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Introduction: Ocular trauma is defined as a trauma caused by blunt or penetrating mechanisms on the eyeball and its peripheral structures, causing damage with different degrees of affection with temporary or permanent visual function compromise. Ocular trauma is a major cause of preventable blindness worldwide; it constitutes 7% of all corporal injury and 10% to 15% of all eye diseases. Regenerative medicine research has opened up the possibility to use stem cells as a source of cell replacement, so that experimental studies on embryonic stem cells and bone marrow stem cells have been carried out. In this study, we analyzed the histopathological and spectroscopic changes in ocular tissue with trauma, treated with mouse pluripotent stem cells. Methods: Firstly, mouse embryonic stem cells were seeded. Subsequently, the obtained cells were implanted in a murine model of scleral and retinal damage at the first, second, and fourth weeks post-trauma. At week 12 post-trauma, the eyes were enucleated for histopathologic study (inflammatory response and histological integrity) and spectroscopic analysis by Fourier transform infrared spectroscopy in the attenuated total reflection configuration. Data were analyzed by one-way analysis of variance. Results: Histopathological results showed that the experimental groups treated with stem cells presented a decrease in the inflammatory response, and the histological integrity was restored, which contrasted with the experimental group treated with saline solution. Moreover, in the spectroscopic analysis, characteristic bands of biological samples were observed in all tissues, highlighting in healthy tissues the presence of C = O bond at 1,745 cm-1, which was not observed in the injured and treated tissues. Also, the absorption spectrum of the tissues treated with embryonic stem cells showed bands whose intensity was high at around 1,080 to 1,070 cm-1. It has been reported that these bands are characteristic of pluripotent stem cells. Conclusions: The implant of embryonic stem cells could be a useful therapeutic treatment after traumatic eye injuries or many other eye diseases to reduce the inflammatory response and restore histological integrity. Furthermore, the spectroscopic technique could be used as a complementary technique for detecting stem cell incorporation into various tissues. [ABSTRACT FROM AUTHOR]

The genus Capsicum provides antioxidant compounds, such as phenolics and carotenoids, into the diet. In Mexico, there is a wide diversity of species and varieties of chilli peppers, a fruit which has local cultural and gastronomic importance. In the present study, the relationship of the carotenoid and phenolic profiles with the RAPD fingerprint of three different commercial cultivars of chilli peppers of seven regions of Mexico was investigated. Through RAPD, the species of chilli were differentiated by means of different primers (OPE-18, MFG-17, MFG-18, C51, and C52). The genetic distance found with OPE 18 was in the order of 2.6. The observed differences were maintained when the chromatographic profile of carotenoids, and the molecular markers were analyzed, which suggest a close relationship between carotenoids and the genetic profile. While the chromatographic profile of phenols and the molecular markers were unable to differentiate between genotypes of chilli peppers. In addition, by using infrared spectroscopy and statistical PCA, differences explained by geographic origin were found. Thus, this method could be an alternative for identification of chilli species with respect to their geographic origin. [ABSTRACT FROM AUTHOR]

The genus Capsicum provides antioxidant compounds, such as phenolics and carotenoids, into the diet. In Mexico, there is a wide diversity of species and varieties of chilli peppers, a fruit which has local cultural and gastronomic importance. In the present study, the relationship of the carotenoid and phenolic profiles with the RAPD fingerprint of three different commercial cultivars of chilli peppers of seven regions of Mexico was investigated. Through RAPD, the species of chilli were differentiated by means of different primers (OPE-18, MFG-17, MFG-18, C51, and C52). The genetic distance found with OPE 18 was in the order of 2.6. The observed differences were maintained when the chromatographic profile of carotenoids, and the molecular markers were analyzed, which suggest a close relationship between carotenoids and the genetic profile. While the chromatographic profile of phenols and the molecular markers were unable to differentiate between genotypes of chilli peppers. In addition, by using infrared spectroscopy and statistical PCA, differences explained by geographic origin were found. Thus, this method could be an alternative for identification of chilli species with respect to their geographic origin. [ABSTRACT FROM AUTHOR]

Zika fever is commonly perceived as a mild illness; however, often is linked to congenital Zika syndrome in newborns and Guillain–Barré syndrome in adults. The etiological agent, Zika virus, is a globally distributed arbovirus, frequently prevalent in tropical and humid climates. Conventional laboratory identification relies on real-time reverse transcription polymerase chain reaction (RT-PCR), a standard method requiring specialized infrastructure and technical training. To address these challenges, this research introduces the development of a nano immunosensor based on gold nanoparticles (AuNPs), for Zika virus biorecognition, assessed through Fourier-transform infrared spectroscopy (FTIR). The study further identifies signals associated with specific functional groups of viral envelopes. Ultra-high-resolution scanning electron microscopy (SEM) demonstrates the biorecognition of viral particles. Given the morphological, biochemical, and immunogenic resemblance between Zika and dengue viruses, this nano immunosensor is proficient in detecting dengue virus as well. Moving to the analysis phase, FTIR signals obtained after nano immunosensor–virus interaction were processed by principal component analysis (PCA). This achieved adequate discrimination between both viruses in key spectral regions: phospholipids, esters, and glycerides (1755–1726 cm−1), proteins (1683–1500 cm−1, 1328–1275 cm−1), and carbohydrates (1134–993 cm−1). These results underscore the utility of the AuNP-based nano immunosensor for identifying and discriminating between Zika and dengue viruses, offering a viable alternative in the diagnosis of these pathogenic agents. [ABSTRACT FROM AUTHOR]

AbstractThe Flaviviridae family includes many medically relevant members, such as dengue, Zika, West Nile, and hepatitis C viruses, that produce hundreds of millions of infections annually. There is a close relationship between these infections and inflammation triggering as an important part of the host’s immune response and of pathogenesis. These inflammatory processes are mediated by the activation of multiprotein complexes known as inflammasomes. Several inflammasomes have been described which differ in their composition and their activating stimuli. The NLRP3 inflammasome is the most studied. Its activation begins by the recognition of pathogen-associated molecular patterns such as viral RNA, potassium efflux, calcium flux, increased reactive oxygen species; and culminates in the maturation and secretion of pro-inflammatory cytokines such as IL-1β and IL-18, and cell death by pyroptosis. This review summarizes the most relevant aspects of NLRP3 inflammasome activation in relevant flavivirus infections from clinical and laboratory studies in biological models. Understanding the activation, mounting, and regulation of the inflammatory response during viral infections is a poorly exploited area of opportunity for the development of efficient and safe treatment strategies, which could include NLRP3 inflammasome inhibition. [ABSTRACT FROM AUTHOR]

Background: Diverse plants respond differently to similar saline conditions. The aim of the current study was to determine the variation in the foliar contents of phenolic compounds, carotenoids, and proline, and the variation of the activities of catalase (CAT) and superoxide dismutase (SOD) of the edible and medicinal Physalis ixocarpa throughout three different times of exposure (24, 42, and 57 d) to three salinity levels (0, 90, and 120 mM NaCl). The specific effects of salt concentration and time of exposure were also assessed. Results: Proline increase was the only clearly salt-related response, evidencing its significant protective role in salinized P. ixocarpa under either short, medium, or chronic exposure. One phenolic acid, which increased up to 26.26 times its concentration (compared to control, under high salinity at the longest treatment) out of the eight compounds forming the phenolic profile of the species, and CAT and SOD, under 90 and 120 mM NaCl, respectively, and short and medium exposure, also made important contributions. Salt concentration mainly affected total phenolics, tannins, phenolic acids (PA), proline, and SOD, whereas exposure time mainly affected flavonoids, carotenoids, and CAT. Conclusions: The participation of the different protection mechanisms of P. ixocarpa against salinity is dynamic and complementary, and it is differentially modulated by the salt concentration and the time of exposure. Proline is the main mechanism for the species. The accurate chronic registration of the responses is needed to determine its adaptation potential to salt stress. The results have agronomic and food quality implications. [ABSTRACT FROM AUTHOR]

Chia (Salvia hispanica L.) flour seeds produce films with good barrier properties against water vapor and could be used as food packaging; however, their mechanical properties are poor, which limits their application. The incorporation of nanoparticles into natural polymers is a strategy used to improve the properties of films to increase their applications. Furthermore, nanoparticles can encapsulate antioxidant agents and generate active films. The objective of this study was to evaluate the influence of chia flour (4%-7%), glycerol (15%-25%), and chia extract-loaded chitosan nanoparticles (ChCNp) (0%-0.75%) on the physical, mechanical, barrier, structural and antioxidant properties of chia flour nanocomposite films. Chitosan nanoparticles loaded with antioxidant chia extract were synthesized by ionic gelation and incorporated into the films. The thickness, water vapor permeability, tensile strength, and antioxidant properties of the films were evaluated using a Box-Behnken experimental design. Structural analysis was conducted using the FTIR technique. The results of the ANOVA of the responses were adjusted to second and third order polynomial models obtaining determination coefficients of 0.96-0.99. The water vapor permeability of the films was 3.89 × 10-8-1.68 × 10-7 g mm/Pa s m2, tensile strength was 0.67-3.59 MPa and antioxidant activity was 57.12%- 67.84%. The variables presented different effects on the films. Increasing the chia seed flour concentration negatively affected the water vapor permeability but improved the tensile strength and the antioxidant capacity of the films. The increase in glycerol concentration caused the films to become brittle. The nanoparticles had a significant effect on the thickness of the films and improved their mechanical and antioxidant properties. However, they did not show an effect on barrier properties. The results demonstrate that it is possible to obtain nanocomposite films with antioxidant capacity from chia seed flour and with the incorporation of chitosan nanoparticles loaded with antioxidants. [ABSTRACT FROM AUTHOR]

Currently, the food industry is interested in using plant-based ingredients because they can improve the nutritional and technological properties of products while also providing health benefits. The application of these ingredients in food formulations is dependent on their techno-functional properties, so determining them is critical. Pea seeds (Pisum sativum L.) are a good source of nutrients such as starch, protein, and fiber, which could also be used as functional food ingredients. It has been reported that differences in nutritional content and functional properties of pea seeds are caused by environmental conditions, cultivation methods, and processing. In Mexico, in the Mixteca Alta region of Oaxaca, creole peas are cultivated using rainfed agriculture, and the seeds are harvested when the plant is completely dry. There are currently no studies that evaluate the composition and properties of the main components of pea seeds grown under the environmental conditions of this region. The objective of this work was to determine the proximal composition and techno-functional properties of flour (PF), starch (PS), and protein (PPI) isolated from dry creole seeds cultivated in the Mixteca Alta region of Oaxaca. Results were compared using ANOVA and Tukey’s test (p ≤ 0.05). Significant differences (p ≤ 0.05) were found in the proximal composition and the color of PF, PS, and PPI. The extracted starch contains 19.6 ± 1.3 % amylose. The granules were ellipsoidal in shape and measured 57.2 ± 11.0 mm in diameter. The FTIR spectra showed structural differences between the samples. Functional properties such as water absorption capacity, foam formation, and emulsifying capacity were significantly higher in PPI than in PF and PS (p ≤ 0.05). The results demonstrate that pea seeds grown in the Mixteca Alta region of Oaxaca can be an unconventional source of functional ingredients for the food industry. [ABSTRACT FROM AUTHOR]

Gold nanoparticles (AuNPs) have been used in a wide range of applications, conferring to bio-molecules diverse properties such as delivery, stabilization, and reduction of the adverse effects of drugs or plant extracts. Polyphenolic compounds from Bacopa procumbens (B. procumbens) (BP) can modulate proliferation, adhesion, migration, and cell differentiation, reducing the artificial scratch area in fibroblast cultures and promoting wound healing in an in vivo model. Here, chemically synthesized AuNPs conjugated with BP (AuNP-BP) were characterized using UV-Vis, ATR-FTIR, DLS, zeta-potential, and TEM analysis. The results showed an overlap of the FTIR spectra of the polyphenolic compounds from B. procumbens adhered to the surface of the AuNPs. UV-vis analysis indicated that the average size of the AuNP-BP was 28 nm, while DLS analysis showed a size of 44.58 nm and, by TEM, a size of 16.5 nm with an icosahedral morphology was observed. These measurements suggest an increase in the size of the nanoparticles after conjugation with BP, compared to the sizes of 9 nm, 44.51 nm, and 14.17 nm for the unconjugated AuNPs, respectively. Furthermore, the zeta potential of the AuNPs, which was originally −36.3 ± 12.3 mV shifted to −18.2 ± 7.02 mV after conjugation with BP, indicating improved stability of the nanoparticles. Enhancement of the wound healing effect was evaluated by morphometric, histochemical, and FTIR changes in a rat wound excision model. Results showed that the nanoconjugation process reduced the BP concentrations by 100-fold to have the same wound healing effect as BP alone. Besides, histological and FTIR spectroscopy analyses demonstrated that AuNP-BP treatment exhibited better macroscopical performance, showing a reduction in inflammatory cells and an increased synthesis and improved organization of collagen fibers. [ABSTRACT FROM AUTHOR]

Encapsulation of biostimulant metabolites has gained popularity as it increases their shelf life and improves their absorption, being considered a good alternative for the manufacture of products that stimulate plant growth and fruit production. Cell-free supernatants (CFS) were obtained from nine indole-3-acetic acid (IAA) producing bacterial strains. Stenotrophomonas maltophilia (PT53T) produced the highest concentration of IAA (15.88 μg/mL) after 48 h of incubation. CFS from this strain, as well as an IAA standard were separately encapsulated in chitosan microparticles (CS-MP) using the ionic gelation method. The CS-MP were analyzed by Fourier transform infrared spectroscopy (FTIR), showing absorption bands at 1641, 1547, and 1218 cm−1, associated with the vibrations of the carbonyl C=O, the N-H amine, and the bond between chitosan (CHI) and sodium tripolyphosphate (TPP). The effects of unencapsulated CFS, encapsulated CFS (EN-CFS), and encapsulated IAA standard (EN-IAA) on germination and growth of seven-day-old tomato (Solanum lycopersicum) seedlings were studied. Results showed that both EN-CFS and EN-IAA significantly (p < 0.05) increased seed germination rates by 77.5 and 80.8%, respectively. Both CFS and EN-IAA produced the greatest increase in aerial part length and fresh weight with respect to the treatment-free test. Therefore, it was concluded that the application of EN-CFS or EN-IAA could be a good option to improve the germination and growth of tomato seedlings. [ABSTRACT FROM AUTHOR]

A colloidal nano-immunosensor based on gold nanoparticles covered in their surface with protein A and the immunoglobulin anti-kidney injury molecule-1 was prepared and tested in human urine to identify a biomarker that diagnose acute kidney injury. The urine was obtained from patients with cancer treated with cisplatin, diagnosed with acute kidney injury, and from healthy individuals. Fourier-transform infrared spectroscopy analysis showed important spectral differences between both types of groups, primarily for the intervals from 1750 to 1500 cm−1 and from 1000 to 891 cm−1 where the amide I group (C = O) and the glycosylated functional groups of this protein absorb. The principal component analysis applied to the vibrational signals obtained with the nano-immunosensor allows adequate discrimination of urine from patients with acute kidney injury from samples from healthy individuals. The simplicity of the proposed method, from the preparation of the nano-immunosensor to the spectral and chemometric analysis, may make this method an interesting alternative to practically diagnose acute kidney injury using a small volume of urine. [ABSTRACT FROM AUTHOR]

Salmonella is one of the main microorganisms that causes food-borne illnesses worldwide, although there are standard procedures to determine its presence or absence in food samples. However, these methodologies are time consuming and cumbersome, so the development of devices that rapidly and accurately determine bacteria is necessary. Various materials have been used to construct these devices. Hydrogenated amorphous silicon carbide (a-SiC:H) is one of the least studied. Therefore, in the present work, self-assembled monolayers were applied on a-SiC:H thin films to determine Salmonella Typhimurium ATCC 14028 by Fourier transform infrared spectroscopy. The detection of this microorganism was performed between 1060 and 960 cm−1 corresponding to carbohydrate and phosphate groups of the bacteria. The lowest detected concentration was 10 CFU/mL. This work confirms the utility of a-SiC:H to reliably and rapidly determine Salmonella. [ABSTRACT FROM AUTHOR]

Chia (Salvia hispanica L.) seeds contain antioxidants with great benefits for health and are widely used in the food industry. Antioxidants can be degraded by environmental factors, decreasing their biological activity. Their encapsulation in chitosan (CH) particles represents an alternative to protect them and increases their application. The encapsulation efficiency (%EE) of the antioxidants in the CH particles depends on the synthesis conditions. In this study, two methods for encapsulation of chia extract in chitosan particles were evaluated: method A, 0.05% CH in 1% acetic acid was mixed with 0.07% of tripolyphosphate (TPP) and method B, 0.3% CH in 2% acetic acid was mixed with 1% TPP. The results showed that the %EE decreased with the concentration of the extract, and the FTIR analysis suggested that the compounds of the extract were adsorbed on the surface of the particles. Dynamic light scattering and zeta potential analysis showed that the particles of method A are unstable and with a tendency to agglomerate, and the particles of method B are stable. The highest %EE was obtained with 0.2 mg·mL−1 (method A) and 1.0 mg·mL−1 (method B) of the extract. The higher loading capacity (%LC) (16–72%) was exhibited by the particles of method A. The best particle yield (62–69%) was observed for method B. The particles with the extract adsorbed showed antioxidant activity (5–60%) at 25°C; however, in the particles with the extract encapsulated, the activity increased after subjecting to acidic conditions at 40°C due to the breakdown of the particles. The results obtained will allow choosing the appropriate conditions for the synthesis of chitosan particles loaded with chia extracts with specific characteristics (%EE, %LC, size, and type) according to their future applications. The particles could be used in food and pharmaceutical industries and even in edible films for food packaging. [ABSTRACT FROM AUTHOR]

Green synthesis of gold nanoparticles using an aqueous coffee (Coffea arabica L.) pulp extract as a reducing agent was achieved and analyzed by response surface methodology, given the diverse applicability of these nanoparticles containing a wide range of phenolic compounds from the coffee pulp extract. Three factors (precursor concentration, reducing agent concentration, and reaction time) were considered and their combined effects on the maximum intensity MA, particle size d, and particle density N were analyzed. An opposing effect between the precursor and reducing agent was observed during synthesis, because although the precursor increased d and diminished N, the reducing agent diminished d and increased N. These effects were observed simultaneously through the response surfaces of d and N. This methodology allowed the synthesis of nanoparticles with an average particle size of 5–22 nm and N around 2.9 × 1011 − 3.7 × 1013 part/mL, depending on the response surface methodology, Box–Behnken design. The R2 value determined for all cases was 0.98 (MA), 0.99 (d), and 0.97 (N), clearly indicating that the model can be used to predict or design the response variables in the design space. Finally, Fourier transform infrared measurements showed that the organic compounds present in the aqueous coffee pulp extract were coating the surface of the gold nanoparticles. The proposed methodology could contribute to the design of new alternatives for the synthesis of specific nanostructures with potential applications in the therapeutic area. [ABSTRACT FROM AUTHOR]

Physicochemical and sensory properties of Adobera, a genuine, understudied Mexican raw‐milk cheese, were explored by analysing commercial samples from different manufacturers and seasons. Composition‐wise, Adobera could be considered a fresh cheese with a high moisture content (42.5%), although its relatively low water activity (0.953) and pH (5.14) and high free amino acid content (0.46 mmol/g, dry basis) could indicate otherwise. Instrumental texture corresponded to that of a semifirm cheese, while its colour was whitish‐to‐ivory. Both texture and composition were significantly affected by sampling season and cheese composition, while some attributes of sensory acceptability significantly varied with brand. [ABSTRACT FROM AUTHOR]

The water vapor permeability (WVP) and hardness of biodegradable nanocomposite films based on glutelin from Jatropha curcas L. were determined and the results were analyzed by response surface methodology (RSM). The effects of independent variables constituted by the plasticizer (glycerol), nanofiller (cloisite), and pH on the physical parameters were evaluated. The regression models obtained for each physical property adequately described the measurements used in the experimental design, with regression coefficients of 0.9513 and 0.9421 for WVP and hardness. The regression coefficients show that pH has the most significant effect on the WVP, whereas the cloisite content has the largest influence on the hardness of the nanocomposite film. Fourier transform infrared spectroscopy provided confirmation of the results obtained by RSM. Corroboration that the gluteline structure is in a similar form as the WVP and primarily influenced by pH was obtained using conventional and second derivative infrared spectra. However, the hardness of the film primarily depends on the cloisite content. This methodology may be useful for the design and elaboration of nanocomposite films based on J. curcas L. with specific barrier and mechanical properties. [ABSTRACT FROM AUTHOR]

Physalis ixocarpa Brot. ex Hornem. and Physalis angulata L. are two edible species of the family Solanaceae, which have an important variety of antioxidant compounds present in their roots, stems, leaves, calyces, and fruits. This work reports the development of multivariate models based on the use of partial least square (PLS) analysis and Fourier transform infrared (FTIR) spectroscopy for the quantitative determination of total phenolics, total flavonoids, free radical scavenging activity, total antioxidant capacity, and reducing power in the extracts of roots, stems, and leaves of both P. ixocarpa and P. angulata. Standard chromatographic and colorimetric techniques were used to determine the quantitative actual values (references) in the extracts, which served as input data to develop the multivariate PLS models. Optimized FTIR-PLS models were realized by cross-validation procedures, obtaining the determination coefficients for prediction between 0.792 and 0.905 for P. ixocarpa, and between 0.756 and 0.893 for P. angulata. In this form, FTIR spectroscopy with multivariate analysis could represent a versatile tool to evaluate quantitatively concentrations of bioactive compounds and antioxidant properties in the extracts of both species, requiring a very short time at low cost. [ABSTRACT FROM AUTHOR]

Computational identification of potential epitopes with an immunogenic capacity challenges immunological research. Several methods show considerable success, and together with experimental studies, the efficiency of the algorithms to identify potential peptides with biological activity has improved. Herein, an epitope was designed by combining bioinformatics, docking, and molecular dynamics simulations. The hemagglutinin protein of the H1N1 influenza pandemic strain served as a template, owing to the interest of obtaining a scheme of immunization. Afterward, we performed enzyme-linked immunosorbent assay (ELISA) using the epitope to analyze if any antibodies in human sera before and after the influenza outbreak in 2009 recognize this peptide. Also, a plaque reduction neutralization test induced by virus-neutralizing antibodies and the IgG determination showed the biological activity of this computationally designed peptide. The results of the ELISAs demonstrated that the serum of both prepandemic and pandemic recognized the epitope. Moreover, the plaque reduction neutralization test evidenced the capacity of the designed peptide to neutralize influenza virus in Madin-Darby canine cells. Copyright © 2015 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

The degradation of 2,6-dimethoxyphenol (DMP) and decolorization of Remazol brilliant blue R dye (RBB), added to culture media of Pleurotus ostreatus developed in submerged fermentation, and the laccase, manganese peroxidase and veratryl alcohol oxidase activities produced in these systems were evaluated. Both compounds were removed from the culture medium mainly by enzymatic action. These compounds decreased the specific growth rate and the effect on the maximal biomass values was not important. The enzymatic activities were increased by DMP and/or RBB; however, the DMP showed a higher inducer effect on all enzymes than RBB. On the other hand, the RBB showed a larger inducer effect on manganese peroxidase activity than on the laccases and veratryl alcohol oxidase activities. These results show that DMP was a better inducer of ligninolytic enzymes than dye, and the process of dye decolorization and degradation of DMP requires the action of all enzymes of the ligninolytic complex. [ABSTRACT FROM AUTHOR]