Emulsion formation and stabilization by biomolecules: the leading role of cellulose

Emulsion stabilization by native cellulose has been mainly hampered because of its insolubility in water. Chemical modification is normally needed to obtain water-soluble cellulose derivatives. These modified celluloses have been widely used for a range of applications by the food, cosmetic, pharmaceutic, paint and construction industries. In most cases, the modified celluloses are used as rheology modifiers (thickeners) or as emulsifying agents. In the last decade, the structural features of cellulose have been revisited, with particular focus on its structural anisotropy (amphiphilicity) and the molecular interactions leading to its resistance to dissolution. The amphiphilic behavior of native cellulose is evidenced by its capacity to adsorb at the interface between oil and aqueous solvent solutions, thus being capable of stabilizing emulsions. In this overview, the fundamentals of emulsion formation and stabilization by biomolecules are briefly revisited before different aspects around the emerging role of cellulose as emulsion stabilizer are addressed in detail. Particular focus is given to systems stabilized by native cellulose, either molecularly-dissolved or not (Pickering-like effect).Financially support by the Portuguese Foundation for Science and Technology, FCT, via the projects PTDC/AGR-TEC/4814/2014, PTDC/ASP-SIL/30619/2017 and researcher grant IF/01005/2014. RISE Research Institutes of Sweden AB and PERFORM, a competence platform in Formulation Science at RISE, are acknowledged for additional financing. This research has been supported by Treesearch.se.info:eu-repo/semantics/publishedVersio

Anaerobic bacteria commonly colonize the lower airways of intubated ICU patients

ObjectivesTo investigate respiratory tract colonization by aerobic and anaerobic bacteria in mechanically ventilated patients.MethodsBacterial colonization of the stomach and the respiratory tract was qualitatively and quantitatively analyzed over time in 41 consecutive mechanically ventilated patients in a Swedish intensive care unit (ICU), with special emphasis on elucidation of the role of anaerobic bacteria in the lower respiratory tract. Samples were taken from the oropharynx, gastric juice, subglottic space and trachea within 24 h (median 14 h) of intubation, and then every third day until day 18 and every fifth day until day 33.ResultsThe patients were often heavily colonized with microorganisms not considered to belong to a healthy normal oropharyngeal and gastric flora on admission to the ICU. A majority harbored enterococci, coagulase-negative staphylococci and Candida spp. in at least one site on day 1. Anaerobic bacteria, mainly peptostreptococci and Prevotella spp., were isolated from subglottic and/or tracheal secretions in 59% of the patients. Different routes of tracheal colonization for different groups of microorganisms were found. Primary or concomitant colonization of the oropharynx with staphylococci, enterococci, enterobacteria and Candida was often seen, while Pseudomonas spp., other non-fermenting Gram-negative rods and several anaerobic species often primarily colonized the trachea, indicating exogenous or direct gastrointestinal routes of colonization.ConclusionsMechanically ventilated patients were heavily colonized in their lower airways by potential pathogenic microorganisms, including a high load of anaerobic bacteria. Different routes of colonization were shown for different species

Rates of cholesterol, ubiquinone, dolichol and dolichyl-P biosynthesis in rat brain slices

AbstractSlices from the brain and liver of rats were prepared and upon incubation exhibited a continuous and high capacity for incorporation of radioactive precursors into proteins and lipids. Using [3H]mevalonate as precursor, the rates of biosynthesis of cholesterol, ubiquinone, dolichol and dolichyl-P in brain slices were determined and found to be 5.5,0.25,0.0093 and 0.0091 nmol/h/g, respectively. Dolichol and dolichyl-P accumulate to a limited extent, but almost all of these lipids in the brain originate from de novo synthesis. The calculated half-lives for cholesterol, ubiquinone, dolichol and dolichyl-P were 4076, 90, 1006 and 171 h, respectively. The results indicate that lipids formed via the mevalonate pathway in the brain have an active and independently regulated biosynthesis

Sulphate-controlled Diversity of Subterranean Microbial Communities over Depth in Deep Groundwater with Opposing Gradients of Sulphate and Methane

The groundwater system in Olkiluoto, Finland, is stratified with a mixing layer at a depth of approximately 300m between sulphate-rich, methane-poor and sulphate-poor, methane-rich groundwaters. New sequence library data obtained by 454 pyrotag sequencing of the v4v6 16S rDNA region indicated that sulphate-reducing bacteria (SRB) dominated the mixing layer while SRB could not be detected in the deep sulphate-poor groundwater samples. With the indispensable support of the sequence data, it could be demonstrated that sulphate was the only component needed to trigger a very large community transition in deep sulphate-poor, methane-rich groundwater from a non-sulphate-reducing community comprising Hydrogenophaga, Pseudomonas, Thiobacillus, Fusibacter, and Lutibacter to a sulphate-reducing community with Desulfobacula, Desulfovibrio, Desufobulbaceae, Desulfobacterium, Desulfosporosinus, and Desulfotignum. Experiments with biofilms and planktonic microorganisms in flow cells under in situ conditions confirmed that adding sulphate to the sulphate-poor groundwater generated growth of cultivable SRB and detectable SRB-related sequences. It was also found that the 16S rDNA diversity of the biofilms was conserved over 103 d and that there was great similarity in diversity between the microorganisms in the biofilms and in the flowing groundwater. This work demonstrates that the presence/absence of only one geochemical parameter, i.e., sulphate, in the groundwater significantly influenced the diversity of the investigated subterranean microbial community

Veterinarians in the UK on the use of non-steroidal anti-inflammatory drugs (NSAIDs) for post-disbudding analgesia of calves

<p>Top 20 down-regulated genes after DAPT treatment in P0 Lfng-GFP⁺ cells.</p

Risk of adverse events in patients prescribed long‐term opioids: a cohort study in the UK Clinical Practice Research Datalink

Background Long‐term opioid prescribing for musculoskeletal pain is controversial due to uncertainty regarding effectiveness and safety. This study examined the risks of a range of adverse events in a large cohort of patients prescribed long‐term opioids using the UK Clinical Practice Research Datalink. Methods Patients with musculoskeletal conditions starting a new long‐term opioid episode (defined as ≥3 opioid prescriptions within 90 days) between 2002 and 2012 were included. Primary outcomes: major trauma and intentional overdose (any). Secondary outcomes: addiction (any), falls, accidental poisoning, attempted suicide/self‐harm, gastrointestinal pathology and bleeding, and iron deficiency anaemia. “Control” outcomes (unrelated to opioid use): incident eczema and psoriasis. Results A total of 98,140 new long‐term opioids users (median age 61, 41% male) were followed for (median) 3.4 years. Major trauma risk increased from 285 per 10,000 person‐years without long‐term opioids to 369/10,000 for a long‐term opioid episode (<20 mg MED), 382/10,000 (20–50 mg MED), and 424/10,000 (≥50 mg MED). Adjusted hazard ratios were 1.09 (95% CI; 1.04, 1.14 for <20 mg MED vs. not being in an episode of long‐term prescribing), 1.24 (95% CI; 1.16, 1.32: 20–50 mg MED) and 1.34 (95% CI; 1.20, 1.50: ≥50 mg MED). Significant dose‐dependent increases in the risk of overdose (any type), addiction, falls, accidental poisoning, gastrointestinal pathology, and iron deficiency anaemia were also found. Conclusions Patients prescribed long‐term opioids are vulnerable to dose‐dependent serious adverse events. Opioid prescribing should be reviewed before long‐term use becomes established, and periodically thereafter to ensure that patients are not being exposed to increased risk of harm, which is not balanced by therapeutic benefit. Significance Long‐term opioid use is associated with serious adverse events such as major trauma, addiction and overdose. The risk increases with higher opioid doses. Opioid prescribing should be reviewed before long‐term use becomes established, and periodically thereafter to assess ongoing effectiveness