Antibacterial polypeptides as ancient immune defense systems are effective against bacteria. Here we report a novel kind of “armed” carrier: an antibacterial polypeptide-grafted chitosan-based nanocapsule with an excellent antibacterial efficacy against both Gram-positive and Gram-negative bacteria. This nanocapsule also has excellent blood compatibility and low cytotoxicity. Patients after tumor surgery may benefit from this “armed” carrier because it is highly anti-inflammation and is able to deliver anticancer and antiepileptic drugs simultaneously.

New Delhi metallo-β-lactamase-1 (NDM-1) is the most prevalent type of metallo-β-lactamase and hydrolyzes almost all clinically used β-lactam antibiotics. Here we show that the antimicrobial peptide thanatin disrupts the outer membrane of NDM-1-producing bacteria by competitively displacing divalent cations on the outer membrane and inducing the release of lipopolysaccharides. In addition, thanatin inhibits the enzymatic activity of NDM-1 by displacing zinc ions from the active site, and reverses carbapenem resistance in NDM-1-producing bacteria in vitro and in vivo. Thus, thanatin’s dual mechanism of action may be useful for combating infections caused by NDM-1-producing pathogens.

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Cancer patients after chemotherapy may also suffer bacterial attack due to badly decreased immunity. Although with high bacterial efficacy, conventional antibiotics are prone to inducement of drug resistance and may be not suitable for some cancer patients. In contrast, antibacterial peptides are highly effective in inhibiting bacteria without inducing resistance in pathogens. Presented in this article is a novel kind of highly effective antibacterial peptide-based biocompatible and biodegradable block copolymer vesicle. The copolymer is poly(ε-caprolactone)-block-poly[phenylalanine-stat-lysine-stat-(lysine-folic acid)] [PCL19-b-poly[Phe12-stat-Lys9-stat-(Lys-FA)6]], which can self-assemble into vesicles in aqueous solution. The biocompatible and biodegradable PCL forms the vesicle membrane, whereas the poly[Phe12-stat-Lys9-stat-(Lys-FA)6] block constitutes the vesicle coronas. Compared to the individual polymer chains, the vesicles showed enhanced antibacterial activities against both Gram-positive and Gram-negative bacteria (16 μg mL(-1)) due to the locally concentrated antibacterial poly[Phe12-stat-Lys9-stat-(Lys-FA)6] coronas, which may avoid the inducement of antibiotic-resistant bacteria and side effects of multidrug interactions. Furthermore, folic acid is introduced into the vesicle coronas for potential further applications such as cancer-targeted drug delivery. Moreover, the amino groups can be further functionalized when necessary. This low cytotoxic, biocompatible, biodegradable, and antibacterial vesicle (without antibiotic resistance) may benefit patients after tumor surgery because it is highly anti-inflammatory, and it is possible to deliver the anticancer drug to tumor cells simultaneously.

We have studied numerically the shadows of a non-Kerr rotating compact object with quadrupole mass moment, which belongs to Manko-Novikov family. The non-integrable photon motion caused by quadrupole mass moment affects sharply the shadow of the compact object. As the deviation parameter related to quadrupole mass moment is negative, the shadow of compact object is prolate and there are two disconnected main shadows with eyebrows located symmetrically on both sides of the equatorial plane. As the deviation parameter is positive, the shadow becomes oblate and the main shadow is joined together in the equatorial plane. Moreover, in this positive cases, there is a disorder region in the left of shadow which increases with the quadrupole-deviation parameter.Interestingly, we also find that Einstein ring is broken as the deviation from Kerr metric is larger than a certain critical value. This critical value decreases with the rotation parameter of black hole.Especially, the observer on the direction of rotation axis will find some concentric bright rings in the black disc. Finally, supposing that the gravitational field of the supermassive central object of the galaxy described by this metric, we estimated the numerical values of the observables for the black hole shadow.