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The bacteria that dominate and become enriched in the rhizosphere during continuous cropping are of increasing interest, as they can greatly adapt to the rhizosphere. However, there are still little knowledge about the general composition and function of these bacteria. In this study, we planted tomatoes in three different soils for three planting cycles and used both high-throughput sequencing and culture-dependent workflows. Despite significant differences in bacterial communities from the initial soils, we observed a similar succession in the rhizosphere bacterial community compositions. We identified certain bacteria that were gradually enriched and potentially beneficial, such as Rhizobium and Flavobacterium. However, some other potentially beneficial bacteria, such as Massilia and Lysobacter, were gradually depleted. Additionally, we found that predicted functions related to xenobiotic biodegradation, nutrient metabolism and antibiotic biosynthesis were enriched in different rhizosphere soils. Beijerinckia fluminensis GR2, which was gradually enriched in all tested soils, significantly inhibited the growth of Ralstonia solanacearum and protected the host from infection. Our study provides new insights into the assembly mechanism of gradually enriched bacteria and their role as plant-beneficial microbes that adapt well to the rhizosphere. [ABSTRACT FROM AUTHOR]

Summary: Rhizomicrobiome plays important roles in plant growth and health, contributing to the sustainable development of agriculture. Plants recruit and assemble the rhizomicrobiome to satisfy their functional requirements, which is widely recognized as the 'cry for help' theory, but the intrinsic mechanisms are still limited.In this study, we revealed a novel mechanism by which plants reprogram the functional expression of inhabited rhizobacteria, in addition to the de novo recruitment of soil microbes, to satisfy different functional requirements as plants grow. This might be an efficient and low‐cost strategy and a substantial extension to the rhizomicrobiome recruitment theory.We found that the plant regulated the sequential expression of genes related to biocontrol and plant growth promotion in two well‐studied rhizobacteria Bacillus velezensis SQR9 and Pseudomonas protegens CHA0 through root exudate succession across the plant developmental stages. Sixteen key chemicals in root exudates were identified to significantly regulate the rhizobacterial functional gene expression by high‐throughput qPCR.This study not only deepens our understanding of the interaction between the plant–rhizosphere microbiome, but also provides a novel strategy to regulate and balance the different functional expression of the rhizomicrobiome to improve plant health and growth. [ABSTRACT FROM AUTHOR]

Background: Some degree of platelet index abnormality has been found clinically in the autoimmune thyroid disease (AITD), but the findings are not uniform. Methods: The PubMed, Web of Science, Cochrane Library, and Embase databases were searched for relevant articles published up to August 16th, 2022, with no restrictions on the language of the articles. Reference lists of eligible articles were also searched. A random effect model was used to pool the standardized mean difference (SMD) and 95% confidence interval (95% CI) of platelet count (PLT), mean platelet volume (MPV), and platelet distribution width (PDW) between AITD patients and healthy controls, and subgroup analyses were performed. Results: A total of 19 articles with 6173 people (3824 AITD patients and 2349 healthy people) were included in the meta-analysis. The results showed that PLT and MPV values were significantly increased in AITD patients when compared with healthy people (SMD: 0.164, 95% CI: 0.044 to 0.285; SMD: 0.256, 95% CI: 0.013 to 0.500), while no significant difference was found in PDW between the AITD group and the control group (SMD: 0.060, 95% CI: -0.164 to 0.284). Subgroup analysis according to disease type and thyroid function revealed that for PLT, this difference was only found in the Hashimoto's thyroiditis (HT) and hypothyroid groups, but not in the Graves' disease (GD) and hyperthyroid groups. For MPV, the results were the opposite of those for PLT: MPV was significantly higher in the GD, hyperthyroid, and euthyroid groups than in the control group, but not in the HT and hypothyroid groups. Sensitivity analysis showed that the stability of the pooled MPV was not good. No publication bias was found. Conclusions: PLT and MPV are significantly elevated in patients with AITD, with PLT being more significantly elevated in HT and hypothyroidism, and MPV being more significantly increased in GD and hyperthyroidism. Appropriate clinical attention can be paid to the thyroid function of patients when abnormal platelet indices are found, and conversely, the consequences of abnormal platelet parameters such as elevated MPV lead to an increased occurrence of cardiovascular events, which should also be addressed in the AITD population. [ABSTRACT FROM AUTHOR]

High-throughput sequencing, culture-dependent workflows, and microbiome transfer experiments reveal whether potassium phosphite (KP), an environmentally acceptable agricultural chemical, could specifically enrich the antagonistic bacterial community that inhibited the growth of the pathogen Ralstonia solanacearum. The application of KP enriched the potential antagonistic bacteria Paenibacillus and Streptomyces in soil, but depleted most dominant genera belonging to gram negative bacteria, such as Pseudomonas, Massilia, and Flavobacterium on day 7. Moreover, the KP-modulated soil microbiome suppressed R. solanacearum growth in soil. The predicted functions related to the synthesis of antagonistic substances, such as streptomycin, and the predicted functions related to tellurite resistance and nickel transport system were significantly enriched, but the synthesis of lipopolysaccharide (distinct component lipopolysaccharide in gram negative bacteria) were significantly depleted in the KP-treated soils. In addition, the copy numbers of specific sequences for Streptomyces coelicoflavus and Paenibacillus favisporus were significantly increased in the soil amended with KP, inhibited the growth of R. solanacearum, and had a higher tolerance of KP than R. solanacearum. Our study linked the application of fertilizers to the enrichment of antagonistic bacteria, which could support future work that aims to precisely regulate the soil microbiome to protect the host from infection by soil-borne pathogens. [ABSTRACT FROM AUTHOR]

An efficient synthesis of 2-amino-3-methylenephthalimide through palladium-catalyzed intramolecular aminocarbonylation has been developed. The reaction carried out under atmospheric pressure of CO and provided diversified 2-amino-3-methylenephthalimides in reasonable to good yields from o-iodoacetophenone phenylhydrazone, which are readily derived from phenylhydrazines and 2-iodoacetophenones. [ABSTRACT FROM AUTHOR]

Abstract: In the past decades, C−H oxidative olefination of indole at C‐2, C‐3, C‐4 and C‐7 positions was well addressed. We report here a rhodium‐catalyzed NH‐indole‐directed ortho C−H bond olefination of 2‐arylindoles. This cross‐dehydrogenative‐coupling proved to be broad in substrate scope, tolerating a variety of functional groups. The synthesis of 6H‐isoindolo[2,1‐α]indoles via rhodium‐catalyzed ortho C−H olefination and subsequent intramolecular aza‐Michael reaction of 2‐arylindoles was also demonstrated. [ABSTRACT FROM AUTHOR]

Based on the mode-coupling method, numerical analysis is presented to demonstrate the influence of ripple taper on coupling modes on the frequency response in a coaxial Bragg structure. Results show that the interval between the band-gaps of the competing mode and the desired working mode is narrowed by use of a positive taper, but is expanded if a negative taper is employed, and the influence of the negative taper is more obviously advantage than the positive taper. The residual side-lobes of the frequency response on coupling modes can be effectively suppressed by employing the windowing-function technique. These characteristics of a tapered coaxial Bragg structure are favorable to improvement of the performance as a reflector or a filter in its application, also favorable to the mode selectivity and further weaken the excitation of unwanted spurious modes. [ABSTRACT FROM AUTHOR]

Soil-borne pathogen invasions can significantly change the microbial communities of the host rhizosphere. However, whether bacterial Ralstonia solanacearum pathogen invasion influences the abundance of fungal pathogens remains unclear. In this study, we combined high-throughput sequencing, qPCR, liquid chromatography and soil culture experiments to analyze the rhizosphere fungal composition, co-occurrence of fungal communities, copy numbers of functional genes, contents of phenolic acids and their associations in healthy and bacterial wilt-diseased tomato plants. We found that R. solanacearum invasion increased the abundance of the soil-borne pathogen Fusarium solani. The concentrations of three phenolic acids in the rhizosphere soil of bacterial wilt-diseased tomato plants were significantly higher than those in the rhizosphere soil of healthy tomato plants. In addition, the increased concentrations of phenolic acids significantly stimulated F. solani growth in the soil. Furthermore, a simple fungal network with fewer links, nodes and hubs (highly connected nodes) was found in the diseased tomato plant rhizosphere. These results indicate that once the symptom of bacterial wilt disease is observed in tomato, the roots of the wilt-diseased tomato plants need to be removed in a timely manner to prevent the enrichment of other fungal soil-borne pathogens. These findings provide some ecological clues for the mixed co-occurrence of bacterial wilt disease and other fungal soil-borne diseases. [ABSTRACT FROM AUTHOR]