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In this study, the microbial interactions among cocultures of Streptococcus thermophilus (St) with potential probiotics of Bifidobacterium animalis ssp. lactis (Ba) and Lactiplantibacillus plantarum (Lp) in fermented milk were investigated during a storage period of 21 d at 4°C, in terms of acidifying activity (pH and titratable acidity), viable counts, and metabolites. A nontargeted metabolomics approach based on ultra-high-performance liquid chromatography coupled with mass spectrometry was employed for mapping the global metabolite profiles of fermented milk. Probiotic strains cocultured with St accelerated milk acidification, and improved the microbial viability compared with the single culture of St. The St-Ba/Lp treatment manifested a higher bacteria viability and acidification ability in comparison with the St-Ba or the St-Lp treatment. Relative quantitation of 179 significant metabolites was identified, including nucleosides, AA, short peptides, organic acids, lipid derivatives, carbohydrates, carbonyl compounds, and compounds related to energy metabolism. The principal component analysis indicated that St treatment and coculture treatments displayed a complete distinction in metabolite profiles, and Lp had a larger effect than Ba on metabolic profiles of fermented milk produced by cofermentation with St during storage. The heat map in combination with hierarchical cluster analysis showed that the abundance of metabolites significantly varied with the starter cultures over the storage, and high abundance of metabolites was observed in either St or coculture samples. The St-Ba/Lp treatment showed relatively high abundance for the vast majority of metabolites. These findings suggest that the profile of the metabolites characterizing fermented milk samples may depend on the starter cultures, and incorporation of probiotics may considerably influence the metabolomic activities of fermented milks., (Copyright © 2021 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.)

MicroRNAs (miRNAs) are small (about 22 nucleotides) noncoding RNAs, which were highly conserved among mammals. They have ushered in a new era in molecular biology over twenty years. They can negatively regulate gene expression at the posttranscriptional level through the principle of complementary base pairing with the 3' untranslated region (UTR) of their target mRNAs and induce their degradation. They involve in tissue morphogenesis, cellular processes like apoptosis, and major signaling pathways. Previous studies have promoted our understanding that miRNAs play an important role in myogenesis and have a big impact on muscle mass, muscle fiber type and muscle diseases. Many researchers have provided evidence of the involvement of muscle-specific and enriched miRNAs in the individual stages of skeletal muscle development as well as of their significant influence on muscle metabolism during quiescence, proliferation, differentiation and regeneration. Here, we focus on the microRNAs that related to the development of skeletal muscle. For example, some microRNAs are upregulated in differentiated skeletal muscle and can promote differentiation, like, miR-1, miR-24, miR-26a, miR-181 and miR-206. However, some microRNAs highly expressed in proliferating myoblasts, downregulated in differentiated and could inhibit differentiation, like MiR-221 and miR-222. Some others not only promote skeletal muscle proliferation, but also promote differentiation, like miR-214. Studying the miRNAs' regulatory mechanisms in skeletal development will help us know more about the knowledge of miRNAs in muscle developmental biology and make us learn more about involved signal pathway., (Copyright © 2018 Elsevier B.V. All rights reserved.)

This paper reports an interesting case of myelodysplastic syndrome (MDS), whose bone marrow karyotype at diagnosis was 46, XY, t(16;17) (q12;q25). Fourteen months later, the disease transformed into erythroleukemia, and several correlative clones with hyperdiploid appeared at the same time. Thus, we consider that detecting karyotypic evolution may help evaluate the prognosis of MDS.