Cytokine and Chemokine Concentrations as Biomarkers of Feline Mycobacteriosis

Abstract Mycobacteriosis is an emerging zoonotic disease of domestic cats and timely, accurate diagnosis is currently challenging. To identify differential cytokine/chemokine concentrations in serum/plasma of cats, which could be diagnostic biomarkers of infection we analysed plasma/serum from 116 mycobacteria-infected cats, 16 healthy controls and six cats hospitalised for unrelated reasons was analysed using the Milliplex MAP Feline Cytokine Magnetic Bead multiplex assay. Three cytokines; sFAS, IL-13 and IL-4 were reduced while seven; GM-CSF, IL-2, PDGF-BB, IL-8, KC, RANTES and TNF-α were elevated in mycobacteria-infected cats compared to healthy controls. However, IL-8 and KC concentrations were not significantly different from cats hospitalised for other reasons. Elevations in TNF-α and PDGF-BB may have potential to identify M. bovis and M. microti infected cats specifically while GM-CSF, IL-2 and FLT3L were increased in MTBC infected cats. This study demonstrates potential use of feline tuberculosis as a spontaneously occurring model of this significant human disease. Cytokine profiling has clear diagnostic potential for mycobacteriosis of cats and could be used discriminate tuberculous from non-tuberculous disease to rapidly inform on zoonotic risk. Future work should focus on the in-field utility of these findings to establish diagnostic sensitivity and specificity of these markers

Viscosity of poly(ethyleneglycol) 200 [PEG 200] saturated with supercritical carbon dioxide

The article presents viscosity measurements on mixtures of poly(ethyleneglycol) 200 (PEG 200) saturated with supercritical CO2, along three isotherms, at approximately 313K, 333K and 348K, and pressures up to 25 MPa. The measurements have been performed with a previously described vibrating wire instrument. The results show a steep initial viscosity decrease with increasing pressure of CO2, followed by a flatter zone, extending up to 25 MPa. This behavior, which is quantitatively temperature dependent, seems to be closely related to the solubility of CO2 as a function of pressure. The experimental method for the determination of the viscosity requires the density of the samples. For this purpose, the density data for the mixtures were calculated from phase equilibrium studies by Gourgouillon and Nunes da Ponte, using the Sanchez-Lacombe equation of state. The measured viscosity data for CO2 saturated PEG 200 solutions were then correlated using the Kelly-Bueche theoryinfo:eu-repo/semantics/publishedVersio

In-Situ IR spectroscopy and ab initio calculations to study polymer swelling by supercritical CO2

The CO2 sorption and polymer swelling of hydroxytelechelic polybutadiene (HTPB) and poly(ethylene glycol) (PEG) have been investigated as a function of temperature and CO2 pressure by combining in situ near-infrared spectroscopy with molecular modeling. The results reported here for the PEG−CO2 system are in a very good agreement with literature data hence validating our experimental procedure. It has been found that CO2 sorption and swelling effect is more important for PEG than for HTPB. For both polymers, an increase of temperature leads to a strong decrease of both the CO2 sorption and swelling. In order to identify at a molecular level the nature and strength of intermolecular interaction occurring between CO2 and the polymers, ab initio calculations have been performed on model structures, representative of the main functional group of the polymer, and their complex with CO2. Trans-3-hexene (3-Hex), propyl methyl ether (PME) and methoxytrimethylsilane (MTMS) have been selected to mimic the functional groups of HTPB, PEG and polydimethyl siloxane (PDMS), respectively. The last system has been chosen since previous works on the swelling of PDMS by high pressure CO2 have revealed the high ability of CO2 to swell both uncrosslinked and crosslinked PDMS. The calculated stabilization energies of the MTMS−CO2, PME−CO2, and 3-Hex−CO2 dimers indicate that CO2 interacts specifically with the three moieties through a Lewis acid−Lewis base type of interaction with the energies displaying the following order: E(MTMS−CO2) = −3.59 > E(PME−CO2) = −3.43 > E(3-Hex−CO2) = −2.5 kcal/mol. Since the solubility of CO2 in the corresponding homopolymers follows the same order, it is evidenced that the stronger the interaction between CO2 and the polymer, the higher the CO2 sorption. Therefore, even if one cannot exclude the influence of free volume and chain flexibility of the polymer, it appears that the solubility of CO2 in the polymer is predominantly governed by the interaction between CO2 and the polymer. Although the same trend is observed for the swelling of the polymer as a function of the CO2 pressure, we have found that for a given value of CO2 sorption, the swelling of the polymer depends on its nature, meaning that the swelling is not only governed by the CO2−polymer interaction but also by other intrinsic properties of the polymer