3 pg), medium (V. melanops, 1C = 11.5 pg) and small (V. sativa, 1C = 2.3 pg) genomes within the genus. The copy numbers of the retrotransposons are all high but vary greatly, with V. faba containing approximately 10(6) copies, V. melanops about 1000 copies and V. sativa 5000 copies. The degree of sequence heterogeneity of Ty1-copia group elements correlates with their copy number within each genome, but neither heterogeneity nor copy number are related to the genome size of the host. In situ hybridization to metaphase chromosomes shows that the retrotransposons in V.faba are distributed throughout all chromosomes but are much less abundant in certain heterochromatic regions. These results are discussed in the context of plant retrotransposon evolution.

Amino Acid Sequence↗
PubMed1996

Variability of post-void residual urine volume in the elderly.

Residual urine volume, though clinically important as a diagnostic tool, is reported to be variable and unreliable. Variability was examined among 14 geriatric patients, mean age 77 years. Residual urine was measured by ultrasound at three different times of day on each of two visits separated by 2-4 weeks. Results were examined by analysis of variance. Mean residual urine was 154 ml. Between-patient variability was large [standard deviation (SD) 246 ml]. There was no significant difference between values in men and women, nor between visits. Within-patient variability was large because of a large systematic variation with time of day (SD 128 ml), with greatest volumes in the early morning. The inherent, random variability of the measurement was much smaller than this (SD 44 ml). If the physiological factors causing the temporal variation could be controlled, more reproducible measurements would be possible.

Aged↗
PubMed1996

Long-term follow-up of schizophrenia in 16 countries. A description of the International Study of Schizophrenia conducted by the World Health Organization.

An unexpected finding of the International Pilot Study of Schizophrenia, launched by the World Health Organization (WHO) in 1967, was that patients in countries outside Europe and the United States have a more favourable short- and medium-term course of the disease than those seen in developed countries. Since then, WHO has intensified its schizophrenia research programme and has initiated a set of international studies that have confirmed these initial findings and explored possible reasons for such differences in the course and outcome of schizophrenia. While such work has provided important findings and has generated additional pertinent hypotheses, it did not explain the differences in outcome. The present paper describes a new initiative in which approximately 2500 subjects involved in previous WHO multicentre schizophrenia studies are being followed up for between 15 and 25 years after initial examination. Nineteen research centres in 16 countries are taking part in this work. The research methodology is described.

Adult↗
PubMed1996

The Ty1-copia group retrotransposons of Allium cepa are distributed throughout the chromosomes but are enriched in the terminal heterochromatin.

The genomic organization and diversity of the Ty1-copia group retrotransposons has been investigated in a monocotyledonous plant, Allium cepa. We used the polymerase chain reaction (PCR) to generate sequences corresponding to a conserved domain of the reverse transcriptase gene of Ty1-copia retrotransposons in this plant. Sequence analysis of 27 of these PCR products shows that they are a highly heterogeneous population, a feature which is common in plants but not in yeast and Drosophila. Slot-blot analysis shows there are 100,000-200,000 copies of Ty1-copia group retrotransposons within the A. cepa genome (2C = 31.7 pg), indicating that they are a significant component of the genome of this plant. In situ hybridization to metaphase chromosomes reveals that Ty1-copia retrotransposons are distributed throughout the euchromatin of all chromosomes of A. cepa but are enriched in the terminal heterochromatic regions, which contain tandem arrays of satellite sequences. This is the first clear evidence for the presence of Ty1-copia retrotransposons in the terminal heterochromatin of plants and contrasts with the distribution of these elements in other plant species.

Allium↗
PubMed1996

Predicting the long-term outcome of schizophrenia.

Predictors of long-term (13 year) outcome of schizophrenia are reported for a representative cohort of 'treated incidence' patients ascertained on their first contact with Nottingham psychiatric services between 1978-80. An initial (baseline) model including previously reported predictors of 2-year outcome (age, gender, ever married, acuteness of onset) and length of untreated illness was used to predict a range of outcome measures covering the domains of disability, psychopathology, hospitalization, employment, social activity, and global outcome. This model demonstrated significant prognostic ability across all non-hospitalization outcomes under both ICD-10 and ICD-9 diagnoses of schizophrenia, but was attenuated under broad (ICD-9 and CATEGO S, P or O) and restrictive (S+) diagnostic classifications. Female gender predicted more favourable outcome under all diagnostic classifications except S+. In an extended analysis, the addition of initial 2-year course type substantially increased the prognostic ability of the model under all diagnostic classifications and enabled over 30% of the variance in global ratings of disability and symptoms to be predicted. In this extended model female gender predicted more favourable outcome over and above the effect of course type, across most domains under ICD-10, and for disability and psychopathology under other diagnostic classifications. The inclusion of measures of psychopathology at the time of first assessment, pre-morbid functioning, and duration of index admission conferred only marginal additional predictive ability for respective outcomes in the domains of psychopathology, social activity, employment and hospitalization. Hospitalization during the past year was the most difficult outcome to predict under any model suggesting that resource utilization represents the 'administrative outcome' of schizophrenia and serves as a poor proxy for broader concerns in the era of community care. These data demonstrate that key demographic variables and the mode of onset influence the long-term course of schizophrenia, but that early course type is a particularly strong predictor.

Adult↗
PubMed1996

Pre-operative oral administration of morphine in day-case gynaecological laparoscopy.

The analgesic effect of morphine sulphate 10 mg by mouth given pre-operatively on pain after gynaecological laparoscopy was studied in a randomised, prospective, double-blind, placebo-controlled comparison. Two groups of 56 patients were studied one group undergoing diagnostic laparoscopy and the other laparoscopic sterilisation. All patients received a standard anaesthetic after premedication with morphine or placebo 1 h before the operation. Morphine premedication did not significantly influence postoperative pain as assessed on a visual analogue scale in either group and postoperative opioid consumption was unaffected. Premedication with morphine 10 mg orally does not significantly decrease pain after day-case gynaecological laparoscopy.

Administration, Oral↗
PubMed1996

The course of schizophrenia over 13 years. A report from the International Study on Schizophrenia (ISoS) coordinated by the World Health Organization.

BACKGROUND: This paper describes the 13 year course of illness in an epidemiologically defined and representative cohort of patients selected when they were experiencing their first episode of schizophrenia. METHOD: In a 13-year follow-up study of 67 patients with ICD-9 schizophrenia, identified in Nottingham in 1978-80, the course of illness (symptoms, disability and hospitalisation) was assessed using standardised instruments, applied at onset, 1,2, and 13 years. Time to first relapse and first readmission were calculated and plotted as survival curves and patients were assigned to the course types described by Ciompi. RESULTS: The survival curves show that first relapses and first readmissions occur during the first five years. The amount of time spent in psychotic episodes and in hospital is greatest in the first year of follow-up, but stable thereafter. Social adjustment improves from entry to the study to the first follow-up year, but there is a small deterioration in social adjustment between 2 and 13 years. CONCLUSIONS: The findings reported suggest that after the initial episode the course of schizophrenia is relatively stable. The data support neither concepts of progressive deterioration nor progressive amelioration. There was no evidence of a "late recovery'.

Adolescent↗
PubMed1995

The phosphatidylinositol-glycolipid anchor on alkaline phosphatase facilitates mineralization initiation in vitro.

Alkaline phosphatase (AP) is required for the proper mineralization of cartilage and bone. The enzyme is localized to the outer surface of cells through a phosphatidylinositol-glycolipid anchor, which is covalently attached to the carboxyl terminus of the protein. In calcifying cartilage, AP-rich matrix vesicles (MVs) are released into the matrix from chondrocytes, and apatite formation is initiated within and around these particles. In this paper we examine the role of the AP glycolipid anchor using an in vitro mineralization assay system. AP was purified to homogeneity, and the purified enzyme was used to drive mineral formation in vitro with and without the anchor. Mineral formation was initiated through phosphate release from beta-glycerol phosphate (beta-GP). The amount of PO4(-3) released was similar whether the anchor was present or absent. However, SEM and X-ray microanalysis revealed that the mineral produced by anchored AP was indistinguishable from that produced by MVs and that both of those minerals were more apatite-like than mineral formed by soluble AP or through spontaneous precipitation. Taken together, the data suggest that in addition to providing PO4(-3) to drive mineralization, AP influences the nature of the mineral formed. Further, AP containing its glycolipid anchor produces mineral comparable with that formed by tissue-derived MVs. Thus, in the absence of extracellular matrix, MV mineralization in vitro can be emulated by glycolipid-anchor containing AP.

Alkaline Phosphatase↗
PubMed1995

Characteristics of outcome in schizophrenia at 13 years.

BACKGROUND: This paper describes the 13-year outcome of an epidemiologically defined and representative cohort of patients selected when they were experiencing their first episode of schizophrenia. METHOD: In a 13-year follow-up study of a cohort identified in Nottingham in 1978-80, the outcome (symptoms, disability, residence and treatment) was assessed using standardised instruments. RESULTS: Four of the original 67 patients with ICD-9 schizophrenia were lost to follow-up and five were dead: 52% were without psychotic symptoms in the last two years of follow-up, 52% were without negative symptoms and 55% showed good/fair social functioning. However, only 17% were alive at follow-up, without symptoms and disability, and receiving no treatment. CONCLUSIONS: The findings reported are similar to those of other long-term follow-up studies of schizophrenia and also to 5-year follow-up studies. Kraepelin's emphasis on the longitudinal implications of a diagnosis of schizophrenia are supported, but may be over-pessimistic.

Adolescent↗
PubMed1995

Psychological consequences of the Kegworth air disaster.

BACKGROUND: The study sought to quantify psychiatric morbidity among survivors of a major air crash and to identify aetiological factors linked with post-traumatic stress disorder (PTSD). METHOD: Sixty-eight of the 79 survivors (86%) were assessed at a clinical interview within one year of the disaster. The majority also completed the General Health Questionnaire, the Impact of Events Scale (IES) and the Zung Anxiety and Depression Scales. RESULTS: Fifty-four of the study group (79%) met DSM-III-R criteria for a psychiatric disorder within one year of the disaster, of whom 27 (50%) had PTSD. Those who saw injured or dead people at the scene, or had sustained less severe injuries as measured by their Injury Severity Scores, or were under 35 years old, were significantly more likely to develop PTSD. CONCLUSIONS: High rates of psychiatric morbidity are found in survivors of transportation disasters. Further studies are needed to identify those at most risk and to evaluate the benefits of psychological intervention.

Adult↗