Search

Exosomes are membranous structures measuring between 40-120 nm that are secreted by various cells of the human body into the body fluid system. Exosomes contain proteins, mRNA, miRNA, and signaling molecules, and physiologically they assist in the intercellular transport of proteins and RNA molecules. In this study, we used an immunoaffinity filter paper platform combined with scanning electron microscopy and microfluidic systems to detect the size of exosomes within the aqueous humor. Eight aqueous humor samples showed three distinct sizes of exosomes that were significantly different on scanning electron microscopy( P  < 0.01). We further used nanoparticle tracking analysis to assess the size distribution of exosomes within the aqueous humor. We found significantly different distributions of exosomes between patients with three different ocular diseases and patients with normal cataracts as controls. An obvious peak of exomeres(size around 35 nm)was found in the patients with central retinal vein occlusion and vitreous hemorrhage. Flare-ups of large exosomes(size 90-120 nm)were found in the patients with the inflammatory ocular disease pars planitis. No obvious peaks in exomeres or large exosomes were found in the control group. There was a high association between the distribution of exosomes and the pathogenesis of ocular diseases. After intravitreal anti-vascular endothelial growth factor treatment, the aqueous humor from the patients with neovascular diseases showed a significant reduction in exosomes in nanoparticle tracking analysis. These findings suggest that at least three distinct sizes of exosomes exist in the aqueous humor:(1)exomeres:<35 nm;(2)small exosomes:60-80 nm; and (3)large exosomes:90-120 nm. Different sizes of exosomes may have different implications in normal or diseased eyes.

Transcranial temporal interference stimulation (tTIS) is a promising brain stimulation method that can target deep brain regions by delivering an interfering current from surface electrodes. Most instances of tTIS stimulate the brain with a single-frequency sinusoidal waveform generated by wave interference. Theta burst stimulation is an effective stimulation scheme that can modulate neuroplasticity by generating long-term potentiation- or depression-like effects. To broaden tTIS application, we developed a theta burst protocol using tTIS technique to modulate neuroplasticity in rats. Two cannula electrodes were unilaterally implanted into the intact skull over the primary motor cortex. Electrical field of temporal interference envelopes generated by tTIS through cannula electrodes were recorded from primary motor cortex. Theta burst schemes were characterized, and motor activation induced by the stimulation was also evaluated simultaneously by observing electromyographic signals from the corresponding brachioradialis muscle. After validating the stimulation scheme, we further tested the modulatory effects of theta burst stimulation delivered by tTIS and by conventional transcranial electrical stimulation on primary motor cortex excitability. Changes in the amplitude of motor evoked potentials, elicited when the primary motor cortex was activated by electrical pulses, were measured before and after theta burst stimulation by both techniques. Significant potentiation and suppression were found at 15 to 30 min after the intermittent and continuous theta burst stimulation delivered using tTIS, respectively. However, comparing to theta burst stimulations delivered using conventional form of transcranial electrical stimulation, using tTIS expressed no significant difference in modulating motor evoked potential amplitudes. Sham treatment from both methods had no effect on changing the motor evoked potential amplitude. The present study demonstrated the feasibility of using tTIS to achieve a theta burst stimulation scheme for motor cortical neuromodulation. These findings also indicated the future potential of using tTIS to carry out theta burst stimulation protocols in deep-brain networks for modulating neuroplasticity., (© 2024. The Author(s).)

Background: The current treatment options for overactive bladder (OAB) continue to pose challenges for refractory cases and may involve invasive procedures. To assess the potential benefit of non-invasive repetitive peripheral magnetic stimulation (rPMS) on sacral roots using intermittent theta burst stimulation (iTBS) as treatment option for OAB. The study involved a total of 33 rats, which were divided into three different experimental phases., Materials and Methods: To induce bladder overactivity rats were pretreated with a continuous transvesical infusion of 0.5% acetic acid (AA). During bladder infusion, the intravesical pressure was recorded using cystometrography (CMG) to investigate the effects of AA pretreatment and the therapeutic intervention of acute sacral rPMS using iTBS., Results: Pre-application of rPMS with iTBS at a 100% intensity significantly extended the mean first voiding time (Tv) in normal healthy rats to 132%. Acute rPMS iTBS at a 100% intensity resulted in a significant increase of the inter-contraction interval (ICI) to 121%. An AA model was established with continuous saline infusion after 0.5% AA treatment and resulted in significant reductions of Tv to 42% and ICI to 56% of the corresponding control values. Subsequently, rPMS iTBS at a 100% intensity on the sacral nerve effectively inhibited AA-induced bladder overactivity and significantly increased the ICI to 167%∼222%. No significant changes in maximum bladder pressure (Pmax) were found., Conclusions: Sacral nerve rPMS with iTBS demonstrated the ability to suppress AA-induced bladder overactivity. This promising modality could be developed as an alternative approach to enhance bladder continence in OAB syndrome patients., Competing Interests: Declaration of Competing Interest All authors declare that they have no known competing financial interests or personal relationships that could have potentially influenced the research reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier B.V. All rights reserved.)