Densités de primates en forêt guyanaise. Test d'une méthode d'estimation par transect

The results of a classical transect method designed to evaluate primate density are compared with estimates obtained from long-term studies on three species within a community inhabiting an undisturbed rain forest (French Guiana). Combining results of both methods, the total density of the primate community, which includes six species, is about 70 individuals per square kilometre. The concordance of data noted in Alouatta seniculus, Cebus apella and Saguinus midas, makes the transect method a reliable approach to low primate densities overall. However, it requires that long cumulative distances are walked and does not guarantee that rare species will not be missed. The predominance of Alouatta within the community, as observed in numerous Amazonian communities, is interpreted in relation to the nutritional quality of its environment and weak feeding competition between primate species.     

Observation sur la fréquence en forêt dense équatoriale

Sans résuméReçu par la rédaction le 30.X.1953.     

Une méthode d'amplification génique isotherme

A gene amplification technique applied to the detection of HIV and which can be implemented without programmable thermocyclers is described. The reaction products are high molecular weight strands of DNA that can be detected using simple methods, even without electrophoresis. This is a promising technique for in situ amplification experiments. Our findings show that this amplification method is compatible with the temperature levels encountered in living cells. This technology could thus be the basis for a new class of drugs intended for treatment by gene therapy of certain diseases, including malaria and AIDS.     

La méthode statistique dans la protophysiologie

Sans résumé     

La forêt alluviale du mont-dieu

Sans résuméReçu par la rédaction le 15.XII.1958.Etude subventionnée par le Fonds National de la Recherche Scientifique de Belgique, dans le cadre des Recherches sur les migrations des Flores et des Végétations dans le Bassin de la Meuse.     

Ciblage peptidique en oncologie nucléaire : intérêt de la modélisation moléculaire

Peptidic receptor targeting in nuclear oncology has been significantly improved the last 20 years. A better in-depth knowledge of peptidic receptor has permitted more extensive research and development of new radioligands. The different published studies showed the interest of radiolabelled peptide development but also the difficulties to obtain a radiopharmaceutical with pharmacologic and pharmacokinetic properties adapted to clinical applications in diagnosis and internal radiotherapy. Based on the literature, the most applied methodology is to modify the structure of the endogenous ligand iteratively and to synthesize various derivatives radiolabelled peptide tested one by one. We chose to address the issue of optimization of radiolabelled peptide analogues from a different recent method via molecular modelling and for our purpose more specifically the targeting of the peptide receptor cholecystokinin/gastrin.     

Existe-t-il une hêtraie ‘Méditerranéenne’ distincte des autres forêts de hêtre en Europe occidentale?

The study area is at the southern limit of the beech area, between the rivers Rhône in France and Ebro in Spain. From an analysis of the occurrence of beechwoods in this region and the pluviometric climate, it appears that part of the beechwood is found in a dry climate, which is still mediterranean. This argument seems sufficient to justify the existence of a ‘mediterranean’ beechwood, at least on a climatic level. Beechwood when occurring in a dry climate has special characteristics:

- The development of the wood differs with the climate. Young beeches need shadow in a dry climate; they can grow in full light in a moist climate.

- The floristic composition is different.

- The understorey of dry woods is less structured than that of moist woods.

- The genetic structure as measured in the enzymatic system Px₁ is polymorphic in the dry and monomorphic in the moist conditions studied.

It would be interesting to verify if the characters noted in a dry mediterranean climate are also present in dry atlantic or continental beechwoods. Since the mediterranean climate is drier and more unfavorable to beech than other climates, the particular characters of ‘dry’ beechwoods will be more pronounced near the Mediterranean.     

Intérêt du dosage des peptides natriurétiques en urgence dans la dyspnée aiguë

Acute dyspnea often leads to an emergency room visit. B-type natriuretic peptide (BNP) and its N-terminal fragment (NT-proBNP) are natriuretic peptide factors secreted by ventricular myocytes when pressure is exerted on the ventricular wall. BNP fights against the activation of the renin-angiotensin-aldosterone system, while NT-proBNP exhibits no activity in this regard. Elevated blood levels of these factors correlate with a variety of functional indices for left-sided heart failure. Several studies have demonstrated their usefulness as markers of left-sided heart failure, the main cause of acute dyspnea seen in emergency rooms. The diagnostic performance of BNP and NT-proBNP appears to be identical; it is, however, greater than that of the emergency room physician. BNP and NT-proBNP have high sensitivity and specificity in the diagnosis of acute heart failure. Briefly, when BNP is less than 100 pg/ml, heart failure is very unlikely (NT-proBNP <500 pg/ml); when it is greater than 400 pg/ml (NT-proBNP >2000 pg/ml); when it is greater than 400 pg/ml (NT-proBNP >2000 pg/ml), it is very likely. The early measurement of BNP in emergency room situations improves the care of patients presenting with acute dyspnea and makes it possible to reduce hospitalisation costs.     

Enquête nationale en médecine nucléaire : radiopharmaceutiques et activités utilisés en 2007 dans le secteur public

The Institute for radiation protection and nuclear safety (IRSN) and the National institute for health surveillance (InVS) have been collaborating since 2003 to provide updated data on medical exposure of the French population related to medical diagnosis. In this framework, a survey was carried out by IRSN in 2009 within all the 127 departments of nuclear medicine belonging to public hospitals. The rate of participation was high (72% of the departments). The first objective of this survey was to estimate the activity of these nuclear medicine departments (numbers and types of examination, according to their code in the French common classification for medical care). The second objective was to collect data related to the dose delivered to the patient for each type of examination. This article details this second part of the survey and presents, for the 32 most frequent types of examination, the radionuclide used and its chemical form, the average administered activity per examination and the activity range for the responding departments. When a French dose reference level exists, this survey showed that the average administered activity is in agreement with it, excepted for the ^99mTc thyroid scintigraphy with an administered activity close to twice the dose reference level (DRL). The dispersion of administered activity between the departments for a same type of examination depends on the type of examination, and is comprised between 2 and 10 for a 70 kg patient.     

Sur quelques propriétés physico-chimiques des protéines séparées des sérums par la méthode à l'acétone

Sans résuméCes diverses études conduisent toutes à cette conclusion que la séparation des protéines effectuée à basse température par la méthode dite à l'acétone de MM.Piettre etVila respecte l'intégrité des molécules protéiques.