M S-medecine Sciences最新文献

The gut microbiome plays an important role in animal physiology and development. While the molecular, cellular and ecological mechanisms that determine its diversity and impact on animal health are beginning to unfold, we still know relatively little about its evolutionary history. Fundamental questions such as "Is the microbiota evolving and at what race?", "What are its origins?", "What are the consequences of microbiota evolution for human health?" or "Did we co-evolve with our gut bacteria?" are only beginning to be explored. In the short term (from a few days to a few years, or microevolution), gut microbes can evolve and adapt very rapidly within an individual in responses to environmental changes, such as diet shifts, which can affect human health. On the longer term (ten to millions of years, or macroevolution), evolution within individuals is counterbalanced by the transfer of microbes from other people, so that human evolution is decoupled from the evolution of most gut microbes over many generations. This suggests that, while gut microbes have probably evolved rapidly within humans, most of them have a history of exchange between host populations over millennia. Whether the evolution of the microbiota over the last hundreds of thousands of years has facilitated human adaptations remains an open question and an exciting avenue for future research.

The overall results of a research project represent a synthesis of the individual results obtained from the participants, which together lead to the conclusions of the research. The importance of informing participants is emphasised in the recommendations on research ethics. However, this good practice is not systematic and can present various challenges in its implementation, despite the fact that participants often express a desire to be informed. The potential advantages and disadvantages of this method raise questions for researchers, who have the task of conveying a coherent message to all parties, while at the same time addressing the lack of guidance on this practice. Potential avenues for improvement include expending the body of ethics literature on the subject and developing comprehensive guidelines to provide optimal support for research teams using this practice.

The direct application of cold plasmas at atmospheric pressure, corresponding to partially ionized gases, is an emerging technology with a number of potential biomedical applications, including the decontamination of surgical devices. A new derived and easier to implement method has recently been developed: the use of cold atmospheric plasma-activated media (PAM). Numerous preclinical studies and in vitro models indicates that PAM treatments facilitate wound healing by promoting keratinocytes and fibroblasts migration, stimulating angiogenesis, and inhibiting bacterial proliferation, all of which are essential for this vital process. PAM treatments induce the expression of cytokines, growth factors and matrix metalloproteinases, reduce cellular adhesion, and promote cytoskeletal changes, probably under the influence of plasma-generated reactive oxygen and nitrogen species. PAM treatments represent a promising novel therapy for treating chronic skin and mucosal wounds.

The existence of multigene families is the result of gene duplication. In vertebrates, the genes coding for the chemoreceptors involved in olfaction often form large families, sometimes comprising several thousand genes. In this case, it is assumed that a large number of genes is essential to discriminate between a large number of odorant molecules, and that the ability to identify a large number of odors may be necessary for different purposes, such as finding food and sexual partners, and avoiding predators. However, it has been found that in some species the number of these genes is very small, resulting from the secondary loss of many genes. This massive loss of genes is not always clearly associated with a change in the biology of the species or its environment, but in some cases, it is associated with drastic changes, such as the return to aquatic life in tetrapods.