Effect of flosequinan on ischaemia-induced arrhythmias and on ventricular cyclic nucleotide content in the anaesthetized rat

1. Flosequinan, milrinone, isoprenaline and forskolin given intravenously at similarly hypotensive doses have been evaluated in separate studies for their effect on ischaemia-induced arrhythmias and on ventricular cyclic nucleotide content following coronary artery ligation in the pentobarbitone anaesthetized rat. 2. Flosequinan did not affect mortality or arrhythmias following coronary artery ligation in either study and no change in ventricular cyclic nucleotide content was observed. 3. Isoprenaline caused a significant increase in mortality (P < 0.05) in both studies whereas milrinone and forskolin caused a significant increase in mortality in only one of the two studies conducted. All three agents caused significant increases in cyclic AMP which were associated with increased incidence of arrhythmias. 4. When compared at similarly hypotensive doses, flosequinan, in contrast to milrinone, isoprenaline and forskolin, did not influence ischaemia-induced arrhythmias or raise ventricular cyclic nucleotide levels in the anesthetized rat.     

Traumatic pseudoaneurysm of the superficial temporal artery

This paper describes, by case histories and a literature review, the cause, diagnosis and therapy of pseudoaneurysm of the superficial temporal artery. Two patients with a traumatic pseudoaneurysm of the superficial temporal artery were examined by physical examination and histology of the excised lesions. Blunt injury caused a histologically proved pseudoaneurysm in two reported cases. A total of 12 additional reports of pseudoaneurysm of the superficial temporal artery were found in the literature. Pseudoaneurysm of the superficial temporal artery is an uncommon complication of blunt head injury. Symptoms are limited and diagnosis can be made by noninvasive means. A high suspicion level for arterial injury and sufficient follow-up of patients is necessary for the detection of arterial injury.     

Transplanted oligodendrocyte progenitor cells expressing a dominant-negative FGF receptor transgene fail to migrate in vivo

The proliferation, migration, survival, and differentiation of oligodendrocyte progenitor cells, precursors to myelin-forming oligodendrocytes in the CNS, are controlled by a number of polypeptide growth factors in vitro. The requirement and roles for individual factors in vivo, however, are primarily unknown. We have used a cell transplantation approach to examine the role of fibroblast growth factor (FGF) in oligodendrocyte development in vivo. A dominant-negative version of the FGF receptor-1 transgene was introduced into oligodendrocyte progenitors in vitro, generating cells that were nonresponsive to FGF but responsive to other mitogens. When transplanted into the brains of neonatal rats, mutant cells were unable to migrate and remained within the ventricles. These results suggest a role for FGF signaling in establishing a motile phenotype for oligodendrocyte progenitor cell migration in vivo and illustrate the utility of a somatic cell mutagenesis approach for the study of gene function during CNS development in vivo.