26 research outputs found
Physiopathologie et pronostic des thromboses portales aprĂšs splĂ©nectomie chez lâenfant.
Il sâagit dâune Ă©tude analytique rĂ©trospective de 32 cas de splĂ©nectomie chez lâenfant, au service de chirurgie A de lâhĂŽpital dâenfants de Rabat, sur une pĂ©riode de 11 ans, de 2001 et 2012.
Notre travail a comme but, dâĂ©claircir les mĂ©canismes physiopathologiques : les facteurs et marqueurs de risque, ainsi que ceux pronostiques, de la thrombose de la veine porte aprĂšs splĂ©nectomie chez lâenfant.
Dans notre sĂ©rie, les facteurs de risques sont: lâĂąge aux alentours de 9 ans, le sexe masculin, le contexte de maladie hĂ©matologique surtout thalassĂ©mie et drĂ©panocytose, surtout de durĂ©e supĂ©rieure Ă 2 ans, le traumatisme per opĂ©ratoire de la veine splĂ©nique, lâhyperplaquetose post splĂ©nectomie et signes abdominaux dans un contexte fĂ©brile.
La corticothĂ©rapie ainsi que la complication par un abcĂšs splĂ©nique semblent ĂȘtre des facteurs de mauvais pronostic, tandis que la double thĂ©rapie par lâanticoagulant (hĂ©parine) et lâantiagrĂ©gant(Aspirine), change le pronostic vers la guĂ©rison totale sans rĂ©cidive.
La prĂ©vention nâest pas toujours efficace.
Nos résultats sont en harmonie avec ceux de la littérature, celle-ci rajoute comme facteurs de risque le diamÚtre préopératoire de la veine splénique ainsi que le taux bas des inhibiteurs de la coagulation
Effect of pyridine as advanced polymeric inhibitor for pure copper: adsorption and corrosion mechanisms
International audienceThe effect of pyridine (Pyr) on the corrosion of copper in 3 wt% NaCl was investigated using potentiodynamical anodic polarization, weight loss and morphological analysis. The Doehlert design simulation shows that Cpyr and immersion time are the significant factors. In addition, electrochemical measurements revealed that Pyr acts as a mixed-type inhibitor with more pronounced effect on anodic domain and the inhibition efficiency increases with increasing of inhibitor content. The adsorption of Pyr was found to obey the free polymerization during adsorption onto substrate surface. Surface characterization was performed using a scanning electron microscope and a Fourier transform infrared spectrometer, and Pyr has large negative charge in nitrogen and oxygen atoms, which results in a chemisorption of Pyr onto the copper surface and records around 97% of inhibition efficiency
Valorization of Pomegranate Peel Balls as Bioadsorbents of Dyes in Aqueous Media
Pomegranate peel balls were
evaluated as bioadsorbents for removal of Methylene Blue (MB) dye, a model
pollutant, from aqueous solutions. Adsorption levels off at 15.8 mg/g and the agrowaste-derived adsorbent can be recycled at least three times. The work conclusively shows
that in countries where pomegranate is available, the waste generated by the
fruit peel could be considered for future water filtration and environmental
protection.</div
Valorization of Pomegranate Peel Balls as Bioadsorbents of Dyes in Aqueous Media
Pomegranate peel balls were evaluated as bioadsorbents for removal of Methylene Blue (MB) dye, a model pollutant, from aqueous solutions. Adsorption levels off at 15.8 mg/g and the agrowaste-derived adsorbent can be recycled at least three times. The work conclusively shows that in countries where pomegranate is available, the waste generated by the fruit peel could be considered for future water filtration and environmental protection.</div
Valorization of pomegranate peel balls as bioadsorbents of methylene blue in aqueous media
International audienceThere is an ever-growing demand for biosourced adsorbents in environmental protection in order to remove organic and inorganic hazardous compounds. Herein, pomegranate peel balls were evaluated as bioadsorbents for the removal of methylene blue (MB) dye, a model pollutant, from aqueous solutions. Adsorption kinetics was investigated in relation to temperature, contact time, and pH of the solution. The results were found to fit pseudo-second order kinetics. The maximum adsorption capacity of the peel balls for MB was found to be 15.8 (98.8% dye removal), 15.6, 14.9, and 14.5 mg/g at 25, 35, 45, and 55 °C, respectively. Thermodynamic studies indicated that the sorption reaction was spontaneous and exothermic. Mechanisms of sorption include physical adsorption. These salient features conclusively show that, in countries where pomegranate is available, the waste generated by the fruit peel could be considered for future water filtration and environmental protection, therefore contributing to sustainable development
A combined experimental and theoretical studies of two new decavanadatet: (C6N2H9)4[H2V10O28]·4H2O and (C7H9NF)4[H2V10O28]·2H2O
Two novel organic-inorganic decavanadate materials with protonated amines were prepared from acidified aqueous solution and characterized by single crystal X-Ray diffraction, thermogravimetric analysis and IR spectroscopy. (C6N2H9)4[H2V10O28]·4H2O (I) and (C7H9NF)4[H2V10O28]·2H2O (II), were isolated in single-crystal form. For both compounds, the crystal packing is governed by the formation of various non-covalent intermolecular forces between decavanadate anions, organic cations and water molecules. For both compounds, Hirshfeld surface analysis and two-dimensional fingerprint plots indicate that the most important contributions to in the crystal packing for both compounds are from Oâ
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H/Hâ
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O and Hâ
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H bonds. Furthermore, topological study of weak non-covalent interactions properties was theoretically carried out using DFT. The determined HOMO and LUMO levels were to estimate the charge transfer within the structure. The photoluminescence properties and UVâVis absorption spectra have also been investigated. Both (I) and (II) possess photoluminescence properties and produce blue and green emissions, respectively, upon irradiation with violet light.With funding from the Spanish government through the âSevero Ochoa Centre of Excellenceâ accreditation (CEX2019-000917-S).Peer reviewe
Evolution of Electrochemical Behavior, Electrical Conductivity, and Microhardness of Electrodeposited W Coatings Enhanced by Ni During Long Immersion in 3% NaCl Media
International audienceThis paper deals with detailed physical and electrochemical properties of electroplated W enhanced by massive Ni coatings. Corrosion behavior of elaborated deposits in 3% NaCl solution is examined, as well as the influence of immersion time in corrosive media on the morphology, electrical conductivity, and microhardness of all coatings. Characterizations are carried out using atomic force microscopy, scanning electronic microscopy, energy dispersive spectroscopy, and X-ray diffraction analysis. The linear polarization curve and EIS during long-term immersion tests were used to identify and quantify corrosion compounds on surfaces. All obtained coatings corrode in the 3% NaCl solution, leading to uniform corrosion for the enhanced W coating, while this is not the case for the pure Ni film. The main corrosion products for the enhanced W coatings are NiO, Ni(OH)2 and WO3
Highly Selective Copper Ion Imprinted Clay/Polymer Nanocomposites Prepared by Visible Light Initiated Radical Photopolymerization
There is an urgent demand worldwide for the development of highly selective adsorbents and sensors of heavy metal ions and other organic pollutants. Within these environmental and public health frameworks, we are combining the salient features of clays and chelatant polymers to design selective metal ion adsorbents. Towards this end, the ion imprinting approach has been used to develop a novel nanohybrid material for the selective separation of Cu2+ ions in an aqueous solution. The Cu2+-imprinted polymer/montmorillonite (IIP/Mt) and non-imprinted polymer/montmorillonite (NIP/Mt) nanocomposites were prepared by a radical photopolymerization process in visible light. The ion imprinting step was indeed important as the recognition of copper ions by IIP/Mt was significantly superior to that of NIP/Mt, i.e., the reference nanocomposite synthesized in the same way but in the absence of Cu2+ ions. The adsorption process as batch study was investigated under the experimental condition affecting same parameters such as contact time, concentration of metal ions, and pH. The adsorption capacity of Cu2+ ions is maximized at pH 5. Removal of Cu2+ ion achieved equilibrium within 15 min; the results obtained were found to be fitted by the pseudo-second-order kinetics model. The equilibrium process was well described by the Langmuir isothermal model and the maximum adsorption capacity was found to be 23.6 mg/g. This is the first report on the design of imprinted polymer nanocomposites using Type II radical initiators under visible light in the presence of clay intercalated with hydrogen donor diazonium. The method is original, simple and efficient; it opens up new horizons in the general domain of clay/polymer nanocomposites
Pituitary stalk interruption syndrome on MRI: Case report
Key clinical message Pituitary stalk interruption syndrome (PSIS) is an antenatal anatomical defect characterized by pituitary insufficiency with symptomatology depending on associated hormonal deficits. Diagnosis is often delayed because many clinical findings. The gold standard for detection is pituitary MRI showing absence of pituitary stalk, anterior pituitary hypoplasia, and postpituitary ectopy. The treatment remains polyhormonal substitution. Abstract Pituitary stalk interruption syndrome (PSIS) is an antenatal anatomical defect. It is characterized by pituitary insufficiency with symptomatology depending on associated hormonal deficits. Diagnosis of PSIS is often delayed probably because of various clinical characteristics findings. Pituitary imaging abnormality is a specific indicator of hypopituitarism. The symptomatological triad associates a very thin or interrupted pituitary stalk, an ectopic or absent pituitary gland and hypoplasia of the anterior pituitary gland. The gold standard for detection is pituitary MRI. Some genetic factors are associated with the disease. The treatment remains polyhormonal substitution depending on the associated deficits. We reported the case of a 14âyearâold child with growth retardation in whom the biological workâup and pituitary MRI concluded that the diagnosis was PSIS with growth hormone deficiency. The treatment implemented was a recombinant growth hormone treatment. The immediate outcome was marked by a regression of symptoms
Facile diazonium modification of pomegranate peel biochar: A stupendous derived relationship between thermal and Raman analyses
There is an ever growing interest worldwide in the development of biochar from a large variety of agrowastes. This work contributes to the domain by tackling an agrowaste represented in pomegranate peels powder. The latter was activated by acid treatment and then pyrolyzed to generate low cost biochar. To enrich the surface of the resulting biochar, it was arylated with various in-situ generated diazonium salts of 4-aminobenzoic acid (H2N-C6H4-COOH), sulfanilic acid (H2N-C6H4-SO3H) and Azure A dye. The effect of diazonium nature and concentration on the arylation process was monitored essentially using thermal gravimetric analysis (TGA), and Raman spectroscopy. These techniques showed gradual changes in the arylation of biochar at low concentrations of 10-5, 10-4 and 10-3 M of 4-aminobenzoic acid. Interestingly, Azure A diazonium salt induces lower extent of surface modification, likely due to steric hindrance. One key feature of this work is the correlation between D/G Raman peak intensity ratio and the mass loading of the aryl groups. To the very best of our knowledge this is the first report ever on diazonium modification of agrowaste-derived biochar and opens new avenues for such carbon allotrope, i.e. surface arylation and applications