Adapting the inoculation methods of kiwifruit canker disease to identify efficient biocontrol bacteria from branch microbiome.

Pseudomonas syringae pv. actinidiae (Psa), the bacterium that causes kiwifruit bacterial canker, is a common field occurrence that is difficult to control globally. Currently, exploring the resources for efficient biocontrol bacteria is a hot spot in the field. The common strategy for isolating biocontrol bacteria is to directly isolate biocontrol bacteria that can secrete diffusible antibacterial substances, most of which are members of Bacillus, Pseudomonas and Streptomycetaceae, from disease samples or soil. Here, we report a new approach by adapting the typical isolation methods of kiwifruit canker disease to identify efficient biocontrol bacteria from the branch microbiome. Using this unique approach, we isolated a group of kiwifruit biocontrol agents (KBAs) from the branch microbiome of Psa-resistant varieties. Thirteen of these showed no antagonistic activity in vitro, which depends on the secretion of antibacterial compounds. However, they exhibited antibacterial activity via cell-to-cell contacts mimicked by co-culture on agar plates. Through biocontrol tests on plants, two isolates, KBA13 and KBA19, demonstrated their effectiveness by protecting kiwifruit branches from Psa infection. Using KBA19, identified as Pantoea endophytica, as a representative, we found that this bacterium uses the type VI secretion system (T6SS) as the main contact-dependent antibacterial weapon that acts via translocating toxic effector proteins into Psa cells to induce cell death, and that this capacity expressed by KBA19 is common to various Psa strains from different countries. Our findings highlight a new strategy to identify efficient biocontrol agents that use the T6SS to function in an antibacterial metabolite-independent manner to control wood diseases.

Progress and perspectives of platinum nanozyme in cancer therapy.

Malignant tumors, one of the worst-case scenarios within human health problems, are now posing an increasing threat to the well-being of the global population. At present, the treatment of malignant tumors mainly includes surgery, radiotherapy, chemotherapy, immunotherapy, etc. Radiotherapy and chemotherapy are often applied to inoperable tumors, and some other tumors after surgery as important adjuvant therapies. Nonetheless, both radiotherapy and chemotherapy have a series of side effects, such as radiation-induced lung injury, and chemotherapy-induced bone marrow suppression. In addition, the positioning accuracy of radiotherapy and chemotherapy is not assured and satisfactory, and the possibility of tumor cells not being sensitive to radiation and chemotherapy drugs is also problematic. Nanozymes are nanomaterials that display natural enzyme activities, and their applications to tumor therapy have made great progress recently. The most studied one, platinum nanozyme, has been shown to possess a significant correlation with radiotherapy sensitization of tumors as well as photodynamic therapy. However, there are still several issues that limited the usage of platinum-based nanozymes in vivo. In this review, we briefly summarize the representative studies regarding platinum nanozymes, and especially emphasize on the current challenges and the directions of future development for platinum nanozymes therapy.

Effects of home-based exercise on exercise capacity, symptoms, and quality of life in patients with lung cancer: A meta-analysis.

PURPOSE: The aim of this study was to evaluate the effects of home-based exercise on exercise capacity, cancer-related fatigue, insomnia, pain, appetite loss, coughing, anxiety, depression, and quality of life of patients with lung cancer. METHODS: We conducted a search using English and Chinese databases, namely PubMed, Web of Science, Embase, ProQuest, the Cochrane Library, China National Knowledge Infrastructure (CNKI), Chinese Biomedical Literature (CBM), Wanfang Data, and China Science and Technology Journal Database (VIP) up to December 4, 2018. We selected randomized controlled trials and quasi-experimental trials that compared the effects of home-based exercise and routine guidance on exercise capacity, cancer-related fatigue, insomnia, pain, appetite loss, coughing, anxiety, depression, and quality of life of patients with lung cancer. The effect size was calculated using mean difference and 95% confidence interval, data were analyzed using the Stata version 12.0 software. RESULTS: We retrieved seven randomized controlled trials and seven quasi-experimental trials involving 694 patients in total. Home-based exercise significantly improved exercise capacity, reduced cancer-related fatigue, insomnia, anxiety, and depression, and improved quality of life (P < .05). However, it did not significantly reduce pain, appetite loss, and coughing symptoms (P > .05). CONCLUSIONS: Home-based exercise is a beneficial approach to improving exercise capacity, some symptoms, and quality of life of patients with lung cancer. Home-based exercise should be routinely recommended by health professionals when patients with lung cancer are discharged from hospital.