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Exosomes are lipid membrane-enclosed vesicles released by all cell types that act at the paracrine or endocrine level to favor cell differentiation, tissue homeostasis, organ remodeling and immune regulation. Their biosynthesis begins with a cell membrane invagination which generates an early endosome that matures to a late endosome. By inward budding of the late endosome membrane, a multivesicular body (MVB) with intraluminal vesicles (ILVs) is generated. The fusion of MVBs with the plasma membrane releases ILVs into the extracellular space as exosomes, ranging in size from 30 to 100 nm in diameter. The bilipid exosome membrane is rich in cholesterol, ceramides and phosphatidylserine and can be loaded with DNA, RNA, microRNAs, proteins and lipids. It has been demonstrated that exosome secretion is a common mechanism used by the tumor to generate an immunosuppressive microenvironment that favors cancer development and progression, allowing tumor escape from immune control. Due to their ability to transport proteins, lipids and nucleic acids from the cell that gave rise to them, exosomes can be used as a source of biomarkers with great potential for clinical applications in diagnostic, prognostic or therapeutic areas. This article will review the latest research findings on exosomes and their contribution to cancer development.

Six microsatellite loci, isolated for Piaractus mesopotamicus (Characidae, Serrasalminae) were used to evaluate the genetic variability of the dorada (Brycon moorei sinuensis, Characidae, Bryconinae) population in the Sinú River, Córdoba, Colombia, and to facilitate management recommendations for this species. The six loci were polymorphic, with an average of 9.25 alleles for dimeric loci (Pme2, Pme4, Pme5 and Pme20), and five alleles for trimeric loci. Tests for linkage disequilibrium were used to determine that the six loci had an independent distribution. The observed heterozygosities were lower than the expected ones for all loci, and the population was not in Hardy-Weinberg equilibrium because of heterozygote deficiency. F-statistics indicated inbreeding and a low population substructure. The homogeneity of the population was confirmed by high values of genetic flux and an agglomerated representation of the individuals, based on factor correspondence analysis. Recent bottlenecks were detected for three sample sites under the assumption of an infinite allele mutation model. Proposals for the management of the dorada population are made and validated with a genetic simulation.

In seeking environmentally clean technologies, this research has assessed a new alternative to synthesize activated carbon of Colombian mineral coal by using gases from partial combustion of propane (hereafter called flue gases), which are generally exhausted to the atmosphere. The activation was carried out by two methods of synthesis: in the first, pyrolysis was performed prior to activation, while in the second, pyrolysis and activation were carried out simultaneously. This alternative of synthesizing activated carbon was compared with conventional activation of coal using CO 2 . The activated carbon with flue gases and CO 2 were characterized by adsorption of argon at −186 °C, and parameters such as specific surface area, pore size distribution, total pore volume, and micropore volume were determined. The activation with flue gases reduced combustion gas components such as SO 2 , NOx, and CO 2 during the coal activation process. Activation with flue gases resulted in a surface area of 804 m 2 /g and a total pore volume of 0.38 cm 3 /g, while activation with CO 2 produced a surface area of 1252 m 2 /g and a total pore volume of 0.43 cm 3 /g. Subsequently, the application to methane storage was evaluated and found to exceed the reported performance for several commercial carbons with storage factors up to 112.