European survey on Paediatric Early Warning Systems, and other processes used to aid the recognition and response to children's deterioration on hospital wards.

BACKGROUND: Internationally, there is an increasing trend in using Rapid Response Systems (RRS) to stabilize in-patient deterioration. Despite a growing evidence base, there remains limited understanding of the processes in place to aid the early recognition and response to deteriorating children in hospitals across Europe. AIM/S: To describe the processes in place for early recognition and response to in-patient deterioration in children in European hospitals. STUDY DESIGN: A cross-sectional opportunistic multi-centre European study, of hospitals with paediatric in-patients, using a descriptive self-reported, web-based survey, was conducted between September 2021 and March 2022. The sampling method used chain referral through members of European and national societies, led by country leads. The survey instrument was an adaptation to the survey of Recognition and Response Systems in Australia. The study received ethics approval. Descriptive analysis and Chi-squared tests were performed to compare results in European regions. RESULTS: A total of 185 questionnaires from 21 European countries were received. The majority of respondents (n = 153, 83%) reported having written policies, protocols, or guidelines, regarding the measurement of physiological observations. Over half (n = 120, 65%) reported that their hospital uses a Paediatric Early Warning System (PEWS) and 75 (41%) reported having a Rapid Response Team (RRT). Approximately one-third (38%) reported that their hospital collects specific data about the effectiveness of their RRS, while 100 (54%) reported providing regular training and education to support it. European regional differences existed in PEWS utilization (North = 98%, Centre = 25%, South = 44%, p < .001) and process evaluation (North = 49%, Centre = 6%, South = 36%, p < .001). CONCLUSIONS: RRS practices in European hospitals are heterogeneous. Differences in the uptake of PEWS and RRS process evaluation emerged across Europe. RELEVANCE TO CLINICAL PRACTICE: It is important to scope practices for the safe monitoring and management of deteriorating children in hospital across Europe. To reduce variance in practice, a consensus statement endorsed by paediatric and intensive care societies could provide guidance and resources to support PEWS implementation and for the operational governance required for continuous quality improvement.

Changes in vineyard soil parameters after repeated application of organic-inorganic amendments based on spent mushroom substrate.

The changes of physicochemical and biochemical parameters of a silty loam (S1) and sandy loam (S2) vineyard soils added with spent mushroom substrate (SMS) or SMS composted with ophite (OF) as rock dust (SMS + OF) were studied. Two doses of SMS or SMS + OF (25 and 100 Mg ha-1) were applied for two consecutive years (2020-2021) and changes of soil physicochemical parameters, and dehydrogenase activity (DHA), respiration (RES), microbial biomass (BIO), and the phospholipid fatty acids (PLFAs) profile were assayed on a temporal basis. The results showed an increase in soil organic carbon (OC) content, total and mineralised N, P, and K, especially when the highest SMS dose was applied to soils. Repeated application caused OC content over time up to 2.3 times higher than initial content in the silty loam soil. This increase was not observed in sandy soil, possibly due to a higher bioavailability of OC, as indicated by the evolution of extractable humic acid/fulvic acid pools. In both soils, all biochemical parameters increased after amendment, being favoured both by the OC and by the presence of OF. Significant positive correlations were found between DHA, RES and BIO, and OC content especially in the first part and then levelled off after the second dose application. Total bacterial or fungal PLFAs patterns reflected the variation of BIO by SMS application. The higher growth of fungi vs. bacterial community in amended soils was recorded after the first SMS application, although the opposite effect occurred after the second application, with similar results in both soils. The findings indicate that the application of SMS or SMS + OF in vineyard soils could be an appropriate agronomic management practice for maintaining soil sustainability, although doses and application times of these amendments should first be evaluated depending on soil texture.

Feasibility and Utility of the Venous Excess Ultrasound Score to Detect and Grade Central Venous Pressure Elevation in Critically Ill Children.

OBJECTIVES: The Venous Excess Ultrasound (VExUS) score has been described as a useful tool to estimate the degree of venous congestion in adult patients. The present study aimed to analyze the feasibility and usefulness of the VExUS score to detect and grade central venous pressure (CVP) elevation in critically ill children. METHODS: A cross-sectional pilot study was conducted in a tertiary-care pediatric intensive care unit between November 2020 and June 2021. All children in whom CVP was monitored, were enrolled. At the time of central venous catheter placement, CVP and VExUS score grade were determined, analyzing the inferior vena cava (IVC) diameter and the hepatic (HVD), portal (PVD), and intrarenal (IRVD) venous Doppler waveforms. RESULTS: A total of 33 children were studied (median age 12.2 [interquartile range (IQR) 4.1-100.6] months old; median weight 8.5 [IQR 5.6-35] kg; 20 [60.6%] males). The VExUS score was successfully obtained in 100% of the patients and its severity was strongly associated with the CVP levels (P < .001). Analyzing the VExUS score components separately, IVC dilation (P < .001) and severe HVD (P = .026), mild IRVD (P = .005), and severe IRVD (P = .025) patterns were associated with elevated CVP. After adjustment for confounding factors, IRVD pattern remained the only independent variable associated with elevated CVP. CONCLUSIONS: The VExUS score appears to be a feasible and potentially useful bedside noninvasive monitoring tool for the detection and grading of CVP elevation in critically ill children. Among all its components, IRVD assessment seems most associated with high CVP in this population.

Efficient controlled release of cannabinoids loaded in γ-CD-MOFs and DPPC liposomes as novel delivery systems in oral health.

Olivetol (OLV), as a cannabidiol (CBD) analog, was incorporated in γ-cyclodextrin metal-organic frameworks (γ-CD-MOFs) and 1,2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC) liposomes as potential analgesic drug delivery systems (DDS) for dental hypersensitivity (DH) treatment. These DDS have been scarcely employed in oral health, being the first time in case of MOFs loaded with cannabinoids. In vitro experiments using bovine teeth were performed to verify if the drug is able to reach the dentin, where it can flow to the pulp tissues and exert its analgesic effect; enamel and dentin regions were analyzed by synchrotron radiation-based FTIR microspectroscopy. Principal component analysis (PCA) was used to process the spectroscopic data as a powerful chemometric tool, and it revealed a similar behavior in both regions. The studied DDS have been characterized by different techniques, and is was demonstrated that DDS is an efficient way to carry the drug through dental tissues without compromising their structure.

Combination of Two Synchrotron Radiation-Based Techniques and Chemometrics to Study an Enhanced Natural Remineralization of Enamel.

The limitations to assess dental enamel remineralization have been overcome by a methodology resulting from the appropriate combination of synchrotron radiation-based techniques on both, infrared microspectroscopy and micro X-ray diffraction, with the help of specific data mining. Since amelogenin plays a key role in modulating the mineralization of tooth enamel, we propose a controlled ion release for fluorapatite structural ions (Ca2+, PO43-, and F-, also including Zn2+) by using weak acid and weak base ion-exchange resins in the presence of amelogenin to remineralize the surface of etched teeth. This combination provides the necessary ions for enamel remineralization and a guide for crystal growth due to the protein. Remineralized tooth samples were analyzed by applying the indicated methodology. The synchrotron data were treated using principal component analysis and multivariate curve resolution to analyze the mineral layer formed in the presence and absence of amelogenin. The remineralizing treatment created a fluorapatite layer free of carbonate impurities and with a similar orientation to that of the natural enamel thanks to amelogenin contribution.

The power of weak ion-exchange resins assisted by amelogenin for natural remineralization of dental enamel: an in vitro study.

This study aims to develop an innovative dental product to remineralize dental enamel by a proper combination of ion-exchange resins as controlled release of mineral ions that form dental enamel, in the presence of amelogenin to guide the appropriate crystal growth. The novel product proposed consists of a combination of ion-exchange resins (weak acid and weak base) individually loaded with the remineralizing ions: Ca2+, PO43- and F-, also including Zn2+ in a minor amount as antibacterial, together with the protein amelogenin. Such cocktail provides onsite controlled release of the ions necessary for enamel remineralization due to the weak character of the resins and at the same time, a guiding tool for related crystal growth by the indicated protein. Amelogenin protein is involved in the structural development of natural enamel and takes a key role in controlling the crystal growth morphology and alignment at the enamel surface. Bovine teeth were treated by applying the resins and protein together with artificial saliva. Treated teeth were evaluated with nanoindentation, scanning electron microscopy and energy-dispersive X-ray spectroscopy. The innovative material induces the dental remineralization creating a fluorapatite layer with a hardness equivalent to sound enamel, with the appropriate alignment of corresponding nanocrystals, being the fluorapatite more acid resistant than the original mineral. Our results suggest that the new product shows potential for promoting long-term remineralization leading to the inhibition of caries and protection of dental structures.

Staphylococcal toxic shock syndrome in a child with interleukin-17 inhibitor treatment for psoriasis.

A 6-year-old girl presented with fever, skin rash, anuria, and conjunctivitis that rapidly progressed to toxic shock syndrome. Following hospital discharge, she developed a staphylococcal abscess on the lower extremity. She had recently received the first two doses of the interleukin-17 (IL-17) inhibitor secukinumab for resistant plaque psoriasis. IL-17 is known to be essential in host defense against Staphylococcus aureus. To our knowledge, this is the first reported case of staphylococcal toxic shock syndrome (STSS) associated with an IL-17 inhibitor.

Breaking the rules: tooth whitening by means of a reducing agent.

OBJECTIVES: It is widely accepted that current tooth whitening treatment effect is based on the oxidizing action of peroxides, even if the mechanism of action remains still unclear. Treatments are claimed to be safe, but several secondary effects have been described, since long application times and high concentrations are needed. A faster whitening ingredient which permits the use of lower concentrations and shorter application times could potentially overcome this problem. In this work, a different approach based on a reducing agent, sodium metabisulfite (MBS), is explored. MATERIALS AND METHODS: The reaction between tannic acid (TA) with carbamide peroxide (CP), MBS, and potassium persulfate (PS), as an oxidizing agent, was monitored for 48 hours by measuring its absorbance, comparing their different whitening effects. The reduction process between TA and MBS was confirmed by cyclic voltammetry. An in vitro test was used to observe if MBS whitens also stained teeth. RESULTS: It is shown that MBS bleaching effect is faster and higher than CP's effect over time. PS produced a darkening effect after the 3rd hour because of the strong absorbance of the oxidation metabolite. Cyclic voltammetry showed a progressive increase in the intensity of the TA anodic peak when MBS was present, demonstrating that a reduction is taking place. In vitro, MBS showed a faster whitening performance than CP, using lower concentrations. CONCLUSIONS: Using a TA solution as a staining model, it was possible to show that MBS has a visible bleaching effect through a reduction reaction, faster than CP, both in solution and in vitro. Low concentrations of MBS are effective in whitening. CLINICAL SIGNIFICANCE: This work shows MBS as a promising candidate to develop novel whitening treatments, which is acting by reducing mechanism instead of oxidation.

Optogenetic Modulation of Neural Progenitor Cells Improves Neuroregenerative Potential.

Neural progenitor cell (NPC) transplantation possesses enormous potential for the treatment of disorders and injuries of the central nervous system, including the replacement of lost cells or the repair of host neural circuity after spinal cord injury (SCI). Importantly, cell-based therapies in this context still require improvements such as increased cell survival and host circuit integration, and we propose the implementation of optogenetics as a solution. Blue-light stimulation of NPCs engineered to ectopically express the excitatory light-sensitive protein channelrhodopsin-2 (ChR2-NPCs) prompted an influx of cations and a subsequent increase in proliferation and differentiation into oligodendrocytes and neurons and the polarization of astrocytes from a pro-inflammatory phenotype to a pro-regenerative/anti-inflammatory phenotype. Moreover, neurons derived from blue-light-stimulated ChR2-NPCs exhibited both increased branching and axon length and improved axon growth in the presence of axonal inhibitory drugs such as lysophosphatidic acid or chondroitin sulfate proteoglycan. Our results highlight the enormous potential of optogenetically stimulated NPCs as a means to increase neuroregeneration and improve cell therapy outcomes for enhancing better engraftments and cell identity upon transplantation in conditions such as SCI.

Mobility monitoring of two herbicides in amended soils: A field study for modeling applications.

This paper reports the mobility and total balance of chlorotoluron (CTL), flufenacet (FNC) and bromide ion (Br-) throughout a sandy soil profile after the application of spent mushroom substrate (SMS) and green compost (GC). Obtaining mobility dataset is crucial to simulate the herbicides' fate under amended soil scenarios by application pesticide leaching models with regulatory application (FOCUS models). The application of organic residues is nowadays increased to improve the crop yields and there is a gap in the simulations of this kind of amended scenarios. A two-year field experiment involving unamended soil (S) and SMS- or GC-amended soil plots was conducted. CTL, FNC, and Br- were annually applied and their residual concentrations were determined in soil profiles (0-100 cm) regularly sampled. In all the treatments the order of mobility is followed as FNC < CTL < Br-. SMS and GC increased herbicide retention in the top 10 cm by the higher organic carbon (OC) content than the unamended soil, and their ability to increase the soil's water-holding capacity and to decrease water percolation. Simultaneously dissolved organic carbon (DOC) content facilitated herbicide transport being it favoured by the initial soil moisture content and the rainfall shortly after the chemicals' initial application. Over the first year, residual amounts (<2.6%) of Br-, CTL and FNC were leached down to 90-100 cm depth in the three treatments. However, over the second year low CTL and FNC amounts (<1.0%) reached the bottom layer only in S + SMS although high Br- concentrations did so in the three treatments (<20%). According to the total balance of Br-, CTL, and FNC in the soil profiles other processes (degradation, mineralisation, bound residues formation, and/or crop uptake) different from leaching below 1 m depth might play a key role in their dissipation especially in the amended soil profiles. SMS and GC are likely to be used as organic amendments to preserve the soil and water quality but in the case of SMS, its higher DOC content could imply a higher potential risk for groundwater contamination than GC.

Assessment of 14C-prosulfocarb dissipation mechanism in soil after amendment and its impact on the microbial community.

Adding organic amendments to soil could modify the bioavailability of herbicides and lead to changes in the microbial community's activity and structure. The objective here was to study the dissipation and total mass balance of 14C-labeled prosulfocarb applied at two rates (4 and 10 mg kg-1) in unamended and green compost (GC)-amended soil. Soil dehydrogenase activity (DHA) and phospholipid fatty acid (PLFA) profile analysis were determined to evaluate the effect of herbicide residues on microbial community's activity and structure over the dissipation period. The dissipation rate of prosulfocarb decreased after soil amendment due to higher herbicide adsorption by the amended soil. The 50% dissipation time (DT50) increased 1.7 times in the unamended soil when the concentration of prosulfocarb increased 2.5 times. The mass balance results indicate that the sum of water and organic extractable fractions represented the highest amounts up to the dissipation of 50% 14C-prosulfocarb. The 14C-herbicide was then mainly mineralized (up to 11%-31%) or formed non-extractable residues (up to 35%-44%). The amount of 14C-prosulfocarb residues extracted with methanol was slightly higher in amended soils than in unamended ones. 14C-prosulfocarb mineralization was higher in unamended soils than in amended ones. The formation of non-extractable residues was continuous, and increased over time. Soil DHA decreased in the unamended soil and was maintained in the GC-amended soil at the end of the assay. The microbial structure was barely disturbed over the prosulfocarb degradation process, although it was clearly influenced by the application of GC. The results obtained reveal the influence organic amendment has on herbicide bioavailability to decrease its biodegradation and buffer its impact on the soil microbial structure.

Tooth whitening: From the established treatments to novel approaches to prevent side effects.

OBJECTIVE: The aim is to review the most important aspects about tooth whitening treatments, their side effects, and the new emerging approaches to overcome them. OVERVIEW: This review is focused on origin of tooth stains, the whitening systems and their chemistry, their side effects, and the new approaches. The search of bibliography of the period 1965-2018 has been analyzed. CONCLUSIONS: Tooth whitening has become one of the most requested dental treatments by the public. Tooth stains are classified according to their origin into two categories: intrinsic and extrinsic. The whitening systems are generally organized into two classes: in-office and at-home products. Most of the whitening systems use hydrogen peroxide as the active oxidative agent to degrade the organic compounds that cause stains. The concentration ranges depending on the treatment, and it may be applied directly or produced in a chemical reaction from carbamide peroxide that is more stable. Besides its popularity, tooth whitening still has some side effects being tooth hypersensitivity the most common. In order to decrease these side effects, new treatments are constantly in renewal processes. CLINICAL SIGNIFICANCE: Despite all the data and new strategies known about tooth whitening, there are many aspects that are not totally fully understood and methodologies that are not completely effective. Therefore, the development of effective, efficient, and long-lasting whitening treatments is still necessary.

Dissipation of herbicides after repeated application in soils amended with green compost and sewage sludge.

Certain agricultural practices, such as the repeated application of herbicides or organic amendments to soil, can influence herbicide dissipation. This research has studied the effects of two repeated applications of mesotrione, pethoxamid, and triasulfuron on their dissipation rates in unamended soil (S) and soil amended with green compost (S+GC) or sewage sludge (S+SS). The dissipation experiment has also included an evaluation of the adsorption of the three herbicides by soils and of changes in soil dehydrogenase activity (DHA). The adsorption of the three herbicides by amended soils (Kf range 0.83-2.98) was higher than by unamended soil (Kf range 0.20-0.64). The adsorption coefficients (Kd) of mesotrione and triasulfuron were higher for S+SS, while that of pethoxamid was higher for S+GC, but no relationship between values for the time to 50% degradation (DT50) and adsorption coefficients could be determined. The repeated application of mesotrione decreased its dissipation rate in unamended soil (DT50 increased from 4.75 to 8.15 days) and amended soils (DT50 increased from 11.7 to 28.2 days in S+GC and from 17.7 to 37.9 in S+SS), whereas the repeated application of pethoxamid increased its dissipation rate in all the treatments, and the rate for triasulfuron increased only in amended soils. The highest DT50 values for pethoxamid (12.3 days) and triasulfuron (57.1 days) were in S+GC, and the lowest in S+SS (8.35 and 24.7 days). Soil DHA was stimulated by the presence of GC in the soil and by the first application of mesotrione. The second application of mesotrione and pethoxamid positively affected soil DHA, but this did not occur for triasulfuron. The repeated applications of herbicides and soil organic amendments have different effects on herbicide dissipation, adsorption, and soil DHA, and they should be taken into account when assessing soil quality and other potential environmental implications of pesticide use.

Development of a procedure for the multiresidue analysis of pesticides in vineyard soils and its application to real samples.

A procedure for multiresidue analysis was developed for the extraction and determination of 17 pesticides, including herbicides, fungicides, and insecticides, as well as certain degradation products, in vineyard soils from La Rioja region (Spain). Different solvents and mixtures were tested in spiked pesticide-free soils, and pesticides were comparatively evaluated by gas chromatography with mass spectrometry and liquid chromatography with mass spectrometry. Recoveries >70%, with relative standard deviations <9%, were obtained when a mixture of methanol/acetone or a mixture of methanol/CaCl2 0.01 M for the most polar compounds was selected as the extraction solvent. Method validation was accomplished with acceptable linearity (r(2) ≥ 0.987) within the concentration range of 0.005-1 µg/mL corresponding to 1.667-333.4 µg/kg and 0.835-167.1 µg/kg for liquid chromatography with mass spectrometry and gas chromatography with mass spectrometry, respectively, and detection limits <0.4 µg/kg for the compounds were studied. The extraction method was applied to 17 real vineyard soil samples, and terbuthylazine and its metabolite desethylterbuthylazine were the most ubiquitous compounds, as they were detected in the 100% of the soils analyzed. The presence of fungicides was also high, and the presence of insecticides was lower than other pesticides. The results confirm the usefulness of the optimized procedure for monitoring residues in vineyard soils.

Sustainable agricultural practices influence s-metolachlor, foramsulfuron and thiencarbazone-methyl degradation and their metabolites formation.

The effect of sustainable agricultural practices, such as mulching or the application of straw residues as an organic amendment, on the degradation, dissipation and persistence in the soil of S-metolachlor (SMOC), foramsulfuron (FORAM) and thiencarbazone-methyl (TCM) is still unclear. The objective here was to conduct a laboratory experiment to evaluate the impact of milled wheat straw (WS) simulating its individual use as mulch or applied as an organic amendment to two agricultural soils: unamended and WS-amended soils on the degradation kinetics of the herbicides SMOC, FORAM and TCM, and on the formation of their major metabolites at two incubation temperatures (14 °C and 24 °C). The degradation rate of SMOC on WS was 6.9-16.7 times faster than that observed for FORAM and TCM at both temperatures. The half-life (DT50) values were 1.1-10.6 times lower for FORAM than for SMOC and TCM in the unamended and WS-amended soils at 14 °C and 24 °C. The application of WS to soils increased the DT50 values from 1.1 to 11.2 times for all the herbicides at both incubation temperatures due to their higher adsorption and lower bioavailability. The herbicides recorded a faster degradation at 24 °C (1.2-3.9 times) than at 14 °C, according to Q10 values >1. SMOC metabolites were more persistent in WS-amended soils than in unamended ones, in agreement with the DT50 values recorded for the parent compound. The results indicate that the effect of the mulch applied to soils as an organic amendment was different depending on the herbicide and incubation temperature. The outcomes of this research can give key suggestions for reducing the effects of residual herbicides following sustainable agricultural practices by avoiding soil and groundwater contamination, which is one of the challenges involved in the application of chemical inputs.

Is auditor financial decision-making affected by prior audit report information? A behavioral approach.

The role of financial experts is to provide their professional judgments with an opinion included in the financial reports after reviewing an entity's financial information, following a specific audit process. We investigate whether confirmation bias (through prior audit opinions) occurs among auditors during the audit process and decision-making, and whether experience mitigates this effect. A total of 175 non-experienced auditors run a 2x4 between-subjects experiment (experiment 1) studying how financial information (IV with two levels: negative and neutral/positive) and previous audit report (IV with four levels: absence, negative, moderately negative, and positive) might influence the issuance of the subsequent decision-making (DV). In addition, a total of 32 junior level 1 auditors (less than one year of experience), 31 junior level 2 auditors (up to 3 years of experience) and 20 senior auditors (more than 3 years of experience) run a 2 × 4 × 3 between-subjects experiment (experiment 2) analyzing if experience (IV with three levels of experience: less than one-year, between one and three years, more than three years) mitigates this effect (experiment 2). Results confirm that the previous-year audit report affect auditors' current assessment, showing that positive and negative prior opinions persuade auditors when suggesting the next one. This finding is relevant as auditors' opinions could be conditioned by prior opinions instead of their own expertise. Our evidence also suggests that professional experience mitigates this influence on auditors' assessments. Consequently, this study has relevant implications for partners, audit professionals and audit firm recruiters. A general implication is that auditor training courses should reinforce the auditor's own expertise and criteria based on the deep analysis of financial and economic data rather than on the work of previous auditors.

Phytochemical Profile, Bioactive Properties, and Se Speciation of Se-Biofortified Red Radish (Raphanus sativus), Green Pea (Pisum sativum), and Alfalfa (Medicago sativa) Microgreens.

The impact of selenium (Se) enrichment on bioactive compounds and sugars and Se speciation was assessed on different microgreens (green pea, red radish, and alfalfa). Sodium selenite and sodium selenate at a total concentration of 20 µM (1:1) lead to a noticeable Se biofortification (40-90 mg Se kg-1 DW). In green pea and alfalfa, Se did not negatively impact phenolics and antioxidant capacity, while in red radish, a significant decrease was found. Regarding photosynthetic parameters, Se notably increased the level of chlorophylls and carotenoids in green pea, decreased chlorophyll levels in alfalfa, and had no effect on red radish. Se treatment significantly increased sugar levels in green pea and alfalfa but not in red radish. Red radish had the highest Se amino acid content (59%), followed by alfalfa (34%) and green pea (28%). These findings suggest that Se-biofortified microgreens have the potential as functional foods to improve Se intake in humans.

Selenium biofortification of microgreens: Influence on phytochemicals, pigments and nutrients.

Kale (Brassica oleracea L. var. sabellica L.), kohlrabi (Brassica oleracea L. var. gongylodes L.) and wheat (Triticum aestivum L. cv. Bancal) microgreens were cultivated in presence of selenium 20 µmol L-1 as sodium selenite and sodium selenate mixture. The influence of this biofortification process was evaluated in terms of biomass production, total Se, macro- and micronutrients concentration, polyphenols, antioxidant activity, chlorophylls and carotenoids levels and total soluble proteins content. The results obtained have shown a significant concentration of total Se in the biofortified microgreens of kale (133 µg Se·g-1 DW) and kohlrabi (127 µg Se·g-1 DW) higher than that obtained for wheat (28 µg Se·g-1 DW). The Se uptake in all the species did not produce oxidative damage to the plants reflected in the bioactive compounds, antioxidant capacity or pigments concentration. These Se-enriched microgreens may contribute to the recommended intake of this nutrient in human diet as to overcome Se-deficiency.

Liposomes as selenium nanocarriers for foliar application to wheat plants: A biofortification strategy.

In the present work, liposomes have been used as nanocarriers in the biofortification of wheat plants with selenium (Se) through foliar application. Liposomal formulations were prepared using 1,2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC) and Phospholipon®90H (P90H) (average size <100 nm), loaded with different concentrations of inorganic Se (selenite and selenate) and applied twice to the plants in the stage of vegetative growth. Liposomes enhanced Se uptake by wheat plants compared to direct application. The highest Se enrichment was achieved using the phospholipid DPPC and a concentration of 1000 µmol·L-1 of Se without affecting the biomass, chlorophylls, carotenoids, and the concentration of mineral nutrients of the plants. The chemical speciation of Se in the plants was further investigated by X-ray absorption spectroscopy (XAS). The results from XAS spectra revealed that most of the inorganic Se was transformed to organic Se and that the use of liposomes influenced the proportion of C-Se-C over C-Se-Se-C species.

Improved conformational stability of the visual G protein-coupled receptor rhodopsin by specific interaction with docosahexaenoic acid phospholipid.

Rhodopsin is the photoreceptor located in the rod cells of the retina. It has seven transmembrane helices and is a prototypic member of the G protein-coupled receptor superfamily. The structures and functions of these receptors are clearly affected by the lipid composition of the cell membrane, and their study in a purified recombinant form is usually performed in detergent solution. There is a need to study these receptors in a physiologically relevant environment because the lipid environment is known to have an important effect on their function. In this work, rhodopsin reconstituted in docosahexaenoic acid (DHA) liposomes is shown to have more thermal stability than when it is solubilised with the neutral detergent dodecyl maltoside. Moreover, the specific interaction between rhodopsin and DHA was followed by means of Langmuir experiments with insertion of rhodopsin into lipid monolayers; this showed high affinity for the lipid-receptor interaction. Furthermore, fluorescence spectroscopy measurements indicate that the conformation of opsin obtained after photobleaching is preserved in DHA-containing liposomes, thereby allowing retinal to re-enter the binding pocket even long after bleaching. Overall, our results demonstrate that liposomes of this specific lipid provide a more stable environment for ground-state inactive rhodopsin in the dark, than dodecyl maltoside detergent, and that this lipid can also preserve the native correctly folded ligand-free opsin conformation obtained after illumination. This strategy will be used in further studies on mutations of rhodopsin associated with congenital retinopathies.