mCCDcl1 cells show plasticity consistent with the ability to transition between principal and intercalated cells.

The cortical collecting duct of the mammalian kidney plays a critical role in the regulation of body volume, sodium pH, and osmolarity and is composed of two distinct cells types, principal cells and intercalated cells. Each cell type is detectable in the kidney by the localization of specific transport proteins such as aquaporin 2 (Aqp2) and epithelial sodium channel (ENaC) in principal cells and V-ATPase B1 and connexin 30 (Cx30) in intercalated cells. mCCDcl1 cells have been widely used as a mouse principal cell line on the basis of their physiological characteristics. In this study, the mCCDcl1 parental cell line and three sublines cloned from isolated single cells (Ed1, Ed2, and Ed3) were grown on filters to assess their transepithelial resistance, transepithelial voltage, equivalent short circuit current and expression of the cell-specific markers Aqp2, ENaC, V-ATPaseB1, and Cx30. The parental mCCDcl1 cell line presented amiloride-sensitive electrogenic sodium transport indicative of principal cell function; however, immunocytochemistry and RT-PCR showed that some cells expressed the intercalated cell-specific markers V-ATPase B1 and Cx30, including a subset of cells also positive for Aqp2 and ENaC. The three subclonal lines contained cells that were positive for both intercalated and principal cell-specific markers. The vertical transmission of both principal and intercalated cell characteristics via single cell cloning reveals the plasticity of mCCDcl1 cells and a direct lineage relationship between these two physiologically important cell types and is consistent with mCCDcl1 cells being precursor cells.

Difficulty of perceptual spatiotemporal integration modulates the neural activity of left inferior parietal cortex.

The integration of spatial and temporal information is a prerequisite for skilled movements. Likewise, spatial and temporal information must be integrated to predict the potential collision (or otherwise) of two moving objects. In a previous blocked functional magnetic resonance imaging (fMRI) study [Neuroimage 20 (2003) S82] we showed that collision judgments (relative to size judgments) provoked a significant increase in neural activity in the left inferior parietal cortex (supramarginal gyrus). This result suggests that this region is involved in the integration of perceptual spatiotemporal information in addition to its known involvement in programming skilled actions. To further investigate the impact of the integration of temporal and spatial information on the left parietal cortex we conducted an event-related fMRI study in which we varied the difficulty of the collision (and the size) judgment tasks parametrically. Reaction times and error rates were used as behavioral measures of increasing task demands. There was a significant linear increase in reaction times and error rates during the collision and the size tasks over the four levels of task difficulty. A linear increase of the blood oxygen level-dependent signal in the left inferior parietal cortex was found only for the collision, not for the size, conditions. Neural activation in the left inferior parietal cortex thus paralleled the increasing demands on spatiotemporal integration. This result confirms that the left supramarginal gyrus integrates spatial and temporal information irrespective of motor demands.

[Diagnosis of an initial infratentorial central nervous system B-cell lymphoma during prolonged cortisone medication]. / Diagnose eines initial infratentoriellen primären B-Zell-Lymphoms des ZNS unter prolongierter Kortisonmedikation.

We present a patient with primary central nervous system B-cell lymphoma. He had suffered from slowly developing weight loss and presented to us with disorientation, seizures, and a supranuclear gaze disturbance. The patient was dismissed with the primary diagnosis of autoimmune encephalitis of the brainstem and put on oral corticosteroids. Four months later, his health status had deteriorated, and at that time diagnostic methods pointed to a cerebral lymphoma. Stereotactic biopsy with subsequent immunohistochemistry and polymerase chain reaction analysis revealed a highly malignant B-cell lymphoma of the CNS, despite prolonged corticosteroid treatment. The patient was treated with whole brain radiotherapy.

[High-dose thiopental infusion in cerebral dysfunction following extracorporeal circulation]. / Hochdosierte Thiopentalinfusion bei zerebraler Dysfunktion nach extrakorporalem Kreislauf.

Thiopentone (thp) infusion was administered to 33 patients with cerebral dysfunction or convulsions out of 2986 patients operated on via extracorporeal circulation because of valvular disease, coronary insufficiency, septum defects and intrathoracic aortic aneurysms. If phenytoin, diazepam and clonazepam proved ineffective, thp 10-15 mg/kg was injected slowly, followed by infusion of 2-4 mg/kg/h for 0.5-5 days. 9 patients died. 18 survivors had a good recovery, 6 were moderately disabled. In the survivors embolisation of particulate matter prevailed as a cause of cerebral dysfunction while in nonsurvivors prolonged pre- and postoperative hypotension was the main cause, with one patient suffering a hemispheric infarction. The amelioration of convulsions and psychosyndromes in the survivors is compatible with the known anticonvulsive effect of thp and its alleged influence on cerebral focal ischaemia. However, in protracted cerebral hypoperfusion as a cause of cerebral dysfunction no protection can be expected from thp. The known effects of barbiturates do not justify the use of these substances for the purpose of cerebral protection.