Search PubMed⌕ Search

Biomedical subjects

R A Dickson

Publications and source records attributed to R A Dickson.

At least 37 records · Page 2Linked to original sources
PubMed1998

Stimulation of inflammatory markers after blunt trauma.

BACKGROUND: Inflammatory mediators are released after trauma and may be related to the pathogenesis of sepsis. A prospective combined study of the pattern of release of an inflammatory mediator, interleukin (IL) 6, leucocyte activation (polymorphonuclear leucocyte (PMN) CD11b receptor expression and plasma elastase-alpha1 proteinase inhibitor complex (E-alpha1PI)) and soluble endothelial adhesion molecule expression (soluble E-selectin (sE-selectin) and soluble intracellular adhesion molecule 1 (sICAM-1)) was performed in patients suffering blunt trauma without adult respiratory distress syndrome (ARDS) or multiple organ failure syndrome (MOFS). METHODS: Thirty-one patients with a mean Injury Severity Score (ISS) of 14 (range 9-57) were studied. Venous blood samples were collected within 6 h of injury and then at 1, 3, 5 and 7 days. Leucocyte CD11b expression was quantified by flow cytometry. Serum IL-6, plasma E-alpha1PI, sE-selectin and sICAM-1 were measured by enzyme-linked immunosorbent assay. RESULTS: Serum IL-6, CD11b expression and E-alpha1PI levels were significantly raised above control values (P < 0.0001) on admission, slowly returning towards control values over the study period (median IL-6, 140 pg/ml versus undetectable; CD11b, 14.8 versus 6.4 mean channel fluorescence units; E-alpha1 PI, 208 versus 52 microg/l). The sICAM-1 level rose to a median of 539 ng/ml at 5 days (control 243 ng/ml). The median sE-selectin level also progressively increased to a maximum level of 80 ng/ml at 5 days (control 49 ng/ml). Eleven patients developed postoperative sepsis. Significant differences in CD11b expression were seen at days 3, 5 and 7 and in E-alpha1 PI at 6 h, 24 h and 3 days in patients who subsequently developed sepsis (P < 0.05). Severe injury (ISS 16 or greater) was associated with significantly greater responses in these measurements. CONCLUSION: These data show that markers of inflammation are specifically stimulated by trauma even when ARDS and MOFS do not occur. The CD11b receptor on PMNs may be useful in screening patients destined to develop post-traumatic sepsis.

Adult↗
PubMed1998

Pregnancy of a patient treated with clozapine.

The authors describe the case of a patient with treatment-resistant schizophrenia who became pregnant after switching from conventional neuroleptic medications to clozapine, an atypical antipsychotic medication that does not cause hyperprolactinemia. Gestational diabetes, possibly exacerbated by clozapine, complicated management of her pregnancy. Comprehensive community support and psychiatric rehabilitation, combined with a positive response to clozapine, contributed to satisfying the patient's goal of having a healthy baby and being able to take the baby home to live with her and her husband.

Adult↗
PubMed1998

Hospital days in clozapine-treated patients.

OBJECTIVE: To examine inpatient hospital days used by a group of patients with treatment-resistant schizophrenia for 3 years before and 3 years after clozapine initiation. METHOD: A retrospective chart review of 26 consecutive admissions to an outpatient clozapine clinic was conducted for a 6-year period. The total number of hospital days was recorded. RESULTS: Patients separated into 3 groups: those who used clozapine for 3 uninterrupted years (N = 11, 42.3%), those who interrupted but resumed clozapine and continued on to 3 years (N = 4, 15.4%), and those who abandoned clozapine treatment (N = 11, 42.3%). Only the group that was continuously on clozapine showed a decline in percentage of inpatient days during the 3-year follow-up period. Three of the 11 patients who discontinued clozapine died during the posttreatment period: 2 suicides and 1 "death by misadventure." CONCLUSIONS: Continuous clozapine treatment significantly reduces days in hospital; this reduction was sustained throughout 3 years' follow-up. While the sample size is small, all patients were tracked over a 6-year period, and both drug continuers and dropouts were followed. The reduction in inpatient days may be lost if patients stop and then restart clozapine. For patients who do not respond to or abandon trials of clozapine, there is an urgent need to develop more effective treatment strategies.

Adult↗
PubMed1998

Clozapine reduces violence and persistent aggression in schizophrenia.

Violence and persistent aggression are serious problems in the general population and among certain psychiatric patients. Violence and persistent aggression have been associated with suicidal ideation and substance abuse, characteristics of chronically ill, and in many instances, treatment-resistant schizophrenia individuals. Assessment of dangerousness in psychiatric patients involves evaluation of sociodemographic and clinical factors. A substantial number of neurologic and psychiatric disorders are associated with pathologic anger and aggression; of these, the association between schizophrenia and violence/aggression is the best described. Neurotransmitters that have been implicated in aggressive and violent behavior include serotonin, norepinephrine, and dopamine. Current pharmacotherapy of pathologic aggression involves the use of multiple agents on a trial-and-error basis, with varying degrees of response. Unfortunately, this approach subjects patients to numerous side effects, including the extrapyramidal symptoms associated with the use of conventional antipsychotics. This paper will review evidence for the efficacy of clozapine in the treatment of aggression and violence in the treatment-refractory patient. The reduction in violence and persistent aggression with clozapine treatment should improve the chances for integration of the schizophrenia patient into the community and provide cost savings to society.

Aggression↗
PubMed1996

Idiopathic scoliosis: biomechanics and biology.

For whatever reason, right-left asymmetry has attracted an illogical proportion of research effort. Non-structural scoliosis, for example secondary to a leg length inequality, is indeed a problem of right-left asymmetry, but structural scoliosis is a complex three-dimensional deformity involving all planes. Biomechanical, biological and clinical evidence indicates clearly that the problem is one of front-back asymmetry and not right-left. The importance of biological factors lies in their ability to bring the spinal column to and beyond its buckling threshold. Thus a taller and more slender spine is more liable to bend and, being stiffer in the sagittal plane, favours movement into other planes. This epitomises the spine of the scoliosis patient who is growing faster with a spinal template similar to other family members allowing idiopathic scoliosis to express itself genetically. It is the opposite condition to idiopathic hyperkyphosis (Scheuermann's disease), but this deformity is rotationally stable, thus remaining in the sagittal plane. The presence of an adjacent area of lordo-scoliosis below the region of hyperkyphosis testifies to the common nature of the pathogenesis of idiopathic scoliosis and Scheuermann's disease. It is the area of compensatory hyperlordosis below the Scheuermann's area that has obligatorily buckled and represents a human model supporting the lordosis theory, as does surgically tethering the back of the young growing human spine, which crankshafts accelerated progression. Similarly the only successful animal model of the formation of idopathic follows creation of a lordotic spinal segment in an otherwise kyphotic spine. For centuries, engineers have recognised that the mechanical behaviour of a column under load is influenced by geometry, as well as by material properties; it is clear that the spinal column also obeys these well-described laws.

Animals↗
PubMed1996

Tardive dyskinesia and positive and negative symptoms of schizophrenia. A study using instrumental measures.

BACKGROUND: Controversy surrounds the relationship between tardive dyskinesia (TD) and symptoms of schizophrenia. While some studies reported that negative symptoms of schizophrenia may be a risk factor for TD, others reported a relationship between TD and positive symptoms. METHOD: Eighty-four patients were studied, of whom 47 met criteria for TD. Clinical and instrumental procedures were used to increase the sensitivity of our assessments of the presence and severity of TD. Stepwise logistic and linear regression procedures were used to identify demographic variables, psychopathology, and motor parameters associated with the presence and severity of TD. RESULTS: A 3-factor model consisting of age, clinical tremor, and negative symptoms explained 25% of the variance in clinical TD severity. A 6-factor model consisting of female gender, instrumental and clinical measures of parkinsonism, positive, and negative symptoms explained 49% of the variance in severity of instrumentally derived dyskinesia. CONCLUSIONS: These results suggest that the presence of TD may be associated with positive symptoms; that the severity of TD may be related to negative symptoms; and that the relationship between negative symptoms and TD severity may be influenced by the presence of parkinsonism.

Adult↗
PubMed1996

Late-onset idiopathic scoliosis in children six to fourteen years old. A cross-sectional prevalence study.

We performed a point-prevalence survey of 15,799 children, six to fourteen years old, who formed part of a prospective longitudinal study. Our purpose was to detect the prevalence of scoliosis and to investigate associated factors. On the basis of the initial screening, 934 children (5.9 per cent) were referred for additional clinical and radiographic examinations; 896 children returned for this second evaluation. A lateral spinal curve with a Cobb angle of more than 5 degrees was seen in 431 children (2.7 per cent of the 15,799 children). Only seventy-six children (0.5 per cent) had a curve that met our definition of idiopathic scoliosis (a curve of more than 10 degrees with concordant apical rotation). The point-prevalence rate was higher in girls, and it increased with age. The rate was 0.1 per cent (four of 5246) in the age-group of six to eight years, 0.3 per cent (sixteen of 5831) in the age-group of nine to eleven years, and 1.2 per cent (fifty-six of 4722) in the age-group of twelve to fourteen years old. With allowance for the fact that different definitions of idiopathic scoliosis have been used in earlier studies, our results suggest that the natural history of idiopathic scoliosis may be becoming more benign spontaneously.

Adolescent↗
PubMed1995

The clozapine experience from a family perspective.

OBJECTIVE: To examine how the lives of family members of clozapine-treated patients with schizophrenia have been affected by this treatment. METHODS: Through the use of a questionnaire and an interview of family members, this qualitative study focused on the families' perceptions of change in their family member and the impact on the family unit. RESULTS: Fourteen patients and their family members participated. The family interview was conducted an average of 1.78 years after clozapine initiation (range 0.58 years to 3.73 years). Global ratings of behavioural change were positively and significantly correlated between all raters: patients, family members, and clinicians. Family members were positive about clozapine's effect on their relatives and the impact on the family. CONCLUSION: A positive response to clozapine decreases the burden on the family. This is in part the result of a decreased need for rehospitalization.

Adult↗
PubMed1995

Economics of schizophrenia.

OBJECTIVE: To discuss the costs associated with mental illnesses that constitute a significant percentage of the total direct health care costs, currently estimated at $1605 per person per year (9% of the gross national product). The cost of all mental illness in the US has been estimated at US$103.7 billion (1985 dollars), of which schizophrenia alone accounts for US$22.7 billion. METHOD: A number of studies that have attempted to evaluate the cost of therapies in schizophrenia are examined. RESULTS: While schizophrenia affects only 1% of the population, it accounts for 2.5% of total health care expenditures in the US. For first-admission patients suffering from schizophrenia, it would appear to cost less to provide the most clinically-effective treatments than to provide a good level of milieu care with special treatment. CONCLUSION: Community-based care can be less costly than conventional hospital-based programs and can improve patient quality of life. Inhospital programs that reduce length of stay with the use of medication clinics or day hospital care may achieve significant cost savings. A special challenge is the subgroup of patients suffering from schizophrenia that is neuroleptic-resistant. New drugs, such as the atypical neuroleptics, clozapine and risperidone, may prove to be highly cost-effective in treating schizophrenia by preventing relapse and reducing hospital lengths of stay.

Antipsychotic Agents↗
PubMed1995

Neurological injury in thoracolumbar burst fractures.

Many authors recommend surgery to remove retropulsed bone fragments from the canal in burst fractures to 'decompress' the spinal canal. We believe, however, that neurological damage occurs at the moment of injury when the anatomy is most distorted, and is not due to impingement in the resting positions observed afterwards. We studied 20 consecutive patients admitted to our spinal injuries unit over a two-year period with a T12 or L1 burst fracture. There was no correlation between bony or canal disruption and the degree of neurological compromise sustained but there was a significant correlation between the energy of the injury (as gauged by the Injury Severity Score) and the neurological status (p < 0.001). This suggests that neurological injury occurs at the time of trauma rather than being a result of pressure from fragments in the canal afterwards and questions the need to operate simply to remove these fragments.

Adolescent↗