Search PubMed⌕ Search

Biomedical subjects

R M Rudd

Publications and source records attributed to R M Rudd.

At least 91 records · Page 5Linked to original sources
PubMed1985

A comparison of oral cefuroxime axetil and oral amoxycillin in lower respiratory tract infections.

We assessed oral cefuroxime axetil in an open study of 30 patients with lower respiratory tract infection and then compared oral cefuroxime with oral amoxycillin in a randomized double blind study in a further 40 patients. Satisfactory clinical responses were obtained in 73% of patients receiving cefuroxime axetil 500 mg tid in the open study, and in the comparative study in 71% of patients receiving cefuroxime axetil 500 mg bd, in 60% of patients receiving cefuroxime axetil 500 mg tid and in 63% of patients receiving amoxycillin 500 mg tid. There were no significant differences in response rates between the three regimens in the comparative study. There were no important adverse effects in any of the patients. Oral cefuroxime axetil is safe and effective in the therapy of lower respiratory tract infections.

Administration, Oral↗
PubMed1985

Regional distribution of pulmonary epithelial permeability in normal subjects and patients with asbestosis.

The overall and regional clearance of an inhaled isotope labelled solute from the lungs was examined on the basis of a 15 minute period of data collection, for which a technique was developed that does not require intravenous injection to correct for blood-tissue background activity. The technique was applied to 52 normal subjects (31 non-smokers and 21 smokers) and to 37 patients with asbestosis (21 non-smokers and 16 smokers). In normal smokers solute clearance was faster in the upper and middle zones, with a mean ratio of T1/2 LB (half time solute clearance from lungs to blood) in the upper two thirds to the lower one third of the lungs of 0.66 (0.28-1.33), compared with 1.24 (0.43-2.77) in normal non-smokers (p less than 0.002). In patients with asbestosis solute clearance was accelerated throughout the lungs even though radiographic abnormalities were limited to lower or lower to middle zones. Regional distribution of clearance was not affected by posture in normal subjects. Overall solute clearance was significantly faster in normal current smokers and in patients with asbestosis than in normal non-smokers (p less than 0.001 respectively). Among patients with asbestosis, smokers had faster overall clearance than non-smokers (p less than 0.01). Among normal non-smokers T1/2 LB was not significantly different between those who had never smoked and ex-smokers. Regional abnormalities in pulmonary epithelial permeability may offer insight into the pathogenesis of interstitial lung diseases and smoking related disorders.

Adult↗
PubMed1985

Asbestosis: assessment by bronchoalveolar lavage and measurement of pulmonary epithelial permeability.

Thirty two patients with asbestosis were assessed by means of bronchoalveolar lavage (27 patients) and the half time clearance from lungs to blood (T1/2LB) of an inhaled aerosol of diethylenetriamine pentacetate (DTPA) labelled with technetium 99m (32 patients). T1/2LB was also measured in 20 non-smoking normal individuals and 17 smokers without a history of exposure to asbestos. Thirteen patients (46%) showed an increase in the percentage of neutrophils with or without an increase in the percentage of eosinophils and eight (29%) showed an increased percentage of lymphocytes. The number of neutrophils plus eosinophils expressed as a percentage of the total count was positively correlated with the length of the history of disease (r = 0.53, p less than 0.025) and greater percentages were associated with more severe impairment of lung function. Smokers had lower percentages of lymphocytes than non-smokers (p less than 0.002) and showed increased proportions of neutrophils and eosinophils more often than non-smokers (p less than 0.05). In 18 non-smokers with asbestosis the mean T1/2LB was 33.8 (range 10.0-62.0) minutes, significantly less than 57.2 (30.5-109) minutes in 20 non-smoking normal subjects (p less than 0.002). In non-smokers shorter T1/2LB correlated with a longer time since first exposure to asbestos (r = -0.65, p less than 0.005), longer duration of exposure (r = -0.70, p less than 0.001), and a shorter time since last exposure (r = 0.59, p less than 0.01). Shorter T1/2LB was also associated with increased inflammatory activity as shown by higher bronchoalveolar lavage cell counts (r = -0.53, p less than 0.025) and higher combined percentages of neutrophils, eosinophils, and lymphocytes (r = -0.47, p less than 0.05). The techniques of bronchoalveolar lavage and measurement of inhaled solute clearance may be useful in assessing inflammatory activity in asbestosis.

Adult↗
PubMed1985

Lymphocyte subpopulations in bronchoalveolar lavage fluid in asbestos workers.

We examined peripheral blood and bronchoalveolar lavage (BAL) fluid lymphocyte subpopulations in 29 asbestos workers, 10 with and 19 without clinical or radiologic evidence of asbestosis. Peripheral blood lymphocyte subpopulations were also measured in 13 control subjects. The mean OKT4:OKT8 (T-helper/inducer:T-suppressor/cytotoxic lymphocyte) ratio in BAL fluid in the 29 asbestos workers was 0.96 (range, not detected to 3.33), significantly less than 1.76 (1.33 to 2.67) in peripheral blood (p less than 0.001). There were no significant differences in OKT4:OKT8 ratios in peripheral blood between the 10 patients with asbestosis, the 19 asbestos workers without asbestosis, and the 13 normal control subjects or in the OKT4:OKT8 ratios in BAL fluid between patients with asbestosis and asbestos workers without asbestosis. In the group as a whole, 83% of those who had suffered more than 5 yr of exposure to asbestos showed OKT4:OKT8 ratios less than 1.2, whereas in those who had suffered fewer than 5 yr of exposure, 80% showed ratios greater than 1.2 (p less than 0.02). No other relationships between OKT4:OKT8 ratios and clinical, radiographic, or physiologic variables were observed.

Adult↗
PubMed1985

Use of the flexible film isolator as a single circuit hypoxic chamber for small animals.

PVC isolators are now widely used for housing animals and provide a readily available pretested air-tight chamber (Pendry, 1984; Trexler, 1984). We have adapted a flexible film isolator for use as a hypoxic chamber for small animals. The environment within the chamber can be easily and continuously monitored with indwelling probes, obviating the need for a separate circuit for gas analysis. This design has been used for long-term studies of chronic hypoxia.

Animals↗
PubMed1985

Asbestosis. Bronchoalveolar lavage fluid proteins and their relationship to pulmonary epithelial permeability.

We measured levels of albumin and immunoglobulins in serum and bronchoalveolar lavage (BAL) fluid in 28 men with asbestosis and 11 control subjects. The half-time clearance of inhaled diethylene triamine pentacetate labelled with technetium-99m (99mTc-DTPA) from the lungs (t1/2LB) was measured in 26 patients with asbestosis and in 31 normal nonsmoking controls. In those individuals in whom immunoglobulins were detected in BAL fluid, the mean IgG:albumin ratio in BAL fluid was 0.30 (range, 0.11 to 0.97), significantly less than the ratio of 0.43 (0.28 to 0.66) in control subjects (p less than 0.05). There was no significant difference in IgA:albumin ratios between patients and control subjects. The mean BAL:serum albumin ratio in patients with asbestosis was 2.3 X 10(-3) (range, 0.2 to 9.5 X 10(-3), significantly greater than the ratio of 1.2 X 10(-3) (0.5 to 2.0 X 10(-3] in control subjects (p less than 0.02). The t1/2LB was significantly shorter in both smokers and nonsmokers with asbestosis, compared with 31 normal nonsmoking controls, but there were no relationships between t1/2LB and BAL:serum albumin ratio or any other BAL protein levels in either smokers or nonsmokers with asbestosis.

Adult↗
PubMed1985

Bronchoalveolar lavage and clearance of 99m-Tc-DTPA in asbestos workers without evidence of asbestosis.

We performed BAL and measured the clearance of 99m-Tc-DTPA in 20 non-smoking subjects (mean age 50, range 36-68 years) occupationally exposed to asbestos (mean duration 14, range 3-30 years). All had normal lung function and none had clinical or radiological evidence of asbestosis. The mean BAL results were: total cells per ml 737 X 10(3) (360-1210), percentage macrophages 79 (49-96), percentage lymphocytes 13 (1-42), percentage neutrophils 8 (1-40), percentage eosinophils 0 (0-3), asbestos bodies per ml 83 (0-550). Eight subjects showed increased percentage of lymphocytes and four others showed increased percentages of neutrophils when compared with normal ranges in our laboratory. Higher percentages of neutrophils correlated with longer duration of exposure to asbestos (r = 0.54, P less than 0.025), and shorter time since last exposure to asbestos (r = -0.54, P less than 0.025). Four subjects showed faster clearance of 99m-Tc-DTPA than was observed in 31 normal non-smoking control subjects. There was a tendency for faster solute clearance to be associated with greater numbers of BAL macrophages (r = -0.39, P less than 0.10) but there were no significant relationships between solute clearance and other BAL variables. BAL profiles in asbestos workers may be abnormal in the absence of clinical or radiological evidence of asbestosis.

Adult↗
PubMed1984

Effects of oral and inhaled salbutamol and oral pirbuterol on right and left ventricular function in chronic bronchitis.

In many patients with chronic bronchitis and emphysema right and left ventricular ejection fractions (RVEF and LVEF) are reduced. A study was conducted using multiple gated equilibrium radionuclide ventriculography to compare the effects of oral salbutamol 4 mg and pirbuterol 15 mg on cardiac function in 12 patients with chronic bronchitis (forced expiratory volume in one second 0.86 (SEM 0.12) 1; arterial oxygen pressure 8.2 (SEM 0.5) kPa (61.7 (SEM 3.8) mm Hg)). Different doses of nebulised salbutamol (500 microgram and 5 mg) were also compared in nine of the patients. Both oral salbutamol and oral pirbuterol produced significant increases in RVEF and LVEF at 60 and 90 minutes after drug ingestion (p less than 0.01 in each case). There were no significant differences between salbutamol and pirbuterol in their effects on RVEF and LVEF. Inhaled salbutamol at doses commonly prescribed had no significant effect on RVEF and LVEF after 20 and 60 minutes. Salbutamol and pirbuterol given by mouth have similar actions on RVEF and LVEF. Further studies are necessary to assess the effects of long term B2 agonists in this group of patients.

Administration, Intranasal↗
PubMed1984

The effects of theophylline and salbutamol on right and left ventricular function in chronic bronchitis and emphysema.

We have compared the effects of oral theophylline and salbutamol on right and left ventricular function in twelve patients with chronic bronchitis and emphysema. Right and left ventricular ejection fraction (RVEF and LVEF) were measured using multiple gated radionuclide ventriculography. Theophylline 600 mg and salbutamol 4 mg both produced increases in RVEF and LVEF. There were no significant changes in blood gases after either drug. The clinical significance of the effects of oral bronchodilators on cardiac function in patients with chronic bronchitis and emphysema has yet to be determined.

Adult↗
PubMed1984

Erythrapheresis compared with placebo apheresis in patients with polycythaemia secondary to hypoxic lung disease.

We have assessed the effects of erythrapheresis, a method of isovolaemic haemodilution, and placebo apheresis in 10 patients with polycythaemia secondary to chronic hypoxic lung disease (Mean PaO2 7.2kPa (54 mm Hg]. The mean packed cell volume decreased from 0.60 to 0.48, with significant decreases in blood viscosity at both high and low shear rates (p less than 0.001). The 6-min walking distance improved after erythrapheresis with no significant placebo effect of the procedure compared to control subjects (p less than 0.01). Erythrapheresis is a safe procedure for packed cell volume reduction. It is associated with clinical improvement and there is no demonstrable placebo effect on exercise tolerance.

Blood Viscosity↗
PubMed1984

Bronchoalveolar lavage in the diagnosis of diffuse pulmonary shadowing.

Bronchoalveolar lavage (BAL) was performed during fibreoptic bronchoscopy in 79 patients with undiagnosed diffuse radiographic pulmonary shadowing and in 20 control subjects undergoing investigation for respiratory symptoms not associated with diffuse radiographic shadowing. The highest percentages of cells other than macrophages found in BAL fluid from the controls were 11% for lymphocytes and a total of 10% for neutrophils and eosinophils. 72 (91%) of the patients with diffuse shadowing had higher percentages of one or more of these inflammatory cell types than were found in any of the controls. Patients with increased lymphocytes differed in their eventual diagnosis from those without increase lymphocytes but with increases in other inflammatory cells (P less than 0.001). The use of BAL cell profiles as an aid to diagnosis in certain situations is illustrated by calculation of predictive values using Bayes' theorem. BAL has diagnostic value in the investigation of diffuse pulmonary shadowing if the cell profile is considered in conjunction with other information.

Adolescent↗
PubMed1983

Erythrapheresis in patients with polycythaemia secondary to hypoxic lung disease.

Erythrapheresis was performed in 10 patients with polycythaemia secondary to hypoxic lung disease (mean PaO2, 6.8 kPa (51 mm Hg)). The mean packed cell volume decreased from 0.64 to 0.48 in men and from 0.56 to 0.42 in women, with significant decreases in blood viscosity at both high and low shear rates (p less than 0.001). Patients showed significant improvement in six-minute walking distances (p less than 0.001) and in tests of mental alertness (p less than 0.01) compared to control subjects. Visual analogue scales confirmed symptomatic improvement after erythrapheresis. Erythrapheresis significantly improved symptoms, mental function, and work performance in patients with polycythaemia secondary to hypoxic lung disease. The procedure was well tolerated by all patients and no complications occurred.

Aged↗
PubMed1983

Inhibition of exercise-induced asthma by an orally absorbed mast cell stabilizer (M & B 22,948).

M&B 22,948 (2-o-propoxyphenyl-8-azapurin-6-one) is an orally absorbed mast cell stabilizer which is 30 times as potent as disodium cromoglycate in laboratory and animal studies. In a double-blind placebo-controlled cross-over trial we studied the protection afforded by a single oral dose of 10 mg of M&B 22,948 against asthma induced by histamine and exercise, each in 12 patients. Compared with placebo the drug had no significant effect on the response to inhaled histamine but significantly inhibited the fall in FEV1 induced by exercise on treadmill (P less than 0.005). The exercise-induced fall in FEV1 was less following M&B 22,948 than placebo in all patients and the fall was inhibited by more than 50% in five (42%) of 12 patients. The degree of inhibition was significantly correlated with the plasma drug concentration (r = 0.65, P less than 0.025). M&B 22,948 merits evaluation in the treatment of asthma.

Adolescent↗
PubMed1982

Comparison of Mantoux, tine, and 'Imotest' tuberculin tests.

In a study designed to compare the Mantoux with the tine and 'Imotest' multiple-puncture tuberculin tests 200 subjects underwent a Mantoux test (10 IU PPD-Weybridge) and, simultaneously, either a tine test or an imotest. All tests were read after 72 h by two observers independently. The false-negative rate for the Mantoux was estimated by immediate repetition of the Mantoux in subjects with an initially negative Mantoux but positive multiple-puncture test. When the criterion for a positive reaction was at least 5 mm of induration for the Mantoux and at least 2 mm of induration for the multiple-puncture tests, the false-negative rate of 27% for the imotest was significantly higher than the 4% for the tine and 5% for the Mantoux (p less than 0.001 in each case). Positive multiple-puncture tests were always associated with a Mantoux test that was positive on either the first or second application. Observers agreed in their interpretation of 98% of all tests, and there were no significant differences between testers in frequency of false-negative results for any test. The tine test, when carefully applied and correctly interpreted, gives results which correlate well with those given by the standard Mantoux test. The imotest is less reliable and has no advantages over the tine test.

Clinical Trials as Topic↗
PubMed1982

Bronchoscopic and percutaneous aspiration biopsy in the diagnosis of bronchial carcinoma cell type.

The cell type of bronchial carcinoma predicted from the results of bronchial biopsy at fibreoptic or rigid bronchoscopy or of percutaneous aspiration lung biopsy was compared with the type determined by histological examination of specimens obtained by thoracotomy, biopsy of an extrapulmonary metastasis, or necropsy in 180 cases. The rates of agreement with the final diagnosis were 95.7% for bronchial biopsy through the fibreoptic bronchoscope and 86.5% through the rigid bronchoscope. For percutaneous biopsy, which was usually carried out on tumours inaccessible to the bronchoscope, the rate of agreement was 61%, significantly lower than by the other methods (p less than 0.001). The diagnosis of oat-cell carcinoma by any technique was very reliable. Bronchial biopsy was more reliable than was percutaneous biopsy in diagnosing squamous-cell carcinoma. With any technique the commonest error was the incorrect diagnosis of squamous-cell carcinoma or adenocarcinoma as large-cell undifferentiated carcinoma.

Adenocarcinoma↗
PubMed1982

Fibreoptic bronchoscopy: effect of multiple bronchial biopsies on diagnostic yield in bronchial carcinoma.

The findings in bronchial biopsy specimens obtained at fibreoptic bronchoscopy in 271 patients with bronchial carcinoma were reviewed. Fifty-nine per cent of 703 specimens taken from the site of bronchoscopically visible tumours in 215 patients provided evidence of carcinoma. Unequivocal histological evidence of carcinoma was obtained in 78.6% of the 215 patients with visible tumours. When only one biopsy specimen was taken evidence of carcinoma was obtained in 65.2% of cases. At least five biopsy specimens were required to provide a greater than 90% probability of obtaining at least one positive sample. The anatomical site of the tumour had no significant effect on the proportion of biopsy specimens that were positive or the frequency of obtaining at least one positive sample. When extrinsic bronchial compression was the only visible abnormality evidence of carcinoma was obtained by bronchial biopsy in 26.8% of 56 cases.

Adenocarcinoma↗
PubMed1981

Cryptogenic fibrosing alveolitis. Relationships of pulmonary physiology and bronchoalveolar lavage to response to treatment and prognosis.

A minority of patients with cryptogenic fibrosing alveolitis (idiopathic pulmonary fibrosis) respond to treatment with corticosteroids. The purpose of this study was to identify factors other than histologic features that relate to responsiveness and prognosis. An analysis of 120 patients on whom data were prospectively collected is reported. The relationships between pulmonary function measurements, differential cell counts on bronchoalveolar lavage fluid, physiologic response to treatment, and survival are discussed. Patients responding to treatment with corticosteroids or immunosuppressive drugs had more severe initial impairment of the FVC (p less than 0.0001) and a more recent onset of disease (p less than 0.001). Lavage cell counts showed that increased proportions of lymphocytes were associated with responsiveness to corticosteroids and good prognosis (p less than 0.001), whereas increased eosinophils or increased neutrophils without increased lymphocytes were associated with failure to respond (p less than 0.025), and increased eosinophils were associated with a greater likelihood or progressive deterioration (p less than 0.05). Life table comparisons of survival in different groups showed improved survival in patients responding to treatment (p less than 0.05). Among nonresponders, those with more severe impairment of the FVC had shorter survival (p less than 0.05). We concluded that physiologic and bronchoalveolar lavage data allow predictions of responsiveness to treatment and prognosis that are of practical value to clinicians.

Adult↗