Natural and lesion-induced apoptosis in the rat striatum during development.

We evaluated the pattern of apoptosis in the rat striatum during normal development and in two models of lesion-induced cell death. Lesions included i) unilateral ablations of the cerebral cortex at different postnatal ages, and ii) early postnatal lesions of the catecholaminergic afferent systems of the striatum with 6-hydroxydopamine (6-OHDA). Dying cells were identified as apoptotic using the TUNEL (terminal deoxynucleotidyl-transferase-mediated dUTP-biotin nick end labeling) method at the light and electron microscopic levels. Moreover, we used immunohistochemistry for the apoptotic markers active caspase-3 and fractin. TUNEL+ cells were present in the striatum during the first four postnatal weeks. Their frequency was high during the first postnatal week and peaked at postnatal day (P)5. Cortical lesions at birth, in contrast to those performed at later stages, induced a significant increase in the frequency of TUNEL+ cells in the ipsilateral striatum, which peaked at seven days postlesion. 6-OHDA lesions resulted in a similar and significant increase in the frequency of TUNEL+ cells in the striatum, which also peaked at P7. We also showed that cortical lesions at P0 and 6-OHDA lesions resulted in a reduction in the frequency, as well as in alterations of the morphology of gamma-aminobutyric acid (GABA)-immunoreactive (ir) neurons in the striatum. We suggest that: i) apoptosis in the striatum is temporally coordinated with maturation events in this area and ii) early developmental lesions of major afferent pathways to the striatum affect both the survival and phenotype of striatal neurons.

[Treatment of complicated fracture of the distal radius with external fixator. Follow-up--complications--outcomes]. / Behandlung der komplizierten distalen Radiusfraktur mit dem Fixateur externe. Verläufe--Komplikationen--Ergebnisse.

The performance of the external fixation regarding severe fractures of the distal radius was evaluated by means of a very detailed retrospective study. Between 1989 and 1994 74 Patients with 76 fractures of the distal radius with a mean age of 69 years for female and 39 years for male patients were treated with the external fixator. 37% were open fractures. Using the ASIF classification, 21% were type A-fractures, 8% were type B-fractures and 71% were type C-fractures. In 44 cases the external fixator was used primarily, in 32 cases secondarily after failed conservative treatment. Additional procedures were partially necessary (K-wires, screws, bone grafts etc.). 32 complications had to be noted, the lesion of the superficial branch of the radial nerve being the most common (16%). After a mean follow up of 36 months 60 patients with 61 fractures could be evaluated clinically and radiologically. With the Sarmiento score as well as the Castaing score, 84% could be classified as very good or good, 16% as fair, no poor results were recorded. From this study we conclude that the primary treatment of complex fractures of the distal radius can be performed with external fixation along with the additional procedures necessary (K-wires etc.). Because of the reliable elimination of pain caused by the fracture, it forms a preventive measure against reflex sympathic dystrophy.