Vermectomy enhances parvalbumin expression and improves motor performance in weaver mutant mice: an animal model for cerebellar ataxia.

In the Weaver mutant mouse (wv/wv), an animal model for hereditary cerebellar ataxia, electrophysiological experiments have revealed a disorganized output of cerebellar Purkinje cells (the latter using GABA as an inhibitory transmitter) which, by a cascade of mechanisms, was thought to be the cause of the poor motor abilities. In Purkinje cell degeneration mice (pcd/pcd) lacking nearly all Purkinje cells and displaying milder motor deficiencies than wv, in comparison to wild-type mice, a strong increase in parvalbumin- and (co-localized with parvalbumin) glycine-immunopositive somata in the deep cerebellar and vestibular nuclei has recently been found. It was therefore intriguing to investigate whether motor performance in weaver mutants could be ameliorated by applying cerebellar lesions to eliminate the faulty output and to look for a change in transmitter weighting, indicated by a strong increase in parvalbumin-positive somata in areas (the respective target areas) which were formerly devoid of it. Ten Weaver mutants were subjected to cerebellar lesions. After removal of the vermis a total abolition of tremor, a definite improvement in the balance of affected body parts, an increase in locomotor activity when tested in an open-field matrix, and a strong increase in parvalbumin expression in Weaver mutant deep cerebellar and vestibular nuclei in comparison to wild-types have indeed been found. Increase in motor activity (or explorative behaviour) has been placed in relation to learning mechanisms. The increase in parvalbumin expression and the observed improvement in motor abilities and mechanisms probably related to learning underline the hypothesis that any change in the physiological equilibrium of the brain function by removal of input or output related to an assembly of nerve cells leads to a cascade of changes at the transmitter and neuronal level in near or distant connected brain structures.

Epidural abscess of the cervical spine with osteomyelitis of the odontoid process.

STUDY DESIGN: A case report. OBJECTIVES: To document the rare condition of staphylococcal osteomyelitis of the odontoid process and to increase knowledge about the clinical characteristics and favorable outcome if patients are managed appropriately. SUMMARY OF BACKGROUND DATA: Osteomyelitis of the odontoid process caused by Staphylococcus aureus is a rare disease. A handful of cases have been reported within the last 30 years. Destructive odontoid peg involvement is most commonly associated with rheumatoid disease, which has a distinct clinical course compared with that of bacterial infection. METHODS: Two patients with bacterial osteomyelitis of the odontoid peg underwent medical and surgical treatment. They were observed for 3 years. All authors were involved in the care of these patients. RESULTS: Close monitoring of the patients' neurologic status and the use of noninvasive imaging techniques to evaluate the cervical spine led to an individualized treatment plan including antibiotic medication and transoral surgery with good outcomes in both cases. CONCLUSIONS: Awareness of the occurrence of bacterial osteomyelitis of the odontoid process, with or without neurologic symptoms, in patients with neck pain and fever may lead to earlier detection of this potentially critical condition, which has an excellent prognosis when treated early and appropriately.

Improvement in motor performance of Weaver mutant mice following lesions of the cerebellum.

In Weaver mutants (B6CBA wv/wv) cerebellar granule cells degenerate almost completely postnatally. A partial loss of Purkinje cells (PC) and a degeneration of dopaminergic cells in the substantia nigra have also been found. Weaver mice suffer from striking motor symptoms, including difficulty in walking without toppling over. In an attempt to influence the poor motor performance, the cerebellum in young animals was removed, thus eliminating the faulty output of surviving PCs, demonstrated electrophysiologically. Unoperated Weaver, lesioned wildtypes and one sham mouse were used as controls. Before and after operation, a battery of behavioural tests was performed. In Weaver mice, tumbling to the side (t) and the relation of t to the motor activity (k) while traversing an open-field matrix, (t/k), improved considerably, as did manoeuvring on a slanted wire mesh, but keeping balance on a wooden bench did not to the same degree. Locomotor activity alone improved in some animals. In wildtypes no significant changes occurred after operation, with the exception of a strong reduction in locomotor activity. The experiments demonstrate that the motor performance in Weaver mutant mice benefits from removal of their cerebellum.

[Management strategy in severe craniocerebral trauma in a general surgical department]. / Versorgungsstrategie beim schweren Schädel-Hirn-Trauma in der allgemeinchirurgischen Abteilung.

Emergency treatment of severe head injury combined with multiple trauma in most cases must be performed in regional hospitals and in general surgical units. Especially in acute intracranial hemorrhage (epidural hematoma) with the urgent indication to craniotomy the transmission of the patient in a special neurosurgical department is not possible in an adequate time. Therefore general surgeons should be trained in emergency trepanation of the skull and in basic treatment of severe head injury including measuring of intracranial pressure. The tactics of treatment of severe cranio-cerebral trauma is demonstrated on 46 cases out of 869 patients with head injury treated in our hospital from 1981 to 1984.