Feline low-grade alimentary lymphoma: an emerging entity and a potential animal model for human disease

Background: Low-grade alimentary lymphoma (LGAL) is characterised by the infiltration of neoplastic T-lymphocytes, typically in the small intestine. The incidence of LGAL has increased over the last ten years and it is now the most frequent digestive neoplasia in cats and comprises 60 to 75% of gastrointestinal lymphoma cases. Given that LGAL shares common clinical, paraclinical and ultrasonographic features with inflammatory bowel diseases, establishing a diagnosis is challenging. A review was designed to summarise current knowledge of the pathogenesis, diagnosis, prognosis and treatment of feline LGAL. Electronic searches of PubMed and Science Direct were carried out without date or language restrictions. Results: A total of 176 peer-reviewed documents were identified and most of which were published in the last twenty years. 130 studies were found from the veterinary literature and 46 from the human medicine literature. Heterogeneity of study designs and outcome measures made meta-analysis inappropriate. The pathophysiology of feline LGAL still needs to be elucidated, not least the putative roles of infectious agents, environmental factors as well as genetic events. The most common therapeutic strategy is combination treatment with prednisolone and chlorambucil, and prolonged remission can often be achieved. Developments in immunohistochemical analysis and clonality testing have improved the confidence of clinicians in obtaining a correct diagnosis between LGAL and IBD. The condition shares similarities with some diseases in humans, especially human indolent T-cell lymphoproliferative disorder of the gastrointestinal tract. Conclusions: The pathophysiology of feline LGAL still needs to be elucidated and prospective studies as well as standardisation of therapeutic strategies are needed. A combination of conventional histopathology and immunohistochemistry remains the current gold-standard test, but clinicians should be cautious about reclassifying cats previously diagnosed with IBD to lymphoma on the basis of clonality testing. Importantly, feline LGAL could be considered to be a potential animal model for indolent digestive T-cell lymphoproliferative disorder, a rare condition in human medicine

Hydroxyl environments in zeolites probed by deuterium solid-state MAS NMR combined with IR spectroscopy

International audienceHigh-resolution deuterium solid-state MAS NMR combined with IR spectroscopy reveals the electric environments of different hydroxyls (silanols and Brønsted) in FAU type zeolites

Detection of CO2 and O2 by iron loaded LTL zeolite films

International audienceDetection of oxygen and carbon dioxide is important in the field of chemical and biosensors for atmosphere and biosystem monitoring and fermentation processes. The present study reports on the preparation of zeolite films doped with iron nanoparticles for detection of CO2 and O2 in gas phase. Pure nanosized LTL type zeolite with monomodal particle size distribution loaded with iron (Fe-LTL) was prepared under hydrothermal condition from colloidal precursor suspensions. The zeolite was loaded with iron to different levels by ion exchange. The Fe-LTL suspensions were used for preparation of thin films on silicon wafers via spin coating method. The reduction of the iron in the zeolite films was carried out under H2 flow (50% H2 in Ar) at 300 °C. The presence of iron nanoparticles is proved by in situ ultra-violet-visible spectroscopy. The properties of the films including surface roughness, thickness, porosity, and mechanical stability were studied. In addition, the loading and distribution of iron in the zeolite films were investigated. The Fe-LTL zeolite films were used to detect O2 and CO2 in a concentration dependent mode, followed by IR spectroscopy. The changes in the IR bands at 855 and 642 cm–1 (Fe‒O‒H and Fe‒O bending vibrations) and at 2363 and 2333 cm–1 (CO2 asymmetric stretching) corresponding to the presence of O2 and CO2, respectively, were evaluated. The response to O2 and CO2 was instant, which was attributed to great accessibility of the iron in the nanosized zeolite crystals. The saturation of the Fe-LTL films with CO2 and O2 at each concentration was reached within less than a minute. The Fe-LTL films detected both oxygen and carbon dioxide in contrast, to the pure LTL zeolite film

Detection of CO2 and O2 by iron loaded LTL zeolite films

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Altering the atomic order in nanosized CHA zeolites by post-synthetic silylation treatment

In this work, we present a new post-synthetic hydrothermal approach leading to simultaneous dealumination and silylation of zeolite nanocrystals. Starting from a nanosized chabazite (CHA) type zeolite with a Si/Al ratio equal to 2, a set of samples with Si/Al ratios up to 4 were obtained by altering the acidity and concentration of the added silica modifier during the post-synthesis treatment leading to concurrent dealumination and silylation. The effect of the acidity during the post-synthetic silylation treatment at different pH of 1.0 to 8.5 at a constant silicon concentration was investigated. The nanosized CHA samples were characterized in details by FTIR and NMR spectroscopy (1 H, 29 Si, 27 Al), X-ray diffraction and thermogravimetric analyses. The post-synthesis approach reported here can be applied to other zeolite types for fine tuning of their structural features including type and location of Tatoms, silanol sites and active sites

The preparation of hierarchical SAPO-34 crystals via post-synthesis fluoride etching

Accessed by 03/2016International audienc

CO 2 adsorption behaviour of nanosized CHA zeolites synthesised in the presence of barium or calcium cations

International audienceAlkaline-earth metal cations impact the rate of crystallisation and the adsorption of N 2 and CO 2 on nanosized chabazite zeolites. In this study, either calcium or barium was added to precursor mixtures containing alkali-metal cations (Na + , K + , Cs +) to prepare chabazite (labelled Ca-CHA and Ba-CHA), and were compared to a reference sample (Ref-CHA) synthesized using exclusively Na + , K + , and Cs +. Partial substitution of the Na + and the pore-blocking Cs + extra-framework cations was observed for Ca-CHA depending on the molar ratio of K 2 O used in the synthesis, while a change to the amount of Na + cations only was observed for Ba-CHA. The type of alkaline-earth metal cation affects the crystallisation rate; slower in the presence of Ca 2+ (10 h to full crystallinity) and similar rates in the presence of Ba 2+ (4 h to full crystallinity); the crystallite size and morphology remained similar. The presence of Ca 2+ or Ba 2+ extra-framework cations leads to N 2 uptake values of 290 and 169 mmol•g-1 (−196 °C, 100 kPa), respectively, while at low CO 2 pressure (< 1 kPa, 25 °C), the physisorbed CO 2 capacity for Ref-CHA, Ca-CHA, and Ba-CHA zeolites is 0.63, 0.66, and 0.59 mmol•g-1 , respectively. Interestingly, an opposite effect is observed for the amount of chemisorbed CO 2 species

Quantification of Lewis acid sites in 3D and 2D TS-1 zeolites: FTIR spectroscopic study

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A Facile Route toward the Increase of Oxygen Content in Nanosized Zeolite by Insertion of Cerium and Fluorinated Compounds

CERVOXY COLLInternational audienc

In situ and post-synthesis control of physicochemical properties of FER-type crystals

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