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Biomedical subjects

J H Alpers

Publications and source records attributed to J H Alpers.

At least 19 recordsLinked to original sources
PubMed1992

A profile of respiratory symptoms in urban and rural South Australian school children.

This report describes the cross-sectional analyses of data from the first year of a longitudinal study using questionnaire and respiratory function data over a 5 year period from a sample of rural South Australian school children. The cumulative or lifetime prevalences of respiratory symptoms were estimated in 825 rural and 1261 urban school children aged between 5 and 15 years in order to determine if the prevalence rates differed between rural and urban school children. The study found the overall cumulative prevalence of asthma and/or wheezy breathing (AWB) to be 24.1% in the rural school children compared to 27.6% in the urban school children. Most children developed AWB symptoms before the age of 7 years, with 20% reporting moderately severe symptoms and 10% having more than one attack per fortnight. The cumulative prevalence of bronchitis, loose/rattly cough (BLRC) differed significantly between the rural school children (34.1%) and urban school children (47.9%). The BLRC symptoms preceded the development of AWB in many cases. Urban school children also reported a higher prevalence of atopic conditions.

Adolescent↗
PubMed1991

Home oxygen therapy: an audit of survival.

A retrospective audit of the medical records and respiratory function data of 186 subjects placed on long term continuous home oxygen therapy between 1979 and 1988 was undertaken. Kaplan-Meier survival curves were constructed for subjects with Chronic Obstructive Airways Disease (COAD) and Interstitial Lung Disease (ILD). There was an almost twofold greater mortality rate for COAD subjects at 12 months when compared to the Medical Research Council Working Party (MRC) and the Nocturnal Oxygen Therapy multicentre clinical trials (NOTT). However, the mean values of the baseline physiological parameters were similar to these major studies of long term oxygen therapy. Survival of ILD patients was significantly less than COAD patients (p less than 0.001). Within both disease categories, females survived significantly longer than males. Within the COAD category the observed sex difference was not abolished when the data was controlled for age, Pco2, Po2 and pack-years (as an estimate of total cigarette consumption). However, prior smoking history appeared to modify the male-female difference in COAD survival. These are the first Australian survivorship data for patients on long term oxygen therapy. The more adverse survival figures compared with the overseas studies may reflect the co-existence of other diseases.

Aged↗
PubMed1990

Bronchial hyperresponsiveness in two populations of South Australian rural schoolchildren.

This report describes the cross-sectional analyses of the results obtained from the first year of a longitudinal study designed to investigate the natural history of bronchial hyperresponsiveness in association with reported respiratory symptoms in children attending the Burra and Kingston Community Schools. Bronchial hyperresponsiveness to methacholine was measured using a modified Yan technique. Prevalence rates of respiratory symptoms were obtained using the Tasmanian Asthma Foundation Questionnaire. Considerable overlap of reported symptoms of asthma and/or wheezy breathing and bronchitis and/or loose and productive cough was observed suggesting that a clear distinction between such symptoms in childhood may not be possible. Analyses of data showed the prevalence of reactive airways in children to be 21.3% in Burra and 22.0% in Kingston. These values were the same as results obtained from an earlier pilot study in Burra and similar to results from Wagga Wagga (19.6%) and Auckland (20.1%) but higher than from Belmont (15.5%) and Villawood (15.3%). Increased bronchial hyperresponsiveness was associated with the reporting of symptoms of asthma and/or wheezy breathing (odds ratio, 5.04; 95% confidence interval, 2.18-11.74) and bronchitis and/or loose and productive cough (odds ratio, 2.28; 95% confidence interval, 1.02-5.13), at any time in the child's life. Of children with no reported symptoms 10% also had demonstrable bronchial hyperresponsiveness.

Asthma↗
PubMed1988

Biochemical studies of N-methyltransferase in human and guinea-pig lung: no apparent role in the pathogenesis of asthma.

1. N-Methyltransferase activity was measured in surgical specimens of human lung using phenylethanolamine as substrate. Thirty-three male and seven female patients, age range 19-78 (median 62.5) years were studied. The activity in lung homogenates was 0.59 x 10(-6) units/mg of protein (SEM 0.03, n = 40), with a range of 0.16-1.16 x 10(-6) units/mg of protein. There was no difference (P = 0.97) in activity between males and females. 2. Non-specific N-methyltransferase activity was estimated in 17 of the surgical specimens using beta-phenylethylamine as substrate. This activity was 38.9% (SEM 5.3) of that with phenylethanolamine. Comparative studies with rabbit lung, which has a well-characterized non-specific N-methyltransferase, showed significant differences in substrate specificity between the two species. 3. The apparent Km and Vmax for phenylethanolamine in seven human lung homogenates was 22.0 (SEM 4.6).mmol/l and 1.82 x 10(-6) units/mg of protein (SEM 0.36). The noradrenaline N-methyltransferase (NMT; EC 2.1.1.28) inhibitors SKF 64139-A and LY 134046 did not inhibit this activity up to a concentration of 100 mumol/l. This activity was inhibited 51.4% (SEM 8.6, n = 6) by 100 mumol/l S-adenosyl-L-homocysteine. Immunohistochemistry did not reveal immunoreactive NMT in human lung sections. 4. Comparative studies with guinea-pig lung homogenates demonstrated non-specific N-methyltransferase activity in this species which is similar to the human lung.(ABSTRACT TRUNCATED AT 250 WORDS)

2-Hydroxyphenethylamine↗
PubMed1987

Psychiatric morbidity in patients with chronic airflow obstruction.

Fifty consecutive patients with chronic airflow obstruction who were admitted to a respiratory unit were assessed medically and psychiatrically. A high rate of psychiatric morbidity (58%) was detected with panic and other anxiety disorders (34%) being particularly prevalent. Various physiological and psychological reasons for the high rate of anxiety disorders are discussed.

Adult↗
PubMed1987

Combined bronchodilator protection against histamine-induced bronchoconstriction in man.

Sixteen stable asthmatics had the protective effects of inhaled fenoterol (200 micrograms) and inhaled ipratropium bromide (60 micrograms) against standardized histamine inhalation tests at 1 h examined in a randomized double blind fashion. There was no significant difference in the baseline forced expired volume in 1 s (FEV1) for the two study days (P greater than 0.05). There was an increase in FEV1 at 1 h on the fenoterol and ipratropium day compared with the fenoterol day (0.26 versus 0.17 l; P less than 0.05). The geometric mean provocative concentration of histamine to cause a 20% fall in FEV1 (PC20) was 6.31 mg/ml after fenoterol and 8.51 mg/ml after fenoterol and ipratropium (P = 0.038). There was no significant relationship between bronchodilator effect of the bronchodilators and the increase in PC20 from pre-study values, r = 0.307 (P = 0.25) for fenoterol alone and r = 0.195 (P = 0.47) for fenoterol and ipratropium. The relationship between pre-study histamine responsiveness and the increase in PC20 caused by the bronchodilators just failed to reach statistical significance, r = -0.441 (P = 0.09) for fenoterol alone and r = -0.47 (P = 0.06) for fenoterol and ipratropium. The study has shown a greater right shift of histamine responsiveness for combined inhaled fenoterol and ipratropium compared with inhaled fenoterol alone in this group of asthmatics.

Adult↗
PubMed1987

The efficacy of nedocromil sodium (Tilade) in asthma.

Nedocromil sodium is a new antiasthmatic drug with properties similar to sodium cromoglycate. We examined the efficacy of nedocromil sodium compared to placebo in 71 asthmatic patients in a three-centre double-blind parallel group study over 12 weeks. During the study the patients' maintenance inhaled corticosteroids were progressively withdrawn. Nedocromil sodium had an advantage over placebo in the number of withdrawals related to uncontrolled asthma, 14 and 24 respectively (p = 0.03). Changes in symptom scores, peak flow rates and bronchodilator use favoured nedocromil sodium occasionally during the study. The unusual taste of the active drug was reported frequently. Nedocromil sodium is more efficacious than placebo in asthma maintenance, but does not replace inhaled corticosteroids.

Administration, Inhalation↗
PubMed1986

The effect of bucindolol on the airway function of asthmatics.

The airway and cardiovascular effects of separate single oral doses of 50, 100 and 200 mg of bucindolol were compared to those of placebo in a double-blind trial in 16 patients with mild to moderately severe asthma. Heart rate (HR), blood pressure (BP), forced vital capacity (FVC), forced expired volume in one second (FEV1), maximum expiratory flow at 50% of vital capacity (FEF50) and maximum expiratory flow at 75% of expired vital capacity (FEF75) were measured before and at intervals for 4h, when salbutamol (200 micrograms) was inhaled and the measurements repeated 15 min later. There was an interval of at least 4 days between each drug treatment day. Four of the 16 patients developed clinically significant bronchoconstriction with 50 mg (3) or 100 mg (1) of bucindolol and were withdrawn from the study. The remaining patients showed impaired bronchodilator response to salbutamol for each bucindolol dose as compared to placebo. No significant BP or HR effects were measured. Two patients withdrew because of circumstances unrelated to bucindolol induced bronchoconstriction. The development of bucindolol induced bronchoconstriction in this group of mild to moderate asthmatics was not predicted by the level of baseline pulmonary function, or the level of histamine responsiveness. However, there was a weak relationship between bucindolol induced bronchoconstriction and salbutamol induced bronchodilation. There are no definitive asthmatic characteristic to predict the likelihood of significant bucindolol induced bronchoconstriction in this asthmatic population.

Adult↗
PubMed1986

The prevalence rate of respiratory symptoms in school children from two South Australian rural communities.

The respiratory symptoms and respiratory function of 680 schoolchildren from two rural area of South Australia were studied. The initial results of this prospective, longitudinal study showed that the cumulative prevalence of asthma and/or wheezy breathing was 27.4% in the Burra population and 23.1% in the Kingston population. The cumulative prevalence of one or more attacks of asthma/wheezy breathing amongst Burra (38.8%) and Kingston (23%) children aged up to 8 years was significantly higher than that reported for urban Melbourne children (11%, p less than 0.01). The combined South Australian group reported a cumulative prevalence of asthma/wheezy breathing alone of 10% which was significantly higher than the cumulative prevalence rates in three previous studies reported in Australia (1.8%, 2.6%, 2.7%, p less than 0.01). The highest overall cumulative prevalence of bronchitis/loose or productive cough occurred in the 12 year old Burra children (41.5%). Burra girls had the highest prevalence of bronchitis/loose or productive cough (36.8%) compared to other groups studied at both locations. The parental smoking rate (60.4% in Burra, 57.4% in Kingston) is much higher than the national figure reported by the Bureau of Statistics in 1977 (35.9%). The prevalence of asthma/wheezy breathing is much higher in the South Australian cohort compared to the Queensland and Tasmanian cohorts studied using the same questionnaire. Predicted respiratory function parameters using initial algorithms are similar to those reported for urban Australian children.

Adolescent↗
PubMed1986

A 4-week Australian multicentre study of nedocromil sodium in asthmatic patients.

The use of nedocromil sodium 4 mg q.i.d. in asthmatics with mildly unstable asthma induced by a reduction of their inhaled beclomethasone dipropionate dose was investigated in a double-blind, parallel group, placebo-controlled study. Compared with placebo, nedocromil sodium improved night-time and daytime asthma score, night-time and daytime bronchodilator use, and evening PEFR at some stage during the 4-week treatment. It is concluded that nedocromil sodium exerts a beneficial effect in chronic asthma.

Adolescent↗
PubMed1979

Bronchial reactivity in Western red cedar induced asthma.

A patient with Western red cedar induced asthma is described. The diagnosis was confirmed by a bronchial challenge with Western red cedar saw dust and the subsequent prolonged bronchial reactivity changes were measured using histamine inhalation tests.

Asthma↗
PubMed1978

Arterial blood gas analysis: potential errors due to the addition of heparin.

The effect of sodium heparin on the determination of the major arterial blood gas parameters was studied. The addition of heparin produced errors in all three parameters tested, i.e. PO2, PCO2 and pH. The PCO2 determination was most affected, a 12% decrease being introduced into a 1.5 ml blood sample by the volume of heparin which fills the deadspace of a syringe and needle. Small but statistically significant errors were also produced in PO2 and pH by this heparin concentration. The clinical implications of these findings are discussed and certain measures outlined to avoid such errors.

Arteries↗