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Biomedical subjects

L Bradshaw

Publications and source records attributed to L Bradshaw.

13 recordsLinked to original sources
PubMed2001

Work-related respiratory symptoms in New Zealand farmers.

BACKGROUND: The first national survey of the respiratory health of New Zealand farmers looked at the prevalence of respiratory symptoms by farm type and work exposure. METHODS: An 8-page questionnaire was mailed to 2,203 farmers randomly selected from all over New Zealand. RESULTS: Response rate was 77.6% of 2,203, or 1,706 participants. Breathing problems at work were reported by 17.6% of farmers. Working with oats was strongly associated with work-related breathing problems (OR = 3.3, 2.1-5.2). Dyspnea was more common in female farmers, whereas chronic bronchitis was higher in males. Orchardists (OR = 2.3, 1.3-4.0), those growing oat crops (OR = 3.0, 1.7-5.4) and using the grain mill (OR = 2.8, 1.3-6.3) reported the highest symptom rates of ODTS/FL. Having hay fever or eczema, and smoking were risk factors for all respiratory symptoms. CONCLUSIONS: Working in the areas of pigs, poultry, horses, grains, and hay are associated with respiratory symptoms in New Zealand farmers.

Adolescent↗
PubMed2001

Cumulative and single-dose design to assess the bronchodilator effects of beta2-agonists in individuals with asthma.

With the development of different chlorofluorocarbon (CFC)-free metered dose aerosol and dry powder devices, it is necessary to study and validate the methods used for assessing and comparing their efficacy. This study evaluated the cumulative dose design by determining the bronchodilator response to salbutamol given according to either a high or a low cumulative dose regimen. Adults with asthma (n = 24) were studied in a placebo-controlled, randomized, double-blind, cross-over design. On separate days, cumulative doses of salbutamol (50+50+100+200 or 100+100+ 200+400 or 400+0+0+0 or 0+0+0+0 microg) were given via Turbuhaler with 30 min between doses. The two cumulative dose regimens produced almost identical bronchodilator responses at each time point. The relative dose-potency between the 800- and 400- microg cumulative dose regimens was 0.7 with a 95% confidence interval of 0.5-1.0, excluding the true value of 2. The 400-microg cumulative dose regimen resulted in a higher FEV1 at 115 min than the 400-microg single-dose regimen. There was no difference in the bronchodilator response to the single dose of 50, 100, or 400 microg of salbutamol after either 5 or 25 min. Thus, care should be exercised when using either a cumulative or single-dose design for comparing different beta2-agonists, or different inhalation devices, with respect to their relative dose-potency. In addition, this study provides further evidence that for short-acting beta2-agonists such as salbutamol, lower doses than those normally recommended may be used, and that repeated self-administration of low doses over a period of 60 min may give a better bronchodilator response than a single administration of a high dose.

Administration, Inhalation↗
PubMed2000

Changes in work practice after a respiratory health survey among welders in New Zealand.

AIMS: To assess changes in work practice among eight New Zealand engineering sites, following a study of occupational respiratory symptoms in welders two years previously. METHODS: In 1996, we found that an acute decrease in lung function was more common in welders working without local exhaust ventilation. Findings were reported back to management, study participants and the media. Two years later we re-visited the eight welding sites. RESULTS: Of the eight engineering sites, two had local exhaust ventilation present in both Study 1 and Study 2, one site had installed local exhaust ventilation in part of the site since Study 1 and one site had moved to larger premises. The remaining four sites had no exhaust ventilation or change to the workplace between studies. Five welders (12.8%) used respiratory protection in both Study 1 and Study 2, seven welders (18%) used respiratory protection in Study 1 but not Study 2, four welders (10.3%) did not have respiratory protection in Study 1 but did in Study 2 and nine welders (23.1%) did not use respiratory protection at all in Study 1 or Study 2. CONCLUSION: Further effort is required to ensure that such studies lead to significant improvements in the work environment.

Air Pollutants, Occupational↗
PubMed2000

Occupational respiratory symptoms in New Zealand hairdressers.

BACKGROUND: A study of occupational respiratory symptoms in hairdressers was carried out in 26 salons in New Zealand. METHODS: A questionnaire was administered to 100 hairdressers and 106 office and shop workers, recording respiratory symptoms, demographic data, and smoking habits. Pulmonary function was measured before each shift. RESULTS: Hairdressers had a higher prevalence of asthma symptoms, diagnosed asthma, and asthma attacks in the previous 12 months, but these differences reduced markedly when adjusted for age, gender and smoking. Hairdressers had a significantly lower pulmonary function, even after adjustment for smoking, but this difference was entirely due to differences between hairdressers and office workers and there were no such differences between hairdressers and shop workers. CONCLUSIONS: The excess symptom prevalence in hairdressers was largely due to the high smoking rates. Mean pulmonary function was lower in hairdressers but this finding requires further study.

Adolescent↗
PubMed1999

Asthma and allergy in New Zealand farmers.

AIMS: To examine the prevalence of symptoms of asthma and allergy in different farming groups in New Zealand. METHODS: A postal questionnaire was sent to a random sample of 2,500 farmers throughout New Zealand. RESULTS: The response rate was 77% (1,706 of 2,203 eligibles). The 12-month period prevalence of current asthma was 11.8% overall, compared with 15% in the general population. Asthma prevalence was higher for horse breeders/groomers (16.5%), pig farmers (18.2%), poultry farmers (17.4%), and those working with oats (17.4%). Asthma was also significantly elevated among those working with cleaning powders (14.7%). Women were more likely to report current asthma than were men (OR 1.8, 95% CI 1.3-2.5). Hay fever was significantly higher in deer and crop farmers, and farmers working with horses and goats; eczema was higher for goat and deer farmers. CONCLUSIONS: The lower overall prevalence of asthma in farmers may be due to the healthy worker effect. Among farmers, the types of farming associated with an elevated prevalence of asthma and allergy in New Zealand are deer and goat farming, working with horses, poultry, pigs, and crop farming. Females reported more current asthma than males.

Adolescent↗
PubMed1999

Two year follow up of pulmonary function values among welders in New Zealand.

OBJECTIVES: To examine whether welding is a risk factor for an accelerated decline in pulmonary function. METHODS: 2 Year follow up of pulmonary function and respiratory symptoms among 54 welders and 38 non-welders in eight New Zealand welding sites. RESULTS: There were no significant differences in age, height, smoking habits, ethnicity, or total time in industrial work between welders and non-welders. No overall differences were noted in the changes of pulmonary function variables between the two study groups. However, when the comparison was restricted to smokers, welders had a significantly greater (p = 0.02) annual decline (88.8 ml) in FEV1 than non-welders, who had a slight non-significant annual increase (34.2 ml). Also, welders without respiratory protection or local exhaust ventilation while welding had a greater annual decline both in forced vital capacity (FVC) and forced expiratory volume in one second (FEV1) than welders with protection (p = 0.001 and 0.04, respectively). Among welders a significant association was found between the acute across shift change and the annual decline in FEV1. Chronic bronchitis was more common among welders (24%) than non-welders (5%). Only one welder (2%) but eight non-welders (21%) reported having asthma. CONCLUSIONS: Welders who smoked and welders working without local exhaust ventilation or respiratory protection have an increased risk of accelerated decline in FEV1.

Adult↗
PubMed1997

Respiratory questionnaire responses: how they change with time.

AIM: Responses to respiratory questionnaires are often used to identify individuals with asthma symptoms and may also be used to identify asymptomatic individuals. This study investigates the repeat responses over four years to such a questionnaire in a population of adult New Zealanders. METHODS: Seven hundred and twenty three asthmatics were sent two almost identical questionnaires in three areas of New Zealand, separated by approximately four years. All of them had answered yes to at least one of the three questions under study in the first survey. RESULTS: Following the second asthma questionnaire only 487 (67.4%) answered yes to at least one of the survey questions. Similarly, 51.1% of those who had reported having nocturnal shortness of breath in the first survey did so in the second survey, 69.9% of those who reported having had an asthma attack in the first survey did so in the second survey, and finally 74.8% of those who reported using asthma medication in the first survey did so in the second survey. CONCLUSION: Even in a previously identified symptomatic asthmatic group, a large proportion did not report respiratory symptoms and asthma medication use four years later. This implies that the true prevalence pool of susceptibles is likely to be far greater than is identified in surveys of the 12-month period prevalence of asthma symptoms. This has implications not only for the design of epidemiological studies (e.g., it poses problems for the selection of a control group of non-asthmatics in prevalence case-control studies), but also for the planning of health services and educational programmes for people with asthma.

Adult↗
PubMed1997

Under the volcano: fire, ash and asthma?

AIMS: To investigate the prevalence of respiratory symptoms in known asthmatics, following exposure to airborne volcanic ash particles caused by the eruptions of Mount Ruapehu, New Zealand, commencing September 1995. METHOD: A one page postal questionnaire was sent to 1392 previously identified asthmatics 2 months after the first major eruption. RESULTS: Two hundred and thirty seven subjects had moved from the area, died or gone overseas since the original contact 4 years previously; therefore the target population was 1155 subjects of whom 361 lived in the exposed area and 794 in the nonexposed areas. The response rates were 246 (68.1%) in the exposed group and 477 (60.1%) in the nonexposed group making a total of 723 individuals. The prevalence of nocturnal shortness of breath in the last two months was 29.3% in the exposed group and 24.7% in the nonexposed (OR = 1.26, 95% CI; 0.83-1.78). Similarly 30.9% of the exposed group had an asthma attack in the last 2 months compared to 31.9% of the nonexposed group (OR = 0.96, 95% CI; 0.69-1.33). Finally, 48.4% of the exposed group used asthma medication in the 2 months following the eruption in comparison to 53% of the nonexposed group (OR = 0.83, 95%, CI; 0.61-1.12). CONCLUSIONS: The study showed no association between living in an area exposed to volcanic ash particles and either asthma symptoms or the use of asthma medication. There was a small but nonsignificant increase in nocturnal shortness of breath in the exposed group.

Acute Disease↗
PubMed1992

Cisplatin-DNA damage and repair in peripheral blood leukocytes in vivo and in vitro.

We have extended our studies on the relationship between cisplatin/carboplatin-induced DNA damage in readily accessible tissue(s) and clinical response to therapy. Such an approach may assist in the study of cancer drug resistance and in establishing parameters for assessing human populations for sensitivity to DNA damaging agents in the environment. Platinum-DNA adduct levels were measured by atomic absorbance spectrometry. DNA repair capacity was assessed in human T-lymphocytes by the ability to repair cisplatin lesions in cellular DNA or in transfected plasmid DNA. In a "blinded" study of 21 patients receiving combination cisplatin/carboplatin drug therapy, there was a direct relationship between DNA damage in leukocytes and disease response (summary two-sided p = 0.00011). The cohort of patients had 15 different tumor types, suggesting that blood tissue and tumor tissue of an individual may process platinum-DNA damage similarly regardless of the tissue of origin of the tumor. In leukocytes in vivo, persistence and accumulation were prominent features of the cisplatin-DNA adduct profile. Functional DNA repair capacity has been studied in eight human leukocyte cell lines in vitro (three, T-cells; three, B-cells; one, monocytic; one, promyelocytic), using a host cell reactivation assay with cisplatin-damaged pRSVcat. In the three T cell lines studied, host cell reactivation efficiency was directly related to the cells' abilities to repair cisplatin-damaged cellular DNA (correlation coefficient = 0.993).(ABSTRACT TRUNCATED AT 250 WORDS)

Carboplatin↗