Search PubMed⌕ Search

Biomedical subjects

M Byrne

Publications and source records attributed to M Byrne.

At least 19 recordsLinked to original sources
PubMed2002

Childhood behaviour, psychotic symptoms and psychosis onset in young people at high risk of schizophrenia: early findings from the edinburgh high risk study.

BACKGROUND: Several studies suggest that many patients with schizophrenia have pre-morbid neurodevelopmental abnormalities. This study examines how behavioural abnormalities are associated with mild psychotic symptoms and later schizophrenic illness. METHODS: Maternal ratings on the Child Behavior Checklist (CBCL) of the early behaviour of 155 subjects were obtained at entry to the Edinburgh study of people at high risk of schizophrenia. These maternal ratings were compared in those with and without psychotic symptoms and used to predict the later onset of psychosis. RESULTS: The CBCL syndrome scores for the children prior to age 13 did not distinguish any of the study groups at entry to the study. In the ratings made for the subjects when aged from 13 to 16, delinquent behaviour and 'other problems' were weakly associated with these symptoms. However, with the exception of somatic symptoms and thought problems, the age 13-16 scales were significant predictors of later schizophrenic illness. This was true also for some of the ratings prior to age 13. CONCLUSIONS: Various behaviours, in particular, withdrawn and delinquent-aggressive behaviour in adolescents at risk of schizophrenia may predict later onset of the illness. These behaviours, however, are far less predictive of isolated psychotic symptoms prior to psychosis onset.

Adolescent↗
PubMed2002

Sustained attention in young people at high risk for schizophrenia.

BACKGROUND: Sustained attention has been found to be impaired in individuals suffering from schizophrenia and their close relatives. This has led to the hypothesis that impaired sustained attention is an indicator of vulnerability to schizophrenia. METHODS: The Edinburgh High Risk Study used the Continuous Performance Test-Identical Pairs version (CPT-IP) to assess sustained attention in 127 high risk participants, 30 controls and 15 first-episode schizophrenic patients. A second assessment was completed by 59 high risk and 18 control participants 18 months to 2 years after the first. RESULTS: No differences in attentional capacity were found between the high risk and control groups and there was no association between genetic liability to schizophrenia and poor performance on the CPT-IP. Additionally, no association between occurrence of psychotic symptoms in the high risk group and impaired attentional capacity was found. CONCLUSIONS: The results suggest that deficits in sustained attention are not indicative of a genetic vulnerability to schizophrenia, and are not associated with the occurrence of psychotic symptoms.

Adult↗
PubMed2002

Massive pseudotumour resection with recombinant factor VIIa (NovoSeven) cover.

Surgical resection is the only definitive treatment for haemophilic pseudotumour. For patients with high- responding factor (F)VIII inhibitors, the lack of reliable by-passing agents in the past has meant that surgery has been avoided in favour of conservative measures. The development of recombinant factor VIIa (rFVIIa) has revolutionized the management of surgery in these patients. We document the first successful report of the surgical resection of a massive pseudotumour in a patient with high responding FVIII inhibitors using rFVIIa to achieve haemostasis. Serial post-operative measurements indicated that FVII coagulation activity (FVII:C) levels were more sensitive to rFVIIa dose changes than the prothrombin time.

Adult↗
PubMed2001

Effect of social class at birth on risk and presentation of schizophrenia: case-control study.

OBJECTIVES: To examine if low parental social class increases children's risk of subsequently developing schizophrenia or modifies the presentation. DESIGN: Case-control study with historical controls. SETTING: Geographically defined region in south Dublin. PARTICIPANTS: 352 patients with first presentation of schizophrenia matched with the next registered same sex birth from the same birth registration district. MAIN OUTCOME MEASURES: Social class at birth. Age at presentation to psychiatric services, admission to hospital, and diagnosis of schizophrenia. RESULTS: Risk of schizophrenia was not increased in people from lower social classes. There was a slight excess risk among people in highest social classes (odds ratio 0.59, 95% confidence interval 0.40 to 0.85). However, the mean age at presentation was 24.8 years for patients whose parents were in the highest social class compared with 33.1 years for those in the lowest social class at birth. CONCLUSIONS: Although social class of origin does not seem to be an important risk factor for schizophrenia, it partially determines the age at which patients receive treatment. The relation between low social class at birth and poor outcome may be at least partially mediated through treatment delay.

Adult↗
PubMed2001

Dermatoglyphic fluctuating asymmetry and atypical handedness in schizophrenia.

Atypical handedness and dermatoglyphic abnormalities are hypothesized to reflect a neurodevelopmental disturbance in schizophrenia. Developmental instability, indexed by dermatoglyphic fluctuating asymmetry (FA), reflects the degree to which an individual's ontogenetic program is maintained and provides a useful framework in which to consider atypical handedness in schizophrenia. Thirty patients diagnosed with schizophrenia were compared with 37 matched healthy controls on levels of dermatoglyphic FA, a demonstration task determining hand preference and a test of relative hand skill. Multivariate analyses established that patients demonstrated greater FA and more atypical hand skill compared with controls. In patients, but not in controls, there was a strong positive association between a measure of FA and a measure of atypical hand skill, suggesting that these markers of neurodevelopmental disturbance are related in schizophrenia. On a measure of hand preference, patients were more likely than controls to be classified as mixed handed than either right or left handed. Results from the present study support the conjecture of greater developmental instability in schizophrenia affecting neurodevelopmental processes, including those conferring manual dominance.

Adult↗
PubMed2001

Is reduced dermatoglyphic a-b ridge count a reliable marker of developmental impairment in schizophrenia?

BACKGROUND: Finger and hand prints are formed during the late first and second trimester of foetal development, after which they remain unchanged. Their expression may be influenced by both genetic and environmental factors. Some studies have suggested that a reduced total finger ridge count (TFRC) and, in particular, a reduce total a-b ridge count (TABRC), may be associated with schizophrenia. AIM: To study these two variables in a large, ethnically homogenous sample and to compare our findings with those of other recent studies. METHOD: Finger and hand prints of 150 people with DSM-III-R schizophrenia were compared with those of 92 healthy controls. RESULTS: Patients had a reduced mean TABRC (P = 0.03) compared with controls. There was a significant (P=0.02) linear trend for lower TABRC and increasing incidence of schizophrenia (ORlineartrend = 1.3; 95%CI1.1-1.7), implying a continuous increase in the risk for schizophrenia with reduction in TABRC. No significant difference between groups was observed for TFRC. CONCLUSION: These results provide further evidence that dermatoglyphic abnormalities exist in at least some patients with schizophrenia and that the a-b ridge count may be a marker of disruption, probably environmental, that occurs when the developing brain may also be particularly vulnerable to such insult. These findings support the concept that some cases of schizophrenia may be due to adverse intrauterine events.

Adult↗
PubMed2001

Critical incident technique as a qualitative research method.

Critical incident technique is a helpful methodology used to examine a number of issues pertinent to nursing science. It allows nurses to understand the dimensions of their role in clinical settings and their interactions with patients and other clinicians. It also helps nurses understand nursing practice in a variety of roles (e.g., clinical educator, nurse informatician, faculty member). Researchers using this methodology should review Flanagan's original assumptions and compare them to their proposed methodology to determine whether CIT is the best fit. Additionally, researchers should compare this method to phenomenology, grounded theory, or hermeneutics to determine whether these approaches are more congruent with the research question. Critical incident technique can provide insight into nursing issues when used with rigor and when appropriate rationale is provided for data collection, interpretation, and analysis.

Data Collection↗
PubMed2001

The concept of informed consent in qualitative research.

Informed consent is an essential part of all research endeavors that involve human participants. The human rights of research participants must be protected. It is incumbent upon the qualitative researcher to provide a dynamic informed consent when study outcomes change. The violation of privacy is more apt to occur with in-depth interviews, which has implications for researchers to protect human rights throughout data collection, analysis, and dissemination.

Ethics↗
PubMed2001

Grounded theory as a qualitative research methodology.

Grounded theory as a qualitative research approach provides nurses with strategies to build theories in areas previously unexplored or under explored. Although similar to other inductive processes, this methodology differs in that it emerges from the discipline of sociology. In addition, strategies for data analysis differ according to each methodologist. As with other qualitative methods, the researcher must link philosophy, methodology, and research method for rigorous and credible scholarship.

Humans↗
PubMed2001

Development of leaf shape.

Variation among vascular plants in the initiation and patterning of leaves results in a diverse array of leaf shape, including the strap-like leaf of many grasses and the broad lamina of most eudicots. Recent findings highlight the importance of interactions between the shoot apical meristem (SAM) and developing leaf primordia in axis specification and the establishment of leaf shape. Global regulators of epigenetic states have been implicated in these interactions and may play a role in distinguishing founder cells and stem cells within the SAM.

Genes, Plant↗
PubMed2001

A factor model of the functional psychoses and the relationship of factors to clinical variables and brain morphology.

BACKGROUND: Despite more than 100 years of study, there remains no definitive diagnostic validation of the functional psychoses. Factor analysis suggests the presence of three or more psychopathological syndromes in functional psychoses as a whole. The relationship between these factors and cerebral anatomy has been investigated in schizophrenia only. This study aimed to address the relationship of symptom factors to clinically important variables and cerebral anatomy in a sample of psychotic patients with a spread of diagnoses. METHODS: In a sample of patients with functional psychoses, symptom data was obtained on four consecutive admissions using the OPCRIT symptom checklist. OPCRIT data was used to generate operational diagnoses in accordance with pre-set criteria and a principle components analysis was performed on symptom data. Factor loadings were compared between each admission to examine factor stability over time. Factor scores at first admission were also correlated with clinical variables obtained from patients' case notes. From the sample of 204 patients, 64 subjects were recruited and underwent an MRI scan of the brain. Regional anatomical volumes were compared with diagnosis and factor loadings at first admission. RESULTS: A principal components analysis gave a four-factor solution of 'manic', 'depressive', 'disorganization' and 'reality distortion' factors at each admission. Factors showed a high degree of stability over the four admissions studied. The factors were significantly associated with several clinical variables. Three of the four factors were associated with a specific pattern of cerebral anatomy. CONCLUSIONS: This study suggests that factors may correspond to relatively specific disease processes underlying functional psychotic illness. We propose that the use of symptom factors may facilitate the investigation of the underlying mechanisms of psychotic illness.

Activities of Daily Living↗