PubMed Health⌕ Search

Biomedical subjects

S T Dull

Publications and source records attributed to S T Dull.

4 recordsLinked to original sources
PubMed1995

Eosinophilic granuloma of the adult spine: a case report and review of the literature.

A 35-year-old patient who had progressive neck and shoulder pain and was neurologically intact was shown to have a C3 vertebral body osteolytic lesion. Open biopsy demonstrated an eosinophilic granuloma. The lesion was treated with external beam radiotherapy (1,000 cGy total dose). This case represents the thirteenth adult spinal eosinophilic granuloma reported in the literature. Spinal eosinophilic granuloma occurs more commonly in children. The characteristics of the 13 adult spinal eosinophilic cases reported suggest differences between the adult and childhood forms. Though rare, eosinophilic granuloma of the adult spine should be considered in the differential diagnosis of spinal osteolytic lesions.

Adult↗
PubMed1991

Severe head injury: effect upon cellular immune function.

Infection is a major cause of morbidity following severe head injury. Although investigations have demonstrated central nervous system modulation of immune function, the effects of severe head injury on immune activity have not been well documented. This study prospectively investigated cellular immune function in 20 patients with isolated severe head injury. In vivo cellular immune status was determined by responses to delayed-type hypersensitivity (DTH) skin tests. In vitro studies included the effect of the lymphocyte mitogen, phytohaemagglutinin (PHA), on peripheral blood lymphocyte (PBL) phenotype expression and PBL blastogenesis. DTH skin testing demonstrated anergy to all antigens used during the first two weeks following head injury. Analysis of PBLs incubated with PHA demonstrated a decrease in the percent of PBL blastogenesis (p = 0.002), the percentage of cells marking as T-cells (p = 0.018), helper T-cells (p less than 0.001) and those expressing interleukin-2 receptors (p less than 0.001). There was a significant increase in the percentage of cells that marked as monocytes (p = 0.030), whereas there was no significant change in the percentage of B-cells, suppressor/cytotoxic T-cells, natural killer cells or in cells expressing the HLA-DR antigen. The infection rate was 55% with most occurring within 5 days of injury. The results of this study suggest that isolated severe head injury causes suppression of cellular immunity. The decrease in PHA stimulated PBL blastogenesis, helper T-cell phenotypic and interleukin-2 receptor expression, suggests suppression in early helper T-cell activation may be responsible for the high incidence of infection following severe head injury. The possible significance of increased monocyte phenotypic expression is discussed.

Adolescent↗
PubMedDate not supplied

Amplitude and latency characteristics of spinal cord motor evoked potentials in the rat.

The motor evoked potential (MEP) has become a valuable component of neurophysiological monitoring. A better understanding of the characteristics of the normal MEP is needed before one can fully appreciate the effects of injury on the MEP. We describe characteristic patterns of spinal cord MEPs, recorded epidurally, in response to transcranial (dura-to-palate) brain stimulation in a rat model. Series of signal averaged MEP responses at a duration of 100 microseconds were recorded at T10/11, T12/13, and L1/2 in 8 normal rats. We used a much greater range of current intensities (0.5-65 mA) than has been studied previously. Also, we studied the gradual development of the MEP wave form using smaller increments of current strength than have been reported previously. We confirmed in rats our earlier report in cats that long latency peaks appear first at low intensities while short latency peaks appear with higher intensities (Konrad et al. 1988). We also report average peak latencies over the range of stimulus intensities used for each recording level in each rat. In some rats, conduction velocities of several MEP peaks were calculated, and they range from 35 to 42 m/sec. These velocities are consistent with values reported in the literature for extrapyramidal pathways. Our rat model provides a method of measuring spinal cord potentials at three levels with no trauma to the spinal cord. Therefore, it can be used to repeatedly test motor function in chronic studies of spinal cord injury.

Animals↗