Mucosally induced immunological tolerance is an attractive strategy for preventing or treating illnesses resulting from untoward inf lammatory immune reactions against self-or non-self-antigens. Oral administration of relevant autoantigens and allergens has been reported to delay or suppress onset of clinical disease in a number of experimental autoimmune and allergic disorders. However, the approach often requires repeated feeding of large amounts of tolerogens over long periods and is only partly effective in animals already systemically sensitized to the ingested antigen such as in animals already harboring autoreactive T cells, and thus presumably also in humans with an autoimmune disease. We have recently shown that oral administration of microgram amounts of antigen coupled to cholera toxin B subunit (CTB), can effectively suppress systemic T cell reactivity in naive as well as in immune animals. We now report that feeding small amounts (2-20 g) of human insulin conjugated to CTB can effectively suppress beta cell destruction and clinical diabetes in adult nonobese diabetic (NOD) mice. The protective effect could be transferred by T cells from CTBinsulin-treated animals and was associated with reduced lesions of insulitis. Furthermore, adoptive co-transfer experiments involving injection of Thy-1,2 recipients with diabetogenic T cells from syngeneic mice and T cells from congenic Thy-1,1 mice fed with CTB-insulin demonstrated a selective recruitment of Thy-1,1 donor cells in the peripancreatic lymph nodes concomitant with reduced islet cell infiltration. These results suggest that protection against autoimmune diabetes can be achieved by feeding minute amounts of a pancreas islet cell autoantigen linked to CTB and appears to involve the selective migration and retention of protective T cells into lymphoid tissues draining the site of organ injury.
This is the largest study of chemotherapy in advanced SBA. Baseline PS and CEA and CA 19-9 levels were the main prognostic factors. FOLFOX seems to be the most effective platinum-based chemotherapy regimen.
Characterisation of the molecular structure of aquatic fulvic acids (FA) has been performed using a quadrupole time-of-flight (Q-TOF) mass spectrometer equipped with an electrospray ionisation interface. Molecular masses centred around 450 Da and sinusoidal spectral distributions have been obtained for all fulvic acids. Tandem mass spectrometry (MS/MS) experiments showed losses of 18 Da (H(2)O) and 44 Da (CO(2)), and possible molecular structures were determined for the first time to our knowledge. A methodology is reported for evaluating the average elemental composition of FA from high-resolution mass spectra by processing post-acquisition data calculations using molecular size distributions and atomic compositions of ions. The results are found to be consistent with elemental analysis data.
Time-resolved laser-induced fluorescence is a unique method for direct uranium speciation at low level in the framework of environmental studies. By varying pH and uranium concentration in the absence of carbonate ions and at fixed ionic strength, it was possible, together with free uranyl UO22+, to identify spectrally and temporally all the uranium-hydroxo complexes, namely, UO2OH+, UO2(OH)2, UO2(OH)3−, (UO2)2(OH)22+, (UO2)3(OH)5+, and (UO2)3(OH)7−.
Complexation studies of radionuclides (such as uranium) are important to perform in order to predict their migration behavior in natural systems. Time-resolved laserinduced fluorescence, which is a very selective and sensitive method for actinide and lanthanide analysis, is used to study the interactions between uranyl cation and hydroxide ions at low uranium concentration (0.4 pM). The principle of the study is based on time resolution and spectral convolution since free uranyl ion (UOz2+) and 6rst hydroxide complex give specific fluorescence spectra characterized by their spectral shift and fluorescence lifetime. Spectroscopic data (main fluorescence wavelengths, half-bandwidth, lifetime) for the first hydrolyzed complex U020Ht are obtained. From experimental spectra and time-resolved spectral convolution, the proportion of each species (free uranyl, complexed uranyl) can be estimated at different pH.
International audienceThe molecular environment of iodine in reference inorganic and organic compounds, and in dry humic and fulvic acids (HAs and FAs) extracted from subsurface and deep aquifers was probed by iodine L 3-edge X-ray absorption spectroscopy. The X-ray absorption near-edge structure (XANES) of iodine spectra from HAs and FAs resembled those of organic references and displayed structural features consistent with iodine forming covalent bonds with organic molecules. Simulation of XANES spectra by linear combination of reference spectra suggested the predominance of iodine forming covalent bonds to aromatic rings (aromatic-bound iodine). Comparison of extended X-ray absorption fine structure (EXAFS) spectra of reference and samples further showed that iodine was surrounded by carbon shells at distances comparables to those for references containing aromatic-bound iodine. Quantitative analysis of EXAFS spectra indicated that iodine was bound to about one carbon at a distance d (I–C) of 2.01(4)–2.04(9) A ˚ , which was comparable to the distances observed for aromatic-bound iodine in references (1.99(1)–2.07(6) A ˚), and significantly shorter than that observed for aliphatic-bound iodine (2.15(2)–2.16(2) A ˚). These results are in agreement with previous conclusions from X-ray photoelectron spectros-copy and from electrospray ionization mass spectrometry. These results collectively suggest that the aromatic-bound iodine is stable in the various aquifers of this study
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.