The B-box transcription factor BnBBX22.A07 enhances salt stress tolerance by indirectly activating BnWRKY33.C03.

Salt stress has a detrimental impact on both plant growth and global crop yields. B-box proteins have emerged as pivotal players in plant growth and development regulation. Although the precise role of B-box proteins orchestrating salt stress responses in B. napus (Brassica napus) is not well understood in the current literature, further research and molecular explorations are required. Here, we isolated the B-box protein BnBBX22.A07 from B. napus. The overexpression of BnBBX22.A07 significantly improved the salt tolerance of Arabidopsis (Arabidopsis thaliana) and B. napus. Transcriptomic and histological analysis showed that BnBBX22.A07 enhanced the salt tolerance of B. napus by activating the expression of reactive oxygen species (ROS) scavenging-related genes and decreasing salt-induced superoxide anions and hydrogen peroxide. Moreover, BnBBX22.A07 interacted with BnHY5.C09, which specifically bound to and activated the promoter of BnWRKY33.C03. The presence of BnBBX22.A07 enhanced the activation of BnHY5.C09 on BnWRKY33.C03. Overexpression of BnHY5.C09 and BnWRKY33.C03 improved the salt tolerance of Arabidopsis. Functional analyses revealed that BnBBX22.A07-mediated salt tolerance was partly dependent on WRKY33. Taken together, we demonstrate that BnBBX22.A07 functions positively in salt responses not only by activating ROS scavenging-related genes but also by indirectly activating BnWRKY33.C03. Notably, our study offers a promising avenue for the identification of candidate genes that could be harnessed in breeding endeavours to develop salt-resistant transgenic crops.

Identification of Alkaline Salt Tolerance Genes in Brassica napus L. by Transcriptome Analysis.

Soil salt alkalization is one major abiotic factor reducing the productivity of crops, including rapeseed, an indispensable oil crop and vegetable. The mechanism studies of alkali salt tolerance can help breed highly resistant varieties. In the current study, rapeseed (B. napus) line 2205 exhibited more tolerance to alkaline salt than line 1423 did. In line 2205, the lesser plasma membrane damage index, the accumulated osmotic solute, and higher antioxidant enzyme activities contributed to alkaline tolerance. A more integrated mesophyll-cell structure was revealed under alkali salt stress by ultrastructure observation in line 2205, which also implied a lesser injury. Transcriptome analysis showed that more genes responded to alkaline salt in line 2205. The expression of specific-response genes in line 1423 was lower than in line 2205. However, most of the specific-response genes in line 2205 had higher expression, which was mainly enriched in carbohydrate metabolism, photosynthetic processes, ROS regulating, and response to salt stress. It can be seen that the tolerance to alkaline salt is attributed to the high expression of some genes in these pathways. Based on these, twelve cross-differentially expressed genes were proposed as candidates. They provide clues for further analysis of the resistance mechanism of rapeseed.

A retrospective cohort study of disease-related risk factors for central venous catheter-related symptomatic thrombosis in intensive care unit inpatients.

ABSTRACT: Central venous catheters (CVC) are widely used in critically ill patients given their benefits in monitoring vital signs, treatment administration, and renal replacement therapy in intensive care unit (ICU) patients, but these catheters have the potential to induce symptomatic catheter-related venous thrombosis (CRVT). This study reported the rate of symptomatic CRVT in ICU patients receiving CVC and analyzed the disease-related risk factors for symptomatic CRVT in ICU patients.A retrospective analysis was performed on the consecutive ICU 1643 critically ill patients with CVCs inserted from January 2015 to December 2019. Symptomatic CRVT was confirmed by ultrasound. CVCs were divided into 2 groups based on the presence of symptomatic CRVT, and the variables were extracted from the electronic medical record system. Logistic univariate and multivariate regression analyses were used to determine the disease-related risk factors of symptomatic CRVT.A total of 209 symptomatic CRVT events occurred among 2114 catheters. The rate of CRVT was 9.5 per 1000 catheter days. Univariate analysis revealed that trauma, major surgery, heart failure, respiratory failure, and severe acute pancreatitis were risk factors for symptomatic CRVT in the ICU. Multivariate analysis showed that trauma (odds ratio [OR], 2.046; 95% confidence interval [CI] [1.325-3.160], P = .001), major surgery (OR, 2.457; 95% CI [1.641-3.679], P = .000), and heart failure (OR, 2.087; 95% CI [1.401-3.111], P = .000) were independent disease-related risk factors for symptomatic CRVT in ICU. The C-statistic for this model was 0.61 (95% CI [0.57-0.65], P = .000).The incidence rate of symptomatic CRVT in the ICU population was 9.5 per 1000 catheter days. Trauma, major surgery, and heart failure are independent disease-related risk factors of symptomatic CRVT.

Effects of humic acid on the interactions between zinc oxide nanoparticles and bacterial biofilms.

The effects of humic acid (HA) on interactions between ZnO nanoparticles (ZnO NPs) and Pseudomonas putida KT2440 biofilms at different maturity stages were investigated. Three stages of biofilm development were identified according to bacterial adenosine triphosphate (ATP) activity associated with biofilm development process. In the initial biofilm stage 1, the ATP content of bacteria was reduced by more than 90% when biofilms were exposed to ZnO NPs. However, in the mature biofilm stages 2 and 3, the ATP content was only slightly decreased. Biofilms at stage 3 exhibited less susceptibility to ZnO NPs than biofilms at stage 2. These results suggest that more mature biofilms have a significantly higher tolerance to ZnO NPs compared to young biofilms. In addition, biofilms with intact extracellular polymeric substances (EPS) showed higher tolerance to ZnO NPs than those without EPS, indicating that EPS play a key role in alleviating the toxic effects of ZnO NPs. In both pure ZnO NPs and ZnO-HA mixtures, dissolved Zn2+ originating from the NPs significantly contributed to the overall toxicity. The presence of HA dramatically decreased the toxicity of ZnO NPs due to the binding of Zn2+ on HA. The combined results from this work suggest that the biofilm maturity stages and environmental constituents (such as humic acid) are important factors to consider when evaluating potential risks of NPs to ecological systems.

A lectin-based isolation/enrichment strategy for improved coverage of N-glycan analysis.

Glycomics provides an increasingly useful research tool as the genomes and proteomes of more and more animal species are elucidated. In view of the general complexity and heterogeneity of glycans, improved depth-of-coverage and sensitivity are required for glycosylation analysis. In this study, we established the lectin-based isolation/enrichment strategy for total glycomic information. Specific lectins are added onto the filter to capture corresponding glycans prior to release of N-glycans by peptide N-glycosidase F (PNGase F). Non-bound glycans and bound glycans are released and analyzed by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS), respectively. Application of the strategy to chicken ovalbumin, normal mouse mammary epithelial cells (NMuMG), and human serum resulted in detection of 5, 6, and 11 additional N-glycan structures, respectively. The strategy facilitates identification of intact N-glycans in biological samples, and can be extended to detailed analysis of O-glycome or glycoproteome.