Social distancing during the COVID-19 pandemic: Potential impact and correlation with asthma.

BACKGROUND: Non-pharmaceutical interventions have been implemented globally to control the COVID-19 pandemic and have been shown to alleviate both allergies and respiratory infections. Although mask-wearing is an accepted non-pharmaceutical intervention, the effects of social distancing have not been thoroughly evaluated. OBJECTIVES: To evaluate the effects of social distancing on asthma trends in Seoul, South Korea. METHODS: This study included data from the National Health Insurance Service of South Korea, covering approximately 10 million people in Seoul. Daily and monthly data of patients with asthma from 2018 to 2021 were examined, and the degree of social distancing performance was measured using the number of subway users as an index. Pearson's correlation coefficient was used to determine the relationship between the two indices. The change-point detection technique, cross-correlation, and Granger causality method were used to assess the temporal causality between social distancing and asthma. RESULTS: The number of patients with asthma decreased by 42.4 % from 2019 to 2020, while that of subway users decreased by 26.3 % during this period. Pearson's correlation analysis revealed significant positive correlations. Asthma and subway users showed a significant change in incidence following the implementation of social distancing; subway users showed a causal relationship with patients with asthma. CONCLUSION: Our results showed that the number of subway users decreased after the implementation of strict social distancing, coinciding with a decrease in the number of patients with asthma. These findings suggest that social distancing measures implemented to control COVID-19 may reduce the incidence and exacerbation of asthma.

Self-Thermal Management in Filtered Selenium-Terminated MXene Films for Flexible Safe Batteries.

Li-ion batteries with superior interior thermal management are crucial to prevent thermal runaway and ensure safe, long-lasting operation at high temperatures or during rapid discharging and charging. Typically, such thermal management is achieved by focusing on the separator and electrolyte. Here, the study introduces a Se-terminated MXene free-standing electrode with exceptional electrical conductivity and low infrared emissivity, synergistically combining high-rate capacity with reduced heat radiation for safe, large, and fast Li+ storage. This is achieved through a one-step organic Lewis acid-assisted gas-phase reaction and vacuum filtration. The Se-terminated Nb2Se2C outperformed conventional disordered O/OH/F-terminated materials, enhancing Li+-storage capacity by ≈1.5 times in the fifth cycle (221 mAh·g-1 at 1 A·g-1) and improving mid-infrared adsorption with low thermal radiation. These benefits result from its superior electrical conductivity, excellent structural stability, and high permittivity in the infrared region. Calculations further reveal that increased permittivity and conductivity along the z-direction can reduce heat radiation from electrodes. This work highlights the potential of surface groups-terminated layered material-based free-standing flexible electrodes with self-thermal management ability for safe, fast energy storage.

Soft Bioelectronics Using Nanomaterials and Nanostructures for Neuroengineering.

The identification of neural networks for large areas and the regulation of neuronal activity at the single-neuron scale have garnered considerable attention in neuroscience. In addition, detecting biochemical molecules and electrically, optically, and chemically controlling neural functions are key research issues. However, conventional rigid and bulky bioelectronics face challenges for neural applications, including mechanical mismatch, unsatisfactory signal-to-noise ratio, and poor integration of multifunctional components, thereby degrading the sensing and modulation performance, long-term stability and biocompatibility, and diagnosis and therapy efficacy. Implantable bioelectronics have been developed to be mechanically compatible with the brain environment by adopting advanced geometric designs and utilizing intrinsically stretchable materials, but such advances have not been able to address all of the aforementioned challenges.Recently, the exploration of nanomaterial synthesis and nanoscale fabrication strategies has facilitated the design of unconventional soft bioelectronics with mechanical properties similar to those of neural tissues and submicrometer-scale resolution comparable to typical neuron sizes. The introduction of nanotechnology has provided bioelectronics with improved spatial resolution, selectivity, single neuron targeting, and even multifunctionality. As a result, this state-of-the-art nanotechnology has been integrated with bioelectronics in two main types, i.e., bioelectronics integrated with synthesized nanomaterials and bioelectronics with nanoscale structures. The functional nanomaterials can be synthesized and assembled to compose bioelectronics, allowing easy customization of their functionality to meet specific requirements. The unique nanoscale structures implemented with the bioelectronics could maximize the performance in terms of sensing and stimulation. Such soft nanobioelectronics have demonstrated their applicability for neuronal recording and modulation over a long period at the intracellular level and incorporation of multiple functions, such as electrical, optical, and chemical sensing and stimulation functions.In this Account, we will discuss the technical pathways in soft bioelectronics integrated with nanomaterials and implementing nanostructures for application to neuroengineering. We traced the historical development of bioelectronics from rigid and bulky structures to soft and deformable devices to conform to neuroengineering requirements. Recent approaches that introduced nanotechnology into neural devices enhanced the spatiotemporal resolution and endowed various device functions. These soft nanobioelectronic technologies are discussed in two categories: bioelectronics with synthesized nanomaterials and bioelectronics with nanoscale structures. We describe nanomaterial-integrated soft bioelectronics exhibiting various functionalities and modalities depending on the integrated nanomaterials. Meanwhile, soft bioelectronics with nanoscale structures are explained with their superior resolution and unique administration methods. We also exemplified the neural sensing and stimulation applications of soft nanobioelectronics across various modalities, showcasing their clinical applications in the treatment of neurological diseases, such as brain tumors, epilepsy, and Parkinson's disease. Finally, we discussed the challenges and direction of next-generation technologies.

The Influence of Tacrolimus on Cellular Morphology, Cellular Viability, Osteogenic Differentiation, and mRNA Expression within Stem Cell Spheroids.

Background and Objectives: Tacrolimus is a macrolide lactone compound derived from the bacterium Streptomyces tsukubensis, widely known as an immunosuppressant. In basic research, the effects of tacrolimus on osteogenic differentiation have been tested using mesenchymal stem cells. In this study, tacrolimus's effects on the cellular survival and osteogenic differentiation of stem cell spheroids were investigated. Materials and Methods: Concave microwells were used to form stem cell spheroids in the presence of tacrolimus at final concentrations of 0 µg/mL, 0.1 µg/mL, 1 µg/mL, 10 µg/mL, and 100 µg/mL. A microscope was used to test cellular vitality qualitatively, and an assay kit based on water-soluble tetrazolium salt was used to measure cellular viability quantitatively. Alkaline phosphatase activity and an anthraquinone dye test for measuring calcium deposits were used to assess osteogenic differentiation. To assess the expression of osteogenic differentiation, a quantitative polymerase chain reaction, Western blot, and RNA sequencing were performed. Results: Spheroids across all concentrations maintained a relatively uniform and spherical shape. Cell viability assay indicated that tacrolimus, up to a concentration of 100 µg/mL, did not significantly impair cell viability within spheroids cultured in osteogenic media. The increase in calcium deposition, particularly at lower concentrations of tacrolimus, points toward an enhancement in osteogenic differentiation. There was an increase in COL1A1 expression across all tacrolimus concentrations, as evidenced by the elevated mean and median values, which may indicate enhanced osteogenic activity. Conclusions: This study showed that tacrolimus does not significantly impact the viability of stem cell spheroids in osteogenic media, even at high concentrations. It also suggests that tacrolimus may enhance osteogenic differentiation, as indicated by increased calcium deposition and COL1A1 expression. These findings advance our understanding of tacrolimus's potential roles in tissue repair, regeneration, and stem cell-based therapeutic applications.

The discovery of an anti-inflammatory monoterpenoid, neoroseoside from the Zea mays.

A new monoterpenoid, neoroseoside (1), along with two previously reported compounds, 2″-O-α-l-rhamnosyl-6-C-fucosylluteolin (2) and farobin A (3) were isolated from the Zea mays. The structure of compound 1 was determined through the analysis spectroscopic data, including mass spectrometry (MS), infrared (IR) spectroscopy, and nuclear magnetic resonance (NMR) data. The absolute configurations of 1 were deduced from the comparing the values of optical rotations and from the interpretation of electronic circular dichroism (ECD) spectra. Compounds 2 and 3 displayed moderate antibacterial activity against Streptococcus mutans ATCC 25175 (inhibition rates 24 % and 28 %, respectively) and Streptococcus sobrinus ATCC 33478 (inhibition rate of 26 %), at a concentration of 100 µg/mL, whereas compound 1 did not have any significant antibacterial activities. The compounds 1-3 also showed anti-inflammatory activity on cytokine IL-6 and TNF-α.

Self-Assembly Enabled Printable Asymmetric Self-Insulated Stretchable Conductor for Human Interface.

Soft and stretchable conductors with high electrical conductivity and tissue-like mechanical properties are crucial for both on-skin and implantable electronic devices. Liquid metal-based conductors hold great promise due to their metallic conductivity and minimal stiffness. However, the surface oxidation of liquid metal particles in polymeric matrices poses a challenge in forming a continuous pathway for highly conductive elastic composites. Here, it is reported a printable composite material based on liquid metal and conducting polymer that undergoes a self-assembly process, achieving high conductivity (2089 S cm-1) in the bottom surface while maintaining an insulated top surface, high stretchability (>800%), and a modulus akin to human skin tissue. This material is further applied to fabricate skin-interfaced strain sensors and electromyogram sensors through 3D printing.

Regeneration of Rabbit Calvarial Defects with Combination of Stem Cells and Enamel Matrix Derivative: A Microcomputed Tomography and Histological Evaluation Comparing Two- and Three-Dimensional Cell Constructs.

Background and Objectives: This study addresses the challenge of bone regeneration in calvarial defects, exploring the efficacy of stem cell-based therapies and enamel matrix derivative (EMD) in tissue engineering. It assesses the regenerative potential of two- and three-dimensional cell constructs combined with mesenchymal stem cells (MSCs) and EMD in rabbit calvarial defects. Materials and Methods: This research involved the use of bone-marrow-derived MSCs cultured in silicon elastomer-based concave microwells to form spheroids. White rabbits were grouped for different treatments, with Group 1 as control, Group 2 receiving only EMD, Group 3 getting EMD plus stem cells, and Group 4 being treated with EMD plus stem cell spheroids. Computed tomography (CT) and microcomputed tomography (micro-CT) imaging were used for structural assessment, while histological evaluations were conducted using hematoxylin and eosin, Masson's trichrome, and Picro-sirius red staining. Results: CT and micro-CT analyses revealed varying degrees of bone regeneration among the groups. Group 4, treated with three-dimensional MSC spheroids and EMD, showed the most significant improvement in bone regeneration. Histological analyses corroborated these findings, with Group 4 displaying enhanced bone formation and better collagen fiber organization. Conclusions: The study supported the biocompatibility and potential efficacy of three-dimensional MSC constructs combined with EMD in bone regeneration. Further investigations are needed to confirm these findings and optimize treatment protocols.

Phase-separated stretchable conductive nanocomposite to reduce contact resistance of skin electronics.

Skin electronics, facilitating a high-quality interface between external devices and human skin for recording physiological and/or electrophysiological signals as well as delivering external electrical and/or mechanical energy into the human body, has shown significant progress. However, achieving mechanically conformal contact and electrically low contact resistance at the device-skin interface remains challenging. Here, we propose a material strategy to potentially address such an issue by using phase separation of silver nanowires and silver nanoparticles (Ag NWs and Ag NPs) within a stretchable conductive nanocomposite (NC). This phase-separated NC ensures low contact resistance and high conductivity, which are key requirements in skin electronics, while maintaining excellent mechanical contact with the skin. To achieve phase separation, we hydrophobically treated the surfaces of Ag NWs and Ag NPs. Then, as the NC solidified, the solvent contained in the NC was slowly evaporated to sufficiently precipitate Ag NPs within the NC. As a result, the phase-separated NC exhibited high conductivity (~ 18,535 S cm-1), excellent stretchability (~ 80%), and low contact resistance on both the top and bottom NC surfaces (average ~ 0.132 Ω). The phase-separated NC has enabled implementation of high performance skin-mounted devices, including strain sensors, electrophysiological sensors, and a wearable heater.

Sirt6-Mediated Cell Death Associated with Sirt1 Suppression in Gastric Cancer.

BACKGROUND: Gastric cancer, one of the leading causes of cancer-related death, is strongly associated with H. pylori infection, although other risk factors have been identified. The sirtuin (Sirt) family is involved in the tumorigenesis of gastric cancer, and sirtuins can have pro- or anti-tumorigenic effects. METHODS: After determining the overall survival rate of gastric cancer patients with or without Sirt6 expression, the effect of Sirt6 upregulation was also tested using a xenograft mouse model. The regulation of Sirt6 and Sirt1, leading to the induction of mouse double minute 2 homolog (MDM2) and reactive oxygen species (ROS), was mainly analyzed using Western blotting and immunofluorescence staining, and gastric cancer cell (SNU-638) death associated with these proteins was measured using flow cytometric analysis. RESULTS: Sirt6 overexpression led to Sirt1 suppression in gastric cancer cells, resulting in a higher level of gastric cancer cell death in vitro and a reduced tumor volume. ROS and MDM2 expression levels were upregulated by Sirt6 overexpression and/or Sirt1 suppression according to Western blot analysis. The upregulated ROS ultimately led to gastric cancer cell death as determined via Western blot and flow cytometric analysis. CONCLUSION: We found that the upregulation of Sirt6 suppressed Sirt1, and Sirt6- and Sirt1-induced gastric cancer cell death was mediated by ROS production. These findings highlight the potential of Sirt6 and Sirt1 as therapeutic targets for treating gastric cancer.

Mechanistic Basis of Conductivity in Carbon Dioxide-Expanded Electrolytes: A Joint Experimental-Theoretical Study.

Electrolyte conductivity contributes to the efficiency of devices for electrochemical conversion of carbon dioxide (CO2) into useful chemicals, but the effect of the dissolution of CO2 gas on conductivity has received little attention. Here, we report a joint experimental-theoretical study of the properties of acetonitrile-based CO2-expanded electrolytes (CXEs) that contain high concentrations of CO2 (up to 12 M), achieved by CO2 pressurization. Cyclic voltammetry data and paired simulations show that high concentrations of dissolved CO2 do not impede the kinetics of outer-sphere electron transfer but decrease the solution conductivity at higher pressures. In contrast with conventional behaviors, Jones reactor-based measurements of conductivity show a nonmonotonic dependence on CO2 pressure: a plateau region of constant conductivity up to ca. 4 M CO2 and a region showing reduced conductivity at higher [CO2]. Molecular dynamics simulations reveal that while the intrinsic ionic strength decreases as [CO2] increases, there is a concomitant increase in ionic mobility upon CO2 addition that contributes to stable solution conductivities up to 4 M CO2. Taken together, these results shed light on the mechanisms underpinning electrolyte conductivity in the presence of CO2 and reveal that the dissolution of CO2, although nonpolar by nature, can be leveraged to improve mass transport rates, a result of fundamental and practical significance that could impact the design of next-generation systems for CO2 conversion. Additionally, these results show that conditions in which ample CO2 is available at the electrode surface are achievable without sacrificing the conductivity needed to reach high electrocatalytic currents.

Engagement Measures in Maltreatment Prevention Studies: A Scoping Review.

Prevention services can promote public health by building protective factors and reducing maltreatment risk. Yet, engaging caregivers in prevention services presents a unique set of challenges. Measurement studies are important first steps to increase the knowledge of caregiver engagement in prevention services. The purpose of this scoping review was to investigate how family engagement has been measured and operationalized in the studies of maltreatment prevention/positive parenting programs. The review examined quantitative and mixed methods studies conducted in the U.S., which measured multiple dimensions of client engagement, including behavioral, attitudinal, and relational domains. A total of 88 studies selected from PubMed, CINAHL, ERIC, PsycINFO, Social Work Abstracts, Academic Search Premier, and Web of Science were included in this review. Results indicated that studies examine engagement constructs in all three domains of engagement with a primary focus on behavioral engagement. The attitudinal and relational engagement was mostly assessed through general satisfaction surveys, and a limited number of studies utilized validated measures to assess those constructs. While most studies reported acceptable internal reliabilities, only two studies reported other dimensions of psychometric qualities. Only one validated measure was found, which assessed client perceptions of provider cultural competence. More measurement studies are needed to further incorporate multiple dimensions of engagement into the studies of maltreatment prevention programs, which can inform the effort to develop tailored implementation strategies to fully engage various groups of parents in maltreatment prevention programs.

"Nulichal" Barley Extract Suppresses Nitric Oxide and Pro-Inflammatory Cytokine Production by Lipopolysaccharides in RAW264.7 Macrophage Cell Line.

The cultivar "Nulichal," a type of naked waxy barley (Hordeum vulgare L.), was developed by the National Institute of Crop Science, Rural Development Administration, Korea, in 2010. In this study, we investigated the anti-inflammatory and antioxidant properties of the "Nulichal" ethanol extract (NRE) using various assays. The NRE exhibited a total phenolic content of 7.55±0.30 mg gallic acid equivalent/g and a flavonoid content of 1.74±0.08 mg rutin equivalent/g. Cell viability assays showed no toxicity of NRE on RAW264.7 macrophage cells up to concentrations of 500 µg/mL. The NRE (300 and 500 µg/mL) significantly reduced nitric oxide (NO) production induced by lipopolysaccharides (LPS). It also down-regulated the mRNA expression and protein levels of inducible NO synthase and cyclooxygenase-2 in a dose-dependent manner. Moreover, the NRE treatment significantly decreased the levels of pro-inflammatory cytokines, such as tumor necrosis factor-α and interleukin-6, and their mRNA expression compared to LPS treatment alone. The NRE demonstrated strong free radical scavenging activity against 2,2-diphenyl-1-picrylhydrazyl and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) radicals in a dose-dependent manner. The ferric reducing antioxidant power assay also showed increased antioxidant activity with increasing NRE concentrations. These findings suggest that the NRE can be used as a functional food with anti-inflammatory and antioxidant properties.

Comparison of the Standard E TB-Feron ELISA and QuantiFERON-TB Gold PLUS assays: the advantageous use of whole recombinant protein antigens for latent tuberculosis diagnosis.

The laboratory diagnosis of latent tuberculosis is often performed using interferon-gamma release assays. Here, we compared two enzyme-linked immunosorbent assay-based interferon-gamma release assays, namely, the newly developed Standard E TB-Feron enzyme-linked immunosorbent assay (STFE) and the QuantiFERON-TB Gold PLUS assay (QFT-GP), using samples from 155 participants. The STFE is based on using whole EAST6 and CFP10 recombinant antigens for latent tuberculosis diagnosis. The participants were classified into four groups and screened using both assays per the manufacturers' instructions. Thereafter, two statistical analyses were conducted to compare the obtained results. First, the STFE results were compared with the QTF-GP results (used as the gold standard) to calculate the total concordance, sensitivity, and specificity of STFE. Second, positivity and negativity concordances were calculated to differentiate healthy participants from participants with tuberculosis. The STFE showed 97% and 94% sensitivity and specificity, respectively. Furthermore, its positivity and negativity concordances were 91% and 98%, respectively. These results indicate the coordinated clinical performance of STFE in detecting latent tuberculosis and its improved performance in targeting tuberculosis-infected participants. Based on the comparison of the latent tuberculosis diagnostic abilities of STFE and QFT-GP, we establish the suitability and superior performance of STFE as a diagnostic tool.

Moderating Role of Communication Competence in the Association between Professionalism and Job Satisfaction in Korean Millennial and Generation Z Nurses: A Cross-Sectional Study.

Millennial and Generation Z (MZ generation) nurses, the core of the Republic of Korean nursing workforce, are leaving hospitals. We, therefore, aimed to determine the mediating role of communication competence between nursing professionalism and job satisfaction of MZ generation nurses in Republic of Korea. A total of 188 nurses aged 20-39 years belonging to the MZ generation, who had been working in a general hospital for over six months, participated in an online survey from 27 October 2022 to 11 January 2023. Data analysis was conducted using the bootstrapping method with the SPSS PROCESS macro program to confirm the mediating role of communication competence. Job satisfaction, professionalism, and communication skills were significantly positively correlated (r = 0.36-0.72, p < 0.001). Communication competence was found to be a mediating factor in the relationship between professionalism and job satisfaction. The results showed that when professionalism related to job satisfaction, good communication further enhanced job satisfaction. In order to enhance MZ generation nurses' job satisfaction, it is necessary to improve nursing professionalism and implement training programs to improve communication skills considering generation-specific characteristics.

Impact of COVID-19 Pandemic on the Incidence of Pediatric Acute Otitis Media in Seoul, South Korea.

OBJECTIVE: The implementation of nonpharmaceutical interventions (NPIs) for coronavirus disease 2019 (COVID-19) may affect the incidence of infectious diseases. This study aimed to evaluate the changes in the incidence of pediatric acute otitis media (AOM) after the COVID-19 outbreak in Seoul, South Korea. STUDY DESIGN: Retrospective cohort. SETTING: Tertiary referral center. PATIENTS: We ascertained the daily number of COVID-19 and pediatric AOM patients between January 20, 2020, and June 19, 2020. During the same period, the number of children using public transportation was used as an index for implementing NPIs. The same period 1 year ago was set as the control period. INTERVENTION: Diagnostic. MAIN OUTCOME MEASURE: The differences in the incidence of AOM and implementation of NPIs between the COVID-19 pandemic and control period were analyzed using segmented regression analyses. Negative values of difference meant that the number in the COVID-19 pandemic period declined compared with the control period. RESULTS: The study period was divided into two sections based on the change point of the COVID-19 cases. In the first period, the increased number of COVID-19 cases decreased, and in the second period, the number of COVID-19 cases increased again. Similar trends were observed in the incidence of AOM and NPI implementation. Before the change point, the study found a significant decreasing trend in the differences in pediatric AOM cases and children using public transportation. However, these trends changed after the change point, with a significant increase in both indices. CONCLUSION: Our findings indicate that NPIs for COVID-19 may influence the incidence of pediatric AOM.

Metal-Like Stretchable Nanocomposite Using Locally-Bundled Nanowires for Skin-Mountable Devices.

Stretchable conductive nanocomposites have been intensively studied for wearable bioelectronics. However, development of nanocomposites that simultaneously feature metal-like conductivity(> 100 000 S cm-1 ) and high stretchability (> 100%) for high-performance skin-mountable devices is still extremely challenging. Here a material strategy for such a nanocomposite is presented by using local bundling of silver nanowires stabilized with dual ligands (i.e., 1-propanethiols and 1-decanethiols). When the nanocomposite is solidified via solvent evaporation under a highly humid condition, the nanowires in the organic solution are bundled and stabilized. The resulting locally-bundled nanowires lower contact resistance while maintain their percolation network, leading to high conductivity. Dual ligands of 1-propanethiol and 1-decanethiol further boost up the conductivity. As a result, a nanocomposite with both high conductivity of ≈122,120 S cm-1 and high stretchability of ≈200% is obtained. Such superb electrical and mechanical properties are critical for various applications in skin-like electronics, and herein, a wearable thermo-stimulation device is demonstrated.

Bone Morphogenetic Protein-9 Promotes Osteogenic Differentiation and Mineralization in Human Stem-Cell-Derived Spheroids.

Background and Objectives: Alkaline phosphatase activity, mineralized matrix, and osteogenic-related gene expression have been shown to increase in response to bone morphogenetic protein-9 (BMP-9). In this study, spheroids derived from human gingival stem cells were used to determine the effects of BMP-9 on cell survival, osteogenesis, and mineralization. Materials and Methods: Human gingival stem cells were used to produce spheroids and then grown to concentrations of 0, 0.1, 1, 10, and 100 ng/mL with BMP-9. On days 1, 3, 5, and 7, morphological examination was carried out. A live/dead assay and Cell Counting Kit-8 was used to assess the vitality of cells. On days 7 and 14, alkaline phosphatase activity assays were carried out using a commercially available kit to examine the osteogenic differentiation of cell spheroids. Alizarin Red Staining was performed on the 7th and 14th days to evaluate mineralization, and RUNX2 and COL1A1 expression levels were evaluated on the 7th and 14th days using real-time polymerase chain reactions. Results: The BMP-9 added at the measured quantities did not appear to alter the shape of the well-formed spheroids produced by stem cells on day 1. In addition, treatment with BMP-9 at doses of 0, 0.1, 1, 10, or 100 ng/mL did not significantly alter cell diameter. Throughout the whole experimental process, viability was maintained. On day 14, the alkaline phosphatase activity in the groups dosed with 0.1, 1, 10, or 100 ng/mL was statistically higher than that in the unloaded control group (p < 0.05). According to qPCR data, the mRNA expression level of RUNX2 with 1 ng/mL dosing was higher on day 7 compared to that of the unloaded control group (p < 0.05). Conclusions: These findings suggest that BMP-9 can be employed to stimulate early osteogenic differentiation in stem cell spheroids.

Stretchable Low-Impedance Conductor with Ag-Au-Pt Core-Shell-Shell Nanowires and in Situ Formed Pt Nanoparticles for Wearable and Implantable Device.

Mechanically soft metallic nanocomposites have gained much attention as a key material for intrinsically stretchable biointegrated devices. However, it has been challenging to develop a stretchable conductive nanocomposite with all the desired material characteristics including high conductivity, high stretchability, low cytotoxicity, and low impedance. Here, we present a material strategy for the stretchable conductive nanocomposite, particularly emphasizing low impedance, by combining silver-gold-platinum core-shell-shell nanowires and homogeneously dispersed in situ synthesized platinum nanoparticles (Pt NPs). The highly embossed structure of the outermost Pt shell, together with the intrinsic electrical property of Pt, contributes to minimizing the impedance. The gold-platinum double-layer sheath prevents leaching of cytotoxic Ag ions, thus improving biocompatibility. Homogeneously dispersed Pt NPs, synthesized in situ during fabrication of the nanocomposite, simultaneously enhance conductivity, reduce impedance, and improve stretchability by supporting the percolation network formation. This intrinsically stretchable nanocomposite conductor can be applied to wearable and implantable bioelectronics for recording biosignals and delivering electrical stimulations in vivo.

Effects of Enamel Matrix Derivative on Cell Spheroids Made of Stem Cells Obtained from the Gingiva on Osteogenic Differentiation.

Background and Objectives: A derivative of the enamel matrix was used to speed up periodontal regeneration, including the formation of new cementum, alveolar bone, and periodontal ligament. In this study, human gingiva-derived stem cell-derived cell spheroids were used to assess the effects of an enamel matrix derivative on cell viability, osteogenic differentiation, and mineralization. Materials and Methods: Human gingiva-derived stem cells were used to create spheroids, which were then coupled with unloaded control groups and an enamel matrix derivative at a final concentration of 2.7, 27, 270, and 2700 µg/mL. The morphological examination of the created stem cell spheroids took place on days 1, 3, 5, and 7. The Live/Dead Kit assay was used to determine the qualitative viability of cells on days 3 and 7. Using the Cell Counting Kit-8, the quantitative vitality of the cell spheroids was assessed on days 1, 3, and 5. On days 7 and 14, alkaline phosphatase activity assays and Alizarin Red S staining were carried out to examine the osteogenic differentiation of the cell spheroids. RUNX2 and COL1A1 expression levels on days 7 and 14 were determined using real-time polymerase chain reaction. Results: The added enamel matrix derivative at the tested concentrations did not significantly alter the morphology of the applied stem cells' well-formed spheroids on day 1. On days 3 and 7, the majority of the spheroids' cells fluoresced green while they were being cultivated. Alkaline phosphatase activity data revealed a substantial rise in the 2700 µg/mL group on day 7 when compared to the unloaded control (p < 0.05). On days 7 and 14, calcium deposits were distinctly seen in each group. In the 27 and 2700 µg/mL groups, the treatment with the enamel matrix derivative resulted in noticeably higher values for the Alizarin Red S staining (p < 0.05). qPCR results showed that adding an enamel matrix derivative to the culture of the 27 µg/mL group raised the level of RUNX2 mRNA expression. Conclusions: These results lead us to the conclusion that a derivative of the enamel matrix may be used to promote osteogenic differentiation in stem cell spheroids.

Cold Plasma Treatment Increases Bioactive Metabolites in Oat (Avena sativa L.) Sprouts and Enhances In Vitro Osteogenic Activity of their Extracts.

Cold plasma treatment has been studied to enhance the germination, growth, and bioactive phytochemical production in crops. Here, we aimed to investigate the effects of cold plasma treatment on the growth, bioactive metabolite production, and protein expression related to the physiological and osteogenic activities of oat sprouts. Oat seeds were soaked for 12 h, and then exposed to plasma for 6 min/day for 3 days after sowing. Plasma exposure did not significantly change the growth of oat sprouts; however, increased the content of bioactive metabolites. A single exposure for 6 min on the first day (T-1) increased the content of free amino acids (39.4%), γ-aminobutyric acid (53%), and avenacoside B (23%) compared to the control. Hexacosanol content was the highest in T-3 (6 min exposure on each day for 3 days), 28% higher than that in the control. Oat sprout extracts induced the phosphorylation of adenosine 5'-monophosphate-activated protein kinase and osteoblast differentiation was enhanced by increasing the alkaline phosphatase (ALP) activity; all these effects were induced by plasma treatment. Avenacoside B content was positively correlated with ALP activity (r = 0.911, p < 0.1). These results suggest that plasma treatment has the potential to improve the value of oat sprouts and that it may be used in food fortification to enhance nutritional value for promoting human health.