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The technology of drug delivery systems (DDS) has expanded into many applications, such as for treating neurological disorders. Nanoparticle DDS offer a unique strategy for targeted transport and improved outcomes of therapeutics. Stroke is likely to benefit from the emergence of this technology though clinical breakthroughs are yet to manifest. This review explores the recent advances in this field and provides insight on the trends, prospects and challenges of translating this technology to clinical application. Carriers of diverse material compositions are presented, with special focus on the surface properties and emphasis on the similarities and inconsistencies among in vivo experimental paradigms. Research attention is scattered among various nanoparticle DDS and various routes of drug administration, which expresses the lack of consistency among studies. Analysis of current literature reveals lipid- and polymer-based DDS as forerunners of DDS for stroke; however, cell membrane-derived vesicles (CMVs) possess the competitive edge due to their innate biocompatibility and superior efficacy. Conversely, inorganic and carbon-based DDS offer different functionalities as well as varied capacity for loading but suffer mainly from poor safety and general lack of investigation in this area. This review supports the existing literature by systematizing presently available data and accounting for the differences in drugs of choice, carrier types, animal models, intervention strategies and outcome parameters.

Molecular mechanisms by which sex steroids interact with P. aeruginosa to modulate its virulence have yet to be reported. Our work provides the first characterization of a steroid-induced membrane stress mechanism promoting P. aeruginosa virulence, which includes the release of proinflammatory outer membrane vesicles, resulting in inflammation, host tissue damage, and reduced bacterial clearance. We further demonstrate that at nanomolar (physiological) concentrations, male and female sex steroids promote virulence in clinical strains of P. aeruginosa based on their dynamic membrane fluidic properties. This work provides, for the first-time, mechanistic insight to better understand and predict the P. aeruginosa related response to sex steroids and explain the interindividual patient variability observed in respiratory diseases such as cystic fibrosis that are complicated by gender differences and chronic P. aeruginosa infection., Estrogen, a major female sex steroid hormone, has been shown to promote the selection of mucoid Pseudomonas aeruginosa in the airways of patients with chronic respiratory diseases, including cystic fibrosis. This results in long-term persistence, poorer clinical outcomes, and limited therapeutic options. In this study, we demonstrate that at physiological concentrations, sex steroids, including testosterone and estriol, induce membrane stress responses in P. aeruginosa. This is characterized by increased virulence and consequent inflammation and release of proinflammatory outer membrane vesicles promoting in vivo persistence of the bacteria. The steroid-induced P. aeruginosa response correlates with the molecular polarity of the hormones and membrane fluidic properties of the bacteria. This novel mechanism of interaction between sex steroids and P. aeruginosa explicates the reported increased disease severity observed in females with cystic fibrosis and provides evidence for the therapeutic potential of the modulation of sex steroids to achieve better clinical outcomes in patients with hormone-responsive strains.

A stretchable and self-healable conductive material with high conductivity is critical to high-performance wearable electronics and integrated devices for applications where large mechanical deformation is involved. While there has been great progress in developing stretchable and self-healable conducting materials, it remains challenging to concurrently maintain and recover such functionalities before and after healing. Here, we report a highly stretchable and autonomic self-healable conducting film consisting of a conducting polymer (poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate), PEDOT:PSS) and a soft-polymer (poly(2-acrylamido-2-methyl-1-propanesulfonic acid, PAAMPSA). The optimal film exhibits outstanding stretchability as high as 630% and high electrical conductivity of 320 S/cm, while possessing the ability to repair both mechanical and electrical breakdowns when undergoing severe damage at ambient conditions. We further utilized this polymer composite film in a tactile sensor, which exhibits good pressure sensitivity of 164.5 kPa⁻1, near hysteresis-free, an ultrafast response time of 19 ms and excellent endurance over 1500 consecutive presses. Additionally, we successfully demonstrated an integrated 5 × 4 stretchable and self-healable organic electrochemical transistor (OECT) array with great device performance (including high transconductance of 12.95 ± 1.85 mS and good operational stability). The developed stretchable and autonomic self-healable conducting film significantly increases the practicality and shelf life of wearable electronics, which in turn, reduce maintenance costs and build-up of electronic waste. Submitted/Accepted version W.L.L would like to acknowledge funding support from National Robotics Programme (W1925d0106).

In order to automate the traditional manual process, in this paper, we demonstrate a visual-based method for sampling floor dust using a mobile microscopic platform. A floor cleaning robot with an onboard microscope is developed and deployed for the task of dust sampling. An extensive experimental study is conducted involving two sets of experiments where the first set involved three different types of sites and the second set involved three different dust types sprinkled on the same type of floor. The acquired 64 sample images from each experiment are stitched together for data logging and review purposes. The results substantiate our proposition of using a robotic platform with an onboard microscope for the automated visual sampling of floor dust. Results of the current study suggest that the proposed robotic platform could provide a viable method for the dust-sampling task in indoor settings.

Long gone is the time when tumors were thought to be insular masses of cells, residing independently at specific sites in an organ. Now, researchers gradually realize that tumors interact with the extracellular matrix (ECM), blood vessels, connective tissues, and immune cells in their environment, which is now known as the tumor microenvironment (TME). It has been found that the interactions between tumors and their surrounds promote tumor growth, invasion, and metastasis. The dynamics and diversity of TME cause the tumors to be heterogeneous and thus pose a challenge for cancer diagnosis, drug design, and therapy. As TME is significant in enhancing tumor progression, it is vital to identify the different components in the TME such as tumor vasculature, ECM, stromal cells, and the lymphatic system. This review explores how these significant factors in the TME, supply tumors with the required growth factors and signaling molecules to proliferate, invade, and metastasize. We also examine the development of TME-targeted nanotheranostics over the recent years for cancer therapy, diagnosis, and anticancer drug delivery systems. This review further discusses the limitations and future perspective of nanoparticle based theranostics when used in combination with current imaging modalities like Optical Imaging, Magnetic Resonance Imaging (MRI) and Nuclear Imaging (Positron Emission Tomography (PET) and Single Photon Emission Computer Tomography (SPECT)). MOE (Min. of Education, S’pore) Published version

Multifunctional superparamagnetic iron oxide nanoparticles have been used for years in cancer research for cancer theranostics in the biomedical field. To be used as a multifunctional theranostic probe specific for cancer cells, it requires to be conjugated with a targeting moiety which can make sure that the nanoparticles attaches only or atleast differently to the cancer cells comparing with the healthy cells. It also requires to be conjugated with a unique contrast agent of a specific imaging modality to validate its use in nanomedicine. SPIONs were first amine functionalized with three variations, thus making three different samples to be compared throughout the project. These samples were then attached with folic acid which is specific for folate receptor that is overexpressed in different types of cancer cells. Then, the SPION-Folic acid (SPION-FA) samples were attached with a fluorescent compound used for fluorescence microscopy, Fluoroisothiocyanate (FITC). These final products were tested for solubility, biocompatibility and the amount of cell uptake. The probes developed in this report can be used for both cell/ tissue imaging and also for invivo imaging. ​Master of Science (Biomedical Engineering)

Hybrid Imaging modalities have shown great potential in medical imaging and diagnosis. A more comprehensive and targeted view of neurological disorders can be achieved by blending the anatomical and functional perspectives through hybridization. With consistently improving technologies, there have been many developments in fused imaging techniques over the past few decades. This article provides an overview of various bimodal and trimodal hybrid imaging techniques being developed and explored for neuroimaging applications. Recent advancements and potentials are discussed for single photon emission computed tomography-computed tomography (SPECT-CT), positron emission tomography-CT (PET-CT), PET-magnetic resonance imaging (PET-MRI), electroencephalography-functional magnetic resonance imaging (EEG-fMRI), magnetoencephalography-fMRI (MEG-fMRI), EEG-near-infrared spectroscopy (EEG-NIRS), magnetic resonance-PET-EEG (MR-PET-EEG) and MR-PET-CT in the perspective of neuroimaging. A comparison of these hybrid approaches is provided on a single platform to analyze their performance on the basis of several common factors essential for imaging and analyzing neurological disorders and in vivo molecular processes. This article also provides an overview of recently developed advanced imaging technologies that are being hybridized with other imaging modalities and being explored as potential techniques for neuroscience. Novel approaches and clinical applications of hybrid neuroimaging are anticipated with inclusion of new technologies, better sensing capabilities, multimodal probes, and improved hybridization.