Currently, limited tumor drug permeation and poor oxygen perfusion are two major bottlenecks that significantly impair the efficacy of existing antitumor drugs, especially oxygen‐sensitive antitumor drugs. One vital cause of these major bottlenecks is the abnormal tumor vessel barrier. To the best knowledge of the authors, platelets play a vital role in the maintenance of an abnormal tumor blood barrier through platelet–tumor interaction. Thus, platelet inhibition may present a new way to enhance drug delivery. In this study, it is originally discovered that perfluorotributylamine‐based albumin nanoparticles (PFTBA@HSA) possess excellent platelet inhibiting abilities, which then selectively disrupt the tumor vessel barrier, resulting in a remarkably enhanced intratumoral drug accumulation. Interestingly enough, the tumor hypoxia is also obviously relieved by enhanced oxygen carrier red blood cell distribution and PFTBA@HSA infiltration in the tumors. Finally, the efficacy of oxygen‐sensitive antitumor drugs is significantly amplified by PFTBA@HSA owing to enhanced drug permeation and relieved tumor hypoxia. Therefore, for the first time, it is demonstrated that PFTBA@HSA could be used as an effective way to improve the efficacy of existing tumor therapies by disrupting tumor vessel barriers through targeted platelet inhibition.
Pseudoalteromonas flavipulchra JG1 produces a protein PfaP and a range of small-molecule compounds with inhibitory activities against Vibrio anguillarum. The PfaP protein was purified from the extracellular products of JG1 by electroelution, and antibacterial activity was observed by an in-gel antibacterial assay. The complete amino acid sequence (694 aa) of PfaP was determined by de novo peptide sequencing and subsequent alignment with the proteome sequence of strain JG1. The calculated molecular mass of PfaP was 77.0 kDa. PfaP was 58 % identical to L-lysine oxidase AlpP of Pseudoalteromonas tunicata D2, and 54 % identical to the marinocine antimicrobial protein of Marinomonas mediterranea MMB-1. Five small molecules (compounds 1-5) with antibacterial activity, which were identified as p-hydroxybenzoic acid (1), trans-cinnamic acid (2), 6-bromoindolyl-3-acetic acid (3), N-hydroxybenzoisoxazolone (4) and 29-deoxyadenosine (5), were purified by sequential column chromatography over silica gel, Sephadex LH-20 and RP-18 from ethyl acetate extract of strain JG1, and their structures were determined by NMR and MS. Brown compound 3, the only brominated compound, showed antibacterial activity against both Gram-positive and Gram-negative bacteria.
Vibrio harveyi hemolysin, an important virulence determinant in fish pathogenesis, was further characterized, and the enzyme was identified as a phospholipase B by gas chromatography. Site-directed mutagenesis revealed that a specific residue, Ser153, was critical for its enzymatic activity and for its virulence in fish.
A marine antagonistic bacterium, JG1, was isolated from rearing water of healthy turbot (Scophthalmus maximus) in Qingdao, China. Strain JG1 was Gramnegative, straight rod and motile by polar £agella. The colony, when cultured for 24 h under room temperature, produced a yellow pigment. On the basis of morphological, physiological and biochemical characteristics, along with 16S rDNA sequence analysis, JG1 was identi¢ed as Pseudoalteromonas £avipulchra. JG1 had good inhibitory e¡ects on several bacterial pathogens of aquaculture in the genusVibrio (V. anguillarum, V. alginolyticus,V. campbellii, V. harveyi,V. mimicus, V. parahaemolyticus and V. tubiashii) and Aeromonas (A. hydrophila and A. salmonicida). No mortality occurred 14 days after zebra ¢sh and 7 days after mantis shrimp were intraperitoneally injected with JG1 at 10 6 CFU per animal, and 7 days after scallop and clam were immersed in JG1 at 10 7 CFU mL À 1 . A good antagonistic e¡ect on several bacterial pathogens and nontoxicity to the above-mentioned animals make JG1 a potential probiotic in aquaculture. In addition, a fast detection technique based on polymerase chain reaction ampli¢cation of the gyrB gene was established to allow us to determine the fate of JG1 when it is applied in aquaculture in the future.
We developed a simple and efficient method to construct 3D and 2D opal and inverse opal cellulose photonic crystal films (CPCF) by embedding 3D or 2D polymethyl methacrylate (PMMA) colloidal arrays into carboxymethyl cellulose (CMC), respectively.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.