Social support,self‐efficacy and trauma in new recruits and experienced firefighters

This study compared new fire recruits in the first week of employment and following a 10‐week training period with a group of experienced firefighters. Results suggest that new firefighter recruits enter the fire service with considerable experience of exposure to critical events. Nevertheless, a significant linear relationship was found between years of experience and levels of traumatic stress and depression. Further, this study revealed that experienced firefighters had lower levels of social support and lower self‐efficacy than the new recruits. As these variables were associated with traumatic stress and depressive symptoms, it is concerning that these protective factors appear to diminish with time. Copyright © 2003 John Wiley & Sons, Ltd.     

Left main bronchial-esophageal fistula: A complication of bronchial artery embolization

Left bronchial-esophageal fistula is a rare complication of bronchial artery embolization. A case is presented with pathologic correlation. The pathophysiology of this complication is discussed as well as recommendations on how it may possibly be avoided.     

Molecular and Serological Differentiation of Staphylococcal Exfoliative Toxin Synthesized Under Chromosomal and Plasmid Control

Evidence for the existence of two molecular species of exfoliative toxin (ET) synthesized by phage group II Staphylococcus aureus under chromosomal and plasmid control is presented. Serological evidence that these molecular species of toxin are distinct from each other is given. The plasmid-controlled toxin was synthesized along with the chromosomally controlled toxin by the group II UT0002 strain, whereas another group II strain, UT0007, synthesized only the plasmid-controlled toxin. The molecular weight of the plasmid-controlled toxin was slightly less than that of the chromosomally controlled type and could be separated from the latter on 12.5% sodium dodecyl sulfate (SDS)-polyacrylamide slab gels. On 7.5% SDS-polyacrylamide cylindrical gels there was no hint of heterogeneity, and both ETs migrated together as a single homogeneous band. The existence of two serotypes of ET among phage group II strains complicates interpretation of previous work in this field and makes necessary the preparation of two different antigens for radioimmunobinding assays. Discovery of these ET serotypes provided an explanation for previously reported low binding by rabbit hyperimmune serum (B. Wiley, L. Glasgow, and M. Rogolsky, Infect. Immun. 13:513-520, 1976) in the radioimmunobinding test. A molecular species of ET differing from each of the other two serotypes was isolated from cultures of a phage group III S. aureus. This ET produced scalding in suckling mice and was lower in molecular weight than the ET produced under plasmid control by group II strains. Preliminary serological studies indicated that the ET in the group III strain is closely related to or possibly identical to the group II toxin produced under plasmid control.     

Immunosuppression and toxoplasmic encephalitis: Clinical and experimental aspects

Encephalitis developing after prolonged antineoplastic therapy in two patients with Hodgkin's disease and in one with multiple myeloma was found at autopsy to be caused bi toxoplastnosis. To better understand the pathogenesis of the brain lesions, ranging from microscopic foci to some having a diameter of 6 cm. and characterized by proliferation of the organisms at the margins of expanding necrosis, an animal model was studied. Similar lesions were produced in hamsters by inducing relapse of chronic latent toxoplasmosis through administration of cortisone, cyclopliospliamide, or whole body irradiation, but toxic doses of nitrogen mustard and urethane did not precipitate relapse. Notably, relapsing toxoplastnosis generally involves the brain exclusively, suggesting a special susceptibility related to immune mechanisms. The roles of cells and of antibodies in immune surveillance against this chronic infection in otherwise normal hosts are considered. In man the suppression of cellular immunities by certain antineoplastic agents would seem to be decisive in causing relapse of toxoplasmosis, rather than the replacement of immunologically active cells by neoplasm. Because the infection can be controlled with sulfadiazine and pyrimethamine, a high index of suspicion is essential to detect incipient cerebral toxoplasmosis. Serial serologic testing is helpful by demonstrating titer elevations; however, poor antibody production or transferred antibody may be misleading clinically when single tests are evaluated. Similarly, a poor inflammatory cell response can make it difficult for the histopathologist to detect small lesions in these patients.     

Effects of hexamethonium, biperiden and phentolamine on the vasoconstrictive effects of oculomotor nerve stimulation in rabbits.

The surface ultrastructure of epithelial cells of the mature lens and their contiguous layers, the capsule and developing cortical fibers were studied by scanning electron microscopy. The cells of the concentric zones of the epithelium (central, intermediate and equatorial) display significant differences in size, shape and fine surface morphology. The three-dimensional aspects of their association with the capsule and the underlying cortical fibers are shown and discussed. The basal lamina of the capsule appears to be attached to the underlying epithelial cells along the cell borders and, in the central-intermediate zones, at various points on the cell surfaces. The developing cortical fibers show button-shaped structures and depressions on their surfaces and complex patterns of elongate cellular projections.     

Thyroid Function in Normals: Influences on the Electroencephalogram and Cognitive Performance

Recently it has been suggested that thyroid function may influence neuropsychological processes not only as a result of thyroid disease but also through normal neurophysiologic adaptive mechanisms. In 69 normal university students, levels of thyroid stimulating hormone (TSH), thyroxine (T4), and triiodothyronine (T3) were assayed in blood samples and related to measures of cognitive performance and to spectral measures of the EEG recorded during cognitive performance. Significant relationships were found between T3 levels and delta power in the EEG from occipital leads, with higher T3 associated with less EEG power in the left hemisphere and greater power in the right hemisphere. Higher T3 levels were associated with poorer performance on several cognitive tasks, particularly for males, although the males with higher T3 levels also showed faster correct responses on a word fluency task. These results seem to support the hypothesis that an individual's characteristic level of thyroid function is relevant to normal neuropsychological processes.