pH-Activatable Organic Nanoparticles for Efficient Low-Temperature Photothermal Therapy of Ocular Bacterial Infection.

Low-temperature photothermal therapy (PTT) systems constructed by integrating organic photothermal agents with other bactericidal components that initiate bacterial apoptosis at low hyperthermia possess a promising prospect. However, these multicomponent low-temperature PTT nanoplatforms have drawbacks in terms of the tedious construction process, suboptimal synergy effect of diverse antibacterial therapies, and high laser dose needed, compromising their biosafety in ocular bacterial infection treatment. Herein, a mild PTT nanotherapeutic platform is formulated via the self-assembly of a pH-responsive phenothiazinium dye. These organic nanoparticles with photothermal conversion efficiency up to 84.5% necessitate only an ultralow light dose of 36 J/cm2 to achieve efficient low-temperature photothermal bacterial inhibition at pH 5.5 under 650 nm laser irradiation. In addition, this intelligent mild photothermal nanoplatform undergoes negative to positive charge reversion in acid biofilms, exhibiting good penetration and highly efficient elimination of drug-resistant E. coli biofilms under photoirradiation. Further in vivo animal tests demonstrated efficient bacterial elimination and inflammatory mitigation as well as superior biocompatibility and biosafety of the photothermal nanoparticles in ocular bacterial infection treatment. Overall, this efficient single-component mild PTT system featuring simple construction processes holds great potential for wide application and clinical transformation.

Characteristics of selected indoor air pollutants from moxibustion.

Concentrations and risk of monoaromatic hydrocarbons (MAHC), formaldehyde (HCHO), and polycyclic aromatic hydrocarbons (PAHs) in two moxibustion rooms were determined. The mean concentrations of MAHC, HCHO and PAHs were 535.2 µg/m(3), 157.9 µg/m(3) and 12.86µg/m(3), respectively, with notable health risks, indicating relatively serious pollution in indoor air due to the use of burning moxa. The indoor emissions of target pollutants from burning moxa in test chamber were also investigated. Toluene, benzene and xylene appeared to be dominant MAHCs, and naphthalene (NA) the dominant PAH, which were consistent with the pollution levels of the detected moxibustion rooms. The emission characteristics of smoky moxa and mild moxa were much in common and relatively close to that of tobacco; while that of smoke-free moxa showed a distinction. Though pollutants emission patterns varied within the three types of moxa, all of them had apparently higher emission intensities than other typical indoor sources, including tobacco. The results of this study can offer some references during the selection of moxa sticks and application of moxibustion.