Biomedical subjects
Publications and source records attributed to J Costello.
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The study of the carcinogenic potential of domestic U. S. shale oil has increased significantly in importance because of the present energy problem and resulting research into alternative sources of fuel. With the increased scope of planned oil shale activity on the Colorado Plateau, it is important that an attempt be made to determine the health effects, if any, of occupational exposure to shale oil. This paper briefly reviews some past work of Soviet and British investigators concerning potential health hazards of shale oil. It reviews the results and conclusions of the 1952-1955 dermatological study of oil shale workers by the U. S. Public Health Service, and it discusses in detail the plans of a NIOSH morbidity and mortality study currently under way.
An area of major concern in considering increased coal production and utilization is the health and safety of increased numbers of workers who mine, process, or utilize coal. Hazards related to mining activities in the past have been especially serious, resulting in many mine related accidental deaths, disabling injuries, and disability and death from chronic lung disease. Underground coal mines are clearly less safe than surface mines. Over one-third of currently employed underground miners experience chronic lung disease. Other stresses include noise and extremes of heat and cold. Newly emphasized technologies of the use of diesel powered mining equipment and the use of longwall mining techniques may be associated with serious health effects. Workers at coal-fired power plants are also potentially at risk of occupational diseases. Occupational safety and health aspects of coal mining are understood well enough today to justify implementing necessary and technically feasible and available control measures to minimize potential problems associated with increased coal production and use in the future. Increased emphasis on safety and health training for inexperienced coal miners expected to enter the work force is clearly needed. The recently enacted Federal Mine Safety and Health Act of 1977 will provide impetus for increased control over hazards in coal mining.
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Theophylline disposition (clearance, volume of distribution, and half-life) was measured in 31 normal volunteers and 26 acutely ill patients with airway obstruction within 24 hours of hospital admission and again when intravenous aminophylline was discontinued 2 to 10 days later. Sex, age, race, the diagnosis of asthma, and the diagnosis of chronic bronchitis were not significantly correlated with clearance. Clearance was significantly increased in smokers and significantly decreased in patients with congestive heart failure, pneumonia, and severe bronchial obstruction. The volume of distribution was not correlated with these variables. Within 24 hours of admission, the mean clearance in our patients without congestive heart failure or pneumonia was 44.5 ml per hour per kg of body weight, 40 per cent less than the value on which the widely used 0.9 mg per kg per hour dosage is based. The unexplained interindividual variability of clearance was significantly higher amont patients than control subjects, but intraindividual variability in clearance was not different in these 2 groups after correction for the effects of smoking, congestive heart failure, and so on. Large variability in clearance among patients makes the plasma theophylline concentration resulting from any dosage relatively uncertain. Based on the the results of this study, recommendations are made concerning theophylline dosage computation, and the clinical circumstances calling for determination of plasma theophylline concentrations.
Pleural effusion from metastatic malignancy can cause major impairment of respiratory function and eventual death. Although cure is not possible, successful palliative treatment allows months to years of productive life, obviating the need for continuous hospitalization and repeated thoracenteses. Successful palliative treatment requires obliteration of the pleural space. Literature survey indicates that a wide variety of medical agents and surgical methods have been used with variable success. Medical methods include instillation of antineoplastic agents, antimicrobial agents, or colloidal radioisotopes into the pleural space; quinacrine and tetracycline are moderately to highly effective agents, but the toxicity of the former is substantial. Bedside talc poudrage with thoracostomy-tube drainage is a safe and highly effective alternative. Pleurectomy is the definitive method of preventing reaccumulation of pleural fluid that results from metastatic malignancy, even when other methods have failed, but thehigh morbidity and mortality of the procedures mandate careful patient selection.
The effects of altered acid-base balance on the production of urea and the metabolism of glutamine were investigated in the isolated perfused liver and hindquarter of the rat. In the isolated perfused rat liver, lowering of perfusate pH without altering bicarbonate concentration significantly reduced urea production and increased net glutamine synthesis, although the converse did not obtain. In the isolated perfused rat hindquarter when perfusate pH and bicarbonate were simultaneously reduced glutamine synthesis was significantly increased. The combined hepatic and muscle increase in glutamine synthesis accounted for 89% of the decrease in hepatic urea synthesis under these experimental conditions. These changes in nitrogen metabolism are interpreted in terms of adaptations which offset the initial alterations in hydrogen ion homeostasis.
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Incorrect articulation responses and inappropriate off-task behaviors occurring during programmed articulation instruction were concurrently modified by the presentation of an identical punishing stimulus for both groups of behaviors or by the presentation of different punishing stimuli for each group of behaviors. Results indicated that both procedures were equally effective in reducing both groups of undesirable behaviors. The nature of the relationship between articulation responses and off-task behaviors is discussed in detail, especially in terms of behavioral covariation.
A comparison was made between the effects of punishment combined with positive reinforcement and reinforcement alone for the reduction of incorrect articulation responses. Three different punishers (a buzzer, response cost, and "No!") were studied for six young children while they were receiving programmed articulation instruction. The results indicated (1) that punishment in combination with positive reinforcement was generally more effective than positive reinforcement alone; (2) that whether or not a particular stimulus acted as a punisher could be determined only be empirical demonstration; and (3) that the introduction of punishment contingencies did not produce increased rates of disruptive, off-task behaviors. Conversely, off-task behaviors tended to increase in rate when punishement contingencies for articulation responses were removed.
The effectiveness of articulation remediation procedures based on distinctive feature theory was evaluated through the administration of an articulation program designed for this purpose. Two preschool children with multiple phoneme errors which could be described by a distinctive feature analysis were the subjects. Both children substituted stop phonemes for most continuant phonemes. Each child was individually administered the distinctive feature program which is described in full. Data are presented which indicate the adequacy of the treatment program, the acquisition of correct articulation of the two directly treated target phonemes, and the concurrent improvement of five other nontreated error phonemes. Such across-phoneme generalization was predicted by distinctive feature theory. Certain modifications in the treatment program are suggested and theoretical/empirical questions regarding articulation remediation from a distinctive features viewpoint are discussed.
Three young children were taught correct articulation of an error phoneme on a program administered by their mothers in their homes. During the course of the treatment program each child was periodically brought into the speech clinic where the generalization of correct articulation learned in the home treatment setting could be measured in a series of four settings which differed from the treatment setting in varying degrees. Stimulus words which had not been taught during the home articulation program were also included in generalization testing. The results indicated (1) that correct articulation generalized to a high extent to the nontreatment settings investigated; and (2) that responses to new stimulus words were less adequate than responses to words which had received previous training. The clinical implications of these findings are discussed.
Isophthalic acid, 5-carboxy-, 5-hydroxy-, 5-methoxy-, 5-fluoro-, 5-bromo-, 5-cyano-, and 5-methylisophthalic acid were inhibitors competitive with L-glutamate for bovine liver glutamate dehydrogenase. The extent of inhibition by the derived compounds was not much greater than that obtained with the parent compound, isophthalic acid. A plot of pKi versus pH showed the presence of an ionizable group (pKa 7.4-7.8) at the enzyme active site which interacted with the substitutent at the 5 position of the substituted isophthalates.
A simple method is described for the measurement of urinary oxalate. Oxalate decarboxylase is coupled with NAD+ requiring formate dehydrogenase and the result recorded spectrophotometrically. Accurate determination can be carried out either on urine or a citrate extract or urine. Using the citrate extract procedure, the urinary samples can be stored for at least 3 months without any effect on the oxalate content.
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A successful application of time-out procedures is illustrated by three case studies with high school and college-age male stutterers. The method of administering the time-out procedure is described in detail, and typical results are illustrated by data collected from clinical sessions. Modifications of the basic procedure are tested and their results discussed.