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The adsorption of organic pollutants by soil has an important impact on their migration, transformation and bioavailability. Black soil is rich in organic matter that plays an essential role in adsorption, which indicates that black soil may have a high adsorption capacity for DBP. The significant DBP adsorption capacity of black soil was discovered through research into the adsorption kinetics and thermodynamic properties of DBP in black soil. This finding was consistent with pseudo-second-order kinetics. The adsorption was chemical adsorption, and intramolecular diffusion was a critical control step in the adsorption process. The adsorption equilibrium time was 24 h. Analyzing the effects of temperature, pH, ionic strength and other conditions, it was found that reducing the temperature promoted the adsorption of DBP. When the pH was 7, the adsorption capacity was the greatest. The capacity of DBP to adsorb was boosted by the rise in ionic strength, which also hindered DBP adsorption once it reached a certain threshold.

We explored the composition and roles of the protein phosphatase 2C (PP2C) family in Paulownia fortunei. The genome P. fortunei harbored 91 PfPP2C genes, encoding proteins with 120–1107 amino acids (molecular weight range, 13.51–124.81 kDa). The 91 PfPP2Cs were distributed in 12 subfamilies, with 1–15 PfPP2Cs per subfamily. The number and types of conserved structure domains differed among PP2Cs, but the distribution of conserved motifs within each subfamily was similar, with the main motif structure being motifs 3, 16, 13, 10, 2, 6, 12, 4, 14, 1, 18, and 8. The PfPP2C genes had 2 to 20 exons. There were ABA-response elements in the promoters of 42 PfPP2C genes, response elements to phytohormones, and stress in the promoters of other PfPP2C genes. A covariance analysis revealed that gene fragment duplication has played an important role in the evolution of the PfPP2C family. There were significant differences in the transcript levels of some PfPP2C genes in P. fortunei affected by witches’ broom (PaWB) and after treatment with rifampicin and methyl methanesulfonate. PfPP2C02, PfPP2C12, PfPP2C19, and PfPP2C80 were strongly related to PaWB. These findings provide a foundation for further studies on the roles of PP2Cs in PaWB.

Paulownia witches’ broom (PaWB), caused by phytoplasmas, is the most devastating infectious disease of Paulownia. R2R3-MYB transcription factors (TF) have been reported to be involved in the plant’s response to infections caused by these pathogens, but a comprehensive study of the R2R3-MYB genes in Paulownia has not been reported. In this study, we identified 138 R2R3-MYB genes distributed on 20 chromosomes of Paulownia fortunei. These genes were classified into 27 subfamilies based on their gene structures and phylogenetic relationships, which indicated that they have various evolutionary relationships and have undergone rich segmental replication events. We determined the expression patterns of the 138 R2R3-MYB genes of P. fortunei by analyzing the RNA sequencing data and found that PfR2R3-MYB15 was significantly up-regulated in P. fortunei in response to phytoplasma infections. PfR2R3-MYB15 was cloned and overexpressed in Populus trichocarpa. The results show that its overexpression induced branching symptoms. Subsequently, the subcellular localization results showed that PfR2R3-MYB15 was located in the nucleus. Yeast two-hybrid and bimolecular fluorescence complementation experiments showed that PfR2R3-MYB15 interacted with PfTAB2. The analysis of the PfR2R3-MYB15 gene showed that it not only played an important role in plant branching, but also might participate in the biosynthesis of photosystem elements. Our results will provide a foundation for future studies of the R2R3-MYB TF family in Paulownia and other plants.

Paulownia witches’ broom (PaWB), caused by phytoplasmas, is the most devastating infectious disease of Paulownia. Although a few MADS-box transcription factors have been reported to be involved in the formation of PaWB, there has been little investigation into all of the MADS-box gene family in Paulownia. The objective of this study is to identify the MADS-box gene family in Paulownia fortunei on a genome-wide scale and explore their response to PaWB infection. Bioinformatics software were used for identification, characterization, subcellular localization, phylogenetic analysis, the prediction of conserved motifs, gene structures, cis-elements, and protein-protein interaction network construction. The tissue expression profiling of PfMADS-box genes was analyzed by quantitative real-time polymerase chain reaction (qRT-PCR). Transcriptome data and the protein interaction network prediction were combined to screen the genes associated with PaWB formation. We identified 89 MADS-box genes in the P. fortunei genome and categorized them into 14 subfamilies. The comprehensive analysis showed that segment duplication events had significant effects on the evolution of the PfMADS-box gene family; the motif distribution of proteins in the same subfamily are similar; development-related, phytohormone-responsive, and stress-related cis-elements were enriched in the promoter regions. The tissue expression pattern of PfMADS-box genes suggested that they underwent subfunctional differentiation. Three genes, PfMADS3, PfMADS57, and PfMADS87, might be related to the occurrence of PaWB. These results will provide a valuable resource to explore the potential functions of PfMADS-box genes and lay a solid foundation for understanding the roles of PfMADS-box genes in paulownia–phytoplasma interactions.

Background The monitoring of anti-p53 auto-antibodies in the peripheral blood has been used in cancer management; however, their clinical significance alone is limited. This pilot study aimed to describe the prevalence of elevated anti-p53 in newly diagnosed or recurrent upper gastrointestinal cancer or colorectal cancer in Chinese subjects. It also evaluated whether the addition of anti-p53 to a set of established tumor markers would allow for the detection of additional cancer cases than when using these markers alone. Methods A total of 573 subjects, including 187 healthy individuals, 169 patients with upper gastrointestinal cancer and 217 patients with colorectal cancer were included in this observational, prospective study. All subjects were required to provide up to 10 mL of blood. The following biomarkers were measured: anti-p53, carcinoembryonic antigen, cancer antigen (CA)19-9, and CA72-4. Results At the cutoff of 0.02 µg/mL, the sensitivity of anti-p53 in early-stage upper gastrointestinal cancer and colorectal cancer was 8.16% and 26.4%, and in late-stage disease was 7.81 and 28.0%, respectively. The specificity of anti-p53 in the healthy cohort at this cutoff was 98.4%. By adding anti-p53 to other tumor markers, the sensitivities were increased by 8.88%–9.47% in upper gastrointestinal cancer, and by 18.06%–25.00% in colorectal cancer; specificities decreased by 1%–2%. Conclusion The addition of anti-p53 to established tumor markers may improve their diagnostic value for patients with colorectal cancer.

Dynamic changes in total organic carbon (TOC) concentration in lakes and reservoirs affect the functions of aquatic ecosystems and are a key component of water quality management, especially in drinking water sources. The Danjiangkou Reservoir is the water source area of the Middle Route Project of the South-to-North Water Diversion in China. Its water quality is of critical importance to the safety of water diversion. TOC concentration and other environmental factors at 19 sampling sites in the Danjiangkou Reservoir were investigated quarterly during 2020–2021 to explore the differences at the spatio-temporal scales. A generalized additive model (GAM) was used to analyze the environmental factors correlated with the observed spatio-temporal variations of TOC concentration. The results showed that the comprehensive trophic level index (TLI) of the Danjiangkou Reservoir was under the state of intermediate nutrition, and the water quality was overall good. In terms of temporal patterns, TOC concentration was higher in both spring and summer and lower in other seasons. Spatially, TOC concentrations were found in descending order from the site of outlet, Han reservoir, entrance of reservoir, and Dan reservoir. The single-factor GAM model showed that TOC correlated with different environmental factors across spatio-temporal scales. Water temperature (WT), permanganate index (CODMn), and ammonia nitrogen (NH4+-N) were significantly correlated with TOC in autumn, but only total nitrogen (TN) and transparency (SD) were significant in winter. Spatially, WT, chemical oxygen demand (COD), NH4+-N, TN, and conductivity (Cond) correlated with TOC in the Dan reservoir, but WT, COD, NH4+-N, total phosphorus (TP), and chlorophyll a (Chl.a) were significant in the Han reservoir. The multi-factor GAM model indicated that the environmental factors correlated with TOC concentration were mainly WT, TN, Cond, CODMn, and TP, among which WT and Cond showed a significant linear relationship with TOC concentration (edf = 1, p < 0.05), while TN, CODMn, and TP had a significant nonlinear relationship with TOC concentration (edf > 1, p < 0.05). Comprehensive trophic level index (TLI) and TOC concentration revealed a highly significant correlation (R2 = 0.414, p < 0.001). Therefore, the GAM model could well explain the environmental factors associated with the spatio-temporal dynamics of TOC concentration, providing a reference for the evaluation of water quality and research on the carbon cycle in similar inland reservoirs.