Musical Neurofeedback Advancements, Feedback Modalities, and Applications: A Systematic Review.

The field of EEG-Neurofeedback (EEG-NF) training has showcased significant promise in treating various mental disorders, while also emerging as a cognitive enhancer across diverse applications. The core principle of EEG-NF involves consciously guiding the brain in desired directions, necessitating active engagement in neurofeedback (NF) tasks over an extended period. Music listening tasks have proven to be effective stimuli for such training, influencing emotions, mood, and brainwave patterns. This has spurred the development of musical NF systems and training protocols. Despite these advancements, there exists a gap in systematic literature that comprehensively explores and discusses the various modalities of feedback mechanisms, its benefits, and the emerging applications. Addressing this gap, our review article presents a thorough literature survey encompassing studies on musical NF conducted over the past decade. This review highlights the several benefits and applications ranging from neurorehabilitation to therapeutic interventions, stress management, diagnostics of neurological disorders, and sports performance enhancement. While acknowledged for advantages and popularity of musical NF, there is an opportunity for growth in the literature in terms of the need for systematic randomized controlled trials to compare its effectiveness with other modalities across different tasks. Addressing this gap will involve developing standardized methodologies for studying protocols and optimizing parameters, presenting an exciting prospect for advancing the field.

Development of a Novel, Automated High-Throughput Device for Performing the Comet Assay.

A comet assay is a trusted and widely used method for assessing DNA damage in individual eukaryotic cells. However, it is time-consuming and requires extensive monitoring and sample manipulation by the user. This limits the throughput of the assay, increases the risk of errors, and contributes to intra- and inter-laboratory variability. Here, we describe the development of a device which automates high throughput sample processing for a comet assay. This device is based upon our patented, high throughput, vertical comet assay electrophoresis tank, and incorporates our novel, patented combination of assay fluidics, temperature control, and a sliding electrophoresis tank to facilitate sample loading and removal. Additionally, we demonstrated that the automated device performs at least as well as our "manual" high throughput system, but with all the advantages of a fully "walkaway" device, such as a decreased need for human involvement and a decreased assay run time. Our automated device represents a valuable, high throughput approach for reliably assessing DNA damage with the minimal operator involvement, particularly if combined with the automated analysis of comets.

Probing the biocompatibility of MoS2 nanosheets by cytotoxicity assay and electrical impedance spectroscopy.

Transition metal dichalgogenides such as MoS2 have recently emerged as hot two-dimensional (2D) materials due to their superior electronic and catalytic properties. Recently, we have reported the usefulness of MoS2 nanosheets toward the electrochemical detection of neurotransmitters and glucose (Narayanan et al 2014 Nanotechnology 25 335702). Furthermore, there are reports available in the literature that demonstrate the usefulness of MoS2 nanosheets for biosensing and energy storage applications (Zhu et al 2013 J. Am. Chem. Soc. 135 5998-6001; Pumera and Loo 2014 Trends Anal. Chem. 61 49-53; Lee et al 2014 Sci. Rep. 4 7352; Stephenson et al 2014 Energy Environ. Sci. 7 209-31). Understanding the cytotoxic effect of any material is very important prior to employing them for any in vivo biological applications such as implantable sensors, chips, or carriers for drug delivery and cell imaging purposes. Herein, we report the cytotoxicity of the MoS2 nanosheets based on the cytotoxic assay results and electrical impedance analysis using rat pheochromocytoma cells (PC12) and rat adrenal medulla endothelial cells (RAMEC). Our results indicated that the MoS2 nanosheets synthesized in our work are safe 2D nanosheets for futuristic biomedical applications.

Lab-on-chip device for single cell trapping and analysis.

Traditional cell assay gives us an average result of multiple cells and it is assumed that the resultant is the outcome of all cells in population. However, single cell studies have revealed that individual cells of same type may differ dramatically and these differences may have important role to play in cells functionality. Such information can be obscured in only studying cell population experimental approach. To uncover biological principles and ultimately to improve the detection and treatment of disease, new approaches are highly required to single cell analysis. We propose to fabricate a lab on chip device to study high throughput single cell nanotoxicity analysis. The chip incorporates independently addressable active microwell electrodes for cell manipulation and analysis. We employed positive-dielectrophoresis approach to quickly and efficiently capture single cells in each wells with having control over individual microwells. We examined change in impedance properties to verify cell capture in microwell and its health and present a novel model of single cell assay for nanotoxicity, and drug testing.

Chip based single cell analysis for nanotoxicity assessment.

Nanomaterials, because of their tunable properties and performances, have been utilized extensively in everyday life related consumable products and technology. On exposure, beyond the physiological range, nanomaterials cause health risks via affecting the function of organisms, genomic systems, and even the central nervous system. Thus, new analytical approaches for nanotoxicity assessment to verify the feasibility of nanomaterials for future use are in demand. The conventional analytical techniques, such as spectrophotometric assay-based techniques, usually require a lengthy and time-consuming process and often produce false positives, and often cannot be implemented at a single cell level measurement for studying cell behavior without interference from its surrounding environment. Hence, there is a demand for a precise, accurate, sensitive assessment for toxicity using single cells. Recently, due to the advantages of automation of fluids and minimization of human errors, the integration of a cell-on-a-chip (CoC) with a microfluidic system is in practice for nanotoxicity assessments. This review explains nanotoxicity and its assessment approaches with advantages/limitations and new approaches to overcome the confines of traditional techniques. Recent advances in nanotoxicity assessment using a CoC integrated with a microfluidic system are also discussed in this review, which may be of use for nanotoxicity assessment and diagnostics.

A paper electrode integrated lateral flow immunosensor for quantitative analysis of oxidative stress induced DNA damage.

A novel device combining electrochemical and colorimetric detection is developed for the rapid measurement of 8-hydroxy-2'-deoxyguanosine (8-OHdG), a DNA oxidative damage biomarker. The device takes advantage of the speed and low cost of the conventional strip test as well as the high reliability and accuracy of the electrochemical assay. Competitive immunoreactions were performed on the lateral flow strip, and the captured 8-OHdG on the control line was determined by chronoamperometric measurement with carbon nanotube paper as the working electrode. At the same time, the color intensity of the test line was measured by a scanner and analyzed by the ImageJ software. The device was able to detect 8-OHdG concentrations in PBS as low as 2.07 ng mL(-1) by the colorimetric method and 3.11 ng mL(-1) by the electrochemical method. Furthermore, the device was successfully utilized to detect 8-OHdG in urine with a detection limit of 5.76 ng mL(-1) (colorimetric method) and 8.85 ng mL(-1) (electrochemical method), respectively. In conclusion, the integrated device with dual detection methods can provide a rapid, visual, quantitative and feasible detection method for 8-OHdG. The integration of these two methods holds two major advantages over tests based on a single method. Firstly, it can provide double confidence on the same assay. Secondly, by involving two methods that differ in principle, the integration could potentially avoid false results coming from one method. In addition, these methods do not require expensive equipment or trained personnel, making it suitable for use as a simple, economical, portable field kit for on-site monitoring of 8-OHdG in a variety of clinical settings.

Breaking the fluoride diffusion barrier with combined dielectrophoresis and AC electroosmosis.

PURPOSE: To compare the deposition of fluoride particles into bovine enamel by diffusion (n = 20); dielectrophoresis (DEP) at 10 Hz and 5000 Hz (n = 10); and DEP (10 Hz and 5000 Hz) combined with AC electroosmosis (ACEO) at 400 Hz (DEP/ACE) (n = 10). METHODS: Fluoride particle movements induced at 10, 400, and 5000 Hz frequencies, were analyzed with light microscopy and stack imaging in real time. Fluoride concentrations were measured at various enamel depths using wavelength dispersive spectrometry. Results were analyzed by ANOVA/Student-Newman-Keuls post hoc (P = 0.05). RESULTS: Fluoride levels in teeth treated with DEP were significantly higher than diffusion at depths 10 and 20 microm. DEP and diffusion were relatively ineffective at greater depths. The highest fluoride concentrations at 10, 20, and 50 microm depths were found in the DEP/ACE group. After 20 minutes, DEP/ACE increased fluoride uptake by 600% at 50 microm and 400% at 100 microm compared to baseline levels (P < 0.05). Fluoride particle movement was induced by negative DEP at 10 Hz; positive DEP at 5000 Hz; and ACEO at 400 Hz frequency.

A Review of Engineering Approaches for Lymphedema Detection.

Edema is a condition characterized by excessive swelling of a tissue due to an abnormal accumulation of interstitial fluid in the subcutaneous tissue. More specifically, disruption of the lymphatic system causes what is known as lymphedema. This condition is commonly seen in breast cancer survivors postradiotherapy treatment, chemotherapy, and surgeries; this population has shown high risk of developing lymphedema in the limbs. Throughout the years, several techniques have been developed and implemented for the detection and measurement of lymphedema, including techniques to measure the diseased limb volume, electrical techniques to measure the water content in tissues, and optical techniques to measure either tissue absorbance or limb volume. However, there is still no method that allows for continuous monitoring of the disease and provides a better understanding of its progression. This study describes the different approaches that have been used and that could be used for lymphedema measurement.

Microelectromechanical System-Based Sensing Arrays for Comparative in Vitro Nanotoxicity Assessment at Single Cell and Small Cell-Population Using Electrochemical Impedance Spectroscopy.

The traditional in vitro nanotoxicity assessment approaches are conducted on a monolayer of cell culture. However, to study a cell response without interference from the neighbor cells, a single cell study is necessary; especially in cases of neuronal, cancerous, and stem cells, wherein an individual cell's fate is often not explained by the whole cell population. Nonetheless, a single cell does not mimic the actual in vivo environment and lacks important information regarding cell communication with its microenvironment. Both a single cell and a cell population provide important and complementary information about cells' behaviors. In this research, we explored nanotoxicity assessment on a single cell and a small cell population using electrochemical impedance spectroscopy and a microelectromechanical system (MEMS) device. We demonstrated a controlled capture of PC12 cells in different-sized microwells (to capture a different number of cells) using a combined method of surface functionalization and dielectrophoresis. The present approach provides a rapid nanotoxicity response as compared to other conventional approaches. This is the first study, to our knowledge, which demonstrates a comparative response of a single cell and small cell colonies on the same MEMS platform, when exposed to metaloxide nanoparticles. We demonstrated that the microenvironment of a cell is also accountable for cells' behaviors and their responses to nanomaterials. The results of this experimental study open up a new hypothesis to be tested for identifying the role of cell communication in spreading toxicity in a cell population.

Electrochemical monitoring-on-chip (E-MoC) of HIV-infection in presence of cocaine and therapeutics.

Electrochemical monitoring-on-chip (E-MoC)-based approach for rapid assessment of human immunodeficiency virus (HIV)-infection in the presence of cocaine (Coc) and specific drugs namely i.e., tenofovir (Tef), rimcazole (RA) is demonstrated here, for the first time, using electrochemical impedance spectroscopy (EIS). An in-vitro primary human astrocytes (HA) model was developed using a cultureware chip (CC, used for E-MoC) for HIV-infection, Coc exposure and treatment with anti-HIV drug i.e., Tef, and Coc antagonist i.e., RA. The charge transfer resistance (Rct) value of each CC well varies with respect to infection and treatment demonstrated highly responsive sensitivity of developed chip. The results of E-MoC, a proof-of-the concept, suggested that HIV-infection progression due to Coc ingestion and therapeutic effects of highly specific drugs are measurable on the basis of cell electrophysiology. Though, this work needs various molecular biology-based optimizations to promote this technology as an analytical tool for the rapid assessment of HIV-infection in a patient to manage HIV diseases for timely diagnosis. The presented study is based on using CNS cells and efforts are being made to perform this method using peripheral cells such as monocytes derived dendritic cells.

Development of paper-based analytical kit for point-of-care testing.

Paper-based analytical devices have been widely used for biomedical, environmental and food-quality testing. This review focuses on paper-based tests for biomarkers and bacterial detection with a brief introduction about various fabrication techniques and designs, biological and nonbiological probes and detection methods. Paper is relatively cheap and available in abundance. Moreover, properties of paper such as it being disposable, easy to use and store, and that it is easy to transport and modify draw significant attention to it as a platform for the development of paper-based analytical devices. These traits make paper-based analytical devices a strong candidate in point-of-care devices for rapid and economical testing near the site of patients.