Evaluation d'une alimentation à risque vasculaire, à l'aide d'un questionnaire validé, dans une population de médecine générale / Marie Carsin

RENNES1-BU Santé (352382103) / SudocSudocFranceF

Sédimentation phosphatée actuelle dans le lagon confiné de l'île Clipperton (Océan Pacifique). Datations, sédimentologie et géochimie

The almost-atoll of Clipperton, 1,800 km from the Mexican coast, is characterized by an enclosed lagoon, receiving marine waters only when catastrophic events of very high energy, such as tempests, tropical storms, hurricanes or tsunamis occur. Owing to a high rainfall climate, the lagoon is, in fact, occupied by a meromictic lake, elliptically shaped, with axes of 3 km and 3.5 km. It has its own particular hydrology, showing salt water lenses topped by nearly fresh superficial waters. The ecology of the lake is a fresh water one, with Charophytes, Chlorophytes, land crabs (Geocarcinus), dragonflies. As a consequence of this particular climatology and hydrology, several sedimentological phenomena can be observed : late diagenesis on the ancient carbonates of the atoll, early diagenesis, and carbonate but chiefly phosphate sedimentation on the shores of the former lagoon, now a lake. The climatology and the presence of the meromictic lake in its center lead to an early carbonate diagene¬ sis which acts on modern coral deposits as soon as they are no longer under marine influence. Carbonate diagenesis also includes late diagenesis. The low salinity surface lagoon waters attack the reef rim and cause a dissolution of all the aragonite material in the ancient coral levées. This process is indicated by low cliffs at different altitudes surrounding the lagoon. An early diagenesis seems to occur causing magnesium and magnesium mixed carbonate neogenesis (magnesite and kutnahorite) within the present lagoonal deposits together with the present phosphate deposits. The present Clipperton lagoon seems to be the site of littoral phosphate particle deposition. Following sedimentary logic, these modern phosphate deposits are located along the lagoon bays on the leeward side of the windward coral rim i.e. in the NE and SE embayments of the lagoon. The deposits form an accretion prism resting on the ancient coral levees, forming phosphated tidal flats which are highly bioturbated by land crabs. These observations on the modern sedimentation allow us to present two main hypothesis : (1) It is possible that the phosphate is a result of the reworking of the old mines (during mining a small amount was dumped in the lagoon because of its low phosphate content) ; (2) it is also possible that the Clipperton lagoon is now producing phosphate from the meromictic lake waters ; this neogenesis might be similar to the one which could have occured on other oceanic islands for older deposits. As to the origin of the phosphate ions, several hypotheses can be made, (a) Phosphorus can come from the very thin crust deposits of guano left by birds. Samples of guano are analysed to compare them with phosphate deposits, (b) Phosphorus can come from the reworking of soils which were covering the island during the numerous quaternary periods of emergence. An attempt can be made to resolve this problem by elemental analysis of present phosphate deposits and volcanic rocks, (c) Finally, phosphorus can be of mixed origin, from guano and from matured soils of volcanic origin and enriched in phosphate. Phosphorus is accompanied by numerous ions : Zn, Ba, B, 5r, La etc... All these ions could have been leached into the lagoon waters and there allow apatite neogenesis. (d) The hypothesis, based on the existence of upwelling waters, is rejected because no upwelling exists around oceanic islands.Situé par 109°12'34" de longitude Ouest et 10°18'41" de latitude Nord, le presqu'atoil de Clipperton est caractérisé par un lagon fermé ne recevant d'apports marins océaniques que lors d'événements exceptionnels de très forte énergie : tempêtes, cyclones, ouragans ou tsunamis. Suite à une climatologie caractérisée par une très forte pluviosité, le lagon est, en fait, occupé par un lac méromictique, elliptique, de 3 km en moyenne de diamètre, et montrant une hydrologie particulière avec stratifications de lentilles d'eaux salées surmontées par des eaux presque douces en surface. L'écologie du lagon est une écologie dulçaquicole avec charophytes, chlorophytes, crabes terrestres, libellules, etc... Conséquences de cette climatologie particulière et de la présence de la nappe d'eau douce de surface, plu¬ sieurs phénomènes sédimentologiques s'observent : une diagenèse tardive sur les "anciens carbonates" de l'atoll, une diagenèse précoce carbonatée et enfin une sédimentation carbonatée mais surtout phosphatée sur les rives de l'ancien lagon. La climatologie de Clipperton ainsi que la présence d'un lac méromictique en son centre provoquent une diagenèse précoce qui affecte les dépôts coralliens actuels dès qu'ils ne sont plus soumis à l'action de la mer. On observe ainsi rapidement un noircissement des fragments de coraux cassés qui deviennent extrêmement acérés et pointus par suite de la dissolution de l'aragonite et par suite de l'action des cyanobactéries et bactéries. Cette action dissolvante de l'eau du lagon vis-à-vis de l'aragonite se marque aussi par la présence de petites falaises décimétriques à la périphérie du lagon, falaises taillées dans une rudite corallienne très grossière à ciment phosphaté. L'érosion fait petit à petit reculer cette falaise intérieure et on observe ainsi des blocs basculés et effondrés de roche corallienne dans l'eau du lagon. La diagenèse précoce semble impliquer aussi la néoformation de carbonates magnésiens simples et doubles (magnésite et kutnahorite) dans les dépôts lagonaires. De plus, le lagon actuel de Clipperton semble être le siège d'un dépôt littoral actuel de particules phosphatées. Dans la logique sédimentaire, ce dépôt de phosphate se situe dans les baies lagonaires situées sous le vent des côtes aux vents, c'est-à-dire dans les anses NE et SE du lagon. Le dépôt forme un prisme d'accrétion s'appuyant, côté extérieur océanique, sur les rides coralliennes anciennes en formant des replats d'estran ou "Tidai Flats" phosphatés ; côté intérieur lagonaire, le dépôt se termine par un talus qui se raccorde au fond du lagon. Deux hypthèses peuvent être formulées pour l'origine de cette sédimentation actuelle. (1) 11 est possible que ce soit un remaniement issu des anciennes extractions de phosphates, dont on sait qu'une petite quantité était rejetée par suite de sa trop faible teneur. (2) 11 est possible aussi qu'on assiste à une néogenèse de phosphate dans le lagon de Clipperton, à partir des eaux du lac méromictique, néogenèse identique à celle qui a pu se produire antérieurement sur d'autres îles océaniques, pour les dépôts anciens de phosphates. Quant à l'origine des ions phosphates, plusieurs hypothèses peuvent aussi'être formulées, (a) Le phosphore peut provenir des enduits très minces de guano que déposent les oiseaux. Des prélèvements de ce guano sensu stricto, faits à Clipperton in situ, essaient de lever l'ambiguïté, (b) Le phosphore peut provenir du remaniement des sols qui recouvraient cette île lors des multiples émersions quaternaires. La comparaison des oligo-éléments dans le dépôt actuel de phosphate et dans la roche volcanique confirme cette hypothèse. (c) Enfin, un apport mixte, à partir de guano et à partir de sois d'origine volcanique et enrichis en phosphates peut aussi être invoqué, le phosphore et son cortège géochimique se retrouvant actuellement dans les eaux du lagon par lessivage et permettant la néogenèse d'apatite. Le presqu'atoil de Clipperton semble donc présenter un modèle actuel de sédimentation phosphatée.Bourrouilh-Le Jan Françoise G., Carsin Jean-Louis, Niaussat Pierre-Marie, Thommeret Yvonne. Sédimentation phosphatée actuelle dans le lagon confiné de l'île Clipperton (Océan Pacifique). Datations, sédimentologie et géochimie. In: Phosphorites. Sixth International Field-Workshop and Seminar on Phosphorites. I.G.C.P. 156. Maroc-Sénégal, oct.-nov. 1983. Strasbourg : Institut de Géologie – Université Louis-Pasteur, 1985. pp. 109-124. (Sciences Géologiques. Mémoire, 77

Chyme Reinfusion in Intestinal Failure Related to Temporary Double Enterostomies and Enteroatmospheric Fistulas

Some temporary double enterostomies (DES) or entero-atmospheric fistulas (EAF) have high output and are responsible for Type 2 intestinal failure. Intravenous supplementations (IVS) for parenteral nutrition and hydration compensate for intestinal losses. Chyme reinfusion (CR) artificially restores continuity pending surgical closure. CR treats intestinal failure and is recommended by European Society for Clinical Nutrition and Metabolism (ESPEN) and American Society for Parenteral and Enteral Nutrition (ASPEN) when possible. The objective of this study was to show changes in nutritional status, intestinal function, liver tests, IVS needs during CR, and the feasibility of continuing it at home. A retrospective study of 306 admitted patients treated with CR from 2000 to 2018 was conducted. CR was permanent such that a peristaltic pump sucked the upstream chyme and reinfused it immediately in a tube inserted into the downstream intestine. Weight, plasma albumin, daily volumes of intestinal and fecal losses, intestinal nitrogen, and lipid absorption coefficients, plasma citrulline, liver tests, and calculated indices were compared before and during CR in patients who had both measurements. The patients included 185 males and 121 females and were 63 ± 15 years old. There were 37 (12%), 269 (88%) patients with EAF and DES, respectively. The proximal small bowel length from the duodeno-jejunal angle was 108 ± 67 cm (n = 232), and the length of distal small intestine was 117 ± 72 cm (n = 253). The median CR start was 5 d (quartile 25–75%, 2–10) after admission and continued for 64 d (45–95), including 81 patients at home for 47 d (28–74). Oral feeding was exclusive 171(56%), with enteral supplement 122 (42%), or with IVS 23 (7%). Before CR, 211 (69%) patients had IVS for nutrition (77%) or for hydration (23%). IVS were stopped in 188 (89%) 2 d (0–7) after the beginning of CR and continued in 23 (11%) with lower volumes. Nutritional status improved with respect to weight gain (+3.5 ± 8.4%) and albumin (+5.4 ± 5.8 g/L). Intestinal failure was cured in the majority of cases as evidenced by the decrease in intestinal losses by 2096 ± 959 mL/d, the increase in absorption of nitrogen 32 ± 20%, of lipids 43 ± 30%, and the improvement of citrulline 13.1 ± 8.1 µmol/L. The citrulline increase was correlated with the length of the distal intestine. The number of patients with at least one liver test >2N decreased from 84–40%. In cases of Type 2 intestinal failure related to DES or FAE with an accessible and functional distal small bowel segment, CR restored intestinal functions, reduced the need of IVS by 89% and helped improve nutritional status and liver tests. There were no vital complications or infectious diarrhea described to date. CR can become the first-line treatment for intestinal failure related to double enterostomy and high output fistulas

Drug hypersensitivity in children: a retrospective analysis of 101 pharmacovigilance reports

International audienceOur objective was to describe and discuss management of recent cases of drug hypersensitivity in children reported in a pharmacovigilance center. Two pediatric allergy units conducted a collaborative retrospective analysis of 101 adverse drug reactions reported to a regional pharmacovigilance center between January 2016 and July 2019. Time lapse between hypersensitivity reaction onset and allergy consultation varied from 1 month to 12 years. Sixty-two patients (61.4%) presented with immediate reactions, 11 (10.9%) with non-immediate reactions, and 28 (27.7%) had reactions impossible to classify through medical interview. Overall, 92 children (91%) were explored for simultaneously administered drugs. All 113 prick tests were negative, and 2 were uncertain. Among 108 intradermal tests, 2 were positive to penicillin and to an iodinated contrast medium, 105 were negative, and 1 was uncertain. Overall, 129 drug provocation tests were proposed. Nine provocation tests among 80 were positive (11.25%): 6 to penicillin, 1 to sulfonamide antibiotics, and 2 to non-steroidal anti-inflammatory drugs; the remaining 71 were negative. No severe reaction was observed during these tests. Finally, drug allergy was only retained in 11 reported cases (10.9%). Conclusion: These pharmacovigilance reports show the difficulty in defining drug allergy in children only by anamnesis, and that explorations, particularly provocation tests, should take place at a reasonable time lapse after drug hypersensitivity reaction onset. What is Known: True drug allergy is rarely observed in children. Absence of full workup leads to falsely labeling children as ``allergic.'' What is New: Short time lapse between hypersensitivity onset and consultation improves classification of pediatric allergy. Timely allergy consultations are essential, and tests are useful to confirm or exclude pediatric allergy

Magnetoencephalographic studies of two cases of diffuse subcortical laminar heterotopia or so-called double cortex.

International audienceTwo cases (a young male and a girl, suffering intractable epilepsy) of diffuse subcortical laminar heterotopia, or so-called double cortex (DC) have been investigated using magnetoencephalography (MEG). MEG confirmed involvement of both cortices (hetero- and normocortex) in the genesis of interictal spikes, and, according to the heterogeneity of DC syndrome, some differences were observed: spike initiation in the normocortex and latter involvement of the heterotopic cortex in the man, and rather a cancellation in both cortices in the girl. In addition, participation of heterotopic cortex in physiological activities could be demonstrated in the man

Use of epinephrine in emergency department depends on anaphylaxis severity in children

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Use of epinephrine in pediatric emergency departments depends on anaphylaxis severity: Meeting Abstract: PD0234

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