Search PubMed⌕ Search

Biomedical subjects

S B Pearson

Publications and source records attributed to S B Pearson.

At least 19 recordsLinked to original sources

Genetic alterations in bronchial mucosa and plasma DNA from individuals at high risk of lung cancer.

Evidence suggests that the majority of lung cancer patients have tumour-derived genetic alterations in circulating plasma DNA, and that this may be developed as a diagnostic tool. To this end, we have studied 60 individuals attending bronchoscopy clinic, with symptoms suspicious of lung cancer, for genetic alterations in bronchial mucosa biopsy (n = 47) and plasma (n = 40) DNA. Thirteen of 47 individuals from whom biopsies were taken displayed allelic loss of heterozygosity (LOH) in biopsy DNA for at least 1 of 4 markers. All 13 of these individuals had neoplastic tumour cells in their biopsies and were subsequently diagnosed with cancer. Thirteen of 40 individuals from whom plasma was taken displayed a plasma DNA LOH, and 12 of these 13 individuals were subsequently diagnosed with cancer. LOH in plasma was generally representative of LOH in the corresponding biopsy. In terms of sensitivity, using just 4 markers, biopsy LOH and plasma LOH were found in 13 of 44 (30%) and 12 of 29 (41%), respectively, of those patients subsequently diagnosed with cancer. Two patients were positive for LOH in plasma samples that pre-dated a diagnosis of cancer by several months. These data suggest that assay of genetic alterations in circulating plasma DNA may be developed as a useful addition to conventional techniques for the diagnosis of lung cancer.

Adult↗

Breast metastasis from non-small cell lung cancer.

Breast is an unusual site for metastatic disease, particularly for non-small cell lung cancer. We report an unusual case of metastatic breast lesions from a primary anaplastic lung tumor and discuss the common and uncommon sites of metastasis from lung carcinomas.

Breast Neoplasms↗

Comparison of nebulised salbutamol and ipratropium bromide with salbutamol alone in the treatment of chronic obstructive pulmonary disease.

BACKGROUND: Patients admitted with acute exacerbation of chronic obstructive pulmonary disease (COPD) are often prescribed ipratropium bromide in combination with a beta 2 agonist such as salbutamol. Studies have not shown any benefit in adding ipratropium bromide to salbutamol in acute exacerbations of COPD, but these studies have only assessed patients for 60-90 minutes and short term studies may not predict long term clinical response. Combination therapy with the two drugs was compared with salbutamol alone in the treatment of acute exacerbations of COPD during a hospital admission. METHODS: Seventy patients admitted to hospital with an acute exacerbation of COPD were randomly allocated to receive either nebulised salbutamol 5 mg and ipratropium bromide 500 micrograms, or nebulised salbutamol 5 mg alone (all four times a day) on admission. All other treatment was prescribed at the discretion of the attending physician. Length of stay in hospital and spirometric values on days 1, 3, 7, 14, and discharge were assessed. Patients completed a subjective symptom score each day. RESULTS: There was no difference between the two groups in the mean (SD) length of stay (salbutamol 10.5 (4.7) days, salbutamol + ipratropium bromide 11.8 (4.4) days; 95% CI -1.02 to 3.62). There was no difference in spirometric values on days 1, 3, 7, 14, or discharge between the two groups. The subjective improvement was similar with both treatments. CONCLUSIONS: The routine addition of nebulised ipratropium bromide to salbutamol appears to be of no benefit in the treatment of acute exacerbations of COPD.

Administration, Inhalation↗

Childhood tuberculosis in Leeds, 1982-90: social and ethnic factors and the role of the contact clinic in diagnosis.

A retrospective analysis of childhood tuberculosis in Leeds over a nine year period (1982-90) was performed which showed that the contact clinic is important for the early detection and treatment of disease in children. Two thirds of the cases of tuberculosis in children under 15 years were diagnosed and treated at the clinic. The incidence of tuberculosis was greater in Asian than in white children and, independent of race, was greater in the most deprived area of the city.

Adolescent↗

Bambuterol: effective in nocturnal asthma.

Bambuterol was compared with placebo in 28 patients with nocturnal asthma in a randomized, double-blind cross-over study. All patients were symptomatic despite taking inhaled beta 2-agonists, inhaled corticosteroids (in 26 patients the median daily dose was 1500 micrograms) and oral corticosteroids (in eight patients the median daily dose was 10 mg). Patients demonstrated > or = 20% overnight fall in peak expiratory flow (PEF) for at least half of the 14-day run-in period. They then entered two treatment periods lasting 14 days when bambuterol 20 mg nocte and placebo were given in random order. Compared to placebo, bambuterol produced a 16% improvement in mean PEF on waking (271 l min-1 vs. 239 l min-1 P = 0.0002) and a 10% improvement in evening PEF measured 24 h after drug intake (318 l min-1 vs. 296 l min-1 P = 0.01). Bambuterol significantly reduced frequency of nocturnal awakening from 1.1 to 0.7 per night (P = 0.01) and nocturnal beta 2-agonist use from 2.7 to 2.1 puffs (P = 0.0004). Other nocturnal symptoms: cough, wheeze and dyspnoea were also significantly reduced during bambuterol treatment and patients quality of sleep was improved. The results indicate bambuterol (20 mg nocte) provides effective nocturnal bronchodilation with sustained effect for 24 h and may have a useful therapeutic role in the control of symptomatic nocturnal asthma.

Adult↗

The association of age with the presentation and outcome of tuberculosis: a five-year survey.

Of the 411 patients notified with tuberculosis in Leeds during 1986 through 1991, case notes were available on 406 (99%) and the diagnosis of mycobacterial disease was accepted in 397 (98%). Twenty-two patients had infection with atypical mycobacteria and were excluded from analysis, as were children under 16 years. Comparison between the age groups was further restricted to white patients because of a skew distribution of Asian patients towards the younger age range. Ninety-six elderly patients (aged 65 years and older) were compared with 127 younger patients. The distribution of pulmonary and extrathoracic disease was similar as was the incidence of positive bacteriology. Elderly people had more frequent lower-zone and more frequent miliary shadowing, otherwise radiographic features were similar. Elderly people were nearly three times more likely to have reactions to antituberculous drugs, six times more likely to die from tuberculosis and over twenty times more likely than younger patients to have the diagnosis made at autopsy rather than during life.

Adolescent↗

Heaf status 12 years after infant BCG immunization.

Uncertainty exists over the long-term influence of Heaf status and immunity of infant BCG immunization. BCG is offered to all Leeds Asian infants with uptake estimated at 86%. We have examined the effect of this immunization policy on the Heaf status of all 12- to 13-year-old children tested in the city in 1988. 6363 children (431 Asians) were eligible for Heaf testing of whom 5379 (366 Asians) were tested. 90 (25%) Asians and 4596 (92%) non-Asians had a Heaf grade 0-1 with no definite previous BCG and were, using current UK Department of Health recommendations, eligible for BCG immunization. With an annual incidence of tuberculosis in Asian children in Leeds of only 6 per 100,000 it is probable that most of the 75% of Asian children who did not require immunization had persisting immunity from their infant BCG rather than as a result of primary infection. We conclude that infant BCG immunization is effective at providing appropriate immunity, avoiding repeat BCG, in most children at age 12 years.

Adolescent↗

Response to nebulized ipratropium bromide and terbutaline in acute severe asthma.

Outpatient studies on asthmatics have shown that inhaled anti-cholinergic agents decrease in efficacy as FEV1 falls. To determine whether there are changes in response to inhaled anti-cholinergics during acute bronchoconstriction we have examined the effects of nebulized ipratropium and terbutaline in nine hospitalized patients recovering from acute severe asthma. At 6 a.m. each day throughout the admission, baseline PEFR was recorded. Ipratropium bromide, 1 mg, was nebulized and PEFR measured again 1 h later. Following this, terbutaline, 5 mg, was nebulized with further measurement of PEFR 15 min after nebulization. Results were analysed by paired t-tests. Mean baseline PEFR rose from 157 l m-1 on patients worst day to 300 l m-1 on their best day (P less than 0.01). Ipratropium improved mean PEFR by 55 l m-1 and 42 l m-1 on patients worst and best days respectively (P less than 0.01). Subsequent terbutaline improved mean PEFR on patients worst day by 23 l m-1 (P less than 0.01) but only by a non-significant 4 l m-1 on their best day (P = 0.09). Hence, ipratropium produced 96% of total bronchodilatation when baseline was highest, but achieved only 71% of total response when baseline was lowest, a highly significant change in response (P less than 0.01). We conclude that in acute severe asthma as baseline PEFR rises response to inhaled ipratropium improves, compared with total response to combined ipratropium followed by terbutaline.

Acute Disease↗

Outbreak of tuberculosis in a poor urban community.

A woman from a poor urban community presented recently with pulmonary tuberculosis. Screening of contacts revealed 10 cases of tuberculosis, eight of whom were children. A further 10 children had grade 2-3 positive Heaf tests and were given chemoprophylaxis. Tuberculosis remains a potential problem, particularly in young unimmunized children in deprived areas.

Adolescent↗

The parasympathetic nervous system and the diurnal variation of lung mechanics in asthma.

In a placebo-controlled double-blind experiment the effects of cholinergic blockade with 30 micrograms kg-1 atropine administered by intravenous injection have been studied in nocturnal asthma. Cholinergic blockade at night reversed the changes in indices of airflow in small airways and of gas trapping to the values seen after administration of atropine during the daytime. However, the improvement in indices of airflow in large airways was not complete, reaching only the daytime placebo levels. No changes were seen in any aspect of breathing pattern. The results are discussed in relation to the literature.

Adult↗

Time of development of tuberculosis in contacts.

The British Thoracic Association has recommended that close contacts of smear-positive cases of tuberculosis be followed up for at least 2 yrs (Tubercle 1978; 59: 245-259) but Selby et al. have recently suggested that a reduction in duration of follow up may be appropriate (Respir Med 1989; 83: 353-355). We have reviewed the results of contact procedures in Leeds to determine whether our experience supports reduction in the duration of follow up of contacts of patients with tuberculosis. In the 5-yr period 1983-87 there were 555 cases of tuberculosis (135 in Asians) of whom 42 (7.6%) were identified by contact procedures. In addition, contact procedures identified 35 children who were given chemoprophylaxis for positive Heaf tests (grade 2 or more). Of the 42 contacts with tuberculosis, 30 (71%) were diagnosed at the first visit, eight (19%) were diagnosed 6 months later and four (10%) were diagnosed 16-24 months after their initial clinic attendance. Five of the 42 contacts with TB were Asian, two of whom were diagnosed late. Seven out of ten non-Asian contacts who were diagnosed late had initial Heaf reactions of grade 1 or 2. All cases diagnosed late were contacts of a sputum-positive source. Poverty, as defined by residence in the Leeds Urban Priority Area, was associated with an increased risk of 3.3-fold for tuberculosis and a sixfold risk for chemoprophylaxis diagnosed by contact procedures.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗

Effects of H1-receptor blockade with terfenadine in nocturnal asthma.

1. In a single-blind placebo controlled study we have measured peak flow (PEFR) at 04.00 h and 16.00 h in eight asthmatics 6 h after placebo or terfenadine 120 mg, to determine if diurnal variation in histamine mediated effects contribute to nocturnal bronchoconstriction in asthma. 2. On placebo there was a significant diurnal variation in mean PEFR of 41 l min-1 (P less than 0.05). Terfenadine improved 04.00 h baseline mean PEFR from 242 to 278 l min-1 (P less than 0.05) but a 38 l min-1 diurnal variation in mean PEFR persisted (P less than 0.05). 3. We conclude that H1-receptor blockade with terfenadine may produce modest nocturnal bronchodilatation but does not influence the diurnal variation in PEFR in asthma suggesting that H1-receptor mediated effects are not important in the pathogenesis of nocturnal asthma.

Adult↗

Regular nebulised terbutaline in chronic obstructive airways disease: dose-response studies fail to detect tolerance.

1. To determine the effects of high dose terbutaline on the possible development of tolerance we have examined the influence on dose-response of regular nebulised terbutaline. 2. We studied 10 subjects with severe chronic obstructive airways disease (COAD), mean age 63 years mean (s.e. mean) PEFR 142 l min-1 (19), FEV1 0.77 1 (0.12) and FVC 1.93 (0.19). Cumulative dose-response curves were measured (PEFR, FEV1 and FVC) to six incremental doses of terbutaline (0.5-8 mg) before and 1, 4, 8 and 12 weeks after starting nebulised terbutaline 5 mg four times a day. 3. Maximal bronchodilatation (Emax) was calculated by polynomial regression. Responses were examined by analysis of variance. 4. Mean baseline PEFR increased by 32 l min-1 (P less than 0.05), FEV1 by 0.16 1 (NS) and FVC by 0.54 l (P less than 0.05) after 12 weeks. Initial mean Emax PEFR was maintained throughout the study. The percentage of mean Emax PEFR achieved by each cumulative dose of terbutaline either increased (0.5 mg, 1 mg and 2 mg, P less than 0.01) or was maintained (4 mg, 6 mg and 8 mg) throughout the study. 5. We conclude that in severe COAD regular nebulised terbutaline 5 mg four times a day produces a sustained improvement in baseline lung function without changes in dose-response which would suggest tolerance.

Adult↗