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Chlamydia pneumoniae (C. pneumoniae) is a specialized intracellular parasitic pathogen capable of causing pneumonia, sinusitis, bronchitis, and other respiratory diseases, which pose significant public health challenges. Therefore, rapid, accurate, and sensitive diagnosis is crucial for the prevention and treatment of respiratory diseases caused by C. pneumoniae. In this study, we combined enzymatic recombination amplification (ERA) with the clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR-associated protein (Cas) 12a system (CRISPR/Cas12a) to develop a dual detection platform termed the Cpn-ERA-CRISPR/Cas12a dual system. This system integrates both the ERA-CRISPR/Cas12a fluorescence system and the ERA-CRISPR/Cas12a lateral flow system. Detection results can be measured using a fluorescence detector or observed with the naked eye on lateral flow strips. The fluorescence system and the lateral flow system detect C. pneumoniae in 30 minutes and 15 minutes, respectively. This dual system exhibits no cross-reactivity with the other seven pathogens, demonstrating high specificity, and achieves a sensitivity of 100 copies/µL. Additionally, the Cpn-ERA-CRISPR/Cas12a dual system was employed to analyze 39 clinical samples, comprising 19 positive and 20 negative samples. The detection rate for positive samples was 100%, with no positive results in the negative samples, indicating a high level of concordance with qPCR results. In summary, the Cpn-ERA-CRISPR/Cas12a dual system represents a novel tool for diagnosing C. pneumoniae and holds promising application potential in grassroots community hospitals. [ABSTRACT FROM AUTHOR]

Mycoplasma pneumoniae is a common cause of community-acquired pneumonia in which neutrophils play a critical role. Immune-responsive gene 1 (IRG1), responsible for itaconate production, has emerged as an important regulator of inflammation and infection, but its role during M. pneumoniae infection remains unknown. Here, we reveal that itaconate is an endogenous pro-inflammatory metabolite during M. pneumoniae infection. Irg1 knockout (KO) mice had lower levels of bacterial burden, lactate dehydrogenase (LDH), and pro-inflammatory cytokines compared with wild-type (WT) controls after M. pneumoniae infection. Neutrophils were the major cells producing itaconate during M. pneumoniae infection in mice. Neutrophil counts were positively correlated with itaconate concentrations in bronchoalveolar lavage fluid (BALF) of patients with severe M. pneumoniae pneumonia. Adoptive transfer of Irg1 KO neutrophils, or administration of β-glucan (an inhibitor of Irg1 expression), significantly attenuated M. pneumoniae pneumonia in mice. Mechanistically, itaconate impaired neutrophil bacterial killing and suppressed neutrophil apoptosis via inhibiting mitochondrial ROS. Moreover, M. pneumoniae induced Irg1 expression by activating NF-κB and STAT1 pathways involving TLR2. Our data thus identify Irg1/itaconate pathway as a potential therapeutic target for the treatment of M. pneumoniae pneumonia. Author summary: M. pneumoniae is a common human pathogen that causes community-acquired pneumonia. Neutrophil infiltration has been widely recognized as a characteristic of M. pneumoniae pneumonia; however, the interaction between neutrophils and M. pneumoniae is not completely understood. Here we demonstrate a critical role of the Irg1/itaconate metabolic pathway in neutrophils in the pathogenesis of M. pneumoniae pneumonia. We observe a positive correlation between neutrophil counts and itaconate levels in BALF from patients with severe M. pneumoniae pneumonia. We find that M. pneumoniae infection induces itaconate production in neutrophils, which dampens neutrophil bactericidal activity and impedes neutrophil apoptosis through inhibiting mitochondrial ROS (mtROS). Suppressing neutrophil itaconate production mitigates M. pneumoniae pneumonia in mice. We also find that M. pneumoniae induces Irg1 expression in neutrophils by activating NF-κB and STAT1 signaling pathways. Therefore, our findings suggest that targeting neutrophil itaconate production may be an effective therapeutic strategy for the treatment of M. pneumoniae pneumonia in humans. [ABSTRACT FROM AUTHOR]

The electrocatalytic carbon dioxide reduction reaction is an effective means of combating the greenhouse effect caused by massive carbon dioxide emissions. Carbon nitride in the graphitic phase (g-C3N4) has excellent chemical stability and unique structural properties that allow it to be widely used in energy and materials fields. However, due to its relatively low electrical conductivity, to date, little effort has been made to summarize the application of g-C3N4 in the electrocatalytic reduction of CO2. This review focuses on the synthesis and functionalization of g-C3N4 and the recent advances of its application as a catalyst and a catalyst support in the electrocatalytic reduction of CO2. The modification of g-C3N4-based catalysts for enhanced CO2 reduction is critically reviewed. In addition, opportunities for future research on g-C3N4-based catalysts for electrocatalytic CO2 reduction are discussed. [ABSTRACT FROM AUTHOR]

Herein, a novel approach used to enhance the conversion of electrochemical CO2 reduction (CO2R), as well as the capacity to produce C2 products, is reported. A copper oxide catalyst supported by graphite phase carbon nitride (CuO/g-C3N4) was prepared using a one-step hydrothermal method and exhibited a better performance than pure copper oxide nanosheets (CuO NSs) and spherical copper oxide particles (CuO SPs). The Faradaic efficiency reached 64.7% for all the C2 products, specifically 37.0% for C2H4, with a good durability at −1.0 V vs. RHE. The results suggest that the interaction between CuO and the two-dimensional g-C3N4 planes promoted CO2 adsorption, its activation and C-C coupling. This work offers a practical method that can be used to enhance the activity of electrochemical CO2R and the selectivity of C2 products through synergistic effects. [ABSTRACT FROM AUTHOR]

Objective: To study the pharmacokinetics and bioequivalence of asparaginase loaded in hyaluronic acid-graft-poly(ethylene glycol)/ sulfobutylether-β-cyclodextrin nanocapsules (AHSP) in SD rats., Methods: The morphology of AHSP was observed under the transmission electron microscope and the particle size and zeta potential were measured. AHSP and free asparaginase were intravenously injected in rats, and the plasma asparaginase activity was measured at different time points after the injections. The pharmacokinetic parameters were calculated using the software DAS 2.1.1 to assess the bioequivalence of AHSP and free asparaginase., Results: AHSP had an average particle size of 413.80∓10.97 nm with a zeta potential of -20.37∓2.38 mV. The AUC(0-48 h) of AHSP and free asparaginase was 137.34∓1.82 U/mL and 46.38 ∓1.98 U/mL, and their AUC(0-∞) was 164.66∓6.88 U/mL and 51.44∓3.01 U/mL with half-lives of 4.62∓0.60 h and 1.86∓0.38 h, respectively. Compared with free AN, AHSP exhibited increased AUC(0-48 h), AUC(0-∞), and half-life by 2.24, 2.55 and 2.32 folds, respectively. The 90% confidential intervals of AUC(0-48 h), AUC(0-∞) and Cmax of the tested formulation were 75.0%-76.5%, 74.3%-76.1%, and 95.1%-96.7%, respectively., Conclusion: AHSP can improve the bioavailability and extend the biological half-life of asparaginase in rats, and AHSP and free asparaginase are not bioequivalent.

Objective: To characterize the property of uricase loaded in uricase-catalase liposomes (BUCLPs) prepared using borate buffer., Methods: BUCLPs were prepared using reverse-phase evaporation, and the physicochemical properties of uricase in the prepared BUCLPs were examined., Results: The optimal temperature of BUCLP and URI was 40 degrees celsius, their optimal pH values were 8.0 and 8.5, and their Michaelis-Menten constants were 14.207 µmol/L and 13.623 µmol/L, respectively. Fluorescence intensity of nanoliposome-loaded uricase-catalase that bound to FITC was higher than that of uricase-catalase binding directly with FITC; the fluorescence intensity of BUCLP was higher than that of free uricase-catalase at 280 nm., Conclusion: Uricase activity is enhanced after loading in uricase and catalase liposomes.

The molecular imprinted polymer (MIP) with high selectivity to di(2-propylheptyl) phthalate (DPHP) was synthesized by precipitation polymerization with dioctyl phthalate (DOP) as dummy template, methacrylic acid (MAA) as functional monomer and ethylene glycol dimethacrylate (EDMA) as cross-linker. The binding ability of the template and functional monomer was investigated by UV spectrometry. Compared with the functional monomer acrylic acid (AA), MAA showed stronger binding capacity to DOP and the best combination mole ratio of 6 : 1. The selective adsorption performance of MIP for DOP, DPHP, dimethyl phthalate (DMP) and dibutyl phthalate (DBP) was investigated using the prepared MIP as high performance liquid chromatographic column packing. It was found that the prepared MIP showed higher retention ability and selectivity for DPHP. Using the prepared MIP as a solid-phase extraction (SPE) sorbent (MISPE), the effects of the type and amount of washing solvent and elution solvents on the recovery of DPHP were investigated. After optimization of MISPE profile, the DPHP extraction recovery of 96.8% was obtained when the following procedures were applied to MISPE cartridge: conditioning with 2 mL methanol, loading with 1 mL methanol, washing with 1 mL methanol-water (1 : 9, v/v), eluting with 5 mL methanol-acetic acid (9:1, v/v). The recovery of DPHP on non-imprinted polymer (NIP) cartridge was only 52.9%. The developed MISPE-HPLC method was applied to determine the concentrations of DPHP in rabbit serum at different time points after oral administration. It was found that the maximal concentration (c(max)) and time (t(max)) were 5.88 microg/mL and 4 h, respectively. The recoveries of spiked DPHP in rabbit serum ranged from 90.0% to 92.0% with the relative standard deviations less than 5%.