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Oligomer resins and process oils are indispensable for rubber technology in order to achieve high-performance tyres on wet roads and ultralow energy consumption with acceptable manufacturability. This study investigates the solubility of oligomer resins, oils and elastomers using differential scanning calorimetry and describes its implication on rubber compound hysteresis loss. Owing to the configurational entropy of mixing, resin molecular weight strongly influences miscibility within binary resin/oil, ternary resin/oil/elastomer and filled rubber compounds. Similarity of chemical structure plays a role in miscibility linked to enthalpic effects. Among Hansen solubility parameters, the polar component correctly ranks the compatibility of resins with oils and elastomers. It has been shown that increased solubility among the resin–oil–elastomer system provides better balance of predicted rolling resistance and wet grip of tread compounds. Therefore, optimisation of rubber properties relies on the adequate selective use of process oils and resins according to their chemical structure and molecular weight. [ABSTRACT FROM AUTHOR]

Medium-chain fatty acids (MCFAs) are considered to be interesting energy sources for dogs affected by chronic enteropathies (CE). This study analyzed the clinical scores, fecal microbiota, and metabolomes of 18 CE dogs fed a home-cooked diet (HCD) supplemented with virgin coconut oil (VCO), a source of MCFA, at 10% of metabolizable energy (HCD + VCO). The dogs were clinically evaluated with the Canine Chronic Enteropathy Activity Index (CCECAI) before and at the end of study. Fecal samples were collected at baseline, after 7 days of HCD, and after 30 days of HCD + VCO, for fecal score (FS) assessment, microbial analysis, and determination of bile acids (BA), sterols, and fatty acids (FA). The dogs responded positively to diet change, as shown by the CCECAI improvement ( p = 0.001); HCD reduced fecal fat excretion and HCD + VCO improved FS ( p < 0.001), even though an increase in fecal moisture occurred due to HCD ( p = 0.001). HCD modified fecal FA (C6:0: +79%, C14:0: +74%, C20:0: +43%, C22:0: +58%, C24:0: +47%, C18:3n-3: +106%, C20:4n-6: +56%, and monounsaturated FA (MUFA): -23%, p < 0.05) and sterol profile (coprostanol: -27%, sitostanol: -86%, p < 0.01). VCO increased ( p < 0.05) fecal total saturated FA (SFA: +28%, C14:0: +142%, C16:0 +21%, C22:0 +33%) and selected MCFAs (+162%; C10:0 +183%, C12:0 +600%), while reducing ( p < 0.05) total MUFA (-29%), polyunsaturated FA (-26%), campesterol (-56%) and phyto-/zoosterols ratio (0.93:1 vs. 0.36:1). The median dysbiosis index was <0 and, together with fecal BA, was not significantly affected by HCD nor by VCO. The HCD diet increased total fecal bacteria ( p = 0.005) and the abundance of Fusobacterium spp. ( p = 0.028). This study confirmed that clinical signs, and to a lesser extent fecal microbiota and metabolome, are positively influenced by HCD in CE dogs. Moreover, it has been shown that fecal proportions of MCFA increased when MCFAs were supplemented in those dogs. The present results emphasize the need for future studies to better understand the intestinal absorptive mechanism of MCFA in dogs.

Microalgae are a source of bioactive compounds having recently been studied for their possible application as health-promoting ingredients. The aim of the study was to evaluate in an in vitro canine gut model the effects of four microalgae, Arthrospira platensis (AP), Haematococcus pluvialis (HP), Phaeodactylum tricornutum (PT) and Chlorella vulgaris (CV), on some fecal microbial populations and metabolites. The four microalgae were subjected to an in vitro digestion procedure, and subsequently, the digested biomass underwent colonic in vitro fermentation. After 6 h of incubation, PT increased propionate (+36%) and butyrate (+24%), and decreased total BCFA (-47%), isobutyrate (-52%) and isovalerate (-43%) and C. hiranonis (-0.46 log10 copies/75 ng DNA). After 24 h, PT increased propionate (+21%) and isovalerate (+10%), and decreased the abundance of Turicibacter spp. (7.18 vs. 6.69 and 6.56 log10 copies/75 ng DNA for CTRL vs. PT, respectively); moreover, after 24 h, CV decreased C. coccoides (-1.12 log10 copies/75 ng DNA) and Enterococcus spp. (-0.37 log10 copies/75 ng DNA). In conclusion, the microbial saccharolytic activities and the shift in fecal bacterial composition were less pronounced than expected, based on current literature. This study should be considered as a preliminary assessment, and future investigations are required to better understand the role of microalgae in canine nutrition.

Transfusion-dependent patients typically develop iron-induced cardiomyopathy, liver disease, and endocrine complications. We aimed to estimate the incidence of endocrine disorders in transfusiondependent thalassemia (TDT) patients during long-term iron-chelation therapy with deferasirox (DFX). We developed a multi-center follow-up study of 426 TDT patients treated with once-daily DFX for a median duration of 8 years, up to 18.5 years. At baseline, 118, 121, and 187 patients had 0, 1, or ≥2 endocrine diseases respectively. 104 additional endocrine diseases were developed during the follow-up. The overall risk of developing a new endocrine complication within 5 years was 9.7% (95% Confidence Interval [CI]: 6.3-13.1). Multiple Cox regression analysis identified three key predictors: age showed a positive log-linear effect (adjusted hazard ratio [HR] for 50% increase 1.2, 95% CI: 1.1-1.3, P=0.005), the serum concentration of thyrotropin showed a positive linear effect (adjusted HR for 1 mIU/L increase 1.3, 95% CI: 1.1-1.4, P<0.001) regardless the kind of disease incident, while the number of previous endocrine diseases showed a negative linear effect: the higher the number of diseases at baseline the lower the chance of developing further diseasess (adjusted HR for unit increase 0.5, 95% CI: 0.4-0.7, P<0.001). Age and thyrotropin had similar effect sizes across the categories of baseline diseases. The administration of levothyroxine as a covariate did not change the estimates. Although in DFX-treated TDT patients the risk of developing an endocrine complication is generally lower than the previously reported risk, there is considerable risk variation and the burden of these complications remains high. We developed a simple risk score chart enabling clinicians to estimate their patients' risk. Future research will look at increasing the amount of variation explained from our model and testing further clinical and laboratory predictors, including the assessment of direct endocrine magnetic resonance imaging.

Endocrine complications of haemochromatosis and heart failure mostly affect morbidity and mortality in polytransfused patients. This study analyzes endocrine dysfunctions and the impact of GH-IGF-1 axis alteration on cardiac performance in a population of 31 patients. A retrospective study on 31 Caucasian polytransfused outpatients, 27 adults and 4 pediatric, residing in Apulia, Italy, followed from 2005 to 2016, was conducted. Patients underwent basal and dynamic hormonal evaluation. GHRH plus arginine test was performed in 21 patients (19 adults and 2 children). Among them, 9 patients were affected by left ventricle diastolic dysfunction and/or atrial or ventricular dilatation (HD group) and 12 patients did not have cardiovascular disease (non-HD group). Twenty-nine out of 31 patients (94%) had at least one endocrinopathy. We found severe or mild GH deficit (GHD) in all HD patients versus 3 patients in the non-HD group (p=0.001). Mean IGF-1 levels were significantly lower in the HD group than in non-HD subjects (53±30 versus 122±91 μ g/L, p=0.04). Our study confirms the need to perform a dynamic evaluation of the GH-IGF1 axis in polytransfused patients, especially when heart dysfunction emerges. An intervention study with GH replacement therapy in a larger randomized adult population will clarify the role of GH/IGF axis on cardiovascular outcomes in this patient population.