7 research outputs found
SMART geopolymers, an ERA-MIN project
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Seed-Mediated Hot-Injection Synthesis of Tiny Ag Nanocrystals on Nanoscale Solid Supports and Reaction Mechanism
Histological and Immunohistochemical Revision of Hepatocellular Adenomas: A Learning Experience
Light has been shed on the genotype/phenotype correlation in hepatocellular adenoma (HCA) recognizing HNF1α-inactivated HCA (H-HCA), inflammatory HCA (IHCA), and β-catenin-activated HCA (b-HCA). We reviewed retrospectively our surgical HCA series to learn how to recognize the different subtypes histopathologically and how to interpret adequately their immunohistochemical staining. From January 1992 to January 2012, 37 patients underwent surgical resection for HCA in our institution. Nine had H-HCA (25%) characterized by steatosis and loss of L-FABP expression; 20 had IHCA (55.5%) showing CRP and/or SAA expression, sinusoidal dilatation, and variable inflammation; and 1 patient had both H-HCA and IHCA. In 5 patients (14%), b-HCA with GS and β-catenin nuclear positivity was diagnosed, two already with hepatocellular carcinoma. Two cases (5.5%) remained unclassified. One of the b-HCA showed also the H-HCA histological and immunohistochemical characteristics suggesting a subgroup of β-catenin-activated/HNF1α-inactivated HCA, another b-HCA exhibited the IHCA histological and immunohistochemical characteristics suggesting a subgroup of β-catenin-activated/inflammatory HCA. Interestingly, three patients had underlying vascular abnormalities. Using the recently published criteria enabled us to classify histopathologically our retrospective HCA surgical series with accurate recognition of b-HCA for which we confirm the higher risk of malignant transformation. We also underlined the association between HCA and vascular abnormalities
Congenital hyperinsulinism and mosaic abnormalities of the ploidy
BACKGROUND: Congenital hyperinsulinism and Beckwith-Wiedemann syndrome both lead to beta islet hyperplasia and neonatal hypoglycaemia. They may be related to complex genetic/epigenetic abnormalities of the imprinted 11p15 region. The possibility of common pathophysiological determinants has not been thoroughly investigated. OBJECTIVE: To report abnormalities of the ploidy in two unrelated patients with congenital hyperinsulinism. METHODS: Two patients with severe congenital hyperinsulinism, one overlapping with Beckwith-Wiedemann syndrome, had pancreatic histology, ex vivo potassium channel electrophysiological studies, and mutation detection of the encoding genes. The parental genetic contribution was explored using genome-wide polymorphism, fluorescent in situ hybridisation (FISH), and blood group typing studies. RESULTS: Histological findings diverged from those described in focal congenital hyperinsulinism or Beckwith-Wiedemann syndrome. No potassium channel dysfunction and no mutation of its encoding genes (SUR1, KIR6.2) were detected. In patient 1 with congenital hyperinsulinism and Beckwith-Wiedemann syndrome, paternal isodisomy for the whole haploid set was homogeneous in the pancreatic lesion, and mosaic in the leucocytes and skin fibroblasts (hemihypertrophic segment). Blood group typing confirmed the presence of two erythroid populations (bi-parental v paternal only contribution). Patient 2 had two pancreatic lesions, both revealing triploidy with paternal heterodisomy. Karyotype and FISH analyses done on the fibroblasts and leucocytes of both patients were unremarkable (diploidy). CONCLUSIONS: Diploid (biparental/paternal-only) mosaicism and diploid/triploid mosaicism were present in two distinct patients with congenital hyperinsulinism. These chromosomal abnormalities led to paternal disomy for the whole haploid set in pancreatic lesions (with isodisomy or heterodisomy), thereby extending the range and complexity of the mechanisms underlying congenital hyperinsulinism, associated or not with Beckwith-Wiedemann syndrome
Synthesis, growth mechanism, and photocatalytic activity of Zinc oxide nanostructures: porous microparticles versus nonporous nanoparticles
Effect of cationic and anionic surfactants on the application of calcium carbonate nanoparticles in paper coating
Modification of calcium carbonate particles with surfactant significantly improves the properties of the calcium carbonate coating on paper. In this study, unmodified and CTAB (hexadecyltetramethylammonium bromide)- and oleate-modified calcium carbonate nanoparticles were prepared using the wet carbonation technique for paper coating. CTAB (cationic surfactant) and sodium oleate (anionic surfactant) were used to modify the size, morphology, and surface properties of the precipitated nanoparticles. The obtained particles were characterized using X-ray diffraction (XRD), Fourier transform infrared (FT-IR) spectroscopy, zeta potential measurements, thermal gravimetric analysis (TGA), and transmission electron microscopy (TEM). Coating colors were formulated from the prepared unmodified and modified calcium carbonates and examined by creating a thin coating layer on reference paper. The effect of calcium carbonate particle size and surface modification on paper properties, such as coating thickness, coating weight, surface roughness, air permeability, brightness, whiteness, opacity, and hydrophobicity, were investigated and compared with commercial ground (GCC) calcium carbonate-coated papers. The results show that the obtained calcium carbonate nanoparticles are in the calcite phase. The morphology of the prepared calcium carbonate nanoparticles is rhombohedral, and the average particle diameter is less than 100 nm. Compared to commercial GCC, the use of unmodified and CTAB- and oleate-modified calcium carbonate nanoparticles in paper coating improves the properties of paper. The highest measured paper properties were observed for paper coated with oleate-modifed nanoparticles, where an increase in smoothness (decrease in paper roughness) (+23%), brightness (+1.3%), whiteness (+2.8%), and opacity (+2.3%) and a decrease in air permeability (-26%) was obtained with 25% less coat weight. The water contact angle at a drop age time of 10 min was about 112 for the paper coated with oleate-modified nanoparticles and 42 for paper coated with CTAB-modified nanoparticles compared to 104 for GCC-coated paper. © 2014 American Chemical Society.SCOPUS: ar.jSCOPUS: ar.jinfo:eu-repo/semantics/publishe