Shifting to machine supervision: annotation-efficient semi and self-supervised learning for automatic medical image segmentation and classification.

Advancements in clinical treatment are increasingly constrained by the limitations of supervised learning techniques, which depend heavily on large volumes of annotated data. The annotation process is not only costly but also demands substantial time from clinical specialists. Addressing this issue, we introduce the S4MI (Self-Supervision and Semi-Supervision for Medical Imaging) pipeline, a novel approach that leverages advancements in self-supervised and semi-supervised learning. These techniques engage in auxiliary tasks that do not require labeling, thus simplifying the scaling of machine supervision compared to fully-supervised methods. Our study benchmarks these techniques on three distinct medical imaging datasets to evaluate their effectiveness in classification and segmentation tasks. Notably, we observed that self-supervised learning significantly surpassed the performance of supervised methods in the classification of all evaluated datasets. Remarkably, the semi-supervised approach demonstrated superior outcomes in segmentation, outperforming fully-supervised methods while using 50% fewer labels across all datasets. In line with our commitment to contributing to the scientific community, we have made the S4MI code openly accessible, allowing for broader application and further development of these methods. The code can be accessed at https://github.com/pranavsinghps1/S4MI .

Lactobacillus fermentum WC2020 increased the longevity of Caenorhabditis elegans via JNK-mediated antioxidant pathway.

Lactobacillus fermentum can exert antiaging effects, but their roles are strain-specific, and little is known about the molecular mechanisms in some strains. This study investigated the antiaging effects of L. fermentum WC2020 (WC2020) isolated from Chinese fermented pickles and the underlying mechanism of the action in Caenorhabditis elegans. WC2020 enhanced the mean lifespan of L1-stage and L4-stage worms by 22.67% and 12.42%, respectively, compared with Escherichia coli OP50 (OP50), a standard food source for C. elegans. WC2020-induced longevity was accompanied by an increase in body length and mitochondrial transmembrane potential and a reduction in lipid accumulation and the production of reactive oxygen species and malondialdehyde. Moreover, WC2020 increased the production of glutathione, superoxide dismutases, and catalases and altered the transcripts of many phenotype-related genes. Furthermore, WC2020-fed jnk-1 rather than akt-2 or pmk-1 loss-of-function mutants showed similar lifespans to OP50-fed worms. Correspondingly, WC2020 significantly upregulated the expression of jnk-1 rather than genes involved in insulin-like, p38 MAPK, bate-catenin, or TGF-beta pathway. Moreover, the increase in body length, mitochondrial transmembrane potential, and antioxidant capability and the decrease in lipid accumulation induced by WC2020 were not observed in jnk-1 mutants. Additionally, WC2020 increased the expression of daf-16 and the proportion of daf-16::GFP in the nucleus, and increased lifespan disappeared in WC2020-fed daf-16 loss-of-function mutants. In conclusion, WC2020 activated the JNK/DAF-16 pathway to improve mitochondria function, reduce oxidative stress, and then extend the longevity of nematodes, suggesting WC2020 could be a potential probiotic targeting JNK-mediated antioxidant pathway for antiaging in food supplements and bioprocessing. PRACTICAL APPLICATION: Aging has a profound impact on the global economy and human health and could be delayed by specific diets and nutrient resources. This study demonstrated that Lactobacillus fermentum WC2020 could be a potential probiotic strain used in food to promote longevity and health via the JNK-mediated antioxidant pathway.

Mechanism of recombinant bacteria adsorb UO22+ under culture condition.

Research on the ability and mechanism of genetically recombinant E. coli DH5α containing DSR A gene to enrich uranium under culture conditions provides a theoretical basis for the application of the bacteria in the treatment of uranium pollution. By exploring the influence of factors such as the initial concentration of uranium, culture time, and inoculation amount on the characteristics of uranium enrichment in genetically recombinant E. coli, using FTIR, SEM-EDS, XPS and XRD explore the mechanism of uranium-enriched bacteria. The results showed that when initial UO22+ concentration reach 600 mg/L, E. Coli D1 could not survived, indicated that the maximum tolerance concentration is lower than 600 mg/L. While concentration between 0∼500 mg/L, strains D1 can grow normally and has the ability to enrich uranium. In the prime stage, strains D1 resist toxics through release inorganic phosphates to precipitate UO22+ on cell wall, after 96 h, most UO22+ were transferred into cytoplasm and metabolized into U(IV) which is less toxic. In the metabolize process, all groups involved in metabolizing UO22+, especially protein contain groups like hydroxyl, amine and carboxyl paly a huge role. It shows that within a certain concentration rage, strains D1 has a good enrichment effect on uranium under culture conditions.