Biomedical subjects
A Macdonald
Publications and source records attributed to A Macdonald.
Ambulatory manometric examination in patients with a colonic J pouch and in normal controls.
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Pasteurella multocida infection in continuous ambulatory peritoneal dialysis.
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Mental disorder in an elderly home care population: associations with health and social service use.
BACKGROUND: Home care services maintain people in their own households by providing practical help such as with housework, shopping and personal care. In this study associations between mental disorder and health and social service use, demographics and activity limitation are investigated. METHOD: A cross-sectional study with random cluster sampling of people over 65 receiving home care in Lewisham. Mental disorder was rated using the GMS/AGECAT system. RESULTS: We interviewed 169/177 eligible individuals, a response rate of 96%. Forty-six percent of this population were rated as cases of mental disorder (15% organic and 26% depressive). Most (84%) of those with depression did not appear to be receiving appropriate treatment. Home care provision to those with depression (unlike dementia) was only partially explicable in terms of activity limitation. CONCLUSIONS: There is a high level of depressive disorder in this population with little in the way of appropriate primary or secondary care management. Those in sheltered housing seem particularly at risk; depression may lead to increased service use independent of disability.
Teledermatology in the Highlands of Scotland.
A pilot study of telemedicine consultations of 51 dermatology patients showed that the technology worked well, with the diagnosis being able to be made in most patients and over half of the patients being able to be dealt with through this medium only. It could therefore have a valuable screening role. However, many of the patients, in spite of the obvious advantage of an immediate consultant opinion, felt it would be more appropriately used as a review technique.
Quantitation of vitamin E and a carotenoid pigment in cataractous human lenses, and the effect of a dietary supplement.
The quantitation of tocopherols and carotenoids in lipid extracts of cataractous human lenses was performed in parallel with those of matched samples of plasma, which was also analysed at the same time. Alpha-tocopherol in cataractous lenses from elderly human subjects was present at 4.4 mumoles/kg wet weight, much less than the mean of 33 mumoles/l in plasma from these subjects. The mean ratio of alpha- and gamma-tocopherols was 3.5 in the lenses, and 11.3 in plasma. Lens extracts contained no detectable alpha- or beta-carotene, lycopene, or beta-cryptoxanthin. However, all the lens extracts contained a pigment with the retention time and spectrum of lutein and zeaxanthin. Using the molar extinction coefficient of lutein this was present at ca. 0.03 microM, compared with 0.2 microM in plasma. Seven patients with bilateral cataracts had one of their cataractous lenses removed and analysed, and were then given either an oral placebo, or an oral supplement of ascorbate, alpha-tocopherol and beta-carotene. Three months later, the second cataractous lens, and a blood sample, were analysed. Three of the seven had received the active supplement, as confirmed by substantially raised blood levels of alpha-tocopherol and beta-carotene, and raised aqueous humour levels of vitamin C. However, lens tocopherol levels remained unchanged, and no beta-carotene could be detected in the lenses after supplementation. This preliminary evidence needs to be confirmed in larger studies.
Inadequacies in Health Recommendations.
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Long-term nutrient enrichment of an estuarine system: Ythan, Scotland (1958-1993).
A comprehensive review is given of past and current annually averaged nutrient concentrations (total oxidised nitrogen [TON], phosphate and silicate) in the River Ythan and its estuary. TON concentrations in the River Ythan have increased from ca 100-150 microm in the late 1960s to ca 500-550 microm in the early 1990s, changes which are also shown in the estuary. The interpretation of the phosphate data is more complex but concentrations in the estuary also appear to have increased. Silicate concentrations have remained constant with time. The results of 11 surveys of the estuary completed during 1993 are given. TON and silicate behave conservatively in the estuary, with concentrations determined by those of the fresh water end-member and hence by processes within the catchment. Phosphate and ammonia concentrations at low salinity are affected by the discharge from the Ellon sewage treatment facility at the head of the estuary. Throughout the estuary there is evidence of an input of ammonia to the water column from the sediments, but it represents only ca 0.2-2% of the nitrogen entering from the River Ythan. Despite the increased nutrient loading to the estuary there is no evidence that this has resulted in higher chlorophyll concentrations in the water column, this observation is attributed to the relatively short flushing period of the estuary.
Characterization of a small supernumerary ring X chromosome by fluorescence in situ hybridization.
We report on a male with mild learning disabilities who has a supernumerary marker chromosome. The marker chromosome was defined by fluorescence in situ hybridization as a ring X chromosome with breakpoints in the juxacentromeric region. Replication studies suggest that the ring X is late-replicating. However XIST, a gene in the X inactivation centre interval which is expressed exclusively from the inactive X chromosome, is not present on the marker, nor is it expressed in the patient's cells. These results are discussed with respect to karyotype-phenotype correlations and X inactivation.
Psychiatric services for elderly people. Traditional model has limited scope.
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An evaluation of the multidisciplinary approach to psychiatric diagnosis in elderly people.
OBJECTIVE: To determine the accuracy of psychiatric diagnoses made by two community psychogeriatric teams operating a multidisciplinary assessment procedure. DESIGN: Comparison of team diagnosis with independent formal assessment and consensus diagnosis by research psychiatrists. SETTING: Two community psychogeriatric teams with similar operational policies in an inner London health district. SUBJECTS: 100 people aged 65-90 (70 women) newly referred to the teams. MAIN OUTCOME MEASURES: Concordance between team and research diagnoses. RESULTS: Agreement between team and research diagnoses ranged from 90% to 99% for the specific psychiatric disorders studied. There was no significant difference between medical and non-medical team members in their diagnostic performance compared with the research psychiatrists. Increased diagnostic accuracy by team members was associated with longer experience of team working, regardless of the team members' professional background. CONCLUSIONS: The multidisciplinary approach to the assessment of referrals to these community teams for the elderly is not associated with misdiagnosis of psychiatric disorder.
The myth of suicide prevention by general practitioners.
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Randomized placebo-controlled trials of antibiotics for acute bronchitis: a critical review of the literature.
BACKGROUND: Acute bronchitis is a common clinical problem that causes considerable morbidity and presents both diagnostic and treatment dilemmas for the physician. An evaluation of all published randomized controlled trials of antibiotics in the treatment of acute bronchitis was conducted to (1) quantitatively assess methodologic rigor, (2) determine if effectiveness of antimicrobial therapy is known, and (3) analyze strengths and weaknesses of randomized controlled trials in family practice settings. METHODS: A scoring system for the evaluation of randomized controlled trials was adapted for this study. Four raters, who were blinded to which journals published the studies and the type of antibiotic used in each study, assessed the six-randomized clinical trials for treatment of bronchitis identified through a literature search. The trials were rated according to criteria that measured internal validity. RESULTS: Scores for internal validity ranged from 65.5 to 102.5 points with a maximum possible score of 120 points (54.6% to 85.4%). The two trials with the highest scores assessed doxycycline and showed no benefit from use of this antibiotic. Single trials that studied erythromycin and trimethoprim-sulfamethoxazole showed improvement in outcome from use of these drugs; however, of the six trials, these two studies ranked fourth and fifth for internal validity. Low scores resulted from small sample size, possible contamination with other treatment measures, and poor assessment of subjects' compliance with antibiotic regimen. CONCLUSIONS: An evaluation of the current literature does not support antibiotic treatment for acute bronchitis. Further studies of this common illness are indicated. It is hoped that this critical review of randomized control trials will prove useful in the planning of future studies, in placing greater emphasis on methodologic rigor, and in giving greater consideration to the practical constraints of research in the family practice setting.
Relaxant effects of alpha-adrenoceptor agonists in the rat isolated gastric fundus.
In rat gastric fundus preparations with tone raised by the addition of barium chloride or carbachol, and in the presence of propranolol (2 microM) to prevent beta-adrenoceptor mediated effects, the adrenoceptor agonists noradrenaline, adrenaline, alpha-methylnoradrenaline, isoprenaline, cirazoline and phenylephrine all caused concentration-related relaxant responses. Relaxations to the catecholamines were poorly antagonized by prazosin (0.01-1 microM) resulting in the slopes of Schild plots being less than unity, low pA2 values for prazosin against the catecholamines and a clear relaxant effect of the catecholamines even in the presence of 1 microM prazosin. The prazosin-resistant relaxations were unaffected by higher concentrations of prazosin (2 microM) and propranolol (30 microM) or by further additions of idazoxan (1 microM) or haloperidol (30 microM). The relaxations were not due to a non-specific effect of the catechol nucleus since neither dihydroxyphenylethylene glycol (DOPEG) nor dihydroxyphenylacetic acid (DOPAC) produced relaxant effects at concentrations up to 300 microM. In contrast to the results with the catecholamines, prazosin was a potent antagonist of the relaxant effect of cirazoline and phenylephrine, although the antagonism was difficult to quantify due to a lowering of the slope of the concentration response curves to cirazoline and phenylephrine with the higher concentrations of prazosin (0.1 and 1.0 microM). In conclusion postjunctional relaxatory effects of catecholamines in the rat gastric fundus are mediated partly via alpha 1-adrenoceptors and partly via an atypical adrenoceptor.