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Biomedical subjects

M W Burns

Publications and source records attributed to M W Burns.

At least 37 records · Page 2Linked to original sources
PubMed1990

Urodynamic studies in children who wet.

The value of urodynamic evaluation was assessed in children with diurnal and/or nocturnal enuresis without overt obstruction or neuropathy. The hypothesis that children with bladder instability and dysfunctional voiding represent 2 separate populations was also examined. A simplified urodynamic method was used to evaluate 191 children and they were divided into 3 groups: 64 had normal bladders which were stable during filling and voiding was co-ordinated and complete; 97 had unstable bladders but voiding was normal and co-ordinated; 30 had dyssynergic voiding and an increased volume of residual urine. The urodynamic evaluations were helpful in distinguishing the large number of children with normal findings in whom the problem was motivational. The children with unstable bladders had a physiological abnormality due to delayed maturation and in these cases anticholinergic and musculotrophic agents were usually helpful. The dysfunctional voiders had serious behavioural problems, were difficult to treat, and often required a multidisciplinary approach. These data indicate that there are indeed 2 distinct groups: 1 with instability alone and 1 with dysfunctional voiding with or without instability. Although infection and/or reflux are common in the former, the more devastating urinary tract changes, particularly heavy trabeculation and elongation of the bladder, occur in the latter group.

Child↗
PubMed1989

Studies of polyglycolic acid hollow self-retaining vasal stent in vasovasostomy.

A simple method of vasovasostomy using a unique hollow, biflanged, hydrolyzable, self-retaining intraluminal stent made of polyglycolic acid (PGA) was evaluated in rat and dog animal models. The stented vasovasostomy was compared with a modified two-layer technique in a randomized prospective trial in rats. Twenty of 22 vasovasostomies using the 0.8890 mm and 0.9398 mm stents were patent, whereas only 4 of 22 vasovasostomies using a modified two-layer anastomosis without a stent were patent (P less than 0.01). Eight dogs underwent implantation of the absorbable vasovasostomy stent on one side and two-layer vasovasostomy on the other. Scanning electron microscopy showed superior re-epithelialization and closer return to normal morphology in the stented vasovasostomies than with the conventional two-layer technique.

Animals↗
PubMed1989

Urinary excretion of C5b-9 reflects disease activity in passive Heymann nephritis.

Passive Heymann nephritis (PHN) is a model of membranous nephropathy in rats in which glomerular injury is mediated by the terminal C5b-9 membrane attack complex of complement. This model has been shown to be associated with markedly elevated urinary excretion of C5b-9, compared to other experimental models of glomerulonephritis To determine if urinary C5b-9 excretion could serve as an index of disease activity by correlating with the formation and quantity of glomerular subepithelial immune deposits in PHN, we measured urinary excretion of C5b-9 in PHN under several experimental conditions. In the heterologous phase a direct correlation was demonstrated between levels of urinary C5b-9 excretion and the amount of anti-Fx1A IgG deposited in glomeruli (r = 0.85). In the autologous phase, C5b-9 excretion correlated with the amount of deposit forming antibody present in the serum and resolved when antibody disappeared, despite persistence of glomerular deposits of antigen, antibody, C5b-9 and heavy proteinuria. Glomerular C3 deposits paralleled urinary C5b-9 excretion. Re-initiation of active deposit formation by a second injection of anti-Fx1A produced new C3 deposits and a marked rise in C5b-9 excretion. Finally, complete abrogation of deposit formation by transplanting PHN kidneys into normal recipients also halted C5b-9 excretion. Our findings demonstrate that urinary excretion of C5b-9 is a sensitive index of on-going immunologic disease activity in the PHN model of membranous nephropathy.

Animals↗
PubMed1987

Pediatric urinary tract infection. Diagnosis, classification, and significance.

The initial task is to establish the diagnosis of a urinary tract infection. The clinical setting, method of specimen collection, bacterial colony count, and species are all important considerations. Next, the infection is classified as complicated or uncomplicated. Complicated infections require hospitalization and parenteral antibiotic therapy. Appropriate imaging studies are imperative to determine whether urologic intervention is necessary. All children with well-documented urinary tract infections deserve diagnostic evaluation, regardless of sex or presence of systemic symptoms.

Adolescent↗
PubMed1983

Cerebral abscess: manifestation of pulmonary arteriovenous malformations.

Two cases in which cerebral abscess was the initial presenting feature of pulmonary arteriovenous malformations are reported. Cerebral abscess recurred in one patient. The pulmonary malformations were multiple and bilateral in both cases. One patient had associated features of hereditary hemorrhagic telangiectasia. Surgical resection of the largest malformations was performed in both cases. Cerebral abscess did not recur in either case post-operatively, though this may not have been due to surgical intervention.

Adult↗
PubMed1977

Medical-surgical differences in hospital stress factors.

Psychosocial stress due to the experience of hospitalization was ascertained for 535 medical and surgical patients in a community hospital, using a Hospital Stress Rating Scale, Medical-surgical differences along nine dimensions of stress as measured by this scale were examined, using analysis of covariance to control for the effects of patient characteristics known to be associated with scores on the Hospital Stress Rating Scale. The controlled variables were age, education, number of previous hospitalizations, number of years since last hospitalization, and seriousness of illness (Seriousness of Illness Rating Scale). The analysis of covariance results indicated higher perceived stress for surgical patients on the dimensions of unfamiliarity of surroundings, loss of independence, and threat of severe illness. Medical patients scored higher on the dimensions of stress due to financial problems and lack of information. The authors discuss how these findings might be incorporated in experimental studies designed to reduce stress among hospital patients.

Awareness↗
PubMed1976

Pneumonia in a city hospital.

Of 222 patients with pneumonia in St Vincent's Hospital, Sydney, in 1972, more were affected by bronchopneumonia (53%) than lobar pneumonia (46%). Two-thirds of the patients were males and 86% were aged 40 years or more. Only 59% had any bacteriological studies performed. It was unusual to isolate pathogens from persons who had received antibiotics before cultures were taken, but of cultures taken from persons not receiving antibiotics, 65% yielded pneumococci. Infections due to Staphylococcus aureus, pseudomonas and enterobacteria were uncommon. Haemophilus influenzae appeared to be a co-pathogen in bronchopneumonia more than in lobar pneumonia. The mortality in lobar pneumonia was acceptably low (4%), but was generally high in bronchopneumonia, being 32% when the condition occurred after surgical operations and 35% when this form of pneumonia complicated other normally non-terminal medical diseases. The mortality was 17% in primary bronchopneumonia.

Adult↗
PubMed1976

Skin-prick test reactions to inhalant allergens in asthmatic patients.

Skin-prick tests with extracts of a large number of inhalant allergens were carried out on 489 asthmatic patients attending the thoracic outpatient clinics at two Sydney hospitals. Positive reactions, which had been previously found to be invariably accompanied by bronchial immediate allergic reactivity, occurred in 98% of patients who had had symptoms of asthma since the first decade of life, and in 28% of those whose symptoms did not begin until after the age of 60 years. Prick-test reactions were most commonly produced by house dust and house dust mite (70%), followed by grass pollens (50%), moulds (30%), weed pollens (35%) and tree pollens (22%). The patients commonly gave positive reactions to two or more of the extracts from within each of those allergen groups.

Adolescent↗
PubMed1976

The relationship between bronchial histamine reactivity and atopic status.

It has been proposed that increased production of IgE, a feature of atopy, is a cause of the non-specific bronchial hyper-reactivity that is characterisitc of asthma. This hypothesis was examined by selecting groups of subjects with asthma or rhinitis and a group of healthy control subjects and studying the relationship between their bronchial histamine reactivity and their atopic status. In none of the groups tested was there a significant association between the degree of bronchial histamine reactivity and either the serum level of total IgE or the number of extracts of aeroallergens giving positive prick test reactions.

Asthma↗
PubMed1976

Bronchial histamine reactivity: its relationship to the reactivity of the bronchi to allergens.

The aim of this study was to examine the proposal that the magnitude of the response of the bronchi to an immediate allergic reaction depends not only on the degree of sensitization of the bronchi by allergen specific IgE antibody but also on the reactivity of the bronchi to the vasoactive mediators which are released during immediate allergic reactions. This was done by determining the bronchial reactivity to Dermatophagoides pteronyssinus and to histamine of both symptomatic and asymptomatic groups of atopic subjects who had comparable serum levels of D. pteronyssinus specific IgE. Positive bronchial responses to the D. pteronyssinus extract were recorded with both the symptomatic and asymptomatic subjects, the mean bronchial threshold dose of allergen being significantly higher in the asymptomatic than in the asthmatic patients. There was a highly significant correlation between the serum level of allergen specific IgE and the bronchial threshold dose of allergen extract and also between the bronchial threshold dose of allergen extract and of histamine in all groups of subjects. The ability to predict bronchial reactivity to the allergen from the serum level of allergen specific IgE within each group was significantly better if the bronchial reactivity to histamine was included in the correlation analysis. This supports the hypothesis that whether a particular subject who is producing specific IgE antibody will develop symptoms on the inhalation of that allergen depends not only on the amount of allergen which he inhales and on the degree of sensitization of his bronchi but also on the reactivity of his bronchi to the vasoactive mediators which are released by allergen-IgE interaction.

Administration, Intranasal↗
PubMed1975

Identification of IgG antibody as a carrier of reaginic activity in asthmatic patients.

In a previous study it was reported that a group of asthmatic patients, in whom cromolyn sodium did not inhibit bronchial immediate allergic reactions, had reaginic antibodies that did not appear to belong to the IgE class. This study was designed to extend these observations, and it was shown that the IgG fractions from these patients' sera, purified by ion exchange chromatography and specific immunosorbents, had skin-sensitizing activity to the antigen studied, while the IgE fractions did not. The skin-sensitizing activity in the IgG fractions was not removed by anti-IgE antiserum and was not inactivated by heating at 56 degrees C or by reduction/alkylation. It is proposed that IgG antibodies may mediate immediate allergic reactions in some asthmatic patients, that these patients can be detected by means of serum total IgE and allergen-specific IgE estimation, and that cromolyn sodium is not an effective inhibitor of bronchial immediate allergic reactions in these patients.

Adult↗
PubMed1975

The correlation between skin tests, bronchial provocation tests and the serum level of IgE specific for common allergens in patients with asthma.

Cutaneous and bronchial immediate allergic reactivity and the serum level of IgE specific for each of four common inhalant allergens were determined for 153 asthmatic patients. Positive bronchial reactivity to an extract was not detected in any of the patients with a negative prick test reaction to that extract but did occur in 9% of the patients in whom the serum tests results for IgE specific to that allergen fell within the range regarded as negative. Highly significant correlation coefficients between the degree of bronchial and cutaneous allergic reactivity to the allergen extracts were found and these were slightly but significantly less than the correlation between the serum level of allergen specific IgE and the degree of bronchial allergic reactivity to the allergen extracts. These findings indicate that the results both of prick testing with appropriate extracts and estimation of the serum level of allergen specific IgE can be used to predict not only the presence of detectable bronchial reactivity to inhalant allergens but also the degree of this reactivity. However, for the routine investigation of asthmatic patients measurement of the serum level of allergen specific. IgE would appear to have little advantage over properly performed prick tests.

Aerosols↗