Isolated intracranial involvement in Rosai-Dorfman disease: a report of two cases and review of the literature

Rosai-Dorfman disease is an idiopathic histiocytic disorder of lymph nodes and extranodal sites. Central nervous system manifestations of this disease are rare, and to our knowledge only 16 cases of intracranial involvement have been reported previously. Intracranial Rosai-Dorfman disease clinically and radiologically resembles meningioma, and histologic examination is essential for a definitive diagnosis. We report two cases of isolated, intracranial, dural-based Rosai-Dorfman disease, review the literature, and discuss the differential diagnoses of this lesion.

MRI monitoring of interstitial microwave-induced heating and thermal lesions in rabbit brain in vivo

The purpose of this experiment was to use MRI to monitor microwave heating and thermal damage of brain tissue in vivo. Interstitial microwave antennas were implanted into the cerebral hemispheres of seven anesthetized rabbits. Variable power of 30 to 100 W was applied for periods of 5 to 15 minutes and tissue temperature was monitored continuously. MR images were obtained throughout the procedure at 20-second intervals, using a spoiled gradient-echo sequence, without significant artifact. Magnitude, phase, and complex difference images all demonstrated temperature-related signal changes during heating. The findings were better visualized on the phase and complex difference images. Phase difference image analysis revealed an approximately linear relationship between phase change and temperature. Post-treatment thermal lesions measured up to 2.0 cm in size on pathologic specimens and exhibited a zonal pattern on spin-echo MR images.

Primary intramedullary primitive neuroectodermal tumor of the spinal cord: case report and review of the literature

OBJECTIVE AND IMPORTANCE

Primary intraspinal primitive neuroectodermal tumors (PNETs) are rare. We report a case and review the literature.

CLINICAL PRESENTATION

A 22-year-old woman presented with rapidly progressive paraparesis and neurogenic bladder.

INTERVENTION

Preoperative computed tomography myelograms revealed a complete block at T12-L1, consistent with an intramedullary lesion. An urgent operation was performed with gross total tumor removal. The pathological findings were consistent with a PNET. Recurrence was noted within 10 weeks of surgery and has been somewhat responsive to chemotherapy and radiotherapy thus far. A review of the English literature shows that only 13 cases of primary intraspinal PNETs have been reported to date, and the present case is the second one in which the tumor was purely intramedullary. Most of the reported patients survived less than 2 years.

CONCLUSION

Primary intraspinal PNETs are rare tumors and carry a poor prognosis.

Motor and sensory specificity of host nerve axons influence nerve allograft rejection

Previous studies have shown both survival and loss of regenerated host axons within nerve allograft segments after withdrawal of Cyclosporin A (CsA) immunosuppression. We hypothesized that the nature of end-organ reinnervation may influence the response of the axon, with survival of axons for appropriate innervation vs degeneration for inappropriate innervation. The rat femoral nerve model was chosen, as it has approximately equal sensory (S) and motor (M) divisions. Four ACI rat peroneal nerve allografts were sutured in straight (right leg: MM and SS) or switched (left leg; MS and SM) orientation in each femoral nerve transection gap in each Lewis rat recipient. Rats received CsA for 8 weeks to allow end-organ reinnervation, after which immunosuppression was discontinued. Rats were killed at various times thereafter, and underwent histologic and morphometric analysis of the graft segment axons. The regenerated axon population in the allograft reflected the nerve of origin: significantly more but smaller fibers when the proximal nerve was sensory and fewer but larger fibers when the proximal nerve was motor. After CsA withdrawal, there was a marked decrease of host axons as part of an ensuing rejection episode. The overall proportional decrease of axons was similar across all nerve orientation groups and, therefore, did not appear to be influenced by the nerve of origin or by the end-organ. However, the sensory proximal groups (SS and SM) contained more mature, noninjured fibers, while the motor proximal groups (MM and MS) contained significantly more degeneration and newly regenerating axons. We conclude that the motor or sensory nerve origin of the host axon, rather than the end-organ, influences axon survival after immunosuppression cessation. It is hypothesized that sensory axons may be more resilient while motor axons are selectively vulnerable to this second injury.

Cavernous malformation presenting as an extra-axial cerebellopontine angle mass: case report

OBJECTIVE AND IMPORTANCE

We describe a rare case of an extra-axial cavernoma of the cerebellopontine angle without internal auditory canal involvement and with an unusual appearance on preoperative magnetic resonance imaging (MRI). Only three cases of cerebellopontine angle cavernomas have been previously reported, and none of these reports included preoperative MRI.

CLINICAL PRESENTATION

A young man presented with subacute left facial hypesthesia and chronic asymmetrical sensorineural hearing loss. MRI revealed a mass, which was isointense on T1- and T2-weighted images, with evidence of hemorrhage (methemoglobin and hemosiderin). The lesion did not enhance after the injection of gadolinium.

INTERVENTION

The lesion was removed without difficulty by a suboccipital approach, with intraoperative electrophysiological monitoring of facial and cochlear nerves. Facial paresis cleared postoperatively.

CONCLUSION

The present case suggests that the appearance of cerebelopontine angle cavernomas as revealed by MRI may be similar to that of intraparenchymal cavernomas. This is in contrast to previously reported cases of extra-axial cavernomas at other sites. Evidence of hemorrhage in an extra-axial lesion revealed by MRI suggests a possible diagnosis of cavernoma.

Anti-CD18 antibodies improve cardiac function following cardiopulmonary bypass in dogs

PURPOSE

Cardiopulmonary bypass is associated with activation of neutrophils, which may adhere to vascular endothelium causing lung, heart, and brain injury. We tested whether blocking neutrophil adherence would improve organ function following cardiopulmonary bypass in dogs.

MATERIALS AND METHODS

All dogs received a standard anesthetic, and then one group (n = 6) received 2 hours of cardiopulmonary bypass followed by 4 hours of observation. A second group (n = 6) received a monoclonal antibody (6 mg/kg) to CD18, a neutrophil adherence factor, immediately before cardiopulmonary bypass. A third group (n = 6) did not receive cardiopulmonary bypass or antibody.

RESULTS

Using flow cytometry we found that the antibody bound essentially all neutrophil CD18 sites. All three groups had similar gas exchange and hemodynamics. Lung and heart histology results were similar between groups. By echocardiography, five animals receiving cardiopulmonary bypass alone showed regional wall abnormalities, whereas only one receiving antibody showed wall motion abnormality (P < .05). Following cardiopulmonary bypass, intracellular myocardial pH was higher (P < .05) in the antibody-treated group compared with the group that had cardiopulmonary bypass alone (7.23 +/- 0.05 v 7.07 +/- 0.07 respectively).

CONCLUSION

Monoclonal antibodies to CD18 can prevent the deterioration in cardiac function routinely observed following cardiopulmonary bypass.

Postirradiated and nonirradiated gliosarcoma: immunophenotypical profile

BACKGROUND

Thirty-one gliosarcomas (25 nonirradiated and 6 postirradiated tumors) were selected based on the presence of two distinctive areas: a malignant gliomatous and a sarcomatous component. In all cases, the sarcomatous component appears like fibrosarcoma or malignant fibrous histiocytoma. Two tumors showed additional areas consisting of osteochondroid differentiation.

METHODS

All tumors were examined using antibodies against Ulex europaeus agglutinin I (UEA), glial fibrillary acidic protein (GFAP), vimentin (VM), epithelial membrane antigen (EMA), desmin, collagen IV, alpha-1-antitrypsin (alpha-1-AT) and smooth muscle actin (SMA).

RESULTS

While the VM highlighted the sarcomatous areas of all tumors there were only scattered spindle cells that were GFAP-positive in the same areas. The alpha-1-AT was diffusely reactive in the sarcomatous areas in 20 cases. Focal immunoreactivity was seen with SMA (20 tumors), UEA (8 tumors), EMA (5 tumors), collagen IV (5 tumors) and desmin (4 tumors) in the nonvascular sarcomatous cells.

CONCLUSIONS

The range of immunophenotypical expression is likely to be a reflection of the capacity of a multipotential progenitor to undergo divergent differentiation. There is a very little morphological difference between the postirradiated and nonirradiated tumors except that a higher proportion of postirradiated tumors are immunoreactive to SMA and desmin.

Massive pulmonary tumor emboli in a sarcoma. An unusual cause of sudden death

Although metastatic spread of tumor to the lungs is common, massive pulmonary tumor emboli are very unusual. Most tumor emboli originate from epithelial-derived tumors. Only a few cases of pulmonary embolism from sarcomata have been reported. We herein describe the case of a 36-year-old woman who died suddenly due to massive pulmonary tumor emboli from a retroperitoneal malignant mesenchymoma. We believe this is the first case report of a mesenchymoma causing sudden death due to massive tumor embolism.

Spontaneous rupture of thoracic aorta through an atheromatous plaque: case report and literature review

Spontaneous rupture of thoracic aorta without aneurysm formation is extremely rare. A case of spontaneous rupture through an atheromatous plaque in an 82-year-old woman is reported. She presented with atypical chest pain, and chest radiography revealed no evidence of aneurysm. She died suddenly in the hospital within 24 h after admission. At autopsy, there was an intimal tear and rupture of the descending aorta through an atheromatous plaque, resulting in massive hemothorax. The previous reported cases of spontaneous aortic rupture were reviewed. The pathology of spontaneous aortic rupture are discussed with emphasis on the dating of the rupture, which may have significant medicolegal importance.

Narcolepsy secondary to fourth ventricular subependymoma

BACKGROUND

Secondary (symptomatic) narcolepsy is rare. We report a subependymoma of the fourth ventricle associated with narcolepsy. The patient was a 50-year old woman with a long history of narcolepsy who died of colonic carcinoma with no cerebral metastasis. She was positive for HLA-DR2. At autopsy there was a tumour dorsal to the fourth ventricle which involved the midbrain tectum and rostral pons. Histologic examination of the tumour confirmed it to be a subependymoma.

METHODS

Review of the previous cases of secondary narcolepsy was made with particular reference to the anatomical location of the lesions.

RESULTS

Most of the lesions were found around the third ventricle and rostral brainstem.

CONCLUSIONS

Knowing the anatomical localization of the pathological changes in secondary narcolepsy could be important in improving our understanding of its pathogenesis.

Pontomedullary rent. A specific type of primary brainstem traumatic injury

Pontomedullary rent is a primary injury to the brainstem that may occur in high-speed accidents. We present a series of 13 autopsies with complete or partial pontomedullary rent documented over a 12-year period. Of the 13 cases, seven had associated basal skull fractures and three had fractures of the cervical spine. In five patients, the rent was an isolated traumatic lesion of the brain. While pontomedullary rents are mostly caused by traumatic craniocervical hyperextension, some authors feel that these rents could be a form of diffuse axonal injury caused by angular acceleration of the head. In this study, two patients had documented features of diffuse axonal injury. More than one mechanism of injury could therefore be involved. Pontomedullary rents could be underdiagnosed, as partial rent is compatible with survival and, when there are no associated fractures, these tears may be attributed to artifactual damage occurring during removal of the brain at autopsy.

Polyamines in human brain: regional distribution and influence of aging

Although much evidence has implicated polyamines in brain development and function, little information is available on these substances in human brain. We examined the influence of regional distribution and aging on putrescine, spermidine, and spermine levels in autopsied human brain. In the adult brain, concentrations of spermidine were the highest, followed by spermine and putrescine. All three polyamines showed a distinct and uneven distribution profile among the 10 examined brain areas. Spermidine levels were especially high in white matter and thalamus (20 and 9.3 nmol/mg of protein, respectively), whereas spermine concentrations were highest in cerebellar cortex (3.4 nmol/mg of protein). High levels of putrescine were observed in cerebral cortices, putamen, and hippocampus (0.7-1.2 nmol/mg or protein), with lowest levels in cerebellum and thalamus (0.3-0.5 nmol/mg of protein). No statistically significant influence of aging (1 day to 103 years; n = 57) on either putrescine or spermine levels in occipital cortex was observed. In contrast, spermidine levels increased markedly from birth, reaching maximal levels at approximately 40 years of age (+228% increase in the mean 41-year-old group vs. 6-week-old group), which were maintained up to senescence. These observations in human brain thus differ from those reported in the rodent, in which levels of all three polyamines show a pronounced postnatal reduction. Our data support the notion that polyamines may have roles in both postnatal brain development and in mature brain function.

Clinicopathologic features of primary and postirradiation cerebral gliosarcoma

BACKGROUND

Gliosarcoma is an uncommon malignant brain tumor with mixed glial and mesenchymal elements. Experience is limited to case series, and pathologic data are disparate, leading to uncertainty about clinical features, management, and histogenesis.

METHODS

A clinicopathologic review of 32 patients with survival analysis and immunohistochemical studies was performed including glial fibrillary acidic protein analysis, alpha-1-antitrypsin (alpha-1-AT) analysis, and smooth muscle actin (SMA) analysis.

RESULTS

Twenty-five patients had primary gliosarcoma, whereas 7 developed gliosarcoma after irradiation for glioblastoma multiforme (GBM). Clinical features were similar to those of GBM. Most tumors were intraaxial and diffusely infiltrating by radiologic studies and at surgery. Median survival for primary gliosarcoma was 25 weeks overall, with patients who received irradiation surviving longer (46 vs. 13 weeks, P < 0.025). Gliosarcoma occurring after irradiation appeared hyperdense by computed tomography in five of seven cases, and median survival was 53 weeks. Primary gliosarcoma was a dimorphic tumor with malignant glial elements and features of malignant fibrous histiocytoma (MFH) or fibrosarcoma and one osteosarcoma. Smooth muscle actin labeled tumor vessels heavily, but in 15/25 primary cases, it extended to the surrounding spindle cells. The remaining cases appeared morphologically like MFH and tended to be positive for alpha-1-AT. Postirradiation gliosarcoma was fibrosarcomatous with positive SMA in 75% of the cases examined.

CONCLUSIONS

Gliosarcoma behaves clinically like GBM, and survival may be improved by cranial irradiation of selected patients. Smooth muscle actin reactivity in sarcomatous areas suggests histogenesis in some tumors from the smooth muscle within GBM, whereas others may arise via different mechanisms including differentiation from a pluripotential precursor. Transformation of the smooth muscle within GBM may have therapeutic implications for antiangiogenesis agents.

Peptidergic neurons of subcortical white matter in aging and Alzheimer's brain

Most of the neurons in the subcortical white matter of the adult cerebrum are remnants of the transient subplate cortex which appears during early cortical development. The peptidergic neurons in the subcortical white matter, beneath the striate cortex were examined qualitatively and qualitatively with immunohistochemistry for substance P, cholecystokinin, somatostatin and neuropeptide Y in seven control patients and eight patients with Alzheimer's disease. The different peptidergic subcortical neurons still persisted in normal aging. In Alzheimer's disease, however, the substance P- and somatostatin-immunoreactive neurons were decreased in numbers and showed degenerative changes.

Association of infantile neuroaxonal dystrophy and osteopetrosis: a rare autosomal recessive disorder

The association of neuroaxonal dystrophy and osteopetrosis is reported in 2 siblings born to non-consanguineous parents. The 1st child was diagnosed as having infantile osteopetrosis shortly after delivery. A computed tomography scan of the head revealed agenesis of the corpus callosum. She died at the age of 9 months. Post-mortem examination showed pneumonia and bony sclerosis. Neuropathological examination revealed cerebral atrophy, ventricular dilation, absence of the corpus callosum, and a small hippocampus. Neuroaxonal spheroids were found in hippocampus, basal ganglia, pons, medulla, spinal cord, cranial nerves, cerebellum, and peripheral nerves. Ultrastructural examination revealed membranous cytoplasmic bodies and electron-dense granular deposits within the neuroaxonal spheroids as well as the soma of neurons. The 2nd child was delivered at 36 weeks of gestation because of intrauterine fetal distress. The diagnosis of osteopetrosis and partial agenesis of the corpus callosum was made shortly after delivery. The child died at 1 month without an autopsy. There are rare cases reported previously with the association of neuroaxonal dystrophy and osteopetrosis. We review these cases and compare them with ours.

Amyotrophic lateral sclerosis: correlation of clinical and MR imaging findings

PURPOSE

To determine the magnetic resonance (MR) imaging characteristics of amyotrophic lateral sclerosis (ALS) and to evaluate possible correlations between the disease severity and the MR imaging findings.

MATERIALS AND METHODS

The authors retrospectively reviewed MR images of the head in 17 patients with ALS (14 men and three women) and 17 age-matched control subjects. The corticospinal tract (CST) was analyzed for the following features: size, signal intensity, and number of sections and regions in which the CST could be seen.

RESULTS

Patients with ALS demonstrated sharp, well-defined, round, symmetric lesions that were hyperintense to gray matter within the CST. The lesions were best seen at the level of the middle or lower internal capsule on T2-weighted images. Visualization of the CST on proton-density-weighted images (which occurred in eight ALS patients) is the most reliable MR finding. Low signal intensity was identified within the motor cortex in six patients. Positive MR findings correlated with average or rapid progression of the disease.

CONCLUSION

Increased signal intensity in the CST on proton-density-weighted MR images is diagnostic for motor neuron disease and correlates with the rate of disease progression. Subtle ALS changes can be differentiated from the normal CST. Low signal intensity in the motor cortex on T2-weighted images is a useful finding.

Proliferating cell nuclear antigen expression in the survival of astrocytoma patients

The PC10, a monoclonal antibody against proliferating cell nuclear antigen (PCNA), is known to show immunoreactivity in routinely processed paraffin embedded tissue. This antibody was applied to 72 astrocytic tumours from surgical biopsy material obtained in a ten year period. The PCNA labelling index (LI) obtained by image analysis was compared with patient's survival, age at diagnosis, and Karnofsky score as well as the histological grade of tumour. The survival analysis shows that patients with tumour PCNA LI of more than 6% have significantly poorer prognosis than those with 6% and below. In addition, there is also good correlation between PCNA LI with age, Karnofsky and tumour grade. This study suggests that although the PCNA expression of astrocytoma could be a useful predictor of patient's outcome, it is not an independent prognostic factor but has derived its statistical association with survival secondarily through its relationship with tumour grade, age and Karnofsky score.

Unilateral Creutzfeldt-Jakob disease presenting as rapidly progressive aphasia

A 64-year-old man presented with a three day history of progressive Broca's aphasia, followed within 3 weeks by exclusively right-sided myoclonus, rigidity, and dystonia. Within 4 weeks he was globally aphasic. He died within 7 weeks of onset. In the final week, rigidity and myoclonus became bilateral. CT and MRI were normal. SPECT showed diminished perfusion of the left hemisphere. EEG showed periodic discharges on the left. At autopsy, there were marked cortical spongiform change, neuronal loss, and gliosis throughout the left hemisphere and in the right occipital cortex. Elsewhere in the right hemisphere, spongiform change was non-existent to minimal. There was moderate spongiform change in the molecular layer of the cerebellar cortex, much more marked on the left. Clinical and pathological unilateral cerebral predominance extended to the ipsilateral cerebellum. Creutzfeldt-Jakob disease is an important consideration in patients with rapidly progressive unilateral cerebral signs associated with a movement disorder.

Increase in enkephalin-like immunoreactivity in hippocampi of adults with generalized epilepsy

The changes of opioid peptide reactivity in seizure activity have been well studied in animals. Increased enkephalin and dynorphin immunoreactivity in the hippocampi of animals are interpreted as the result of seizure induced mossy fibre sprouting. We studied the hippocampi of six patients with a history of long-standing grand mal seizures and six age-matched control patients with no history of epilepsy or neurologic disease, using frozen sections which were immunostained with antibodies against Leu-enkephalin and Met-enkephalin. The staining intensity in the CA3, CA4 and internal molecular layer of the dentate fascia in each case was quantified using optical densitometry image analysis. The CA3 and CA4 of the epileptic hippocampi showed highly significant increase in Leu-enkephalin-like immunoreactivity compared to the controls (P < 0.005) while the inner molecular layer showed only significant increase (P < 0.05). Met-Enkephalin-like immunoreactivity was only significantly increased in CA4 of the epileptic hippocampi (P < 0.05).

Regional brain activity of free radical defense enzymes in autopsy samples from patients with Alzheimer's disease and from nondemented controls

Several lines of evidence support the hypothesis that oxygen free radicals are involved in the destruction of neurons in various degenerative disorders of the central nervous system. The activities of superoxide dismutase, catalase and glutathione peroxidase, three enzymes that contribute to the cellular defenses against free radical damage, were measured in different areas of autopsy brains from patients with Alzheimer's disease and from age matched controls. All brains were removed within 24 hours of the time of death and were cut in half sagitally. One half was stored frozen at -86 degrees C and the other half was examined histologically to confirm the presence or absence of Alzheimer's disease. Samples were taken from the frozen half for the enzyme assays. In control brains, the activity of superoxide dismutase is significantly higher in the cerebellum, frontal cortex and hippocampus than it is in the temporal cortex, parietal cortex and entorhinal cortex. The activity of catalase is significantly higher in cerebellum and frontal cortex than in hippocampus, parietal cortex and entorhinal cortex. Glutathione peroxidase activity is uniform across all brain areas studied. In Alzheimer's brains, superoxide dismutase activity is not statistically different among the various brain regions studied, but it is significantly lower than control in the cerebellum (-27%), frontal cortex (-27%) and hippocampus (-35%). Catalase is significantly higher in Alzheimer's cerebellum, frontal cortex and temporal cortex than in Alzheimer's hippocampus, parietal cortex and entorhinal cortex. However, there are no significant differences in catalase activity between Alzheimer's and control samples.(ABSTRACT TRUNCATED AT 250 WORDS)

Neuronal intranuclear hyaline inclusion disease with progressive cerebellar ataxia

Neuronal intranuclear hyaline inclusion disease is a progressive, fatal neurologic condition characterized by eosinophilic inclusions in neurons of the central, autonomic, and peripheral nervous systems. The clinical and pathologic findings of a 4-year-old boy who presented with a rapidly progressive cerebellar ataxia and seizure disorder that had begun 2 years earlier are described. Although intraneuronal inclusions were identified in neurons of cortex, basal ganglia, brainstem, cerebellum, and spinal cord, clinical signs were restricted to cerebellar ataxia, internuclear ophthalmoplegia, and cognitive delay. Predominant cerebellar atrophy, early age of onset, and short clinical course distinguishes it from previously reported patients.

Glioblastoma multiforme presenting with recurrent neurological deficits: Transient ischemic attacks or tumor attacks

Transient ischemic attacks result from the temporary focal interruption of blood flow to the brain. We present three patients with glioblastoma multiforme and recurrent speech arrests or right-sided numbness. The clinical diagnosis of "transient ischemic attack" was made in each patient. This diagnosis remained unchanged for months to 2 years after initial presentation and investigations. The correct diagnosis was made with a brain biopsy in two patients and as a result of additional investigations in the third patient. It is important to remember brain tumor in the differential diagnosis of patients presenting with recurrent brief neurological symptoms.

Aluminum pretreatment impairs the ability of astrocytes to protect neurons from glutamate mediated toxicity

A number of laboratories have shown that astrocytes protect neurons from glutamate excitotoxicity. The experiments described in this paper were designed to address the question whether prior exposure of astrocytes to aluminum (in the form of aluminum citrate) interfered with the ability of astrocytes to protect neurons from glutamate excitotoxicity. Our culture paradigm consisted of highly enriched cultures of neurons and astrocytes grown on separate coverslips; this design enables one to subject either the neurons or the astrocytes to specific treatments and recombine the cells into the same petri dish simply by moving coverslips from dish to dish. We have confirmed findings of other laboratories that astrocytes could protect neurons from glutamate-induced death when glutamate (100 microM) is added to the culture medium. We have also demonstrated that prior treatment of astrocytes with 100 microM aluminum citrate impairs this ability of astrocytes to promote neuronal survival. No differences, however, were observed in the ability of control and aluminum-treated astrocytes to take up glutamate. These findings suggest that aluminum may cause astrocytes to: (i) secrete a factor that makes neurons more susceptible to glutamate-induced toxicity; (ii) secrete a neuronotoxic factor in the presence of glutamate; or (iii) reduce secretion of a factor that protects neurons from glutamate excitotoxicity.

Neurite promoting activity of insulin, insulin-like growth factor I and nerve growth factor on spinal motoneurons is astrocyte dependent

Mouse motoneurons were isolated from dissociated E15 mouse spinal cord and grown on polyornithine-coated round coverslips in a growth medium (DMEM/F12) supplemented with progesterone, trans-ferrin, selenium, horse serum and muscle extract. Astrocytes from newborn mouse neopallium were grown on rectangular coverslips. The motoneuron neurite growth was determined at day 8 of culture by counting, using the light microscope, the intersections produced by neurites radiating from the perikaryon placed centrally in a graticule eyepiece of concentric circles. The mean intersections for cultures without addition of astrocytes, insulin, insulin-like growth factor I (IGF-I) or nerve growth factor (NGF) was 12.6 +/- 0.8. When astrocytes on a separate coverslip were introduced from day 1, there was a small increase in neurite growth (16.3 +/- 0.9). The neurite growth was further increased significantly with the addition of insulin (27.3 +/- 1.4), IGF-I (31.5 +/- 1.4) or NGF (21.8 +/- 1.1) to cultures with astrocytes. Insulin, IGF-I or NGF in the absence of astrocytes did not greatly increase the neurite growth. We conclude that insulin, IGF-I and NGF promote neurite growth through some interactions with astrocytes.

Epilepsy and bathtub drowning. Important neuropathological observations

Drowning is a well-recognized cause of death in persons with epilepsy. Investigation of bathtub drowning is often not straightforward. We report three cases of bathtub water drowning of patients with neuropathological bases for seizures. The importance of neuropathological examination is discussed. A high index of suspicion is required for all cases of bathtub-related death, even in the absence of history of previous seizure disorders. Neuropathological examination must be performed to look for anatomical lesions associated with seizures. Identification of these findings could be very helpful in ruling out homicide or suicide as the cause of death in bathtub drownings.