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Biomedical subjects

A C Harrison

Publications and source records attributed to A C Harrison.

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

Anaerobic threshold alterations caused by interval training in 11-year-olds.

The purpose of this study was to examine the effects of the interval training on metabolic parameters at maximal work and at the anaerobic threshold in 11 year olds. The subjects were five healthy male children. They trained outdoor for 50 min a day, five times a week for six weeks, using interval work at 25 and 50% above their anaerobic threshold. Before and after training program, they performed a progressive exercise test on a cycle ergometer. During the last 15 sec of each power output measurements were made of oxygen uptake (VO2), carbon dioxide output (VCO2), heart rate (HR), ventilation (VE), ventilatory equivalent for oxygen (VEO2) and ventilatory equivalent for carbon dioxide VECO2). Following training, the group increased their anaerobic threshold (expressed as %VO2max) significantly (P less than 0.05) during the progressive exercise test, by 22%. Also at the anaerobic threshold level, increases were observed following training in CO2 output (VCO2-AT) and respiratory exchange ratio (R). Oxygen uptake (VO2, l.min-1) was increased by 19%, but the difference was not significant (P greater than 0.05). Maximal ventilatory equivalent for (VECO2max) decreased significantly (P less than 0.05). Maximal heart rate was reduced significantly (P less than 0.05). We conclude that training led to an increase of both anaerobic and aerobic metabolism, at any submaximal work above the anaerobic threshold, for this specific age group.

Anaerobic Threshold↗
PubMed1989

Socioeconomic status in childhood asthma.

This study examines the relationship between socioeconomic status (SES) and asthma prevalence and the use of asthma medication. One thousand and fifty European children aged eight and nine years were studied by parent completed questionnaire and histamine inhalation challenge. After controlling for sex of the child and for smokers in the house there were significantly higher lifetime (P = 0.029) and current (P = 0.046) prevalence rates of wheeze in children in low SES groups. There was no relationship between SES and asthma diagnosis, bronchial hyperresponsiveness (BHR: PD20 less than 7.8 mumol), or any combination of BHR with symptoms or diagnosis. The use of bronchodilators and asthma prophylactic drugs was less frequent in the low SES groups of children with wheeze in the last 12 months both with concurrent BHR or irrespective of BHR than in those in high SES groups.

Asthma↗
PubMed1989

Ethnic differences in prevalence of asthma symptoms and bronchial hyperresponsiveness in New Zealand schoolchildren.

Maoris and Pacific Islanders in New Zealand have a higher asthma mortality and hospital admission rates than Europeans. To determine whether difference in asthma prevalence is the major factor underlying these differences in mortality, 2053 Auckland children aged 7-10 years (European 1084, Maori 509, Pacific Islander 460) were randomly sampled from school classes in the Auckland Urban Area, and studied by questionnaire (completed by parents) and histamine inhalation challenge to assess the provocative dose of histamine causing a 20% fall in FEV1 (PD20). Maoris had the highest prevalence rates of respiratory symptoms, and Europeans had rates similar to Pacific Islanders. For "any current wheeze" for example, the prevalence in Maoris was 22.2% compared with 16.1% and 16.3% in the Europeans and Pacific Islanders. The prevalence of diagnosed asthma was similar in the three groups. When bronchial hyperresponsiveness (defined as a PD20 less than or equal to 7.8 mumol histamine) was considered, Europeans had the highest rates (20%), followed by Maoris (13%), and then Pacific Islanders (8.7%). These differences were not accounted for by differences in socioeconomic status, rates of smoking in the home, age, gender, or height. It is concluded that differences in asthma prevalence do not satisfactorily explain the mortality and admission rate differences, although the higher symptom prevalence in the Maoris could be relevant to the higher mortality rate. Maori and Pacific Island children with symptoms of asthma were less likely to be taking prophylactic medication than European children. It is proposed that differences in management are important factors relevant to the increased mortality and morbidity from asthma in Polynesians.

Asthma↗
PubMed1988

International comparison of the prevalence of asthma symptoms and bronchial hyperresponsiveness.

Potential explanations for the higher rates of asthma mortality and hospital admissions in New Zealand (NZ) include greater prevalence of asthma. To evaluate this further, a large community survey has been undertaken. Rates of respiratory symptoms and bronchial hyperresponsiveness (BHR) for children in Auckland, NZ have been compared to those for children in two locations in New South Wales (NSW), Australia: Wagga Wagga (inland) and Belmont (coastal). The methodology used was the same in both studies: parent-completed questionnaire and BHR measured by response to an abbreviated histamine challenge. In Auckland, 1,084 children participated (84% of those selected) and were compared to 769 inland NSW and 718 coastal NSW children. The prevalence of respiratory symptoms, BHR, severity of BHR, and BHR combined with symptoms was similar among Auckland and inland NSW children but lower among coastal NSW children than those from the other two sites. It is concluded that other unidentified factors must be invoked to explain mortality and admission differences between these regions.

Asthma↗
PubMed1987

Control of nosocomial tuberculosis in New Zealand: a window into hospital occupational health?

A survey of six New Zealand hospitals, each of which employs at least one respiratory physician, demonstrated lack of uniformity and several deficiencies in measures to prevent nosocomial tuberculosis. Preemployment screening measures in particular were frequently suboptimal. Suggested improvements include upgrading tuberculosis control policies at a national level, with input from hospital boards, clinicians, and the Department of Health. Future policy changes should be based upon local and national experience and this requires the auditing of hospital control measures. The number of health workers amongst new cases of tuberculosis should also be recorded and taken into account.

Cross Infection↗
PubMed1987

Inhaled high-dose beclomethasone in chronic asthma.

The effects of high-dose inhaled beclomethasone dipropionate were studied retrospectively in 123 asthma patients who were inadequately controlled on standard doses of beclomethasone dipropionate, or who required oral corticosteroids to control their asthma. High-dose beclomethasone dipropionate was administered by aerosol which delivered 250 micrograms beclomethasone dipropionate per metered dose. Thirty-one percent of the steroid-dependent patients (n = 65) were able to stop maintenance oral steroid after the introduction of beclomethasone dipropionate 250 and a further 48% were able to reduce their daily dosage. The mean reduction in daily maintenance prednisone was 5.2 mg. Comparing a six month period before and during treatment with beclomethasone dipropionate 250, asthma control was improved in 69% of all patients. This was accompanied by a 53% reduction in the number of acute attacks requiring supplementary courses of oral corticosteroid and a 70% reduction in admissions to hospital. Prior to beclomethasone dipropionate 250, 21% of the steroid-dependent patients were maintained on alternate day prednisone whereas after the introduction of beclomethasone dipropionate 250, 44% of those 45 still requiring continuous prednisone were maintained on an alternate-day regimen.

Administration, Inhalation↗
PubMed1987

Colour vision abnormalities in multiple sclerosis.

A battery of colour vision tests was employed to evaluate visual function in patients with multiple sclerosis (M.S.). Colour deficits were found in 45% of patients tested with the Ishihara plates and 42.5% of patients tested with the FM 100-Hue test. 65% of M.S. patients failed at least one of the tests. The colour vision deficits were not restricted to patients with optic neuritis or with visual evoked potential (VEP) abnormalities and there was no significant correlation between an abnormal VEP latency and a colour vision deficit. Colour vision testing may be a useful option to consider in the investigation of M.S. patients, even if there is no other evidence of visual system involvement.

Adult↗
PubMed1986

Tuberculosis at Green Lane Hospital 1980-1982.

An audit of tuberculosis management at Green Lane Hospital was undertaken by review of the case records of 235 cases of adult tuberculosis. There were 135 men and 100 women (mean age 47 years). Important findings include the large proportion of nonEuropeans (66%) and the frequency of drug resistance. Drug resistance was present in 29% of isolates from nonEuropean immigrants who had resided in New Zealand for a year or less. The adequacy of current medical screening of Pacific Island and South-east Asian visitors and immigrants is discussed in the context of these findings. Treatment regimens used were in accordance with accepted recommendations, although the duration (14 months in uncomplicated disease) was longer than is now thought necessary. Of the 205 patients who completed treatment under our care 186 (91%) were cured, 14 (6.8%) died, 3 (1.5%) relapsed and two defaulted. The median in hospital stay was 32 days and together with the somewhat high relapse rate (1.5%) reflects the absence of facilities for closely supervised outpatient tuberculosis treatment in Auckland.

Adolescent↗
PubMed1979

Giant condyloma (Buschke--Loewenstein tumor) of the anorectum.

A case of giant condyloma of Buschke and Loewenstein is presented. The clinical course and pathology of these tumors are reviewed. This case illustrates the delay in establishing the diagnosis in spite of numerous biopsies. It is emphasized that the only effective treatment is wide local excision.

Adult↗
PubMed1979

Combined cholinergic antagonist and beta 2-adrenoceptor agonist bronchodilator therapy by inhalation.

The bronchodilator effects of 40 microgram ipratropium bromide (I) and 400 microgram fenoterol (F) by pressurised aerosol and both drugs in combination were compared with placebo (P) in a double-blind study in eight patients with chronic, partially reversible airways obstruction. The four treatments were (1) IP, (2) PF, (3) IF and (4) PP, with the second aerosol administered two hours after the first. Both drugs produced significant bronchodilatation for five hours, the response being greater and more rapid in onset with fenoterol. Both drugs in combination (IF) produced significant additive bronchodilatation from three to six hours after fenoterol. This additive effect may have been due to the improved lung function caused by ipratropium bromide and does not imply a synergistic effect. There were no side-effects reported. The results suggest that both ipratropium bromide and fenoterol are effective bronchodilating agents in patients with chronic asthma.

Adult↗
PubMed1979

Tracheobronchopathia osteochondroplastica.

The clinical, pathological and physiological features of two patients suffering from tracheobronchopathia osteochondroplastica (TO) are described. Unequivocal evidence of extrapulmonary airways obstruction was not able to be obtained by lung function testing, despite extensive central airway involvement in both patients. TO is a rare condition of which there is only one other clinical report from this country. As the bronchoscopic appearance may closely resemble that of endobronchial neoplasms, TO should be remembered in the differential diagnosis of patients with haemoptysis.

Aged↗