Partial Characterization and Immunomodulatory Effects of Exopolysaccharides from Streptococcus thermophilus SBC8781 during Soy Milk and Cow Milk Fermentation.

The immunomodulatory properties of exopolysaccharides (EPSs) produced by Streptococcus thermophilus have not been explored in depth. In addition, there are no comparative studies of the functional properties of EPSs produced by streptococci in different food matrices. In this work, EPSs from S. thermophilus SBC8781 were isolated after soy milk (EPS-s) or cow milk (EPS-m) fermentation, identified, and characterized in their abilities to modulate immunity in porcine intestinal epithelial cells. Fresh soy milk and cow milk were inoculated with S. thermophilus SBC8781 (7 log CFU/mL) and incubated at 37 °C for 24 h. The extraction of EPSs was performed by the ethanol precipitation method. Analytical techniques, including NMR, UV-vis spectroscopy, and chromatography, identified and characterized both biopolymer samples as polysaccharides with high purity levels and similar Mw. EPS-s and EPS-m had heteropolysaccharide structures formed by galactose, glucose, rhamnose, ribose, and mannose, although with different monomer proportions. On the other hand, EPS-s had higher quantities of acidic polymer than EPS-m. The biopolymer production of the SBC8781 strain from the vegetable culture broth was 200-240 mg/L, which was higher than that produced in milk, which reached concentrations of 50-70 mg/L. For immunomodulatory assays, intestinal epithelial cells were stimulated with 100 µg/mL of EPS-s or EPS-m for 48 h and then stimulated with the Toll-like receptor 3 agonist poly(I:C). EPS-s significantly reduced the expression of IL-6, IFN-ß, IL-8, and MCP-1 and increased the negative regulator A20 in intestinal epithelial cells. Similarly, EPS-m induced a significant reduction of IL-6 and IL-8 expressions, but its effect was less remarkable than that caused by EPS-s. Results indicate that the structure and the immunomodulatory activity of EPSs produced by the SBC8781 strain vary according to the fermentation substrate. Soy milk fermented with S. thermophilus SBC8781 could be a new immunomodulatory functional food, which should be further evaluated in preclinical trials.

Structural characterization of a homopolysaccharide produced by Weissella cibaria FMy 2-21-1 and its potential application as a green corrosion inhibiting film.

Steel corrosion is a global issue that affects safety and the economy. Currently, the homopolysaccharide (HoPS) structure of a novel lactic acid bacterium (LAB) is under study, as well as its application as a green corrosion inhibitor. Weissella cibaria FMy 2-21-1 is a LAB strain capable of producing HoPS in sucrose enriched media. The isolated and purified HoPS was characterized by different spectroscopic analyses as a linear α-1,6 dextran adopting a random coil conformation, with high molecular weight and extended size in water. The polysaccharide showed a semi-crystalline organization, which is a requirement for film formation. Its biocoating showed a grainy network structure, with a slightly lesser hydrophobic role in the aqueous environment than in the ionic one. The electrochemical measurements of the steel-HoPS coating showed that the biopolymer layer acts as an anodic-type corrosion inhibitor, with high resistance to corrosion by water and with chloride ions which prevent pitting, a corrosion process typical of bare steel. Few reports have cited the application of LAB HoPS as corrosive coating inhibitors. This work is the first to explore the influence of a structurally characterized dextran from Weissella cibaria strain as a potential steel corrosion inhibitor in ionic environments.

Challenging social media threats using collective well-being-aware recommendation algorithms and an educational virtual companion.

Social media have become an integral part of our lives, expanding our interlinking capabilities to new levels. There is plenty to be said about their positive effects. On the other hand, however, some serious negative implications of social media have been repeatedly highlighted in recent years, pointing at various threats to society and its more vulnerable members, such as teenagers, in particular, ranging from much-discussed problems such as digital addiction and polarization to manipulative influences of algorithms and further to more teenager-specific issues (e.g., body stereotyping). The impact of social media-both at an individual and societal level-is characterized by the complex interplay between the users' interactions and the intelligent components of the platform. Thus, users' understanding of social media mechanisms plays a determinant role. We thus propose a theoretical framework based on an adaptive "Social Media Virtual Companion" for educating and supporting an entire community, teenage students, to interact in social media environments in order to achieve desirable conditions, defined in terms of a community-specific and participatory designed measure of Collective Well-Being (CWB). This Companion combines automatic processing with expert intervention and guidance. The virtual Companion will be powered by a Recommender System (CWB-RS) that will optimize a CWB metric instead of engagement or platform profit, which currently largely drives recommender systems thereby disregarding any societal collateral effect. CWB-RS will optimize CWB both in the short term by balancing the level of social media threats the users are exposed to, and in the long term by adopting an Intelligent Tutor System role and enabling adaptive and personalized sequencing of playful learning activities. We put an emphasis on experts and educators in the educationally managed social media community of the Companion. They play five key roles: (a) use the Companion in classroom-based educational activities; (b) guide the definition of the CWB; (c) provide a hierarchical structure of learning strategies, objectives and activities that will support and contain the adaptive sequencing algorithms of the CWB-RS based on hierarchical reinforcement learning; (d) act as moderators of direct conflicts between the members of the community; and, finally, (e) monitor and address ethical and educational issues that are beyond the intelligent agent's competence and control. This framework offers a possible approach to understanding how to design social media systems and embedded educational interventions that favor a more healthy and positive society. Preliminary results on the performance of the Companion's components and studies of the educational and psychological underlying principles are presented.

Interrelación Entre Ortodoncia y Periodoncia en Periodonto Reducido. Estabilidad Periodontal Tras 6 Años de Seguimiento / Interrelation Between Orthodontics and Periodontics in Reduced Periodontium. Periodontal Stability After 6 Years of Follow-up

RESUMEN: En pacientes con periodontitis, la migración dentaria patológica es una consecuencia de la pérdida de soporte periodontal. El siguiente reporte de caso aborda el tratamiento periodontal y ortodóncico de una paciente con periodontitis y migración dentaria patológica. El protocolo utilizado fue el protocolo de la Unidad de Ortodoncia y Periodoncia de la Facultad de Odontología de la Universidad de Chile. La estabilidad periodontal se ha mantenido por al menos 6 años luego de finalizado el tratamiento de ortodoncia logran-do funcionalidad y estética de la dentición natural.

ABSTRACT: In patients with periodontitis, pathologic tooth migration is a consequence of loss of periodontal support. The following case report addresses the periodontal and orthodontic treatment of a patient with periodontitis and pathologic tooth migration. The protocol used was the protocol of the Orthodontics and Periodontics Unit of the Faculty of Dentistry of the University of Chile. The periodontal stability has been maintained for at least 6 years after the end of orthodontic treatment, achieving functionality and aesthetics of the natural dentition.

Techno-functional properties of HoPS from lactic acid bacteria of different origins as potential food additives.

Homopolysaccharides (HoPS) produced by lactic acid bacteria (LAB) are highly versatile, biocompatible and safe compounds. In this work, six HoPS from different species of Weisella and Leuconostoc were identified as thermally stable dextrans, with endothermic crystalline deformations between 214 and 239 °C. These dextrans proved to have greater solubility and capacities to retain water and oil than similar polymers in other reports. Furthermore, a surface morphology study presented cubic grumps, stratify mesh with irregular grumps, and highly compact filaments. Assays in vitro revealed moderate antioxidant, browning and foaming activities as well as technological properties, such as anti-syneresis, emulsifying and flocculating activities, even at low concentrations. Taking into account bipolymers' microstructure, functionalities and performance in both, aqueous and hydrophobic matrixes, plus their capacity to maintain themselves at elevated temperatures, we consider these HoPS beneficial and natural food additives.

Estudio comparativo de la actividad analgésica de clonixinato de lisina y naproxeno sódico en el control del dolor postoperatorio en cirugía oral / Comparative study of analgesic activity of lisine clonixinate and sodic naproxene in postsurgical pain control after oral surgery

El objetivo de la presente investigación fue comparar la actividad analgésica de clonixinato de lisina con el naproxeno sódico en el dolor postoperatorio subsecuente a la cirugía oral. Utilizando el método doble-ciego, dosis únicas de clonixinato de lisina 125 mg. o de naproxeno sódico 550 mg. se administraron por selección al azar a 92 pacientes con dolor postoperatorio después de efectuar extracciones de terceros molares incluidos. Durante un periodo de control de 4 horas posterior a la ingestión oral de cada una de las medicaciones estudiadas, se evaluaron en cada paciente