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Under a temperature gradient, the direction of thermodiffusion of charged γ-Fe2O3 nanoparticles (NPs) depends on the nature of the counter-ions present in the dispersion, resulting in either a positive or negative Soret coefficient. Various counter-ions are probed in finely tuned and well characterized dispersions of citrate-coated NPs at comparable concentrations of free ionic species. The Soret coefficient ST is measured in stationary conditions together with the mass-diffusion coefficient Dm using a forced Rayleigh scattering method. The strong interparticle repulsion, determined by SAXS, is also attested by the increase of Dm with NP volume fraction Φ. The Φ-dependence of ST is analyzed in terms of thermophoretic and thermoelectric contributions of the various ionic species. The obtained single-particle thermophoretic contribution of the NPs (the Eastman entropy of transfer sNP) varies linearly with the entropy of transfer of the counter-ions. This is understood in terms of electrostatic contribution and of hydration of the ionic shell surrounding the NPs. Two aqueous dispersions, respectively, with ST > 0 and with ST < 0 are then probed under an applied field H[combining right harpoon above], and an anisotropy of Dm and of ST is induced while the in-field system remains monophasic. Whatever the H[combining right harpoon above]-direction (parallel or perpendicular to the gradients and ), the Soret coefficient is modulated keeping the same sign as in zero applied field. In-field experimental determinations are well described using a mean field model of the interparticle magnetic interaction.
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Thermodiffusion of different ferrite nanoparticles (NPs), â¼10 nm in diameter, is explored in tailor-made aqueous dispersions stabilized by electrostatic interparticle interactions. In the dispersions, electrosteric repulsion is the dominant force, which is tuned by an osmotic-stress technique, i.e. controlling of osmotic pressure Π, pH and ionic strength. It is then possible to map Π and the NPs' osmotic compressibility χ in the dispersion with a Carnahan-Starling formalism of effective hard spheres (larger than the NPs' core). The NPs are here dispersed with two different surface ionic species, either at pH â¼ 2 or 7, leading to a surface charge, either positive or negative. Their Ludwig-Soret ST coefficient together with their mass diffusion Dm coefficient are determined experimentally by forced Rayleigh scattering. All probed NPs display a thermophilic behavior (ST < 0) regardless of the ionic species used to cover the surface. We determine the NPs' Eastman entropy of transfer and the Seebeck (thermoelectric) contribution to the measured Ludwig-Soret coefficient in these ionic dispersions. The NPs' Eastman entropy of transfer sNP is interpreted through the electrostatic and hydration contributions of the ionic shell surrounding the NPs.
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BACKGROUND: Most umbilical tumors are diagnosed as benign tumors, umbilical metastases of abdominal and pelvic tumors, or Sister Marie Joseph nodule. Herein, we report a case of cutaneous umbilical endometriosis mistaken for a keloid. PATIENTS AND METHODS: A young black woman aged 26 consulted for a painful umbilical tumefaction. She had noted the appearance of a nodule of the umbilicus 10 months ago with bleeding during her menstrual periods. Skin examination revealed a firm and painful umbilical nodule 2.5cm in diameter. She was treated with corticosteroid injections for one month for umbilical keloid. Given that the symptoms recurred regularly at the time of menstruation, we suspected umbilical endometriosis. This diagnosis was finally confirmed by histopathological examination and hormone therapy was instituted on gynecological advice before scheduled surgical excision. CONCLUSION: In a setting of an umbilical tumor simulating a keloid associated with cyclical symptoms in a black woman, the diagnosis of umbilical endometriosis should not be overlooked by the dermatologist.
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Neoplasias Abdominales/patología , Endometriosis/patología , Queloide/patología , Ombligo , Adulto , Población Negra , Diagnóstico Diferencial , Femenino , HumanosRESUMEN
The Seebeck and Soret coefficients of ionically stabilized suspension of maghemite nanoparticles in dimethyl sulfoxide are experimentally studied as a function of nanoparticle volume fraction. In the presence of a temperature gradient, the charged colloidal nanoparticles experience both thermal drift due to their interactions with the solvent and electric forces proportional to the internal thermoelectric field. The resulting thermodiffusion of nanoparticles is observed through forced Rayleigh scattering measurements, while the thermoelectric field is accessed through voltage measurements in a thermocell. Both techniques provide independent estimates of nanoparticle's entropy of transfer as high as 82 meV K(-1). Such a property may be used to improve the thermoelectric coefficients in liquid thermocells.
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INTRODUCTION: Mantle cell lymphoma is a rare lymphoma of the gastrointestinal tract that may present as multiple lymphomatous polyposis. We report a case of lymphomatous polyposis with a review of the literature. CASE REPORT: A 56-year-old man of Black ethnicity and Ivorian nationality with no relevant past medical history, consulted for a sudden onset symptoms of gastrointestinal obstruction, which evolved over 2 days. Macroscopic examination revealed the presence of multiple polyploid formations of the colonic mucosa. Histology showed diffuse lymphomatous proliferation of submucosa consisting off small lymphoid cells with a hyperchromatic crenelated nucleus, suggesting lymphomatous polyposis. Immunohistochemical examination showed expression by the tumor cells of antibodies to CD20, CD5, Bcl2, and cyclin D1. They did not express antibodies to CD10 and CD23. The Ki67 proliferation index was 25%. We have thus retained the diagnosis of mantle cell lymphomatous polyposis. CONCLUSION: Multiple lymphomatous polyposis is a rare entity characterized by the presence of numerous gastrointestinal polyploid lesions sometimes involving several segments of the gastrointestinal tract. Typical lymphoma presenting as lymphomatous polyposis is mantle cell lymphoma; although, other tumors may have this aspect.
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Linfoma de Células del Manto , Humanos , Linfoma de Células del Manto/patología , Linfoma de Células del Manto/diagnóstico , Masculino , Persona de Mediana Edad , Neoplasias del Colon/patología , Pólipos del Colon/patologíaRESUMEN
A total of 418 healers have been interviewed in Guinea, a coastal country of West Africa, ranging between 7 degrees 30 and 12 degrees 30 of northern latitude and 8 degrees and 15 degrees of western longitude. Plant species used by the local inhabitants to treat infectious diseases were identified using ethnobotanical, ethnographic and taxonomic methods. During these investigations, 218 plants were registered, of which the following were the most frequently used: Erythrina senegalensis, Bridelia ferruginea, Crossopteryx febrifuga, Ximenia americana, Annona senegalensis, Cochlospermum tinctorium, Cochlospermum planchonii, Lantana camara, Costus afer, Psidium guajava, Terminalia glaucescens, Uapaca somon and Swartzia madagascariensis. Most plants, and especially the leaves, were essentially used as a decoction. In order to assess antibacterial activity, 190 recipes were prepared and biologically tested, among which six showed activity (minimal inhibitory concentration<125 microg/ml) against Bacillus cereus, Mycobacterium fortuitum, Staphylococcus aureus, or Candida albicans, i.e., Entada africana, Chlorophora regia, Erythrina senegalensis, Harrisonia abyssinica, Uvaria tomentosa, and a mixture of six plants consisting of Swartzia madagascariensis, Isoberlinia doka, Annona senegalensis, Gardenia ternifolia, Terminalia glaucescens and Erythrina senegalensis.
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Antibacterianos/farmacología , Medicinas Tradicionales Africanas , Extractos Vegetales/farmacología , Plantas Medicinales/química , Adulto , Anciano , Antibacterianos/aislamiento & purificación , Recolección de Datos , Femenino , Guinea , Conocimientos, Actitudes y Práctica en Salud , Humanos , Masculino , Pruebas de Sensibilidad Microbiana , Persona de Mediana Edad , Extractos Vegetales/aislamiento & purificación , Estructuras de las PlantasRESUMEN
ETHNOPHARMACOLOGICAL RELEVANCE: The recent outbreak of Ebola virus infections has mostly remained confined to the West African countries Guinea-Conakry, Sierra-Leone and Liberia. Due to intense national and international mobilizations, a significant reduction in Ebola virus transmission has been recorded. While international efforts focus on new vaccines, medicines and diagnostics, no coherent national or international approach exists to integrate the potential of the traditional health practitioners (THPs) in the management of infectious diseases epidemics. Nevertheless, the first contact of most of the Ebola infected patients is with the THPs since the symptoms are similar to those of common traditionally treated diseases or symptoms such as malaria, hemorrhagic syndrome, typhoid or other gastrointestinal diseases, fever and vomiting. MATERIALS AND METHODS: In an ethnomedical survey conducted in the 4 main Guinean regions contacts were established with a total of 113 THPs. The socio-demographic characteristics, the professional status and the traditional perception of Ebola Virus Disease (EVD) were recorded. RESULTS: The traditional treatment of the main symptoms was based on 47 vegetal recipes which were focused on the treatment of diarrhea (22 recipes), fever (22 recipes), vomiting (2 recipes), external antiseptic (2 recipes), hemorrhagic syndrome (2 recipes), convulsion and dysentery (one recipe each). An ethnobotanical survey led to the collection of 54 plant species from which 44 identified belonging to 26 families. The most represented families were Euphorbiaceae, Caesalpiniaceae and Rubiaceae. Literature data on the twelve most cited plant species tends to corroborate their traditional use and to highlight their pharmacological potential. CONCLUSIONS: It is worth to document all available knowledge on the traditional management of EVD-like symptoms in order to evaluate systematically the anti-Ebola potential of Guinean plant species.
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Personal de Salud , Fiebre Hemorrágica Ebola/tratamiento farmacológico , Medicina Tradicional , Adulto , Anciano , Anciano de 80 o más Años , Brotes de Enfermedades/prevención & control , Ebolavirus , Etnobotánica , Femenino , Guinea , Conocimientos, Actitudes y Práctica en Salud , Fiebre Hemorrágica Ebola/epidemiología , Fiebre Hemorrágica Ebola/prevención & control , Humanos , Masculino , Persona de Mediana EdadRESUMEN
INTRODUCTION: Mucormycosis is a deep mycosis which has been spreading out in recent years. It is still poorly understood and poorly described in sub-Saharan Africa. The authors report a case of sinonasal localization, of fatal evolution and late diagnosis in a young child. OBSERVATION: It is about a 13-year-old child suffering from chronic rhinosinus syndrome for two years. He was observed in stomatology for a necrotic velar ulceration that have occurred for three months. The clinical, radiological and histological explorations were in favor of a sinonasal mucormycosis. The administration of amphotericin B and the surgical treatment did not slow down the fatal evolution. CONCLUSION: Mucormycosis should not be dealt with any diagnostic error and no therapeutic improvisation. It has to be thought about when dealing with a rhinosinusal syndrome with cleft ulceration.
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Mucormicosis/diagnóstico , Úlceras Bucales/microbiología , Paladar Blando/patología , Rinitis/microbiología , Adolescente , Diagnóstico Diferencial , Humanos , Masculino , Mucormicosis/microbiología , Necrosis/complicaciones , Necrosis/diagnóstico , Necrosis/microbiología , Úlceras Bucales/diagnóstico , Úlceras Bucales/patología , Paladar Blando/microbiología , Rinitis/complicaciones , Sinusitis/complicaciones , Sinusitis/microbiologíaRESUMEN
We report an exceptional association of metacarpal and clavicular tuberculosis in a two-year-old child with SAFA2 sickle cell disease. We emphasize the role of imaging (X-ray and CT scan) in this work. The definitive diagnosis is confirmed by the pathological examination of biopsy samples. This location should be known in endemic tuberculosis areas.
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Clavícula/patología , Huesos del Metacarpo/patología , Tuberculosis Osteoarticular/diagnóstico , Antituberculosos/uso terapéutico , Preescolar , Clavícula/diagnóstico por imagen , Humanos , Masculino , Huesos del Metacarpo/diagnóstico por imagen , Tomografía Computarizada por Rayos X , Tuberculosis Osteoarticular/diagnóstico por imagen , Tuberculosis Osteoarticular/tratamiento farmacológicoRESUMEN
Our main objective consists in evaluating the frequency of digestive signs and digestive opportunistic infections in AIDS patients with diarrhea. The prospective study occurred from January 1997 to July 1998 in Bamako hospitals. The patients underwent a clinical examination, blood and stools tests, and sometimes upper digestive endoscopy. Among 434 cases of AIDS, 426 patients (98%) had at least one digestive sign. The main digestive signs were diarrhea (80.1%), abdominal pains (62.2%), vomiting (47.2%) and dysphagea (36.6%). Isospora belli and Cryptosporidium parvum have been pointed up in respectively 9% and 16.3% of examined specimen. Echerichia coli was found in 8.6% of stool cultures and in 2.9% in the case of Salmonella Arizonae. Twenty cases of Kaposi's sarcoma were diagnosed and mycosis was found in 71.9% of patients. In conclusion, digestive change is a constant phenomenon in AIDS patients. Patients survival could be improved by early management, improvement of diagnosis and provisioning of medicines.