Image-guided combined chemo-thermal therapy assists in optimizing treatment time, enhancing therapeutic efficiency, and circumventing side effects. In the present study, we developed a chemo-photothermal theranostic platform based on polydopamine (PDA)-coated gold nanorods (GNRs). The PDA coating was thin; however, it significantly suppressed the cytotoxicity of the cetyltrimethylammonium bromide template and allowed high cisplatin loading efficiency, arginine-glycine-aspartic acid (RGD) peptide (c(RGDyC)) conjugation, and chelator-free iodine-125 labeling (RGD-IPt-PDA@GNRs). While loaded cisplatin was released in a pH-sensitive manner, labeled I was outstandingly stable under biological conditions. RGD-IPt-PDA@GNRs had a high specificity for αvβ integrin, and consequently, they could selectively accumulate in tumors, as revealed by single photon emission computed tomography/CT imaging, and in target tumor angiogenic vessels, as shown by high-resolution photoacoustic imaging. As RGD-IPt-PDA@GNRs targets tumor angiogenesis, it is a highly potent tumor therapy. Combined chemo-photothermal therapy with probes could thoroughly ablate tumors and inhibit tumor relapse via a synergistic antitumor effect. Our studies demonstrated that RGD-IPt-PDA@GNRs is a robust platform for image-guided, chemo-thermal tumor therapy with outstanding synergistic tumor killing and relapse inhibition effects.

Indocyanine green-loaded mesoporous silica-coated gold nanorods (ICG-loaded Au@SiO2) were prepared for the dual capability of X-ray computed tomography (CT) and fluorescence imaging. X-ray CT scanning showed that ICG-loaded Au@SiO2 could provide significant contrast enhancement; Near-infrared fluorescence generated by the nanomaterial was present up to 12 h post intratumoral injection, thus enabling ICG-loaded Au@SiO2 to be used as a promising dual mode imaging contrast agent. Multiplexed images can be more easily obtained with this novel type of multimodal nanostructure compared with traditional contrast agents. The dual mode imaging probe has great potential for use in applications such as cancer targeting, molecular imaging in combination with radiotherapy, and photothermolysis.

PURPOSE: To investigate air puff induced corneal vibrations and their relationship to the intraocular pressure (IOP), viscoelasticity, mass, and elasticity of the cornea based on theoretical simulations and preliminary clinical observations. METHODS:To simulate the corneal movement during air puff deformation, a kinematic viscoelastic corneal model was developed involving the factors of corneal mass, damping coefficient, elasticity, and IOP. Different parameter values were taken to investigate how factors would affect the corneal movements. Two clinical ocular instruments, CorVis ST (Oculus Optikgeräte GmbH, Wetzlar, Germany) and the Ocular Response Analyzer (ORA; Reichert, Inc., Buffalo, NY), were employed to observe the corneal dynamical behaviors. RESULTS:Numerical results showed that during the air puff deformation, there would be vibrations along with the corneal deformation, and the damping viscoelastic response of the cornea had the potential to reduce the vibration amplitude. With consistent IOP, the overall vibration amplitude and inward motion depths were smaller with a stiffer cornea.CONCLUSIONS: A kinematic viscoelastic model of the cornea is presented to illustrate how the vibrations are associated with factors such as corneal mass, viscoelasticity, and IOP. Also, the predicted corneal vibrations during air puff deformation were confirmed by clinical observation.[J Refract Surg. 2014;30(3):208-213.]

We proposed a dual focus dual channel spectral domain optical coherence tomography (SD-OCT) for simultaneous imaging of the whole eye segments from cornea to the retina. By using dual channels the system solved the problem of limited imaging depth of SD-OCT. By using dual focus the system solved the problem of simultaneous light focusing on the anterior segment of the eye and the retina. Dual focusing was achieved by adjusting the collimating lenses so the divergence of the two probing beams was tuned to make them focused at different depth in the eye. We further achieved full range complex (FRC) SD-OCT in one channel to increase the depth range for anterior segment imaging. The system was successfully tested by imaging a human eye in vivo.

The morphologies of gold nanoparticles (NPs) affect their tumor accumulation through enhanced permeability and retention effect. However, detailed information and mechanisms of NPs' characteristics affecting tumor accumulation are limited. The aim of this study is to evaluate the effects of shape and active targeting ligands of theranostic NPs on tumor accumulation and therapeutic efficacy, and to elucidate the underlying mechanism. Methods: αvβ3 integrin-targeted, cisplatin-loaded and radioisotope iodine-125 labeled spherical and rod-shaped gold nano theranostic probes (RGD- 125 IPt-AuNPs and RGD- 125 IPt-AuNRs) with similar sizes were fabricated and characterized. The in vivo distribution and chemo-radio therapeutic efficacy against tumors of these newly developed probes were subsequently evaluated. Moreover, a physiologically based pharmacokinetic (PBPK) model was developed to characterize the in vivo kinetics of these probes at the sub-organ level, and to reveal the mechanism of NPs' shape and active targeting ligands effects on tumor accumulation. Result: Cisplatin and iodine-125 were loaded sequentially onto the NPs through a thin polydopamine coating layer on the NPs. Both RGD- 125 IPt-AuNPs and RGD- 125 IPt-AuNRs exhibited high specificity for αvβ3 in vitro , with the rod-shaped probe being more efficient. The PBPK model revealed that rod-shaped gold NPs diffused more rapidly in tumor interstitial than the spherical ones. Tumor accumulations of non-targeted and rod-shaped RAD- 125 IPt-AuNRs was higher in short term (1 h post injection), but not pronounced and similar to that of non-targeted spherical RAD- 125 IPt-AuNPs in 24 h after intravenous injection, revealing that the NPs' shape did not have a significant impact on tumor accumulations through enhanced permeability and retention (EPR) effect in long-term. While for actively targeted NPs, in addition to a higher distribution coefficient, RGD- 125 IPt-AuNRs also had a much higher tumor maximum uptake rate constant than RGD- 125 IPt-AuNPs, indicating both the shape and active targeting ligands affected the tumor uptake of rod-shaped NPs. As a result, RGD- 125 IPt-AuNRs had a more effective inhibition of tumor growth than RGD- 125 IPt-AuNPs by chemo-radiationtherapy. Conclusion: Our study suggests that both the shape and active targeting ligands of gold NPs play important roles on tumor accumulation and chemo-radio therapeutic effect.