In Vitro Photoselective Gene Transfection of Hepatocellular Carcinoma Cells with Hypericin Lipopolyplexes.

The lipopolyplex, a multicomponent nonviral gene carrier, generally demonstrates superior colloidal stability, reduced cytotoxicity, and high transfection efficiency. In this study, a new concept, photochemical reaction-induced transfection, using photosensitizer (PS)-loaded lipopolyplexes was applied, which led to enhanced transfection and cytotoxic effects by photoexcitation of the photosensitizer. Hypericin, a hydrophobic photosensitizer, was encapsulated in the lipid bilayer of liposomes. The preformed nanosized hypericin liposomes enclosed the linear polyethylenimine (lPEI)/pDNA polyplexes, resulting in the formation of hypericin lipopolyplexes (Hy-LPP). The diameters of Hy-LPP containing 50 nM hypericin and 0.25 µg of pDNA were 185.6 ± 7.74 nm and 230.2 ± 4.60 nm, respectively, measured by dynamic light scattering (DLS) and atomic force microscopy (AFM). Gel electrophoresis confirmed the encapsulation of hypericin and pDNA in lipopolyplexes. Furthermore, in vitro irradiation of intracellular Hy-LPP at radiant exposures of 200, 600, and 1000 mJ/cm2 was evaluated. It demonstrated 60- to 75-fold higher in vitro luciferase expression than that in nonirradiated cells. The lactate dehydrogenase (LDH) assay supported that reduced transfection was a consequence of photocytotoxicity. The developed photosensitizer-loaded lipopolyplexes improved the transfection efficiency of an exogenous gene or induced photocytotoxicity; however, the frontier lies in the applied photochemical dose. The light-triggered photoexcitation of intracellular hypericin resulted in the generation of reactive oxygen species (ROS), leading to photoselective transfection in HepG2 cells. It was concluded that the two codelivered therapeutics resulted in enhanced transfection and a photodynamic effect by tuning the applied photochemical dose.

The effect of perceptual-motor continuity compatibility on the temporal control of continuous and discontinuous self-paced rhythmic movements.

One of the questions yet to be fully understood is to what extent the properties of the sensory and the movement information interact to facilitate sensorimotor integration. In this study, we examined the relative contribution of the continuity compatibility between motor goals and their sensory outcomes in timing variability. The variability of inter-response intervals was measured in a synchronization-continuation paradigm. Participants performed two repetitive movement tasks whereby they drew circles either using continuous or discontinuous self-paced movements while receiving discrete or continuous auditory feedback. The results demonstrated that the effect of perceptual-motor continuity compatibility may be limited in self-paced auditory-motor synchronization as timing variability was not significantly influenced by the continuity of the feedback or the continuity compatibility between feedback and the movement produced. In addition, results suggested that the presence of salient perceptual events marking the completion of the time intervals elicited a common timing process in both continuous and discontinuous circle drawing, regardless of the continuity of the auditory feedback. These findings open a new line of investigation into the role of the discriminability and reliability of the event-based information in determining the nature of the timing mechanisms engaged in continuous and discontinuous self-paced rhythmic movements.

Development and evaluation of a novel music-based therapeutic device for upper extremity movement training: A pre-clinical, single-arm trial.

Restoration of upper limb motor function and patient functional independence are crucial treatment targets in neurological rehabilitation. Growing evidence indicates that music-based intervention is a promising therapeutic approach for the restoration of upper extremity functional abilities in neurologic conditions such as cerebral palsy, stroke, and Parkinson's Disease. In this context, music technology may be particularly useful to increase the availability and accessibility of music-based therapy and assist therapists in the implementation and assessment of targeted therapeutic goals. In the present study, we conducted a pre-clinical, single-arm trial to evaluate a novel music-based therapeutic device (SONATA) for upper limb extremity movement training. The device consists of a graphical user interface generated by a single-board computer displayed on a 32" touchscreen with built-in speakers controlled wirelessly by a computer tablet. The system includes two operational modes that allow users to play musical melodies on a virtual keyboard or draw figures/shapes whereby every action input results in controllable sensory feedback. Four motor tasks involving hand/finger movement were performed with 21 healthy individuals (13 males, aged 26.4 ± 3.5 years) to evaluate the device's operational modes and main features. The results of the functional tests suggest that the device is a reliable system to present pre-defined sequences of audiovisual stimuli and shapes and to record response and movement data. This preliminary study also suggests that the device is feasible and adequate for use with healthy individuals. These findings open new avenues for future clinical research to further investigate the feasibility and usability of the SONATA as a tool for upper extremity motor function training in neurological rehabilitation. Directions for future clinical research are discussed.