Myolipoma in a tethered cord. Case report and review of the literature.

The intradural myolipoma is a very rare tumor, consisting of fully differentiated striated muscle fibers mingled with fat. Only four previous cases have been identified. The authors present a case in which this tumor was associated with a symptomatic tethered spinal cord in an 18-year-old man.

Cellular stress inhibits vascular smooth muscle relaxation.

PURPOSE: Cellular stress has been shown to induce a group of proteins called heat shock proteins (HSPs). Recent evidence suggests that a group of small HSPs may modulate vascular smooth muscle contraction (HSP27) and/or relaxation (HSP20). In this investigation, we hypothesized that cellular stress would alter contraction and/or relaxation of intact vascular smooth muscles and would lead to changes in the induction and/or phosphorylation of the small HSPs. METHODS: Bovine carotid arteries were obtained from an abattoir, and physiologic contractile responses were determined in a muscle bath. Phosphorylation state-specific antibodies were produced and characterized against HSP27. Phosphorylation events were determined with phosphorylation state-specific antibodies or whole-cell phosphorylation and two-dimensional gel electrophoresis. RESULTS: Cellular stress induced by arsenite or heat shock did not alter basal tone or the magnitude of contractions induced by serotonin or high extracellular potassium chloride. However, cellular stress led to inhibition of forskolin and sodium nitroprusside-induced vasorelaxation. This impaired vasorelaxation was associated with increases in the phosphorylation of HSP27 and decreases in forskolin-induced phosphorylation of HSP20. CONCLUSION: Cellular stress, which leads to increases in the phosphorylation of HSP27, inhibits cyclic nucleotide-dependent vascular relaxation and cyclic nucleotide-dependent increases in the phosphorylation of HSP20.

Results and complications after reoperation for failed epilepsy surgery in children.

The seizure outcome and neurological outcome in children who undergo reoperation for failed epilepsy surgery have not been well documented. This retrospective study evaluated 20 children who underwent a second resective surgery for recurrent seizures. Four categories of patients were identified: (1) extension of the initial resection was performed in 8 patients; (2) 5 patients underwent lobectomy or corticectomy in a region remote from the original surgical site; (3) multilobar resection which may have included further resection of the initial procedure was accomplished in 4 patients; (4) hemispherectomy was performed in 3 patients. Patients with reoperation in the same lobe as the first procedure (group 1) had a 62% seizure-free rate, while 44% of patients in groups 2 and 3 were free from seizures at follow-up evaluation. Patients undergoing hemispherectomy had a 67% seizure-free rate. Significant unexpected neurological deficits occurred in 3 patients who underwent multilobar resection at reoperation. Complications included motor and language deficits. Reoperation for intractable partial epilepsy is beneficial in selected children. Patients who require multilobar resections may have higher risk of postoperative neurological deficit than those patients with reoperation in one lobe. These factors may be useful in counseling parents of children considering reoperation for recurrent epilepsy.

Experimental acute subdural hematoma in infant piglets.

Traumatic acute subdural hematoma is associated with high mortality in the pediatric population, yet the pathophysiology remains poorly understood. The objective of this study was to develop a pediatric model of acute subdural hematoma, and to evaluate the resultant histopathological changes in the brain. Ten 3-week-old piglets were studied. A 5-mm craniotomy was made in the right frontal skull. A small silastic tube was inserted through the underlying intact dura into the subdural space. A craniotomy was made posterior to the right coronal suture with underlying dura left intact (closed cranial window model). Injection of 5 ml autologous, nonheparinized blood was accomplished through the silastic tube. Animals were sacrificed after 72 h or 1 week. During the subdural injection, intracranial pressure rose to 62 +/- 8 mm Hg, and returned to baseline within 1 h of surgery. Mean arterial blood pressure increased transiently. Cresyl violet and hematoxylin and eosin staining demonstrated extensive areas of white matter necrosis under the hematoma after 72 h survival (n = 7). Zones of necrosis were also noted in cortex, but were less extensive than those seen in white matter. These results differ from adult rodent models in which cortex is primarily affected. This is the first reported pediatric model of traumatic acute subdural hematoma. This model can be used in future studies to investigate pharmacological or other therapies which may improve outcome after this type of injury.

Deep hypothermia diminishes the ischemic induction of heat-shock protein-72 mRNA in piglet brain.

BACKGROUND AND PURPOSE: Expression of the 72-kD heat-shock protein (HSP72) has served as a useful indicator of ischemic stress after cerebral ischemia. Moderate hypothermia (30 degrees C) has been reported to block the induction of HSP72 after a brief episode of forebrain ischemia. The objective of the present study was to examine the effects of deep hypothermia (15 degrees C) on expression of HSP72 after a prolonged period of cerebral ischemia. METHODS: Piglets 19 to 23 days old, were placed on cardiopulmonary bypass, and brain temperature was lowered to 23 degrees C (n = 9) or 15 degrees C (n = 9) before circulatory arrest for 1 hour. In an additional group of animals (n = 5), the temperature was lowered to 29 degrees C before arrest for 45 minutes. All animals were reperfused at 37 degrees C for 2 hours, and the regional expression of HSP72 mRNA was assessed using in situ hybridization. RESULTS: After ischemia at 15 degrees C, expression of HSP72 mRNA was limited to a few scattered regions of cerebral cortex; the percentage of cortex exhibiting HSP72 mRNA was 23 +/- 7% (mean +/- SEM). Ischemia at 23 degrees C triggered expression of HSP72 mRNA in a significantly larger portion of the cortex (68 +/- 8%, P < .001). Ischemia at 29 degrees C failed to induce substantial expression of HSP72 mRNA in the cerebral cortex. CONCLUSIONS: These results suggest that, relative to ischemia at 23 degrees C, deep hypothermia (15 degrees C) diminishes ischemic alterations leading to induction of HSP72 mRNA. The lack of cortical expression of HSP72 mRNA following ischemia at 29 degrees C may be secondary to inadequate recovery of energy metabolism.

Isolated extranodal intracranial sinus histiocytosis in a 5-year-old boy. Case report.

Sinus histiocytosis with massive lymphadenopathy was first described in 1969 by Rosai and Dorfman. The typical clinical characteristics of this disease include painless cervical lymphadenopathy, fever, and weight loss. The condition can present with an extranodal mass in about 25% of patients, and isolated masses without lymph node involvement occur rarely. The authors describe a 5-year-old boy with cavernous sinus syndrome due to an isolated extranodal form of sinus histiocytosis with massive lymphadenopathy in the temporal fossa. Several cases of this disease involving the central nervous system are reviewed. The histopathological and magnetic resonance imaging characteristics are discussed.

Cytogenetics of postimplantation rabbit conceptuses following delayed fertilization.

The chromosome complement and anatomical development of 10-16-day rabbit embryos were studied following delayed fertilization. Preimplantation loss was 40% in the experimental group compared with 17% in control animals. Also, a greater number of embryos retarded in growth or with structural anomalies was seen in the delayed-mated group. Cytogenetic analysis revealed a trisomy for a small metacentric chromosome in 104 control embryos. Only 1 triploid embryo was found in 84 implantation sites from rabbits that had been delayed mated. The incidence of triploidy postimplantation was much less than the 13% found previously in 6-day blastocyts. Increased embryonic loss at the time of or shortly after implantation may be responsible for the discrepancy.

Pentobarbital sodium and chromosome abnormalities in rabbit blastocysts.

Female rabbits were injected with pentobarbital sodium at 1/4 h or 6 h post coitum. A slight delay in oocyte maturation was evident in animals killed at 17 h pc, however, zygote development appeared normal by 24 h pc. At 6 days pc, a greater frequency of chromosomally abnormal blastocysts was found in animals injected with pentobarbital than in control rabbits.

Allergic management of Meniere disease.

Twenty-eight patients with Meniere disease were selected on the basis of a positive allergic history. Factors other than allergy that might produce the signs and symptoms of endolymphatic hydrops were first diagnosed and controlled with appropriate management. Allergic diagnosis and management consisted of testing and treating inhalant allergies according to the methods of Rinkel. Foods were first tested using the Bryant's modification of Black's cytotoxic food test. All positive foods were eliminated except for those considered extremely difficult to avoid. These were managed using the provocative skin food test and neutralization method of Lee et al. All patients in this study were under allergic management for a period of 14 to 29 months. During this time, labyrinthine symptoms were improved in nine cases and in 19, there was no change.