Tracking the extracellular and intracellular antibiotic resistance genes across whole year in wastewater of intensive dairy farm

Monitoring the annual variation of antibiotic resistance genes (ARGs) in livestock wastewater is important for determining the high-risk period of transfer and spread of animal-derived antibiotic resistance into the environment. However, the knowledge regarding the variation patterns of ARGs, especially intracellular ARGs (iARGs) and extracellular ARGs (eARGs), over time in livestock wastewater is still unclear. Herein, we conducted a year-round study to trace the profiles of ARGs at a Chinese-intensive dairy farm, focusing on the shifts observed in different months. The results showed significant differences in the composition and variation between iARGs and eARGs. Tetracycline, sulfonamide, and macrolide resistance genes were the major types of iARGs, while cfr was the major type of eARG. The environmental adaptations of the host bacteria determine whether ARGs appear as intracellular or extracellular forms. The total abundance of ARGs was higher from April to September, which can be attributed to the favorable climatic conditions for bacterial colonization and increased antibiotic administration during this period. Integron was found to be highly correlated with most iARGs, potentially playing a role in the presence of these genes within cells and their similar transmission patterns in wastewater. The intracellular and extracellular bacterial communities were significantly different, primarily because of variations in bacterial adaptability to the high salt and anaerobic environment. The intracellular co-occurrence network indicated that some dominant genera in wastewater, such as Turicibacter, Clostridium IV, Cloacibacillus, Subdivision5_genera_incertae_sedis, Saccharibacteria_genera_incertae_sedis and Halomonas, were potential hosts for many ARGs. To the best of our knowledge, this study demonstrates, for the first time, the annual variation of ARGs at critical points in the reuse of dairy farm wastewater. It also offers valuable insights into the prevention and control of ARGs derived from animals

Self-anti-angiogenesis nanoparticles enhance anti-metastatic-tumor efficacy of chemotherapeutics

Beyond traditional endothelium-dependent vessel (EDV), vascular mimicry (VM) is another critical tumor angiogenesis that further forms in many malignant metastatic tumors. However, the existing anti-angiogenesis combined chemotherapeutics strategies are only efficient for the treatment of EDV-based subcutaneous tumors, but remain a great challenge for the treatment of in situ malignant metastatic tumor associated with EDV and VM. Here, we demonstrate a self-assembled nanoparticle (VE-DDP-Pro) featuring self-anti-EDV and -VM capacity enables to significantly enhance the treatment efficacy of cisplatin (DDP) against the growth and metastasis of ovarian cancer. The VE-DDP-Pro is constructed by patching DDP loaded cRGD-folate-heparin nanoparticles (VE) onto the surface of protamine (Pro) nanoparticle. We demonstrated the self-anti-angiogenesis capacity of VE-DDP-Pro was attributed to VE, which could significantly inhibit the formation of EDV and VM by regulating signaling pathway of MMP-2/VEGF, AKT/mTOR/MMP-2/Laminin and AKT/mTOR/EMT, facilitating chemotherapeutics to effectively suppress the development and metastasis of ovarian cancer. Thus, combing with the chemotherapeutics effectiveness of DDP, the VE-DDP-Pro can significantly enhance treatment efficacy and prolong median survival of mice with metastatic ovarian cancer. We believe our self-assembled nanoparticles integrating the anti-EDV and anti-VM capacity provide a new preclinical sight to enhance the efficacy of chemotherapeutics for the treatment malignant metastasis tumor