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Objective To investigate the role of macrophages in the process of fine particulate matter (PM2.5) exposure induced damage to pulmonary blood-air barrier. Methods Eighteen male BALB/C mice (aged of 10 weeks, weighing 24~27 g) were randomly divided into control group and low- and high-dose PM2.5 exposure groups (receiving 1.8 and 16.2 mg/kg, respectively), with 6 mice in each group. The control group received tracheal instillations of normal saline on days 1, 4, and 7, whereas the exposure groups were administered corresponding dose of PM2.5 exposure at the same time points. In 24 h after last exposure, pathological changes in the lung tissues were observed, and the contents of total protein (TP), lactate dehydrogenase (LDH), and alkaline phosphatase (AKP) in bronchoalveolar lavage fluid (BALF), and F4/80 protein level in lung tissue were measured to evaluate the blood-air barrier damage and macrophage infiltration within the lung tissues. Additionally, an in vitro model of the blood-air barrier was established using A549 alveolar epithelial cells and EA.hy926 vascular endothelial cells. In combination with a THP-1 macrophage model, the supernatant PM2.5 supernatant, macrophage supernatant, and PM2.5-macrophage supernatant were incubated with the barrier model for 24 h, respectively. Transmembrane electrical resistance (TEER), sodium fluorescein permeability of the barrier model, and LDH release from the barrier cells were measured to ascertain the extent of macrophage-mediated enhancement in barrier damage induced by PM2.5 exposure. Furthermore, the expression of inflammatory cytokines, such as TNF-α, IL-1β, IL-6, and IL-8 in the macrophages after PM2.5 exposure was analyzed with quantitative real-time PCR (qPCR) and enzyme-linked immunosorbent assay (ELISA). Results PM2.5 exposure induced lung tissue damage in mice in a dose-dependent manner, significantly elevated the contents of TP, LDH and AKP in the BALF and caused marked infiltration of macrophages into the lung tissue, especially the high-dose exposure when compared with the mice from the control group (P

Patients who suffer from sepsis typically experience acute lung injury (ALI). Extracellular vesicles (EVs) contain miRNAs, which are potentially involved in ALI. However, strategies to screen more effective EV-miRNAs as therapeutic targets are yet to be elucidated. In this study, functional EV-miRNAs were identified based on multiomics analysis of single-cell RNA sequencing of targeted organs and serum EV (sEV) miRNA profiles in patients with sepsis. The proportions of neutrophils and macrophages were increased significantly in the lungs of mice receiving sEVs from patients with sepsis compared with healthy controls. Macrophages released more EVs than neutrophils. MiR-125a-5p delivery by sEVs to lung macrophages inhibited Tnfaip3, while miR-221-3p delivery to lung neutrophils inhibited Fos. Macrophage membrane nanoparticles (MM NPs) loaded with an miR-125a-5p inhibitor or miR-221-3p mimic attenuated the response to lipopolysaccharide (LPS)-induced ALI. Transcriptome profiling revealed that EVs derived from LPS-stimulated bone marrow-derived macrophages (BMDMs) induced oxidative stress in neutrophils. Blocking toll-like receptor, CXCR2, or TNFα signaling in neutrophils attenuated the oxidative stress induced by LPS-stimulated BMDM-EVs. This study presents a novel method to screen functional EV-miRNAs and highlights the pivotal role of macrophage-derived EVs in ALI. MM NPs, as delivery systems of key sEV-miRNA mimics or inhibitors, alleviated cellular responses observed in sepsis-induced ALI. This strategy can be used to reduce septic organ damage, particularly lung damage, by targeting EVs. [ABSTRACT FROM AUTHOR]

To investigate the optimal delivery system of quercetin, in this paper, cellulose nanocrystals (CNCs) extracted from rice bran were used to stabilize the Pickering emulsion and Pickering emulsion gels (PEGs) with quercetin. To compare the emulsion properties, stability, antioxidation activity, encapsulation rate, and bioaccessibility of the quercetin, four emulsions of CNC Pickering emulsion (C), CNC Pickering emulsion with quercetin (CQ), CNC Pickering gel emulsion (CG), and CNC Pickering gel emulsions with quercetin (CQG) were prepared. All four emulsions exhibited elastic gel network structure and good stability. The quercetin significantly reduced the particle size, increased the stability, and improved the antioxidant capacity of CQ and CQG. Compared to C and CG, the ABTS+ radical scavenging capacities of CQ and CQG were respectively enhanced by 46.92% and 3.59%. In addition, CQG had a higher encapsulation rate at 94.57% and higher bioaccessibility (16.17) compared to CQ. This study not only indicated that CNC from rice bran could be exploited as an excellent stabilization particle for Pickering emulsions, but also provided a highly stable and bioaccessible delivery system for water-insoluble functional active factors. [ABSTRACT FROM AUTHOR]

The high-resolution array is the basic structure of most kinds of microelectronics. Electrohydrodynamic jet (E-Jet) printing technology is widely applied in manufacturing array structures with high resolution, high material compatibility and multi-modal printing. It is still challenging to acquire high uniformity of printed array with micro-nanometer resolution, which greatly influences the performance and lifetime of the microelectronics. In this paper, to improve the uniformity of the printed array, the influence of each parameter on the uniformity of the E-jet printed dot array is studied on the cobuilt NEJ-E/P200 experimental platform, finding the applied voltage plays the most important role in maintaining the uniformity of the printed array. By appropriately adjusting the printing parameters, the dot arrays with different resolutions from 500 pixels per inch (PPI) to 17,000 PPI are successfully printed. For arrays below and over 10,000 PPI, the deviations of the uniformity are within 5% and 10% respectively. In this work, the dot array over 15,000 PPI is first implemented using E-jet printing. The conclusions acquired by experimental analysis of dot array printing process are of great importance in high resolution array printing as it provides practical guidance for parameters adjustment., (© 2024. The Author(s).)

Objective: This study aims to analyze the composition and distribution of pathogenic bacteria in lower respiratory tract infections (LRTI) and their antimicrobial resistance patterns in a hospital in Xinjiang, to guide more effective antibiotic selection and inform clinical management., Methods: We retrospectively analyzed 545 strains isolated from various clinical specimens like sputum and blood, collected between June 2020 and June 2023, using the LIST system. The strains were subjected to drug resistance testing, and statistical analyses included t tests and Chi-square tests., Results: Among gram-negative bacilli, Acinetobacter baumannii dominated, accounting for 32.11%, followed by Pseudomonas aeruginosa, accounting for 18.35%. Among gram-positive bacteria, thrombin-negative staphylococcus was at the top of the list, followed by Staphylococcus aureus. Among Acinetobacter baumannii (AB), carbapenem-resistant Acinetobacter baumannii plays a dominant role. The sensitivity rate of these strains to tigecycline and amikacin could reach more than 80%. The sensitivity of Pseudomonas aeruginosa (PA) to piperacillin, gentamicin, imipenem, meropenem, ciprofloxacin and levofloxacin ranged from 50% to 80%. It is worth mentioning that the sensitivity rate of PA to amikacin, cefoperazone, and tobramycin exceeded 80%. Amikacin was more than 60% sensitive to carbapenem, β-lactam inhibitors, tigecycline, quinolones, and aminoglycosides of ESBL producing Klebsiella pneumoniae. Among gram-positive coccus, methicillin-resistant coagulase-negative staphylococcus was 100% sensitive to duration, e, tigecycline, and vancomycin. In addition, the susceptibility rate of these strains to rifampicin and linezolid was greater than 70%., Conclusions: In patients with lower respiratory tract infection (LRTI) in a hospital in Xinjiang, the most common pathogenic bacteria are gram-negative bacilli, mainly Acinetobacter baumannii and Pseudomonas aeruginosa. Both resistant and non-resistant strains showed sensitivity to amikacin and tigecycline. Additionally, staphylococcus accounted for half of the total number of gram-positive bacteria, among which methicillin-resistant strains were more sensitive to vancomycin and linezolid.