Magnetic resonance imaging (MRI) was performed postmortem on the brains of 40 patients aged over 60 yrs who had died from causes other than brain disease. Periventricular lesions of increased signal intensity on T2-weighted images, graded as moderate or severe, were found in 10% of the patients in the age group between 60 and 69 yrs, and in 50% between 80 and 89 yrs. Macroscopic and microscopic whole-brain sections were studied in 19 brain specimens (8 with normal white matter, 4 with moderate lesions and 7 with severe lesions of the white matter on MRI). The presence or absence of periventricular lesions on MRI correlated well with the severity of demyelination and astrocytic gliosis. Demyelination was always associated with an increased ratio between wall thickness and external diameter of arterioles (up to 150 microns). A variable degree of axonal loss in Bodian-stained sections was present in the white matter of all brains with demyelination. Dilated perivascular spaces were found and studied morphometrically in 9 brain specimens; their presence correlated strongly with corrected brain weight, but incompletely with demyelination and arteriolosclerosis. Our findings suggest that arteriolosclerosis is the primary factor in the pathogenesis of diffuse white matter lesions in the elderly. This is soon followed by demyelination and loss of axons, and only later by dilatation of perivascular spaces.

Prostaglandins of the E series have been shown to have immunosuppressive properties. To study the effects of the prostaglandin E1 analogue misoprostol on renal function and graft rejection after transplantation, we conducted a randomized, double-blind, placebo-controlled trial in 77 renal-allograft recipients. The subjects received misoprostol (200 micrograms four times daily by mouth; n = 38) or placebo (n = 39) for the first 12 weeks after transplantation, in addition to standard immunosuppression with cyclosporine and prednisone. They were then observed for an additional four weeks after the drug or placebo was discontinued. Treatment with misoprostol was associated with a significant improvement in renal function as judged by the mean (+/- SEM) serum creatinine concentration (128 +/- 7 vs. 158 +/- 11 mumol per liter after 12 weeks; P = 0.03) and creatinine clearance (84 +/- 6 vs. 69 +/- 5 ml per minute per 1.73 m2 of body-surface area; P = 0.05). There was a significant reduction in the incidence of acute rejection in the group treated with misoprostol as compared with the placebo group (10 of 38 vs. 20 of 39; P = 0.02), and there was less need for rehospitalization after transplantation (4 +/- 1 days with misoprostol vs. 10 +/- 2 days for placebo; P = 0.03). Although blood levels of cyclosporine did not differ significantly between the groups, they tended to be higher in the misoprostol group, as did the incidence of acute nephrotoxicity due to cyclosporine (13 of 38 vs. 8 of 39). Infectious complications tended to be fewer in the misoprostol-treated group (14 of 38 vs. 21 of 39). We conclude that misoprostol improves renal function and safely reduces the incidence of acute rejection in renal-transplant recipients treated concurrently with cyclosporine and prednisone.

There is evidence that the Pena-Shokeir syndrome is not a specific phenotype but should be regarded as a "fetal akinesia deformation sequence". A neuropathological study of six random new cases was performed to evaluate this theory. Brain pathology observed included persistent fetal meningeal vascularization (two cases), agenesis of the septum pellucidum (one case) and hydranencephaly (one case). Investigation of the spinal cord (in two cases) revealed no abnormalities. Muscle histology (in four cases) was indicative of neurogenic atrophy in two cases. These findings are compared with the data of the 28 cases previously described. It is concluded that the Pena-Shokeir syndrome is a heterogeneous syndrome in which cerebral lesions may play an important role in the pathogenesis. The cerebral malformations may also indicate the time of origin and contribute in the perinatal death of this syndrome.

We describe a median "cleft" face anomaly (MCFA) with congenital hypothalamic hamartoma in a newborn girl. The MCFA was associated with a frontal midline skull lipoma and a complex congenital heart defect. Possible pathogenetic mechanisms are discussed, and a review of the pertinent literature is given. It is concluded that probably all malformations in our patient are disturbances of a single developmental field defect, ie, the midline.

In primary human brain tumours a shift occurs in the synthesis of isoenzymes of pyruvate kinase from the M towards the K-type. In astrocytomas, oligodendrogliomas and glioblastomas, which were localised in the cerebral hemispheres of adult patients over 20 years of age, the shift correlated well with histological grading and growth rate as observed in postoperative survival. Gliomas of adults, localised in midline structures, as well as childrens gliomas were characterised too by a strong shift from M towards the K type. However, in these tumours, less correlation with histological grading and growth rate was found. The isoenzyme shift can be rapidly demonstrated with an alanine inhibition test. The application of this assay may have a diagnostic value during operation for gliomas in grading of malignancy in adults as well as demarcation of the resection of gliomas in all age groups. The test can be performed within 10-15 min and can thus fit easily into a surgical procedure. A case report is presented for illustration.