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We investigated the role of mitochondrial reactive oxygen species (ROS) in the response of macrophages to lipopolysaccharide (LPS) using RAW 264.7 cells and their ρ(o) cells lacking mitochondria. Mitochondrial density, respiratory activity and related proteins in ρ(o) cells were significantly lower than those in RAW cells. LPS rapidly stimulated mitochondrial ROS prior to cytokine secretion, such as TNF-α and IL-6, from RAW 264.7 cells by activating the MAPK pathway, while the response was attenuated in ρ(o) cells. Exposure of ρ(o) cells to H(2)O(2) partially restored the secretion of cytokines induced by LPS. These results suggest that mitochondrial density and/or the respiratory state contribute to intracellular oxidative stress, which is responsible for the stimulation of LPS-induced MAPK signaling to enhance cytokine release from macrophages.
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http://dx.doi.org/10.1016/j.febslet.2011.05.049 | DOI Listing |
Cancer Med
August 2025
Human Biology Division, Fred Hutchinson Cancer Center, Seattle, Washington, USA.
Objective: To illustrate a new barcoded orthotopic patient-derived xenograft (PDX) mouse model where one can investigate phenotypic effects of single-cell level gene manipulation in a pooled format. To address some concerns of current PDX mouse models of head and neck squamous cell carcinoma (HNSCC): (1) genomic evolution with passage by generating high-purity cancer cells, which can also be utilized for other downstream applications, including cell culture-based studies, and (2) cost-effectiveness of current PDX models.
Methods: Two-millimeter tumor cubes from nine patients were implanted into immunodeficient mouse flanks subcutaneously.
Cells
July 2025
Maryland Psychiatric Research Center, Department of Psychiatry, University of Maryland School of Medicine, Baltimore, MD 21228, USA.
The enzymatic formation of kynurenic acid (KYNA), a neuromodulator metabolite of the kynurenine pathway (KP) of tryptophan metabolism, in the mammalian brain is widely attributed to kynurenine aminotransferase II (KATII). However, an alternative biosynthetic route, involving the conversion of D-kynurenine (D-KYN) to KYNA by D-amino acid oxidase (D-AAO), may play a role as well. In the present study, we first confirmed that purified D-AAO efficiently converted D-KYN-but not L-KYN-to KYNA.
View Article and Find Full Text PDFACS Sens
July 2025
Engineering Research Center of Nano-Geomaterials of Ministry of Education, Faculty of Materials Science and Chemistry, China University of Geosciences, Wuhan430074, P. R. China.
Tailoring the surface charge has emerged as a promising method for developing target-responsive iontronic sensors. However, the single anionic effect cannot satisfy the needs of highly sensitive iontronic sensing for the detection of low-abundance microRNAs (miRNAs). Here, the synergistic interplay between hydrophobicity and negative charge on the nanopore surface was proposed for the dual-amplified iontronic detection of miRNA-34a.
View Article and Find Full Text PDFWater Res
September 2025
Single-Cell Center, CAS Key Laboratory of Biofuels, Shandong Key Laboratory of Energy Genetics and Shandong Energy Institute, Qingdao Institute of BioEnergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao, Shandong, PR China; University of Chinese Academy of Sciences, Beijing, PR Chi
Rational engineering of ecosystems is often hindered by the inability to rapidly identify, profile, culture and apply the microbes that underlie target metabolic activity in situ. Here, we developed an In-situ Metabolism driven Sorting, Culture and Augmentation (IMSCA) strategy via Raman-activated Cell Sorting coupled to single-cell culture (scRACS-Culture), and demonstrated it through the mining of in situ polyphosphate-accumulating organisms (PAOs) for wastewater treatment. Single-cell polyphosphate-accumulating activities in situ were quantitatively assessed directly from environmental samples via the polyphosphate band in Raman spectrum, revealing their remarkable distinction from those from pure cultures.
View Article and Find Full Text PDFMethods Enzymol
June 2025
Centro de Investigaciones Biológicas Margarita Salas (CIB), Consejo Superior de Investigaciones Científicas (CSIC), Madrid, Spain. Electronic address:
Aryl-alcohol oxidase (AAO) is an FAD-dependent enzyme belonging to the glucose-methanol-choline oxidoreductase superfamily. AAOs are secreted by fungi and play a fundamental role as auxiliary enzymes in the lignocellulolytic process. On the one hand, they produce HO that activates peroxidases, which directly oxidize lignin, and triggers Fenton reactions to produce reactive oxygen species that attack lignin and carbohydrates.
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