Introduction. Type 2 diabetes mellitus (T2DM) is a chronic and multifactorial metabolic disease characterized by sustained hyperglycemia, insulin resistance, and progressive β-cell dysfunction. In Latin America and particularly in Ecuador T2DM represents a growing public health concern. Among genetic determinants, single nucleotide polymorphisms (SNPs) have emerged as key markers influencing insulin secretion, lipid metabolism, and insulin sensitivity. Objective. To analyze the main SNPs associated with genetic susceptibility to developing T2DM, considering both risk and protective variants reported between 2019 and 2024. Methodology. A systematic bibliographic review was conducted following PRISMA guidelines. Searching was performed in PubMed, Scielo, Web of Science and the Virtual Health Library (VHL), using MeSH/DeCS terms combined with Boolean operators. Included studies were quantitative originals and meta-analyses published between 2019 and 2024 that evaluated associations between SNPs and T2DM and reported statistical measures (OR, CI, p-value). Narrative reviews without primary data, studies in animals, duplicates, and articles outside the time frame were excluded. A total of 17 studies met the inclusion criteria. Results. SNPs associated with impaired insulin secretion included KCNJ11 rs5210, CYP2D6 rs1065852, ABCC8 rs1799854, and TCF7L2 rs7903146, all reporting significant associations (OR 1.34–2.07), consistent with alterations in K-ATP channel function or incretin-mediated pathways. Variants linked to insulin resistance included ADIPOQ rs17846866/rs1501299, FTO rs9939609/rs17817449, IGF2BP2 rs6769511, and HHEX rs1111875, associated with adipogenesis, metabolic inflammation, and hepatic regulation (OR 1.37–3.02). Conversely, PPARG rs3856806 demonstrated a protective effect (OR=0.82), suggesting beneficial modulation of insulin sensitivity and lipid metabolism. Conclusion. The analyzed SNPs are relevant biomarkers for understanding genetic susceptibility to T2DM; however, their clinical applicability remains limited due to complex gene–environment interactions. Strengthening longitudinal research in Latin American populations is recommended to develop population-specific polygenic risk models and advance precision medicine approaches. General Area of Study: Clinical Laboratory. Specific area of study: Molecular biology. Type of study: Systematic bibliographic review.

Introduction: inflammatory bowel diseases (IBD) - primarily Crohn’s disease (CD) and ulcerative colitis (UC) - are chronic disorders of the gastrointestinal tract characterized by persistent inflammation and immune dysregulation, involving genetic, epigenetic, microbiota-related, and environmental factors. Their diagnosis still relies on invasive methods such as colonoscopy, histology, and serum or fecal biomarkers, which show limitations in specificity and discriminative capacity. This scenario has driven the search for non-invasive tools such as microRNAs, small regulatory RNA fragments with high stability that could accurately differentiate between UC and CD. Objective: to evaluate recent evidence on the differential expression of various microRNAs in IBD and their utility as non-invasive diagnostic biomarkers, comparing them with conventional markers such as fecal calprotectin. Methodology: a narrative review was conducted based on a structured search in BVS, PubMed, Web of Science, and Scopus, using DeCS/MeSH terms related to “MicroRNAs,” “Inflammatory bowel disease,” “Crohn disease,” and “Ulcerative colitis.” Articles published in the last five years, in English or Spanish, evaluating the differential expression of microRNAs in IBD were included. Development: several microRNAs show characteristic expression patterns depending on the pathology. In UC, overexpression of miR-16-5p, miR-21-5p, miR-23a-5p, miR-24-3p, miR-29a-3p, miR-126-3p, miR-195-5p, and let-7f-5p has been reported, whereas miR-192-5p, miR-375-3p, and miR-422b-5p are downregulated (9,10,20). In CD, miR-21-5p, miR-16-5p, miR-155-5p, and miR-223-3p are overexpressed, with reduced levels of miR-192-5p and miR-375-3p. These microRNAs participate in key processes such as inflammation, apoptosis, autophagy, and epithelial barrier regulation, supporting their clinical potential. Moreover, some—such as miR-223 and miR-146b-5p—may surpass traditional biomarkers like fecal calprotectin in sensitivity and specificity. Conclusion: microRNAs represent strong candidates as non-invasive diagnostic biomarkers in IBD due to their biological stability, differential expression between UC and CD, and direct relationship with pathophysiological mechanisms. Although the evidence is promising, standardized clinical studies are still needed to validate their routine use in medical practice. General Area of Study: Clinical laboratory. Specific area of study: Molecular biology. Type of study: Narrative review.

Introduction: Energy supplementation in dairy cows is an essential strategy to mitigate the negative energy balance during the transition and boost productivity in different production systems. Objectives: The purpose of this review is to synthesize the scientific evidence on energy supplementation in dairy cows, evaluating its impact on productive and metabolic parameters DMI, energy-corrected milk (ECM), NEFA, BHBA and glucose. Methodology: This review followed a descriptive and systematic approach, based on the PRISMA guidelines adapted to animal production research. Results: This review integrated recent scientific evidence on various supplements such as protected fats, processed cereals, phytonutrients, agro-industrial by-products, and metabolic additives. Traditional supplements, especially protected fats (palmitate, calcium salts of fatty acids) and processed cereals (wet grain corn, cracked wheat), improve milk production. In contrast, phytonutrients, such as capsaicin and essential oils, show more variable results, although with favorable trends in dry matter intake, feed efficiency, and some metabolic indicators. Agro-industrial by-products, such as cocoa bark and orange waste, are economical and sustainable alternatives, capable of maintaining production if used at appropriate levels of inclusion. On the other hand, metabolic additives and micronutrients such as propylene glycol, propionate, choline and protected methionine have been shown to improve energy balance, reduce fatty acids and β-hydroxybutyrate, decreasing the risk of metabolic disorders in the postpartum period. Conclusions: results of this review show that traditional energy supplements such as protected fats and processed cereals are the most consistent in improving milk production and energy-corrected milk. General area of study: medicine. Specific area of study: veterinary. Type of article: systematic bibliographic review.

Introduction: Post-treatment Apical Periodontitis (PAPT) is a frequent cause of endodontic failure, strongly associated with the persistence of intraradicular infection. In cases where conventional retreatment or periapical surgery are contraindicated due to anatomical limitations, Intentional Reimplantation (IR) emerges as a conservative therapeutic alternative. The complementary use of Injectable Platelet-Rich Fibrin (i-PRF) provides an additional benefit, by promoting tissue regeneration through the sustained release of growth factors. Objectives: This report describes the management of an upper second molar (2.7) with PAPT and critical proximity to the maxillary sinus. Methodology: A descriptive report corresponding to a clinical case report aimed at documenting the clinical management and postoperative evolution of a tooth with post-treatment apical periodontitis by intentional reimplantation supplemented with injected platelet-rich fibrin (I-PRF). Results: An IR was performed with extraoral apicoectomy, retrograde obturation with bioceramics and application of i-PRF in the alveolus. The extraoral time was 10 minutes and 20 seconds, respecting the established operating protocols. At six months, clinical and tomographic controls showed significant bone healing, recovery of the periodontal ligament space, and adequate functional integration of the specimen, without recurrence of the lesion. Conclusions: The present case highlights the viability of IR complemented with i-PRF as an effective option to preserve teeth with PAPT in complex situations, where conventional surgery is not feasible, integrating microsurgical techniques and regenerative biomaterials in current endodontic practice. General area of study: Dentistry. Specific area of study: Endodontics. Type of article: Clinical case.