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A Cameron

Publications and source records attributed to A Cameron.

At least 73 records · Page 4Linked to original sources
PubMed1993

Impact of genetic counselling after neonatal screening for Duchenne muscular dystrophy.

In a pilot neonatal screening programme for Duchenne muscular dystrophy (DMD) conducted in the Canadian province of Manitoba, a cohort of eight affected males was identified between 1 January 1986 and 31 December 1989. Demographic information, knowledge of DMD, reproductive outcome, and attitudes to prenatal diagnosis and neonatal screening for DMD were obtained through questionnaires distributed in May 1992 to the eight sets of parents of index cases, two high probability carrier aunts, and one high probability carrier sister. Personal interviews were subsequently conducted in the summer of 1992. Although there is overall consensus among the families in favour of routine neonatal screening for DMD, five of seven subsequent pregnancies reported in six women were not monitored by prenatal diagnosis and have resulted in the birth of two affected boys. In a comparable time interval, prenatal diagnosis was acceptable to carrier females whose affected male relatives were traditionally diagnosed at four or five years. We conclude that, although molecular genetic analysis now allows for precise diagnosis of DMD, highly accurate carrier testing and prenatal diagnosis, very early DMD carrier identification, and genetic counselling after the identification of DMD males in a population based neonatal screening programme may not be an effective way of decreasing the number of repeat cases of DMD within families or the overall population frequency of DMD.

Adolescent↗
PubMed1992

Limitations of the triolein breath test.

Patients being investigated for intestinal absorptive capacity were classified as normals or malabsorbers on the basis of three fat absorption tests. Malabsorbers were further classified as mild, moderate, severe or gross according to severity of malabsorption. Using this classification system the triolein breath test was evaluated in 53 patients. Seventeen patients were excluded because their graph of percentage breath [14C]carbon dioxide versus time was exponential indicating that the peak [14C]-carbon dioxide may be occurring later than the six hour duration of the test. The sensitivity and specificity of the triolein breath test were found to be 100% and 96%, respectively and moderate correlations with the individual fat absorption tests were found. However, the breath test was limited in its capacity to predict the severity of malabsorption. Carbon dioxide output was also measured in order to determine the applicability of using an assumed value. The respiratory quotient and variability of results were high in nineteen patients indicating possible hyperventilation. In 32 patients with reproducible results and normal respiratory quotients the average carbon dioxide output was 8.66 mmol/kg per hour with a wide range of 5-12.4 mmol/kg per hour. Consequently the use of an assumed carbon dioxide output can introduce considerable errors in the triolein breath test. This study highlights drawbacks of the triolein breath test, particularly problems in using an assumed carbon dioxide output for its calculation, its inability to predict the severity of malabsorption and the nature of the dietary load used.

Adolescent↗
PubMed1992

Mobile cardiac catheterization laboratories. Society for Cardiac Angiography and Interventions Laboratory Performance Standards Committee.

The Society of Cardiac Angiography and interventions proposed guidelines for the establishment of mobile cardiac catheterization laboratories. These laboratories should be established only in areas with genuine need, preferably as determined by an objective medical authority. Safety of the patient should be of paramount importance and specifications as to the selection of patients, transportation of patients with complications, the relationship to a tertiary care center, and quality assurance mechanisms are all addressed.

Cardiac Catheterization↗
PubMed1992

Cardiac catheterization laboratory survey: 1990. Society for Cardiac Angiography and Interventions, Laboratory Performance Standards Committee.

A survey of 117 member cardiac catheterization laboratories was undertaken by the Society for Cardiac Angiography and Interventions. The survey included numbers and types of procedures, both diagnostic and interventional, in adult as well as pediatric age groups. Radiation safety, various laboratory policies, frequency of short stay, and outpatient procedures were tabulated. Report generation, training programs, administrative organization, and laboratory equipment were all included. The results were compared with a 1978 survey. Areas of concern in terms of safety of the patient and possible underutilization of laboratories were identified.

Angioplasty, Balloon, Coronary↗
PubMed1992

Facing the cuts: a health authority's experience of rate-capping.

Health and social services in Britain are both publicly funded, but health care is provided centrally by the National Health Service while social services are provided by local government. Central government has sought to limit overall public spending by limiting the income of local authorities from rates (property taxes)--a policy known as rate-capping. In the face of this policy, one inner London local authority was forced to cut its social services budget in 1988/89 by 17%. We have compared the actual social service reductions with the perceptions, expressed in semi-structured interviews, of 69 health and social services staff. There was a perceived deterioration in social service provision, and indicators were suggested which would help health service staff to monitor these changes. There were also recent and more long-standing difficulties of communication between the two services, which limited joint working. The increasing emphasis on community care requires health authorities to cooperate more closely with social services at the local level.

Health Expenditures↗
PubMed1992

Laxative induced diarrhoea--a neglected diagnosis.

A laxative screening service was established and offered to gastroenterologists in hospitals covering the West and Central belt of Scotland. The prevalence of laxative induced diarrhoea was assessed in two populations and was found to be 4% in new patients presenting to a gastroenterology clinic with diarrhoea and 20% in patients already under investigation of chronic idiopathic diarrhoea. A high rate of missed diagnosis of laxative induced diarrhoea (71%) and a low request rate (eight per annum) confirm the low clinical awareness of this diagnosis. We found potential savings of 80% of the cost of investigations subsequently ordered which could have been avoided by performing laxative screens on all patients presenting with diarrhoea. The introduction of such a screening policy is recommended as a cost-effective measure.

Cathartics↗
PubMed1991

Diagnosis of the abuse of magnesium and stimulant laxatives.

A reliable diagnosis of laxative abuse can only be reached by chemical analysis. We report a modified thin layer chromatography approach for the detection and confirmation of over-the-counter colonic stimulant laxatives. Potential interference by dietary and drug components chemically similar to anthraquinones was investigated and the method was found to be specific in this respect. The diagnosis of magnesium laxative abuse is more difficult since magnesium is a component of body fluids. By inducing diarrhoea with magnesium salts in volunteers we have established that the diagnosis can be made by measuring magnesium concentrations in stool water, with 30 mmol/L being an appropriate cut-off concentration.

Cathartics↗
PubMed1990

Trophic control of the ornithine decarboxylase/polyamine system in neonatal rat brain regions: lesions caused by 6-hydroxydopamine produce effects selective for cerebellum.

Norepinephrine has been hypothesized as a trophic factor influencing postnatal development of the cerebellum. In the current study, neonatal rats were given 6-hydroxydopamine (6-OHDA) to destroy noradrenergic projections and the effects on the ornithine decarboxylase (ODC)/polyamine system were evaluated; ODC initiates the synthesis of polyamines, which are known to control cellular development in the cerebellum, and neonatal ODC activity is regulated in part by beta 2-adrenergic receptors. Intracisternal administration of 6-OHDA resulted in complete and permanent depletion of cerebellar norepinephrine and a deficit in ODC, polyamine levels and cerebellar growth. Subcutaneous administration of 6-OHDA, which caused only a small initial reduction in cerebellar norepinephrine, did not affect ODC and had only minor effects on tissue growth. Indeed, levels of the polyamines tended to be elevated after subcutaneous 6-OHDA, associated with postweaning elevations in norepinephrine, results which are probably indicative of axonal regeneration. In contrast to the effects of 6-OHDA on cerebellar development, neither the intracisternal nor subcutaneous drug treatment had any effect on cerebral cortical polyamines or growth, although the intracisternal treatment did impair ODC activity early in development. These data suggest that postnatal noradrenergic input, acting through the ODC/polyamine pathway, plays a selective role in cerebellar development.

Animals↗
PubMed1990

Enalapril in the long-term treatment of elderly hypertensives.

The long-term antihypertensive effects of enalapril were assessed for a period of up to 1 year in 44 elderly patients with mild-to-moderate essential hypertension. Following a 2-week placebo period, patients who were assigned to enalapril were followed for 6 weeks in a randomized clinical trial. In patients who benefited from enalapril, treatment was continued and subjects were followed for up to 1 year. Supine and standing systolic and diastolic blood pressures were significantly reduced throughout the 1-year period compared with baseline. The dosage of enalapril was increased from 10 to 20 mg daily in 12 patients; 8 required additional antihypertensive agents. Enalapril is effective in the long-term treatment of hypertension; no loss of antihypertensive agents. Enalapril is effective in the long-term treatment of hypertension; no loss of antihypertensive effect occurs.

Aged↗
PubMed1990

Clonazepam and imipramine in the treatment of panic attacks: a double-blind comparison of efficacy and side effects.

Data from 12 patients (in two control study groups) provide preliminary results of an ongoing double-blind comparison of clonazepam and imipramine in the treatment of panic disorder. In both treatment groups, the patients' global improvement was substantial over the first few weeks and persisted over the 6-month treatment period based on assessments by the therapist and the patient; side effects were mild. Faintness was slightly more prevalent among patients on clonazepam treatment but disappeared after the first few weeks. Mild, persistent tachycardia was reported among patients receiving imipramine. No tolerance emerged, and discontinuation was successful in 2 patients from each group after 6 months of treatment. Eight patients needed continued medication (25-50 mg/day of imipramine, 0.5-2.0 mg/day of clonazepam) to maintain substantial improvement. Findings confirm earlier reports from open studies that low doses of both drugs eliminate panic attacks (about 50 mg/day for imipramine and 1.5 mg/day for clonazepam).

Adult↗
PubMed1989

A comparative study of conventional and controlled-release formulations of trazodone in elderly depressed patients.

One hundred sixty-six elderly depressed patients were recruited from six hospital centers and entered in a double-blind, randomized, parallel group comparative study of conventional and controlled-release formulations of trazodone. Patients received a single nighttime dose of 100 mg for 1 week, followed by 3 weeks of 200 mg or less, depending upon tolerance. Efficacy was measured using the modified Hamilton depression rating scale and global assessments of the severity of depression and improvement relative to baseline. Both treatments were equally effective with 39 (68%) patients completing 4 weeks of treatment with the conventional formulation and 41 (77%) patients completing 4 weeks treatment with the controlled-release formulation rated as very much improved. Sleep improved shortly after initiation of treatment in most patients and there were no significant differences between groups. There was a tendency for fewer side effects to be recorded during the first week of treatment in patients receiving the controlled-release formulation but no difference reached statistical significance.

Aged↗
PubMed1989

Diagnosis and prevalence of HIV-2 antibodies in different population subsets in The Netherlands.

A serum panel obtained from male homosexuals (n = 278); i.v. drug abusers (n = 99), patients attending a VD clinic (n = 390), blood donors who visited Central or West Africa (n = 573), blood donors who had sexual contact with natives from Central or West Africa (n = 38), blood donors from Surinam, South America (n = 481), individuals positive for anti-HIV-1 (n = 94), individuals with indeterminate HIV-1 western blot (WB) reactions (n = 73), African patients with AIDS or AIDS-related symptoms (n = 30), and random Dutch blood donors (n = 555), was tested with HIV-2 ELISA (ELAVIA-2). Of these 2,611 samples, 32 (1.2%) were repeatedly reactive. Antibodies to gp140/105env were found in 4/32 by HIV-2 WB, and in 1/4 by radioimmunoprecipitation (RIPA). These 4 HIV-2 WB-positive samples were also reactive with gp160/120env in HIV-1 WB, suggesting cross-reactivity. In a spot test with synthetic peptides of the transmembrane glycoprotein of both HIV types, 3/4 were only HIV-1 positive and 1/4 was strongly HIV-2 positive and weakly HIV-1 positive. In inhibition assays with soluble HIV-1 or HIV-2 synthetic peptides in HIV-1 and HIV-2 peptide ELISA, cross-reactivity was excluded, which indicates an HIV variant or HIV-1/HIV-2 double infection. It is concluded that for the moment HIV-2 infection is at low prevalence in risk groups in The Netherlands, and that in addition to WB and RIPA, synthetic peptide assays are useful for differentiation between HIV-1 and HIV-2 antibodies.

Blotting, Western↗