Review of 387 isolated mitral valve replacements by the Model 6120 Starr-Edwards prosthesis

Between February, 1965, and July, 1980, 387 patients underwent an isolated mitral valve replacement with the non-cloth covered Starr-Edwards ball valve (Model 6120) at the University of Louvain. The mean age of the patients was 48.765 years. The overall operative mortality was 6.1%. The mean age of the patients who died was 52.3 years and all but four were in New York Heart Association (NYHA) Functional Class III or IV. The actuarial survival rate is 78% at 5 years after operation, 72% at 10 years, and 70% at 13 years. The overall incidence of thromboembolic complications is 3.4% per patient-year with a total follow-up of 1,675 patient-years. Valve dysfunction has never occurred, and endocarditis, hemolysis, and paravalvular leakage have never reached a significant incidence. Hemodynamics investigations show a residual diastolic gradient of 6.6 mm Hg for the size 3M valves and 7.92 mm Hg for the size 2M valves. These current data over an extended follow-up interval (15 years) indicate that the Starr-Edwards Model 6120 prosthesis continues to perform satisfactorily in terms of mortality and morbidity, and there have been no instance of late failure due to valve dysfunction.

[Triangular comparison of the agar diffusion method, the ABAC system and the Sensitre system for determination of bacterial sensitivity to aminoglycoside chemoantibiotics]

The in vitro activity of sisomicin, gentamicin, tobramycin and amikacin, four similar aminoglycosides, has been determined against 135 bacterial strains of Gram-negative bacilli representing 4 genera of common pathogens isolated from urinary tract infections. Comparison between three methods of antibiotic susceptibility tests: agar diffusion by Kirby-Bauer, semi-automatic technique using ABAC apparatus (Intertechnique, Sclavo) dilution method (MIC), has shown a considerable percentage of agreement, in almost all cases. The highest percentages of agreement have been shown for sisomicin and tobramycin. The authors analyze the role of the new techniques representing an advance in routine work.

Effect of chloro-N-desmethyldiazepam on serum and brain tryptophan and serotonin in relation to the activity of central serotonergic neurons

Chloro-N-desmethyldiazepam (CDD) significantly reduced plasma tryptophan (TRY) and increased brain TRY in mice and rats. Quipazine did not change TRY levels in mouse plasma and brain but it respectively reduced and increased these two parameters in rats, to almost the same extent as CDD. Metergoline, an antagonist of serotonergic receptors, decreased blood TRY in both mice and rats but failed to change brain TRY. CDD significantly but slightly increased brain serotonin in rats. This effect was blocked by metergoline.

Neurochemical correlates of muricidal behavior in rats

Surgical, pharmacological or environmental manipulation are widely employed to induce muricidal behavior in naive laboratory male rats. The genetic predisposition of an animal strain to kill mice remains, however, an important factor to obtain the muricidal reaction. Data from the pertinent literature suggest that muricidal behavior may possibly be sustained by increased dopaminergic or catecholaminergic activity in the presence of reduced serotoninergic activity. The results here presented indicate, instead, that complete abolition of brain serotoninergic control, i.e., maximal depletion of brain serotonin, is just enough per se to induce muricidal activity. Further, this chemically-induced muricidal activity goes well beyond any pre-existing strain predisposition to kill mice or not.

[Our experience with treatment of aneurysms of the thoracic aorta]

From 1964 to 1977, 64 patients affected by aneurysm of the thoracic aorta were surgically treated at the 2nd Surgical Department of the University of Milan (Head: Prof. E. Malan). 25 patients had a true aneurysm and 34 a dissecting aneurysm. The various surgical techniques are discussed. The mortality rate and postoperative results are presented.

Piracetam activity may differ according to the age of the recipient mouse

Piracetam has bee administered to young and old mice to investigate whether the age may differently modulate the activity of this centrally acting drug. After piracetam administration, old mice showed a notably greater increase of their brain tryptophan than young animals. Furthermore, piracetam significantly improves the learning capacity of young mice, but the drug is remarkably more active in improving the performance by old mice. These facts may then suggest that this compound is especially effective in restoring the neurobiological setting of the aging brain.

[Changes in the plasma magnesium content in patients subjected to cardiopulmonary bypass]

Changes in plasma magnesium content in 17 patients operated in extracorporeal circulation are reported. Values were low at the end of the operation, but rose at the end of the first day to achieve spontaneous resolution of the condition within 3 days. No close relationship between such loss and immediate postoperative arrhythmia could be discerned. Attention is, however, drawn to 3 cases in which ventricular fibrillation was not resolved until electric shock treatment was preceded by the administration of magnesium sulphate.