Exposure to cypermethrin pesticide disturbs the microbiome and disseminates antibiotic resistance genes in soil and the gut of Enchytraeus crypticus.

Worldwide, pyrethroids, such as cypermethrin, are the second most applied group of insecticides, however, their effects on the soil microbiome and non-target soil fauna remain largely unknown. Herein, we assessed the change of bacterial communities and antibiotic resistance genes (ARGs) of soil and in the gut of the model soil species Enchytraeus crypticus using a combination of 16S rRNA gene amplicon sequencing, and high-throughput qPCR of ARGs. Results indicate that cypermethrin exposure enriches potential pathogens (e.g. Bacillus anthracis) in the soil and gut microbiome of E. crypticus, heavily disrupting the latter's microbiome structure, and even disrupts activities of the E. crypticus immune system. The co-occurrence of potential pathogens (e.g. Acinetobacter baumannii), ARGs, and mobile genetic elements (MGEs) revealed the increased risk of pathogenicity as well as antibiotic resistance in potential pathogens. Moreover, structural equation modeling demonstrated that the dissemination of ARGs was not only promoted by MGEs, but also by the ratio of the core to non-core bacterial abundance. Collectively, these results provide an in-depth view of the previously unappreciated environmental risk of cypermethrin on the dissemination of ARGs in the soil and non-target soil fauna.

ROS as a key player in quinolone antibiotic stress on Arabidopsis thaliana: From the perspective of photosystem function, oxidative stress and phyllosphere microbiome.

With the increasing use of antibiotics, their ecological impacts have received widespread attention. However, research on the toxicity of quinolone antibiotics is still limited, especially regarding the oxidative stress and phyllosphere of plants. In this study, the toxic effects of enrofloxacin, norfloxacin, and levofloxacin on Arabidopsis thaliana and their underlying mechanisms were investigated. The toxicity of the three quinolone antibiotics decreased in the following order: enrofloxacin > norfloxacin > levofloxacin. Physiological cellular changes, such as plasmolysis and chloroplast swelling, were observed using electron microscopy. Photosynthetic efficiency was inhibited with a decline in the effective photochemical quantum yield of photosystem II (Y(II)) and non-photochemical quenching (NPQ), indicating that quinolone antibiotics might reduce light energy conversion efficiency and excess light energy dissipation. Oxidative stress occurred in A. thaliana after quinolone antibiotic treatment, with an increase in reactive oxygen species (ROS) levels and malondialdehyde (MDA) content. High ROS levels stimulated the over-expression of superoxide-responsive genes for self-protection. Structural equation modeling (SEM) analysis showed that photosynthesis inhibition and cellular damage caused by oxidative stress were critical factors for growth inhibition, suggesting that the antioxidant response activated by ROS might be a potential mechanism. Furthermore, the diversity of the phyllospheric microbial communities decreased after enrofloxacin exposure. Additionally, specific microbes were preferentially recruited to the phyllosphere because of the higher ROS levels.

Bifidobacterium lactis BB-12 Attenuates Macrophage Aging Induced by D-Galactose and Promotes M2 Macrophage Polarization.

Immunosenescence comprises a set of dynamic changes occurring in innate and adaptive immune systems, and macrophage aging plays an important role in innate and adaptive immunosenescence. However, function and polarization changes in aging macrophages have not been fully evaluated, and no effective method for delaying macrophage senescence is currently available. The results of this study reveal that D-galactose (D-gal) can promote J774A.1 macrophage senescence and induce macrophage M1 polarization differentiation. Bifidobacterium lactis BB-12 can significantly inhibit J774A.1 macrophage senescence induced by D-gal. IL-6 and IL-12 levels in the BB-12 groups remarkably decreased compared with that in the D-gal group, and the M2 marker, IL-10, and Arg-1 mRNA levels increased in the BB-12 group. BB-12 inhibited the expression of p-signal transducer and activator of transcription 1 (STAT1) and promoted p-STAT6 expression. In summary, the present study indicates that BB-12 can attenuate the J774A.1 macrophage senescence and induce M2 macrophage polarization, thereby indicating the potential of BB-12 to slow down immunosenescence and inflamm-aging.

Bilateral pleural effusion as an initial manifestation of multiple myeloma: A case report and literature review.

Multiple myeloma (MM) is a rare type of malignant hematological neoplasm. Although primarily involving the bone marrow, MM has a significant risk of metastasizing to other organs and may present with various clinical symptoms. However, the involvement of the respiratory system in the course of MM is extremely uncommon, particularly presenting with bilateral pleural effusion as the sole initial manifestation, which may result in a delayed diagnosis of MM. The present study describes the extremely rare case of a patient with MM presenting with myelomatous pleural effusion (MPE). The 78-year-old patient was admitted to the Department of Respiratory Medicine, Taizhou People's Hospital (Taizhou, China) in March 2014, complaining of persistent dyspnea. Following admission, chest computed tomography scans revealed bilateral pleural effusion and a small amount of pericardial effusion, but no evident mass lesion. Thoracentesis was performed and the resulting pleural effusion was exudative and slightly bloody. In the following cytological examination, myeloma cells were identified in the pleural effusion. The patient was diagnosed definitively with MM following a histopathological study of the bone marrow aspiration. Therefore, the observations of the present case report may promote the consideration of MM in the differential diagnosis of patients with unexplained and refractory pleural effusion. The present study also reviewed the literature with regard to the association between MM and pleural effusion.