David J. Gower

The role of MR imaging in the diagnosis and treatment of anterior sacral meningocele (report of two cases)

Anterior sacral meningoceles are rare. This report describes familial anterior sacral meningoceles in a father and daughter who underwent magnetic resonance imaging as part of the preoperative evaluation. Magnetic resonance imaging showed a pelvic teratoma in the daughter and confirmed the absence of abnormal tissue in the father--findings not clearly provided by ultrasound studies, myelography, or contrast-enhanced computerized tomography. It is believed that MR imaging is the most useful preoperative diagnostic technique available in establishing a treatment plan for anterior sacral meningocele.

Diastematomyelia: a 40-year experience

Diastematomyelia is a rare but potentially devastating spinal dysraphism classically characterized as a bony or fibrous spur separating two hemispinal cords. This study reviews our experience with diastematomyelia over a 40-year period from 1947 through 1987, and suggests that the neurologic and orthopedic deficits of diastematomyelia remain stable during extended follow-up after surgery.

Surgical repair of aneurysms of the posterior inferior cerebellar artery—A clinical series☆

Aneurysms of the posterior inferior cerebellar artery are relatively rare. Fourteen such aneurysms (10 vertebral, 4 peripheral) are reported, and their clinical presentation, surgical therapy, and outcome are discussed. All 14 patients had suffered a subarachnoid hemorrhage; 93% (n = 13) underwent direct clipping of the aneurysm while 7% (n = 1) underwent coating of the aneurysm. Two patients died in the perioperative period (one from vasospasm and one from rebleeding). Full activity was achieved by all but one (92%) of the remaining patients in extended follow-up.

Aneurysm of the superficial temporal artery.

A young patient with the posttraumatic development of a superficial temporal artery (STA) aneurysm is described. The STA was ligated proximal and distal to the aneurysm, and the aneurysm was removed. The diagnosis and treatment of traumatic STA aneurysms are discussed.

Subgaleal Hematoma in a Child, without Skull Fracture

The rare cases of subgaleal hematoma in childhood reported previously have all been related to head trauma. A case of apparently spontaneous subgaleal hematoma is reported which was associated with a qualitative platelet defect and not with trauma. Subgaleal hematoma must be differentiated from subgaleal infection and air from frontal sinusitis with bony erosion, and from an encephalocele or tumor erosion through the skull. Computed cranial tomography is useful in that differentiation. Most cases have been managed conservatively, but subgaleal tap may be indicated if there is severe headache or potential scalp necrosis.

Axonal transport of clathrin-associated proteins.

Clathrin, the main constituent of coated vesicles, is anterogradely transported exclusively in the slow component b (SCb) of axonal transport. However, it has not been shown whether the 30-36-kDa clathrin-associated proteins (CAPs), which may regulate assembly of clathrin into coated vesicles, are transported along with clathrin in SCb. Clarification of this point has implications for the functional state of anterogradely transported clathrin. To investigate CAPs transport, retinal ganglion cells of the guinea pig were labeled with 35S-methionine and the optic nerves harvested at 6 h, 4 days, and 30 days to collect radiolabeled proteins from each major rate component of axonal fast component (FC), slow component a (SCa), and SCb. The radiolabeled rate component proteins were analyzed by using two-dimensional polyacrylamide gel electrophoresis and fluorography. The results showed that CAPs, like clathrin, were transported exclusively with the proteins of SCb. In addition, a comparison of radiolabeled CAPs isolated from axons with whole-brain CAPs failed to demonstrate an appreciable difference in molecular weight or isoelectric point between the two, suggesting that CAPs did not undergo a major post translational modification upon passage into the synaptic terminal. It appears that the distinctive microenvironment within the synaptic terminal is likely to contribute to the ability of clathrin and CAPs to interact with membranes.

Candida albicans Shunt Infection: Report of Two Cases

Infection of cerebrospinal fluid shunts with Candida albicans is reported in two patients. Scanning electron microscopy in one case demonstrates the relationship of the Candida hyphae to the white blood cells and to silicone plastic. A review of 10 previously reported cases of Candida shunt infection indicates that the infection usually follows a major bacterial infection or direct contamination or occurs spontaneously. Previous therapy has usually involved removal of the shunt, and the role of parenteral antifungal therapy is still unclear. Overall mortality to date is 25%.

Thoracic intraspinal lipoma: Short Report

Intraspinal lipomas are rare congenital tumours that most commonly occur at the conus. We describe a thoracic intraspinal lipoma presenting with a myelopathy and imaged by MRI. Surgical decompression and dural enlargement appears to be the treatment of choice in those patients who develop spinal cord dysfunction associated with an intraspinal lipoma.

Protein modification by RNA-dependent posttranslational aminoacylation in synaptoplasm

Abstract: A soluble enzyme system that posttranslationally adds [3H]arginine to proteins in a ribosome‐free preparation of guinea pig synaptoplasm is described. The reaction in synaptoplasm is inhibited by the addition of ribonuclease‐A and puromycin, indicating tRNA dependence. A limited number of proteins in synaptoplasm (molecular weights of 20, 37, and 50 kilodaltons) were found to accept arginine. We suggest that RNA‐dependent postranslational amino acylation is used by the mammalian neuron for protein processing at the synaptic terminal.