42 research outputs found

    Carcinome métaplasique du sein : à propos d’un cas

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    Le carcinome métaplasique du sein est une tumeur maligne primaire rare et agressive, représentant 0,2-5% de tous les cancers du sein. Cette tumeur maligne est caractérisée par la présence histologique d'au moins deux types cellulaires, généralement des composants épithéliaux et mésenchymateux. Nous rapportons le cas d’une patiente qui présentait un carcinome métaplasique du sein droit. A travers ce cas et une revue de la littérature, les caractéristiques anatomo-cliniques, radiologiques, thérapeutiques et évolutives seront discutées.Les variantes métaplasiques sont agressives, chimiorésistantes et ont une forte propension à métastaser ainsi qu’un risque de récidive locale plus élevé, rendant ainsi leur pronostic plus sombre que les carcinomes du sein non métaplasiques c'est-à-dire, les carcinomes canalaires invasifs. Même si les carcinomes métaplasiques du sein sont traités de la même manière que les carcinomes invasifs, il n’en reste pas moins que leur prise en charge reste difficile et qu’il n’existe pas de standard thérapeutique. Le principal traitement reste la chirurgi

    Global thermodynamic behaviour of supercritical fluids: example of methane and ethane

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    Do to the fluctuations associated with the critical region of fluids. The behavior of thermodynamic properties these can not be predicted by mean field theories. To do so, a global equation of state based on the crossover model has been used. This equation of state is formulated on the basis of comparison of selected measurements of pressure-density-temperature data, isochoric and isobaric heat capacity of fluids.The model can be applied in a wide range of temperatures and densities around the critical point for ethane and methane. It is found that the developed model represents most of the reliable experimental data accurately

    Development of a hexavalent chromium ISFET sensor with a polymeric membrane including tributylphosphate

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    International audienceThis paper presents a first report on chromium ISFET (ion-sensitive field effect transistor) based on a polymeric membrane (siloprene) including an ionophore (tributylphosphate) sensitive for hexavalent chromium. The sensor sensitivity as a function of the pH was studied; its value is minimum in a pH interval from 5.5 to 7.5. The sensitivity for hexavalent chromium was found to be 15 mV/Ioga(Cr6+) in the range of 10(-4) to 10(-2) M. The detection limit was found to be 10(-5) M. The studied interfering ions are Pb(II) and Cd(II) that do not represent a great perturbation upon the response for hexavalent chromium. (c) 2005 Elsevier B.V. All rights reserved

    Chemical composition, antioxidant and insecticidal activities of a new essential oil chemotype of Pinus nigra ssp. mauritanica (Pinaceae), northern Algeria

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    Essential oil (EO) of aerial parts (twigs and needles) of an Algerian-Moroccan endemic pine Pinus nigra Arn. ssp. mauritanica (Mair. & Pey.) (Pinaceae) collected in Northern Algeria were extracted by hydrodistillation (HD) and solid phase micro-extraction (SPME). The compounds were analysed using Gas Chromatography (GC) and GC-Mass Spectrometry (GC-MS). The mean oil yield was 0.23%, for twigs and 0.47% for needles. 83 and 91 compounds have been identified for needles and twigs respectively. Chemical divergences from all other studied Black pines worldwide were observed in needles where the major components identified by HD are β-caryophyllene (26.2%), germacrene D (17.2%), α-pinene (9.4%) unveiling a new chemotype. Significative qualitative and quantitative differences were observed in chemical composition, depending on both technics HD and SPME. Twigs showed a higher potential for the antioxidant activities DPPH, ABTS and β-carotene system than EO needles. In other hand, needles revealed a higher activity for all concentrations than twigs with significant differences (p < 0.05). For phosphomolybden tests, both EOs exhibited more significant antioxidant potential compared to the DPPH, ABTS, β-carotene and reducing power systems. Noticeable insecticidal effects with variable rate depending on used plant parts, concentration, duration and frequency of exposure were also observed

    Characterization of DNA Bio-bonds for Meso-Scale Self-assembly

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    Abstract — In this paper, we have investigated the use of DNA hybridization as the basis for the production of new mesoscale components. AFM experimental results are studied and compared to two theoretical approaches: molecular and thermodynamic. We explain how and why DNA hybridization process can provide a good bond to self assemble components, and how molecular modelling methods allow further understanding of the physical mechanism of this process. Furthermore, the strength interaction of DNA complementary strands is measured and analyzed using statistical tools. These results are then compared to the theoretical approaches. I

    SILAR deposition of Ni(bpy)3X: {X = (NCS)2, (Fe(CN)5NO), and (Ag(CN)2)2} thin films on glass substrates

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    The authors focused on the preparation of thin layers based on hybrid materials (organometallic complexes) deposited onto glass substrates. The deposition experiments of [Ni(bpy)3](NCS)2, [Ni(bpy)3](Ag(CN)2)2, and [Ni(bpy)3](Fe(CN)5NO) were performed on glass slides (18 mm × 18 mm) by successive ionic layer adsorption and reaction (SILAR) method. The influence of some parameters, such as dipping cycle numbers (30, 60, and 120 dipping cycles), temperature (20°C, 30°C, 40°C, and 50°C), precursors concentration (10−3, 10−2, and 10−1 M), and the nature of the counteranions (NCS−, [Fe(CN)5NO]−2, [Ag(CN)2]−) were studied. Different methods (UV-Vis, SEM, FTIR, and XRD) were used to characterize the deposited layers to determine the absorption coefficient (α) and gap energy (Eg) of the materials

    Assessment of the physiological markers, oxidative stress and neurotoxic effects of nematode Anisakis sp. on the Luciobarbus callensis (Teleosts, Cyprinids) in northeast of Algeria

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    Our study focused on the effect of parasites on the antioxidant system and their neurotoxic effect in Luciobarbus callensis (Teleosts, Cyprinids). In this context, cellular biomarkers, acetylcholinesterase (AChE), catalase (CAT), molecules H2O2 as well as morphophysiological markers (condition factor (FC), hepatosomatic index (HSI), splenosomatic index (SSI), viscerosomatic index (VSI) were analyzed in fish infested with L3 larvae of Anisakis sp., nematodes of marine organisms, captured in Lake Oubéira (Algeria). The results showed a significant decrease in AChE activities in the heart (68 % p < 0.05) and muscles (81.55 % p < 0.05) in infested fish compared to those recorded in reference fish. In contrast, splenic AChE levels were significantly induced. CAT levels were significantly decreased in the spleen (73 % p < 0.05) and intestine (56 % p < 0.05) of fish parasitized by Anisakis sp. compared to healthy fish. HSI and SSI were significantly higher in healthy fish. On the other hand, Anisakis sp. had no significant effect on FC and VSI at the time of sampling. This study suggests that antioxidant defense disorders (CAT), due to a direct inhibitory action of nematode toxic products on this molecule and an increase in ROS production in these animals, leading to a high pro-oxidant state (H2O2), causing neurological effects (AChE) with enlargement of the spleen and liver of infested barb. In this regard, monitoring the effect of parasitic infections on physiological and biochemical marker profiles can be a crucial means of assessing fish health under natural conditions; to ensure the conservation and sustainability of aquatic biodiversity, including fish farming and artificial production

    Utilisation de l’essai des comètes pour la surveillance des milieux aquatiques – problématique de la conservation des échantillons

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    Les milieux aquatiques constituent le réceptacle d’un grand nombre de contaminants, anthropiques et naturels, pouvant être dangereux pour les organismes qui y vivent
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