The evolution of knowledge in biological and medical areas which made possible scientific and technological advances are attributed to anatomical studies, physiology and immunology in animals, contributing to the discovery of prophylactic measures and treatments of diseases that affect humans and animals. Currently, substitution is suggested by alternative methods that do not use laboratory animals, however in vitro methods may never be able to provide similar results to in vivo methods. Mice and rats are the most used animals in experimental researches, the anatomical, histological and genetic differences between species should be carefully evaluated, to better apply the study model and avoid unnecessary waste avoid. This study, aimed at an anatomical comparative and histological relationship between a rat´s and a mouse´s organs, is of great importance in experimental studies. For such, 30 Mus musculus (Swiss) mice and 15 Rattus norvegicus (Wistar) male and heterogenic rats, were used. All animals were kept free of pathogenic microorganisms, with the absence of surgical interventions that could cause anatomical and physiological changes. It was possible to observe significant anatomical and histological differences between spleens, brains, hearts, stomachs and intestines, livers, eyes, lungs and kidneys among species, which will serve as a basis to assist in choosing the most satisfactory research model. Few studies relate specific characteristics among laboratory animals, being restricted to a few veterinary and zoology books. The greater the organic, physiological and anatomical similarities are with the human being, the greater is the applicability of the animals in studies. However, it is not possible to lay down general rules to validate the extrapolation from one species to another.

The companion paper (Rice 2020) found that the centromeric repeats of the Western European house mouse (Mus musculus domesticus) have unusual structure: i) despite moderate pairwise sequence divergence (average = 5.9%), no monomer sequence was common and many hundreds of monomer sequences were observed, ii) local sequence divergence among neighboring monomers was nearly as high as genome-wide divergence, and iii) matching sequences were rare between side-by-side monomers. Here I integrate information from many published studies to formulate a hypothesis for the evolution of this structure. Non-matching sequences of neighboring centromeric monomers is hypothesized to be selectively favored in the context of molecular drive because it reduces the rate of monomer deletion during repair of double strand breaks (DSBs) via the Single Strand Annealing (SSA) pathway. The foundation for the hypothesis is the observation that centromeres of most populations of M. m. domestics reside close to the telomere, i.e., all their chromosomes are telocentrics. This proximity influences repair of centromeric DSBs because it places at least part of the centromere within the Telomere-Affected Repair Region (TARR; a location with increased concentrations of the shelterin-complex proteins that bind telomeres, especially TRF2). Shelterin proteins increase the level of 5’→3’ end resection at DSBs and thereby: i) decrease the frequency of repair via the c- NHEJ pathway, and ii) increase the frequency of homology-directed repair (HD-repair) –including the SSA repair pathway. It is hypothesized that certain ‘trigger’ events (e.g., sub-telomeric deletions) occur in local populations that increase the influence of TARR on the centromere. This increase elevates the occurrence of SSA repair of centromeric DSBs to a level that causes centromeres to begin to gradually shrink. Chronic shrinkage leads to coevolution between centromere size and karyotype number. Once centromeres shrink to a size below a critical minimum (that causes substantially reduced kinetochore size), fusions between non- homologous telocentrics with undersized centromeres produces metacentrics with an expanded centromere size (and a corresponding ‘quantum-jump’ in kinetochore size). These metacentrics: i) accumulate to fixation because they are favored by centromere drive, and ii) are released from the influence of TARR and thereby gradually recover larger centromere size. Fission of metacentrics with enlarged centromeres can next plausibly regenerate pairs of telocentrics with sufficiently large centromeres (which recruit normal-sized kinetochores) to be favored by centromere drive and accumulate to fixation. This fixation completes a cycle of coevolution within genomes that oscillate between two extremes: i) high karyotype number (2N = 40; all telocentrics) with larger centromeres, and ii) low karyotype number (2N << 40; mainly metacentrics) with initially small centromeres that gradually increase in size.

The banana, also known as plantain in some places, is a tropical fruit widely consumed and appreciated around the world. Its scientific name is Musa paradisiaca and it belongs to the Musaceae family. This fruit is native to Southeast Asia but is currently cultivated in various tropical and subtropical regions, is harvested throughout all the year and planted in 130 countries, 75% of which is produced mainly in India, Ecuador, Brazil, Colombia, Costa Rica and China. The use of some post-harvest treatments (gradening, modification of the atmosphere, coatings and refrigeration, among others) are important for guarantee of safe, healthy and high-quality foods in the century XXI. This review details mechanical damage after harvest, management of environmental parameters (temperature and relative humidity), control of gases involved in storage and transportation, treatment with wax, coatings, the use of antifungal compounds and packaging necessary for the export of the fruit.

Mouse wild-derived strains (WDS) combine the advantages of classical laboratory stocks and wild animals, and thus appear as promising tools for diverse biomedical and evolutionary studies. We employed 18 WDS representing three non-synanthropic species (Mus spretus, M. spicilegus, and M. macedonicus) and three house mouse subspecies (M. musculus musculus, M. m. domesticus, M. m. castaneus) which are all important human commensals to explore whether the number of major urinary protein (MUP) genes and their final protein levels in the urine are correlated with the level of commensalism. Contrary to expectations, MUP copy number (CN) and protein excretion in the strains derived from M. m. castaneus, which is supposed to be the strongest commensal, were not significantly different from the non-commensal species. Regardless of an overall tendency for higher MUP amounts in taxa with higher CN, there is no significant correlation at the strain level. Our study thus suggests that the expansion of the Mup cluster, which appeared before the house mouse diversification, is unlikely to facilitate commensalism with humans in the three house mouse subspecies. Finally, we found considerable variation among con(sub)specific WDS, warning against generalisations of results based on a few strains.