Peroxisomes and mitochondria are organelles that perform major functions in the cell and whose activity is very closely associated. In fungi, the function of these organelles is critical for many developmental processes. Recent studies have disclosed that, additionally, fungal development comprises a dynamic regulation of the activity of these organelles, which involves a developmental regulation of organelle assembly, as well as a dynamic modulation of the abundance, distribution, and morphology of these organelles. Furthermore, for many of these processes, the dynamics of peroxisomes and mitochondria are governed by common factors. Notably, intense research has revealed that the process that drives the division of mitochondria and peroxisomes contributes to several developmental processes—including the formation of asexual spores, the differentiation of infective structures by pathogenic fungi, and sexual development—and that these processes rely on selective removal of these organelles via autophagy. Furthermore, evidence has been obtained suggesting a coordinated regulation of organelle assembly and dynamics during development and supporting the existence of regulatory systems controlling fungal development in response to mitochondrial activity. Gathered information underscores an important role for mitochondrial and peroxisome dynamics in fungal development and suggests that this process involves the concerted activity of these organelles.

Introduction. Periodontal disease (PD) is a chronic inflammation of the soft tissues that support the structure of the tooth, and miRNAs are highly dynamic molecules that participate in the regulation of gene expression interfering with multiple genetic targets. The dysregulation of the expression of miRNAs has been associated with different types of pathologies; therefore, they are excellent molecules to be studied as biomarkers. Material and Methods. A search was made in the electronic databases of PubMed, Scopus, and Science Direct. The following key words were used: “microRNAs,” “miRNAs,” “periodontal disease,” “periodontitis,” and “biomarker”; employee independent search strategies with the Boolean operators “OR” and “AND”; a further search of the references of the selected studies was performed to detect potential studies that met the selection criteria. The data recollected from each article were author, country, year of publication, sample size, type of sample used to identify miRNAs, methodology used to identify miRNAs, type of periodontal disease, and miRNAs identified. Results. Of the 13 selected studies, 6 used gingival tissue as a sample for the identification of miRNAs, 3 used gingival fluid, 2 used saliva, 1 used serum, and another used periodontal tissue. Chronic periodontitis was the most studied periodontal disease in 9 of the 13 selected articles; 7 used microarrays as the main technique for the identification of miRNAs. qRT‐PCR was the assay choice to validate the identified miRNAs. Conclusion. The main type of periodontal disease on which most studies are focused is chronic periodontitis, with the main miRNAs being hsa‐miR‐146a, hsa‐miR‐146b, hsa‐miR‐155, and hsa‐miR‐200. This systematic review is one of the first to carry out an analysis of the current role of miRNAs in PD as biomarkers.

Recently, the 3D spheroid cell culture application has been extensively used in the treatment of bone defects. A wide variety of methodologies have been used, which has made the comparison of results complex. Therefore, this systematic review has two aims: (i) to perform an analysis focused on the role of 3D spheroid cell culture in bone regeneration strategies; and (ii) address the main challenges in clinical application. A search of the following keywords "3D cell culture", "spheroid", and "bone regeneration" was carried out in the PubMed, Scopus, and ScienceDirect databases and limited to the years 2010-2020. Studies were included if their primary objective was the behavior of cell aggregates to formed spheroids structures by different 3D cell culture techniques focused on the regeneration of bone tissue. To address the risk of bias for in vitro studies, the United States national toxicology program tool was applied, and descriptive statistics of the data were performed, with the SPSS V.22 program. A total of 16 studies were included, which met the established criteria corresponding to in vitro and in vitro/in vivo studies; most of these studies used stem cells for the 3D cell spheroids. The most often methods used for the 3D formation were low adherence surface and rotational methods, moreover, mesenchymal stem cells were the cell line most frequently used because of their regenerative potential in the field of bone tissue engineering. Although the advances in research on the potential use of 3D spheroids in bone regeneration have made great strides, the constant innovation in cell spheroid formation methodologies means that clinical application remains in the future as strategy for 3D tissue bioprinting.

En febrero del presente año la Organización Mundial de la Salud (OMS) dio a conocer la presencia de una nueva cepa de un virus que estaba generando enfermedades respiratorias altamente contagiosas, el COVID- 19, ¿pero qué es este virus? Los coronavirus (CoVs) son una familia de virus con genoma RNA pertenecientes al orden Nidovirales, los cuales se han clasificado en tres subgrupos α, β, y γ, los subtipos “α” y “β” se encuentran distribuidos en mamíferos, incluyendo humanos y el subtipo “γ” en aves, sin embargo, un cuarto grupo denotado como “δ” ha sido reclasificado debido a su capacidad de infectar porcinos ¹; estos subtipos de coronavirus se caracterizan principalmente por generar enfermedades de tipo respiratorio y gastrointestinales ².

Introduction: Biodentine (BD), a dentin substitute, is currently used to treat external cervical root resorption, but its effects on gingival fibroblasts (GFs) are not fully known. Objective: To investigate and compare BD and MTA (mineral trioxide aggre-gate) in terms of proliferative, migratory, and adhesion effects on human pulpal and gingival cells. Material and Methods: Cells were incubated directly on the surface of BD and MTA disks. Adhesion (4 and 24 h) and proliferation (3, 5, 7, 14, 21) were evaluated with crystal violet and MTT assays (n=9 X each group). A wound-healing assay was performed for cell migration, with 0.2 and 2 µg/ml MTA or BD (n=6 X each group). The cut-off point for statistical significance was set at p<0.05, p<0.01 and p<0.001. Results: The best adhesion and proliferation results for gingival fibroblast (GFs) were obtained with BD (p<0.01). MTA and BD enhanced the migration of GFs in a dose-dependent manner, with superior results with BD, and 2 µg/ml was the optimal concentration for enhancing the migration of GFs. Conclusion: Results indicate that BD and MTA exhibit excellent compatibility in terms of cell adhesion, proliferation, and cellular migration. Also, the results suggested that BD is associated with better results than MTA in GFs. The results support the clinical application of BD in areas colonized with GFs.