Synthesis and in vitro Trichomonacidal activities of some new dialkylperoxides and 1,2,4-trioxanes.

Two series of three trioxanes and 18 disubstituted peroxides were synthesised and evaluated for their in vitro trichomonacidal activity against Trichomonas vaginalis. The most active compound, 2-methylprop-2-yl 2-methoxyeth-1-yl peroxide exhibited an IC(50) value of 1.0+/-0.2 microM whereas other dialkyl peroxides had various IC(50) values which could not be correlated to their molecule structure. The best compound was about five times more active than metronidazole. The amount of generated oxygen or free radicals cannot explain completely the activity suggesting another way of action for these compounds on T. vaginalis.

[The Ross procedure in the acute phase of infectious endocarditis in childhood]. / Intervention de Ross à la phase aiguë de l'endocardite infectieuse de l'enfant.

The Ross procedure of aortic valve replacement with a pulmonary autograft has several advantages in childhood over mechanical prostheses or homografts, especially in infectious endocarditis requiring early surgery. Between January 1997 and July 1998, 3 children with no known previous cardiac disease, aged 14 months, 10 and 11 years, had aortic valve infectious endocarditis. The causal organism was not identified in 1 case and the other two were due to staphylococcus aureus and corynebacterium diphteriae. All children had severe, rapidly progressive aortic regurgitation complicated by pulmonary oedema in the baby and systemic emboli in the two older children. Surgery was performed within 9 days, 1.5 month and 2 months after the onset of the disease. The postoperative course was uncomplicated in the 3 cases. Postoperative Doppler echocardiography showed absence of autograft dysfunction or stenosis, with the presence of pulmonary regurgitation in 1 case. Pulmonary autograft has the advantages of not requiring anticoagulation, of allowing growth of the aortic ring, of not being limited by the age of the patient and of having a low risk of degeneration and infectious endocarditis. Therefore, it seems particularly indicated for cases of complicated infectious endocarditis requiring early aortic valve replacement. The early (4.8%) and late (4.3%) mortality rates were comparable to those of other techniques and are lower than those associated with valve replacement with mechanical prostheses in cases of endocarditis (8.5% versus 40%). The secondary morbidity is 18.8% with dysfunction of the autograft and/or stenosis of the pulmonary homograft. Despite a limited follow-up, aortic valve replacement by a pulmonary homograft seems better than aortic valve replacement with a homograft or mechanical prosthesis, especially in cases of complicated infectious endocarditis requiring surgery in the acute phase. Further studies are required to confirm these encouraging results.

A drug interaction study between ticlopidine and cyclosporin in heart transplant recipients.

OBJECTIVES: Previous uncontrolled studies have suggested an interaction between ticlopidine, a major antiplatelet agent, and cyclosporin in heart- and kidney-transplant recipients. The aims of this study were to examine in a randomised, double-blind fashion, the possible interaction between cyclosporin A and ticlopidine (250 mg per day) and the tolerability of this combination in heart-transplant recipients. METHODS: Twenty heart-transplant recipients were randomised into either a treated or a placebo group. Blood samples were drawn for time-course evaluation of cyclosporin blood levels over a period of 12 h, following the morning intake of cyclosporin and, for platelet aggregation studies, before and after 14 days of ticlopidine administration. Twenty four-hour urine samples were collected for 6-beta-hydroxycortisol measurements, before and after 14 days of ticlopidine. RESULTS: Although given at half the recommended daily dosage, ticlopidine significantly reduced platelet aggregation. Pharmacokinetic parameters indicate that the bioavailability of cyclosporin A was not significantly modified by ticlopidine. However, one patient in the ticlopidine group was withdrawn because of a major fall in cyclosporin blood level within 3 days of treatment. Urinary excretion of 6-beta-hydroxycortisol was augmented after treatment in the ticlopidine group compared with the placebo group, suggesting that induction of drug metabolism might have occurred. Data also show quite a large intra-individual variability in cyclosporin bioavailability in the placebo group, suggesting that poor absorption of the drug formulation and/or poor compliance might have contributed to the decreased cyclosporin blood levels in the patient withdrawn from this study and in previous uncontrolled studies. CONCLUSION: Cyclosporin bioavailability was not clearly modified by a half dosage of ticlopidine in this study. We, however, recommend closely monitoring cyclosporin blood levels when prescribing ticlopidine. Further studies will be needed with new formulations of cyclosporin or when using the full dosage of ticlopidine.

[Role of echocardiography in the diagnosis of congenital abnormalities of the thoracic aorta]. / Place de l'échocardiographie dans le diagnostic des anomalies congénitales de l'aorte thoracique.

Echocardiography has revolutionized the diagnosis and follow-up of congenital heart disease over the last 20 years. Permanent technological innovation in the field of ultrasonic investigation and in the limitations inherent to this technique are illustrated in the assessment of congenital disease of the aorta, the subject of this review. The role of echocardiography associated with Doppler techniques in the investigation of congenital disease of the aorta varies with age: there is no rival technique in investigation of the foetus; in neonates, infants and young children, the role of ultrasound is preponderant because of the excellent echogenicity and the high incidence of congenital aortic disease occurring in a clinical context of cardiorespiratory distress. The limitations and insufficiencies of the techniques are greater in adolescents and adults in whom other non-invasive techniques are possible in acceptable practical conditions. The reality of progress in diagnosis is demonstrated by the possibility of therapeutic indications based only on the association of clinical and echocardiographic data without need for diagnostic catheterization and angiography. The limitations of ultrasonic techniques should however be recognized to avoid inappropriate usage.