Dalia Isabel Sánchez Machado

Balamuthia mandrillaris is a free-living amoeba pathogenic to humans, causing amoebic granulomatous encephalitis (GAE). Due to the associated mortality rates of Lippia graveolens could be an interesting alternative since it has been used against bacteria, fungi, and other pathogenic protozoa. This study employed RNA sequencing to analyze differentially expressed genes (DEGs), following treatment with two fractionated L. graveolens extracts (concentration: 150 µg/mL) at 48, 96, and 120 h. The DEGs identified are associated with several functions such as stress responses (Prohibitin domain-containing protein), and oxidative damage repair and cell stability (Peroxiredoxin). Genes implicated in virulence and host interaction also showed significant expression changes, such as the ADP ribosylation factor (Arf) GTPase and ephrin type-A receptor, alongside transcription factors involved in the phagocytosis of amoebas. Additionally, the analysis of Gene Ontology categories revealed terms including transmembrane signaling receptor and protein tyrosine activity, DNA replication initiation, the mitotic M phase, and membrane integrity. These results provide valuable insights into the molecular mechanisms utilized by B. mandrillaris to respond to environmental stressors and the repression of genes related to essential functions, which could serve as potential targets for developing novel strategies.

Biomaterials developed with biopolymers contribute to the healing process of healthy or diabetic patients. The objective of the present study was to evaluate the effect of honey incorporation (0.3, 0.6, and 1.2 g/100 mL) in chitosan/collagen/glycerol composite films. The Ch/Coll/1.2H films revealed the greatest percentage of elongation (27.10%) and Young´s modulus (65.58 MPa). The barrier properties (WVTR and WVP) exhibited a significant increase when the honey was incorporated into the films. The absorption capacity, solubility, and enzymatic biodegradability were lower in films containing honey. The chemical interactions between the functional groups of the films were verified by FTIR. The morphology studied by SEM confirmed the mixture’s homogeneity. Finally, all formulations exhibited antibacterial properties against Staphylococcus aureus, Pseudomonas aeruginosa, Listeria monocytogenes, and Salmonella Typhimurium. The aforementioned properties of formulated dressings are suitable for their potential application in chronic wounds.

Review question / Objective: Review question: Does chitosan base nanofibers has significant wound healing therapeutics effects in animal models? A preclinical systematic review of intervention will be carried out to evaluate the therapeutic effects of chitosan nanofibers on animal skin lesions. The PICO (Population, Intervention, Comparator, Outcome) scheme will be used: Intervention: full-thickness skin lesions, and the application of chitosan nanofibers as treatment for animal skin lesions. Regardless of the concentration of chitosan or other added compounds used. Comparison: No intervention, topical placebo agents and standard skin lesions treatments will be included. Outcome: wound healing area, wound closure, type of wound closure (first, second or third intention), healing time, infectious processes (antibacterial/antifungal properties), blood loss (hemostatic properties) and adverse effects.

Escherichia coli is one of the most important bacteria associated with the consumption of meat products causing human disease, with bovines as the main reservoir for this organism. Microbiological quality of raw meat sampled at slaughterhouses was evaluated by measuring the presence of Escherichia coli serogroups that produce the Shiga toxin (referred to as STEC), including both O157:H7 and non-O157 strains can cause Hemolytic Uremic Syndrome (HUS). The purpose of this study was to detect STEC O157 and non-O157 in meat products from Federal Inspection Type (FIT, n=52) and non-FIT (n=88) slaughterhouses, as well as butcheries (n=50), in southern Sonora, Mexico. To achieve this aim, selective media were employed to obtain putative O157:H7 colonies (TS-SMAC agar and Rainbow® agar O157), followed by multiplex PCR for the stx1, stx2, eaeA, and rfB genes, using the O157:H7 serotype as a control. No STEC O157 was found in beef products, but some non-O157 isolates were found containing the stx2 pathogenicity gene (1.40%, 3/224) and/or the fliCH4 flagellar antigen (1.78%, 4/224). This work also confirmed the susceptibility of strains with the stx2 and/or fliCH4 genes to several antibiotics and multi-resistance of all or some of these strains to trimethoprim/sulfamethoxazole, tetracycline, clarithromycin, penicillin G, oxacillin, ampicillin and cefazolin. This study comprises the first report of STEC non-O157 in Sonora and will be useful to establish their association with foodborne outbreaks originating from beef and pork consumption in the future.

Background and Objectives: Nutritional benefits of amaranth addition to maize products have been documented. However, studies of the effect on the final product's rheological and textural properties are scarce. The objective was to study the effect of amaranth addition on masa's rheological properties and the tortilla texture of maize nixtamalized flours obtained by extrusion technology.Findings: Composite flours of maize with 0%, 15%, 30%, or 45% amaranth were extruded, and masa and tortillas were obtained. Masa properties were evaluated with dynamic rheology and tortilla firmness with the texture profile analysis. The amaranth addition effect was not linear. Fifteen percent addition increased frequency sweep values for G′ and G″, while 30% and 45% addition decreased them. Tortilla firmness decreased at 2 storage hours for 15% addition compared with maize‐only samples (5440 and 7190 (g‐f)/mm). The effects can be partially explained by differences in starch characteristics.Conclusions: Amaranth (15% addition) improved masa viscoelastic behavior and reduced firmness during storage. Besides the nutritional effects, amaranth use at the tested level will be helpful in improving the texture of maize tortillas produced with extruded flour.Significance and Novelty: The texture of tortillas obtained by extruded flours has not been reported to be completely satisfactory; therefore, the use of amaranth has the potential to improve the final product quality.

Background:: The pseudo-cereal quinoa has attracted worldwide attention in recent years, due to it being considered a functional food. This stress-tolerant crop has historically been used by Andean cultures as a staple food. Nowadays, the consumption of quinoa in high-income countries is increasing due to it being associated with numerous health benefits, namely related with cardiovascular health. Objective:: We have carried out an extensive review on quinoa, including its main uses, applications, and components (nutrients, antinutrients, and bioactives) and their relationship with biological activities and cardiovascular health. Key findings and conclusions:: Quinoa possess numerous activities, including protection against cardiovascular, metabolic, and degenerative diseases, improvement of the immune system, reduction of symptoms associated with post-menopause, and promotion of muscle mass increase. Some of quinoa’s activities are due to its balanced amino acid profile, high fiber content, presence of phosphorus, iron, potassium, magnesium, vitamin E, and B vitamins. A plethora of bioactives can also be found in quinoa, such as phytosterols, saponins, phenolics, bioactive peptides, and phytoecdysteroids. More research is needed to better understand the mechanisms of action involved in the biological/therapeutic action of some quinoa components, namely those related with the potential to reduce cardiovascular disease (CVD) risk markers. The knowledge of factors that affect quinoa variability, such as processing conditions, is also of great importance for being able to obtain more benefits from this crop.