Publications

Abstract Lectin‐glycan interactions sustain fundamental biological processes involved in development and disease. Owing to their unique sugar‐binding properties, lectins have great potential in glycobiology and biomedicine. However, their relatively low affinities and broad specificities pose a significant challenge when used as analytical reagents. New approaches for expression and engineering of lectins are in demand to overcome current limitations. Herein, we report the application of bacterial display for the expression of human galectin‐3 and mannose‐binding lectin in Escherichia coli . The analysis of the cell surface expression and binding activity of the surface‐displayed lectins, including point and deletion mutants, in combination with molecular dynamics simulation, demonstrate the robustness and suitability of this approach. Furthermore, the display of functional mannose‐binding lectin in the bacterial surface proved the feasibility of this method for disulfide bond‐containing lectins. This work establishes for the first time bacterial display as an efficient means for the expression and engineering of human lectins, thereby increasing the available toolbox for glycobiology research.

The effect of fungicides on fermentation is of paramount importance to control the quality and safety of wines. In this work, the quality (enological parameters, color, phenolic content, antioxidant activity, and fungicide residues) of wines from Monastrell grapes fortified with iprovalicarb, mepanipyrim, and tetraconazole fungicides was evaluated. Along the winemaking process, initial residues of mepanipyrim and tetraconazole were removed in more than 90% while the dissipation of iprovalicarb was around 73%. Significant statistical differences were found in the presence of iprovalicarb and mepanipyrim residues, especially at the highest concentration assayed. For both fungicides, increases in the volatile acidity (between 4 and 8.6 times), the lactic acid content (between 8.6 and 20.5 times), the percentage of polymeric anthocyanins (between 1.3 and 1.7 times), and also a slight increase of the total phenolic index and the total anthocyanin content determined by spectrophotometry were observed. On the contrary, the total monomeric anthocyanins content decreased about 16.3% and 28.6% in the presence of iprovalicarb and mepanipyrim, respectively. These results could be related to a higher development of acetic acid or lactic bacteria in the presence of these fungicides. The color of the final wines was also different in comparison with the control, with a higher yellow component, color intensity, tonality, and hue angle because of pH changes in the medium. Tetraconazole fermentations had a more similar trend to the control wine, probably due to the lower concentration of this fungicide in the grape must at the initial time. No effects on the antioxidant activity was observed for any of the target fungicides. A multivariate statistical analysis was done to view the interrelationships between different variables (color and anthocyanins profile). The obtained model allowed the wines to be separated according to the fungicide treatment applied.

Abstract Major objectives of this work were to: (1) substantiate the 24‐hour pattern in the occurrence of childhood febrile seizures (CFSs) by a novel time series meta‐analysis of past reported time‐of‐day data and (2) discuss its potential circadian rhythm‐dependencies. Comprehensive search of the published literature retrieved eight articles that met inclusion criteria. Three investigations were conducted in Iran, two in Japan, and one each in Finland, Italy, and South Korea, representing a total of 2461 mostly simple febrile seizures of children who were on average about 2 years of age. Population‐mean cosinor analysis validated ( p < .001) a 24‐hour pattern in the onset of CFSs, with an approximate four‐fold difference in the proportion of children expressing seizures at its peak at 18:04 h (95% confidence interval: 16:40–19:07 h) vs trough at 06:00 h, in the absence of meaningful time‐of‐day differences in mean body temeprarure. The CFS time‐of‐day pattern likely derives from the actions of multiple circadian rhythms, particularly the cytokines that comprise the pyrogenic inflammatory pathway and melatonin that influences the excitation level of central neurons and helps regulate body temperature. Past laboratory animal and patient investigations document that the vulnerability to a seizure by a provoking trigger of the same intensity is not the same but different in a predictable‐in‐time manner during the 24 h as a circadian susceptibility/resistance rhythm. Knowledge of the marked disparity in the time‐of‐day risk of CFSs can be translated into improved prevention, particularly during the late afternoon and early evening when highest, through proper timing of prophylactic interventions.

The aging of wines is a process used to preserve wine but also to enhance its properties. It is a process of great interest, mainly because of the additional properties it adds to wines and because of its economic implications. Historically, barrels have been employed for centuries for preserving and aging wine due to their resistance and relative impermeability. In general terms, the wine aging process can be divided into two phases: oxidative and reductive aging. Oxidative aging traditionally takes place in barrels while reductive phase occurs in the bottle. During both processes, oxygen plays a fundamental role as well as other factors, for instance: temperature, light, bottle position, microbial growth or storage time. Likewise, during the aging process, a series of chemical reactions take place influencing the composition and organoleptic profile of wine. At this point, oxidative aging in barrels is a fundamental step. Barrels are directly involved in the produced changes on wine’s composition due to the transference of oxygen and phenolic and aromatic compounds from wood to wine. This way, barrels act as an active vessel capable of releasing compounds that affect and improve wine’s characteristics. Regarding, the importance of barrels during aging process, some attention must be given to the species most used in cooperage. These species are conventionally oak species, either French or American. However, other non-conventional species are currently being studied as possible wood sources for the production of wines, such as chestnut robinia or other oak species. In the last decades, new approaches have been developed for barrel aging to find new alternatives more suitable, affordable and feasible to sanitize the process, such as other materials different from wood or the use of wood chips, which is regulated since 2006 by the EU. However, even though some of them have shown promising data, barrels are currently the most used technology for the oxidative stage of table wines aging.

The genus Pyrus, which includes pear species, comprises approximately 22 species and 5,000 subspecies. Pears are commercially important due to their environmental adaptability and are widely distributed across North Africa, Europe, and Asia. Pyrus species are rich in phytochemicals known for their anticancer, antiviral, and antioxidant properties. This study investigates the chemical composition and biological activity of leaf, stem, and fruit extracts of Pyrus calleryana growing in Egypt, using UPLC-MS/MS and GNPS molecular networking, and assessing antioxidant and enzyme inhibitory activities. A total of 73 compounds were identified, the majority of which were phenolic compounds. These included benzoic and cinnamic acid derivatives, flavonoids, triterpenoids, fatty acids, phospholipids, glycolipids and sugars. The stem extract exhibited significant in vitro antioxidant and enzyme inhibitory activity. Antioxidant activity of stems extract was assessed (in comparison to other organs) in several antioxidant assays, e.g. DPPH (367.06 ± 4.65 mg TE/g), ABTS (392.8 ± 7.04 mg TE/g), FRAP (206.73 ± 5.12 mg TE/g), phosphomolybdenum (1.89 ± 0.05 mmol TE/g), and others. Furthermore, the P. calleryana leaf extract inhibited MDA-MB-231 cell viability in a concentration-dependent manner after 48 h. These results highlight the promising potential of Pyrus calleryana as a rich source of bioactive compounds with antioxidant, enzyme inhibitory, and cytotoxic activities, supporting its further exploration in pharmaceutical and nutraceutical applications.

A general method to encapsulate gold nanoparticles within thermoresponsive poly(N-isopropylacrylamide) (pNIPAM) shells is presented and demonstrated. The layer-by-layer (LbL) strategy was used to provide the metal nanoparticles surface with vinyl functional groups, from which pNIPAM can be readily grown. This method can be applied to the encapsulation of gold nanoparticles within a wide range of sizes, shapes and capping agents. We demonstrate here the encapsulation of cetyltrimethyl ammonium bromide (CTAB) stabilized Au spheres and poly(vinylpyrrolidone) (PVP) stabilized Au decahedra and nanostars, thereby exemplifying the fabrication of nanocomposites with tailored localized surface plasmon resonances (LSPR). Additionally, the total diameter of the Au@pNIPAM microgels, as well as the number of encapsulated metal cores, was varied through controlled addition of sodium dodecyl sulfate (SDS). The optical response could be thus modulated through temperature-induced local changes of the refractive index around the gold cores, as well as by plasmon coupling between metal nanoparticles located within the same microgel.

Dihydromyricetin (DHM) dramatically improved the quality of life for Streptozotocin (STZ)‐induced diabetic rats and significantly increased the activity of antioxidant enzymes in the liver. Moreover, DHM successfully ameliorated diabetes‐induced liver damage by suppression of apoptosis in the liver, as indicated by the decreased levels of Bax and cleaved caspase‐3. In diabetic rats, the levels of tumor necrosis factor‐ α and interleukin‐1 β in the liver were significantly increased. However, the administration of DHM (100–400 mg/kg/day) for 6 weeks restored the cytokine levels to their normal values in a dose‐dependent manner in diabetic rats by the regulation of nuclear factor‐kappa B signaling pathway. In addition, DHM significantly induced 5′ AMP‐activated protein kinase (AMPK) phosphorylation and decreased MyD88, TLR4, p38, GSK‐3 β protein expression levels in the liver of diabetic rats. In conclusion, DHM could improve STZ‐induced liver impairment by preventing oxidative stress, apoptosis, and inflammation.