Search PubMed⌕ Search

Biomedical subjects

M Berkowitz

Publications and source records attributed to M Berkowitz.

31 records · Page 2Linked to original sources
PubMed1981

Autoregulation of thyroid iodide transport: possible mediation by modification in sodium cotransport.

Cat thyroid slices were employed to determine whether preincubation with excess iodide, a procedure previously reported to depress subsequently measured iodide transport activity, is associated with any alteration in the relationship between sodium and iodide transport. Kinetic analysis revealed that the inhibition of iodide-concentrating activity by iodide pretreatment was accompanied by a reduction in the apparent affinity of the iodide transport for iodide as reflected by increase in the value of KA, the concentration of iodide required to achieve half-maximal transport activity. A reduction in extracellular sodium concentration was also accompanied by an increase in the value of KA for iodide transport. Thus, the KA of iodide transport in control thyroid tissue was increased from a value of 8.6 +/- 1.2 to 16.5 +/- 2.4 microM, by a reduction in extracellular sodium from 144 to 52 mM. In contrast, in thyroid tissue subjected to a 2-h preincubation with 30 microM NaI, a similar reduction in extracellular sodium concentration was associated with only a 20% increase in KA from a value of 17.7 +/- 2.4 to 21.7 +/- 2.2 microM. Analysis of the kinetic data suggests that the autoregulatory effect of excess iodide results in a decline in the sodium dependency of iodide transport. This loss of sodium dependency is accompanied by an increase in the affinity of the process for sodium, as well as a reduction in the affinity of the transport system for iodide.

Animals↗
PubMed1979

Occupational safety and health.

Work accidents became a matter of societal concern in the Progressive era of Woodrow Wilson. When other contingencies of modern life were brought under social security in the New Deal reforms of the 1930s, work accident legislation remained separate. One possible reason was that work accidents can be controlled within industrial and chance limits. But control does not imply elimination since a risk-free environment would paralyze production. In spite of imperfections caused by low benefits and imperfect insurance arrangements, the workers' compensation legislation does help internalize the costs of accidents, but internalization of costs is only one remedy. Regulation and a much broader community responsibility are others. It is argued that regulation poses greater problems and that broader community responsibility may evade the issues involved in choosing the appropriate tradeoff point between production and health which will maximize social welfare.

Accidents, Occupational↗
PubMedDate not supplied

Correlation of radiographic and arthroscopic findings with rotator cuff tears and degenerative joint disease.

The purpose of this study was to identify early signs of rotator cuff tear and glenohumeral articular cartilage degeneration by using conventional radiography. A non-weighted anteroposterior oblique and a weighted active abduction view were evaluated for superior humeral migration and matching degenerative changes at the inferolateral acromion and superior aspect of the greater tuberosity in 40 patients who underwent shoulder arthroscopy. Measurements of the glenohumeral distance were performed. Surgical reports were reviewed to determine rotator cuff and glenohumeral articular cartilage status. Matching degenerative changes correlate with complete rotator cuff tear (P =.04); superior migration does not. Severe glenohumeral cartilage loss correlates with narrowing of the superior joint space on the anteroposterior oblique radiograph (P =.02) and with narrowing of the mid joint space on the active abduction view (P =.05). Both glenohumeral articular cartilage degenerative change and rotator cuff injury, before formation of typical sequelae of chronic rotator cuff tear, can be detected with the use of conventional radiography.

Adult↗
PubMedDate not supplied

Ventilatory function in cervical and high thoracic spinal cord injury. Relationship to level of injury and tone.

Weakness and spasticity of chest wall muscles are known to adversely affect pulmonary function in spinal cord-injured patients. To test the assertion that impaired strength and increased tone contribute to ventilation deficits, 52 patients with recent acute traumatic cervical and high thoracic spinal cord injury underwent complete pulmonary function testing. Regression analyses were performed to determine relationships between spinal cord injury level and pulmonary function test results and between Ashworth scale tone ratings and pulmonary function test results. Level of injury was found to be significantly correlated with expiratory reserve volume (and percent predicted expiratory reserve volume), residual volume/total lung capacity ratio, and negative inspiratory pressure but not with vital capacity, forced expiratory volume in one second, forced expiratory volume in one second/vital capacity ratio, inspiratory capacity, total lung capacity, functional residual capacity, residual volume, or positive expiratory pressure. There were significant correlations between Ashworth Scale tone ratings and negative inspiratory pressure but not between tone ratings and any of the other pulmonary function test results. It appears that muscle strength may be a more important factor than muscle tone in determining pulmonary function in spinal cord-injured patients and that both strength and tone are closely related to negative inspiratory pressure.

Adolescent↗
PubMedDate not supplied

Loriemil Villa Prado.

Explore the source record for details and available documents.

Congresses as Topic↗