Interactions between pectin, starch and linoleic acid and their effects on starch structure, digestion and release properties.

This study aimed at gaining insight into the mechanism of interactions between pectin (PE), starch and unsaturated fatty acids (UFAs) in relation to structure, in vitro digestibility and release properties of starch. Due to the barrier and encapsulation effects of PE, the complexing behavior of potato starch (PtS) with linoleic acid (LOA) was enhanced, which increased the complexing index, the compactness of network structure, short-range ordered structure and relative crystallinity of PtS-LOA-PE films. These structural changes resulted in the increases of slowly digestible starch and resistant starch and in the decreases of first-order rate coefficient in PtS-LOA-PE films. Besides, the in vitro release results also showed that the release properties of PtS-LOA could be controlled by the PE addition with the decreases in LOA release rate and increase in LOA bioavailability under simulated gastrointestinal conditions. Notably, at different PtS-LOA:PE ratios, the PtS-LOA-PE film with the PtS-LOA:PE ratio of 5:1 showed the better complexing degree, structural order, anti-digestibility and colon-targeted release properties than other PtS-LOA-PE films. These results indicated that PE influenced the release properties of the PtS-LOA-PE films, which was closely related to their complexing degree, structural order, and digestibility. This study provided new insights into the design of resistant films for delivery of UFAs to colon.

Effects of OSA-starch-fatty acid interactions on the structural, digestibility and release characteristics of high amylose corn starch.

This study investigated the effects of octenyl succinic anhydride (OSA)-starch-fatty acid (FA) interactions on the structural, digestibility and release characteristics of high amylose corn starch (HAS). FTIR and XRD analysis showed that the hydrophobic interaction between HAS and FA promoted the covalent binding between OSA and HAS. With the increasing of the FA chain length, the complex index, degree of substitution, R1047/1022 and relative crystallinity of OSA-HAS-FA increased first and then decreased, whereas the first-order rate coefficient and percentage of digested in infinite time showed an opposite trend. Structural changes and the molecular interactions of OSA-HAS-FA with 12­carbon FA resulted in highest resistant starch content (45.43%) and encapsulation efficiency of curcumin (Cur) (47.98%). In vitro release test revealed that Cur could be gradually released from OSA-HAS-FA in simulated gastric, intestinal and colonic fluids. Results provided novel insights into HAS-FA complex grafted with OSA as carrier for colon-specific of functional materials.

Quantitative profiling of human translation initiation reveals regulatory elements that potently affect endogenous and therapeutically modified mRNAs.

mRNA therapeutics offer a potentially universal strategy for the efficient development and delivery of therapeutic proteins. Current mRNA vaccines include chemically modified nucleotides to reduce cellular immunogenicity. Here, we develop an efficient, high-throughput method to measure human translation initiation on therapeutically modified as well as endogenous RNAs. Using systems-level biochemistry, we quantify ribosome recruitment to tens of thousands of human 5' untranslated regions and identify sequences that mediate 250-fold effects. We observe widespread effects of coding sequences on translation initiation and identify small regulatory elements of 3-6 nucleotides that are sufficient to potently affect translational output. Incorporation of N1-methylpseudouridine (m1Ψ) selectively enhances translation by specific 5' UTRs that we demonstrate surpass those of current mRNA vaccines. Our approach is broadly applicable to dissect mechanisms of human translation initiation and engineer more potent therapeutic mRNAs. Highlights: Measurement of >30,000 human 5' UTRs reveals a 250-fold range of translation outputSystematic mutagenesis demonstrates the causality of short (3-6nt) regulatory elementsN1-methylpseudouridine alters translation initiation in a sequence-specific mannerOptimal modified 5' UTRs outperform those in the current class of mRNA vaccines.

Assessment of sedation by automated pupillometry in critically ill patients: a prospective observational study.

BACKGROUND: Quantitative measurement of pupil change has not been assessed against the Richmond Agitation and Sedation Scale (RASS) and spectral edge frequency (SEF) during sedation. The aim of this study was to evaluate pupillometry against these measures in sedated critically ill adult patients. METHODS: In ventilated and sedated patients, pupillary variables were measured by automated pupillometry at each RASS level from -5 to 0 after discontinuation of hypnotics, while processed electroencephalogram variables were displayed continuously and SEF was recorded at each RASS level. Correlations were made between percentage pupillary light reflex (%PLR) and RASS, and between %PLR and SEF. The ability of %PLR to differentiate light sedation (RASS ≥-2), moderate (RASS =-3), and deep sedation (RASS ≤-4) was assessed by areas under receiver operating characteristic (ROC) curves. RESULTS: A total of 163 paired measurements were recorded in 38 patients. With decreasing sedation depth, median %PLR increased progressively from 20% (interquartile range 17-25%) to 36% (interquartile range 33-40%) (P<0.001). Strong correlations were found between %PLR and RASS (Rho=0.635) and between %PLR and SEF (R=0.641). Area under the curve (AUC) of 0.87 with a %PLR threshold of 28% differentiated moderate/light sedation from deep sedation with sensitivity of 83% and specificity of 83%. An AUC of 0.82 with a threshold of 31% distinguished light sedation from moderate/deep sedation with a sensitivity of 81% and a specificity of 75%. CONCLUSIONS: Quantitative assessment of %PLR correlates with other indicators of sedation depth in critically ill patients.