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1.  Lung volumes and flow rates in black and white subjects 
Thorax  1974;29(2):185-188.
Lapp, N. L., Amandus, H. E., Hall, R., and Morgan, W. K. C. (1974).Thorax, 29, 185-188. Lung volumes and flow rates in black and white subjects. It has been known for some time that the vital capacity and forced expiratory volume in one second of black subjects are about 12% lower than those of whites of the same age and height. In the present study, total lung capacity and residual volume were also shown to be decreased by about the same percentage. Expiratory flow rates were similarly decreased, but when the difference in lung size was evened out by matching black and white subjects of the same total lung capacity, no significant differences in flow rates were observed.
PMCID: PMC470126  PMID: 4831524
2.  Urinary hydroxyproline excretion in coalworkers' pneumoconiosis 
Resnick, H., Lapp, N. L., and Morgan, W. K. C. (1969).Brit. J. industr. Med.,26, 135-138. Urinary hydroxyproline excretion in coalworkers' pneumoconiosis. As there is an increased formation of one or all the fibrous proteins in coalworkers' pneumoconiosis, it was felt that a study of the turnover rate of these proteins might shed some light on the pathogenesis of the disease. Urinary hydroxyproline excretion was therefore studied in a group of miners, of whom 19 had simple pneumoconiosis and five had progressive massive fibrosis. No significant deviation from the normal was found.
PMCID: PMC1008907  PMID: 5780105
3.  Significance of irregular small opacities in radiographs of coalminers in the USA. 
The purpose of this study was to determine the factors that are associated with the occurrence of small irregular opacities in the chest radiographs of coalminers, and whether the lung function of miners with irregular opacities differed from that of miners with small rounded opacities, a mixture of small rounded and irregular opacities, or an absence of opacities. A subsample of 6166 coalminers was selected from 9076 miners who had been examined by the US Public Health Service as part of the National Study of Coalworkers' Pneumoconiosis. The subsample consisted of 4479 smokers and 1687 non-smokers. The chest radiograph of each miner was classified according to the UICC/Cincinnati Classification.
PMCID: PMC1008096  PMID: 1268102
4.  Pilot study of closing volume in byssinosis. 
A study of the relative sensitivities of forced expiratory volume in one second (FEV1), maximal mid-expiratory flow (MMF), and closing volume (CV) in the detection of subjects with byssinosis was carried out in a North Carolina cotton mill. Altogether 35 workers participated in the study. Of these, nine showed a decline in FEV1 of 10% or more during the first work shift that followed the weekend break. Twelve subjects showed a decrease in MMF of 15% or more. In contrast only six workers exhibited a 10% increase in closing capacity, while ten showed a 10% increase in CV. Recent evidence of the magnitude of variability in closing volume manoeuvres suggests that our chosen level of change was too low, A 40% change in CV would have identified only five subjects. CV is a more complex manoeuvre for the subject being tested and for the technician to perform, is more time consuming, and is subject to greater variation. To have any advantage over spirometry, CV would have to be appreciably more sensitive. Our study suggests that it is not. However, the MMF may prove to be more sensitive than the FEV1 in the detection of byssinosis.
PMCID: PMC1008065  PMID: 1156572
5.  Variability in the size of airspaces in normal human lungs as estimated by aerosols. 
Thorax  1975;30(3):293-299.
Measurement of persistence, expressed as half-life (t1/2), of a monodisperse aerosol during breath holding was interpreted as an indirect estimate of the size of intrapulmonary airspaces in healthy subjects. Within subject variation of t1/2 measured over a period of nearly two years was small (coefficient of variation 7-7 to 11-5%). Mean effective airspace diameters were calculated from the aerosol t1/2 values using the settling term from the equation of Landahl (1950). Calculated mean airspace diameters ranged from 0-30 to 0-79 mm for 36 males and from 0-40 to 0-62 mm for 12 females. Airspace diameters correlated poorly with age, height, weight, and lung volumes. These results suggest marked differences in airways geometry in subjects with similar heights and lung volumes.
PMCID: PMC470281  PMID: 1145534
7.  Airways obstruction, coal mining, and disability. 
It has recently been suggested that the inhalation of coal in the absence of complicated coal workers' pneumoconiosis (CWP) or smoking can lead to disabling airways obstruction. The cause of such obstruction has been variously attributed to emphysema or bronchitis. The frequency of significant airways obstruction in a group of United States coal miners seeking compensation for occupationally induced pulmonary impairment was therefore determined. In a sample of 611 "Black Lung" claimants there was only one subject who was a non-smoker and who in the absence of other non-occupationally related diseases,--for example, asthma and bronchiectasis--had sufficient airways obstruction to render it difficult for him to carry out hard labour. An alternative explanation for his reduced ventilatory capacity other than coal dust or smoking may be available. If the inhalation of coal dust in the absence of smoking and complicated CWP ever induces sufficient ventilatory impairment to preclude a miner from working, it is indeed rare.
PMCID: PMC1127953  PMID: 8199664
8.  Effect of body position on gas exchange after thoracotomy. 
Thorax  1979;34(4):518-522.
To determine the effect of change in body position on gas exchange after thoracotomy, 12 patients with potentially resectable lung tumours were studied before and 24 hours after operation. Measurements of arterial blood gas tension (PaO2, PaCO2), alveolar-arterial oxygen difference (A--adO2), venous admixture effect (Qs/Qt percent), and physiological dead space to tidal volume ratio (Vd/Vt), were made in the supine, and left and right lateral decubitus positions. Preoperatively, altering position did not affect gas exchange significantly. After thoracotomy in the lateral position with the unoperated side dependent, PaO2 was significantly higher, and A--adO2 and Qs/Qt percent significantly lower than in the supine position. Postoperatively, the lateral position with the side of thoracotomy dependent was usually associated with the worst gas exchange. Only three patients achieved their best postoperative gas exchange in this position. In two this may have resulted from dependent small airway closure during tidal breathing, due to airways obstruction and old age, and in the third from postoperative atelectasis in this unoperated lung. No significant changes in mean PaCO2, Vd/Vt, or minute ventilation (VE) occurred with different positioning.
PMCID: PMC471108  PMID: 505348
9.  Determination of lung volumes from chest films 
Thorax  1970;25(5):544-549.
The results obtained from two radiological methods of determining total lung capacity (TLC) (Kovach's parabo oid and Barnhard's ellipsoid) were compared with those obtained with the body plethysmograph. Determinations of TLC were made in four groups of subjects: group 1 consisted of 26 miners most of whom had simple pneumoconiosis; group 2 consisted of 12 normal subjects; group 3 consisted of eight subjects who had a variety of chest disease, but with no demonstrable parenchymal or pleural opacification; and group 4 consisted of 19 subjects with miscellaneous diseases, all showing demonstrable infiltration or opacification.
The values obtained by the method of Kovach and his colleagues often differed markedly from the plethysmographic determinations, and it became apparent that this method was not sufficiently accurate. On the other hand, the technique of Barnhard and his colleagues gave results that were essentially similar to, and as far as we can say interchangeable with, those obtained by the body plethysmograph in groups 1, 2, and 3. In subjects with marked pulmonary opacification or infiltration, the disparity between Barnhard's method and the plethysmograph tended to be more sizeable. It was concluded that Barnhard's method for determining total lung capacity is accurate and could be applied to epidemiological surveys.
PMCID: PMC472187  PMID: 5489177
10.  Silicosis in surface coalmine drillers. 
Thorax  1983;38(4):275-278.
Surface coalminers are generally thought to be at minimal risk of developing pneumoconiosis. Biopsy-proved silicoproteinosis was found in a 34-year-old surface coalmine driller, and two of nine other drill crew members who worked for the same company had chest radiographic findings compatible with simple silicosis. Reanalysis of data from a previous United States Public Health Service survey of surface coalminers, after exclusion of those with underground mining experience, showed that 38% of the cases of pneumoconiosis occurred in drill crew members, a group comprising only 11% of the study population. On the basis of these data surface coalmine drillers appear to have an increased risk of developing occupational lung disease.
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PMCID: PMC459535  PMID: 6867980

Results 1-10 (10)