Exploring and strengthening the potential of R-phycocyanin from Nori flakes as a food colourant.

This study aimed to purify, characterise and stabilise the natural food colourant, R-phycocyanin (R-PC), from the red algae Porphyra spp. (Nori). We purified R-PC from dried Nori flakes with a high purity ratio (A618/A280 ≥ 3.4) in native form (α-helix content 53%). SAXS measurements revealed that R-PC is trimeric ((αß)3) in solution. The thermal denaturation of α-helix revealed one transition (Tm at 52 °C), while the pH stability study showed R-PC is stable in the pH range 4-8. The thermal treatment of R-PC at 60 °C has detrimental and irreversible effects on R-PC colour and antioxidant capacity (22 % of residual capacity). However, immobilisation of R-PC within calcium alginate beads completely preserves R-PC colour and mainly retains its antioxidant ability (78 % of residual capacity). Results give new insights into the stability of R-PC and preservation of its purple colour and bioactivity by encapsulation in calcium alginate beads.

Surrogate data modeling the relationship between high frequency amplitudes and Higuchi fractal dimension of EEG signals in anesthetized rats.

We used spectral analysis and Higuchi fractal dimension (FD) to correlate the EEG spectral characteristics of the sensorimotor cortex, hippocampus, and pons with their corresponding EEG signal complexities in anesthetized rats. We have explored the quantitative relationship between the mean FDs and EEG wide range high frequency (8-50 Hz) activity during ketamine/xylazine versus nembutal anesthesia at surgical plane. Using FD we detected distinct inter-structure complexity pattern and uncovered for the first time that the polygraphically and behaviorally defined anesthetized state at surgical plane as equal during experiment in two anesthetic regimens, is not the same with respect to the degree of neuronal activity (degree of generalized neuronal inhibition achieved) at different brain levels. Using the correlation of certain brain structure EEG spectral characteristics with their corresponding FDs, and the surrogate data modeling, we determined what particular frequency band contributes to EEG complexities in ketamine/xylazine versus nembutal anesthesia. In this study we have shown that the quantitative relationship between higher frequency EEG amplitude and EEG complexity is the best-modeled by surrogate data as a 3rd order polynomial. On the base of our EEG amplitude/EEG complexity relationship model, and the evidenced spectral differences in ketamine versus nembutal anesthesia we have proved that higher amplitudes of sigma, beta, and gamma frequency in ketamine anesthesia yields to higher FDs.

A quality of life assessment and the correlation between generic and disease-specific questionnaires scores in outpatients with chronic liver disease-pilot study.

INTRODUCTION: Chronic liver diseases (CLD) are an important cause of morbidity and mortality in general population. The aim of this study was to analyze potential differences between patients with CLD and healthy control group, and to estimate the severity of CLD by using simple questionnaires: general health questionnaire (GHQ-12) and chronic liver disease questionnaire (CLDQ). METHODS: A cross-sectional pilot study was performed in Zemun Clinical Hospital during years 2014 and 2015. Sixty participants were divided into 4 groups (15 per group): chronic alcoholic hepatitis, other chronic hepatitis, liver cirrhosis, and healthy control group. Entire study population chose one of four offered answers of structured questionnaires GHQ-12 and CLDQ, based on which mean model of end-stage liver disease (MELD) and Child-Turcotte-Pugh (CTP) scores were calculated. RESULTS: Mean GHQ12 and CLDQ scores were 10.5 and 5.21 ± 1.11 respectively. Regarding certain CLDQ domain scores, a significant difference between alcoholic and non-alcoholic hepatitis groups in the worry domain was observed. Mean MELD score was 7.42 ± 2.89 and did not differ between chronic hepatitis groups, while mean CTP score was 5.73 ± 0.88. A statistically significant correlation was observed between GHQ12 and CLDQ scores (ρ = -0.404, p < 0.01), but not between subjective and objective scores. CONCLUSIONS: Mean GHQ12 and CLDQ scores pointed out to general psychological no-distress condition of the studied participants, as well as scarcely expressed CLD-specific complaints. Mean MELD and CTP scores indicated stable chronic liver diseases, with low three-month mortality rates in the cases of chronic hepatitis, as well as determination to Child A group in the case of liver cirrhosis.