Cerium-based nanoparticles for cancer photodynamic therapy

Metal-and metal-oxide-based nanoparticles have been widely exploited in cancer photodynamic therapy(PDT).Among these materials,cerium-based nanoparticles have drawn extensive attention due to their superior biosafety and distinctive physicochemical properties,especially the reversible transition between the valence states of Ce(Ⅲ)and Ce(Ⅳ).In this review,the recent advances in the use of cerium-based nanoparticles as novel photosensitizers for cancer PDT are discussed,and the activation mechanisms for electron transfer to generate singlet oxygen are presented.In addition,the types of cerium-based nanoparticles used for PDT of cancer are summarized.Finally,the challenges and prospects of clinical translations of cerium-based nanoparticles are briefly addressed.

Orthogonal Aza-BODIPY–BODIPY dyad as heavy-atom free photosensitizer for photo-initiated antibacterial therapy

Photodynamic antibacterial therapy shows great potential in bacterial infection and the reactive oxygen species(ROS)production of the photosensitizers is crucial for the therapeutic e®ect.Introducing heavy atoms is a common strategy to enhance photodynamic performance,while dark toxicity can be induced to impede further clinical application.Herein,a novel halogen-free photosensitizer Aza-BODIPY-BODIPY dyad NDB with an orthogonal molecular conguration was synthesized for photodynamic antibacterial therapy.The absorption and emission peaks of NDB photosensitizer in toluene were observed at 703 nm and 744 nm,respectively.The°uorescence(FL)lifetime was measured to be 2.8 ns in toluene.Under 730 nm laser illumination,the ROS generation capability of NDB was 3-fold higher than that of the commercial ICG.After nanoprecipitation,NDB NPs presented the advantages of high photothermal conversion e±ciency(39.1%),good photostability,and excellent biocompatibility.More importantly,in vitro antibacterial assay conrmed that the ROS and the heat generated by NDB NPs could extirpate methicillin-resistant S.aureus e®ectively upon exposure to 730 nm laser,suggesting the potential application of NDB NPs in photo-initiated antibacterial therapy.

Effect of blood sampling management on reducing blood transfusions in very preterm infants

To the Editor:Unstable clinical conditions and complications make multiple laboratory tests and blood sampling inevitable in preterm infants,contributing to iatrogenic blood loss.Undoubtedly,iatrogenic blood loss is highly correlated with red blood cell transfusion(RBCT).A previous study on extremely low birth weight(BW)infants reported that the sampling blood loss was 30.0 mL/kg within the first week of life,leading to one or more RBCTs in 98%of patients.[1]RBCTs are increasingly reported to cause inflammatory responses and increase the incidence of preterm complications.Therefore,reducing iatrogenic blood loss could not only decrease the need for transfusions but also reduce the risk of neonatal mortality and morbidity.

Protective effect of periplaneta americana extract on intestinal mucosal barrier function in patients with sepsis

OBJECTIVE: To investigate the effect of the periplaneta americana extract on the intestinal mucosal barrier and prognostic implications in patients with sepsis. METHODS: Sixty and six patients with sepsis were assigned randomly to treatment group (32 cases) and control group (32 cases). The extractfrom periplaneta americana plus conventional medication for sepsis was administered to the treatment group, while the control group only received conventional treatment. The gastrointestinal function scores and acute physiology and chronic health evaluation II (APACHEⅡ) scores of all subjects were documented at baseline, at days 1, 3 and 7 after treatment respectively and their blood endotoxin was tested at the same time points as well.The incidence of death was recorded for both groups throughout the trial. RESULTS: At days 3 and 7 after treatment, gastroin-testinal function score, APACHE II, and endotoxin level in treatment group wasbetter than that in control group and the difference between them was significant (both P<0.05). Although the incidence of death in treatment group was less than that in control group, the difference between the two groups was not significant (P> 0.05). CONCLUSION: The extract of periplaneta americana had protective effect on intestinal mucosal barrier and could improve the condition and prognosis in patients with sepsis.

Multifunctional shape-dependent plasmonic nanoprobe by enzymatic etching of single gold triangular nanoplate

Hydrogen peroxide(H2O2),as a signaling molecule,plays a vital role in a wide variety of signaling transduction processes,aging,and diseases.However,the excessive production of H2O2 causes various diseases.Herein,we develop a novel method for H2O2 detection in live cells via dark-field scattering spectroscopy with gold triangular nanoprisms(AuTNPs)as probes.The corners of AuTNPs would be gradually oxidatively etched by the strong coordination of Br•which is generated by enzymatic reactions in the presence of horseradish peroxidase(HRP),bromide ion and trace hydrogen peroxide.Benefitting from the morphological change,the single AuTNP based plasmonic nanoprobe shows notable blueshifts and scattering color changes which could be real-time monitored under the dark-field microscopy.The peak position in the scattering spectra of individual AuTNP blueshifts linearly with the increase of H2O2 concentration,and exhibits high sensitivity to H2O2 in a large range from 2.5 to 100µM with a low detection limit(LOD)of 0.74µM.Moreover,the experimental results were supported by the simulated results via the finite-difference time-domain(FDTD)method.The nanoprobes have been further used for intracellular H2O2 detection in live cells.Besides,the etching of AuTNP also provides an alternative method to design novel plasmonic logic chips and write-once plasmonic memories.