Overexpression of NtEXPA7 promotes seedling growth and resistance to root-knot nematode in tobacco.

Root-knot nematode (RKN) is one of the most damaging plant pathogen in the world. They exhibit a wide host range and cause serious crop losses. The cell wall, encasing every plant cell, plays a crucial role in defending of RKN invasion. Expansins are a group of cell wall proteins inducing cell wall loosening and extensibility. They are widely involved in the regulation of plant growth and the response to biotic and abiotic stresses. In this study, we have characterized the biological function of tobacco (Nicotiana tabacum) NtEXPA7, the homologue of Solyc08g080060.2 (SlEXPA18), of which the transcription level was significantly reduced in susceptible tomato upon RKN infection. The expression of NtEXPA7 was up-regulated after inoculation of RKNs. The NtEXPA7 protein resided in the cell wall. Overexpression of NtEXPA7 promoted the seedling growth of transgenic tobacco. Meanwhile the increased expression of NtEXPA7 was beneficial to enhance the resistance against RKNs. This study expands the understanding of biological role of expansin in coordinate plant growth and disease resistance.

The Ratio of Red Blood Cell Distribution Width to Albumin as a Predictor for Rehospitalization Risk and Rehospitalization All-Cause Mortality in Middle-Aged and Elderly Survivors with Sepsis: An Ambispective ICU Cohort Study.

Objective: To explore the relationship between red blood cell distribution width to albumin (RDW/ALB) ratio (RAR) and the risk of rehospitalization and rehospitalization all-cause mortality in middle-aged and elderly survivors with sepsis based on an ambispective longitudinal cohort from the Intensive Care Unit (ICU). Methods: Between 2017 and 2022, 455 adults who survived the first-episode severe sepsis without recurrence for at least 3 months were included in this study. All participants were followed up every 4 weeks for 12 months. According to the tertiles of RAR, participants were divided into three groups: low-level (≤0.36, n = 152), moderate-level (0.37-0.44, n = 152), and high-level (≥0.45, n = 151). The relationship between RAR and the risk of rehospitalization and rehospitalization all-cause mortality was evaluated. Results: Out of 455 participants, 156 experienced rehospitalization (34.3%), of which 44 (28.2%) died. Receiver operating characteristic (ROC) analysis showed that the RAR cut-off values for rehospitalization and rehospitalization all-cause mortality were 0.4251 and 0.4743, respectively. Multivariate Cox regression analysis indicated that the RAR was positively associated with rehospitalization (P = 0.011) and all-cause mortality (P = 0.006). Compared with the low-level, the high-level RAR presented a higher dose-dependent rehospitalization risk (P = 0.02) and rehospitalization all-cause mortality (P = 0.044). The stratified analysis displayed that compared to the low-level, with the RAR increasing by 1.0, the risk for rehospitalization increased 3.602-fold in aged <65 patients (P = 0.002) and 1.721-fold in female patients (P = 0.014). Kaplan-Meier survival analysis implied a significant positive association between the RAR and the cumulative incidence of rehospitalization and rehospitalization all-cause mortality (log-rank, all P < 0.001). Conclusion: RAR has a reliable predictive value for the risk of rehospitalization and rehospitalization all-cause mortality in patients with sepsis. Consequently, monitoring RAR for at least 1 year after surviving sepsis in female patients aged <65 in clinical practice is critical.

Effects of Superfine Tricalcium Silicate Powder on the Physicochemical and Mechanical Properties of Its Premixed Cement as a Root Canal Filling Material.

Calcium silicate-based cement is a promising material for filling root canals. However, it has several drawbacks to its clinical application, including difficult operation and low curing strength. In this study, we successfully prepared an ultrafine tricalcium silicate powder and investigated the effects of this ultrafine powder on the performance of the premixed tricalcium silicate cement, including the curing process, setting time, hydration products, microstructure, injectivity, fluidity, and compressive strength. The results demonstrate that the addition of ultrafine tricalcium silicate powder alters the hydration product content and product morphology of the premixed cement. By increasing the content of the ultrafine powder, the injectable property of the cement can be increased to more than 95%, the fluidity can be increased from 18 mm to 35 mm, and the curing time can be shortened from 13 h to 11 h. Notably, the addition of the ultrafine powder greatly enhances the compressive strength of the hardened cement, which increases from 20.6 MPa to 51.0 MPa. These results indicate that altering the particle size distribution of the powder is an effective method for enhancing the physicochemical and mechanical properties of tricalcium silicate cement as a root canal filling material.

Diversity of endosymbionts in camellia spiny whitefly, Aleurocanthus camelliae (Hemiptera: Aleyrodidae), estimated by 16S rRNA analysis and their biological implications.

Camellia spiny whitefly, Aleurocanthus camelliae (Hemiptera: Aleyrodidae), is a major pest in tea, which poses a serious threat to tea production. Similar to many insects, various bacterial symbioses inside A. camelliae may participate in the reproduction, metabolism, and detoxification of the host. However, few reports included research on the microbial composition and influence on A. camelliae growth. We first applied high-throughput sequencing of the V4 region in the 16S rRNA of symbiotic bacteria to study its component and effect on the biological trait of A. camelliae by comparing it with the antibiotic treatment group. The population parameters, survival rate, and fecundity rate of A. camelliae were also analyzed using the age-stage two-sex life table. Our results demonstrated that phylum Proteobacteria (higher than 96.15%) dominated the whole life cycle of A. camelliae. It unveiled the presence of Candidatus Portiera (primary endosymbiont) (67.15-73.33%), Arsenophonus (5.58-22.89%), Wolbachia (4.53-11.58%), Rickettsia (0.75-2.59%), and Pseudomonas (0.99-1.88%) genus. Antibiotic treatment caused a significant decrease in the endosymbiont, which negatively affected the host's biological properties and life process. For example, 1.5% rifampicin treatment caused a longer preadult stage in the offspring generation (55.92 d) compared to the control (49.75d) and a lower survival rate (0.36) than the control (0.60). The decreased intrinsic rate of increase (r), net reproductive rate (R 0), and prolonged mean generation time (T) were signs of all disadvantageous effects associated with symbiotic reduction. Our findings confirmed the composition and richness of symbiotic bacteria in larva and adult of A. camelliae by an Illumina NovaSeq 6000 analysis and their influence on the development of the host by demographic research. Together, the results suggested that symbiotic bacteria play an important role in manipulating the biological development of their hosts, which might help us for developing new pest control agents and technologies for better management of A. camelliae.

Design, Synthesis and Bioactivity of Novel Pyrimidine Sulfonate Esters Containing Thioether Moiety.

Pesticides play an important role in crop disease and pest control. However, their irrational use leads to the emergence of drug resistance. Therefore, it is necessary to search for new pesticide-lead compounds with new structures. We designed and synthesized 33 novel pyrimidine derivatives containing sulfonate groups and evaluated their antibacterial and insecticidal activities. Results: Most of the synthesized compounds showed good antibacterial activity against Xanthomonas oryzae pv. Oryzae (Xoo), Xanthomonas axonopodis pv. Citri (Xac), Pseudomonas syringae pv. actinidiae (Psa) and Ralstonia solanacearum (Rs), and certain insecticidal activity. A5, A31 and A33 showed strong antibacterial activity against Xoo, with EC50 values of 4.24, 6.77 and 9.35 µg/mL, respectively. Compounds A1, A3, A5 and A33 showed remarkable activity against Xac (EC50 was 79.02, 82.28, 70.80 and 44.11 µg/mL, respectively). In addition, A5 could significantly improve the defense enzyme (superoxide dismutase, peroxidase, phenylalanine ammonia-lyase and catalase) activity of plants against pathogens and thus improve the disease resistance of plants. Moreover, a few compounds also showed good insecticidal activity against Plutella xylostella and Myzus persicae. The results of this study provide insight into the development of new broad-spectrum pesticides.

Highly water-stable bimetallic organic framework MgCu-MOF74 for inhibiting bacterial infection and promoting bone regeneration.

As a typical metal-organic framework (MOF), Mg-MOF74 can release biocompatible Mg2+when the framework is degraded, and it has the potential to be used as filler in the field of bone tissue engineering. However, Mg-MOF74 has poor stability in aqueous environment and limited antibacterial ability, which limit its further development and applications. In this work, MgCu-MOF74 particles with different Cu content were synthesized through a facile one-step hydrothermal method. The physicochemical properties and water stability of the synthesized powders were characterized. The osteogenic potential of the MgCu-MOF74 particles on human osteogenic sarcoma cells (SaOS-2) was evaluated. The hybrid MgCu-MOF74 exhibited favorable water stability. These results indicated that MgCu-MOF74 enhanced cellular viability, alkaline phosphatase levels, collagen (COL) synthesis and osteogenesis-related gene expression. Moreover, the samples doped with Cu2+were more sensitive to the acidic microenvironment produced by bacteria, and exhibited stronger antibacterial ability than Mg-MOF74. In conclusion, MgCu-MOF-74 with good water stability, osteogenic ability and antibacterial ability, which could be attributed to the doping of Cu2+. Hence, MgCu-MOF74 shows great potential as a novel medical bio-functional fillers for the treatment of bone defects.

Simultaneously stimulated osteogenesis and anti-bacteria of physically cross-linked double-network hydrogel loaded with MgO-Ag2O nanocomposites.

Hydrogels, with a three-dimensional network of water-soluble polymer and water, could simulate the critical properties of extracellular matrix, which has been widely used in bone tissue engineering. However, most of conventional hydrogels for bone regeneration are fragile and have poor osteogenic activity, which restricts their applications. In this work, a novel nanoparticle-hydrogel composite consisting of physically cross-linked double-network loaded with MgO-Ag2O nanocomposites was developed by the sol-gel method. The Mg2+ released from MgO-Ag2O nanocomposites was used as an ionic cross-linking site of sodium alginate (SA), while the hydrophobic micelles in the polyacrylamide (PAAM) network is acted as another crosslinking point. The results indicated that the novel nanoparticle-hydrogel composites had good self-recovery ability and excellent mechanical properties compared with the conventional sodium alginate (SA)/polyacrylamide (PAAM) hydrogels. Additionally, it showed a slow release of Mg and Ag ions due to the dual function of the embedding effect of hydrogels and the increasing pH of the solution induced by the hydrolysis of sodium alginate. In terms of in vitro tests, the nanoparticle-hydrogel composites showed significantly stimulatory effects on the proliferation and differentiation of SaOS-2 cells. In addition, the antibacterial effects of the nanoparticle-hydrogel composites were gradually enhanced with the increase of MgO-Ag2O content.

Retraction notice to "Amelioration of imiquimod-induced psoriasis-like dermatitis in mice by DSW therapy inspired hydrogel" [BIOMAT 6 (2021) 299-311].

[This retracts the article DOI: 10.1016/j.bioactmat.2020.08.007.].

Transcriptomic and Metabolomic Analysis Reveal Possible Molecular Mechanisms Regulating Tea Plant Growth Elicited by Chitosan Oligosaccharide.

Chitosan oligosaccharide (COS) plays an important role in the growth and development of tea plants. However, responses in tea plants trigged by COS have not been thoroughly investigated. In this study, we integrated transcriptomics and metabolomics analysis to understand the mechanisms of chitosan-induced tea quality improvement and growth promotion. The combined analysis revealed an obvious link between the flourishing development of the tea plant and the presence of COS. It obviously regulated the growth and development of the tea and the metabolomic process. The chlorophyll, soluble sugar, and amino acid content in the tea leaves was increased. The phytohormones, carbohydrates, and amino acid levels were zoomed-in in both transcript and metabolomics analyses compared to the control. The expression of the genes related to phytohormones transduction, carbon fixation, and amino acid metabolism during the growth and development of tea plants were significantly upregulated. Our findings indicated that alerted transcriptomic and metabolic responses occurring with the application of COS could cause efficiency in substrates in pivotal pathways and hence, elicited plant growth.

Amelioration of imiquimod-induced psoriasis-like dermatitis in mice by DSW therapy inspired hydrogel.

Psoriasis is a long-lasting and recurrent autoimmune disease which is incurable so far. Dead Sea water (DSW) therapy is an effective approach to help control the symptoms of psoriasis due to the abundant mineral ions in DSW, which inspired the material formulation in this study. Rubidium-Sodium alginate/Polyacrylamide hydrogels (Rb-SA/PAAm gels) composed of sodium alginate and polyacrylamide interpenetrating network structure with different concentrations of rubidium and certain magnesium and zinc content were prepared for the treatment of psoriasis. The obtained results suggest the good mechanical properties of the Rb-SA/PAAm gels including toughness and swelling performance. In terms of in vitro tests, the Rb-SA/PAAm gels not only show nontoxicity to human keratinocyte cell line (Hacats) but also inhibits the activity against inflammatory NF-κß signaling pathway. Meanwhile, they can release Rb+ which enable the Rb-SA/PAAm gels have better antibacterial ability to Streptococcus and Escherichia coli. The results obtained from in vivo tests indicate that these hydrogels could alleviate the symptoms of psoriasis caused by Imiquimod (IMQ) in mice by reducing the inflammatory factor in STAT3 pathway and therefore reduce the immune stimulation of the spleen. In conclusion, the 100Rb-SA/PAAm gel has demonstrated great potential to be a topical wettable dressing for psoriasis treatment.

Feasibility of a Behavioral Intervention to Reduce Psychological Distress in Mechanically Ventilated Patients.

Many survivors of acute respiratory failure suffer from mood disorders following discharge from the hospital. We investigated the feasibility of intensivists delivering psychological support based on positive suggestion (PSBPS) to 20 intubated patients to reduce their psychological distress. Thirteen patients completed follow-up surveys. Of those, 9 remembered the intensive care unit physician talking to them, and 7 described it as comforting. Five patients (38%) met criteria for anxiety, depression, and acute stress. In comparison to historical controls, intervention may be associated with lower estimated odds of anxiety. PSBPS can be performed with patients in parallel with medical treatment to potentially reduce psychological morbidity and to humanize critical care. A larger randomized study is warranted to assess the efficacy of PSBPS.

Rubidium-containing mesoporous bioactive glass scaffolds support angiogenesis, osteogenesis and antibacterial activity.

In this study, rubidium-containing mesoporous bioglass (Rb-MBG) scaffolds were formed with the investigation of the influence of Rb addition on angiogenic and osteogenic differentiation abilities of hBMSC. The phase composition, microstructure, pore size distribution, ion release, biological activity, drug loading rate, and release rate of Rb-MBG were characterized. The proliferation and differentiation of hBMSC, the markers of bone formation (ALP, COL-1) and angiogenesis (VEGF, HIF-1α), and wnt/ß-catenin related-signaling pathway gene were studied by cell culture. Rb-MBG loaded with antibacterial agents enoxacin (ENX), coliforms and Staphylococcus aureus were cultured together to study the antibacterial effects. The results indicate that the samples have a 350-550 µm large pore structure and 4.5-5.5 nm mesoporous size. Adding Rb can increase the activity of ALP, the secretion of VEGF and COLI, and the expression of HIF-1α of hBMSCs. Rb containing MBG is likely to enhance the proliferation and differentiation of hBMSCs through the influence of Wnt/ß-catenin signal path. Rb-MBG scaffold can load effectively and release Rb ions and ENX continuously to damage the bacterial cell membrane with the synergistic effect, and therefore achieve antibacterial results. In conclusion, adding Rb to MBG supports angiogenesis and osteogenesis of hBMSCs, as well as antibacterial activity.

Activating macrophages for enhanced osteogenic and bactericidal performance by Cu ion release from micro/nano-topographical coating on a titanium substrate.

In the field of orthopaedics, inflammation-modulatory biomaterials are receiving increasing attentions due to their abilities to regulate innate immune response and mediate wound healing. In the current work, a Cu-containing micro/nano-topographical bio-ceramic surface (Cu-Hier-Ti surface) was employed as material model to explore the role played by Cu2+ release or material surface in regulating macrophage polarization as well as macrophage-mediated osteogenic and bactericidal effect. A Cu-free micro-topographical surface (Micro-Ti surface) generated by micro-arc oxidation was employed as control. The results showed that Cu2+ supplemented directly into the culture medium or released from Cu-Hier-Ti surface could polarize macrophages to pro-inflammatory M1 phenotype by activating Cu-transport signaling (copper transporter 1 (CTR1) and ATP7A) in macrophages, while the material characteristics exhibited anti-inflammatory effect to some extent by regulating integrin (α5, αM, ß1 and ß2) and TLR (TLR-3, TLR-4, Myd88 and Ticam-1/2) signaling. Macrophages grown on Cu-Hier-Ti surface or treated by Cu2+ could create a favorable inflammatory microenvironment for osteoblast-like SaOS-2 cell proliferation and differentiation. Moreover, Cu-Hier-Ti surface promoted macrophage capacity to engulf and kill bacteria, even though it did not show direct bactericidal effect against Staphylococcus aureus. In vivo results showed that Cu-Hier-Ti surface could lead to promoted osteointegraion and enhanced expression levels of M1 surface marker CD11c, growth factor BMP-6 and osteogenic makers including osteocalcin (OCN) and Runx-2 at the biomaterial/bone tissue interface in a rat model. The results indicate that Cu could be employed as a promising inflammation-modulatory agent to activate macrophages for enhanced osteogenic and bactericidal effect. STATEMENT OF SIGNIFICANCE: The next generation of bone biomaterials should be active to regulate the local inflammatory environment such that it favors bone regeneration. For the design and development of Cu-containing inflammation-modulatory biomaterials, it is of great importance to recognize the exact role played by Cu2+ release or material surface characteristics. So far, relatively little is known about the regulatory role of Cu2+ or micro/nano-topographical surface on macrophages. The results in the current work suggest that Cu2+ release and material surface characteristics of Cu-containing micro/nano-topographical coating could activate distinct signaling pathways in macrophages. The activated M1 macrophages exhibited stimulatory effect on osteoblast maturation and enhanced bactericidal capacity against Staphylococcus aureus. This study might provide new thoughts for the development of multi-functional Cu-containing biomaterials.

[ARTICLE WITHDRAWN] Wound Dressings Based on Rubidium-Doped Bioactive Glass Nanospheres Promote Diabetic Wound Healing.

THIS ARTICLE WAS WITHDRAWN BY THE PUBLISHER IN MARCH 2021

Rubidium-doped titanium surfaces with modulatory effects on MC3T3-E1 cell response and antibacterial capacity against Staphylococcus aureus.

To simultaneously impart excellent biological activity and antibacterial function to titanium-based metal materials, rubidium-doped titanium surfaces were prepared via alkali heat treatment, subsequent hydrothermal treatment and final heat treatment. The alkali heat treatment was employed to fabricate an amorphous sodium titanate hydrogel layer on titanium substrates. Thereafter, rubidium was introduced through the hydrothermal process. After final heat treatment, crystallized rubidium titanate and sodium titanate were obtained on titanium surfaces. The viability of MC3T3-E1 cells was inhibited on rubidium-doped titanium surfaces for short-term (day 1). With prolonged duration, the viability and alkali phosphatase (ALP) activity were comparable for various surfaces with different amounts of rubidium (day 5). With further increased culture duration, the collagen synthesis (day 10) and in vitro mineralization of osteoblasts were found to be significantly enhanced on rubidium-doped titanium surfaces. The Rb-doped Ti surfaces showed antibacterial capacity against Staphylococcus aureus at both 12 and 24 h. The results indicate that doping rubidium into titanium surfaces could simultaneously endow materials with favorable osteogenic and antibacterial capacity.

Multifunctional two dimensional Bi2Se3 nanodiscs for combined antibacterial and anti-inflammatory therapy for bacterial infections.

A multifunctional platform based on two-dimensional nanomaterials for combined antibacterial and anti-inflammatory therapy is developed. Bi2Se3 nanodiscs selectively eradicate Gram-positive bacteria with a low risk of drug resistance. Moreover, Bi2Se3 nanodiscs with antioxidant activity relieve intracellular oxidative stress of macrophages to suppress inflammation caused by bacterial infections.