One-stage key pinch and release with thumb carpal-metacarpal fusion in tetraplegia.

One-stage key pinch and release with carpal-metacarpal fusion, extensor pollicis longus tenodesis, and motor transfer to flexor pollicis longus were analyzed for functional results in tetraplegic patients. Eighteen patients (21 hands)--all with International Classification OCu:4 hand function or worse--were studied. Average follow-up was 42 months. All patients experienced significant increase in functional ability and thought the surgery was highly beneficial. Average pinch strength was 3.3 kg, whereas it had been nonmeasurable preoperatively. Both activities of daily living and pinch strength correlated with tetraplegic functional level. The patients with higher preoperative functional level had better postoperative activities of daily living scores and pinch strength. Sixteen hands had solid fusions, and patients with fibrous nonunions showed no decrease in pinch strength, pain, or functional limitations when compared with the patients who had solid fusions. Six hands showed degenerative changes at one or more adjacent joints, but this was not related to results.

The polypeptide PEP-19 is a marker for Purkinje neurons in cerebellar cortex and cartwheel neurons in the dorsal cochlear nucleus.

This light and electron microscopic immunocytochemical study shows that the polypeptide PEP-19, a presumptive calcium binding protein specific to the nervous system, represents an excellent marker for cerebellar Purkinje cells and dorsal cochlear nucleus (DCoN) cartwheel cells. The polypeptide clearly reveals the entire populations of both types of neurons, including their complete dendritic and axonal arborizations. Other PEP-19 containing neurons in the two regions display weak immunoreactivity restricted to the cell body or to cell body and principal dendrites. Electron microscopic localization of PEP-19-like immunoreactivity reveals similarities between this polypeptide, parvalbumin, and a 28K vitamin D-dependent calcium binding protein. However, calmodulin, which is expressed in both Purkinje and granule cells, may differ from PEP-19. Similarities between the organization of the cerebellar cortex and the DCoN superficial layers have been known for some time, with several types of neurons in one system having their presumed homologue in the other. These data provide further support for the proposed structural and functional homology between Purkinje and cartwheel neurons, and establishes PEP-19 as a useful marker for examining degeneration of these two neuronal populations in murine cerebellar mutants.

Central GABAergic innervation of neurointermediate pituitary lobe: biochemical and immunocytochemical study in the rat.

Activity of glutamic acid decarboxylase GluDCase, the biosynthetic enzyme of gamma-aminobutyric acid (GABA) was measured in low-speed homogenate supernatant of the neural and intermediate (neurointermediate) lobe (28--30 pmol of CO2 per microgram of protein per hr) and of the anterior lobe (2--4 pmol of CO2 per microgram of protein per hr). In the neurointermediate lobe, stalk transection reduced the GluDCase activity by more than 95%. By using an antiserum to rat brain GluDCase and the unlabeled antibody--peroxidase method of Sternberger, GluDCase immunoreactivity was localized in many terminals within the neurointermediate lobe of the hypophysis. In pars intermedia, immunoreactive terminals occurred in apposition to secretory cells and to glial cells and were near nonimmunoreactive axonal profiles; in pars neuralis they were apposed to pituicytes and to unlabeled axons including the neurosecretory terminals and were along fenestrated portal capillaries. GluDCase immunoreactive axons terminals exhibited diverse morphological features and would not have been identified as a distinct population without the GluDCase antiserum. No GluDCase-immunoreactivity was found in the anterior pituitary lobe. Stalk transection abolished GluDCase immunoreactivity in the neurointermediate lobe. These data provide biochemical and morphological evidence for a central GABAergic innervation of neural and intermediate lobes of the hypophysis.