Porphyrin production by the haemin-independent Haemophilus parainfluenzae in the diagnostic porphyrin test, which determines the X-factor requirement in Haemophilus spp., was analysed quantitatively by applying modern high-performance liquid chromatographic (HPLC) methods. Ion-pair reversed-phase HPLC enabled the simultaneous separation of all porphyrin intermediates and their isomers of haem biosynthesis produced by the bacteria. The pH-dependence of porphyrin production and the respective composition of the porphyrins within the bacterial cells and in the supernate were investigated. A pH optimum of 6.9-8.0 for the production of porphyrins was found and there were marked differences in the porphyrin profiles at different pH values.
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http://dx.doi.org/10.1099/00222615-39-4-262 | DOI Listing |
J Colloid Interface Sci
January 2025
The Department of Medical Imaging, Guangzhou Key Laboratory of Molecular Functional Imaging and Artificial Intelligence for Major Brain Diseases, The Affiliated Guangdong Second Provincial General Hospital of Jinan University, Jinan University, Guangzhou 518037 China. Electronic address:
Microwave dynamic therapy (MWDT) destroy tumor cells using reactive oxygen species (ROS), but its effectiveness is limited by low ROS production and intracellular oxygen (O) availability. This study presents a novel strategy using manganese (II) ion (Mn) doped iron (Fe)-based metal-organic framework (Fe MOF) nanoparticles (NPs) to enhance both O generation and ROS production for improved MWDT. Incorporating Mn into Fe MOF narrows the bandgap from 0.
View Article and Find Full Text PDFBiomater Sci
January 2025
Zhejiang Key Laboratory of Smart BioMaterials, and College of Chemical and Biological Engineering, Zhejiang University, Hangzhou 310058, China.
Accurate imaging of tumor hypoxia is critical for early cancer diagnosis and clinical outcomes, highlighting the great need for its detection specificity and sensitivity. In this report, we propose a probe (HTRNP) that simultaneously has hypoxia-targeting and hypoxia-responsive capabilities to enhance the tumor hypoxia imaging efficiency. HTRNP was successfully prepared through the encapsulation of Pt(II)-tetrakis(pentafluorophenyl)porphyrin (PtPFPP), which exhibits hypoxia-dependent phosphorescence, within the amphiphilic block copolymer OPDMA-PF, which has hypoxia-targeting tertiary amine -oxide moieties and hydrophobic perfluorobenzene ring structures, which highly improved the loading content and water solubility of PtPFPP.
View Article and Find Full Text PDFNanoscale
January 2025
Institute of Hepatobiliary and Pancreatic Surgery, Department of Hepatobiliary and Pancreatic Surgery, Shanghai East Hospital, School of Medicine, Tongji University, Shanghai, 200120, P. R. China.
The mode of energy transfer between photosensitizers and oxygen determines the yield of singlet oxygen (O), crucial for photodynamic therapy (PDT). However, the aggregation of photosensitizers promotes electron transfer while inhibiting pure energy transfer, resulting in the generation of the hypotoxic superoxide anion (O) and consumption of substantial oxygen. Herein, we achieve the reduction of the aggregation of photosensitizers to inhibit electron transfer through classical chemical crosslinking, thereby boosting the production of O.
View Article and Find Full Text PDFJ Med Virol
February 2025
Department of Chemistry, Assam University, Silchar, India.
The biological applications of noncationic porphyrin-fullerene (P-F) dyads as anti-HIV agents have been limited despite the established use of several cationic P-F dyads as anti-cancer photodynamic therapy (PDT) agents. This article explores the potential of amphiphilic non-cationic porphyrin-fullerene dyads as HIV-1 inhibitors under both PDT (light-treated) and non-PDT (dark) conditions. The amphiphilic P-F dyads, PBC and PBC, demonstrated enhanced efficacy in inhibiting the entry and production of HIV-1 (subtypes B and C).
View Article and Find Full Text PDFJ Med Chem
January 2025
Department of Chemistry, Tianjin University, Tianjin 300072, China.
The integration of photodynamic therapy (PDT) and photothermal therapy (PTT) offers a promising strategy for enhancing phototherapy efficiency. Herein, we present a dual-functional, biocompatible nanocomposite system for combination PDT/PTT therapy. The system utilizes a highly biocompatible nanoparticle assembled by an amphiphilic short peptide with the assistance of Zn as a carrier.
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