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1.
Nanoscale Horiz ; 9(5): 731-741, 2024 Apr 29.
Artículo en Inglés | MEDLINE | ID: mdl-38505973

RESUMEN

Phototherapy shows great potential for pinpoint tumour treatment. Heptamethine cyanine dyes like IR783 have high potential as agents for antitumour phototherapy due to their inherent tumour targeting ability, though their effectiveness in vivo is unsatisfactory for clinical translation. To overcome this limitation, we present an innovative strategy involving IR783-based polymeric nanoassemblies that improve the dye's performance as an antitumoural photosensitizer. In the formulation, IR783 is modified with cysteamine and used to initiate the ring-opening polymerization (ROP) of the N-carboxyanhydride of benzyl-L-aspartate (BLA), resulting in IR783-installed poly(BLA). Compared to free IR783, the IR783 dye in the polymer adopts a twisted molecular conformation and tuned electron orbital distribution, remarkably enhancing its optical properties. In aqueous environments, the polymers spontaneously assemble into nanostructures with 60 nm diameter, showcasing surface-exposed IR783 dyes that function as ligands for cancer cell and mitochondria targeting. Moreover, the nanoassemblies stabilized the dyes and enhanced the generation of reactive oxygen species (ROS) upon laser irradiation. Thus, in murine tumor models, a single injection of the nanoassemblies with laser irradiation significantly inhibits tumour growth with no detectable off-target toxicity. These findings highlight the potential for improving the performance of heptamethine cyanine dyes in antitumor phototherapy through nano-enabled strategies.


Asunto(s)
Carbocianinas , Especies Reactivas de Oxígeno , Especies Reactivas de Oxígeno/metabolismo , Humanos , Animales , Ratones , Carbocianinas/química , Fármacos Fotosensibilizantes/química , Fármacos Fotosensibilizantes/farmacología , Fármacos Fotosensibilizantes/uso terapéutico , Fototerapia/métodos , Línea Celular Tumoral , Neoplasias/tratamiento farmacológico , Antineoplásicos/química , Antineoplásicos/farmacología , Antineoplásicos/efectos de la radiación , Antineoplásicos/uso terapéutico , Polímeros/química , Nanoestructuras/química , Nanoestructuras/uso terapéutico
2.
Org Biomol Chem ; 21(7): 1537-1548, 2023 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-36723045

RESUMEN

We developed an efficient method to achieve the regioselective acyl migration of benzoyl ester. In all the cases, the reactions required only the commercially available organic acid catalyst TsOH·H2O. This method enables the benzoyl group to migrate from secondary groups to primary hydroxyl groups, or from equatorial secondary hydroxyl groups to axial hydroxyl groups. The 1,2 or 1,3 acyl migration would potentially occur via five- and six-membered cyclic ortho acid intermediates. A wide range of orthogonally protected monosaccharides, which are useful intermediates for the synthesis of natural oligosaccharides, were synthesized. Finally, to demonstrate the utility of the method, a tetrasaccharide portion from a mycobacterial cell wall polysaccharide was assembled.

3.
Sensors (Basel) ; 22(6)2022 Mar 10.
Artículo en Inglés | MEDLINE | ID: mdl-35336320

RESUMEN

Considering that the actual operating environment of UAV is complex and easily disturbed by the space environment of urban buildings, the RoutE Planning Algorithm of Resilience Enhancement (REPARE) for UAV 3D route planning based on the A* algorithm and artificial potential fields algorithm is carried out in a targeted manner. First of all, in order to ensure the safety of the UAV design, we focus on the capabilities of the UAV body and build a risk identification, assessment, and modeling method such that the mission control parameters of the UAV can be determined. Then, the three-dimensional route planning algorithm based on the artificial potential fields algorithm is used to ensure the safe operation of the UAV online and in real time. At the same time, by adjusting the discriminant coefficient of potential risks in real time to deal with time-varying random disturbance encountered by the UAV, the resilience of the UAV 3D flight route planning can be improved. Finally, the effectiveness of the algorithm is verified by the simulation. The simulation results show that the REPARE algorithm can effectively solve the traditional route planning algorithm's insufficiency in anti-disturbance. It is safer than a traditional A* route planning algorithm, and its running time is shorter than that of the traditional artificial potential field route planning algorithm. It solves the problems of local optimization, enhances the UAV's ability to tolerate general uncertain disturbances, and eventually improves resilience of the system.

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