Chromosome aberrations in patients irradiated for pelvic tumours

Peripheral blood lymphocytes of patients undergoing radiation therapy for pelvic tumours have been examined for the presence of dicentric and centric ring chromosomes. Blood samples were taken, by venipuncture, prior to the first radiotherapy session and 24 h after radiotherapy sessions to allow the mixing of the irradiated lymphocytes in the circulating blood. The yield of dicentrics and centric rings was best fitted by a straight line which, according the maximum likelihood method, corresponds to Y = 1.77 +/- 0.0003 10(-2) D. On this basis the dose inducing ten dicentrics or rings is 5.62 Gy at the target volume and, thus, is intermediate between the doses at the target volumes displaying the same effects in patients treated for mammary carcinoma (15 Gy) or for ankylosing spondylitis (2 Gy).     

Enoximone and the therapeutic strategy in patients awaiting emergency cardiac graft

Enoximone is a positive inotropic agent belonging to the group of phosphodiesterase F-III inhibitors. The drug was tested in 34 patients uncontrolled by sympathomimetic drugs and referred to our department for urgent heart transplantation or circulatory assistance. After insertion of a Swan-Ganzgatheter and a radial artery catheter for haemodynamic monitoring, enoximone was administered as a 15-minute intravenous bolus injection of 1 to 2.5 mg/kf every 8 hours, in addition to sympathomimetic agents. Clinical and haemodynamic improvement was observed after thirty minutes in 30 patients. The cardiac index rose from 1.82 to 2.67 l/min/m2 and the pulmonary wedge pressure fell from 30.8 to 18.9 mmHg. Systemic arterial resistance decreased from 2170 to 1520 dyn. s. cm-5, and pulmonary resistance from 5.5 to 4.6 Wood units (p less than 0.01 for all values). Four patients had no haemodynamic improvement and were put on circulatory assistance, using a Jarvik 7 total artificial heart in 3 of them and heterotopic circulatory assistance in one. After clinical investigation for contra-indication to heart transplantation, and as their improved haemodynamic status permitted, 12 of the 30 patients were considered suitable (group B) for heart transplantation. Transplantation was performed within a week of admission in 11 patients without any need for mechanical assistance. One of the group B patients who required implantation of a Jarvik 7 artificial heart died after 12 hours of assistance. Eighteen patients were considered unsuitable for transplantation (group A) and treated medically.(ABSTRACT TRUNCATED AT 250 WORDS)     

Evidence of lowest brain penetration of an antiemetic drug, metopimazine, compared to domperidone, metoclopramide and chlorpromazine, using an in vitro model of the blood-brain barrier.

PURPOSE: The objective of the current study was to determine the ability of some antiemetic compounds to cross the blood-brain barrier (BBB) and thereby to determine possible side effects of compounds for the central nervous system (CNS). METHODS: We compared the brain penetration of some antiemetic compounds using an in vitro BBB model consisting in brain capillary endothelial cells co-cultured with primary rat glial cells. RESULTS: This study clearly demonstrated that the metopimazine metabolite, metopimazine acid, has a very low brain penetration, lower than metopimazine and even less than the other antiemetic compounds tested in this study. CONCLUSIONS: The poor brain penetration of metopimazine acid, metopimazine biodisponible form, seems very likely related to the clinically observed difference in therapeutic and safety profile.     

Cancer et environnement: le cas de l’amiante

Asbestos has been used extensively in industrialised countries for more than a century, causing ongoing increases in mortality from mesothelioma. Despite its regulation and ban in France in 1997, and because of the 30-year cancer latency period after exposure to it, mortality from mesothelioma will continue to increase in the country for several decades, peaking between 2020 and 2030. The risk of mesothelioma from asbestos exposure is dose dependent and higher for amphiboles. For lung cancer, the risk increases linearly with cumulative exposure, regardless of the type of asbestos; this risk is similar in the presence or absence of pleural plaques. Smoking acts with asbestos to greatly increase the risk of lung cancer, but the effects of asbestos and smoking are independent. Regarding low-level exposure, an excess of mesothelioma and lung cancer has been observed in the vicinity of mines, asbestos manufacturers and natural geologic sites (para-occupational, domestic and environmental exposure); we have been unable to demonstrate safe levels of asbestos exposure.