3D Printed Multifunctional Biomimetic Bone Scaffold Combined with TP-Mg Nanoparticles for the Infectious Bone Defects Repair.

Infected bone defects are one of the most challenging problems in the treatment of bone defects due to the high antibiotic failure rate and the lack of ideal bone grafts. In this paper, inspired by clinical bone cement filling treatment, α-c phosphate (α-TCP) with self-curing properties is composited with ß-tricalcium phosphate (ß-TCP) and constructed a bionic cancellous bone scaffolding system α/ß-tricalcium phosphate (α/ß-TCP) by low-temperature 3D printing, and gelatin is preserved inside the scaffolds as an organic phase, and later loaded with a metal-polyphenol network structure of tea polyphenol-magnesium (TP-Mg) nanoparticles. The scaffolds mimic the structure and components of cancellous bone with high mechanical strength (>100 MPa) based on α-TCP self-curing properties through low-temperature 3D printing. Meanwhile, the scaffolds loaded with TP-Mg exhibit significant inhibition of Staphylococcus aureus (S.aureus) and promote the transition of macrophages from M1 pro-inflammatory to M2 anti-inflammatory phenotype. In addition, the composite scaffold also exhibits excellent bone-enhancing effects based on the synergistic effect of Mg2+ and Ca2+. In this study, a multifunctional ceramic scaffold (α/ß-TCP@TP-Mg) that integrates anti-inflammatory, antibacterial, and osteoinduction is constructed, which promotes late bone regenerative healing while modulating the early microenvironment of infected bone defects, has a promising application in the treatment of infected bone defects.

Brownification increases the abundance of microorganisms related to carbon and nitrogen cycling in shallow lakes.

Brownification in aquatic ecosystems under global change has attracted attention. The composition and quantity of dissolved organic matter transported from various land use types to lakes differ significantly, causing varying ecological effects of lake brownification by region. Bacterial communities make a significant contribution to the material cycle of ecosystems and are sensitive to environmental changes. In this study, a series of mesocosm systems were used to simulate forest lakes and urban lakes with different degrees of brownification, and a high-throughput amplicon sequencing technique was used to explore the changes in the composition, structure, and function of bacterial communities in shallow lakes undergoing brownification. Principal coordinate analysis (PCoA) and Jensen‒Shannon distance typing analysis both indicated significant differences in bacterial communities between forest lakes and urban lakes. The α diversity of bacterial communities in urban lakes increased with the degree of brownification. However, whether forest lakes or urban lakes, brownification increased the abundance of carbon cycling-related bacterial phyla (Proteobacteria, Poribacteria, and Chloroflexi) and nitrogen cycling-related bacterial genera (Microbacteriaceae, Limnohabitans, Comamonadaceae, Bacillus, and Rhizobiales_Incertae_Sedis). Additionally, the carbon and nitrogen cycling functions of bacterial communities in forest lakes are dominant, while those in urban lakes are dominated by functions related to light. Our study has preliminarily revealed that lake brownification promotes the growth of carbon and nitrogen cycling microorganisms, providing a new paradigm for understanding the response of lake ecosystems in different catchment areas to environmental changes and the carbon and nitrogen cycling processes in shallow lake ecosystems.

Optimization of operating parameters and microbiological mechanism of a low C/N wastewater treatment system dominated by iron-dependent autotrophic denitrification.

Ferrous iron (Fe2+) reduces the amount of external carbon source used for the denitrification of low-C/N wastewater. The effects of key operating parameters on the efficiency of ferrous-dependent autotrophic denitrification (FDAD) and the functioning mechanism of the microbiome can provide a regulatory strategy for improving the denitrification efficiency of low C/N wastewater. In this study, the response surface method (RSM) was used to explore the influence of four important parameters-the molar ratio of Fe2+ to NO3--N (Fe/N), total organic carbon (TOC), the molar ratio of inorganic carbon to NO3--N (IC/N) and sludge volume (SV, %)-on the FDAD efficiency. Functional prediction and molecular ecological networks based on high-throughputs sequencing techniques were used to explore changes in the structure, function, and biomarkers of the sludge microbial community. The results showed that Fe/N and TOC were the main parameters affecting FDAD efficiency. Higher concentrations of TOC and high Fe/N ratios provided more electron donors and improved denitrification efficiency, but weakened the importance of biomarkers (Rhodanobacter, Thermomonas, Comamonas, Thauera, Geothrix and unclassified genus of family Gallionellaceae) in the sludge ecological network. When Fe/N > 4, the denitrification efficiency fluctuated significantly. Functional prediction results indicated that genes that dominated N2O and NO reduction and the genes that dominated Fe2+ transport showed a slight decrease in abundance at high Fe/N levels. In light of these findings, we recommend the following optimization ranges of parameters: Fe/N (3.5-4); TOC/N (0.36-0.42); IC/N (3.5-4); and SV (approximately 35%).

Efficacy and safety of glucagon-like peptide-1 receptor agonists in the elderly versus non-elderly patients with type 2 diabetes mellitus: insights from a systematic review.

This systematic review aimed to compare the influence of glucagon-like peptide-1 receptor agonists (GLP-1RAs) on the efficacy and safety of elderly patients with type 2 diabetes and younger individuals. A comprehensive search of PubMed, Embase, and Web of Science databases was conducted up to September 2022. The summary standard means difference and odds ratios were calculated. Thirteen articles were included in the analysis. The incidence of adverse events (AEs) leading to discontinuation was higher in elderly patients (OR = 0.67, 95% CI 0.47 to 0.96, p = 0.028). However, no significant differences were observed in weight loss (SMD = 0.03, 95% CI -0.12 to 0.19, p = 0.686), HbA1c% (SMD = -0.02, 95% CI -0.11 to 0.08, p = 0.715), FBG levels (SMD = -0.03, 95% CI -0.11 to 0.06, p = 0.537), and the incidence of overall AEs (OR = 0.85, 95% CI 0.71 to 1.01, p = 0.072), serious AEs (OR = 0.68, 95% CI 0.45 to 1.04, p = 0.077), nausea (OR = 0.91, 95% CI 0.81 to 1.03, p = 0.140), vomiting (OR = 0.95, 95% CI 0.79 to 1.13, p = 0.532), diarrhea (OR = 0.86, 95% CI 0.72 to 1.02, p = 0.081), and hypoglycemia (OR = 1.22, 95% CI 0.90 to 1.65, p = 0.193). In conclusion, while certain AEs leading to discontinuation may be more prevalent in older patients, GLP-1RAs are effective for weight loss and lead to decreased glucose concentrations with a low rate of complications in elderly patients.

Family members' experiences of bereavement in the emergency department: A meta-synthesis of qualitative studies.

The emergency department (ED) is one of the places where patient deaths frequently occur. Understanding family members' experiences of bereavement would help provide individualized bereavement care. We conducted a meta-synthesis to synthesize family members' experiences of bereavement in the ED and assess the impact of bereavement on their lives. We searched seven international electronic databases. Five studies were selected and critically appraised. Thematic analysis was employed. Five themes (with 13 subthemes) were derived: suffering sudden changes and are severely impacted, multiple feelings and needs of waiting, final farewell, personal and family difficulties after leaving the ED, and journey through grief. Family members endured agonizing waits to see and learn more about their family members' condition. Family members reported the need for effective follow-up resources. Findings revealed that it would be helpful if the EDs could provide sensitive and respectful care to family members.

Nitrifiers Cooperate to Produce Nitrous Oxide in Plateau Wetland Sediments.

The thawing of dormant plateau permafrost emits nitrous oxide (N2O) through wetlands; however, the N2O production mechanism in plateau wetlands is still unclear. Here, we used the 15N-18O double tracer technique and metagenomic sequencing to analyze the N2O production mechanism in the Yunnan-Kweichow and Qinghai-Tibet plateau wetlands during the summer of 2020. N2O production activity was detected in all 16 sediment samples (elevation 1020-4601 m: 2.55 ± 0.42-26.38 ± 3.25 ng N g-1 d-1) and was promoted by nitrifier denitrification (ND). The key functional genes of ND (amoA, hao, and nirK) belonged to complete ammonia oxidizing (comammox) bacteria, and the key ND species was the comammox bacterium Nitrospira nitrificans. We found that the comammox bacterial species N. nitrificans and the ammonia oxidizing bacterial (AOB) species Nitrosomonas europaea cooperate to produce N2O in the plateau wetland sediments. Furthermore, we inferred that environmental factors (elevation and total organic matter (TOM)) influence the cooperation pattern via N. nitrificans, thus affecting the N2O production activity in the plateau wetland sediments. Our findings advance the mechanistic understanding of nitrifiers in biogeochemical cycles and global climate change.

Abundance, community and driving factor of nitrifiers in western China plateau.

Complete ammonia oxidation (comammox) is one of the most important biogeochemical processes, with recent studies showing that comammox process dominates nitrification in many ecosystems. However, the abundance, community and driving factor of comammox bacteria and other nitrifying microorganisms in plateau wetland is still unclear. Here, the abundances and community features of comammox bacteria, ammonia-oxidizing archaea (AOA) and ammonia-oxidizing bacteria (AOB) in the wetland sediments of western China plateaus were examined using qPCR and high-throughput sequencing. The results indicate that comammox bacteria were more abundant than AOA and AOB, and dominated the nitrification process. Compared with low-elevation samples (below 3000 m: samples 6-10, 12, 13, 15, 16), the abundance of comammox bacteria was much higher at high-elevation samples (above 3000 m: samples 1-5, 11, 14, 17, 18). The key species of AOA, AOB, and comammox bacteria were Nitrososphaera viennensis, Nitrosomonas europaea, and Nitrospira nitrificans, respectively. The key factor affecting comammox bacteria community was elevation. Elevation could increase the interaction links of key species Nitrospira nitrificans, resulting in high comammox bacterial abundance. The results of this study advance our knowledge of comammox bacteria in natural ecosystems.

The Current Status of Bereavement Care in Chinese Emergency Departments: A Multicenter Cross-Sectional Study.

Understanding the current status and challenges of bereavement care will help facilitate the development of bereavement care in the emergency department. However, little is known about the status of bereavement care in Chinese emergency departments and nurses' perceptions of bereavement care. We used a self-made questionnaire to survey 124 head nurses and 870 emergency nurses in 21 hospitals in Jiangsu Province in September 2023. Among 124 emergency departments, 78 (62.90%) emergency departments provided bereavement care strategies, and the most frequent strategy was a waiting room, relevant information on funeral arrangements and the establishment of a relatively secluded environment conducive to the solace of the patient's family, or the provision of a dedicated farewell chamber. Emergency nurses believed that bereavement care is important but difficult to implement, with support resources, environment and human resources being the main challenges. In the future, further attention should be paid to the development of bereavement care in the emergency department, and the implementation of bereavement care should be supported in terms of policies, funds, resources and personnel.

Isolated Electron-Rich Ruthenium Atoms in Intermetallic Compounds for Boosting Electrochemical Nitric Oxide Reduction to Ammonia.

The direct electrochemical nitric oxide reduction reaction (NORR) is an attractive technique for converting NO into NH3 with low power consumption under ambient conditions. Optimizing the electronic structure of the active sites can greatly improve the performance of electrocatalysts. Herein, we prepare body-centered cubic RuGa intermetallic compounds (i.e., bcc RuGa IMCs) via a substrate-anchored thermal annealing method. The electrocatalyst exhibits a remarkable NH4 + yield rate of 320.6 µmol h-1 mg-1 Ru with the corresponding Faradaic efficiency of 72.3 % at very low potential of -0.2 V vs. reversible hydrogen electrode (RHE) in neutral media. Theoretical calculations reveal that the electron-rich Ru atoms in bcc RuGa IMCs facilitate the adsorption and activation of *HNO intermediate. Hence, the energy barrier of the potential-determining step in NORR could be greatly reduced.

Genomic characterization of two nickie-like bacteriophages that infect the kiwifruit canker phytopathogen Pseudomonas syringae pv. actinidiae.

Here, we report the genomic characterization of two siphophages, named hairong and ZY21, that infect the kiwifruit canker phytopathogen Pseudomonas syringae pv. actinidiae. The genome sequences of hairong (112,842 bp) and ZY21 (112,006 bp) were determined. Global sequence comparison showed that hairong, ZY21, and two phages of the genus Nickievirus (nickie and psageB1) are similar but are not closely related to any other known phage, and they comprise a unique phylogenetic cluster. Moreover, hairong represents a new genus related to Nickievirus. Comparative genomic analysis revealed some common features shared by the four nickie-like phages.