Étude de deux facteurs inhibant la production de Tilapia melanopleura Dum

Résumé L'observation de différences de rendement entre centres piscicoles installés dans la Cuvette forestière congolaise conduit à l'étude, au centre de Yaekama, de deux facteurs: le chaulage qui éléve le pH et la présence d'un fond sableux qui diminue la suspension argileuse.On constate d'abord qu'il faut minimiser le débit d'alimentation en eau, et qu'une analyse de la covariance permet d'augmenter, dans de fortes proportions, la précision des essais piscicoles.L'élévation du pH entraîne une nette augmentation de la consommation en feuilles de manioc et, par conséquent, du rendement.En présence de sable, la consommation de nourriture augmente légèrement et le coefficient de transformation s'améliore. I1 en résulte de meilleurs rendements que dans les étangs à fond argileux.On observe, en outre, l'absence d'interaction entre les deux facteurs.

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Summary Production discrepancies of fish farming in the Congo woods lead, in the Yaekama center, to the study of two factors: liming that raises the pH and the existence of a sand bottom that decreases the clay suspension.We observe that we must minimize the supply of water and that a covariance analysis enables the increase of the precision in fish farming research.A pH raise conducts to a stimulation of the fish feeding and consequently of the final production.Even so a sand bottom increases the food consumption and also the fish production.We do not observe any interaction between the two factors under study.

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Ingénieur des Eaux et Forêts I. A. Gx., Assistant à la Division d'Hydrobiologie piscicole de l'I.N.É.A.C. France     

Les symptômes de premier rang de la schizophrénie: de la clinique à l’approche expérimentale

Theoretical models about action monitoring and action attribution developed over the last ten years have given a new framework in the understanding of first-rank symptoms of schizophrenia, as described by Kurt Schneider. Impaired action attribution has been demonstrated in patients with first-rank symptoms. Moreover, positron emission tomography studies have revealed that the cortical network involved in action attribution processes in normal subjects is not correctly activated in patients with first-rank symptoms. These results demonstrate that these symptoms are related to cognitive and cerebral correlates and they shed new light on the understanding of psychotic symptoms.     

La psychothérapie individuelle de la schizophrénie: mise en perspective de son histoire, de ses développements récents et de ses orientations nouvelles

Empirical study of long-term outcomes for persons with schizophrenia suggests that recovery is often possible. This literature also emphasizes that recovery may involve different kinds of experiences for different people with the same psychiatric condition. For some, recovery may mean symptom remission while for others it may be reflected by the achievement of psychosocial milestones. For yet others, however, to recover can involve subjective changes in how those persons experience themselves as meaningful agents in the world. For some, to recover could be to reclaim a full sense of self, a sense of self that permits to engage in relationship with others and the rigors of daily life. In this chapter, we review the potential of individual psychotherapy to address the more subjective aspects of recovery related to sense of self. We first review literature on the effectiveness of psychotherapy for persons with schizophrenia. We then discuss literature on the larger issue of how decrement in personal narrative metacognition may underpin some of the disturbance in sense of self observed in schizophrenia. Finally, we focus on how psychotherapy could be conceptualized and adapted to help enrich self-experience by addressing narrative and metacognition. Directions for future research are discussed.     

Étude dosimétrique de préparations de médicaments radiopharmaceutiques au 68Ga

AimProduction of ⁶⁸Ga-radiopharmaceuticals is a rapidly growing field in France. However, operators may already be involved in other radiopharmaceutical activities. It is thus necessary to know the exposure of this new activity.Material and methodsFor passive dosimetry, a radiophotoluminescent (RPL) dosimeter, a thermoluminescent (TLD) chip, 2 TLD rings and a passive dosimeter for crystalline were used. For active dosimetry, an extremity dosimeter and a whole body dosimeter were used. This study was performed during semi-automatized production of ⁶⁸Ga-investigational medicinal products. Values were normalized to 500MBq manipulated (median activity using a 1850MBq ⁶⁸Ga-generator), 60 radiosynthesis (maximum enrollment ability of our center) and 2 operators. A LB123 proportional counter was used for quantification of external exposition to 10MBq ⁶⁸Ge and internal exposition by inhalation was theoretically assessed. ⁶⁸Ga emission attenuation by collective protection equipments was also discussed.ResultsConsidering passive dosimetry, the equivalent dose to extremities was 21.75 ± 0.34 mSv, the whole-body effective dose was 0.189 ± 0.011 mSv and the dose to crystalline was 0.925 ± 0.009 mSv. Considering active dosimetry, the equivalent dose to extremities was 8,75 ± 0.12 mSv and the whole-body effective dose was 0,088 ± 0.009 mSv. Total exposure to ⁶⁸Ge was 1.75 μSv.ConclusionIn our hands, ⁶⁸Ga is a directly transposable activity in radiopharmacies already equipped for ¹⁸F because of a dosimetry complying with regulatory limits and suitable radiation protection of collective equipments.     

Épidémiologie et facteurs de risque des cancers thyroïdiens

Over the last two decades, the dramatic increased incidence of thyroid cancer, in France and over the world, is well documented, especially due to an increase of papillary microcarcinomas. The spread of ultrasonographic and cytological procedures, the extensiveness of thyroidectomies lead to a better preoperative selection of patients and to the discovery of occult microcarcinomas at histology. This impact of medical practices is associated with a possible role of risk factors such as a neck radiation history, genetic ethnic and hormonal factors and more recently pollutants and chemicals agents that disrupt thyroid function.     

Étude de la variabilité de la clairance hépatique de la mébrofénine-99mTc en scintigraphie hépatobiliaire

AimThe purpose of this study was to investigate some of the parameters likely to influence mebrofenin-^99mTc hepatic clearance calculation and inter-and intra-observers reproducibility.Materials and methodsHepatic clearance (%/min m²) of 30 scintigraphies was calculated from the values of hepatic, cardiac, and total activities, according to the method recommended in the literature. We studied: 1) impact of injection–acquisition delay variations; 2) acquisition type: anterior face only (FA) or geometric mean (GM); 3) clearances calculated according to four different body surface area (BSA) formulas; 4) intra-and inter-observers reproducibility for three observers (two evaluations for each observer).Results1) Clearance differences between different studied intervals were statistically significant, more important if the studied interval was far from reference interval (150–350 secondes) and even more when the interval studied was too early (110–310 secondes). 2) There was a statistically significant difference between clearance calculated using either FA or GM datasets (0.85 %/min m²). 3) There were small but statistically significant differences for four of the clearance comparisons using different BSA formulas. 4) Despite differences in size of cardiac and hepatic regions of interest (ROI), intra-observer reproducibility of hepatic clearance was excellent for each observer. Inter-observers reproducibility was also excellent (r = 0.982).ConclusionHepatic clearance of mebrofenin-^99mTc appears to be a highly reproducible method provided that acquisition and clearance calculation are standardized. It provides additionnal functional information to morphological and biological data usually performed before major hepatectomy. Thereby, the definition of a standardized protocol would enable realization of multicentric studies.     

Évaluation de la tomoscintigraphie de perfusion pulmonaire couplée à la tomodensitométrie dans la prédiction de la fonction respiratoire postopératoire

IntroductionThe aim of our study was to evaluate the performances of pulmonary perfusion single photon emission computed tomography-computed tomography (SPECT-CT) with semi-automatic analysis for preoperative assessment for lung cancer.Materiel and methodThirty-five patients underwent preoperative lung perfusion scintigraphy (planar and SPECT-CT acquisition) from august 2016 to December 2017. Predicted postoperative forced expiratory volume in one second (ppoFEV1 and FEV1) by both methods were compared between each other and with the actual FEV1 measured 3 months after surgery. We also evaluated interobserver reproductibility of SPECT-CT semi-automatic segmentation software and the concordance of the data simulating reductions of 30 and 50% of acquisition time.ResultsFor 30 lobectomies and 5 pneumonectomies, the mean ppoFEV1 was 69%, a difference with actual ppoFEV1 of ?8% for SPECT-CT and ?6.77% for planar (P < 0,001). Both methods were well correlated, correlation coefficient was 0,827, 95% CI [0.686–0.909] but underestimated the actual poppFEV1. For SPECT-CT, interobserver reproducibility was excellent for pulmonary and lobar evaluation. The lobar functions, without 30 and 50% of the time acquisition, had absolute difference < 3% in comparison to native data.DiscussionWe did not prove SPECT-CT superiority on planar scintigraphy, actual FEV1 being difficult to predict because of confounding factors. But this exam could be useful before lobectomy and in cases of heterogeneous perfusion. Easily made, this method is reproducible even on data simulating a reduction of 50% of time acquisition.     

Étude cinétique de l'hypersensibilité de type retardé dans la candidose expérimentale de la souris

Mice were inoculated with different quantities of blastospores ofCandida albicans by subcutaneous or intravenous ways. Delayed hypersensitivity was then studied during the course of infection by means of the inhibition of macrophage spreading test. In the same time retrocultures were done from kidney material, target organs in the experimental candidiasis. The results obtained in this way enabled the authors to think that cellular immunity plays a role in this experimental model as described by Mackaness.

Travail de l'Unité 42 de l'INSERM et du Groupe de Mycologie Fondamentale et Appliquée de LILLE.     

Étude expérimentale des variations de la teneur en eau au cours de la déshydratation et de la réhydratation chez la Fougère:Notochlaena vellea R. Br.

Experimental Study of changes in water content during dehydration and rehydration of the Fern: Notochlaena vellea R. Br.—This study takes place after studies made on otherPolypodiaceen Ferns. We have shown that, in these ferns, the survival duration was longer for the subterranean organs than for aerial ones. The problem was to show that this difference is due to a lower dehydration of the subterranean tissues. As far as we looked at the total water deficiency, we did not find any significant difference between the leaves and the meristematic parts of the subterranean organs: the main difference is the rate of rehydration which is higher in subterranean parts.     

Conséquences de la chimiothérapie anticancéreuse sur la fertilité de la femme

Sterility is a potential toxic effect of chemotherapy. This risk is well established for alkylating agents, but is less clearly defined for anthracyclines, methotrexate and fluorouracil and poorly defined for alkaloids, platinum, etoposide and taxanes. The main predictive factors for ovarian toxicity are the additive effect of cytotoxic drugs, the cumulative dose of each drug and the patient’s age. This effect of chemotherapy is evaluated on menstrual cycles, hormonal assays and the number of pregnancies observed in patient cohorts. Chemotherapy induces destruction of oocytes and granulosa cells. In mice, it has been shown that adriamycin may induce oocyte apoptosis, which can be prevented by modulation of cycle cell signalling (dysregulation of Bax gene or, on the contrary, expression of its antagonist gene Bcl-2 or inhibition of apoptosis with sphingosine-1-phosphate or caspase inhibitors). Clinical data in the literature are usually based on retrospective studies and are somewhat confused: global fertility after MOPP chemotherapy for Hodgkin’s disease is about 20%, adjuvant chemotherapy with CMF, F(A)C or TAC for breast cancer induces amenorrhea in 50% to 70% of cases, PVB or BEP chemotherapy for ovarian germ cell tumors has little effect on fertility when the uterus and one ovary can be preserved, and the majority of women treated with methotrexate, actinomycin D or various combinations for persistent trophoblastic disease remain fertile. Preservation of fertility is a major goal for cancer patients receiving chemotherapy: in vitro fertilization could preserve the couple’s fertility, but is usually not feasible as it would delay initiation of chemotherapy until after stimulation of ovulation; oocyte or ovarian tissue cryopreservation is at the stage of research; oral contraceptives have not been demonstrated to be effective to preserve ovarian function; gonadotropin releasing hormone (GnRH) agonists prevent cyclophosphamide toxicity in rat and monkey ovaries, and a few pilot clinical studies suggest that chemotherapy-induced amenorrhea could be prevented by administration of GnRH analogues simultaneously to chemotherapy, but randomised studies are necessary.