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A Bru

Publications and source records attributed to A Bru.

At least 19 recordsLinked to original sources
PubMed1983

[Experimental model for hemodynamic and metabolic studies of extracorporeal circulation. Apropos of 14 cases].

The authors present an homogeneous and stable experimental model, the basic characteristics of which are: 14 extracorporeal bypass with: total bypass; normothermia; total haemodilution; beating heart; continuous flow in dogs anesthetised with chloralose. Three methods were employed: continuous recording of the venous lactate concentration; invasive electromagnetic measurement of the arterial blood flow; measurement of the tissular capillary blood flow with radioactive labelled microspheres. The statistic treatment of the informations gathered confirms that those experimentations took place in normothermia and constant: pH, venous and arterial pressure, cardiac pacing and arterial carotid blood flow. We noticed no modification of the body electrolytic repartition; blood gas variations do not modify haemodynamic conditions. Increase of the lactate concentration, as noticed in the literature, is in relation with a catecholamine hypersecretion and not with an anaerobic tissular function. Tissular capillary blood flow is constant if reported to cardiac index. This model will allow us to compare those results with new series where only one of the basic elements will be modified.

Animals↗
PubMed1979

[Isotopic indicators in the diagnosis of malignant pleurisies (author's transl)].

The tracers that are used in thoracic pathology have an elective tumoural affinity, present such a special reaction towards pleural effusions that we were led to study Bleomycin labelled with Cobalt 57 in 34 cases of pleurisy of various etiologies. The hyperfixation, circumscribed to the effusion in all these cases, presented a double problem : of radiobiological risk and of diagnostic significance. We tried to solve the last problem by means of a precise protocol applied to 16 cases, quantifying comparatively the specific radio-activity of pleural fluid and serum and studying the evolution of the pleural serous gradient, after injection of 2 mCi of labelled Bleomycin in 16 patients with suspected malignant pleurisy. From this limited study, it appeared that the sero-pleural gradient of the tracer, 24 hours after injection, was very high, above 5 and up to 15 in 7 malignant pleurisies out of 8; between 2 and 4 in others. It was sometimes below 5 and less in effusions, non malignant or doubtful. This gradient decreased very rapidly to reach 0 on the fourth day, except in recurring chronic effusions. Pending the confirmation of results, after a prolonged experiment, this protocol appeared valuable for diagnostic and physiopathological reasons.

Adult↗
PubMed1976

[Contribution to the scintigraphic diagnosis of malignant endothoracic tumors by 57Co labeled Bleomycin (author's transl)].

The authors report the results of the exploration by 57Co Bleomycin scinitigraphy in 97 thoracic tumors. The Bleo-57Co scintigraphy detects primary and secondary malignant tumors underevaluated by classical tests. In the thorax, the radioactive focus are easily detected on account of the light physiological fixation of the Bleo-57Co. It is particularly interesting in the mediastinal tumors where the picture is not covered by cardiovascular interference. Mediastinal, pleural and costal tumors have been explored. Pulmonary tumors give the best results, they fixe in 93% of the case. All the mediastinal tumors have capted the bleomycin but the authors insist on the fact that the fixation was very light even when the tumor was a large one. The exploration of pleural and costal tumors was less interesting. In conclusion, the Bleo-57Co scintigraphy, gives indications about the volume of the tumor and its spread in the organism. By this method, we can diagnose malignancy in tumor. It can be used to survey cancer patients which have been treated. Nevertheless the long half-life (270 days) and the lack of specificity of the Bleo-57Co for the malignant tumors, justify discussion about indications and the results of such an exploration.

Bleomycin↗
PubMed1975

[Influence of inaccuracy of certain parameters on dose distribution in telecobalt therapy (author's transl)].

Progress in dosimetry and in radiobiology together with the evolution of radiation generators led to adopt very elaborated radiotherapy protocols. However, the therapist should have confidence in these protocols on condition that irradiation parameters are strictly respected. For obvious reasons, this is impossible despite the meticulous rules. In this, paper, we therefore intend to study the role of the angle of incidence on the actual distribution of doses; we also study the inaccuracy of certain parameters recorded during preparation for the therapy or shown during successive irradiation courses. In this paper we retain only errors which can be easily quantified. These are errors concerning the irradiation apparatus (source to skin distance, angle of the rays, field dimension) and those due to factors related to the patient treated: contour measurement, entrance point of rays and positional changes of the patient. The different errors can be associated in various ways for a given therapy protocol. For the same reason, an isodose of a given nominal value will have several curves. All these tracings are lined by two curves which we call "superior and inferior envelops": these border the "incertitude area". It can be said that at the end of the treatment, the given isodose lies in this area; it is however impossible to define its form or exact position. A few examples in the text illustrate these results and show the possible practical angles of incidence. If we assume that errors during successive irradiations are distributed at random, a certain compensation is noted and the "areas of incertitude" decrease. But if the errors are constantly on the same side, as is sometimes the case, the dose distribution can be very different from that predicted in the dosimetric protocol.

Breast Neoplasms↗