Astrocytic contribution of endothelial cell monolayer permeability was examined in two blood-brain barrier (BBB) models, using the coculture in a double chamber system: rat astrocytes and bovine aortic endothelial cells (BAECs) or bovine brain endothelial cells (BBECs). In system 1, where astrocytes were separated from endothelial cells, a 40% reduction in L-glucose permeability of the BBEC monolayer, but not the BAEC monolayer, was observed by cocultivation with astrocytes. Although several passages of BBEC in culture elicited morphological transformation from spindle-shapes to cobblestone-like features, the passaged BBECs remained responsive to astrocytes in coculture in system 1 (37% reduction of the L-glucose permeability). By contrast, in system 2, where respective endothelial cells and astrocytes layered on the upper and lower surfaces of a membrane, the permeability of both BAEC and BBEC monolayers was reduced by cocultivation with astrocytes (75% reduction for BAEC and 40% reduction for BBEC). BAECs in this contiguous coculture (system 2) with astrocytes showed numerous tight junction-like structures characteristic of the BBB in vivo. These results suggest that primary cultured BBECs, which had been primed by astrocytes in vivo, retain a higher sensitivity to astrocytes possibly through an astrocytic soluble factor (s) to exhibit BBB-specific phenotypes, and that even BAEC from extra-neural tissues, when cultured with astrocytes in close proximity in vitro, may acquire the similar phenotypes and serve for an extensive use of BBB model in vitro.

Animals↗

PubMedDate not supplied

Focal meningoencephalitis localized in the left occipital lobe.

A rare case of suspected focal meningoencephalitis localized in the left occipital lobe was described. A 2-year-old girl, following upper respiratory illness, suddenly became lethargic and experienced a right-sided hemiconvulsion beginning from a right-side gaze. Cranial MRI clearly demonstrated high intensity on T2-weighted imaging in the cortex, white matter, and leptomeninges of the left occipital lobe, which disappeared in the convalescent phase. We consider that the MRI abnormalities reflected focal inflammation and edema, and corresponded to the presumed ictal focus.

Brain Edema↗

PubMedDate not supplied

Reverse gyrase--a topoisomerase which introduces positive superhelical turns into DNA.

An enzymatic activity which converts closed circular DNA into a positively supercoiled form is present in cellular extracts of Sulfolobus, an acidothermophilic archaebacterium. This novel enzyme is a type II DNA topoisomerase and is active only at temperatures greater than 55 degrees C, in the presence of ATP and Mg2+.

DNA Topoisomerases, Type I↗

PubMedDate not supplied

Epileptiform EEG discharges in healthy children: prevalence, emotional and behavioral correlates, and genetic influences.

Epileptiform discharges in 8 electrode waking EEGs at rest and during hyperventilation in 1,057 healthy children aged 6-12 years from an elementary school were studied: Epileptiform discharges, detected in 53 children (5.0%), consisted of centrotemporal spikes (37 cases), generalized spike and slow wave complexes (10 cases), occipital spikes (2 cases), frontal spikes (1 case), and a combination of multiple spike and slow wave complexes and focal spikes (2 cases). The occurrence of a positive past history of febrile convulsions was higher in children with epileptiform discharges (18.9%) than in those without epileptiform discharges (9.4%). Using the Rutter scales for teachers and parents, we compared the emotional and behavioral problems of children with epileptiform EEG discharges with those of children without epileptiform discharges. No statistically significant differences were noted, indicating that the emotional and behavioral problems existing are most probably coincidental and not directly related to the epileptiform discharges. A genetic basis for generalized epileptiform discharges was postulated because the occurrence of generalized discharges in siblings of probands with generalized discharges was higher (4 of 9, 44.4%) than the prevalence in all subjects. However, the occurrence of centrotemporal spikes in the siblings of probands with centrotemporal spikes was not higher (2/38, 5.3%) and an autosomal-dominant genetic factor for centrotemporal spikes in waking EEGs of healthy children could not be confirmed.

Affective Symptoms↗