Search

This review explores the antioxidant properties of oak (Quercus sp.) extracts and their potential application in preventing oxidative rancidity in food products. Oxidative rancidity negatively impacts food quality, causing changes in color, odor, and flavor and reducing the shelf life of products. The use of natural antioxidants from plant sources, such as oak extracts, has gained increasing interest due to potential health concerns associated with synthetic antioxidants. Oak extracts contain various antioxidant compounds, including phenolic acids, flavonoids, and tannins, which contribute to their antioxidative capacity. This review discusses the chemical composition of oak extracts, their antioxidative activity in different food systems, and the safety and potential challenges related to their application in food preservation. The potential benefits and limitations of using oak extracts as an alternative to synthetic antioxidants are highlighted, and future research directions to optimize their application and determine their safety for human consumption are suggested.

Background: Azacitidine (AZA) is approved for the treatment of high-risk chronic myelomonocytic leukemia (CMML) of myelodysplastic (MD) subtype. Data of response rates using the specific response criteria for this disease are scarce. The aim of this study was to evaluate the response to AZA in patients diagnosed with CMML from the Spanish Registry of Myelodysplastic Syndromes (MDS) applying the overlap myelodysplastic/myeloproliferative neoplasms (MDS/MPN) response criteria. Methods: We retrospectively studied 91 patients with CMML treated with at least one cycle of AZA from the Spanish Registry of MDS. As it was a real-world study, the response rate was evaluated between cycle 4 and 6, applying the MDS/MPN response criteria Findings: The overall response rate at cycle 4-6 was 58%. Almost half of the patients achieved transfusion independence and one quarter showed clinical benefit, regardless of the CMML French-American-British (FAB) and World Health Organization (WHO) subtypes and CMML Specific Prognosis Scoring (CPSS) risk groups. Toxicity was higher in the MD-CMML subtype. Interpretation: In our series, most CMML patients achieved an overall response rate with AZA according to the overlap-MDS/MPN response criteria regardless of the CMML FAB and WHO subtypes and CPSS risk groups. Thus, AZA may also be a treatment option for patients with the myeloproliferative CMML subtype and those with a lower-risk CPSS, but symptomatic.

Salmonella can form biofilms that contribute to its resistance in food processing environments. Biofilms are a dense population of cells that adhere to the surface, creating a matrix composed of extracellular polymeric substances (EPS) consisting mainly of polysaccharides, proteins, and eDNA. Remarkably, the secreted substances, including cellulose, curli, and colanic acid, act as protective barriers for Salmonella and contribute to its resistance and persistence when exposed to disinfectants. Conventional treatments are mostly ineffective in controlling this problem; therefore, exploring anti-biofilm molecules that minimize and eradicate Salmonella biofilms is required. The evidence indicated that terpenes effectively reduce biofilms and affect their three-dimensional structure due to the decrease in the content of EPS. Specifically, in the case of Salmonella, cellulose is an essential component in their biofilms, and its control could be through the inhibition of glycosyltransferase, the enzyme that synthesizes this polymer. The inhibition of polymeric substances secreted by Salmonella during biofilm development could be considered a target to reduce its resistance to disinfectants, and terpenes can be regarded as inhibitors of this process. However, more studies are needed to evaluate the effectiveness of these compounds against Salmonella enzymes that produce extracellular polymeric substances.

The aim of the present study was to investigate the inhibitory mechanisms of quercetin against L. monocytogenes biofilm formation, by affecting secretion of polymeric substances (EPS) and spatio-temporal organization. The minimum concentration of quercetin inhibiting the establishment of bacterial biofilm was determined to be 0.8 mM; therefore, a lower concentration of the flavonoid (0.2 mM) was used in order to investigate its effect on cell attachment and EPS production on stainless steel and the spatio-temporal organization on glass, while avoiding bias of loss of cellular viability. In applying this concentration, reductions of 1.32 and 1.94 Log10 CFU/cm2 of initial adhesion and maximum cell density on stainless steel were observed on the test surfaces at 2 h (initial adhesion) and 24 h (maximum cell density), respectively. EPS on mature biofilms (24 h) was mainly composed by proteins (97.83%), followed by polysaccharides (2.03%) and DNA (0.14%). In addition, quercetin reduced total extracellular protein content by 41% compared with control; while, DNA and polysaccharide contents in biofilms were not affected. Also, relative to control, quercetin impaired surface colonization, early stages of biofilm formation and the development of a more complex architecture during its formation. This proved that quercetin inhibited the formation of L. monocytogenes biofilms by reducing initial attachment, the amount of extracellular proteins found in the EPS matrix and the overall spatio-temporal organization of L. monocytogenes.

Pectobacterium carotovorum causes soft rot in plant food due to its ability to synthesize exoenzymes, and secrete polymeric substances to form biofilm; in addition, this aggregated form of bacteria creates resistance during disinfection. However, the biofilm formation process and composition of P. carotovorum is still uncharacterized, which is important to design more efficient disinfection procedures. Among the actual disinfection trends, the use of plant compounds has deserved plenty of attention; being carvacrol, a monoterpene constituent of oregano essential oil that is known to reduce biofilm formation of many bacteria. Therefore, the objective of this study was to evaluate the effect of carvacrol against biofilm development of P. carotovorum, EPS composition, bacterial surface charge, adhesion potential and motility. Minimal planktonic inhibitory and bactericidal concentrations of carvacrol were 2.66 and 3.99 mM; whereas, concentrations of 1.33 and 3.99 mM were needed to inhibit and eradicate biofilm, respectively. Carvacrol at 0.66 mM was chosen as the concentration to evaluate its effect on EPS secretion, motility and surface physicochemical characteristics without affecting the viability of planktonic cells. It was shown that carvacrol at this concentration decreased bacterial surface charge (−2.15 mV), adhesion potential (−1.5 mJ/m2) and swimming motility of P. carotovorum (48.2 mm) compared with untreated bacteria. In addition, polysaccharides were the main components of the biofilm matrix of P. carotovorum, whose synthesis was inhibited by the presence of carvacrol. These results demonstrated that carvacrol could be effective against P. carotovorum biofilm formation and eradication, reducing adhesion, motility and synthesis of polysaccharides.

Cold dark matter (CDM) has shown to be an excellent candidate for the dark matter (DM) of the Universe at large scales, however it presents some challenges at the galactic level. The scalar field dark matter (SFDM), also called fuzzy, wave, Bose-Einstein condensate or ultra-light axion DM, is identical to CDM at cosmological scales but different at the galactic ones. SFDM forms core halos, it has a natural cut-off in its matter power spectrum and it predicts well-formed galaxies at high redshifts. In this work we reproduce the rotation curves of high-resolution low surface brightness (LSB) and SPARC galaxies with two SFDM profiles: (1)~The soliton+NFW profile in the fuzzy DM (FDM) model, arising empirically from cosmological simulations of real, non-interacting scalar field (SF) at zero temperature, and (2)~the multistate SFDM (mSFDM) profile, an exact solution to the Einstein-Klein-Gordon equations for a real, self-interacting SF, with finite temperature into the SF potential, introducing several quantum states as a realistic model for a SFDM halo. From the fits with the soliton+NFW profile, we obtained for the boson mass $0.212< m_��/(10^{-23} \mathrm{eV}/c^2), 24 pages, 11 figures. Accepted for publication in MNRAS

This study evaluated the effect of grape stems extracts on motility, surface energy and adhesion of L. monocytogenes to stainless steel and polypropylene surfaces. Stem extracts from Red Globe grapes showed a higher content of total phenolics than Carignan stems. Moreover, both extracts reduced adhesion of Listeria to stainless steel (0.77-2.22 log CFU cm-2) and polypropylene (0.71-2.38 log CFU cm-2) and completely inhibited bacterial motility at 4.5 and 5 mg mL-1 of Red Globe and Carignan extracts, respectively. Similarly, both extracts affected the surface energy of bacteria and modified the adhesion potential of L. monocytogenes to both surfaces. Otherwise, caffeic, ferulic and gallic acids, catechin and rutin, presented in both extracts, reduced adhesion of L. monocytogenes to stainless steel (0.39-2.04 log CFU cm-2) at 10 mM. In conclusion, Red Globe and Carignan grape stem extracts inhibited adhesion of L. monocytogenes to stainless steel and polypropylene surfaces by inhibiting motility and modifying its adhesion potential.

Aims To study the individual and combined contribution of catechin, protocatechuic and vanillic acids to inhibit the adhesion of uropathogenic Escherichia coli (UPEC) on the surface of silicone catheters. Methods and Results The adhesion of UPEC to silicone catheters during the exposure to nonlethal concentrations of phenolic compounds was measured, as well as changes in motility, presence of fimbriae, extra-cellular polymeric substances, surface charge, hydrophobicity and membrane fluidity. The phenolic combination reduced 26–51% of motility, 1 log CFU per cm2 of adhered bacteria and 20–40% the carbohydrate and protein content in the biofilm matrix. Curli fimbriae, surface charge and cell hydrophobicity were affected to a greater extent by the phenolic combination. In the mixture, vanillic acid was the most effective for reducing bacterial adhesion, extra-polymeric substance production, motility, curli fimbriae and biofilm structure. Notwithstanding, protocatechuic acid caused major changes in the bacterial cell surface properties, whereas catechin affected the cell membrane functionality. Conclusion Catechin, protocatechuic and vanillic acids have different bacterial cell targets, explaining the synergistic effect of their combination against uropathogenic E. coli. Significance and Impact of Study This study shows the contribution of catechin, protocatechuic and vanillic acids in producing a synergistic mixture against the adhesion of uropathogenic E. coli on silicone catheters. The action of catechin, vanillic and protocatechuic acids included specific contributions of each compound against the E. coli membrane’s integrity, motility, surface properties and production of extracellular polymeric substances. Therefore, the studied mixture of phenolic compounds could be used as an antibiotic alternative to reduce urinary tract infections associated with silicone catheters.

Pathogenic bacteria use Quorum sensing (QS) to regulate the expression of virulence factors involved in plant tissue infection. Some of these factors are the production of biofilm, hydrolytic enzymes, toxins, and plasmids; therefore, the interruption of this system could be a useful tool to control plant tissue infections. This review analyzes the potential treatments to interrupt QS and control the infection of plant tissues.

The objective of this study was to evaluate the effect of combining catechin, protocatechuic, and vanillic acids against planktonic growing, adhesion, and biofilm eradication of uropathogenic Escherichia coli (UPEC), as well as antioxidant agents. The minimum inhibitory concentrations (MIC) of protocatechuic, vanillic acids and catechin against the growth of planktonic bacteria were 12.98, 11.80, and 13.78 mM, respectively. Mixing 1.62 mM protocatechuic acid + 0.74 mM vanillic acid + 0.05 mM catechin resulted in a synergistic effect acting as an MIC. Similarly, the minimum concentrations of phenolic compounds to prevent UPEC adhesion and biofilm formation (MBIC) were 11.03 and 7.13 mM of protocatechuic and vanillic acids, respectively, whereas no MBIC of catechin was found. However, combinations of 1.62 mM protocatechuic acid + 0.74 mM vanillic acid + 0.05 mM catechin showed a synergistic effect acting as MBIC. On the other hand, the minimum concentrations to eradicate biofilms (MBEC) were 25.95 and 23.78 mM, respectively. The combination of 3.20 mM protocatechuic acid, 2.97 mM vanillic acid, and 1.72 mM catechin eradicated pre-formed biofilms. The antioxidant capacity of the combination of phenolics was higher than the expected theoretical values, indicating synergism by the DPPH&bull, ABTS, and FRAP assays. Effective concentrations of catechin, protocatechuic, and vanillic acids were reduced from 8 to 1378 times when combined. In contrast, the antibiotic nitrofurantoin was not effective in eradicating biofilms from silicone surfaces. In conclusion, the mixture of phenolic compounds was more effective in preventing cell adhesion and eradicating pre-formed biofilms of uropathogenic E. coli than single compounds and nitrofurantoin, and showed antioxidant synergy.

Plant extracts have the potential to be used as food additives, however, their use have been limited by causing undesirable changes in the sensory attributes of foods. We characterized the mango seed extract as a preserving agent for fresh-cut mangoes. We established the maximum concentration of extract that, while increasing the antioxidant activity, and limiting microbial contamination of the fruit, did not negatively affect fruit sensory acceptability. The extract contained 277.4 g gallic acid equivalent (GAE)/kg dw (dry weight) of polyphenols and 143.7 g quercetin equivalent (QE)/kg dw of flavonoids. Antioxidant capacity values were 2034.1 and 4205.7 &mu, mol Trolox equivalent (TE)/g against 2,2-diphenyl-1-picryl-hydrazyl (DPPH) and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS) radicals, respectively. Chromatographic analysis revealed the presence of gallic and chlorogenic acids. The extract (16 g/L) inhibited the growth of Escherichia coli, Salmonella Typhimurium, Staphylococcus aureus and Listeria monocytogenes. The highest concentration with sensory acceptability was 6.25 g/L. At such concentration, the extract preserved fresh-cut fruits, increasing polyphenols (0.427 g GAE/kg fw (fresh weight)), flavonoid content (0.234 g QE/kg fw) and antioxidant activity (DPPH = 2.814 and ABTS = 0.551 mol TE/kg fw). It also reduced inoculated bacteria (range: 5.50 &times, 103 to 1.44 &times, 105 colony forming units (CFU)/g). These results showed the importance of considering consumer acceptability to determine the effective concentration of plant extracts as additives.

The effect of the application of ethanolic extract of “Haden” mango seeds to increase the antioxidant and antimicrobial capacity of fresh-cut mango flesh was evaluated. Phenolic HPLC analysis revealed that gallic acid was the major identified compound in the ethanolic extract (586.68 mg/g). Fresh-cut mango was treated for immersion within the ethanolic extract, packed and stored at 5℃ during 15 days. The content of phenolic compounds, antioxidant capacity and microbial growth of the treated mango were evaluated during the storage. Compared with the controls the treated fruit presented the highest content of the total phenolic (7.4 times), flavonoids (3.1 times), and antioxidant capacity DPPH·, TEAC and ORAC (2.9, 2.3 and 2.8 times, respectively), and showed a microbial reduction of 80% of mesophilic plate count and 97% of total molds. This study demonstrates the potential of phenolic compounds derived from mango seed as antimicrobials and antioxidants.

espanolObjetivo. Presentar la experiencia de iniciacion a la investigacion con estudiantes de medicina mediante asignaturas optativas: ‘Proyectos de investigacion de grado’ (1, 2 y 3). Sujetos y metodos. Han participado estudiantes de segundo, tercero y cuarto ano de los cursos academicos 2011-2012 a 2017-2018 que se matricularon sucesivamente en ‘Proyectos 1’ (identificacion del tema, documentacion y elaboracion de hipotesis y objetivos), ‘Proyectos 2’ (diseno metodologico y adquisicion de datos) y ‘Proyectos 3’ (divulgacion cientifica). Cada grupo, de 2-4 estudiantes, trabajo bajo la direccion de un tutor, realizo presentaciones y elaboro un manuscrito sobre su actividad. En ‘Proyectos 3’, presentaron un poster con la actividad de los tres cursos que se expuso en una jornada monografica. La evaluacion de la satisfaccion de los estudiantes se realizo mediante una encuesta. Resultados. En total, 546 estudiantes han iniciado la experiencia en ‘Proyectos 1’, de los que el 43,9% la completan. El numero de tutores participantes ha sido de 83. Se han abordado 195 temas de investigacion, de los que el 59% son de investigacion clinica, el 31% de investigacion fundamental y el 10% de otros. Las calificaciones obtenidas han sido superiores a 9 puntos sobre 10. La encuesta resalta que los estudiantes valoran el papel de los tutores y el potencial formativo de la actividad. Conclusion. El diseno de los cursos permite que el estudiante tome contacto con diferentes aspectos del proceso de investigacion, actividad que consideran gratificante y apropiada a su formacion como medico. EnglishAim. To present the experience of an initiation in to research for medical students through optional courses: ‘Research Projects of Degree’ (1, 2, and 3). Subjects and methods. Medical students in their second, third, and fourth year from the academic years 2011-2012 to 2017-2018, enrolled consecutively in the subjects: ‘Projects 1’, identification of the topic, documentation and elaboration of hypotheses and objectives; ‘Projects 2’, methodological design and acquisition of data; and ‘Projects 3’, scientific disclosure. Each group, of 2-4 students, did a research project under the supervision of a tutor; the research project was presented orally and on paper. In ‘Projects 3’, students made a poster about the activities performed during the three courses, posters were shown in a monographic exhibition. Evaluation of student satisfaction was carried out through a survey. Results. A total of 546 students started the experience in ‘Projects 1’, of which 43.9% completed it. The number of participating tutors was 83, addressing 195 research topics, of which 59% were clinical research, 31% fundamental research and 10% were termed others. The scores obtained in these courses were higher than 9 points out of 10. The survey highlights the important role of advisers and the training potential of the activity. Conclusion. The design of the course allows the students to be in contact with different aspects of the biomedical research processes. Students considered the activity rewarding, useful, and appropriate to their training as a physician.

In the pursuit of a general formulation for a modified gravitational theory at the non-relativistic level and as an alternative to the dark matter hypothesis, we construct a model valid over a wide variety of astrophysical scales. Through the inclusion of Milgrom's acceleration constant into a gravitational theory, we show that very general formulas can be constructed for the acceleration felt by a particle. Dimensional analysis shows that this inclusion naturally leads to the appearance of a mass-length scale in gravity, breaking its scale invariance. A particular form of the modified gravitational force is constructed and tested for consistency with observations over a wide range of astrophysical environments, from solar system to extragalactic scales. We show that over any limited range of physical parameters, which define a specific class of astrophysical objects, the dispersion velocity of a system must be a power law of its mass and size. These powers appear linked together through a natural constraint relation of the theory. This yields a generalised gravitational equilibrium relation valid for all astrophysical systems. A general scheme for treating spherical symmetrical density distributions is presented, which in particular shows that the fundamental plane of elliptical galaxies, the Newtonian virial equilibrium, the Tully-Fisher and the Faber-Jackson relations, as well as the scalings observed in local dwarf spheroidal galaxies, are nothing but particular cases of that relation when applied to the appropriate mass-length scales. We discuss the implications of this approach for a modified theory of gravity and emphasise the advantages of working with the force, instead of altering Newton's second law of motion, in the formulation of a gravitational theory.

Some quantum-cosmic scaling relations indicate that the MOND acceleration parameter a_0 could be a fundamental quantity ruling the self-gravitating structures, ranging from stars and globular clusters up to superclusters of galaxies and the whole observed universe. We discuss such coincidence relations starting from the Dirac quantization condition ruling the masses of primordial black holes., Comment: 6 pages

We show that the Modified Newtonian Dynamics (MOND) regime can be fully recovered as the weak-field limit of a particular theory of gravity formulated in the metric approach. This is possible when Milgrom's acceleration constant is taken as a fundamental quantity which couples to the theory in a very consistent manner. As a consequence, the scale invariance of the gravitational interaction is naturally broken. In this sense, Newtonian gravity is the weak-field limit of general relativity and MOND is the weak-field limit of that particular extended theory of gravity., To appear in the proceedings of the 2011 Spanish Relativity Meeting (ERE2011) held in Madrid, Spain, 4 pages

We show that the Modified Newtonian Dynamics (MOND) regime can be fully recovered as the weak-field limit of a particular theory of gravity formulated in the metric approach. This is possible when Milgrom's acceleration constant is taken as a fundamental quantity which couples to the theory in a very consistent manner. As a consequence, the scale invariance of the gravitational interaction is naturally broken. In this sense, Newtonian gravity is the weak-field limit of general relativity and MOND is the weak-field limit of that particular extended theory of gravity. We also prove that a Noether's symmetry approach to the problem yields a conserved quantity coherent with this relativistic MONDian extension., Comment: 7 pages, minor corrections to the original version. Accepted for publication in The European Physical Journal C

Dwarf spheroidal (dSph) galaxies are the smallest galactic systems known. Also, under standard gravity, they are the most dark matter dominated systems known in astrophysics. The local sample of dSph satellites of the Milky Way comprise some two dozen systems, ranging from a few million, down to just a few thousand solar masses in stellar content, for the recently discovered ones. High quality observations of their stellar kinematics now allow detailed inferences of their structural and dynamical properties. We perform a modeling of the gravitational equilibrium configurations for a sample of he best studied dSphs under MOND, and find that a satisfactory description is obtained, without the need to invoke the presence of dark matter or any tidal effects, for a particular interpolation function, valid at this regime. We find also that the now well established scalings of the structural properties of these systems are naturally accounted for, while they require fine tuning under the dark matter hypothesis. In particular we find a previously unrecognized scaling between the inferred mass to light ratio of a particular dSph, with the age of most recent star formation episode for the system. Again, a trait which emerges naturally under any modified gravity scheme, and which appears as an unexplained coincidence under the dark matter hypothesis.

espanolLos pacientes con lesion pulmonar aguda o sindrome de distres respiratorio agudo (SDRA) ingresados en unidades de cuidados intensivos (UCI) presentan alteraciones neuropsicologicas que en la mayoria de los casos se extienden mas alla de la fase aguda, acarreando importantes deficits en su calidad de vida. El objetivo de la presente puesta al dia es profundizar en el analisis de la compleja interaccion entre el pulmon y el cerebro en el enfermo critico sometido a ventilacion mecanica. Inicialmente se describen las alteraciones neuropsicologicas asociadas tanto durante la fase aguda de estancia en la UCI como al alta hospitalaria. En un segundo apartado se analiza la interaccion pulmon-cerebro durante la ventilacion mecanica y, finalmente, se explora la etiologia y los mecanismos que dan lugar a las alteraciones neurologicas que se observan en estos pacientes. El manejo del paciente critico requiere de una vision integradora enfocada a minimizar los efectos deletereos a corto, medio o largo plazo. EnglishPatients with acute lung injury or acute respiratory distress syndrome (ARDS) admitted to the ICU present neuropsychological alterations, which in most cases extend beyond the acute phase and have an important adverse effect upon quality of life. The aim of this review is to deepen in the analysis of the complex interaction between lung and brain in critically ill patients subjected to mechanical ventilation. This update first describes the neuropsychological alterations occurring both during the acute phase of ICU stay and at discharge, followed by an analysis of lung-brain interactions during mechanical ventilation, and finally explores the etiology and mechanisms leading to the neurological disorders observed in these patients. The management of critical patients requires an integral approach focused on minimizing the deleterious effects over the short, middle or long term.

European Discussion Meeting on Polymer Physics; Semicrystalline Polymers: Structure Formation and Properties, Alemania, 24 September 2003, he microhardness H of multilayered poly(ethylene terephthalate) (PET)/polycarbonate (PC) films, produced by continuous layer multiplying coextrusion has been determined. These materials present rather uniform laminates up to thousands of layers in the micrometre and submicrometre range. The micromechanical properties have been investigated as a function of layer thickness of the single polymer components, the total number of layers, the film thickness and the influence of heat treatment. The microhardness of the microlayered structure has also been determined across the profile in the parallel direction to the packing of the layers. The hardness in the vicinity of the PET/PC phases has been examined. Results reveal that the influence of the interphase on the H values for the samples with a large number of layers is rather small. The most important parameter in determining the final hardness of the multilayered films is the ratio of the penetration depth to the thickness of the layer. Upon heating, a microhardness increase is observed as a consequence of a double contribution: the crystallization of the PET layers, on the one hand, and the physical ageing of the PC zones on the other.

We have experimentally determined the absorption coefficient of CO/sub 2/ using the 3P(2) line emitted by an HF laser, as a function of the gas temperature up to 700/spl deg/K, while keeping its pressure as a parameter. The measurements were compared with a theoretical model for the absorption which takes into account the high monochromaticity of the source and the detuning of the HF laser lines with respect to the CO/sub 2/ absorption lines central wavelengths. A set of values was thus obtained for the A Einstein coefficient of the transitions given by (O O/sup 0/0)/spl rarr/(O 2/sup 0/1; 1 1/sup 1/ 1)/sub I,II/, (10/sup 0/ O; O 2/sup 0/ O)/sub I,II//spl rarr/(O 4/sup 0/1; 1 2/sup 0/1; 2 O/sup 0/1)/sub I,II,III/ and (01/sup 1/ O)/spl rarr/(1 1/sup 1/ 1; O 3/sup 1/ 1)/sub I,II/, in such a way that said values allowed, the coincidence between the experimental results and those predicted by the theoretical model. >